594 research outputs found
Local and regional heterogeneity underlying hippocampal modulation of cognition and mood.
While the hippocampus has been classically studied for its role in learning and memory, there is significant support for a role of the HPC in regulating emotional behavior. Emerging research suggests these functions may be segregated along the dorsoventral axis of the HPC. In addition to this regional heterogeneity, within the HPC, the dentate gyrus is one of two areas in the adult brain where stem cells continuously give rise to new neurons. This process can influence and be modulated by the emotional state of the animal, suggesting that adult neurogenesis within the DG may contribute to psychiatric disorders and cognitive abilities. Yet, the exact mechanism by which these newborn neurons influence behavior remains unknown. Here, we will examine the contribution of hippocampal neurogenesis to the output of the HPC, and suggest that the role of neurogenesis may vary along the DV axis. Next, we will review literature indicating that anatomical connectivity varies along the DV axis of the HPC, and that this underlies the functional segregation along this axis. This analysis will allow us to synthesize novel hypotheses for the differential contribution of the HPC to cognition and mood
Physical Inactivity and Mortality Risk
In recent years a plethora of epidemiologic evidence accumulated supports a strong, independent and inverse, association between physical activity and the fitness status of an individual and mortality in apparently healthy individuals and diseased populations. These health benefits are realized at relatively low fitness levels and increase with higher physical activity patterns or fitness status in a dose-response fashion. The risk reduction is at least in part attributed to the favorable effect of exercise or physical activity on the cardiovascular risk factors, namely, blood pressure, diabetes mellitus and obesity. In this review, we examine evidence from epidemiologic and interventional studies in support of the association between exercise and physical activity and health. In addition, we present the exercise effects on the aforementioned risk factors. Finally, we include select dietary approaches and their impact on risk factors and overall mortality risk
THE USE AND SYMBOLISM OF ANIMALS IN THE WONDERFUL WIZARD OF OZ
This paper is the result of a qualitative research that follows an animal-based interpretative theory. It sheds the light on the use and symbolism of animal characters in The Wonderful Wizard of Oz written by L. Frank Baum and published in 1900. It seems to be a modern fairy tale with an American setting and charming fantasy characters. It is an immensely popular text among children and adults, so it is considered a classic of children's literature. It also attempts to answer why and how Baum used animals; whether for their qualities or for the sake of creating characters opposite to their symbolism. Therefore, the role and function of animal characters are extensively discussed. The findings show how L. Frank Baum presents a distinguished world from a non-human perspective and at the same time he teaches morality, religion, and accepting diversity in nature in an exciting narrative full of adventures. These animal characters can serve as a symbolic role models for young readers.
Hypothermia in bleeding trauma: a friend or a foe?
The induction of hypothermia for cellular protection is well established in several clinical settings. Its role in trauma patients, however, is controversial. This review discusses the benefits and complications of induced hypothermia--emphasizing the current state of knowledge and potential applications in bleeding patients. Extensive pre-clinical data suggest that in advanced stages of shock, rapid cooling can protect cells during ischemia and reperfusion, decrease organ damage, and improve survival. Yet hypothermia is a double edged sword; unless carefully managed, its induction can be associated with a number of complications. Appropriate patient selection requires a thorough understanding of the pre-clinical literature. Clinicians must also appreciate the enormous influence that temperature modulation exerts on various cellular mechanisms. This manuscript aims to provide a balanced view of the published literature on this topic. While many of the advantageous molecular and physiological effects of induced hypothermia have been outlined in animal models, rigorous clinical investigations are needed to translate these promising findings into clinical practice
Enhanced fitness and renal function in Type 2 diabetes.
Aims
To investigate the renal effects of fitness in people with diabetes with mild renal dysfunction. Methods
The effect of a 12-week exercise programme on estimated GFR in 128 people with diabetes was evaluated. Results
All cardiometabolic variables improved after 12 weeks of supervised exercise. Although there was a modest 3.9% increase in estimated GFR from baseline in the 128 people who completed the study, those with baseline chronic kidney disease stages 2 and 3 were found to have significant (6 and 12%, respectively; p \u3c 0.01) improvements in post-exercise estimated GFR. Moreover, 42% of the people with chronic kidney disease stage 3 improved to chronic kidney disease stage 2 after the intervention. Conclusion
Short-term exercise improves renal function in those with more moderate baseline chronic kidney disease. Thus, renal function appears to be responsive to enhanced physical fitness. Being a strong and modifiable risk factor, enhanced fitness should be considered a non-pharmacological adjunct in the management of diabetic kidney disease
Spatial variability in levels of benzene, formaldehyde, and total benzene, toluene, ethylbenzene and xylenes in New York City: a land-use regression study
Background Hazardous air pollutant exposures are common in urban areas contributing to increased risk of cancer and other adverse health outcomes. While recent analyses indicate that New York City residents experience significantly higher cancer risks attributable to hazardous air pollutant exposures than the United States as a whole, limited data exist to assess intra-urban variability in air toxics exposures. Methods To assess intra-urban spatial variability in exposures to common hazardous air pollutants, street-level air sampling for volatile organic compounds and aldehydes was conducted at 70 sites throughout New York City during the spring of 2011. Land-use regression models were developed using a subset of 59 sites and validated against the remaining 11 sites to describe the relationship between concentrations of benzene, total BTEX (benzene, toluene, ethylbenzene, xylenes) and formaldehyde to indicators of local sources, adjusting for temporal variation. Results Total BTEX levels exhibited the most spatial variability, followed by benzene and formaldehyde (coefficient of variation of temporally adjusted measurements of 0.57, 0.35, 0.22, respectively). Total roadway length within 100 m, traffic signal density within 400 m of monitoring sites, and an indicator of temporal variation explained 65% of the total variability in benzene while 70% of the total variability in BTEX was accounted for by traffic signal density within 450 m, density of permitted solvent-use industries within 500 m, and an indicator of temporal variation. Measures of temporal variation, traffic signal density within 400 m, road length within 100 m, and interior building area within 100 m (indicator of heating fuel combustion) predicted 83% of the total variability of formaldehyde. The models built with the modeling subset were found to predict concentrations well, predicting 62% to 68% of monitored values at validation sites. Conclusions Traffic and point source emissions cause substantial variation in street-level exposures to common toxic volatile organic compounds in New York City. Land-use regression models were successfully developed for benzene, formaldehyde, and total BTEX using spatial indicators of on-road vehicle emissions and emissions from stationary sources. These estimates will improve the understanding of health effects of individual pollutants in complex urban pollutant mixtures and inform local air quality improvement efforts that reduce disparities in exposure
Study of Mechanical Strength Characteristics For Roller Compacted Concrete with Recycled Aggregates
Recycled aggregates have globally proven to be extremely flexible to use in various engineering applications after they have previously been used exclusively for laying foundations in road works, backfilling and soil replacement for improvement, but the accelerated urban development that necessitated consumption of large quantities of aggregates has led specialists to find methods which aimed to take advantage of the huge quantities produced annually from demolition and construction waste and converted them to gravel that will form a reservist to natural ones for being used in various types of structural concrete, such as roller compacted concrete.
This research focuses on producing compacted concrete using different proportions of recycled aggregates, and studying its mechanical strengths (Compressive Strength, Splitting Tensile Strength, Flexural Tensile Strength) to determine how they are affected by the replacement process.
The research found that the use of recycled aggregates in producing of compacted concrete seems very positive. With a 50% replacement rate, achieved relatively higher compressive strength values, noting that the values that were expected to be low, as the splitting tensile strength and flexural tensile Strength, looked very good for this Type of concrete compared with that identical of concrete manufactured with natural aggregates.
أثبتت الحصويّات المعاد تدويرها عالميّاً مرونةً كبيرة للاستعمال في مختلف التطبيقاتٍ الهندسيّة بعد أن اقتصر استعمالها سابقاً على طبقات التأسيس في الأعمال الطرقية، لكنّ التطّور العمراني المتسارع الذي استوجب استهلاك كميّات كبيرة من الحصويّات دفع المختصيّن إلى إيجاد منهجيّات تهدف للاستفادة من الكميّات الهائلة المنتجة سنويّاً من نفايات الهدم والإنشاء وتحويلها لحصويات تشكّل رديفاً للحصويّات الطبيعية بهدف استعمالها في مختلف أنواع البيتون الإنشائي كالبيتون المرصوص بالمداحي.
يركّز هذا البحث على إنتاج بيتون مرصوص باستعمال نسبٍ مختلفةٍ من الحصويّات المعاد تدويرها، ودراسة مقاوماته الميكانيكيّة (المقاومة على الضغط البسيط، مقاومة الشد بالفلق، مقاومة الشد بالانعطاف) للوقوف على مدى تأثّرها بعمليّة الاستبدال.
توصّل البحث إلى أنّ استخدام الحصويّات المعاد تدويرها في إنتاج البيتون المرصوص يبدو إيجابيّاً جدّاً، حيث حقّقت نسبة الاستبدال 50% قيماً أعلى نسبيّاً للمقاومة على الضغط البسيط مع الإشارة إلى أنّ القيم التي كان يتوقّع أن تكون منخفضةً كالمقاومة على الشد بالانعطاف والشدّ بالفلق بدت جيّدةً جدّاً لهذا النوع من البيتون مقارنةً مع مثيلاتها للبيتون المصنّع باستخدام حصويّاتٍ طبيعيّة
Predictors of 6-month mortality among nursing home residents: Diagnoses maybe more predictive than functional disability
Objective: Loss of daily living functions can be a marker for end of life and possible hospice eligibility. Unfortunately, data on patient\u27s functional abilities is not available in all settings. In this study we compare predictive accuracy of two indices designed to predict 6-month mortality among nursing home residents. One is based on traditional measures of functional deterioration and the other on patients\u27 diagnoses and demography.
Methods: We created the Hospice ELigibility Prediction (HELP) Index by examining mortality of 140,699 Veterans Administration (VA) nursing home residents. For these nursing home residents, the available data on history of hospital admissions were divided into training (112,897 cases) and validation (27,832 cases) sets. The training data were used to estimate the parameters of the HELP Index based on (1) diagnoses, (2) age on admission, and (3) number of diagnoses at admission. The validation data were used to assess the accuracy of predictions of the HELP Index. The cross-validated accuracy of the HELP Index was compared with the Barthel Index (BI) of functional ability obtained from 296,052 VA nursing home residents. A receiver operating characteristic curve was used to examine sensitivity and specificity of the predicted odds of mortality.
Results: The area under the curve (AUC) for the HELP Index was 0.838. This was significantly (α \u3c0.01) higher than the AUC for the BI of 0.692.
Conclusions: For nursing home residents, comorbid diagnoses predict 6-month mortality more accurately than functional status. The HELP Index can be used to estimate 6-month mortality from hospital data and can guide prognostic discussions prior to and following nursing home admission
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