Measurement of Dark Ice-Ablator Mix in Inertial Confinement Fusion.

We present measurements of ice-ablator mix at stagnation of inertially confined, cryogenically layered capsule implosions. An ice layer thickness scan with layers significantly thinner than used in ignition experiments enables us to investigate mix near the inner ablator interface. Our experiments reveal for the first time that the majority of atomically mixed ablator material is "dark" mix. It is seeded by the ice-ablator interface instability and located in the relatively cooler, denser region of the fuel assembly surrounding the fusion hot spot. The amount of dark mix is an important quantity as it is thought to affect both fusion fuel compression and burn propagation when it turns into hot mix as the burn wave propagates through the initially colder fuel region surrounding an igniting hot spot. We demonstrate a significant reduction in ice-ablator mix in the hot-spot boundary region when we increase the initial ice layer thickness.

Record Energetics for an Inertial Fusion Implosion at NIF.

Inertial confinement fusion seeks to create burning plasma conditions in a spherical capsule implosion, which requires efficiently absorbing the driver energy in the capsule, transferring that energy into kinetic energy of the imploding DT fuel and then into internal energy of the fuel at stagnation. We report new implosions conducted on the National Ignition Facility (NIF) with several improvements on recent work [Phys. Rev. Lett. 120, 245003 (2018)PRLTAO0031-900710.1103/PhysRevLett.120.245003; Phys. Rev. E 102, 023210 (2020)PRESCM2470-004510.1103/PhysRevE.102.023210]: larger capsules, thicker fuel layers to mitigate fuel-ablator mix, and new symmetry control via cross-beam energy transfer; at modest velocities, these experiments achieve record values for the implosion energetics figures of merit as well as fusion yield for a NIF experiment.

Evidence of Three-Dimensional Asymmetries Seeded by High-Density Carbon-Ablator Nonuniformity in Experiments at the National Ignition Facility.

Inertial confinement fusion implosions must achieve high in-flight shell velocity, sufficient energy coupling between the hot spot and imploding shell, and high areal density (ρR=∫ρdr) at stagnation. Asymmetries in ρR degrade the coupling of shell kinetic energy to the hot spot and reduce the confinement of that energy. We present the first evidence that nonuniformity in the ablator shell thickness (∼0.5% of the total thickness) in high-density carbon experiments is a significant cause for observed 3D ρR asymmetries at the National Ignition Facility. These shell-thickness nonuniformities have significantly impacted some recent experiments leading to ρR asymmetries on the order of ∼25% of the average ρR and hot spot velocities of ∼100 km/s. This work reveals the origin of a significant implosion performance degradation in ignition experiments and places stringent new requirements on capsule thickness metrology and symmetry.

Female In-Class Participation and Performance Increase with More Female Peers and/or a Female Instructor in Life Sciences Courses.

As we strive to make science education more inclusive, more research is needed to fully understand gender gaps in academic performance and in-class participation in the life sciences. Studies suggest that male voices dominate introductory biology courses, but no studies have been done on upper-level courses. Results on achievement gender gaps in biology vary and often conflict, and no studies have been done on the correlation between participation and academic performance gaps. We observed 34 life sciences courses at all levels at a large private university. Overall, males were more likely to participate than their female peers, but these gender gaps varied from class to class. Females participated more in classes in which the instructor called on most hands that were raised or in classes with more females in attendance. Performance gender gaps also varied by classroom, but female final course grades were as much as 0.2 SD higher in classes with a female instructor and/or a female student majority. Gender gaps in participation and final course grades were positively correlated, but this could be solely because female students are more likely to both participate more and earn higher grades in classes with many females in attendance.

Point Prevalence of Adult Intestinal Failure in Republic Of Ireland.

Parenteral Nutrition (PN) is a life-saving treatment used for patients with Intestinal Failure (IF). PN is complex and demands highly specialised care to avoid serious complications in the home setting. All tertiary centres in the Republic of Ireland (ROI) were contacted to assess the prevalence of IF requiring PN and complications, over a one year period. Sixty-seven patients were treated across 15 centres: a period prevalence of 14.6 and 9.6 patients per million for long-term PN and home PN respectively. Three-quarters of patients experienced at least one major complication with 18% mortality rate over the study period. There were 2.86 admissions per HPN patient, each lasting mean 13.4 days. One-third experienced catheter-related infections. There was a reduced length of stay during emergency re-admissions in high volume centres (mean 31 v 43 days, p=0.17). The establishment of a National Centre for IF/HPN in ROI is integral to reducing PN-associated complications.

Fusion Energy Output Greater than the Kinetic Energy of an Imploding Shell at the National Ignition Facility.

A series of cryogenic, layered deuterium-tritium (DT) implosions have produced, for the first time, fusion energy output twice the peak kinetic energy of the imploding shell. These experiments at the National Ignition Facility utilized high density carbon ablators with a three-shock laser pulse (1.5 MJ in 7.5 ns) to irradiate low gas-filled (0.3 mg/cc of helium) bare depleted uranium hohlraums, resulting in a peak hohlraum radiative temperature ∼290 eV. The imploding shell, composed of the nonablated high density carbon and the DT cryogenic layer, is, thus, driven to velocity on the order of 380 km/s resulting in a peak kinetic energy of ∼21 kJ, which once stagnated produced a total DT neutron yield of 1.9×10^{16} (shot N170827) corresponding to an output fusion energy of 54 kJ. Time dependent low mode asymmetries that limited further progress of implosions have now been controlled, leading to an increased compression of the hot spot. It resulted in hot spot areal density (ρr∼0.3 g/cm^{2}) and stagnation pressure (∼360 Gbar) never before achieved in a laboratory experiment.

Learning Gains from a Recurring "Teach and Question" Homework Assignment in a General Biology Course: Using Reciprocal Peer Tutoring Outside Class.

Providing students with one-on-one interaction with instructors is a big challenge in large courses. One solution is to have students interact with their peers during class. Reciprocal peer tutoring (RPT) is a more involved interaction that requires peers to alternate the roles of "teacher" and "student." Theoretically, advantages for peer tutoring include the verbalization and questioning of information and the scaffolded exploration of material through social and cognitive interaction. Studies on RPT vary in their execution, but most require elaborate planning and take up valuable class time. We tested the effectiveness of a "teach and question" (TQ) assignment that required student pairs to engage in RPT regularly outside class. A quasi-experimental design was implemented: one section of a general biology course completed TQ assignments, while another section completed a substitute assignment requiring individuals to review course material. The TQ section outperformed the other section by ∼6% on exams. Session recordings were coded to investigate correlation between TQ quality and student performance. Asking more questions was the characteristic that best predicted exam performance, and this was more predictive than most aspects of the course. We propose the TQ as an easy assignment to implement with large performance gains.

Publisher's Note: X-ray shadow imprint of hydrodynamic instabilities on the surface of inertial confinement fusion capsules by the fuel fill tube [Phys. Rev. E 95, 031204(R) (2017)].

This corrects the article DOI: 10.1103/PhysRevE.95.031204.

X-ray shadow imprint of hydrodynamic instabilities on the surface of inertial confinement fusion capsules by the fuel fill tube.

Measurements of hydrodynamic instability growth for a high-density carbon ablator for indirectly driven inertial confinement fusion implosions on the National Ignition Facility are reported. We observe significant unexpected features on the capsule surface created by shadows of the capsule fill tube, as illuminated by laser-irradiated x-ray spots on the hohlraum wall. These shadows increase the spatial size and shape of the fill tube perturbation in a way that can significantly degrade performance in layered implosions compared to previous expectations. The measurements were performed at a convergence ratio of ∼2 using in-flight x-ray radiography. The initial seed due to shadow imprint is estimated to be equivalent to ∼50-100 nm of solid ablator material. This discovery has prompted the need for a mitigation strategy for future inertial confinement fusion designs as proposed here.

Potential of Earlier Detection and Treatment of Disease-Related Malnutrition with Oral Nutrition Supplements to Release Acute Care Bed Capacity.

A recent systematic review and meta-analysis shows that appropriate use of oral nutrition supplements (ONS) in community patients is associated with a significant reduction in hospitalisations. Given higher use of acute care resource by malnourished versus normally nourished patients, this paper examines the potential to reduce bed utilisation by applying these results to Irish inpatient and malnutrition prevalence data. In 2013, adults admitted to hospital with medium or high malnutrition risk scores used an estimated 36% of adult acute inpatient bed days. Targeted use of ONS in community patients might reduce hospitalisation by 168,438 adult bed days per year, equivalent to 460 beds per day. This is particularly important, given high bed occupancy rates and twelve month daily averages of 254 patients on trolleys. Relevant stakeholders should consider strategies to ensure effective ONS use with a view to improving outcomes and reducing pressure on the acute care system.

11-interval PFG pulse sequence for improved measurement of fast velocities of fluids with high diffusivity in systems with short T2(∗).

Magnetic resonance (MR) was used to measure SF6 gas velocities in beds filled with particles of 1.1 mm and 0.5 mm in diameter. Four pulse sequences were tested: a traditional spin echo pulse sequence, the 9-interval and 13-interval pulse sequence of Cotts et al. (1989) and a newly developed 11-interval pulse sequence. All pulse sequences measured gas velocity accurately in the region above the particles at the highest velocities that could be achieved (up to 0.1 ms(-1)). The spin echo pulse sequence was unable to measure gas velocity accurately in the bed of particles, due to effects of background gradients, diffusivity and acceleration in flow around particles. The 9- and 13-interval pulse sequence measured gas velocity accurately at low flow rates through the particles (expected velocity <0.06 ms(-1)), but could not measure velocity accurately at higher flow rates. The newly developed 11-interval pulse sequence was more accurate than the 9- and 13-interval pulse sequences at higher flow rates, but for velocities in excess of 0.1 ms(-1) the measured velocity was lower than the expected velocity. The increased accuracy arose from the smaller echo time that the new pulse sequence enabled, reducing selective attenuation of signal from faster moving nuclei.

Complete procidentia: temporizing treatment with an obstetric balloon.

BACKGROUND: Pelvic organ incarceration resulting from complete uterovaginal prolapse is rare. Unique management and treatment of this condition are presented. CASE: A 66-year-old multigravid woman presented with increasing abdominal pain, 1-day history of urinary retention, and 30-day history of obstipation. She exhibited complete procidentia, and an attempt to reduce the prolapse immediately was unsuccessful. After fecal disimpaction in the operating room, an obstetric balloon was used for temporary reduction. CONCLUSION: Incarcerated complete procidentia is treated in a stepwise process, initially reducing the prolapse to relieve acute incarceration symptoms. Typically, reduction is accomplished with the aid of a pessary. However, because of this patient's condition, an obstetric balloon was used for temporary reduction to allow subsequent surgical treatment after tissue rest and medical stabilization. This method should be considered in similar situations.

Initial experience with a rapid access blackouts triage clinic.

Transient loss of consciousness (T-LOC), or blackout, is common in acute medicine. Clinical skills are not done well, with at least 74,000 patients misdiagnosed and mistreated for epilepsy in England alone. The aim of this study was to provide a rapid, structured assessment and an electrocardiogram (ECG) for patients with blackouts, aiming to identify high risk, reduce misdiagnoses, reduce hospital admission rates for low-risk patients, diagnose and treat where appropriate, and also provide onward specialist referral. The majority of patients had syncope, and very few had epilepsy. A high proportion had an abnormal ECG. A specialist-nurse-led rapid access blackouts triage clinic (RABTC) provided rapid effective triage for risk, a comprehensive assessment format, direct treatment for many patients, and otherwise a prompt appropriate onward referral. Rapid assessment through a RABTC reduced re-admissions with blackouts. Widespread use of the web-based blackouts tool could provide the NHS with a performance map. The U.K. has low rates of pacing compared to Western Europe, which RABTCs might help correct. The RABTC sits between first responders and specialist referral, providing clinical assessment and ECG in all cases, and referral where appropriate.

Circulating beta-carotene levels and type 2 diabetes-cause or effect?

AIMS/HYPOTHESIS: Circulating beta-carotene levels are inversely associated with risk of type 2 diabetes, but the causal direction of this association is not certain. In this study we used a Mendelian randomisation approach to provide evidence for or against the causal role of the antioxidant vitamin beta-carotene in type 2 diabetes. METHODS: We used a common polymorphism (rs6564851) near the BCMO1 gene, which is strongly associated with circulating beta-carotene levels (p = 2 x 10(-24)), with each G allele associated with a 0.27 standard deviation increase in levels. We used data from the InCHIANTI and Uppsala Longitudinal Study of Adult Men (ULSAM) studies to estimate the association between beta-carotene levels and type 2 diabetes. We next used a triangulation approach to estimate the expected effect of rs6564851 on type 2 diabetes risk and compared this with the observed effect using data from 4549 type 2 diabetes patients and 5579 controls from the Diabetes Genetics Replication And Meta-analysis (DIAGRAM) Consortium. RESULTS: A 0.27 standard deviation increase in beta-carotene levels was associated with an OR of 0.90 (95% CI 0.86-0.95) for type 2 diabetes in the InCHIANTI study. This association was similar to that of the ULSAM study (OR 0.90 [0.84-0.97]). In contrast, there was no association between rs6564851 and type 2 diabetes (OR 0.98 [0.93-1.04], p = 0.58); this effect size was also smaller than that expected, given the known associations between rs6564851 and beta-carotene levels, and the associations between beta-carotene levels and type 2 diabetes. CONCLUSIONS/INTERPRETATION: Our findings in this Mendelian randomisation study are in keeping with randomised controlled trials suggesting that beta-carotene is not causally protective against type 2 diabetes.

Investigation of ecological and environmental determinants for the presence of questing Ixodes ricinus (Acari: Ixodidae) on Gower, South Wales.

The spatial heterogeneity of questing Ixodes ricinus (L.) (Acari: Ixodidae) within endemic areas in Great Britain is well established. Their presence is acutely responsive to blood host availability and their ability to maintain water balance, which are in turn governed by a variety of ecological and environmental factors. This article details the findings of a 3-yr study on the Gower peninsula, south Wales, which investigated the contribution of such factors (both ground- and geographic information systems [GIS] -derived) for predicting the presence of questing I. ricinus (Q(P)), at a local scale. Statistically significant univariate associations were found between Q(P) and calcareous/ neutral grassland and heathland habitats, particularly those grazed by livestock, and various factors that intuitively promote tick survival. For example, topographical features, such as certain aspects, that reduce exposure to cold northerly winds and the hot midday sun, favored Q(P). Similarly, positive associations were found with substrata composed of less permeable soil types and less permeable superficial/bedrock geologies that promote a moist microhabitat and reduce the likelihood of desiccation. Q(P) was also higher in areas of high soil moisture. This study highlighted a number of GIS-derived data sets that could be applied in the development of local and national predictive maps for I. ricinus in Great Britain. An understanding of the influence of these factors on questing I. ricinus can aid targeted tick control programs and help to educate the public, and those occupationally exposed, in understanding likely I. ricinus prolific areas within an I. ricinus endemic region.

Beyond grasping: representation of action in human anterior intraparietal sulcus.

The fronto-parietal network has been implicated in the processing of multisensory information for motor control. Recent methodological advances with both fMRI and TMS provide the opportunity to dissect the functionality of this extensive network in humans and may identify distinct contributions of local neural populations within this circuit that are not only related to motor planning, but to goal oriented behavior as a whole. Herein, we review and make parallels between experiments in monkeys and humans on a broad array of motor as well as non-motor tasks in order to characterize the specific contribution of a region in the parietal lobe, the anterior intraparietal sulcus (aIPS). The intent of this article is to review: (1) the historical perspectives on the parietal lobe, particularly the aIPS; (2) extend and update these perspectives based on recent empirical data; and (3) discuss the potential implications of the revised functionality of the aIPS in relationship to complex goal oriented behavior and social interaction. Our contention is that aIPS is a critical node within a network involved in the higher order dynamic control of action, including representation of intended action goals. These findings may be important not only for guiding the design of future experiments investigating related issues but may also have valuable utility in other fields, such social neuroscience and biomedical engineering.

Enhancing cell survival of atrazine degrading Rhodococcus erythropolis NI86/21 cells encapsulated in alginate beads.

AIMS: To develop a method to produce beads with encapsulated Rhodococcus erythropolis NI86/21 with high cell density, extended shelf life, ease of handling and good atrazine degradation capabilities in both liquid and in agricultural soil. METHODS AND RESULTS: Our findings show that the supplementary recovery step in nutrient broth media shortly after cell encapsulation facilitates cell survival in both wet and dry beads upon extended storage at 4 degrees C. Air drying has little or no impact on encapsulated R. erythropolis cell's ability to degrade atrazine in liquid or soil. Bead storage for periods extending up to 12 months at 4 degrees C did not affect the capacity of R. erythropolis encapsulated cells to degrade atrazine in either BMN or nonsterile soil extracts. Bentonite-amended beads formulated with 1% skim milk and exposed to the supplementary growth step, outperformed all other bead formats. These beads provided adequate numbers of vigorous R. erythropolis cells in either liquid or soil media to degrade atrazine. CONCLUSIONS: Supplementary growth in nutrient broth media immediately following cell encapsulation greatly enhances R. erythropolis cells survival in both wet and dry beads upon extended storage at 4 degrees C. Wet and dried beads have similar capacity for atrazine degradation, and their usefulness and appeal in agronomic practise will only be known after bioassay evaluation and successful demonstration at field scale using incurred residues. SIGNIFICANCE AND IMPACT OF THE STUDY: R. erythropolis NI86/21 encapsulated cells have the potential to reduce residual atrazine in soil, thereby minimizing the likelihood of off-site transport to ground or river water and reduce the loss of crops because of phytotoxicity of residual herbicide. Owing to their ease of handling, storage and possible compatibilities with pre-existing mechanical equipment, dried bead formats are ideally suited for agricultural and remediational applications.

The regulatory alpha subunit of phosphorylase kinase may directly participate in the binding of glycogen phosphorylase.

The yeast two-hybrid screen has been used to identify potential regions of interaction of the largest regulatory subunit, alpha, of phosphorylase kinase (PhK) with two fragments of its protein substrate, glycogen phosphorylase b (Phb). One fragment, corresponding to residues 17-484 (PhbN'), contained the regulatory domain of the protein, but in missing the first 16 residues was devoid of the sole phosphorylation site of Phb, Ser14; the second fragment corresponded to residues 485-843 (PhbC) and contained the catalytic domain of Phb. Truncation fragments of the alpha subunit were screened for interactions against these two substrate fragments. PhbC was not found to interact with any alpha constructs; however, PhbN' interacted with a region of alpha (residues 864-1014) that is near the phosphorylatable region of that subunit. PhbN' was also screened for interactions against a variety of fragments of the catalytic gamma subunit of PhK; however, no interactions were detected, even with full-length gamma. Our results support the idea that amino acid residues proximal to the convertible serine of Phb are important for its specific interaction with the catalytic subunit of PhK, but that regions distinct from the convertible serine residue of Phb and from the catalytic domain of PhK may also be involved in the interaction of these two proteins.

A four-dimensional study of the aortic root dynamics.

OBJECTIVE: Although aortic root expansion has been well studied, its deformation and physiologic relevance remain controversial. Three-dimensional (3-D) sonomicrometry (200Hz) has made time-related 4-D study possible. METHODS: Fifteen sonomicrometric crystals were implanted into the aortic root of eight sheep at each base (three), commissures (three), sinuses of Valsalva (three), sinotubular junction (three), and ascending aorta (three). In this acute, open-chest model, the aortic root geometric deformations were time related to left ventricular and aortic pressures. RESULTS: During the cardiac cycle, aortic root volume increased by mean+/-1 standard error of the mean (SEM) 33.7+/-2.7%, with 36.7+/-3.3% occurring prior to ejection. Expansion started during isovolumic contraction at the base and commissures followed (after a delay) by the sinotubular junction. At the same time, ascending aorta area decreased (-2.6+/-0.4%). During the first third of ejection, the aortic root reached maximal expansion followed by a slow, then late rapid decrease in volume until mid-diastole. During end-diastole, the aortic root volume re-expanded by 11.3+/-2.4%, but with different dynamics at each area level. Although the base and commissural areas re-expanded, the sinotubular junction and ascending aorta areas kept decreasing. At end-diastole, the aortic root had a truncated cone shape (base area>commissures area by 51.6+/-2.0%). During systole, the root became more cylindrical (base area>commissures area by 39.2+/-2.5%) because most of the significant changes occurred at commissural level (63.7+/-3.6%). CONCLUSION: Aortic root expansion follows a precise chronology during systole and becomes more cylindrical - probably to maximize ejection. These findings might stimulate a more physiologic approach to aortic valve and aortic root surgical procedures.

Aortic and pulmonary root: are their dynamics similar?

OBJECTIVES: The long-term behavior of the pulmonary autograft in the aortic position (Ross procedure) remains uncertain. Using three-dimensional (3D) sonomicrometry (200 Hz) we compared the dynamics of the aortic and pulmonary roots. METHODS: Twenty-four crystals were implanted in each aortic (eight sheep) and pulmonary roots (six sheep) at: base (3 x 2), commissures (3 x 2), sinotubular junction (3 x 2), ascending aorta (3) and pulmonary trunk (3). Under stable hemodynamic conditions, geometric changes were time-related to left ventricular pressure (LV) and aortic pressure. RESULTS: The expansion of the aortic root is twice that of the pulmonary root. During the cardiac cycle, the aortic root volume increased by 37.7 +/- 2.7% (mean +/- SEM) versus 20.9 +/- 1.0% for the pulmonary root. Both were cone-shaped at end diastole. Because expansion at commissures was twice that of the base, both roots became more cylindrical during ejection. Although both roots started to expand prior to ejection and reached maximal expansion during the first third of ejection, the commissural and sinotubular junction dynamics were different in each root. While in the aortic root, expansion at commissural and sinotubular junction levels was significantly different (63.7 +/- 3.6% versus 37.0 +/- 2.1%), in the pulmonary root, they were similar (29.0 +/- 1.3% versus 27.7 +/- 1.4%). Expansion of the three sinuses was also different (P<0.001). In the aortic root: the right expanded more than the left and more than the non-coronary sinus. In the pulmonary root: the right sinus expanded more than the anterior more than the left. CONCLUSIONS: Dynamic differences might explain the global pulmonary root dilatation when subjected to systemic pressure, particularly at the level of the sinotubular junction which might result in the autograft failure. Differences in the asymmetrical expansion of the aortic and pulmonary roots should be considered for the implantation of the pulmonary autograft in the most physiological position.