6,773 research outputs found
SCIENCES SERVICES, MANAGEMENT AND ENGINEERING: ONE ANSWER TO THE EMERGENT SERVICES SECTOR
The sector services are already the most important in the economy of the developed societies. In spite of it, the discussion on the professional management goes very late regarding the social and economic necessities of the organizations and the society. As part of this society, the University needs to elaborate answers to the demands of this emergent sector. At the beginning of this century a combined university and managerial discussion originated an academic new discipline: "Science, management and engineering of the services (SSME). In this work the role of the university in the development of this Science is presente
Vestibulocochlear toxicity in a pair of siblings 15 years apart secondary to aspartame: two case reports
Effects of anxiety on neurocognitive performance in HIV positive adults
Objective: To examine the effects of anxiety on neuropsychological performance among HIV positive adults in Lusaka, Zambia.Design: A cross-sectional study with a sample of 263 participants of who 107 (40.7%) were males and 156 (59.3%) were females.Measures: The International Neurobehavioural Test Battery and Beck Anxiety Inventory were used to assess cognitive performance and anxiety levels respectively.Results: Severe anxiety showed a weak positive correlation (r=.148, p=0.472), but the result did not reach statistical significance. Participants who were not able to perform instrumental activities of daily living independently were more likely to be anxious (p<0.05).Conclusion: Results obtained from this study imply that there are minimal differences in performance between non anxious and anxious HIV positive individuals on neurocognitive performance. However, anxiety showed an effect on instrumental activities of daily living of the participants.Key Words: Anxiety, HIV, instrumental activities of daily living, Cognitive Performanc
Revisiting the history, concepts and typologies of community management for rural drinking water supply in India
Community management has been widely criticized, yet it continues to play a significant role in rural drinking water supply. In India, as with other ‘emerging’ economies, the management model must now adapt to meet the policy demand for ever-increasing technical sophistication. Given this context, the paper reviews the history and concepts of community management to propose three typologies that better account for the changing role of the community and external support entities found in successful cases. It argues that external support entities must be prepared to take greater responsibility for providing ongoing support to communities for ensuring continuous service delivery
Large-scale atom probe tomography data mining: methods and application to inform hydrogen behavior
A large number of atom probe tomography (APT) datasets from past experiments were collected into a database to conduct statistical analyses. An effective way of handling the data is shown, and a study on hydrogen is conducted to illustrate the usefulness of this approach. We propose to handle a large collection of APT spectra as a point cloud and use a city block distance-based metric to measure dissimilarity between spectra. This enables quick and automated searching for spectra by similarity. Since spectra from APT experiments on similar materials are similar, the point cloud of spectra contains clusters. Analysis of these clusters of spectra in this point cloud allows us to infer the sample materials. The behavior of contaminant hydrogen is analyzed and correlated with voltage, electric field, and sample base material. Across several materials, the H2+ /H+ ratio is found to decrease with increasing field, likely an indication of postionization of H2+ ions. The absolute amounts of H2+ and H+ are found to frequently increase throughout APT experiments
A 700 year record of Southern Hemisphere extratropical climate variability
Annually dated ice cores from West and East Antarctica provide proxies for past changes in atmospheric circulation over Antarctica and portions of the Southern Ocean, temperature in coastal West and East Antarctica, and the frequency of South Polar penetration of El Niño events. During the period AD 1700–1850, atmospheric circulation over the Antarctic and at least portions of the Southern Hemisphere underwent a mode switch departing from the out-of-phase alternation of multi-decadal long phases of EOF1 and EOF2 modes of the 850 hPa field over the Southern Hemisphere (as defined in the recent record by Thompson and Wallace, 2000; Thompson and Solomon, 2002) that characterizes the remainder of the 700 year long record. From AD 1700 to 1850, lower-tropospheric circulation was replaced by in-phase behavior of the Amundsen Sea Low component of EOF2 and the East Antarctic High component of EOF1. During the first phase of the mode switch, both West and East Antarctic temperatures declined, potentially in response to the increased extent of sea ice surrounding both regions. At the end of the mode switch, West Antarctic coastal temperatures rose and East Antarctic coastal temperatures fell, respectively, to their second highest and lowest of the record. Polar penetration of El Niño events increased during the mode switch. The onset of the AD 1700–1850 mode switch coincides with the extreme state of the Maunder Minimum in solar variability. Late 20th-century West Antarctic coastal temperatures are the highest in the record period, and East Antarctic coastal temperatures close to the lowest. Since AD 1700, extratropical regions of the Southern Hemisphere have experienced significant climate variability coincident with changes in both solar variability and greenhouse gase
Soil health metrics reflect yields in long‑term cropping system experiments
Soil health metrics with strong links to ecological function and agricultural productivity are needed to ensure that future management of agricultural systems meets sustainability goals. While ecological metrics and crop yields are often considered separately from one another, our work sought to assess the links between the two in an agricultural context where productivity is a key consideration. Here, we investigated the value of soil health tests in terms of their relevance to agricultural management practices and crop yields at contrasting long term cropping systems experiments. One site was on a sandy loam Leptic Podzol and the other on a sandy clay loam Endostagnic Luvisol. Furthermore, the experiments had different management systems. One contained legume-supported rotations with different grass-clover ley durations and organic amendment usage, while the other compared a range of nutrient input options through fertiliser and organic amendments on the same rotation without ley periods. Metrics included field tests (earthworm counts and visual evaluation of soil structure scores) with laboratory analysis of soil structure, chemistry and biology. This analysis included bulk density, macroporosity, pH, available phosphorus, exchangeable potassium, soil organic matter and potentially mineralizable nitrogen. Using a novel combination of long-term experiments, management systems and distinctive soil types, we demonstrated that as well as providing nutrients, agricultural management which resulted in better soil organic matter, pH, potassium and bulk density was correlated with higher crop yields. The importance of ley duration and potentially mineralizable nitrogen to yield in legume-supported systems showed the impact of agricultural management on soil biology. In systems with applications of synthetic fertiliser, earthworm counts and visual evaluation of soil structure scores were correlated with higher yields. We concluded that agricultural management altered yields not just through direct supply of nutrients to crops, but also through the changes in soil health measured by simple metrics
Trimellitic anhydride-conjugated serum albumin activates rat alveolar macrophages in vitro
BACKGROUND: Occupational exposure to airborne low molecular weight chemicals, like trimellitic anhydride (TMA), can result in occupational asthma. Alveolar macrophages (AMs) are among the first cells to encounter these inhaled compounds and were previously shown to influence TMA-induced asthma-like symptoms in the Brown Norway rat. TMA is a hapten that will bind to endogenous proteins upon entrance of the body. Therefore, in the present study we determined if TMA and TMA conjugated to serum albumin induced the production of the macrophage mediators nitric oxide (NO), tumour necrosis factor (TNF), and interleukin 6 (IL-6) in vitro using the rat AM cell line NR8383 and primary AMs derived from TMA-sensitized and naïve Brown Norway rats. METHODS: Cells were incubated with different concentrations of TMA, TMA conjugated to bovine serum albumin (BSA), and BSA as a control for 24 h and the culture supernatant was analyzed for mediator content. RESULTS: TMA alone was not able to induce the production of mediators by NR8383 cells and primary AMs from sensitized and sham-treated rats. TMA-BSA, on the contrary, dose-dependently stimulated the production of NO, TNF, and IL-6 by NR8383 cells and of NO and TNF, but not IL-6, by primary AMs independent of sensitization. CONCLUSION: Results suggest that although TMA is a highly reactive compound, conjugation to a suitable protein is necessary to induce mediator production by AMs. Furthermore, the observation that effects of TMA-BSA were independent of sensitization suggests involvement of an immunologically non-specific receptor. In the discussion it is argued that a macrophage scavenger receptor is a likely candidate
Mechanisms of cell entry by human papillomaviruses: an overview
As the primary etiological agents of cervical cancer, human papillomaviruses (HPVs) must deliver their genetic material into the nucleus of the target cell. The viral capsid has evolved to fulfil various roles that are critical to establish viral infection. The particle interacts with the cell surface via interaction of the major capsid protein, L1, with heparan sulfate proteoglycans. Moreover, accumulating evidence suggests the involvement of a secondary receptor and a possible role for the minor capsid protein, L2, in cell surface interactions
- …