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Peat properties of a tropical forest reserve adjacent to a fire-break canal
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作者 Dayang Nur Sakinah Musa Mohd Zahirasri Mohd Tohir +3 位作者 Xinyan Huang Luqman Chuah Abdullah Mohamad Syazaruddin Md Said Muhammad Firdaus Sulaiman 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期155-167,共13页
Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit gr... Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit greenhouse gases and particles contributing to haze,and prevention by constructing fire-break canals to reduce fire spread into forest reserves is crucial.This paper aims to determine peat physical and chemical properties near a fire-break canal at different fire frequency areas.Peat sampling was conducted at two forest reserves in Malaysia which represent low fire frequency and high fire frequency areas.The results show that peat properties were not affected by the construction of a fire-break canal,however lignin and cellulose content increased significantly from the distance of the canal in both areas.The study concluded that fire frequency did not significantly influence peat properties except for porosity.The higher fibre content in the high frequency area did not influence moisture content nor the ability to regain moisture.Thus,fire frequency might contribute differently to changes in physical and chemical properties,hence management efforts to construct fire-break canals and restoration efforts should protect peatlands from further degradation.These findings will benefit future management and planning for forest reserves. 展开更多
关键词 Peat fire Peat properties Fire-break canals Forest reserves
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Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China
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作者 ZHU Haiqiang WANG Jinlong +2 位作者 TANG Junhu DING Zhaolong GONG Lu 《Journal of Arid Land》 SCIE CSCD 2024年第6期816-833,共18页
Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,i... Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China. 展开更多
关键词 net primary productivity(NPP) water yield soil conservation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model geographic detector Tianchi Bogda Peak Natural reserve
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Swelling pressure evolution characterization of strong expansive soil considering the influence of reserved expansion deformation
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作者 LI Tianguo KONG Lingwei +1 位作者 GUO Aiguo YAN Junbiao 《Journal of Mountain Science》 SCIE CSCD 2024年第1期252-270,共19页
Numerous engineering cases have demonstrated that the expansive soil channel slope remains susceptible to damage with the implementation of a rigid or closed protective structure. It is common for the protective struc... Numerous engineering cases have demonstrated that the expansive soil channel slope remains susceptible to damage with the implementation of a rigid or closed protective structure. It is common for the protective structure to experience bulging failure due to excessive swelling pressure. To investigate the swelling pressure properties of expansive soil, the constant volume test was employed to study the influence of water content and reserved expansion deformation on the characteristics of swelling pressure in strong expansive soils, and also to explore the evolution mechanism of the swelling pressure. The findings demonstrate that the swelling pressure-time curve can be classified into swelling pressure-time softening and swelling pressure-time stability type. The swelling pressuretime curve of the specimen with low water content is the swelling pressure-time softening type, and the softening level will be weakened with increasing reserved expansion deformation. Besides, the maximum swelling pressure Psmax decreases with increasing water content and reserved expansion deformation, especially for expansion ratio η from 24% to 37%. The reserved deformation has little effect on reducing Psmax when it is beyond 7% of the expansion rate. The specimen with low water content has a more homogeneous structure due to the significant expansion-filling effect, and the fracture and reorganization of the aggregates in the specimens with low water content cause the swelling pressure-time softening behavior. In addition, the proposed swelling pressure-time curve prediction model has a good prediction on the test results. If necessary, a deformation space of about 7% expansion rate is recommended to be reserved in the engineering to reduce the swelling pressure except for keeping a stable water content. 展开更多
关键词 Expansive soil Swelling pressure reserved expansion deformation Water content
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Efficacy of intraovarian autologous platelet-rich plasma administration in women with low ovarian reserve: A systematic review and meta-analysis
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作者 Yasmin Sabina Sa’diah Agung Dewanto Lukman A Chandra 《Asian pacific Journal of Reproduction》 CAS 2024年第2期60-67,共8页
Objective:To conduct a systematic examination and meta-analysis of the most reliable data from experimental studies evaluating the efficacy of autologous platelet-rich plasma(PRP)on low ovarian reserve.Methods:A compr... Objective:To conduct a systematic examination and meta-analysis of the most reliable data from experimental studies evaluating the efficacy of autologous platelet-rich plasma(PRP)on low ovarian reserve.Methods:A comprehensive search was performed utilizing pertinent search terms across electronic databases,including PubMed,Cochrane,and Google Scholar.We included studies that assigned infertile women with low ovarian reserve in experimental studies.Ovarian reserve parameters were measured before and after PRP injection into ovaries.The data of each study was retrieved and subsequently compiled.Results:Of 301 articles collected and reviewed,six studies were finally included in the meta-analysis.Following PRP injection,infertile women showed a non-significant increase in anti-Mullerian hormone(AMH)level(MD=0.10;95%CI-0.04,0.23),a significant increase in antral follicular count(AFC)(MD=1.88;95%CI 0.47,3.29),and a non-significant reduction in follicle-stimulating hormone(FSH)level(MD=-0.22;95%CI-8.32,7.87).Conclusions:Autologous PRP may increase AFC,but not AMH.Although it is found beneficial in enhancing ovarian reserve(AFC),further research with strong evidence is still required. 展开更多
关键词 Platelet-rich plasma Low ovarian reserve Ovarian rejuvenation
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Association between people’s attitudes towards human-elephant conflict and their locational,demographic,and socio-economic characteristics in Buxa Tiger Reserve and its adjoining area,India
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作者 Chiranjib NAD Tamal BASU-ROY 《Regional Sustainability》 2024年第1期11-25,共15页
“Human-elephant conflict(HEC)”,the alarming issue,in present day context has attracted the attention of environmentalists and policy makers.The rising conflict between human beings and wild elephants is common in Bu... “Human-elephant conflict(HEC)”,the alarming issue,in present day context has attracted the attention of environmentalists and policy makers.The rising conflict between human beings and wild elephants is common in Buxa Tiger Reserve(BTR)and its adjoining area in West Bengal State,India,making the area volatile.People’s attitudes towards elephant conservation activity are very crucial to get rid of HEC,because people’s proximity with wild elephants’habitat can trigger the occurrence of HEC.The aim of this study is to conduct an in-depth investigation about the association of people’s attitudes towards HEC with their locational,demographic,and socio-economic characteristics in BTR and its adjoining area by using Pearson’s bivariate chi-square test and binary logistic regression analysis.BTR is one of the constituent parts of Eastern Doors Elephant Reserve(EDER).We interviewed 500 respondents to understand their perceptions to HEC and investigated their locational,demographic,and socio-economic characteristics including location of village,gender,age,ethnicity,religion,caste,poverty level,education level,primary occupation,secondary occupation,household type,and source of firewood.The results indicate that respondents who are living in enclave forest villages(EFVs),peripheral forest villages(PFVs),corridor village(CVs),or forest and corridor villages(FCVs),mainly males,at the age of 18–48 years old,engaged with agriculture occupation,and living in kancha and mixed houses,have more likelihood to witness HEC.Besides,respondents who are illiterate or at primary education level are more likely to regard elephant as a main problematic animal around their villages and refuse to participate in elephant conservation activity.For the sake of a sustainable environment for both human beings and wildlife,people’s attitudes towards elephants must be friendly in a more prudent way,so that the two communities can live in harmony. 展开更多
关键词 Human-elephant conflict Elephant conservation Chi-square test statistics Binary logistic regression Demographic and socioeconomic characteristics Buxa Tiger reserve
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Interaction between catechol-O-methyltransferase Val/Met polymorphism and cognitive reserve for negative symptoms in schizophrenia
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作者 Wen-Peng Hou Xiang-Qin Qin +6 位作者 Wei-Wei Hou Yun-Yi Han Qi-Jing Bo Fang Dong Fu-Chun Zhou Xian-Bin Li Chuan-Yue Wang 《World Journal of Psychiatry》 SCIE 2024年第5期695-703,共9页
BACKGROUND Cognitive reserve(CR)and the catechol-O-methyltransferase(COMT)Val/Met polymorphism are reportedly linked to negative symptoms in schizophrenia.However,the regulatory effect of the COMT genotype on the rela... BACKGROUND Cognitive reserve(CR)and the catechol-O-methyltransferase(COMT)Val/Met polymorphism are reportedly linked to negative symptoms in schizophrenia.However,the regulatory effect of the COMT genotype on the relationship between CR and negative symptoms is still unexamined.AIM To investigate whether the relationship between CR and negative symptoms could be regulated by the COMT Val/Met polymorphism.METHODS In a cross-sectional study,54 clinically stable patients with schizophrenia underwent assessments for the COMT genotype,CR,and negative symptoms.CR was estimated using scores in the information and similarities subtests of a short form of the Chinese version of the Wechsler Adult Intelligence Scale.RESULTS COMT Met-carriers exhibited fewer negative symptoms than Val homozygotes.In the total sample,significant negative correlations were found between negative symptoms and information,similarities.Associations between information,similarities and negative symptoms were observed in Val homozygotes only,with information and similarities showing interaction effects with the COMT genotype in relation to negative symptoms(information,β=-0.282,95%CI:-0.552 to-0.011,P=0.042;similarities,β=-0.250,95%CI:-0.495 to-0.004,P=0.046).CONCLUSION This study provides initial evidence that the association between negative symptoms and CR is under the regulation of the COMT genotype in schizophrenia. 展开更多
关键词 Catechol-O-methyltransferase Val/Met polymorphism Cognitive reserve Crystallized intelligence Negative symptoms SCHIZOPHRENIA
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Clinical application of reserved gastric tube in neuroendoscopic endonasal surgery for pituitary tumor
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作者 Xi Chen Long-Yao Zhang +3 位作者 Zhi-Feng Wang Yi Zhang Yu-Hua Yin Xue-Jian Wang 《World Journal of Clinical Oncology》 2024年第3期411-418,共8页
BACKGROUND The neuroendoscopic approach has the advantages of a clear operative field,convenient tumor removal,and less damage,and is the development direction of modern neurosurgery.At present,transnasal surgery for ... BACKGROUND The neuroendoscopic approach has the advantages of a clear operative field,convenient tumor removal,and less damage,and is the development direction of modern neurosurgery.At present,transnasal surgery for sphenoidal pituitary tumor is widely used.But it has been found in clinical practice that some patients with this type of surgery may experience post-operative nausea and vomiting and other discomforts.AIM To explore the effect of reserved gastric tube application in the neuroendoscopic endonasal resection of pituitary tumors.METHODS A total of 60 patients who underwent pituitary adenoma resection via the endoscopic endonasal approach were selected and randomly divided into the experimental and control groups,with 30 in each group.Experimental group:After anesthesia,a gastric tube was placed through the mouth under direct vision using a visual laryngoscope,and the fluid accumulated in the oropharynx was suctioned intermittently with low negative pressure throughout the whole process after nasal disinfection,during the operation,and when the patient recovered from anesthesia.Control group:Given the routine intraoperative care,no gastric tube was left.The number of cases of nausea/vomiting/aspiration within 24 h post-operation was counted and compared between the two groups;the scores of pharyngalgia after waking up,6 h post-operation,and 24 h postoperation.The frequency of postoperative cerebrospinal fluid leakage and intracranial infection were compared.The hospitalization days of the two groups were statistically compared.RESULTS The times of postoperative nausea and vomiting in the experimental group were lower than that in the control group,and the difference in the incidence of nausea was statistically significant(P<0.05).After the patient woke up,the scores of sore throat 6 h after the operation and 24 h after operation were lower than those in the control group,and the difference was statistically significant(P<0.05).The number of cases of postoperative cerebrospinal fluid leakage and intracranial infection was higher than that of the control group,but there was no statistically significant difference from the control group(P>0.05).The hospitalization days of the experimental group was lower than that of the control group,and the difference was statistically significant(P<0.05).CONCLUSION Reserving a gastric tube in the endoscopic endonasal resection of pituitary tumors,combined with intraoperative and postoperative gastrointestinal decompression,can effectively reduce the incidence of nausea,reduce the number of vomiting and aspiration in patients,and reduce the complications of sore throat The incidence rate shortened the hospitalization days of the patients. 展开更多
关键词 NEUROENDOSCOPY Endonasal approach Pituitary tumor reserved gastric tube NAUSEA VOMITING ASPIRATION COMPLICATIONS
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Many Kinds of Reserved Judgement in No-Data Problem
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作者 Houju Hori Jr. 《Applied Mathematics》 2024年第1期1-8,共8页
The reserved judgment can be broadly categorized into three types: Re-Do, Re-Set, and Natural Flowing Case (i.e. step by step in Re-Try). Hori et al. constructed the Bayes-Fuzzy Estimation and demonstrated that system... The reserved judgment can be broadly categorized into three types: Re-Do, Re-Set, and Natural Flowing Case (i.e. step by step in Re-Try). Hori et al. constructed the Bayes-Fuzzy Estimation and demonstrated that system theory can be applied to the possibility of Markov processes, and that decision-making approaches can be applied to sequential Bayes estimation. In this paper, we focus on the Natural Flowing Case within reserved judgment. Here, the possibility of oblique (or principal) factor rotation is considered as a part of the tandem fuzzy system that follows step by step for sequential Bayes estimation. Ultimately, we achieve a significant result whereby the expected utility can be calculated automatically without the need to construct a utility function for reserved judgment. There, this utility in Re-Do can be calculated by the prior utility, and that utility in Re-set does not exist by our research in this paper. Finally, we elucidate the relationship between fuzzy system theory and fuzzy decision theory through an applied example of Bayes-Fuzzy theory. Fuzzy estimation can be applied to only normal making decision, but it is impossible to apply abnormal decision problem. Our Vague, specially Type 2 Vague can be applied to abnormal case, too. 展开更多
关键词 Bayes-Fuzzy Estimation Re-Do Re-Set Indifferent Zone reserved Judgement
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Ovarian Reserve in a Population of Obese Infertile Patients in Kinshasa
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作者 Charlie-Junior Bikuelo Bikuelo Dan Ngoyi Kabengele +6 位作者 Justin Mboloko Esimo Athéna Mwakila Asana Guy Monzango Sibo Charles Moangi Bapanzi Patrick Mogwo Sendeke Pathou Mampuya Ipanga Annie Egbolo Azima 《Open Journal of Obstetrics and Gynecology》 2024年第10期1657-1669,共13页
Background: The ovarian reserve, which is an important marker in the management of couple infertility, undergoes depletion over time. This depletion could accelerate in the presence of certain circumstances, such as o... Background: The ovarian reserve, which is an important marker in the management of couple infertility, undergoes depletion over time. This depletion could accelerate in the presence of certain circumstances, such as obesity. The contradictory results of studies on the impact of obesity on the ovarian reserve throughout the world accelerated ovarian ageing in infertile women from Kinshasa, as well as the high rate of obese women in this population, seemed necessary to undertake this study to find out if this obesity impacted the ovarian reserve of Kinshasa women. The objective of this study was to identify the profile of markers of ovarian reserve in obese infertile patients according to certain characteristics. Method: A case-control study with retrospective data collection on 439 obese infertile patients (cases) and 439 normal-weight infertile patients (controls) who had consulted for the desire to conceive at the University Hospital of Kinshasa and the Edith Medical Center between January 2016 and December 2021. Results: The average age of the patients was 33.6 years ± 4.3 years, with 47.8% of patients aged at least 35 years. Menarche and menstrual duration were correlated with AMH in linear regression (p = 0.043 and 0.021, respectively). Late menarche and irregular cycle were risk factors for ovarian ageing [OR: 4.6;95% CI: (1.052 - 20.636);p = 0.043 and OR: 4.8;95% CI: (1.633 - 14.566);p = 0.005] while PCO was a protective factor for ovarian ageing [OR: 0.109;95% CI: (0.182 - 0.652);p = 0.015]. Conclusion: Within the limits of our study, we found that the more obese the patients were, the faster the ovaries aged. 展开更多
关键词 Ovarian reserve Obesity INFERTILITY AMH FSH
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Seasonal Abundance and Diversity of Birds of Prey and Owls in Al Wathba Wetland Reserve in Abu Dhabi, UAE
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作者 Shakeel Ahmed Salim Jáved +3 位作者 Shahid B. Khan Eissa Al Hammadi Abdullah Al Hammadi Nouf Sameer Alqadi 《Open Journal of Ecology》 2024年第3期228-244,共17页
Inland wetlands in Abu Dhabi Emirate are wintering and stopover sites for migratory birds of prey. We conducted long-term regular monitoring surveys in Al Wathba Wetland Reserve (AWWR) from January 1995 to December 20... Inland wetlands in Abu Dhabi Emirate are wintering and stopover sites for migratory birds of prey. We conducted long-term regular monitoring surveys in Al Wathba Wetland Reserve (AWWR) from January 1995 to December 2022. Both diurnal and occasionally nocturnal surveys were undertaken to record the migratory raptors and owls in the Wetland Reserve. During the study, a total of 1282 regular monitoring visits were undertaken and 27 species of diurnal raptors and owls representing five families and three orders were detected. These represent 57% of the total species of birds of prey recorded in the UAE. Overall, 63% of all the species that we observed were Accipitriformes followed by 26% Falconiformes and 11% Strigiformes. We found that changes in mean daily temperature have a positive effect on raptor species diversity and abundance in the Wetland Reserve. The species encounter rate was higher in low temperature as compared to high temperature and overall regression equation was statistically significant F (4, 1126) = 8.49), p = 0.00). However, the numbers of raptors did not vary significantly across the years (p = 0.51). Western Marsh-harrier (Circus aeruginosus) and Greater Spotted Eagle (Clanga clanga) were recorded to be the most abundant species in the wetland reserve followed by Common Kestrel (Falco tinnunculus). However, the encounter rate of globally threatened Greater Spotted Eagle was detected to have significantly decreased since 2016. Moreover, 63% of the species detected were uncommon and rarely recorded such as 1) Saker Falcon 2) Lanner Falcon 3) Long-eared Owl & Merlin, which were the rare records from the wetland reserve. Furthermore, 27 years of regular monitoring in the wetland have yielded diverse diurnal raptors and owl fauna (H) = 0.83, (E) = 1.43 (Shannon Diversity Index). The results demonstrate that long-term monitoring surveys in arid environments are essential to determine the trends in the raptor populations and to document rare and globally important species. 展开更多
关键词 Wetland reserve RAPTORS Abundance DIVERSITY Abu Dhabi Inland Wetland AWWR Greater Spotted Eagle
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Impacts of Human Activities and Season on Species Diversity and Abundance of Butterflies in Mpanga Kipengere Game Reserve and Surrounding Farmlands, Tanzania
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作者 Privatus M. Kasisi Nsajigwa Mbije Paul Lyimo 《Open Journal of Ecology》 2024年第4期274-291,共18页
Maintaining natural habitats is crucial for the preservation of insects and other species that indicate environmental changes. However, the Mpanga/Kipengere Game Reserve and its surrounding farmlands are facing distur... Maintaining natural habitats is crucial for the preservation of insects and other species that indicate environmental changes. However, the Mpanga/Kipengere Game Reserve and its surrounding farmlands are facing disturbance due to human activities, which is putting many wildlife species, particularly larger mammals, at risk. To determine the impact of human activities on butterfly species diversity and abundance in the reserve and its surrounding areas, we conducted a study from November 2021 to October 2023. We collected butterfly data using transect walks and baited traps in two habitat types. Our study yielded 2799 butterfly Individuals ranging in 124 species divided into five families habitat, season, and anthropogenic factors are significant environmental variables influencing species diversity and abundance of butterflies. Therefore, it’s important to protect habitat and dry-season water for the conservation of invertebrates such as butterflies. Our study findings provide essential information for ecological monitoring and future assessment of the Mpanga/Kipengere Game Reserve ecosystem health. 展开更多
关键词 Mpanga Kipengere Game reserve Species Diversity HABITAT Butterflies SEASON Human Activities
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The Effect of Uterine Artery Occlusion with Tourniquet on Ovarian Reserve during Open Myomectomy at a University Teaching Hospital in Southern Nigeria
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作者 William Amebeobari Mube Justina Omoikhefe Alegbeleye Ngozi Clare Orazulike 《Advances in Reproductive Sciences》 CAS 2024年第1期37-50,共14页
Background: The most common surgical treatment for symptomatic uterine fibroids, particularly in women with fertility concerns, is open myomectomy. Given the high vascularity of the uterus, haemorrhage during the proc... Background: The most common surgical treatment for symptomatic uterine fibroids, particularly in women with fertility concerns, is open myomectomy. Given the high vascularity of the uterus, haemorrhage during the procedure is a serious risk that is often mitigated with a uterine tourniquet. Aim and Objectives: To evaluate the effect of uterine artery occlusion with a tourniquet during open myomectomy on ovarian reserve using serial anti-Mullerian hormone (AMH) measurements. Materials and Methods: This was a prospective longitudinal study with a quasi-experimental design and a convenient sampling technique. The study enrolled 47 women who had abdominal myomectomy between September 1, 2021, and March 31, 2022, at the University of Port Harcourt Teaching Hospital. Blood samples were collected before anaesthesia was administered in theatre, on day two, and three months after open abdominal myomectomy for anti-Mullerian hormone assay. The data was collected using a semi-structured proforma, entered into an Excel spreadsheet, and analyzed using SPSS version 25.0 with a 95% confidence interval. Statistical significance level was set at 0.05. Results: The pre-surgery AMH mean value was 1.67 ± 1.44 ng/ml, while the values after using a uterine tourniquet at myomectomy on the second day and three months later were 1.22 ± 1.24 ng/ml and 1.59 ± 1.43 ng/ml, respectively. There was no statistically significant change in AMH levels, and there was no statistically significant relationship between blood loss and tourniquet time and AMH after open abdominal myomectomy. Conclusion: The use of a uterine tourniquet and blood loss during open myomectomy has no effect on ovarian reserve. 展开更多
关键词 Uterine Tourniquet Open Abdominal Myomectomy Ovarian reserve Anti-Mullerian Hormone NIGERIA
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Spatiotemporal Evolution of Ecological Quality in Alpine Freshwater Lake Nature Reserves in the Past 20 Years
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作者 Denghong HUANG Chenli LIAO +1 位作者 Zhenzhen ZHANG Jintong REN 《Meteorological and Environmental Research》 2024年第2期29-36,共8页
The Caohai Nature Reserve is one of the three major plateau freshwater lakes in China.Since the 1950s,human activities such as land reclamation and population relocation have greatly damaged Caohai.A rapid evaluation ... The Caohai Nature Reserve is one of the three major plateau freshwater lakes in China.Since the 1950s,human activities such as land reclamation and population relocation have greatly damaged Caohai.A rapid evaluation of the spatiotemporal evolution trend of the ecological quality of the Caohai Nature Reserve is significant for the maintenance and construction of the ecosystem in this area.The research is based on the Google Earth Engine(GEE)remote sensing cloud computing platform.Landsat TM/OLI images from May to October in five time periods:2000-2002,2004-2006,2009-2011,2014-2016,and 2019-2021 were obtained to reconstruct the optimal cloud image set by averaging the images in each time period.By constructing four ecological indicators:Greenness(NDVI),Wetness(Wet),Hotness(LST),and Dryness(NDBSI),and using Principal Component Analysis(PCA)method to obtain the Remote Sensing Ecological Index(RSEI)for the corresponding years,the spatiotemporal variation of ecological quality in the Caohai Nature Reserve over 20 years was analyzed.The results indicate:①the mean value of RSEI increased from 0.460 in 2000-2002 to 0.772 in 2019-2021,a 67.83%increase,indicating a significant improvement in the ecological quality of the reserve over the 20 years;②from the perspective of functional zoning of the Caohai Nature Reserve,the ecological quality of the core area showed a degrading trend,while the ecological quality of the buffer zone and experimental zone significantly improved;③with the implementation of ecological restoration projects,the ecological quality of the reserve gradually recovered and improved from 2014 to 2021.The trend of RSEI value changes is well correlated with human interventions,indicating that the PCA-based RSEI model can be effectively used for ecological quality assessment in lake areas. 展开更多
关键词 Ecological restoration Ecological quality Remote sensing ecological index Google Earth Engine Caohai Nature reserve
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Flora, Structure and Carbon Sequestration of Vegetation in the Southeast of the Mono Biosphere Reserve in Togo Amidst Environmental Challenges
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作者 Gbétey Kokouvi Akpamou Kossi Adjossou +3 位作者 Hodabalo Egbelou Komlanvi Katche Akoete Kossi Hounkpati Kouami Kokou 《Open Journal of Forestry》 2024年第2期155-181,共27页
In most Sub-Saharan African countries such as Togo, people’s heavy dependence on ecosystem services is a major factor in accelerating the degradation of natural resources, which are already suffering as a result of c... In most Sub-Saharan African countries such as Togo, people’s heavy dependence on ecosystem services is a major factor in accelerating the degradation of natural resources, which are already suffering as a result of climatic factors. This study was initiated to contribute to the sustainable and rational management of forest resources in the south-east of the Mono Biosphere Reserve in Togo. It specifically aims to identify and characterize the flora of the residual forest ecosystems within the reserve through their specific diversity, demographic structure, and carbon sequestration potential. The study was carried out in the forest ecosystems of Avévé. The methodology used was based on the analysis of phytosociological, forestry, ecological, and regeneration inventory data. Overall, the study revealed that the RBMT still has floristically viable habitats, despite the anthropogenic pressures it is subject to revealed a floristic diversity of 160 plant species divided into 52 families and 135 genera. The most represented families are Rubiaceae (29.09%), followed by Fabaceae (27.94%). The most represented species are Mitragyna inermis (Willd.) Kuntze (24.38%), Lecaniodiscus cupanioides Planch. Ex Benth (X) and Lonchocarpus sericeus (Poir.) Kunth (10.93%). The high presence of Mitragyna inermis observed in all the ecological groups identified makes it the characteristic species of the flooded marshy areas of southeast Togo and contributes to the resilience of the ecosystems and populations in the study area. The Shannon index for the formation groups varies between (3.03 and 5.16) bits. Pielou’s equitability varies between (0.43 and 0.63) bits. The overall average density is estimated at 210 stems/ha, with an average diameter of 25.57 ± 21.77 m and an average height of 7.93 ± 3.83 m. The adjustment of the diameter classes of the plant groups to the Weibull distribution gave an “inverted J” shape with coefficient values of less than 1 overall, reflecting the existence of multispecific or uneven-aged stands. Assessment of the horizontal and vertical structure shows a predominance of the shrub layer in all the groups identified. The carbon sequestration potential is 41.89 T/Ha. Despite ongoing anthropogenic pressures, the Mono Biosphere Reserve abounds in a relatively rich diversity of flora, the preservation of which is essential for the survival of biodiversity and even for the riparian population. The data provided by this study would form the basis for sustainable management planning of the forest islands in the biosphere reserve. 展开更多
关键词 BIODIVERSITY Demographic Structure Carbon Biosphere reserve Forest Patches TOGO
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Detection of Burned Areas through Spectral Indices Analysis of Sentinel-2A Satellite Images in the Abokouamékro Wildlife Reserve (Central, Côte D’Ivoire)
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作者 Bob Kouakou Kouadio Sié Ouattara +3 位作者 Alain Clément Jean-Marc Gala Bi Zaouri Jean-Luc Kouadio Kouassi Jean-Luc Edouard Kouakou N’guessan 《Open Journal of Applied Sciences》 2024年第1期205-222,共18页
In Côte d’Ivoire, the recurring and unregulated use of bushfires, which cause ecological damage, presents a pressing concern for the custodians of protected areas. This study aims to enhance our comprehension of... In Côte d’Ivoire, the recurring and unregulated use of bushfires, which cause ecological damage, presents a pressing concern for the custodians of protected areas. This study aims to enhance our comprehension of the dynamics of burnt areas within the Abokouamékro Wildlife Reserve (AWR) by employing the analysis of spectral indices derived from satellite imagery. The research methodology began with the calculation of mean indices and their corresponding spectral sub-indices, including NDVI, SAVI, NDWI, NDMI, BAI, NBR, TCW, TCG, and TCB, utilizing data from the Sentinel-2A satellite image dated January 17, 2022. Subsequently, a fuzzy classification model was applied to these various indices and sub-indices, guided by the degree of membership α, with the goal of effectively distinguishing between burned and unburned areas. Following the classification, the accuracies of the classified indices and sub-indices were validated using the coordinates of 100 data points collected within the AWR through GPS technology. The results revealed that the overall accuracy of all indices and sub-indices declines as the degree of membership α decreases from 1 to 0. Among the mean spectral indices, NDVI-mean, SAVI-mean, NDMI-mean exhibited the highest overall accuracies, achieving 97%, 95%, and 90%, respectively. These results closely mirrored those obtained by sub-indices using band 8 (NDVI-B8, SAVI-B8, and NDMI-B8), which yield respective overall accuracies of 93%, 92%, and 89%. At a degree of membership α = 1, the estimated burned areas for the most effective indices encompassed 2144.38 hectares for NDVI-mean, 1932.14 hectares for mean SAVI-mean, and 4947.13 hectares for mean NDMI-mean. A prospective approach involving the amalgamation of these three indices could have the potential to yield improved outcomes. This study could be a substantial contribution to the discrimination of bushfires in Côte d’Ivoire. 展开更多
关键词 Spectral Indices WILDFIRE Burned Areas Abokouamékro Wildlife reserve Côte D’Ivoire
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Assessment of hepatic functional reserve by cirrhosis grading and liver volume measurement using CT 被引量:21
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作者 Rong Tu Li-Ping Xia +1 位作者 An-Le Yu Ling Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第29期3956-3961,共6页
AIM: To explore a method for quantitative assessment of hepatic functional reserve by combining computed tomography (CT) volumetry with CT grading of liver cirrhosis before liver resection in patients with hepatoce... AIM: To explore a method for quantitative assessment of hepatic functional reserve by combining computed tomography (CT) volumetry with CT grading of liver cirrhosis before liver resection in patients with hepatocellular carcinoma. METHODS: CT images of 55 patients undergoing liver resection were studied prospectively. The degree of liver cirrhosis was referred as "CT grade" and the percentage of remnant liver volume (PRLV) [PRLV = predicted RLV/predicted total liver volume (PTLV) × 100%; PTLV (mL) = 121.75 + 16.49 × body mass (kg)] were calculated by adding slice by slice of CT liver images. The postoperative RLV, pathologic stages of liver fibrosis in non-tumor area and survival time in these cases were analyzed. RESULTS: There was a significant difference in survival time between the group with PRLV ≤ 50% and the group with PRLV 〉 50% (X^2= 4.988, P = 0.026), and between the group with CT grade 0/1 and the group with CT grade 2/3 (X^2= 5.429, P = 0.026). With combination of the both parameters, an oblique line was identified according to the distribution of 32 survivors versus 23 deceased subjects. The mortality rate above the line was 7.1% (1/14), and that below the line was 53.7% (22/41), indicating a significant difference between the two rates (X^2 = 9.281, P = 0.002, P 〈 0.05). CONCLUSION: PRLV and CT grades are significantly correlated with hepatic functional reserve. The predicted line using these two parameters is useful in candidates undergoing liver resection for judging hepatic functional reserve. 展开更多
关键词 Hepatic functional reserve Liver cirrhosis Computed tomography Hepatocellular carcinoma
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A Volumetric Model for Evaluating Tight Sandstone Gas Reserves in the Permian Sulige Gas Field,Ordos Basin,Central China 被引量:5
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作者 CUI Mingming FAN Aiping +3 位作者 WANG Zongxiu GAO Wanli LI Jinbu LI Yijun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第2期386-399,共14页
To accurately measure and evaluate reserves is critical for ensuring successful production of unconventional oil and gas. This work proposes a volumetric model to evaluate the tight sandstone gas reserves of the Permi... To accurately measure and evaluate reserves is critical for ensuring successful production of unconventional oil and gas. This work proposes a volumetric model to evaluate the tight sandstone gas reserves of the Permian Sulige gas field in the Ordos Basin. The reserves can be determined by four major parameters of reservoir cutoffs, net pay, gas-bearing area and compression factor Z, which are controlled by reservoir characteristics and sedimentation. Well logging, seismic analysis, core analysis and gas testing, as well as thin section identification and SEM analysis were used to analyze the pore evolution and pore-throat structure. The porosity and permeability cutoffs are determined by distribution function curve,empirical statistics and intersection plot. Net pay and gas-bearing area are determined based on the cutoffs, gas testing and sand body distribution, and the compression factor Z is obtained by gas component. The results demonstrate that the reservoir in the Sulige gas field is characterized by ultralow porosity and permeability, and the cutoffs of porosity and permeability are 5% and 0.15×10^(–3) μm^2, respectively. The net pay and gas-bearing area are mainly affected by the sedimentary facies, sand body types and distribution. The gas component is dominated by methane which accounts for more than 90%, and the compression factor Z of H_8(P_2h_8) and S_1(P_1s_1) are 0.98 and 0.985, respectively. The distributary channels stacked and overlapped, forming a wide and thick sand body with good developed intergranular pores and intercrystalline pores. The upper part of channel sand with good porosity and permeability can be sweet spot for gas exploration. The complete set of calculation systems proposed for tight gas reserve calculation has proved to be effective based on application and feedback. This model provides a new concept and consideration for reserve prediction and calculation in other areas. 展开更多
关键词 tight sandstone reservoir volumetric GAS reserve PERMIAN SULIGE GAS field ORDOS Basin
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hucMSC-derived exosomes protect ovarian reserve and restore ovarian function in cisplatin treated mice 被引量:4
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作者 Yue Xiao Yue Peng +3 位作者 Chi Zhang Wei Liu Kehan Wang Jing Li 《The Journal of Biomedical Research》 CAS CSCD 2023年第5期382-393,共12页
Anti-cancer therapy often causes premature ovarian insufficiency and infertility as the ovarian follicle reserve is extremely sensitive to chemotherapy drugs,such as cisplatin.Various fertility preservation methods ha... Anti-cancer therapy often causes premature ovarian insufficiency and infertility as the ovarian follicle reserve is extremely sensitive to chemotherapy drugs,such as cisplatin.Various fertility preservation methods have been explored for women,especially prepubertal girls undergoing radiotherapy and chemotherapy due to cancer.In recent years,mesenchymal stem cell-derived exosomes(MSC-exos)have been reported to play an important role in tissue repair and the treatment of various diseases.In the current study,we observed that human umbilical cord-derived MSC-exos(hucMSC-exos)after short-term culture improved follicular survival and development while receiving cisplatin treatment.Moreover,intravenous injection of hucMSC-exos improved ovarian function and ameliorated inflammatory environment within the ovary.The underlying mechanism of hucMSC-exos on fertility preservation was associated with the down-regulation of p53-related apoptosis and their anti-inflammatory function.Based on these findings,we propose that hucMSC-exos may be a potential approach to improve fertility in women diagnosed with cancer. 展开更多
关键词 ovarian function ovarian reserve CISPLATIN EXOSOMES apoptosis
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Clinical Application of Double Ovulation Stimulation in Patients with Diminished Ovarian Reserve and Asynchronous Follicular Development Undergoing Assisted Reproduction Technology 被引量:2
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作者 Yi-zhuo YANG Ming ZHANG +4 位作者 Sha MU Xin-meng Guo Hui WANG Zhe TANG Hong-mei PENG 《Current Medical Science》 SCIE CAS 2023年第2期304-312,共9页
Objective This study aimed to compare the clinical effects of double ovulation stimulation(DouStim)applied during the follicular and luteal phases with the antagonist protocol in patients with diminished ovarian reser... Objective This study aimed to compare the clinical effects of double ovulation stimulation(DouStim)applied during the follicular and luteal phases with the antagonist protocol in patients with diminished ovarian reserve(DOR)and asynchronous follicular development undergoing assisted reproductive technology(ART).Methods The clinical data of patients with DOR and asynchronous follicular development receiving ART from January 2020 to December 2021 were retrospectively analyzed.The patients were divided into two groups according to their ovulation stimulation protocol:DouStim group(n=30)and antagonist group(n=62).Assisted reproduction and clinical pregnancy outcomes were compared between the two groups.Results In the DouStim group,the number of oocytes retrieved,metaphase II(MII)oocytes,two-pronuclei(2PN),day 3(D3)embryos,D3 high-quality embryos as well as blastocyst formation,implantation,and human chorionic gonadotropin-positive rates were significantly greater than those in the antagonist group(all P<0.05).No significant differences were found in MII,fertilization,or continued pregnancy rates at the first frozen embryo transfer(FET),in-vitro fertilization(IVF)cancellation,or early medical abortion rates between the groups(all P>0.05).Except for the early medical abortion rate,the DouStim group generally had favorable outcomes.In the DouStim group,the dosage and duration of gonadotropin and the fertilization rate were significantly greater in the first ovulation stimulation induction than in the second ovulation stimulation induction(P<0.05).Conclusion The DouStim protocol efficiently and economically obtained more mature oocytes and high-quality embryos for patients with DOR and asynchronous follicular development. 展开更多
关键词 diminished ovarian reserve double ovulation stimulation follicular phase stimulation luteal phase stimulation
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Effects of land-use types and the exotic species,Hypochaeris radicata,on plant diversity in human-transformed landscapes of the biosphere reserve,Jeju Island,Korea 被引量:1
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作者 Deokjoo Son Bruce Waldman Uhram Song 《Plant Diversity》 SCIE CAS CSCD 2023年第6期685-693,共9页
Land-use and plant invasion influence biodiversity.Understanding the effects of land-use types and invasive plants on the ecosystem is crucial for better management and the development of strategic plans for increasin... Land-use and plant invasion influence biodiversity.Understanding the effects of land-use types and invasive plants on the ecosystem is crucial for better management and the development of strategic plans for increasing biodiversity in Jeju Island,Korea,a designated Biosphere Reserve by the United Nations Education,Scientific,and Cultural Organization.The effect of the most dominant invasive exotic species,Hypochaeris radicata,on the four land-use types of Jeju Island was investigated.Plant composition,soil characteristics,and plant diversity among four land-use types(cropland,green space,neglected land,and residential)were compared.Among the land-use types,croplands had the most diverse plant composition and the highest richness in exotic and native plant species.Croplands,such as tangerine orchards,which are widely distributed throughout Jeju Island,showed the highest plant diversity because of medium intensity disturbance caused by weed removal.The relative cover of H.radicata did not differ between land-use types.However,H.radicata invasion was negatively related with plant species richness,making this invasive species a threat to the biodiversity of native herbs present in land-use areas.H.radicata adapts to areas with a broad range of soil properties and a variety of land-use types.Therefore,it is crucial to monitor land-use types and patterns of plant invasion to guide the implementation of consistent management and conservation strategies for maintaining ecosystem integrity of the transformed habitat in Jeju Island. 展开更多
关键词 Biosphere reserve CROPLAND Invasive exotic plant Plant richness Intermediate disturbance hypothesis
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