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Positive symptoms are a useful predictor of aggression in schizophrenia. Although a similar pattern of abnormal brain structures related to both positive symptoms and aggression has been reported, this observation has not yet been confirmed in a single sample.
To study the association between positive symptoms and aggression in schizophrenia on a neurobiological level, a prospective meta-analytic approach was employed to analyze harmonized structural neuroimaging data from 10 research centers worldwide. We analyzed brain MRI scans from 902 individuals with a primary diagnosis of schizophrenia and 952 healthy controls.
The result identified a widespread cortical thickness reduction in schizophrenia compared to their controls. Two separate meta-regression analyses revealed that a common pattern of reduced cortical gray matter thickness within the left lateral temporal lobe and right midcingulate cortex was significantly associated with both positive symptoms and aggression.
These findings suggested that positive symptoms such as formal thought disorder and auditory misperception, combined with cognitive impairments reflecting difficulties in deploying an adaptive control toward perceived threats, could escalate the likelihood of aggression in schizophrenia.
We determined how pasture and grazing management practices affected the number of days hay was fed to cattle by season. Data were collected from a survey of Tennessee cattle producers. Days of cattle on hay varied across seasons because of variations in forage production and weather. The number of days hay was fed to cattle varied with pasture-animal management practices such as rotating pastures, forage mixtures, and weed management strategies. Having mixtures of cool- and warm-season grasses reduced the number of days on hay in the winter, spring, and summer months indicating benefits from diversified forages.
Introduction: Hypotension is known to be associated with increased mortality in severe traumatic brain injury (TBI) patients. Systolic blood pressure (SBP) of <90 mmHg is the threshold for hypotension in consensus TBI treatment guidelines; however, evidence suggests hypotension should be defined at higher levels for these patients. Our objective was to determine the influence of hypotension on mortality in TBI patients requiring ICU admission using different thresholds of SBP on arrival at the emergency department (ED). Methods: Retrospective cohort study of patients with severe TBI (Abbreviated Injury Scale Head score ≥3) admitted to ICU at the QEII Health Sciences Centre (Halifax, Canada) between 2002 and 2013. Patients were grouped by SBP on ED arrival ( <90 mmHg, <100 mmHg, <110 mmHg). We performed multiple logistic regression analysis with mortality as the dependent variable. Models were adjusted for confounders including age, gender, Injury Severity Score (ISS), injury mechanism, and trauma team activation (TTA). Results: A total of 1233 patients sustained a severe TBI and were admitted to the ICU during the study period. The mean age was 43.4 ± 23.9 years and most patients were male (919/1233; 74.5%). The most common mechanism of injury was motor vehicle collision (491/1233; 41.2%) followed by falls (427/1233; 35.8%). Mean length of stay in the ICU was 6.1 ± 6.4 days, and the overall mortality rate was 22.7%. SBP on arrival was available for 1182 patients. The <90 mmHg group had 4.6% (54/1182) of these patients; mean ISS was 20.6 ± 7.8 and mortality was 40.7% (22/54). The <100 mmHg had 9.3% (110/1182) of patients; mean ISS was 19.3 ± 7.9 and mortality was 34.5% (38/110). The <110 mmHg group had 16.8% (198/1182) of patients; mean ISS was 17.9 ± 8.0 and mortality was 28.8% (57/198). After adjusting for confounders, the association between hypotension and mortality was 2.22 (95% CI 1.19-4.16) using a <90 mmHg cutoff, 1.79 (95% CI 1.12-2.86) using a <100 mmHg cutoff, and 1.50 (95% CI 1.02-2.21) using a <110 mmHg cutoff. Conclusion: While we found that TBI patients with a SBP <90 mmHg were over 2 times more likely to die, patients with an SBP <110 mmHg on ED arrival were still 1.5 times more likely to die from their injuries compared to patients without hypotension. These results suggest that establishing a higher threshold for clinically meaningful hypotension in TBI patients is warranted.
High resolution Bragg-case X-ray double and triple axis diffractometry and Laue-case white beam synchrotron X-ray topography experiments have been performed on undoped  oriented float-zone GaAs crystals have been grown under microgravity conditions in space on the D2 mission. Near the seed, excellent anomalous transmission was achieved and a clear cellular structure of dislocations observed. The double and triple axis rocking curves were comparable with those from semi-insulating terrestrial material. Following a heater failure, the molten zone height dropped and reciprocal space maps revealed a long ridge of scatter transverse to the diffraction vector direction. This corresponds to the presence of a distribution of sub-grains containing little internal strain. Continued growth resulted in twin formation.
To examine the feasibility of using social media to assess the consumer nutrition environment by comparing sentiment expressed in Yelp reviews with information obtained from a direct observation audit instrument for grocery stores.
Trained raters used the Nutrition Environment Measures Survey in Stores (NEMS-S) in 100 grocery stores from July 2015 to March 2016. Yelp reviews were available for sixty-nine of these stores and were retrieved in February 2017 using the Yelp Application Program Interface. A sentiment analysis was conducted to quantify the perceptions of the consumer nutrition environment in the review text. Pearson correlation coefficients (ρ) were used to compare NEMS-S scores with Yelp review text on food availability, quality, price and shopping experience.
Detroit, Michigan, USA.
Yelp reviews contained more comments about food availability and the overall shopping experience than food price and food quality. Negative sentiment about food prices in Yelp review text and the number of dollar signs on Yelp were positively correlated with observed food prices in stores (ρ=0·413 and 0·462, respectively). Stores with greater food availability were rated as more expensive on Yelp. Other aspects of the food store environment (e.g. overall quality and shopping experience) were captured only in Yelp.
While Yelp cannot replace in-person audits for collecting detailed information on the availability, quality and cost of specific food items, Yelp holds promise as a cost-effective means to gather information on the overall cost, quality and experience of food stores, which may be relevant for nutrition outcomes.
Multi-sire mating of a mob of ewes is commonly used in commercial sheep production systems. However, ram mating success (defined as the number of lambs sired by an individual) can vary between rams in the mating group. If this trait was repeatable and heritable, selection of rams capable of siring larger numbers of lambs could reduce the number of rams required for mating and ultimately lead to increased genetic gain. However, genetic correlations with other productive traits, such as growth and female fertility, could influence the potential for ram mating success to be used as a selection trait. In order to investigate this trait, parentage records (including accuracy of sire assignment) from 15 commercial ram breeding flocks of various breeds were utilised to examine the repeatability and heritability of ram mating success in multi-sire mating groups. In addition, genetic and phenotypic correlations with growth and female fertility traits were estimated using ASReml. The final model used for the ram mating success traits included age of the ram and mating group as fixed effects. Older rams (3+years old) had 15% to 20% greater mating success than younger rams (1 or 2 years of age). Increasing the stringency of the criteria for inclusion of both an individual lamb, based on accuracy of sire assignment, or a whole mating group, based on how many lambs had an assigned sire, increased repeatability and heritability estimates of the ram mating success traits examined. With the most stringent criteria employed, where assignment of sire accuracy was >0.95 and the total number of lambs in the progeny group that failed to have a sire assigned was<0.05, repeatability and heritability for loge(number of lambs) was 0.40±0.09 and 0.26±0.12, respectively. For proportion of lambs sired, repeatability and heritability were both 0.30±0.09. The two ram mating traits (loge(nlamb) and proportion) were highly correlated, both phenotypically and genetically (0.88±0.01 and 0.94±0.06, respectively). Both phenotypic and genetic correlations between ram mating success and growth and other female fertility traits were low and non-significant. In conclusion, there is scope to select rams capable of producing high numbers of progeny and thus increase selection pressure on rams to increase genetic gain.
Major and trace element data are presented for the basic, intermediate, and acid rocks of the Beinn Chaisgidle Centre of the Tertiary igneous complex on the Isle of Mull. The variation in the bulk chemical composition, the iron enrichment trend in the clinopyroxenes, the systematic decrease in concentrations of the transition metal cations, and the increase in the incompatible elements suggest that the magma from which these rocks formed underwent crystal fractionation. The rocks show a coherence of rare earth element patterns for all the rocks in the sequence, and there is a progressive increase in negative Eu anomaly with increasing silica content.
Background: Secondary hormonal deficiency (SHD) in patients with sellar masses (SM) is associated with significant morbidity. Purpose: to compare long-term risk of new-onset SHD in SM found incidentally (ISM) versus those clinically manifesting (CMSM). Methods: From the Halifax Neuropituitary Program’s database, we identified all patients having non-functioning and non-pituitary SM from January 1, 2006, with ≥ 12 months follow-up. Results: There were 214 CMSM (108 with baseline SHD) and 148 ISM (37 with baseline SHD) patients (mean follow-up: 5.7 and 5.0 years, respectively). In patients who underwent early surgery (<90 days from diagnosis), 3-month post-op hormonal function was considered baseline. Despite unchanged tumour size in over 95%, 129 (35.6%) developed new-onset SHD at up to 120 months. The risk of developing new-onset SHD was similar in CMSM and ISM groups (HR = 1.10; CI= 0.69-1.75; p= 0.7), and in surgical and nonsurgical patients (HR=1.24; CI= 0.59-2.61; p = 0.58). Conclusions: More than one third of patients with non-functioning or non-pituitary SM, presenting either with clinical manifestations or as incidental lesions, will develop new-onset SHD. Furthermore, SHD may develop several years later and despite stability of tumors, highlighting the need for ongoing, long-term hormonal assessment.
Introduction: Our emergency department (ED) sees a low volume of high acuity pediatric cases. A needs assessment revealed that 68% of our Emergency Physicians (EP) manage pediatric patients in less than 25% of their shifts. The same percentage of EPs as well as ED nurses indicated they were uncomfortable managing a critically unwell neonate. Thus, an interprofessional curriculum focused on pediatric emergencies for ED staff was developed. In-situ simulation education was chosen as the most appropriate method to consolidate each didactic block of curriculum, and uncover important system gaps. Methods: Needs assessment conducted, and emerging themes informed IPE curriculum objectives. A committee of experts in simulation, pediatric emergencies and nursing education designed a full-day, RCPSC accredited, interprofessional in-situ simulation program. Results: Progressive segmental strategy maximized learning outcomes. The initial phase (2 hrs) comprised an” early recognition of sepsis” seminar and 4 rotating skills stations (equipment familiarity, sedating the child, IV starts, and mixing IV medication). This deliberate, adaptive, customized practice was enhanced by expert facilitation at each station, directly engaging participants and providing real-time feedback. The second phase allowed interprofessional teams of MDs, RNs and Physician Assistants to apply knowledge gained from the didactic and skills stations to in-situ simulated emergencies. Each group participated in two pediatric emergency scenarios. Scenarios ran 20 minutes, followed by a 40 minute debrief. Each scenario had a trained debriefer and content expert. The day concluded with a final debrief, attended by all participants. Formalized checklists assessed participants knowledge translation during simulation exercises. Participants assessed facilitators and evaluated the simulation day and curriculum via anonymous feedback forms. Debriefing sessions were scribed and knowledge gaps and system errors were recorded. Results were distributed to ED leaders and responsibilities assigned to key stakeholders to ensure accountability and improvement in system errors. Results All participants reported the experience to be relevant and helpful in their learning. All participants requested more frequent simulation days. System gaps identified included: use of metric vs imperial measurements, non-compatible laryngoscope equipment, inadequate identification of team personnel. As a result, the above-mentioned equipment has been replaced, and we are developing resuscitation room ID stickers for all team roles. Conclusion: Simulation as a culmination to a didactic curriculum provides a safe environment to translate acquired knowledge, increasing ED staff comfort and familiarity with rare pediatric cases. Additionally, is an excellent tool to reveal system gaps and allow us to fill these gaps to improve departmental functioning and safety.
Introduction: Tertiary care emergency departments (EDs) in large urban environments may have a low volume of high acuity pediatric presentations due to their proximity to dedicated childrens hospitals or large community centres. This may lead to discomfort among emergency physicians (EPs) and registered nurses (RNs) in managing these patients and a waning of knowledge and skills for this unique population. Among the EP group at our institution, 68% indicated they managed pediatric patients in less than 25% of their shifts, 68% also indicated they were uncomfortable managing an undifferentiated critically unwell neonate and only 32% indicated they would be comfortable teaching pediatric topics to emergency medicine residents. At our institution, our innovation was to create a useful curriculum for certified EPs and RNs to improve the interdisciplinary teams comfort level, knowledge and skill set when managing pediatric emergencies. Methods: A needs assessment was undertaken of the EPs and RNs working in our centre. This information was used to develop intended learning outcomes in a collaborative manner with the clinical nursing educator and physician curriculum leads. The team further collaborated with the local simulation centre and a pediatric emergency physician from the local childrens hospital. Results: A one-year, three-module curriculum was developed to cover the areas felt to be highest yield by the EP group: febrile illness, respiratory disease and critically ill neonates and infants. Each module contains three components: an in person interactive lecture delivered by an EP who routinely manages pediatric patients, either at a childrens hospital or large community centre; an online component with e-mail blasts of high yield pediatric content; and, culminating in an interdisciplinary interdepartmental simulation held in situ. This latter is particularly important so that all members of the interdisciplinary team can practice finding and using equipment based on its actual location within the ED. Each component of each module is then evaluated by the participants to ensure improvement for subsequent delivery. Conclusion: Well delivered continuing professional development (CPD) will become increasingly important as competence by design becomes the model for maintenance of certification. Maintaining skills for pediatric patients is an important component of CPD for physicians working in general emergency departments that see a low volume of high acuity pediatric presentations. Our curriculum seeks to address this identified need in an innovative manner using a modular and interdisciplinary approach with a diversity of teaching methods to appeal to the learning styles among our health care team.
J. E. Colwell, University of Central Florida Orlando, Florida, USA,
J. Blum, Technische Universität Braunschweig Braunschweig, GERMANY,
R. N. Clark, Planetary Science Institute Tucson, Arizona, USA,
S. Kempf, University of Colorado Boulder, Colorado, USA,
R. M. Nelson, Planetary Science Institute Tucson, Arizona, USA
The surface area of Saturn's rings is greater than that of any of the planets in the solar system, yet, aside from dust, we have never observed or sampled an individual ring particle. Rings are unique in the solar system in that they are a complex dynamical system whose individual constituents interact not only with the light that we use to sense them remotely, but also with each other through gravitational and contact forces. These dynamical interactions play as large a role in determining the appearance of the ring system as do the optical properties of the individual ring particles. In this chapter we review the experimental work that has been done to help us understand both aspects of planetary rings: their collective dynamical behavior and their optical properties.
We have a wealth of data on the behavior of ensembles of particles, both dynamically and their optical properties. Laboratory measurements of the behavior of various likely ring particle analogs are a critical link in connecting these bulk observations with the nature of individual ring particles, and understanding the properties of individual ring particles should provide clues to the outstanding unanswered questions about the age and origin of rings.
Images of Saturn's rings and optical depth profiles from occultations show features at a variety of spatial scales, from the resolution limit of tens of meters for occultations up to thousands of kilometers, and including most scales in between (Colwell et al., 2009; Chapter 3). A frustratingly small fraction of these structures is well understood. Many that remain puzzling, such as the large optical depth fluctuations in Saturn's central B ring, the complex structure in the B ring and the inner A ring, the long-wavelength low-amplitude undulations in optical depth in the C ring, and the plateaus in the C ring, are likely linked to either the collective behavior of the ring particles governed in part by their collisional properties (see e.g. Schmidt et al., 2009, for a review) or by ballistic transport of material due to extrinsic micrometeoroid bombardment (Chapter 9). The mechanical properties of individual ring particles are critical in both types of process.