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Monte Carlo Simulations for a Preliminary Design of TRIGA IPR-R1 PGAA Facility

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Journal of Chemistry and Chemical Engineering 2016年第6期10卷 256-270页

作者： Bruno Teixeira Guerra Alexandre Soares Leal Claubia Pereira maria angela de Barros Correia Menezes DEN (Departamento de Engenharia Nuclear) UFMG (Universidade Federal de Minas Gerais) Av. Antonio Carlos 6627 Campus Pampulha CEP 31270 901 Belo Horizonte Minas Gerais Brazil CDTN (Nuclear Technology Development Center) CNEN (Brazilian Commission for Nuclear Energy) Av. Antonio Carlos 6627 Campus UFMG CEP 31270 901 Belo Horizonte Minas Gerais Brazil

In this paper, the evaluation of a preliminary design of a PGAA （prompt gamma activation analysis） facility based on Monte Carlo simulations is presented and discussed. The implementation of the PGAA method at the CDTN （nuclear technology development centre） would increase the applications of the TRIGA reactor. The preliminary design is based on a quasi vertical hollow cylinder （called neutron extractor） in the reactor pool to extract the neutron flux. This study evaluates the neutron flux in the upper position of the cylinder in the suggested position of the samples to be analyzed by the PGAA. The calculations of the radioactive capture reaction rates and of the detection limits for some isotopes were performed. Through all these calculations, the feasibility of the application of the PGAA method at the IPR-R1 installations was evaluated. According to the obtained results, it can be concluded that is possible to apply the PGAA method at the IPR-R1 reactor, even with its design restrictions.

关键词： PGAA facility neutron activation analysis TRIGA IPR-R1 PGAA NAA.

Long-lasting effects of unplanned logging on the seed rain of mixed conifer-hardwood forests in southern South America

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Journal of Forestry Research 2021年第4期32卷 1409-1418页

作者： Alexandre F.Souza angela Luciana deÁvila Maristela M.Araújo Solon Jonas Longhi Departament of Ecology CBRio Grande Do Norte Federal UniversityCentral CampusLagoa NovaNatal 59072-970RNBrazil Forest Growth Department Freiburg Im BreisgauBaden-Vurtemberga Forest Research InstituteWonnhaldestraße 4Freiburg im Breisgau 79104Germany Forest Engineering Postgraduate Program Forestry DepartmentSanta Maria Federal UniversityRoraima Av.s/nCamobiSanta Maria 97105-900RSBrazil

Understanding the effects of disturbance on seed rain is critical to predict changes in forest species composition and *** effects on seed rain in a mixed conifer-hardwood forest complex in southern Brazil were *** year of seed rain data were collected from a large-scale observational experiment in logged and protected forests and quantity and average seed size weighted by species abundance(CWM)were compared between old-growth and logged stands 55 years after logging *** these data,variations in frequency of functional groups of species in the seed rain were examined to see if they could be attributed to *** show that the number of seeds per trap was highly right-skewed,ranging from 13 to 12,788 seeds per trap in one *** rain was affected by logging history,with seed traps in old-growth plots receiving significantly less seeds than traps in logged *** species included mean seed size weighted by species abundance were significantly smaller in logged than in old-growth *** difference persisted after the exclusion of Arawcaria a large-seeded pioneer which was intensively logged,although the difference of seed size between the two forest classes was greatly *** abundance in the seed rain differed significantly from the established tree community,between logged and oldgrowth *** composition of the seed rain was much more variable than the composition of the established tree community and its points more scattered over the ordination space than the points corresponding to the protected *** number of collected seeds across different functional groups of species significantly differed between logged and old-growth *** seed rain of logged forests reflects their arrested succes sion as indicated by reduced abundance of functional groups such as pioneers,large seeded pioneers and A raucaria,as well as reduced functional diversity.S eed rain differences between logged and old-

关键词： Arrested succession Brazil Logging Long-lived pioneers Seed rain

Development and Evaluation of a Competence-BasedExam for Prospective Driving Instructors

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Journal of Traffic and Transportation Engineering 2015年第3期3卷 147-157页

作者： Erik C. Roelofs maria Bolsinova angela Verschoor Jan A. M. M. Vissers Measurement and Research Department Cito Arnhem 1034 the Netherlands Unit Transport Royal HaskoningDHV Amersfoort 1132 the Netherlands

According to changed views on driver training and driverintroduced in the Netherlands. The exam consists of two parts：（l）instructor preparation, a competence-based instructor exam wasmultimedia theory tests; （2） a performance lesson for drivinginstruction and coaching. An implicit idea behind the innovated exam is that it can have a positive backwash effect on the quality ofdriver instructor preparation programs. This study aims to evaluate the reliability, validity and fairness of the theoretical tests, whichappear in different versions for successive groups of PDIs （prospective driving instructors）. Data of 4,741 PDIs, enrolled during theperiod between January 2010 and October 2012, were used for analysis. The results of psychometric analyses show that the theory testsyielded reliable and fair decisions about instructor certification. The predictive validity of the theory tests for the final performanceassessment was low. Implications for the design and on-the-fly maintenance of exam item banks are discussed. Follow-up studies willfocus on the question, whether the improved instructor exam produces safer drivers in the end.

关键词： Prospective driving instructors, evidence centered design, validity, competence-based exams.

Signaling Networks Controlling HCC Onset and Progression: Influence of Microenvironment and Implications for Cancer Gene Therapy

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Journal of Cancer Therapy 2013年第2期4卷 353-358页

作者： Alessandra Marchetti Carla Cicchini Laura Santangelo angela maria Cozzolino Viviana Costa Marco Tripodi Laura Amicone Pasteur Institute—Cenci Bolognetti Foundation Department of Cellular Biotechnologies and Hematology Sapienza University Rome Italy

Hepatocarcinogenesis, as other epithelial malignancies, has been proved to be a multistep process that, starting from mutagenic events, allows the transformed liver cell to evolve towards a more aggressive phenotype, characterized by the acquisition of migratory/invasive and stem-cell-like properties. Hepatocellular carcinoma(HCC)can originate from both mature hepatocytes and liver precursor/stem cells. Whatever its origin, a common feature of advanced-stage HCC is the reduction or lack of expression of master genes of epithelial/hepatocyte differentiation, i.e. members of the liver enriched transcription factors(LEFTs)family like HNF4α, and conversely an increased expression of epithelial-to-mesenchymal transition(EMT)master genes, i.e. the transcriptional repressors belonging to the Snail family. Recently, it has emerged as members of these families are capable to directly repress each other and to regulate in opposite manner target genes involved in stemness and in hepatocyte differentiation, thus influencing cell outcome between epithelial/differentiated/poor aggressive and mesenchymal/undifferentiated/aggressive phenotype. Consequently, the restoration of LEFT functions in invasive HCC could represent an important goal for anti-cancer therapies. However, any strategy based on gene transfer needs to take in account the influence of micro-environmental factors in HCC tumor niche, like TGFb, responsible for shifting the described balance in tumor cell towards the acquisition of stem-cell like properties and invasiveness, through Snail/EMT induction and LEFTs downregulation. The presence of this cytokine, indeed, was shown to override both anti-EMT and tumor suppressor activity of the ectopically expressed HNF4α protein. In this review, the rationale to propose implementation of HCC gene therapy will be discussed.

关键词： HNF4 Snail TGFβ microRNA EMT Cancer Stem Cell

Messages from the Border: Novel Insights in Signal Transduction Pathways Involved in Tumor Invasion and Metastasis

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Journal of Cancer Therapy 2015年第2期6卷 199-212页

作者： Michele Ciccarelli mariarosaria Rusciano Daniela Sorriento angela Serena Maione maria Soprano Guido Iaccarino Maddalena Illario Department of Medicine and Surgery University of Salerno Salerno Italy Department of Clinical and Translational Medicine Federico II University Napoli Italy IBP CNR Napoli Italy IOS e Coleman Napoli Italy

Cancer is a multistep process encompassing the transformation of normal epithelial cells to the stromal invasion and metastasis, with these last considered the final stage of the disease. Tumor invasiveness is based on creation of a specific peri-tumoral environment which on turn depends upon epithelial-stromal interactions, degradation of extracellular matrix and reorganization of fibrillar components. Even though several aspects of the stromal and cellular remodeling have been elucidated and described, such as the epithelial-mesenchymal transition (EMT) and extracellular matrix degradation, all the underlying molecular mechanism are far to be elucidated in their complexity. In this review we focused on new actors such as microRNAs, G protein coupled receptor kinases (GRKs) and Calcium/calmodulin-dependent protein kinase (CaMKs) known to be involved in several important physiological processes like development, cell differentiation and cell signaling, and more recently linked to tumor progression and invasion.

关键词： Metastasis Angiogenesis miRNA GRKs CaMKs

Whole-Body 64-Slice Multidetector Computed Tomography (MDCT) Identifies High-Risk Myeloma

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International Journal of Clinical Medicine 2012年第7期3卷 644-649页

作者： Giuseppe Mele Grazia D’Agostino Giacomo Loseto maria Rosaria Coppi angela Melpignano Grazia Angone Giovanni Quarta Haematology Division and BMT Unit Antonio Perrino Hospital Hospital Brindisi Italy Radiology Division Antonio Perrino Hospital Hospital Brindisi Italy

Background: In Multiple Myeloma (MM) the individuation of bone lesions at baseline is mandatory because the detection of cortical damage reflects prognostic implications. Conventional Radiography (CR) shows osteolytic bone lesions only when the cortical bone damage is more than 30%. Whole-body 64-slice multidetector computed tomography (MDCT) has recently been employed for detecting early osteolytic disease. Patients and Methods: Twenty-height patients with Asymptomatic MM according to IMWG criteria underwent a 64 MDCT. Results: In our experience MDCT revealed osteolysis in 14/28 patients with normal skeletal survey and in 6 patients with normal Magnetic Resonance Imaging (MRI). Patients with radiological evidence of bone disease on MDCT were at high risk of progression with a median time to progression of 5 months (range 1 - 26 months) in comparison with patients without radiological evidence of bone disease who, conversely, showed a median time to progression of 20 months (range 8 - 40 months) (P = 0.0001). Conclusions: MDCT is able to identify MM patients with a high risk of progression, who might benefit from early therapy.

关键词： Asymptomatic Myeloma MDCT MRI Conventional Radiography

Impact of hormonal modulation at proestrus on ovarian responses and uterine gene expression of suckled anestrous beef cows

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Journal of Animal Science and Biotechnology 2018年第1期9卷 77-90页

作者： Manoel Francisco de Sá Filho angela maria Gonella-Diaza mariana Sponchiado Marcio Ferreira Mendanha Guilherme Pugliesi Roney dos Santos Ramos Sónia Cristina da Silva Andrade Gustavo Gasparin Luiz Lehmann Coutinho Marcelo Demarchi Goissis Fernando Silveira Mesquita Pietro Sampaio Baruselli Mario Binelli Departamento de Reproducao Animal FMVZ USP Sao Paulo SP Brazil Departamento de Genetica e Biologia Evolutiva IB-USP- Sao Paulo SP Brazil Laboratorio de Biotecnologia Animal ESALQ USP Av Padua Dias Piracicaba SP 11 Brazil Universidade Federal do Pampa Uruguaiana RS Brazil Universidade de Sao Paulo Faculdade de Medicina Veterinriae Zootecnia Departamento de Reprodcao Animal Avenida Duque de Caxias Norte 225 Pirassununga SP Zip Code 13635900 Brazil

Background： This study evaluated the impact of hormonal modulation at the onset of proestrus on ovarian response and uterine gene expression of beef ***： A total of 172 anestrous beef cows were assigned to one of four groups according to the treatment with estradiol cypionate（ECP） and/or equine chorionic gonadotropin（eCG） [CON（n = 43）, ECP（n = 43）, eCG（n = 44）and ECP ＋ eCG（n = 42）].Results： ECP-treated cows（ECP and ECP ＋ eCG groups） presented greater occurrence of estrus（44.6% vs. 65.4%; P = 0.01） and pregnancy per AI [47.1% vs. 33.3%; P = 0.07], but similar progesterone（P4） concentration at subsequent diestrus than cows not treated with ECP（CON and eCG groups）. Nonetheless, eCG-treated cows（eCG and ECP ＋ eCG groups） presented larger follicle at timed AI（12.6 ± 0.3 vs. 13.5 ± 0.3 mm; P = 0.03）, greater ovulation rate（96.5%vs. 82.6%; P = 0.008） and greater P4 concentration at d 6（3.9 ± 0.2 vs. 4.8 ± 0.2 ng/mL; P = 0.001） than cows not treated with eCG（CON and ECP groups）. Next, cows with a new corpus luteum 6 d after TAI were submitted to uterine biopsy procedure. Uterine fragments [CON（n = 6）, ECP（n = 6）] were analyzed by RNA-Seq and a total of 135 transcripts were differentially expressed between groups（73 genes up-regulated by ECP treatment）. Subsequently,uterine samples were analyzed by q PCR（genes associated with cell proliferation）. ECP treatment induced greater abundance of PTCH2（P = 0.07） and COL4 A1（P = 0.02）, whereas suppressed EGFR（P = 0.09） expression. Conversely, eCG treatment increased abundance of HB-EGF（P = 0.06）, ESR2（P = 0.09）, and ITGB3（P = 0.05）, whereas it reduced transcription of ESR1（P = 0.05）. Collectively, supplementation with ECP or eCG at the onset of proestrous of anestrous beef cows influenced ovarian responses, global and specific endometrial gene ***： Proestrus estradiol regulate the endometrial transcriptome, particularly stimulating proliferative activity in the endometrium.

关键词： Cattle eCG Endometrium Estradiol Transcriptome

Bifidobacteria as Potential Functional Starter Cultures: A Case Study by MSc Students in Food Science and Technology (University of Foggia, Southern Italy)

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Food and Nutrition Sciences 2012年第1期3卷 55-63页

作者： Antonio Bevilacqua maria Teresa Cagnazzo Cataldo Caldarola Emanuela Ciuffreda Anna Rita Dragano Stefania Franchino Rossana Lauriola angela Pacifico maria Rosaria Corbo Milena Sinigaglia 不详

This research paper was the results of activity of MSc students of Food Science and Technology, attending the class “Biotechnology of Functional Starter”. Five strains of bifidobacteria (Bifidobacterium animalis subsp. lactis;B. longum subsp. infantis;B. breve;B. animalis subsp. animalis;B. bifidum) were evaluated in order to assess their suitability as functional starter cultures, by studying the following technological and probiotic traits: growth at different temperatures, NaCl amounts and pH values;acidifying ability;metabolism (arginin deamination, esculin hydrolysis, acetoin production);survival at low pH and in presence of bile salts;hydrophobic properties;antibiotic resistance. After laboratory assays and strain selection through a multivariate analyses, it was highlighted that B. longum subsp. infantis and B. animalis subsp. lactis represent a good compromise as potential functional starter cultures, as B. animalis subp. lactis showed a high growth index at pH 5 and good values at 25?C and 30?C, as well as the minimal viability loss at pH 2.5. B. longum subsp. infantis DSMZ 20088 was the best microorganism for its growth index in presence of 6.5% of salt added and at 25?C and 30?C.

关键词： Bifidobacteria Functional Starter Probiotic Properties Technological Characterization

Mapping the Genetic Diversity of Castanea sativa: Exploiting Spatial Analysis for Biogeography and Conservation Studies

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Journal of Geographic Information System 2016年第2期8卷 248-259页

作者： Francesca Chiocchini Claudia Mattioni Paola Pollegioni Ilaria Lusini maria angela Martín Marcello Cherubini Marco Lauteri Fiorella Villani C.N.R. Institute of Agro-environmental and Forest Biology Terni Italy Departamento de Ingeniería del Medio Agronómico y Forestal Avda. Virgen del Puerto 2 Centro Universitario de Plasencia Universidad de Extremadura Caceres Spain

The current distribution of forest tree species is a result of natural or human mediated historical and contemporary processes. Knowledge of the spatial distribution of the diversity and divergence of populations is crucial for managing and conserving genetic resources in forest tree species. By combining tools from population genetics, landscape ecology and spatial statistics, landscape genetics thus represents a powerful method for evaluating the geographic patterns of genetic resources at the population level. In this study, we explore the possibility of combining genetic diversity data, spatial statistic tools and GIS technologies to map the genetic divergence and diversity of 31 Castanea sativa populations collected in Spain, Italy, Greece, and Turkey. The IDW technique was used to interpolate the diversity values and divergence indices as expected hetereozygosity (He), allelic richness (Rs), private allelic richness (PRs), and membership values (Q) of each population to different clusters. Genetic diversity maps and a synthetic map of the spatial genetic structure of European chestnut populations were produced. Spatial coincidences between landscape elements and statistically significant genetic discontinuities between populations were investigated. Evidence is provided of the significance of cartographic outputs produced in the study and on their usefulness in managing genetic resources.

关键词： Landscape Genetics Microsatellites Genetic Structure Spatial Interpolation Genetic Barriers