Higher-than-predicted saltation threshold wind speeds on Titan.

Titan, the largest satellite of Saturn, exhibits extensive aeolian, that is, wind-formed, dunes, features previously identified exclusively on Earth, Mars and Venus. Wind tunnel data collected under ambient and planetary-analogue conditions inform our models of aeolian processes on the terrestrial planets. However, the accuracy of these widely used formulations in predicting the threshold wind speeds required to move sand by saltation, or by short bounces, has not been tested under conditions relevant for non-terrestrial planets. Here we derive saltation threshold wind speeds under the thick-atmosphere, low-gravity and low-sediment-density conditions on Titan, using a high-pressure wind tunnel refurbished to simulate the appropriate kinematic viscosity for the near-surface atmosphere of Titan. The experimentally derived saltation threshold wind speeds are higher than those predicted by models based on terrestrial-analogue experiments, indicating the limitations of these models for such extreme conditions. The models can be reconciled with the experimental results by inclusion of the extremely low ratio of particle density to fluid density on Titan. Whereas the density ratio term enables accurate modelling of aeolian entrainment in thick atmospheres, such as those inferred for some extrasolar planets, our results also indicate that for environments with high density ratios, such as in jets on icy satellites or in tenuous atmospheres or exospheres, the correction for low-density-ratio conditions is not required.

Socioeconomic and geographical disparities in prescription and illicit opioid-related overdose deaths in Orange County, California, from 2010-2014.

Background: Reports indicate a geographic effect of socioeconomic inequalities on the occurrence of opioid-related fatal overdoses. This study aims to (1) estimate the rates of opioid-related overdoses, (2) estimate the association of benzodiazepine co-ingestion with opioid-related deaths, (3) estimate associations between socioeconomic indicators and opioid-related deaths, and (4) map the distribution of fatal overdoses, in Orange County (OC), California. Methods: An ecologic study was conducted of all opioid- related deaths (1205 total) from 2010 to 2014 obtained from the OC Coroner Division database (1065 OC residents, 55 nonresidents, 85 OC homeless) (analyzed 2016-2017). Rates of opioid overdose, benzodiazepine co-ingestion prevalence, and associations with socioeconomic status (SES; education, poverty, median income) using ZIP code analysis in the residential and homeless communities were calculated. Results: Of 1205 deaths, 904 involved prescription-type opioids, 223 involved heroin, 39 involved both, and 39 not stated; 973 were classified unintentional overdoses, 180 suicides, and 52 undetermined; 49% of cases involved benzodiazepines. Prescription-type opioid and heroin death rates for residents were 5.4/ 100,000 person-years (95% confidence interval [CI]: 5.0-5.8) and 1.2/100,000 person-years (95% CI: 1.0-1.4), respectively. Males, age group 45-54, and Caucasian race had the highest rate (13.6/100,000) of opioid mortality. The highest death rates were seen in homeless adults, at 136/100,000 person-years for prescription-type opioids (95% CI: 99.0-185.5) and 156/100,000 person-years for heroin (95% CI: 116.8-209.5). Conclusions: The burden of prescription-type opioid-related deaths in OC affects all demographics and levels of SES; there is a disproportionately high rate of opioid-related deaths in the OC homeless population.

An empirical estimate of carrier frequencies for 400+ causal Mendelian variants: results from an ethnically diverse clinical sample of 23,453 individuals.

PURPOSE: Recent developments in genomics have led to expanded carrier screening panels capable of assessing hundreds of causal mutations for genetic disease. This new technology enables simultaneous measurement of carrier frequencies for many diseases. As the resultant rank-ordering of carrier frequencies impacts the design and prioritization of screening programs, the accuracy of this ranking is a public health concern. METHODS: A total of 23,453 individuals from many obstetric, genetics, and infertility clinics were referred for routine recessive disease carrier screening. Multiplex carrier screening was performed and results were aggregated for this study. RESULTS: Twenty-four percent of individuals were identified as carriers for at least one of 108 disorders, and 5.2% were carriers for multiple disorders. We report tabulations of carrier frequency by self-identified ethnicity and disease. CONCLUSION: To our knowledge, this study of a large, ethnically diverse clinical sample provides the most accurate measurements to date of carrier frequencies for hundreds of recessive alleles. The study also yields information on the clinical considerations associated with routine use of expanded panels and provides support for a pan-ethnic screening paradigm that minimizes the use of "racial" categories by the physician, as recommended by recent guidelines.

Use of an unmanned aerial vehicle for monitoring and prediction of oilseed rape crop performance.

The flowering stage of oilseed rape (Brassica napus L.) is of vital interest in precision agriculture. It has been shown that data describing the flower production of oilseed rape (OSR), at stage 3, in spring can be used to predict seed yield at harvest. Traditional field-based techniques for assessing OSR flowers are based on a visual assessment which is subjective and time consuming. However, a high throughput phenotyping technique, using an unmanned aerial vehicle (UAV) with multispectral image (MSI) camera, was used to investigate the growth stages of OSR (in terms of crop height) and to quantify its flower production. A simplified approach using a normalised difference yellowness index (NDYI) was coupled with an iso-cluster classification method to quantify the number of OSR flower pixels and incorporate the data into an OSR seed yield estimation. The estimated OSR seed yield showed strong correlation with the actual OSR seed yield (R2 = 0.86), as determined using in-situ sensors mounted on the combine harvester. Also, using our approach allowed the variation in crop height to be assessed across all growing stages; the maximum crop height of 1.35 m OSR was observed at the flowering stage. This methodology is proposed for effectively predicting seed yield 3 months prior to harvesting.

Aortic puncture with a laparoscopic fascial closure device.

BACKGROUND: Vascular injury during laparoscopic surgery typically occurs with the blind insertion of either the Veress needle or the trocar. We report an aortic puncture from the use of a laparoscopic fascial closure device. CASE: After a laparoscopic-assisted vaginal hysterectomy and during closure of the 10-mm umbilical port with a fascial closure device, attempted passage of the needle encountered unusual resistance in the abdominal wall. Application of increased force resulted in uncontrolled entry of the needle into the abdominal cavity and a 1-mm puncture of the aorta. After emergency laparotomy the puncture was successfully repaired by a vascular surgeon. CONCLUSION: A previously unreported complication of this laparoscopic fascial closure device is aortic injury. Unusual resistance to passage of the needle should engender extra caution. The use of assistive closure devices should be reserved for patients with difficult anatomy.

Use of Physician-in-Triage Model in the Management of Abdominal Pain in an Emergency Department Observation Unit.

INTRODUCTION: Given the nationwide increase in emergency department (ED) visits it is of paramount importance for hospitals to find efficient ways to manage patient flow. The purpose of this study was to determine whether there is a significant difference in success rates, length of stay (LOS), and other demographic factors in two cohorts of patients admitted directly to an ED observation unit (EDOU) under an abdominal pain protocol by a physician in triage (bypassing the main ED) versus those admitted via the traditional pathway (evaluated and treated in the main ED prior to EDOU admission). METHODS: This was a retrospective cohort study of patients admitted to a protocol-driven EDOU with a diagnosis of abdominal pain in a single university hospital center ED. We obtained compiled data for all patients admitted to the EDOU with a diagnosis of abdominal pain that met EDOU protocol admission criteria. We divided data for each cohort into age, gender, payer status, and LOS. The data were then analyzed to assess any significant differences between the cohorts. RESULTS: A total of 327 patients were eligible for this study (85 triage group, 242 main ED group). The total success rate was 90.8% (n=297) and failure rate was 9.2% (n=30). We observed no significant differences in success rates between those dispositioned to the EDOU by triage physicians (90.6%) and those via the traditional route (90.5 % p) = 0.98. However, we found a significant difference between the two groups regarding total LOS with significantly shorter main ED times and EDOU times among patients sent to the EDOU by the physician-in-triage group (p< .001). CONCLUSION: There were no significant differences in EDOU disposition outcomes in patients admitted to an EDOU by a physician-in-triage or via the traditional route. However, there were statistically significant shorter LOSs in patients admitted to the EDOU by triage physicians. The data from this study support the implementation of a physician-in-triage model in combination with the EDOU in improving efficiency in the treatment of abdominal pain. This knowledge may spur action to cut healthcare costs and improve patient flow and timely decision-making in hospitals with EDOUs.

Oxidant enhancement in martian dust devils and storms: implications for life and habitability.

We investigate a new mechanism for producing oxidants, especially hydrogen peroxide (H2O2), on Mars. Large-scale electrostatic fields generated by charged sand and dust in the martian dust devils and storms, as well as during normal saltation, can induce chemical changes near and above the surface of Mars. The most dramatic effect is found in the production of H2O2 whose atmospheric abundance in the "vapor" phase can exceed 200 times that produced by photochemistry alone. With large electric fields, H2O2 abundance gets large enough for condensation to occur, followed by precipitation out of the atmosphere. Large quantities of H2O2 would then be adsorbed into the regolith, either as solid H2O2 "dust" or as re-evaporated vapor if the solid does not survive as it diffuses from its production region close to the surface. We suggest that this H2O2, or another superoxide processed from it in the surface, may be responsible for scavenging organic material from Mars. The presence of H2O2 in the surface could also accelerate the loss of methane from the atmosphere, thus requiring a larger source for maintaining a steady-state abundance of methane on Mars. The surface oxidants, together with storm electric fields and the harmful ultraviolet radiation that readily passes through the thin martian atmosphere, are likely to render the surface of Mars inhospitable to life as we know it.

Oxidant enhancement in martian dust devils and storms: storm electric fields and electron dissociative attachment.

Laboratory studies, numerical simulations, and desert field tests indicate that aeolian dust transport can generate atmospheric electricity via contact electrification or "triboelectricity." In convective structures such as dust devils and dust storms, grain stratification leads to macroscopic charge separations and gives rise to an overall electric dipole moment in the aeolian feature, similar in nature to the dipolar electric field generated in terrestrial thunderstorms. Previous numerical simulations indicate that these storm electric fields on Mars can approach the ambient breakdown field strength of approximately 25 kV/m. In terrestrial dust phenomena, potentials ranging from approximately 20 to 160 kV/m have been directly measured. The large electrostatic fields predicted in martian dust devils and storms can energize electrons in the low pressure martian atmosphere to values exceeding the electron dissociative attachment energy of both CO2 and H2O, which results in the formation of the new chemical products CO/O- and OH/H-, respectively. Using a collisional plasma physics model, we present calculations of the CO/O- and OH/H- reaction and production rates. We demonstrate that these rates vary geometrically with the ambient electric field, with substantial production of dissociative products when fields approach the breakdown value of approximately 25 kV/m. The dissociation of H2O into OH/H- provides a key ingredient for the generation of oxidants; thus electrically charged dust may significantly impact the habitability of Mars.

Growing Trend of Alternative Tobacco Use Among the Nation's Youth: A New Generation of Addicts.

The Centers for Disease Control and Prevention (CDC) has published significant data and trends related to the rising epidemic of usage of alternate forms of tobacco among the nation's youth. For the first time ever, the use of the electronic cigarette (e-cigarrette) has surpassed traditional cigarette usage in adolescents. E-cigarettes are battery-operated products designed to deliver aerosolized nicotine and other flavors to the consumer. Most look like conventional cigarettes but some resemble everyday items such as pens, USB drives, and memory sticks.1 In the following article, we present findings from the CDC's Morbidity and Mortality Weekly Report with commentary on the state of this growing epidemic and barriers to effective screening methods.

Recommendations for the appropriate use of anti-inflammatory drugs in the era of the coxibs: defining the role of gastroprotective agents.

Treatment with anti-inflammatory drugs and the analgesic efficacy of conventional nonsteroidal anti-inflammatory drugs (NSAIDs) are compromised by a two- to fourfold increased risk of gastrointestinal complications. This increased risk has resulted in an increasing use of the new selective cyclooxygenase-2 inhibitors or coxibs, which, in clinical trials and outcomes studies, reduced gastrointestinal adverse events by 50% to 65% compared with conventional NSAIDs. However, the coxibs are not available to all patients who need them, and NSAIDs are still widely used. Moreover, treatment with a coxib cannot heal pre-existing gastrointestinal lesions, and cotherapy with an anti-secretory drug or mucosal protective agent may be required. This paper addresses the management of patients with risk factors for gastrointestinal complications who are taking NSAIDs and makes recommendations for the appropriate use of 'gastroprotective' agents (GPAs) in patients who need to take an NSAID or a coxib. When economically possible, a coxib alone is preferable to a conventional NSAID plus a GPA to minimize exposure to potential gastrointestinal damage and avoid unnecessary dual therapy. Patients at high risk require a GPA in addition to a coxib.

An evidence-based approach to emergency department management of acute urinary retention.

Approximately 10% of men in their 70s and 33% of men in their 80s report at least 1 episode of acute urinary retention, and this urological emergency presents unique assessment and treatment challenges in the emergency department setting. Patients presenting with acute urinary retention are often in severe pain and require urgent diagnosis and prompt treatment. The differential diagnosis of acute urinary retention is vast, with some causes leading to permanent impairment if not dealt with in a timely manner. Quick recognition of the cause and timely bladder decompression are of utmost importance in preventing morbidity and relieving pain. This review analyzes the etiology, key historical and physical findings, differential diagnosis, and diagnostic studies for acute urinary retention in both men and women. Treatment algorithms for men and women, current controversies regarding urinary catheter usage, and recommendations on criteria for disposition are also presented.

Knowledge and attitudes regarding expanded genetic carrier screening among women's healthcare providers.

OBJECTIVE: To determine women's healthcare providers' knowledge and attitudes regarding genetic disorders and expanded genetic screening. DESIGN: Survey of American Society for Reproductive Medicine 2010 and American College of Obstetricians and Gynecologists 2011 Annual Meeting attendees. The survey included 60 items (12 demographic, 10 knowledge, and 38 attitude). Attitudes were assessed with a 5-point Likert scale. Chi-square or t tests determined significance. SETTING: American Society for Reproductive Medicine 2010 and American College of Obstetricians and Gynecologists 2011 Annual Meeting. PATIENT(S): A total of 203 participants completed the survey. Of these, 48% were male, 61% were physicians, 73% were Caucasian, and 42% were aged 35-50 years. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): None. RESULT(S): Physicians had better knowledge scores than other participants (87% vs. 79%). Knowledge was not influenced by prior personal/family experience with genetic screening. Fewer correct answers were observed for the probability of a positive test (65.2%), the risk of transmitting a gene mutation (62.2%), and the risk of having an affected child (56.2%). Very few participants (18.3%) disagreed with the notion of carrier screening as socially responsible behavior. Some had concerns about test result confidentiality (40.1%) and resulting insurance rate increases (37.0%). Assuming equal costs, most participants preferred to be tested for a larger number of diseases (77.7%) and believed posttest counseling to be helpful (83.7%). CONCLUSION(S): Women's healthcare providers generally had good knowledge and positive attitudes about genetic disorders and expanded genetic screening. Specific misperceptions, both medical and legal, require education.

Automated texture recognition of quartz sand grains for forensic applications.

Quartz sand surface texture analysis has been automated for the first time for forensic application. The derived Basic Image Features (BIFs) provide computer-generated texture recognition from preexisting data sets. The technique was applied to two distinct classification problems; first, the ability of the system to discriminate between (quartz) sand grains with upturned plate features (indicative of eolian, global sand sea environments) and grains that do not exhibit these features. A success rate of grain classification of 98.8% was achieved. Second, to test the ability of the computer recognition system to identify specific energy levels of formation of the upturned plate surface texture features. Such recognition ability has to date been beyond manual geological interpretation. The discrimination performance was enhanced to an exact classification success rate of 81%. The enhanced potential for routine forensic investigation of the provenance of common quartz sand is indicated.