期刊文献+
共找到111篇文章
< 1 2 6 >
每页显示 20 50 100
Migration and Pathological Journeys: A Case Report of 5 Patients at the National Hospital in Niamey
1
作者 Ousseyni Zika Oumou Moussa Djibrilla +7 位作者 Ataigba Iréti Néthania Elie Salifou A. M. Mobarak Daou Mamane Nanéma Désiré Abdou Bakari Sangaré Ismaël Coulibaly Modibo Douma Maiga Djibo Ouédraogo Arouna 《Open Journal of Psychiatry》 2025年第1期24-34,共11页
This study aims to explore the unconscious motivations underlying migration in Niger, with an emphasis on understanding the phenomenon of pathological travel. Its aim is to identify the unconscious factors of patholog... This study aims to explore the unconscious motivations underlying migration in Niger, with an emphasis on understanding the phenomenon of pathological travel. Its aim is to identify the unconscious factors of pathological travel among migrants. Pathological travel, as discussed in the scientific literature on psychopathology, is characterised by movements initiated under the influence of delusions, hallucinations or other serious psychiatric disorders. The aim of this research is to contribute to our understanding of how these unconscious factors influence migration decisions. Using a retrospective analysis of five cases, this study examines the psychological and psychiatric dimensions of migration, particularly among patients referred to the psychiatry department of the Niamey National Hospital between 2017 and 2018. The five cases analysed, representing 12% of a cohort of 40 migrant patients, suffered from chronic psychotic disorders, including schizophrenia and chronic hallucinatory psychosis. By means of diagnostic interviews and categorical sorting, three main unconscious motivations were identified: the delusional state with themes of filiation and persecution, the hallucinations that dictated the travel behaviour, and the dissociative states manifested by depersonalisation and derealisation. It also emerges from this analysis that pathological travel often involves prolonged journeys on foot and without purpose. Thus, untreated mental illness plays a significant role in shaping and influencing individual and social behaviour. The results of this study have important implications for public health and migration policy. They highlight the need to integrate health assessments into migration management systems, particularly in regions serving as transit hubs for migrants. The research also highlights the need for culturally sensitive psychiatric interventions to address the interaction between pre-existing mental disorders and migration. This study contributes to a better understanding of the psychological dimensions of migration by highlighting the importance of addressing mental health as an integral part of humanitarian action. The knowledge gained paves the way for future research to explore this understudied aspect of migration on a broader scale. 展开更多
关键词 MIGRATION Mental Illness Pathological Journeys Unconscious Psychological Motivations NIGER
暂未订购
Consumption of Antihypertensive Drug in the Urban Area of Abobo (Abidjan, Ivory Coast)
2
作者 Gbongue Eric Tia Ahou Axelle Edith Kouadio +7 位作者 Amara Kamagate Moulad Ephraïm Alliman Goldberg Merveille Kouassi Amankou Donaldo Jean-Fabius Ahua Kouakou Emmanuel N’Gbra Assande Ange Auguste Effo Bosson Benjamin Aka N’Doua Gisèle Kouakou-Siransy 《Pharmacology & Pharmacy》 2025年第2期52-60,共9页
In Ivory Coast, arterial hypertension is 20.4% prevalent, with a high mortality rate. However, proper use of antihypertensive drugs can reduce the risks of morbidity and mortality associated with the disease. The aim ... In Ivory Coast, arterial hypertension is 20.4% prevalent, with a high mortality rate. However, proper use of antihypertensive drugs can reduce the risks of morbidity and mortality associated with the disease. The aim of this study was to determine the pattern of antihypertensive drugs in an urban population in Abidjan. To this end, a retrospective descriptive study was conducted. Data were collected from the consumption histories of several pharmacies in the Abobo commune of Abidjan between March and August 2020. Drugs available in pharmacies and containing one or more active ingredients in the ATC classification of antihypertensives were included. A total of 1082 sales of antihypertensives were recorded, with 53% of medicines containing a single molecule and 46% containing combinations of two molecules. Antihypertensives containing one active compound showed a high proportion of diuretics (28.7%), followed by calcium antagonists (20.35%) and beta-blockers (19.13%). The combination of ACE inhibitors and calcium antagonists was sold at 34.71%, with the combination of calcium antagonists/ACE inhibitors + diuretics (45.46%) in the two and three-molecule classes respectively. All in all, the study showed the patients were satisfied with the use of antihypertensives, with furosemide and the amlodipine/perindopril combination at the top of the list. 展开更多
关键词 CONSUMPTION ANTIHYPERTENSIVES HYPERTENSION
在线阅读 下载PDF
Distinct gut microbiomes in Thai patients with colorectal polyps 被引量:1
3
作者 Thoranin Intarajak Ahmad Nuruddin Khoiri +5 位作者 Kanthida Kusonmano Weerayuth Kittichotirat Sawannee Sutheeworapong Supapon Cheevadhanarak Wandee Udomchaiprasertkul Chinae Thammarongtham 《World Journal of Gastroenterology》 SCIE CAS 2024年第27期3336-3355,共20页
BACKGROUND Colorectal polyps that develop via the conventional adenoma-carcinoma sequence[e.g.,tubular adenoma(TA)]often progress to malignancy and are closely associated with changes in the composition of the gut mic... BACKGROUND Colorectal polyps that develop via the conventional adenoma-carcinoma sequence[e.g.,tubular adenoma(TA)]often progress to malignancy and are closely associated with changes in the composition of the gut microbiome.There is limited research concerning the microbial functions and gut microbiomes associated with colorectal polyps that arise through the serrated polyp pathway,such as hyperplastic polyps(HP).Exploration of microbiome alterations asso-ciated with HP and TA would improve the understanding of mechanisms by which specific microbes and their metabolic pathways contribute to colorectal carcinogenesis.AIM To investigate gut microbiome signatures,microbial associations,and microbial functions in HP and TA patients.METHODS Full-length 16S rRNA sequencing was used to characterize the gut microbiome in stool samples from control participants without polyps[control group(CT),n=40],patients with HP(n=52),and patients with TA(n=60).Significant differences in gut microbiome composition and functional mechanisms were identified between the CT group and patients with HP or TA.Analytical techniques in this study included differential abundance analysis,co-occurrence network analysis,and differential pathway analysis.RESULTS Colorectal cancer(CRC)-associated bacteria,including Streptococcus gallolyticus(S.gallolyticus),Bacteroides fragilis,and Clostridium symbiosum,were identified as characteristic microbial species in TA patients.Mediterraneibacter gnavus,associated with dysbiosis and gastrointestinal diseases,was significantly differentially abundant in the HP and TA groups.Functional pathway analysis revealed that HP patients exhibited enrichment in the sulfur oxidation pathway exclusively,whereas TA patients showed dominance in pathways related to secondary metabolite biosynthesis(e.g.,mevalonate);S.gallolyticus was a major contributor.Co-occurrence network and dynamic network analyses revealed co-occurrence of dysbiosis-associated bacteria in HP patients,whereas TA patients exhibited co-occurrence of CRC-associated bacteria.Furthermore,the co-occurrence of SCFA-producing bacteria was lower in TA patients than HP patients.CONCLUSION This study revealed distinct gut microbiome signatures associated with pathways of colorectal polyp development,providing insights concerning the roles of microbial species,functional pathways,and microbial interactions in colorectal carcinogenesis. 展开更多
关键词 Gut microbiome Colorectal adenoma Hyperplastic polyp Full-length 16s rRNA Microbial correlation networks Predicted functional mechanisms
暂未订购
Mechanism of Diabatic Heating on Precipitation and the Track of a Tibetan Plateau Vortex over the Eastern Slope of the Tibetan Plateau
4
作者 Yuanchang DONG Guoping LI +3 位作者 Xiaolin XIE Long YANG Peiwen ZHANG Bo ZENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期155-172,共18页
Existing studies contend that latent heating(LH)will replace sensible heating(SH)to become the dominant factor affecting the development of the Tibetan Plateau vortex(TPV)after it moves off the Tibetan Plateau(TP).How... Existing studies contend that latent heating(LH)will replace sensible heating(SH)to become the dominant factor affecting the development of the Tibetan Plateau vortex(TPV)after it moves off the Tibetan Plateau(TP).However,in the process of the TPV moving off the TP requires that the airmass traverse the eastern slope of the Tibetan Plateau(ESTP)where the topography and diabatic heating(DH)conditions rapidly change.How LH gradually replaces SH to become the dominant factor in the development of the TPV over the ESTP is still not very clear.In this paper,an analysis of a typical case of a TPV with a long life history over the ESTP is performed by using multi-sourced meteorological data and model simulations.The results show that SH from the TP surface can change the TPV-associated precipitation distribution by temperature advection after the TPV moves off the TP.The LH can then directly promote the development of the TPV and has a certain guiding effect on the track of the TPV.The SH can control the active area of LH by changing the falling area of the TPV-associated precipitation,so it still plays a key role in the development and tracking of the TPV even though it has moved out of the main body of the TP. 展开更多
关键词 eastern slope of the Tibetan Plateau diabatic heating Tibetan Plateau vortex precipitation distribution TRACK
在线阅读 下载PDF
Review of coastal land transformation:Factors,impacts,adaptation strategies,and future scopes
5
作者 Md.Abubakkor Siddik Abu Reza Md.Towfiqul Islam 《Geography and Sustainability》 CSCD 2024年第2期167-178,共12页
Coastal land transformation has been identified as a topic of research in many countries around the world.Several studies have been conducted to determine the causes and impacts of land transformation.However,much les... Coastal land transformation has been identified as a topic of research in many countries around the world.Several studies have been conducted to determine the causes and impacts of land transformation.However,much less is understood about coupling change detection,factors,impacts,and adaptation strategies for coastal land transformation at a global scale.This review aims to present a systematic review of global coastal land transformation and its leading research areas.From 1,741 documents of Scopus and Web of Science,60 studies have been selected using the PRISMA-2020 guideline.Results revealed that existing literature included four leading focus areas regarding coastal land transformation:change detection,driving factors,impacts,and adaptation measures.These focus areas were further analyzed,and it was found that more than 80%of studies used Landsat imagery to detect land transformation.Population growth and urbanization were among the major driving factors identified.This review further identified that about 37%of studies included impact analysis.These studies identified impacts on ecosystems,land surface temperature,migration,water quality,and occupational effects as significant impacts.However,only four studies included adaptation strategies.This review explored the scope of comprehensive research in coastal land transformation,addressing change detection,factor and impact analysis,and mitigation-adaptation strategies.The research also proposes a conceptual framework for comprehensive coastal land transformation analysis.The framework can provide potential decision-making guidance for future studies in coastal land transformation. 展开更多
关键词 Coastal land transformation Land use and land cover LANDSAT POPULATION PRISMA
在线阅读 下载PDF
Synthesis of reduced graphene oxide nanosheets from sugarcane dry leaves by two-stage pyrolysis for antibacterial activity
6
作者 Baskar Thangaraj Pravin Raj Solomon +4 位作者 Nutthapon Wongyao Mohamed I.Helal Ali Abdullah Sufian Abedrabbo Jamal Hassan 《Nano Materials Science》 EI CAS CSCD 2024年第5期625-634,共10页
Oxidative-exfoliation methods were in vogue in the production of rGO from graphite.Processing of such synthetic graphite needs high temperatures(2500℃).Thus,such process is not cost-effective.The present study is mad... Oxidative-exfoliation methods were in vogue in the production of rGO from graphite.Processing of such synthetic graphite needs high temperatures(2500℃).Thus,such process is not cost-effective.The present study is made on the dry leaves of sugarcane(Saccharum officinarum)as an alternative raw material so as to be economical and environmentally benign.The dry leaves are subjected to two-step pyrolysis without any catalyst or reducing agent in far divergent temperatures to produce as prepared and acid treated rGOs.They were evaluated by UV–Vis.,FTIR,XRD,Raman spectroscopy,TGA/DTG,BET,FESEM-EDS and TEM.The as prepared rGO has few layers with irregular and folded architecture whereas acid-treated rGO has thinly stacked crumpled sheets with many wrinkles on its surface.The prepared rGOs have multilayered graphitic structure due to the unique ratio between G and D bands.Acid treated rGO has poor thermal stability as compared to that of as-prepared rGO at high temperatures due to the variation in the oxygen-containing functional groups.Acid treated rGO has low antibacterial activity as compared to that of the as-prepared rGO due to the paucity of the functional groups. 展开更多
关键词 Biomass wastes Sugarcane dry leaves PYROLYSIS Reduced graphene oxide Antibacterial activity
在线阅读 下载PDF
Heavy Metal Levels and Ecological Risk in Crude Oil-Contaminated Soils from Okpare-Olomu, Niger Delta, Nigeria
7
作者 Adedoyin Olubunmi Bankole Akinyemi Olufemi Ogunkeyede +5 位作者 Harrison Agboro Prince Alex Ekhorutomwen Osasenaga Israel Otuomagie Khadijah Ateda Isimekhai Ekaette Akpan Fadairo Efe Jeffery Isukuru 《Journal of Environmental Protection》 2024年第4期415-438,共24页
Crude oil spills have inflicted extensive disruption upon the Niger Delta ecosystem, resulting in crop loss and severe environmental damage. Such spills exacerbate heavy metal concentration within soil due to the pres... Crude oil spills have inflicted extensive disruption upon the Niger Delta ecosystem, resulting in crop loss and severe environmental damage. Such spills exacerbate heavy metal concentration within soil due to the presence of metallic ions. The Okpare-Olomu community has borne the brunt of crude oil pollution from illicit bunkering, sabotage, and equipment malfunction. This study targets an evaluation of ecological hazards linked to heavy metals (HMs) in crude oil impacted agriculturally soils within Okpare-Olomu in Ughelli South LGA of Delta State. In this study, 24 topsoil samples were obtained from areas affected by crude oil pollution;the heavy metal content was evaluated through atomic absorption spectrometry. The concentration ranges for HMs (mg/kg) in soil were: 24.1 - 23,174 (Cu);0.54 - 37.1 (Cd);9.05 - 54 (Cr);12 - 174 (Ni);18.5 - 8611 (Pb);and 148 - 9078 (Zn) at a soil depth of 0 - 15 cm. Notably, metal concentrations were recorded to be above permissible World Health Organization limits. Predominantly, Zn and Pb recorded higher heavy metal concentration when compared to other heavy metals analysed, notably at sampling points PT7 through PT24. Zinc and Pb contamination exhibited highly significant contamination factors, and contamination severity was evidenced across all sample points, signifying a grave risk level. Pollution load indices indicated pervasive extreme pollution levels. Geoaccumulation indices signaled moderate to strong pollution, mainly by Pb and Zn. Ecological risk assessments revealed variable levels of heavy metal contamination, from low to very high, with potential ecological risk reflecting markedly elevated levels. This study underscores the imperative for soil remediation to rectify ecological imbalances in agriculturally affected soil constituents. 展开更多
关键词 Heavy Metals Crude Oil POLLUTION Degree of Contamination Potential Risk Index
在线阅读 下载PDF
Effect of the Implementation of Emonc in the Reduction of Maternal Deaths in the Department of Collines from 2018 to 2022
8
作者 Joachim Aifa Florence Abraham +2 位作者 Roger Klikpezo Edgard-Marius Ouendo Badirou Aguemon 《Open Journal of Obstetrics and Gynecology》 2024年第2期259-266,共8页
Background: Maternal and neonatal mortality remains a public health problem in Benin. Each year, approximately 1500 maternal deaths and more than 12,000 newborn deaths are recorded there. In order to correct the situa... Background: Maternal and neonatal mortality remains a public health problem in Benin. Each year, approximately 1500 maternal deaths and more than 12,000 newborn deaths are recorded there. In order to correct the situation, strategies such as the implementation of Emergency Obstetric and Neonatal Care (EmONC) were initiated. Objective: Determine the rates of maternal deaths in EmONC centers in the Collines department from 2018 to 2022. Framework and Methods: The study took place in Benin precisely in the Collines department. This was a descriptive cross-sectional study. Data collection was carried out during the first two weeks of January 2023 and covered data from the 09 Basic Emergency Obstetric and Neonatal Care centers (BEMONC) and the Obstetric and Neonatal Care centers of Complete Emergency (CEmONC) of the Collines department from 2018 to 2022. An estimate of the ratios of maternal deaths occurring at the level of the EmONC centers of the Collines department from 2018-2022 was carried out followed by constructive suggestions. Results: During the five years (2018 to 2022), the Collines department recorded 42,582 live births with 148 maternal deaths, i.e. a ratio of 348 maternal deaths per 100,000 live births. Between 2018 and 2022, the highest maternal death ratio was recorded in 2019, i.e. 425 maternal deaths per 100,000 live births for all EmONC centers and 607 maternal deaths per 100,000 live births in EmONC centers. The highest maternal death ratio at the BEmONC center level was recorded in 2020, i.e. 129 maternal deaths per 100,000 births. Conclusion: These results suggest that despite the implementation of EmONC in the Collines department, maternal deaths have not decreased. To improve these outcomes for a reduction in maternal deaths, urgent action must be taken. 展开更多
关键词 EFFECT BEmONC CEmONC Maternal deaths Department of Collines
在线阅读 下载PDF
Flora, Structure and Carbon Sequestration of Vegetation in the Southeast of the Mono Biosphere Reserve in Togo Amidst Environmental Challenges
9
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
在线阅读 下载PDF
Mineralogical and Geochemical Characterisation of Rocks and Geothermal Fluids in the Olkaria Geothermal Field, Kenya: Potential for Epithermal Deposits
10
作者 Christine Jerotich Kiptoo Isaac Kanda +2 位作者 Nicholas Mariita Patrick Kariuki Patrick Kirita Gevera 《International Journal of Geosciences》 2024年第12期1113-1133,共21页
The Kenyan Olkaria geothermal field has incredibly high geothermal potential in the East African Rift, the Kenyan Rift Valley. While the Olkaria geothermal area has been primarily attributed to electricity generation ... The Kenyan Olkaria geothermal field has incredibly high geothermal potential in the East African Rift, the Kenyan Rift Valley. While the Olkaria geothermal area has been primarily attributed to electricity generation and direct uses, this research investigates the potential of epithermal deposits in the geothermal systems with particular interests in base metals (Zn, Pb, and Fe) and alkali metals (Li, Na, K) in geothermal rocks and fluids. The study employed geochemical, geological, and well-logging analyses to characterise and assess the conditions in the geothermal system suitable for forming and depositing epithermal minerals. Rock cuttings and fluid samples were collected from geothermal wells, fumaroles, and hot springs. Findings indicate that the mineralisation in the Olkaria wells occurs in microveins and disseminations in the rock matrix, majorly sulfides, and oxides in hydrothermal alteration zones. The reported Zn, Pb, and Fe mineralisation mainly relates to low sulphidation type from the characterised sulphur metal complexes and oxides. Fluid samples recorded the metals as follows: Fe (0.12 - 3.9 ppm), Zn (4.21 - 5.23 ppm), Pb (1.55 - 2.04 ppm), and lithium concentrations at ≤ 3 ppm, which is lower than extractible values in geothermal brines in the Salton Sea and geothermal fields of Europe. The economic characterisation of rocks and fluid samples in our area indicates that the concentration of base and alkali metals has not yielded economically viable values compared to other geothermal systems with economic grades. Detailed studies are recommended to quantify mineralisation in Olkaria geothermal fields and their extractability for sustainable management of the geothermal resource. 展开更多
关键词 East Africa Rift System (EARS) Epithermal Deposits GEOCHEMISTRY Geothermal Systems
在线阅读 下载PDF
Place of Bone Scintigraphy in the Assessment of Extension and Follow-Up of Breast Cancer in Senegal: Study of 165 Cases in the Nuclear Medicine Department of Idrissa Pouye General Hospital (Dakar)
11
作者 El Hadji Amadou Lamine Bathily Mamoudou Salif Djigo +7 位作者 Djimby Ba Gora Thiaw Ousseynou Diop Kalidou Gueye Olatounde Herbert Fachinan Boucar Ndong Omar Ndoye Mamadou Mbodj 《Open Journal of Medical Imaging》 2024年第1期10-30,共21页
Introduction: Breast cancer is the most common cancer in women worldwide, accounting for an estimated 22% of all female cancers. It is the leading cause of cancer mortality in women, almost all of which is due to meta... Introduction: Breast cancer is the most common cancer in women worldwide, accounting for an estimated 22% of all female cancers. It is the leading cause of cancer mortality in women, almost all of which is due to metastases, with 73% of metastases occurring in the bone. In oncology, metastable technetium 99-labelled methylene bisphosphonate bone scintigraphy (BS) remains the standard examination for detecting and assessing the extent of bone metastases. The aim of this study was to assess the role of BS in the evaluation and follow-up of breast cancer in Senegal. Methodology: This was a retrospective study of breast cancer patients who underwent bone scintigraphy with <sup>99m</sup>Tc-HMDP in the nuclear medicine department of Idrissa Pouye General Hospital (IPGHO), from July 2009 to June 2022. Results: We enrolled 165 patients, mean age 46.79 years (27 - 87 years). BS was performed in 94.37% of cases for post-therapeutic monitoring and in 5.63% for pre-therapeutic assessment. Results were contributory in 131 patients (92.25%), of whom 72 cases (50.70%) were normal and 59 cases (41.55%) positive or presenting bone metastases;and non-contributory or doubtful in 11 cases (7.75%). Secondary bone locations were multiple in 57 cases (96.61%) and single or solitary in 2 cases (3.39%). The scintigraphic appearance of bone metastases was hyper-fixative in 58 cases (98.31%) and mixed in 1 case (1.69%). Bone lesions were quantified using the Soloway’s grading classification. Conclusion: BS with <sup>99m</sup>Tc-labelled bisphosphonates remains the examination of choice for skeletal exploration, in the detection and extension of bone metastases in breast cancer. Performance has been enhanced by the development of SPECT coupled with CT (SPECT-CT). 展开更多
关键词 Breast Cancer Bone Scintigraphy 99mTc-HMDP Bone Metastases
暂未订购
网络病毒的求源问题
12
作者 韩兰胜 韩淑霞 Varney Washington 《计算机科学》 CSCD 北大核心 2006年第9期8-11,82,共5页
现有的网络病毒方面的文章大都强调网络病毒与生物病毒的相似性,而生物病毒的寻源具有很多不确定因素,因此很少有人提出网络病毒寻源的理论。本文强调网络病毒的传播不同于生物病毒的传播,它的传播信息是可以通过网络获取的;病毒的求... 现有的网络病毒方面的文章大都强调网络病毒与生物病毒的相似性,而生物病毒的寻源具有很多不确定因素,因此很少有人提出网络病毒寻源的理论。本文强调网络病毒的传播不同于生物病毒的传播,它的传播信息是可以通过网络获取的;病毒的求源虽然是病毒传播的逆过程,但它也不同于严格意义上的反问题。文章提出子网内病毒传播路径的始点即为子网的病毒源。指出病毒的传播引起的计算机结点的状态变迁是获取病毒实际传播路径的主要依据,而计算机感染病毒的诊断和清毒是获取该依据的重要手段。由此,文章建立了子网的状态变迁方程。结合实际的网络因素和实践,文章给出了一套求解的方法和步骤,反复求解子网的状态变迁方程即可求得病毒实际传播的路径,传播路径的始点即为病毒的一个源点。最后,文章对模型及其解法给出了模拟实验,实验证明了理论模型的正确性和求解方法的有效性。文章为建立网络病毒的求源理论打开了一定的思路。 展开更多
关键词 网络病毒 网络安全 病毒求源
在线阅读 下载PDF
Molecular mechanisms of viral hepatitis induced hepatocellular carcinoma 被引量:47
13
作者 Simmone D'souza Keith CK Lau +1 位作者 Carla S Coffin Trushar R Patel 《World Journal of Gastroenterology》 SCIE CAS 2020年第38期5759-5783,共25页
Chronic infection with viral hepatitis affects half a billion individuals worldwide and can lead to cirrhosis,cancer,and liver failure.Liver cancer is the third leading cause of cancer-associated mortality,of which he... Chronic infection with viral hepatitis affects half a billion individuals worldwide and can lead to cirrhosis,cancer,and liver failure.Liver cancer is the third leading cause of cancer-associated mortality,of which hepatocellular carcinoma(HCC)represents 90%of all primary liver cancers.Solid tumors like HCC are complex and have heterogeneous tumor genomic profiles contributing to complexity in diagnosis and management.Chronic infection with hepatitis B virus(HBV),hepatitis delta virus(HDV),and hepatitis C virus(HCV)are the greatest etiological risk factors for HCC.Due to the significant role of chronic viral infection in HCC development,it is important to investigate direct(viral associated)and indirect(immune-associated)mechanisms involved in the pathogenesis of HCC.Common mechanisms used by HBV,HCV,and HDV that drive hepatocarcinogenesis include persistent liver inflammation with an impaired antiviral immune response,immune and viral protein-mediated oxidative stress,and deregulation of cellular signaling pathways by viral proteins.DNA integration to promote genome instability is a feature of HBV infection,and metabolic reprogramming leading to steatosis is driven by HCV infection.The current review aims to provide a brief overview of HBV,HCV and HDV molecular biology,and highlight specific viral-associated oncogenic mechanisms and common molecular pathways deregulated in HCC,and current as well as emerging treatments for HCC. 展开更多
关键词 Chronic viral infection Hallmarks of cancer Hepatocellular carcinoma Hepatitis B virus Hepatitis C virus Hepatitis delta virus co-infection Molecular mechanisms Viral hepatitis
暂未订购
印度小圆胸小蠹的一种新寄主植物(英文) 被引量:7
14
作者 Rajesh KUMAR Girin RAJKHOWA Mattipalli SANKAR Rama Krishnan RAJAN 《昆虫学报》 CAS CSCD 北大核心 2011年第6期734-738,共5页
自然条件下印度小圆胸小蠹Euwallacea fornicatus(Eichhoff,1868)在茶树枝条虫瘿内取食,是茶的重要害虫之一,以茶蛀虫著称。2010年5-8月,在印度MugaEri研究中心3号农场(Lahdoigarh,Jorhat-Assam)的黄心树Persea bombycina Kost.(樟科)... 自然条件下印度小圆胸小蠹Euwallacea fornicatus(Eichhoff,1868)在茶树枝条虫瘿内取食,是茶的重要害虫之一,以茶蛀虫著称。2010年5-8月,在印度MugaEri研究中心3号农场(Lahdoigarh,Jorhat-Assam)的黄心树Persea bombycina Kost.(樟科)种植园中发现该虫有自然分布,且已对黄心树造成了明显的危害。黄心树为小圆胸小蠹一种新纪录的寄主植物。本文对小圆胸小蠹的寄主范围、分布、生物学和生活史等进行了讨论。 展开更多
关键词 茶蛀虫 小圆胸小蠹 黄心树 生物学 生活史
原文传递
Neural-fuzzy control system application for monitoring process response and control of anaerobic hybrid reactor in wastewater treatment and biogas production 被引量:8
15
作者 Chaiwat Waewsak Annop Nopharatana Pawinee Chaiprasert 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第12期1883-1890,共8页
Based on the developed neural-fuzzy control system for anaerobic hybrid reactor (AHR) in wastewater treatment and biogas production, the neural network with backpropagation algorithm for prediction of the variables ... Based on the developed neural-fuzzy control system for anaerobic hybrid reactor (AHR) in wastewater treatment and biogas production, the neural network with backpropagation algorithm for prediction of the variables pH, alkalinity (Alk) and total volatile acids (TVA) at present day time t was used as input data for the fuzzy logic to calculate the influent feed flow rate that was applied to control and monitor the process response at different operations in the initial, overload influent feeding and the recovery phases. In all three phases, this neural-fuzzy control system showed great potential to control AHR in high stability and performance and quick response. Although in the overloading operation phase II with two fold calculating influent flow rate together with a two fold organic loading rate (OLR), this control system had rapid response and was sensitive to the intended overload. When the influent feeding rate was followed by the calculation of control system in the initial operation phase I and the recovery operation phase III, it was found that the neural-fuzzy control system application was capable of controlling the AHR in a good manner with the pH close to 7, TVA/Alk 〈 0.4 and COD removal 〉 80% with biogas and methane yields at 0.45 and 0.30 m^3/kg COD removed. 展开更多
关键词 anaerobic hybrid reactor influent feed flow rate neural-fuzzy control system process response
原文传递
Combination eect of pH and acetate on enzymatic cellulose hydrolysis 被引量:8
16
作者 ROMSAIYUD Angsana SONGKASIRI Warinthorn +1 位作者 NOPHARATANA Annop CHAIPRASERT Pawinee 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第7期965-970,共6页
The productivity and efficiency of cellulase are significant in cellulose hydrolysis. With the accumulation of volatile fatty acids (VFAs), the pH value in anaerobic digestion system is reduced. Therefore, this stud... The productivity and efficiency of cellulase are significant in cellulose hydrolysis. With the accumulation of volatile fatty acids (VFAs), the pH value in anaerobic digestion system is reduced. Therefore, this study will find out how the pH and the amount of acetate influence the enzymatic hydrolysis of cellulose. The effects of pH and acetate on cellulase produced from Bacillus coagulans were studied at various pH 5-8, and acetate concentrations (0-60 mmol/L). A batch kinetic model for enzymatic cellulose hydrolysis was constructed from experimental data and performed. The base hypothesis was as follows: the rates of enzymatic cellulose hydrolysis rely on pH and acetate concentration. The results showed that the suitable pH range for cellulase production and cellulose hydrolysis (represents efficiency of cellulase) was 2.6-7.5, and 5.3-8.3, respectively. Moreover, acetate in the culture medium had an effect on cellulase production (KI = 49.50 mmol/L, n = 1.7) less than cellulose hydrolysis (/('i = 37.85 mmol/L, n = 2.0). The results indicated that both the pH of suspension and acidogenic products influence the enzymatic hydrolysis of cellulose in an anaerobic environment. To enhance the cellulose hydrolysis rate, the accumulated acetate concentration should be lower than 25 mmol/L, and pH should be maintained at 7. 展开更多
关键词 ACETATE Bacillus coagulans CELLULASE CELLULOSE hydrolysis kinetics
在线阅读 下载PDF
Influence of abrasive hardness on erosion wear of abrasive air jets 被引量:8
17
作者 LIU Yong CHEN Chang-jiang +2 位作者 WEI Jian-ping LIU Xiao-tian WANG Xiang-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期356-371,共16页
To make clear the influence of abrasive hardness on the erosion effect,the erosion experiments of abrasive air jet with the same impact energy were carried out.The influence of abrasive hardness on the erosion effect ... To make clear the influence of abrasive hardness on the erosion effect,the erosion experiments of abrasive air jet with the same impact energy were carried out.The influence of abrasive hardness on the erosion effect is clarified by comparing the different erosion depths.The main conclusions are as follows.Under the same mass flow rate and mesh number,the abrasive with a higher density needs greater pressure irrespective of hardness.After erosion damage,the abrasive size exhibits a Weibull distribution.The shape parameterβand Weibull distribution function of four types of abrasives are derived by the least squares method;moreover,βis found to have a quadratic relation with abrasive hardness.The results of the erosion experiments show that abrasive hardness and erosion depth are quadratically related.By calculating the increase in surface energy after abrasive erosion crushing,it is found that abrasive hardness has a quadratic relation with surface energy and that the increases in erosion depth and surface energy consumption are basically identical.In conclusion,the effect is a soft abrasive impact when the ratio of abrasive hardness(Ha)to the material hardness(Hm)is<2.6,and it is a hard abrasive impact when Ha/Hm>3. 展开更多
关键词 abrasive air jet abrasive hardness rock erosion abrasive size distribution coal bed methane
在线阅读 下载PDF
不同水分含量桑叶对二化性家蚕的营养效应(英文) 被引量:2
18
作者 V.K.RAHMATHULLA M.T.HIMANTHARAJ +1 位作者 G.SRINIVASA R.K.RAJAN 《昆虫学报》 CAS CSCD 北大核心 2004年第6期701-704,共4页
研究了取食不同水分含量桑叶对二化性家蚕 (CSR3×CSR6 ) 5龄幼虫的影响。实验设嫩叶 (水分含量 80 %~ 85 % )、半成熟叶 (水分含量 6 5 %~ 70 % )和成熟叶 (水分含量 5 5 %~ 6 0 % ) 3个不同处理。采用标准重量分析法分析和计... 研究了取食不同水分含量桑叶对二化性家蚕 (CSR3×CSR6 ) 5龄幼虫的影响。实验设嫩叶 (水分含量 80 %~ 85 % )、半成熟叶 (水分含量 6 5 %~ 70 % )和成熟叶 (水分含量 5 5 %~ 6 0 % ) 3个不同处理。采用标准重量分析法分析和计算各种生长、营养和营养效率指数。结果表明 ,在取食较高水分含量桑叶的处理中 ,营养指数 (包括取食量、消化量和近似消化率等 )和营养效率指数 (包括食物利用率和转化率等 )均显著较高 ,但不同处理中消化食物向茧壳的转化率及产生每克茧壳所需食物消化量差异不明显。 展开更多
关键词 家蚕 桑叶水分含量 食物利用率 消化 吸收 能量转换
在线阅读 下载PDF
Source identification, contamination status and health risk assessment of heavy metals from road dusts in Dhaka, Bangladesh 被引量:5
19
作者 Aklima Nargis Ahsan Habib +6 位作者 Md Nazrul Islam Kai Chen Md Shafiqul Islam Sarker A N M Al-Razee Wenbin Liu Guorui Liu Minggang Cai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第11期159-174,共16页
In this study, concentrations of Cr, Mn, Ni, Cu, Zn, Cd and Pb were determined in road dusts collected from different locations in Dhaka to assess source, contamination status and health risk. Energy-dispersive X-ray ... In this study, concentrations of Cr, Mn, Ni, Cu, Zn, Cd and Pb were determined in road dusts collected from different locations in Dhaka to assess source, contamination status and health risk. Energy-dispersive X-ray fluorescence spectroscopy and energy-dispersive X-ray spectroscopy were used to determine Cr, Mn, Ni, Cu, Zn, Cd and Pb and their mean concentrations were 162.27 ± 29.46, 721.18 ± 180.14, 35.65 ± 12.55, 104.56 ± 128.33, 515.32 ± 321.90,BDL, and 342.82 ± 591.20 mg/kg, respectively. Among the heavy metals, highest concentrations of Cu, Zn and Pb were found at urban sites-7(municipal waste dumping) and 8(medical waste incineration). Highest concentration of Cr followed by Cu and Zn was found at site-5(Tejgaon, urban). Principal component analysis revealed that anthropogenic activities are the potential sources for Cr, Ni, Cu, Zn and Pb while earth crust for Mn. Pollution index and pollution load index results suggested that all the sites were contaminated and/or degraded by Cr, Cu, Zn and Pb except sites-9(urban), 10(sub-urban), 11(rural) while sites-7 and 8(urban) were extremely degraded. For noncarcinogenic health risk, hazard quotient values for dermal were higher compared to that of inhalation/ingestion. Though hazard index values were less than 1 at all the sites, these were at least one order of magnitude higher for children group than that of adult group, thus the children group may face more noncarcinogenic health risk at sites -7 and 8. Values of incremental lifetime cancer risk were from 10to 10showed no carcinogenic health risk by road dusts contaminated with the heavy metals. 展开更多
关键词 Heavy metal Road dust Dhaka Principal component analysis Pollution status Health risk assessment
原文传递
Local communities' participation in decision-making processes through planning and budgeting in African countries 被引量:2
20
作者 Leonard I.Chirenje Richard A.Giliba Emmanuel B.Musamba 《Chinese Journal of Population,Resources and Environment》 2013年第1期10-16,共7页
Community participation and community based management are topical themes in current policy and discussion revolving around decision-making processes especially those dealing with natural resources management.This rev... Community participation and community based management are topical themes in current policy and discussion revolving around decision-making processes especially those dealing with natural resources management.This review shows that while governments have accepted the need to either cede or devolve control and management of natural resources to the local communities,the communities are not part and parcel of the planning and budgeting which are crucial in decisionmaking.Communities were seen to be more involved in the implementation of natural resource management programs but lacked ownership of the projects.This causes lack of commitment to the programs and at times hostile reaction from the communities.The communities are always at the receiving end when it pertains to losses in the exchange.Community participation was shown to be effective when the local population is involved not as co-operating users but as natural resource managers or owner managers. 展开更多
关键词 DECISION-MAKING community PARTICIPATION natural resources management PLANNING BUDGETING
在线阅读 下载PDF
上一页 1 2 6 下一页 到第
使用帮助 返回顶部