Azimuthal Drive Asymmetry in Inertial Confinement Fusion Implosions on the National Ignition Facility

Data from nuclear diagnostics present correlated signatures of azimuthal implosion asymmetry in recent indirect-drive inertial confinement fusion (ICF) implosion campaigns performed at the National Ignition Facility (NIF). The mean hot-spot velocity, inferred from the Doppler shift of 14 MeV neutrons produced by deuterium-tritium (DT) fusion, is systematically directed toward one azimuthal half of the NIF target chamber, centered on ϕ≈70°. Areal density (ρR) asymmetry of the converged DT fuel, inferred from nuclear activation diagnostics, presents a minimum ρR in the same direction as the hot-spot velocity and with ΔρR amplitude correlated with velocity magnitude. These two correlated observations, which are seen in all recent campaigns with cryogenic layers of DT fuel, are a known signature of asymmetry in the fuel convergence, implying a systematic azimuthal drive asymmetry across a wide range of shot and target configurations. The direction of the implied radiation asymmetry is observed to cluster toward the hohlraum diagnostic windows. This low-mode asymmetry degrades hot-spot conditions at peak convergence and limits implosion performance and yield.

The Elements of British Technological Competitiveness

In this election year of 1987 the state of Britain's technology has remained high on the political agenda. Following the critical report from the House of Lords on civil research and development (1986), the government recently announced changes in its machinery and priorities and expressed concern about British industry's (lack of) funding of R and D compared to the main sources of foreign competition (see HM Government, 1987).

Comparison of perinatal outcomes between spontaneous vs. commissioned cycles in gestational carriers for single and same-sex male intended parents

PURPOSE

To determine whether gestational carrier (GC) in vitro fertilization (IVF) cycles (commissioned cycles) for same-sex or single male intended parents have an increased incidence of adverse perinatal outcomes compared with spontaneous cycles in the same GCs.

DESIGN

GC singleton pregnancies were identified from a database of 895 commissioned cycles from a large fertility center. Of these, 78 commissioned cycles met inclusion and exclusion criteria and were compared with 71 spontaneous cycles by the same GCs. The primary outcome was the composite score for adverse perinatal outcomes. Secondary outcomes included mode of delivery, birthweight, and gestational age. Chi-square test of association and Mann-Whitney U tests were used to compare categorical and continuous variables between the cohorts, respectively. Logistic and linear regressions controlling for GC age were constructed to determine the influence of GC cycle type on adverse perinatal outcomes.

RESULTS

Commissioned cycles were significantly associated with adverse perinatal outcomes (25.6% vs. 9.9%; p = 0.02) and lower average gestational age (38.7 ± 1.5 vs. 39.4 ± 0.9; p < 0.001) compared with spontaneous cycles. Commissioned cycle increased the likelihood of adverse perinatal outcomes (OR 3.3; p = 0.03) and was a significant independent predictor of a lower average gestational age (β = 0.897; p < 0.001). There were no significant differences in the incidence of vaginal deliveries or cesarean sections between commissioned and spontaneous cycles.

CONCLUSIONS

Commissioned cycles confer a greater incidence of composite perinatal complications and were independently associated with a lower average gestational age when compared with spontaneous pregnancies carried by the same GC despite a confirmed healthy uterine environment, sperm samples, and donor oocytes.

Determination of Retinyl Palmitate (Vitamin A) in Fortified Fluid Milk by Liquid Chromatography: Collaborative Study

A liquid chromatographic (LC) method was developed for fast and simple measurement of retinyl palmitate (vitamin A) in fortified milk. Retinyl acetate internal standard was added to a test portion of milk followed by extraction into hexane. The hexane extract was analyzed by LC using a normal-phase silica gel column equilibrated with mobile phase (conditioned hexane–isopropanol, 99.85 + 0.15, v/v) about 1 h before injections. The retinyl palmitate concentration was calculated by using a relative response factor determined with calibration standards. In the collaborative study, 11 laboratories analyzed 13 pairs of fluid milk materials in blind duplicate. Twelve of the materials were composed of skim milk (&lt;0.5% fat), 1% fat milk, 2% fat milk, and 1% fat chocolate milk. Each material was fortified at 3 concentrations of retinyl palmitate of approximately 581 μg/L (1000 IU/qt), 1163 μg/L (2000 IU/qt), and 2236 μg/L (4000 IU/qt). The 13th material, unfortified skim milk, served as a matrix blank. Repeatability standard deviations (RSDr) without outliers ranged from 1.5 to 5.7% and reproducibility standard deviations (RSDR) without outliers ranged from 5.0 to 22.7%. cis-Isomers co-eluted with the predominant trans-retinyl palmitate isomer and were included in the results reported by all the collaborative laboratories. Endogenous long-chain esters from milk fat were also measured with the retinyl palmitate additive. The Study Director recommends that this method for determination of retinyl palmitate in fluid milk by LC be adopted First Action.

Validation of an Immunoassay for Detection and Quantitation of a Genetically Modified Soybean in Food and Food Fractions Using Reference Materials: Interlaboratory Study

An immunoassay for detection of a specific genetically modified soybean (Roundup-Ready®) was validated on dried soybean powder in an interlaboratory study. Different percentages of genetically modified soybeans in nonmodified soybean matrix were evaluated in a blind study. Thirty-eight laboratories from 13 countries participated. The immunoassay was evaluated for 2 endpoints: (1) To give a semiquantitative result, i.e., determination of a given sample above or below a given threshold, or (2) to compute a quantitative result, i.e., percentage of genetically modified soybeans in the sample. Semiquantitative results showed that a given sample which contained &lt;2% genetically modified soybeans was identified as below 2% with a 99% confidence level. Quantitative use of the assay resulted in a repeatability (r) and reproducibility (R) that were computed to be RSDr = 7% and RSDR = 10%, respectively, for a sample containing 2% genetically modified soybeans. Application of this method depends on availability of appropriate reference materials for a specific food matrix. Only matrix-matched reference materials can be used for analysis of food or food fractions.

Perceptions of e-professionalism among dental students: a UK dental school study

Introduction

The social media activity of some healthcare students has created doubt about their ability to uphold and defend the ethical principles of healthcare in their online behaviours. A lot of research has been conducted on the online behaviours of medical and allied health professional students, however, less has been undertaken on dental students.

Aims

The aim was to determine whether students were aware of the guidelines set by the General Dental Council (GDC) regarding social media and whether they believed they were being professional in their online activities.

Methods and materials

Eighty-eight dental students (46 from year 2; 42 from year 4) at one UK dental school completed a questionnaire study examining their attitude towards and perceptions of e-professionalism.

Results

The results show that most students were heavy users of social media with an awareness of social media guidelines set out by the GDC. However, student responses to various e-professionalism scenarios reveals disagreement on whether posts referring to alcohol and work colleagues were deemed unprofessional.

Conclusion

Student perceptions of and attitudes towards e-professionalism is complicated and contradictory. More research will need to be undertaken to explore how we can inculcate e-professional values and behaviours in dental professionalism teaching.

1424The diagnosis of non-adherence in hypertension using a urine biochemical screen is unaffected by drug pharmacokinetics

Introduction

Suboptimal drug adherence in hypertension is pandemic and traditional diagnostic tools to detect non-adherence have lacked accuracy and robustness. The inability to identify non-adherence has therefore driven the development of biochemical drug screening by liquid chromatography tandem mass spectrometry (LC- MS/MS) in urine and blood, which are the most accurate metrics presently available. Urinary antihypertensive testing is evidenced to improve non-adherence rates, significantly decrease blood pressure after physician intervention, and be cost effective. The European Society of Cardiology (ESC) and European Society of Hypertension (ESH) 2018 guidelines have recommended the use of biochemical testing for non-adherence diagnosis. However, it has been argued that the variable pharmacokinetic parameters of the medication (such as their half-lives and clearance rates) may affect the detection of medications in urine and hence the determination of adherence. We hypothesized that pharmacokinetic parameters do not affect the detection of antihypertensive medications in urine.

Aim

This study compared the pharmacokinetic parameters of the most commonly prescribed antihypertensive medications against their detection in urine by LC-MS/MS.

Methods

Results of urinary drug screens from 463 hypertensive patients (total prescribed medications N=1709) were collated. An adherence score termed as the C score (number of detected vs. prescribed medication) was generated for each of the 27 common antihypertensive medications. Pharmacokinetic parameters such as bioavailability, plasma concentration, volume of distribution, half-life, plasma clearance and urinary excretion values for each drug were obtained from published literature. Partial linear correlation was conducted between the C score of all the medications and each pharmacokinetic parameter studied.

Results

40% of patients were non-adherent. The average number of prescribed medications was high (N=3.7, SD: 1.5), and the average number of drugs detected was lower (N=2.5, SD: 1.6). Amlodipine was the most prescribed (N=224), and clonidine was the least (N=10). The half-lives ranged from 0.87 to 39 hours for bumetanide and amlodipine respectively. The urinary excretion percentage varied from <1% for nifedipine, and 94% for benfroflumethiazide. No significant correlation was found between any drug C score and their respective pharmacokinetic variables such as the medication half-lives (figure1).

Half-life versus adherence score

Conclusion

This study reports no significant correlation between drug pharmacokinetics and adherence. To the best of our knowledge this is the first study of its kind. Urinary biochemical testing by LC-MS/MS for non-adherence remains a valid tool for diagnosis although further detailed pharmacokinetic studies are needed to confirm this finding.

Acknowledgement/Funding

None

A checklist for trauma quality improvement meetings: A process improvement study

BACKGROUND

Each year approximately five million people die from injuries. In countries where systems of trauma care have been introduced, death and disability have decreased. A major component of developed trauma systems is a trauma quality improvement (TQI) program and trauma quality improvement meeting (TQIM). Effective TQIMs improve trauma care by identifying and fixing problems. But globally, TQIMs are absent or unstructured in most hospitals providing trauma care. The aim of this study was to implement and evaluate a checklist for a structured TQIM.

METHODS

This project was conducted as a prospective before-and-after study in four major trauma centres in India. The intervention was the introduction of a structured TQIM using a checklist, introduced with a workshop. This workshop was based on the World Health Organization (WHO) TQI Programs short course and resources, plus the developed TQIM checklist. Pre- and post-intervention data collection occurred at all meetings in which cases of trauma death were discussed. The primary outcome was TQIM Checklist compliance, defined by the discussion of, and agreement upon each of the following: preventability of death, identification of opportunities to improve care and corrective actions and a plan for closing the loop.

RESULTS

There were 34 meetings in each phase, with 99 cases brought to the pre-intervention phase and 125 cases brought to the post-intervention phase. There was an increase in the proportion of cases brought to the meeting for which preventability of death was discussed (from 94% to 100%, p = 0.007) and agreed (from 7 to 19%, OR 3.7; 95% CI:1.4-9.4, p = 0.004) and for which a plan for closing the loop was discussed (from 2% to 18%, OR 10.9; 95% CI:2.5-47.6, p < 0.001) and agreed (from 2% to 18%, OR 10.9; 95% CI:2.5-47.6, p < 0.001).

CONCLUSION

This study developed, implemented and evaluated a TQIM Checklist for improving TQIM processes. The introduction of a TQIM Checklist, with training, into four Indian trauma centres, led to more structured TQIMs, including increased discussion and agreement on preventability of death and plans for loop closure. A TQIM Checklist should be considered for all centres managing trauma patients.

Distal Transradial Access in the Anatomic Snuffbox for Diagnostic Cerebral Angiography

The aim of this study was to describe the feasibility, technique, and safety of distal transradial access in the anatomic snuffbox for diagnostic cerebral angiography. A retrospective review of diagnostic cerebral angiograms obtained during a 6-month period with distal transradial access was performed. Thirty-four successful procedures were performed via distal transradial access. There were 4 failed attempts. This single-center experience using distal transradial access suggests that this technique is safe and effective.

Metastasis of squamous cell carcinoma of the head and neck to the thyroid: a single institution's experience with a review of relevant publications

The thyroid gland is a rare site of metastasis, and in particular of those of squamous cell carcinoma (SCC) from the head and neck region. We have reviewed the aetiology, pathogenesis, clinical characteristics, radiological features, immunohistochemical profile, prognosis, and management of metastatic SCC from the head and neck region to the thyroid, and searched current publications on the Medline, Embase, and Cochrane databases using the following keywords: "SCC of thyroid", "secondary SCC of thyroid", and "metastasis to the thyroid", for papers published during the last 33 years (April 1984 to October 2017).We found a total of 19 papers that reported a total of 32 cases that were relevant. Four further cases were discovered as an incidental finding on follow-up positron emission tomographic/computed tomographic scans with magnetic resonance imaging of the head and neck at our hospital, which were confirmed with an ultrasound-guided core needle biopsy followed by immunohistochemical examination. For patients who are doing well, whose disease is controlled at the primary site, and who have no evidence of distant metastatic disease, total thyroidectomy could be considered followed by adjuvant radiation or chemoradiotherapy, depending on the presence of intermediate or high-risk features on pathological examination and previous history of radiation. This may help to control the disease and avoid local morbidity.

Lower serum adiponectin level is associated with lipodystrophy among HIV-infected men in the Study to Understand the Natural History of HIV/AIDS in the Era of Effective Therapy (SUN) study

OBJECTIVES

Adiponectin levels are inversely related to cardiovascular risk and are low in diabetics and obese persons. We examined the association between adiponectin concentration and HIV-associated lipodystrophy, which remains unclear.

METHODS

The Study to Understand the Natural History of HIV/AIDS in the Era of Effective Therapy (SUN) was a prospective cohort study of HIV-infected adults conducted in four US cities. Lean body and fat masses were assessed using dual-energy X-ray absorptiometry scans. Using baseline data from 2004 to 2006, we defined lipodystrophy using a sex-specific fat mass ratio and performed cross-sectional analyses of associated risks using multivariable logistic regression.

RESULTS

Among 440 male participants (median age 42 years; 68% non-Hispanic white; 88% prescribed combination antiretroviral therapy; median CD4 lymphocyte count 468 cells/μL; 76% with viral load < 400 HIV-1 RNA copies/mL; 5% diabetic; median body mass index 25 kg/m² ), median concentrations of leptin and adiponectin were 3.04 ng/L [interquartile range (IQR) 1.77-5.43 ng/L] and 8005 μg/mL (IQR 4950-11 935 μg/mL), respectively. The prevalence of lipodystrophy was 14%. Lipodystrophy was significantly associated with increasing age [prevalence ratio (PR) 1.50; 95% confidence interval (CI) 1.10-2.06, per 10 years], adiponectin < 8005 μg/mL (PR 5.02; 95% CI 2.53-9.95), ever stavudine use (PR 2.26; 95% CI 1.36-3.75), CD4 cell count > 500 cells/μL (PR 2.59; 95% CI 1.46-4.61), viral load < 400 copies/mL (PR 3.98; 95% CI 1.25-12.6), highly sensitive C-reactive protein < 1.61 mg/L (PR 1.91; 95% CI 1.11-3.28) and smoking (PR 0.42; 95% CI 0.22-0.78).

CONCLUSIONS

Among men in this HIV-infected cohort, the prevalence of lipodystrophy was similar to previous estimates for persons living with HIV, and was associated with lower adiponectin levels, potentially indicating increased cardiovascular disease risk.

Comparative analysis of microleakage of temporary filling materials used for multivisit endodontic treatment sessions in primary teeth: an in vitro study

PURPOSE

Coronal leakage is an important factor contributing to the failure of endodontic treatment. The use of an efficient temporary restoration between sessions of multiple-visit pulpectomies is irrefutable. Two cements have long been used in endodontics-IRM, which is a reinforced zinc oxide cement and Cavit G, a calcium sulphate based cement. The aim of this study was to compare the microleakage of nano silver containing UDMA-based cements with routinely used zinc oxide and calcium sulphate-based temporary cements in primary teeth.

METHODS

Standardized access cavities of 3 × 3 mm were prepared in the sixty caries-free primary molars. The teeth were divided randomly into four groups of 14 teeth each-Group I: IRM, Group II: Cavit G, Group III: Orafil-G and Group IV: Dia-Temp. Temporary restorative materials were applied according to the manufacturer's instructions. The teeth were subjected to thermocycling and then immersed in 0.5% basic fuchsin for 24 h. The specimens were sectioned and evaluated under a digital microscope at 20× magnification and were scored for microleakage. The collected data were tabulated and subjected to statistical analysis.

RESULTS

Dia-Temp presented the least microleakage values. The highest score for microleakage was shown by IRM followed by Orafil-G and Cavit-G. There was a significant difference between IRM and Diatemp groups (p value = 0.009), and among Orafil G and Diatemp groups (p value = 0.025).

CONCLUSION

Among the four materials tested, Dia-Temp exhibited the best sealing ability and its use is recommended in between sessions of endodontic treatment in primary teeth.

Using 17-OHP as Serum Biomarker to Monitor Therapy in Patients With Hypogonadotropic Hypogonadism

Exogenous testosterone administration decreases intratesticular testosterone (ITT) significantly, an essential hormone for spermatogenesis. Therefore, treatment of patients with hypogonadotropic hypogonadism (HH) who desire infertility can be challenging. These patients are treated with recombinant follicle-stimulating hormone (FSH), clomiphene citrate, and human chorionic gonadotropin (hCG) to increase their ITT. However, there is no approved serum biomarker for ITT and it can only be measured via invasive testicular biopsy or aspiration. Previous authors have speculated that serum 17-hydroxyprogestrone (17-OHP) can be used as serum biomarker for ITT. In our case report, we demonstrate increase in 17-OHP associated with spermatogenesis after commencing treatment for infertility in patient with HH.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.