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On a Classical Theorem on the Diameter and Minimum Degree of a Graph

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Acta Mathematica Sinica,English Series 2017年第11期33卷 1477-1503页

作者： veronica HERNANDEZ Domingo PESTANA Jose M. RODRIGUEZ Universidad CarlosⅢde Madrid Avenida de la Universidad3028911 LeganesSpain

In this work, we obtain good upper bounds for the diameter of any graph in terms of its minimum degree and its order, improving a classical theorem due to Erdos, Pach, Pollack and Tuza. We use these bounds in order to study hyperbolic graphs （in the Gromov sense）. To compute the hyperbolicity constant is an almost intractable problem, thus it is natural to try to bound it in terms of some parameters of the graph. Let H（n, δ0） be the set of graphs G with n vertices and minimum degree 50, and J（n, Δ） be the set of graphs G with n vertices and maximum degree A. We study the four following extremal problems on graphs： a（n,δ0） = min{δ（G）｜ G ∈H（n, δ0）}, b（n, δ0） =- max{δ（G）｜ e ∈H（n, δ0）}, α（n, Δ） = min{δ（G） [ G ∈ J（n, Δ）} and β（n,Δ） = max{δ（G） ] G∈Π（n,Δ）}. In particular, we obtain bounds for b（n, δ0） and we compute the precise value of a（n, δ0）, α（n, Δ） and w（n, Δ） for all values of n, r0 and A, respectively.

关键词： Extremal problems on graphs diameter minimum degree maximum degree Gromov hyperbolicity hyperbolicity constant finite graphs

Nanosized magnetite in low cost materials for remediation of water polluted with toxic metals, azo- and antraquinonic dyes

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 746-769页

作者： Maria Fernanda HORST veronica LASSALLE Maria Lujan FERREIRA Institute of Chemistry of the South (Inquisur Universidad Nacional del Sur~ONICET) Avda Alem 1253 Bahia Blanca Argentina Pilot Plant of Chemical Engineering (PLAPIQUI-UNS-CONICET) Universidad Nacional del Sur--CONICET Camino La Carrindanga km7 Bahia Blanca Argentina

Nanosized magnetite has emerged as an adsorbent of pollutants in water remediation. Nanoadsor- bents include magnetic iron oxide and its modifiers/ stabilizers, such as carbon, silica, clay, organic moieties （polymers, aminoaeids, and fatty acids） and other inorganic oxides. This review is focused on the recent developments on the synthesis and use of magnetic nanoparticles and nanocomposites in the treatment of contaminated water. The emphasis is on the influence of the iron oxide modifiers on some properties of interest such as size, BET area, and magnetization. The characteristics of these nanomaterials are related to their ability to eliminate heavy metal ions and dyes from wastewater. Comparative analysis of the actual literature was performed aiming to present the magnetic material, its preparation methodology and performance in the elimination of the selected pollutants. Vast information has been properly summarized according to the materials, their properties and preferential affinity for selected contaminants. The mechanisms governing nanomaterial＇s formation as well as the interactions with heavy metals and dyes have been carefully analyzed and associated to their efficiency.

关键词： nanomagnetite water remediation toxicmetals dyes supported magnetite

Landing in Ski Jumping: A Review About its Biomechanics and the Connected Injuries

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Journal of Science in Sport and Exercise 2021年第3期3卷 238-248页

作者： veronica Bessone Ansgar Schwirtz Department of Biomechanics in Sports Faculty of Sport and Health SciencesTechnical University of MunichMunichBavariaGermany

The present review deals with the current scientific knowledge related with ski jump landing.A specific focus is given on the landing biomechanics,the methods utilized for its analysis and the injuries connected to the landing *** the demonstrated importance for the safety and the performance of ski jumpers,the landing and its preparation are rarely *** this paper,after having firstly described the execution of landing and its preparation and the reason why is impor-tant to analyze it,an overview of the current status of the research related to the landing biomechanics is reported(kinetics,kinematics,electromyographic activation,aerodynamics,computer simulation).The third part describes the methods and technologies utilized in literature to analyze the landing and its preparation(video cameras,inertial sensors,force insoles,wind tunnel and computer simulation).After that,an overview of the injuries related to landing is *** final section proposes future research in the field of biomechanics of ski jump landing in different fields,such as computer simulations,kinematic analysis,equipment development and biomechanics of female athletes.

关键词： Feedback Sensors Prevention Kinetics Kinematics Winter sports

Tissue inhibitors of metalloproteases strike a nerve

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Neural Regeneration Research 2018年第11期13卷 1890-1892页

作者： veronica i.shubayev alex y.strongin department of anesthesiology university of californiasan diego va san diego healthcare system la jollacausa sanford burnham prebys medical discovery institute la jollacausa

Signals of touch,pressure,pain,temperature,position,and vibration are transmitted from the peripheral nervous system（PNS）to the dorsal horn of the segmental spinal cord via pseudounipolar dorsal root ganglia（DRG）*** information gathering relies on functional integrity of DRG neurons and can be interrupted by PNS injury due to trauma,disease or exposure to drugs, toxins or viral pathogens. Despite the high regenerative capacity of DRG neurons, sensory recovery after PNS injury is often incomplete and severe neuropathic pain may last for years. Although numerous mechanisms of PNS injury have been established, neuropathic pain is refractory to therapy, contributing to the physical and emotional suffering of patients and the enormous economic burden to society.

关键词： TIMPs PNS In Tissue inhibitors of metalloproteases strike a nerve

Antinociceptive and anti-inflammatory activities of crude extracts of Ipomoea involucrata leaves in mice and rats

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Asian Pacific Journal of Tropical Medicine 2011年第2期4卷 121-124页

作者： uche Fidelia Ijeoma Shorinwa Olusayo Aderonke Okorie Ogbonna Mgbahurike Amaka Augustina Chijioke-Nwauche Ifeyinwa Department of Pharmacognosy and Phytotherapy Faculty of Pharmaceutical SciencesUniversity of Port HarcourtNigeria Department of Clinical Pharmacy and Management Faculty of Pharmaceutical SciencesUniversity of Port HarcourtNigeria Department of Pharmaceutical Technology and Pharmaceutics Faculty of Pharmaceutical SciencesUniversity of Port HarcourtNigeria

Objective:To investigate antinociceptive and anti-inflammatory activities of crude extract from Ipomoea involucrata leaves(Convolvulaceae) in mice and ***:The antinociceptive activity was tested using acetic acid-induced abdominal writhing test in *** antiinflammatory activity was evaluated using egg albumin -induced oedema of rat ***: Phytochemical screening showed the presence of alkaloids,flavonoids,saponins,terpenoids and *** the doses of 25-100 mg/kg,Ipomoea involucrata exhibited dose-dependent and significant increase in pain threshold in acetic acid -induced writhing test of mice (P<0.05,student t-test) The administration of Ipomoea involucrata leaf extract(25-100 mg/ kg) showed dose-dependent decreases in paw volume of egg albumin induced oedema in rats and a significant higher anti-inflammatory activity compared to the standard control(Aspirin). Conclusions:These results support the claims on the traditional use of the of Ipomoea involucrata leaves in the treatment of toothache,rheumatic pains and other inflammatory *** on the isolation and structural elucidation of the active principle are still needed being carried out.

关键词： Ipomoea involucrata Antinociceptive Anti-inflammatory activity

Corneal compensation of presbyopia:PresbyLASIK:an updated review

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Eye and Vision 2017年第1期4卷 48-55页

作者： veronica Vargas-Fragoso Jorge L.Alió Vissum Corporation Edificio VissumCalle Cabañal 1AlicanteSpain Division of Ophthalmology Universidad Miguel HernándezCarretera Alicante-Valencia km 8.7AlicanteSpain.

The main purpose of this review is to compare and analyze the results of the main PresbyLASIK approaches;central and ***:A comprehensive research was conducted in PUBMED using keywords like“presbyopia correction”,“PresbyLASIK”,“Corneal multifocality”,“Laser blended vision”.We reviewed the PresbyLASIK technique,uncorrected distance visual acuity(UDVA),corrected distance visual acuity(CDVA),uncorrected near visual acuity(UNVA),and corrected near visual acuity(CNVA),and compared the differences between the techniques.

关键词： Central and peripheral PresbyLASIK Corneal multifocality Presbyopia

Pancreatic islet regeneration and some liver biochemical parameters of leaf extracts of Vitex doniana in normal and streptozotocin-induced diabetic albino rats

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Asian Pacific Journal of Tropical Biomedicine 2014年第2期4卷 124-130页

作者： Okpe Oche Ibrahim Sani Njoku Godwin Chiaka Ndidi uche Samuel Atabo Samuel Department of Biochemistry Ahmadu Bello UnirersityZariaNigeria

Objective:To test two water soluble extracts(aqueous and ethanolic) obtained from the leaves of Vitex doniana in normal and streptozotocin-induced diabetic rats for their effects on pancreatic endocrine tissues and serum marker enzymes for a period of 21 ***:A total of 55 rate divided into 11 groups of 5 rats each were assigned into diabetic and non-diabetic- groups and fallowed by a daily administration of ethanolic and aqueous extracts for21 *** 1 was the normal control while group 7 was treated with standard ***:The histopathological studies of the diabetic rats indicated increase in the volume density of islets,percent of β-cells and size of islet in the groups that received the plant extracts,which suggested regeneration of β-cells along with p-eells repairs,as compared with the non-treated diabetic control which showed complete degeneration of the islet *** was significant reduction(P0.01) in the serum activities of marker enzymes was observed for non-diabetic treated *** of total bilirubin,direct bilirubin and unconjugated bilirubin showed that diabetic control group was significantly higher(P0.01) in total bilirubin and direct bilirubin compared with the normal ***:This herbal therapy appears to bring about repair/regeneration of the endocrine pancreas and hepatic cells protection in the diabetic rat.

关键词： Vitex doniana Pancreatic islet Marker enzymes Diabetes Hepatoprotection

Acute hepatitis C in a chronically HIV-infected patient:Evolution of different viral genomic regions

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World Journal of Gastroenterology 2003年第7期9卷 1496-1500页

作者： Diego Flichman veronica Kott Silvia Sookoian Rodolfo Campos Catedra de Virologia Facultad de Farmacia y BioquimicaUniversidad de Buenos AiresArgentina Unidad de Higado Hospital"Dr.Cosme Argerich"Argentina

AIM: To analyze the molecular evolution of different viral genomic regions of HCV in an acute HCV infected patient chronically infected with HIV through a 42-month ***: Serum samples of a chronically HIV infected patient that seroconverted to anti HCV antibodies were sequenced, from the event of superinfection through a period of 17 months and in a late sample (42nd month). Hypervariable genomic regions of HIV (V3 loop of the gp120) and HCV (HVR-1 on the E2 glycoprotein gene) were studied. In order to analyze genomic regions involved in different biological functions and with the cellular immune response, HCV core and NS5A were also chosen to be sequenced. Amplification of the different regions was done by RT-PCR and directly sequenced. Confirmation of sequences was done on reamplified material. Nucleotide sequences of the different time points were aligned with CLUSTAL W 1.5, and the corresponding amino acid ones were ***: Hypervariable genomic regions of both viruses (HVR1 and gp120 V3 loop) presented several nonsynonymous changes but, while in the gp120 V3 loop mutations were detected in the sample obtained right after HCV superinfection and maintained throughout, they occurred following a sequential and cumulative pattern in the HVR1. In the NS5A region of HCV, two amino acid changes were detected during the follow-up period, whereas the core region presented several amino acid replacements, once the HCV chronic infection had been ***: During the HIV-HCV superinfection, each genomic region analyzed shows a different evolutionary *** of the nucleotide substitutions observed are nonsynonymous and clustered in previously described epitopes,thus suggesting an immune-driven evolutionary process.

关键词： Acute Disease Adolescent Amino Acid Sequence Female Genome, Viral HIV HIV Envelope Protein gp120 HIV Infections Hepacivirus Hepatitis C Humans Molecular Sequence Data Research Support, Non-U.S. Gov't Superinfection Viral Nonstructural Proteins Viral Proteins

Diversity of Arbuscular Mycorrhizal Fungi Associated with Six Rice Cultivars in Italian Agricultural Ecosystem Managed with Alternate Wetting and Drying

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Rice science 2023年第4期30卷 348-358,I0028-I0030页

作者： veronica VOLPE Franco MAGURNO Paola BONFANTE Stefano GHIGNONE Erica LUMINI Department of Life Sciences and Systems Biology University of TurinV.le P.A.Mattioli 25I-10125 TurinItaly Institute of Biology Biotechnology and Environmental ProtectionFaculty of Natural SciencesUniversity of Silesia in KatowiceJagiellońska 28Katowice 40-032Poland Institute for Sustainable Plant Protection-Turin Unit National Research Council of ItalyV.le P.A.Mattioli 25I-10125 TurinItaly

Alternate wetting and drying(AWD)system,in which water has been reduced by approximately 35%with an increased occurrence of beneficial arbuscular mycorrhizal(AM)symbiosis and no negative impact on rice yield,was proposed to utilize water and nutrients more *** this study,we selected six rice cultivars(Centauro,Loto,Selenio,Vialone nano,JSendra and Puntal)grown under AWD conditions,and investigated their responsiveness to AM colonization and how they select diverse AM *** order to investigate root-associated AM fungus communities,molecular cloning-Sanger sequencing on small subunit rDNA data were obtained from five out of the six rice cultivars and compared with Next Generation Sequencing(NGS)data,which were previously obtained in Vialone *** results showed that all the cultivars were responsive to AM colonization with the development of AM symbiotic structures,even if with differences in the colonization and arbuscule abundance in the root *** identified 16 virtual taxa(VT)in the soil compartment and 7 VT in the root *** emphasized that the NGS analysis gives additional value to the results thanks to a more in-depth reading of the less represented AM fungus taxa.

关键词： alternate wetting and drying system arbuscular mycorrhizal fungi rice molecular diversity virtual taxa