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We examine the accuracy of density prediction by the first principles model Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) developed by the National Center for Atmospheric Research and compare it to the accuracy of three empirical models: Jacchia 71, the Naval Research Laboratory Mass Spectrometer Incoherent Scatter Extended 2000 (NRLMSIS), Jacchia 1971, and Jacchia‐Bowman 2008. Comparisons are made for three large storms: the October 2003 storm, the March 2013 storm, and the March 2015 storm. To evaluate the accuracy of these models we use tracking data for nine space objects in low Earth orbit. Additionally, we evaluate the accuracy of the TIEGCM and NRLMSIS with data from high precision accelerometers on the Challenging Minisatellite Payload (CHAMP) and Gravity field and Circulation Explorer (GOCE) satellites. The goal is to assess the use of a first principles model as a potential tool for forecasting satellite drag during large magnetic storms. For the storms considered, we found the TIEGCM, JB2008, and NRLMSIS models to be substantially more accurate than the Jacchia 71 model. The accuracies of the TIEGCM and JB2008 models were similar, but overall, the TIEGCM was more accurate. We found smaller differences for TIEGCM versus CHAMP than for NRLMIS for the Halloween Storm, and smaller differences than results published for JB2008 and the assimilative model HASDM. The empirical models are at present more practical for operational purposes, but the TIEGCM, developed as a research model, with a greater focus on operational use offers the potential for improved utility during stressing conditions. Plain Language Summary: We examined the accuracy of density prediction by the physics‐based Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) developed by the National Center for Atmospheric Research and compare it to the accuracy of three data‐based models: Jacchia 71, the Naval Research Laboratory Mass Spectrometer Incoherent Scatter Extended 2000 (NRLMSIS), Jacchia 1971 and Jacchia‐Bowman 2008 (JB2008). Comparisons are made for three large magnetic storms. To evaluate the accuracy of these models we use tracking data for nine space objects in low earth orbit. Additionally, we evaluate the accuracy of the TIEGCM and NRLMSIS with data from the Challenging Minisatellite Payload and Gravity field and Circulation Explorer satellites. The goal is to assess the use of a physics‐based model as a potential tool for forecasting satellite drag during large magnetic storms. For the three storms considered, we found the TIEGCM, JB2008, and NLMSIS accuracies to be substantially better than for Jacchia 71. The TIEGCM and JB2008 models were similar, but overall the TIEGCM was slightly more accurate. The empirical models are at present more practical operationally, but the TIEGCM was developed as a research model and with a greater focus on operational use offers the potential for improved utility during stressing conditions. Key Points: The accuracy of Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) density prediction during storms is compared to empirical models using tracking data for objects in low earth orbitTIEGCM accuracy is substantially better than the Jacchia 71 model during three large magnetic stormsThe accuracies of the TIEGCM and JB2008 models are similar, but overall, the TIEGCM was more accurate [ABSTRACT FROM AUTHOR]

Background and purpose For patients with acute ischaemic stroke due to large-vessel occlusion, it has recently been shown that mechanical thrombectomy ( MT) with stent retrievers is better than medical treatment alone. However, few hospitals can provide MT 24 h/day 365 days/year, and it remains unclear whether selected patients with acute stroke should be directly transferred to the nearest MT-providing hospital to prevent treatment delays. Clinical scales such as Rapid Arterial Occlusion Evaluation ( RACE) have been developed to predict large-vessel occlusion at a pre-hospital level, but their predictive value for MT is low. We propose new criteria to identify patients eligible for MT, with higher accuracy. Methods The Direct Referral to Endovascular Center criteria were defined based on a retrospective cohort of 317 patients admitted to a stroke center. The association of age, sex, RACE scale score and blood pressure with the likelihood of receiving MT were analyzed. Cut-off points with the highest association were thereafter evaluated in a prospective cohort of 153 patients from nine stroke units comprising the Madrid Stroke Network. Results Patients with a RACE scale score ≥ 5, systolic blood pressure <190 mmHg and age <81 years showed a significantly higher probability of undergoing MT (odds ratio, 33.38; 95% confidence interval, 12-92.9). This outcome was confirmed in the prospective cohort, with 68% sensitivity, 84% specificity, 42% positive and 94% negative predictive values for MT, ruling out 83% of hemorrhagic strokes. Conclusions The Direct Referral to Endovascular Center criteria could be useful for identifying patients suitable for MT. [ABSTRACT FROM AUTHOR]

Cosmogenic He, Ne, and Ar as well as the radionuclides 10Be, 26Al, 36Cl, 41Ca, 53Mn, and 60Fe have been determined on samples from the Gebel Kamil ungrouped Ni-rich iron meteorite by noble gas mass spectrometry and accelerator mass spectrometry ( AMS), respectively. The meteorite is associated with the Kamil crater in southern Egypt, which is about 45 m in diameter. Samples originate from an individual large fragment ('Individual') as well as from shrapnel. Concentrations of all cosmogenic nuclides-stable and radioactive-are lower by a factor 3-4 in the shrapnel samples than in the Individual. Assuming negligible 36Cl decay during terrestrial residence (indicated by the young crater age <5000 years; Folco et al. ), data are consistent with a simple exposure history and a 36Cl-36Ar cosmic ray exposure age ( CRE) of approximately (366 ± 18) Ma (systematic errors not included). Both noble gases and radionuclides point to a pre-atmospheric radius >85 cm, i.e., a pre-atmospheric mass >20 tons, with a preferred radius of 115-120 cm (50-60 tons). The analyzed samples came from a depth of approximately 20 cm (Individual) and approximately 50-80 cm (shrapnel). The size of the Gebel Kamil meteoroid determined in this work is close to estimates based on impact cratering models combined with expectations for ablation during passage through the atmosphere (Folco et al. , ). [ABSTRACT FROM AUTHOR]

Climate variability, changing land use and management, and dynamic policy environments are the main reasons why long-term research is needed to understand and predict possible water quality outcomes to alternative future scenarios. Long-term water quality data sets are needed to address these water issues. Such data sets were acquired by the USDA-ARS in three watersheds in Oklahoma: the Southern Great Plains Research Watershed (SGPRW), the Little Washita River Experimental Watershed (LWREW), and the Fort Cobb Reservoir Experimental Watershed (FCREW). We provide: (i) a description of these water quality data sets, (ii) the sample collection and processing procedures used and an assessment of the data quality, (iii) summary analyses of the variability in each data set, and (iv) details about how to access these data sets. Water quality data collection in the SGPRW began in the 1960s and continued through 1978, while that in the LWREW covered the 1960s to 1990 period. Data collection began in the FCREW in 2004 and continues through the present. The data were collected from streams, unit source watersheds, groundwater wells, and reservoirs. The water quality data described for a given site are generally complete for a given period of record; however, not all sites were monitored continuously and were not necessarily analyzed for the same water quality parameters. These data sets are expected to improve modeling and assessments of conservation practices in relation to climate variability, land use changes, and other environmental factors and may be useful in developing strategies to mitigate these environmental impacts. [ABSTRACT FROM AUTHOR]

Hydrologic, watershed, water resources, and climate-related research conducted by the USDA-ARS Grazinglands Research Laboratory (GRL) are rooted in events dating back to the 1930s. In 1960, the 2927-km² Southern Great Plains Research Watershed (SGPRW) was established to study the effectiveness of USDA flood control and soil erosion prevention programs. The size of the SGPRW was scaled back in 1978, leaving only the 610-km² Little Washita River Experimental Watershed (LWREW) to be used as an outdoor hydrologic research laboratory. Since 1978, the number of measurement sites and types of instruments used to collect meteorologic and soil climate data have changed on the LWREW. Moreover, a second research watershed, the 786-km² Fort Cobb Reservoir Experimental Watershed (FCREW), was added in 2004 to the GRL's outdoor research laboratories to further study the effects of agricultural conservation practices on selected environmental endpoints. We describe the SGPREW, FCREW, and LWREW and the meteorologic measurement network (historic and present) deployed on them, provide descriptions of measurements, including information on accuracy and calibration, quality assurance measures (where known), and data archiving of the present network, give examples of data products and applications, and provide information for the public and research communities regarding access and availability of both the historic and recent data from these watersheds. [ABSTRACT FROM AUTHOR]

Looking back 30 years ago, the advances in teaching have accompanied the technology evolution. As soon as the technology progressed, new teaching tools began to appear. This work describes one of these technological advances, Interactivity. Several definitions of Interactivity are presented from different points of view. Afterwards, the influence of Interactivity on teaching is discussed presenting the advantages and drawbacks of this information methodology on education. The Automatic Control education field is one of the areas where Interactivity has had a major influence. Hence, this works also describes why Interactivity is very important in engineering education, focusing in the Automatic Control field and presenting some interactive tools as examples of this fact. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 360-371, 2013 [ABSTRACT FROM AUTHOR]

To test the hypothesis that glycaemic control with exenatide added to thiazolidinediones (TZDs) with or without metformin was superior to placebo. A 26-week, multi-country (Canada, Mexico, Romania, South Africa and the USA), randomized, double-blind, placebo-controlled study compared exenatide twice-daily vs. placebo in 165 subjects suboptimally controlled with TZDs with or without metformin [HbA 8.2% (s.d. 0.9), fasting serum glucose 9.1 (2.6) mmol/l, body weight 93.9 (17.8) kg, diabetes duration 6.4 (4.3) years]. After a 2-week, single-blind, lead-in period, subjects were randomly assigned (2 : 1) to add exenatide or placebo to current regimens. The primary endpoint was HbA change at endpoint (Week 26 or last-observation-carried-forward). Only 8 subjects were treated with concomitant TZD alone. Exenatide reduced HbA significantly more than placebo [−0.84% (s.e. 0.20) vs. −0.10% (0.23), treatment difference −0.74% (0.16), p < 0.001)]. Mean reductions in body weight were similar in both treatments at endpoint [exenatide, −1.4 (s.e. 0.6) kg vs. placebo, −0.8 (0.7) kg, p = 0.176)]. Nearly 71% of subjects had both a reduction in HbA and body weight with exenatide compared with 54% with placebo. The most common adverse events (exenatide vs. placebo) were nausea (12% vs. 2%, p = 0.037), vomiting (8% vs. 0%, p = 0.031) and headache (4% vs. 4%). Confirmed (blood glucose <3.0 mmol/l) minor hypoglycaemia was experienced by 4 and 2% of subjects treated with exenatide and placebo, respectively. Incidence of hypoglycaemia was not significantly different between groups. Exenatide added to TZDs alone or in combination with metformin significantly improved glycaemic control as determined by significant improvement in HbA without associated hypoglycaemia. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses reactive blending of methyl-di(phenylethynyl)silane (MDPES) and modified bismaleimide resin (BMI/DBA). The study conducts thermogravimetric analysis to characterize the MDPES and BMI/DBA blends and scanning electron microscopy to determine surface morphology after thermal oxidative treatment. Results reveal that MDPES and BMI/DBA cure reaction occurs independently and the mixture was contributed to physical blends.

Rabies remains an important public health issue in Bolivia, South America. Public concern and fears are most focussed on dogs as the source of rabies. The objective of the present study was to assess immunity of an inactivated suckling mouse brain vaccine against canine rabies used for the official vaccination campaigns under field conditions in an endemic area of rabies in Bolivia. A total of 236 vaccinated and 44 unvaccinated dogs in Santa Cruz de la Sierra, selected using stratified random sampling, were investigated in order to obtain owned dog characteristics and antibody titres against rabies in April 2007. The proportion of vaccinated dogs with an antibody titre exceeded the protection threshold value of 0.5 EU/ml was 58% [95% confidence intervals (CI): 52–65], indicating that vaccination is likely to elicit an antibody response (odds ratio 6.3, 95% CI: 1.2–11.5). The range of geometric mean of antibody titre for vaccinated dogs (0.89 EU/ml; 95% CI: 0.75–1.04) was considered to meet the minimal acceptable level indicating an adequate immune response to the vaccine. However, the titre level was not satisfactory in comparison with the results from other field investigations with inactivated tissue culture vaccines. It is recommended for public health authorities to (1) consider modernizing their vaccine manufacturing method because the level of immunity induced by the current vaccine is comparably low, (2) conduct frequent vaccination campaigns to maintain high levels of vaccination coverage, and (3) actively manage the domestic dog population in the study area, which is largely responsible for rabies maintenance. [ABSTRACT FROM AUTHOR]

An unusual case of self-inflicted cesarean section with maternal and child survival is presented. No similar event was found in an Internet literature search. Because of a lack of medical assistance and a history of fetal death in utero, a 40-year-old multiparous woman unable to deliver herself alone vaginally sliced her abdomen and uterus and delivered her child. She was transferred to a hospital where she underwent repair of the incisions and had to remain hospitalized. Mother and child survived the event. Unusual and extraordinary measures to preserve their offspring sometimes moves women to extreme decisions endangering their own lives. Social, educational, and health measures should be instituted all over the world, particularly in rural areas of developing countries, to avoid such extreme events. [Copyright &y& Elsevier]

In a rat corticostriatal slice, brief, suprathreshold, repetitive cortical stimulation evoked longlasting plateau potentials in neostriatal neurons. Plateau potentials were often followed by spontaneous voltage transitions between two preferred membrane potentials. While the induction of plateau potentials was disrupted by non-NMDA and NMDA glutamate receptor antagonists, the maintenance of spontaneous voltage transitions was only blocked by NMDA receptor and L-type Ca&sup2+; channel antagonists. The frequency and duration of depolarized events, resembling up-states described in vivo, were increased by NMDA and L-type Ca&sup2+; channel agonists as well as by GABA[subA] receptor and K[sup+] channel antagonists. NMDA created a region of negative slope conductance and a positive slope crossing indicative of membrane bistability in the current-voltage relationship. NMDA-induced bistability was partially blocked by L-type Ca&sup2+; channel antagonists. Although evoked by synaptic stimulation, plateau potentials and voltage oscillations could not be evoked by somatic current injection - suggesting a dendritic origin. These data show that NMDA and L-type Ca&sup2+; conductances of spiny neurons are capable of rendering them bistable. This may help to support prolonged depolarizations and voltage oscillations under certain conditions. [ABSTRACT FROM AUTHOR]

A letter to the editor on dementia in patients with hypopituitarism is presented.

The new 2017 diagnostic criteria for hypermobile Ehlers-Danlos Syndrome (hEDS) provide a framework for diagnosing hEDS but are more stringent than the previous Villefranche criteria. Our clinical experience at the GoodHope EDS clinic was that the 2017 criteria left many highly symptomatic patients without a diagnosis of hEDS. We conducted a retrospective cohort study to confirm our clinic experience and assess the accuracy of the 2017 diagnostic criteria for hEDS in patients who had a previous hEDS diagnosis based on the Villefranche criteria. Our study found that 15% (n = 20 of 131) of patients with a prior diagnosis of hEDS met the 2017 diagnostic criteria, and many of the traits used to distinguish hEDS were not significantly more frequent in patients who met 2017 criteria versus those who did not. In both groups objective systemic manifestations were found less frequently than subjective systemic manifestations. Beighton score (BS) as assessed by primary care practitioner was found to be higher than assessment by EDS practitioner in 81% (n = 74 of 91) of cases. Generalized joint hypermobility was confirmed in only 46% (n = 51 of 111) of patients who had a previous diagnosis of hEDS. Higher BS did not correlate with increased number of systemic manifestations in our cohort. Common comorbidities of hEDS were found with similar frequency in those who met 2017 criteria and those who did not. Based on our cohort, the 2017 hEDS diagnostic criteria require refinement to improve its diagnostic accuracy., (© 2019 Wiley Periodicals, Inc.)

Background: previous evidence suggests young and new workers experience an increased risk of occupational injury. We sought to confirm this observation for healthcare workers., Methods: a retrospective cohort of 42,771 healthcare workers (88.2% women) was constructed from an active injury surveillance database. Over 2 years, incidence rates and crude and adjusted relative risks for occupational injury were compared between age groups and job tenures., Results: there were opposite trends in the two main types of injuries which cancelled each other: new workers and young workers had a decreased (not increased) risk of musculoskeletal sprain and strain injuries (adjusted RR [95% CI] for new hires was 0.60 [0.48, 0.73], and 0.85 [0.73, 0.98] for workers <25 years old); but an increased risk of cut and puncture injuries (1.25 [1.07, 1.45] for new hires, 1.28 [0.99, 1.67] for workers <25 years old)., Conclusions: contrary to studies of other sectors, younger age and shorter tenure were not universal risk factors for occupational injuries in the female dominated healthcare sector. Young and new workers had increased risk of cuts and punctures, but a decreased risk of musculoskeletal injuries., (2010 Wiley-Liss, Inc.)

Background: An essential assumption of injury prevention programs is the common cause hypothesis that the causal pathways of near misses and minor injuries are similar to those of major injuries., Methods: The rates of near miss, minor injury and major injury of all reported incidents and musculoskeletal incidents (MSIs) were calculated for three health regions using information from a surveillance database and productive hours from payroll data. The relative distribution of individual causes and activities involved in near miss, minor injury and major injury were then compared., Results: For all reported incidents, there were significant differences in the relative distribution of causes for near miss, minor, and major injury. However, the relative distribution of causes and activities involved in minor and major MSIs were similar. The top causes and activities involved were the same across near miss, minor, and major injury., Conclusions: Finding from this study support the use of near miss and minor injury data as potential outcome measures for injury prevention programs., ((c) 2008 Wiley-Liss, Inc.)