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Objective To describe the number of admissions of pregnant people to U.S. jails and the outcomes of pregnancies that end in custody. Methods We prospectively collected pregnancy data from six U.S. jails, including the five largest jails, on a monthly basis for 12 months. Jails reported de-identified, aggregate numbers of pregnant people admitted, births, preterm births, cesarean deliveries, miscarriages, induced abortions, ectopic pregnancies, and maternal and newborn deaths. Results There were 1,622 admissions of pregnant people in 12 months in the selected jails. The highest 1-day count of pregnant people at a single jail was 65. The majority of these admissions involved the release of a pregnant person. Of the 224 pregnancies that ended in jail, 144 (64%) were live births, 41 (18%) were miscarriages, 33 (15%) were induced abortions, and four were ectopic (1.8%). One third of the births were cesarean deliveries and 8% were preterm. There were two stillbirths, one newborn death, and no maternal deaths. Conclusion About 3% of admissions of females to U.S. jails are of pregnant people; extrapolating study results to national female jail admission rates suggests nearly 55,000 pregnancy admissions in 1 year. It is feasible to track pregnancy statistics about this overlooked group.

Objectives. To collect national data on pregnancy frequencies and outcomes among women in US state and federal prisons. Methods. From 2016 to 2017, we prospectively collected 12 months of pregnancy statistics from a geographically diverse sample of 22 state prison systems and the Federal Bureau of Prisons. Prisons reported numbers of pregnant women, births, miscarriages, abortions, and other outcomes. Results. Overall, 1396 pregnant women were admitted to prisons; 3.8% of newly admitted women and 0.6% of all women were pregnant in December 2016. There were 753 live births (92% of outcomes), 46 miscarriages (6%), 11 abortions (1%), 4 stillbirths (0.5%), 3 newborn deaths, and no maternal deaths. Six percent of live births were preterm and 30% were cesarean deliveries. Distributions of outcomes varied by state. Conclusions. Our study showed that the majority of prison pregnancies ended in live births or miscarriages. Our findings can enable policymakers, researchers, and public health practitioners to optimize health outcomes for incarcerated pregnant women and their newborns, whose health has broad sociopolitical implications.

Objective To understand abortion incidence among incarcerated people and the relation to prison and jail pregnancy policies. Methods We collected abortion numbers and policy data from convenience sample of 22 state prison systems, all Federal Bureau of Prisons sites, and six county jails that voluntarily reported monthly, aggregate pregnancy outcomes for 12 months in 2016-2017. Sites also completed a baseline survey of institution characteristics and pregnancy policies, including abortion. We reported facility policies and abortion incidence according to state-level abortion characteristics. Results Only half of state prisons in the study allowed abortion in both the first and second trimesters, and 14% did not allow abortion at all. Of the 19 state prisons permitting abortion, two thirds required the incarcerated woman to pay. Four jails of the six study jails (67%) allowed abortions in the first and second trimesters, and 25% of those required the incarcerated woman to pay for the procedure. The three prisons and two jails that did not allow abortions were in states considered hostile to abortion access. In the state and federal prisons studied, 11 of the 816 pregnancies (1.3%) that ended during the study time period were abortions. Of the 224 pregnancies that ended at study jails, 33 were abortions (15%), with more than half of those (55%) occurring in the first trimester. The abortion ratio (proportion of pregnancies ending in abortion) was 1.4% for prisons and 18% for jails. Conclusion Although some incarcerated individuals have abortions, many prisons and jails have restrictive policies surrounding abortion, either through self-payment requirements or explicit prohibition. Findings from this study should prompt further inquiry into abortion incidence in these settings and address interventions to ensure incarcerated people, in accordance with legal requirements and health equity, have access to abortion.

Introduction Patients presenting to the Emergency Department (ED) following head injury are frequently evaluated with an initial computed tomography scan (CT) of the brain. Imaging is particularly important in patients who are receiving medications that alter normal blood hemostasis. As an imaging modality, CT has a high negative predictive value when used to rule out clinically significant acute intracranial hemorrhage. Patients receiving anticoagulant or antiplatelet therapy have both an increased risk of initial hemorrhage, as well as an increased risk of mortality above nonanticoagulated patients, should they suffer hemorrhage. Multiple studies of delayed intracranial hemorrhage have placed the risk among the patients taking warfarin at the time of head injury in the range of 0.6-6.0%. However, data regarding the risk of delayed intracranial hemorrhage in patients taking the class of agents referred to as Direct-Acting Oral Anticoagulants (DOACs) remains limited. This study aims to estimate this risk. Methods A retrospective chart review was performed to identify patients on DOACs who presented to our Level I trauma center following blunt head injury between January 2017 and August 2018. Patients with a negative initial head CT were selected. From this subset, data regarding demographics, injury characteristics, anticoagulant use, and antiplatelet use were collected. Results Overall, 314 patients were included; 129 patients taking rivaroxaban, 182 patients taking apixaban, and four patients taking dabigatran. In approximately 29% of the patients, the sole indication for admission was close monitoring following head injury while taking an anticoagulant agent. The mechanism of injury for the majority of the patients was fall. Of the 314 patients, three were found to have delayed intracranial hemorrhage on the repeated head CT (0.95%). Two of these three patients were on concomitant antiplatelet medication. None of the three individuals required neurosurgical intervention. Conclusions at the time of submission, this is the largest study estimating the risk of delayed intracranial hemorrhage among patients on DOACs. Based on the results of this study, patients who sustain a blunt head injury while taking only DOACs; that is, without concurrent antiplatelet medication, admission, and repeat head CT may not be necessary after confirming a negative initial CT scan.

Objective Obesity has increased dramatically in the United States in recent decades. Our objective was to explore associations of contraceptive choices of US women, aged 20–44 years, with body mass index (BMI) and relevant covariates. Study design Data are based on interviews with a national sample of 11,300 women in the 2011–2015 National Survey of Family Growth. We analyzed women ages 20–44 at risk of unintended pregnancy. The primary dependent variable was BMI category. Covariates analyzed included age, parity, race/ethnicity, marital status, self-reported health and education. Data were analyzed via cross-tabulation and logistic regression. We determined unadjusted and adjusted odds ratios for three categories of contraceptive method: female sterilization, intrauterine device (IUD) and hormonal contraception. Results Obese women have higher odds of female sterilization (BMI 30.0–34.9 kg/m2: adjusted odds ratio (aOR) = 1.96, 95% confidence interval (CI) 1.45–2.66; BMI 35.0 kg/m2 and higher: aOR=1.56, 95% CI 1.13–2.14) compared to women with normal BMI. Odds of IUD use are significantly higher among women with BMI >35 kg/m2 (aOR=1.64, 95% CI 1.20–2.25). Odds of hormonal contraceptive use are correspondingly reduced (aOR=0.78, 95% CI 0.62–0.98) for women in the highest BMI category. Conclusions Contraceptive use varies by BMI category even after adjusting for usual correlates of use. Differences in contraceptive use by BMI category have implications for contraceptive counseling and provision. Implications Findings that obese women are more likely to rely on female sterilization raise questions about how weight concerns and obesity affect contraceptive decision making. Future research could explore associations between obesity and contraceptive use in adolescent women.

Clinical staff members all recognize the importance of attaining high patient satisfaction scores. Although there are many variables that contribute to patient satisfaction, implementation of a dog visitation program has been shown to have positive effects on patient satisfaction in total joint replacement patients. This innovative practice had not previously been studied in trauma patients. The purpose of this quasi-experimental study was to determine whether dog visitation to trauma inpatients increased patient satisfaction scores with the trauma physicians. A team consisting of a dog and handler visited 150 inpatients on the trauma service. Patient satisfaction was measured using a preexisting internal tool for patients who had received dog visitation and compared with other trauma patients who had not received a visit. This study demonstrated that patient satisfaction on four of the five measured scores was more positive for the patients who had received a dog visit.

An experimental campaign was recently completed at the U.S. Naval Research Laboratory’s Mercury pulsed-power facility, where the feasibility of using a 5 MV inductive voltage adder (IVA) as a pulsed photoneutron source was studied. In these experiments, a large-area bremsstrahlung diode was fielded on the Mercury accelerator, producing an intense, pulsed x-ray beam, which generated photoneutrons when striking an appropriate target. This paper reports on simulations that were performed to study the production of the electron beam in the diode, and the generation and transport of the x-ray beam. Comparison is made between the numerically predicted beam properties and results obtained during the experimental campaign. Various models of electron and ion emission from the electrodes in the generator were simulated, and the effect of model parameter choices on the dose predictions is described.

Statistical methods for genomewide association studies (GWAS) continue to improve. However, the increasing volume and variety of genetic and genomic data make computational speed and ease of data manipulation mandatory in future software. In our view, a collaborative effort of statistical geneticists is required to develop open source software targeted to genetic epidemiology. Our attempt to meet this need is called the OPENMENDELproject (https://openmendel.github.io). It aims to (1) enable interactive and reproducible analyses with informative intermediate results, (2) scale to big data analytics, (3) embrace parallel and distributed computing, (4) adapt to rapid hardware evolution, (5) allow cloud computing, (6) allow integration of varied genetic data types, and (7) foster easy communication between clinicians, geneticists, statisticians, and computer scientists. This article reviews and makes recommendations to the genetic epidemiology community in the context of the OPENMENDEL project., 16 pages, 2 figures, 2 tables

Objective This paper seeks to determine factors associated with nonuse of contraception by women at risk of unintended pregnancy in the United States. This nonuse may be associated with about 900,000 unintended births in the US each year. Study Design The 2002 and 2006–2010 National Surveys of Family Growth were combined to yield a nationally representative sample of 9,445 women at risk of unintended pregnancy. Logistic regression analyses identified factors associated with nonuse of contraception. Results This analysis reveals previously undocumented patterns of nonuse: controlling for confounding variables, cohabiting women [adjusted odds ratio (AOR)=2.3, 95% confidence interval (CI)=1.45–3.52] had higher odds of nonuse than married women; women who reported a difficulty getting pregnant (AOR=2.5, 95% CI=2.01–3.01) had higher odds of nonuse than those who did not. Nonuse was also more common among women with a master's degree or more (AOR=1.5, 95% CI=1.11–2.08) compared with those with some college or bachelor's degree, and it was more common among women in their first year after first intercourse than after the first year (AOR 1.6, 95% CI=1.12–2.22). Among women who had a recent unintended birth, the most common reason for not using contraception prior to conception was that she did not think she could get pregnant. Conclusions This study establishes national estimates of reasons for nonuse of contraception and identifies some new subgroups at risk of nonuse. Implications These results may help better understand factors affecting nonuse of contraception and develop strategies for preventing unintended pregnancy in the United States.

Objective The objective was to determine population-based estimates of use of contraception among women 15–44 years of age in the United States by disability status. Study design We examined the relationship between disability status and use of contraception among 7505 women at risk of unintended pregnancy using data from the 2011–2015 National Survey of Family Growth. Results After examining the full distribution of contraceptive method use by disability status, we found that disability status was significantly associated with differences in three categories of use: female sterilization, the oral contraceptive pill and nonuse of contraception. Multivariate analysis shows that use of female sterilization was higher among women with cognitive disabilities (aOR=1.54, 95% CI=1.12–2.12) and physical disabilities (aOR=1.59, CI=1.08–2.35) than for those without disabilities after controlling for age, parity, race, insurance coverage and experience of unintended births. Use of the pill was less common among women with physical disabilities than for those without disabilities (aOR=0.57, CI=0.40–0.82). Finally, not using a method was more common among women with cognitive disabilities (aOR=1.90, CI=1.36–2.66). Conclusions Self-reported cognitive disabilities (“serious difficulty concentrating, remembering or making decisions”), as well as physical disabilities, are significant predictors of contraceptive choices after controlling for several known predictors of use. Implications The patterns found here suggest that screening for self-reported cognitive and physical disabilities may allow health care providers to tailor counseling and sex education to help women with disabilities prevent unintended pregnancy and reach their family size goals.

Background A substantial and increasing population of US women of childbearing age live with disability. Disability-based disparities in access to family planning services have been previously documented, but few studies have used population-based data sources or evidence-based measures of disability. Objective To determine population-based estimates of use of family planning services among women 15–44 years of age in the United States, and to examine differences by disability status. Methods This is a secondary analysis of a cross-sectional survey, the 2011–2015 National Survey of Family Growth. These analyses include 11,300 female respondents between the ages of 15 and 44 who completed in-person interviews in respondents' homes. Results Approximately 17.8% of respondents reported at least one disability in at least one domain. Women with disabilities were less likely than those without disabilities to receive services; the largest differences by disability status were seen among women with low education, low income, and those who were not working. Logistic regression analysis suggests that women with physical disabilities and those with poorer general health are less likely to receive services. Conclusions Women living with disabilities reported lower receipt of family planning services compared to women without disabilities, but the differences were small in some subgroups and larger among disadvantaged women. Physical disabilities and poor health may be among the factors underlying these patterns. Further research is needed on other factors that affect the ability of women with disabilities to obtain the services they need to prevent unintended pregnancy.

There is an interest in 10 keV to 100 keV radiation sources for some types of radiation-interaction studies. The approach presented here uses non-thermal radiation from single-wire radiators (SWRs). An SWR is a high-Z exploding wire that produces many small, bright radiation sources along its length during a fast (< 100 ns) high-current (∼ MA) discharge. In previous experiments,2 tungsten wires produced spectra with 60 J above 10 keV with an effective endpoint of about 100 keV. An array of many, non-interacting SWRs is proposed to generate a higher yield in this energy range.

Direct irradiation of materials by electron beams (e-beams) has been used to study material response.2,3 The desire to utilize high-power (∼ TW) generators to achieve higher specific energy deposition over larger areas has led to several approaches. One approach utilizes a monolithic e-beam diode with an external magnetic field (B field). The external B field allows the diode to operate in the bipolar, space-charge-limited regime without the current being magnetically limited to a lower value. The field also is used to guide the e-beam through the gas-filled region between the vacuum diode and the object to be irradiated. An alternate approach, discussed in this presentation, utilizes multiple diodes electrically in parallel, with each diode running below the critical current to obtain a high current. The e-beams are then scattered in foils and combined in the gas-transport region to achieve the desired irradiation uniformity and area. We report on experiments that have been performed on the Gamble II generator at NRL (∼ 1 MV, ∼ 800 kA, ∼ 60 ns) designed to study this second approach. Diagnostics include diode voltage and current, a net-current monitor, interferometry, spectroscopy, an axial array of Ta-strip x-ray witness plates, and a segmented calorimeter. Experiments have been performed with a single ring diode and two nested ring diodes. Where possible, the measurements are compared with results from ITS and from the recently-developed ABC model4 for the interaction of the e-beam with the gas. Results show that the beam is very nearly charge and current neutralized as it propagates ∼ 20 cm in 1-Torrr N2 gas. Beam scattering from both the anode and a Ti scattering foil in the gas results in a relatively uniform radial beam profile.

Venous thromboembolism (VTE) continues to be an important complication for patients with trauma, including patients with intracranial hemorrhage. We implemented a protocol starting chemical prophylaxis 24 hours after the absence of progression of hemorrhage on computed tomography (CT) to increase consistency with the use of chemical venous thromboembolic prophylaxis in this population. The objective of this study was to review the protocol of VTE prophylaxis for patients with traumatic brain injury at our institution to determine whether it has been effective and safe in preventing VTE without increasing intracranial hemorrhage.A retrospective case series was conducted to study 205 patients with intracranial hemorrhage admitted to a Level I trauma center during a 24-month period. These patients were reviewed with respect to type of intracranial injury, need for surgery, injury severity, time to initiation of chemical prophylaxis, and progression of injury on brain CT. Patients with a hospital length of stay less than 3 days or nonstable CT were excluded in the analysis of administration of chemical prophylaxis. Time to chemical prophylaxis in relation to absence of progression on brain CT was examined as well as the subsequent risk of progression of hemorrhage and risk of VTE events. The overall rate of venous thromboembolism was compared with that of matched historical controls.All patients received mechanical prophylaxis in the form of sequential compression devices. One hundred sixty-two intracranial hemorrhages were identified in 122 patients who met the study's inclusion criteria. Of this group of patients who did not have progression of hemorrhage on follow-up CT, 76.2% received chemical prophylaxis during their hospitalization.No patients had progression of intracranial hemorrhage after initiation of chemical VTE prophylaxis, and no patients developed VTE. This represents a decrease of VTE from previous years. No other complications related to chemical VTE prophylaxis were identified.A protocol based on an early use of chemical venous thromboembolic prophylaxis after the absence of progression of tramatic intracranial hemorrhage does not result in increased progression of intracranial hemorrhage and reduced the rate of venous thromboembolic events at our institution.

Ever since the introduction of radiographic imaging, its utility in identifying injuries has been well documented and was incorporated in the workup of injured patients during advanced trauma life support algorithms [American College of Surgeons, 8th ed. Chicago, 2008]. More recently, computerized tomography (CT) has been shown to be more sensitive than radiography in the diagnosis of injury. Due to the increased use of CT scanning, concerns were raised regarding the associated exposure to ionizing radiation [N Engl J Med 357:2277–2284, 2007]. During the last several years, a significant amount of research has been published on this topic, most of it being incorporated in the BEIR VII Phase 2 report, published by the National Research Council of the National Academies [National Academy of Sciences, Washington DC, 2006]. The current review will analyze the scientific basis for the concerns over the ionizing radiation associated with the use of CT scanning and will examine the accuracy of the typical advanced trauma life support work-up for diagnosis of injuries.

The overall incidence is increasing by 2% per year for unknown reasons. New targeted systemic therapies, which have been integrated into clinical practice with evolving experience, have been available for more than 5 years. Preservation of kidney func-tion with widespread adoption of partial nephrectomy is a focus of treatment of early stage disease. These and other advances have revolutionized care and stimulated research and discovery. There are several guidelines in Canada that address various aspects of patient care in RCC.

This paper analyzes the Intense Pulsed Active Detection (IPAD) approach for active detection of fissile material, highlights some of its merits, and compares it to the multiple-pulse-train LINAC approach. In both cases, bremsstrahlung photons are used to induce fissions. IPAD's single, 100-ns bremsstrahlung pulse offers the possibility to utilize prompt as well as delayed neutrons emitted during the fission process. A combination of the ITS and MCNPX codes is used to characterize the dose to human tissue and both the prompt and delayed neutron emissions from the induced fissions for incident bremsstrahlung spectra between 6 and 50 MeV. No effects from shielding or from the interaction of the bremsstrahlung with the environment (water, air, etc) have been included in these computations, but these effects are a topic of ongoing work. Curves are developed that give the number of useful prompt neutrons per unit dose and the total number of delayed neutrons per unit dose that are independent of both the total electron charge delivered to the bremsstrahlung converter and the source-to-object distance. Useful prompt neutrons are defined to be those with energies exceeding the highest energy photo-neutron expected from 207Pb for a given bremsstrahlung endpoint energy. The analysis shows that endpoint energies between 9 and 13 MeV are optimum for the production of useful prompt neutrons/dose. Because the prompt signal is very fast, the detection of just two useful prompt neutrons gives a false alarm rate from cosmic-ray neutrons of less than 1 in 106. The analysis for delayed neutrons shows that above 14 MeV endpoint energies, both the neutron production and the dose increase as the endpoint energy squared. This suggests that, for a fixed body dose, no additional delayed neutrons are created above an endpoint energy of 14 MeV. A comparison of the multiple-pulse pulse-train LINAC approach and the single-pulse IPAD approach for detecting delayed neutrons is also presented. Because the 3-s detection time for the IPAD system is so much shorter than the 120-s detection time for the LINAC system, the IPAD system produces a signal that is much easier to separate from the cosmic-ray neutron background. This shorter time allows an IPAD system to detect fissile objects with 100% detection rate at a false alarm rate from cosmic-ray neutrons of less than 10"6 compared with a 50% detection rate for a 10% false alarm rate for the LINAC approach. Alternatively, the same detection efficiency as the LINAC approach is obtained with the detector about 2.7 times farther away from the fissile object.

Fifteen million strokes occur worldwide each year with 5 million associated deaths and an additional 5 million people left permanently disabled. In the United States, about 780 000 people suffer a new or recurrent stroke each year. There were an estimated total 5.8 million stroke survivors as of 2008. Mortality from stroke is the third leading cause of death in America following heart disease and cancer. Chest infection may affect up to as many as one-third of stroke patients. This increases the morbidity and mortality of this patient population. Pneumonia causes the highest attributable mortality of all medical complications following stroke. A comprehensive multidisciplinary team approach is required at the hospital level. This requires active administrative commitment and participation. Implementation of evidence-based management strategies can improve outcomes and reduce costs. We sought to review the problem of post-stroke pneumonia and discuss strategies for prevention and intervention.

Background Evidence-based medicine has gained wide acceptance in practice of medicine since the 1990s. The objective of our study was to demonstrate the effect of evidence-based critical care practices on ICU and hospital length of stay in mechanically ventilated trauma patients. Materials and Methods Retrospective cohort using historic controls. During 2004, several different evidence-based practices were implemented, including low tidal volume ventilation, protocol driven trauma resuscitation, and a sepsis bundle. Outcomes in critically ill, mechanically ventilated patients who were ≥ 18 y old were compared between a historic control group (2000–2003) and the study group after implementation (2005–2008). Patients were identified using the institutional trauma registry (NATIONAL TRACS). Gender, age, ISS, mechanism of injury, and mortality were also examined to identify trends in epidemiology. Results From 2000 to 2003. there were 6920 trauma admissions and during 2005–2008 there were 8911 (increase of 28.8%). These included 217 and 337 (increase of 55.3%) admissions to the ICU of mechanically ventilated patients, respectively. The mean age was 43.9 y versus 45.9 y (P = 0.258). Males were 66.4% versus 71.8% (P = 0.610). The mean ISS was 29 versus 27 (P = 0.25). Blunt mechanism was 87% versus 89% (P = 0.913). Mortality rate was 36.4% versus 36.5% (P = 0.944). The mean number of ICU days and hospital days decreased from 7.6 versus 5.5 (P = 0.02) and 13.2 versus 9.7 (P = 0.03), respectively. Conclusion The application of evidence-based critical care practices decreases length of ICU and hospital stay, but not mortality, in critically ill, mechanically ventilated trauma patients. Our trauma volume, including critically ill patients, increased during the study periods.

Hematocrit (Hct), systolic blood pressure (SBP), and heart rate (HR) are considered to closely correlate with hypovolemia in injured patients. The clinical importance of these parameters in the early recognition of occult but clinically significant hemorrhage remains to be demonstrated. We undertook this study to assess the clinical importance of these parameters in the early recognition of occult hemorrhage in injured patients. A retrospective study of 7880 patients admitted to a Level I trauma center was carried out. Patients who underwent surgery were divided into the hemorrhage (n = 160) and no-hemorrhage group (n = 228). Hematocrit, SBP, and HR were correlated and receiver operating characteristic (ROC) curves were plotted. The ROC curves for Hct, SBP, and HR showed suboptimal areas under the graph. Even for different Hct thresholds and for hypotension and tachycardia, low predictive values were found. Although Hct, SBP, and HR levels were significantly altered among patients who require surgery for hemorrhage, the low predictive values of each parameter renders them as clinically unreliable individual tools for recognition of hemorrhagic patients who need surgery. Although useful in aggregate, as a pattern, or as indications for further diagnostic studies, these common parameters have limited usefulness individually

The plasma-filled rod-pinch diode (PFRP) is a new X-ray source appropriate for pulsed hydrodynamic radiography with endpoint voltage in the 1-2 MV range. The use of a plasma prefill in a rod-pinch-electrode configuration results in intense concentration of a 150-300 kA, ~2 MeV, ~100 ns electron beam at the tip of a tapered tungsten rod, producing an X-ray source with a submillimeter diameter and a dose of 25 rad (CaF2) at a distance of 1 m. These parameters are superior to conventional vacuum diodes used for radiography in this electron-beam energy range. The narrow X-ray source distribution and enhanced emission of X-rays with energies less than 300 keV are unique features of the PFRP that may be exploited for improved resolution and dynamic range for radiographic applications.

Off-state degradation in drain-extended NMOS transistors is studied. Carefully designed experiments and well-calibrated simulations show that hot carriers, which are generated by impact ionization of surface band-to-band tunneling current, are responsible for interface damage during off-state stress. Classical on-state hot carrier degradation has historically been associated with broken equivSi-H bonds at the interface. In contrast, the off-state degradation in drain-extended devices is shown to be due to broken equivSi-O- bonds. The resultant degradation is universal, which enables a long-term extrapolation of device degradation at operating bias conditions based on short-term stress data. Time evolution of degradation due to broken equivSi-O- bonds and the resultant universal behavior is explained by a bond-dispersion model. Finally, we show that, under off-state stress conditions, the interface damage that is measured by charge-pumping technique is correlated with dielectric breakdown time, as both of them are driven by broken equivSi-O- bonds.

Summary form only given. The self-magnetic-pinch [SMP] diode is a high impedance (~40-Ohm), low R/D (typically 4 mm/8 mm) pinched-beam diode that shows promise for high-power X-radiography. The scaling of this diode to higher voltage (and thus power) is critical to the development of next generation radiographic sources. We report here on SMP experiments on the NRL Mercury generator at voltages from 3.5-6 MV and impedances from 35-50 Ohms. Measurements include diode electrical behavior, time-integrated and time-resolved X-ray dose, and time integrated radiographic spot size. We have studied the effects of several variations in electrode geometry, surface coating, gap; and the level of machine prepulse. Extensive modeling using the Sandia ITS codes is used to help interpret the X-ray dose and spot measurements. As the operating voltage increases, we find that a given diode tends to produce a smaller spot but also suffer reduced impedance lifetime, and optimization involves increasing the cathode diameter and diode gap as the voltage increases. We find good quantitative agreement with ITS predictions over the entire data set, assuming an electron incidence angle of 20 degrees. This gives a dose rate that scales (over the range examined) as IV2.2. Over this range, we observe favorable scaling of optimized diode performance with voltage, with good dose scaling and a slight spot size decrease with voltage. Our best results comprise roughly 200 rads at 1 meter with a ~2 mm diameter spot

STUDY QUESTION What factors and subgroups have propelled the recent increase in intrauterine device (IUD) use in the USA? SUMMARY ANSWER The increase in IUD use, from 1.8 to 9.5% in the USA between 2002 and 2012, was driven primarily by a marked uptake among parous women who intended to have more children. WHAT IS KNOWN ALREADY Recent data suggest an unprecedented increase in IUD use among women in the USA, yet less is known about how this increase has affected the overall proportion of women, at risk of unintended pregnancy, who are using contraception and which social and economic groups are involved. STUDY DESIGN, SIZE, DURATION Data are drawn from the 2002 and 2011-2013 National Surveys of Family Growth. The surveys were based on cross-sectional, national samples of women of 15-44 years of age in the USA. Women responded to in-person interviews, which lasted an average of 80 min. The response rate was 80% in 2002 and 73% in 2011-2013. The sample included 7643 completed interviews in 2002 and 5601 interviews in 2011-2013. PARTICIPANTS/MATERIALS, SETTING, METHODS This study was limited to women at risk of unintended pregnancy, i.e. women who were sexually active in the previous 3 months (using contraception or not); it excludes women who were sterile, currently pregnant or trying to conceive. Altogether, 5181 women were at risk in the 2002 sample and 3681 were at risk in the 2012 sample. We used descriptive statistics to investigate trends in contraceptive use patterns by women's sociodemographic characteristics between 2002 and 2012 and used logistic regression to identify current predictors of IUD use in 2012. MAIN RESULTS AND THE ROLE OF CHANCE IUD use increased from 1.8% in 2002 to 9.5% in 2012 (P < 0.001). The surge was especially marked among parous women who intended to have more children (4.2% in 2002 to 19.3% in 2012; P < 0.001); it occurred to a lesser extent among parous women who did not intend to have more children (2.0-9.7% P < 0.001), suggesting that IUDs are more often used for spacing than for ending childbearing in the USA. The most important predictors of IUD use in 2012 were age, parity and intent to have children. Dissatisfaction with a previous method was also associated with IUD use (adjusted odds ratio = 1.89, P < 0.001). LIMITATIONS, REASONS FOR CAUTION As with all cross-sectional studies, causal inference is limited. Data are self-reported, but the survey had a high response rate and rigorous quality controls. WIDER IMPLICATION OF THE FINDINGS This study shows promising trends in the use of highly effective contraceptive methods in the USA, which may help to explain recently reported declines in unintended pregnancy in the USA. STUDY FUNDING/COMPETING INTERESTS Caroline Moreau was supported by the William Robertson endowment funds. The work of Hannah Lantos and William Mosher on this analysis was supported by the Department of Population Family and Reproductive Health, The Johns Hopkins Bloomberg School of Public Health. The authors declare that no conflict of interest exists.

Self-magnetic-pinched diode behavior at 1.5-2 MV was diagnosed using a variety of electrical, radiation, and optical diagnostics. Results are compared with predictions of the LSP particle-in-cell code, and shown to be in good agreement. A practical diagnostic of electron incidence angles is demonstrated. A quadrature interferometer is shown to be capable of measuring the time-dependent position of the effective electrode-plasma boundaries. Both one-dimensional (1-D) and two-dimensional (2-D) interferometry show the importance of anode plasma expansion in such diodes with high anode-power concentration. Not only does the anode plasma contribute significantly to gap closure, but there is evidence that anode plasma expansion results in a distortion of the effective anode shape, which can significantly affect the diode performance.

The merits of several high-resolution, pulsed-power-driven, flash X-ray sources are examined with numerical simulation for voltages up to 10 MV. The charged particle dynamics in these self-magnetically pinched diodes (SMPDs), as well as electron scattering and energy loss in the high-atomic-number target, are treated with the partic by coupling the output from LSP with the two-dimensional component of the integrated tiger series of Monte Carlo electron/photon transport codes, CYLTRAN. The LSP/CYLTRAN model agrees well with angular dose-rate measurements from positive-polarity rod-pinch-diode experiments, where peak voltages ranged from 5.2-6.3 MV. This analysis indicates that, in this voltage range, the dose increases with angle and is a maximum in the direction headed back into the generator. This suggests that high-voltage rod-pinch experiments should be performed in negative polarity to maximize the extracted dose. The benchmarked LSP/CYLTRAN model is then used to examine three attractive negative-polarity diode geometry concepts as possible high-resolution radiography sources for voltages up to 10 MV. For a 2-mm-diameter reentrant rod-pinch diode (RPD), a forward-directed dose of 740 rad(LiF) at 1 m in a 50-ns full-width at half-maximum radiation pulse is predicted. For a 2-mm-diameter nonreentrant RPD, a forward-directed dose of 1270 rad(LiF) is predicted. For both RPDs, the on-axis X-ray spot size is comparable to the rod diameter. A self-similar hydrodynamic model for rod expansion indicates that spot-size growth from hydrodynamic effects should be minimal. For the planar SMPD, a forward-directed dose of 1370 rad(LiF) and a similar X-ray spot size are predicted. These results show that the nonreentrant RPD and the planar SMPD are very attractive candidates for negative-polarity high-resolution X-ray sources for voltages of up to 10 MV.

The laser wavefront analyzer (LWA) consists of a polarized laser beam pulse that traverses an imploding z-pinch, and a microlens array that focuses the laser beam into a large number (104) of very tiny spots. LWA image analysis determines the refractive bending angles (due to density gradients) and Faraday rotation angles (due to the magnetic field-density integral) throughout the plasma cross section. Electron density and current distributions are derived from LWA data in an imploding gas-puff z-pinch plasma.

The plasma-filled rod-pinch diode is a new technique to concentrate an intense electron beam to high power and energy density. Current from a pulsed power generator (typically ∼MV, MA, 100 ns pulse duration) flows through the injected plasma, which short-circuits the diode for 10–70 ns, then the impedance increases and a large fraction of the ∼MeV electron-beam energy is deposited at the tip of a 1 mm diameter, tapered rod anode, producing a small (sub-mm diameter), intense x-ray source. The current and voltage parameters imply 20–150 μm effective anode-cathode gaps at the time of maximum radiation, much smaller gaps than can be used between metal electrodes without premature shorting. Interferometric diagnostics indicate that the current initially sweeps up plasma in a snowplow-like manner, convecting current toward the rod tip. The density distribution is more diffuse at the time of beam formation with a low-density region near the rod surface where gap formation could occur. Particle simulations of the...

Salvinorin A is a unique hallucinogen that is seeing increased use in humans. It is not currently a controlled substance and is used as a legal alternative to controlled substances. Usually smoked or buccally absorbed by chewing, doses of approximately 200 mcg can produce profound hallucinogenic effects of short duration. The mechanism of action of salvinorin A is at the kappa-opioid receptor. Little data is available on the medical effects of this substance so animal studies were undertaken to explore the acute toxic effects of this substance in rats and the chronic effects in mice. Rats were anesthetized and administered salvinorin A at 1600 mcg/kg or vehicle. Recordings were made of galvanic skin response, EKG, temperature, and pulse pressure for 100 minutes. Mice were chronically exposed to vehicle or 400, 800, 1600, 3200, or 6400 mcg/kg of salvinorin A for two weeks. After exposure the animals were sacrificed and brain, heart, kidney, bone marrow, blood and spleen were removed, fixed, sectioned, stained and examined by light microscopy. No effects were seen on cardiac conduction, temperature, or galvanic skin response. A nonsignificant rise was seen in pulse pressure. Histologic studies of spleen, blood, brain, liver, kidney, and bone marrow did not find any significant histologic changes at any of the doses examined. These data suggests that the toxicity of salvinorin A is relatively low, even at doses many times greater than what humans are exposed to. However, further studies should be done on blood pressure effects. The psychological impact of this potent hallucinogen should also be investigated.

Purpose: The surgical resident experience with trauma has changed. Many residents are exposed to predominantly nonoperative patient care experiences while on trauma rotations. Data from a large multicenter study were analyzed to estimate surgical resident exposure to trauma laparotomy, diagnostic peritoneal lavage (DPL), and focused abdominal sonography for trauma (U/S). Methods: Centers completed a self-report questionnaire on their institutional demographics, admissions, and procedure for a 2-year period (1998-1999). Results: A total of 82 trauma centers that provide resident teaching were included. The included centers represent over 247,000 trauma admissions. The majority of trauma centers (65.9%) had > 80% blunt injury. Although all centers performed laparotomies, other results were more variable. For U/S, 24.2% performed none at all and 47.0% performed fewer than two U/S examinations per month. For DPLs, 3.8% performed none and 66.7% performed fewer than two per month. Assuming 1 night of 4 on call, the average surgical resident training at a trauma center performing > 80% blunt trauma has the potential to participate in only 15 trauma laparotomies, 6 diagnostic peritoneal lavages, and 45 ultrasound examinations per year. In addition, the resident will care for an average of 500 blunt trauma patients before performing a splenectomy or liver repair. Conclusion: Surgical resident experience on most trauma services is heavily weighted to nonoperative management, with a relatively low number of procedures, little experience with DPL, and highly variable experience with ultrasound. These data have serious implications for resident training and recruitment into the specialty.

The rod-pinch diode is operated successfully at peak voltages of 2.4–4.4 MV for peak electrical currents of 55–135 kA delivered to the diode. At 4 MV, tungsten anode rods of 1 or 2 mm diam produce on-axis doses at 1 m of 16 rad(Si) or 20 rad(Si), respectively. The on-axis source diameter based on the full width at half-maximum (FWHM) of the line-spread function (LSF) is 0.9±0.1 mm for a 1 mm diam rod and 1.4±0.1 mm for a 2 mm diam rod, independent of voltage. The LANL source diameter, determined from the modulation transfer function of the LSF, is nearly twice the FWHM. The measured rod-pinch current is reproduced with a diode model that includes ions and accounts for anode and cathode plasma expansion.

A laser shearing interferometer (LSI) was used to make spatially and temporally resolved measurements of the electron density profile in an imploding z pinch. Experiments were conducted on the 0.7-MA/250-ns Hawk machine, the 2.5-MA/100-ns ACE-4 machine, and the 3.8-MA/190-ns Double Eagle machine. Time and space resolved measurements of the current and plasma density are needed for better understanding of the implosion dynamics and stagnation physics of z pinches. The electron density profile can be obtained using an LSI. The LSI passes a short pulse, collimated laser beam across the imploding z pinch, which distorts the laser wavefront. the maximum wavefront distortion occurs where the density gradient is highest, such as across the current sheath. After passing through the pinch, the distorted wavefronts are split into two beams that are laterally displaced relative to one other. This shearing causes interference between these two wavefronts and produces an interferogram, from which the plasma density profiles are derived. In the experiments, a 150-ps laser pulse was split into two pulses with an interpulse delay of several tens. of nanoseconds. This pulse pair gave two snap shots of the electron density profiles during the 100-300-ns implosions. From these interferograms, electron densities and implosion velocities of the imploding plasmas were derived, the current sheath was observed, and the plasma ionization states, growth rates, and wavelengths of instabilities were estimated. The results motivate construction of an upgraded instrument with four or more frames and with an added laser polarimetry measurement (Faraday rotation) capability to obtain both electron and current profiles.

The rod-pinch diode is a cylindrical pinched-beam diode that provides an intense pulsed small-diameter bremsstrahlung source for radiography. For this work, the diode consists of a 1- to 6.4-mm-diameter anode rod that extends through the hole of an annular cathode. After exiting the cathode, wider anodes taper down to a 1 mm diameter. All of the anode rods then have a 1-mm-diameter tungsten tip that is usually tapered to a point. Rod-pinch diodes with anode rods of different materials, lengths, and diameters were powered by the Gamble II generator at peak voltages of 1.0 to 1.8 MV and peak currents of 30 to 60 kA. The radiation was characterized with temporally and spatially resolved X-ray diagnostics. Pinhole-camera images and time-resolved pin-diode measurements indicate that the radiation is emitted primarily from the vicinity of the rod tip. The dose measured with thermoluminescent detectors through a plexiglass transmission window ranges from 0.6 to 2.8 R at 1 m from the rod tip and the dose/charge scales faster than linearly with the diode voltage. The full-width at half-maximum (FWHM) of the radiation pulse is 30 to 50 ns. The size of the radiation source-is determined by measuring its edge spread function. The source diameter, defined here as the FWHM of the derivative of the edge spread function, decreases from 2 mm for a 6.4-mm-diameter rod to 1 mm or less for a 1-mm-diameter rod. Analysis suggests that the central portion of the radiation distribution at the source can be approximated by a uniformly radiating circular disc.

The name of the Committee on Nomenclature, Terminology & Symbols (NTS) may sound intimidating to some, but we have a simple mission: We focus on items that are important to the field of chemistry, to the work that chemists and chemical engineers do, and to the education of chemists and chemical engineers. Whether or not those speaking the language of science are members of the American Chemical Society, nomenclature, terminology, and symbols are an essential part of the conversation. Ensuring that we are correctly using the most current version of our language drives effective communication in the lab, in the classroom, in the boardroom, and with the general public. As chemists serving our profession, NTS seeks to keep ACS members and the ACS Council updated on important and pressing issues related to nomenclature, terminology, and symbols. To accomplish this task, NTS members and associates keep current with various governing bodies

Intense pulsed active detection (IPAD) is a promising technique for detecting fissile material to prevent the proliferation of special nuclear materials. With IPAD, fissions are induced in a brief, intense radiation burst and the resulting gamma ray or neutron signals are acquired during a short period of elevated signal-to-noise ratio. The 8 MV, 200 kA Mercury pulsed-power generator at the Naval Research Laboratory coupled to a high-power vacuum diode produces an intense 30 ns bremsstrahlung beam to study this approach. The work presented here reports on Mercury experiments designed to maximize the photofission yield in a depleted-uranium (DU) object in the bremsstrahlung far field by varying the anode-cathode (AK) diode gap spacing and by adding an inner-diameter-reducing insert in the outer conductor wall. An extensive suite of diagnostics was fielded to measure the bremsstrahlung beam and DU fission yield as functions of diode geometry. Delayed fission neutrons from the DU proved to be a valuable diagnostic for measuring bremsstrahlung photons above 5 MeV. The measurements are in broad agreement with particle-in-cell and Monte Carlo simulations of electron dynamics and radiation transport. These show that with increasing AK gap, electron losses to the insert and outer conductor wall increase and that the electron angles impacting the bremsstrahlung converter approach normal incidence. The diode conditions for maximum fission yield occur when the gap is large enough to produce electron angles close to normal, yet small enough to limit electron losses.

The rod-pinch diode consists of an annular cathode and a small-diameter anode rod that extends through the hole in the cathode. With high-atomic-number material at the tip of the anode rod, the diode provides a small-area, high-yield x-ray source for pulsed radiography. The diode is operated in positive polarity at peak voltages of 1 to 2 MV with peak total electrical currents of 30–70 kA. Anode rod diameters as small as 0.5 mm are used. When electrode plasma motion is properly included, analysis shows that the diode impedance is determined by space-charge-limited current scaling at low voltage and self-magnetically limited critical current scaling at high voltage. As the current approaches the critical current, the electron beam pinches. When anode plasma forms and ions are produced, a strong pinch occurs at the tip of the rod with current densities exceeding 106 A/cm2. Under these conditions, pinch propagation speeds as high as 0.8 cm/ns are observed along a rod extending well beyond the cathode. Even f...

Objectives: This article reviews the history of the measurement of unwanted and unintended pregnancy in fertility surveys in the United States. These concepts were developed in order to help explain trends and differences in birth rates in the United States. Background: Unwanted fertility was first measured systematically in a survey in Indianapolis in 1941. The first national surveys to measure the concept of unwanted fertility were the 1955 and 1960 Growth of American Families Studies. All three of these surveys were limited to married women. In the 1965 National Fertility Survey, the concept of mistimed births was introduced. The 1973, 1976, 1982, and 1988 National Survey of Family Growth (NSFG) continued to measure trends in unwanted and mistimed fertility, while expanding the population interviewed, from currently married to all marital statuses. The 1993 and 2001 NSFGs have enriched the data on wantedness with new measures of ambivalence and the strength of feelings about having children. Conclusion: Measures of unwanted fertility, while imperfect, have been useful and will continue to be improved in the future.

Introduction The management and removal of thoracostomy tubes for trauma-related hemothorax and pneumothorax is controversial. General recommendations exist; however, institutional data related to an algorithmic approach has not been well described. The difficulty in establishing an algorithm centers about individualized patients’ needs for subsequent management after thoracostomy tube placement. In our institution, we use the same protocol for all trauma patients who receive a thoracostomy tube with minimal complications. Purpose To present the clinical outcomes of patients who required a tube thoracostomy for traumatic injury and were managed by an institutional protocol. Methods A retrospective chart review of 313 trauma patients at a single level I trauma institution from January 2008 through June 2012 was conducted. Inclusion criteria were patient age ≥ 18 years, involvement in a trauma, and requirement of a thoracostomy tube. The patients’ charts were reviewed for demographic data, injury severity score (ISS), length of stay (LOS), and chest-tube specific data. Thoracostomy tube complications were defined as persistent air leak, persistent pneumothorax, recurrent pneumothorax, and clotting of thoracostomy tube. The patients were managed per our institutional algorithm. Descriptive statistics were performed. Results Most of the patients who required a thoracostomy tube had blunt-related traumas (271/313; 86.6%), while 42 patients (13.4%) sustained penetrating injuries. There were 215 (68.7%) male patients. The average age at time of injury was 45.7 ± 21.1 years and the mean ISS was 24.9 ± 15.9 (mean ± SD). Elevated alcohol levels were found in 65 of the 247 patients who were tested upon admission (26.3%). Overall, 15 patients (4.8%) developed a thoracostomy tube related complication: persistent air leak in six patients, persistent pneumothorax in six patients, recurrent pneumothorax in two patients, and clotted thoracostomy tube in one patient. The average LOS was 10.4 ± 8.4 days, and the mean length of thoracostomy tube placement was 5.9 ± 4.3 days. Conclusions Our algorithmic thoracostomy tube management protocol resulted in a complication rate of 4.8%. By managing thoracostomy tubes in a systematic manner, our patients have improved outcomes following placement and removal compared to other studies.

For many applications, control and manipulation of the electron orbits in a high-current electron beam is desirable. This is especially true when a weakly-self-pinched, multi-MV electron-beam is used to make bremsstrahlung radiation. In this case, the radiation pattern is highly peaked along the direction that the electron beam makes when it strikes the x-ray target. Therefore, to maximize the number of photons in the forward direction, it is desirable that the electrons strike the x-ray target as close to normal with as little spread in the beam angles as possible. In this paper, a method for controlling the macroscopic angle of a high-power electron beam using a post-diode magnetic-field structure is presented. The idea is to extract the electron beam into a vacuum cavity through a thin, low-mass foil where a portion of the return-current flows through a central post. The amount of current that flows through the central post and therefore the amount of beam straightening is controlled by inductively splitting the return current so that a portion of it returns through the central post and a portion returns outside the beam. By adjusting the balance between these two currents one can alter the electron orbits and achieve a wide range of angles that the electron beam makes with the target without the need for plasma or an external pulser.1 Particle-in-cell simulations have been performed to determine the parameters required to straighten an 8-MV, 200-kA, 23-cm-diameter hollow electron beam with an inward 20° macroscopic (average) angle so that it approaches the x-ray target at normal incidence. The simulations show an increase in the forward photon spectrum by up to a factor of 3. Experiments with similar beam parameters using the Mercury Inductive-Voltage Adder at the Naval Research Laboratory have shown an increase of a factor of two in the forward dose using this technique and are in good qualitative agreement with the simulations. Additional simulations and experiments are planned to optimize the forward dose and will be reported on during this talk.

There is ongoing interest in the use of an intense bremsstrahlung pulse to induce photofission in fissionable material.1, 2 To optimize the radiation for inducing fissions in the forward direction, electrons should approach normal incidence and their charge on the anode converter should be maximum. Here, these are optimized on the 8-MeV, 200-kA, 50-ns Mercury inductive voltage adder3 by varying the diode AK gap between 23 and 43 cm and adding an ID-reducing insert in the outer-conductor wall.2 Current monitors at the anode determine the load-region current fraction reaching the converter. TLDs and an x-ray pinhole camera measure the angular and radial x-ray dose distributions4, and 3 He detectors measure fissions induced in a 30×30×2.5-cm3 depleted uranium (DU) plate. Measurements are in broad agreement with LSP/ITS simulations of the electron dynamics and radiation transport. Current traces show that electron losses to the insert and outer-conductor wall increase with AK gap, confirming LSP predictions and pinhole camera measurements. With increasing AK gap, measured angular dose distributions narrow, on-axis dose and DU fission-neutrons increase, indicating that electron angles are approaching the converter normal. With the 43-cm gap, axial dose and fission neutrons decrease. For 40-cm gaps or larger, LSP electron impact angles on the converter are within 5 degrees of normal. For 8-MeV electrons, x-ray divergence does not narrow significantly for smaller electron angles. However, electron losses to the insert and wall continue to increase for larger gaps, explaining reduced performance at 43 cm. Bremsstrahlung produced by these electrons at large radius is collimated out of the x-ray beam reaching the DU. If the current lost to the insert and walls could reach the converter, LSP/ITS predicts a fission yield 1.75-times higher than that achieved with a 40-cm gap. Though wall losses with a 23-cm gap are small, the predicted 20-deg electron impact angles produce only about 1/3 of the on-axis fissions of the 40-cm gap. Therefore, research has begun to modify such smaller-gap diodes to magnetically steer electrons to converter impact angles closer to the normal.5

Summary form only given. An intense bremsstrahlung x-ray pulse is generated by the 8-MeV, 200-kA, 50-ns Mercury inductive voltage adder.1 A study of the diode configuration was undertaken to optimize the forward-directed radiation. To this end, the diode AK gap was varied between 23 and 43 cm and an ID-reducing insert in the vacuum chamber wall was added to adjust the incidence angle and the electron charge at the tantalum anode converter.2. Anode current monitors measure the portion of load-region current reaching the converter. Arrays of CaF2 TLDs, x-ray pin diodes and an x-ray pinhole camera are used to measure the x-ray dose distributions. Anode current data are presented which show that electron losses to the insert and to the outer-conductor wall increase with AK gap, in agreement with pinhole camera measurements. Pin diode signals are analyzed to determine beam dynamics during the pulse. TLD data are presented which show that, as the AK gap increases, the angular dose distribution narrows and that the on-axis dose increases, until the 43-cm AK gap configuration. Here, axial dose decreases as electron losses to the insert and vacuum chamber wall override any further benefit due to smaller incidence angle for electrons striking the anode. Bremsstrahlung produced by electrons at large radius impacting the walls is removed from the x-ray beam by a thick steel collimator. Though wall losses with a small, 23-cm gap are low, LSP/ITS simulations predict large electron impact angles, which would reduce the on-axis dose downstream of the diode. Research has begun to modify such smaller-gap diodes to magnetically steer electrons to converter impact angles closer to the normal3.

Introduction Performance improvement driven by the review of surgical morbidity and mortality is often limited to critiques of individual cases with a focus on individual errors. Little attention has been given to an analysis of why a decision seemed right at the time or to lower-level root causes. The application of scientific performance improvement has the potential to bring to light deeper levels of understanding of surgical decision-making, care processes, and physician psychology. Methods A comprehensive retrospective chart review of previously discussed morbidity and mortality cases was performed with an attempt to identify areas where we could better understand or influence behavior or systems. We avoided focusing on traditional sources of human error such as lapses of vigilance or memory. An iterative process was used to refine the practical areas for possible intervention. Definitions were then created for the major categories and subcategories. Results Of a sample of 152 presented cases, the root cause for 96 (63%) patient-related events was identified as uni-factorial in origin, with 51 (34%) cases strictly related to patient disease with no other contributing causes. Fifty-six cases (37%) had multiple causes. The remaining 101 cases (66%) were categorized into two areas where the ability to influence outcomes appeared possible. Technical issues were found in 27 (18%) of these cases and 74 (74%) were related to disorganized care problems. Of the 74 cases identified with disorganized care, 42 (42%) were related to failures in critical thinking, 18 (18%) to undisciplined treatment strategies, 8 (8%) to structural failures, and 6 (6%) were related to failures in situational awareness. Conclusions On a comprehensive review of cases presented at the morbidity and mortality conference, disorganized care played a large role in the cases presented and may have implications for future curriculum changes. The failure to think critically, to deliver disciplined treatment strategies, to recognize structural failures, and to achieve situational awareness contributed to the morbidities and mortalities. Future research may determine if focused training in these areas improves patient outcomes.

A high-impedance, small spot size diode for flash radiography has been successfully tested on a 2.3-MV generator. The generator is an L-3 Communications, Pulse Sciences Division, Pulserad 43703B, the largest in a series of generators originally called Febetron. These generators are normally used with long-life, larger diameter anodes in a sealed glass envelope. Previous work with the 1-MV Pulserad 43710A generator has demonstrated that the sealed tube can be replaced with a stacked ring insulator and the large anode replaced with a small, 1-mm diameter anode in order to achieve a much smaller spot size for single shot use.[1][2] Recently, the cathode design for this retrofitted diode has been improved for optimal performance.[3]

In intense, pulsed active detection, a single, intense pulse of radiation is used to induce photofission in fissionable material, increasing its detectability. The Mercury pulsed-power generator was converted to positive polarity (+3.7 MV, 325 kA, 50-ns FWHM) to drive an intense, pulsed radiation source based on the FIGARO active detection concept. The probing radiation source consisted of an ion-beam diode and a thick PTFE (Teflon) converter where 6–7 MeV γ-rays were produced via the 19F(p,αγ)16O reaction. A suite of radiation detectors was used both to detect the presence of irradiated fissionable material and to characterize the probing radiation source. Four types of detectors were used for the source characterization. Thermoluminescent dosimeters were used to measure the angular distribution of the dose associated with x-rays and γ-rays from the ion-beam diode. Plastic scintillator-photodiode detectors were used to characterize the time dependence of this dose. A plastic scintillator-photomultiplier detector was used to monitor the γ-ray intensity of the probing radiation source and to monitor changes in the production of background neutrons by the diode and PTFE converter. A set of rhodium foil activation counters was used to measure the absolute yield of these background neutrons. Two types of detectors with comparable sensitivities were used to measure delayed neutrons resulting from photofission: 3He proportional counters and a 6Li-loaded-glass-scintillator detector. The neutron detection rate from each detector following the probing radiation pulse was over 100 times higher with depleted uranium present than with lead.

The SATURN pulsed-power machine is normally operated in negative polarity using up to 3 cathodes and 4 anodes to drive three electron-beam diodes in parallel. A large-area, reflex triode for