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Algorithms for Computing Some Invariants for Discrete Knots

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Applied Mathematics 2013年第11期4卷 1526-1530页

作者： gabriela Hinojosa David Torres Rogelio Valdez Facultad de Ciencias Universidad Autónoma del Estado de Morelos Cuernavaca México

Given a cubic knot K, there exists a projection? of the Euclidean space R3?onto a suitable plane ?such that p(K) is a knot diagram and it can be described in a discrete way as a cycle permutation. Using this fact, we develop an algorithm for computing some invariants for K: its fundamental group, the genus of its Seifert surface and its Jones polynomial.

关键词： Cubic Knots Discrete Knots Algorithms

Medical management of symptomatic severe aortic stenosis in patients non-eligible for transcatheter aortic valve implantation

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Journal of Geriatric Cardiology 2020年第11期17卷 704-709页

作者： gabriela Silvia Gheorghe Andreea Simona Hodorogea Andrei Cristian Dan Gheorghe Ioan Tiberiu Nanea Ana Ciobanu University of Medicine and Pharmacy Carol Davila BucharestProf.Dr.Th.Burghele HospitalBucharestRomania

1 Transcatheter aortic valve implantation in symptomatic severe aortic stenosis: where do we stand? Aortic stenosis occurs in 2%-9% of patients over the age of 65, the most common cause being degenerative.^([1,2]) The preferred treatment in symptomatic severe aortic stenosis(SAS) is surgical aortic valve replacement(SAVR), but in the elderly, the surgical risk can be greater than the benefit.([3]).

关键词： Angiotensin-converting enzyme inhibitors Beta-blockers Calcium channel blockers Diuretics Symptomatic severe aortic stenosis Transcatheter aortic valve implantation

Application of polyurethane geocomposites to help maintain track geometry for high-speed ballasted railway tracks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第11期13卷 836-849页

作者： Peter Keith WOODWARD Abdellah EL KACIMI Omar LAGHROUCHE gabriela MEDERO Meysam BANIMAHD Institute for Infrastructure and Environment School of the Built EnvironmentHeriot-Watt UniversityEdinburghEH14 4ASUK

There are many issues surrounding the performance of critical assets on high-speed ballasted railway *** assets like switch & crossings and bridge transitions high track forces can be produced resulting in higher ballast settlements and hence track *** latter result in higher track forces and hence more settlement,leading to the need for increased track maintenance to ensure comfort and *** technologies for solving issues like ballast movement under high-speed loading regimes are ***,a technique that has been well used across the UK and now increasingly overseas to stabilise and reinforce ballasted railway tracks is the application of in-situ polyurethane polymers,termed *** paper discusses how this technique can be used to solve these types of long-standing issues and presents actual polymer application profiles at two typical critical sites,namely a junction and a transition onto concrete slab-track.

关键词： Railways Polyurethanes Geocomposites Modelling High-speed

Oxidative stress, antioxidants and intestinal calcium absorption

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World Journal of Gastroenterology 2017年第16期23卷 2841-2853页

作者： gabriela Diaz de Barboza Solange Guizzardi Luciana Moine Nori Tolosa de Talamoni Laboratorio“Dr.Fernando Canas” Cátedra de Bioquímica y Biología MolecularFacultad de Ciencias MédicasINICSA(CONICET-Universidad Nacional de Córdoba)Pabellón ArgentinaCiudad UniversitariaCórdoba 5000Argentina

The disequilibrium between the production of reactive oxygen(ROS) and nitrogen(RNS) species and their elimination by protective mechanisms leads to oxidative stress. Mitochondria are the main source of ROS as by-products of electron transport chain. Most of the time the intestine responds adequately against the oxidative stress, but with aging or under conditions that exacerbate the ROS and/or RNS production, the defenses are not enough and contribute to developing intestinal pathologies. The endogenous antioxidant defense system in gut includes glutathione(GSH) and GSH-dependent enzymes as major components. When the ROS and/or RNS production is exacerbated, oxidative stress occurs and the intestinal Ca2+ absorption is inhibited. GSH depleting drugs such as DLbuthionine-S,R-sulfoximine, menadione and sodium deoxycholate inhibit the Ca2+ transport from lumen to blood by alteration in the protein expression and/or activity of molecules involved in the Ca2+ transcellular and paracellular pathways through mechanisms of oxidative stress, apoptosis and/or autophagy. Quercetin, melatonin, lithocholic and ursodeoxycholic acids block the effect of those drugs in experimental animals by their antioxidant, anti-apoptotic and/or anti-autophagic properties. Therefore, they may become drugs of choice for treatment of deteriorated intestinal Ca2+ absorption under oxidant conditions such as aging, diabetes, gut inflammation and other intestinal disorders.

关键词： Transcellular and paracellular Ca2+pathways DL-buthionine-S R-sulfoximine Menadione Sodium deoxycholate Lithocholic acid Ursodeoxycholic acid Melatonin

Are extrafloral nectaries efficient against herbivores? Herbivory and plant defenses in contrasting tropical species

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Journal of Plant Ecology 2020年第4期13卷 423-430页

作者： Cássio Cardoso Pereira Maria gabriela Boaventura Gislene Carvalho de Castro Tatiana Cornelissen Departamento de Genética Ecologia e EvoluçãoUniversidade Federal de Minas Gerais31270-910 Belo HorizonteMGBrazil Departamento de Ciências Naturais Universidade Federal de São João del-Rei36301-160 São João del-ReiMGBrazil

Aims Plants have limited resources for defenses and species that invest in biotic defenses might exhibit leaves that invest less in other types of *** have investigated whether plants that have few mechanical defenses,but have extrafloral nectaries(EFNs)patrolled by ants,are less prone to herbivory,compared with plants without EFNs that have tougher *** Data from the literature were extracted to examine the reported levels of herbivory in plants with or without *** a savanna vegetation in southern Brazil,field data were collected in leaves from six tropical species and herbivory and specific leaf area(SLA)levels were *** further evaluated differences in herbivory and SLA among species and between plants with or without *** order to test the relationship between herbivory and leaf toughness we regressed average herbivory and average SLA per *** Findings Plants exhibited variable levels of leaf damage,but plants without ant defenses experienced the highest levels of leaf area loss to *** of mechanical defenses were also variable among the plant *** without EFNs were tougher,exhibiting lower values of *** plants without EFNs had more sclerophyllous leaves,this mechanical defense was not sufficient to impair and/or reduce herbivore feeding,suggesting that the biotic defenses performed by patrolling ants might be more effective than investment in mechanical defenses associated with leaf palatability.

关键词： ants biotic defenses herbivory leaf palatability specific leaf area

Non-alcoholic Fatty Liver Disease in South Asians:A Review of the Literature

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Journal of Clinical and Translational Hepatology 2017年第1期5卷 76-81页

作者： Sital Singh gabriela N.Kuftinec Souvik Sarkar Division of Gastroenterology and Hepatology and Department of Internal Medicine University of CaliforniaDavisUSA Department of Internal Medicine University of CaliforniaDavisUSA

Non-alcoholic fatty liver disease(NAFLD)and non-alcoholic steatohepatitis(NASH)are national and global *** disease is characterized by a spectrum of liver steatosis(fat deposition),inflammation(in NASH)and *** and specifically NASH can lead to cirrhosis,which carry risks of progression to portal hypertension and hepatocellular carcinoma(HCC).NASH is also associated with higher mortality from cardiovascular *** of the data for NAFLD has been obtained from the perspective of developed nations,although the disease is increasing and threatening to reach epidemic proportions across the *** data is notable for high prevalence of NAFLD in South Asian populations,presumably resulting from a combination of underlying genetic polymorphisms and changes in socio-economic *** is also notable that an‘Asian Paradox'has been defined for NAFLD based upon the observation of lower than predefined body mass index(BMI),otherwise termed as"lean NAFLD",among this ***,data remains limited in regards to the characteristics of NAFLD/NASH in this *** this article,we present a review of the literature and discuss the prevalence,associated risk factors and burden of HCC in South Asians with NAFLD.

关键词： Non-alcoholic fatty liver disease(NAFLD) Non-alcoholic steatohepatitis(NASH) South Asia

Lack of functional link in the tadpole morphology induced by predators

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Current Zoology 2016年第3期62卷 227-235页

作者： Maria gabriela PEROTTI Mariana PUETA Fabian Gaston JARA Carmen Adria UBED Debora Lina MORENO AZOCAR Laboratorio de Fotobiologfa INIBIOMA CONICET-Universidad Nacional del Comahue O.uintral 1250 Bariloche Rio Negro Argentina Departamento de Biologfa General. Universidad Nacional del Comahue Quintral 1250 Bariloche Rio Negro Argentina Departamento de Zoologia INIBIOMA CONICET-Universidad Nacional del Comahue Quintral 1250 8400 Bariloche Rio Negro Argentina

Most studies of predator-induced plasticity have focused on documenting how prey species re- spond to predators by modifying phenotypic traits and how traits correlate with fitness. We have previously shown that Pleurodema thaul tadpoles exposed to the dragonfly Rhionaeschna varie- gata responded strongly by showing morphological changes, less activity, and better survival than non-exposed tadpoles. Here, we tested whether there is a functional link between morphological plasticity and increased survival in the presence of predators. Tadpoles that experienced predation risk were smaller, less developed, and much less active than tadpoles without this experience. Burst speed did not correlate significantly with morphological changes and predator-induced deeper tails did not act as a lure to divert predator strikes away from the head. Although we have previously found that tadpoles with predator-induced morphology survive better under a direct predator threat, our results on the functional link between morphology and fitness are not conclu- sive. Our results suggest that in P. thaultadpoles （1） burst speed is not important to evade preda- tors, （2） those exposed to predators reduce their activity, and （3） morphological changes do not divert predator attacks away from areas that compromise tadpole survivalEE. Our results show that morphological changes in P. thaul tadpoles do not explain burst speed or lure attraction, al- though there was a clear reduction of activity, which itself reduces predation. We propose that changes in tadpole activity could be further analyzed from another perspective, with morphological change as an indirect product of behavior mediated by physiological mechanisms.

关键词： induced morphology lure effect predator exposure swimming performance tadpoles.

Occupational risk of exposure to methicillin-resistant Staphylococcus aureus(MRSA)and the quality of infection hygiene in nursing homes

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Frontiers of Environmental Science & Engineering 2021年第3期15卷 111-121页

作者： Pil Uthaug Rasmussen Katrine Uhrbrand Mette Damkjaer Bartels Helle Neustrup Dorina gabriela Karottki Ute Biiltmann Anne Mette Madsen National Research Centre for the Working Environment Lerso Parkalle 1052100 Copenhagen 0Denmark Department of Clinical Microbiology Hvidovre HospitalKettegdrd Alle 302650 HvidovreDenmark The Danish Working Environment Authority Landskronagade 332100 CopenhagenDenmark University Medical Center Groningen Department of Health SciencesCommunity&Occupational MedicineUniversity of Groningen9700 GroningenThe Netherlands

Methicillin-resistant Staphylococcus aureus(MRSA)is an increasing health concern across the globe and is often prevalent at long-term care facilities,such as nursing ***,we know little of whether nursing home staff is exposed to MRSA via air and *** investigated whether staff members at nursing homes are colonised with and exposed to culturable MRSA,and assessed staff members'self-reported knowledge of MRSA and compliance with infection hygiene *** nursing homes with MRSA positive residents were visited in Copenhagen,*** bioaerosol exposure samples and environmental samples from surfaces,sedimented dust and bioaerosols were examined for MRSA and methicillin-suscqjtible ***(MSSA)to determine occupational *** were taken from staffs*nose,throat,and hands to determine whether they were colonised with *** online questionnaire about MRSA and infection control was *** staff members were colonised with MRSA,but MRSA was detected in the rooms of the colonised residents in two out of the five nursing *** was observed in air(n=4 out of 42,ranging from 2.9-1.9 CFU/m^(3)),sedimented dust(n=1 out of 58,1.1 ×10^(3) CFU/m^(2)/d),and on surfaces(n=9 out of 113,0.04-70.8 CFU/m^(2)).The questionnaire revealed that half of the staff members worry about spreading MRSA to *** aspects for improvement were improved availability and use of protective equipment,not transferring cleaning supplies(e.g.,vacuum cleaners)between residents'rooms and to reduce worry of MRSA,e.g.,through education.

关键词： Antibiotic resistance Airborne MRSA Bioaerosols Healthcare-associated infections Healthcare worker Occupational health

A randomized,fellow eye,comparison of keratometry,aberrometry,tear film,axial length and the anterior chamber depth after eye rubbing in non-keratoconic eyes

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Eye and Vision 2017年第1期4卷 106-113页

作者： Jordan V.Chervenkoff Elizabeth Hawkes gabriela Ortiz Deborah Horney Mayank A.Nanavaty Sussex Eye Hospital Brighton&Sussex University Hospitals NHS TrustEastern RoadBrighton BN25BFUK

Background:To investigate the effect of eye rubbing on keratometry(K),aberrometry,tear film break-up-time(TFBUT)and anterior chamber depth(ACD).Methods:Volunteers without any corneal pathology or dry eyes were randomised to rubbing in one eye and the fellow-eye was *** rubbing was performed for 2 *** outcomes studied were anterior and posterior K *** outcomes were changes in TFBUT,axial length(AL)&ACD,K changes in various zones,asphericity and *** and post rubbing K,aberrometry,ACD and TFBUT were assessed in a predetermined *** relationship of the above parameters to axial length(AL)was also *** was analysed using vector ***:Pre versus post rubbing,anterior flatter K further flattened(42.51±1.52 D vs.42.36±1.53 D,p=0.003)and the changes to J0 vector in central cornea(−0.16±0.26 D vs.-0.27±0.33 D,p=0.038)suggested change to against-the-rule(ATR)*** was significant change in Z^(+2)_(2) polynomial following *** found a positive correlation between axial length and change in posterior K(r=0.335,p=0.020).The TFBUT reduced following eye rubbing(15.3 s vs.13.9 s,p=0.0001).There was a positive correlation between AL and increase in ACD post rubbing(r=0.300,p=0.038).There was a positive correlation between ACD and change in mean posterior K(r=0.305,p=0.035).Conclusions:In healthy eyes,following eye rubbing,there is a significant change in TFBUT and central anterior K changes towards ATR *** eyes had more changes in posterior K and ***,eyes with deeper ACD showed more steepness of posterior K.

关键词： Eye rubbing Ectasia Tear film break up time Astigmatism Aberrations