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Raman spectroscopy can detect conformational changes in collagen structures and these findings are reviewed in this article. More specifically, some progressive diseases are mainly caused by alterations of collagen molecules but what is occurring at the biochemical level of this complex molecule usually remains unclear. While it may be true that a number of analytical techniques can analyze collagen, most of them have a series of limitations that limit their applicability to a wide range of samples. To understand in more detail the progression of a disease due to changes in the collagen structure, a technique that can detect subtle alterations at the biochemical level is needed. Raman spectroscopy is a label-free and noninvasive technique that can easily pick up on any conformational changes reflected primarily at the lipids, amides and proline and hydroxyproline regions. This review is the first compilation of studies of conformational changes in collagen molecules, providing help to understand changes in collagen biochemistry that can be of relevance to the human wound healing, ageing and pathologies.

Injectable, self-setting calcium phosphate cements (CPCs) are synthetic bone substitutes considered favorable for the repair and regeneration of bone due to their osteocompatibility and unique handling properties. However, their clinical applicability can be compromised due to insufficient cohesion upon injection into the body coupled with poor degradation rates that restricts new bone formation. Consequently, carboxymethyl cellulose (CMC) was incorporated into CPC formulations to improve their cohesion and injectability while poly ( D,L -lactic-co-glycolic acid) (PLGA) porogens were added to introduce macroporosity and improve their biodegradation rate. Like most biomaterials, CPCs are gamma irradiated before clinical use to ensure sufficient sterilization. However, it is well known that gamma irradiation also reduces the molecular weight of CMC and PLGA via chain scission, which affects their material properties. Therefore, the aim of this study is to measure the effect that gamma irradiation has on the molecular weight of CMC at varying doses of 15, 40, or 80 kGy and investigate how this affects the handling (i.e., injectability, cohesion, washout, and setting times) and in vitro degradation behavior of CPC formulations. Results reveal that the molecular weight of CMC decreases with increasing gamma irradiation dose, thereby reducing the viscosifying capabilities of CMC, which causes CPCs to deteriorate more readily. Further, the addition of CMC seems to inhibit the degree of phase transformation during cement setting while the subsequent reduction in molecular weight of PLGA after gamma irradiation improves the in vitro degradation rate of CPCs due to the faster degradation rate of low molecular weight PLGA. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2216-2228, 2019.

Chicken and eggs are an important source of protein for humans worldwide. Production of these foods has been intensified in recent years and around 150 million tonnes of chicken meat is expected to be produced by 2020 (OECD / FAO, 2018). However, one of the biggest problems linked to poultry production processes are the infectious diseases caused by pathogenic microorganisms. Among the most relevant are found microorganisms such as Salmonella ssp, Campylobacter spp, and Escherichia coli. Therefore, it is important to understand the mechanisms involved in the colonization of pathogenic microorganisms that can affect poultry and their interactions with the gastrointestinal microbiota, which are key in improving nutrient absorption and strengthening the immune system, which it influences the growth, welfare and health of the chicken. However, there is little information related to the gastrointestinal microbiota of chicken. Until recently, the characterization was limited to microorganisms that could be recovered through culture traditional. Therefore, in the last time, it has been intensified use of molecular techniques, among those is remarked metagenomics, which offers an alternative for a better understanding of bacterial interactions, the identification of antibiotic resistance genes, identification of mobile genetic elements, and the design of strategies for more effective interventions with the aim of breaking the chain of transmission of pathogenic microorganisms during the poultry production cycle. In this review, the main metagenomics approaches are describe aimed to study microbiomes from poultry, sequencing techniques and bioinformatics tools used for its characterization., El pollo y el huevo son una fuente importante de proteína para el ser humano a nivel mundial. La producción de estos alimentos se ha intensificado durante los últimos años y se prevé que se produzca alrededor de 1 50 millones de toneladas de carne de pollo en 2020 (OCDE / FAO, 2018). Sin embargo, uno de los mayores problemas ligados a los procesos de producción avícola lo constituyen las enfermedades infecciosas ocasionadas por microorganismos patógenos. Entre los más relevantes se encuentran microorganismos como Salmonella ssp, Campylobacter spp, y Escherichia coli. Por lo tanto, es importante comprender los mecanismos implicados en la colonización de microorganismos patógenos que afectan a las aves de corral y sus interacciones con la microbiota gastrointestinal las cuales son clave en la mejora de la absorción de nutrientes y el fortalecimiento del sistema inmune, que influye en el crecimiento, el bienestar y la salud de las aves de corral. Sin embargo, hay poca información relacionada con la microbiota gastrointestinal de pollos parrilleros y gallinas productoras de huevo. Hasta hace poco, la caracterización se limitaba a los microorganismos que podían recuperarse a través de cultivos tradicionales. Por lo anterior, en el último tiempo se ha intensificado el uso de técnicas moleculares, entre las que se destaca la metagenómica, la cual ofrece una alternativa para una mejor comprensión de las interacciones bacterianas, la identificación de genes de resistencia a los antibióticos, identificación de elementos genéticos móviles, y el diseño de estrategias para intervenciones más efectivas con el objetivo de romper la cadena de transmisión de microorganismos patógenos durante el ciclo de producción avícola. En esta revisión, se describen los principales enfoques metagenómicos para el estudio de microbiomas de aves de corral, las técnicas de secuenciación y herramientas bioinformáticas usadas para su caracterización.

Recognition is a normative concept. By recognizing someone as having certain characteristics or capabilities, we recognize their normative status and we are taking responsibility for treating them in a certain way. Non-recognition, in this case, can mean deprivation of rights and marginalization; in a democracy may preclude individuals or groups from enjoying the democratic egalitarian ideal, for example. Over the past three decades, reflection on this category has deepened and taken on greater importance in the debate between liberalism and communitarianism parallel to the demands, sometimes for the achievements, of groups and minorities (LGBTQIA, people with special needs, feminist, indigenous, ethnic, etc.) who feel unrecognized and engage in political movements through struggles for recognition. We will return here to the development of Axel Honneth's concept of "ethical life" in 'Struggle for Recognition' (1992), a fundamental work for reflection on the theme. The author places his theory in the middle between Kantian morality and communitarian ethics: his conception is formal for he understands that universal norms are conditions of some possibilities, but they are substantive for they are guided by the end of human self-realization.

Recognition is a normative concept. By recognizing someone as having certain characteristics or capabilities, we recognize their normative status and we are taking responsibility for treating them in a certain way. Non-recognition, in this case, can mean deprivation of rights and marginalization; in a democracy may preclude individuals or groups from enjoying the democratic egalitarian ideal, for example. Over the past three decades, reflection on this category has deepened and taken on greater importance in the debate between liberalism and communitarianism parallel to the demands, sometimes for the achievements, of groups and minorities (LGBTQIA, people with special needs, feminist, indigenous, ethnic, etc.) who feel unrecognized and engage in political movements through struggles for recognition. We will return here to the development of Axel Honneth's concept of "ethical life" in Struggle for Recognition (1992), a fundamental work for reflection on the theme. The author places his theory in the middle between Kantian morality and communitarian ethics: his conception is formal for he understands that universal norms are conditions of some possibilities, but they are substantive for they are guided by the end of human self-realization., O reconhecimento é um conceito normativo. Ao reconhecermos alguém como portador de determinadas características ou capacidades, reconhecemos seu status normativo e estamos assumindo responsabilidade por tratar este alguém de determinada forma. O não reconhecimento, neste caso, pode significar privação de direitos e marginalização; em uma democracia pode impossibilitar indivíduos ou grupos de desfrutar o ideal igualitário democrático, por exemplo. Nas últimas três décadas, a reflexão sobre esta categoria se aprofundou e assumiu maior importância no debate entre liberalismo e comunitarismo em paralelo às demandas, por vezes pelas conquistas, de grupos e minorias (LGBTQIA, portadores de necessidades especiais, feministas, indígenas, étnicos, etc.) que se sentem não reconhecidos e se engajam em movimentos políticos através de lutas por reconhecimento. Retomaremos, aqui, o desenvolvimento do conceito de “eticidade” empreendido por Axel Honneth em Luta por reconhecimento (1992), obra fundamental para a reflexão sobre o tema. O autor situa sua teoria no meio termo entre a moral kantiana e as éticas comunitaristas: sua concepção é formal por entender que normas universais são condições de algumas possibilidades, mas é substantiva por se orientar pelo fim da autorrealização humana.

O reconhecimento é um conceito normativo. Ao reconhecermos alguém como portador de determinadas características ou capacidades, reconhecemos seu status normativo e estamos assumindo responsabilidade por tratar este alguém de determinada forma. O não reconhecimento, neste caso, pode significar privação de direitos e marginalização; em uma democracia pode impossibilitar indivíduos ou grupos de desfrutar o ideal igualitário democrático, por exemplo. Nas últimas três décadas, a reflexão sobre esta categoria se aprofundou e assumiu maior importância no debate entre liberalismo e comunitarismo em paralelo às demandas, por vezes pelas conquistas, de grupos e minorias (LGBTQIA, portadores de necessidades especiais, feministas, indígenas, étnicos, etc.) que se sentem não reconhecidos e se engajam em movimentos políticos através de lutas por reconhecimento. Retomaremos, aqui, o desenvolvimento do conceito de “eticidade” empreendido por Axel Honneth em Luta por reconhecimento (1992), obra fundamental para a reflexão sobre o tema. O autor situa sua teoria no meio termo entre a moral kantiana e as éticas comunitaristas: sua concepção é formal por entender que normas universais são condições de algumas possibilidades, mas é substantiva por se orientar pelo fim da autorrealização humana., Recognition is a normative concept. By recognizing someone as having certain characteristics or capabilities, we recognize their normative status and we are taking responsibility for treating them in a certain way. Non-recognition, in this case, can mean deprivation of rights and marginalization; in a democracy may preclude individuals or groups from enjoying the democratic egalitarian ideal, for example. Over the past three decades, reflection on this category has deepened and taken on greater importance in the debate between liberalism and communitarianism parallel to the demands, sometimes for the achievements, of groups and minorities (LGBTQIA, people with special needs, feminist, indigenous, ethnic, etc.) who feel unrecognized and engage in political movements through struggles for recognition. We will return here to the development of Axel Honneth's concept of "ethical life" in Struggle for Recognition (1992), a fundamental work for reflection on the theme. The author places his theory in the middle between Kantian morality and communitarian ethics: his conception is formal for he understands that universal norms are conditions of some possibilities, but they are substantive for they are guided by the end of human self-realization.

This study uses data from an urban school district to examine the relation between students' motivational beliefs about mathematics and high- versus low-stakes math test performance. We use ordinary least squares and quantile regression analyses and find that the association between students' motivation and test performance differs based on the stakes of the exam. Students' math self-efficacy and performance avoidance goal orientation were the strongest predictors for both exams; however, students' math self-efficacy was more strongly related to achievement on the low-stakes exam. Students' motivational beliefs had a stronger association at the low-stakes exam proficiency cutoff than they did at the high-stakes passing cutoff. Lastly, the negative association between performance avoidance goals and high-stakes performance showed a decreasing trend across the achievement distribution, suggesting that performance avoidance goals are more detrimental for lower achieving students. These findings help parse out the ways motivation influences achievement under different stakes.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture; and, Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1998., Includes bibliographical references (leaves 95-98)., Research was conducted in Mexico in order to determine the size, future growth and current status of the Mexican residential mortgage market, and to assess the potential for securitization. Securitization offers good prospects of liquifying the mortgage loans enabling these funds to be reinvested into the housing market. In the long run, securitization can also attract other sources of capital, both foreign and domestic, to the housing market. The key elements of structuring these securities lie in the underwriting standards and loan origination systems that are effectuated. Poor origination and collecting practices will hinder the success of securitization. The development of an efficient primary market would facilitate the sale of loans in the secondary market, increasing capital flow efficiencies. Interviews with private and Federal authorities confirmed that securitization is being actively pursued and encouraged by the Mexican government. Some of the important questions to be answered are; how quickly can the primary market be developed, what impact will the new foreclosure laws have on recovery rates, what demand will the domestic markets have for these securities, and how quickly can foreign investment be attracted. But at this moment, the most important question to be answered is to what degree the government should be involved in developing the secondary market. It was found that FOVI will be further developed to act as an originating agency since it is currently one of the only sources of funding for residential mortgages in Mexico. The immediate future for securitizing mortgages rests on the precedent set by these new FOVI loans., by Marcela Fernandez Martinez and Anthony James Simboli., S.M.