771 research outputs found
Ethylene glycol: an estimate of tolerable levels of exposure based on a review of animal and human data
Upon ingestion ethylene glycol (EG, monoethylene glycol) is rapidly absorbed from the gastrointestinal tract, and depending on the severity of exposure signs of toxicity may progress through three stages. Neurological effects characterize the first step consisting of central nervous depression (intoxication, lethargy, seizures, and coma). The second stage, usually 12-24h after ingestion, is characterized by metabolic acidosis due to the accumulation of acidic metabolites of EG, primarily glycolic acid (GA), contributing to the ensuing osmolal and anion gaps. Stage 3, generally 24-72h after ingestion, is determined mainly by oxalic acid excretion, nephropathy, and eventual renal failure. Because the toxicity of EG is mediated principally through its metabolites, adequate analytical methods are essential to provide the information necessary for diagnosis and therapeutic management. The severe metabolic acidosis and multiple organ failure caused by ingestion of high doses of EG is a medical emergency that usually requires immediate measures to support respiration, correct the electrolyte imbalance, and initiate hemodialysis. Since metabolic acidosis is not specific to EG, whenever EG intoxication is suspected, every effort should be made to determine EG as well as its major metabolite GA in plasma to confirm the diagnosis and to institute special treatment without delay. A number of specific and sensitive analytical methods (GC, GC-MS, or HPLC) are available for this purpose. Due to the rapid metabolism of EG, the plasma concentration of GA may be higher than that of EG already upon admission. As toxicity is largely a consequence of metabolism of EG to GA and oxalic acid, the simultaneous quantification of EG and GA is important. Formation of calcium oxalate monohydrate in the urine may be a useful indicator of developing oxalate nephrosis although urine crystals can result without renal injury. The pathways involved in the metabolism of EG are qualitatively similar in humans and laboratory animals, although quantitative differences have been reported. Comparison between species is difficult, however, because the information on humans is derived mainly from acute poisoning cases whereas the effects of repeated exposures have been investigated in animal experiments. Based on published data the minimum human lethal dose of EG has been estimated at approx. 100ml for a 70-kg adult or 1.6g/kg body weight (calculation of dose in ml/kg to mg/kg based in EG density=1.11g/l). However, human data from case reports are generally insufficient for the determination of a clear dose-response relationship and quantification of threshold doses for systemic toxicity, in particular renal effects, is limited. As toxicity is largely a consequence of metabolism of EG to GA, it is important to note that no signs of renal injury have developed at initial plasma glycolate concentrations of up to 10.1mM (76.7mg/dl). Plasma EG levels of 3.2mM (20mg/dl) are considered the threshold of toxicity for systemic exposure, if therapeutic strategy is based on the EG concentration alon
Stereodeficient subjects demonstrate non-linear stereopsis
AbstractThere appear to be two modes of stereoscopic processing: a conventional linear operation that is dependent on correspondence between local luminance components in the two eyesâ views, and a non-linear or second-order processing mode. This second mode may use disparity information provided by particular ânon-Fourierâ features of the stimulus such as the contrast envelope. Preliminary results suggest that people who fail standard clinical stereotests are able to extract non-linear disparity information from Gabor stimuli [McColl & Mitchell, 1998. Vision Research, 38, 1889â1900]. Here we evaluate the status of the non-linear mechanism in such individuals by using two types of contrast enveloped stimuli, namely random line and Gabor micropatterns, in a task that requires near/far depth judgements [Ziegler & Hess, 1999. Vision Research, 39, 1491â1507]. Although our sample was small, three of our four subjects who had performed poorly on at least one standard clinical test of stereopsis could perform the task, as well as one âstereoblindâ subject who had failed all four standard clinical tests. The overall results suggest that individuals with stereoanomalies show a diversity of deficits, but some nevertheless can see depth using ânon-linearâ mechanisms
Turning Points in Relationships with Disliked Co-workers
Although most people begin their employment with the education and on-the-job training to handle the tasks their jobs entail, few long-term employees boast that they feel competent in dealing with all the difficult people they encounter in the workplace. Unpleasant coworkers range from annoying nuisances to major sources of job frustration and career roadblocks. Given that periodic preoccupation with unlovable coworkers is nearly a universal feature of organizational life, it is not surprising that such relationships are given due attention in the media and popular press (e.g., Bramson, 1989; Topchik, 2000). What is surprising is how little scholarly attention has been given to such interactions. Scholars have extensively examined the outcomes of positive work relationships, such as social support and friendship through co-worker relationships and guidance through mentoring (e.g., Bridge & Baxter, 1992; Kram & Isabella, 1985). However, only recently has scholarly attention been focused on identifying troublesome coworkers and documenting outcomes of unpleasant work relationships such as cynicism and reduced job satisfaction and organizational commitment (e.g., Fritz, 2002; Omdahl & Fritz, 2000). This neglect of unpleasant or difficult relationships in the workplace mirrors the more general literature on interpersonal communication. For decades, the focus has been on the development and maintenance of effective relationships, and only recently has research on the âdark sideâ of personal relationships gained attention (Duck, 1994).
This examination of negative relationships in general and with negative coworkers in particular is long overdue. People spend considerable time and energy navigating difficult relationships, and many working hours are spent in the company of others whom we do not voluntarily seek out and may actively dislike (Hess, 2000). These relationships have many negative effects on employees and organizations. For instance, research has shown that negative relationships detract from a personâs occupational experience through increased stress, workplace cynicism, organizational turnover, and decreased job satisfaction, organizational commitment, and task effectiveness (e.g., Cooper & Cartwright, 1994; Fritz & Omdahl, 1998). Research that increases scholarsâ understanding of the causes, nature, and processes of such relationships can offer insight for communication theory and practice
The Impact of Consumer Product Package Quality on Consumption Satisfaction, Brand Perceptions, Consumer Investment and Behavior
Consumer product packaging can serve a critical role in the consumption experience, but marketing and packaging science researchers focus primarily on pre and post-consumption aspects of consumer product containers. Exhaustive research into packing ergonomics, logistics, safety, sustainability and promotional features are common across marketing and packaging disciplines, but research isolating the role of a packaging in consumption satisfaction and enduring consumer-brand relationships is rare. In addition to an undervalued role in product satisfaction, functional isolation between marketing and packaging scientists limits packagingâs overall impact on the bottom line.
This research examines the role of bottle quality in bottled-water consumption satisfaction and its subsequent impact on brand attribute perceptions, consumer-brand relationship investment and behavioral intentions. We show that thicker water bottles are perceived to be of higher quality than thinner bottles, and that these perceptual differences impact how customers view a brand on aspects such as reliability and value offered by the brandâs products and ultimately intentions to re-purchase the brandâs products.
We use qualitative, experimental and structural modeling analysis techniques to establish a fundamental role of packaging quality in consumer product satisfaction. We show that packaging characteristics are an indivisible component of the product and important to evaluation of the overall consumption experience. We finally conclude that packaging quality has a critical role to play in building profitable consumer-brand relationships, which should redefine the packaging cost-benefit equation to include the value of consumer loyalty as a balance to non-consumption packaging considerations
Effects of eHealth Literacy on General Practitioner Consultations: A Mediation Analysis.
BackgroundMost evidence (not all) points in the direction that individuals with a higher level of health literacy will less frequently utilize the health care system than individuals with lower levels of health literacy. The underlying reasons of this effect are largely unclear, though people's ability to seek health information independently at the time of wide availability of such information on the Internet has been cited in this context.ObjectiveWe propose and test two potential mediators of the negative effect of eHealth literacy on health care utilization: (1) health information seeking and (2) gain in empowerment by information seeking.MethodsData were collected in New Zealand, the United Kingdom, and the United States using a Web-based survey administered by a company specialized on providing online panels. Combined, the three samples resulted in a total of 996 baby boomers born between 1946 and 1965 who had used the Internet to search for and share health information in the previous 6 months. Measured variables include eHealth literacy, Internet health information seeking, the self-perceived gain in empowerment by that information, and the number of consultations with one's general practitioner (GP). Path analysis was employed for data analysis.ResultsWe found a bundle of indirect effect paths showing a positive relationship between health literacy and health care utilization: via health information seeking (Path 1), via gain in empowerment (Path 2), and via both (Path 3). In addition to the emergence of these indirect effects, the direct effect of health literacy on health care utilization disappeared.ConclusionsThe indirect paths from health literacy via information seeking and empowerment to GP consultations can be interpreted as a dynamic process and an expression of the ability to find, process, and understand relevant information when that is necessary
Mechanism of activation of Agrobacterium virulence genes: identification of phenol-binding proteins.
Colossal Magnetoresistance is a Griffiths Singularity
It is now widely accepted that the magnetic transition in doped manganites
that show large magnetoresistance is a type of percolation effect. This paper
demonstrates that the transition should be viewed in the context of the
Griffiths phase that arises when disorder suppresses a magnetic transition.
This approach explains unusual aspects of susceptibility and heat capacity data
from a single crystal of LaCaMnOComment: 4 page
Tunneling spectroscopy in the magnetic superconductor TmNi2B2C
We present new measurements about the tunneling conductance in the
borocarbide superconductor TmNiBC. The results show a very good
agreement with weak coupling BCS theory, without any lifetime broadening
parameter, over the whole sample surface. We detect no particular change of the
tunneling spectroscopy below 1.5K, when both the antiferromagnetic (AF) phase
and the superconducting order coexist.Comment: Submitted to Phys. Rev. B, Rapid Communication
Exploring Spirituality in Teaching Within a Christian School Context Through Collaborative Action Research
This article reports on a collaborative action research project conducted in New Zealand, during 2012, exploring spirituality in teaching within a Christian school context. The experienced primary school teacher participant chose to take action around the issue of personal fear and insecurity which were believed to be hindering professional growth and relationships. Through self-directed inquiry, critical reflective journaling, Bible study, fellowship and prayer with trusted friends, the teacher experienced a renewed sense of peace and freedom in Christ. This personal transformation was believed to be influential on subsequent professional practice, assisting the teacher to become more relational, responsive and compassionate. The findings provide a rich description of the participantâs spirituality, the lived reality of a personâs spiritual life. This report will be of interest to teachers, teacher-leaders and teacher-educators who desire to explore Christian spirituality through practitioner-led inquiry
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