According to low earth orbit（LEO） satellite systems with users of different levels, a dynamic channel reservation scheme based on priorities is proposed. Dynamic calculation of the thresholds for reserved channels i...According to low earth orbit（LEO） satellite systems with users of different levels, a dynamic channel reservation scheme based on priorities is proposed. Dynamic calculation of the thresholds for reserved channels is the key of this strategy. In order to obtain the optimal thresholds, the traffic is predicted based on the high-speed deterministic movement property of LEO satellites firstly. Then, a channel allocation model based on Markov is established. Finally, the solution of the model is obtained based on the genetic algorithm. Without user location, this strategy effectively reduces handover failures and improves channel utilization by adjusting dynamically the thresholds according to traffic conditions. The simulation results show that the system＇s overall quality of service can be improved by this strategy.展开更多
In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multipl...In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multiplexing systems. During the SCR procedure, only the element with the maximal amplitude is picked for processing, which not only decreases the algorithm complexity, but also helps to overcome the BER deterioration. With the LSA method, the amplitude of the peak-cancelling signals can approximate to that of the original clipping noise as much as possible. Through the combination of the optimization factor in the LSA method, the classic SCR method can achieve better PAPR reduction with faster convergence. Simulation results show that the proposed SCR-LSA TR scheme has less in-band distortion and smaller out-of-band spectral radiation. The BER of the proposed scheme shows a better performance especially under the 16-QAM over the additive white Gaussian noise channel.展开更多
Call admission control (CAC) and resource reservation (RR) for mobile communication are two important factors that guarantee system efficiency and quality of service (QoS) required for different services in a very sca...Call admission control (CAC) and resource reservation (RR) for mobile communication are two important factors that guarantee system efficiency and quality of service (QoS) required for different services in a very scarce resource as the radio spectrum. A new scheme was proposed which extends the concepts of resource sharing and reservations for wideband code division multiple access (WCDMA) systems with a unique feature of soft capacity. Voice and data traffic were considered. The traffic is further classified into handoff and new requests. The reservation thresholds were dynamically adjusted according to the traffic pattern and mobility prediction in order to achieve the maximum channel utilization, while guaranteeing different QoS constraints. The performance of proposed scheme was evaluated using Markov models. New call blocking probability, handoff call dropping probability, and channel utilization were used as benchmarks for the proposed scheme.展开更多
Ovarian aging is characterized by a progressive decline in oocyte quality and quantity with age.Icariin(ICA),a flavonoid compound derived from Epimedium species,has demonstrated potential as an agent for ovarian resto...Ovarian aging is characterized by a progressive decline in oocyte quality and quantity with age.Icariin(ICA),a flavonoid compound derived from Epimedium species,has demonstrated potential as an agent for ovarian restoration.In this study,a subcutaneous implantation system using gelatin methacryloyl(GelMA)hydrogel embedded with ICA was developed to restore ovarian function in aged female mice.Mice were assigned to receive subcutaneous implantation of GelMA alone(GelMA group),GelMA containing ICA(GelMA/ICA group),or a sham operation.Ovarian morphology,serum hormone levels,follicle counts across developmental stages,and reproductive outcomes were evaluated.In vitro fertilization(IVF)and embryo culture assays were performed to assess oocyte developmental potential,while a 10 day natural mating trial was conducted to determine fertility restoration.RNA sequencing(RNA-seq)and RT-qPCR were performed to elucidate the underlying molecular mechanisms.Results showed that GelMA/ICA treatment significantly increased ovarian index(0.19±0.01 vs.0.13±0.01,P<0.0001)and follicle numbers at all developmental stages,including primordial(383.33±151.65 vs.107.14±32.26,P<0.0001),primary(203.33±83.22 vs.91.43±27.04,P=0.003),and secondary follicles(154.17±52.00 vs.59.28±20.50,P=0.029)compared to the sham controls.Hormonal analyses revealed a significant reduction in serum follicle-stimulating hormone(FSH,11.97±3.53 vs.53.10±17.89 ng/mL,P=0.0008),accompanied by elevated anti-Müllerian hormone(AMH,22.97±2.26 vs.5.54±1.56 ng/mL,P<0.0001)and estradiol(E2,315.30±37.62 vs.168.5±14.78 pg/mL,P<0.0001).Oocyte yield and developmental potential improved significantly,as reflected by the increased number of superovulated MII oocytes(17.83±5.15 vs.4.83±4.79,P=0.0002),and higher proportions of two-cell(85.90%±6.16%vs.50.00%±10.00%,P=0.0009),four-cell(81.67%±9.76%vs.50.00%±10.00%,P=0.0061),and blastocyst stage embryos(64.25%±10.55%vs.23.33%±15.28%,P=0.0067).Live birth numbers were significantly increased following GelMA/ICA treatment(6.90±3.21 vs.1.72±2.05,P=0.0001).Transcriptomic analysis revealed up-regulation of genes associated with cytoskeletal organization(Vil1,Tubb3),lipid storage(Soat2,Plin4),oocyte maturation(Oosp2),and cytokine secretion(Cxcl12).Collectively,these findings suggest that GelMA/ICA hydrogels effectively reverse key hallmarks of ovarian aging and restore reproductive function in aged mice,offering a promising platform for fertility preservation and a novel therapeutic for future investigations into ovarian aging.展开更多
Accurately forecasting ecosystem services is critical for enhancing our understanding and improving management practices within nature reserves,particularly in light of climate change,land use/cover changes,and their ...Accurately forecasting ecosystem services is critical for enhancing our understanding and improving management practices within nature reserves,particularly in light of climate change,land use/cover changes,and their complex interactions.However,existing studies often fail to fully consider vegetation response,constituting a gap in the comprehensive assessment of changes in ecosystem services.Therefore,a coupled model framework integrating climate change,land use change,and vegetation dynamics was developed to allow for the simulation of dynamic ecosystem service scenarios throughout the twenty-first century.The Jiulianshan National Nature Reserve in Jiangxi Province was considered as the study area.The results showed that ecosystem services and their synergistic effects will be optimized under scenarios that emphasize strict protection of ecological lands and incorporating the SSP1-2.6 scenario.However,sustaining optimized ecosystem services poses significant challenges in scenarios characterized by resource-intensive development and ongoing climate warming,as in the SSP5-8.5 scenario.Notably,discernible variations exist in balancing and synergizing the management of ecosystem services across diverse land uses and forest types.Our study underscores the importance of integrating vegetation response into the framework of ecosystem service forecasting,which is essential for assisting nature reserves in effectively addressing the multifaceted risks associated with climate change and rapid socio-economic development.展开更多
Agricultural land development is a pivotal strategy for addressing the global food security crisis.Barren grassland,especially those in mountainous regions,constitutes critical areas where cultivation can substantiall...Agricultural land development is a pivotal strategy for addressing the global food security crisis.Barren grassland,especially those in mountainous regions,constitutes critical areas where cultivation can substantially enhance land resources.This study highlights the necessity for a precise correlation between land development initiatives and constraints in order to optimize efficiency and enhance the effectiveness of such projects,with the core being the seamless integration of land development engineering and techniques to eliminate agricultural constraints.This study employs a systems engineering approach to classify improvement factors into mobile and fixed categories,elucidating the integration methods of constraint factors.Adhering to the Wooden Barrel Principle,these constraints were rigorously analyzed based on soil quality,land topography,water availability,and agricultural infrastructure.An innovative method of engineering type combination is proposed,which effectively explains the correlation between natural factors combination,project type combination,and target factors combination.It provides a convenient way for the selection of barren grassland development projects and lays a foundation for land planning,development project establishment,program selection,engineering design,and budget preparation.Taking Tang County of China as an example,it is divided into 19 factor improvement areas,a quick reference table of engineering types is established,and 14 main types of engineering combinations are obtained,which lays a foundation for the application of theoretical framework in practice.展开更多
Objective: To compare the functional outcomes of patients who had parotid masseter fascia reserved and unreserved flap elevating scheme in parotidectomy, especially the morbidity of Frey's syndrome. Methods: Twent...Objective: To compare the functional outcomes of patients who had parotid masseter fascia reserved and unreserved flap elevating scheme in parotidectomy, especially the morbidity of Frey's syndrome. Methods: Twenty-three patients (group A) had parotid masseter fascia reserved in the parotidectomy, 32 patients (group B) had parotid masseter fascia unreserved in the operation. Compare the morbidity of gustatory sweating syndrome of the two groups. Results: Follow-up after 6 months to 2.5 years, gustatory sweating syndrome occurred in 4 patients of group A (17%), 17 patients in group B (57%). Conclusion: Reservation technic of the parotid masseter fascial in parotidectomy could prevent regeneration of parasympathetic nerve and thus prevent Frey's syndrome post-operation.展开更多
This paper had described the influence of restoration and reservation of Xi'an Qujiang Pond Ruins Park on urban landscape with an emphasis,proposed to promote urban landscape development by making use of cultural ...This paper had described the influence of restoration and reservation of Xi'an Qujiang Pond Ruins Park on urban landscape with an emphasis,proposed to promote urban landscape development by making use of cultural ruins. It analyzed the good and bad effects of Xi'an Qujiang Pond Ruins Park on urban landscape and concluded that cultural ruins should be used to shape new outlook of urban landscape,so as to discuss the momentous significance of cultural ruins in urban landscape.展开更多
[Objective] The aim was to explore the spatial and temporal distribution characteristics of wind energy resource and preservation in central and west area of Hexi Corridor. [Method] By dint of the wind speed data from...[Objective] The aim was to explore the spatial and temporal distribution characteristics of wind energy resource and preservation in central and west area of Hexi Corridor. [Method] By dint of the wind speed data from 1955 to 2007 in ten meteorological observation station in central and west area of Hexi Corridor,and special wind tower fine data from January to December in 2007,the distribution and reserves of the region＇s wind energy resources were studied. [Result] The results showed that environmental wind speed was relatively stable in central and west Hexi Corridor. There were no distinct changes in climate characteristics distribution. There were regional differences in the distribution of wind energy,and there was a large numerical area of wind energy in Gazhou County and Yumen City; Wind energy in the region generally was higher. The wind energy density was above 100 w/m2 in the 10 m layer,around 140 w/m2 in most places,and was more than 200 w/m2 in the large number area. The wind grew in vertical direction along with the linear growth of height. Each 10 m high wind increased to 15 w/m2 averagely,50m layer wind energy was greater than the general 240 w/m2 and there were obvious changes on daily and annual with wind energy in central and west area of Hexi Corridor. The duration from March to May was a wind energy-intensive stage,10m height from the ground in the wind around 10：00 in low-value. After growing from 11：00,it met the day largest number at 18：00,and then reduced gradually. Effective wind speed hours in the region in general were more than 6 200 h,and the value in the large areas was close to 7 600 h. [Conclusion] The study laid basis for the development and application of wind energy in central and west area of Hexi Corridor.展开更多
[Objective] The aim was to explore the effects of cultivation and seed reservation methods on quality and disease/insect damages of maca seed in cold highland areas,providing scientific references for cultivation and ...[Objective] The aim was to explore the effects of cultivation and seed reservation methods on quality and disease/insect damages of maca seed in cold highland areas,providing scientific references for cultivation and seed reservation and planning of maca vareity.[Method] Yellow,purple and black maca were selected and cultivated in the region with an elevation of 3 000 m to be experimental materials and cultivation and seed reservation methods were as follows：maca seed reservation in situ,seed reservation in original soils maca grown after selection of maca balls,and seed reservation in the region with an elevation of 2 700 m after selection of maca ball,seed reservation in greenhouses in the region with an elevation of 2 400 m after selection of maca ball,and growing selected balls in greenhouses and transplanting to the farmlands with an elevation of 2 400 m.[Result] The cultivation and seed reservation methods had significant or extremely significant effects on maca phenological phase;maca in different colors were treated by different cultivation and seed reservation methods,showing insignificant effects on disease and insect damages.[Conclusion] It can be concluded that the selected maca balls stored for 15 d as per the method grown in the region with an elevation of 2 700 m will improve seed quality and reduce disease or insect damages.展开更多
[Objective] The aim is to conduct systematic diagnoses on the eco-vulnerability in Daqinggou National Natural Reserve. [Method] A kind of ＂problem pile＂ is proposed about 58 interrelated problems of ecological vulne...[Objective] The aim is to conduct systematic diagnoses on the eco-vulnerability in Daqinggou National Natural Reserve. [Method] A kind of ＂problem pile＂ is proposed about 58 interrelated problems of ecological vulnerability by field survey and questionnaires and a ladder diagram of interrelations among the problems is established. The root problems, basic problems, core problems, interrelation and solving approaches are proposed, as well. [Result] It can be concluded from system diagnosis that fragile ecosystem of the Reserve can be observed from poor disasterresistibility, lower species diffusivity, lower system metabolism and poor system restorability. According to system diagnoses, management planning and control subsystem is key for protection of system vulnerability and solving different problems in process-oriented system. Conservation of the Reserve and ecological education on tourists are indispensible. It can be concluded from diagnoses that plant updating, evolution and ill growth in the Reserve are the focus of the vulnerable ecosystem, which influence species diffusivity, system metabolism and restorability and constitute central nodes of process-oriented and effect-oriented subsystems. [Conclusion] The research provides references for solving vulnerability issues of conservation and tourism management in Daqinggou National Nature Reserve.展开更多
The concept of the brain cognitive reserve is derived from the well-acknowledged notion that the degree of brain damage does not always match the severity of clinical symptoms and neurological/cognitive outcomes.It ha...The concept of the brain cognitive reserve is derived from the well-acknowledged notion that the degree of brain damage does not always match the severity of clinical symptoms and neurological/cognitive outcomes.It has been suggested that the size of the brain(brain reserve) and the extent of neural connections acquired through life(neural reserve) set a threshold beyond which noticeable impairments occur.In contrast,cognitive reserve refers to the brain's ability to adapt and reo rganize stru cturally and functionally to resist damage and maintain function,including neural reserve and brain maintenance,resilience,and compensation(Verkhratsky and Zorec,2024).展开更多
Elk are seen at the Tian’ezhou National Nature Reserve for Elk in Shishou,Hubei Province,on 27 November 2025.The reserve’s elk population has risen from just 64 in the 1990s to more than 4,500 today.
CHINA.Dinghu Mountain National Nature Reserve.Located in Zhaoqing,Guangdong Province,Dinghu Mountain National Nature Reserve is a pristine natural sanctuary spanning 1,133 hectares within the low mountain ranges of th...CHINA.Dinghu Mountain National Nature Reserve.Located in Zhaoqing,Guangdong Province,Dinghu Mountain National Nature Reserve is a pristine natural sanctuary spanning 1,133 hectares within the low mountain ranges of the Dayunwu Mountains.展开更多
Two representative zones in Chongming Dongtan which faced the Yangtze River and East China Sea respectively were selected to study the variability of soil organic carbon （SOC） reservation capability between coastal ...Two representative zones in Chongming Dongtan which faced the Yangtze River and East China Sea respectively were selected to study the variability of soil organic carbon （SOC） reservation capability between coastal wetland and riverside wetland in the Chongming Dongtan wetland as well as its mechanism by analyzing soil characteristics and plant biomass.The results showed the SOC content of riverside wetland was only 48.61% （P=0.000 〈 0.05） that of coastal wetland.As the organic matter inputs from plant litter of the coastal wetland and riverside wetland were approximately the same,the higher soil microbial respiration （SMR） of riverside wetland led to its lower SOC reservation capability.In the riverside wetland,the high soil microbial biomass,higher proportion of β-Proteobacteria,which have strong carbon metabolism activity and the existence of some specific aerobic heterotrophic bacteria such as Bacilli and uncultured Lactococcus,were the important reasons for the higher SMR compared to the coastal wetland.There were additional differences in soil physical and chemical characteristics between the coastal wetland and riverside wetlands.Path analysis of predominant bacteria and microbial biomass showed that soil salinity influenced β-Proteobacteria and microbial biomass most negatively among these physical and chemical factors.Therefore the low salinity of the riverside area was suitable for the growth of microorganisms,especially β-Proteobacteria and some specific bacteria,which led to the high SMR and low SOC reservation capability when compared to the coastal area.展开更多
BACKGROUND:Whether a major liver resection is safe has been judged mainly from the patient’s hepatic reserve.However,a safe limit for liver resection does not exist yet.This study aimed to construct a new scoring sys...BACKGROUND:Whether a major liver resection is safe has been judged mainly from the patient’s hepatic reserve.However,a safe limit for liver resection does not exist yet.This study aimed to construct a new scoring system as a guide to determine a safe limit for liver resection and avoid liver dysfunction after hepatectomy.METHODS:Eighty-six patients with hepatocellular carcinoma who had undergone hepatectomy in West China Hospital from March 2007 to June 2010 were reviewed.The patients were classified according to the levels of total bilirubin after hepatectomy and the parameters in the perioperative period were compared.Receiver operating characteristic (ROC) analysis was made to assess the liver function compensatory (LFC) value to predict liver dysfunction of the patients after hepatectomy.LFC value is defined as the preoperative KICG value×22.487+standard remnant liver volume (SRLV)×0.020.RESULTS:Patients were classified into group Ⅰ (normal group,n=69) and group Ⅱ (with total bilirubin >85.5 μmol/L for 7 days after hepatectomy,n=17) based on the levels of total bilirubin after hepatectomy.Group II was further divided into two subgroups:recovered subgroup (n=14) and fatal subgroup (n=3).There were no significant differences in preoperative data or intraoperative findings except the indocyanine green test parameters (KICG and ICG R15) and SRLV.ROC analysis showed that the sensitivity and specificity of an LFC value ≤13.01 were 94.1% and 82.6% respectively for predicting liver dysfunction of the patients after hepatectomy.CONCLUSIONS:The LFC value appears to be a good predictor of postoperative liver dysfunction in patients who undergo hepatectomy for HCC.An expected LFC value of 13.01 seems to be a safe limit for liver resection.展开更多
BACKGROUND As transjugular intrahepatic portosystemic shunt(TIPS)creation alters the hemodynamic status of the portal system,whether reduced portal blood supply affects the synthetic reserve function of the liver has ...BACKGROUND As transjugular intrahepatic portosystemic shunt(TIPS)creation alters the hemodynamic status of the portal system,whether reduced portal blood supply affects the synthetic reserve function of the liver has been the focus of clinical attention.Since the Viatorr stent entered the Chinese market in 2015,it has not yet been widely used in clinical practice.Further,unlike other countries,the main cause of liver cirrhosis in China is viral hepatitis.Therefore,use of the Viatorr stent to establish a TIPS channel in patients with liver cirrhosis with differing etiologies is of great clinical interest.AIM To investigate factors affecting changes in liver reserve function after TIPS Viatorr stent implantation.METHODS Clinical data from 200 patients with cirrhotic portal hypertension who received TIPS treatment from March 2016 to March 2020 were analyzed retrospectively.The patients were divided into three groups(A-C),according to their disease etiology,with post-hepatitis,autoimmune,and alcoholic cirrhosis,respectively.Preoperative and postoperative liver and renal function and coagulation data,Child-Pugh grade,and model for end-stage liver disease(MELD)scores were collected.Statistical analyses were performed using the t-test or chi-square test.The incidence and of hepatic encephalopathy and patient survival were calculated using Kaplan-Meier method.RESULTS The surgical success rate was 100%,with mean portal pressure gradient(mmHg)decreasing from 25.5±5.22 to 10.04±2.76(t=45.80;P<0.001).After 24 mo,the cumulative incidence of hepatic encephalopathy in group A was significantly lower than that in group B/C,while the cumulative survival rate was significantly higher in group A than in group B/C(P<0.05 for both).The Child-Pugh score for group A was 6.96±1.21,which was significantly better than those of groups B(7.42±0.99;t=-2.44;P=0.016)and C(7.52±1.12;t=-2.67;P=0.009).Further,the MELD score for group A(9.62±2.19)was significantly better than those for groups B(10.64±1.90;t=-2.92;P=0.004)and C(10.82±2.01;t=-3.29;P=0.001).CONCLUSION Insertion of 8 mm internal diameter Viatorr stent has no significant effects on liver reserve function.Changes of liver reserve function in the medium and long term may be related to the etiology and treatment of portal hypertension.展开更多
OBJECTIVE: To evaluate the effectiveness of the Traditional Chinese Medicine tonifying-kidney and regulating-liver therapy on diminished ovarian reserve(DOR).METHODS: The literature was comprehensively searched up to ...OBJECTIVE: To evaluate the effectiveness of the Traditional Chinese Medicine tonifying-kidney and regulating-liver therapy on diminished ovarian reserve(DOR).METHODS: The literature was comprehensively searched up to August 2019 using four Chinese and three English electronic databases to extract randomized clinical trials(RCTs) comparing Traditional Chinese Medicine tonifying-kidney and regulating-liver prescriptions(combined with hormone therapy or not) with Western Medicine. Data quality evaluation was conducted using the Cochrane risk of bias tool. Meta-analysis was conducted using Revman 5.3 software with effect estimates presented as mean difference(MD), risk ratio(RR), and95% confidence interval(CI).RESULTS: A total of nine RCTs with 512 participants were extracted and eligible for Meta-analysis.There were no significant differences between Chinese medicine and Western Medicine on basal serum follicle-stimulating hormone(FSH) level(MD0.11, 95% CI-0.52 to 0.74, 392 participants, seven trials), anti-Müllerian hormone level(MD 0.48, 95%CI-0.62 to 1.58, 95 participants, two trials), and the FSH and luteinizing hormone ratio(MD 0.01,95% CI-0.95 to 0.96, 115 participants, two trials).Chinese medicine was more effective at improving Traditional Chinese Medicine symptom scores(TCMSS)(MD-2.39, 95% CI-3.83 to-0.94, 160 participants, three trials), effective rate of TCMSS(RR1.18, 95% CI 1.02 to 1.36, 160 participants, three trials), antral follicle count(AFC)(MD 0.55, 95% CI 0.05 to 1.04, 155 participants, three trials), and FSH levels at 3 months post-treatment(MD-4.77, 95% CI-6.09 to-3.45, 137 participants, two trials).CONCLUSION: Compared with Western Medicine,tonifying-kidney and regulating-liver therapy is more effective at relieving symptoms and improving AFC and FSH at 3 months post-treatment.展开更多
BACKGROUND As a country with a high burden of hepatitis B,China has about 86 million cases of hepatitis B virus infection,ranking the first in the world.Currently,there are about 390000 deaths due to hepatitis B-relat...BACKGROUND As a country with a high burden of hepatitis B,China has about 86 million cases of hepatitis B virus infection,ranking the first in the world.Currently,there are about 390000 deaths due to hepatitis B-related complications such as liver cirrhosis and liver cancer every year.Consequently,how to control portal hypertension,improve liver functional reserve,and reduce the incidence of hepatic failure and liver cancer in such patients is the focus of current clinical attention.Previous clinical study in our center suggested that at 24 mo after transjugular intrahepatic portosystemic shunt(TIPS),the liver functional reserve of patients with hepatitis B cirrhosis was better than that of patients with alcoholinduced and immune cirrhosis,which may be related to the effective etiological treatment.AIM To investigate the clinical efficacy of three first-line antiviral drugs recommended by the guidelines of prevention and treatment for chronic hepatitis B in China(2019)in the treatment of patients with hepatitis B-related cirrhosis who had received a TIPS.METHODS The clinical data of 137 patients with hepatitis B-related cirrhosis with portal hypertension after receiving TIPS at our centre between March 2016 and December 2020 were analysed retrospectively.According to different anti-viral drugs,the patients were divided into entecavir(ETV)(n=70),tenofovir alafenamide fumarate(TAF)(n=32),and tenofovir disoproxil fumarate(TDF)(n=35)groups.The cumulative incidence of hepatic encephalopathy and hepatocellular carcinoma,survival,and changes in hepatic reserve function and glomerular filtration rate in patients treated with different antiviral drugs within 24 mo after surgery were investigated.RESULTS At 24 mo after surgery,the Child-Pugh score in the TAF group(6.97±0.86)was lower than that in the TDF(7.49±0.82;t=-2.52,P=0.014)and ETV groups(7.64±1.17;t=-2.92,P=0.004).The model for end-stage liver disease score in the TAF group at 24 mo after surgery was 9.72±1.5,which was lower than that in the TDF(10.74±2.33;t=-2.09,P=0.040)and ETV groups(10.97±2.17;t=-2.93,P=0.004).At 24 mo after surgery,the estimated glomerular filtration rate(eGFR)in the TAF group(104.41±12.54)was higher than that in the TDF(93.54±8.97)and ETV groups(89.96±9.86)(F=21.57,P<0.001).CONCLUSION At 24 mo after surgery,compared with TDF and ETV,TAF has significant advantages in the improvement of liver functional reserve and eGFR.展开更多
基金supported by the National Natural Science Foundation of China(7130108161373137)+1 种基金the Natural Science Foundation of Jiangsu Province(BK20130877BK2012833)
文摘According to low earth orbit（LEO） satellite systems with users of different levels, a dynamic channel reservation scheme based on priorities is proposed. Dynamic calculation of the thresholds for reserved channels is the key of this strategy. In order to obtain the optimal thresholds, the traffic is predicted based on the high-speed deterministic movement property of LEO satellites firstly. Then, a channel allocation model based on Markov is established. Finally, the solution of the model is obtained based on the genetic algorithm. Without user location, this strategy effectively reduces handover failures and improves channel utilization by adjusting dynamically the thresholds according to traffic conditions. The simulation results show that the system＇s overall quality of service can be improved by this strategy.
基金support by the National Natural Science Foundation of China (61401360)the Fundamental Research Funds for the Central Universities (3102017zy026)+1 种基金the Natural Science Basic Research Plan in Shaanxi Province of China (2016JM6017)the Scientific Research Program Funded by Shaanxi Provincial Education Department (16JK1702)
文摘In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multiplexing systems. During the SCR procedure, only the element with the maximal amplitude is picked for processing, which not only decreases the algorithm complexity, but also helps to overcome the BER deterioration. With the LSA method, the amplitude of the peak-cancelling signals can approximate to that of the original clipping noise as much as possible. Through the combination of the optimization factor in the LSA method, the classic SCR method can achieve better PAPR reduction with faster convergence. Simulation results show that the proposed SCR-LSA TR scheme has less in-band distortion and smaller out-of-band spectral radiation. The BER of the proposed scheme shows a better performance especially under the 16-QAM over the additive white Gaussian noise channel.
文摘Call admission control (CAC) and resource reservation (RR) for mobile communication are two important factors that guarantee system efficiency and quality of service (QoS) required for different services in a very scarce resource as the radio spectrum. A new scheme was proposed which extends the concepts of resource sharing and reservations for wideband code division multiple access (WCDMA) systems with a unique feature of soft capacity. Voice and data traffic were considered. The traffic is further classified into handoff and new requests. The reservation thresholds were dynamically adjusted according to the traffic pattern and mobility prediction in order to achieve the maximum channel utilization, while guaranteeing different QoS constraints. The performance of proposed scheme was evaluated using Markov models. New call blocking probability, handoff call dropping probability, and channel utilization were used as benchmarks for the proposed scheme.
基金supported by the National Natural Science Foundation of China(82271671)Nanjing Drum Tower Hospital Academic Innovation Peak Fund(2024-DF-02)+4 种基金Clinical Trials from Nanjing Drum Tower Hospital(2023-LCYJ-MS-05)Nanjing International Science and Technology Cooperation Program(202201027)to L.D.Research Project of State Key Laboratory of Reproductive Medicine and Offspring Health(SKLRM-2022D2)Changzhou Medical Center of Nanjing Medical University(CMCM202203)Clinical Trials from Nanjing Drum Tower Hospital(2022-LCYJ-ZD-02)to H.S.
文摘Ovarian aging is characterized by a progressive decline in oocyte quality and quantity with age.Icariin(ICA),a flavonoid compound derived from Epimedium species,has demonstrated potential as an agent for ovarian restoration.In this study,a subcutaneous implantation system using gelatin methacryloyl(GelMA)hydrogel embedded with ICA was developed to restore ovarian function in aged female mice.Mice were assigned to receive subcutaneous implantation of GelMA alone(GelMA group),GelMA containing ICA(GelMA/ICA group),or a sham operation.Ovarian morphology,serum hormone levels,follicle counts across developmental stages,and reproductive outcomes were evaluated.In vitro fertilization(IVF)and embryo culture assays were performed to assess oocyte developmental potential,while a 10 day natural mating trial was conducted to determine fertility restoration.RNA sequencing(RNA-seq)and RT-qPCR were performed to elucidate the underlying molecular mechanisms.Results showed that GelMA/ICA treatment significantly increased ovarian index(0.19±0.01 vs.0.13±0.01,P<0.0001)and follicle numbers at all developmental stages,including primordial(383.33±151.65 vs.107.14±32.26,P<0.0001),primary(203.33±83.22 vs.91.43±27.04,P=0.003),and secondary follicles(154.17±52.00 vs.59.28±20.50,P=0.029)compared to the sham controls.Hormonal analyses revealed a significant reduction in serum follicle-stimulating hormone(FSH,11.97±3.53 vs.53.10±17.89 ng/mL,P=0.0008),accompanied by elevated anti-Müllerian hormone(AMH,22.97±2.26 vs.5.54±1.56 ng/mL,P<0.0001)and estradiol(E2,315.30±37.62 vs.168.5±14.78 pg/mL,P<0.0001).Oocyte yield and developmental potential improved significantly,as reflected by the increased number of superovulated MII oocytes(17.83±5.15 vs.4.83±4.79,P=0.0002),and higher proportions of two-cell(85.90%±6.16%vs.50.00%±10.00%,P=0.0009),four-cell(81.67%±9.76%vs.50.00%±10.00%,P=0.0061),and blastocyst stage embryos(64.25%±10.55%vs.23.33%±15.28%,P=0.0067).Live birth numbers were significantly increased following GelMA/ICA treatment(6.90±3.21 vs.1.72±2.05,P=0.0001).Transcriptomic analysis revealed up-regulation of genes associated with cytoskeletal organization(Vil1,Tubb3),lipid storage(Soat2,Plin4),oocyte maturation(Oosp2),and cytokine secretion(Cxcl12).Collectively,these findings suggest that GelMA/ICA hydrogels effectively reverse key hallmarks of ovarian aging and restore reproductive function in aged mice,offering a promising platform for fertility preservation and a novel therapeutic for future investigations into ovarian aging.
基金supported by the National Natural Science Foundation of China (32160292, 32471681, and 32201575)Jiangxi “Double Thousand Plan”(jxsq2020101080)+1 种基金the Natural Science Foundation of Jiangxi Province (20224BAB205008, 20224BAB213033, and 20242BAB2538)Jiangxi Province Science and Technology+Water Resources” Joint Plan Project (2023KSG01001 and 2022KSG01010)
文摘Accurately forecasting ecosystem services is critical for enhancing our understanding and improving management practices within nature reserves,particularly in light of climate change,land use/cover changes,and their complex interactions.However,existing studies often fail to fully consider vegetation response,constituting a gap in the comprehensive assessment of changes in ecosystem services.Therefore,a coupled model framework integrating climate change,land use change,and vegetation dynamics was developed to allow for the simulation of dynamic ecosystem service scenarios throughout the twenty-first century.The Jiulianshan National Nature Reserve in Jiangxi Province was considered as the study area.The results showed that ecosystem services and their synergistic effects will be optimized under scenarios that emphasize strict protection of ecological lands and incorporating the SSP1-2.6 scenario.However,sustaining optimized ecosystem services poses significant challenges in scenarios characterized by resource-intensive development and ongoing climate warming,as in the SSP5-8.5 scenario.Notably,discernible variations exist in balancing and synergizing the management of ecosystem services across diverse land uses and forest types.Our study underscores the importance of integrating vegetation response into the framework of ecosystem service forecasting,which is essential for assisting nature reserves in effectively addressing the multifaceted risks associated with climate change and rapid socio-economic development.
基金funded by Science and Technology Project of Hebei Education Department[QN2023085].
文摘Agricultural land development is a pivotal strategy for addressing the global food security crisis.Barren grassland,especially those in mountainous regions,constitutes critical areas where cultivation can substantially enhance land resources.This study highlights the necessity for a precise correlation between land development initiatives and constraints in order to optimize efficiency and enhance the effectiveness of such projects,with the core being the seamless integration of land development engineering and techniques to eliminate agricultural constraints.This study employs a systems engineering approach to classify improvement factors into mobile and fixed categories,elucidating the integration methods of constraint factors.Adhering to the Wooden Barrel Principle,these constraints were rigorously analyzed based on soil quality,land topography,water availability,and agricultural infrastructure.An innovative method of engineering type combination is proposed,which effectively explains the correlation between natural factors combination,project type combination,and target factors combination.It provides a convenient way for the selection of barren grassland development projects and lays a foundation for land planning,development project establishment,program selection,engineering design,and budget preparation.Taking Tang County of China as an example,it is divided into 19 factor improvement areas,a quick reference table of engineering types is established,and 14 main types of engineering combinations are obtained,which lays a foundation for the application of theoretical framework in practice.
文摘Objective: To compare the functional outcomes of patients who had parotid masseter fascia reserved and unreserved flap elevating scheme in parotidectomy, especially the morbidity of Frey's syndrome. Methods: Twenty-three patients (group A) had parotid masseter fascia reserved in the parotidectomy, 32 patients (group B) had parotid masseter fascia unreserved in the operation. Compare the morbidity of gustatory sweating syndrome of the two groups. Results: Follow-up after 6 months to 2.5 years, gustatory sweating syndrome occurred in 4 patients of group A (17%), 17 patients in group B (57%). Conclusion: Reservation technic of the parotid masseter fascial in parotidectomy could prevent regeneration of parasympathetic nerve and thus prevent Frey's syndrome post-operation.
文摘This paper had described the influence of restoration and reservation of Xi'an Qujiang Pond Ruins Park on urban landscape with an emphasis,proposed to promote urban landscape development by making use of cultural ruins. It analyzed the good and bad effects of Xi'an Qujiang Pond Ruins Park on urban landscape and concluded that cultural ruins should be used to shape new outlook of urban landscape,so as to discuss the momentous significance of cultural ruins in urban landscape.
基金Supported by National Natural Science Fund (41075008)Chinese Meteorological Climate Changes Program (280200S011000)Gansu Meteorological Bureau Climate Science and Research Program(2011-09)~~
文摘[Objective] The aim was to explore the spatial and temporal distribution characteristics of wind energy resource and preservation in central and west area of Hexi Corridor. [Method] By dint of the wind speed data from 1955 to 2007 in ten meteorological observation station in central and west area of Hexi Corridor,and special wind tower fine data from January to December in 2007,the distribution and reserves of the region＇s wind energy resources were studied. [Result] The results showed that environmental wind speed was relatively stable in central and west Hexi Corridor. There were no distinct changes in climate characteristics distribution. There were regional differences in the distribution of wind energy,and there was a large numerical area of wind energy in Gazhou County and Yumen City; Wind energy in the region generally was higher. The wind energy density was above 100 w/m2 in the 10 m layer,around 140 w/m2 in most places,and was more than 200 w/m2 in the large number area. The wind grew in vertical direction along with the linear growth of height. Each 10 m high wind increased to 15 w/m2 averagely,50m layer wind energy was greater than the general 240 w/m2 and there were obvious changes on daily and annual with wind energy in central and west area of Hexi Corridor. The duration from March to May was a wind energy-intensive stage,10m height from the ground in the wind around 10：00 in low-value. After growing from 11：00,it met the day largest number at 18：00,and then reduced gradually. Effective wind speed hours in the region in general were more than 6 200 h,and the value in the large areas was close to 7 600 h. [Conclusion] The study laid basis for the development and application of wind energy in central and west area of Hexi Corridor.
文摘[Objective] The aim was to explore the effects of cultivation and seed reservation methods on quality and disease/insect damages of maca seed in cold highland areas,providing scientific references for cultivation and seed reservation and planning of maca vareity.[Method] Yellow,purple and black maca were selected and cultivated in the region with an elevation of 3 000 m to be experimental materials and cultivation and seed reservation methods were as follows：maca seed reservation in situ,seed reservation in original soils maca grown after selection of maca balls,and seed reservation in the region with an elevation of 2 700 m after selection of maca ball,seed reservation in greenhouses in the region with an elevation of 2 400 m after selection of maca ball,and growing selected balls in greenhouses and transplanting to the farmlands with an elevation of 2 400 m.[Result] The cultivation and seed reservation methods had significant or extremely significant effects on maca phenological phase;maca in different colors were treated by different cultivation and seed reservation methods,showing insignificant effects on disease and insect damages.[Conclusion] It can be concluded that the selected maca balls stored for 15 d as per the method grown in the region with an elevation of 2 700 m will improve seed quality and reduce disease or insect damages.
基金Supported by State Forestry Administration"Public Welfare Program"(201204205)~~
文摘[Objective] The aim is to conduct systematic diagnoses on the eco-vulnerability in Daqinggou National Natural Reserve. [Method] A kind of ＂problem pile＂ is proposed about 58 interrelated problems of ecological vulnerability by field survey and questionnaires and a ladder diagram of interrelations among the problems is established. The root problems, basic problems, core problems, interrelation and solving approaches are proposed, as well. [Result] It can be concluded from system diagnosis that fragile ecosystem of the Reserve can be observed from poor disasterresistibility, lower species diffusivity, lower system metabolism and poor system restorability. According to system diagnoses, management planning and control subsystem is key for protection of system vulnerability and solving different problems in process-oriented system. Conservation of the Reserve and ecological education on tourists are indispensible. It can be concluded from diagnoses that plant updating, evolution and ill growth in the Reserve are the focus of the vulnerable ecosystem, which influence species diffusivity, system metabolism and restorability and constitute central nodes of process-oriented and effect-oriented subsystems. [Conclusion] The research provides references for solving vulnerability issues of conservation and tourism management in Daqinggou National Nature Reserve.
文摘The concept of the brain cognitive reserve is derived from the well-acknowledged notion that the degree of brain damage does not always match the severity of clinical symptoms and neurological/cognitive outcomes.It has been suggested that the size of the brain(brain reserve) and the extent of neural connections acquired through life(neural reserve) set a threshold beyond which noticeable impairments occur.In contrast,cognitive reserve refers to the brain's ability to adapt and reo rganize stru cturally and functionally to resist damage and maintain function,including neural reserve and brain maintenance,resilience,and compensation(Verkhratsky and Zorec,2024).
文摘Elk are seen at the Tian’ezhou National Nature Reserve for Elk in Shishou,Hubei Province,on 27 November 2025.The reserve’s elk population has risen from just 64 in the 1990s to more than 4,500 today.
文摘CHINA.Dinghu Mountain National Nature Reserve.Located in Zhaoqing,Guangdong Province,Dinghu Mountain National Nature Reserve is a pristine natural sanctuary spanning 1,133 hectares within the low mountain ranges of the Dayunwu Mountains.
基金supported by the National Major Scientific and Technological Project of China (No.2010BAK69B13,2010BAK69B14)the Major Project of the Shanghai Scientific and Technological Committee(No. 10dz1200903,10dz1200700)
文摘Two representative zones in Chongming Dongtan which faced the Yangtze River and East China Sea respectively were selected to study the variability of soil organic carbon （SOC） reservation capability between coastal wetland and riverside wetland in the Chongming Dongtan wetland as well as its mechanism by analyzing soil characteristics and plant biomass.The results showed the SOC content of riverside wetland was only 48.61% （P=0.000 〈 0.05） that of coastal wetland.As the organic matter inputs from plant litter of the coastal wetland and riverside wetland were approximately the same,the higher soil microbial respiration （SMR） of riverside wetland led to its lower SOC reservation capability.In the riverside wetland,the high soil microbial biomass,higher proportion of β-Proteobacteria,which have strong carbon metabolism activity and the existence of some specific aerobic heterotrophic bacteria such as Bacilli and uncultured Lactococcus,were the important reasons for the higher SMR compared to the coastal wetland.There were additional differences in soil physical and chemical characteristics between the coastal wetland and riverside wetlands.Path analysis of predominant bacteria and microbial biomass showed that soil salinity influenced β-Proteobacteria and microbial biomass most negatively among these physical and chemical factors.Therefore the low salinity of the riverside area was suitable for the growth of microorganisms,especially β-Proteobacteria and some specific bacteria,which led to the high SMR and low SOC reservation capability when compared to the coastal area.
文摘BACKGROUND:Whether a major liver resection is safe has been judged mainly from the patient’s hepatic reserve.However,a safe limit for liver resection does not exist yet.This study aimed to construct a new scoring system as a guide to determine a safe limit for liver resection and avoid liver dysfunction after hepatectomy.METHODS:Eighty-six patients with hepatocellular carcinoma who had undergone hepatectomy in West China Hospital from March 2007 to June 2010 were reviewed.The patients were classified according to the levels of total bilirubin after hepatectomy and the parameters in the perioperative period were compared.Receiver operating characteristic (ROC) analysis was made to assess the liver function compensatory (LFC) value to predict liver dysfunction of the patients after hepatectomy.LFC value is defined as the preoperative KICG value×22.487+standard remnant liver volume (SRLV)×0.020.RESULTS:Patients were classified into group Ⅰ (normal group,n=69) and group Ⅱ (with total bilirubin >85.5 μmol/L for 7 days after hepatectomy,n=17) based on the levels of total bilirubin after hepatectomy.Group II was further divided into two subgroups:recovered subgroup (n=14) and fatal subgroup (n=3).There were no significant differences in preoperative data or intraoperative findings except the indocyanine green test parameters (KICG and ICG R15) and SRLV.ROC analysis showed that the sensitivity and specificity of an LFC value ≤13.01 were 94.1% and 82.6% respectively for predicting liver dysfunction of the patients after hepatectomy.CONCLUSIONS:The LFC value appears to be a good predictor of postoperative liver dysfunction in patients who undergo hepatectomy for HCC.An expected LFC value of 13.01 seems to be a safe limit for liver resection.
文摘BACKGROUND As transjugular intrahepatic portosystemic shunt(TIPS)creation alters the hemodynamic status of the portal system,whether reduced portal blood supply affects the synthetic reserve function of the liver has been the focus of clinical attention.Since the Viatorr stent entered the Chinese market in 2015,it has not yet been widely used in clinical practice.Further,unlike other countries,the main cause of liver cirrhosis in China is viral hepatitis.Therefore,use of the Viatorr stent to establish a TIPS channel in patients with liver cirrhosis with differing etiologies is of great clinical interest.AIM To investigate factors affecting changes in liver reserve function after TIPS Viatorr stent implantation.METHODS Clinical data from 200 patients with cirrhotic portal hypertension who received TIPS treatment from March 2016 to March 2020 were analyzed retrospectively.The patients were divided into three groups(A-C),according to their disease etiology,with post-hepatitis,autoimmune,and alcoholic cirrhosis,respectively.Preoperative and postoperative liver and renal function and coagulation data,Child-Pugh grade,and model for end-stage liver disease(MELD)scores were collected.Statistical analyses were performed using the t-test or chi-square test.The incidence and of hepatic encephalopathy and patient survival were calculated using Kaplan-Meier method.RESULTS The surgical success rate was 100%,with mean portal pressure gradient(mmHg)decreasing from 25.5±5.22 to 10.04±2.76(t=45.80;P<0.001).After 24 mo,the cumulative incidence of hepatic encephalopathy in group A was significantly lower than that in group B/C,while the cumulative survival rate was significantly higher in group A than in group B/C(P<0.05 for both).The Child-Pugh score for group A was 6.96±1.21,which was significantly better than those of groups B(7.42±0.99;t=-2.44;P=0.016)and C(7.52±1.12;t=-2.67;P=0.009).Further,the MELD score for group A(9.62±2.19)was significantly better than those for groups B(10.64±1.90;t=-2.92;P=0.004)and C(10.82±2.01;t=-3.29;P=0.001).CONCLUSION Insertion of 8 mm internal diameter Viatorr stent has no significant effects on liver reserve function.Changes of liver reserve function in the medium and long term may be related to the etiology and treatment of portal hypertension.
基金Supported by the Fundamental Research Funds for the Central Universities Study on the Mechanism of Tonifying-Kidney and Smoothing-Liver on Rats With Diminished Ovarian Reserve Based on PI3K-AKT-mTOR Signaling Pathway(No.2019-JYB-XS-148)National Natural Science Foundation of China Study on the Mechanism of Regulating Endometrial Receptivity by Erbu Zhuyu Decoction Based on NK/M-CSF/NO Signaling Pathway(No.81473721)。
文摘OBJECTIVE: To evaluate the effectiveness of the Traditional Chinese Medicine tonifying-kidney and regulating-liver therapy on diminished ovarian reserve(DOR).METHODS: The literature was comprehensively searched up to August 2019 using four Chinese and three English electronic databases to extract randomized clinical trials(RCTs) comparing Traditional Chinese Medicine tonifying-kidney and regulating-liver prescriptions(combined with hormone therapy or not) with Western Medicine. Data quality evaluation was conducted using the Cochrane risk of bias tool. Meta-analysis was conducted using Revman 5.3 software with effect estimates presented as mean difference(MD), risk ratio(RR), and95% confidence interval(CI).RESULTS: A total of nine RCTs with 512 participants were extracted and eligible for Meta-analysis.There were no significant differences between Chinese medicine and Western Medicine on basal serum follicle-stimulating hormone(FSH) level(MD0.11, 95% CI-0.52 to 0.74, 392 participants, seven trials), anti-Müllerian hormone level(MD 0.48, 95%CI-0.62 to 1.58, 95 participants, two trials), and the FSH and luteinizing hormone ratio(MD 0.01,95% CI-0.95 to 0.96, 115 participants, two trials).Chinese medicine was more effective at improving Traditional Chinese Medicine symptom scores(TCMSS)(MD-2.39, 95% CI-3.83 to-0.94, 160 participants, three trials), effective rate of TCMSS(RR1.18, 95% CI 1.02 to 1.36, 160 participants, three trials), antral follicle count(AFC)(MD 0.55, 95% CI 0.05 to 1.04, 155 participants, three trials), and FSH levels at 3 months post-treatment(MD-4.77, 95% CI-6.09 to-3.45, 137 participants, two trials).CONCLUSION: Compared with Western Medicine,tonifying-kidney and regulating-liver therapy is more effective at relieving symptoms and improving AFC and FSH at 3 months post-treatment.
文摘BACKGROUND As a country with a high burden of hepatitis B,China has about 86 million cases of hepatitis B virus infection,ranking the first in the world.Currently,there are about 390000 deaths due to hepatitis B-related complications such as liver cirrhosis and liver cancer every year.Consequently,how to control portal hypertension,improve liver functional reserve,and reduce the incidence of hepatic failure and liver cancer in such patients is the focus of current clinical attention.Previous clinical study in our center suggested that at 24 mo after transjugular intrahepatic portosystemic shunt(TIPS),the liver functional reserve of patients with hepatitis B cirrhosis was better than that of patients with alcoholinduced and immune cirrhosis,which may be related to the effective etiological treatment.AIM To investigate the clinical efficacy of three first-line antiviral drugs recommended by the guidelines of prevention and treatment for chronic hepatitis B in China(2019)in the treatment of patients with hepatitis B-related cirrhosis who had received a TIPS.METHODS The clinical data of 137 patients with hepatitis B-related cirrhosis with portal hypertension after receiving TIPS at our centre between March 2016 and December 2020 were analysed retrospectively.According to different anti-viral drugs,the patients were divided into entecavir(ETV)(n=70),tenofovir alafenamide fumarate(TAF)(n=32),and tenofovir disoproxil fumarate(TDF)(n=35)groups.The cumulative incidence of hepatic encephalopathy and hepatocellular carcinoma,survival,and changes in hepatic reserve function and glomerular filtration rate in patients treated with different antiviral drugs within 24 mo after surgery were investigated.RESULTS At 24 mo after surgery,the Child-Pugh score in the TAF group(6.97±0.86)was lower than that in the TDF(7.49±0.82;t=-2.52,P=0.014)and ETV groups(7.64±1.17;t=-2.92,P=0.004).The model for end-stage liver disease score in the TAF group at 24 mo after surgery was 9.72±1.5,which was lower than that in the TDF(10.74±2.33;t=-2.09,P=0.040)and ETV groups(10.97±2.17;t=-2.93,P=0.004).At 24 mo after surgery,the estimated glomerular filtration rate(eGFR)in the TAF group(104.41±12.54)was higher than that in the TDF(93.54±8.97)and ETV groups(89.96±9.86)(F=21.57,P<0.001).CONCLUSION At 24 mo after surgery,compared with TDF and ETV,TAF has significant advantages in the improvement of liver functional reserve and eGFR.
