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Underground Space 2018年第1期3卷 1-20页

作者： g.Meschke Institute for Structural Mechanics Ruhr University BochumBochumGermany

This paper reports on planning and construction related results from research performed at the Collaborative Research Center“Interaction Modeling in Mechanized Tunneling”at Ruhr-University Bochum,*** covers a broad spectrum of topics relevant for mechanized tunneling in soft soil *** includes inverse numerical methods for advance exploration and models for the characterization of the in situ ground conditions,the interaction of the face support and the tail gap grouting with the porous soil,multi-scale models for the design ofﬁber reinforced segmental linings with enhanced robustness,computational methods for the numer-ical simulation of the tunnel advancement,the soil excavation and the material transport in the pressure chamber,logistics processes and risk analysis in urban *** towards the continuous support of the construction process,a concept for real-time steering support of tunnel boring machines in conjunction with model update procedures and methods of uncertainty quantiﬁcation is addressed.

关键词： Mechanized tunneling Computational simulation Tunnel reconnaissance Tunnel linings Face support Tail void grouting Real-time ana-lysis Abrasion Process simulation

SOME FURTHER NOTES ON THE MATRIX EQUATIONS A^TXB+B^TX^TA=C AND A^TXB+B^TXA=C

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Acta Mathematica Scientia 2015年第1期35卷 275-280页

作者： g.SOARES Center of Mathematics University of Trás-os-Montes of Alto Douro

Dehghan and Hajarian, [4], investigated the matrix equations A^TXB＋B^TX^TA = C and A^TXB ＋ B^TXA = C providing inequalities for the determinant of the solutions of these equations. In the same paper, the authors presented a lower bound for the product of the eigenvalues of the solutions to these matrix equations. Inspired by their work, we give some generalizations of Dehghan and Hajarian results. Using the theory of the numerical ranges, we present an inequality involving the trace of C when A, B, X are normal matrices satisfying A^T B = BA^T.

关键词： matrix equation eigenvalue trace permutation matrix

Challenges of a feasible route towards sustainability in environmental protection

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Frontiers of Environmental Science & Engineering 2010年第2期4卷 123-134页

作者： g.LETTINgA LeAF-foundation Sub-department of Environmental TechnologyWageningen UniversityP.O.box 81206700 EVWageningenNetherlands

Anaerobic processes for treatment of low and high strength wastewaters and solid wastes constitute the core method in the natural biological mineralization(NBM)treatment *** adequately combined with the complementary NBM-systems and modern clean water saving practices in wastewater collection and transport,they represent a feasible route to sustainable environmental protection(EPsus),in essence even towards a more sustainable *** the development and implementation of modern high rate Anaerobic Wastewater Treatment(AnWT-)systems and complementary innovative NBM-processes,the considerable progress made since the seventies in fundamental insights in microbiology,biochemistry and process technology,still numerous challenging improvements in the NBM-field can be *** contribution is mainly based on the insights attained from wide ranging literature evaluations and the results of experimental research conducted by numerous PhD students who participated in our group over the last four *** attempt is made here to identify major facets on which an improved insight can,and consequently should,be obtained in order to accomplish more optimal operation and design of various types of Anaerobic Degradation(AnDeg-)processes.

关键词： sustainability environmental protection anaerobic treatment micro-aerobic treatment natural biological mineralization concept traces elements macro-nutrients

The epididymis, cytoplasmic droplets and male fertility

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Asian Journal of Andrology 2011年第1期13卷 130-138页

作者： Trevor g Cooper Centre of Reproductive Medicine and Andrology University of MOnster MOnster D-48149 Germany

The potential of spermatozoa to become motile during post-testicular maturation, and the relationship between the cytoplasmic droplet and fertilizing capacity are reviewed. Post-testicular maturation of spermatozoa involves the autonomous induction of motility, which can occur in vivo in testes with occluded excurrent ducts and in vitro in testicular explants, and artefactual changes in morphology that appear to occur in the testis in vitro. Both modifications may reflect time-dependent oxidation of disulphide bonds of head and tail proteins. Regulatory volume decrease （RVD）, which counters sperm swelling at ejaculation, is discussed in relation to loss of cytoplasmic droplets and consequences for fertility. It is postulated that：（i） fertile males possess spermatozoa with sufficient osmolytes to drive RVD at ejaculation, permitting the droplet to round up and pinch off without membrane rupture; and （ii） infertile males possess spermatozoa with insufficient osmolytes so that RVD is inadequate, the droplet swells and the resulting flagellar angulation prevents droplet loss. Droplet retention at ejaculation is a harbinger of infertility caused by failure of the spermatozoon to negotiate the uterotubal junction or mucous and reach the egg. In this hypothesis, the epididymis regulates fertility indirectly by the extent of osmolyte provision to spermatozoa, which influences RVD and therefore droplet loss. Man is an exception, because ejaculated human spermatozoa retain their droplets. This may reflect their short midpiece, approximating head length, permitting a swollen droplet to extend along the entire midpiece; this not only obviates droplet migration and flagellar angulation but also hampers droplet loss.

关键词： epididymis fertility infertility sperm maturation

An Effective Classifier Model for Imbalanced Network Attack Data

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Computers, Materials & Continua 2022年第12期73卷 4519-4539页

作者： gürcan Ctin Department of Information System Engineering Mugla SıtkıKo鏼an UniversityMugla48000Turkey

Recently,machine learning algorithms have been used in the detection and classification of network *** performance of the algorithms has been evaluated by using benchmark network intrusion datasets such as DARPA98,KDD’99,NSL-KDD,UNSW-NB15,and Caida ***,these datasets have two major challenges:imbalanced data and highdimensional *** high accuracy for all attack types in the dataset allows for high accuracy in imbalanced *** the other hand,having a large number of features increases the runtime load on the algorithms.A novel model is proposed in this paper to overcome these two *** number of features in the model,which has been tested at CICIDS2017,is initially optimized by using genetic *** optimum feature set has been used to classify network attacks with six well-known classifiers according to high f1-score and g-mean value in ***,amulti-layer perceptron based ensemble learning approach has been applied to improve the models’overall *** experimental results showthat the suggested model is acceptable for feature selection as well as classifying network attacks in an imbalanced dataset,with a high f1-score(0.91)and g-mean(0.99)***,it has outperformed base classifier models and voting procedures.

关键词： Ensemble methods feature selection genetic algorithm multilayer perceptron network attacks imbalanced data

Controversies in and challenges to our understanding of hepatitis C

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World Journal of gastroenterology 2007年第31期13卷 4168-4176页

作者： Robert g Batey Area Director Drug and Alcohol Clinical Services Hunter New England Area Health Services. Newcastle New South Wales Australia

Discovered in 1989, the hepatitis C virus (HCV) continues to cause signifi cant morbidity and mortality world-wide despite a huge research commitment to defining and understanding the virus and the disease it causes. This paper discusses a number of areas where progress in the management of the HCV have not kept pace with the scientifi c understanding of the HCV. It is suggested that in the fi elds of HCV prevention and providing access to treatment, practice falls short of what could be achieved. The role of alcohol in the pathogenesis of HCV liver injury is discussed. Discrimination against those with HCV infection and particularly those in prison settings fails to match good clinical practice. The complicated processes of sharing information between specialty groups is also discussed in an attempt to optimise knowledge dissemination in this field.

关键词： Hepatitis C Alcohol Injecting drug use Prisons genetic variation Cirrhosis Liver cell cancer

Performance of Lung Cancer Prediction Methods Using Different Classification Algorithms

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Computers, Materials & Continua 2021年第5期67卷 2015-2028页

作者： Yasemin gültepe Department of Computer Engineering Engineering and Architecture FacultyKastamonu UniversityKastamonu37200Turkey

In 2018,1.76 million people worldwide died of lung *** of these deaths are due to late diagnosis,and early-stage diagnosis significantly increases the likelihood of a successful treatment for lung *** learning is a branch of artificial intelligence that allows computers to quickly identify patterns within complex and large datasets by learning from existing ***-learning techniques have been improving rapidly and are increasingly used by medical professionals for the successful classification and diagnosis of early-stage *** are widely used in cancer *** particular,machine learning has been used in the diagnosis of lung cancer due to the benefits it offers doctors and *** this context,we performed a study on machine-learning techniques to increase the classification accuracy of lung cancer with 32×56 sized numerical data from the Machine Learning Repository web site of the University of California,*** this study,the precision of the classification model was increased by the effective employment of pre-processing methods instead of direct use of classification *** datasets were derived with pre-processing methods and six machine-learning classification methods were used to achieve this *** study results suggest that the accuracy of the k-nearest neighbors algorithm is superior to random forest,naïve Bayes,logistic regression,decision tree,and support vector *** performance of pre-processing methods was assessed on the lung cancer *** most successful preprocessing methods were Z-score(83%accuracy)for normalization methods,principal component analysis(87%accuracy)for dimensionality reduction methods,and information gain(71%accuracy)for feature selection methods.

关键词： Lung cancer machine learning dimensionality reduction normalization feature selection

Phenotypic plasticity in the monoclonal marbled crayfish is associated with very low genetic diversity but pronounced epigenetic diversity

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Current Zoology 2023年第4期69卷 426-441页

作者： günter Vogt Faculty of Biosciences University of HeidelbergIm Neuenheimer Feld 23469120 HeidelbergGermany

Clonal organisms are particularly useful to investigate the contribution of epigenetics to phenotypic plasticity,because confounding effects of genetic variation are *** the last decade,the apomictic parthenogenetic marbled crayfish,Procambarus virginalis,has been developed as a model to investigate the relationships between phenotypic plasticity and genetic and epigenetic diversity in *** crayfish originated about 30 years ago by autotriploidy from a single slough crayfish Procambarus *** the result of human releases and active spreading,marbled crayfish has established numerous populations in very diverse habitats in 22 countries from the tropics to cold temperate *** in the laboratory and field revealed considerable plasticity in coloration,spination,morphometric parameters,growth,food preference,population structure,trophic position,and niche *** and PacBio whole-genome sequencing of marbled crayfish from representatives of 19 populations in Europe and Madagascar demonstrated extremely low genetic diversity within and among populations,indicating that the observed phenotypic diversity and ability to live in strikingly different environments are not due to adaptation by selection on genetic *** contrast,considerable differences were found between populations in the DNA methylation patterns of hundreds of genes,suggesting that the environmentally induced phenotypic plasticity is mediated by epigenetic mechanisms and corresponding changes in gene *** DNA methylation fingerprints persisted in local populations over successive years indicating the existence of epigenetic ecotypes,but there is presently no information as to whether these epigenetic signatures are transgenerationally inherited or established anew in each generation and whether the recorded phenotypic plasticity is adaptive or nonadaptive.

关键词： DNA methylation environmental adaptation epigenetics epigenetic ecotypes marbled crayfish phenotypic plasticity whole-genome sequencing

global case studies of soft-sediment deformation structures(SSDS): Definitions,classifications, advances, origins, and problems

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Journal of Palaeogeography 2017年第4期6卷 251-320页

作者： g.Shanmugam Department of Earth and Environmental Sciences The University of Texas at Arlington

Soft-sediment deformation structures（SSDS）have been the focus of attention for over 150 *** unconstrained definitions allow one to classify a wide range of features under the umbrella phrase＂SSDS＂.As a consequence,a plethora of at least 120 different types of SSDS（e.g.,convolute bedding,slump folds,load casts,dish-and-pillar structures,pockmarks,raindrop imprints,explosive sandegravel craters,clastic injections,crushed and deformed stromatolites,etc.）have been recognized in strata ranging in age from Paleoproterozoic to the present *** two factors that control the origin of SSDS are prelithification deformation and liquidization.A sedimentological compendium of 140 case studies of SSDS worldwide,which include 30 case studies of scientific drilling at sea（DSDP/ODP/IODP）,published during a period between 1863and 2017,has yielded at least 31 different *** have remained the single most dominant cause of SSDS because of the prevailing＂seismite＂*** advances on SSDS research are：（1）an experimental study that revealed a quantitative similarity between raindrop-impact cratering and asteroid-impact cratering;（2）IODP Expedition 308 in the gulf of Mexico that documented extensive lateral extent（〉12 km）of mass-transport deposits（MTD）with SSDS that are unrelated to earthquakes;（3）contributions on documentation of pockmarks,on recognition of new structures,and on large-scale sediment deformation on *** that hinder our understanding of SSDS still *** are：（1）vague definitions of the phrase＂soft-sediment deformation＂;（2）complex factors that govern the origin of SSDS;（3）omission of vital empirical data in documenting vertical changes in facies using measured sedimentological logs;（4）difficulties in distinguishing depositional processes from tectonic events;（5）a model-driven interpretation of SSDS（i.e.,earthquake being the singular cause）;（6）routine application of the genetic term＂seismites＂to the＂SSDS＂,thus undermining the

关键词： Soft-sediment deformation structures(SSDS) Prelithification deformation Liquidization Pockmarks Impact cratering Scientific drilling

Molecular basis of ataxia telangiectasia and related diseases

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Acta Pharmacologica Sinica 2005年第8期26卷 897-907页

作者： Lindsay g Ball Department of Microbiotogy and Lmmunology University of Saskatchewan S7n 5E5 SK Canada Saskatoon

Ataxia telangiectasia (AT) is a rare human disease characterized by extreme cellular sensitivity to radiation and a predisposition to cancer, with a hallmark of onset in early childhood. Several human diseases also share similar symptoms with AT albeit with different degrees of severity and different associated disorders. While all AT patients contain mutations in the AT-mutated gene (ATM), most other AT-like disorders are defective in genes encoding an MRN protein complex consisting of Mre11, Rad50 and Nbs1. Both ATM and MRN function as cellular sensors to DNA double-strand breaks, which lead to the recruitment and phosphorylation of an array of substrate proteins involved in DNA repair, apoptosis and cell-cycle cbeckpoints, as well as gene regulation, translation initiation and telomere maintenance. ATM is a member of the family of phosphatidylinositol 3-kinase-like protein kinases (PIKK), and the discovery of many ATM substrates provides the underlying mechanisms of heterologous symptoms among AT patients. This review article focuses on recent findings related to the initial recognition of double-strand breaks by ATM and MRN, as well as a DNA-dependent protein kinase complex consisting of the heterodimer Ku70/Ku80 and its catalytic subunit DNA-PKcs, another member of PIKK. This possible interaction suggests that a much greater complex is involved in sensing, transducing and co-ordinating cellular events in response to genome instability.

关键词： ataxia telangiectasia DNA damage DNA repair cdc genes phosphotransferases