645 research outputs found
Studies of the binding strengths and modes of action of organic ligands on aluminium trihydroxide surfaces
Decision-making Techniques for Community Groups
Community groups often have a problem coming to a decision about projects to undertake. Quite often, resources, both human and financial, are limited; the number of problems seem overwhelming; or there are forceful advocates of a "pet" project. How can a group overcome these difficulties? The four decision-making techniques shown in this guide will make the task easier. The first two techniques generate ideas about community goals or projects while the last two prioritize the alternatives you have identified.New 6/92/5M
Town Meetings that Work
Town meetings -- The nature of community -- Orgainizing a town meeting -- The town meeting process -- Final thoughts -- AppendiciesNew 4/93/lM.Includes bibliographical reference
Human treadmill walking needs attention
BACKGROUND: The aim of the study was to assess the attentional requirements of steady state treadmill walking in human subjects using a dual task paradigm. The extent of decrement of a secondary (cognitive) RT task provides a measure of the attentional resources required to maintain performance of the primary (locomotor) task. Varying the level of difficulty of the reaction time (RT) task is used to verify the priority of allocation of attentional resources. METHODS: 11 healthy adult subjects were required to walk while simultaneously performing a RT task. Participants were instructed to bite a pressure transducer placed in the mouth as quickly as possible in response to an unpredictable electrical stimulation applied on the back of the neck. Each subject was tested under five different experimental conditions: simple RT task alone and while walking, recognition RT task alone and while walking, walking alone. A foot switch system composed of a pressure sensitive sensor was placed under the heel and forefoot of each foot to determine the gait cycle duration. RESULTS: Gait cycle duration was unchanged (p > 0.05) by the addition of the RT task. Regardless of the level of difficulty of the RT task, the RTs were longer during treadmill walking than in sitting conditions (p < 0.01) indicating that an increased amount of resources are required for the maintainance of walking performance on a treadmill at a steady state. No interaction (p > 0.05) was found between the attentional demand of the walking task and the decrement of performance found in the RT task under varying levels of difficulty. This finding suggests that the healthy subjects prioritized the control of walking at the expense of cognitive performance. CONCLUSION: We conclude that treadmill walking in young adults is not a purely automatic task. The methodology and outcome measures used in this study provide an assessment of the attentional resources required by walking on the treadmill at a steady state
Conservation in Countries with Multiple Crisis Factors: The Case of Los Katios National Natural Park, a World Humanity Heritage in Danger
Conservation biology aims to stop habitat loss and extinction of species. To achieve these goals there are several methods such as the establishment of natural reserves and national parks that in synthesis work as protected areas. However, the management of areas with high conservation priorities can be a challenge to conservation biology and all of the professionals involved in this process.
The Colombian National Natural Park, Los Katios, hosts more than the 20% of Colombian biodiversity and is located in a region which is characterised as being one of the most biodiverse and endemic points on the planet. The park was declared a World Humanity Heritage Area in 1994 by the United Nations Educational, Scientific and Cultural Organization (UNESCO) and on the 8th of July 2009, the Colombian government solicited to the UNESCO World Heritage Committee the inclusion of the park on the list of World Heritage in Danger due to the pressures from illegal activities and inefficient surveillance in the area.
Through the case of study of Los Katios National Natural Park, this review looks explores the extent to which the socio-economic situation and the internal crises of a country can influence the effectiveness of the conservation programs in protected areas. It also explains the relevance of National Natural Parks and the effects that some factors, such as violence; illegal crops; poverty; and environmental budget, can have on the performance of the conservation biology.
This review concludes that the conservation of protected areas in countries with deep internal crises, such as in the case of Los Katios in Colombia, cannot be based solely on the fundamental conservation goals and that it is necessary to include government priorities and some strategies to counteract social issues as violence, poverty and insufficient funds when creating management plans
Using visible and near infrared spectroscopy to estimate carbonates and gypsum in soils in arid and subhumid regions of Isfahan, Iran
Soils in arid and semi-arid regions are strongly affected by the accumulation of carbonates, gypsum and other, more soluble, salts. Carbonates and gypsum both have a considerable influence on soil properties, especially the chemical properties of the soil solution. The development of reliable, fast and inexpensive methods to quantify the amounts of carbonates and gypsum in soil is therefore
important. Visible and near infrared (vis-NIR) spectroscopy is a non-destructive, rapid and cheap method for measuring several soil properties simultaneously. However, research on vis-NIR spectroscopy in quantifying carbonates and gypsum is limited. Therefore, this study evaluated the efficiency of vis-NIR spectroscopy in quantifying carbonates and gypsum in surface soils using partial least-squares regression (PLSR) compared with standard laboratory methods and compared PLSR with a feature-specific method using continuum removal (CR). Carbonates and gypsum in a total of 251 sieved and air-dried topsoil samples from Isfahan Province in central Iran were measured by standard laboratory methods and vis-NIR spectroscopy (350â2500 nm wavelength range). In parallel, PLSR and the feature-specific method based on CR spectra were used to predict carbonates and gypsum. The PLSR model efficiency (E) for carbonates and gypsum in the validation set was 0.52 and 0.80, respectively. The PLSR model resulted in better predictions than the feature-specific method for both soil properties. Because of the unique absorption features of gypsum, which did not overlap with other soil properties, predictions of gypsum resulted in higher E values and lower errors than predictions of carbonates
Decision-making techniques for community groups
"Community groups often have a problem coming to a decision about projects to undertake. Quite often, resources, both human and financial, are limited; the number of problems seem overwhelming; or there are forceful advocates of a 'pet' project. How can a group overcome these difficulties? The four decision-making techniques shown in this guide will make the task easier. The first two techniques generate ideas about community goals or projects, while the last two prioritize the alternatives you have identified."--Page 1.Reviewed by Sarah Hultine Massengale (Community Economic Development). Johanna Reed Adams, Charles M. St. Clair and William E. Robertson (Department of Community Development)Reviewed 03/202
Serum neopterin levels in relation to mild and severe COVID-19
Background: The COVID-19 pandemic, caused by the coronavirus SARS-CoV-2, is rapidly spreading worldwide. There is limited information about prognostic markers that could help clinicians to identify COVID-19 patients with a poor prognosis. Serum levels of the immune activation marker neopterin has shown to be of prognostic value in patients with SARS. The aim of this study was to investigate whether serum neopterin is associated with the severity of COVID-19. Methods: We included 34 patients with confirmed COVID-19 between March 3 and March 30, 2020. Fifteen patients had mild disease and did not require hospitalization, whereas 19 patients developed severe COVID-19 requiring intensive care. Concentrations of serum neopterin, tryptophan, and kynurenine were measured at and repeatedly after inclusion. Results: We found a more than two-fold higher mean concentration of neopterin in severely ill patients (mean value 42.0 nmol/L (SD 18.2)) compared to patients with mild symptoms (16.9 nmol/L (SD 11.0)). All of the severe cases had elevated neopterin concentrations (> 9.1 nmol/L) at the initial sampling with values ranging from 17.2 to 86.7 nmol/L. In comparison, 10 of 15 patients with mild disease had neopterin levels above 9.1 nmol/L, with concentrations in the range from 4.9 to 31.6 nmol/L. Neopterin levels gradually decreased during the course of COVID-19, but severe cases maintained elevated levels for a longer period. Moreover, lower levels of tryptophan and higher levels of kynurenine, indicating an increased tryptophan catabolism, were seen in the group with severe cases. Conclusions: In conclusion, we found that serum neopterin levels are associated with the severity of COVID-19. Our findings suggest that neopterin could be used as a prognostic marker, but further studies are needed to elucidate how it can be used in the clinic
Social Media Use: Attitudes, "Detox," and Craving in Typical and Frequent Users
Social media has become a core feature of daily life, with 4.8 billion users worldwide. Research on individual differences in social media use has tended to focus on the effect of differing levels of engagement on specific mental health outcomes. In contrast, few studies have directly investigated usersâ own perceptions of the impact of their social media use, attempts to regulate their behavior through periods of âdetox,â and the drivers that compel them to return to these platforms. Therefore, in this study, we examined usersâ current attitudes toward their social media use, their awareness of the impact it had on other aspects of their lives, their experiences of self-initiated periods of âdetox,â and their reasons for reengagement. A sample of 208 U.K. social media users (aged 18â28), partitioned into typical and frequent user groups using the Social Media Addiction Questionnaire and the Social Media Engagement Questionnaire, were tested on all measures. The findings, derived from both quantitative and qualitative data, showed that users across both groups were aware of the impact of overuse, and they were able to successfully engage in sustained periods of social media detox, from which they derived positive effects (e.g., on sleep, mood, productivity), and the primary driver for continued use was a desire for social connectedness and information rather than a âcravingâ for social media per se. Taken together, these findings provide novel data on usersâ perceptions of their social media use and, in particular, evidence in support of the positive benefits of periods of social media âdetox.
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