检索结果-南通市图书馆

Petroleum 2017年第1期3卷 96-108页

作者： christina Hemme Wolfgang van Berk TU Clausthal Institute of Disposal ResearchDepartment of HydrogeologyLeibnizstrasse 1038642 Clausthal-ZellerfeldGermany

Carbon capture and storage in deep geological formations is a method to reduce greenhouse gas *** CO_(2) is injected into a reservoir and dissolves in the *** the impact of pressure and temperature(P-T)the aqueous species of the CO_(2)-acidified brine diffuse through the cap rock where they trigger CO_(2)-watererock *** geochemical reactions result in mineral dissolution and precipitation along the CO_(2) migration path and are responsible for a change in porosity and therefore for the sealing capacity of the cap *** study focuses on the diffusive mass transport of CO_(2) along a gradient of decreasing PeT *** process is retraced with a one-dimensional hydrogeochemical reactive mass transport *** semigeneric hydrogeochemical model is based on chemical equilibrium *** on a broad variety of scenarios,including different initial mineralogical,chemical and physical parameters,the hydrogeochemical parameters that are most sensitive for safe long-term CO_(2) storage are *** results demonstrate that PeT conditions have the strongest effect on the change in porosity and the effect of both is stronger at high PeT conditions because the solubility of the mineral phases involved depends on PeT ***,modeling results indicate that the change in porosity depends strongly on the initial mineralogical composition of the reservoir and cap rock as well as on the brine ***,a wide range of conditions for safe CO_(2) storage is identified.

关键词： rock reservoir geochemical

Integrating insulin-like growth factor 1 and sex hormones into neuroprotection:Implications for diabetes

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Diabetes 2017年第2期8卷 45-55页

作者： Jacob Huffman christina Hoffmann George T Taylor Behavioral Neuroscience Program Department of Psychological SciencesUniversity of MissouriSt. Interfakultare Biomedizinische Forschung-seinrichtung der Universitat Heidelberg

Brain integrity and cognitive aptitude are often impaired in patients with diabetes mellitus, presumably a result of the metabolic complications inherent to the disease. However, an increasing body of evidence has demonstrated the central role of insulin-like growth factor 1(IGF1) and its relation to sex hormones in many neuroprotective processes. Both male and female patients with diabetes display abnormal IGF1 and sexhormone levels but the comparison of these fluctuations is seldom a topic of interest. It is interesting to note that both IGF1 and sex hormones have the ability to regulate phosphoinositide 3-kinase-Akt and mitogen-activated protein kinases-extracellular signal-related kinasesignaling cascades in animal and cell culture models of neuroprotection. Additionally, there is considerable evidence demonstrating the neuroprotective coupling of IGF1 and estrogen. Androgens have also been implicated in many neuroprotective processes that operate on similar signaling cascades as the estrogen-IGF1 relation. Yet, androgens have not been directly linked to the brain IGF1 system and neuroprotection. Despite the sex-specific variations in brain integrity and hormone levels observed in diabetic patients, the IGF1-sex hormone relation in neuroprotection has yet to be fully substantiated in experimental models of diabetes. Taken together, there is a clear need for the comprehensive analysis of sex differences on brain integrity of diabetic patients and the relationship between IGF1 and sex hormones that may influence brain-health outcomes. As such, this review will briefly outline the basic relation of diabetes and IGF1 and its role in neuroprotection. We will also consider the findings on sex hormones and diabetes as a basis for separately analyzing males and females to identify possible hormone-induced brain abnormalities. Finally, we will introduce the neuroprotective interplay of IGF1 and estrogen and how androgen-derived neuroprotection operates through similar si

关键词： Diabetes Androgens Estrogen Insulin Insulin-like growth factor 1 Neuroprotection Brain integrity Cognition

Contrast-enhanced ultrasound of focal liver masses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Hepatoma Research 2020年第9期6卷 10-20页

作者： Stephanie R.Wilson christina Merrill Department of Radiology University of CalgaryCalgary T2N 2T9Canada Department of Radiology Foothills Medical CentreCalgary T2N 2T9Canada.

Non-invasive imaging is the current method of choice for the characterization of frequently discovered focal liver *** historically,contrast-enhanced computed tomography(CT)and magnetic resonance(MR)scans have been selected for this purpose,contrast-enhanced ultrasound(CEUS)now offers a less expensive and safer method to acquire the same *** with the intravenous injection of a microbubble contrast agent,CEUS provides some unique advantages that make it a valuable addition to an imaging *** is performed in dynamic real-time,providing superior temporal resolution compared to other modalities and allowing detection of enhancement regardless of its timing or *** is performed with a purely intravascular contrast agent,providing accurate depiction of the presence of microbubbles in the circulation in all phases of *** compares with CT and MR contrast agents,which have a well-recognized interstitial *** discordant imaging may occur especially in the portal venous phase,when CT and MR may show pseudoenhancement from interstitial contrast,while CEUS will accurately show washout in malignant ***,the contrast specific software used to perform CEUS has an excellent subtraction technique,which produces a contrast only image with high sensitivity to enhancement in thin septations and small *** makes a positive contribution to liver mass characterization in any situation.

关键词： Contrast-enhanced ultrasound liver cancer diagnosis

Incidence and determinants of sudden infant death syndrome:a population-based study on 37 million births

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 Pediatrics 2015年第1期11卷 41-47页

作者： Ghaidaa F Hakeem Lisa Oddy christina A Holcroft Haim A Abenhaim Department of Obstetrics and Gynecology Jewish General HospitalMcGill University Center for Clinical Epidemiology and Community Studies Jewish General HospitalMontréalQuébecCanada

Background:The objective of our study is to measure the incidence of sudden infant death syndrome(SIDS),estimate the birth to death interval,and identify associated maternal and infant risk ***:We carried out a population-based cohort study on 37418280 births using data from the Centers for Disease Control and Prevention's"Linked Birth-Infant Death"and"Fetal Death"data files from 1995 to *** statistics and cox-proportional hazard models were used to estimate the adjusted effect of maternal and newborn characteristics on the risk of ***:There were 24101 cases of SIDS identified for an overall 10-year incidence of 6.4 cases per 10000 *** the study period,the incidence decreased from 8.1 to 5.6 per 10000 and appeared to be most common among infants aged 2-4 *** factors inchuded maternal age<20 years,black,non-Hispanic race,smoking,increasing parity,inadequate prenatal care,prematurity and growth ***:While the incidence of SIDS in the US has declined,it currently remains the leading cause of post-neonatal mortality,highlighting an important public health *** campaigns should be targeted towards mothers at increased risk in order to raise their awareness of modifiable risk factors for SIDS such as maternal smoking and inadequate prenatal care.

关键词： incidence risk factors sudden infant death syndrome

Liver surgery in cirrhosis and portal hypertension

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 2016年第9期22卷 2725-2735页

作者： christina Hackl Hans J Schlitt Philipp Renner Sven A Lang Department of Surgery University Medical Center Regensburg

The prevalence of hepatic cirrhosis in Europe and the United States, currently 250 patients per 100000 inhabitants, is steadily increasing. Thus, we observe a significant increase in patients with cirrhosis and portal hypertension needing liver resections for primary ormetastatic lesions. However, extended liver resections in patients with underlying hepatic cirrhosis and portal hypertension still represent a medical challenge in regard to perioperative morbidity, surgical management and postoperative outcome. The Barcelona Clinic Liver Cancer classification recommends to restrict curative liver resections for hepatocellular carcinoma in cirrhotic patients to early tumor stages in patients with Child A cirrhosis not showing portal hypertension. However, during the last two decades, relevant improvements in preoperative diagnostic, perioperative hepatologic and intensive care management as well as in surgical techniques during hepatic resections have rendered even extended liver resections in higher-degree cirrhotic patients with portal hypertension possible. However, there are few standard indications for hepatic resections in cirrhotic patients and risk stratifications have to be performed in an interdisciplinary setting for each individual patient. We here review the indications, the preoperative risk-stratifications, the morbidity and the mortality of extended resections for primary and metastatic lesions in cirrhotic livers. Furthermore, we provide a review of literature on perioperative management in cirrhotic patients needing extrahepatic abdominal surgery and an overview of surgical options in the treatment of hepatic cirrhosis.

关键词： Liver resection Hepatocellular carcinoma Liver metastases Portal hypertension Cholangiocellular carcinoma Cirrhosis

Reforming the UNSC: An Ongoing Dilemma

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Reforming the UNSC: An Ongoing Dilemma

作者： Cheryl christina Darroux 外交学院

学位级别：硕士

This study examines why reforming the United Nations Security Council （UNSC） is acrucial necessity and how that contributes to the Council’s capabilities in addressinghumanitarian crisis. We specifically focus on three major structural weaknesses–the PermanentFive （P-5） members, the veto and the principle of state sovereignty-that influence the decision-making process. In contrast to other studies, we consider whether the Council needs reform toreflect a more representative and effective peacekeeping body capable of addressing crisesarising from intra-state conflicts. We find that most proposals on Council reform calls forincrease in membership composition in both the permanent and non-permanent categories toinclude regions that are not represented in the permanent category. Using various case studies,we empirically focus on how P-5members use their position and power to pursue their nationalinterest at the expense of humanity. We demonstrate that none of the proposals recommendmembership composition in the form of regional organizations instead of the status quo neitherdoes any highlight the human aspect or the attitude of the P-5that is so very crucial for thereform process to succeed.

关键词：

EDISON-WMW: Exact Dynamic Programing Solution of the Wilcoxon–Mann–Whitney Test

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Genomics, Proteomics & Bioinformatics 2016年第1期14卷 55-61页

作者： Alexander Marx christina Backes Eckart Meese Hans-Peter Lenhof Andreas Keller Chair for Clinical Bioinformatics Medical Faculty Saarland University Department of Human Genetics Saarland University University Hospital Chair for Bioinformatics Saarland University

In many research disciplines, hypothesis tests are applied to evaluate whether findings are statistically significant or could be explained by chance. The Wilcoxon-Mann-Whitney （WMW） test is among the most popular hypothesis tests in medicine and life science to analyze if two groups of samples are equally distributed. This nonparametric statistical homogeneity test is commonly applied in molecular diagnosis. Generally, the solution of the WMW test takes a high combinatorial effort for large sample cohorts containing a significant number of ties. Hence, P value is frequently approximated by a normal distribution. We developed EDISON-WMW, a new approach to calcu- late the exact permutation of the two-tailed unpaired WMW test without any corrections required and allowing for ties. The method relies on dynamic programing to solve the combinatorial problem of the WMW test efficiently. Beyond a straightforward implementation of the algorithm, we pre- sented different optimization strategies and developed a parallel solution. Using our program, the exact P value for large cohorts containing more than 1000 samples with ties can be calculated within minutes. We demonstrate the performance of this novel approach on randomly-generated data, benchmark it against 13 other commonly-applied approaches and moreover evaluate molec- ular biomarkers for lung carcinoma and chronic obstructive pulmonary disease （COPD）. We foundthat approximated P values were generally higher than the exact solution provided by EDISON- WMW. Importantly, the algorithm can also be applied to high-throughput omics datasets, where hundreds or thousands of features are included. To provide easy access to the multi-threaded version of EDISON-WMW, a web-based solution of our algorithm is freely available at http：// ***/software/wtest/.

关键词： Wilcoxon-Mann-Whitneytest:Wilcoxon rank-sum test Dynamic programing Exact permutation Parallel optimization

Evaluating the Potential of Exporting Natural Gas in Tanzania

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evaluating the Potential of Exporting Natural Gas in Tanzani...

作者： christina GABRIEL KESSY 中国石油大学（北京）

学位级别：硕士

Recently,Tanzania has experience great volume of natural gas discoveries on its main land and its offshores *** oil and gas exploration in Tanzania is not new,the rapid pace of discoveries over the past few years has not been matched by the development of an adequate framework within which to govern this particular sector;both in the interest of Tanzania as well as the interests of international *** study aimed to evaluate the potential of exporting natural in *** this evaluation the main focus was on the future demand for natural gas and to analyse the competitiveness of exporting natural gas from Tanzania.A dynamic econometric model Partial Adjustment Model（PAM）was used to understand the natural gas demand and to forecast the demand of natural gas from year *** results showed that there is a positive relationship between natural gas consumption,urban population,and electricity consumption per ***,there exist a negative relationship between natural gas consumption and the industry output *** forecasts results were conducted into three scenarios high,base and low case scenario each case with a total estimated demand for natural gas to be 6.13 TCF,2.9 TCF and 0.789 *** natural gas supply is estimated to be 40.07 TCF（holding the assumption that 70% of the total discoveries is recoverable）.Tanzania competitive advantage strength mainly lies on the demand *** order to utilize its advantage Tanzania has to first strengthen its factor conditions and formulate the firm’s strategies and structure to win the rivals in the market.

关键词：

Detrimental role of hydrogen evolution and its temperature-dependent impact on the performance of vanadium redox flow batteries

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2019年第5期28卷 57-62页

作者： Abdulmonem Fetyan Gumaa A. El-Nagar Iver Lauermann Maike Schnucklake Jonathan Schneider christina Roth Institute for Chemistry and Biochemistry Freie Universitat BerlinTakustr.3D-14195 BerlinGermany Chemistry Department Faculty of ScienceCairo UniversityCairo 12613Egypt Helmholtz-Zentrum Berlin fur Materialien und Energie Hahn-Meitner-Platz 114109 BerlinGermany

This paper addresses the damaging role of the parasitic hydrogen evolution reaction (HER) in the negative half-cell of a vanadium redox flow battery (VRFB) on state-of-the-art carbon felt electrodes at different temperatures. It was found that increasing the temperature resulted in a better catalytic performance for both the positive and negative half-cell reactions. In addition, increasing the temperature significantly enhanced the undesired HER at the negative side. Operating the VRFB cell at higher temperature led to a decrease in the coulombic efficiency attributed to the higher hydrogen production. More pronounced hydrogen production caused an oxidation on the surface of the carb on fibers and a degradation of the electrode as indicated from scanning electron microscopy and X-ray photoelectron spectroscopy measurements. This observed degradation results in fading of the overall performance of the vanadium redox flow battery over time.

关键词： Hydrogen evolution Carbon felt Degradation Electrode Redox flow batteries

Vitreous haemorrhage as the first presentation of undiagnosed Waldenstrom macroglobulinemia

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2021年第10期14卷 1639-1641页

作者： christina S Lim Huzaifa Malick Somnath Banerjee Department of Ophthalmology University Hospitals of Leicester NHS TrustInfirmary SquareLeicester LE15WWUnited Kingdom

Dear Editor, Waldenstrom macroglobulinemia(WM) is a rare type of non-Hodgkin’s lymphoma, commonly associated with hyperviscosity syndrome. Unlike non-Hodgkin’s lymphoma, its ocular manifestations are less well described in the literature. Here we present the first case of undiagnosed WM presenting with dense vitreous haemorrhage. The study was conducted in accordance with the principles of the Declaration of Helsinki. The informed consent was obtained from the subject.

关键词： globulin lymphoma Waldenstr