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Cockroach as the Earliest Eusocial Animal

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 793-808页

作者： peter VRSANSKY Geological Institute Slovak Academy of SciencesBratislavaSlovakia Russian Academy of Sciences MoscowRussia

A completely preserved cockroach Socialaperlucida gen. et sp. nov. （Blattida： Socialidae faro. nov.） is described from the Mesozoic （Albian Early Cretaceous） amber of Archingeay in France. It is categorized within the new family Socialidae, originating from the Mesozoic cockroach family Liberiblattinidae, and representing the sister group to the most basal known eutermite families. Numerous direct and indirect morphological evidence （such as a unique narrow body and pronotum with reduced coloration, legs without carination and with numerous sensillar pitts （forelegs） as adaptations to life in nests analogical to the living termitophillous species; enlarged head, long palps for communication, a general venation modified in a direction towards termites （subcosta and radial vein [R] approximated, R branches approximated, simplified, cross-veins reduced）, and possibly also the development of the breaking forewing sutura for detaching wings after marriage flight）, suggest its eusocial mode of life. Thus, the first eusociality originated within cockroaches, prior to giving birth to termites; termites and Cryptocercus are not directly related. The group of eusocial cockroaches makes termite morphotaxon polyphyletic, but also in this case, the erection of a new order for mastotermites （including Cratomastotermitidae） and/or the inclusion of eusocial, morphological cockroaches within termites appears counterproductive, thus an example of such a general exception to the taxonomical procedure is provided.

关键词： fossil insect Mesozoic amber Blattida eusociality termite origin polyphyletic taxon new family

Possibilities for Healthcare Computing

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Journal of Computer Science & Technology 2011年第4期26卷 625-631页

作者： peter Szolovits Computer Science and Artificial Intelligence Laboratory Massachusetts Institute of Technology

Advances in computing technology promise to aid in achieving the goals of healthcare. We review how such changes can support each of the goals of healthcare as identified by the U.S. Institute of Medicine： safety, effectiveness, patient-centricity, timeliness, efficiency, and equitability. We also describe current foci of computing technology research aimed at realizing the ambitious goals for health information technology that have been set by the American Recovery and Reinvestment Act of 2009 and the Health Reform Act of 2010. Finally, we mention efforts to build health information technologies to support improved healthcare delivery in developing countries.

关键词： healthcare computing United States national plans meaningful use criteria substitutable applications medical natural language processing mobile health telehealth

Comorbidity in cirrhosis

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World Journal of Gastroenterology 2014年第23期20卷 7223-7230页

作者： peter Jepsen Department of Hepatology and Gastroenterology Aarhus University HospitalDK-8000 Aarhus CDenmark Department of Clinical Epidemiology Aarhus University HospitalDK-8000 Aarhus CDenmark

Cirrhosis patients’comorbidities are their other diseases than *** are neither causes nor consequences of cirrhosis,but they can increase mortality and are therefore clinically *** are also an important source of confounding in epidemiologic *** scoring systems have been developed as tools to measure the cirrhosis patient’s total burden of comorbidity,and they are useful in the clinic and for epidemiologic *** recently developed CirCom score is the only comorbidity scoring system developed specifically for cirrhosis patients,and it may be preferred over the older,generic,and more complex Charlson comorbidity *** of individual comorbid diseases can provide insight into the interactions between cirrhosis and other diseases and thus into the pathophysiology of *** article reviews the literature on comorbidity in cirrhosis.

关键词： Liver cirrhosis Comorbidity Prognosis Epidemiology

Medical therapy for spermatogenic failure

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Asian Journal of Andrology 2012年第1期14卷 57-60,176页

作者： Ranjith Ramasamy peter J Stahl peter N Schlegel Department of Urology Weill Cornell Medical College New York NY 10065 USA

Medical treatment of men with primary spermatogenic failure remains largely ineffective in contrast to those with secondary testicular failure. Treatment has been attempted with a multitude of agents ranging from hormones to nutritional supplements （antioxidants）. While some studies have demonstrated benefit to some treatments, no treatments have consistently demonstrated efficacy nor has it been possible to reliably identify patients likely to benefit. Idiopathic spermatogenic failure likely results from multiple discrete defects in sperm production that are as yet unidentified. A better understanding of these defects will yield more effective treatment options and appropriate triage of patients to specific therapeutic regimens. This review focuses on the rationale and current evidence for hormonal and antioxidant therapy in medical treatment of male infertility, spermatogenic failure in particular. Although empiric medical therapy for spermatogenic failure has been largely replaced by assisted reproductive techniques, both treatment modalities could play a role, oerhaos as combination therapy.

关键词： antioxidant hormones male infertility sperm spermatogenesis spermatogenic failure testicular failure

Accurate, automatic annotation of peptidases with hotpep-protease

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Green Chemical Engineering 2020年第2期1卷 124-130页

作者： peter Kamp Busk Department of Science and Environment Roskilde UniversityUniversitetsvej 1DK-4000RoskildeDenmark

Peptidases are essential for intracellular protein processing,signaling and homeostasis,physiological processes and for digestion of ***,peptidases are important biotechnological enzymes used in processes such as industrial food processing,leather manufacturing and the washing *** of peptidases is a crucial step in their characterization but peptidase annotation is not a trivial task due to their large sequence *** the present study short,conserved sequence profiles were generated for all peptidase families with more than four members in the comprehensive Merops peptidase *** sequence profiles were combined with the Homology to Peptide Pattern(Hotpep)method for automatic annotation of *** method is a standalone software that annotates protease sequences to Merops family and subgroup and is suitable for large-scale sequence *** to the Mammalian Degradome Database Hotpep-protease had an accuracy of 92%and a sensitivity of 96%for annotation of the human *** by commonly used methods(Blast and conserved domains)had an accuracy of 69%and a sensitivity of 78%.For fungal genomes,there were large differences between annotation with Hotpep-protease,Blast-and Hidden Markov Model-based annotation and the Merops annotation,which confirms the difficulty of large-scale peptidase *** annotation indicated that Hotpep-protease had a positive prediction rate of 0.90 compared to a positive prediction rate of 0.67 for Blast ***,Hotpep-protease is highly accurate method for fast and accurate annotation of peptidases.

关键词： Gene annotation Proteinase Proteolytic enzyme Peptidase Merops

Spin Polaron in a Diluted Parabolic Magnetic Quantum Well

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Communications in Theoretical Physics 2010年第4期53卷 782-786页

作者： A.John peter Department of Physics Zhejiang Institute of Modern Physics Zhejiang University

Theoretical investigations of spin polaron in a quantum well in the spin doping superlattice systems Cd1-xinMnxinTe/Cd1-xMnxout Te are presented in this paper. A variational procedure within the effective mass approximation is employed in the presence of magnetic field to calculate the donor ionization energy. Spin polaronic shifts are estimated using a mean field theory. The results show that the donor binding energy （i） Increases with the reduction in well sizes （ii） Decreases with the magnetic field is increased for a given well width （ill） Increases to a maximum value at 90 A and then decreases as the size of the well increases beyond 90 A and （iv） Spin polaronic shifts to the donor binding energy not only decrease in a magnetic field but also with the well width. The results are compared with the existing available literature.

关键词： spin polaron donor binding quantum dot semimagnetic system

A review of current understanding in tribochemical reactions involving lubricant additives

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Friction 2023年第4期11卷 489-512页

作者： Yan CHEN peter RENNER Hong LIANG Department of Materials Science and Engineering Texas A&M UniversityCollege Station 77843USA J.Mike Walker’66 Department of Mechanical Engineering Texas A&M UniversityCollege Station 77843USA

Lubricants have played important roles in friction and wear reduction and increasing efficiency of mechanical *** optimize tribological performance,chemical reactions between a lubricant and a substrate must be designed *** reactions are chemical reactions enabled or accelerated by mechanical *** activated lubricant additives play important roles in these *** this review,current understanding in mechanisms of chemical reactions under shear has been *** such as oil-soluble organics,ionic liquids(ILs),and nanoparticles(NPs)were analyzed in relation to the tribochemical reaction routes with elements in metallic *** results indicated that phosphorus,sulfur,fluorine,and nitrogen are key elements for tribochemical *** resulting tribofilms from zinc dithiophosphates(ZDDP)and molybdenum dithiocarbamate(MoDTC)have been widely reported,yet that from ILs and NPs need to investigate *** review serves as a reference for researchers to design and optimize new lubricants.

关键词： lubricant additives tribochemical reactions oil-soluble organics ionic liquids(ILs) nanoparticles(NPs)

Calibration of discrete element modeling: Scaling laws and dimensionless analysis

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Particuology 2022年第3期20卷 55-62页

作者： Yucang Wang peter Mora Yunpei Liang State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China College of Petroleum Engineering and Geosciences King Fahd University of Petroleum and MineralsSaudi Arabia

In this paper,dynamic similarity conditions are derived for discrete element simulations by non-dimensionalising the governing *** conditions must be satisfied so that the numerical model is a good representation of the physical *** a pure mechanical system,if three independent ratios of the corresponding quantities between the two models are set,then the ratios of other quantities must be chosen according to the similarity *** scalability of linear and non-linear contact laws is also *** tests of 3D uni-axial compression are carried out to verify the theoretical *** example is presented to show how to calibrate the model according to laboratory data and similarity ***,it is impossible to reduce computer time by scaling up or down certain parameters and continue to uphold the similarity *** results in this paper provide guidelines to assist discrete element modelers in setting up the model parameters in a physically meaningful way.

关键词： Discrete element method Dimensionless analysis Dynamic similarity Parameter calibration ESyS_Particle

The current perspective of the PA 1957 gas well pillar study and its implications for longwall gas well pillars

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International Journal of Mining Science and Technology 2021年第1期31卷 117-126页

作者： peter Zhang Daniel Su Chris Mark CDC NIOSH Pittsburgh Mining Research DivisionPittsburghPA 15236USA Mine Safety and Health Administration PittsburghPA 15217USA

Many states rely upon the Pennsylvania 1957 Gas Well Pillar Study to evaluate the coal barrier surrounding gas *** study included 77 gas well failure cases that occurred in the Pittsburgh and Freeport coal seams over a 25-year *** the time,coal was mined using the room-and-pillar mining method with full or partial pillar recovery,and square or rectangle pillars surrounding the gas wells were left to protect the *** study provided guidelines for pillar sizes under different overburden depths up to 213 m(700 ft).The 1957 study has also been used to determine gas well pillar sizes in longwall mines since longwall mining began in the 1970 *** original study was developed for room-and-pillar mining and could be applied to gas wells in longwall chain pillars under shallow ***,under deep cover,severe deformations in gas wells have occurred in longwall chain ***,with a better understanding of coal pillar mechanics,new insight into subsidence movements induced by retreat mining,and advances in numerical modeling,it has become both critically important and feasible to evaluate the adequacy of the 1957 study for longwall gas well *** this paper,the data from the 1957 study is analyzed from a new perspective by considering various factors,including overburden depth,failure location,failure time,pillar safety factor(SF),and floor *** pillar SF and floor pressure are calculated by considering abutment pressure induced by full pillar recovery.A statistical analysis is performed to find correlations between various factors and helps identify the most significant factors for the stability of gas wells influenced by retreat *** analyzing the data from the 1957 study,the guidelines for gas well pillars in the 1957 study are evaluated for their adequacy for roomand-pillar mining and their applicability to longwall *** modeling is used to model the stability of gas wells by quantifying the mining-induced s

关键词： Gas well pillar Pennsylvania 1957 gas well pillar study Room-and-pillar mining Longwall mining