1,760 research outputs found
The plasticizer butyl benzyl phthalate induces genomic changes in rat mammary gland after neonatal/prepubertal exposure
Background: Phthalate esters like n-butyl benzyl phthalate (BBP) are widely used plasticizers. BBP has shown endocrine-disrupting properties, thus having a potential effect on hormone-sensitive tissues. The aim of this study is to determine the effect of neonatal/prepubertal exposure (post-natal days 2-20) to BBP on maturation parameters and on the morphology, proliferative index and genomic signature of the rat mammary gland at different ages of development (21, 35, 50 and 100 days). Results: Here we show that exposure to BBP increased the uterine weight/body weight ratio at 21 days and decreased the body weight at time of vaginal opening. BBP did not induce significant changes on the morphology of the mammary gland, but increased proliferative index in terminal end buds at 35 days and in lobules 1 at several ages. Moreover, BBP had an effect on the genomic profile of the mammary gland mainly at the end of the exposure (21 days), becoming less prominent thereafter. By this age a significant number of genes related to proliferation and differentiation, communication and signal transduction were up-regulated in the glands of the exposed animals. Conclusion: These results suggest that BBP has an effect in the gene expression profile of the mammary gland
DEMOCRACIAS CON RACISMO, CONSECUENCIAS PARA LA CIUDADANÍA
In this work, the situation of “racist democracies” is differentiated from “democracies with racism” (the Mexican case). In Mexico, the conjunction of practices of collective and institutionalized discrimination by regions and social segments, with a regime of political democracy, is analyzed. The hypothesis that is maintained is that the assimilation of cultures in Mexico follows racist patterns and constitutes a form of denial of civilizational diversity (with diverse cultures, ethnicities, languages and religions). Evidence is offered of assimilation racism and its impact on the nation's weak constitution. The impact of racist dimensions of Mexican democracy on the constitution of dual rights giving rise to sub-citizenships is also analyzed.En este trabajo se diferencia la situación de “democracias racistas” respecto de “democracias con racismo” (el caso mexicano). Se analiza en México la conjunción de prácticas de discriminación colectiva e institucionalizadas por regiones y segmentos sociales, con un régimen de democracia política. La hipótesis que se sostiene es que la asimilación de culturas en México sigue patrones racistas y constituye una forma de negación de la diversidad civilizatoria (con culturas, etnias, lenguas y religiones diversas). Se ofrecen evidencias del racismo por asimilación y su impacto sobre la débil constitución de la nación. También se analiza el impacto de dimensiones racistas de la democracia mexicana sobre la constitución de la dualidad de derechos dando lugar a subciudadanías
Re-entrant phase behaviour of network fluids: A patchy particle model with temperature-dependent valence
We study a model consisting of particles with dissimilar bonding sites ("patches"), which exhibits self-assembly into chains connected by Y-junctions, and investigate its phase behaviour by both simulations and theory. We show that, as the energy cost epsilon(j) of forming Y-junctions increases, the extent of the liquid-vapour coexistence region at lower temperatures and densities is reduced. The phase diagram thus acquires a characteristic "pinched" shape in which the liquid branch density decreases as the temperature is lowered. To our knowledge, this is the first model in which the predicted topological phase transition between a fluid composed of short chains and a fluid rich in Y-junctions is actually observed. Above a certain threshold for epsilon(j), condensation ceases to exist because the entropy gain of forming Y-junctions can no longer offset their energy cost. We also show that the properties of these phase diagrams can be understood in terms of a temperature-dependent effective valence of the patchy particles. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3605703
DIAMOND OF THE DESERT: THE CASE OF QATAR’S 2022 FIFA WORLD CUP
For the first time in the Arab world, the FIFA World Cup in Qatar 2022 was one of the
main drivers for promoting important infrastructural changes in the country, as well as
for transforming the image of Qatar in order to make the destination more attractive to
foreign tourists. However, despite the great wealth from its Oil & Gas reserves, several
social challenges that historically affect the country began to emerge due to greater
coverage of the international media, threatening the expectations of positive legacies left
on the country\u27s image from the event. Given this context, the case puts the reader in the
role of Ahmed Al-Nasr, then Chairman of the Qatar Supreme Committee for Delivery
and Legacy, as he faces different pressures made by major international brands
sponsoring the event who now see their image threatened by successive controversies
that the country has been involved in and they are threatening to withdraw their support
and investments. The case is indicated for undergraduate and graduate students of
courses in the area of Tourism, Sport Management, and Business interested in discussing
topics and concepts related to environmental, social, and governance (ESG)
responsibility, management of mega events, international marketing, and country
destination image
PERCEPTIONS BETWEEN INDUSTRY-UNIVERSITY CONNECTIONS
ABSTRACT: One of the best ways to ensure the competitiveness of a company is through innovation, which can be derived from studies developed within universities. It is still incipient the use by the companies of the knowledge available in the universities to launch innovative products in the market. Those responsible for the planning and development of new companies should be aware of the new technological processes in the area in which they work, planning actions in the field of scientific and technological research, to generate knowledge and technologies that can be incorporated into the production system. They must know the mechanisms of technology transfer, as well as those that are directly linked to the diffusion of knowledge. In this context, university research plays an important role in the knowledge and development of new technologies applied to companies. Cooperation between companies and universities depends on the relationship between those involved and the resources that are allocated. These relationships involve mechanisms such as research support, cooperative research, knowledge transfer, and technology transfer. Thus, the connections between companies and universities follow a model of partnership existing between organizations of different nature, which may have different purposes, but collaborate unilaterally towards the same objectives. This article aimed to build and validate a structural model that demonstrates how and why Enterprise-University Connections occur. The population was formed by Brazilian researchers, who have patent registration. Through exploratory and confirmatory factor analysis, a valid measurement model was found at a significance level of 5%, formed by the following constructs: Types of Cooperation; Motivations of the Cooperation Process; Barriers to the Cooperation Process; Facilitators of the Process of Cooperation and Satisfaction of the Cooperation Process.Keywords: Technology Transfer; Industry-University Connections; Motivations; Barriers; Facilitators and Satisfaction. RESUMO: A inovação vinda dos estudos acadêmicos é vista como a melhor forma para garantir a continuidade de uma empresa. Mas, de modo geral, as empresas não se utilizam do conhecimento disponível nas universidades para colocar produtos inovadores no mercado. O gestor de empresa deve estar atento aos novos processos tecnológicos na área em que atua, deve planejar ações no campo da pesquisa científica e tecnológica, como forma de gerar conhecimentos e tecnologias que possam ser incorporadas ao sistema produtivo. Deve conhecer os mecanismos de transferência de tecnologia e os que afetam a difusão do conhecimento. Assim, as pesquisas realizadas em universidades vêm desempenhando um papel importante no âmbito do conhecimento e do desenvolvimento de novas tecnologias aplicadas à indústria. As relações de cooperação entre empresas e universidades dependem da relação entre os envolvidos, dos recursos comprometidos, e essas relações envolvem mecanismos, tais como suporte à pesquisa, pesquisa cooperativa, transferência de conhecimento e transferência de tecnologia. Essas conexões, entre empresas e universidades, seguem um modelo de parceria existente entre organizações de natureza distintas, que podem ter finalidades diferentes, mas colaboram unilateralmente para os mesmos objetivos. O objetivo principal deste artigo foi construir e validar um modelo para analisar como e porque ocorrem as Conexões Empresa-Universidade. A população foi formada por pesquisadores brasileiros, que possuem registro de patentes. Através da análise fatorial exploratória e confirmatória, foi gerado um modelo de mensuração válido a um nível de significância de 5%, formado pelos seguintes construtos: Tipos de Cooperação; Motivações do Processo de Cooperação; Barreiras do Processo de Cooperação; Facilitadores do Processo de Cooperação e Satisfação do Processo de Cooperação.Palavras-chaves: Transferência de Tecnologia; Conexões Empresa-Universidade; Motivações; Barreiras; Facilitadores e Satisfação.
On the stability and deformability of top stars
Topological stars, or top stars for brevity, are smooth horizonless static
solutions of Einstein-Maxwell theory in 5-d that reduce to spherically
symmetric solutions of Einstein-Maxwell-Dilaton theory in 4-d. We study linear
scalar perturbations of top stars and argue for their stability and
deformability. We tackle the problem with different techniques including WKB
approximation, numerical analysis, Breit-Wigner resonance method and quantum
Seiberg-Witten curves. We identify three classes of quasi-normal modes
corresponding to prompt-ring down modes, long-lived meta-stable modes and what
we dub `blind' modes. All mode frequencies we find have negative imaginary
parts, thus suggesting linear stability of top stars. Moreover we determine the
tidal Love and dissipation numbers encoding the response to tidal deformations
and, similarly to black holes, we find zero value in the static limit but,
contrary to black holes, we find non-trivial dynamical Love numbers and
vanishing dissipative effects at linear order. For the sake of illustration in
a simpler context, we also consider a toy model with a piece-wise constant
potential and a centrifugal barrier that captures most of the above features in
a qualitative fashion
Genetic determinants and absence of breast cancer in Xavante Indians in Sangradouro Reserve, Brazil
Genetic compositions of distinct human populations are different. How genomic variants influence many common and rare genetic diseases is always of great medical and anthropological interest, and understanding of genetic architectures of population groups in relation to diseases can advance our knowledge of medicine. Here, we have studied the genomic architecture of a group of Xavante Indians, an indigenous population in Brazil, and compared them with normal populations from the 1000 Genomes Projects. Principal component analysis (PCA) indicates that the Xavante Indians are genetically distinctive when compared to other ethnic groups. No incidence of breast cancer cases has ever been reported in the population, and polygenic risk analysis indicates extremely low breast cancer risk in this population when compared with germline TCGA (The Cancer Genome Atlas) breast cancer normal control samples. Low germinal mutation burden among this population is also observed. Our findings will help to deepen the understanding of breast cancer and might also provide new approaches to study the disease.publishersversionpublishe
Catalytic transformation of biomass-derived 5-hydroxymethylfurfural over supported bimetallic iridium-based catalysts
5-Hydroxymethylfurfural (HMF) is a biobased platform chemical that can be valorized into a spectrum of valuable products. In this report, supported Ir, Ir–Co, Ir–Ni, and Ir–Ru catalysts were investigated for this purpose. Only hydrogenation of HMF to 2,5-bis-(hydroxymethyl)furan (BHMF) occurred over all catalysts. The effect of the second metal (Co, Ni, and Ru) on Ir/SiO2 was reflected by the kinetic constants being in the order Ir–Ni/SiO2 > Ir–Co/SiO2 > Ir–Ru/SiO2. The oxophilic nature of the secondary metal improved the catalytic performance of the bimetallic catalysts compared to the monometallic iridium catalyst (Ir/SiO2). Addition of HCOOH and H2SO4 as cocatalysts is a strategy to reach one-pot conversion of HMF to 2,5-di-methylfuran (DMF). Over-hydrogenolysis products such as 2,5-dimethyltetrahydrofuran were formed when only H2SO4 was added, giving higher activity compared to addition of HCOOH. Simultaneous presence of acids gave the highest HMF conversion, promoting esterification to 5-formyloxymethyl furfural and allowing the one-pot transformation of HMF to DMF. Thermodynamic analysis of HMF transformations revealed that both hydrogenation and dehydration steps are feasible.Peer ReviewedPostprint (author's final draft
Demographic, Clinical, And Laboratory Parameters Of Cystic Fibrosis During The Last Two Decades: A Comparative Analysis.
In recent years, patients with cystic fibrosis (CF) have tended to experience a longer life expectancy and higher quality of life. In this context, the aim of the present study was to evaluate and compare the demographic, clinical, and laboratory markers of patients with CF during the last two decades at a CF referral center. A retrospective study of the demographic, clinical, and laboratory markers for CF treatment at a CF referral center was performed during two decades: 2000 (DI, 1990-2000, n = 104 patients) and 2010 (DII, 2000-2010, n = 181 patients). The following variables were less common in DI than in DII: (i) pancreatic insufficiency, (ii) meconium ileus, (iii) diabetes mellitus, (iv) Burkholderia cepacia colonization, (v) moderate and severe Shwachman-Kulczycki score (SKS), (vi) F508del mutation screening, (vii) patients without an identified CFTR mutation (class IV, V, or VI mutation), (viii) patients above the 10th percentile for weight and height, (ix) restrictive lung disease, and (x) older patients (p < 0.01). The following variables were more common in DI than in DII: (i) excellent and good SKS, (ii) F508del heterozygous status, (iii) colonization by mucoid and nonmucoid Pseudomonas aeruginosa, (iv) obstructive lung disease, and (v) minimal time for CF diagnosis (p < 0.01). Clinical outcomes differed between the two decades. Demographic, clinical, and laboratory markers in patients with CF are useful tools and should be encouraged in CF referral centers to determine the results of CF management and treatment, enabling a better understanding of this disease and its clinical evolution. Early diagnosis and management of CF will improve patients' quality of life and life expectancy until personalized drug therapy is possible for all patients with CF.15
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