Application of approximation theory by nonlinear manifolds in Sturm-Liouville inverse problems

We give here some negative results in Sturm-Liouville inverse theory, meaning that we cannot approach any of the potentials with $m+1$ integrable derivatives on $\mathbb{R}^+$ by an $\omega$-parametric analytic family better than order of $(\omega\ln\omega)^{-(m+1)}$. Next, we prove an estimation of the eigenvalues and characteristic values of a Sturm-Liouville operator and some properties of the solution of a certain integral equation. This allows us to deduce from [Henkin-Novikova] some positive results about the best reconstruction formula by giving an almost optimal formula of order of $\omega^{-m}$.Comment: 40 page

Introduction to the special section "Techniques of stability of fuzzy control systems"

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Blood flow measurements in rats using four color microspheres during blockade of different vasopressor systems

The use of colored microspheres to adequately evaluate blood flow chancres under different circumstances in the same rat has been validated with a maximum of three different colors due to methodological limitations. the aim of the present study was to validate the use of four different colors measuring four repeated blood flow. changes in the same rat to assess the role of vasopressor systems in. controlling arterial pressure (AP). Red (150,000), white (200,000)), yellow (150,000), and blue (200,000) colored microspheres were infused into the left ventricle of 6 male Wistar rats 1) at rest and 2) after vasopressin (aAVP, 10 mug/kg, iv), 3) renin-angiotensin (losartan, 10 ms/kg iv), and 4) sympathetic system blockade (hexamethonium., 20 mg/kg, iv) to determine blood flow changes. AP was recorded and processed with a data acquisition system (1-kHz sampling frequency). Blood flow changes were quantified by spectrophotometry absorption peaks for colored microsphere components in the tissues evaluated. Administration of aAVP and losartan slightly reduced the AP (-5.7 +/- 0.5 and -7.8 +/- 1.2 mmHg, respectively), while hexamethonium induced a 52 +/- 3 mmHg fall in AP. the aAVP injection increased blood flow in lungs (78%), liver (117%) and skeletal muscle (>150%), while losartan administration enhanced blood flow in heart (126%), lungs (100%), kidneys (80%), and gastrocnemius (75%) and soleus (94%) muscles. Hexamethonium administration reduced only kidney blood flow (50%). in conclusion, four types of colored microspheres can be used to perform four repeated blood flow measurements in the same rat detecting small alterations such as changes in tissues with low blood flow.Univ São Paulo, Fac Med, Inst Coracao, Unidade Hipertensao, BR-05403000 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Nefrol, São Paulo, BrazilUniv Santo Amaro, UNIPESQ, Santo Amaro, SP, BrazilUniv Sao Judas Tadeu, Lab Movimiento Humano, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Nefrol, São Paulo, BrazilWeb of Scienc

Estudio funcional del cortisol y ACTH plasmáticos en perros : respuesta ante el estímulo con hormona liberadora de corticotrofina (CRF) en situación de anestesia

La acción de los agentes anestésicos sobre la ACTH y el cortisol es variable. Nos interesó ver el comportamiento del eje hipotálarno-hipófisoadrenal en situación de anestesia. Igualmente se estudia la capacidad de respuesta de este eje cuando, estando bajo el efecto de la anestesia, se somete a un estímulo fisiológico. Se observa que el pentotal sódico produce descenso del nivel de cortisol y ACTH.Aún estando el animal anestesiado, las glándulas adrenales tienen capacidad de respuesta ante estímulos fisiológicosThe action of the anaesthetic agents on ACTH and cortisol is variable. In the present paper we were interested to see the behauiour of the hypothalamus bypophysis-adrenal axis in a state of anaesthesia. In the same way we study the response capacity of this axis when, being under the effect of anaesthesia, it is submitted to a physiological stimulus. We observe sodium pentothal produces a decrease in the level of cortisol and ACTH. Even when the animal is anaesthetized, the adrenal glands have the response capacity in the presence of physiological stimuli

Screening of substance use and mental health problems among Spanish medical students: A multicenter study

Background: This study aimed to determine the prevalence of substance consumption and mental health problems among Spanish medical students, and their association with sociodemographic factors. Methods: A multicentre cross-sectional study was conducted. Self-reported data on sociodemographic and clinical characteristics were collected, including BDI-II, PHQ-9, brief STAI, and single-item academic burnout (IUBA). Results: Overall, 1265 students (74.2% female) completed the survey. Of them, 37.4% scored positive for depressive symptoms, as measured by the BDI-II, and more than half (53%) by the PHQ-9. Suicidal ideation was reported by about 12% whilst high levels of state and trait anxiety were informed by 28.8% and 29.4% of the students. The prevalence of burnout was 40.2%. Female and pre-clinical students reported significantly (p < 0.01) higher rates of depressive, anxiety, and burnout symptoms. Alcohol, energy drinks, and tobacco were the most frequently used substances. Total scores of self-reported mental health problems negatively correlated (p < 0.001) with objective academic results and positively correlated (p < 0.02) with the number of substances consumed in the last 30 days. Limitations: Research-based on self-reported data could favour information bias due to the social desirability effect and memory error. Conclusions: A high prevalence of substance consumption and several mental health problems was found among medical students, especially females. The relevant influence of academic-related factors on students' well-being may be a call for medical schools to implement initiatives aimed to improve students' ability to detect, address, and seek help for their mental health issues

Ubiquitinación de proteínas nucleares en la señalización del ayuno de fosfato en plantas

Comunicaciones a congreso

EJERCICIO PROFESIONAL Y TENDENCIA A LA EMIGRACIÓN EN EGRESADOS DE LA FOLP

Los graduados de nuestras facultades son el vínculo entre el sistema de Educación Superior y la sociedad, sin embargo una vez que egresan, nada se sabe de sus inquietudes, de las fortalezas y debilidades de su formación, de sus necesidades de perfeccionamiento y de los problemas que enfrentan en su inserción en el mercado laboral. El objetivo del presente trabajo es analizar la propensión a la emigración, los motivos de la misma y el tiempo de desempleo desde la graduación en egresados de la Facultad de Odontología de la UNLP. Es un estudio transversal de tipo descriptivo, el universo lo constituyeron los egresados de la FOLP en el período 1998-1999, pertenecientes a los planes 1990 – 1994, las fuentes documentales: CESPI y Secretaría de Post-grado de la FOLP. La información se obtuvo mediante una encuesta estructurada que se aplicó vía correo postal, internet y entrevistas personales y telefónicas. De un total de 648 egresados, 318 del año 1998 y 330 del año 1999, se obtuvo información de 199 del año 1998 (62.58%) y de 1999, 214 que corresponde al 64.85%. Las encuestas brindaron elementos para determinar que un alto porcentaje de egresados estuvo desempleado por más de seis meses desde que se graduó, teniendo intención de emigrar por problemas laborales y/o económicos