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Central Chile is undergoing its most severe drought since 2010, affecting ecosystems, water supply, agriculture, and industrial uses. The government's short-term measures, such as increasing groundwater extraction (by 383 % from 1997 to 2022), are exacerbating the situation, leading to long-term hydrological deterioration. The objective of this research is to establish the main processes driving the water table depth evolution within Central Chile over the period 1979-2023. This is done by conducting groundwater balances on five major hydrological basins of Central Chile. For the Megadrought (MD) period (2010-2022), the groundwater level depths reflect not only the recharge variability but, especially, the forcing trend of groundwater withdrawals: they represent 35 % and 65 %, respectively, of the total phreatic level drawdown. This result underlines the dominant role played by groundwater withdrawals in the current delicate state of Central Chile's groundwater resources, while revealing that drought is a new complex phenomenon to deal with, in the midterm, to revert the current water resource trend in Central Chile. Our study moreover presents the impact of climate change in the basin in the framework of six different groundwater withdrawal scenarios. In the worst case (i.e., RCP8.5), the aquifer recharge decreases 18 % with respect to 1979-1997, which is the period assumed to be unaffected by the impact of MD and withdrawals. Such a reduction may be irrelevant in the dynamics of the aquifer system if the current extraction rate does not change. The estimated recovery time needed to reach aquifer conditions equal to those of the unaffected period is approximately 50 years.

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El tratamiento quirúrgico del cáncer de mama puede dejar secuelas tardías tales como escápula alada, pérdida de movilidad articular del hombro, sobrepeso, etc. Basado en lo anterior, el objetivo del presente estudio fue describir las secuelas morfofuncionales en mujeres operadas de cáncer de mama de las regiones de la Araucanía y del Bío-Bío, Chile, explorando también si el procedimiento quirúrgico conllevaría a la presencia de escápula alada. Para ello, se realizó un estudio cuantitativo, observacional y de corte transversal en treinta mujeres operadas de cáncer de mama, de edades comprendidas entre 28 y 76 años (55,67±11,60). Un profesional entrenado evaluó peso, estatura, índice de masa corporal (IMC), índice de cintura cadera (ICC), rangos articulares de hombro (ROM, Range of Movement) y fuerza prensil, aplicándose además la prueba de Hoppenfeld para identificar escápula alada. Los resultados mostraron diferencias significativas en el ROM a la abducción de hombro (p<0,05), correlación significativa positiva de leve (r=0,370) a moderada (r=0,514) entre el ROM del lado afectado tanto para la flexión como la abducción con la fuerza prensil. Destacan, un IMC de 28,91±5,31 kg/m2, un ICC de 0,86±0,06 cm y la presencia de escápula alada en el 36,7 % de las participantes. No se encontró asociación entre el abordaje quirúrgico y la presencia de escápula alada. Hubo secuelas morfo-funcionales en las mujeres en estudio, destacándose las alteraciones en el rango de movimiento del miembro superior, sobrepeso, riesgo cardiovascular y la presencia de escápula alada, sin asociarse al tipo de abordaje quirúrgico.

Surgical treatment of breast cancer can leave late sequelae such as winged scapula, loss of joint mobility of the shoulder, overweight, etc. Based on the above, the objective of the present study was to describe the morpho-functional sequelae in women operated on for breast cancer from the regions of Araucanía and Del BíoBío, Chile, also exploring whether the surgical procedure would lead to the presence of scapula winged. For this, a quantitative, observational and cross-sectional study was conducted in thirty women operated on for breast cancer, aged between 28 and 76 years (55.67 ± 11.60). A trained professional evaluated weight, height, body mass index (BMI), hip waist index (ICC), shoulder joint ranges(ROM, Range of Movement) and prehensile strength, and applied the Hoppenfeld test to identify the winged scapula. The results showed significant differences in the ROM to shoulder abduction (p <0.05), positive significant correlation of mild (r = 0.370) to moderate (r = 0.514) between the ROM of the affected side for both flexion and abduction with prehensile force. Highlights, a BMI of 28.91 ± 5.31 kg / m2, an ICC of 0.86 ± 0.06 cm and the presence of winged scapula in 36.7 % of the participants. No association was found between the surgical approach and the presence of the winged scapula. There were morphofunctional sequelae in the women under study, highlighting the alterations in the range of movement of the upper limb, overweight, cardiovascular risk and the presence of the winged scapula, without being associated with the type of surgical approach.

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INTRODUCCIÓN: Frecuentemente se agrega una artrodesis intersomática a la artrodesis posterolateral en el tratamiento quirúrgico de la espondilolistesis degenerativa. Sin embargo, la real utilidad de esta medida no está clara. MÉTODOS: Para responder esta pregunta utilizamos Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante búsquedas en múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, reanalizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES: Identificamos cuatro revisiones sistemáticas que en conjunto incluyen nueve estudios primarios, de los cuales ninguno corresponde a un ensayo aleatorizado. Concluimos que agregar una artrodesis intersomática a una artrodesis posterolateral en el tratamiento quirúrgico de la espondilolistesis degenerativa podría asociarse a una disminución en el deslizamiento del cuerpo vertebral y a una leve mejoría de la calidad de vida de los pacientes, pero asociado también a un mayor costo.

INTRODUCTION: Surgical treatment of lumbar degenerative spondylolisthesis usually involves an interbody fusion in addition to a posterolateral fusion. However, the value of this procedure has not been established. METHODS: To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS: We identified four systematic reviews, including nine primary studies; none of them randomized. We concluded performing interbody fusion in addition to posterolateral fusion during the surgical treatment of lumbar degenerative spondylolisthesis might decrease vertebral body slippage and lead to a slight improvement in quality of life. However, it is associated with higher costs.

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The investigation assesses the influence of recent climatic events in the water resources and the aquifer dynamics in the Huasco watershed by means of the analysis of precipitation, streamflow and piezometric levels during the last 50years. These hydrological and hydrogeological parameters were evaluated by an exploratory geostatistical analysis (semivariogram) and a spectral analysis (periodogram). Specifically, the hydrological and hydrogeological data analyses are organized according to three sub-basins, the Del Carmen River (Section I), the El Tránsito River (Section II), and the Huasco River (Section III). Data ranges for rainfall are from 1961 to 2015, for streamflow from 1964 to 2015, and for groundwater levels from 1969 to 2014, available from Water Authority of Chile. The analyses allowed the identification of cycles in the hydrological and hydrogeological records. The study area is located in a transient climatic fringe where the convergence of several climatic systems can be identified in the hydrological and hydrogeological records. Results indicate that the nival areas and the small glaciers are especially important to the recharge processes in the Huasco watershed during the spring-summer snowmelting. Water reservoirs in the main aquifer (Section III) and in the Santa Juana dam are highly sensitive to ENSO oscillation climatic patterns. The main climatic events that control this record are the El Niño and La Niña events. In addition, the climatic influence of the westerlies and the SE extratropical moisture were also identified. Spectral analysis identified the presence of a 22.9-yearcycle in piezometric levels of the alluvial aquifer of the Huasco River. This cycle is consistent with the 22-year Hale solar cycle, suggesting the existence of a solar forcing controlling the ENSO oscillations. Moreover, semivariogram and spectral analysis identified a 10.65-yearcycle and a 9.2-yearcycle in groundwater, respectively, which were attributed to the strong mode of ENSO oscillations.

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El Departamento de Extensión Universitaria de la Universidad de Buenos Aires desarrolló, entre otras, una experiencia piloto con población desfavorecida en una zona urbana del Gran Buenos Aires. Estaba orientada a mejorar la calidad de vida de sus habitantes a partir de su propia participación en la resolución de sus problemas vitales; y a ofrecer a diversas Cátedras y Departamentos de la Universidad de Buenos Aires un espacio de formación profesional para sus estudiantes y graduados. A partir del análisis de fuentes documentales escritas de época y testimonios actuales de protagonistas de la experiencia, se caracterizan las concepciones pedagógicas y didácticas que fundamentaban los diversos programas y dispositivos educativos implementados tanto para promover el desarrollo comunitario como para abordar las problemáticas educativas de niños, jóvenes y adultos...

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BACKGROUND: Circumferential lumbar spinal fusion is widely used to increase fusion rate, but little data is available using fresh-frozen femoral head allograft (FFFHA) as a structural interbody graft alternative. HYPOTHESIS: Circumferential lumbar arthrodesis using FFFHA as interbody graft material could be an alternative to achieve interbody fusion without graft subsidence. METHODS: A retrospective review of 47 patients (56 levels) treated with lumbar circumferential fusion using FFFHA as interbody material. Consolidation was independently assessed by the two authors using a 3-type scale; interbody bone graft subsidence was also evaluated. RESULTS: Forty-four of the 47 patients (93.6%), and 53 of the 56 levels (94.6%) obtained consolidation, without differences between smokers and nonsmokers. Three levels (in three patients) did not fuse; one of them (2.1%) required revision. No patient presented graft dislodgment, signs of infection or graft subsidence at the last follow-up. DISCUSSION: FFFHA use as lumbar interbody graft in circumferential arthrodesis exhibited a 94% fusion rate, without graft subsidence. FFFHA may be considered a valid alternative to achieve interbody fusion. LEVEL OF EVIDENCE: Level IV. Retrospective study.

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A continuous model of a metabolic network including gene regulation to simulate metabolic fluxes during batch cultivation of yeast Saccharomyces cerevisiae was developed. The metabolic network includes reactions of glycolysis, gluconeogenesis, glycerol and ethanol synthesis and consumption, the tricarboxylic acid cycle, and protein synthesis. Carbon sources considered were glucose and then ethanol synthesized during growth on glucose. The metabolic network has 39 fluxes, which represent the action of 50 enzymes and 64 genes and it is coupled with a gene regulation network which defines enzyme synthesis (activities) and incorporates regulation by glucose (enzyme induction and repression), modeled using ordinary differential equations. The model includes enzyme kinetics, equations that follow both mass-action law and transport as well as inducible, repressible, and constitutive enzymes of metabolism. The model was able to simulate a fermentation of S. cerevisiae during the exponential growth phase on glucose and the exponential growth phase on ethanol using only one set of kinetic parameters. All fluxes in the continuous model followed the behavior shown by the metabolic flux analysis (MFA) obtained from experimental results. The differences obtained between the fluxes given by the model and the fluxes determined by the MFA do not exceed 25% in 75% of the cases during exponential growth on glucose, and 20% in 90% of the cases during exponential growth on ethanol. Furthermore, the adjustment of the fermentation profiles of biomass, glucose, and ethanol were 95%, 95%, and 79%, respectively. With these results the simulation was considered successful. A comparison between the simulation of the continuous model and the experimental data of the diauxic yeast fermentation for glucose, biomass, and ethanol, shows an extremely good match using the parameters found. The small discrepancies between the fluxes obtained through MFA and those predicted by the differential equations, as well as the good match between the profiles of glucose, biomass, and ethanol, and our simulation, show that this simple model, that does not rely on complex kinetic expressions, is able to capture the global behavior of the experimental data. Also, the determination of parameters using a straightforward minimization technique using data at only two points in time was sufficient to produce a relatively accurate model. Thus, even with a small amount of experimental data (rates and not concentrations) it was possible to estimate the parameters minimizing a simple objective function. The method proposed allows the obtention of reasonable parameters and concentrations in a system with a much larger number of unknowns than equations. Hence a contribution of this study is to present a convenient way to find in vivo rate parameters to model metabolic and genetic networks under different conditions.

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Introducción: la posibilidad de identificar pacientes HER2 positivo y poder ofrecerles una terapia específica ha cambiado el pronóstico y la evolución de las mismas, es por ello que la determinación de sobreexpresión de HER2 es una factor clave para la toma de decisiones en el tratamiento del cáncer de mama. Objetivo: recolectar datos locales de la incidencia de la sobreexpresión de HER2 en la población con cáncer de mama de reciente diagnóstico y datos de anatomía patológica y la relación de los mismos con la sobreexpresión de HER2. Materiales y método: estudio epidemiológico que recolecta datos de las fichas de anatomía patológica y de las historias clínicas de pacientes con cáncer de mama operadas entre agosto de 2006 y agosto de 2007. De las biopsias previamente realizadas de rutina en pacientes operadas, se tomó un extendido para la determinación de HER2 por inmunohistoquímica (IHQ) con un anticuerpo policlonal anti HER2 (Dako), recuperación antigénica en microondas, sistema de detección En Vision (Dako) y revelado con diaminobenzidina. Para interpretar los resultados se usó el score de ASCO/CAP. Resultados: ingresaron 342 pacientes, HER negativo, 285 pacientes (83%); dudoso, 19 pacientes (6%); y HER2 positivo, 38 pacientes (11%). La edad promedio fue de 63,7 años. Se compararon las características clínicas y anatomopatológicas de ambas poblaciones (Tabla I). Conclusiones: la incidencia de HER2 positivo fue inferior (11%) a las reportadas en otras series, probablemente influida por el tamaño de la muestra o por el estadio inicial de las pacientes.

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Introducción: la posibilidad de identificar pacientes HER2 positivo y poder ofrecerles una terapia específica ha cambiado el pronóstico y la evolución de las mismas, es por ello que la determinación de sobreexpresión de HER2 es una factor clave para la toma de decisiones en el tratamiento del cáncer de mama. Objetivo: recolectar datos locales de la incidencia de la sobreexpresión de HER2 en la población con cáncer de mama de reciente diagnóstico y datos de anatomía patológica y la relación de los mismos con la sobreexpresión de HER2. Materiales y método: estudio epidemiológico que recolecta datos de las fichas de anatomía patológica y de las historias clínicas de pacientes con cáncer de mama operadas entre agosto de 2006 y agosto de 2007. De las biopsias previamente realizadas de rutina en pacientes operadas, se tomó un extendido para la determinación de HER2 por inmunohistoquímica (IHQ) con un anticuerpo policlonal anti HER2 (Dako), recuperación antigénica en microondas, sistema de detección En Vision (Dako) y revelado con diaminobenzidina. Para interpretar los resultados se usó el score de ASCO/CAP. Resultados: ingresaron 342 pacientes, HER negativo, 285 pacientes (83%); dudoso, 19 pacientes (6%); y HER2 positivo, 38 pacientes (11%). La edad promedio fue de 63,7 años. Se compararon las características clínicas y anatomopatológicas de ambas poblaciones (Tabla I). Conclusiones: la incidencia de HER2 positivo fue inferior (11%) a las reportadas en otras series, probablemente influida por el tamaño de la muestra o por el estadio inicial de las pacientes.

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