The structure of the asteroid 4 Vesta as revealed by models of planet-scale collisions

Asteroid 4Vesta seems to be a major intact protoplanet, with a surface composition similar to that of the HED (howardite-eucrite-diogenite) meteorites. The southern hemisphere is dominated by a giant impact scar, but previous impact models have failed to reproduce the observed topography. The recent discovery that Vesta's southern hemisphere is dominated by two overlapping basins provides an opportunity to model Vesta's topography more accurately. Here we report three-dimensional simulations of Vesta's global evolution under two overlapping planet-scale collisions. We closely reproduce its observed shape, and provide maps of impact excavation and ejecta deposition. Spiral patterns observed in the younger basin Rheasilvia, about one billion years old, are attributed to Coriolis forces during crater collapse. Surface materials exposed in the north come from a depth of about 20kilometres, according to our models, whereas materials exposed inside the southern double-excavation come from depths of about 60-100kilometres. If Vesta began as a layered, completely differentiated protoplanet, then our model predicts large areas of pure diogenites and olivine-rich rocks. These are not seen, possibly implying that the outer 100kilometres or so of Vesta is composed mainly of a basaltic crust (eucrites) with ultramafic intrusions (diogenites).

THE EXPRESSION AND CELLULAR LOCALIZATION OF CC-CHEMOKINE RECEPTOR 5 (CCR5) AFTER TRAUMATIC BRAIN INJURY

Traumatic brain injury results from a primary insult and secondary events that together result in tissue injury. This primary injury occurs at the moment of impact and damage can include scalp laceration, skull fraction, cerebral contusions and lacerations as well as intracranial hemorrhage. Following the initial insult, a delayed response occurs and is characterized by hypoxia, ischemia, cerebral edema, and infection. During secondary brain injury, a series of neuroinflammatory events are triggered that can produce additional damage but may also help to protect nervous tissue from invading pathogens and help to repair the damaged tissue. Brain microglia and astrocytes become activated and migrate to the site of injury where these cells secrete immune mediators such as cytokines and chemokines. CC-chemokine receptor 5 (CCR5) is a member of the CC chemokine receptor family of seven transmembrane G protein coupled receptors. CCR5 is expressed in the immune system and is found in monocytes, leukoctyes, memory T cells, and immature dendritic cells. Upon binding to its ligands, CCR5 functions in the chemotaxis of these immune cells to the site of inflammation. In the CNS, CCR5 and its ligands are expressed in multiple cell types. In this study, I investigated whether CCR5 expression is altered in brain after traumatic brain injury. I examined the time course of CCR5 protein expression in cortex and hippocampus using quantitative western analysis of tissues from injured rat brain after mild impact injury. In addition, I also investigated the cellular localization of CCR5 before and after brain injury using confocal microscopy. I have observed that after brain injury CCR5 is upregulated in a time dependent manner in neurons of the parietal cortex and hippocampus. The absence of CCR5 expression in microglia and its delayed expression in neurons after injury suggests a role for CCR5 in neuronal survival after injury.

THE EXPRESSION AND CELLULAR LOCALIZATION OF CC-CHEMOKINE RECEPTOR 5 (CCR5) AFTER TRAUMATIC BRAIN INJURY

Traumatic brain injury results from a primary insult and secondary events that together result in tissue injury. This primary injury occurs at the moment of impact and damage can include scalp laceration, skull fraction, cerebral contusions and lacerations as well as intracranial hemorrhage. Following the initial insult, a delayed response occurs and is characterized by hypoxia, ischemia, cerebral edema, and infection. During secondary brain injury, a series of neuroinflammatory events are triggered that can produce additional damage but may also help to protect nervous tissue from invading pathogens and help to repair the damaged tissue. Brain microglia and astrocytes become activated and migrate to the site of injury where these cells secrete immune mediators such as cytokines and chemokines. CC-chemokine receptor 5 (CCR5) is a member of the CC chemokine receptor family of seven transmembrane G protein coupled receptors. CCR5 is expressed in the immune system and is found in monocytes, leukoctyes, memory T cells, and immature dendritic cells. Upon binding to its ligands, CCR5 functions in the chemotaxis of these immune cells to the site of inflammation. In the CNS, CCR5 and its ligands are expressed in multiple cell types. In this study, I investigated whether CCR5 expression is altered in brain after traumatic brain injury. I examined the time course of CCR5 protein expression in cortex and hippocampus using quantitative western analysis of tissues from injured rat brain after mild impact injury. In addition, I also investigated the cellular localization of CCR5 before and after brain injury using confocal microscopy. I have observed that after brain injury CCR5 is upregulated in a time dependent manner in neurons of the parietal cortex and hippocampus. The absence of CCR5 expression in microglia and its delayed expression in neurons after injury suggests a role for CCR5 in neuronal survival after injury.

Towards a Hybrid Method to Categorize Interruptions and Activities in Healthcare

Objective Interruptions are known to have a negative impact on activity performance. Understanding how an interruption contributes to human error is limited because there is not a standard method for analyzing and classifying interruptions. Qualitative data are typically analyzed by either a deductive or an inductive method. Both methods have limitations. In this paper a hybrid method was developed that integrates deductive and inductive methods for the categorization of activities and interruptions recorded during an ethnographic study of physicians and registered nurses in a Level One Trauma Center. Understanding the effects of interruptions is important for designing and evaluating informatics tools in particular and for improving healthcare quality and patient safety in general. Method The hybrid method was developed using a deductive a priori classification framework with the provision of adding new categories discovered inductively in the data. The inductive process utilized line-by-line coding and constant comparison as stated in Grounded Theory. Results The categories of activities and interruptions were organized into a three-tiered hierarchy of activity. Validity and reliability of the categories were tested by categorizing a medical error case external to the study. No new categories of interruptions were identified during analysis of the medical error case. Conclusions Findings from this study provide evidence that the hybrid model of categorization is more complete than either a deductive or an inductive method alone. The hybrid method developed in this study provides the methodical support for understanding, analyzing, and managing interruptions and workflow.

Towards a hybrid method to categorize interruptions and activities in healthcare.

OBJECTIVE: Interruptions are known to have a negative impact on activity performance. Understanding how an interruption contributes to human error is limited because there is not a standard method for analyzing and classifying interruptions. Qualitative data are typically analyzed by either a deductive or an inductive method. Both methods have limitations. In this paper, a hybrid method was developed that integrates deductive and inductive methods for the categorization of activities and interruptions recorded during an ethnographic study of physicians and registered nurses in a Level One Trauma Center. Understanding the effects of interruptions is important for designing and evaluating informatics tools in particular as well as improving healthcare quality and patient safety in general. METHOD: The hybrid method was developed using a deductive a priori classification framework with the provision of adding new categories discovered inductively in the data. The inductive process utilized line-by-line coding and constant comparison as stated in Grounded Theory. RESULTS: The categories of activities and interruptions were organized into a three-tiered hierarchy of activity. Validity and reliability of the categories were tested by categorizing a medical error case external to the study. No new categories of interruptions were identified during analysis of the medical error case. CONCLUSIONS: Findings from this study provide evidence that the hybrid model of categorization is more complete than either a deductive or an inductive method alone. The hybrid method developed in this study provides the methodical support for understanding, analyzing, and managing interruptions and workflow.

5-HT and GABA modulate intrinsic excitability of type I interneurons in Hermissenda.

The sensory neurons (photoreceptors) in the visual system of Hermissenda are one site of plasticity produced by Pavlovian conditioning. A second site of plasticity produced by conditioning is the type I interneurons in the cerebropleural ganglia. Both photoreceptors and statocyst hair cells of the graviceptive system form monosynaptic connections with identified type I interneurons. Two proposed neurotransmitters in the graviceptive system, serotonin (5-HT) and gamma-aminobutyric acid (GABA), have been shown to modify synaptic strength and intrinsic neuronal excitability in identified photoreceptors. However, the potential role of 5-HT and GABA in plasticity of type I interneurons has not been investigated. Here we show that 5-HT increased the peak amplitude of light-evoked complex excitatory postsynaptic potentials (EPSPs), enhanced intrinsic excitability, and increased spike activity of identified type I(e(A)) interneurons. In contrast, 5-HT decreased spike activity and intrinsic excitability of type I(e(B)) interneurons. The classification of two categories of type I(e) interneurons was also supported by the observation that 5-HT produced opposite effects on whole cell steady-state outward currents in type I(e) interneurons. Serotonin produced a reduction in the amplitude of light-evoked complex inhibitory PSPs (IPSPs), increased spontaneous spike activity, decreased intrinsic excitability, and depolarized the resting membrane potential of identified type I(i) interneurons. In contrast to the effects of 5-HT, GABA produced inhibition in both types of I(e) interneurons and type I(i) interneurons. These results show that 5-HT and GABA can modulate the intrinsic excitability of type I interneurons independent of the presynaptic effects of the same transmitters on excitability and synaptic efficacy of photoreceptors.

The epidemiology of chronic fatigue in San Francisco

Chronic fatigue syndrome (CFS) is a recently defined condition characterized by severe disabling fatigue that persists for a minimum of six months, and a host of somatic and neurocognitive symptoms. Although conditions similar to CFS have been described in the medical literature for over 100 years, little is known about the epidemiology of CFS or of chronic fatigue generally. The San Francisco Fatigue Study was undertaken to describe the prevalence and characteristics of self-reported chronic fatigue and associated conditions in a diverse urban community. The study utilized a cross-sectional telephone survey of a random sample of households in San Francisco, followed by case/control interviews of fatigued and nonfatigued subjects. Respondents were classified as chronically fatigued (CF) if they reported severe fatigue lasting six months or longer, then further classified as having CFS-like illness if, based on self-reported information, their condition appeared to meet CFS case definition criteria. Subjects who reported idiopathic chronic fatigue that did not meet CFS criteria were classified as having ICF-like illness.^ 8004 households were screened, yielding fatigue and demographic information on 16970 residents. CF was reported by 635 persons, 3.7% of the study population. CFS-like illness was identified in 34 subjects (0.2%), and ICF-like illness in 259 subjects (1.6%). Logistic regression analysis indicated that prevalence odds ratios for CFS-like illness were significantly elevated for females compared to males (OR = 2.9), and in Blacks (OR = 2.9) and Native Americans (OR = 13.2) relative to Whites, but significantly lower in Asians (OR = 0.12). Above-average household income was protective for all categories of CF. CFS-like subjects reported more symptoms and were more severely disabled than ICF-like subjects, but the pattern of symptoms experienced by both groups was similar. In conclusion, unexplained chronic fatigue, including CFS-like illness, occurs in all sociodemographic groups, but may be most prevalent among persons with lower incomes and in some racial minorities. Future studies that include clinical evaluation of incident cases of CFS and ICF are required to further clarify the epidemiology of unexplained chronic fatigue in the population. ^

The prevalence of burnout among psychologists and psychological associates in the state of Texas

This study investigates the prevalence of burnout among a sample of Texas psychologists and psychological associates as well as differences between the three categories of practitioners within that group (Licensed Psychology Health Care Providers (LPHCP), Licensed Psychologists - Certified Psychologists (LP-CP), Psychological Associates (PA)).^ The Maslach Burnout Inventory and a questionnaire seeking demographic information was used in this cross-sectional survey. Sample size was 654. A stratified proportionate random sample of Texas Psychologists was drawn. The response rate based on usable returns was 55% (n = 359). General demographic characteristics were determined mainly by frequency distributions. For comparing means of samples, t and multiple range tests were used. A series of one-way and two-way analysis of variance procedures were used to compare subgroup differences in burnout.^ The universe was representative for the sample and for the three categories of psychologists. Urban subjects were more likely to respond, as were male PAs. Practitioners were as likely male as female, working in an urban area, in their present job eight years, and in the occupation for fifteen. The LPHCP group were older, had been in psychology and at their present job longer, and were more likely to belong to both state and local professional organizations than the other two groups. Males outnumbered females in this group and in LP-CPs. This gender trend was reversed for PAs. Of the total sample, 76% reported high job satisfaction and 77% had high levels of perceived job autonomy. There was no significant difference between the study sample and the mental health norms in emotional exhaustion (EE). Our sample had significantly less feelings of depersonalization (DP) and higher feelings of personal accomplishment (PA). Psychological Associates felt significantly less personal accomplishment than the other groups. Predictors for the total sample indicated younger practitioners and those with low job satisfaction had significantly higher burnout, as did males when compared to their female cohorts. Some types of jobs were more likely to contribute to burnout than others. Membership in their local area professional organization lessened the chances for burnout significantly. Predictors for categories of psychologists indicated that males in the LPHCP and LP-CP groups were at higher risk than females. Further, for LP-CPs low job satisfaction and job autonomy, as well as job sites, were significant. Those in this group who worked as school psychologists were at the highest risk for burnout. Job dissatisfaction was the major predictor of burnout for psychological associates. Practitioners working in state or government agencies, school systems and administrative jobs generally had higher burnout than those on a university faculty or in private practice. (Abstract shortened by UMI.) ^

The Emergence of Partnership Networks in the Enterprise Application Development Industry - A Global Corporation Perspective

Currently, dramatic changes are happening in the IS development industry. The incumbent system developers (hubs) are embracing partnerships with less well established companies (spokes), acting in specific niches. This paper seeks to establish a better understanding of the motives for this strategy. Relying on existing work on strategic alliance formation, it is argued that partnering is particularly attractive, if these small companies possess certain capabilities that are difficult to obtain through other arrangements than partnering. Again drawing on the literature, three categories of capabilities are identified: the capability to innovate within their niche, the capability to provide a specific functionality that can be integrated with the incumbents’ systems, and the capability to address novel markets. These factors are analyzed through a case study. The case represents a market leader in the global IS development industry, which fosters a network of smaller partner firms. The study reveals that temporal dynamics between the identified factors are playing a dominant role in these networks. A cyclical partnership model is developed that attempts to explain the life cycle of a partnership within such a network.

[The effectiveness of rare earth elements as a possible alternative growth promoter for pigs and poultry].

Mixtures of Rare Earth Elements (REE) have been used as animal growth-promoters on a large scale in China during the last 20 years. Numerous studies carried out in China claim it produces quite sensational growth-promoting effects in all categories of farm animals. To explore the question of whether REE's might prove suitable as a growth-promoter under western keeping conditions, feeding experiments were performed on pigs and poultry. The animals received a typical diet, supplemented with REE salts in concentrations between 75 and 300 mg/kg feed. Weight-gain, feed-intake, feed-conversion and (where applicable) laying parameters were observed. It was shown that in pigs receiving feed supplemented with REEs, an increase in daily weight gain of up to 19% and an improvement in feed-conversion of up to 11% can be achieved, whereas, for poultry, no positive effects on growth or productivity of the animals could be observed. Testing of important organs via Neutron Activating Analysis (NAA) showed a minute accumulation of REE, principally in liver and bones. Analysis of the poultry gut-flora, using selective media, showed that the main microorganism populations of the alimentary canal were unaffected by feed-supplementation with REE.

What drives adult personality development? A comparison of theoretical perspectives and empirical evidence

Increasing numbers of empirical studies provide compelling evidence that personality traits change across the entire lifespan. What initiates this continuing personality development and how does this development proceed? In this paper, we compare six theoretical perspectives that offer testable predictions about why personality develops the way it does and identify limitations and potentials of these perspectives by reviewing how they hold up against the empirical evidence. While all of these perspectives have received some empirical support, there is only little direct evidence for propositions put forward by the five-factor theory of personality and the theory of genotype→environment effects. In contrast, the neo-socioanalytic theory appears to offer a comprehensive framework that fits the empirical findings and allows the integration of other, more specialized, perspectives that focus on specific aspects of personality development like the role of time, systematic differences between categories of social roles or the active partake of the person himself or herself. We draw conclusions on the likely driving factors for adult personality development and identify avenues for future research.

Derivation and validation of multimarker prognostication for normotensive patients with acute symptomatic pulmonary embolism.

RATIONALE Not all patients with acute pulmonary embolism (PE) have a high risk of an adverse short-term outcome. OBJECTIVES This prospective cohort study aimed to develop a multimarker prognostic model that accurately classifies normotensive patients with PE into low and high categories of risk of adverse medical outcomes. METHODS The study enrolled 848 outpatients from the PROTECT (PROgnosTic valuE of Computed Tomography) study (derivation cohort) and 529 patients from the Prognostic Factors for Pulmonary Embolism (PREP) study (validation cohort). Investigators assessed study participants for a 30-day complicated course, defined as death from any cause, hemodynamic collapse, and/or adjudicated recurrent PE. MEASUREMENTS AND MAIN RESULTS A complicated course occurred in 63 (7.4%) of the 848 normotensive patients with acute symptomatic PE in the derivation cohort and in 24 patients (4.5%) in the validation cohort. The final model included the simplified Pulmonary Embolism Severity Index, cardiac troponin I, brain natriuretic peptide, and lower limb ultrasound testing. The model performed similarly in the derivation (c-index of 0.75) and validation (c-index of 0.85) cohorts. The combination of the simplified Pulmonary Embolism Severity Index and brain natriuretic peptide testing showed a negative predictive value for a complicated course of 99.1 and 100% in the derivation and validation cohorts, respectively. The combination of all modalities had a positive predictive value for the prediction of a complicated course of 25.8% in the derivation cohort and 21.2% in the validation cohort. CONCLUSIONS For normotensive patients who have acute PE, we derived and validated a multimarker model that predicts all-cause mortality, hemodynamic collapse, and/or recurrent PE within the following 30 days.

Copeptin for the prediction of recurrent cerebrovascular events after transient ischemic attack: results from the CoRisk study.

BACKGROUND AND PURPOSE Copeptin has been associated with recurrent cerebrovascular events after transient ischemic attack (TIA). In an independent cohort, we evaluated copeptin for the prediction of recurrent cerebrovascular events within 3 months after TIA and assessed the incremental value of copeptin compared with the ABCD2 (age, blood, clinical features of TIA, duration of symptoms, presence of diabetes mellitus) and ABCD3-I (ABCD2, dual TIA [the presence of ≥2 TIA symptoms within 7 days], imaging [the presence of abnormal findings on neuroimaging]) scores. METHODS This prospective, multicenter cohort study was conducted at 3 tertiary Stroke Centers in Switzerland and Germany. RESULTS From March 2009 through April 2011, we included 302 patients with TIA admitted within 24 hours from symptom onset. Of 28 patients with a recurrent cerebrovascular event within 3 months (stroke or TIA), 11 patients had a stroke. Although the association of copeptin with recurrent cerebrovascular events was not significant, the association with stroke alone as end point was significant. After adjusting for the ABCD2 score, a 10-fold increase in copeptin levels was associated with an odds ratio for stroke of 3.39 (95% confidence interval, 1.28-8.96; P=0.01). After addition of copeptin to the ABCD2 score, the area under the curve of the ABCD2 score improved from 0.60 (95% confidence interval, 0.46-0.74) to 0.74 (95% confidence interval, 0.60-0.88, P=0.02). In patients with MRI (n=223), the area under the curve of the ABCD3-I score increased in similar magnitude, although not significantly. Based on copeptin, 31.2% of patients were correctly reclassified across the risk categories of the ABCD2 score (net reclassification improvement; P=0.17). CONCLUSIONS Copeptin improved the prognostic value of the ABCD2 score for the prediction of stroke but not TIA, and it may help clinicians in refining risk stratification for patients with TIA. CLINICAL TRIAL REGISTRATION URL http://www.clinicaltrials.gov. Unique identifier: NCT00878813.

Appropriateness and long-term discontinuation rate of biological therapies in ulcerative colitis

BACKGROUND Anti-TNFα agents are commonly used for ulcerative colitis (UC) therapy in the event of non-response to conventional strategies or as colon-salvaging therapy. The objectives were to assess the appropriateness of biological therapies for UC patients and to study treatment discontinuation over time, according to appropriateness of treatment, as a measure of outcome. METHODS We selected adult ulcerative colitis patients from the Swiss IBD cohort who had been treated with anti-TNFα agents. Appropriateness of the first-line anti-TNFα treatment was assessed using detailed criteria developed during the European Panel on the Appropriateness of Therapy for UC. Treatment discontinuation as an outcome was assessed for categories of appropriateness. RESULTS Appropriateness of the first-line biological treatment was determined in 186 UC patients. For 64% of them, this treatment was considered appropriate. During follow-up, 37% of all patients discontinued biological treatment, 17% specifically because of failure. Time-to-failure of treatment was significantly different among patients on an appropriate biological treatment compared to those for whom the treatment was considered not appropriate (p=0.0007). Discontinuation rate after 2years was 26% compared to 54% between those two groups. Patients on inappropriate biological treatment were more likely to have severe disease, concomitant steroids and/or immunomodulators. They were also consistently more likely to suffer a failure of efficacy and to stop therapy during follow-up. CONCLUSION Appropriateness of first-line anti-TNFα therapy results in a greater likelihood of continuing with the therapy. In situations where biological treatment is uncertain or inappropriate, physicians should consider other options instead of prescribing anti-TNFα agents.

Evaluation of Swiss slaughterhouse data for integration in a syndromic surveillance system

BACKGROUND: We evaluated Swiss slaughterhouse data for integration in a national syndromic surveillance system for the early detection of emerging diseases in production animals. We analysed meat inspection data for cattle, pigs and small ruminants slaughtered between 2007 and 2012 (including emergency slaughters of sick/injured animals); investigating patterns in the number of animals slaughtered and condemned; the reasons invoked for whole carcass condemnations; reporting biases and regional effects. RESULTS: Whole carcass condemnation rates were fairly uniform (1-2‰) over time and between the different types of production animals. Condemnation rates were much higher and less uniform following emergency slaughters. The number of condemnations peaked in December for both cattle and pigs, a time when individuals of lower quality are sent to slaughter when hay and food are limited and when certain diseases are more prevalent. Each type of production animal was associated with a different profile of condemnation reasons. The most commonly reported one was "severe lesions" for cattle, "abscesses" for pigs and "pronounced weight loss" for small ruminants. These reasons could constitute valuable syndromic indicators as they are unspecific clinical manifestations of a large range of animal diseases (as well as potential indicators of animal welfare). Differences were detected in the rate of carcass condemnation between cantons and between large and small slaughterhouses. A large percentage (>60% for all three animal categories) of slaughterhouses operating never reported a condemnation between 2007 and 2012, a potential indicator of widespread non-reporting bias in our database. CONCLUSIONS: The current system offers simultaneous coverage of cattle, pigs and small ruminants for the whole of Switzerland; and traceability of each condemnation to its farm of origin. The number of condemnations was significantly linked to the number of slaughters, meaning that the former should be always be offset by the later in analyses. Because this denominator is only communicated at the end of the month, condemnations may currently only be monitored on a monthly basis. Coupled with the lack of timeliness (30-60 days delay between condemnation and notification), this limits the use of the data for early-detection.