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Transmission potential of the novel coronavirus (COVID-19) onboard the diamond Princess Cruises Ship, 2020

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Infectious Disease Modelling 2020年第1期5卷 264-270页

作者： Kenji Mizumoto gerardo Chowell Graduate School of Advanced Integrated Studies in Human Survivability Kyoto University Yoshida-Nakaadachi-choSakyo-kuKyotoJapan Hakubi Center for Advanced Research Kyoto UniversityYoshidahonmachiSakyo-kuKyotoJapan Department of Population Health Sciences School of Public HealthGeorgia State UniversityAtlantaGeorgiaUSA Division of International Epidemiology and Population Studies Fogarty International CenterNational Institutes of HealthBethesdaUSA

An outbreak of COVID-19 developed aboard the Princess Cruises Ship during January eFebruary *** mathematical modeling and time-series incidence data describing the trajectory of the outbreak among passengers and crew members,we characterize how the transmission potential varied over the course of the *** estimate of the mean reproduction number in the confined setting reached values as high as^11,which is higher than mean estimates reported from community-level transmission dynamics in China and Singapore(approximate range:1.1e7).Our findings suggest that Rt decreased substantially compared to values during the early phase after the Japanese government implemented an enhanced quarantine *** recent estimates of Rt reached values largely below the epidemic threshold,indicating that a secondary outbreak of the novel coronavirus was unlikely to occur aboard the Diamond Princess Ship.

关键词： Corona Epidemic Confined settings Cruise Next generation matrix

Influence of parameters on the microstructure of a duplex stainless steel joint welded by a GMAW welding process

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Progress in Natural Science:Materials International 2022年第4期32卷 415-423页

作者： Sandra Chacón-Fernández Antonio Portolés García gerardo Romaní Labanda Universidad Politécnica de Madrid Escuela Técnica Superior de Ingenieros Industriales UPM

Duplex stainless steels（DSSs） are widely used in industry for their desirable properties. Any fusion welding technique modifies the microstructure and, consequently, the properties of the material. This paper presents a parametric study of the variables that determine the energy contribution（current, voltage and welding speed） and the structural modifications produced during gas metal arc welding. The analysis comprises metallographic study,phase balance, dimensioning of the weld beads and tensile and hardness tests. The influence of the variables studied on the thermal cycles obtained（temperatures reached and cooling rate） was determined by using a finite element model. The results showed that, in addition to the indicated parameters, the parameter power transfer per volume（W/m3） and the geometry in the bead must be controlled due to their influence on the heat flow distribution and phase balance.

关键词： Welding Heat input GMAW Duplex stainless steels (DSS) Finite element model (FEM)

Is it growing exponentially fast? -Impact of assuming exponential growth for characterizing and forecasting epidemics with initial near-exponential growth dynamics

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Infectious Disease Modelling 2016年第1期1卷 71-78页

作者： gerardo Chowell Cecile Viboud School of Public Health Georgia State UniversityAtlantaGAUSA Division of International Epidemiology and Population Studies Fogarty International CenterNational Institutes of HealthBethesdaMDUSA

The increasing use of mathematical models for epidemic forecasting has highlighted the importance of designing models that capture the baseline transmission characteristics in order to generate reliable epidemic *** models for epidemic forecasting could be achieved by identifying signature features of epidemic growth,which could inform the design of models of disease spread and reveal important characteristics of the transmission *** particular,it is often taken for granted that the early growth phase of different growth processes in nature follow early exponential growth *** the context of infectious disease spread,this assumption is often convenient to describe a transmission process with mass action kinetics using differential equations and generate analytic expressions and estimates of the reproduction *** this article,we carry out a simulation study to illustrate the impact of incorrectly assuming an exponential-growth model to characterize the early phase(e.g.,3e5 disease generation intervals)of an infectious disease outbreak that follows near-exponential growth ***,we assess the impact on:1)goodness of fit,2)bias on the growth parameter,and 3)the impact on short-term epidemic *** findings indicate that devising transmission models and statistical approaches that more flexibly capture the profile of epidemic growth could lead to enhanced model fit,improved estimates of key transmission parameters,and more realistic epidemic forecasts.

关键词： dynamics. process. exponential

A primer on stable parameter estimation and forecasting in epidemiology by a problem-oriented regularized least squares algorithm

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Infectious Disease Modelling 2017年第2期2卷 268-275页

作者： Alexandra Smirnova gerardo Chowell Department of Mathematics and Statistics Georgia State UniversityAtlantaUSA School of Public Health Georgia State UniversityAtlantaUSA Division of International Epidemiology and Population Studies Fogarty International CenterNational Institutes of HealthBethesdaMDUSA

Public health officials are increasingly recognizing the need to develop disease-forecasting systems to respond to epidemic and pandemic *** instance,simple epidemic models relying on a small number of parameters can play an important role in characterizing epidemic growth and generating short-term epidemic *** the absence of reliable information about transmission mechanisms of emerging infectious diseases,phenomenological models are useful to characterize epidemic growth patterns without the need to explicitly model transmission mechanisms and the natural history of the *** this article,our goal is to discuss and illustrate the role of regularization methods for estimating parameters and generating disease forecasts using the generalized Richards model in the context of the 2014e15 Ebola epidemic in West Africa.

关键词： Generalized Richards model Parameter estimation Regularization methods Epidemic forecasting Ebola

Seismic hazard prediction using multispectral amplification maps in a complex topographic area: A case study of Qiaozhuang town, Sichuan Province, Southwest China

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Journal of Mountain Science 2022年第3期19卷 726-739页

作者： LUO Yong-hong XU Qiang ZHAN Wei-wei GRELLE gerardo State Key Laboratory of Geo-Hazard Prevention and Geo-Environment Protection Chengdu University of TechnologyChengdu 610059China Department of Civil and Environmental Engineering Tufts UniversityMedfordMA 02155USA Department of Civil and Environment Engineering University of RomeRome 00184Italy

Earthquakes can cause widely distributed slope failures and damage in mountainous *** accurate prediction of ground motions in mountainous areas is essential for managing the seismic risk of urban cities near mountains but is restricted primarily by complex seismic site amplification effects in areas of uneven *** study selected Qiaozhuang town located in the Qingchuan–Pingwu fault zone,Southwest China,as a case study.A simulator for mapped seismic responses using a hybrid model(Si Se RHMap)was applied to compute the multispectral seismic topographic amplification maps at the three slope units surrounding Qiaozhuang town(Weigan hill,***,and ***).Post-earthquake damage survey maps,1 D seismic site response spectral ratios,and H/V spectral ratios of earthquake data were used to validate the computed seismic site amplification factors and resonance *** results suggest that strong topographic amplification effects usually occur at distinct slope locations,such as hilltops,convex slope positions,upslope,and narrow *** computed topographic amplification factors in the study area reached up to 2.4 at upslope or hilltops,and the resonance frequencies were between 3 and 10 *** effects can be as important as stratigraphic effects when assessing seismic amplification effects in the study *** conclude that both topographic and stratigraphic effects should be considered in the comprehensive seismic hazard assessment of the study area or other similar mountain towns.

关键词： Seismic hazard prediction Multispectral amplification map topographic effects Stratigraphic effects SiSeRHMap Wenchuan earthquake

Positive frequency of autoantibodies in multiple sclerosis patients Are they associated with therapy?

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Neural Regeneration Research 2010年第4期5卷 257-260页

作者： gerardo Iuliano Luigi Cinquanta Anna Maria Ferruzzi Rosa Napoletano Azienda Ospedaliera Ospedali Riuniti di SalernoU.O.NeurologiaCentro Provinciale Sclerosi Multipla Azienda Ospedaliera Ospedali Riuniti di SalernoU.O.Laboratorio Patologia Clinica Azienda Ospedaliera Ospedali Riuniti di Salerno

BACKGROUND： Humoral autoimmunity in patients with multiple sclerosis is often asymptomatic and transient during interferon therapy. OBJECTIVE： To analyze the frequency of positivity to autoantibodies in multiple sclerosis patients and to clarify whether it is modified by immunomodulating therapy. DESIGN： A retrospective *** AND SE＇rrlNG： The study was performed at the Multiple Sclerosis Center, Department of Neurosciences, Salerno Hospital, Italy, between 2005 and 2007. PARTICIPANTS： A total of 169 multiple sclerosis patients were included, 57 males and 112 females Individuals were mainly outpatients and were usually tested yearly for autoantibodies. Patients with previous immunological diseases were excluded from statistical evaluation. METHODS： The frequency of positivity was calculated in patients grouped for gender, multiple sclerosis clinical parameters, magnetic resonance imaging features and disease modifying therapy. A total of 113 patients were treated with beta interferons. MAIN OUTCOME MEASURES： Frequency of positivity to any autoantibody. Prevalences and incidences were ***： The overall prevalence of autoantibodies within 3 years was 47.3%. In multiple sclerosis patients who were untreated or treated with drugs other than interferons, the prevalence was higher, and greater positivity to autoantibodies was seen in patients treated with interferons [odds ratio （95% confidence interval）, 2.87 （1.5 - 5.2）, P 〈 0.05 - 0.01]. Multiple regression analysis showed a significant association of the positivity to autoantibodies with interferon therapy, rather than gender, relapse or magnetic resonance imaging. CONCLUSION： Interferon therapy is associated with significantly higher frequency of autoantibodies in patients with multiple sclerosis. The differences among the therapies are not influenced by other variables such as gender or clinical pattern.

关键词： multiple sclerosis autoimmunity autoantibodies immunomodulation interferon

Focus on acute diarrhoeal disease

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World Journal of Gastroenterology 2009年第27期15卷 3341-3348页

作者： Fabio Baldi Maria Antonia Bianco gerardo Nardone Alberto Pilotto Emanuela Zamparo Gastroenterology Unit S. Orsola-Malpighi HospitalVia Massarenti 9 40138 Bologna Italy

Diarrhoea is an alteration of normal bowel movement characterized by an increase in the water content, volume, or frequency of stools. Diarrhoea needs to be classified according to the trends over time （acute or chronic） and to the characteristics of the stools （watery, fatty, inflammatory）. Secretory diarrhoeas, mostly acute and of viral aetiology in more than 70% of cases, are by far the most important subtype of diarrhoeas in terms of frequency, incidence and mortality （over 2.5 million deaths/year in developing countries）. Natural and synthetic opiates such as morphine, codeine, and Ioperamide which react with endogenous opiates （enkephalins, beta-endorphins, dynorphins） mainly act on intestinal motility and slow down transit. An antidiarrhoeal drug developed in recent years, racecadotril, acts as an enkephalinase inhibitor. Clinical studies have shown that it is just as effective as ioperamide in resolving acute diarrhoea but with greater reduction in pain and abdominal distension. Some studies have explored the prevalence of diarrhoea in old age. An epidemiological study carried out in Italy by 133 General Practitioners on 5515 elderly outpatients reported a prevalence of diarrhoea, defined according to the Rome criteria, of 9.1%. Infectious diseases （19%） and drug use （16%） were the most common causes of diarrhoea in old age. Regardless of the cause, the treatment of elderly patients with diarrhoea must include rehydration and nutritional support. Every year, more than 50 million tourists travel from industrialized countries to places where hygiene levels are pool. At least 75% of those travelling for short periods mention health problems, and in particular traveller＇s diarrhoea.

关键词： Diarrhoea Secretory diarrhoeas Elderly patients Traveller's diarrhoea Antidiarrhoeal drugs Enkephalinase inhibitor Racecadotril Efficacy Tolerability

Influence of steel jacket thickness on the RC bridges' seismic vulnerability

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第1期6卷 15-34页

作者： Bertha Olmos José Manuel Jara gerardo Gómez Guillermo Martínez Department of Civil Engineering Universidad Michoacana de San Nicolas de Hidalgo

The seismic demands of bridges subjected to strong earthquakes are mostly concentrated on piers. The main objective of this study is to assess the seismic vulnerability of retrofitted bridges with steel jackets. It analyzes the influence of the steel jacket thickness on the seismic capacity and demand of bridges. The bridges in study have two simple supported spans with superstructure composed by AASHTO type girders and a substructure formed with one circular pier over a stiff foundation. They are located on the Pacific coast of Mexico that is a zone of high seismicity. The bridges seismic capacity are evaluated through nonlinear static analyses and the shear force and displacement demands were determined using capacity spectra with a group of 10 real accelerograms from a subduction source. The response spectra were scaled to several peak ground accelerations(PGA) with the aim to estimate four damage scenarios linked each one to a probability of exceedance in a specific period, for return periods in the range of 72-3500 years that represent service level and maximum considered earthquake. Results show that the confining effect provided by the steel jackets substantially improves the seismic performance of the bridges piers. The increase of jacket thickness guides to important increments on columns base shear capacity, and the influence of the steel jacket thickness depends on the limit state and bridge slenderness ratio.

关键词： Steel jacket Piers’retrofit Subduction earthquakes RC piers’vulnerability

Effects of corn gluten feed inclusion at graded levels in a corn-soybean diet on the ileal and fecal digestibility of growing pigs

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Journal of Animal Science and Biotechnology 2015年第1期6卷 63-68页

作者： gerardo Mariscal Landin Tercia Cesaria Reis de Souza Ericka Ramirez Rodriguez Centro Nacional de Investigacion en Fisiologia Animal Instituto Nacional de Investigaciones Forestales Agricolas y PecuariasKm 1Carretera a ColonAjuchitlan ColonQueretaro 76280Mexico Facultad de Ciencias Naturales Universidad Autonoma de QueretaroSantiago de QueretaroAv.De las Ciencias s/n Juriquilla 76000QueretaroQueretaroMexico

Background： This study aimed to determine the effect of the inclusion of corn gluten feed （CGF） on the apparent and standardized ileal digestibility of protein and amino acids and the apparent ileal and total tract digestibility of energy in growing pigs. The study was performed using 16 barrows （weight, 45.3 ±4.5 kg） that were fitted with a T cannula at the terminal ileum. There were four treatments： a corn-soybean diet without CGF and three corn-soybean diets containing increasing levels of CGF （65, 130, and 195 g/kg）. Data were analyzed according to a randomized complete block design, four blocks with four pigs each （one pig per treatment）. The trend of the response （linear or quadratic） was determined using orthogonal contrasts, and when a linear effect was determined, a linear equation was obtained. Results： The results showed that the inclusion up to 195 g/kg of CGF in the corn-soybean diet did not diminish the ileal digestibility （apparent and standardized） of protein and amino acids （P 〉 0.05）, except that of phenylalanine, cystine, and proline. A linear decrease （P 〈 0.05） per gram of CGF added to the diet in the apparent and standardized ileal digestibility of phenylalanine （0.011 and 0.015 percentage units, respectively）, cystine （0.048 and 0.043 percentage units, respectively）, and proline （0.045 and 0.047 percentage units, respectively） was noted. Similarly, ileal digestibility of dry matter and energy were adversely affected （reduced by 0.028 and 0.025 percentage units, respectively, per gram of CGF increment in the diet）. A significant （P 〈 0.05） linear reduction in total tract digestibility with increase in CGF amount in the diet was observed for energy （0.027 percentage units）, dry matter （0.027 percentage units）, crude protein （0.020 percentage units）, and neutral detergent fiber （0.041 percentage units） per gram of CGF added to the diet. Conclusion： CGF did not affect the ileal digestibility of protein and most amino acids but reduced the ileal an

关键词： Amino acids Corn gluten feed Energy Ileal digestibility Pigs Total tract digestibility