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Temperate perennial fruit and nut trees play varying roles in world food diversity-providing edible oils and micronutrient, energy, and protein dense foods. In addition, perennials reuse significant amounts of biomass each year providing a unique resilience. But they also have a unique sensitivity to seasonal temperatures, requiring a period of dormancy for successful growing season production. This paper takes a global view of five temperate tree fruit crops-apples, cherries, almonds, olives, and grapes-and assesses the effects of future temperature changes on thermal suitability. It uses climate data from five earth system models for two CMIP6 climate scenarios and temperature-related indices of stress to indicate potential future areas where crops cannot be grown and highlight potential new suitable regions. The loss of currently suitable areas and new additions in new locations varies by scenario. In the southern hemisphere (SH), end-century (2081-2100) suitable areas under the SSP 5-8.5 scenario decline by more than 40% compared to a recent historical period (1991-2010). In the northern hemisphere (NH) suitability increases by 20% to almost 60%. With SSP1-2.6, however, the changes are much smaller with SH area declining by about 25% and NH increasing by about 10%. The results suggest substantial restructuring of global production for these crops. Essentially, climate change shifts temperature-suitable locations toward higher latitudes. In the SH, most of the historically suitable areas were already at the southern end of the landmass limiting opportunities for adaptation. If breeding efforts can bring chilling requirements for the major cultivars closer to that currently seen in some cultivars, suitable areas at the end of the century are greater, but higher summer temperatures offset the extent. The high value of fruit crops provides adaptation opportunities such as cultivar selection, canopy cooling using sprinklers, shade netting, and precision irrigation.
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Cambio Climático , Frutas , Temperatura , Fitomejoramiento , Frío , Productos AgrícolasRESUMEN
Irrigated agriculture in Mediterranean areas faces tremendous challenges because of its exposure to hydroclimatic variability, increasing competition for water from different sectors, and the possibility of a climatic change. In this context, efficient management of water resources emerges as a critical issue. This requires the adoption of technological innovations, investment in infrastructure, adequate institutional arrangements, and informed decision makers. To understand farmers' perceptions and their implementation of climate change adaptation strategies with regards to water management, primary information was captured in the Limarí and Maule river basins in Chile. Farmers identified stressors for agriculture; climate change, droughts, and lack of water appeared as the most relevant stressors compared to others productive, economic, and institutional factors; revealing a rising relevance of climate related factors. While most producers perceived climate changes in recent years (92.9 %), a significant proportion (61.1 %) claim to have experienced drought, whereas only a fraction (31.9 %) have implemented a strategy to deal with this situation. Identified actions were classified in four groups: investments for water accumulation, modernization of irrigation systems, rationalization of water use, and partnership activities. Using a multinomial logit model these strategies were related to socioeconomic and productive characteristics. Results show that gender and farm size are relevant for investments, implementation and improvement of irrigation systems. For all the strategies described, access to weather information was a relevant element. The study provides empirical evidence of a recent increase in the importance assigned to climate factors by producers and adaptation options that can be supported by agricultural policy.
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Riego Agrícola/organización & administración , Cambio Climático , Ríos , Recursos Hídricos/provisión & distribución , Chile , Clima , Sequías , Agricultores/psicología , Humanos , Percepción , Abastecimiento de AguaRESUMEN
Time series of vegetation indices and remotely sensed phenological data offer insights about the patterns in vegetation dynamics. Both are useful sources of information for analyzing and monitoring ecosystem responses to environmental variations caused by natural and anthropogenic drivers. In the semi-arid region of Chile, climate variability and recent severe droughts in addition to land-use changes pose threats to the stability of local ecosystems. Normalized difference vegetation index time series (2000-2013) data from the moderate resolution imaging spectroradiometer (MODIS) was processed to monitor the trends and patterns of vegetation productivity and phenology observed over the last decade. An analysis of the relationship between (i) vegetation productivity and (ii) precipitation and temperature data for representative natural land-use cover classes was made. Using these data and ground measurements, productivity estimates were projected for two climate change scenarios (RCP2.6 and RCP8.5) at two altitudinal levels. Results showed negative trends of vegetation productivity below 2000 m a.s.l. and positive trends for higher elevations. Phenology analysis suggested that mountainous ecosystems were starting their growing period earlier in the season, coinciding with a decreased productivity peak during the growing season. The coastal shrubland/grassland land cover class had a significant positive relation with rainfall and a significant negative relation with temperature, suggesting that these ecosystems are vulnerable to climate change. Future productivity projections indicate that under an RCP8.5 climate change scenario, productivity could decline by 12% in the period of 2060-2100, leading to a severe vegetation degradation at lower altitudes and in drier areas.
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Cambio Climático , Desarrollo de la Planta , Altitud , Chile , Clima , Sequías , Ecosistema , Monitoreo del Ambiente , Pradera , Ríos , Imágenes Satelitales , Estaciones del Año , TemperaturaRESUMEN
AIM: To compare electromyographic (EMG) activity in young-adult subjects with different breathing types. METHODOLOGY: This study included 50 healthy male subjects with complete natural dentition, and no history of orofacial pain or craniomandibular-cervical-spinal disorders. Subjects were classified into two groups: upper costal breathing type, and costo-diaphragmatic breathing. Bipolar surface electrodes were located on sternocleidomastoid, diaphragm, external intercostal, and latissimus dorsi muscles. Electromyographic activity was recorded during the following tasks: (1) normal quiet breathing; (2) speaking the word 'Mississippi'; (3) swallowing saliva; and (4) forced deep breathing. RESULTS: Sternocleidomastoid and latissimus dorsi EMG activity was not significantly different between breathing types, whereas diaphragm and external intercostal EMG activity was significantly higher in the upper costal than costo-diaphragmatic breathing type in all tasks (P<0·05; Wilcoxon signed rank-sum test). CONCLUSION: Diaphragm and external intercostal EMG activity suggests that there could be differences in motor unit recruitment strategies depending on the breathing type.
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Diafragma/fisiología , Músculos del Cuello/fisiología , Músculos Respiratorios/fisiología , Adolescente , Adulto , Electromiografía , Voluntarios Sanos , Humanos , Masculino , RespiraciónRESUMEN
BACKGROUND: Each year, 1.2 million metalworkers are exposed to metalworking fluids (MWFs), which can cause dermal and respiratory disease. The National Institute for Occupational Safety and Health (NIOSH) conducted a health hazard evaluation of MWF exposures at an aircraft engine manufacturing facility. The objectives were to determine employee exposures to endotoxin and MWFs in the air, characterize symptoms experienced by employees working with MWFs, compare them to symptoms of employees unexposed to MWFs, and make recommendations for reducing exposures based on results. METHODS: Four hundred seven workers were categorized as MWF exposed or MWF unexposed and completed questionnaires. Estimated prevalence ratios (PR) of dermatitis, asthma, and work-related asthma (WRA) symptoms were calculated. Airborne concentrations of MWF and endotoxin were measured, and work practices observed. RESULTS: MWF exposed workers had a significantly higher prevalence of dermatitis on wrists/forearms (PR 2.59; 95% CI 1.22, 5.46), asthma symptoms (PR 1.49; 95% CI 1.05, 2.13), and WRA symptoms (PR 2.10; 95% CI 1.22, 3.30) than unexposed workers. Airborne concentrations of MWF were below the NIOSH recommended exposure limit (REL) for MWF aerosols (thoracic particulate mass). CONCLUSIONS: Despite MWF exposures below the NIOSH REL, exposed workers had a higher prevalence of asthma, WRA, and dermatitis symptoms than unexposed workers. Recommendations to reduce exposure included configuring mist collectors to automatically turn on when the machine is in use, and enforcing enclosure use.
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Asma Ocupacional/epidemiología , Dermatitis Profesional/epidemiología , Metalurgia , Adolescente , Adulto , Anciano , Contaminantes Ocupacionales del Aire/análisis , Aeronaves , Femenino , Humanos , Exposición por Inhalación , Masculino , Persona de Mediana Edad , Valores Limites del Umbral , Adulto JovenRESUMEN
Surface water quality has increasing importance worldwide and is particularly relevant in the semiarid North-Central Chile, where agriculture and mining activities are imposing heavy pressure on limited water resources. The current study presents the application of a water quality index in four watersheds of the 29°-33°S realm for the period 1999-2008, based on the Canadian Council of Ministers for the Environment approach and the Chilean regulation for irrigation water quality. In addition, two modifications to the index are tested and a comprehensive characterization of the existing monitoring network is performed through cluster analysis. The basins studied show fairly good water quality in the overall, specially the Limarí basin. On the other hand, the lower index values were obtained for the headwaters of Elqui, associated with the El Indio mining district. The first modification of the indicator (i.e., to consider parameters differentially according to their effect on human health or the environment) did not produce major differences with respect to the original index, given the generally good water quality. The second modification (i.e., to consider as threshold values the more restrictive figures derived from a set of regulations) yielded important differences in the indicator values. Finally, an adequate characterization of the monitoring network was obtained. The results presented spatial coherence and the information can be used as a basis for the optimization of the monitoring network if required.
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Contaminantes Químicos del Agua/análisis , Calidad del Agua/normas , Riego Agrícola , Chile , Clima , Análisis por Conglomerados , Monitoreo del Ambiente/legislación & jurisprudencia , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/estadística & datos numéricos , Metales Pesados/análisis , Contaminación Química del Agua/estadística & datos numéricosRESUMEN
Reliable estimates of the impacts of climate change on crop production are critical for assessing the sustainability of food systems. Global, regional, and site-specific crop simulation studies have been conducted for nearly four decades, representing valuable sources of information for climate change impact assessments. However, the wealth of data produced by these studies has not been made publicly available. Here, we develop a global dataset by consolidating previously published meta-analyses and data collected through a new literature search covering recent crop simulations. The new global dataset builds on 8703 simulations from 202 studies published between 1984 and 2020. It contains projected yields of four major crops (maize, rice, soybean, and wheat) in 91 countries under major emission scenarios for the 21st century, with and without adaptation measures, along with geographical coordinates, current temperature and precipitation levels, projected temperature and precipitation changes. This dataset provides a solid basis for a quantitative assessment of the impacts of climate change on crop production and will facilitate the rapidly developing data-driven machine learning applications.
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This contribution analyzes water chemical data for the Choapa basin, North Central Chile, for the period 1980-2004. The parameters considered are As, Cu Fe, pH, EC, SO4⻲, Cl⻹, and HCO[Formula: see text], from samples taken in nine monitoring stations throughout the basin. Results show rather moderate contents of As, Cu, and Fe, with the exception of the Cuncumén River and the Aucó creek, explained by the influence of the huge porphyry copper deposit of Los Pelambres and by the presence of mining operations, respectively. When compared against results obtained in previous researches at the neighboring Elqui river basin, which host the El Indio Au-Cu-As district, a much reduced grade of pollution is recognized for the Choapa basin. Considering the effect of acid rock drainage (ARD)-related Cu contents on the fine fraction of the sediments of both river basins, the differences recorded are even more striking. Although the Los Pelambres porphyry copper deposit, on the headwaters of the Choapa river basin, is between one and two orders of magnitude bigger than El Indio, stream water and sediments of the former exhibit significantly lower copper contents than those of the latter. A main factor which may explain these results is the smaller degree of H( + )-metasomatism on the host rocks of the Los Pelambres deposit, where mafic andesitic volcanic rocks presenting propylitic hydrothermal alteration are dominant. This fact contrast with the highly altered host rocks of El Indio district, where most of them have lost their potential to neutralize ARD.
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Monitoreo del Ambiente , Minería , Contaminantes Químicos del Agua/análisis , Tampones (Química) , Chile , Sedimentos Geológicos/química , Concentración de Iones de Hidrógeno , Ríos/química , Contaminantes Químicos del Agua/química , Contaminación Química del Agua/estadística & datos numéricosRESUMEN
In recent decades, hemophilia A treatment has been focused on body weight, without taking pharmacokinetic parameters into account. Previous research has shown that the individual pharmacokinetic response is more effective in predicting the required dose of clotting factor. We want to evaluate the impact on reducing the frequency of bleeding in patients treated with recombinant factor VIII, based on a personalized comprehensive management program. Our aim was to compare the results of a standard comprehensive treatment program (stage I) vs. a personalized pharmacokinetic - based treatment program (stage II) in a cohort of 60 patients with severe hemophilia without inhibitors. The median age was 15.5 years (3-68). The annual bleeding rate (ABR) was 1.03 (62 episodes) in the first stage and 0.58 (35 episodes) in the second one, (p=0.004). By type of bleeding, the impact of the intervention differs significantly in spontaneous bleeding (p=0.007) and a 73% reduction in the first stage. There were no significant differences in traumatic bleeding. The use of pharmacokinetics (PK) for personalized dosing of patients with severe hemophilia A, significantly reduces ABR and spontaneous bleeding, improving the patient's quality of life and costs for the health system.
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Introducción: Las cicatrices hipertróficas (CH) y queloides (QU) corresponden al resultado de una cicatrización patológica en la piel, que afectan la calidad de vida de quienes las presentan. Su tratamiento considera diversas intervenciones, muchas de las cuales son de alto costo y/o poco predecibles. Entre ellas, la toxina botulínica (TB) podría tener un efecto a nivel preventivo, aunque los resúmenes de evidencia presentan resultados disímiles. Por esto, proponemos sintetizar la evidencia proveniente de revisiones sistemáticas (RS) y metaanálisis (MA) de ensayos clínicos aleatorizados (ECA) sobre los efectos de la inyección local de TB en la prevención de CH y QU en pacientes que recibieron o recibirán un trauma quirúrgico en la piel. Métodos y análisis: Revisión panorámica siguiendo la declaración PRIOR. Ejecutaremos la búsqueda en la base de datos Epistemonikos. Realizaremos la selección de estudios, extracción de datos y evaluación de la calidad de las RS por duplicado. Compararemos las revisiones a través de matrices de evidencia, incluyendo las RS que aborden una pregunta similar y los ECA incluidos en estas. Estimaremos la superposición entre revisiones mediante el método de área cubierta y área cubierta corregida. Ética y difusión: No se requiere aprobación ética. Esta revisión se publicará después de un proceso de revisión por pares. Sus resultados podrían ser utilizados por personal de salud para informar decisiones individuales y por tomadores de decisión de servicios de salud para guiar la asignación de recursos.
Introduction: Hypertrophic scars (HS) and keloids (KE) result from an aberrant reparative process in the skin, impacting the quality of life of those who are affected by them. Their treatment consists of different interventions, many of which are costly and/or have unpredictable results. Among them, botulinum toxin (BT) might have a preventive effect, although current evidence summaries show varying results. Therefore, we aim to synthesize the evidence coming from systematic reviews (SRs) and meta-analyses (MA) of randomized controlled trials (RCTs) on the effects of local injection of TB in the prevention of HS and KE formation in patients after a surgical wound of the skin. Methods and analysis: This will be an overview of SRs following PRIOR statement. We will conduct the search in Epistemonikos Database. Two reviewers will independently conduct the screening of articles for inclusion, quality appraisal and data extraction. We will compare the SRs using an evidence matrix, including SRs that address this topic, and the RCTs included in them. We will estimate the overlap between them using the covered area method and corrected covered area index. Ethics and dissemination: Ethics approval is not required. This review will be published after a peer-review process. The results will inform areas of future research and could be used by health personnel to make individual decisions, and by healthcare managers, administrators, and policymakers to guide resource allocation.
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Biosphere-atmosphere water and carbon fluxes depend on ecosystem structure, and their magnitudes and seasonal behavior are driven by environmental and biological factors. We studied the seasonal behavior of net ecosystem CO2 exchange (NEE), Gross Primary Productivity (GPP), Ecosystem Respiration (RE), and actual evapotranspiration (ETa) obtained by eddy covariance measurements during two years in a Mediterranean Acacia savanna ecosystem (Acacia caven) in Central Chile. The annual carbon balance was -53 g C m-2 in 2011 and -111 g C m-2 in 2012, showing that the ecosystem acts as a net sink of CO2, notwithstanding water limitations on photosynthesis observed in this particularly dry period. Total annual ETa was of 128 mm in 2011 and 139 mm in 2012. Both NEE and ETa exhibited strong seasonality with peak values recorded in the winter season (July to September), as a result of ecosystem phenology, soil water content and rainfall occurrence. Consequently, the maximum carbon assimilation rate occurred in wintertime. Results show that soil water content is a major driver of GPP and RE, defining their seasonal patterns and the annual carbon assimilation capacity of the ecosystem, and also modulating the effect that solar radiation and air temperature have on NEE components at shorter time scales.
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Introducción: Constantin von Economo reportó en 1917 múltiples casos de manifestaciones neurológicas secundarias a la pandemia de la gripe española, clasificándolos en tres grandes grupos: forma somnolienta-oftalmopléjica, mutismo y la hipercinética, con secuelas similares a la enfermedad de Parkinson. Objetivo: presentar un caso de reciente aparición de patología rara en Cali, Colombia con manejo adecuado en unidad de cuidados intensivos (UCI). Presentación del caso: paciente de 9 años con disminución de la fuerza en extremidades, disartria y somnolencia, que inició deterioro neurológico progresivo requiriendo manejo en UCI. El equipo multidisciplinario diagnosticó encefalitis letárgica e iniciaron manejo con plasmaféresis e inmunosupresión con mejoría significativa. Discusión y conclusiones: como la prevalencia es escasa, el diagnóstico exige un alto índice de sospecha como la ocurrencia de un cuadro infeccioso previo al inicio de los síntomas, ya que se considera una reacción autoinmune cruzada contra antígenos de la sustancia nigra. En algunos casos hay alteraciones en los estudios imagenológicos o en citoquímico de líquido cefalorraquídeo. El manejo con pulsos de metilprednisolona y filtración de plasma con plasmaféresis brinda mejoría significativa con disminución de las secuelas a futuro.
Introduction: In 1917, Constantin von Economo reported multiple cases of neurological manifestations secondary to the Spanish flu pandemic. He classified them into three main clinical forms: somnolent-ophthalmoplegic, mutism and hyperkinetic, causing sequelae resembling Parkinson Ìs disease. Objective: to present a case of a recent appearance rare disease entity, in Cali Colombia, receiving appropriate management in the Intensive Care Unit (ICU). Case presentation: 9-year-old patient presenting with limb muscle weakness, dysarthria and somnolence, evidencing progressive neurological deterioration requiring admission to the ICU for management. A diagnosis of encephalitis lethargica (EL) was made by the attending multidisciplinary team and management with plasmapheresis and immunosuppression was started, obtaining significant improvement. Discussion and conclusions: as the prevalence is low, the diagnosis requires a high level of suspicion in cases presenting with infectious conditions prior to the development of symptoms, since it is considered an autoimmune cross-reaction against substantia nigra antigens. Alterations in brain imaging or in cerebrospinal fluid cytometry may be found in some cases. Management with methylprednisolone pulse therapy and filtration plasmapheresis provides significant improvement with a decrease in future sequelae.
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Humanos , Femenino , Niño , Enfermedad de Parkinson Posencefalítica , Encefalitis de San Luis , Fiebre , Autoinmunidad , Gripe HumanaRESUMEN
Introducción. El manejo de la hidrocefalia habitualmente comprende la derivación del líquido cefalorraquídeo hacia alguna cavidad corporal. En circunstancias especiales, los pacientes requieren de abordajes alternos y el cirujano se enfrenta al empleo de opciones extremas. Caso clínico. En este estudio se presentan dos pacientes que se sometieron quirúrgicamente a una derivación ventrículo-cava a través de un acceso vascular periférico. Conclusiones. La técnica representó un abordaje de fácil aplicación y con mínimas complicaciones que nos brinda una opción de rescate en aquellos pacientes complicados. En los casos presentados, el empleo de esta técnica fue exitoso.
Background. Hydrocephalus management usually involves cerebrospinal fluid shunting into some corporal cavity. Under special circumstances, patients require alternate approaches, and the surgeon faces the use of extreme options. Case report. In this study we present two patients who were surgically approached with ventriculocaval shunt through peripheral vascular access. Conclusions. The technique represented an easy application with minimal complications, an approach that provides a rescue option in cases of complicated hydrocephalus. In our case, this technique was successful.