120 research outputs found

    Macroeconomic drivers of baseline scenarios in dynamic CGE models: review and guidelines proposal

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    For dynamic computable general equilibrium (CGE) modeling, long-term baseline construction is key and depends on the applied methods and the sources of projections considered. For dynamic CGE models, baseline assumptions and base data are both important determinants of results. This paper reviews the assumptions made by 24 modeling teams on baseline macroeconomic drivers, understood as factor accumulation and gross domestic product (GDP) growth. We critically review the various methods, identifying state-of-the-art practices and propose simple guidelines, particularly focusing on consistency between data sources and models, which is intended to help dynamic CGE modelers build their own baselines

    Coral bleaching under thermal stress: putative involvement of host/symbiont recognition mechanisms

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    <p>Abstract</p> <p>Background</p> <p>Coral bleaching can be defined as the loss of symbiotic zooxanthellae and/or their photosynthetic pigments from their cnidarian host. This major disturbance of reef ecosystems is principally induced by increases in water temperature. Since the beginning of the 1980s and the onset of global climate change, this phenomenon has been occurring at increasing rates and scales, and with increasing severity. Several studies have been undertaken in the last few years to better understand the cellular and molecular mechanisms of coral bleaching but the jigsaw puzzle is far from being complete, especially concerning the early events leading to symbiosis breakdown. The aim of the present study was to find molecular actors involved early in the mechanism leading to symbiosis collapse.</p> <p>Results</p> <p>In our experimental procedure, one set of <it>Pocillopora damicornis </it>nubbins was subjected to a gradual increase of water temperature from 28°C to 32°C over 15 days. A second control set kept at constant temperature (28°C). The differentially expressed mRNA between the stressed states (sampled just before the onset of bleaching) and the non stressed states (control) were isolated by Suppression Subtractive Hybridization. Transcription rates of the most interesting genes (considering their putative function) were quantified by Q-RT-PCR, which revealed a significant decrease in transcription of two candidates six days before bleaching. RACE-PCR experiments showed that one of them (<it>PdC-Lectin</it>) contained a C-Type-Lectin domain specific for mannose. Immunolocalisation demonstrated that this host gene mediates molecular interactions between the host and the symbionts suggesting a putative role in zooxanthellae acquisition and/or sequestration. The second gene corresponds to a gene putatively involved in calcification processes (<it>Pdcyst-rich</it>). Its down-regulation could reflect a trade-off mechanism leading to the arrest of the mineralization process under stress.</p> <p>Conclusion</p> <p>Under thermal stress zooxanthellae photosynthesis leads to intense oxidative stress in the two partners. This endogenous stress can lead to the perception of the symbiont as a toxic partner for the host. Consequently, we propose that the bleaching process is due in part to a decrease in zooxanthellae acquisition and/or sequestration. In addition to a new hypothesis in coral bleaching mechanisms, this study provides promising biomarkers for monitoring coral health.</p

    Propuesta estratégica de comunicaciones de marketing para generar valor de marca de la empresa constructora Albert y Hns S.R.L. en la ciudad de Trujillo - 2015

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    El presente estudio se ha realizado con el objetivo de proponer estrategias de comunicación de marketing aplicables a la empresa constructora “Albert Y Hns S.R.L”, la cual permitirá generar valor de marca. La problemática del presente trabajo de investigación, radica en generar valor de marca a la empresa, para la cual se diseñó una PROPUESTA DE ESTRATEGIAS DE COMUNICACIÓN DE MARKETING aplicable en base a los aspectos más sensibles reflejados en la investigación. Se utilizaron como técnicas de recolección de datos, la encuesta y la entrevista; para determinar si la empresa utiliza estrategias de comunicación de marketing y el grado de valor de marca de la empresa. Se concluyó que la empresa carece de actividades de comunicación claramente definidas, lo cual incide en el valor de la marca, escasa transmisión de identidad y ausencia de reconocimiento de la marca lo cual implica que esta no posea valor.The present research was conducted with the aim to propose communication strategies applicable to the construction company ""Albert Y Hns S.R.L"" which will generate brand equity. The problem of this research is to generate brand equity to the company, for which a PROPOSAL OF COMMUNICATION MARKETING STRATEGIES applicable based on the most sensitive aspects reflected in research designed. They were used as technician for data collection, survey and interview; to determine whether the company uses marketing communication strategies and the degree of brand value of the company. It was concluded that the company lacks clearly defined communication activities, which affects the value of the brand, poor transmission of identity, lack differentiation from other companies and lack of brand recognition which means that this does not have valueTesi

    The Achilles tendon is mechanosensitive in older adults: adaptations following 14 weeks versus 1.5 years of cyclic strain exercise.

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    The aging musculoskeletal system experiences a general decline in structure and function, characterized by a reduced adaptability to environmental stress. We investigated whether the older human Achilles tendon (AT) demonstrates mechanosensitivity (via biomechanical and morphological adaptations) in response to long-term mechanical loading. Thirty-four female adults (60-75 years) were allocated to either a medium-term (14 weeks; N=21) high AT strain cyclic loading exercise intervention or a control group (N=13), with 12 participants continuing with the intervention for 1.5 years. AT biomechanical properties were assessed using ultrasonography and dynamometry. Tendon cross-sectional area (CSA) was investigated by means of magnetic resonance imaging. A 22% exercise-related increment in ankle plantarflexion joint moment, along with increased AT stiffness (598.2±141.2 versus 488.4±136.9 N mm(-1) at baseline), Young's modulus (1.63±0.46 versus 1.37±0.39 GPa at baseline) and about 6% hypertrophy along the entire free AT were identified after 14 weeks of strength training, with no further improvement after 1.5 years of intervention. The aging AT appears to be capable of increasing its stiffness in response to 14 weeks of mechanical loading exercise by changing both its material and dimensional properties. Continuing exercise seems to maintain, but not cause further adaptive changes in tendons, suggesting that the adaptive time-response relationship of aging tendons subjected to mechanical loading is nonlinear

    Stretch imposed on active muscle elicits positive adaptations in strain risk factors and exercise-induced muscle damage

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    INTRODUCTION Stretching highly-contracted plantar flexor muscles (isokinetic eccentric contractions) results in beneficial adaptations in muscle strain risk factors; however its effects in other muscle groups, and on architectural characteristics and exercise-induced muscle damage (EIMD), are unknown. METHODS The influence of a 6-week knee extensor training program was studied in 26 volunteers (13 control; 13 experimental). Before and after the training program, passive and maximal isometric and eccentric knee extensor moments and range of motion (ROM) were recorded on an isokinetic dynamometer with simultaneous ultrasound imaging of vastus lateralis (VL). On a separate day, EIMD markers (creatine kinase [CK], delayed onset muscle soreness [DOMS]) were measured before and 24 hours after a 20-minute downhill run. The 6-week training program was performed twice-weekly where five sets of 12 stretches (3 seconds per stretch) were imposed on maximally contracted knee extensor muscles. RESULTS Significant (P  0.05) in passive muscle-tendon stiffness (-9.4%) or resting fascicle length (-0.7%) occurred. The downhill run resulted in substantial DOMS and significant increase in CK concentration before the training program (107.6%); however, DOMS was eliminated from the knee extensors and a significantly smaller increase in CK (-70.0%) occurred post-training. CONCLUSION Positive adaptations in functional and physiological variables confirm that imposing stretch on maximally contracted muscle provides beneficial adaptations likely to mitigate EIMD and injury risk and enhance functional performance

    Implementation of a Parser Generator.

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