[Clinical features of Chilean patients with Fibrous Dysplasia/McCune-Albright Syndrome]. / Caracterización clínica de pacientes chilenos con displasia fibrosa/síndrome de McCune-Albright.

BACKGROUND: Fibrous Dysplasia/McCune-Albright Syndrome (FD/MAS) is characterized by a spectrum of manifestations that may include fibrous dysplasia of bone and multiple endocrinopathies. AIM: To describe the clinical spectrum, the study and follow-up of patients with FD/MAS cared at our institution. MATERIAL AND METHODS: Review of medical records of 12 pediatric and adult patients (11 women) who met the clinical and genetic diagnostic criteria for FD/ MAS. RESULTS: The patients' mean age at diagnosis was 4.9 ± 5.5 years. The most common initial clinical manifestation was peripheral precocious puberty (PPP) in 67% of patients and 75% had café-au-lait spots. Fibrous dysplasia was present in 75% of patients and the mean age at diagnosis was 7.9 ± 4.7 years. Ten patients had a bone scintigraphy, with an age at the first examination that varied between 2 and 38 years of age. The most frequent location of dysplasia was craniofacial and appendicular. No patient had a recorded history of cholestasis, hepatitis, or pancreatitis. In four patients, a genetic study was performed that was positive for the pathogenic variant of guanine nucleotide binding protein, alpha stimulating (GNAS). CONCLUSIONS: These patients demonstrate the variable nature of the clinical presentation and study of FD/MAS. It is essential to increase the index of diagnostic suspicion and adherence to international recommendations.

Smartphone-Based Analysis of Urine Reagent Strips Is Inaccurate for Assessing Underhydration.

Background: Proper hydration is vital for both exercise and general health. Although various methods for hydration assessment exist, many are not valid for either use or never tested. Introduction: The purpose of this study was to determine whether the uChek© smart phone application can be used to diagnose underhydration based on elevated urine specific gravity (USG) assessed by refractometry. Methods: One hundred forty-seven (n = 147) fresh human urine samples from young and middle-age adults were analyzed for USG with a refractometer and the uChek© application by reading the Siemens Multistix 10G urine reagent strip. Results: Bland-Altman analysis showed agreement of the two methods of assessment. Overall diagnostic ability of the uChek© to identify underhydration was fair (area under the curve 79%). However, the sensitivity to correctly identify underhydration was poor (60%) as well as the specificity of correctly identifying euhydration (53%). Conclusion: The uChek© application does not accurately detect underhydration.

Urine Reagent Strips Are Inaccurate for Assessing Hypohydration: A Brief Report.

OBJECTIVE: To assess the diagnostic ability of urine reagent strips to identify hypohydration based on urine specific gravity (USG). DESIGN: This study examined the agreement of USG between strips and refractometry with Bland-Altman, whereas the diagnostic ability of the strips to assess hypohydration was performed by receiver operating characteristic analysis. SETTING: Arkansas high school football preseason practice. PARTICIPANTS: Four hundred fourteen fresh urine samples were analyzed. MAIN OUTCOME MEASURES: Urine specific gravity was assessed by both reagent strips and refractometry. Cutoffs of >1.020 and >1.025 were used for identifying hypohydration. RESULTS: Bland-Altman analysis showed agreement of the 2 methods. Overall diagnostic ability of the urine strip to identify hypohydration was fair (area under the curve 72%-78%). However, the sensitivity to correctly identify hypohydration was poor (63%-71%), and the specificity of correctly identifying euhydration was poor to fair (68%-83%). CONCLUSION: The urine strip method is not valid for assessing hypohydration.

Simultaneous X-ray radioscopy/tomography and energy-dispersive diffraction applied to liquid aluminium alloy foams.

High-speed X-ray imaging in two dimensions (radioscopy) and three dimensions (tomography) is combined with fast X-ray diffraction in a new experimental setup at the synchrotron radiation source BESSY II. It allows for in situ studies of time-dependent phenomena in complex systems. As a first application, the foaming process of an aluminium alloy was studied in three different experiments. Radioscopy, optical expansion measurements and diffraction were used to correlate the change of foam morphology to the various phases formed during heating of an AlMg15Cu10 alloy to 620°C in the first experiment. Radioscopy was then replaced by tomography. Acquiring tomograms and diffraction data at 2 Hz allows even more details of foam evolution to be captured, for example, bubble size distribution. In a third experiment, 4 Hz tomography yields dynamic insights into fast phenomena in evolving metal foam.

Validation Testing Demonstrates Efficacy of a 7-Day Fluid Record to Estimate Daily Water Intake in Adult Men and Women When Compared with Total Body Water Turnover Measurement.

Background: Mean daily water intake from fluids (WATER-FL) has proven to be difficult to measure because of a range of nonvalidated data collection techniques. Few questionnaires have been validated to estimate WATER-FL against self-reported diaries or urinary hydration markers, which may limit their objectivity.Objectives: The goals of this investigation were 1) to assess the validity of a 7-d fluid record (7dFLR) to measure WATER-FL (WATER-FL-7dFLR) through comparison with WATER-FL as calculated by measuring deuterium oxide (D2O) disappearance (WATER-FL-D2O), and 2) to evaluate the reliability of the 7dFLR in measuring WATER-FL.Methods: Participants [n = 96; 51% female; mean ± SD age: 41 ± 14 y; mean ± SD body mass index (in kg/m2): 26.2 ± 5.1] completed body water turnover analysis over 3 consecutive weeks. They completed the 7dFLR and food diaries during weeks 2 and 4 of the observation. The records were entered into nutritional software to determine the water content of all foods and fluids consumed. WATER-FL-D2O was calculated from water turnover (via the D2O dilution method), minus water from food and metabolic water. The agreement between the 2 methods of determining WATER-FL were compared according to a Bland-Altman plot at week 2. The test-retest reliability of 7dFLR between weeks 2 and 4 was assessed via intraclass correlation (ICC).Results: The mean ± SD difference between WATER-FL-7dFLR and WATER-FL-D2O was -131 ± 845 mL/d. In addition, no bias was observed (F[1,94] = 0.484; R2 = 0.006; P = 0.488). When comparing WATER-FL-7dFLR from weeks 2 and 4, no significant difference (mean ± SD difference: 71 ± 75 mL/d; t[79] = 0.954; P = 0.343) and an ICC of 0.85 (95% CI: 0.77, 0.90) was observed.Conclusions: The main findings of this study were that the use of the 7dFLR is an effective and reliable method to estimate WATER-FL in adults. This style of questionnaire may be extremely helpful for collecting water intake data for large-scale epidemiologic studies.

The Effect of Storing Temperature and Duration on Urinary Hydration Markers.

The purpose of this investigation was to quantify the effects of storage temperature, duration, and the urinary sediment on urinary hydration markers. Thirty-six human urine samples were analyzed fresh and then the remaining sample was separated into 24 separate vials, six in each of the following four temperatures: 22 °C, 7 °C, -20 °C, and -80 °C. Two of each sample stored in any given temperature, were analyzed after 1, 2, and 7 days either following vortexing or centrifugation. Each urine sample was analyzed for osmolality (UOsm), urine specific gravity (USG), and urine color (UC). UOsm was stable at 22 °C, for 1 day (+5-9 mmol∙kg-1, p > .05) and at 7 °C, UOsm up to 7 days (+8-8 mmol∙kg-1, p > .05). At -20 and -80 °C, UOsm decreased after 1, 2, and 7 days (9-61 mmol∙kg-1, p < .05). Vortexing the sample before analysis further decreased only UOsm in the -20 °C and -80 °C storage. USG remained stable up to 7 days when samples were stored in 22 °C or 7 °C (p > .05) but declined significantly when stored in -20 °C, and -80 °C (p < .001). UC was not stable in any of the storing conditions for 1, 2, and 7 days. In conclusion, these data indicate that urine specimens analyzed for UOsm or USG remained stable in refrigerated (7 °C) environment for up to 7 days, and in room temperature for 1 day. However, freezing (-20 and -80 °C) samples significantly decreased the values of hydration markers.

Assessing the social impacts of the COVID-19 crisis using phone helplines. The case of the Balearic Islands, Spain.

Background: Crises and health policies to tackle them can increase health inequalities. We explored the scope and usefulness of helplines set up during the COVID-19 crisis and characterised the vulnerability of their users. This study explored the geographic and socioeconomic effects of the telephone helplines set up by the Balearic Islands Government and aimed to characterise the vulnerability of their users. Methods: Telephonic survey combined with a geographical analysis of a sample of calls made between 15th of March and 30th of June of 2020 to five helplines: COVID-19 general information; psychological, social (minimum vital income), labour (temporary employment regulation), and housing (rental assistance) helps. The questionnaire included sociodemographic and housing characteristics, type of problem, and if it was solved or not. We used multinomial regression to explore factors associated with having solved the problem. We calculated the standardised rate of calls by municipality using Chi-squared and z-test to test differences. Results: 1,321 interviews from 2,678 selected (231 excluded, 608 untraceable, and 518 refusals). 63.8% of women, 48.7% were born in another country. They had no internet at home in 3.1%, only on the phone in 17.3%. The 23.5% had no income at home. The Problem was solved in 25.4%, and partly in 30.9%. Factors associated with not solving the problem were not having income at home (p = 0.021), labour (p = 0.008), economic (p = 0.000) or housing (p = 0.000) problems. People from 55 of 67 municipalities did at least one call. The highest rates of calls were from coastal tourist municipalities. Conclusion: Helplines reached most of the territory of the Balearic Islands and were used mainly in tourist municipalities. It probably has not been helpful for families with more significant deprivation. Digital inequalities have emerged.

[Impact of a cardiac rehabilitation program on adherence to the mediterranean diet and physical activity in acute coronary syndrome]. / Impacto de un programa de rehabilitación cardiaca en la adherencia a la dieta mediterránea y la actividad física en el síndrome coronario agudo.

Objective: To evaluate the efficacy of a cardiac rehabilitation program (CRP) in improving adherence to non-pharmacological secondary prevention in patients with acute coronary syndrome (ACS). Method: Retrospective study of patients with ACS referred to CRP in a tertiary hospital from 2018 to 2021. Pre-post differences in adherence to physical activity, Mediterranean diet, smoking, and motivation to change were analyzed. Age, sex, and baseline motivation were analyzed in predicting change in adherence. Results: 418 patients were included. At the end of the CRP, the adherence to the mediterranean diet increased (p < 0.05; d = 0.83), frequency of physical activity increased by 2.16 (p < 0.05), and motivation to change remained constant (p = 0.94). Both women and men improved their adherence to the mediterranean diet. Both sexes performed more physical activity at the end of the CRP (1.89 times more in men and 4 times more in women; p < 0.05). An association was found between initial motivation and greater changes in adherence to the mediterranean diet (p < 0.05). An inversely proportional difference was observed between age and adherence to the mediterranean diet (p < 0.05). Conclusions: The CRP, in our hospital environment, has an effect of improving adherence to the mediterranean diet and physical exercise in patients with ACS. The change in adherence to the diet increases as the motivation to change the baseline increases, and age is inversely related to the change in adherence.

Objetivo: Evaluar la eficacia de un programa de rehabilitación cardiaca (PRC) sobre la mejora de la adherencia a las medidas de prevención secundaria no farmacológicas en pacientes con síndrome coronario agudo (SCA). Método: Estudio retrospectivo con pacientes con SCA derivados a PRC en un hospital terciario de 2018 a 2021. Se analizaron diferencias pre-post de adherencia a actividad física, dieta mediterránea, tabaquismo y motivación al cambio. Se analizaron la edad, el sexo y la motivación basal en la predicción del cambio de adherencia. Resultados: Se incluyeron 418 pacientes. Al final del PRC aumentó la adherencia a la dieta mediterránea (p < 0.05; d = 0.83), la frecuencia de actividad física aumentó 2,16 (p < 0.05) y la motivación al cambio se mantuvo constante (p = 0.94). Tanto las mujeres como los hombres mejoraron la adherencia a la dieta mediterránea. Ambos sexos realizaron más ejercicio físico al final del PRC (1.89 veces más los hombres y 4 las mujeres; p < 0.05). Se encontró una asociación entre motivación inicial y mayores cambios en la adherencia a la dieta mediterránea (p < 0.05). Se observó una diferencia inversamente proporcional entre la edad y la adherencia a la dieta mediterránea (p < 0.05). Conclusiones: El PRC, en nuestro medio hospitalario, mejora la adherencia a la dieta mediterránea y al ejercicio físico en los pacientes con SCA. La adherencia a la dieta mediterránea aumenta a medida que lo hace la motivación al cambio basal, mientras que la edad está inversamente relacionada con el cambio de adherencia.

Hierarchical radioscopy using polychromatic and partially coherent hard synchrotron radiation.

Pushing synchrotron x-ray radiography to increasingly higher image-acquisition rates (currently up to 100,000 fps) while maintaining spatial resolutions in the micrometer range implies drastically reduced fields of view. As a consequence, either imaging a small subregion of the sample with high spatial resolution or only the complete specimen with moderate resolution is applicable. We introduce a concept to overcome this limitation by making use of a semi-transparent x-ray detector positioned close to the investigated sample. The hard x-rays that pass through the sample either create an image on the first detector or keep on propagating until they are captured by a second x-ray detector located further downstream. In this way, a process can be imaged simultaneously in a hierarchical manner within a single exposure and a projection of the complete object with moderate resolution as well as a subregion with high resolution are obtained. As a proof-of-concept experiment, image sequences of an evolving liquid-metal foam are shown, employing frame rates of 1000 images/s (1.2 µm pixel size) and 15,000 images/s (18.1 µm pixel size) for the first and second detector, respectively.

Oxidation of Aqueous Phosphorous Acid Electrolyte in Contact with Pt Studied by X-ray Photoemission Spectroscopy.

The oxidation of the aqueous H3PO3 in contact with Pt was investigated for a fundamental understanding of the Pt/aqueous H3PO3 interaction with the goal of providing a comprehensive basis for the further optimization of high-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs). Ion-exchange chromatography (IEC) experiments suggested that in ambient conditions, Pt catalyzes H3PO3 oxidation to H3PO4 with H2O. X-ray photoelectron spectroscopy (XPS) on different substrates, including Au and Pt, previously treated in H3PO3 solutions was conducted to determine the catalytic abilities of selected metals toward H3PO3 oxidation. In situ ambient pressure hard X-ray photoelectron spectroscopy (AP-HAXPES) combined with the "dip-and-pull" method was performed to investigate the state of H3PO3 at the Pt|H3PO3 interface and in the bulk solution. It was shown that whereas H3PO3 remains stable in the bulk solution, the catalyzed oxidation of H3PO3 by H2O to H3PO4 accompanied by H2 generation occurs in contact with the Pt surface. This catalytic process likely involves H3PO3 adsorption at the Pt surface in a highly reactive pyramidal tautomeric configuration.

Post-Exercise Voluntary Drinking Cessation Is Associated with the Normalization of Plasma Osmolality and Thirst Perception, but Not of Urine Indicators or Net Fluid Balance.

Post-exercise rehydration has been widely studied, with particular emphasis on retention of ingested fluid; comparatively little research has been conducted on why we drink more or less. To identify physiological values corresponding to voluntary drinking cessation (VDC), nine males exercised intermittently at 70−80% HRmax in the heat (WBGT = 28.1 ± 0.7 °C) to achieve a dehydration of approximately 4.0% body mass (BM). After exercise, participants were instructed to drink water as long and as much as they needed. Urine color (Ucolor), specific gravity (USG), osmolality (Uosm), plasma osmolality (Posm), fullness, BM, and thirst perception (TP) were measured pre- and post-exercise and at VDC. Each variable was compared for the three points in time with a one-way ANOVA. Participants reached dehydration of −3.6 ± 0.3% BM. Pre-exercise USG (1.022 ± 0.004) was lower than at VDC (1.029 ± 0.004, p = 0.022), Uosm did not change over time (p = 0.217), and Ucolor was lower pre-exercise (3.4 ± 0.7) vs. post-exercise (5.5 ± 1.23, p = 0.0008) and vs. VDC (6.3 ± 1.1, p < 0.0001). Posm showed a difference between pre-exercise (289.5 ± 2.3) and post-exercise (297.8 ± 3.9, p = 0.0006) and between post-exercise and VDC (287.3 ± 5.4, p < 0.0001). TP post-exercise (96.4 ± 4.34) was significantly higher than pre-exercise (36.2 ± 19.1) and VDC (25.0 ± 18.2, p < 0.0001). At VDC, participants had recovered 58.7 ± 12.1% of BM loss. At the point of voluntary drinking cessation, Posm and thirst perception had returned to their pre-exercise values, while rehydration relative to initial BM was still incomplete.

Awareness of Fluid Losses Does Not Impact Thirst during Exercise in the Heat: A Double-Blind, Cross-Over Study.

BACKGROUND: Thirst has been used as an indicator of dehydration; however, as a perception, we hypothesized that it could be affected by received information related to fluid losses. The purpose of this study was to identify whether awareness of water loss can impact thirst perception during exercise in the heat. METHODS: Eleven males participated in two sessions in random order, receiving true or false information about their fluid losses every 30 min. Thirst perception (TP), actual dehydration, stomach fullness, and heat perception were measured every 30 min during intermittent exercise until dehydrated by ~4% body mass (BM). Post exercise, they ingested water ad libitum for 30 min. RESULTS: Pre-exercise BM, TP, and hydration status were not different between sessions (p > 0.05). As dehydration progressed during exercise, TP increased significantly (p = 0.001), but it was the same for both sessions (p = 0.447). Post-exercise water ingestion was almost identical (p = 0.949) in the two sessions. CONCLUSION: In this study, thirst was a good indicator of fluid needs during exercise in the heat when no fluid was ingested, regardless of receiving true or false water loss information.

Combining urine color and void number to assess hydration in adults and children.

BACKGROUND/OBJECTIVES: To test the diagnostic ability of two combined practical markers for elevated urine osmolality (underhydration) in free-living adults and children. SUBJECTS/METHODS: One hundred and one healthy adults (females n = 52, 40 ± 14 y, 1.70 ± 0.95 m, 76.7 ± 17.4 kg, 26.5 ± 5.5 kg/m2) and 210 children (females = 105, 1.49 ± 0.13 m, 43.4 ± 12.6 kg, 19.2 ± 3.2 kg m-2) collected urine for 24-h. Urine was analyzed for urine osmolality (UOsm), color (UC), while the number of voids (void) was also recorded. Receiver Operating Characteristic (ROC) analysis was performed for UC, void, and combination of UC and void, to determine markers' diagnostic ability for detecting underhydration based on elevated UOsm (UOsm ≥ 800 mmol kg-1). RESULTS: Linear regression analysis revealed that UC was significantly associated with UOsm in both adults (R2 = 0.38; P < 0.001) and children (R2 = 0.45; P < 0.001). Void was significantly associated with UOsm in both adults (R2 = 0.13; P < 0.001) and children (R2 = 0.15; P < 0.001). In adults, when UC > 3 and void <7 were combined, the overall diagnostic ability for underhydration was 97% with sensitivity and specificity of 100% and 88%, respectively. In children, UC > 3 and void <5 had an overall diagnostic ability for underhydration of 89% with sensitivity and specificity of 100% and 62%, respectively. CONCLUSIONS: Urine color alone and the combination of urine color with void number can a valid and simple field-measure to detect underhydration based on elevated urine osmolality.

Validity and Reliability of a Water Frequency Questionnaire to Estimate Daily Total Water Intake in Adults.

The purpose of this investigation was to assess the validity and reliability of a seven-day water frequency questionnaire (TWI-FQ) to estimate daily total water intake (TWI) in comparison to a water turnover objective reference value via deuterium oxide (D2O). Data collection occurred over 3 weeks, with a wash-out period during week two. Healthy adults (n = 98; 52% female; 41 ± 14 y; BMI, 26.4 ± 5.5 kg·m-2) retrospectively self-reported consumption frequencies of 17 liquids and 35 foods with specified volumes/amounts for weeks one and three via TWI-FQ. Standard water content values were utilized to determine the volume of water consumed from each liquid and food for calculation of mean daily TWI for each week. Diet records were completed daily during week two to estimate metabolic water production. To assess validity of the TWI-FQ, participants consumed D2O at the start of each week and provided urine samples immediately before ingestion, the following day, and at the end of the week to calculate water turnover. Metabolic water was subtracted from water turnover to estimate TWI. TWI-FQ validity was assessed via Bland-Altman plot for multiple observations. Reliability was assessed via intraclass correlation and Pearson's correlation between weeks. TWI-FQ significantly underestimated D2O TWI by -350 ± 1,431 mL·d-1 (95% confidence interval (CI): -551, -149 mL·d-1). TWI-FQ TWI was significantly correlated (r = 0.707, P <0.01) and not different (198 ± 1,180 mL·d-1, 95% CI: -38, 435 mL·d-1) between weeks. TWI-FQ intraclass correlation = 0.706 was significant [95% CI: 0.591, 0.793; F (97, 98) = 5.799], indicating moderate test-retest reliability. While this tool would not be suitable for individual TWI assessment, the magnitude of bias may be acceptable for assessment at the sample-level.

The Complete Genome Sequence of the Staphylococcus Bacteriophage Metroid.

Phages infecting bacteria of the genus Staphylococcus play an important role in their host's ecology and evolution. On one hand, horizontal gene transfer from phage can encourage the rapid adaptation of pathogenic Staphylococcus enabling them to escape host immunity or access novel environments. On the other hand, lytic phages are promising agents for the treatment of bacterial infections, especially those resistant to antibiotics. As part of an ongoing effort to gain novel insights into bacteriophage diversity, we characterized the complete genome of the Staphylococcus bacteriophage Metroid, a cluster C phage with a genome size of 151kb, encompassing 254 predicted protein-coding genes as well as 4 tRNAs. A comparative genomic analysis highlights strong similarities - including a conservation of the lysis cassette - with other Staphylococcus cluster C bacteriophages, several of which were previously characterized for therapeutic applications.

La sed ¿un mecanismo suficiente para lograr euhidratación?: una revisión narrativa / Is thirst sufficient as a mechanism for achieving euhydration? a narrative review

Capitán, C. y Aragón, L.F. (2023). La sed ¿un mecanismo suficiente para lograr euhidratación?: una revisión narrativa. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 21(1), 1-16. El papel de la percepción de sed para mantener el balance hídrico ha sido ampliamente estudiado, tanto durante el ejercicio como después de este. Sin embargo, la forma de evaluarla y la eficacia de los instrumentos existentes son aún áreas que necesitan más investigación. El objetivo de esta revisión fue integrar, de forma general, la información disponible en la literatura sobre el funcionamiento del mecanismo de la sed como respuesta a la deshidratación durante y después del ejercicio. Se explican los mecanismos fisiológicos y las respuestas de estos durante y posterior al ejercicio; además, se describen los instrumentos disponibles en la literatura científica, sus debilidades y fortalezas, y se plantea una serie de preguntas que aún no tienen respuesta en el área. En esta revisión se presenta el aspecto teórico de los mecanismos de la sed, además, se discuten los estudios científicos que respaldan o refutan el comportamiento de estos mecanismos en el ejercicio. Finalmente, se hace un resumen de las principales conclusiones extraídas de la literatura científica sobre la sed como un mecanismo suficiente para prevenir la deshidratación tanto durante como después del ejercicio.

Capitán, C. y Aragón, L.F. (2023). Is thirst sufficient as a mechanism for achieving euhydration? a narrative review. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 21(1), 1-16. The role of thirst perception for keeping hydric balance, both during and after exercise, has been extensively studied. However, the way to assess it and the effectiveness of the existing instruments are areas that still require further research. The objective of this review is to integrate, in a general way, the information available in the literature on the functioning of the thirst mechanism as a response to dehydration during and after exercise. The physiological mechanisms and their responses during and after exercise are explained. In addition, a description of the instruments available in scientific literature is included, together with their weaknesses and strengths, and a series of as yet unanswered questions in this area are raised. This review presents the theoretical aspect of thirst mechanisms, and discusses the scientific studies that support or refute the behavior of these mechanisms in exercise. Finally, a summary is made of the major conclusions drawn from the scientific literature on thirst as a sufficient mechanism to prevent dehydration both during and after exercise.

Capitán, C. y Aragón, L.F. (2023). A sede é um mecanismo suficiente para alcançar a hidratação? uma revisão narrativa. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 21(1), 1-16. O papel da percepção da sede na manutenção do equilíbrio hídrico tem sido amplamente estudado, tanto durante quanto após o exercício. Entretanto, como avaliá-la e a eficácia dos instrumentos existentes ainda são áreas que necessitam de mais pesquisas. Esta revisão visou integrar, de forma geral, as informações disponíveis na literatura sobre o funcionamento do mecanismo da sede em resposta à desidratação durante e após o exercício. Ele explica os mecanismos fisiológicos e suas respostas durante e após o exercício, descreve os instrumentos disponíveis na literatura científica, seus pontos fracos e fortes, e levanta uma série de questões que permanecem sem resposta no campo. Esta revisão apresenta o aspecto teórico dos mecanismos da sede e discute os estudos científicos que respaldam ou refutam o comportamento desses mecanismos no exercício. Finalmente, é feito um resumo das principais conclusões extraídas da literatura científica sobre a sede como mecanismo suficiente para prevenir a desidratação tanto durante quanto após o exercício.

Nanoclay Intercalation During Foaming of Polymeric Nanocomposites Studied in-Situ by Synchrotron X-Ray Diffraction.

The intercalation degree of nanoclays in polymeric foamed nanocomposites containing clays is a key parameter determining the final properties of the material, but how intercalation occurs is not fully understood. In this work, energy dispersive X-ray diffraction (ED-XRD) of synchrotron radiation was used as an in-situ technique to deepen into the intercalation process of polymer/nanoclay nanocomposites during foaming. Foamable nanocomposites were prepared by the melt blending route using low-density polyethylene (LDPE), polypropylene (PP), and polystyrene (PS) with surface treated nanoclays and azodicarbonamide (ADC) as the blowing agent. Foaming was induced by heating at atmospheric pressure. The time and temperature evolution of the interlamellar distance of the clay platelets in the expanding nanocomposites was followed. Upon foaming, interlamellar distances of the nanocomposites based on LDPE and PP increase by 18% and 16% compared to the bulk foamable nanocomposite. Therefore, the foaming process enhances the nanoclay intercalation degree in these systems. This effect is not strongly affected by the type of nanoclay used in LDPE, but by the type of polymer used. Besides, the addition of nanoclays to PP and PS has a catalytic effect on the decomposition of ADC, i.e., the decomposition temperature is reduced, and the amount of gas released increases. This effect was previously proved for LDPE.

Caracterización clínica de pacientes chilenos con displasia fibrosa/síndrome de McCune-Albright / Clinical features of Chilean patients with Fibrous Dysplasia/McCune-Albright Syndrome

BACKGROUND: Fibrous Dysplasia/McCune-Albright Syndrome (FD/MAS) is characterized by a spectrum of manifestations that may include fibrous dysplasia of bone and multiple endocrinopathies. AIM: To describe the clinical spectrum, the study and follow-up of patients with FD/MAS cared at our institution. MATERIAL AND METHODS: Review of medical records of 12 pediatric and adult patients (11 women) who met the clinical and genetic diagnostic criteria for FD/ MAS. RESULTS: The patients' mean age at diagnosis was 4.9 ± 5.5 years. The most common initial clinical manifestation was peripheral precocious puberty (PPP) in 67% of patients and 75% had café-au-lait spots. Fibrous dysplasia was present in 75% of patients and the mean age at diagnosis was 7.9 ± 4.7 years. Ten patients had a bone scintigraphy, with an age at the first examination that varied between 2 and 38 years of age. The most frequent location of dysplasia was craniofacial and appendicular. No patient had a recorded history of cholestasis, hepatitis, or pancreatitis. In four patients, a genetic study was performed that was positive for the pathogenic variant of guanine nucleotide binding protein, alpha stimulating (GNAS). CONCLUSIONS: These patients demonstrate the variable nature of the clinical presentation and study of FD/MAS. It is essential to increase the index of diagnostic suspicion and adherence to international recommendations.

Diseño y validación de una escala de actitudes hacia la Policía Nacional, para muestras colombianas / Desenho e validação de uma escala de atitudes em relação à Polícia Nacional, para amostras colombianas / Designing and Validating a Scale of Attitudes towards the National Police, for Colombian Samples

El diseño de esta investigación es de corte empírico y cuantitativo, además, es de tipo psicométrico, bajo el criterio de estudio instrumental. Su objetivo principal fue diseñar y validar una escala de actitudes hacia la Policía Nacional para una muestra colombiana. Para ello, se realizó una revisión teórica y se diseñó una tabla de especificaciones que permitió identificar la cantidad de ítems que se requerían para abarcar las seis funciones principales de dicha entidad. Posteriormente, los ítems fueron sometidos a la validación por parte de jueces, se realizaron algunos ajustes sugeridos a la escala y se aplicó la encuesta a 566 ciudadanos colombianos con edades entre los 18 y 82 años, cuya media fue de 26 años. Se tuvo acceso a la población a través de un muestreo no probabilístico por bola de nieve. Así mismo, se llevó a cabo un análisis factorial exploratorio, que agrupó los reactivos en cuatro factores: pensamientos y creencias hacia la Policía Nacional, emociones y sentimientos hacia la Policía Nacional, accionar propio de la Policía y accionar de la Policía ante riñas y peleas. Además, se realizó un análisis factorial confirmatorio que refiere adecuados índices de bondad de ajuste. Los resultados de los análisis estadísticos demostraron que este instrumento tiene una alta consistencia interna y confiabilidad, lo cual se ve reflejado en el alfa de Cronbach general de 0,875 y una adecuada validez, ya que los ítems tienen apropiados índices de extracción y los cuatro factores en los que se agruparon explican el 47,140% de la varianza total.

This study's design was empirical and quantitative. In addition, it was psychometric, under instrumental study criteria. Its main objective was to design and validate a scale of attitudes towards the National Police for a Colombian sample. To do so, a theoretical review was performed and a table of specifications was created, which allowed identifying the amount of items required to cover the six main functions of said entity. Subsequently, the ítems were submitted to validation by judges. Some suggested adjustment were made to the scale, and the survey was given to 566 Colombian citizens between the ages of 18 to 82. The average age was 26. The population was accessed by means of non-probability, snowball sampling. Moreover, an exploratory factor analysis was performed, which regrouped the reactive items into four factors: thoughts and beliefs regarding the National Police, feelings and emotions towards the National Police, the Police's own actions, and the Police's actions in light of brawls and fights. In addition, a confirmatory factor analysis that refers to proper goodness of fit indices was performed. The results of the statistical analyses demonstrated that this instrument has high internal consistency and reliability, which is reflected in the general Cronbach's alpha of 0,875 and proper validity, since the items have appropriate extraction indices and the four factors in which they were grouped explain 47,140% of total variance.

O desenho desta pesquisa é empírico e quantitativo, além disso, é psicométrico, sob o critério de estudo instrumental. Seu principal objetivo foi desenhar e validar uma escala de atitudes em relação à Polícia Nacional para uma amostra colombiana. Para isso, foi realizada uma revisão teórica e foi elaborado um quadro de especificações para identificar o número de itens necessários para cobrir as seis funções principais da referida entidade. Posteriormente, os itens foram submetidos à validação de juízes, alguns ajustes sugeridos foram feitos na escala e a pesquisa foi aplicada a 566 cidadãos colombianos com idade entre 18 e 82 anos, cuja média foi de 26 anos. A população foi acessada por amostragem não probabilística em bola de neve. Da mesma forma, foi realizada uma análise fatorial exploratória, que agrupou os itens em quatro fatores: pensamentos e crenças em relação à Polícia Nacional, emoções e sentimentos em relação à Polícia Nacional, atuação característica da Polícia e atuação da Polícia frente a rixas e brigas. Além disso, foi realizada uma análise fatorial confirmatória que se refere a índices adequados de bondade de ajuste. Os resultados das análises estatísticas demonstraram que este instrumento possui alta consistência interna e confiabilidade, o que se reflete no alfa de Cronbach geral de 0,875 e validade adequada, uma vez que os itens apresentam taxas de extração adequadas e os quatro fatores nos quais foram agrupados explicam 47,140% da variância total.