BACKGROUND Undernutrition is a crucial cause of morbidity and mortality among children in low-or middle-income countries(LMICs).A better understanding of maternal general healthy nutrition knowledge,as well as misbeli...BACKGROUND Undernutrition is a crucial cause of morbidity and mortality among children in low-or middle-income countries(LMICs).A better understanding of maternal general healthy nutrition knowledge,as well as misbeliefs,is highly essential,especially in such settings.In the current era of infodemics,it is very strenuous for mothers to select not only the right source for maternal nutrition information but the correct information as well.AIM To assess maternal healthy nutritional knowledge and nutrition-related misbeliefs and misinformation in an LMIC,and to determine the sources of such information and their assessment methods.METHODS This cross-sectional analytical observational study enrolled 5148 randomly selected Egyptian mothers who had one or more children less than 15 years old.The data were collected through online questionnaire forms:One was for the general nutrition knowledge assessment,and the other was for the nutritional myth score.Sources of information and ways of evaluating internet sources using the Currency,Relevance,Authority,Accuracy,and Purpose test were additionally analyzed.RESULTS The mean general nutrition knowledge score was 29±9,with a percent score of 70.8%±12.1%(total score:41).The median myth score was 9(interquartile range:6,12;total score:18).The primary sources of nutrition knowledge for the enrolled mothers were social media platforms(55%).Half of the mothers managed information for currency and authority,except for considering the author's contact information.More than 60%regularly checked information for accuracy and purpose.The mothers with significant nutrition knowledge checked periodically for the author's contact information(P=0.012).The nutrition myth score was significantly lower among mothers who periodically checked the evidence of the information(P=0.016).Mothers dependent on their healthcare providers as the primary source of their general nutritional knowledge were less likely to hold myths by 13%(P=0.044).However,using social media increased the likelihood of having myths among mothers by approximately 1.2(P=0.001).CONCLUSION Social media platforms were found to be the primary source of maternal nutrition information in the current era of infodemics.However,healthcare providers were the only source for decreasing the incidence of maternal myths among the surveyed mothers.展开更多
Tinnitus is a concerning condition that affects most adults worldwide,with a prevalence of 6.7%.Theories of tinnitus have explained that an increase in spontaneous neural activity at the level of the thalamus could in...Tinnitus is a concerning condition that affects most adults worldwide,with a prevalence of 6.7%.Theories of tinnitus have explained that an increase in spontaneous neural activity at the level of the thalamus could induce tinnitus.There are no standardized objective tests for tinnitus assessment because of its multifaceted nature.Hence,the current study aimed to explore the effect of Tinnitus on Latency and Amplitude of the Auditory Middle Latency Response in Audiological Attendees.The study recruited 50 individuals(25 normals and 25 individuals with tinnitus)who underwent audiological evaluations like Pure tone audiometry,immittance,pitch and loudness matching,THI and middle latency response.The IHS program was used to record MLR,which was obtained using tone burst stimuli of 500 Hz,1 KHz,2 KHz,and 4 KHz at a rate of 7.1/s with a constant duration of 5 ms,for a total of 1500 sweeps.As a covariate,pure tone thresholds were one of the variabilities that were addressed by ANCOVA.The amplitude of the Pa component varied significantly between the tinnitus and control groups,according to the MLR data and no other components of MLR reached that significance.Furthermore,there was no discernible variation in the latency or amplitude of MLR among any of the other components.The latency of the waveforms increased as the stimulus frequency increased.Karl Pearson correlation coefficient showed no significant correlation between THI scores and any of the outcome measures except for Pa amplitude.As the Pa component of MLR showed maximum changes between controls and individuals with tinnitus,the Pa component could be considered a potential tool for identifying neurophysiological changes related to tinnitus.展开更多
Objectives:Flourishing,a central concept in positive psychology,encompasses multifaceted dimensions such as meaning,positive relationships,and engagement.Despite growing research interest,empirical studies focusing sp...Objectives:Flourishing,a central concept in positive psychology,encompasses multifaceted dimensions such as meaning,positive relationships,and engagement.Despite growing research interest,empirical studies focusing specifically on the flourishing of middle school students remain scarce.Given the critical need to promote flourishing among Chinese middle school students,the study aimed to adapt Diener’s Flourishing Scale for Chinese middle school students,examine its psychometric properties,and establish its measurement invariance across gender and time within this population.Methods:Participants were recruited from secondary schools in two Chinese provinces.The Chinese versions of the Flourishing Scale(CFS),along with the Index of Well-being(IWB)and the Satisfaction with Life Scale(SWLS),were employed.Data collection occurred in three phases,the first two for exploratory factor analysis(EFA)and confirmatory factor analysis(CFA),respectively,and the last one for testing longitudinal measurement invariance and gender measurement invariance.Results:The CFS demonstrated excellent discrimination and consistency with Diener’s original model.Significant positive correlations emerged between the CFS scores and well-being(r=0.75,p<0.01)as well as life satisfaction(r=0.74,p<0.01).Cronbach’sαwas 0.948,and the Pearson correlation coefficient(PCC)for test-retest reliability was 0.85(p<0.01).The CFS demonstrated strict measurement invariance across both gender and time.Conclusion:The CFS demonstrates robust psychometric properties—including structural validity,reliability,and measurement invariance—for its application among Chinese middle school students.展开更多
This paper discusses the characteristics and formation mechanism of thin dolomite reservoirs in the lower submember of the second member of the Permian Maokou Formation(lower Mao 2 Member)in the Wusheng-Tongnan area o...This paper discusses the characteristics and formation mechanism of thin dolomite reservoirs in the lower submember of the second member of the Permian Maokou Formation(lower Mao 2 Member)in the Wusheng-Tongnan area of the Sichuan Basin,SW China,through comprehensive analysis of geological,geophysical and geochemical data.The reservoir rocks of the lower Mao 2 Member are dominated by porphyritic vuggy dolomite and calcareous dolomite or dolomitic limestone,which have typical karst characteristics of early diagenetic stage.The dolomites at the edge of the karst system and in the fillings have dissolved estuaries,and the dolomite breccia has micrite envelope and rim cement at the edge,indicating that dolomitization is earlier than the early diagenetic karstification.The shoal facies laminated dolomite is primarily formed by the seepage reflux dolomitization of moderate-salinity seawater.The key factors of reservoir formation are the bioclastic shoal deposition superimposed with seepgae reflux dolomitization and the karstification of early diagenetic stage,which are locally reformed by fractures and hydrothermal processes.The development of dolomite vuggy reservoir is closely related to the upward-shallowing sequence,and mainly occurs in the late highstand of the fourth-order cycle.Moreover,the size of dolomite is closely related to formation thickness,and it is concentrated in the formation thickness conversion area,followed by the thinner area.According to the understanding of insufficient accommodation space in the geomorphic highland and the migration of granular shoal to geomorphic lowland in the late highstand of the third-order cycle,it is proposed that the large-scale shoal-controlled dolomite reservoirs are distributed along structural highs and slopes,and the reservoir-forming model with shoal,dolomitization and karstification jointly controlled by the microgeomorphy and sea-level fluctuation in the sedimentary period is established.On this basis,the paleogeomorphology in the lower Mao 2 Member is restored using well-seismic data,and the reservoir distribution is predicted.The prediction results have been verified by the latest results of exploration wells and tests,which provide an important reference for the prediction of thin dolomite reservoirs under similar geological setting.展开更多
BACKGROUND Solid fuel use for cooking and heating is a major environmental risk factor,yet its association with new-onset heart disease(HD)remains unclear.The aim of this study was to investigate the relationship betw...BACKGROUND Solid fuel use for cooking and heating is a major environmental risk factor,yet its association with new-onset heart disease(HD)remains unclear.The aim of this study was to investigate the relationship between solid fuel exposure and new-onset HD in a large cohort.METHODS Multivariable logistic regression models assessed associations between cooking/heating fuel types(coal,crop residue/wood,liquefied petroleum gas,natural gas,and others)and new-onset HD.Subgroup analyses explored effect modification by age,sex,education,smoking,alcohol use,and region.RESULTS A prospective cohort study included 5915 participants,with 781 participants(13.2%)developing new-onset HD.Coal use for cooking showed an initial association with new-onset HD risk(OR=1.41,95%CI:1.06–1.86,P=0.02),which attenuated after full adjustment(OR=1.28,95%CI:0.96–1.72,P=0.10).Coal use for heating demonstrated robust associations across all models(OR=1.86,95%CI:1.42–2.43,P<0.001).Crop residue/wood burning for heating was also significant(Model 2:OR=1.40,95%CI:1.06–1.86,P=0.02).Subgroup analyses revealed stronger associations among females,non-smokers,non-drinkers,and less-educated participants.Geographic stratification showed significant associations in southern but not northern regions.CONCLUSIONS Solid fuel use,particularly coal for heating,is associated with increased new-onset HD risk.Reducing solid fuel exposure is crucial for HD prevention in low-resource settings.展开更多
Background: Chronic low back pain is a leading cause of morbidity and disability globally. Low and Middle-Income Countries (LMICs) tend to be more affected, with chronic low back pain (CLBP) being among the leading pr...Background: Chronic low back pain is a leading cause of morbidity and disability globally. Low and Middle-Income Countries (LMICs) tend to be more affected, with chronic low back pain (CLBP) being among the leading presenting complaints at specialist consultation. The exact burden of this disease is sparingly known in our setting. Objective: To evaluate the burden of chronic low back pain at the Yaounde Central Hospital. Methods: This was a descriptive cross-sectional study for a period of 3 months, from March 2022 to May 2022. After obtaining ethical clearance and research authorisations, data was collected using structured questionnaires from patients with chronic low back pain presenting at the Yaounde Central Hospital during the aforementioned time frame. This data was then tabulated with the Statistical Package for Social Sciences (SPSS 23.0), and disability was assessed using the modified Roland Morris Disability Questionnaire and the Oswestry Disability Index. Data analysis was done using the International Business Machines Statistical Package for Social Sciences (IBM-SPSS) VERSION 23.0. Results: 115 cases of CLBP were included. The mean age was 52.62 years, and the sex ratio was 0.3. The average monthly income was less than 50,000 frs CFA, in 37.4% of cases. In 57.9%, patients had a job that involved physical labour. The patients had a secondary level of education in 40.9%, and alcohol consumption was observed in 36%. The average number of days of a work stoppage due to LBP was 12.75 days (±12SD), and the median duration of CLBP was 7.15 (7.5SD) years. The median pain intensity was 7 (±2SD), with leg pain and sensory neuropathy observed in 67.8% and 63.5% respectively. Lumbar X-ray was done in 45.2% and revealed lumbar osteoarthrosis in 62.4%. Hypertension as a comorbidity was observed in 26.1%. Medical treatment was used at least once in 98.3% of cases. The average cost of management per month was assessed, and the median was 52,000 FCFA (±20,876 SD). Using the Oswestry Disability Questionnaire, 46 patients, that is 40% of the study population, were classified as severely disabled with a median ODI score of 40%. The factors which were independently associated with disability were level of education, alcohol consumption, treatment modality, pain intensity, body mass index (BMI), psychological wellbeing and number of sick leave days. Conclusion: Chronic low back pain is common in our setting. There is a female predominance with the mean age of the study population situated in the 5th decade. Low-income earners and patients with a job involving physical labour were the most affected. Medical treatment was the main therapeutic modality, with the average cost of management per month being above the average monthly income of the greater majority of the patients. Several factors influenced disability, some of which were independently associated with it, such as level of education, alcohol consumption and treatment modality.展开更多
Drought is an important disaster factor disturbing the stability of the ecosystem in the middle reaches of the Yellow River(YRM).In this study,the spatiotemporal distribution of drought in the YRM from 2000 to 2021 wa...Drought is an important disaster factor disturbing the stability of the ecosystem in the middle reaches of the Yellow River(YRM).In this study,the spatiotemporal distribution of drought in the YRM from 2000 to 2021 was quantitatively investigated by constructing the TVPDI(Temperature-VegetationPrecipitation Dryness Index),and its driving mechanism was explored.The results show that:(1)a significant decreasing trend was observed in the regional annual TVPDI of the YRM,while the autumn TVPDI index showed an increasing trend during 2000-2021.(2)Plants are more susceptible to drought during the growing season.(3)Drought in YRM showed significant spatial heterogeneity,and the high gully area in the Loess Plateau and the earth-rocky mountain areas were less affected by drought than other regions.(4)The Structural Equation Model(SEM)indicated that regional soil moisture and vegetation coverage have a direct influence on regional TVPDI variation.This study has explored the regional differences of drought in different seasons and landforms in the YRM,providing a basis for carrying out targeted seasonal ecological management and refining regional environmental governance,as well as a reference for formulating differentiated ecological restoration and water resource allocation strategies according to local conditions.展开更多
This paper selects sampling sections for the mainstream and tributaries of the middle and lower reaches of the Yellow River,collects river water and sediment samples during the flood season for pollen analysis,and use...This paper selects sampling sections for the mainstream and tributaries of the middle and lower reaches of the Yellow River,collects river water and sediment samples during the flood season for pollen analysis,and uses methods such as Geodetector to explore the distribution characteristics and influencing factors of pollen.The results show significant variations in vegetation composition across different watersheds,leading to notable differences in both the percentage and concentration of pollen types.Pollen concentration in river water is generally higher in the mainstream compared to tributaries,while sediment pollen percentage and concentration are typically lower in the mainstream than in tributaries.The concentration of suspended solids is the most significant factor affecting pollen concentration in the Yellow River,with this effect being particularly prominent outside the Shanxi-Shaanxi Gorge.Abundant coarse sand and rapid flow velocities are likely responsible for the high suspended solids concentration and lower pollen concentration observed in the mainstream of the Shanxi-Shaanxi Gorge.In sediments,clay content is the primary factor influencing pollen concentration,and its interaction with silt and flow velocity has a more prominent influence on pollen concentration.At the Yellow River section below the Shanxi-Shaanxi Gorge,sediment pollen and clay concentrations significantly increase.The changes in pollen concentration in the river water before and after the reservoir are consistent with the suspended solids concentration,while the changes in sediment pollen concentration are consistent with the clay content.Notably,pollen concentrations in sediments decrease more significantly after passing through a reservoir compared to changes observed in river water samples.Overall,there is a strong correlation between river pollen and topsoil pollen,which can provide a reliable reflection of the broader vegetation landscape of the watershed.The findings can provide support for paleoenvironmental reconstruction using pollen from alluvial sediments or lakes with river inflows.展开更多
We report the development of a triplex nucleic acid lateral flow immunoassay(NALFIA)for the detection of the genomes of Nipah virus(NiV),Middle East respiratory syndrome coronavirus(MERS-CoV)and Reston ebolavirus(REBO...We report the development of a triplex nucleic acid lateral flow immunoassay(NALFIA)for the detection of the genomes of Nipah virus(NiV),Middle East respiratory syndrome coronavirus(MERS-CoV)and Reston ebolavirus(REBOV),which are intended for screening bats as well as other hosts and reservoirs of these three viruses.Our triplex NALFIA is a two-step assay format:the target nucleic acid in the sample is first amplified using tagged primers,and the tagged dsDNA amplicons are captured by antibodies immobilized on the NALFIA device,resulting in signal development from the binding of a streptavidin-colloidal gold conjugate to a biotin tag on the captured amplicons.Triplex amplification of the N gene of NiV,the UpE gene of MERS-CoV,and the Vp40 gene of REBOV was optimized,and three compatible combinations of hapten labels and antibodies were identified for end point detection.The lowest RNA copy numbers detected by the triplex NALFIA were 8.21e4 for the NiV N target,7.09e1 for the MERS-CoV UpE target,and 1.83e4 for the REBOV Vp40 target.Using simulated samples,the sensitivity and specificity for MERS-CoV and REBOV targets were estimated to be 100%,while the sensitivity and specificity for the NiV target were 91%and 93.3%,respectively.The compliance rate between triplex NALFIA and real-time RT‒PCR was 92%for the NiV N target and 100%for the MERS-CoV UpE and REBOV Vp40 targets.展开更多
Changes in river cross-section morphology have decisive influences on the flood discharge and sand transport capacity of rivers;thus,these changes strongly reflect the vitality of a river.In this paper,based on the ri...Changes in river cross-section morphology have decisive influences on the flood discharge and sand transport capacity of rivers;thus,these changes strongly reflect the vitality of a river.In this paper,based on the river cross-section and water and sediment data of two different periods(1974−1987 and 2007−2021),the trend analysis,change-point analysis and sediment rating curve method were used to analyze the change process of river cross-section morphology and its response to streamflow and sediment changes in the main river stream of the Yellow River at the Longmen hydrological station.From 1974 to 1987(except in 1977),the riverbed experi-enced siltation,and the riverbed elevation rose.Conversely,from 2007 to 2021,the riverbed experienced scouring,and the riverbed el-evation gradually decreased.The cross-section shape changed from rectangular to U-shaped(deeper on the right side)at the Longmen cross-section.The changes in streamflow and sediment processes significantly impacted the evolution of river cross-section.Stream-flow(P<0.05),sediment discharge(P<0.01),and the sediment load coefficients(P<0.01)decreased significantly.The relationship between the water depth and sediment load coefficients followed a power function.The decreasing trend in sediment discharge was sig-nificantly stronger than that in streamflow.Suspended sediment particles tended to become finer.The sediment rating curve indicates that the sediment supply from upstream decreased while the erosive power in the river channel increased,leading to a gradual decline in riverbed elevation at the Longmen cross-section from 2007 to 2021.These findings help us better understand the impacts of ecological restoration on changes in river streamflow and sediment during river evolution.展开更多
Studying the causes of summer(June–July–August)precipitation anomalies in the middle and lower reaches of the Yangtze River(MLYR)and accurately predicting rainy season precipitation are important to society and the ...Studying the causes of summer(June–July–August)precipitation anomalies in the middle and lower reaches of the Yangtze River(MLYR)and accurately predicting rainy season precipitation are important to society and the economy.In recent years,the sea surface temperature(SST)trend factor has been used to construct regression models for summer precipitation.In this study,through correlation analysis,winter SST anomaly predictors and the winter Central Pacific SST trend predictor(CPT)are identified as closely related to the following MLYR summer precipitation(YRSP).CPT can influence YRSP by inducing anomalous circulations over the North Pacific,guiding warm and moist air northward,and inhibiting the development of the anomalous anticyclone over the Northwest Pacific.This has improved the predictive skill of the seasonal regression model for YRSP.After incorporating the CPT,the correlation coefficient of the YRSP regression model improved by 40%,increasing from 0.45 to 0.63,and the root mean squared error decreased by 22%,from 1.15 to 0.90.展开更多
By means of MICAPS data from China Meteorological Administration,the weather dynamics causing precipitation enhancement in the middle and lower Yangtze Valley on January 19,2008 was analyzed.The results showed that th...By means of MICAPS data from China Meteorological Administration,the weather dynamics causing precipitation enhancement in the middle and lower Yangtze Valley on January 19,2008 was analyzed.The results showed that the convergence of cold and warm air was the basic condition of precipitation enhancement,and the influence systems of precipitation enhancement were surface inverse trough,850-700 hPa warm shear and 850-500 hPa low trough,while southwest and southeast low jet were the important dynamic mechanisms of precipitation enhancement,and southwest low jet offered abundant water vapor for precipitation enhancement.展开更多
Since 1985, samples with a total weight of more than 14,000 kg, mainly from three key sections in western and northwestern Hunan, South China, have been processed for conodonts. In strata older than the late Late Camb...Since 1985, samples with a total weight of more than 14,000 kg, mainly from three key sections in western and northwestern Hunan, South China, have been processed for conodonts. In strata older than the late Late Cambrian paraconodonts have proved useful for stratigraphic subdivision and correlation. Thirteen conodont zones are proposed in the Middle Cambrian through lowermost Ordovician. The correlation between these zones and those of North China, western U. S.A., western Newfoundland, Canada, and Iran is discussed. In ascending order, these 13 zones are as follows: The Gapparodus bisulcatus-Westergaardodina brevidens Zone, Shandongodus priscus-Hunanognathus tricuspidatus Zone, Westergaardodina quadrata Zone, Westergaardodina matsushitai-W. grandidens Zone, Westergaardodina lui-W. am Zone, Westergaardodina cf. calix-Prooneotodus rotundatus Zone, Proconodontus tenuiserratus Zone, Proconodontus Zone, Eoconodontus Zone, Cordylodus proavus Zone, Cordylodus intermedius Zone, Cordylodus lindstromi Zone, and Cordylodus angulatus Zone (lower part). The Westergaardodina lui-W. ani and Westergaardodina cf. calix-Prooneotodus rotundatus Zones replace the Westergaardodina proligula and Westergaardodina cf. behrae-Prooneotodus rotundatus Zones, respectively, in the lowermost Upper Cambrian. Two new species (Westergaardodina Iui and Westergaardodina ani) and one conditionally identified species (Westergaardodina cf. calix) are described.展开更多
AIM: To study the feasibility and safety of middle segmental pancreatectomy (MSP) compared with pancreaticoduodenectomy (PD) and extended distal pancreatectomy (EDP). METHODS: We studied retrospectively 36 cases that ...AIM: To study the feasibility and safety of middle segmental pancreatectomy (MSP) compared with pancreaticoduodenectomy (PD) and extended distal pancreatectomy (EDP). METHODS: We studied retrospectively 36 cases that underwent MSP, 44 patients who underwent PD, and 26 who underwent EDP with benign or low-grade malignant lesions in the mid-portion of the pancreas, between April 2003 and December 2009 in Ruijin Hospital. The perioperative outcomes and long-term outcomes of MSP were compared with those of EDP and PD. Periop-erative outcomes included operative time, intraoperative hemorrhage, transfusion, pancreatic fistula, intraabdominal abscess/infection, postoperative bleeding, reoperation, mortality, and postoperative hospital time. Long-term outcomes, including tumor recurrence, newonset diabetes mellitus (DM), and pancreatic exocrine insufficiency, were evaluated. RESULTS: Intraoperative hemorrhage was 316.1 ± 309.6, 852.2 ± 877.8 and 526.9 ± 414.5 mL for the MSP, PD and EDP groups, respectively (P < 0.05). The mean postoperative daily fasting blood glucose level was significantly lower in the MSP group than in the EDP group (6.3 ± 1.5 mmol/L vs 7.3 ± 1.5 mmol/L, P < 0.05). The rate of pancreatic fistula was higher in the MSP group than in the PD group (42% vs 20.5%, P = 0.039), all of the fistulas after MSP corresponded to grade A (9/15) or B (6/15) and were sealed following conservative treatment. There was no significant difference in the mean postoperative hospital stay between the MSP group and the other two groups. After a mean follow-up of 44 mo, no tumor recurrences were found, only one patient (2.8%) in the MSP group vs five (21.7%) in the EDP group developed new-onset insulin-dependent DM postoperatively (P = 0.029). Moreover, significantly fewer patients in the MSP group than in the PD (0% vs 33.3%, P < 0.001) and EDP (0% vs 21.7%, P = 0.007) required enzyme substitution. CONCLUSION: MSP is a safe and organ-preserving option for benign or low-grade malignant lesions in the neck and proximal body of the pancreas.展开更多
Based on the long-term precipitation series with annual time resolution in the middle and lower reaches of the Yellow River and its four sub-regions during 1736-2000 reconstructed from the rainfall and snowfall archiv...Based on the long-term precipitation series with annual time resolution in the middle and lower reaches of the Yellow River and its four sub-regions during 1736-2000 reconstructed from the rainfall and snowfall archives of the Qing Dynasty, the precipitation cycles are analyzed by wavelet analysis and the possible climate forcings, which drive the precipitation changes, are explored. The results show that： the precipitation in the middle and lower reaches of the Yellow River has inter-annual and inter-decadal oscillations like 2-4a, quasi-22a and 70-80a. The 2-4a cycle is linked with El Nino events, and the precipitation is lower than normal year in the occurrence of the El Nino year or the next year; for the quasi-22a and the 70-80a cycles, Wolf Sun Spot Numbers and Pacific Decadal Oscillation （PDO） coincide with the two cycle signals. However, on a 70-80a time scale, the coincidence between solar activity and precipitation is identified before 1830, and strong （weak） solar activity is generally correlated to the dry （wet） periods; after 1830, the solar activity changes to 80-100a quasi-century long oscillation, and the adjusting action to the precipitation is becoming weaker and weaker; the coincidence between PDO and precipitation is shown in the whole time series. Moreover, in recent 100 years, PDO is becoming a pace-maker of the precipitation on the 70-80a time scale.展开更多
Alluvial channel has always adjusted itself to the equilibrium state of sediment transport after it was artificially or naturally disturbed. How to maintain the equilibrium state of sediment transport and keep the riv...Alluvial channel has always adjusted itself to the equilibrium state of sediment transport after it was artificially or naturally disturbed. How to maintain the equilibrium state of sediment transport and keep the river regime stable has always been the concerns of fluvial geomorphologists. The channel in the middle and lower reaches of the Yangtze River is characterized by the staggered distribution of the bifurcated river and the single-thread river. The change of river regime is more violently in the bifurcated river than in the single-thread river. Whether the adjustment of the river regime in the bifurcated river can pass through the single-thread river and propagate to the downstream reaches affects the stabilities of the overall river regime. Studies show that the barrier river reach can block the upstream channel adjustment from propagating to the downstream reaches; therefore, it plays a key role in stabilizing the river regime. This study investigates 34 single-thread river reaches in the mid- dle and lower reaches of the Yangtze River. On the basis of the systematic summarization of the fluvial process of the middle and lower reaches of the Yangtze River, the control factors of barrier river reach are summarized and extracted： the planar morphology of single-thread and meandering; with no flow deflecting node distributed in the upper or middle part of the river reach; the hydraulic geometric coefficient is less than 4; the longitudinal gradient is greater than 12‰, the clay content of the concave bank is greater than 9.5%, and the median diameter of the bed sediment is greater than 0.158 mm. From the Navier-Stokes equation ,the calculation formula of the bending radius of flow dynamic axis is deduced and then the roles of these control factors on restricting the migration of the flow dynamic axis and the formation of the barrier river reach are analyzed. The barrier river reach is considered Such. When the ratio of the migration force of the flow dynamic boundary is less than 1 under different flow levels axis to the constraint force of the channel boundary is less than 1 under different flow levels.The mechanism of the barrier river reach is such that even when the upstream river regime adjusts, the channel boundary of this reach can always constrain the migration amplitude of the flow dynamic axis and centralize the planar position of the main stream line under different upstream river regime conditions, pro- viding a relatively stable incoming flow conditions for the downstream reaches, thereby blocking the upstream river regime adjustment from propagating to the downstream reaches.展开更多
Recent advances in studies of the middle and upper atmosphere and their coupling with the lower atmosphere in China are briefly reviewed. This review emphasizes four aspects: (1) Development of instrumentation for mid...Recent advances in studies of the middle and upper atmosphere and their coupling with the lower atmosphere in China are briefly reviewed. This review emphasizes four aspects: (1) Development of instrumentation for middle and upper atmosphere observation; (2) Analyses and observation of middle and upper atmosphere; (3) Theoretical and modeling studies of planetary wave and gravity wave activities in the middle atmosphere and their relation to lower atmospheric processes; (4) Study on the coupling between the stratosphere and the troposphere.展开更多
The clinical characteristics of patients who presented in poor clinical grade due to ruptured middle cerebral artery aneurysms （MCAAs） associated with large sylvian hematomas （SylH） were ana- lyzed and an ingeniou...The clinical characteristics of patients who presented in poor clinical grade due to ruptured middle cerebral artery aneurysms （MCAAs） associated with large sylvian hematomas （SylH） were ana- lyzed and an ingenious designed prophylactic hinged craniectomy was introduced. Twenty-eight pa- tients were graded into Hunt-Hess grades IV-V and emergency standard micro-neurosurgeries （aneu- rysm clipping, hematoma evacuation and prophylactic hinged craniectomy） were performed, and their clinical data were retrospectively analyzed. 46.43% of the patients reached encouraged favorable out- comes on discharge. The favorable outcome group and the poor outcome group significantly differed in terms of patients＇ anisocoria, Hunt-Hess grade before surgery, extent of the midline shift and time to the surgery after bleeding （P〈0.05）. There were no significant differences in age, sex, volume and location of the hematoma, size of aneurysm between the favorable and poor groups （P〉0.05）. However, ingen- ious designed prophylactic hinged craniectomy efficiently reduced the patients＇ intracranial pressure （ICP） after surgery. It was suggested that preoperative conditions such as Hunt-Hess grading, extent of the midline shift and the occurrence of cerebral hernia affect the prognosis of patients, but time to the surgery after bleeding and prophylactic hinged craniectomy are of significant importance for optimizing the prognosis ofMCAA oatients 19resenting with large SylH.展开更多
Late Mesozoic volcanic-subvolcanic rocks and related iron deposits, known as porphyry iron deposits in China, are widespread in the Ningwu ore district （Cretaceous basin） of the middle-lower Yangtze River polymetall...Late Mesozoic volcanic-subvolcanic rocks and related iron deposits, known as porphyry iron deposits in China, are widespread in the Ningwu ore district （Cretaceous basin） of the middle-lower Yangtze River polymetallic ore belt, East China. Two types of Late Mesozoic magmatic rocks are exposed： one is dioritic rocks closely related to iron mineralization as the hosted rock, and the other one is granodioritic （-granitic） rocks that cut the ore bodies. To understand the age of the iron mineralization and the ore-forming event, detailed zircon U-Pb dating and Hf isotope measurement were performed on granodioritic stocks in the Washan, Gaocun-Nanshan, Dongshan and Heshangqiao iron deposits in the basin. Four emplacement and crystallization （typically for zircons） ages of granodioritic rocks were measured as 126.1±0.5 Ma, 126.8±0.5 Ma, 127.3±0.5 Ma and 126.3±0.4 Ma, respectively in these four deposits, with the LA-MC-ICP-MS zircon U-Pb method. Based on the above results combined with previous dating, it is inferred that the iron deposits in the Ningwu Cretaceous basin occurred in a very short period of 131-127 Ma. In situ zircon Hf compositions of εHf（t） of the granodiorite are mainly from -3 to -8 and their corresponding 176Hf/177Hf ratio are from 0.28245 to 0.28265, indicating similar characteristics of dioritic rocks in the basin. We infer that granodioritic rocks occurring in the Ningwu ore district have an original relationship with dioritic rocks. These new results provide significant evidence for further study of this ore district so as to understand the ore-forming event in the study area.展开更多
Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.Ho...Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.However,the molecular mechanism underlying its efficacy remains unclear.In this study,a middle cerebral artery occlusion(MCAO)rat model was produced by the suture method.Rats received modified constraint-induced movement therapy 1 hour a day for 14 consecutive days,starting from the 7^th day after middle cerebral artery occlusion.Day 1 of treatment lasted for 10 minutes at 2r/min,day 2 for 20 minutes at 2 r/min,and from day 3 onward for 20 minutes at 4 r/min.CatWalk gait analysis,adhesive removal test,and Y-maze test were used to investigate motor function,sensory function as well as cognitive function in rodent animals from the 1st day before MCAO to the 21^st day after MCAO.On the 21^st day after MCAO,the neurotransmitter receptor-related genes from both contralateral and ipsilateral hippocampi were tested by micro-array and then verified by western blot assay.The glutamate related receptor was shown by transmission electron microscopy and the glutamate content was determined by high-performance liquid chromatography.The results of behavior tests showed that modified constraint-induced movement therapy promoted motor and sensory functional recovery in the middle cerebral artery-occluded rats,but had no effect on cognitive function.The modified constraint-induced movement therapy upregulated the expression of glutamate ionotropic receptor AMPA type subunit 3(Gria3)in the hippocampus and downregulated the expression of the beta3-adrenergic receptor gene Adrb3 and arginine vasopressin receptor 1 A,Avprla in the middle cerebral artery-occluded rats.In the ipsilateral hippocampus,only Adra2 a was downregulated,and there was no significant change in Gria3.Transmission electron microscopy revealed a denser distribution the more distribution of postsynaptic glutamate receptor 2/3,which is an a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor,within 240 nm of the postsynaptic density in the contralateral cornu ammonis 3 region.The size and distribution of the synaptic vesicles within 100 nm of the presynaptic active zone were unchanged.Western blot analysis showed that modified constraint-induced movement therapy also increased the expression of glutamate receptor 2/3 and brain-derived neurotrophic factor in the hippocampus of rats with middle cerebral artery occlusion,but had no effect on Synapsin I levels.Besides,we also found modified constraint-induced movement therapy effectively reduced glutamate content in the contralateral hippocampus.This study demonstrated that modified constraint-induced movement therapy is an effective rehabilitation therapy in middle cerebral artery-occluded rats,and suggests that these positive effects occur via the upregulation of the postsynaptic membrane a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor expression.This study was approved by the Institutional Animal Care and Use Committee of Fudan University,China(approval No.201802173 S)on March 3,2018.展开更多
文摘BACKGROUND Undernutrition is a crucial cause of morbidity and mortality among children in low-or middle-income countries(LMICs).A better understanding of maternal general healthy nutrition knowledge,as well as misbeliefs,is highly essential,especially in such settings.In the current era of infodemics,it is very strenuous for mothers to select not only the right source for maternal nutrition information but the correct information as well.AIM To assess maternal healthy nutritional knowledge and nutrition-related misbeliefs and misinformation in an LMIC,and to determine the sources of such information and their assessment methods.METHODS This cross-sectional analytical observational study enrolled 5148 randomly selected Egyptian mothers who had one or more children less than 15 years old.The data were collected through online questionnaire forms:One was for the general nutrition knowledge assessment,and the other was for the nutritional myth score.Sources of information and ways of evaluating internet sources using the Currency,Relevance,Authority,Accuracy,and Purpose test were additionally analyzed.RESULTS The mean general nutrition knowledge score was 29±9,with a percent score of 70.8%±12.1%(total score:41).The median myth score was 9(interquartile range:6,12;total score:18).The primary sources of nutrition knowledge for the enrolled mothers were social media platforms(55%).Half of the mothers managed information for currency and authority,except for considering the author's contact information.More than 60%regularly checked information for accuracy and purpose.The mothers with significant nutrition knowledge checked periodically for the author's contact information(P=0.012).The nutrition myth score was significantly lower among mothers who periodically checked the evidence of the information(P=0.016).Mothers dependent on their healthcare providers as the primary source of their general nutritional knowledge were less likely to hold myths by 13%(P=0.044).However,using social media increased the likelihood of having myths among mothers by approximately 1.2(P=0.001).CONCLUSION Social media platforms were found to be the primary source of maternal nutrition information in the current era of infodemics.However,healthcare providers were the only source for decreasing the incidence of maternal myths among the surveyed mothers.
文摘Tinnitus is a concerning condition that affects most adults worldwide,with a prevalence of 6.7%.Theories of tinnitus have explained that an increase in spontaneous neural activity at the level of the thalamus could induce tinnitus.There are no standardized objective tests for tinnitus assessment because of its multifaceted nature.Hence,the current study aimed to explore the effect of Tinnitus on Latency and Amplitude of the Auditory Middle Latency Response in Audiological Attendees.The study recruited 50 individuals(25 normals and 25 individuals with tinnitus)who underwent audiological evaluations like Pure tone audiometry,immittance,pitch and loudness matching,THI and middle latency response.The IHS program was used to record MLR,which was obtained using tone burst stimuli of 500 Hz,1 KHz,2 KHz,and 4 KHz at a rate of 7.1/s with a constant duration of 5 ms,for a total of 1500 sweeps.As a covariate,pure tone thresholds were one of the variabilities that were addressed by ANCOVA.The amplitude of the Pa component varied significantly between the tinnitus and control groups,according to the MLR data and no other components of MLR reached that significance.Furthermore,there was no discernible variation in the latency or amplitude of MLR among any of the other components.The latency of the waveforms increased as the stimulus frequency increased.Karl Pearson correlation coefficient showed no significant correlation between THI scores and any of the outcome measures except for Pa amplitude.As the Pa component of MLR showed maximum changes between controls and individuals with tinnitus,the Pa component could be considered a potential tool for identifying neurophysiological changes related to tinnitus.
基金supported by Innovation Team Project of General Colleges and Universities in Guangdong Province(Grand number:2022WCXTD004)Guangzhou University of Chinese Medicine Young Innovative and Top-notch Talent(Team)Cultivation Project,Guangzhou Philosophy and Social Sciences Development“14th Five-Year Plan”2024 Annual Project(Co-construction Project)(Grant number:2024GZGJ277)Guangdong Province 2024 Annual Education Science Planning Project(Higher Education Special Project)(Grant number:2024GXJK123).
文摘Objectives:Flourishing,a central concept in positive psychology,encompasses multifaceted dimensions such as meaning,positive relationships,and engagement.Despite growing research interest,empirical studies focusing specifically on the flourishing of middle school students remain scarce.Given the critical need to promote flourishing among Chinese middle school students,the study aimed to adapt Diener’s Flourishing Scale for Chinese middle school students,examine its psychometric properties,and establish its measurement invariance across gender and time within this population.Methods:Participants were recruited from secondary schools in two Chinese provinces.The Chinese versions of the Flourishing Scale(CFS),along with the Index of Well-being(IWB)and the Satisfaction with Life Scale(SWLS),were employed.Data collection occurred in three phases,the first two for exploratory factor analysis(EFA)and confirmatory factor analysis(CFA),respectively,and the last one for testing longitudinal measurement invariance and gender measurement invariance.Results:The CFS demonstrated excellent discrimination and consistency with Diener’s original model.Significant positive correlations emerged between the CFS scores and well-being(r=0.75,p<0.01)as well as life satisfaction(r=0.74,p<0.01).Cronbach’sαwas 0.948,and the Pearson correlation coefficient(PCC)for test-retest reliability was 0.85(p<0.01).The CFS demonstrated strict measurement invariance across both gender and time.Conclusion:The CFS demonstrates robust psychometric properties—including structural validity,reliability,and measurement invariance—for its application among Chinese middle school students.
基金Supported by the National Natural Science Foundation of China(42172166)National Natural Science Foundation and CNPC Joint Fund Project(U23B20154)CNPC-Southwest Petroleum University Science and Technology Cooperation Project(2020CX010000).
文摘This paper discusses the characteristics and formation mechanism of thin dolomite reservoirs in the lower submember of the second member of the Permian Maokou Formation(lower Mao 2 Member)in the Wusheng-Tongnan area of the Sichuan Basin,SW China,through comprehensive analysis of geological,geophysical and geochemical data.The reservoir rocks of the lower Mao 2 Member are dominated by porphyritic vuggy dolomite and calcareous dolomite or dolomitic limestone,which have typical karst characteristics of early diagenetic stage.The dolomites at the edge of the karst system and in the fillings have dissolved estuaries,and the dolomite breccia has micrite envelope and rim cement at the edge,indicating that dolomitization is earlier than the early diagenetic karstification.The shoal facies laminated dolomite is primarily formed by the seepage reflux dolomitization of moderate-salinity seawater.The key factors of reservoir formation are the bioclastic shoal deposition superimposed with seepgae reflux dolomitization and the karstification of early diagenetic stage,which are locally reformed by fractures and hydrothermal processes.The development of dolomite vuggy reservoir is closely related to the upward-shallowing sequence,and mainly occurs in the late highstand of the fourth-order cycle.Moreover,the size of dolomite is closely related to formation thickness,and it is concentrated in the formation thickness conversion area,followed by the thinner area.According to the understanding of insufficient accommodation space in the geomorphic highland and the migration of granular shoal to geomorphic lowland in the late highstand of the third-order cycle,it is proposed that the large-scale shoal-controlled dolomite reservoirs are distributed along structural highs and slopes,and the reservoir-forming model with shoal,dolomitization and karstification jointly controlled by the microgeomorphy and sea-level fluctuation in the sedimentary period is established.On this basis,the paleogeomorphology in the lower Mao 2 Member is restored using well-seismic data,and the reservoir distribution is predicted.The prediction results have been verified by the latest results of exploration wells and tests,which provide an important reference for the prediction of thin dolomite reservoirs under similar geological setting.
基金supported by the Sichuan Provincial Cadre Health Research Project(ZH2024-101)the Key Natural Science Foundation of Sichuan Province(No.2025 ZNSFSC0053)。
文摘BACKGROUND Solid fuel use for cooking and heating is a major environmental risk factor,yet its association with new-onset heart disease(HD)remains unclear.The aim of this study was to investigate the relationship between solid fuel exposure and new-onset HD in a large cohort.METHODS Multivariable logistic regression models assessed associations between cooking/heating fuel types(coal,crop residue/wood,liquefied petroleum gas,natural gas,and others)and new-onset HD.Subgroup analyses explored effect modification by age,sex,education,smoking,alcohol use,and region.RESULTS A prospective cohort study included 5915 participants,with 781 participants(13.2%)developing new-onset HD.Coal use for cooking showed an initial association with new-onset HD risk(OR=1.41,95%CI:1.06–1.86,P=0.02),which attenuated after full adjustment(OR=1.28,95%CI:0.96–1.72,P=0.10).Coal use for heating demonstrated robust associations across all models(OR=1.86,95%CI:1.42–2.43,P<0.001).Crop residue/wood burning for heating was also significant(Model 2:OR=1.40,95%CI:1.06–1.86,P=0.02).Subgroup analyses revealed stronger associations among females,non-smokers,non-drinkers,and less-educated participants.Geographic stratification showed significant associations in southern but not northern regions.CONCLUSIONS Solid fuel use,particularly coal for heating,is associated with increased new-onset HD risk.Reducing solid fuel exposure is crucial for HD prevention in low-resource settings.
文摘Background: Chronic low back pain is a leading cause of morbidity and disability globally. Low and Middle-Income Countries (LMICs) tend to be more affected, with chronic low back pain (CLBP) being among the leading presenting complaints at specialist consultation. The exact burden of this disease is sparingly known in our setting. Objective: To evaluate the burden of chronic low back pain at the Yaounde Central Hospital. Methods: This was a descriptive cross-sectional study for a period of 3 months, from March 2022 to May 2022. After obtaining ethical clearance and research authorisations, data was collected using structured questionnaires from patients with chronic low back pain presenting at the Yaounde Central Hospital during the aforementioned time frame. This data was then tabulated with the Statistical Package for Social Sciences (SPSS 23.0), and disability was assessed using the modified Roland Morris Disability Questionnaire and the Oswestry Disability Index. Data analysis was done using the International Business Machines Statistical Package for Social Sciences (IBM-SPSS) VERSION 23.0. Results: 115 cases of CLBP were included. The mean age was 52.62 years, and the sex ratio was 0.3. The average monthly income was less than 50,000 frs CFA, in 37.4% of cases. In 57.9%, patients had a job that involved physical labour. The patients had a secondary level of education in 40.9%, and alcohol consumption was observed in 36%. The average number of days of a work stoppage due to LBP was 12.75 days (±12SD), and the median duration of CLBP was 7.15 (7.5SD) years. The median pain intensity was 7 (±2SD), with leg pain and sensory neuropathy observed in 67.8% and 63.5% respectively. Lumbar X-ray was done in 45.2% and revealed lumbar osteoarthrosis in 62.4%. Hypertension as a comorbidity was observed in 26.1%. Medical treatment was used at least once in 98.3% of cases. The average cost of management per month was assessed, and the median was 52,000 FCFA (±20,876 SD). Using the Oswestry Disability Questionnaire, 46 patients, that is 40% of the study population, were classified as severely disabled with a median ODI score of 40%. The factors which were independently associated with disability were level of education, alcohol consumption, treatment modality, pain intensity, body mass index (BMI), psychological wellbeing and number of sick leave days. Conclusion: Chronic low back pain is common in our setting. There is a female predominance with the mean age of the study population situated in the 5th decade. Low-income earners and patients with a job involving physical labour were the most affected. Medical treatment was the main therapeutic modality, with the average cost of management per month being above the average monthly income of the greater majority of the patients. Several factors influenced disability, some of which were independently associated with it, such as level of education, alcohol consumption and treatment modality.
基金supported by the National Natural Science Foundation of China(Grant No.41601317)"14th Five Year Plan"For Education Sciences Planning of Shanxi Province(Grant No.SZH-230067)Ideological and Political Courses at Shanxi Normal University(2023KCSZ-15)。
文摘Drought is an important disaster factor disturbing the stability of the ecosystem in the middle reaches of the Yellow River(YRM).In this study,the spatiotemporal distribution of drought in the YRM from 2000 to 2021 was quantitatively investigated by constructing the TVPDI(Temperature-VegetationPrecipitation Dryness Index),and its driving mechanism was explored.The results show that:(1)a significant decreasing trend was observed in the regional annual TVPDI of the YRM,while the autumn TVPDI index showed an increasing trend during 2000-2021.(2)Plants are more susceptible to drought during the growing season.(3)Drought in YRM showed significant spatial heterogeneity,and the high gully area in the Loess Plateau and the earth-rocky mountain areas were less affected by drought than other regions.(4)The Structural Equation Model(SEM)indicated that regional soil moisture and vegetation coverage have a direct influence on regional TVPDI variation.This study has explored the regional differences of drought in different seasons and landforms in the YRM,providing a basis for carrying out targeted seasonal ecological management and refining regional environmental governance,as well as a reference for formulating differentiated ecological restoration and water resource allocation strategies according to local conditions.
基金National Natural Science Foundation of China,No.41907382China Postdoctoral Science Foundation,No.2019M652520Henan Postdoctoral Science Foundation,No.201902025。
文摘This paper selects sampling sections for the mainstream and tributaries of the middle and lower reaches of the Yellow River,collects river water and sediment samples during the flood season for pollen analysis,and uses methods such as Geodetector to explore the distribution characteristics and influencing factors of pollen.The results show significant variations in vegetation composition across different watersheds,leading to notable differences in both the percentage and concentration of pollen types.Pollen concentration in river water is generally higher in the mainstream compared to tributaries,while sediment pollen percentage and concentration are typically lower in the mainstream than in tributaries.The concentration of suspended solids is the most significant factor affecting pollen concentration in the Yellow River,with this effect being particularly prominent outside the Shanxi-Shaanxi Gorge.Abundant coarse sand and rapid flow velocities are likely responsible for the high suspended solids concentration and lower pollen concentration observed in the mainstream of the Shanxi-Shaanxi Gorge.In sediments,clay content is the primary factor influencing pollen concentration,and its interaction with silt and flow velocity has a more prominent influence on pollen concentration.At the Yellow River section below the Shanxi-Shaanxi Gorge,sediment pollen and clay concentrations significantly increase.The changes in pollen concentration in the river water before and after the reservoir are consistent with the suspended solids concentration,while the changes in sediment pollen concentration are consistent with the clay content.Notably,pollen concentrations in sediments decrease more significantly after passing through a reservoir compared to changes observed in river water samples.Overall,there is a strong correlation between river pollen and topsoil pollen,which can provide a reliable reflection of the broader vegetation landscape of the watershed.The findings can provide support for paleoenvironmental reconstruction using pollen from alluvial sediments or lakes with river inflows.
基金funded by the Department of Biotechnology,Ministry of Science and Technology,Government of India(DBT)under grant number ADMaC DBT-NER/LIVS/11/2012.
文摘We report the development of a triplex nucleic acid lateral flow immunoassay(NALFIA)for the detection of the genomes of Nipah virus(NiV),Middle East respiratory syndrome coronavirus(MERS-CoV)and Reston ebolavirus(REBOV),which are intended for screening bats as well as other hosts and reservoirs of these three viruses.Our triplex NALFIA is a two-step assay format:the target nucleic acid in the sample is first amplified using tagged primers,and the tagged dsDNA amplicons are captured by antibodies immobilized on the NALFIA device,resulting in signal development from the binding of a streptavidin-colloidal gold conjugate to a biotin tag on the captured amplicons.Triplex amplification of the N gene of NiV,the UpE gene of MERS-CoV,and the Vp40 gene of REBOV was optimized,and three compatible combinations of hapten labels and antibodies were identified for end point detection.The lowest RNA copy numbers detected by the triplex NALFIA were 8.21e4 for the NiV N target,7.09e1 for the MERS-CoV UpE target,and 1.83e4 for the REBOV Vp40 target.Using simulated samples,the sensitivity and specificity for MERS-CoV and REBOV targets were estimated to be 100%,while the sensitivity and specificity for the NiV target were 91%and 93.3%,respectively.The compliance rate between triplex NALFIA and real-time RT‒PCR was 92%for the NiV N target and 100%for the MERS-CoV UpE and REBOV Vp40 targets.
基金Under the auspices of the National Natural Science Foundation of China(No.42277354,U2243211)Fundamental Research Funds for the Hebei University of Water Resources and Electric Engineering(No.SYKY2113)Science Research Project of Hebei Education Department(No.QN2025293)。
文摘Changes in river cross-section morphology have decisive influences on the flood discharge and sand transport capacity of rivers;thus,these changes strongly reflect the vitality of a river.In this paper,based on the river cross-section and water and sediment data of two different periods(1974−1987 and 2007−2021),the trend analysis,change-point analysis and sediment rating curve method were used to analyze the change process of river cross-section morphology and its response to streamflow and sediment changes in the main river stream of the Yellow River at the Longmen hydrological station.From 1974 to 1987(except in 1977),the riverbed experi-enced siltation,and the riverbed elevation rose.Conversely,from 2007 to 2021,the riverbed experienced scouring,and the riverbed el-evation gradually decreased.The cross-section shape changed from rectangular to U-shaped(deeper on the right side)at the Longmen cross-section.The changes in streamflow and sediment processes significantly impacted the evolution of river cross-section.Stream-flow(P<0.05),sediment discharge(P<0.01),and the sediment load coefficients(P<0.01)decreased significantly.The relationship between the water depth and sediment load coefficients followed a power function.The decreasing trend in sediment discharge was sig-nificantly stronger than that in streamflow.Suspended sediment particles tended to become finer.The sediment rating curve indicates that the sediment supply from upstream decreased while the erosive power in the river channel increased,leading to a gradual decline in riverbed elevation at the Longmen cross-section from 2007 to 2021.These findings help us better understand the impacts of ecological restoration on changes in river streamflow and sediment during river evolution.
基金Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004)National Natural Science Foundation of China(42175061)。
文摘Studying the causes of summer(June–July–August)precipitation anomalies in the middle and lower reaches of the Yangtze River(MLYR)and accurately predicting rainy season precipitation are important to society and the economy.In recent years,the sea surface temperature(SST)trend factor has been used to construct regression models for summer precipitation.In this study,through correlation analysis,winter SST anomaly predictors and the winter Central Pacific SST trend predictor(CPT)are identified as closely related to the following MLYR summer precipitation(YRSP).CPT can influence YRSP by inducing anomalous circulations over the North Pacific,guiding warm and moist air northward,and inhibiting the development of the anomalous anticyclone over the Northwest Pacific.This has improved the predictive skill of the seasonal regression model for YRSP.After incorporating the CPT,the correlation coefficient of the YRSP regression model improved by 40%,increasing from 0.45 to 0.63,and the root mean squared error decreased by 22%,from 1.15 to 0.90.
文摘By means of MICAPS data from China Meteorological Administration,the weather dynamics causing precipitation enhancement in the middle and lower Yangtze Valley on January 19,2008 was analyzed.The results showed that the convergence of cold and warm air was the basic condition of precipitation enhancement,and the influence systems of precipitation enhancement were surface inverse trough,850-700 hPa warm shear and 850-500 hPa low trough,while southwest and southeast low jet were the important dynamic mechanisms of precipitation enhancement,and southwest low jet offered abundant water vapor for precipitation enhancement.
基金This study was supported by the National Natural Science Foundation of China(Grants 4037200140072007+3 种基金49772083 to Dong Xiping)by the Laboratory of Paleobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences(Grant 023106 to Dong Xiping)by the Research Fund for Doctoral Program of High Education(Grant 2000000127 to Dong Xiping)by a travel grant from the Ohio State University(to Stig M.Bergstrom).
文摘Since 1985, samples with a total weight of more than 14,000 kg, mainly from three key sections in western and northwestern Hunan, South China, have been processed for conodonts. In strata older than the late Late Cambrian paraconodonts have proved useful for stratigraphic subdivision and correlation. Thirteen conodont zones are proposed in the Middle Cambrian through lowermost Ordovician. The correlation between these zones and those of North China, western U. S.A., western Newfoundland, Canada, and Iran is discussed. In ascending order, these 13 zones are as follows: The Gapparodus bisulcatus-Westergaardodina brevidens Zone, Shandongodus priscus-Hunanognathus tricuspidatus Zone, Westergaardodina quadrata Zone, Westergaardodina matsushitai-W. grandidens Zone, Westergaardodina lui-W. am Zone, Westergaardodina cf. calix-Prooneotodus rotundatus Zone, Proconodontus tenuiserratus Zone, Proconodontus Zone, Eoconodontus Zone, Cordylodus proavus Zone, Cordylodus intermedius Zone, Cordylodus lindstromi Zone, and Cordylodus angulatus Zone (lower part). The Westergaardodina lui-W. ani and Westergaardodina cf. calix-Prooneotodus rotundatus Zones replace the Westergaardodina proligula and Westergaardodina cf. behrae-Prooneotodus rotundatus Zones, respectively, in the lowermost Upper Cambrian. Two new species (Westergaardodina Iui and Westergaardodina ani) and one conditionally identified species (Westergaardodina cf. calix) are described.
基金Supported by The Ministry of Health Sector Funds of China,No. 201002020
文摘AIM: To study the feasibility and safety of middle segmental pancreatectomy (MSP) compared with pancreaticoduodenectomy (PD) and extended distal pancreatectomy (EDP). METHODS: We studied retrospectively 36 cases that underwent MSP, 44 patients who underwent PD, and 26 who underwent EDP with benign or low-grade malignant lesions in the mid-portion of the pancreas, between April 2003 and December 2009 in Ruijin Hospital. The perioperative outcomes and long-term outcomes of MSP were compared with those of EDP and PD. Periop-erative outcomes included operative time, intraoperative hemorrhage, transfusion, pancreatic fistula, intraabdominal abscess/infection, postoperative bleeding, reoperation, mortality, and postoperative hospital time. Long-term outcomes, including tumor recurrence, newonset diabetes mellitus (DM), and pancreatic exocrine insufficiency, were evaluated. RESULTS: Intraoperative hemorrhage was 316.1 ± 309.6, 852.2 ± 877.8 and 526.9 ± 414.5 mL for the MSP, PD and EDP groups, respectively (P < 0.05). The mean postoperative daily fasting blood glucose level was significantly lower in the MSP group than in the EDP group (6.3 ± 1.5 mmol/L vs 7.3 ± 1.5 mmol/L, P < 0.05). The rate of pancreatic fistula was higher in the MSP group than in the PD group (42% vs 20.5%, P = 0.039), all of the fistulas after MSP corresponded to grade A (9/15) or B (6/15) and were sealed following conservative treatment. There was no significant difference in the mean postoperative hospital stay between the MSP group and the other two groups. After a mean follow-up of 44 mo, no tumor recurrences were found, only one patient (2.8%) in the MSP group vs five (21.7%) in the EDP group developed new-onset insulin-dependent DM postoperatively (P = 0.029). Moreover, significantly fewer patients in the MSP group than in the PD (0% vs 33.3%, P < 0.001) and EDP (0% vs 21.7%, P = 0.007) required enzyme substitution. CONCLUSION: MSP is a safe and organ-preserving option for benign or low-grade malignant lesions in the neck and proximal body of the pancreas.
基金National Natural Science Foundation of China, No. 40331013 No.90502009 No. 40571007, No. 40701021
文摘Based on the long-term precipitation series with annual time resolution in the middle and lower reaches of the Yellow River and its four sub-regions during 1736-2000 reconstructed from the rainfall and snowfall archives of the Qing Dynasty, the precipitation cycles are analyzed by wavelet analysis and the possible climate forcings, which drive the precipitation changes, are explored. The results show that： the precipitation in the middle and lower reaches of the Yellow River has inter-annual and inter-decadal oscillations like 2-4a, quasi-22a and 70-80a. The 2-4a cycle is linked with El Nino events, and the precipitation is lower than normal year in the occurrence of the El Nino year or the next year; for the quasi-22a and the 70-80a cycles, Wolf Sun Spot Numbers and Pacific Decadal Oscillation （PDO） coincide with the two cycle signals. However, on a 70-80a time scale, the coincidence between solar activity and precipitation is identified before 1830, and strong （weak） solar activity is generally correlated to the dry （wet） periods; after 1830, the solar activity changes to 80-100a quasi-century long oscillation, and the adjusting action to the precipitation is becoming weaker and weaker; the coincidence between PDO and precipitation is shown in the whole time series. Moreover, in recent 100 years, PDO is becoming a pace-maker of the precipitation on the 70-80a time scale.
基金National Natural Science Foundation of China, No.51379155, No.51339001, No.51579185 National Key Research Program of China, No.2016YFC0402306, No.2016YFC04022310, No.2016YFC0402106 CentraI Public Research Institutes Fundamental Research, No.TKS 160103
文摘Alluvial channel has always adjusted itself to the equilibrium state of sediment transport after it was artificially or naturally disturbed. How to maintain the equilibrium state of sediment transport and keep the river regime stable has always been the concerns of fluvial geomorphologists. The channel in the middle and lower reaches of the Yangtze River is characterized by the staggered distribution of the bifurcated river and the single-thread river. The change of river regime is more violently in the bifurcated river than in the single-thread river. Whether the adjustment of the river regime in the bifurcated river can pass through the single-thread river and propagate to the downstream reaches affects the stabilities of the overall river regime. Studies show that the barrier river reach can block the upstream channel adjustment from propagating to the downstream reaches; therefore, it plays a key role in stabilizing the river regime. This study investigates 34 single-thread river reaches in the mid- dle and lower reaches of the Yangtze River. On the basis of the systematic summarization of the fluvial process of the middle and lower reaches of the Yangtze River, the control factors of barrier river reach are summarized and extracted： the planar morphology of single-thread and meandering; with no flow deflecting node distributed in the upper or middle part of the river reach; the hydraulic geometric coefficient is less than 4; the longitudinal gradient is greater than 12‰, the clay content of the concave bank is greater than 9.5%, and the median diameter of the bed sediment is greater than 0.158 mm. From the Navier-Stokes equation ,the calculation formula of the bending radius of flow dynamic axis is deduced and then the roles of these control factors on restricting the migration of the flow dynamic axis and the formation of the barrier river reach are analyzed. The barrier river reach is considered Such. When the ratio of the migration force of the flow dynamic boundary is less than 1 under different flow levels axis to the constraint force of the channel boundary is less than 1 under different flow levels.The mechanism of the barrier river reach is such that even when the upstream river regime adjusts, the channel boundary of this reach can always constrain the migration amplitude of the flow dynamic axis and centralize the planar position of the main stream line under different upstream river regime conditions, pro- viding a relatively stable incoming flow conditions for the downstream reaches, thereby blocking the upstream river regime adjustment from propagating to the downstream reaches.
基金supported by the National Natural Science Foundation of China under Grant Nos.40333034,40075007,and 40175002the.Chinese Academy of Sciences under Grant No.KZCX-SW-217.
文摘Recent advances in studies of the middle and upper atmosphere and their coupling with the lower atmosphere in China are briefly reviewed. This review emphasizes four aspects: (1) Development of instrumentation for middle and upper atmosphere observation; (2) Analyses and observation of middle and upper atmosphere; (3) Theoretical and modeling studies of planetary wave and gravity wave activities in the middle atmosphere and their relation to lower atmospheric processes; (4) Study on the coupling between the stratosphere and the troposphere.
基金supported by National Natural Science Foundation of China(No.81201026)
文摘The clinical characteristics of patients who presented in poor clinical grade due to ruptured middle cerebral artery aneurysms （MCAAs） associated with large sylvian hematomas （SylH） were ana- lyzed and an ingenious designed prophylactic hinged craniectomy was introduced. Twenty-eight pa- tients were graded into Hunt-Hess grades IV-V and emergency standard micro-neurosurgeries （aneu- rysm clipping, hematoma evacuation and prophylactic hinged craniectomy） were performed, and their clinical data were retrospectively analyzed. 46.43% of the patients reached encouraged favorable out- comes on discharge. The favorable outcome group and the poor outcome group significantly differed in terms of patients＇ anisocoria, Hunt-Hess grade before surgery, extent of the midline shift and time to the surgery after bleeding （P〈0.05）. There were no significant differences in age, sex, volume and location of the hematoma, size of aneurysm between the favorable and poor groups （P〉0.05）. However, ingen- ious designed prophylactic hinged craniectomy efficiently reduced the patients＇ intracranial pressure （ICP） after surgery. It was suggested that preoperative conditions such as Hunt-Hess grading, extent of the midline shift and the occurrence of cerebral hernia affect the prognosis of patients, but time to the surgery after bleeding and prophylactic hinged craniectomy are of significant importance for optimizing the prognosis ofMCAA oatients 19resenting with large SylH.
基金supported by the National Natural Science Foundation of China (Grant No. 40930419)the National Special Research Programs for Non-Profit Trades (Sponsored by MLR, Grant Nos. 200911007 and 200811114)Open Foundation of State Key laboratory of Geological Processes and Mineral Resources, School of the Earth Sciences and Resources, China University of Geosciences, Beijing (Grant No. GPMR201029)
文摘Late Mesozoic volcanic-subvolcanic rocks and related iron deposits, known as porphyry iron deposits in China, are widespread in the Ningwu ore district （Cretaceous basin） of the middle-lower Yangtze River polymetallic ore belt, East China. Two types of Late Mesozoic magmatic rocks are exposed： one is dioritic rocks closely related to iron mineralization as the hosted rock, and the other one is granodioritic （-granitic） rocks that cut the ore bodies. To understand the age of the iron mineralization and the ore-forming event, detailed zircon U-Pb dating and Hf isotope measurement were performed on granodioritic stocks in the Washan, Gaocun-Nanshan, Dongshan and Heshangqiao iron deposits in the basin. Four emplacement and crystallization （typically for zircons） ages of granodioritic rocks were measured as 126.1±0.5 Ma, 126.8±0.5 Ma, 127.3±0.5 Ma and 126.3±0.4 Ma, respectively in these four deposits, with the LA-MC-ICP-MS zircon U-Pb method. Based on the above results combined with previous dating, it is inferred that the iron deposits in the Ningwu Cretaceous basin occurred in a very short period of 131-127 Ma. In situ zircon Hf compositions of εHf（t） of the granodiorite are mainly from -3 to -8 and their corresponding 176Hf/177Hf ratio are from 0.28245 to 0.28265, indicating similar characteristics of dioritic rocks in the basin. We infer that granodioritic rocks occurring in the Ningwu ore district have an original relationship with dioritic rocks. These new results provide significant evidence for further study of this ore district so as to understand the ore-forming event in the study area.
基金supported by the National Natural Science Foundation of China,No.81871841(to YLB) and No.81772453(to DSX)
文摘Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.However,the molecular mechanism underlying its efficacy remains unclear.In this study,a middle cerebral artery occlusion(MCAO)rat model was produced by the suture method.Rats received modified constraint-induced movement therapy 1 hour a day for 14 consecutive days,starting from the 7^th day after middle cerebral artery occlusion.Day 1 of treatment lasted for 10 minutes at 2r/min,day 2 for 20 minutes at 2 r/min,and from day 3 onward for 20 minutes at 4 r/min.CatWalk gait analysis,adhesive removal test,and Y-maze test were used to investigate motor function,sensory function as well as cognitive function in rodent animals from the 1st day before MCAO to the 21^st day after MCAO.On the 21^st day after MCAO,the neurotransmitter receptor-related genes from both contralateral and ipsilateral hippocampi were tested by micro-array and then verified by western blot assay.The glutamate related receptor was shown by transmission electron microscopy and the glutamate content was determined by high-performance liquid chromatography.The results of behavior tests showed that modified constraint-induced movement therapy promoted motor and sensory functional recovery in the middle cerebral artery-occluded rats,but had no effect on cognitive function.The modified constraint-induced movement therapy upregulated the expression of glutamate ionotropic receptor AMPA type subunit 3(Gria3)in the hippocampus and downregulated the expression of the beta3-adrenergic receptor gene Adrb3 and arginine vasopressin receptor 1 A,Avprla in the middle cerebral artery-occluded rats.In the ipsilateral hippocampus,only Adra2 a was downregulated,and there was no significant change in Gria3.Transmission electron microscopy revealed a denser distribution the more distribution of postsynaptic glutamate receptor 2/3,which is an a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor,within 240 nm of the postsynaptic density in the contralateral cornu ammonis 3 region.The size and distribution of the synaptic vesicles within 100 nm of the presynaptic active zone were unchanged.Western blot analysis showed that modified constraint-induced movement therapy also increased the expression of glutamate receptor 2/3 and brain-derived neurotrophic factor in the hippocampus of rats with middle cerebral artery occlusion,but had no effect on Synapsin I levels.Besides,we also found modified constraint-induced movement therapy effectively reduced glutamate content in the contralateral hippocampus.This study demonstrated that modified constraint-induced movement therapy is an effective rehabilitation therapy in middle cerebral artery-occluded rats,and suggests that these positive effects occur via the upregulation of the postsynaptic membrane a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor expression.This study was approved by the Institutional Animal Care and Use Committee of Fudan University,China(approval No.201802173 S)on March 3,2018.
