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Polymer-capped gold nanoparticles and ZnO nanorods form binary photocatalyst on cotton fabrics: Catalytic breakdown of dye

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Frontiers of materials Science 2021年第3期15卷 431-447页

作者： Bharat BARUAH christopher KELLEY Grace B.DJOKOTO Kelly m.HARTNETT Department of Chemistry and Biochemistry Kennesaw State UniversityKennesawGA 30144-5591USA Division of Natural Sciences Oglethorpe UniversityAtlantaGA 30319USA

This work reports the immobilization of zinc oxide(ZnO)nanostructures and gold nanoparticles(AuNPs)on cotton fabrics(CFs).The ZnO and AuNPs containing CF composite materials demonstrated excellent photocatalytic activity towards degradation of the model organic dye molecule.A two-step method was used to first create zinc oxide nanorods(ZnONRs)on the CF ***,these ZnONRs were decorated with cationic polymer-capped AuNPs to yield the composite materials.A one-pot synthetic route was developed to synthesize polymer-capped *** water-soluble cationic polymers used here are polyguanidino oxanorbornenes(PGONs)at 20 kDa and polyamino oxanorbornenes(PAONs)at 20 ***-vis was utilized to monitor the composite materials’photocatalytic activity in degrading model organic dye *** the materials were characterized by FTIR,UV-visible DRS,SEm,EDX,and *** composite materials exhibited excellent photocatalytic activity and recyclability in the presence of UV light.

关键词： cationic polymer polymer-capped nanoparticles ZnO nanorods fabric photocatalysis

Unanticipated multiple seam stresses from pillar systems behaving as pseudo gob–case histories

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International Journal of mining Science and Technology 2017年第1期27卷 131-137页

作者： Gauna michael mark christopher Pittsburgh Safety and Health Technology Center Mine Safety and Health Administration(MSHA)PittsburghPA 15236USA

Underground coal mining in the U.S. is conducted in numerous regions where previous workings exist above and/or below an actively mined seam. miners know that overlying or underlying fully extracted coal areas, also known as gob regions, can result in abutment stresses that affect the active mining. If there was no full extraction, and the past mining consists entirely of intact pillars, the stresses on the active seam are usually minimal. However, experience has shown that in some situations there has been sufficient yielding in overlying or underlying pillar systems to cause stress transfer to the adjoining larger pillars or barriers, which in turn, transfer significant stresses onto the workings of the active seam. In other words, the overlying or underlying pillar system behaves as a ‘‘pseudo gob." The presence of a pseudo gob is often unexpected, and the consequences can be severe. This paper presents several case histories, summarized briefly below, that illustrate pseudo gob phenomenon:(1) pillar rib degradation at a West Virginia mine at 335 m depth that contributed to a rib roll fatality,(2) pillar rib deterioration at a Western Kentucky mine at 175 m depth that required pillar size adjustment and installation of supplemental bolting,(3) roof deterioration at an eastern Kentucky mine at 400 m depth that stopped mine advance and required redirecting the section development,(4) coal burst on development at an eastern Kentucky mine at 520 m depth that had no nearby pillar recovery, and(5) coal burst on development at a West Virginia mine at the relatively shallow depth of 335 m that also had no nearby pillar recovery. The paper provides guidance so that when an operation encounters a potential pseudo gob stress interaction the hazard can be mitigated based on an understanding of the mechanism encountered.

关键词： Underground mining Coal multiple seam Gob Ground control

Plasma-catalysis: Is it just a question of scale?

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Frontiers of Chemical Science and Engineering 2019年第2期13卷 264-273页

作者： J.christopher Whitehead School of Chemistry The University of ManchesterManchester M13 9PLUK

The issues of describing and understanding the changes in performance that result when a catalyst is placed into plasma are discussed. The different chemical and physical interactions that result and how their combination might produce beneficial results for the plasma-catalytic processing of different gas streams are outlined with particular emphasis being placed on the different range of spatial and temporal scales that must be considered both in experiment and modelling. The focus is on non-thermal plasma where the lack of thermal equilibrium creates a range of temperature scales that must be considered. This contributes in part to a wide range of inhomogeneity in different properties such as species concentrations and electric fields that must be determined experimentally by in situ methods and be incorporated into modelling. It is concluded that plasmacatalysis is best regarded as conventional catalysis perturbed by the presence of a discharge, which modifies its operating conditions, properties and outcomes often in a very localised way. The sometimes used description "plasma-activated catalysis" is an apt one.

关键词： plasma catalysis plasma-activated catalysis non-thermal plasma CO2 conversion

Polyplex interaction strength as a driver of potency during cancer immunotherapy

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Nano Research 2018年第10期11卷 5642-5656页

作者： Shannon d. Tsai James I. Andorko Xiangbin Zeng Joshua m. Gammon christopher m. dewell Fischell Department of Bioengineering University of Marylond 8278 Paint Branch Drive College Park MD 20742 USA Robert E. Fischell Institute for Biomedicol Devices University of Maryland 8278 Paint Branch Drive College Park MD 20742 USA United States Department of Veterans Affairs Maryland VA Health Care System 10 North Greene Street Baltimore MD 21201 USA Deportment of microbiology and Immunology University of Maryland Medical School 685 West Baltimore Street Baltimore MD 21201 USA marlene and Stewart Greenebaum Cancer Center 22 South Greene Street Baltimore MD 21201 USA

many experimental cancer vaccines are exploring toll-like receptor agonists （TLRas） such as CpG, a DNA motif that agonizes toll-like receptor 9 （TLR9）, to trigger immune responses that are potent and molecularly-specific. The ability to tune the immune response is especially important in the immunosuppressive microenvironments of tumors. Because TLR9 is located intracellularly, CpG must be internalized by immune cells for functionality. Polyplexes can be self- assembled through electrostatics using DNA （anionic） condensed by a positively charged carrier. These structures improve cell delivery and have been widely explored for gene therapy. In contrast, here we use cationic poly （^-amino esters）（PBAEs） to assemble polyplexes from CpG as an adjuvant to target and improve immune stimulation in cells and mouse models. Polyplexes were formed over a range of PBAE：CpG ratios, resulting in a library of complexes with increasingly positive charge and stronger binding as PBAE：CpG ratio increased. Although higher PBAE：CpG ratios exhibited improved CpG uptake, lower ratios of PBAE：CpG--which condensed CpG more weakly, activated DCs and tumorspecific T cells more effectively. In a mouse melanoma model, polyplexes with lower binding affinities improved survival more effectively compared with higher binding affinities. These data demonstrate that altering the polyplex interaction strength impacts accessibility of CpG to TLRs in immune cells. Thus, physiochemical properties, particularly the interplay between charge, uptake, and affinity, play a key role in determining the nature and efficacy of the immune response generated. This insight identifies new design considerations that must be balanced for engineering effective immunotherapies and vaccines.

关键词： cancer immunotherapy nanoparticle vaccine polyplex

Analysis of new bone,cartilage,and fibrosis tissue in healing murine allografts using whole slide imaging and a new automated histomorphometric algorithm

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Bone Research 2015年第4期3卷 226-234页

作者： Longze Zhang martin Chang christopher A Beck Edward m Schwarz Brendan F Boyce Center for musculoskeletal Research School of Medicine and DentistryUniversity of Rochester Medical Center

Histomorphometric analysis of histologic sections of normal and diseased bone samples,such as healing allografts and fractures,is widely used in bone ***,the utility of traditional semi-automated methods is limited because they are labor-intensive and can have high interobserver variability depending upon the parameters being assessed,and primary data cannot be re-analyzed *** histomorphometry has long been recognized as a solution for these issues,and recently has become more feasible with the development of digital whole slide imaging and computerized image analysis systems that can interact with digital ***,we describe the development and validation of an automated application（algorithm）using Visiopharm＇s image analysis system to quantify newly formed bone,cartilage,and fibrous tissue in healing murine femoral allografts in high-quality digital images of H＆E/alcian blue-stained decalcified histologic *** validate this algorithm,we compared the results obtained independently using OsteomeasureTm and Visiopharm image analysis *** intraclass correlation coefficient between Visiopharm and Osteomeasure was very close to one for all tissue elements tested,indicating nearly perfect reproducibility across *** new algorithm represents an accurate and labor-efficient method to quantify bone,cartilage,and fibrous tissue in healing mouse allografts.

关键词： cartilage slide automated healing fibrous Figure automatically sections segmentation quantify

Release models for leaks from high-pressure hydrogen storage systems

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Chinese Science Bulletin 2014年第19期59卷 2302-2308页

作者： Xue-Fang Li David m. christopher Jing-Liang Bi Key Laboratory for Thermal Science and Power Engineering of ministry of Education Tsinghua University

Simulations and analyses of experimental data from leaks from high-pressure hydrogen storage systems will require knowledge of the stagnation state time histories and stream properties exiting the *** analytical ideal-gas model based on the ideal gas state equation and a computer program making use of the NIST standard reference database(REFPROP)were developed to model the entire process of leaks from high-pressurized hydrogen gas *** results obtained by the two methods agree with each other *** the gas behavior departs from the ideal gas properties at high pressures,the actual stagnation pressure and temperature decay more rapidly than with the ideal-gas assumption.

关键词：存储系统高压氢理想气体状态方程泄漏释放模式理想气体模型计算机程序时间历程

Bulk petroleum geochemistry of shales from the onshore Rio del Rey Basin,Cameroon

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Energy Geoscience 2022年第2期3卷 111-119页

作者： christopher m.Agyingi Noel C.Tangko Emmanuel Eseme Department of Geology University of BueaCameroon P.O.Box 63BueaCameroon Activation Laboratories Ltd AncasterONCanada

Petroleum production in the Rio del Rey Basin,which is an extension of the Niger Delta of Nigeria into Cameroon,has been limited to the Tertiary offshore portion since the late *** to dedlining reserves in this offshore portion,the onshore Cretaceous portion of the basin attracted significant attention in the last *** the present *** from outcrops in the onshore portion of the basin were analyzed to evaluate their potential as source rocks,assess hydrocarbon generation,and highlight their signifcance for *** observations,total organic carbon(TOC)measure-ments,and Rock Eval pyrolysis were used to generate data for these ***-eval S2 values(0.42-3 mg HC/g rock)based on measured present-day TOC values(0.58-2.44 wtx)of the shales studied signify poor to fair source rock potentials,whereas calculated S2 values(1.74-8.19 mg HC/g rock)based on estimated original TOC values(0.67-2.87 wt%)produced fair to good source rocks containing Type Ⅱ/Ⅲ kerogen,which were transformed by maturity to the present-day Type Ⅲ/Ⅳ *** of the samples based on Tmax values varying between 439 and 471℃are equivalent to maturity values ranging between 0.74% R_(r) and 1.32% R_(r), and these represent the peak oil to condensate/wet gas zones of hy-drocarbon *** results demonstrate that mature source rocks are present in the onshore part of the Rio del Rey Basin,and thus,it is suitable for petroleum exploration.

关键词： Shale Rio del Rey Basin Total organic carbon Rock-eval Petroleum geochemistry Cameroon

The ASD that Wouldn’t Go Away:An Unusual Case of ASD Device Failure in a Patient with marfan Syndrome

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Congenital Heart Disease 2021年第2期16卷 183-187页

作者： christopher m.Day Neda mulla Timothy martens Brent m.Gordon Department of Pediatrics Loma Linda University Medical CenterLoma LindaCA 92354USA Division of Pediatric Cardiology Loma Linda University Medical CenterLoma LindaCA 92354USA Division of Cardiothoracic Surgery Loma Linda University Medical CenterLoma LindaCA 92354USA

marfan syndrome patients have connective tissue abnormalities that predispose them to intracardiac defects and postoperative *** present a case of late onset ASD device failure secondary to device movement within the atrial septum in a girl with marfan *** case study suggests that further studies are necessary to determine the optimal device and approach for ASD repair in this patient cohort.

关键词： Congenital heart disease atrial septal defect device closure connective tissue disease marfan syndrome transcatheter intervention

Hypothesized summative anal physiology score correlates but poorly predicts incontinence severity

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World Journal of Gastroenterology 2017年第31期23卷 5732-5738页

作者： christopher J Young Assad Zahid Cherry E Koh Jane m Young Department of Colorectal Surgery University of Sydney RPAH medical Centre Discipline of Surgery University of Sydney Surgical Outcome Research Centre(SOu RCe) Royal Prince Alfred HospitalUniversity of Sydney School of Public health University of Sydney

To explore the relationship between such a construct and an existing continence score. mETHODSA retrospective study of incontinent patients who underwent anal physiology (AP) was performed. AP results and Cleveland Clinic Continence Scores (CCCS) were extracted. An anal physiology score (APS) was developed using maximum resting pressures (mRP), anal canal length (ACL), internal and external sphincter defects and pudendal terminal motor latency. Univariate associations between each variable, APS and CCCS were assessed. multiple regression analyses were performed. RESULTSOf 508 (419 women) patients, 311 had both APS and CCCS measured. Average mRP was 51 mmHg (SD 23.2 mmHg) for men and 39 mmHg (19.2 mmHg) for women. Functional ACL was 1.7 cm for men and 0.7 cm for women. Univariate analyses demonstrated significant associations between CCCS and mRP (P = 0.0002), ACL (P = 0.0006) and pudendal neuropathy (P multiple regression showed that the variables most useful in predicting CCCS were external sphincter defect, pudendal neuropathy and previous pelvic surgery, but only improving the scores predictive ability to 12.5%. CONCLUSIONThis study shows that the ability of AP tests to predict continence scores improves when considered collectively, but that a constructed summation model before and after multiple regression is poor at predicting the variability in continence scores.

关键词： Incontinence Anal physiology Anal canal Anal ultrasound manometry Electromyography