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Quantitative characterization of polyacrylamide–shale interaction under various saline conditions

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Petroleum Science 2017年第3期14卷 586-596页

作者： Samyukta Koteeswaran Jack C.Pashin Josh d.Ramsey Peter E.clark School of Chemical Engineering Oklahoma State UniversityStillwater OK 74078 USA Boone Pickens School of Geology Oklahoma State University Stillwater OK 74078 USA

Interaction of polymer-containing injected fluids with shale is a widely studied phenomenon, but much is still unknown about the interaction of charged polyacrylamides such as anionic and cationic polyacrylamides with shale. The nature of interaction of charged polyacrylamides with shale is not well understood, especially from the perspective of assessing the potential for polyacrylamides to cause formation damage. Zeta potential and rheological measurements were made for Chattanooga and Pride Mountain shales suspended in polyacrylamide solutions with and without inorganic salts and tetramethyl ammonium chloride（TMAC）. The change in zeta potential and viscosity with time was recorded. The magnitude of decrease in the absolute value of zeta potential with time is indicative of adsorption of polymer on the surface of shale and serves as a measure of the extent of polymer interaction with shale. The salts that were used in this study are potassium chloride（KCl）, sodium chloride（Na Cl）. This study quantified the interaction of anionic and cationic polyacrylamide with different North American *** the experimental results, it was determined that the polyacrylamides can interact strongly with shale, particularly the cationic polyacrylamide. The objective of this study was to determine the extent of interaction of anionic and cationic polyacrylamide with each shale sample in the presence of additives such as salts.

关键词： Anionic and cationic polyacrylamides Chattanooga shale Pride Mountain shale Zeta potentialSlurry rheology

Preclinical and clinical studies on cancer-associated cachexia

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Frontiers in Biology 2018年第1期13卷 11-18页

作者： d. Brooke Widner d. clark Files Kathryn E. Weaver Yusuke Shiozawa department of Cancer Biology and Comprehensive Cancer Center Wake Forest School of Medicine Winston-Salem NC 27157 USA Internal Medicine-Sections inPulmonaryand Critical Care Medicine and Geriatrics and the Critical Illness Injury and Recovery Research Center Wake Forest School of Medicine W~nston-Salem NC 27157 USA department of Social Sciences and Health Policy and Comprehensive Cancer Center of Wake Forest University Wake Forest School of Medicine Wtnston-Salem NC 27157 USA

BACKGROUNd： Cancer cachexia is the wasting condition that is often seen in advanced stage cancer patients. This wasting is largely attributable to a systemic and progressive loss of skeletal muscle mass that greatly hinders performance of normal daily activities, resulting in reduced quality of life. Moreover, it negatively influences the prognosis of cancer patients. A general consensus in the field is that the loss of muscle mass is due both to an increase in protein degradation and a decrease in protein synthesis. Recent studies using preclinical models for studying cachexia have been useful in identifying the contribution of inflammatory cytokines （e.g. tumor necrosis factor-a and Interleukin-6）, and myostatin receptors （e.g. the type IIB activin receptor） to cachexia development, and have led to several clinical trials. However, many questions remain about the molecular mechanisms thought to play a role in the development of cachexia. METHOdS： We conducted a literature search using search engines, such as PubMed and Google Scholar to identify publications within the cancer cachexia field. RESULTS- We summarized our current knowledge of： 1） the driving mechanisms of cancer cachexia, 2） the preclinical models available for studying the condition, and 3） the findings of recent clinical trials. CONCLUSION： Cancer cachexia is a complex and variable condition that currently has no standard effective therapeutic treatment. Further studies are desperately needed to better understand this condition and develop effective combination treatments for patients.

关键词： cancer cachexia muscle wasting bodyweight loss metabolic changes increased protein degradation decreased protein synthesis

Risk of colorectal cancer in patients with diverticular disease

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World Journal of Clinical Oncology 2018年第6期9卷 119-122页

作者： jeremy Meyer Nicolas Christian Buchs Frédéric Ris division of digestive Surgery University Hospitals of Geneva

Colorectal cancer constitutes an important burden on the healthcare system. Screening at-risk populations to reduce colorectal cancer-related morbidity and mortality has become part of good clinical practice. However, recommendations regarding subgroups of patients with diverticular disease are subject to controversy. Herein, we review the most recent literature regarding the prevalence of colorectal cancer in patients with diverticular disease, diverticulitis and uncomplicated diverticulitis. The recent literature does not identify diverticular disease as a long-term risk factor for colorectal cancer. However, the risk of colorectal cancer is increased in the short-term period after hospitalization related to diverticular disease. According to a recent systematic review and meta-analysis, the prevalence of colorectal cancer is 1.6% in patients with acute diverticulitis who underwent colonoscopy. The risk of having colorectal cancer after an episode of acute diverticulitis is 44-fold higher than that of an age-and gender-adjusted reference population. despite lower among patients with uncomplicated episode, the risk of colorectal cancer remains 40-fold higher in that subpopulation than that in the reference population. To conclude, the recent literature describes an increased risk of colorectal cancer among patients with acute diverticulitis compared to the reference population. Colonoscopy is therefore recommended in patients with diverticulitis to exclude colorectal cancer.

关键词： diverticulosis diverticulitis Colonoscopy Screening Tumor Risk factor

Significance of Transients in Soil Temperature Series

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Pedosphere 2007年第6期17卷 766-775页

作者： X. ZHOU N. PERSAUd d. P. BELESKY R. B. clark department of Crop ＆ Soil Sciences The Pennsylvania State University State College Pennsylvania 16802 （USA） department of Crop ＆ Soil Environmental Sciences Virginia Polytechnic Institute and State University Blacksburg Virginia 24061 （USA） USdA//ARS//AFSRC 1224 Airport Road Beaver West Virginia 25813 （USA）

The primary objective of this study was to investigate the impact of observation scale on the estimation of soil thermal *** are usually filtered out and ignored when classical Fourier approaches are used to deconstruct and model temperature time *** was hypothesized that examination of such transients may be more important in identifying and quantifying short-term perturbations in internal soil heat transfer induced by agronomic disturbances. data-logged temperatures were collected at 10-minute intervals from thermistor probes installed at 10 and 25 cm depths in isolated areas of two grassed *** plot(6T)had been treated twice with 6 Mg ha^(-1)composted turkey litter as *** other plot(NPK)was fertilized at the same time with NPK *** methods were used to analyze the series to obtain apparent soil thermal diffusivity(d-value)at various time *** supported the hypothesis that short-term differences in internal soil heat transfer between the 6T and NPK plots were more manifest and effectively captured by estimated d-values calculated from the monthly and daily partial *** 6T plot had higher soil organic matter content than the NPK plot and had lower apparent soil thermal *** soil temperature amplitudes, required to calculate the mean d-values from partial series,were more effectively obtained using a temperature change rate *** more commonly used Fourier analysis tended to be effective for this purpose when the partial series reasonably presented well-defined diurnal patterns of increasing and decreasing temperatures.

关键词： Fourier analysis organic matter soil temperature series thermal diffusivity

Current and future applications of in vitro magnetic resonance spectroscopy in hepatobiliary disease

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World Journal of Gastroenterology 2006年第30期12卷 4773-4783页

作者： I Jane Cox Amar Sharif jeremy FL Cobbold Howard C Thomas Simon d Taylor-Robinson Imaging Sciences department Division of Clinical Sciences Imperial College London Hammersmith Hospital Campus Du Cane Road London W12 OHS United Kingdom department of Medicine Division of Medi-cine Imperial College London St Mary's Campus London W2 United Kingdom

Nuclear magnetic resonance spectroscopy allows the study of cellular biochemistry and metabolism, both in the whole body in vivo and at higher magnetic field strengths in vitro. Since the technique is non-invasive and non-selective, magnetic resonance spectroscopy methodologies have been widely applied in biochemistry and medicine. In vitro magnetic resonance spectroscopy studies of cells, body fluids and tissues have been used in medical biochemistry to investigate pathophysiologi- cal processes and more recently, the technique has been used by physicians to determine disease abnormalities in vivo. This highlighted topic illustrates the potential of in vitro magnetic resonance spectroscopy in studying the hepatobiliary system. The role of in vitro proton and phosphorus magnetic resonance spectroscopy in the study of malignant and non-malignant liver disease and bile composition studies are discussed, particularly with reference to correlative in vivo whole-body magnetic resonance spectroscopy applications. In summary, magnetic resonance spectroscopy techniques can provide non-invasive biochemical information on disease severity and pointers to underlying pathophysiological processes. Magnetic resonance spectroscopy holds potential promise as a screening tool for disease biomarkers, as well as assessing therapeutic response.

关键词： Magnetic resonance spectroscopy Liver Hepatobiliary disease Membrane metabolism

Strong, lightweight, and highly conductive CNT/Au/Cu wires from sputtering and electroplating methods

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Journal of Materials Science & Technology 2020年第5期40卷 99-106页

作者： Thang Q.Tran jeremy Kong Yoong Lee Amutha Chinnappan W.A.d.M.Jayathilaka dongxiao Ji Vishnu Vijay Kumar Seeram Ramakrishna department of Mechanical Engineering National University of Singapore9 Engineering Drive 1EA-07-05Singapore 117575Singapore

In this study, we present a 2-step deposition method via sputtering and electroplating that uses carbon nanotube(CNT) wires synthesized from a wet-spinning technique to produce high-performance CNT/Au/Cu composite wires. After the Au sputtering pre-treatment, the deposition of Cu on the CNT wires was found to be much more homogeneous due to improved wettability and reactivity of the wire surface. At different electrodeposition time, the mechanical strength of the CNT/Au/Cu composite wires could be as high as 0.74 GPa(~2 times stronger than metal wires) while their electrical conductivity could reach 4.65 × 10~5 S/cm(~80% of that for copper). More importantly, the CNT/Au/Cu composite wires with high CNT volume fraction are expected to be lightweight(up to 42% lower than Cu mass density), suggesting that our high-performance composite wires are a promising candidate to substitute conventional heavy metal wires in the future applications.

关键词： Carbon nanotube wires Sputtering Electrical conductivity Electrodeposition

Expanding plant genome-editing scope by an engineered iSpyMacCas9 system that targets A-rich PAM sequences

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Plant Communications 2021年第2期2卷 78-88页

作者： Simon Sretenovic desuo Yin Adam Levav jeremy d.Selengut Stephen M.Mount Yiping Qi department of Plant Science and Landscape Architecture University of MarylandCollege ParkMD 20742USA Hubei Academy of Agricultural Sciences Wuhan 430064China Montgomery Blair High School Silver SpringMD 20901USA Center for Bioinformatics and Computational Biology University of MarylandCollege ParkMD 20742USA department of Cell Biology and Molecular Genetics University of MarylandCollege ParkMD 20742USA Institute for Bioscience and Biotechnology Research University of MarylandRockvilleMD 20850USA

The most popular CRISPR-SpCas9 systemrecognizes canonical NGG protospacer adjacent motifs(PAMs).Previously engineered SpCas9 variants,such as Cas9-NG,favor G-rich PAMs in genome *** this manuscript,we describe a new plant genome-editing system based on a hybrid iSpyMacCas9 platform that allows for targeted mutagenesis,C to T base editing,and A to G base editing at A-rich *** study fills amajor technology gap in the CRISPR-Cas9 system for editing NAAR PAMs in plants,which greatly expands the targeting scope of ***,our vector systems are fully compatible with Gateway cloning and will work with all existing single-guide RNA expression systems,facilitating easy adoption of the systems by *** anticipate that more tools,such as prime editing,homology-directed repair,CRISPR interference,and CRISPR activation,will be further developed based on our promising iSpyMac-Cas9 platform.

关键词： plant genome editing iSpyMacCas9 PAM cytosine base editing adenine base editing

Inducible nitric oxide synthetase genotype and Helicobacter pylori infection affect gastric cancer risk

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World Journal of Gastroenterology 2012年第35期18卷 4917-4924页

作者： Alireza Rafiei Vahid Hosseini Ghasem Janbabai Bahman Fazli Abulghasem Ajami Zahra Hosseini-khah jeremy J Gilbreath d Scott Merrell Faculty of Medicine Molecular and Cell Biology Research CenterMazandaran University of Medical Sciences department of Internal Medicine Mazandaran University of Medical Sciences department of Internal Medicine Imam HospitalMazandaran University of Medical Sciences department of Microbiology and Immunology Uniformed Services University of the Health Sciences

AIM： To investigate the association of the inducible ni- tric oxide synthetase （iNOS） C150T polymorphism with Helicobacter pylori （H. pylor/） infection and gastric can- cer （GC） risk in Iran. METHOdS： In order to determine whether there was a correlation between iNOS genotype and GC in Iran, we conducted a case-control study using samples from 329 individuals. For each sample, the C150T ilVOS poly- morphism was genotyped by polymerase chain reaction （PCR） and restriction digestion. Patients were grouped by cancer presence, demographic and behavior charac- teristics, and/-/, pylori infection status. Statistical tests were conducted to determine whether any behavioral factors or a particular iNOS genotype was associated with GC in the study population. RESULTS： In this population, we found that smok- ing, hot beverage consumption, a familial history of GC and H. pylori infection status were significantly associated with GC development （P = 0.015, P 〈 0.001, P = 0.0034, and P 〈 0.015, respectively）. The distribution of the C150T ilVOS genotypes among the two study groups was not statistically significant alone, but was impacted by H. pylori infection status. When compared to the non-/-/, pylori infected group, cancer patients who had a heterozygous CT genotype and were also infected with H. pylori were 2.1 times more at risk of developing GC [odds ratio （OR） = 2.1, P = 0.03] while those with a homozygous TT genotype and infected with H. pylori were 5.0 times more at risk of developing GC （OR = 5.0, P = 0.029）. In contrast, this association was not seen in patients in the control ***： ACT or TT polymorphism at position 150 in the iNO$ gene significantly increases the risk of GC and may be a marker for GC susceptibility.

关键词： Inducible nitric oxide synthetase Gastriccancer Helicobacter pylori Heterozygous CT geno-type Homozygous -IF genotype

Synthetically engineered microbes reveal interesting principles of cooperation

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Frontiers of Chemical Science and Engineering 2017年第1期11卷 3-14页

作者： Michael d. dressier Corey J. clark Chelsea A. Thachettu Yasmine Zakaria Omar Tonsi Eldakar Robert P. Smith department of Marine Biology and Environmental Science Halmos College of Natural Sciences and Oceanography Nova Southeastern University Fort Lauderdale FL 33314-7796 USA department of Biological Sciences Halmos College of Natural Sciences and Oceanography Nova Southeastern University Fort Lauderdale FL 33314-7796 USA

Cooperation is ubiquitous in biological sys- tems. However, if natural selection favors traits that confer an advantage to one individual over another, then helping others would be paradoxical. Nevertheless, cooperation persists and is critical in maintaining homeostasis in systems ranging from populations of bacteria to groupings of mammals. developing an understanding of the dynamics and mechanisms by which cooperation operates is critical in understanding ecological and evolutionary relationships. Over the past decade, synthetic biology has emerged as a powerful tool to study social dynamics. By engineering rationally controlled and modulatable beha- vior into microbes, we have increased our overall under- standing of how cooperation enhances, or conversely constrains, populations. Furthermore, it has increased our understanding of how cooperation is maintained within populations, which may provide a useful framework to influence populations by altering cooperation. As many bacterial pathogens require cooperation to infect the host and survive, the principles developed using synthetic biology offer promise of developing novel tools and strategies to treat infections, which may reduce the use of antimicrobial agents. Overall, the use of engineered cooperative microbes has allowed the field to verify existing, and develop novel, theories that may govern cooperative behaviors at all levels of biology.

关键词： synthetic biology engineered bacteria coop-eration cheater quorum sensing