Case-based reasoning and system design: An integrated approach based on ontology and preference modeling

This paper addresses the fulfillment of requirements related to case-based reasoning (CBR) processes for system design. Considering that CBR processes are well suited for problem solving, the proposed method concerns the definition of an integrated CBR process in line with system engineering principles. After the definition of the requirements that the approach has to fulfill, an ontology is defined to capitalize knowledge about the design within concepts. Based on the ontology, models are provided for requirements and solutions representation. Next, a recursive CBR process, suitable for system design, is provided. Uncertainty and designer preferences as well as ontological guidelines are considered during the requirements definition, the compatible cases retrieval, and the solution definition steps. This approach is designed to give flexibility within the CBR process as well as to provide guidelines to the designer. Such questions as the following are conjointly treated: how to guide the designer to be sure that the requirements are correctly defined and suitable for the retrieval step, how to retrieve cases when there are no available similarity measures, and how to enlarge the research scope during the retrieval step to obtain a sufficient panel of solutions. Finally, an example of system engineering in the aeronautic domain illustrates the proposed method. A testbed has been developed and carried out to evaluate the performance of the retrieval algorithm and a software prototype has been developed in order to test the approach. The outcome of this work is a recursive CBR process suitable to engineering design and compatible with standards. Requirements are modeled by means of flexible constraints, where the designer preferences are used to express the flexibility. Similar solutions can be retrieved even if similarity measures between features are not available. Simultaneously, ontological guidelines are used to guide the process and to aid the designer to express her/his preferences

Propuesta de mejora en gestión de la calidad en el uso de energía renovable del proyecto de electrificación rural, en la comunidad de Chilete - Contumaza, Región de Cajamarca

[Originalmente sin resumen. Texto extraído del Objetivo General:] Proponer la optimización de la gestión de la calidad en el uso de energía renovable del proyecto de electrificación rural, en la comunidad de Chilete – Contumazá, región de Cajamarca- 2019.Trabajo de investigaciónCampus Lima Centr

Solvent-free formation of cyclodextrin-based pseudopolyrotaxanes of polyethylene glycol: kinetic and structural aspects

Pseudopolyrotaxanes (PPRs) are supramolecular structures consisting of macrocycles able to thread on a linear polymer chain in a reversible, non-covalent way, often referred to in the literature as "molecular necklaces". While the synthesis and reaction mechanisms of these structures in solution have been widely described, their solvent-free production has received little attention, despite the advantages that this route may offer. We propose in this work a kinetic mechanism that describes the PPR formation in the solid phase as a process occurring in two consecutive stages. This mechanism has been used to investigate the spontaneous formation of a PPR that occurs when grinding alpha-Cyclodextrin (alpha-CD) with polyethylene glycol (PEG). In the threading stage, the inclusion of the polymer and subsequent release of the water molecules lodged in the cavity of the macrocycle cause vibrational changes that are reflected in the time-dependence of the FTIR-ATR spectra, while the further assembly of PPRs to form crystals produces characteristic reflections in the XRD patterns, due to the channel-like arrangement of CDs, that can be used to track the formation of the adduct in crystalline form. The effects that working variables have on the kinetics of the reaction, such as temperature, feed ratio, molar mass of the polymer and the introduction of an amorphous block in the polymer structure, have been investigated. The rate constants of the threading step increase with the temperature and the activation energy of the process increases at lower proportions of CD to PEG. This is attributed to the lower degree of covering of the polymer chain with CDs that reduces the hydrogen-bonding driven stabilization between adjacent macrocycles. The formation of crystalline PPR, which takes place slowly at room temperature, is markedly promoted at higher temperatures, with lower proportions of CD favoring both the formation and the growth of the crystals. The molar mass of the polymer does not modify the typical channel-like arrangement of packed PPRs but the conversion into crystalline PPR diminishes when using PEG1000 instead of PEG400. At a microscopic level, the crystals arrange into lamellar structures, in the order of hundreds of nm, embedded in an amorphous-like matrix. The introduction of a polypropylene oxide block in the structure of the polymer (Pluronic L62) renders poorer yields and a considerable loss of crystallinity of the product of the reaction. The methodology here proposed can be applied to the general case of inclusion complexes of CDs with drugs in the solid phase, or to multicomponent systems that contain polymers as excipients in pharmaceutical formulations along with CDs

Dual cholinergic signals regulate daily migration of hematopoietic stem cells and leukocytes.

Hematopoietic stem and progenitor cells (HSPCs) and leukocytes circulate between the bone marrow (BM) and peripheral blood following circadian oscillations. Autonomic sympathetic noradrenergic signals have been shown to regulate HSPC and leukocyte trafficking, but the role of the cholinergic branch has remained unexplored. We have investigated the role of the cholinergic nervous system in the regulation of day/night traffic of HSPCs and leukocytes in mice. We show here that the autonomic cholinergic nervous system (including parasympathetic and sympathetic) dually regulates daily migration of HSPCs and leukocytes. At night, central parasympathetic cholinergic signals dampen sympathetic noradrenergic tone and decrease BM egress of HSPCs and leukocytes. However, during the daytime, derepressed sympathetic noradrenergic activity causes predominant BM egress of HSPCs and leukocytes via β3-adrenergic receptor. This egress is locally supported by light-triggered sympathetic cholinergic activity, which inhibits BM vascular cell adhesion and homing. In summary, central (parasympathetic) and local (sympathetic) cholinergic signals regulate day/night oscillations of circulating HSPCs and leukocytes. This study shows how both branches of the autonomic nervous system cooperate to orchestrate daily traffic of HSPCs and leukocytes

Educational and labor wastage of doctors in Mexico: towards the construction of a common methodology

BACKGROUND: This paper addresses the problem of wastage of the qualified labor force, which takes place both during the education process and when trained personnel try to find jobs in the local market. METHODS: Secondary sources were used, mainly the Statistical yearbooks of the National Association of Universities and Higher Education Institutions (ANUIES in Spanish). Also, the 2000 Population Census was used to estimate the different sources of labor market wastage. The formulas were modified to estimate educational and labor wastage rates. RESULTS: Out of every 1000 students who started a medical training in 1996, over 20% were not able to finish the training by 2000. Furthermore, out of every 1000 graduates, 31% were not able to find a remunerated position in the labor market that would enable them to put into practice the abilities and capacities obtained at school. Important differences can be observed between generalists and specialists, as well as between men and women. In the case of specialists and men, lower wastage rates can be observed as compared to the wastage rates of generalists and women. A large percentage of women dedicate themselves exclusively to household duties, which in labor terms represents a wastage of their capacity to participate in the production of formal health services. CONCLUSION: Women are becoming a majority in most medical schools, yet their participation in the labor market does not reflect the same trend. Among men, policies should be formulated to incorporate doctors in the specific health field for which they were trained. Regarding women, specific policies should target those who are dedicated full-time to household activities in order to create the possibility of having them occupy a remunerated job if they are willing to do so. Reducing wastage at both the educational and labor levels should improve the capacity of social investment, thereby increasing the capacity of the health system as a whole to provide services, particularly to those populations who are most in need

Unconscious bias in the suppressive policing of Black and Latino men and boys: neuroscience, Borderlands theory, and the policymaking quest for just policing

his article applies neuroscience and Borderlands theory to reveal how unconscious bias currently stabilizes suppressive policing practices in America despite new efforts at reform. Illustrative cases are offered from Oakland and Santa Barbara, California, with a focus on civil gang injunctions (CGIs) and youth gang suppression. Theoretical analysis of these cases reveals how the unconscious biases of validity illusions and framing effects operate despite the best intentions of law enforcement personnel. Such unconscious or implicit biases create contradictions between the stated beliefs and actions of law enforcement. In turn, these unintended self-contradictions then work to the detriment of Latino and Black boys. The analysis here also extends to how unconscious biases and unintended self-contradictions can influence municipal policymaking in favor of suppressive police tactics such as CGIs, thereby displacing evidence-based policies that are proven to be far more effective. The article concludes with brief discussion of some of the means by which the unconscious biases – effects to which everyone is involuntarily prone – can be disrupted

A História da Alimentação: balizas historiográficas

Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

Factores de riesgo psicosocial asociados al teletrabajo, en profesores del colegio nacionalizado femenino de la ciudad de Villavicencio

El interés por los factores de riesgo psicosociales del teletrabajo en los profesores, es de alta relevancia en distintas organizaciones, con la necesidad de intervenir para mejorar la calidad de vida laboral del docente. Por consiguiente, se planteó como objetivo para esta propuesta de investigación identificar los factores de riesgo psicosociales asociados al teletrabajo en los profesores del Colegio Nacionalizado Femenino de Villavicencio-Meta. Teniendo en cuenta que el teletrabajo puede ocasionar problemas psicosociales derivados del aislamiento social, las horas excesivas de trabajo, la falta de apoyo por parte de la organización, y una alta probabilidad de dañar gravemente la salud física, social y mental. De acuerdo a esto, el tipo de metodología que se propone aplicar es de enfoque cuantitativo con un tipo diseño no experimental transversal y de alcance descriptivo. En cuanto a la muestra estará compuesta por 58 docentes del Colegio Nacionalizado Femenino de la ciudad de Villavicencio meta, que se seleccionarán de forma equitativa en cada una de las jornadas, mañana y tarde, a través de un muestreo probabilístico aleatorio simple. Es de resaltar que la selección de la muestra se realizó a través del programa STATS, en el que se determinó para garantizar la representatividad de la muestra, un nivel de confianza del 95%, un rango de error del 5% y un porcentaje de heterogeneidad del 50%.The interest in the psychosocial risk factors of telework in teachers is highly relevant in different organizations, with the need to intervene to improve the quality of work life of the teacher. Therefore, the objective of this research proposal was to identify the psychosocial risk factors associated with telework in the teachers of the Nationalized Women's College of Villavicencio-Meta. Taking into account that teleworking can cause psychosocial problems derived from social isolation, excessive hours of work, lack of support from the organization, and a high probability of seriously damaging physical, social and mental health. According to this, the type of methodology that is proposed to apply is a quantitative approach with a non-experimental cross-sectional design and descriptive scope. As for the sample, it will be made up of 58 teachers from the Nationalized Women's College of the target city of Villavicencio, who will be selected equally in each of the days, morning and afternoon, through a simple random probability sampling. It should be noted that the selection of the sample was carried out through the STATS program, in which it was determined to guarantee the representativeness of the sample, a confidence level of 95%, an error range of 5% and a percentage of heterogeneity 50%.Introducción. -- Planteamiento del problema. -- Justificación del proyecto. -- Objetivos. -- Marco de referencia. -- Metodología. -- Consideraciones éticas. -- Resultados. -- Discusiones. -- Conclusiones. -- Referencias. -- Apé[email protected]@campusucc.edu.c

Propuesta de mejora en gestión de la calidad en el uso de energía renovable del proyecto de electrificación rural, en la comunidad de Chilete - Contumaza, Región de Cajamarca

Trabado de investigacion[Originalmente sin resumen. Texto extraído del Objetivo General:] Proponer la optimización de la gestión de la calidad en el uso de energía renovable del proyecto de electrificación rural, en la comunidad de Chilete – Contumazá, región de Cajamarca- 2019