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A simple model for fitting mild, severe, and known cases during an epidemic with an application to the current SARSCoV- 2 pandemic

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Infectious Disease Modelling 2021年第1期6卷 313-323页

作者： Matthew I.betti Jane M.Heffernan Mathematics and Computer Science Mount Allison UniversitySackvilleNew BrunswickCanada Mathematics and Statistics Centre for Disease ModellingYork UniversityTorontoOntarioCanada

One of the major difficulties with modelling an ongoing epidemic is that often data is limited or incomplete,making it hard to estimate key epidemic parameters and outcomes(e.***.attack rate,peak time,reporting rate,reproduction number).In the current study,we present a model for data-fitting limited infection case data which provides estimates for important epidemiological parameters and outcomes.The model can also provide reasonable short-term(one month)projections.We apply the model to the current and ongoing COVID-19 outbreak in Canada both at the national and provincial/territorial level.

关键词： Basic reproduction number Epidemic curve fitting COVID-19 Other words

Comparison of dosimetry with magnetic resonance and computed tomography imaging delineation of surgical bed volume in breast cancer irradiation

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Cancer Pathogenesis and Therapy 2023年第1期1卷 12-17页

作者： M.betti L.C.Orlandini C.Biagini M.De Liguoro L.Cionini Medical Physics Department Centro Oncologico Fiorentino50019Sesto Fiorentino(FI)Italy Medical Physics Department PistoiaAzienda USL Toscana Centro51100Pistoia(PT)Italy Radiation Oncology Department Sichuan Cancer Hospital&Research InstituteChengduSichuan 610041China Diagnostic Department Diagnostic Institute Santo Stefano59100Prato(PO)Italy Radiation Oncology Department Azienda sanitaria Locale Asti14100Asti(AT)Italy Radiation Oncology Department Centro Oncologico Fiorentino50019Sesto Fiorentino(FI)Italy

Background Postoperative radiotherapy after conservative surgery for patients with breast cancer usually includes focal over-irradiation(boost)to the surgical bed(SB).Irradiation planning using computed tomography(CT)is difficult in many cases because of insufficient intrinsic soft tissue contrast.To ensure appropriate radiation to the tumor,large boost volumes are delineated,resulting in a higher dose to the normal tissue.Magnetic resonance imaging(MRI)provides superior soft tissue contrast than CT and can better differentiate between normal tissue and the SB.However,for SB delineation CT images alone remain the pathway followed in patients undergoing breast irradiation.This study aimed to evaluate the potential advantages in boost dosimetry by using MRI and CT as pre-treatment imaging.Methods Eighteen boost volumes were drawn on CT and MRI and elastically co-registered using commercial image registration software.The radiotherapy treatment plan was optimized using the CT volumes as the baseline.The dose distributions of the target volumes on CT and MRI were compared using dose-volume histogram cutoff points.Results The radiation volumes to the SB varied considerably between CT and MRI(conformity index between 0.24 and 0.67).The differences between the MRI and CT boost doses in terms of the volume receiving 98%of the prescribed dose(V98%)varied between 10%and 30%.Smaller differences in the V98%were observed when the boost volumes were delineated using MRI.Conclusion Using MRI to delineate the volume of the SB may increase the accuracy of boost dosimetry.

关键词： Breast radiotherapy MRI Boost delineation Seroma Dosimetry

Differential responses to artificial selection on oviposition site preferences in Drosophila melanogaster and D. simulans

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Insect Science 2015年第6期22卷 821-828页

作者： Eduardo M. Soto Maria I. L. betti Juan Hurtado Esteban Hasson Departamento de Ecologia Genetica y Evolucion IEGEBA (CONICET-UBA) Facultad de Ciencias Exactas y Naturales Universidad deBuenos Aires Buenos Aires Argentina

The preference-performance relationship in plant-insect interactions is a cen- tral theme in evolutionary ecology. Among many insects, eggs are vulnerable and larvae have limited mobility, making the choice of an appropriate oviposition site one of the most important decisions for a female. We investigated the evolution of oviposition preferences in Drosophila melanogaster Meigen and Drosophila simulans Sturtevant by artificially selecting for the preference for 2 natural resources, grape and quince. The main finding of our study is the differential responses of D. melanogaster and D. simulans. Although preferences evolved in the experimental populations of D. melanogaster, responses were not consistent with the selection regimes applied. In contrast, responses in D. simulans were consistent with expectations, demonstrating that this species has selectable genetic variation for the trait. furthermore, crosses between D. simulans divergent lines showed that the genetic factors involved in grape preference appear to be largely recessive. In summary, our artificial selection study suggests that D. melanogaster and D. simulans possess different genetic architectures for this trait.

关键词： artificial selection behavior Drosophila genetic variation naturalresources oviposition preference

Gene expression and physiological responses to salinity and water stress of contrasting durum wheat genotypes

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Journal of Integrative Plant Biology 2016年第1期58卷 48-66页

作者： Salima Yousfi Antonio J.Marquez Marco betti Jose Luis Araus Maria Dolores Serret Unit of Plant Physiology Department of Plant BiologyFaculty of BiologyUniversity of Barcelona08028Spain Department of Plant Biochemistry and Molecular Biology Faculty of ChemistryUniversity of SevilleSevilla 41012Spain

Elucidating the relationships between gene expression and the physiological mechanisms remains a bottleneck in breeding for resistance to salinity and drought. This study related the expression of key target genes with the physiological performance of durum wheat under different combinations of salinity and irrigation. The candidate genes assayed included two encoding for the DREB（dehydration responsive element binding） transcription factors Ta DREB1 A and Ta DREB2 B, another two for the cytosolic and plastidic glutamine synthetase（Ta GS1 and Ta GS2）, and one for the specific Na^＋/H^＋ vacuolar antiporter（Ta NHX1）. Expression of these genes was related to growth and different trait indicators of nitrogen metabolism（nitrogen content, stable nitrogen isotope composition, and glutamine synthetase and nitrate reductase activities）, photosynthetic carbon metabolism（stable carbon isotope composition and different gas exchange traits） and ion accumulation. Significant interaction between genotype and growing conditions occurred for growth, nitrogen content, and the expression of most genes.In general terms, higher expression of Ta GS1, Ta GS2,Ta DREB2 B, and to a lesser extent of Ta NHX1 were associated with a better genotypic performance in growth, nitrogen, and carbon photosynthetic metabolism under salinity and water stress. However, Ta DREB1 A was increased in expression under stress compared with control conditions, with tolerant genotypes exhibiting lower expression than susceptible ones.

关键词： Durum wheat （Triticum turgidum ssp. durum） geneexpression nitrogen metabolism salinity stable isotope

Environmental control of rice flowering time

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Plant Communications 2023年第5期4卷 134-152页

作者： Giulio Vicentini Marco Biancucci Lorenzo Mineri Daniele Chirivı francesca Giaume Yiling Miao Junko Kyozuka Vittoria Brambilla Camilla betti fabio fornara Department of Biosciences University of Milanvia Celoria 2620133 MilanItaly Department of Agricultural and Environmental Sciences University of Milanvia Celoria 220133 MilanItaly Graduate School of Life Sciences Tohoku UniversitySendaiJapan

Correct measurement of environmental parameters is fundamental for plant fitness and survival,as well as for timing developmental transitions,including the switch from vegetative to reproductive growth.Important parameters that affect flowering time include day length(photoperiod)and temperature.Their response pathways have been best described in Arabidopsis,which currently offers a detailed conceptual framework and serves as a comparison for other species.Rice,the focus of this review,also possesses a photoperiodic flowering pathway,but 150 million years of divergent evolution in very different environments have diversified its molecular architecture.The ambient temperature perception pathway is strongly intertwined with the photoperiod pathway and essentially converges on the same genes to modify flowering time.When observing network topologies,it is evident that the rice flowering network is centered on EARLY HEADING DATE 1,a rice-specific transcriptional regulator.Here,we summarize the most important features of the rice photoperiodic flowering network,with an emphasis on its uniqueness,and discuss its connections with hormonal,temperature perception,and stress pathways.

关键词： rice photoperiod temperature flowering stress florigens

地震荷载下罗马式教堂的模型与分析:抗震能力评估

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钢结构 2008年第8期23卷 79-80页

作者： Michele betti Andrea Vignoli

分析罗马式砌体教堂以评估其结构性能及地震脆性,从一个特殊案例出发,提供了纪念碑砌体建筑在地震作用下的模型和分析的结果。采用有限元方法对传统的砌体结构进行静态和动态非线性分析并应用于案例研究。采用拟静态方法(地震系数法)评... 详细信息

分析罗马式砌体教堂以评估其结构性能及地震脆性,从一个特殊案例出发,提供了纪念碑砌体建筑在地震作用下的模型和分析的结果。采用有限元方法对传统的砌体结构进行静态和动态非线性分析并应用于案例研究。采用拟静态方法(地震系数法)评估地震荷载(事实上很多砌体结构地震性能的分析是相同的),与承载力的对比证实这类建筑大规模的损坏以及可能的坍塌正如经常被观察到的那样。此外,分析了当前修复和加固技术的实际效率,以评估其效益。对修复和加固技术的分析显示,提高抗震能力,增强了对普通结构加固的效果。提倡从先进的数字分析来获得重要的信息。即关于对既有破坏的理解、对最小加固量和适当加固设计的理解。基于结构分析的复杂工具,对结构性能和可靠加固的清晰理解能减少古代结构修复补救的范围。

关键词：罗马式教堂建筑地震荷载非线性分析有限元模型地震脆性加固技术

Human cytomegalovirus and Epstein-Barr virus infection in inflammatory bowel disease:Need for mucosal viral load measurement

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World Journal of Gastroenterology 2015年第6期21卷 1915-1926页

作者： Rachele Ciccocioppo francesca Racca Stefania Paolucci Giulia Campanini Lodovica Pozzi Elena betti Roberta Riboni Alessandro Vanoli fausto Baldanti Gino Roberto Corazza Centre for the Study and Cure of Inflammatory Bowel Disease Clinica Medica I IRCCS San Matteo Hospital Foundation University of Pavia SS Virologia Molecolare - SC Virologia e Microbiologia Fondazione IRCCS Policlinico San Matteo Servizio di Endoscopia Digestiva Fondazione IRCCS Policlinico San Matteo Servizio di Anatomia Patologica fondazione IRCCS Policlinico San Matteo

AIM:To evaluate the best diagnostic technique and risk factors of the human Cytomegalovirus(HCMV)and Epstein-Barr virus(EBV)infection in inflammatory bowel disease(IBD).METHODS:A cohort of 40 IBD patients(17 refractory)and 40 controls underwent peripheral blood and endoscopic colonic mucosal sample harvest.Viral infection was assessed by quantitative real-time polymerase chain reaction and immunohistochemistry,and correlations with clinical and endoscopic indexes of activity,and risk factors were investigated.RESULTS:All refractory patients carried detectable levels of HCMV and/or EBV mucosal load as comparedto 13/23(56.5%)non-refractory and 13/40(32.5%)controls.The median DNA value was significantly higher in refractory(HCMV 286 and EBV 5.440 copies/105cells)than in non-refractory(HCMV 0 and EBV 6copies/105 cells;Pfor both).Refractory patients showed DNA peak values≥103 copies/105 cells in diseased mucosa in comparison to non-diseased mucosa(Pfor HCMV andfor EBV),while non-refractory patients and controls invariably displayed levels below this threshold,thus allowing us to differentiate viral colitis from mucosal infection.Moreover,the mucosal load positively correlated with the values found in the peripheral blood,whilst no correlation with the number of positive cells at immunohistochemistry was found.Steroid use was identified as a significant risk factor for both HCMV(P=0.018)and EBV(P=0.002)colitis.finally,a course of specific antiviral therapy with ganciclovir was successful in all refractory patients with HCMV colitis,whilst refractory patients with EBV colitis did not show any improvement despite steroid tapering and discontinuation of the other medications.CONCLUSION:Viral colitis appeared to contribute to mucosal lesions in refractory IBD,and its correct diagnosis and management require quantitative real-time polymerase chain reaction assay of mucosal specimens.

关键词： Inflammatory bowel disease quantitative real-time

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青蛙也敢吃恐龙

小哥白尼（趣味科学） 2008年第8期 28-29页

作者：朱芳芳 Luci betti-Nash

听说最近马达加斯加岛又发生了大事,古生物学家们根据一种青蛙化石得出了一个耸人听闻的推论——在远古的白垩纪时期,有一种青蛙可以吃掉小恐龙。哇,什么青蛙有这么大的能耐?小昆昆决定坐着世间旅行机器去白垩纪看一看。

关键词：马达加斯加青蛙恐龙蛋古生物学家白垩纪战术家伙草丛埋伏化石

Evaluating the Role of Governance in the Management of Prunus africana (Hook.f.) Kalkman in the Adamawa Region of Cameroon

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Open Journal of forestry 2022年第4期12卷 408-431页

作者： Steve Nanfack Tassiamba Jean Lagarde betti Lucie félicité Temgoua Liliane Rosine Kourogue Armand Wilfried Ndedy Bile Alain Rayane Mpouam Department of forestry Faculty of Agronomy and Agricultural Sciences University of Dschang Dschang Cameroon faculty of Science Department of Biology and Physiology of Plant Organisms University of Douala Douala Cameroon

One of the problems at the root of the poor management of forest resources in Cameroon is the lack of good governance. This study aims to evaluate the governance put in place by the government of Cameroon to ensure better management of Prunus africana. It takes a critical look at the three pillars of forest governance in relation to the management of the resource, which are: policy, legal, institutional and regulatory frameworks (1);planning and decision-making process (2);and finally the implementation, enforcement and compliance of regulations (3). The assessment was conducted using the guide recommended by fAO-PROfOR. Individual and focus group interviews were conducted with stakeholders involved in the P. africana management process. The results in the form of assessment scores revealed poor governance in the management of the resource. This is due to non-compliance with Pillars 2 and 3 on the planning and decision-making process as well as the implementation and enforcement of regulations through weaknesses in the principles of transparency, accountability, the effectiveness of management measures and stakeholder participation. These are the points on which management strategies should be based for better management of P. africana in the production forests of the Adamawa region.

关键词： forest Governance Prunus africana Stakeholders Pillars Components