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Whole-mine subsidence over tabular deposits and related seismicity

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International Journal of Mining Science and Technology 2017年第1期27卷 171-177页

作者： Pariseau William g. McCarterr michael K. Department of Mining Engineering University of UtahSalt Lake CityUTUSA

The challenge of estimating mine-wide subsidence and linkages to seismicity over tabular deposits is addressed by a special finite element technique(dual node–dual mesh). Subsidence and mine-induced seismicity begins near the face when caving occurs and propagates to the surface as extraction reaches a critical extent. Thus, the challenge is to obtain details at the face at the meter scale and also at the surface over the whole mine at the kilometer scale. Interactions between old and new sections of a mine are automatically taken into account with this technique. The finite element method is well established technology based on fundamentals of physical laws, kinematics and material laws. With this technique, no empirical ‘‘scaling" or fitting computer output by input data ‘‘adjustment" to mine measurements is necessary. Capability is demonstrated for doing practical whole-mine subsidence analysis from first principles. Mine-induced seismicity is shown to correlate well with face advance and element failure.

关键词： Whole mine subsidence Multi-scale Finite element analysis Mine induced seismicity

The acceleration of a high-charge electron bunch to 10 geV in a 10-cm nanoparticle-assisted wakefield accelerator

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Matter and Radiation at Extremes 2024年第1期9卷 15-24页

作者： Constantin Aniculaesei Thanh Ha Samuel Yoffe Lance Labun Stephen Milton Edward McCary michael M.Spinks Hernan J.Quevedo Ou Z.Labun Ritwik Sain Andrea Hannasch Rafal Zgadzaj Isabella Pagano Jose A.Franco-Altamirano Martin L.Ringuette Erhart gaul Scott V.Luedtke ganesh Tiwari Bernhard Ersfeld Enrico Brunetti Hartmut Ruhl Todd Ditmire Sandra Bruce michael E.Donovan michael C.Downer Dino A.Jaroszynski Bjorn Manuel Hegelich University of Texas at Austin AustinTexas 78712USA SUPA Department of Physics University of StrathclydeGlasgowScotland G4 ONGUnited Kingdom Tau Systems Inc.AustinTexas 78701USA Lawrence Livermore National Laboratory LivermoreCalifornia 94550USA Los Alamos National Laboratory Los AlamosNew Mexico 87545USA Brookhaven National Laboratory UptonNew York 11973USA Ludwig-Maximilians-Universität MunichGermany

An intense laser pulse focused onto a plasma can excite nonlinear plasma *** appropriate conditions,electrons from the background plasma are trapped in the plasma wave and accelerated to ultra-relativistic *** scheme is called a laser wakefield *** this work,we present results from a laser wakefield acceleration experiment using a petawatt-class laser to excite the wakefields as well as nanoparticles to assist the injection of electrons into the accelerating phase of the *** find that a 10-cm-long,nanoparticle-assisted laser wakefield accelerator can generate 340 pC,10±1.86 geV electron bunches with a 3.4 geV rms convolved energy spread and a 0.9 mrad rms *** can also produce bunches with lower energies in the 4–6 geV range.

关键词： acceleration nanoparticle charge

Disorders of potassium homeostasis after kidney transplantation

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World Journal of Transplantation 2024年第3期14卷 40-51页

作者： Abdelhamid Aboghanem g V Ramesh Prasad School of Medicine University of TorontoToronto M5C 2T2OntarioCanada Kidney Transplant Program St.Michael's HospitalToronto M5C 2T2OntarioCanada

Disturbances of potassium balance are often encountered when managing kidney transplant recipients(KTR).Both hyperkalemia and hypokalemia may present either as medical emergencies or chronic outpatient *** the high incidence of hyperkalemia and its potential life-threatening implications,consensus on its management in KTR is *** in KTR is also well-described,although it is given less attention by clinicians compared to *** article discusses the etiology,pathophysiology and management of both types of potassium disorders in *** any emergent situation has been corrected,treatment approaches include correcting insulin deficiency if present,adjusting non-immunosuppressive and immunosuppressive medications,elimi-nating or supplementing potassium as needed,and dietary *** commonly of multifactorial etiology,ascertaining the specific cause in a particular patient will help guide successful *** KTR through regular laboratory testing is essential to detect serious disturbances in potassium balance since patients are often asymptomatic.

关键词： Balance Dialysis Hyperkalemia Hypokalemia Kidney Metabolism Potassium

Remifentanil mimics cardioprotective effect of ischemic preconditioning via protein kinase C activation in open chest of rats

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Acta Pharmacologica Sinica 2005年第5期26卷 546-550页

作者： michael g IRWIN Tak-ming WONg Department of Anesthesiology Department of Physiology the University of Hong Kong Hong Kong China

Aim:To examine whether the protective effect of remifentanil preconditioning（RPC）on postischemic hearts is mediated by protein kinase（PKC）activation incomparison with ischemic preconditioning（IPC）.Methods:Male Sprague-Dawleyrats were anesthetized and their chests were *** experiment was per-formed with chelerythrine（CHE,2mg/kg）,gF109203X（0.05 mg/kg）protein kinaseC（PKC）inhibitors administered before RPC(remifentanil 6μ***-1·min-1×3 cycle)orIPC,*** size（IS）,as a percentage of the area at risk（AAR）,wasdetermined by triphenyltetrazolium ***:In groups subjected to IPCand RPC the IS/AAR were significantly reduced（IS/AAR from 52.7%±5.5% to12.9%±3.4%,PgF,both PKC inhibitors,administered 5 min before RPC or IPC completelyabolished the cardioprotective effect of RPC（IS/AAR:CHE+RPC 51.2%±5.0%,gF+RPC 53.6%±6.1%,P>0.05 vs CON）or IPC（CHE+IPC 53.7%±4.3%,gF+IPC54.1%±6.2%,P>0.05 vs CON）.The difference was not significant in any of thehemodynamic parameters between control and treatment groups during ischemiaand ***:Remifentanil confers myocardial protection againstischemic injury through a mechanism that is similar to IPC and involves PKCactivation.

关键词： remifentanil myocardial ischemia preconditioning myocardial reperfusion injury protein kinase C chelerythrine gF109203X

Survival and clinical outcomes in patients with metastatic epidural spinal cord compression after spinal surgery:a prospective,multicenter,observational cohort study

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Chinese Journal of Cancer 2016年第4期35卷 157-159页

作者： Anick Nater michael g.Fehlings Department of Surgery Division of NeurosurgeryUniversity of Toronto Division of Neurosurgery Toronto Western HospitalUniversity Health Network

Background:High quality studies have been challenging to undertake in patients with metastatic epidural spinal cord ***,in the article "Survival and Clinical Outcomes in Surgically Treated Patients With Metastatic Epidural Spinal Cord Compression:Results of the Prospective Multicenter AOSpine Study" recently published in the Journal of Clinical Oncology,our team provided convincing evidence that spinal surgery improves overall quality of life in patients with this potentially devastating complication of *** that metastatic spinal lesions treated with surgery have the highest mean cost among all oncological musculo-skeletal issues,it is essential to provide high quality data to optimize the therapeutic approaches and cost-effective use of health care *** body:Although the AOSpine Study provided high quality prospective data,it was primarily limited by the lack of non-operative controls and the relatively small sample *** the dearth of medical equipoise and the fundamental difference between patients deemed to be adequate surgical candidates and those who are not amenable to operative intervention,conducting a randomized controlled trial in this patient population was not felt to be ethically or medically ***,the optimal option to overcome limitations of both the lack of controls and the relatively small sample size is through collection of large prospective datasets through rigorously developed and maintained ***:With the alarming increase in the incidence of cancer in China and China's parallel growing cancer control efforts,China would offer a fantastic platform to set up a national metastatic spinal lesion *** registry would not only enhance metastatic epidural spinal cord compression translational research but also optimize patient care.

关键词： Metastatic epidural spinal cord compression Prospective study Cohort study Surgery Clinical outcomes

gene Expression Versus Sequence for Predicting Function: glia Maturation Factor gamma Is Not A glia Maturation Factor

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genomics, Proteomics & Bioinformatics 2003年第1期1卷 52-57页

作者： michael g.Walker Incyte genomics Inc. CA 94087 USA

It is standard practice, whenever a researcher finds a new gene, to search databases for genes that have a similar sequence. It is not standard practice, whenever a researcher finds a new gene, to search for genes that have similar expression (co-expression). Failure to perform co-expression searches has lead to incorrect conclusions about the likely function of new genes, and has lead to wasted laboratory attempts to confirm functions incorrectly predicted. We present here the example of glia Maturation Factor gamma (gMF-gamma). Despite its name, it has not been shown to participate in glia maturation. It is a gene of unknown function that is similar in sequence to gMF-beta. The sequence homology and chromosomal location led to an unsuccessful search for gMF-gamma mutations in glioma. We examined gMF-gamma expression in 1432 human cDNA libraries. Highest expression occurs in phagocytic, antigen-presenting and other hematopoietic cells. We found gMF-gamma mRNA in almost every tissue examined, with expression in nervous tissue no higher than in any other tissue. Our evidence indicates that gMF-gamma participates in phagocytosis in antigen presenting cells. Searches for genes with similar sequences should be supplemented with searches for genes with similar expression to avoid incorrect predictions.

关键词： gene function prediction expression analysis sequence analysis gMF-gamma

56 Years of the Marburg Virus—A Review of Therapeutics

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Open Journal of Epidemiology 2024年第2期14卷 273-283页

作者： michael M. Toza Emmanuel Imangolwa Natalia Shakela Ferdinand Ndubi Hanzoma Hatwiko Christabel N. Hikaambo Department of Pharmacy School of Health Sciences University of Zambia Lusaka Zambia Department of Biology Chemistry and Physics School of Health and Applied Sciences Namibia University of Science and Technology Windhoek Namibia Department of Pharmaceutical Chemistry and Pharmaceutics School of Pharmacy Kabarak University Nakuru Kenya Department of Physiological Sciences School of Medicine and Health Sciences Mulungushi University Livingstone Zambia

Background: The Marburg virus (MARV) is the causative agent of Marburg virus disease (MVD). This filovirus first appeared in 1967 and has since caused several outbreaks with case fatality rates between 23% and 90%. The earliest cases of MVD are thought to be caused by exposure to an infected animal, either a reservoir host (some bat species, e.g., Rousettus aegyptiacus) or a spill-over host, such as non-human primates. The virus is spread between people by direct contact with blood or other bodily fluids (including saliva, sweat, faeces, urine, tears, and breast milk) from infected individuals. Despite the high fatality rate, the Marburg virus has no vaccine or drug treatment. Recent outbreaks of the virus in 2023 in Tanzania and Equatorial guinea have reignited the need to develop effective therapeutics, especially in the wake of the COVID-19 pandemic. Purpose: This review seeks to highlight the drug discovery efforts aimed at developing vaccines or possible treatments as potential therapeutics. Several existing antiviral agents are being probed, and vaccines are in pre-clinical and clinical stages. Natural products are also an important source of possible drugs or lead compounds and when coupled with computational techniques, these strategies offer possible therapeutics for the Marburg virus, especially in Africa, which has a high disease burden. Methods: Using the search engines google Scholar and PubMed;keywords e.g. Marburg virus, Marburg treatments, Marburg virus drug discovery were utilized. Several results were yielded, and articles published in recent years were accepted into the final *** and Conclusion: This study shows there is a growing interest in therapeutics for the Marburg virus, especially with the recent outbreaks and pandemic preparedness. Initiatives that to support vaccine development and access like the MARVAC consort time are critical to fighting this public health threat.

关键词： Marburg Virus Vaccines Antivirals Viruses Drug Discovery

Peripancreatic collections in acute pancreatitis: Correlation between computerized tomography and operative fi ndings

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World Journal of gastroenterology 2010年第34期16卷 4291-4296页

作者： Santhi Swaroop Vege Joel g Fletcher Rupjyoti Talukdar michael g Sarr Miles and Shirley Fiterman Center for Digestive Diseases Rochester MN 55905 United States Department of Radiology Mayo Clinic Rochester MN 55905 United States Department of Surgery Mayo Clinic Rochester MN 55905 United States

AIM: To evaluate the ability of contrast-enhanced computerized tomography (CECT) to characterize the nature of peripancreatic ***: Twenty five patients with peripancreatic collections on CECT and who underwent operative intervention for severe acute pancreatitis were retrospectively studied. The collections were classified into (1) necrosis without frank pus; (2) necrosis with pus; and (3) fluid without necrosis. A blinded radiologist assessed the preoperative CTs of each patient for necrosis and peripancreatic fluid collections. Peripancreatic collections were described in terms of volume, location, number, heterogeneity, fluid attenuation, wall perceptibility, wall enhancement, presence of extraluminal gas, and vascular ***: Fifty-four collections were identif ied at operation, of which 45 (83%) were identif ied on CECT. Of these, 25/26 (96%) had necrosis without pus, 16/19 (84%) had necrosis with pus, and 4/9 (44%) had fluid without necrosis. Among the study characteristics, fluid heterogeneity was seen in a greater proportion of collections in the group with necrosis and pus, compared to the other two groups (94% vs 48% and 25%, P = 0.002 and 0.003, respectively). Among the wall characteristics, irregularity was seen in a greater proportion of collections in the groups with necrosis with and without pus, when compared to the group with fluid without necrosis (88% and 71% vs 25%, P = 0.06 and P geneity and presence of extraluminal gas had a specif icity and positive likelihood ratio of 92% and 5.9, respectively, in detecting pus. CONCLUSION: Most of the peripancreatic collections seen on CECT in patients with severe acute pancreatitis who require operative intervention contain necrotic tissue. CECT has a somewhat limited role in differentiating the different types of collections.

关键词： Contrastenhanced computerized tomogra-phy Correlation Pancreatic necrosis Pancreatitis Peripancreatic fluid collection Surgery

Epigenetic Repression of Male gametophyte- Specific genes in the Arabidopsis Sporophyte

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Molecular Plant 2013年第4期6卷 1176-1186页

作者： Robert D. Hoffmann michael g. Palmgren Centre for Membrane Pumps in Cells and Disease--PUMPKIN Danish National Research Foundation Department of Plant and Environmental SciencesUniversity of Copenhagen Thorvaldsensvej 40 DK-1871 Frederiksberg Denmark

Tissue formation, the identity of cells, and the functions they fulfill, are results of gene regulation. The male gametophyte of plants, pollen, is outstanding in this respect as several hundred genes expressed in pollen are not expressed in the sporophyte. How pollen-specific genes are down-regulated in the sporophyte has yet to be established. In this study, we have performed a bioinformatics analysis of publicly available genome-wide epigenetics data of sev- eral sporophytic tissues. By combining this analysis with DNase ! footprinting data, we assessed means by which the repression of pollen-specific genes in the Arabidopsis sporophyte is conferred. Our findings show that, in seedlings, the majority of pollen-specific genes are associated with histone-3 marked by mono- or trimethylation of Lys-27 （H3K27me1/ H3K27me3）, both of which are repressive markers for gene expression in the sporophyte. Analysis of DNase footprint profiles of pollen-specific genes in the sporophyte displayed closed chromatin proximal to the start codon. We describe a model of two-staged gene regulation in which a lack of nucleosome-free regions in promoters and histone modifications in open reading frames repress pollen-specific genes in the sporophyte.

关键词： male gametophyte epigenetics gene repression DNase I footprinting transcription factors bioinformatics.