The publisher regrets that the article type for this publication was incorrectly labeled as a Research Article.The correct designation should be Review Article.This correction does not affect the content or conclusion...The publisher regrets that the article type for this publication was incorrectly labeled as a Research Article.The correct designation should be Review Article.This correction does not affect the content or conclusions of the article.The publisher apologizes for any inconvenience caused.展开更多
BACKGROUND Early diagnosis of left ventricular diastolic dysfunction(LVDD)is essential for preventing heart failure.B-type natriuretic peptide(BNP)is a viable marker for predicting LVDD,as elevated BNP levels have bee...BACKGROUND Early diagnosis of left ventricular diastolic dysfunction(LVDD)is essential for preventing heart failure.B-type natriuretic peptide(BNP)is a viable marker for predicting LVDD,as elevated BNP levels have been associated with worsening LVDD in patients with diabetes over time.However,the utility of BNP as a diagnostic marker in diabetes is controversial,as BNP levels are often low in overweight individuals.AIM To examine the effectiveness of BNP levels and fragmented QRS(fQRS)on electrocardiography for diagnosing LVDD in patients with type 2 diabetes.METHODS This retrospective cohort study included 303 patients with type 2 diabetes(67.4±12.3 years old)with preserved ejection fraction(EF)≥50%admitted to Toyama University Hospital for glycemic management and comorbidity evaluation between November 2017 and April 2021.All participants underwent plasma BNP measurement,electrocardiography,and echocardiography.Cardiologists who were blinded to the BNP results assessed the electrocardiograms and echocardiograms.Subgroup analyses were conducted for overweight individuals.RESULTS Receiver operating characteristic(ROC)curve analysis determined optimal BNP cut-off values of 34.8 pg/mL and 7.2 pg/mL for diagnosing LVDD in non-overweight[area under the ROC curve(AUC):0.70]and overweight(AUC:0.55)groups,respectively(P=0.040).In the overweight subgroup,fQRS showed greater diagnostic accuracy for LVDD(AUC:0.67),indicating moderate diagnostic utility compared with the low performance of the BNP cutoff of 35 pg/mL(AUC:0.52)(P=0.010).Multivariate analyses confirmed that fQRS was superior to BNP for LVDD diagnosis regardless of the patient’s weight.CONCLUSION A BNP level≥35 pg/mL in non-overweight individuals may be a reliable LVDD marker.Additionally,fQRS was more effective than BNP in diagnosing LVDD irrespective of the patient’s weight.fQRS can complement BNP in the early detection of LVDD,especially in overweight patients,potentially improving early detection and mitigating progression to heart failure with preserved EF in patients with type 2 diabetes.展开更多
BACKGROUND The microcystic,elongated,and fragmented(MELF)pattern of invasion in endometrioid endometrial carcinoma(EEC)is a special mode of myometrial invasion that has been recently recognized by the pathology commun...BACKGROUND The microcystic,elongated,and fragmented(MELF)pattern of invasion in endometrioid endometrial carcinoma(EEC)is a special mode of myometrial invasion that has been recently recognized by the pathology community.Overex-pression of CXC chemokine receptor 4(CXCR4)in tumor cells contributes to tumor growth,invasion,angiogenesis,metastasis,and recurrence.AIM To explore the correlation between CXCR4 expression in EEC and MELF invasion and clinicopathological features.METHODS A total of 205 EEC patients treated at Peking University People’s Hospital from June 2020 to December 2021 were selected(60 cases with MELF invasion,145 cases without).The clinicopathological features of the two groups were compared,and expression of CXCR4 protein,estrogen receptor,and progesterone receptor was detected and compared by immunohistochemistry.RESULTS EEC with MELF invasion was significantly associated with low tumor grade,lymphovascular space invasion,deep myometrial invasion,cervical stromal involvement,and lymph node metastasis.There was a difference in CXCR4 expression between the two groups,with the MELF group having a significantly higher expression than the non-MELF group.CONCLUSION CXCR4 expression is significantly increased in EEC with MELF invasion and in the MELF invasion area,which may promote tumor invasion and metastasis and has some value for prognostic assessment.展开更多
We investigate distinct non-Hermitian skin effects(NHSEs)in real and Fock spaces induced by the interplay between the Hilbert space fragmentation and multiple non-Hermitian pumping channels.Using an extended Hatano–N...We investigate distinct non-Hermitian skin effects(NHSEs)in real and Fock spaces induced by the interplay between the Hilbert space fragmentation and multiple non-Hermitian pumping channels.Using an extended Hatano–Nelson model with next-nearest neighbor hopping and strong interaction as an example,we found that two fermions loaded in the lattice exhibit different real-space NHSE depending on the Hilbert space fragments to which they belong.Moreover,in the high-energy sector resulting from fragmentation,the two-particle-bound states form a one-dimensional lattice in Fock space,producing a Fock-space NHSE.At half-filling,richer patterns of Fock-space skin-like localization emerge for the different fragmented energy sectors and subsectors while realspace NHSE is suppressed by many-body effects.This study extends our understanding of the interplay between NHSE and Hilbert space fragmentation and provides detailed insights into their manifestation in interacting non-Hermitian systems.展开更多
An in-depth understanding of the fracture behavior and mechanism of metallic shells under internal explosive loading can help develop material designs for warheads and regulate the quantity and mass distribution of th...An in-depth understanding of the fracture behavior and mechanism of metallic shells under internal explosive loading can help develop material designs for warheads and regulate the quantity and mass distribution of the fragments formed.This study investigated the fragmentation performance of a new high-carbon silicon-manganese(HCSiMn)steel cylindrical shell through fragment recovery experiments.Compared with the conventional 45Cr steel shell,the number of small mass fragments produced by the HCSi Mn steel shell was significantly increased with a scale parameter of 0.57 g fitted by the Weibull distribution model.The fragmentation process of the HCSi Mn shell exhibited more brittle tensile fracture characteristics,with the microcrack damage zone on the outer surface being the direct cause of its high fragmentation.On the one hand,the doping of alloy elements resulted in grain refinement by forming metallographic structure of tempered sorbite,so that microscopic intergranular fracture reduces the characteristic mass of the fragments;on the other hand,the distribution of alloy carbides can exert a"pinning"effect on the substrate grains,causing more initial cracks to form and propagate along the brittle carbides,further improving the shell fragmentation.Although the killing power radius for light armored vehicles was slightly reduced by about 6%,the dense killing radius of HCSiMn steel projectile against personnel can be significantly increased by about 26%based on theoretical assessment.These results provided an experimental basis for high fragmentation warhead design,and to some extent,revealed the correlation mechanism between metallographic structure and shell fragmentation.展开更多
This study is aimed to investigate the clinical significance and the short-term prognostic value of frag- mented QRS （fQRS） for patients with acute myocardial infarction （AMI）. Three hundred patients with AMI were...This study is aimed to investigate the clinical significance and the short-term prognostic value of frag- mented QRS （fQRS） for patients with acute myocardial infarction （AMI）. Three hundred patients with AMI were tested with retrospective analysis on the patients＇ clinical information, hospitalized treatment, fQRS onset time, location of lesions, and other relevant data, in order to assess the relationship between the presence of fQRS and its prognosis. The rates of malignant cardiac arrhythmia, left ventricular systolic dysfunction （LVSD）, and mortality in the positive fQRS group were 13.6%, 29.2%, and 23.7%, respectively, with all showing a p value 〈0.05. For the ST segment elevation myocardial infarction （STEMI） subgroup, all the rates showed significant differences with a p value 〈0.01, while for the non-STEMI （NSTEMI） subgroup showed no significant differences. In patients with a positive fQRS, there were no differences in malignant cardiac arrhythmia between patients with and without percutaneous coronary in- tervention （PCI） （p〉0.05）. As for the LVSD and mortality, the p values between patients with and without PCI were 0.031 and 0.000, respectively, suggesting statistical significance. The results imply that AMI patients with positive fQRS especially for the patients with STEMI had higher rates of malignant cardiac arrhythmia, LVSD, and mortality than the non-fQRS group. Patients of AMI with positive fQRS, who underwent early revascularization, could lower the incidence of the cardiovascular event. In addition, the presence of fQRS could be used as an indication of early in- tervention treatment for patients.展开更多
Objective To describe the clinical characteristics of idiopathic ventricular fibrillation （IVF） with fragmented QRS complex （f-QRS） and J wave in resting electrocardiogram. Methods We reviewed data from 21 case su...Objective To describe the clinical characteristics of idiopathic ventricular fibrillation （IVF） with fragmented QRS complex （f-QRS） and J wave in resting electrocardiogram. Methods We reviewed data from 21 case subjects in our hospital who were resuscitated after cardiac arrest due to IVF and assessed the prevalence of f-QRS and J wave in resting electrocardiogram （ECG）. All the case subjects were classified among three groups based on the electrocardiographic morphology： group I, both f-QRS and J wave were observed （n = 6）, group II, only J wave was observed （n = 9）, group III, neither f-QRS nor J wave was observed （n = 6）. Population characteristics, history of syncope or sudden cardiac arrest, incidence of ventricular fibrillation （VF）, and circumstance of VF were evaluated among the three groups. Results The incidence of index events （syncope, survived cardiac arrest and VF episodes recorded in implantable cardioverter defibrillator （ICD） or pacemakers） was 13.4 ~ 5.6 per-year in group I, 10.8 ~ 3.9 per-year in group II, and 9.8 -4- 4.2 per-year in group HI. There were significant differences in incidences among the three groups, the most frequent index events were observed in group I. The hazard ratio for incidence was 3.2 （95%CI, 1.1-7.9; P = 0.01）. The history and circumstance of the index events were different among the groups. In group I, all the index events occurred during sleep in early morning. In group II, four subjects suffered VF during strenuous physical activities or agitation state, two during sleep in early morning, three in usual activity. In group III, one subject suffered VF during sleep in early morning, one in agitation state, four in usual activity. Conclusions This study suggests that the IVF patients with the combined appearance of f-QRS and J wave in the resting ECG suffer an increased risk of VF, this subgroup of IVF patients has a unique clinical feature.展开更多
The road effect on small rodent population is investigated at 8 fragmented forest areas in the Baekdudaegan mountain range, South Korea in September 2001. We especially focused on the distribution and body condition o...The road effect on small rodent population is investigated at 8 fragmented forest areas in the Baekdudaegan mountain range, South Korea in September 2001. We especially focused on the distribution and body condition of small rodents near the roads. Korean field mouse (Apodemus peninsulae) seems to be more sensitive to the existence of a road than striped field mouse (Apodemus agrarius). Korean field mouse prefers interior forest area to around road. Striped field mouse is a habitat generalist and has wide distributional range around road, but Korean field mouse is forest-inhabiting species and their distribution is limited in forest area. These results suggest the effect of road is different on each small rodent species and their habitat preferences.展开更多
The development of information technology has changed people's learning methods. Fragmented learning,as an informal learning method,has become an important way to accept new knowledge and learn new technologies. T...The development of information technology has changed people's learning methods. Fragmented learning,as an informal learning method,has become an important way to accept new knowledge and learn new technologies. Through analyzing the connotation,characteristics,and advantages and disadvantages of fragmented learning,this paper came up with reasonable recommendations for fragmented learning. To truly become systematic and holistic knowledge,fragmented knowledge must be explored,understood,integrated and internalized. This paper is expected to play an important guiding role in building a lifelong learning society.展开更多
Background:Remnant microhabitats are important for bird habitat selection and plant regeneration in the fragmented habitat.However,empirical information on the consequences of how microhabitat use by birds affects the...Background:Remnant microhabitats are important for bird habitat selection and plant regeneration in the fragmented habitat.However,empirical information on the consequences of how microhabitat use by birds affects the early recruitment of plants is lacking.Methods:In this study,we evaluated whether microhabitat selection by the Black Bulbul(Hypsipetes leucocephalus)(J.F.Gmelin,1789)impacts the early recruitment of the endangered tree species,the Chinese Yew(Taxus chinensis(Pilger)Rehd),in a fragmented forest over a 4-year period(2011–2012,2018–2019).Results:Our results showed the main factors affecting H.leucocephalus microhabitat selection were distance to the nearest T.chinensis mature tree,herb cover and density,leaf litter cover,and vegetation type.Moreover,the results of logistic regression also highlighted the importance of elevation,distance to light gap and roads,tree cover in bird microhabitat selection.Furthermore,the seed emergence rate in microhabitats used by birds did not differ from the natural forest,which was related to five factors of bird microhabitat.The Random Forest model showed that seedling emergence rate was increased with leaf litter cover and distance to fallen dead trees,but decreased in relation to herb cover,slope,and elevation.Conclusion:Our results highlight the importance of remnant microhabitats in fragmented forests for sustaining forest ecology and optimal management.The contribution of microhabitats used by birds to plant recruitment provides insights into how frugivore species contribute to plant regeneration,which should be incorporated in future conservation and management practices of fragmented forests.展开更多
Background: Patients requiring valve replacement at a younger age, for rheumatic heart disease was apparently increasing after the new age practice of contraception. Methods: In 2012, data of patients referred to tert...Background: Patients requiring valve replacement at a younger age, for rheumatic heart disease was apparently increasing after the new age practice of contraception. Methods: In 2012, data of patients referred to tertiary care hospital from two cardiology screening camps conducted in the community, were analyzed for the severity of presentation of rheumatic heart disease and associated contraception status by dividing into the three age groups—20 - 35 years, 36 - 50 years, >51 years;~400 patients attended the camps;31 female and 2 male patients were referred to the tertiary care hospital for further evaluation and categorized treatment, including valve replacement surgeries;among the 33 referred patients, belonging to the three age groups, the data were analyzed for [if any] correlation of contraception status with severe rheumatic heart disease. 8 randomly chosen males, of the 3 age groups, from a different community, whose life partners had undergone sterilization, were assessed for their serum testosterone levels. Results: Among 20 - 35 years, 7 female patients with contraception required valve replacement surgeries [p 51 years, 3 female and 2 male patients without contraception received medical treatment only展开更多
In the era of new media,people’s lifestyle,education and the like are inseparable from the Internet.At the same time,due to the emergence of smart devices such as mobile phones and tablet computers,people’s reading ...In the era of new media,people’s lifestyle,education and the like are inseparable from the Internet.At the same time,due to the emergence of smart devices such as mobile phones and tablet computers,people’s reading habits have changed.Fragmented reading has become an important form of reading for college students.College students themselves have the strong ability to accept change,so fragmented reading has gradually become an important form of student learning.This paper mainly analyses fragmented reading by college students and its impact on society in the era of new media.展开更多
This paper attempts to investigate the feasibility and learning effects of English fragmented learning via mobile devices.Questionnaires and interviews were employed to do the survey on 157 undergraduates from 24 univ...This paper attempts to investigate the feasibility and learning effects of English fragmented learning via mobile devices.Questionnaires and interviews were employed to do the survey on 157 undergraduates from 24 universities in China.The research findings reveal that English fragmented learning via mobile devices has some positive effects on the improvement of learners’knowledge and learning ability.In addition,there have been a certain number of useful learning resources and platforms with diversified features.The study has the implications that fragmented mobile learning is feasible and can be popularized in English learning.展开更多
Background Based on previous studies, a fragmented QRS （fQRS） complex, as a predictive biomarker of myocardial scarring condition, could be used to predict the outcomes of cardiac resynchronized therapy （CRT）. How...Background Based on previous studies, a fragmented QRS （fQRS） complex, as a predictive biomarker of myocardial scarring condition, could be used to predict the outcomes of cardiac resynchronized therapy （CRT）. However, this conclusion is still debatable. Methods Fifty ischemic or non-ischemic cardiomyopathy patients failure （aged 65 ± 10 yrs, 34 males, 16 females） with refractory heart, diagnosed by the criteria of New York Heart Association received CRT. The ECGs of 18 patients with a fQRS complex （divided by Das） were compared with those of 32 patients without a fQRS complex, who were evaluated by 12-lead ECG before CRT. The patients were followed up for six months, and 12-lead ECG and echocardiography were reviewed. At least 15% reduction in the left ventricular end-systolic volume （LVESV） was defined as responders according to the data obtained for between-group and intra-group analysis. Results Six patients （33.3%） in the fQRS group and 24 patients （75%） in the non-fQRS group responded well. In addition, comparisons of indicators from surface ECG and echocardiography 6 months after CRT showed that the non-fQRS group benefited from CRT significantly more than the fQRS group. Conclusions The fQRS complex has good predictive value for responsiveness to CRT. Non-fQRS complex patients with refractory heart failure may benefit more from CRT, and these patients need to receive this treatment as early as possible.展开更多
The Chinese Grouse (Tetrastes sewerzowi) is a rare, endemic bird in China, inhabiting conifer-dominated mountain forests. Both the natural fragmentation and heavy cutting of mature forests have resulted in patchy grou...The Chinese Grouse (Tetrastes sewerzowi) is a rare, endemic bird in China, inhabiting conifer-dominated mountain forests. Both the natural fragmentation and heavy cutting of mature forests have resulted in patchy grouse habitats. We used SPOT (XS-sensor) satellite imagery to discriminate between open land and conifer or broadleaf forests. The area analyzed is about 120000 ha in size and includes the Lianhuashan Nature Reserve and the Yeliguan Forestry Park. We identiifed 4111 ha of mature coniferous forests in 229 patches (maximum 332 ha, mean 18 ha) as the habitat used by Chinese Grouse throughout the year. We examined 31 forest islands of different sizes and degrees of isolation for the presence of Chinese Grouse. We used generalized linear models (GLM) with binomial error structure and logit link function to estimate the probability of Chinese Grouse occupancy in a forest fragment. Habitat patch size (hs) and distance to the next occupied fragment (doc) were used as predictor variables, important for occupancy. Small habitat islands were disproportionately less likely to be occupied than large, nearby habitats. There was a clear speciifc habitat size of about 40 ha, above which habitat fragments were occupied more often. Suitable habitat fragments isolated by more than 2 km appeared to be inaccessible to Chinese Grouse. The results have been used in reforestation projects to establish linking corridors in the study area.展开更多
OCTOBER 25 is Central African Regional Integration Day. Few people know or observe this holiday because the citizens of Africa＇s poorest and most conflict-prone region have little to celebrate.
A number of isolated islands of Leymus chinensis ＋ herbosa community were investigated in fragmented habitat islands, by Braun-Blanquet field survey approach, in a degenerated meadow in the Songnen Plain, China in 20...A number of isolated islands of Leymus chinensis ＋ herbosa community were investigated in fragmented habitat islands, by Braun-Blanquet field survey approach, in a degenerated meadow in the Songnen Plain, China in 2007. These islands were classified as large, medium, and small scales on the basis of the island area （100-1000m2, large island; 50-100m2, middle island; 10-50m2, small island）. Each scale of the investigation involved eight islands. The responses ofβ-diversity patterns of plant taxon to the habitat fragmentation at local community and metacommunity levels were analyzed on different scales of 24 isolated islands. The results indicated that at the local community level, there were 57 species belonging to 20 families and 49 genera in large islands, 49 species belonging to 16 families and 40 genera in middle islands, and 27 species belonging to eight families and 23 genera in small islands, β-diversity indexes for species, genus and family in large, middle, and small islands varied greatly, and the highest value of the indexes was not noted in the largest island. However, the average of the data obtained at the three scales showed that across large islands, Whittaker indexes were low and Bray-Curtis similarity indexes were high, while across small islands, Whittaker indexes were high and Bray-Curtis similarity indexes were low. At the metacommunity level, Whittaker indexes for species and genus showed a great significantly negative double logarithmic correlation （p〈0.01） with the island area, whereas the Bray-Curtis indexes for species, genus and family showed a great significantly positive double logarithmic correlation （p〈0.01） with the island area. At both local community and metacommunity levels, tumovers of species and genus could respond more sensitively to spatial changes of plant diversity patterns than that of family. Hence, the species and the genus could be used for the analysis offl-diversity patterns of plant community.展开更多
The population structure and regeneration status of Magnolia punduana Hk. f. & Th., an endemic tree species of northeast India were investigated in fragmented forests in the Jarain Hills and in adjoining areas of ...The population structure and regeneration status of Magnolia punduana Hk. f. & Th., an endemic tree species of northeast India were investigated in fragmented forests in the Jarain Hills and in adjoining areas of Meghalaya state. The population structure was discontinuous in all the fragments with the absence of individuals in higher diameter classes. The number of individuals increased with the size of the fragment patches(p < 0.004). The density of mature trees(≥5 cm dbh) was high(24–30 individuals ha-1) in the largest fragment(>105 ha). The number of seedlings and saplings were also higher in the larger fragments. Human-related disturbances had a negative impact on the species population(p<0.002). Variation in the population density in different forest patches has been attributed to fragment size, site characteristics and ongoing human disturbances. The restricted distribution of the species coupled withexploitation and habitat destruction underlines the need for its conservation.展开更多
In this study we document the prevalence of gastrointestinal parasites （helminths and protozoans） found in fecal samples of populations of Alouatta palliata mexicana and ofA. pigra in Los Tuxtlas and in Palenque, so...In this study we document the prevalence of gastrointestinal parasites （helminths and protozoans） found in fecal samples of populations of Alouatta palliata mexicana and ofA. pigra in Los Tuxtlas and in Palenque, southeast Mexico, and its re- lation to habitat condition, sex/age and season. Nineteen parasite morphotypes were detected in the fecal samples from populations of the two howler monkeys, of which 58% were shared by both species. When considering all parasite species, populations of the two howler species were more likely to be parasitized in fragmented habitat compared to continuous habitat. Individuals of both howler monkey species that lived in fragmented habitat had a higher prevalence of Controrchis biliophilus. A. p. mexicana individuals had a higher prevalence of Trypanoxyuris minutus than A. pigra, probably the result of the larger group sizes found in the former species, and T. minutus was more likely to be found in A. palliata individuals that lived in fragmented habitat. Adult A. p. mexicana males had a higher risk of being parasitized compared to adult females, but these differences were not detected in A. pigra, Parasite species such as Entamoeba sp., Nematoda sp. 28, Nematoda sp. B and Parabronema sp. where only found during the wet season in both howler monkey species. Populations of both howler monkey species had a higher prevalence of Nematoda sp. A in the wet season and Ascaridae eggs were only detected during the wet season in A. pigra. Other parasites detected displayed no clear seasonal pattern [Current Zoology 58 （3）： 375-383, 2012].展开更多
文摘The publisher regrets that the article type for this publication was incorrectly labeled as a Research Article.The correct designation should be Review Article.This correction does not affect the content or conclusions of the article.The publisher apologizes for any inconvenience caused.
基金Supported by the JSPS KAKENHI,No.JP21K10300 and No.JP24K02714.
文摘BACKGROUND Early diagnosis of left ventricular diastolic dysfunction(LVDD)is essential for preventing heart failure.B-type natriuretic peptide(BNP)is a viable marker for predicting LVDD,as elevated BNP levels have been associated with worsening LVDD in patients with diabetes over time.However,the utility of BNP as a diagnostic marker in diabetes is controversial,as BNP levels are often low in overweight individuals.AIM To examine the effectiveness of BNP levels and fragmented QRS(fQRS)on electrocardiography for diagnosing LVDD in patients with type 2 diabetes.METHODS This retrospective cohort study included 303 patients with type 2 diabetes(67.4±12.3 years old)with preserved ejection fraction(EF)≥50%admitted to Toyama University Hospital for glycemic management and comorbidity evaluation between November 2017 and April 2021.All participants underwent plasma BNP measurement,electrocardiography,and echocardiography.Cardiologists who were blinded to the BNP results assessed the electrocardiograms and echocardiograms.Subgroup analyses were conducted for overweight individuals.RESULTS Receiver operating characteristic(ROC)curve analysis determined optimal BNP cut-off values of 34.8 pg/mL and 7.2 pg/mL for diagnosing LVDD in non-overweight[area under the ROC curve(AUC):0.70]and overweight(AUC:0.55)groups,respectively(P=0.040).In the overweight subgroup,fQRS showed greater diagnostic accuracy for LVDD(AUC:0.67),indicating moderate diagnostic utility compared with the low performance of the BNP cutoff of 35 pg/mL(AUC:0.52)(P=0.010).Multivariate analyses confirmed that fQRS was superior to BNP for LVDD diagnosis regardless of the patient’s weight.CONCLUSION A BNP level≥35 pg/mL in non-overweight individuals may be a reliable LVDD marker.Additionally,fQRS was more effective than BNP in diagnosing LVDD irrespective of the patient’s weight.fQRS can complement BNP in the early detection of LVDD,especially in overweight patients,potentially improving early detection and mitigating progression to heart failure with preserved EF in patients with type 2 diabetes.
文摘BACKGROUND The microcystic,elongated,and fragmented(MELF)pattern of invasion in endometrioid endometrial carcinoma(EEC)is a special mode of myometrial invasion that has been recently recognized by the pathology community.Overex-pression of CXC chemokine receptor 4(CXCR4)in tumor cells contributes to tumor growth,invasion,angiogenesis,metastasis,and recurrence.AIM To explore the correlation between CXCR4 expression in EEC and MELF invasion and clinicopathological features.METHODS A total of 205 EEC patients treated at Peking University People’s Hospital from June 2020 to December 2021 were selected(60 cases with MELF invasion,145 cases without).The clinicopathological features of the two groups were compared,and expression of CXCR4 protein,estrogen receptor,and progesterone receptor was detected and compared by immunohistochemistry.RESULTS EEC with MELF invasion was significantly associated with low tumor grade,lymphovascular space invasion,deep myometrial invasion,cervical stromal involvement,and lymph node metastasis.There was a difference in CXCR4 expression between the two groups,with the MELF group having a significantly higher expression than the non-MELF group.CONCLUSION CXCR4 expression is significantly increased in EEC with MELF invasion and in the MELF invasion area,which may promote tumor invasion and metastasis and has some value for prognostic assessment.
基金supported by the National Natural Science Foundation of China(Grant No.12474159)the Fundamental Research Funds for the Central University,Sun Yat-sen University(Grant No.24qnpy119)the China Postdoctoral Science Foundation(Grant No.2024T171067)。
文摘We investigate distinct non-Hermitian skin effects(NHSEs)in real and Fock spaces induced by the interplay between the Hilbert space fragmentation and multiple non-Hermitian pumping channels.Using an extended Hatano–Nelson model with next-nearest neighbor hopping and strong interaction as an example,we found that two fermions loaded in the lattice exhibit different real-space NHSE depending on the Hilbert space fragments to which they belong.Moreover,in the high-energy sector resulting from fragmentation,the two-particle-bound states form a one-dimensional lattice in Fock space,producing a Fock-space NHSE.At half-filling,richer patterns of Fock-space skin-like localization emerge for the different fragmented energy sectors and subsectors while realspace NHSE is suppressed by many-body effects.This study extends our understanding of the interplay between NHSE and Hilbert space fragmentation and provides detailed insights into their manifestation in interacting non-Hermitian systems.
基金funded by the National Natural Science Foundation of China (Grant Nos.12302444 and 12202349)。
文摘An in-depth understanding of the fracture behavior and mechanism of metallic shells under internal explosive loading can help develop material designs for warheads and regulate the quantity and mass distribution of the fragments formed.This study investigated the fragmentation performance of a new high-carbon silicon-manganese(HCSiMn)steel cylindrical shell through fragment recovery experiments.Compared with the conventional 45Cr steel shell,the number of small mass fragments produced by the HCSi Mn steel shell was significantly increased with a scale parameter of 0.57 g fitted by the Weibull distribution model.The fragmentation process of the HCSi Mn shell exhibited more brittle tensile fracture characteristics,with the microcrack damage zone on the outer surface being the direct cause of its high fragmentation.On the one hand,the doping of alloy elements resulted in grain refinement by forming metallographic structure of tempered sorbite,so that microscopic intergranular fracture reduces the characteristic mass of the fragments;on the other hand,the distribution of alloy carbides can exert a"pinning"effect on the substrate grains,causing more initial cracks to form and propagate along the brittle carbides,further improving the shell fragmentation.Although the killing power radius for light armored vehicles was slightly reduced by about 6%,the dense killing radius of HCSiMn steel projectile against personnel can be significantly increased by about 26%based on theoretical assessment.These results provided an experimental basis for high fragmentation warhead design,and to some extent,revealed the correlation mechanism between metallographic structure and shell fragmentation.
基金Project supported by the National Science & Technology Pillar Program during the 12th Five-Year Plan Period(No.2011BAI11B06),China
文摘This study is aimed to investigate the clinical significance and the short-term prognostic value of frag- mented QRS （fQRS） for patients with acute myocardial infarction （AMI）. Three hundred patients with AMI were tested with retrospective analysis on the patients＇ clinical information, hospitalized treatment, fQRS onset time, location of lesions, and other relevant data, in order to assess the relationship between the presence of fQRS and its prognosis. The rates of malignant cardiac arrhythmia, left ventricular systolic dysfunction （LVSD）, and mortality in the positive fQRS group were 13.6%, 29.2%, and 23.7%, respectively, with all showing a p value 〈0.05. For the ST segment elevation myocardial infarction （STEMI） subgroup, all the rates showed significant differences with a p value 〈0.01, while for the non-STEMI （NSTEMI） subgroup showed no significant differences. In patients with a positive fQRS, there were no differences in malignant cardiac arrhythmia between patients with and without percutaneous coronary in- tervention （PCI） （p〉0.05）. As for the LVSD and mortality, the p values between patients with and without PCI were 0.031 and 0.000, respectively, suggesting statistical significance. The results imply that AMI patients with positive fQRS especially for the patients with STEMI had higher rates of malignant cardiac arrhythmia, LVSD, and mortality than the non-fQRS group. Patients of AMI with positive fQRS, who underwent early revascularization, could lower the incidence of the cardiovascular event. In addition, the presence of fQRS could be used as an indication of early in- tervention treatment for patients.
文摘Objective To describe the clinical characteristics of idiopathic ventricular fibrillation （IVF） with fragmented QRS complex （f-QRS） and J wave in resting electrocardiogram. Methods We reviewed data from 21 case subjects in our hospital who were resuscitated after cardiac arrest due to IVF and assessed the prevalence of f-QRS and J wave in resting electrocardiogram （ECG）. All the case subjects were classified among three groups based on the electrocardiographic morphology： group I, both f-QRS and J wave were observed （n = 6）, group II, only J wave was observed （n = 9）, group III, neither f-QRS nor J wave was observed （n = 6）. Population characteristics, history of syncope or sudden cardiac arrest, incidence of ventricular fibrillation （VF）, and circumstance of VF were evaluated among the three groups. Results The incidence of index events （syncope, survived cardiac arrest and VF episodes recorded in implantable cardioverter defibrillator （ICD） or pacemakers） was 13.4 ~ 5.6 per-year in group I, 10.8 ~ 3.9 per-year in group II, and 9.8 -4- 4.2 per-year in group HI. There were significant differences in incidences among the three groups, the most frequent index events were observed in group I. The hazard ratio for incidence was 3.2 （95%CI, 1.1-7.9; P = 0.01）. The history and circumstance of the index events were different among the groups. In group I, all the index events occurred during sleep in early morning. In group II, four subjects suffered VF during strenuous physical activities or agitation state, two during sleep in early morning, three in usual activity. In group III, one subject suffered VF during sleep in early morning, one in agitation state, four in usual activity. Conclusions This study suggests that the IVF patients with the combined appearance of f-QRS and J wave in the resting ECG suffer an increased risk of VF, this subgroup of IVF patients has a unique clinical feature.
文摘The road effect on small rodent population is investigated at 8 fragmented forest areas in the Baekdudaegan mountain range, South Korea in September 2001. We especially focused on the distribution and body condition of small rodents near the roads. Korean field mouse (Apodemus peninsulae) seems to be more sensitive to the existence of a road than striped field mouse (Apodemus agrarius). Korean field mouse prefers interior forest area to around road. Striped field mouse is a habitat generalist and has wide distributional range around road, but Korean field mouse is forest-inhabiting species and their distribution is limited in forest area. These results suggest the effect of road is different on each small rodent species and their habitat preferences.
基金Supported by Research Project on Education and Teaching Reform of Higher Education Institutions in Hainan Province(Hnjg2016-12)Education and Teaching Reform Research Project of Hainan University(hdjy1604)
文摘The development of information technology has changed people's learning methods. Fragmented learning,as an informal learning method,has become an important way to accept new knowledge and learn new technologies. Through analyzing the connotation,characteristics,and advantages and disadvantages of fragmented learning,this paper came up with reasonable recommendations for fragmented learning. To truly become systematic and holistic knowledge,fragmented knowledge must be explored,understood,integrated and internalized. This paper is expected to play an important guiding role in building a lifelong learning society.
基金This study was supported by the National Natural Science Foundation of China(Grant No.31700468)the Natural Science Foundation of Jiangsu Province(Grant No.BK2017636).
文摘Background:Remnant microhabitats are important for bird habitat selection and plant regeneration in the fragmented habitat.However,empirical information on the consequences of how microhabitat use by birds affects the early recruitment of plants is lacking.Methods:In this study,we evaluated whether microhabitat selection by the Black Bulbul(Hypsipetes leucocephalus)(J.F.Gmelin,1789)impacts the early recruitment of the endangered tree species,the Chinese Yew(Taxus chinensis(Pilger)Rehd),in a fragmented forest over a 4-year period(2011–2012,2018–2019).Results:Our results showed the main factors affecting H.leucocephalus microhabitat selection were distance to the nearest T.chinensis mature tree,herb cover and density,leaf litter cover,and vegetation type.Moreover,the results of logistic regression also highlighted the importance of elevation,distance to light gap and roads,tree cover in bird microhabitat selection.Furthermore,the seed emergence rate in microhabitats used by birds did not differ from the natural forest,which was related to five factors of bird microhabitat.The Random Forest model showed that seedling emergence rate was increased with leaf litter cover and distance to fallen dead trees,but decreased in relation to herb cover,slope,and elevation.Conclusion:Our results highlight the importance of remnant microhabitats in fragmented forests for sustaining forest ecology and optimal management.The contribution of microhabitats used by birds to plant recruitment provides insights into how frugivore species contribute to plant regeneration,which should be incorporated in future conservation and management practices of fragmented forests.
文摘Background: Patients requiring valve replacement at a younger age, for rheumatic heart disease was apparently increasing after the new age practice of contraception. Methods: In 2012, data of patients referred to tertiary care hospital from two cardiology screening camps conducted in the community, were analyzed for the severity of presentation of rheumatic heart disease and associated contraception status by dividing into the three age groups—20 - 35 years, 36 - 50 years, >51 years;~400 patients attended the camps;31 female and 2 male patients were referred to the tertiary care hospital for further evaluation and categorized treatment, including valve replacement surgeries;among the 33 referred patients, belonging to the three age groups, the data were analyzed for [if any] correlation of contraception status with severe rheumatic heart disease. 8 randomly chosen males, of the 3 age groups, from a different community, whose life partners had undergone sterilization, were assessed for their serum testosterone levels. Results: Among 20 - 35 years, 7 female patients with contraception required valve replacement surgeries [p 51 years, 3 female and 2 male patients without contraception received medical treatment only
文摘In the era of new media,people’s lifestyle,education and the like are inseparable from the Internet.At the same time,due to the emergence of smart devices such as mobile phones and tablet computers,people’s reading habits have changed.Fragmented reading has become an important form of reading for college students.College students themselves have the strong ability to accept change,so fragmented reading has gradually become an important form of student learning.This paper mainly analyses fragmented reading by college students and its impact on society in the era of new media.
基金This paper was supported by“the National Social Science Fund of China”(Grant Number:17BYY098).
文摘This paper attempts to investigate the feasibility and learning effects of English fragmented learning via mobile devices.Questionnaires and interviews were employed to do the survey on 157 undergraduates from 24 universities in China.The research findings reveal that English fragmented learning via mobile devices has some positive effects on the improvement of learners’knowledge and learning ability.In addition,there have been a certain number of useful learning resources and platforms with diversified features.The study has the implications that fragmented mobile learning is feasible and can be popularized in English learning.
文摘Background Based on previous studies, a fragmented QRS （fQRS） complex, as a predictive biomarker of myocardial scarring condition, could be used to predict the outcomes of cardiac resynchronized therapy （CRT）. However, this conclusion is still debatable. Methods Fifty ischemic or non-ischemic cardiomyopathy patients failure （aged 65 ± 10 yrs, 34 males, 16 females） with refractory heart, diagnosed by the criteria of New York Heart Association received CRT. The ECGs of 18 patients with a fQRS complex （divided by Das） were compared with those of 32 patients without a fQRS complex, who were evaluated by 12-lead ECG before CRT. The patients were followed up for six months, and 12-lead ECG and echocardiography were reviewed. At least 15% reduction in the left ventricular end-systolic volume （LVESV） was defined as responders according to the data obtained for between-group and intra-group analysis. Results Six patients （33.3%） in the fQRS group and 24 patients （75%） in the non-fQRS group responded well. In addition, comparisons of indicators from surface ECG and echocardiography 6 months after CRT showed that the non-fQRS group benefited from CRT significantly more than the fQRS group. Conclusions The fQRS complex has good predictive value for responsiveness to CRT. Non-fQRS complex patients with refractory heart failure may benefit more from CRT, and these patients need to receive this treatment as early as possible.
基金supported by the National Natural Science Foundation of China(Grant No.31270468,30620130110)
文摘The Chinese Grouse (Tetrastes sewerzowi) is a rare, endemic bird in China, inhabiting conifer-dominated mountain forests. Both the natural fragmentation and heavy cutting of mature forests have resulted in patchy grouse habitats. We used SPOT (XS-sensor) satellite imagery to discriminate between open land and conifer or broadleaf forests. The area analyzed is about 120000 ha in size and includes the Lianhuashan Nature Reserve and the Yeliguan Forestry Park. We identiifed 4111 ha of mature coniferous forests in 229 patches (maximum 332 ha, mean 18 ha) as the habitat used by Chinese Grouse throughout the year. We examined 31 forest islands of different sizes and degrees of isolation for the presence of Chinese Grouse. We used generalized linear models (GLM) with binomial error structure and logit link function to estimate the probability of Chinese Grouse occupancy in a forest fragment. Habitat patch size (hs) and distance to the next occupied fragment (doc) were used as predictor variables, important for occupancy. Small habitat islands were disproportionately less likely to be occupied than large, nearby habitats. There was a clear speciifc habitat size of about 40 ha, above which habitat fragments were occupied more often. Suitable habitat fragments isolated by more than 2 km appeared to be inaccessible to Chinese Grouse. The results have been used in reforestation projects to establish linking corridors in the study area.
文摘OCTOBER 25 is Central African Regional Integration Day. Few people know or observe this holiday because the citizens of Africa＇s poorest and most conflict-prone region have little to celebrate.
基金Under the auspices of Major State Basic Research Development Program of China (973 Progrom) (No 2007CB106801)National Key Technology R&D Program of China (No 2006BAD16B06)National Natural Science Foundation of China (No 30470180,30770397)
文摘A number of isolated islands of Leymus chinensis ＋ herbosa community were investigated in fragmented habitat islands, by Braun-Blanquet field survey approach, in a degenerated meadow in the Songnen Plain, China in 2007. These islands were classified as large, medium, and small scales on the basis of the island area （100-1000m2, large island; 50-100m2, middle island; 10-50m2, small island）. Each scale of the investigation involved eight islands. The responses ofβ-diversity patterns of plant taxon to the habitat fragmentation at local community and metacommunity levels were analyzed on different scales of 24 isolated islands. The results indicated that at the local community level, there were 57 species belonging to 20 families and 49 genera in large islands, 49 species belonging to 16 families and 40 genera in middle islands, and 27 species belonging to eight families and 23 genera in small islands, β-diversity indexes for species, genus and family in large, middle, and small islands varied greatly, and the highest value of the indexes was not noted in the largest island. However, the average of the data obtained at the three scales showed that across large islands, Whittaker indexes were low and Bray-Curtis similarity indexes were high, while across small islands, Whittaker indexes were high and Bray-Curtis similarity indexes were low. At the metacommunity level, Whittaker indexes for species and genus showed a great significantly negative double logarithmic correlation （p〈0.01） with the island area, whereas the Bray-Curtis indexes for species, genus and family showed a great significantly positive double logarithmic correlation （p〈0.01） with the island area. At both local community and metacommunity levels, tumovers of species and genus could respond more sensitively to spatial changes of plant diversity patterns than that of family. Hence, the species and the genus could be used for the analysis offl-diversity patterns of plant community.
基金supported by the University Grants Commission(UGC)(Grant no.:F1-17.1/2013-14/RGNF-2013-14-STNAG-43868/(SA-III/website)and(Grant no.F.15-6(Dec.,2011)/2012(NET))。
文摘The population structure and regeneration status of Magnolia punduana Hk. f. & Th., an endemic tree species of northeast India were investigated in fragmented forests in the Jarain Hills and in adjoining areas of Meghalaya state. The population structure was discontinuous in all the fragments with the absence of individuals in higher diameter classes. The number of individuals increased with the size of the fragment patches(p < 0.004). The density of mature trees(≥5 cm dbh) was high(24–30 individuals ha-1) in the largest fragment(>105 ha). The number of seedlings and saplings were also higher in the larger fragments. Human-related disturbances had a negative impact on the species population(p<0.002). Variation in the population density in different forest patches has been attributed to fragment size, site characteristics and ongoing human disturbances. The restricted distribution of the species coupled withexploitation and habitat destruction underlines the need for its conservation.
文摘In this study we document the prevalence of gastrointestinal parasites （helminths and protozoans） found in fecal samples of populations of Alouatta palliata mexicana and ofA. pigra in Los Tuxtlas and in Palenque, southeast Mexico, and its re- lation to habitat condition, sex/age and season. Nineteen parasite morphotypes were detected in the fecal samples from populations of the two howler monkeys, of which 58% were shared by both species. When considering all parasite species, populations of the two howler species were more likely to be parasitized in fragmented habitat compared to continuous habitat. Individuals of both howler monkey species that lived in fragmented habitat had a higher prevalence of Controrchis biliophilus. A. p. mexicana individuals had a higher prevalence of Trypanoxyuris minutus than A. pigra, probably the result of the larger group sizes found in the former species, and T. minutus was more likely to be found in A. palliata individuals that lived in fragmented habitat. Adult A. p. mexicana males had a higher risk of being parasitized compared to adult females, but these differences were not detected in A. pigra, Parasite species such as Entamoeba sp., Nematoda sp. 28, Nematoda sp. B and Parabronema sp. where only found during the wet season in both howler monkey species. Populations of both howler monkey species had a higher prevalence of Nematoda sp. A in the wet season and Ascaridae eggs were only detected during the wet season in A. pigra. Other parasites detected displayed no clear seasonal pattern [Current Zoology 58 （3）： 375-383, 2012].
