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Epidemics on networks: Reducing disease transmission using health emergency declarations and peer communication

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Infectious Disease Modelling 2020年第1期5卷 12-22页

作者： Asma Azizi cesar Montalvo Baltazar Espinoza Yun Kang Carlos Castillo-Chavez School of Human Evolution and Social Change Simon A.Levin Mathematical Computational Modeling Science CenterArizona State UniversityTempeAZ85281USA Division of Applied Mathematics Brown UniversityProvidenceRI02906USA Sciences and Mathematics Faculty College of Integrative Sciences and ArtsArizona State UniversityMesaAZ85212USA

Understanding individual decisions in a world where communications and information move instantly via cell phones and the internet,contributes to the development and implementation of policies aimed at stopping or ameliorating the spread of diseases.In this manuscript,the role of official social network perturbations generated by public health officials to slow down or stop a disease outbreak are studied over distinct classes of static social networks.The dynamics are stochastic in nature with individuals(nodes)being assigned fixed levels of education or wealth.Nodes may change their epidemiological status from susceptible,to infected and to recovered.Most importantly,it is assumed that when the prevalence reaches a pre-determined threshold level,P*,information,called awareness in our framework,starts to spread,a process triggered by public health authorities.Information is assumed to spread over the same static network and whether or not one becomes a temporary informer,is a function of his/her level of education or wealth and epidemiological status.Stochastic simulations show that threshold selection Pand the value of the average basic reproduction number impact the final epidemic size differentially.For the ErdÖos-Rényi and Small-world networks,an optimal choice for Pthat minimize the final epidemic size can be identified under some conditions while for Scalefree networks this is not case.

关键词： Awareness spread Behavior change Outbreak and epidemic threats ErdÖos-rényi network Small-world network Scale-free network

Spatio-temporal co-occurrence of hotspots of tuberculosis, poverty and air pollution in Lima, Peru

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Infectious Diseases of Poverty 2020年第2期9卷 84-89页

作者： Gabriel Carrasco-Escobar Alvaro Schwalb Kelly Tello-Lizarraga Percy Vega-Guerovich cesar Ugarte-Gil Health Innovation Lab Instituto de Medicina Tropical Alexander von HumboldtUniversidad Peruana Cayetano HerediaLimaPeru Division of Infectious Diseases Department of MedicineUniversity of California San DiegoLa JollaCAUSA Instituto de Medicina Tropical Alexander von Humboldt Universidad Peruana Cayetano HerediaLimaPeru School of Public Health and Administration Universidad Peruana Cayetano HerediaLimaPeru School of Economics and Finance Universidad del PacificoLimaPeru School of Medicine Universidad Peruana Cayetano HerediaLimaPeru TB Centre London School of Hygiene and Tropical MedicineLondonUK

Growing evidence suggests pollution and other environmental factors have a role in the development of tuberculosis(TB),however,such studies have never been conducted in Peru.Considering the association between air pollution and specific geographic areas,our objective was to determine the spatial distribution and clustering of TB incident cases in Lima and their co-occurrence with clusters of fine particulate matter(PM2.5)and poverty.We found co-occurrences of clusters of elevated concentrations of air pollutants such as PM2.5,high poverty indexes,and high TB incidence in Lima.These findings suggest an interplay of socio-economic and environmental in driving TB incidence.

关键词： Tuberculosis Hotspots Air pollution

Foodborne outbreaks in Brazil associated with fruits and vegetables:2008 through 2014

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Food Quality and Safety 2018年第4期2卷 173-181页

作者： Susana de Oliveira Elias Luana Tombini Decol Eduardo cesar Tondo Departamento de Ciências dos Alimentos-Universidade Federal do Rio Grande do Sul Instituto de Ciência e Tecnologia de Alimentos-Av.Bento Gonçalves9500 Prédio 43212 Agronomia CEP:91505-970-Porto Alegre-RS-Brasil

Objectives:Foodborne disease outbreaks linked to fruits and vegetables have been increasing in occurrence worldwide;therefore,the aim of this study was to identify the reported foodborne outbreaks associated with fruit and vegetable consumption in Brazil from 2008 to 2014.Results And Limitations:Thirty produce related outbreaks resulted in 2926 illnesses,347 hospitalizations,and no deaths.Only bacterial pathogens were identified as etiological agents.Among these,Salmonella was the most frequent(30 per cent of outbreaks)followed by Staphylococcus aureus(23.3 per cent),Escherichia coli(10 per cent),Bacillus cereus(6.6 per cent),and thermotolerant coliforms(3.3 per cent),whereas etiological agents could not be determined for 26.6 per cent of outbreaks.The most common food vehicles implicated in outbreaks were generically named as fruits and vegetables(46.6 per cent of outbreaks).The term salad was used generically and specifically like salads(two outbreaks),raw/cooked salads(four outbreaks),vegetable salad,tropical salad,Caesar salad,and raw salad of cabbage and tomato.Only one outbreak was related exclusively to fruit(fruit pulp),whereas other outbreaks were related to cooked carrot,lettuce,cucumber,watermelon/cabbage,and chard/beet.Contamination sources and issues related to the future control of produce-related foodborne disease outbreaks are discussed.

关键词： produce pathogens Salmonella foodborne illness disease surveillance notification

Quantitative genetic analysis of chlorophyll a fluorescence parameters in maize in the field environments

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Journal of Integrative Plant Biology 2014年第7期56卷 695-708页

作者： Domagoj ?imi? Hrvoje Lepedu? Vlatka Jurkovi? Jasenka Antunovi? Vera cesar Agricultural Institute Osijek Faculty of Humanities and Social Sciences Department of Biology Josip Juraj Strossmayer University of Osijek

Chlorophyl fluorescence transient from initial to maximum fluorescence （“P”step） throughout two intermedi-ate steps （“J”and“I”）（JIP-test） is considered a reliable early quantitative indicator of stress in plants. The JIP-test is particularly useful for crop plants when applied in variable field environments. The aim of the present study was to conduct a quantitative trait loci （QTL） analysis for nine JIP-test parameters in maize during flowering in four field environ-ments differing in weather conditions. QTL analysis and identification of putative candidate genes might help to explain the genetic relationship between photosynthesis and different field scenarios in maize plants. The JIP-test param-eters were analyzed in the intermated B73 ？ Mo17 （IBM） maize population of 205 recombinant inbred lines. A set of 2,178 molecular markers across the whole maize genome was used for QTL analysis revealing 10 significant QTLs for seven JIP-test parameters, of which five were co-localized when combined＆amp;nbsp;over the four environments indicating polygenic inheritance and pleiotropy. Our results demonstrate that QTL analysis of chlorophyl fluorescence parameters was capable of detecting one pleiotropic locus on chromosome 7, coinciding with the gene gst23 that may be associated with efficient photosynthe-sis under different field scenarios.

关键词： Chlorophyll a fluorescence parameters field conditions intermated B73× Mo17 recombinant inbred lines JIP-test maize （Zeamays L.） quantitative trait loci

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带投资约束p-中位问题的混合蚁群算法

计算机应用研究 2017年第6期34卷 1704-1707,1725页

作者：李倩张惠珍 cesar Beltran-Royo 上海理工大学管理学院上海200093 胡安卡洛斯大学统计与运筹系西班牙马德里28001

将投资限制引入经典约束p-中位问题,提出带投资的约束p-中位问题,该问题更适用于交通、物流等领域的设施选址。在深入分析带投资约束p-中位问题的数学模型的基础上,首先提出了适用于该问题求解的局部搜索策略;其次,将局部搜索策略与拉... 详细信息

将投资限制引入经典约束p-中位问题,提出带投资的约束p-中位问题,该问题更适用于交通、物流等领域的设施选址。在深入分析带投资约束p-中位问题的数学模型的基础上,首先提出了适用于该问题求解的局部搜索策略;其次,将局部搜索策略与拉格朗日启发式算法和蚁群算法相结合,设计了求解该问题的拉格朗日混合蚁群算法。实验结果表明,带投资的约束p-中位问题能够根据投资金额规划不同的投资方案;且提出的混合蚁群算法较大程度上提高了蚁群算法和拉格朗日启发式算法的求解精度,具有较好的收敛性。

关键词：拉格朗日启发式蚁群算法局部搜索约束p-中位问题

Modified activated carbon with interconnected fibrils of iron-oxyhydroxides using Mn^(2+) as morphology regulator, for a superior arsenic removal from water

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Journal of Environmental Sciences 2019年第2期31卷 403-414页

作者： cesar Nieto-Delgado Joel Gutiérrez-Martínez J.Rene Rangel-Méndez Environmental Sciences Division Potosino Institute of Scientific and Technological ResearchIPICyT

The arsenic removal efficiency of iron-modified activated carbons depends greatly on the number of available iron oxide surface sites, which are given by the surface area of the anchored particles. In this sense, aiming the generation of an adsorbent with superior arsenic adsorption capacity, we developed a protocol to anchor interconnected fibrils of iron oxyhydroxides, using Mn^(2+) as a morphology regulator. The protocol was based on a microwave-assisted hydrothermal method, using bituminous based activated carbon and both Fe^(2+) and Mn^(2+) ions in the hydrolysis solution. The elemental analysis of modified carbons revealed that Mn does not anchor to the carbon. However, when Mn is included in the hydrolysis solution, the iron content in the activated carbon increased up to 3.5 wt%,without considerable decreasing the adsorbent surface area. Under specific hydrothermal conditions, the Mn^(2+) promoted the formation of iron oxide nanoparticles shaped as interconnected fibrils. This material showed a superior arsenic adsorption capacity in comparison to similar iron modified activated carbons(5 mg As/g carbon, at 2 mg As/L),attributed to the increase in quantity and availability of active sites located on the novel interconnected fibrils of iron oxyhydroxides nanostructures.

关键词： Iron oxide nanostructures Hydrothermal synthesis Microwave Adsorption capacity Kinetics

Abiotic stress on seed germination and plant growth of Zeyheria tuberculosa

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林业研究:英文版 2023年第5期34卷 1511-1522页

作者： Robson Luis Silva de Medeiros Rinaldo cesar de Paula Joao Vitor Oliveira de Souza Joao Pedro Peixoto Fernandes Department of Agricultural Sciences School of Agricultural and Veterinarian SciencesSao Paulo State University(Unesp)14884-900JaboticabalSao PauloBrazil

Zeyheria tuberculosa(Vell.)Bureau ex Verl.is among the Brazilian flora threatened with extinction.It has high-quality wood and can be used to recover herbicidecontaminated areas.However,abiotic stresses can harm seed germination and seedling development under adverse conditions and need to be understood to improve autochthonous or indigenous biodiversity conservation and strengthen reforestation projects.This study evaluated the effects of temperature,water and saline stress on Z.tuberculosa seed germination and water stress on seedling growth.Three laboratory experiments evaluated germination under:(1)different temperatures(20,25,30,35 and 40℃);(2)different water potentials simulated with polyethylene glycol(PEG6000)at 25 and 30℃;and,(3)different osmotic potentials simulated with NaCl at 25 and 30℃.In addition,a greenhouse experiment subjected seedlings to five water regimes(20%,35%,50%,65%and 80%of maximum substrate water holding capacity).In the laboratory,seedling biometry and germination were evaluated,while physiological and morphological parameters were assessed in the greenhouse.Physiological potential of seeds increased at 25 and 30℃.Germination and vigor decreased as water and saline stresses increased.Germination tolerance thresholds for water and salt stresses were-0.6 and-0.4 MPa,respectively.In the greenhouse,the most restrictive water regimes reduced seedling physiological and morphological parameters.Seedling development was compromised at moisture levels below50%field capacity.

关键词： Bignoniaceae Climate change Ipê-felpudo Ipê-preto Water stress

阿根廷内乌肯盆地瓦卡穆尔塔组非常规垂直井水力裂缝高度估计——利用时间推移声波测井和非放射性Oarbo NRT支撑剂方法可以估算裂缝高度

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世界石油工业 2017年第3期24卷 58-63页

作者： Alberto cesar Ortiz 雷普索尔石油公司

自2010年以来，瓦卡穆尔塔组就成为阿根廷非常规油气开采最重要的储集层段。这个储集层位于内乌肯盆地，该层段由25-450m厚的富含有机质的页岩和泥灰岩组成。储集层如此厚是开发这个层段所面临的重大挑战之一，然而通过测量水力压裂在... 详细信息

自2010年以来，瓦卡穆尔塔组就成为阿根廷非常规油气开采最重要的储集层段。这个储集层位于内乌肯盆地，该层段由25-450m厚的富含有机质的页岩和泥灰岩组成。储集层如此厚是开发这个层段所面临的重大挑战之一，然而通过测量水力压裂在垂向和横向上的效果可以减少这种不确定性。

关键词：阿根廷非放射性声波测井时间推移高度估计水力裂缝裂缝高度盆地

Soot combustion; Ceria; Ternary mixed oxide; Cordierite coating; Diesel particulate filter

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Journal of Environmental Sciences 2018年第11期30卷 58-68页

作者： Leandro Fontanetti Nascimento Juliana Fonseca Lima Paulo cesar de Sousa Filho Osvaldo Antonio Serra Department of Chemistry FFCLRP University of Sao Paulo 14040-901 Ribeirao Preto Sao Paulo Brazil Institute of Chemistry Rio de Janeiro State University 20550-900 Rio de Janeiro Rio de Janeiro Brazil Institute of Chemistry Uniuersity of Campinas 13083-970 Campinas Silo Paulo Brazil Center of-Natural and Human Sciences Federal Uniuerty of ABC 09210-580 Santo Andre Sao Paulo Brazil

We report the application of a solid lanthanum-ceria-zinc catalyst in the catalytic regeneration of diesel particulate filters （DPF） in diesel engines. We synthesized a CeO2- ZnO-La2O3 （Ce-Zn-La） mixed oxide by a lactic acid-mediated sol-gel method, which efficiently coated cordierite substrates for soot capture and combustion. We studied the effects of La loading on the physicochemical and catalytic properties of Ce-Zn mixed oxide during lowtemperature soot combustion processes. We characterized the synthesized catalysts by X-ray diffraction （XRD）, Fourier-transform infrared spectroscopy （FTIR）, N2 adsorption, Raman spectroscopy, oxygen storage capacity （OSG）, and scanning and transmission electron microscopy （SEM and TEM）. Thermogravimetric and differential thermal analysis （TGA/DTA） confirmed that the catalysts effectively reduced the soot oxidation temperature. The ternary Ce-Zn-La mixed oxide catalyst with Ce/Zn/La atomic ratio of 2：1：0.5 had the highest catalytic activity and promoted soot oxidation at temperatures below 390℃. This indicated that the large number of oxygen vacancies in the catalyst structure generated oxygen species at low temperatures. Raman spectroscopy measurements revealed the presence of oxygen vacancies and lattice defects in Ce-Zn-La samples, which were key parameters concerning the stability and redox properties of the prepared catalysts.

关键词： Soot combustion Ceria Ternary mixed oxide Cordierite coating Diesel particulate filter