3,778 research outputs found
Modern Professionals and Their Tools ICT Supporting Organizational Flexibility and Control
The modern organisation can be characterised in terms of the continuous struggle between providing organisational flexibility and control. Organisational flexibility and informality support the members in facilitating, mentoring, innovating and brokering. Organisational control serves the purpose of coordinating, monitoring, directing and producing. The aim of this paper is to study how modern professionals manage their use of multiple Information and Communication Technologies (ICT) in the context of the requirements for organisational flexibility and control. This is accomplished through interviews with 16 modern professionals reflecting upon their use of ICT. The study firstly demonstrates that the multiplicity of ICT possibilities require of the modern professional to reflect upon the technologies they adopt and the specific ways in which they apply the technologies. We also clearly saw both the importance of some technologies, such as email and the unimportance of others, in particular the PDA. Generally, the study demonstrated the importance of flexible and informal ICT, even for the performance of work required to maintain organisational control
Investigating Composite Action at Ultimate for Commercial Sandwich Panel Composite Connectors
To achieve full or partial-composite action in prestressed concrete sandwich panel walls, the engineer must obtain a percent composite action from a connector manufacturer, making some engineers uncomfortable. Engineers are dependent upon the recommendations given by the connector manufacturers to establish their designs. This project tested six full-scale sandwich panel walls to evaluate the percent composite action of various connectors and compare the results to those provided by the composite connector manufacturers. This study concluded that the reported degrees of composite action from each manufacturer are considered conservative in all instances for the connectors tested in this paper. Additionally, the intensity and type of connectors are important factors in determining the degree of partial composite action in a panel
Percent Composite Action at Ultimate in Sandwich Wall Panel Connectors
Many engineers feel uncomfortable that they must currently rely on percent-of-composite-action values obtained from a connector manufacturer to achieve full or partial-composite action in prestressed concrete sandwich wall panels. Engineers are dependent upon these recommendations to establish their designs. This project tested six full-scale concrete sandwich wall panels to evaluate the percent composite action of various connectors. These resulting values were then compared to those provided by the composite connector manufacturers. This study concluded that the reported degrees of composite action from each manufacturer are considered conservative in all instances for the connectors tested in this study. Additionally, the intensity and type of connectors are important factors to be considered in determining the degree of partial composite action in a panel
Developing a General Methodology for Evaluating Composite Action in Insulated Wall Panels
Precast concrete sandwich wall panels(PCSWPs) have been in use for over 60 years. They provide a very efficient building envelope for many buildings. Characteristic PCSWPs comprise an outer and inner layer (or wythe) of concrete separated by an insulating material. To use all of the material as efficiently as possible, the layers are attached by connectors which penetrate through the insulating layer and are embedded in either concrete wythe. These connectors make it possible for both layers of the wall to work together when resisting loads. The connectors are made out of plastic, or FRP, to prevent heat transfer from one side of the wall to the other.
This research evaluated several different FRP systems by fabricating and testing 41small scale āpush-offā specimens (3 ft. by 4 ft., 0.91 m by 1.22 m)and eight full-scale sandwich panel walls to evaluate the percent composite action of various connectors and compare the results to those provided by the composite connector manufacturers. Testing of push-off specimens was performed by applying loads perpendicular to the connectors and measuring the amount of deformation that occurred. By determining the load-deformation relationship, engineers can make more informed decisions about the full-scale behavior. This project aimed to validate current procedures using these methods, and to develop simpler, more efficient methods for predicting overall strength of this innovative building system. This study concluded that the reported degrees of composite action from each manufacturer are considered conservative in all instances for the connectors tested. Additionally, the intensity and type of connectors are important factors in determining the degree of partial composite action in a panel.
Two methods to predict elastic deformations and cracking were developed(the Beam-Spring model and the Elastic Hand Method) and were compared to the elastic portions of the full-scale testing performed in this study, yielding promising results. Anew method(thePartially-Composite Strength Prediction Method) was also created to predict the nominal moment capacity of concrete sandwich wall panels that is easier to implement than current methodologies and shown to be accurate. The results of this method were also compared to the full-scale testing results in this study.Design and analysis examples using these methods are presented in this report.(243pages
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Overdose rescues by trained and untrained participants and change in opioid use among substance-using participants in overdose education and naloxone distribution programs: a retrospective cohort study
Background: One approach to preventing opioid overdose, a leading cause of premature, preventable mortality, is to provide overdose education and naloxone distribution (OEND). Two outstanding issues for OEND implementation include 1) the dissemination of OEND training from trained to untrained community members; and 2) the concern that OEND provides active substance users with a false sense of security resulting in increased opioid use. Methods: To compare overdose rescue behaviors between trained and untrained rescuers among people reporting naloxone rescue kit use; and determine whether heroin use changed after OEND, we conducted a retrospective cohort study among substance users in the Massachusetts OEND program from 2006 to 2010. We used chi square and t-test statistics to compare the differences in overdose management characteristics among overdoses managed by trained versus untrained participants. We employed Wilcoxon signed rank test to compare median difference among two repeated measures of substance use among participants with drug use information collected more than once. Results: Among 4,926 substance-using participants, 295 trained and 78 untrained participants reported one or more rescues, resulting in 599 rescue reports. We found no statistically significant differences in help-seeking (p = 0.41), rescue breathing (p = 0.54), staying with the victim (p = 0.84) or in the success of naloxone administration (p = 0.69) by trained versus untrained rescuers. We identified 325 OEND participants who had drug use information collected more than once. We found no significant overall change in the number of days using heroin in past 30 days (decreased 38%, increased 35%, did not change 27%, p = 0.52). Conclusion: Among 4926 substance users who participated in OEND, 373(7.6%) reported administering naloxone during an overdose rescue. We found few differences in behavior between trained and untrained overdose rescuers. Prospective studies will be needed to determine the optimal level of training and whether naloxone rescue kits can meet an over-the-counter standard. With no clear evidence of increased heroin use, this concern should not impede expansion of OEND programs or policies that support them
Wear of polycrystalline boron nitride tool during the friction stir welding of steel
The wear issue of a polycrystalline boron nitride (PCBN) tools during the friction stir welding of two grades of steel, DH36 and EH46, was studied. Two welding traverse and tool rotational speeds were used when welding the DH36 steel. A low tool speed (200RPM, 100 mm/min) and a high tool speed (550RPM, 400 mm/min) were denoted by W1D and W2D, respectively. Nine welding conditions were applied to the welding of EH46 steel plate including seven plunge/dwell trials (W1EāW7E) and two steady-state trials (W8E and W9E). SEMāEDS and XRD tests were applied in order to reveal the boronitride (BN) particles inside the welded joints, and the percentage (%) of BN was calculated according to the standard quantitative metallographic technique. The findings showed that tool wear increases when the tool rotational speed increases as a result of binder softening which is a function of the peak temperature (exceeds 1250 Ā°C) at the tool/workpiece interface. When considering the EH46 steel trials, it was found that an increase in the tool traverse speed in friction stir welding caused a significant tool wear with 4.4% of BN in the top of the stirred zone of W9E compared to 1.1% volume fraction of BN in W8E which was attributed to the higher thermomechanical action on the PCBN tool surface. Tool wear was also found to increase with an increase in tool plunge depth as a result of the higher contact between the surface of friction stir welding tool and the workpiece
dAtaxin-2 Mediates Expanded Ataxin-1-Induced Neurodegeneration in a Drosophila Model of SCA1
Spinocerebellar ataxias (SCAs) are a genetically heterogeneous group of neurodegenerative disorders sharing atrophy of the cerebellum as a common feature. SCA1 and SCA2 are two ataxias caused by expansion of polyglutamine tracts in Ataxin-1 (ATXN1) and Ataxin-2 (ATXN2), respectively, two proteins that are otherwise unrelated. Here, we use a Drosophila model of SCA1 to unveil molecular mechanisms linking Ataxin-1 with Ataxin-2 during SCA1 pathogenesis. We show that wild-type Drosophila Ataxin-2 (dAtx2) is a major genetic modifier of human expanded Ataxin-1 (Ataxin-1[82Q]) toxicity. Increased dAtx2 levels enhance, and more importantly, decreased dAtx2 levels suppress Ataxin-1[82Q]-induced neurodegeneration, thereby ruling out a pathogenic mechanism by depletion of dAtx2. Although Ataxin-2 is normally cytoplasmic and Ataxin-1 nuclear, we show that both dAtx2 and hAtaxin-2 physically interact with Ataxin-1. Furthermore, we show that expanded Ataxin-1 induces intranuclear accumulation of dAtx2/hAtaxin-2 in both Drosophila and SCA1 postmortem neurons. These observations suggest that nuclear accumulation of Ataxin-2 contributes to expanded Ataxin-1-induced toxicity. We tested this hypothesis engineering dAtx2 transgenes with nuclear localization signal (NLS) and nuclear export signal (NES). We find that NLS-dAtx2, but not NES-dAtx2, mimics the neurodegenerative phenotypes caused by Ataxin-1[82Q], including repression of the proneural factor Senseless. Altogether, these findings reveal a previously unknown functional link between neurodegenerative disorders with common clinical features but different etiology
Gender-specific associations of serum sex hormone-binding globulin with features of metabolic syndrome in children
Prioritisation of pharmaceuticals based on risks to aquatic environments in Kazakhstan
Over the last 20 years, there has been increasing interest in the occurrence, fate, effects and risk of pharmaceuticals in the natural environment. However, we still have only limited or no data on ecotoxicological risks of many of the active pharmaceutical ingredients (APIs) currently in use. This is partly due to the fact that the environmental assessment of an API is an expensive, time-consuming and complicated process. Prioritisation methodologies, that aim to identify APIs of most concern in a particular situation, could therefore be invaluable in focusing experimental work on APIs that really matter. The majority of approaches for prioritising APIs require annual pharmaceutical usage data. These methods cannot therefore be applied to countries, such as Kazakhstan, which have very limited data on API usage. This paper therefore presents an approach for prioritising APIs in surface waters in information-poor regions such as Kazakhstan. Initially data were collected on the number of products and active ingredients for different therapeutic classes in use in Kazakhstan and on the typical doses. These data were then used alongside simple exposure modelling approaches to estimate exposure indices for active ingredients (about 240 APIs) in surface waters in the country. Ecotoxicological effects data were obtained from the literature or predicted. Risk quotients were then calculated for each pharmaceutical based on the exposure and the substances ranked in order of risk quotient. Highest exposure indices were obtained for benzylpenicillin, metronidazole, sulbactam, ceftriaxone and sulfamethoxazole. The highest risk was estimated for amoxicillin, clarithromycin, azithromycin, ketoconazole and benzylpenicillin. In the future, the approach could be employed in other regions where usage information are limited. This article is protected by copyright. All rights reserved
Single-sex schistosome infections of definitive hosts: Implications for epidemiology and disease control in a changing world
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