On the scalar curvature of constant mean curvature hypersurfaces in space forms

In this paper we study the behavior of the scalar curvature $S$ of a complete hypersurface immersed with constant mean curvature into a Riemannian space form of constant curvature, deriving a sharp estimate for the infimum of $S$. Our results will be an application of a weak Omori-Yau maximum principle due to Pigola, Rigoli and Setti \cite{PRS}.Comment: Final version (August 2009). To appear in Journal of Mathematical Analysis and Applications. Dedicated to Professor Marcos Dajczer on the occasion of his 60th birthda

Could an increase in education raise income inequality? : evidence for Latin America

This paper explores the direct effect of an education expansion on the level of earnings inequality by carrying out microsimulations for most Latin American countries. We find that the direct effect of the increase in years of education in the region in the 1990s and 2000s was unequalizing; this result is expected to hold for future expansions if increases in education are not highly progressive. Both facts are closely linked to the convexity of returns to education in the labor market. On average, the estimated impact of the education expansion remains unequalizing when allowing for changes in returns to schooling, although the effect becomes smaller.Fil: Battistón, Diego Ezequiel. Universidad Nacional de la Plata. Facultad de Ciencias Económicas. Departamento de Ciencias Económicas. Centro de Estudios Distributivos Laborales y Sociales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garcia Domench, Carolina. Universidad Nacional de la Plata. Facultad de Ciencias Económicas. Departamento de Ciencias Económicas. Centro de Estudios Distributivos Laborales y Sociales; ArgentinaFil: Gasparini, Leonardo Carlos. Universidad Nacional de la Plata. Facultad de Ciencias Económicas. Departamento de Ciencias Económicas. Centro de Estudios Distributivos Laborales y Sociales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Effect of Class Size on Teaching Middle School English Language Learners

Class size is an issue in American K-12 education that researchers have examined and debated for years. Documented research studies conducted on the impact of class size on student achievement have not come to concrete conclusions due to the minimal influence of federal class size reduction programs throughout the United States. Furthermore, despite the vast body of literature concerning the class size and its impact on student achievement, focusing primarily on students in the elementary grades, there is a distinct lack of scholarship focusing on the effect of class size on teaching English Language Learners (ELL) and attempt to fill this gap in the research literature. A qualitative research design was used to collect data from a sample from teachers currently employed in one Bay Area school district for this study. The results of the study suggested that class size did play a role in and affected the teaching of ELL students in large mainstream academic classrooms. In particular, this study indicated that certain elements of teaching, such as pacing and individualized student attention are affected

Impacto toxicológico de três terapêuticas farmacológicas em espermatozoides humanos

Therapeutic drugs can negatively affect male fertility by inducing toxic effects that impair sperm production and/or function. Some drugs are able to cross the blood-testis barrier (BTB) and act directly on germ cells, interfering with sperm function. With the world pandemic of COVID-19, several drugs were repurposed as treatment options. As a result, these drugs started to be extensively administered worldwide. The urge for full knowledge on drugs’ safety became even more evident, to avoid undesirable side effects. Therefore, the aim of this in vitro study was to evaluate the toxicological effects of three therapeutic drugs used in COVID-19, in human sperm cells. Hydroxychloroquine (HCQ; antimalarial), dexamethasone (DEX; glucocorticoid) and remdesivir (RDV; antiviral) were the drugs studied. DEX and RDV are also recommend in co-administration for some COVID-19 patients, thus, these two drugs were evaluated for individual combined effects. Sperm vitality and motility, sperm oxidative stress and DNA damages were assessed in sperm cells exposed to usual therapeutic regimen of each drug and compared to a control group. HCQ was the only drug to induce significant effects in sperm vitality and motility. All drugs induced sperm DNA fragmentation, without alter the oxidative stress levels. Therefore, this study suggests HCQ is the most toxic drug for sperm cells, and that sperm DNA fragmentation is induced by different mechanism rather than exclusively due to oxidative stress. Moreover, results outlined the importance to include sperm DNA fragmentation evaluation in routine sperm analysis at fertility clinics. DEX and RDV seem to have addictive effects when administered simultaneously, however, further investigation is required to confirm these effects.A fertilidade masculina pode ser negativamente afetada por diversos fármacos, que induzem efeitos tóxicos no sistema reprodutor masculino, resultando em profundas alterações na formação e/ou função dos espermatozoides. Alguns fármacos são capazes de atravessar a barreira hemato-testicular e atuar diretamente nas células germinativas podendo vir a interferir com a capacidade de fertilização dos espermatozoides. A pandemia COVID-19 obrigou à mobilização de diversos recursos farmacológicos. Inúmeros fármacos foram repropostos como tratamento para a COVID-19, passando a ser amplamente administrados em todo o mundo, tornando-se ainda mais urgente o total conhecimento da segurança dos fármacos em questão. Assim sendo, foi desenhado este estudo in vitro, para avaliar os efeitos de três fármacos utilizados como terapia para pacientes COVID-19 nos espermatozoides humanos. Hidroxicloroquina (HCQ; antimalárico), dexametasona (DEX, glucocorticoide) e remdesivir (RDV; antiviral) foram os fármacos estudados, sendo que a DEX e o RDV foram testados individualmente e em combinação. Os espermatozoides foram expostos às concentrações terapêuticas dos fármacos e os seguintes parâmetros foram avaliados: vitalidade, motilidade, stress oxidativo e danos no DNA. De acordo com os resultados, apenas a HCQ diminuiu significativamente a vitalidade e motilidade dos espermatozoides. Todos os fármacos induziram fragmentação no DNA espérmico, ainda que sem alterar os níveis de stress oxidativo. Assim, concluiu-se que a HCQ é o fármaco com maior potencial tóxico para os espermatozoides, induzindo danos ao nível macro e microscópico, e que a fragmentação do DNA é induzida por mecanismos que não implicam unicamente produção de espécies reativas de oxigénio. Mais ainda, este estudo tornou evidente a necessidade de incluir uma análise ao DNA espérmico nos espermogramas realizados em clinicas de fertilidade. DEX e RDV parecem ter um efeito aditivo quando administrados em conjunto, no entanto é necessário um estudo mais aprofundado para confirmar os seus efeitos em concomitância.Mestrado em Biomedicina Molecula

Do the results of canadian hockey have any influence in sports-related company stocks?

Mestrado em FinançasO hóquei no gelo é considerado o desporto rei do Canadá, neste contexto, o hóquei faz mexer muito dinheiro na economia do país. Este estudo empírico tem como objetivo avaliar o impacto dos resultados desportivos do hóquei canadiano no valor de mercado das empresas relacionados com o desporto estudado. Isto foi conseguido usando a metodologia de estudo de eventos em 4 empresas relacionadas com desporto, cotadas na Bolsa Canadiana, e quatro equipas canadianas de hóquei no gelo, que jogam na Liga Nacional de Hóquei no Gelo, entre 2005 e 2015. Posteriormente foram testados seis diferentes testes de hipóteses do impacto que os resultados do hóquei têm nas empresas: vitória e derrota; muitos golos e poucos golos; e adversário "fácil" e adversário "difícil". A metodologia usada nesta dissertação é a de estudos de eventos, onde são calculados os retornos anormais (AR) e os retornos anormais médios a fim de se concluir se existe evidência de que os resultados desportivos levam a retornos anormais. Os resultados obtidos mostram que existem AR como resultado dos resultados desportivos do hóquei no gelo. O valor de mercado das empresas é positivamente afetado por uma vitória e negativamente por uma derrota. Adicionalmente, uma vitória por uma diferença de golos grande tem um efeito negativo, enquanto uma vitória por uma diferença de golos pequena tem um efeito positivo. Por fim, uma vitória contra um oponente "difícil" ou "fácil" tem um impacto negativo ou positivo, respetivamente, nas ações das empresas.Ice hockey is considered the main sport in Canada, hence moving a lot of money in the country's economy, more specifically in sport related companies. This empirical study's objective is to evaluate the impact that Canadian ice hockey outcomes has on the abnormal returns of sport-related company. This was accomplished by using the event study methodology on 4 sport-related companies, quoted on the Canadian Stock Exchange, and four Canadian hockey team, playing in the National Hockey League, between 2005 and 2015. The NHL is a professional ice hockey league composed by American and Canadian teams. Subsequently 3 different hypotheses were tested on the impact of the hockey results: Win and Loss; Many Goals and Less Goals; and "easy" opponent and "hard" opponent. The methodology used by this dissertation is the event study methodology, where abnormal returns and average abnormal returns are calculated in order to conclude if there is evidence that sports results lead to abnormal returns. Findings indicate that there are abnormal returns as a result of sporting results. The market values of the companies are positively affected by a victory and negatively by a defeat. Additionally, a win by a large amount of goals difference negatively impacts the stock prices, while a win by a less amount of goals affects negatively the company value. Finally, a win against a "hard" or "easy" opponent affects the stock price of the sport-related companies negatively and positively, respectively. A loss depends on the company that is being analyzed

THE CIRCULAR ECONOMY IN THE FASHION INDUSTRY: IMPLICATIONS AND CHALLENGES FOR ITALIAN SMEs

Current business practices and consumption patterns within the fashion industry have driven this sector towards the first positions in the ranking of most polluting economic systems. The situation has reached a point where mainstream sustainable practices cannot cope with the problem, leading the path to a new approach, the Circular Economy. This novel term aims to change the conception from recycling to reusing, closing the loop of economic systems transforming waste into inputs in a continuous circling of materials. The present document studies the implications of the Circular Economy from the perspective of the most representative companies in the fashion industry, small and medium enterprises. The objective is to answer the questions regarding how these companies integrate the Circular Economy in their supply chain management practices, and which challenges they encounter in the process. Thus, it comprises an explorative research aiming to provide the bases for the discovery of new knowledge on the matter. Data collection is based on semi-structured interviews with seven small and medium enterprises in Italy. Information is then analysed and contrasted with existing literature on the topic leading to reliable and valid answers to the questions. Findings show how there is a difference between the relevance of Circular Economy aspects depending on the nature of the closing loop. In other words, the integration of the approach is directly related with the nature of the companies’ resources, being these new or reused. At the same time, it also affects the challenges, originated within the upstream component of the chain for those organizations regenerating resources from other industries; whereas being the downstream component the main source of difficulties for those small and medium enterprises using new eco and bio resources.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

RECOGNIZING CHILD ABUSE IN THE CLASSROOM

The purpose of this study was to identify educators’ perceptions of Mandated Reporting Training. This study used a quantitative design with 88 participants from Southern California. Child abuse can impact a child’s life severely and may even cause death in extreme situations. Child Protection Services receives millions of child abuse allegations every year. Abuse continues to be underreported despite state regulations that require teachers to complete the Mandated Reporter Training. Professionals in the educational field believe this training is insufficient as it is only taken once a year and does not provide enough information to report and identify abuse. This research study evaluated teacher’s perspectives about the effectiveness of the Mandated Reporter Training to assess if it was sufficient in helping teachers identify and report abuse. The research question was “Is there is a relationship between mandated reporter training, experience, and preparedness to report child abuse in teachers?” The research was conducted through an online questionnaire that was created using Qualtrics. Participants were recruited using social media platforms such as LinkedIn, Facebook, and Instagram. The study found that most educators received training and were able to identify signs of abuse. Future research should focus on using qualitative interviews with open-ended questions to obtain more knowledge. The study also recommends a collaboration on trainings between educators and social workers in child welfare

30th Annual Willem C. Vis International Commercial Arbitration Moot

31st March – 6th April 2023 in Vienna, Austri

Eigenvalue estimates for submanifolds of warped product spaces

We give lower bounds for the fundamental tone of open sets in minimal submanifolds immersed into warped product spaces of type $N^n \times_f Q^q$, where $f \in C^\infty(N)$. We also study the essential spectrum of these minimal submanifolds.Comment: 17 page