检索结果-南通市图书馆

Oxidized organic molecules in the tropical free troposphere over Amazonia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2024年第1期11卷 174-184页

作者： Qiaozhi Zha Diego Aliaga Radovan Krejci Victoria A.Sinclair Cheng Wu Giancarlo Ciarelli Wiebke Scholz Liine Heikkinen Eva Partoll Yvette Gramlich Wei Huang Markus Leiminger Joonas Enroth Otso Per?kyl? Runlong Cai Xuemeng Chen Alkuin Maximilian Koenig Fernando Velarde Isabel Moreno Tuukka Pet?j? Paulo Artaxo Paolo Laj Armin Hansel Samara Carbone Markku Kulmala Marcos Andrade douglas Worsnop Claudia Mohr Federico Bianchi Institute for Atmospheric and Earth System Research/Physics University of Helsinki Joint International Research Laboratory of Atmospheric and Earth System Sciences Nanjing University Department of Environmental Science & Bolin Centre for Climate Research Stockholm University Department of Chemistry and Molecular Biology University of Gothenburg Institute for Ion and Applied Physics University of Innsbruck Ionicon Analytik GmbH Laboratory for Atmospheric Physics Institute for Physics Research Universidad Mayor de San Andrés Institute of Physics University of Sao Paulo Institute for Geosciences and Environmental Research (IGE) University of Grenoble Alpes Agrarian Sciences Institute Federal University of Uberl?ndia Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Department of Atmospheric and Oceanic Sciences University of Maryland Aerodyne Research Inc. Department of Environmental System Science ETH Zürich Switzerland and Laboratory of Atmospheric Chemistry Paul Scherrer Institute

New particle formation(NPF) in the tropical free troposphere(FT) is a globally important source of cloud condensation nuclei, affecting cloud properties and climate. Oxidized organic molecules(OOMs)produced from biogenic volatile organic compounds are believed to contribute to aerosol formation in the tropical FT, but without direct chemical observations. We performed in situ molecular-level OOMs measurements at the Bolivian station Chacaltaya at 5240 m above sea level, on the western edge of Amazonia. For the first time, we demonstrate the presence of OOMs, mainly with 4–5 carbon atoms, in both gas-phase and particle-phase(in terms of mass contribution) measurements in tropical FT air from Amazonia. These observations, combined with air mass history analyses, indicate that the observed OOMs are linked to isoprene emitted from the rainforests hundreds of kilometers away. Based on particle-phase measurements, we find that these compounds can contribute to NPF, at least the growth of newly formed nanoparticles, in the tropical FT on a continental scale. Thus, our study is a fundamental and significant step in understanding the aerosol formation process in the tropical FT.

关键词： oxidized organic molecules tropical aerosol formation Amazon free troposphere

Forests,atmospheric water and an uncertain future: the new biology of the global water cycle

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Forest Ecosystems 2018年第3期5卷 236-257页

作者： douglas Sheil Faculty of Environmental Sciences and Natural Resource Management(MINA) Norwegian University of Life Sciences (NMBU)

Theory and evidence indicate that trees and other vegetation influence the atmospheric water-cycle in various *** influences are more important, more complex, and more poorly characterised than is widely *** there is little doubt that changes in tree cover will impact the water-cycle, the wider consequences remain difficult to predict as the underlying relationships and processes remain poorly characterised. Nonetheless, as forests are vulnerable to human activities, these linked aspects of the water-cycle are also at risk and the potential consequences of large scale forest loss are severe. Here, for non-specialist readers, I review our knowledge of the links between vegetation-cover and climate with a focus on forests and rain(precipitation). I highlight advances, uncertainties and research opportunities. There are significant shortcomings in our understanding of the atmospheric hydrological cycle and of its representation in climate models. A better understanding of the role of vegetation and tree-cover wil reduce some of these shortcomings. I outline and il ustrate various research themes where these advances may be *** themes include the biology of evaporation, aerosols and atmospheric motion, as well as the processes that determine monsoons and diurnal precipitation cycles. A novel theory—the ‘biotic pump’—suggests that evaporation and condensation can exert a major influence over atmospheric dynamics. This theory explains how high rainfall can be maintained within those continental land-masses that are sufficiently forested. Feedbacks within many of these processes can result in non-linear behaviours and the potential for dramatic changes as a result of forest loss(or gain): for example, switching from a wet to a dry local climate(or visa-versa). Much remains unknown and multiple research disciplines are needed to address this: forest scientists and other biologists have a major role to *** ideas, methods and data offer opportun

关键词： Biotic pump Climate Condensation Evaporation Ice-nucleation Transpiration GCM Vapour Water-cycle

Analysis of Factors Associated with the Abandonment of Nutritional Recovery among Parents of Severely Malnourished Children Aged 6 to 59 Months in the Health District of Titao, Burkina Faso

在线全文

学校读者我要写书评

暂无评论

Open Journal of Nursing 2024年第9期14卷 477-490页

作者： Aminata Gansore Patrice Ngangue Birama Apho Ly Ludovic K. N’Tcha douglas Mbang Massom Gbètogo Maxime Kiki Josiane Seu Nestor Bationo Noufou Gustave Nana Fla Koueta Institute for Interdisciplinary Training and Research in Health and Education Sciences Ouagadougou Burkina Faso Faculty of Nursing Laval University Quebec Canada Faculty of Medicine and Odonto Stomatology University of Sciences Techniques and Technology of Bamako Bamako Mali Centre de Recherche Entomologique de Cotonou Cotonou Benin Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Centre for Interdisciplinary Research in Rehabilittaion and Social Integration (CIRRIS) Laval University Quebec Canada Faculty of Health Sciences Joseph Ki-Zerbo University Ouagadougou Burkina Faso

Introduction: In Burkina Faso, undernutrition is a public health problem associated with more than 40% of infant and child mortality. Undernutrition management is complex, and there is often a risk of treatment abandonment. Studies on this topic have not explored the influence of environmental and therapeutic factors on parental compliance. This study proposes an analysis of factors influencing the abandonment of nutritional recovery by parents of malnourished children aged 6 to 59 months in ambulatory care. Methods: This was a descriptive and exploratory qualitative study. Data collection took place in February 2020. Data were collected from seventeen (17) participants via in-depth interviews (IDI) and direct observation. The IDIs were transcribed verbatim and thematically analyzed using Nvivo software. Results: The results revealed that factors related to the physical environment, such as geographical inaccessibility, pastoral occupation, displacement at auriferous sites, and insecurity, are important causes of nutritional recovery abandonment. They also prove that factors related to the social environment, such as lack of family and social support, feelings of shame, stigmatization, occupation of the mother, and social events, lead to this abandonment. In addition, therapeutic factors such as interruptions of supplies of Ready to Use Therapeutic Food (RUTF), feeling of improvement or worsening of the state of health, recourse to traditional medicine, and ignorance of undernutrition are also associated with this issue. Conclusion: This study highlighted barriers to the abandonment of nutritional recovery among parents of severely malnourished children aged 6 to 59 months in the health district of Titao, Burkina Faso. It is more important to consider these different factors when evaluating care protocols so that policies to reduce child undernutrition can considerably impact the targets.

关键词： Nutritional Recovery Severe Acute Malnutrition Environmental Factors Therapeutic Factors Abandonment Burkina Faso

Circulating microRNA expression and nonalcoholic fatty liver disease in adolescents with severe obesity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第4期30卷 332-345页

作者： Yi-Jie Li Brittney O Baumert Nikos Stratakis Jesse A Goodrich Hao-Tian Wu Jing-Xuan He Yin-Qi Zhao Max T Aung Hong-Xu Wang Sandrah P Eckel douglas I Walker Damaskini Valvi Michele A La Merrill Justin R Ryder Thomas H Inge Todd Jenkins Stephanie Sisley Rohit Kohli Stavra A Xanthakos Andrea A Baccarelli Rob McConnell David V Conti Lida Chatzi Department of Population and Public Health Sciences Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90032United States Barcelona Institute of Global Health Barcelona Institute of Global HealthBarcelona 08036Spain Department of Environmental Health Sciences Mailman School of Public HealthColumbia UniversityNew YorkNY 10032United States Gangarosa Department of Environmental Health Rollins School of Public HealthEmory UniversityAtlantaGA 30329United States Department of Environmental Medicine and Public Health Icahn School of Medicine at Mount SinaiNew YorkNY 10029United States Department of Environmental Toxicology University of CaliforniaDavisCA 95616United States Department of Surgery Lurie Children’s Hospital of ChicagoChicagoIL 60611United States Northwestern University Feinberg School of Medicine Northwestern UniversityChicagoIL 60611United States Division of Biostatistics and Epidemiology Cincinnati Children's Hospital Medical CenterCincinnatiOH 45229United States Department of Pediatrics University of Cincinnati College of MedicineCincinnatiOH 45229United States Department of Pediatrics Children’s Nutrition Research Center USDA/ARSBaylor College of MedicineHoustonTX 77030United States Department of Gastroenterology Children’s Hospital Los AngelesLos AngelesCA 90027United States Division of Gastroenterology Hepatology and NutritionCincinnati Children's Hospital Medical CenterCincinnatiOH 45229United States

BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic liver diseases in children and *** ranges in severity from isolated hepatic steatosis to nonalcoholic steatohepatitis(NASH),wherein hepatocellular inflammation and/or fibrosis coexist with *** microRNA(miRNA)levels have been suggested to be altered in NAFLD,but the extent to which miRNA are related to NAFLD features remains *** analysis tested the hypothesis that plasma miRNAs are significantly associated with histological features of NAFLD in *** To investigate the relationship between plasma miRNA expression and NAFLD features among adolescents with *** This study included 81 adolescents diagnosed with NAFLD and 54 adolescents without NAFLD from the Teen-Longitudinal Assessment of Bariatric Surgery ***-operative core liver biopsies were collected from participants and used to characterize histological features of *** samples were collected during surgery for miRNA profiling.A total of 843 plasma miRNAs were profiled using the HTG EdgeSeq *** examined associations of plasma miRNAs and NAFLD features using logistic regression after adjusting for age,sex,race,and other key *** Pathways Analysis was used to identify biological functions of miRNAs that were associated with multiple histological features of *** We identified 16 upregulated plasma miRNAs,including miR-193a-5p and miR-193b-5p,and 22 downregulated plasma miRNAs,including miR-1282 and miR-6734-5p,in adolescents with ***,52,16,15,and 9 plasma miRNAs were associated with NASH,fibrosis,ballooning degeneration,and lobular inflammation,***,16 miRNAs were associated with two or more histological features of *** those miRNAs,miR-411-5p was downregulated in NASH,ballooning,and fibrosis,while miR-122-5p,miR-1343-5p,miR-193a-5p,miR-193b-5p,and miR-7845-5p were consistently and posi

关键词： MicroRNA Nonalcoholic fatty liver disease Non-alcoholic steatohepatitis Liver fibrosis Lobular inflammation Ballooning degeneration

Urethroplasty among Elderly Men, Surgical Techniques and Outcomes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Urology 2024年第3期14卷 179-187页

作者： Kwaku Addai Arhin Appiah George Amoah Patrick Opoku Manu Maison Roland Azorliade Kwaku Otu-Boateng douglas Arthur Dominic Annor Mintah Joseph Yorke George Asafu Adjaye Frimpong Christian Kofi Gyasi-Sarpong Department of Surgery School of Medicine and Dentistry Kwame Nkrumah University of Science and Technology Kumasi Ghana Department of Surgery Komfo Anokye Teaching Hospital Kumasi Ghana Department of Surgery School of Medical Sciences University of Cape Coast Cape Coast Ghana Department of Radiology School of Medicine and Dentistry Kwame Nkrumah University of Science and Technology Kumasi Ghana

Introduction: Urethroplasty remains the gold standard for the management of urethral stricture. However, the treatment of stricture disease in the elderly tends to be less invasive due to the presumption that they might not be able to stand long hours of surgery and might have higher rates of recurrence due to poor wound healing from microangiopathy. We present our experience with the outcomes of urethroplasty among elderly men seen at the Komfo Anokye Teaching Hospital from January 2012 to December 2021. Methods: This was a retrospective review of data captured in the urology database on all patients 65 years and above who underwent urethroplasty at the hospital over the study period. Data was obtained on patients’ demographics, stricture characteristics, urethroplasty technique, and outcome. A successful outcome was defined as peak flow rate > 15 mls/s, a patent urethra on retrograde urethrogram, patient satisfaction with urine stream, or restoration of the normal stream of urine with only one attempt at urethral calibration or internal urethrotomy postoperatively. Data was analyzed using PASW Statistics for Windows, Version 18.0. Results: Overall, 43 urethroplasties were done over the study period in elderly men. The age range was 65 to 87 years. The commonest aetiology was catheterization (62.79%) followed by urethritis (32.56%). Stricture length ranged from 0.5 cm to 16 cm with a mean of 3.93 cm. Most patients (60.46%) had bulbar urethral strictures. The repair methods employed were anastomotic urethroplasty (62.80%), fasciocutaneous flap (FCF) ventral onlay (13.95%), buccal mucosa graft (BMG) ventral onlay urethroplasty (4.65%), and staged urethroplasty (4.65%). Three of the patients (6.98%) had a combination of anastomotic and tissue transfer urethroplasty. The overall success rate was 88.37%. Complications included three surgical site infections, two urethral diverticula and one glans dehiscence. Conclusion: Elderly men tolerate urethroplasty well and the pr

关键词： Urethral Stricture Elderly Men Urethroplasty Surgical Techniques

Materials and technology of Chinese jades dating to the Western Zhou period (1050―771 BCE)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2008年第4期51卷 467-480页

作者： Janet G douglas Department of Conservation and Scientific Research Freer Gallery of Art / Arthur M. Sackler Gallery Smithsonian Institution

Excavated jades dating to the Western Zhou period (1050―771 BCE) from the Xi’an area in Shaanxi Province, China, and contemporaneous jades in the collections of the Arthur M. Sackler Gallery at the Smithsonian Institution have been studied to learn about the jade and stone materials and how they were worked during the Western Zhou period. Materials identification was carried out using a combination of techniques such as Fourier-transform infrared spectroscopy and X-ray diffraction. Tool marks were studied using stereomicroscopy and examination of mold impressions using scanning electron microscopy. All of these objects were pro- duced through simple processes involving solid drilling, riffling, and sharp point abrasion; and no evidence was found for the use of rotary tools for incising or sawing.

关键词： jade nephrite stone China Western Zhou scanning electron microscopy materials technology tool marks

Interpreting forest diversity-productivity relationships:volume values,disturbance histories and alternative inferences

在线全文

学校读者我要写书评

暂无评论

Forest Ecosystems 2020年第1期7卷 64-75页

作者： douglas Sheil Frans Bongers Faculty of Environmental Sciences and Natural Resource Management(MINA) Norwegian University of Life Sciences(NMBU)Box 50031432 AsNorway Forest Ecology and Forest Management Group Wageningen University&ResearchPO Box 476700 AA WageningenThe Netherlands

Understanding the relationship between stand-level tree diversity and productivity has the potential to inform the science and management of *** shows that plant diversity-productivity relationships are challenging to interpret—and this remains true for the study of forests using non-experimental field *** we highlight pitfalls regarding the analyses and interpretation of such *** examine three themes:1)the nature and measurement of ecological productivity and related values;2)the role of stand history and disturbance in explaining forest characteristics;and 3)the interpretation of any *** show that volume production and true productivity are distinct,and neither is a demonstrated proxy for economic *** stand characteristics,including diversity,volume growth and productivity,vary intrinsically with succession and stand *** should be characterising these relationships rather than ignoring or eliminating *** to do so may lead to misleading *** illustrate,we examine the study which prompted our concerns—Liang et al.(Science 354:aaf8957,2016)—which developed a sophisticated global analysis to infer a worldwide positive effect of biodiversity(tree species richness)on“forest productivity”(stand level wood volume production).Existing data should be able to address many of our *** evaluations will improve understanding.

关键词： Causation Correlation Diversity Inference Productivity Richness Tree-growth Wood-density

The Effect of Natural Hazard Damage on Manufacturing Value Added and the Impact of Spatiotemporal Data Variations on the Results

在线全文

学校读者我要写书评

暂无评论

International Journal of Disaster Risk Science 2022年第5期13卷 691-704页

作者： douglas Thomas Jennifer Helgeson National Institute of Standards and Technology GaithersburgMD 20899USA

This study examined the effect of natural hazards on manufacturing industry value added and the sensitivity of the results from changes to spatiotemporal resolution of the *** measured the negative effects of hazards,rather than the net *** models were developed with varying spatio temporal units for the continental United States:annual/county units;annual/state units;and quarterly/state *** simulations were run using each model to estimate the negative effect of damage from all natural hazards on value added across spatiotemporal ***,an investment analysis was conducted to examine the return from public investments in hazard *** results do not demonstrate that,locally,natural hazards reduce value ***,the evidence suggests that natural hazards in the upstream supply chain have statistically significant impact when modeled at the annual/county scale and at the quarterly/state *** local nor supply chain hazards have a statistically significant effect when modeled at the annual/state scale,suggesting that broader spatiotemporal units may obscure the true downstream effects of natural *** investment analysis,utilizing model results,suggests that an investment of USD 100 billion or less is economical if it results in a reduction in losses of 10% or more.

关键词： Manufacturing Natural hazards Spatiotemporal impacts United States Value added

Slab and Level 2 Automation Design Guidelines for Optimum Metallurgy and Productivity for Plate and Steckel Mills

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2011年第S1期18卷 550-556页

作者： Stalheim douglas DGS Metallurgical Solutions Inc. 15003 NE 10th StreetVancouverWA 98684 USA

Many new steel plate processing facilities have been built in the past 10 years around the world with many more being planned for the *** is especially true in developing countries such as China,India and *** of these facilities are plate mills with either one or two stands or a Steckel mill,typically only one stand designed for the production of structural plate ***,there is a lack of understanding with both the mill builders of the world and the mill owners on the importance of properly matching up the available slab supply (either new as part of a new plate/Steckel mill complex or part of an already existing) with the desired end plate product *** mill builders and owners around the world believe that you can take any slab of any dimension and make any plate dimension you *** this is basically true with today’s Level 2 automation systems,it does not always result in optimum metallurgy/mechanical properties or *** less than optimum condition results in mechanical property failures,shape issues,productivity losses and in general a less than desirable costly processing *** is important to the overall optimization of a steel processing facility that the proper slab dimensions be used to produce the proper final plate dimensions along with achieving the required mechanical *** critical nature of this selection will be dependent on the final plate thickness and overall mechanical property *** mechanical property,shape and overall microstructure are heavily dependent on the ability to properly work the entire cross section of the slab through the rolling *** mechanical property,shape and microstructural issues are a result of improper working of the entire cross section during *** ability for a given mill to properly work the entire cross section is dependent on proper slab selection (total reduction ratio) and a proper rolling schedule either generated manual

关键词： slab dimensions optimization grain size rolling schedule automation Level 2