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Paediatric and adult colonic manometry: A tool to help unravel the pathophysiology of constipation

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World Journal of Gastroenterology 2010年第41期16卷 5162-5172页

作者： Philip G Dinning Marc A Benninga Bridget R southwell s.mark scott Department of Gastroenterology St George Hospital University of New South Wales Kogarah Sydney 2217 Australia Department of Pediatric Gastroenterology and Nutrition Emma Children's Hospital/AMC Amsterdam 1105 AZ The Netherlands Murdoch Childrens Research Institute Royal Children's Hospital Parkville Melbourne 3052 Australia Department of Paediatrics University of Melbourne Melbourne 3052 Australia Queen Mary University London Barts and the London School of Medicine and Dentistry London E11BB United Kingdom

Colonic motility subserves large bowel functions, including absorption, storage, propulsion and defaecation. Co-lonic motor dysfunction remains the leading hypothesis to explain symptom generation in chronic constipation, a heterogeneous condition which is extremely prevalent in the general population, and has huge socioeconomic impact and individual suffering. Physiological testing plays a crucial role in patient management, as it is now accepted that symptom-based assessment, although im-portant, is unsatisfactory as the sole means of directing therapy. Colonic manometry provides a direct method for studying motor activities of the large bowel, and this review provides a contemporary understanding of how this technique has enhanced our knowledge of normalcolonic motor physiology, as well as helping to elucidate pathophysiological mechanisms underlying constipation. Methodological approaches, including available catheter types, placement technique and recording protocols, are covered, along with a detailed description of re-corded colonic motor activities. This review also criti-cally examines the role of colonic manometry in current clinical practice, and how manometric assessment may aid diagnosis, classification and guide therapeutic inter-vention in the constipated individual. Most importantly, this review considers both adult and paediatric patients. Limitations of the procedure and a look to the future are also addressed.

关键词： Colon Constipation Manometry Paediatric Adult

An in situ monitoring campaign of a hard rock pillar at great depth within a Canadian mine

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第3期12卷 427-448页

作者： Bradley Forbes Nicholas Vlachopoulos.mark s.Diederichs Andrew J.Hyett Allan Punkkinen Department of Geological sciences and Geological Engineering Queen’s UniversityKingstonOntarioK7L 3N6Canada Department of Civil Engineering Royal Military College of CanadaKingstonOntarioK7K 7B4Canada YieldPoint Inc. KingstonOntarioK7M 4W9Canada Normet Canada Ltd. LivelyOntarioP3Y 0B3Canada

A recent research campaign at a Canadian nickel-copper mine involved instrumenting a hard rock sill drift pillar with an array of multi-point rod extensometers,distributed optical fibre strain sensors,and borehole pressure cells(BHPCs).The instrumentation spanned across a 15.24 m lengthwise segment of the relatively massive granitic pillar situated at a depth of 2.44 km within the *** May 2016 and March 2017,the pillar’s displacement and pressure response were measured and correlated with mining activities on the same level as the pillar,including:(1)mine-by of the pillar,(2)footwall drift development,and(3)ore body stoping *** displacements of the pillar,the extensometers provided high temporal resolution(logged hourly)and the optical fibre strain sensors provide high spatial resolution(measured every 0.65 mm along the length of each sensor).The combination of sensing techniques allowed centimetre-scale rock mass bulking near the pillar sidewalls to be distinguished from microstrain-scale fracturing towards the core of the ***,the influence and extent of a mine-scale schistose shear zone transecting the pillar was *** converting measured rock mass displacement to velocity,a process was demonstrated which allowed mining activities inducing displacements to be categorised by time-duration and cumulative *** over half of the analysed mining activities,displacements were determined to prolong for over an hour,predominately resulting in submillimetre cumulative displacements,but in some cases multi-centimetre cumulative displacements were *** time-dependent behaviour was more pronounced within the vicinity of the plumb shear *** measurements were also used to assess selected support member load and elongation mobilisation per mining *** was found that a combined static load and elongation capacity of reinforcing members was essential to maintaining excavation stability,while

关键词： Hard rock pillar Rockburst Rock mass bulking Distributed optical fibre strain sensing Extensometer In situ monitoring High stress Dynamic support

Preventing roof fall fatalities during pillar recovery:A ground control success story

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International Journal of Mining science and Technology 2017年第1期27卷 107-113页

作者： mark Christopher Gauna Michael MsHA Pittsburgh Safety and Health Technology CenterPittsburghPA 15236USA

For decades, pillar recovery accounted for a quarter of all roof fall fatalities in underground coal *** showed that a miner on a pillar recovery section was at least three times more likely to be killed by a roof fall than other coal miners. since 2007, however, there has been just one fatal roof fall on a pillar line. This paper describes the process that resulted in this historic achievement. It covers both the key research findings and the ways in which those insights, beginning in the early 2000 s, were implemented in mining practice. One key finding was that safe pillar recovery requires both global and local *** stability is addressed primarily through proper pillar design, and became a major focus after the2007 Crandall Canyon mine disaster. But the most significant improvements resulted from detailed studies that showed that local stability, defined as roof control in the immediate work area, could be achieved with three interventions:(1) leaving an engineered final stump, rather than extracting the entire pillar,(2) enhancing roof bolt support, particularly in intersections, and(3) increasing the use of mobile roof supports(MRs). A final component was an emphasis on better management of pillar recovery *** included a focus on worker positioning, as well as on the pillar and lift sequences, MRs operations,and hazard identification. As retreat mines have incorporated these elements into their roof control plans,it has become clear that pillar recovery is not ‘‘inherently unsafe." The paper concludes with a discussion of the challenges that remain, including the problems of rib falls and coal bursts.

关键词： Retreat mining Roof support Room-and-pillar Ground control

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

Differentially expressed genes in hepatocellular carcinoma induced by woodchuck hepatitis B virus in mice

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World Journal of Gastroenterology 2001年第4期7卷 575-578页

作者： mark Feitelson Department of Pathology Second Military Medical UniversityShanghai 200433China

INTRODUCTIONHepatocellular carcinoma(HCC)is one of the major causes of death in the *** mechanism of carcinogenesis is unknown,although it is widely accepted that HBV and HCV are clsely related to liver cancer[1-5[1-5].Previously,a variety of studies have described the differences in gene expression which distinguished tumor from nontumor[6-11].Cloning of the genes,especially the genes associated with HBV and HCV,is still very important to account for the development of liver cancer.

关键词： Animals Carcinoma, Hepatocellular Cloning, Molecular DNA, Complementary Databases, Nucleic Acid Gene Expression Regulation, Neoplastic Gene Expression Regulation, Viral Hepatitis B Hepatitis B Virus, Woodchuck Humans Mice Polymerase Chain Reaction Research support, Non-U.s. Gov't

Assessing support alternatives for longwall gateroads subject to changing stress

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International Journal of Mining science and Technology 2021年第1期31卷 103-110页

作者： Gabriel s.Esterhuizen I.Berk Tulu Dave F.Gearhart Heather Dougherty mark Van Dyke National Institute for Occupational safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA West Virginia University MorgantownWV 26506USA

Longwall gateroad entries are subject to changing horizontal and vertical stress induced by redistribution of loads around the extracted *** stress changes can result in significant deformation of the entries that may include roof sag,rib dilation,and floor *** operators install different types of supports to control the ground response and maintain safe access and ventilation of the longwall *** paper describes recent research aimed at quantifying the effect of longwall-induced stress changes on ground stability and using the information to assess support *** research included monitoring of ground and support interaction at several operating longwall mines in the U.s.,analysis and calibration of numerical models that adequately represent the bedded rock mass,and observation of the support systems and their response to changes in *** models were then used to investigate the impact of geology and stress conditions on ground deformation and support response for various depths of cover and geologic *** research results were summarized in two regression equations that can be used to estimate the likely roof deformation and height of roof yield due to longwall-induced stress *** information is then used to assess the ability of support systems to maintain the stability of the *** application of the method is demonstrated with a retrospective analysis of the support performance at an operating longwall mine that experienced a headgate roof *** method is shown to produce realistic estimates of gateroad entry stability and support performance,allowing alternative support systems to be assessed during the design and planning stage of longwall operations.

关键词： Longwall Gateroad support design Coal standing support

Preventing aggressive prostate cancer with proven ：ardiovascular disease preventive methods

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Asian Journal of Andrology 2015年第6期17卷 874-877页

作者： mark A Moyad Department of Urology University of MichiganMedical Center 1500 East Medical Center DriveAnn Arbor MI 48109 USA

Cardiovascular disease （CVD） has been the number one cause of death in the U.s. for 114 of the last 115 years. Risk factors for prostate cancer have primarily mirrored risk proven risk factors for CVD, especially aggressive disease. Obesity, dyslipidemia, glucose intolerance, metabolic syndrome, unhealthy dietary habits or caloric excess, lack of physical activity, and inflammation are just some of these shared risk factors. The evidence also suggests proven CVD preventive measures are identical to prostate cancer preventive measures, especially in regard to aggressive disease. Thus, apart from lifestyle measures that can encourage optimal heart and prostate health there are potentially several dietary supplements that need to be avoided in healthy men because they may also increase the risk of prostate cancer. However, there are also several low-cost, generic, safe in the appropriate individuals, and naturally derived agents that could reduce prostate cancer risk, and these can be discussed and remembered utilizing the acronym s.A.M. （statins, aspirin, and/or metformin）.

关键词： Preventing aggressive methods

CFD based extraction column design-Chances and challenges

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Chinese Journal of Chemical Engineering 2016年第2期24卷 259-263页

作者： mark W.Hlawitschka Menwer M.Attarakilh samer s.Alzyod Hans-Jorg Bart Chair of separation science and Technology POB 3049TU KaiserslauternKaiserslautern 67653Germany Center for Computational and Mathematical Modelling(CM2) TU KaiserslauternKaiserslautern 67653Germany University of Jordan Department of Chemical Engineering11942 AmmanJordan

This paper shows that one-dimensional （I-D） [and three-dimensional （3-D） computational fluid dynamics （CFD）] simulations can replace the state-of-the-art usage of pseudo-homogeneous dispersion or back mixing models. This is based on standardized lab-scale cell experiments for the determination of droplet rise, breakage, coalescence and mass transfer parameters in addition to a limited number of additional mini-plant experiments with original fluids. Alternatively, the hydrodynamic parameters can also be derived using more sophisticated 3- D CFD simulations. Computational 1-D modeling served as a basis to replace pilot-plant experiments in any column geometry. The combination of 3-D CFD simulations with droplet population balance models （DPBM） increased the accuracy of the hydrodynamic simulations and gave information about the local droplet size. The high computational costs can be reduced by open source CFD codes when using a flexible mesh generation. First combined simulations using a three way coupled CFD/DPBM/mass-transfer solver pave the way for a safer design of industrial-sized columns, where no correlations are available.

关键词： CFD DPBM Column design

Genetic variation and potential coinfection of Wolbachia among widespread Asian citrus psyllid (Diaphorina citri Kuwayama) populations

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Insect science 2019年第4期26卷 671-682页

作者： Chia-Ching Chu mark Hoffmann W. Evan Braswell Kirsten s. Pelz-stelinski Department of Entomology and Nematology University of Florida Gainesville Florida USA Citrus Research and Education Center University of Florida Lake Alfred Florida USA 3Department of Horticultural sciences North Carolina State University Raleigh North Carolina USA Center for Plant Health science and Technology USDA APHIS Edinburg Texas USA

Wolbachia can profoundly influence the survival, reproduction, and defenses of insect hosts. These interactions could potentially be harnessed for managing pests or insecttransmitted diseases. Diaphorina citri Kuwayama is a phloem-feeding pest capable of transmitting the putative causal agent of citrus greening, Candidatus Liberibacter asiaticus (CLas). Like many insects, D. citri is also infected with Wolbachia (wDi). Recent studies indicate that the relative abundance of wDi could be associated with the abundance of CLas, and that wDi may contribute to regulating expression of phage lytic cycle genes in CLas, suggesting the need for better understanding of wDi biology in general. This study investigated the genetic diversity of wDi among D. citri in populations spanning eleven countries and two U.s. territories. six Wolbachia genes, wsp, ***, gatB, and hep A, were sequenced and compared across samples. Two prevalent wDi strains were identified across the samples, and screening of clone libraries revealed possible coinfection of wDi strains in specific populations. D. citri mitochondrial cytochrome oxidase subunit I gene (mtCOI) were more divergent between D. citri populations that were infected with different wDi strains or had different infection statuses (single infection vs. coinfection). While we could not eliminate the possibility that maternal transmission may contribute to such patterns, it is also possible that wDi may induce cytoplasmic incompatibility in their host. These fin dings should contribute to the understanding of wDi population ecology, which may facilitate manipulation of this endosymbiont for management of citrus greening disease worldwide.

关键词： bacteria genetic diversity Huanglongbing plant disease superinfection vertically transmitted endosymbionts