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The Impacts and Causes of Land Fragmentation on Farm Productivity: Case Review of East African Countries
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作者 Joseph Mayindo Mayele Jacob B. Kolleh Joel Emmanuel Saburi 《Open Journal of Ecology》 2024年第5期455-482,共28页
This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of c... This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of complete collapse. Land fragmentation occurs when land gets converted for agriculture, industrialization, or urbanization, invaded by non-local plants, or enclosed for individual use and by subdividing farmlands into subsequent smaller units called parcels with varying average farm sizes. Fragmentation results from inappropriate agricultural development processes and ineffective land use planning that fails to recognize how farmland is used, and the importance of its interconnected areas. Insecurity of tenure and resource rights are key factors in making this possible. Land fragmentation is one of the key reasons why the ability of most resources in East Africa becomes scarcer, and those remaining become “privatized” by more powerful community members—keen to maintain their access to them. Such individualistic attitudes are new and disadvantage the poorest even further by affecting the traditional customary safety nets and agricultural outputs. Neither the government nor customary governance systems effectively protect resource access for the poorest. This review summary report identifies the key causes, measures, and implications, government interventions, and the common remedies to land fragmentation problems in the East African Countries of Kenya, Uganda, Rwanda, and Tanzania including neighboring Ethiopia, and the Sudan. The findings indicated from 2005 to 2015, the population kept increasing for all the named countries in East Africa with Rwanda and Uganda having a substantial increase in population density. The study review further explores the trend in the performance of agriculture by average farm sizes within the intervals of five years by highlighting their strong linkages and found that the average farm size has declined drastically, especially for Kenya. This can only mean that small farms kept becoming smaller and smaller and that there were more small-scale farmers. The results further depicted that the major and commonly cultivated food crops among the East African countries include maize, sorghum, rice, cassava, sweet potatoes, bananas, Irish potatoes, beans, peas, etc., with maize yields (Mt/ha) in 2003 for Uganda being the highest (1.79 Mt/ha) and the lowest in Rwanda (0.77 Mt/ha) respectively. Therefore, from the review results, recommendations are being made as to how the negative impacts of land fragmentation on agricultural productivity can be reduced or mitigated. One way is by community sensitization and awareness about the importance of land consolidation and its proposition on farm productivity. 展开更多
关键词 Land Fragmentation Land Consolidation Farm Productivity INDUSTRIALIZATION Impacts CAUSES Average Farm Size Population East Africa
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Determinants of Tobacco Cultivation and the Associated Impacts of Adoption in Hurungwe District, Zimbabwe
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作者 Spencer Sibanda Satoshi Tsuyuki 《Agricultural Sciences》 2024年第4期505-531,共27页
Tobacco is an essential cash crop in Zimbabwe and a strategic livelihood option for hundreds of thousands of rural households. However, the crop is linked to negative environmental, economic, and social impacts. The e... Tobacco is an essential cash crop in Zimbabwe and a strategic livelihood option for hundreds of thousands of rural households. However, the crop is linked to negative environmental, economic, and social impacts. The existing studies on tobacco cultivation in Zimbabwe present contradictory findings on the determinants and impacts of adoption, leaving unanswered questions about the crop’s sustainability impact in the country. This article investigates the determinants of smallholder farmers’ decisions to grow tobacco and the associated impacts of adoption. Random and purposive sampling were used to select 273 household surveys, including tobacco and non-tobacco smallholder farmers, and 56 expert interviews to answer the research questions. We employed regression models alongside expert interviews and document analysis to identify the determinants influencing the decision-making process of smallholder farmers in Zimbabwe regarding tobacco cultivation. Additionally, our investigation aimed to elucidate the perceived impacts associated with the adoption of this agricultural practice. The regression analysis indicated that the farmer’s age, education level, farming experience, family size, household income, and perceived high farm profitability are significant drivers of tobacco adoption. We also discovered divergent and convergent perceptions of the critical impacts of tobacco cultivation. The study highlights the need for proactive multi-stakeholder collaboration and sustainable financial arrangements to address the negative impacts of tobacco production. As the primary stakeholder responsible for regulating and promoting agricultural activities, the Zimbabwean government should provide meaningful financial support, increase access to credit, and ensure better market facilities for alternative crops to reduce the over-dependence on tobacco. 展开更多
关键词 Tobacco Cultivation Determinants of Adoption Sustainability Impacts Economic Livelihood Stakeholder Perceptions
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Evaluating the Impacts of Human Activities on Diversity, Abundance, and Distribution of Large Mammals in Nimule National Park, South Sudan
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作者 Abdallah Gordon Shazali Joseph Mayindo Mayele +1 位作者 Joel Emmanuel Saburi Jubara Nadlin 《Open Journal of Ecology》 2024年第5期483-507,共25页
Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habi... Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habitats, highlighting the need for conservation. This study aimed to assess the abundance and distribution of large mammals in different habitat types within Nimule National Park (NNP) and understand the impacts of human activities on them. Data on the abundance and distribution of large mammals and their respective habitat types were collected through line transect surveys. Human activity signs were observed and recorded along the transect lines. To estimate the impacts of human activities on the diversity, abundance, and distribution of large mammal species, as well as to identify any significant differences between them and their habitat types, the study utilized the Kruskal Wallis test, Polynomial multiple regressions, and diversity indices. The findings from the Shannon-Weiner and Simpson indices indicated that large mammal species were more diverse inside the park (H’ = 1.136;D = 0.570) compared to the buffer zone (H’ = 0.413;D = 0.171), with 85% (443 out of 510 samples) recorded within Nimule National Park. The species abundance showed a semi-balanced status (0.58). The diversity results among different habitat types revealed that large mammals were more diverse and highly distributed in both open woodlands (244) and dense woodlands (192), while riverine vegetation had the lowest diversity (8). Statistical tests demonstrated a highly significant difference at a 99% confidence interval (p-value = 0.01) between habitat types and identified species of large mammals. Additionally, the results highlighted the high abundance of Uganda kob (274), baboons (141), and warthog (57) across most habitat types, accounting for at least 75% of their distribution. The most prevalent human activities observed were cattle footprints (27%) and cattle dung (14%). Human footprints and tree cutting combined accounted for 9%, indicating the practice of livestock grazing, poaching, encroachment, and fuelwood collection by local communities. However, these activities did not appear to significantly impact the diversity, abundance, and distribution of large mammals in Nimule National Park. Therefore, it is crucial to foster shared responsibilities and engage relevant stakeholders in the management and conservation of large wildlife species. Regular community awareness programs should be implemented to cultivate a sense of ownership. Moreover, it is recommended that a comprehensive survey be conducted on the population status of all mammal species in Nimule National Park, including its surrounding Buffer Zone. Monitoring the impact of human activities on their behavior and habitats using satellite images should also be carried out at least every five to ten years. 展开更多
关键词 Diversity of Large Mammals Abundance and Distribution IMPACTS Biodiversity Conservation Human Activities Nimule National Park South Sudan
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Participatory Forest Management and Gender Inclusiveness within the Community Forest Management Groups of Bhutan
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作者 Norbu Zangmo Takuya Hiroshima +1 位作者 Spencer Sibanda Jigme Dorji 《Journal of Geoscience and Environment Protection》 2024年第4期12-30,共19页
Community forest management groups (CFMGs) in Bhutan exhibit participatory forest management practices that recognize the importance of community’s collective participation in the management of natural forest resourc... Community forest management groups (CFMGs) in Bhutan exhibit participatory forest management practices that recognize the importance of community’s collective participation in the management of natural forest resources. This approach involves the community in the stewardship of designated forest areas and resources to ensure sustainable livelihoods and realization of forest conservation objectives. The increase of CFMGs in the country has been successful. However, research on the extent of gender-inclusive participation in CFMGs is either insufficient or missing vis-à-vis the allocation of decision-making power. Therefore, this study analyzes the factors influencing gender participation in CFMGs and their integration into decision-making processes. Primary data were collected from 12 study sites spanning 4 regions, complemented by secondary data from the Forest Department. Regression models were used to identify factors significantly influencing CFMG member participation in decision-making. The empirical results of this study reveal that gender is a significant factor influencing participation in CFMG decision-making. The study concludes that there is insufficient participation of women members in decision-making processes. Therefore, consideration of gender should be included in the development phase of the CFMG policy in addition to promoting awareness of inequity between gender and the promotion of leadership roles for women in CFMGs. 展开更多
关键词 DECISION-MAKING Face-to-Face Interview Regression Analysis WOMEN
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The ALMA-QUARKS Survey.Ⅱ.The ACA 1.3 mm Continuum Source Catalog and the Assembly of Dense Gas in Massive Star-Forming Clumps
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作者 许峰玮 Ke Wang +30 位作者 Tie Liu Lei Zhu Guido Garay Xunchuan Liu Paul Goldsmith Qizhou Zhang Patricio Sanhueza Shengli Qin Jinhua He Mika Juvela Anandmayee Tej Hongli Liu Shanghuo Li Kaho Morii Siju Zhang Jianwen Zhou Amelia Stutz Neal JEvans Kee-Tae Kim Shengyuan Liu Diego Mardones Guangxing Li Leonardo Bronfman Ken’ichi Tatematsu Chang Won Lee Xing Lu Xiaofeng Mai Sihan Jiao James O.Chibueze Keyun Su Viktor L.Tóth 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期119-139,共21页
Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation... Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures”,is observing 139 massive starforming clumps at ALMA Band 6(λ~1.3 mm).This paper introduces the Atacama Compact Array(ACA)7 m data of the QUARKS survey,describing the ACA observations and data reduction.Combining multiwavelength data,we provide the first edition of QUARKS atlas,offering insights into the multiscale and multiphase interstellar medium in high-mass star formation.The ACA 1.3 mm catalog includes 207 continuum sources that are called ACA sources.Their gas kinetic temperatures are estimated using three formaldehyde transitions with a non-LTE radiation transfer model,and the mass and density are derived from a dust emission model.The ACA sources are massive(16–84 percentile values of 6–160 M_(⊙)),gravity-dominated(M∝R^(1.1))fragments within massive clumps,with supersonic turbulence(M>1)and embedded star-forming protoclusters.We find a linear correlation between the masses of the fragments and the massive clumps,with a ratio of 6%between the two.When considering fragments as representative of dense gas,the ratio indicates a dense gas fraction(DGF)of 6%,although with a wide scatter ranging from 1%to 10%.If we consider the QUARKS massive clumps to be what is observed at various scales,then the size-independent DGF indicates a self-similar fragmentation or collapsing mode in protocluster formation.With the ACA data over four orders of magnitude of luminosity-to-mass ratio(L/M),we find that the DGF increases significantly with L/M,which indicates clump evolutionary stage.We observed a limited fragmentation at the subclump scale,which can be explained by a dynamic global collapse process. 展开更多
关键词 stars:formation ISM:kinematics and dynamics ISM:clouds stars:protostars
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Decade Milestone Advancement of Defect-Engineered g-C_(3)N_(4) for Solar Catalytic Applications 被引量:1
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作者 Shaoqi Hou Xiaochun Gao +8 位作者 Xingyue Lv Yilin Zhao Xitao Yin Ying Liu Juan Fang Xingxing Yu Xiaoguang Ma Tianyi Ma Dawei Su 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期153-218,共66页
Over the past decade, graphitic carbon nitride(g-C_(3)N_(4)) has emerged as a universal photocatalyst toward various sustainable carbo-neutral technologies. Despite solar applications discrepancy, g-C_(3)N_(4) is stil... Over the past decade, graphitic carbon nitride(g-C_(3)N_(4)) has emerged as a universal photocatalyst toward various sustainable carbo-neutral technologies. Despite solar applications discrepancy, g-C_(3)N_(4) is still confronted with a general fatal issue of insufficient supply of thermodynamically active photocarriers due to its inferior solar harvesting ability and sluggish charge transfer dynamics. Fortunately, this could be significantly alleviated by the “all-in-one” defect engineering strategy, which enables a simultaneous amelioration of both textural uniqueness and intrinsic electronic band structures. To this end, we have summarized an unprecedently comprehensive discussion on defect controls including the vacancy/non-metallic dopant creation with optimized electronic band structure and electronic density, metallic doping with ultraactive coordinated environment(M–N_(x), M–C_(2)N_(2), M–O bonding), functional group grafting with optimized band structure, and promoted crystallinity with extended conjugation π system with weakened interlayered van der Waals interaction. Among them, the defect states induced by various defect types such as N vacancy, P/S/halogen dopants, and cyano group in boosting solar harvesting and accelerating photocarrier transfer have also been emphasized. More importantly, the shallow defect traps identified by femtosecond transient absorption spectra(fs-TAS) have also been highlighted. It is believed that this review would pave the way for future readers with a unique insight into a more precise defective g-C_(3)N_(4) “customization”, motivating more profound thinking and flourishing research outputs on g-C_(3)N_(4)-based photocatalysis. 展开更多
关键词 Defect engineering g-C_(3)N_(4) Electronic band structures Photocarrier transfer kinetics Defect states
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Molecular dynamics study of thermal conductivities of cubic diamond,lonsdaleite,and nanotwinned diamond via machine-learned potential
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作者 熊佳豪 戚梓俊 +6 位作者 梁康 孙祥 孙展鹏 汪启军 陈黎玮 吴改 沈威 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第12期594-601,共8页
Diamond is a wide-bandgap semiconductor with a variety of crystal configurations,and has the potential applications in the field of high-frequency,radiation-hardened,and high-power devices.There are several important ... Diamond is a wide-bandgap semiconductor with a variety of crystal configurations,and has the potential applications in the field of high-frequency,radiation-hardened,and high-power devices.There are several important polytypes of diamonds,such as cubic diamond,lonsdaleite,and nanotwinned diamond(NTD).The thermal conductivities of semiconductors in high-power devices at different temperatures should be calculated.However,there has been no reports about thermal conductivities of cubic diamond and its polytypes both efficiently and accurately based on molecular dynamics(MD).Here,using interatomic potential of neural networks can provide obvious advantages.For example,comparing with the use of density functional theory(DFT),the calculation time is reduced,while maintaining high accuracy in predicting the thermal conductivities of the above-mentioned three diamond polytypes.Based on the neuroevolution potential(NEP),the thermal conductivities of cubic diamond,lonsdaleite,and NTD at 300 K are respectively 2507.3 W·m^(-1)·K^(-1),1557.2 W·m^(-1)·K^(-1),and 985.6 W·m^(-1)·K^(-1),which are higher than the calculation results based on Tersoff-1989 potential(1508 W·m^(-1)·K^(-1),1178 W·m^(-1)·K^(-1),and 794 W·m^(-1)·K^(-1),respectively).The thermal conductivities of cubic diamond and lonsdaleite,obtained by using the NEP,are closer to the experimental data or DFT data than those from Tersoff-potential.The molecular dynamics simulations are performed by using NEP to calculate the phonon dispersions,in order to explain the possible reasons for discrepancies among the cubic diamond,lonsdaleite,and NTD.In this work,we propose a scheme to predict the thermal conductivity of cubic diamond,lonsdaleite,and NTD precisely and efficiently,and explain the differences in thermal conductivity among cubic diamond,lonsdaleite,and NTD. 展开更多
关键词 DIAMOND neuroevolution potential molecular dynamics thermal conductivity phonon transport
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A combination of tides and nontidal variations in ocean bottom pressure may generate interannual slip fluctuations in the transition zone along a subduction plate interface
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作者 Yoshiyuki Tanaka Hiromu Sakaue +1 位作者 Masayuki Kano Suguru Yabe 《Geodesy and Geodynamics》 CSCD 2023年第1期43-51,共9页
The tidal triggering of earthquakes has been studied for many years.The discovery of slow earthquakes in the early 2000s,including slow slip,has urged scientists to investigate the tidal responses of these earthquakes... The tidal triggering of earthquakes has been studied for many years.The discovery of slow earthquakes in the early 2000s,including slow slip,has urged scientists to investigate the tidal responses of these earthquakes due to their sensitivity to weak stress perturbations.Previous studies have shown that slow earthquakes correlate with diurnal and semidiurnal tides and seasonal variations in surface loads more clearly than ordinary earthquakes.However,little is known about long-term responses to external stresses.In this paper,based on a widely accepted frictional law for faults,a mechanism is proposed by which nontidal variations in ocean bottom pressure,when combined with tides,pro mote the occurrence of slow earthquakes.Because slow earthquakes accompany a slip on the plate interface,this mechanism allows one to estimate slip modulations.A one-degree-of-freedom slip model is constructed and applied to Ise Bay in the Tonankai region of southwestern Japan,where large-scale ocean mass redistributions have occurred.The model calculated with parameters determined from the observation of tectonic tremors is quantitatively consistent with the slip during 1997-2013 inferred from GNSS data,suggesting that the decrease in the sea-level change in approximately 2006 could cause the accele ration of a slip observed after that.This result implies that the decreases in sea level in approximately 1996 and 2014 could also cause subsequent slip accelerations.These three slip acceleration periods temporally coincide with the increases in background seismicity in a shallower portion of the plate interface.These changes in seismicity are common to shallow earthquakes in the Tokai area,and a similar model can reproduce them.Further studies are expected to reveal causality between shallow earthquakes and long-term slip fluctuations based on modeling that considers changes in the frictional property along the plate interface. 展开更多
关键词 TIDES Ocean bottom pressure Slow earthquake SEISMICITY Kuroshio current
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Long-term survival of the Sister Mary Joseph nodule originating from breast cancer:A case report
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作者 Koji Kanayama Maki Tanioka +2 位作者 Yoshitsugu Hattori Takuya Iida Mutsumi Okazaki 《World Journal of Clinical Cases》 SCIE 2023年第34期8205-8211,共7页
BACKGROUND A Sister Mary Joseph nodule(SMJN)is an uncommon cutaneous metastasis found in the umbilicus,indicating an advanced malignancy.SMJNs typically originate from intra-abdominal sources,rarely from breast cancer... BACKGROUND A Sister Mary Joseph nodule(SMJN)is an uncommon cutaneous metastasis found in the umbilicus,indicating an advanced malignancy.SMJNs typically originate from intra-abdominal sources,rarely from breast cancer.Diagnosis suggests a poor prognosis with a median survival of approximately 8 mo after detection.Managing patients with SMJNs is challenging,as most receive limited palliative care only.The optimal strategy for long-term survival of these patients remains unclear.CASE SUMMARY A 58-year-old female,previously diagnosed with right breast cancer 17 years ago and underwent breast-conserving surgery,adjuvant radiotherapy,and endocrine therapy,presented with a 2-cm umbilical nodule.Thirteen years previously,metastases were detected in the right supraclavicular,infraclavicular,hilar,and mediastinal lymph nodes.An umbilical nodule emerged four years before the date of presentation,confirmed as a skin metastasis of primary breast cancer upon excisional biopsy.Despite initial removal,the nodule recurred and grew,leading to her referral to our hospital.The patient underwent extensive excision of the umbilical tumor and immediate abdominal wall reconstruction.Endocrine therapy was continued postoperatively.Five years later,no local recurrence was observed,and the patient continued to work full-time,achieving over 9 years of survival following SMJN diagnosis.CONCLUSION This case study aimed to identify the optimal strategy for achieving extended survival outcomes in patients with SMJN through comprehensive treatment.We presented a case of the longest survival in a patient after undergoing a multidisciplinary treatment regimen.Our findings underscore the significance of adopting a multimodal treatment approach comprising timely and wide excision along with adjunctive therapy.This approach can control the disease,prolong survival,and improve the quality of life in patients with SMJN. 展开更多
关键词 Sister Mary Joseph nodule Breast cancer Cutaneous metastasis Long-term survival Abdominal wall reconstruction Case report
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Effectiveness of antibiotic prophylaxis for acute esophageal variceal bleeding in patients with band ligation: A large observational study 被引量:1
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作者 Chikamasa Ichita Sayuri Shimizu +4 位作者 Tadahiro Goto Uojima Haruki Naoya Itoh Masao Iwagami Akiko Sasaki 《World Journal of Gastroenterology》 SCIE CAS 2024年第3期238-251,共14页
BACKGROUND Esophageal variceal bleeding is a severe complication associated with liver cirrhosis and typically necessitates endoscopic hemostasis.The current standard treatment is endoscopic variceal ligation(EVL),and... BACKGROUND Esophageal variceal bleeding is a severe complication associated with liver cirrhosis and typically necessitates endoscopic hemostasis.The current standard treatment is endoscopic variceal ligation(EVL),and Western guidelines recom-mend antibiotic prophylaxis following hemostasis.However,given the impro-vements in prognosis for variceal bleeding due to advancements in the management of bleeding and treatments of liver cirrhosis and the global concerns regarding the emergence of multidrug-resistant bacteria,there is a need to reassess the use of routine antibiotic prophylaxis after hemostasis.AIM To evaluate the effectiveness of antibiotic prophylaxis in patients treated for EVL.METHODS We conducted a 13-year observational study using the Tokushukai medical database across 46 hospitals.Patients were divided into the prophylaxis group(received antibiotics on admission or the next day)and the non-prophylaxis group(did not receive antibiotics within one day of admission).The primary outcome was composed of 6-wk mortality,4-wk rebleeding,and 4-wk spontaneous bacterial peritonitis(SBP).The secondary outcomes were each individual result and in-hospital mortality.A logistic regression with inverse probability of treatment weighting was used.A subgroup analysis was conducted based on the Child-Pugh classification to determine its influence on the primary outcome measures,while sensitivity analyses for antibiotic type and duration were also performed.RESULTS Among 980 patients,790 were included(prophylaxis:232,non-prophylaxis:558).Most patients were males under the age of 65 years with a median Child-Pugh score of 8.The composite primary outcomes occurred in 11.2%of patients in the prophylaxis group and 9.5%in the non-prophylaxis group.No significant differences in outcomes were observed between the groups(adjusted odds ratio,1.11;95%confidence interval,0.61-1.99;P=0.74).Individual outcomes such as 6-wk mortality,4-wk rebleeding,4-wk onset of SBP,and in-hospital mortality were not significantly different between the groups.The primary outcome did not differ between the Child-Pugh subgroups.Similar results were observed in the sensitivity analyses.CONCLUSION No significant benefit to antibiotic prophylaxis for esophageal variceal bleeding treated with EVL was detected in this study.Global reassessment of routine antibiotic prophylaxis is imperative. 展开更多
关键词 Esophageal varices Endoscopic hemostasis Antibiotic prophylaxis Liver cirrhosis Inverse probability of treatment weighting
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Nutrient-regulated dynamics of chondroprogenitors in the postnatal murine growth plate
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作者 Takeshi Oichi Joe Kodama +9 位作者 Kimberly Wilson Hongying Tian Yuka Imamura Kawasawa Yu Usami Yasushi Oshima Taku Saito Sakae Tanaka Masahiro Iwamoto Satoru Otsuru Motomi Enomoto-Iwamoto 《Bone Research》 SCIE CAS CSCD 2023年第2期340-353,共14页
Longitudinal bone growth relies on endochondral ossification in the cartilaginous growth plate,where chondrocytes accumulate and synthesize the matrix scaffold that is replaced by bone.The chondroprogenitors in the re... Longitudinal bone growth relies on endochondral ossification in the cartilaginous growth plate,where chondrocytes accumulate and synthesize the matrix scaffold that is replaced by bone.The chondroprogenitors in the resting zone maintain the continuous turnover of chondrocytes in the growth plate.Malnutrition is a leading cause of growth retardation in children;however,after recovery from nutrient deprivation,bone growth is accelerated beyond the normal rate,a phenomenon termed catch-up growth.Although nutritional status is a known regulator of long bone growth,it is largely unknown whether and how chondroprogenitor cells respond to deviations in nutrient availability.Here,using fate-mapping analysis in Axin2CreERT2 mice,we showed that dietary restriction increased the number of Axin2+chondroprogenitors in the resting zone and simultaneously inhibited their differentiation.Once nutrient deficiency was resolved,the accumulated chondroprogenitor cells immediately restarted differentiation and formed chondrocyte columns,contributing to accelerated growth.Furthermore,we showed that nutrient deprivation reduced the level of phosphorylated Akt in the resting zone and that exogenous IGF-1 restored the phosphorylated Akt level and stimulated differentiation of the pooled chondroprogenitors,decreasing their numbers.Our study of Axin2CreERT2 revealed that nutrient availability regulates the balance between accumulation and differentiation of chondroprogenitors in the growth plate and further demonstrated that IGF-1 partially mediates this regulation by promoting the committed differentiation of chondroprogenitor cells. 展开更多
关键词 PROGENITOR PLATE MAINTAIN
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Assessing Forest Cover Distribution, Species Diversity, and Richness of the Buffer Zone for Strategic Forest Management Planning for Nimule National Park, South Sudan
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作者 Joseph Mayindo Mayele Augustine Lokule Bongo 《Open Journal of Ecology》 2023年第11期836-864,共29页
Natural forest ecosystems play an essential role in the conservation of biodiversity of many plants and animals by providing them with habitat and suitable environments. Studies have shown that biodiversity-protected ... Natural forest ecosystems play an essential role in the conservation of biodiversity of many plants and animals by providing them with habitat and suitable environments. Studies have shown that biodiversity-protected areas reduce the loss and degradation of natural habitats to various wild species of plants. This study examined the forest resources in five subzones by conducting tree/shrub species inventory to be able to develop an effective forest management plan for the Buffer Zone Forest Reserve for the sustainable conservation of flora and fauna of Nimule National Park. This is with the view to identify the main tree and shrub species;assess the composition, distribution, and abundance of various tree/shrub species;to determine the species diversity as well as the richness of these areas in terms of growth and performance where DBH and heights of trees/shrubs in the circular sample plots were measured. The results revealed the overall mean DBH and H of 13.83 cm and 6.61 m respectively. The highest number of trees was obtained in subzone B followed by D, while the least were found in subzone A. The overall mean tree/shrub density was 0.83 tons/ha. The mean total basal area and volume per hectare were 3252.74 m<sup>2</sup>/ha and 46,540.82 m<sup>3</sup>/ha respectively. The overall species abundance and distribution indicate Combretum spp, Cedrella spp., Grewia mollis, Acacia Sieberiana, Ziziphus abysinica, and Acacia seyal were the most dominant species, with over 12 species richness at the deposition side of the River Nile, 13 species at the western side of the Nile, the Administration site shows only 7 species, the lowland of Mt. Gordon show over 14 different species, whereas over 10 species were found on the top of Mt. Gordon. The overall mean diversity indices and evenness of H’, D, and E depicted 2.507, 0.871, and 0.840 respectively. These results yielded are relatively moderate. Therefore, conservation efforts are very necessary to improve and maintain the quality of vegetation cover. 展开更多
关键词 Species Diversity Species Abundance Species Richness Buffer Zone Nimule National Park South Sudan
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Determining the Effects of Selected Organic Fertilizer on Growth and Yields of Tomato (Lycopersicon esculentum: Var. Rio Grande Tomatoes) in Mundri West County, Western Equatoria State, South Sudan
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作者 Joseph Mayindo Mayele Felix Rufas Abu 《Agricultural Sciences》 2023年第9期1343-1374,共32页
Worldwide, the demand for agro-organic foods that are healthy, nutritious, and environmentally friendly is increasing dramatically across all nations among consumers. Tomatoes being one of the dietary requirements in ... Worldwide, the demand for agro-organic foods that are healthy, nutritious, and environmentally friendly is increasing dramatically across all nations among consumers. Tomatoes being one of the dietary requirements in almost every meal is not exceptional and its availability in the market all year round is very important to farmers as well as consumers because it is highly demanded as a vegetable par excellence;which is either eaten raw in salads, cooked or processed into liquid ingredients. This study investigates the impact of chicken, goat, and cow manure treatments on tomato plant growth response to height, leaf length, and width, as well as fruit yield. The experimental field trials were conducted over two planting seasons in Mundri West County. It followed a Complete Randomized Design (CRD) approach, consisting of four blocks. Each block contained three treatments replicated four times and a control group. The data of measured parameters from all 16 plots were subjected to one-way Analysis of Variance (ANOVA) using the Gen Stat 14th Edition software. The findings indicate significant differences (P < 0.05) among all the different organic manure applications on tomato plant growth parameters compared to the control group. Chicken manure resulted in the tallest tomato plants (30.1 and 37.9 cm), longest leaves (9.9 and 10.4 cm), and widest leaves (2.1 and 2.5 cm) in both seasons respectively. The study showed plots treated with chicken manure had a highly significant impact (P < 0.05) on the prevalence of aphids (1.0) and white flies (1.4) with the lowest value compared to those with cow and goat manure applied. Additionally, chicken manure led to the highest yields (39.30 and 49.49 tons/ha) in both seasons. Based on these findings, it can be concluded that using chicken manure effectively improves the performance of Rio Grande Tomatoes, and thus, farmers are encouraged to utilize chicken manure to maximize their tomato yields. 展开更多
关键词 Tomato Yield Organic Fertilizers/Manures Tomato Pests Mundri West South Sudan
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Experimental investigation on effective aerosol scavenging using different spray configurations with pre-injection of water mist for Fukushima Daiichi decommissioning
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作者 Rui-Cong Xu Avadhesh Kumar Sharma +2 位作者 Erdal Ozdemir Shuichiro Miwa Shunichi Suzuki 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期154-172,共19页
During the decommissioning of the Fukushima Daiichi nuclear power plant,it is important to consider the retrieval of resolidified debris both in air and underwater configurations.For the subsequent retrieval of debris... During the decommissioning of the Fukushima Daiichi nuclear power plant,it is important to consider the retrieval of resolidified debris both in air and underwater configurations.For the subsequent retrieval of debris from the reactor building,the resolidified debris must be cut into smaller pieces using various cutting methods.During the cutting process,aerosol particles are expected to be generated at the submicron scale.It has been noted that such aerosols sizing within the Greenfield gap(0.1-1μm)are difficult to remove effectively using traditional spraying methods.Therefore,to improve the aerosol removal efficiency of the spray system,a new aerosol agglomeration method was recently proposed,which involves injecting water mist to enlarge the sizes of the aerosol particles before removing them using water sprays.In this study,a series of experiments were performed to clarify the proper spray configurations for effective aerosol scavenging and to improve the performance of the water mist.The experimental results showed that the spray flow rate and droplet characteristics are important factors for the aerosol-scavenging efficiency and performance of the water mist.The results obtained from this study will be helpful for the optimization of the spray system design for effective aerosol scavenging during the decommissioning of the Fukushima Daiichi plant. 展开更多
关键词 Fukushima Daiichi decommissioning Aerosol scavenging Multiphase flow Spray system Aerosol-mist agglomeration
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Investigation of Inside-Out Tracking Methods for Six Degrees of Freedom Pose Estimation of a Smartphone in Augmented Reality
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作者 Chanho Park Takefumi Ogawa 《Computers, Materials & Continua》 SCIE EI 2024年第5期3047-3065,共19页
Six degrees of freedom(6DoF)input interfaces are essential formanipulating virtual objects through translation or rotation in three-dimensional(3D)space.A traditional outside-in tracking controller requires the instal... Six degrees of freedom(6DoF)input interfaces are essential formanipulating virtual objects through translation or rotation in three-dimensional(3D)space.A traditional outside-in tracking controller requires the installation of expensive hardware in advance.While inside-out tracking controllers have been proposed,they often suffer from limitations such as interaction limited to the tracking range of the sensor(e.g.,a sensor on the head-mounted display(HMD))or the need for pose value modification to function as an input interface(e.g.,a sensor on the controller).This study investigates 6DoF pose estimation methods without restricting the tracking range,using a smartphone as a controller in augmented reality(AR)environments.Our approach involves proposing methods for estimating the initial pose of the controller and correcting the pose using an inside-out tracking approach.In addition,seven pose estimation algorithms were presented as candidates depending on the tracking range of the device sensor,the tracking method(e.g.,marker recognition,visual-inertial odometry(VIO)),and whether modification of the initial pose is necessary.Through two experiments(discrete and continuous data),the performance of the algorithms was evaluated.The results demonstrate enhanced final pose accuracy achieved by correcting the initial pose.Furthermore,the importance of selecting the tracking algorithm based on the tracking range of the devices and the actual input value of the 3D interaction was emphasized. 展开更多
关键词 SMARTPHONE inside-out tracking 6DoF pose 3D interaction augmented reality
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Optimized operation scheme of flash-memory-based neural network online training with ultra-high endurance
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作者 Yang Feng Zhaohui Sun +6 位作者 Yueran Qi Xuepeng Zhan Junyu Zhang Jing Liu Masaharu Kobayashi Jixuan Wu Jiezhi Chen 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期33-37,共5页
With the rapid development of machine learning,the demand for high-efficient computing becomes more and more urgent.To break the bottleneck of the traditional Von Neumann architecture,computing-in-memory(CIM)has attra... With the rapid development of machine learning,the demand for high-efficient computing becomes more and more urgent.To break the bottleneck of the traditional Von Neumann architecture,computing-in-memory(CIM)has attracted increasing attention in recent years.In this work,to provide a feasible CIM solution for the large-scale neural networks(NN)requiring continuous weight updating in online training,a flash-based computing-in-memory with high endurance(10^(9) cycles)and ultrafast programming speed is investigated.On the one hand,the proposed programming scheme of channel hot electron injection(CHEI)and hot hole injection(HHI)demonstrate high linearity,symmetric potentiation,and a depression process,which help to improve the training speed and accuracy.On the other hand,the low-damage programming scheme and memory window(MW)optimizations can suppress cell degradation effectively with improved computing accuracy.Even after 109 cycles,the leakage current(I_(off))of cells remains sub-10pA,ensuring the large-scale computing ability of memory.Further characterizations are done on read disturb to demonstrate its robust reliabilities.By processing CIFAR-10 tasks,it is evident that~90%accuracy can be achieved after 109 cycles in both ResNet50 and VGG16 NN.Our results suggest that flash-based CIM has great potential to overcome the limitations of traditional Von Neumann architectures and enable high-performance NN online training,which pave the way for further development of artificial intelligence(AI)accelerators. 展开更多
关键词 NOR flash memory computing-in-memory ENDURANCE neural network online training
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Operation and Consideration of a Pipe Corrosion Inspection System Based on Human-in-the-Loop Machine Learning
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作者 Toshihiro Shimbo Yousuke Okada Hitoshi Matsubara 《Journal of Mechanics Engineering and Automation》 2023年第5期127-135,共9页
The aim of this study is to improve the efficiency of external corrosion inspection of pipes in chemical plants.Currently,the preferred method involves manual inspection of images of corroded pipes;however,this places... The aim of this study is to improve the efficiency of external corrosion inspection of pipes in chemical plants.Currently,the preferred method involves manual inspection of images of corroded pipes;however,this places significant workload on human experts owing to the large number of required images.Furthermore,visual assessment of corrosion levels is prone to subjective errors.To address these issues,we developed an AI(artificial intelligence)-based corrosion-diagnosis system(AI corrosion-diagnosis system)and implemented it in a factory.The proposed system architecture was based on HITL(human-in-the-loop)ML(machine learning)[1].To overcome the difficulty of developing a highly accurate ML model during the PoC(proof-of-concept)stage,the system relies on cooperation between humans and the ML model,utilizing human expertise during operation.For instance,if the accuracy of the ML model was initially 60%during the development stage,a cooperative approach would be adopted during the operational stage,with humans supplementing the remaining 40%accuracy.The implemented system’s ML model achieved a recall rate of approximately 70%.The system’s implementation not only contributed to the efficiency of operations by supporting diagnosis through the ML model but also facilitated the transition to systematic data management,resulting in an overall workload reduction of approximately 50%.The operation based on HITL was demonstrated to be a crucial element for achieving efficient system operation through the collaboration of humans and ML models,even when the initial accuracy of the ML model was low.Future efforts will focus on improving the detection of corrosion at elevated locations by considering using video cameras to capture pipe images.The goal is to reduce the workload for inspectors and enhance the quality of inspections by identifying corrosion locations using ML models. 展开更多
关键词 HITL ML collaboration between human and machine learning diagnostic imaging smart maintenance.
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The neutrophil–osteogenic cell axis promotes bone destruction in periodontitis
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作者 Yutaro Ando Masayuki Tsukasaki +12 位作者 Nam Cong-Nhat Huynh Shizao Zang Minglu Yan Ryunosuke Muro Kazutaka Nakamura Masatsugu Komagamine Noriko Komatsu Kazuo Okamoto Kenta Nakano Tadashi Okamura Akira Yamaguchi Kazuyuki Ishihara Hiroshi Takayanagi 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期154-162,共9页
The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction b... The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction by inducing receptor activator of nuclear factor-κB ligand (RANKL) expression in osteogenic cells such as osteoblasts and periodontal ligament cells. However, the detailed mechanism underlying immune–bone cell interactions in periodontitis is not fully understood. Here, we performed single-cell RNAsequencing analysis on mouse periodontal lesions and showed that neutrophil–osteogenic cell crosstalk is involved in periodontitis-induced bone loss. The periodontal lesions displayed marked infiltration of neutrophils, and in silico analyses suggested that the neutrophils interacted with osteogenic cells through cytokine production. Among the cytokines expressed in the periodontal neutrophils, oncostatin M (OSM) potently induced RANKL expression in the primary osteoblasts, and deletion of the OSM receptor in osteogenic cells significantly ameliorated periodontitis-induced bone loss. Epigenomic data analyses identified the OSM-regulated RANKL enhancer region in osteogenic cells, and mice lacking this enhancer showed decreased periodontal bone loss while maintaining physiological bone metabolism. These findings shed light on the role of neutrophils in bone regulation during bacterial infection, highlighting the novel mechanism underlying osteoimmune crosstalk. 展开更多
关键词 period NEUTROPHIL DESTRUCTION
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Projected impacts of climate change and anthropogenic effects on habitat distribution of endangered Javan Hawk-Eagle in Indonesia
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作者 Syartinilia Aryo Adhi Condro Satoshi Tsuyuki 《Geography and Sustainability》 CSCD 2024年第2期241-250,共10页
Changing climate will jeopardize biodiversity,particularly the geographic distribution of endemic species.One such species is the Javan Hawk-Eagle(JHE,Nisaetus bartelsi),a charismatic raptor found only on Java Island,... Changing climate will jeopardize biodiversity,particularly the geographic distribution of endemic species.One such species is the Javan Hawk-Eagle(JHE,Nisaetus bartelsi),a charismatic raptor found only on Java Island,Indonesia.Thus,it is crucial to develop an appropriate conservation strategy to preserve the species.Ecological niche modeling is considered a valuable tool for designing conservation plans for the JHE.We provide an ecological niche modeling approach and transfer its model to future climate scenarios for the JHE.We utilize various machine learning algorithms under sustainability and business-as-usual(BAU)scenarios for 2050.Additionally,we investigate the conservation vulnerability of the JHE,capturing multifaceted pressures on the species from climate dissimilarities and human disturbance variables.Our study reveals that the ensemble model performs exceptionally well,with temperature emerging as the most critical factor affecting the JHE distribution.This finding indicates that climate change will have a significant impact on the JHE species.Our results suggest that the JHE distribution will likely decrease by 28.41%and 40.16%from the current JHE distribution under sustainability and BAU scenarios,respectively.Furthermore,our study reveals high-potential refugia for future JHE,covering 7,596 km^(2)(61%)under the sustainability scenario and only 4,403 km^(2)(35%)under the BAU scenario.Therefore,effective management and planning,including habitat restoration,refugia preservation,habitat connectivity,and local community inclusivity,should be well-managed to achieve JHE conservation targets. 展开更多
关键词 Climate change Ecological niche Ensemble model REFUGIA Javan Hawk-Eagle
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Transcriptional reprogramming during human osteoclast differentiation identifies regulators of osteoclast activity
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作者 Morten S.Hansen Kaja Madsen +6 位作者 Maria Price Kent Søe Yasunori Omata Mario M.Zaiss Caroline M.Gorvin Morten Frost Alexander Rauch 《Bone Research》 SCIE CAS CSCD 2024年第1期180-198,共19页
Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutic... Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutics are needed,understanding the genetic regulation of human osteoclastogenesis could help identify potential treatment targets.This study aimed to provide an overview of transcriptional reprogramming during human osteoclast differentiation.Osteoclasts were differentiated from CD14+monocytes from eight female donors.RNA sequencing during differentiation revealed 8980 differentially expressed genes grouped into eight temporal patterns conserved across donors.These patterns revealed distinct molecular functions associated with postmenopausal osteoporosis susceptibility genes based on RNA from iliac crest biopsies and bone mineral density SNPs.Network analyses revealed mutual dependencies between temporal expression patterns and provided insight into subtype-specific transcriptional networks.The donor-specific expression patterns revealed genes at the monocyte stage,such as filamin B(FLNB)and oxidized low-density lipoprotein receptor 1(OLR1,encoding LOX-1),that are predictive of the resorptive activity of mature osteoclasts.The expression of differentially expressed G-protein coupled receptors was strong during osteoclast differentiation,and these receptors are associated with bone mineral density SNPs,suggesting that they play a pivotal role in osteoclast differentiation and activity.The regulatory effects of three differentially expressed G-protein coupled receptors were exemplified by in vitro pharmacological modulation of complement 5 A receptor 1(C5AR1),somatostatin receptor 2(SSTR2),and free fatty acid receptor 4(FFAR4/GPR120).Activating C5AR1 enhanced osteoclast formation,while activating SSTR2 decreased the resorptive activity of mature osteoclasts,and activating FFAR4 decreased both the number and resorptive activity of mature osteoclasts.In conclusion,we report the occurrence of transcriptional reprogramming during human osteoclast differentiation and identified SSTR2 and FFAR4 as antiresorptive G-protein coupled receptors and FLNB and LOX-1 as potential molecular markers of osteoclast activity.These data can help future investigations identify molecular regulators of osteoclast differentiation and activity and provide the basis for novel antiosteoporotic targets. 展开更多
关键词 OSTEOCLAST PROGRAMMING identif
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