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Automated Actuarial Data Analytics-Based Inflation Adjusted Frequency Severity Loss Reserving Model
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作者 Brighton Mahohoho 《Open Journal of Statistics》 2024年第3期341-393,共53页
In this paper, the Automated Actuarial Loss Reserving Model is developed and extended using machine learning. The traditional actuarial reserving techniques are no longer compatible with the increase in technological ... In this paper, the Automated Actuarial Loss Reserving Model is developed and extended using machine learning. The traditional actuarial reserving techniques are no longer compatible with the increase in technological advancement currently at hand. As a result, the development of the alternative Artificial Intelligence Based Automated Actuarial Loss Reserving Methodology which captures diverse risk profiles for various policyholders through augmenting the Micro Finance services, Auto Insurance Services and Both Services lines of business on the same platform through the computation of the Comprehensive Automated Actuarial Loss Reserves (CAALR) has been implemented in this paper. The introduction of the four further types of actuarial loss reserves to those existing in the actuarial literature seems to significantly reduce lapse rates, reduce the reinsurance costs as well as expenses and outgo. As a matter of consequence, this helps to bring together a combination of new and existing policyholders in the insurance company. The frequency severity models have been extended in this paper using ten machine learning algorithms which ultimately leads to the derivation of the proposed machine learning-based actuarial loss reserving model which remarkably performed well when compared to the traditional chain ladder actuarial reserving method using simulated data. 展开更多
关键词 Automated Actuarial Loss Reserves Artificial Intelligence Micro Finance Loss reserving Auto Insurance Loss reserving Both Services Loss reserving
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The Actuarial Data Intelligent Based Artificial Neural Network (ANN) Automobile Insurance Inflation Adjusted Frequency Severity Loss Reserving Model
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作者 Brighton Mahohoho 《Open Journal of Statistics》 2024年第5期634-665,共32页
This study proposes a novel approach for estimating automobile insurance loss reserves utilizing Artificial Neural Network (ANN) techniques integrated with actuarial data intelligence. The model aims to address the ch... This study proposes a novel approach for estimating automobile insurance loss reserves utilizing Artificial Neural Network (ANN) techniques integrated with actuarial data intelligence. The model aims to address the challenges of accurately predicting insurance claim frequencies, severities, and overall loss reserves while accounting for inflation adjustments. Through comprehensive data analysis and model development, this research explores the effectiveness of ANN methodologies in capturing complex nonlinear relationships within insurance data. The study leverages a data set comprising automobile insurance policyholder information, claim history, and economic indicators to train and validate the ANN-based reserving model. Key aspects of the methodology include data preprocessing techniques such as one-hot encoding and scaling, followed by the construction of frequency, severity, and overall loss reserving models using ANN architectures. Moreover, the model incorporates inflation adjustment factors to ensure the accurate estimation of future loss reserves in real terms. Results from the study demonstrate the superior predictive performance of the ANN-based reserving model compared to traditional actuarial methods, with substantial improvements in accuracy and robustness. Furthermore, the model’s ability to adapt to changing market conditions and regulatory requirements, such as IFRS17, highlights its practical relevance in the insurance industry. The findings of this research contribute to the advancement of actuarial science and provide valuable insights for insurance companies seeking more accurate and efficient loss reserving techniques. The proposed ANN-based approach offers a promising avenue for enhancing risk management practices and optimizing financial decision-making processes in the automobile insurance sector. 展开更多
关键词 Artificial Neural Network Actuarial Loss reserving Machine Learning Intelligent Model
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Statistical Modeling of Gate Capacitance Variations Induced by Random Dopants in Nanometer MOSFETs Reserving Correlations
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作者 吕伟锋 王光义 +1 位作者 林弥 孙玲玲 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第10期159-161,共3页
We consider intrinsic gate capacitance variations due to random dopants in the nanometer metal oxide semi- conductor field effect transistor (MOSFET) channel. The variations of total gate capacitance and gate transc... We consider intrinsic gate capacitance variations due to random dopants in the nanometer metal oxide semi- conductor field effect transistor (MOSFET) channel. The variations of total gate capacitance and gate transcapacitances are investigated and the strong correlations between the trans-capacitance variations are discovered. A simple statistical model is proposed for accurately capturing total gate capacitance variability based on the correlations. The model fits very well with the Monte Carlo simulations and the average errors are -0.033% for n-type metal-oxide semiconductor and -0.012% for p-type metal-oxide semiconductor, respectively. Our simulation studies also indicate that, owing to these correlations, the total gate capacitance variability will not dominate in gate capacitance variations. 展开更多
关键词 MOSFET Statistical Modeling of Gate Capacitance Variations Induced by Random Dopants in Nanometer MOSFETs reserving Correlations
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Molecular Environment of Reserving Information (M.E.R.I. Technology)
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作者 Iman Moradi Vahid Nahvi +1 位作者 Rasul Salehi Mohaddeseh Behjati 《International Journal of Intelligence Science》 2012年第4期103-105,共3页
The idea of application from DNA information organization for providing the next generation super-computers has been proposed by lessons learned from nature. Thus, molecular environment of reserving information was co... The idea of application from DNA information organization for providing the next generation super-computers has been proposed by lessons learned from nature. Thus, molecular environment of reserving information was considered as succeeding generation of a mother-board project containing some subcategories with various applications. MERI, constructed based on the binary coding system using DNA synthesizer machine, enables retrievable reading of molecular structures using DNA sequencer machine. It has high capacity for reservation of information about 1.212 × 1011 Kb/cm2 with long-term stability. It can be used in various fields of science and technology regarding its high capacity, small size and safety measures. 展开更多
关键词 INFORMATION reserving DNA INFORMATION MOLECULAR ENVIRONMENT NUCLEOTIDES DNA MACROMOLECULES
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CLINICAL SIGNIFICANCE OF "TREATING VITALITY" AND "RESERVING VITALITY"
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作者 魏立新 《World Journal of Acupuncture-Moxibustion》 2006年第1期42-44,53,共4页
“Treating vitality”and“ reserving vitality”are very important manipulations during acupuncture treatment of diseases.“Treating vitality” comprises adjusting and treating both the acupuncture doctor's and the pa... “Treating vitality”and“ reserving vitality”are very important manipulations during acupuncture treatment of diseases.“Treating vitality” comprises adjusting and treating both the acupuncture doctor's and the patient's vitality; while “reserving vitality” demands the acupuncture doctor carefully to experience the sensations of 'excess' or 'deficiency' under the needle, wait for the arrival of qi, observe the patient's responses, and then perform reducing or reinforcing needling manipulations in accordance with the state of excess-or deficiency-syndrome. “Treating vitality”and “reserving vitality” impenetrate the whole process of acupuncture treatment all along. Through years' clinical practice, the author of the present paper discusses the functions of the two aspects in every stage of acupuncture treatment, including before acupuncture, during needle insertion, during retention and withdrawal of the needle. The purpose of this paper is to explain the clinical significance of treating and reserving vitality and arouse many acupuncture doctors'attention. 展开更多
关键词 Acupuncture therapy Treating vitality reserving vitality
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THE FACTORS AND TREATMENT OF LOCAL RECURRENCE AFTER RADICAL RESECTION RESERVING THE ANUS IN THE PATIENTS WITH RECTAL CANCER
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作者 单吉贤 陈峻青 +1 位作者 张文范 齐春莲 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第4期73-76,共4页
Of seventy-one patients with rectal cancer after radical resection retaining the anus, 15 developed local recurrence with a recurrence rate of 21.1%. Local recurrence was correlated with improper safety margin from th... Of seventy-one patients with rectal cancer after radical resection retaining the anus, 15 developed local recurrence with a recurrence rate of 21.1%. Local recurrence was correlated with improper safety margin from the lower edge of cancer to the anal end. There was statistical significant difference between 3 cm or more and 2 cm or less. The local recurrence was also related to the pathologic stage, histologic differentiation and implant of free cancer cells. It is suggested that the surgical indication of saving the anus be strict and without stretching, the safety margin from the lower edge of cancer to the anal end should not be less than 2 cm in early rectal cancer and not less than 4 cm in advanced lesions. During the operation, no touching tumor technique, thorough rinsing of the peritoneal cavity and pre- or post-operative radiotherapy are important for prevention of local recurrence. Early local recurrent rectal cancer can be detected by periodic examinations. 展开更多
关键词 THE FACTORS AND TREATMENT OF LOCAL RECURRENCE AFTER RADICAL RESECTION reserving THE ANUS IN THE PATIENTS WITH RECTAL CANCER
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Touristic urbanization and greening of coastal dune fields:A long-term assessment of a temperate sandy barrier of Argentina 被引量:1
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作者 GARZO Pedro Andrés DADON JoséRoberto ISLA Federico Ignacio 《Journal of Geographical Sciences》 2025年第1期206-230,共25页
Dune barrier systems represent highly sought-after coastal landscapes for tourism and urban development around the world.However,a century ago,they were considered hazardous environments due to their great dynamic nat... Dune barrier systems represent highly sought-after coastal landscapes for tourism and urban development around the world.However,a century ago,they were considered hazardous environments due to their great dynamic nature.As a result,stabilization practices were considered necessary.The systematic introduction of fast-growing exotic trees helped stabilize the sand,making it easier for tourism urbanization to take place,but also leading to erosion processes.This paper aims to assess long-term changes in vegetation cover over a large temperate barrier in Argentina.This complex region includes urban resorts,afforestation zones,and protected areas.A GIS-based geospatial analysis was conducted using a large satellite database(>350 images),and the future evolution of the vegetation was modeled.The results revealed two primary spatiotemporal patterns associated with a gradual expansion of vegetation cover,accompanied by a concurrent reduction in sandy areas.In 1986,the dune area comprised 75%more surface than vegetation,whereas in 2021,it represented 60%less than vegetation.Furthermore,the 2050 scenario suggests a potential 40%reduction of dunes in certain areas.It is necessary to enhance management actions aimed at maintaining dune mobility and ensuring local and regional sediment balance.Long-term management strategies must focus on restoring native plant communities and controlling invasive species,and avoiding new dune fixation initiatives based on the introduction of exotic species. 展开更多
关键词 nature reserves AFFORESTATION sediment balance dune management NDVI
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Drivers of Groundwater Storage Dynamics in China's Ordos Mining Region:Integrating Natural and Anthropogenic Influences 被引量:1
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作者 LIU Zhiqiang ZHANG Shengwei +5 位作者 FAN Wenjie HUANG Lei ZHANG Xiaojing LUO Meng YANG Lin ZHANG Zhiqi 《Chinese Geographical Science》 2025年第4期693-706,I0001,I0002,共16页
Clarifying the mechanisms through which coal mining affects groundwater storage(GWS)variations is crucial for water resource conservation and sustainable development.The Ordos Mining Region in China,a key energy base ... Clarifying the mechanisms through which coal mining affects groundwater storage(GWS)variations is crucial for water resource conservation and sustainable development.The Ordos Mining Region in China,a key energy base in China with significant strategic importance,has undergone intensive coal mining activities that have substantially disrupted regional groundwater circulation.This study integrated data from the Gravity Recovery and Climate Experiment Satellite(GRACE)and Famine Early Warning Systems Network(FEWS NET)Land Data Assimilation System(FLDAS)models,combined with weighted downscaling methodology and water balance principles,to reconstruct high-resolution(0.01°)terrestrial water storage(TWS)and GWS changes in the Ordos Mining Region,China from April 2002 to December 2021.The accuracy of GWS variations were validated through pumping test measurements.Subsequently,Geodetector analysis was implemented to quantify the contributions of natural and anthropogenic factors to groundwater storage dynamics.Key findings include:1)TWS in the study area showed a fluctuating but overall decreasing trend,with a total reduction of 8901.11 mm during study period.The most significant annual decrease occurred in 2021,reaching 1696.77 mm.2)GWS exhibited an accelerated decline,with an average annual change rate of 44.35 mm/yr,totaling a decrease of 887.05 mm.The lowest annual groundwater storage level was recorded in 2020,reaching 185.69 mm.3)Precipitation(PRE)contributed the most to GWS variation(q=0.52),followed by coal mining water consumption(MWS)(q=0.41).The interaction between PRE and MWS exhibited a nonlinear enhancement effect on GWS changes(0.54).The synergistic effect of natural hydrological factors has a great influence on the change of GWS,but coal mining water consumption will continue to reduce GWS.These findings provide critical references for the management and regulation of groundwater resource in mining regions. 展开更多
关键词 groundwater reserves groundwater storage(GWS) terrestrial water storage(TWS) Gravity Recovery and Climate Experiment Satellite(GRACE) Famine Early Warning Systems Network(FEWS NET)Land Data Assimilation System(FLDAS) Ordos Mining Region China
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GGN repeat length of the androgen receptor gene is associated with antral follicle count in Chinese women undergoing controlled ovarian stimulation
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作者 LIU Xinyan FAN Qi +5 位作者 DENG Mingfen XU Yan GUO Jing CAO Ping ZHOU Canquan XU Yanwen 《南方医科大学学报》 北大核心 2025年第2期213-222,共10页
Objective To evaluate the association of GGN repeat polymorphism of androgen receptor(AR)with ovarian reserve and ovarian response in controlled ovarian stimulation(COS).Methods This genetic association study was cond... Objective To evaluate the association of GGN repeat polymorphism of androgen receptor(AR)with ovarian reserve and ovarian response in controlled ovarian stimulation(COS).Methods This genetic association study was conducted among a total of 361 women aged≤40 years with basal FSH≤12 U/L undergoing the GnRH-agonist long protocol for COS in a university affiliated IVF center.GGN repeat in the AR gene was analyzed with Sanger sequencing.The primary endpoint was the number of antral follicle counts(AFCs),and the secondary endpoints were stimulation days,total dose of gonadotropin(Gn)used,total number of retrieved oocytes,ovarian sensitivity index,and follicular output rate.Results The GGN repeat in exon 1 of the AR gene ranged from 13 to 24,and the median repeat length was 22.Based on the genotypes(S for GGN repeats<22,L for GGN repeats≥22),the patients were divided into 3 groups:SS,SL,and LL.Generalized regression analysis indicated that the number of AFCs in group SS was significantly lower than those in group SL(adjusted β=1.8,95%CI:0.2-3.4,P=0.024)and group LL(adjusted β=1.5,95%CI:0.2-2.7,P=0.021).No significant difference was observed in the number of AFCs between group SL and group LL(P>0.05).Generalized regression analysis indicated no significant differences in ovarian stimulation parameters among the 3 groups,either before or after adjusting for confounding factors(P>0.05).Conclusion GGN repeat length on the AR gene is associated with AFC but not with ovarian response in Chinese women,indicating that AR gene polymorphisms may affect ovarian reserve. 展开更多
关键词 androgen receptor GGN polymorphism ovarian reserve ovarian stimulation
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Noradrenergic excitation of astrocytes supports cognitive reserve
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作者 Robert Zorec Alexei Verkhratsky 《Neural Regeneration Research》 2026年第4期1546-1547,共2页
The concept of the brain cognitive reserve is derived from the well-acknowledged notion that the degree of brain damage does not always match the severity of clinical symptoms and neurological/cognitive outcomes.It ha... The concept of the brain cognitive reserve is derived from the well-acknowledged notion that the degree of brain damage does not always match the severity of clinical symptoms and neurological/cognitive outcomes.It has been suggested that the size of the brain(brain reserve) and the extent of neural connections acquired through life(neural reserve) set a threshold beyond which noticeable impairments occur.In contrast,cognitive reserve refers to the brain's ability to adapt and reo rganize stru cturally and functionally to resist damage and maintain function,including neural reserve and brain maintenance,resilience,and compensation(Verkhratsky and Zorec,2024). 展开更多
关键词 ASTROCYTES brain reserve cognitive reserve clinical symptoms noradrenergic excitation neural reserve neural connections brain cognitive reserve
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Stochastic loss reserving using individual information model with over-dispersed Poisson
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作者 Zhigao Wang Xianyi Wu Chunjuan Qiu 《Statistical Theory and Related Fields》 2022年第2期114-128,共15页
For stochastic loss reserving,we propose an individual information model(IIM)which accom-modates not only individual/micro data consisting of incurring times,reporting developments,settlement developments as well as p... For stochastic loss reserving,we propose an individual information model(IIM)which accom-modates not only individual/micro data consisting of incurring times,reporting developments,settlement developments as well as payments of individual claims but also heterogeneity among policies.We give over-dispersed Poisson assumption about the moments of reporting developments and payments of every individual claims.Model estimation is conducted under quasi-likelihood theory.Analytic expressions are derived for the expectation and variance of outstanding liabilities,given historical observations.We utilise conditional mean square error of prediction(MSEP)to measure the accuracy of loss reserving and also theoretically prove that when risk portfolio size is large enough,IIM shows a higher prediction accuracy than individ-ual/micro data model(IDM)in predicting the outstanding liabilities,if the heterogeneity indeed influences claims developments and otherwise IIM is asymptotically equivalent to IDM.Some simulations are conducted to investigate the conditional MSEPs for IIM and IDM.A real data analysis is performed basing on real observations in health insurance. 展开更多
关键词 Risk management loss reserving individual information model over-dispersed Poisson QUASI-LIKELIHOOD MSEP
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NATURAL WONDERS IN CHINA AND AFRICA
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《ChinAfrica》 2025年第8期62-63,共2页
CHINA Gaoligongshan National Natural Reserve Rising to over 4,000 metres above sea level in western Yunnan Province,Gaoligong Mountain forms part of the southern Hengduan Mountain Range and is renowned for its rich bi... CHINA Gaoligongshan National Natural Reserve Rising to over 4,000 metres above sea level in western Yunnan Province,Gaoligong Mountain forms part of the southern Hengduan Mountain Range and is renowned for its rich biodiversity and vibrant cultural landscape.Encompassing a vast protected area across the Tengchong and Baoshan regions,the Gaoligongshan National Natural Reserve is a secluded ecological treasure trove.In April 2000,the reserve joined the UNESCO World Network of Biosphere Reserves. 展开更多
关键词 natural reserve Hengduan Mountains BIODIVERSITY Western Yunnan Province Gaoligongshan gaoligongshan national natural reserve UNESCO World Network Biosphere Reserves ecological treasure trove
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NATURE’S GIFT
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《ChinAfrica》 2025年第10期62-63,共2页
Established in 1958,Xishuangbanna National Nature Reserve is one of China’s first protected areas.Covering about 2,435 square km,it is the country’s largest tropical primeval forest and one of the world’s most biol... Established in 1958,Xishuangbanna National Nature Reserve is one of China’s first protected areas.Covering about 2,435 square km,it is the country’s largest tropical primeval forest and one of the world’s most biologically diverse regions.In 1993,it became part of the UNESCO World Biosphere Reserve Network,reflecting its global ecological significance. 展开更多
关键词 tropical primeval forest national nature reserve biological diversity nature reserve UNESCO World Biosphere Reserve Network
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Performance assessment of computed tomographic angiography fractional flow reserve using deep learning:SMART trial summary
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作者 Wei ZHANG You-Bing YIN +9 位作者 Zhi-Qiang WANG Ying-Xin ZHAO Dong-Mei SHI Yong-He GUO Zhi-Ming ZHOU Zhi-Jian WANG Shi-Wei YANG De-An JIA Li-Xia YANG Yu-Jie ZHOU 《Journal of Geriatric Cardiology》 2025年第9期793-801,共9页
Background Non-invasive computed tomography angiography(CTA)-based fractional flow reserve(CT-FFR)could become a gatekeeper to invasive coronary angiography.Deep learning(DL)-based CT-FFR has shown promise when compar... Background Non-invasive computed tomography angiography(CTA)-based fractional flow reserve(CT-FFR)could become a gatekeeper to invasive coronary angiography.Deep learning(DL)-based CT-FFR has shown promise when compared to invasive FFR.To evaluate the performance of a DL-based CT-FFR technique,DeepVessel FFR(DVFFR).Methods This retrospective study was designed for iScheMia Assessment based on a Retrospective,single-center Trial of CTFFR(SMART).Patients suspected of stable coronary artery disease(CAD)and undergoing both CTA and invasive FFR examinations were consecutively selected from the Beijing Anzhen Hospital between January 1,2016 to December 30,2018.FFR obtained during invasive coronary angiography was used as the reference standard.DVFFR was calculated blindly using a DL-based CTFFR approach that utilized the complete tree structure of the coronary arteries.Results Three hundred and thirty nine patients(60.5±10.0 years and 209 men)and 414 vessels with direct invasive FFR were included in the analysis.At per-vessel level,sensitivity,specificity,accuracy,positive predictive value(PPV)and negative predictive value(NPV)of DVFFR were 94.7%,88.6%,90.8%,82.7%,and 96.7%,respectively.The area under the receiver operating characteristics curve(AUC)was 0.95 for DVFFR and 0.56 for CTA-based assessment with a significant difference(P<0.0001).At patient level,sensitivity,specificity,accuracy,PPV and NPV of DVFFR were 93.8%,88.0%,90.3%,83.0%,and 95.8%,respectively.The computation for DVFFR was fast with the average time of 22.5±1.9 s.Conclusions The results demonstrate that DVFFR was able to evaluate lesion hemodynamic significance accurately and effectively with improved diagnostic performance over CTA alone.Coronary artery disease(CAD)is a critical disease in which coronary artery luminal narrowing may result in myocardial ischemia.Early and effective assessment of myocardial ischemia is essential for optimal treatment planning so as to improve the quality of life and reduce medical costs. 展开更多
关键词 Coronary Artery Disease invasive coronary angiographydeep Diagnostic Performance ischemia assessment fractional flow reserve ct ffr could Deep Learning Ischemia Assessment Fractional Flow Reserve
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NATURE’S GIFT NATURAL WONDERS IN CHINA AND AFRICA
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《ChinAfrica》 2025年第11期62-63,共2页
CHINA Tarim Populus Euphratica National Nature Reserve Located along the northern edge of the Taklimakan Desert in Xinjiang,the Tarim Populus Euphratica National Nature Reserve lies in the middle reaches of the Tarim ... CHINA Tarim Populus Euphratica National Nature Reserve Located along the northern edge of the Taklimakan Desert in Xinjiang,the Tarim Populus Euphratica National Nature Reserve lies in the middle reaches of the Tarim River-the longest inland river in China-within Bayingolin Mongol Autonomous Prefecture.Established in 1983 and upgraded to a national reserve in 2006,it covers an area of about 395,420 hectares,including a core,bu!er,and experimental zone.The reserve features alluvial plains and desert terrain,with elevations ranging from 800 to 940 metres.The landscape consists of river floodplains,ancient riverbeds,and oasis margins,forming a remarkable ecological mosaic shaped by the Tarim River and its tributaries.The region experiences a typical temperate continental desert climate-dry,hot,and windy with scarce rainfall. 展开更多
关键词 inland river taklimakan desert tarim populus euphratica national nature reserve nature reserve Taklimakan Desert Tarim River alluvial plains Tarim Populus euphratica
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Composition Analysis of Lycophytes and Ferns in Yunzhongshan Nature Reserve, Fujian Province
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作者 Jinquan SHEN Minyong LU +4 位作者 Baohua WU Lingming LIN Jinhuo HE Ying FENG Yinbing XIE 《Plant Diseases and Pests》 2025年第2期34-37,共4页
[Objectives]To analyze the composition of lycophytes and ferns in Yunzhongshan Nature Reserve,Fujian Province.[Methods]This study examined the composition of lycophytes and ferns in Yunzhongshan Nature Reserve through... [Objectives]To analyze the composition of lycophytes and ferns in Yunzhongshan Nature Reserve,Fujian Province.[Methods]This study examined the composition of lycophytes and ferns in Yunzhongshan Nature Reserve through field investigations and specimen identification,supplemented by a review of relevant literature.[Results]A total of 84 species of lycophytes and ferns were identified,encompassing 55 genera and 29 families.This included 14 species of lycophytes distributed across 8 genera and 3 families,as well as 70 species of ferns belonging to 47 genera and 26 families.Polypodiaceae and Selaginella were the dominant family and genus,respectively,while oligospecific families and monotypic genera were significant components of lycophytes and ferns in the region.The distribution types of these families were primarily cosmopolitan and tropical.The Germline differentiation degree(SD)was 3.34,and the proportion of rare or endangered species among lycophytes and ferns was 8.33%.[Conclusions]Yunzhongshan Nature Reserve possesses a diverse array of lycophyte and fern species.This study offers valuable scientific insights that can inform efforts related to the conservation of biodiversity,resource utilization and development,species introduction,and system evolution of lycophytes and ferns within the reserve. 展开更多
关键词 NATURE RESERVE LYCOPHYTES FERNS COMPOSITION
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Deer Haven
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《ChinAfrica》 2025年第8期4-5,共2页
A milu deer crosses a river in Dafeng,Jiangsu Province,on 2 July.The city is home to the world’s largest milu deer nature reserve,covering 78,000 hectares and hosting the largest wild population of the species globally.
关键词 DEER milu deer nature reserve wild population dafeng jiangsu province RIVER
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Subcutaneous delivery of icariin via a gelatin methacryloyl(GelMA)hydrogel sustained-release system improves ovarian function in reproductively aged mice
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作者 Jia-Lian Mao Xiang-Yi Wu +12 位作者 Ling-Xi Li Ning Li Ya-Xuan Wang Zhi-Wei Jiang Chuan-Ming Liu Hui-Dan Zhang Ji-Dong Zhou Yang Zhang Li Chen Gui-Jun Yan Hai-Xiang Sun Yi-Fan Li Li-Jun Ding 《Zoological Research》 2025年第4期863-876,共14页
Ovarian aging is characterized by a progressive decline in oocyte quality and quantity with age.Icariin(ICA),a flavonoid compound derived from Epimedium species,has demonstrated potential as an agent for ovarian resto... Ovarian aging is characterized by a progressive decline in oocyte quality and quantity with age.Icariin(ICA),a flavonoid compound derived from Epimedium species,has demonstrated potential as an agent for ovarian restoration.In this study,a subcutaneous implantation system using gelatin methacryloyl(GelMA)hydrogel embedded with ICA was developed to restore ovarian function in aged female mice.Mice were assigned to receive subcutaneous implantation of GelMA alone(GelMA group),GelMA containing ICA(GelMA/ICA group),or a sham operation.Ovarian morphology,serum hormone levels,follicle counts across developmental stages,and reproductive outcomes were evaluated.In vitro fertilization(IVF)and embryo culture assays were performed to assess oocyte developmental potential,while a 10 day natural mating trial was conducted to determine fertility restoration.RNA sequencing(RNA-seq)and RT-qPCR were performed to elucidate the underlying molecular mechanisms.Results showed that GelMA/ICA treatment significantly increased ovarian index(0.19±0.01 vs.0.13±0.01,P<0.0001)and follicle numbers at all developmental stages,including primordial(383.33±151.65 vs.107.14±32.26,P<0.0001),primary(203.33±83.22 vs.91.43±27.04,P=0.003),and secondary follicles(154.17±52.00 vs.59.28±20.50,P=0.029)compared to the sham controls.Hormonal analyses revealed a significant reduction in serum follicle-stimulating hormone(FSH,11.97±3.53 vs.53.10±17.89 ng/mL,P=0.0008),accompanied by elevated anti-Müllerian hormone(AMH,22.97±2.26 vs.5.54±1.56 ng/mL,P<0.0001)and estradiol(E2,315.30±37.62 vs.168.5±14.78 pg/mL,P<0.0001).Oocyte yield and developmental potential improved significantly,as reflected by the increased number of superovulated MII oocytes(17.83±5.15 vs.4.83±4.79,P=0.0002),and higher proportions of two-cell(85.90%±6.16%vs.50.00%±10.00%,P=0.0009),four-cell(81.67%±9.76%vs.50.00%±10.00%,P=0.0061),and blastocyst stage embryos(64.25%±10.55%vs.23.33%±15.28%,P=0.0067).Live birth numbers were significantly increased following GelMA/ICA treatment(6.90±3.21 vs.1.72±2.05,P=0.0001).Transcriptomic analysis revealed up-regulation of genes associated with cytoskeletal organization(Vil1,Tubb3),lipid storage(Soat2,Plin4),oocyte maturation(Oosp2),and cytokine secretion(Cxcl12).Collectively,these findings suggest that GelMA/ICA hydrogels effectively reverse key hallmarks of ovarian aging and restore reproductive function in aged mice,offering a promising platform for fertility preservation and a novel therapeutic for future investigations into ovarian aging. 展开更多
关键词 Ovarian aging ICARIIN Subcutaneous implantation GelMA Ovarian reserve
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Sustainable Tourism Development in the Ždiar Highland Municipality in the Transition Zone of the Tatra Biosphere Reserve(Slovakia)
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作者 Veronika Piscová Zuzana Pucherová +4 位作者 Regína Mišovičová Gabriel Bugár Juraj Hreško Katarína Vitálišová Andrej Sedlák 《Journal of Environmental & Earth Sciences》 2025年第5期381-400,共20页
The Goral municipality of Ždiar(a Conservation Reserve of Folk Architecture since 1977)is one of the most attractive areas in Slovakia under the growing influence of the developing tourism.Since 1949 it has been part ... The Goral municipality of Ždiar(a Conservation Reserve of Folk Architecture since 1977)is one of the most attractive areas in Slovakia under the growing influence of the developing tourism.Since 1949 it has been part of the protection zone of the Tatra National Park and since 1993 it has been part of the transition zone of the Tatra Biosphere Reserve.In recent years,tourism has taken a major role in the transition zone of this biosphere reserve.In the presented contribution,we therefore evaluate the impact of developing tourism in the cadastral area of the municipality ofŽdiar between 1950 and 2022.We rely primarily on available statistical data from various sources and on the analysis of the historical and contemporary landscape structure.During this period,almost 50%of the area has changed land cover.The activities that have significantly changed the landscape include afforestation,deforestation,agrointensification,deurbanisation(naturalisation),urbanisation(anthropisation):tourism development and construction of a water reservoir.Tourism has become the main driver of the economy here and opens up opportunities especially for local inhabitants.However,the lack of completed tourism infrastructure is a drawback.We recommend the establishment of the Coordinating Council of the Tatra Biosphere Reserve and permanent employees at the National Park Administration. 展开更多
关键词 DEVELOPMENT TOURISM Ždiar Land Cover Changes Tatra Biosphere Reserve Slovakia
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Study on the Impact of Single-port Laparoscopic Surgery Based on Minimally Invasive Instrument Engineering Optimization on Biomarkers of Ovarian Reserve Function
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作者 WU Wen-yan CHEN Fu-chun +2 位作者 ZHANG Ling-jie WANG Jin-yong LIN Shu-ping 《Chinese Journal of Biomedical Engineering(English Edition)》 2025年第2期78-85,共8页
Objective:To investigate the quantitative influence of engineering parameters(diameter,bending angle)of minimally invasive surgical instruments and single-port laparoscopic surgery on biomarkers of ovarian reserve fun... Objective:To investigate the quantitative influence of engineering parameters(diameter,bending angle)of minimally invasive surgical instruments and single-port laparoscopic surgery on biomarkers of ovarian reserve function,and establish a multi-parameter coupled mathematical prediction model,providing a theoretical basis for precision instrument design and operation optimization.Methods:A total of 45 reproductive-age patients undergoing single-port laparoscopic ovarian cystectomy were selected.Through orthogonal experimental design,the instrument diameter(3/5/8 mm)and bending angle(30°/60°/90°)were divided into 9 groups,with5 cases in each group.Changes in serum AMH(anti-müllerian hormone),FSH(follicle-stimulating hormone),INHB(inhibin B)and ultrasonic AFC(antral follicle count)indexes were measured before surgery and on the 2nd to 3rd day of the first menstrual period after surgery.Enhanced CT images and laparoscopic images of ovarian force distribution were obtained.Finite element analysis(FEA)of the single-port instrument-ovarian tissue model was performed using ABAQUS software to calculate stress distribution in the ovarian cortex.Oscillatory shear experiments were used to determine the characteristics of viscoelastic property changes in the linear viscoelastic range of ovarian tissue.Results:The rate of decrease in AMH was lower in the 3 mm diameter-30°angle group(P<0.05);the peak Von Mises stress in the D3-θ30 group was lower than that in the other groups(P<0.05);the optimal parameter combination was a diameter of 3.13 mm and an angle of 21.72°,with the model calculating an AMH attenuation of 20%.Ovarian tissue changed with the frequency of the oscillatory shear test.In the low-frequency region(<1 Hz):G'>G''(elasticity-dominated);in the high-frequency region(>5 Hz):G''>G'(viscosity-dominated);the crossover point was at 5 Hz,where G'=G''=5 kPa.Before ovarian dissection:G'was relatively high and G''was relatively low,with elasticity dominating.During dissection:G'decreased and G''increased,with instrument stress causing damage.After dissection:G'further decreased and G''continued to rise,resulting in irreversible damage to the ovarian stroma.Conclusion:The engineering parameters of minimally invasive instruments significantly affect the ovarian reserve function index AMH and the peak Von Mises stress of the ovary through mechanical stress transmission.Using an instrument with a diameter of 3.13 mm and a bending angle of 21.72°can more effectively reduce the impact of single-port laparoscopic surgery on AMH decline. 展开更多
关键词 single-port laparoscopic surgery OVARY ovarian reserve function AMH finite element
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