检索结果-南通市图书馆

World j.urnal of Clinical Pediatrics 2024年第3期13卷 137-140页

作者： Kevan j.English Department of Medicine-Pediatrics St.George's University School of MedicineSaint George's 33334Saint GeorgeGrenada

This article extends on the use of transabdominal intestinal ultrasound in diagnosing pediatric inflammatory bowel *** of the more essential features used in assessing bowel inflammation,such as hyperemia and wall thickness on ultrasound,are expanded upon from the publication on imaging and endoscopic tools in pediatric inflammatory bowel disease.

关键词： Inflammatory bowel disease Intestinal ultrasound Limberg score Hyperemia Bowel wall thickness

Optimization of the Pretreatment of the Mixture of Cassava Peelings and Pineapple Fibers Using Response Surface Methodology and a Process Simulator for the Bioethanol Production

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy and Power Engineering 2024年第2期16卷 79-96页

作者： Paul Nestor Dj.mou Dj.nga george Elambo Nkeng Madj.yogo Hervé Sirma Ahmat Tom Thierry Tchamba Tchuidj.ng Department of Textile and Leather Engineering National Advanced School of Engineering of Maroua Maroua Cameroon Department of Civil Environmental and Architectural Engineering University of Padova Padova Italy Institut du Génie des Systèmes Industriels et textiles Ecole Polytechnique de Ouagadougou Ouagadougou Burkina-Faso Department of Energy Engineering University Institute of Technology University of Ngaoundere Ngaoundere Cameroon Department of Process Engineering National Advanced School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon

The increase in oil prices and greenhouse gas emissions has led to the search for substitutes for fossil fuels. In Cameroon, the abundance of lignocellulosic resources is inherent to agricultural activity. Production of bioethanol remains a challenge given the crystallinity of cellulose and the presence of the complex. The pretreatment aimed to solubilize the lignin fraction and to make cellulose more accessible to the hydrolytic enzymes, was done using the organosolv process. A mathematical modeling was performed to point out the effect of the temperature on the kinetics of the release of the reducing sugars during the pretreatment. Two mathematical model was used, SAEMAN’s model and Response surface methodology. The first show that the kinetic parameters of the hydrolysis of the cellulose and reducing sugar are: 0.05089 min-1, 5358.1461 j.mol-1, 1383.03691 min-1, 51577.6100 j.mol-1 respectively. The second model was used. Temperature is the factor having the most positive influence whereas, ethanol concentration is not an essential factor. To release the maximum, an organosolv pre-treatment of this sub-strate should be carried out at 209.08°C for 47.60 min with an ethanol-water ratio of 24.02%. Organosolv pre-treatment is an effective process for delignification of the lignocellulosic structure.

关键词： Bioethanol Cassava Peeling Pineapple Fibers Organosolv Process and Optimization

Nitric Oxide Is Required for Homeostasis of Oxygen and Reactive Oxygen Species in Barley Roots under Aerobic Conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2014年第4期7卷 747-750页

作者： Kapuganti j. Gupta Kim H. Hebelstrup Nicholas j. Kruger R. george Ratcliffe Department of Plant Sciences University of OxfordSouth Parks RoadOxfordOX1 3RBUK Department of Molecular Biology and Genetics Aarhus UniversityForsogsvej 14200 SlagelseDenmark

Oxygen, the terminal electron acceptor for mitochondrial electron transport, is vital for plants because of its role in the production of ATP by oxidative phosphorylation. While photosynthetic oxygen production contributes to the oxygen supply in leaves, reducing the risk of oxygen limitation of mitochondrial metabolism under most conditions, root tissues often suffer oxygen deprivation during normal development due to the lack of an endogenous supply and isolation from atmospheric oxygen.

关键词： MITOCHONDRIA NO

稳定型和不稳定型心绞痛患者血清白介素-18水平的比较

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

世界核心医学期刊文摘（心脏病学分册） 2005年第7期1卷 39-39页

作者： Rosso R. Roth A. Herz I. j. george 杜缓 The Department of Cardiology Tel Aviv Sourasky Medical Center Tel Aviv Israel

Recent evidence suggests that atherosclerosis is an inflammatory disorder in which cytokines appear to play an important role. Special attention centered over the possible contribution of cytokines to the destabilization of the plaque. IL-18 is a proinflammatory cytokine of the IL-1 family, recognized for its ability to promote IFN-γsecretion. It has recently been detected in human plaques and its administration was associated with increased atheros-clerosis in apolipoprotein E(apoE) mice concomitant with an increase in plaque infiltrating inflammatory cells. In our study, we investigated whether patients with established atherosclerosis, with either stable or unstable angina, possessed high levels of IL-18. Patients with stable angina(n=48) were from the outpatient clinic whereas patients with unstable angina(n=73) were recruited upon admission and prior to performance of coronary angiography. Control patients(n=19) were healthy subj.cts with no evidence of coronary artery disease. Serum levels of IL-18 were assayed by ELISA. Patients with stable and unstable angina exhibited higher serum levels of IL-18(77.1±7.2 and 61.5±5.1 pg/ml, respectively) in comparison to control subj.cts(p=0.002 and p=0.02, respectively). However, levels of IL-18 did not differ significantly between patients with stable and unstable angina. No differences were evident in the serum concentrations of IL-18 in patients with unstable angina(n=17) upon admission and 1-3 months later when the angina was already controlled. Although IL-18 serum levels appear elevated in the presence of coronary atherosclerosis, there is no evidence to associate this progression towards plaque instability.

关键词：不稳定型心绞痛血清白介素细胞因子载脂蛋白炎症细胞浸润不稳定性健康受试者 apoE 血清浓度造影术

Evaluation of alum-based water treatment residuals used to adsorb reactive phosphorus

在线全文

学校读者我要写书评

暂无评论

Water Science and Engineering 2020年第3期13卷 181-192页

作者： george Carleton Teresa j.Cutright Department of Civil Engineering The University of AkronAkronOH 44235-3905USA

Excess reactive phosphorus(PO4)in waterways can lead to eutrophication.A low-cost approach to reducing PO4 levels in surface water was evaluated using the alum-based water treatment residual(Al-WTR)or Al-WTR augmented with powdered activated carbon(PAC-WTR).Batch adsorption-desorption and continuous flow column experiments were performed to assess the specific adsorption capacities under various concentration and flow *** Al-WTR and PAC-WTR exhibited the ability to adsorb *** overall,cumulative sorbed amount after a 28-d desorption step for Al-WTR was 33.93 mg/kg,significantly greater than the PAC-WTR value of 24.95 mg/kg(p<0.05).The continuous flow column experiments showed a theoretical PO4 uptake of 9.00 mg/g for Al-WTR and 7.14 mg/g for PAC-WTR over 720 *** surface water was used,the Al-WTR and PAC-WTR columns removed 67.4%and 62.1%of the PO4,*** results indicated that Al-WTR was more effective for in-field evaluation.

关键词： Phosphorous Alum Water treatment residuals Adsorption Desorption Powered activated carbon

The Global Energy and Water Exchanges(GEWEX)Proj.ct in Central Asia:The Case for a Regional Hydroclimate Proj.ct

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2024年第5期41卷 777-783页

作者： Michael BRODY Maksim KULIKOV Sagynbek ORUNBAEV Peter j.VAN OEVELEN International Agricultural University Tashkent 111200Uzbekistan george Mason University FairfaxVirginia 22030USA University of Central Asia Bishkek 720001Kyrgyz Republic American University of Central Asia Bishkek 720060Kyrgyz Republic International GEWEX proj.ct George Mason UniversityFairfaxVirginia 22030USA

Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Taj.kistan,Turkmenistan,and *** region’s climate is continental,mostly semi-arid to *** is a significant part of the region’s *** its nature of intensive water use,agriculture is extremely vulnerable to climate *** growth and irrigation development have significantly increased the demand for water in the *** climate change issues include melting glaciers and a shrinking snowpack,which are the foundation of the region’s water resources,and a changing precipitation *** glaciers are located in Kyrgyzstan and Taj.kistan,leading to transboundary water resource *** already has extremely high *** indicate that Central Asia has been warming and precipitation might be *** warming is expected to increase,but its spatial and temporal distribution depends upon specific global *** of future precipitation show significant uncertainties in type,amount,and *** Hydroclimate Proj.cts(RHPs)are an approach to studying these *** steps to develop an RHP began in 2021 with a widely distributed online survey about these climate *** was followed up with an online workshop and then,in 2023,an in-person workshop,held in Tashkent,*** for the Global Energy and Water Exchanges(GEWEX)proj.ct for the region include both observations and modeling,as well as development of better and additional precipitation observations,all of which are topics for the next workshop.A well-designed RHP should lead to reductions in critical climate uncertainties in policy-relevant timeframes that can influence decisions on necessary investments in climate adaptation.

关键词： GEWEX Central Asia climate change agriculture

DNA-PKcs subunits in radiosensitization by hyperthermia on hepatocellular carcinoma hepG_2 cell line

在线全文

学校读者我要写书评

暂无评论

World j.urnal of Gastroenterology 2002年第5期8卷 797-803页

作者： Walter j.Curran george Iliakis Department of Radiation Oncology of Kimmel Cancer Center Thomas Jefferson UniversityPhiladelphiaPA 19107USA

AIM: To investigate the role of DNA-PKcs subunits inradiosensitization by hyperthermia on hepatocellularcarcinoma HepG2 cell ***: Hep G2 cells were exposed to hyperthermiaand irradiation. Hyperthermia was given at 45.5 ℃Cellsurvival was determined by an in vitro clonogenic assay forthe cells treated with or without hyperthermia at varioustime points. DNA DSB rej.ining was measured usingasymmetric field inversion gel electrophoresis (AFIGE). TheDNA-PKcs activities were measured using DNA-PKcs enzymeassay ***: Hyperthermia can significantly enhanceirradiation-killing cells. Thermal enhancement ratio ascalculated at 10 % survival was 2.02. The difference inradiosensitivity between two treatment modes manifestedas a difference in the α components and the almost sameβ components, which α value was considerably higher inthe cells of combined radiation and hyperthermia ascompared with irradiating cells (1.07 Gy-1 versus 0.44 Gy1). Survival fraction showed 1 logarithm increase after an8-hour interval between heat and irradiation, whereas DNA-PKcs activity did not show any recovery. The cells wereexposed to heat 5 minutes only, DNA-PKcs activity wasinhibited at the nadir, even though the exposure time waslengthened. Whereas the ability of DNA DSB rej.ining wasinhibited with the increase of the length of hyperthermictime. The repair kinetics of DNA DSB rej.ining aftertreatment with Wortmannin is different from thehyperthermic group due to the striking high slow ***: Determination with the cell extracts andthe peptide phosphorylation assay, DNA-PKcs activity wasinactivated by heat treatment at 45.5 C, and could notrestore. Cell survival is not associated with the DNA-PKcsinactivity after heat. DNA-PKcs is not a unique factor affectingthe DNA DSB repair. This suggests that DNA-PKcs do notplay a crucial role in the enhancement of cellularradiosensitivity by hyperthermia.

关键词：肝癌放射治疗放射敏感性催化作用 DNA激酶

Understanding Performance for Two 802.11 Competing Flows

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urnal of Computer Science & Technology 2008年第3期23卷 365-376页

作者： Michael j.Feeley Brendan Cully Sharath j.george Department of Computer Science University of British ColumbiaVanconverCanada

It is well known that 802.11 suffers from both inefficiency and unfairness in the face of competition and interference. This paper provides a detailed analysis of the impact of topology and traffic type on network performance when two flows compete with each other for airspace. We consider both TCP and UDP flows and a comprehensive set of node topologies. We vary these topologies to consider all combinations of the following four node-to-node interactions：（1） nodes unable to read or sense each other, （2） nodes able to sense each other but not able to read each other＇s packets and nodes able to communicate with （3） weak and with （4） strong signal. We evaluate all possible cases through simulation and show that the cases can be reduced to 9 UDP and 10 TCP 802.11g models with similar efficiency/fairness characteristics. We also validate our simulation results with extensive experiments conducted in a laboratory testbed. These more detailed models improve on previous work such as hidden-/exposed-terminal categorization and are thus better suited as a basis for adaptive techniques to improve performance in 802.11 multi-hop WLAN or Mesh Networks.

关键词： 802.11 wireless unfairness two-flow competition network topology

Oil-bearing fluid inclusions from the Palaeoproterozoic:A review of biogeochemical results from time-capsules >2.0 Ga old

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2009年第1期52卷 1-11页

作者： Simon C. george Adriana DUTKIEWICZ Herbert VOLK j.hn RIDLEY David j. MOSSMAN Roger BUICK Department of Earth and Planetary Sciences Macquarie University School of Geosciences University of Sydney CSIRO Petroleum Department of Geosciences Colorado State University Department of Geography Mount Allison University Department of Earth and Space Sciences & Astrobiology Program University of Washington

The observation of oil inclusions trapped prior to 2.0 Ga in Palaeoproterozoic rocks and the ability to obtain detailed molecular geochemical information from them provide a robust way for understanding the early biog... 详细信息

关键词： Palaeoproterozoic fluid inclusion oil biomarker blank

Neuronal failure in Alzheimer's disease: a view through the oxidative stress looking-glass

在线全文

学校读者我要写书评

暂无评论

Neuroscience Bulletin 2014年第2期30卷 243-252页

作者： David j. Bonda Xinglong Wang Hyoung-Gon Lee Mark A. Smith george Perry Xiongwei Zhu Department of Pathology Case Western Reserve University UTSA Neurosciences Institute and Department of Biology University of Texas at San Antonio

Considerable debate and controversy surround the cause（s） of AIzheimer＇s disease （AD）. To date, several theories have gained notoriety, however none is universally accepted. In this review, we provide evidence for the oxidative stress-induced AD cascade that posits aged mitochondria as the critical origin of neurodegeneration in AD.

关键词： Alzheimer's disease amyloid-beta free radicals mitochondria mitochondrial dynamics oxidativestress