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It was recently shown that the use of Coulomb logarithms appropriate for bremsstrahlung radiation (rather than transport processes) along with corrections for the Langdon effect and ion screening reproduced measurements of collisional absorption in well-characterized underdense plasmas [D. Turnbull et al., Phys. Rev. Lett. 130, 145103 (2023)]. However, it was recognized at the time that the use of the standard absorption-reduction factor from Langdon's seminal paper was inconsistent with the use of Coulomb logarithms that are thermally averaged over a Maxwellian electron-velocity distribution function. A more accurate approach would be to average over the expected super-Gaussian distribution function while accounting for the Gaunt factor's velocity dependence, which somewhat mitigates the Langdon effect; however, at that time, this theory matched the data less well. This conflict is now eliminated with the additional insight that the ionization state of our mid-Z ion species (when present) was lower than had been assumed, as evidenced by the Thomson-scattering data and time-dependent Cretin simulations. We are now able to show that an improved treatment of the Langdon effect provides the best match to data. Otherwise, the prior conclusions remain unchanged. We also show an example of the substantial expected impact to the absorption rate in calculations of indirect-drive hohlraums. [ABSTRACT FROM AUTHOR]

The Dorchap Dyke Swarm hosts the first recorded occurrence of lithium–caesium–tantalum (LCT) pegmatites in Victoria, Australia. Syn-orogenic emplacement of pegmatite dykes occurred along a northwest-trending shear system during the Benambran Orogeny. Pegmatites are derived from fractionated melt associated with the Mount Wills Granite, which is an S-type, peraluminous granite originating from supracrustal melting of Ordovician sedimentary sequences. A distinct, eastward-oriented fractionation trend across the Dorchap Dyke Swarm has highlighted a 20 × 8 km highly fractionated zone in the northeastern Dorchap Range, which includes spodumene- and petalite-bearing pegmatites. A distinct pattern of elemental enrichment (P > Cs > Be > Nb ≥ Ta > Li > Sn) is observed across the strongly fractionated zone of the Dorchap Dyke Swarm. Subsequent metasomatic fluid movements and hydrothermal overprinting have resulted in redistribution of mobile elements in the Dorchap Range, either as hydrothermal alteration species or in some instances as the development of exomorphic halos. Additionally, a regional alteration overprint, likely associated with subsequent metamorphism of pegmatite dykes has resulted in alteration of primary petalite to spodumene plus quartz, and primary spodumene to cookeite. Bulk rock geochemical data from the Dorchap Dyke Swarm suggest a syn-collisional setting for dyke intrusion, consistent with the inferred tectonic setting of the central Lachlan Fold Belt at the time of pegmatite emplacement. Pegmatite dykes locally contain an overprinted structural foliation, which is consistent with the primary structural trend of deformed metasediments and may indicate that dyke emplacement was syngenetic with regional folding and compression of the surrounding Omeo Metamorphic Complex during the Benambran Orogeny. Subsequent hydrothermal alteration of some dykes likely occurred immediately following the Bindian Orogeny. Dorchap Dyke Swarm are the first recorded Li–Cs–Ta pegmatites in Victoria, Australia. Pegmatites were emplaced synchronous with or immediately following the Benambran Orogeny. Dorchap Dyke Swarm pegmatites are geochemically correlated with the Mount Wills Granite. [ABSTRACT FROM AUTHOR]

Measurements of laser absorption in high-temperature, underdense plasmas produced at the Omega Laser Facility are made using two near-field imaging detectors that diagnose the spatial profile and energy of the port P9 beam before and after it transmits through the plasma. The incident beam is sampled using a partial reflection from a full-aperture, (30 cm-diam) uncoated wedge pickoff located before the target chamber vacuum window and final focus lens assembly. A concave mirror reduces the reflected beam size, allowing it to be recorded directly using a charged-coupled device (CCD) camera. The P9 transmitted beam diagnostic (P9TBD) characterizes the transmitted light by terminating the expanded beam on a semi-transparent diffuser and imaging the illuminated surface using a lens and CCD camera. The P9TBD samples a numerical aperture twice as large as the input beam, allowing the energy of transmitted beams with moderate levels of beam spray to be measured accurately. Calibration shots with no plasma provide a path to infer absorption without absolute photometric calibration of either detector. The cross-calibration between the two detectors was measured to remain stable at ±200 ppm, enabling measurements of total beam absorption below 1% with ±0.07% error. [ABSTRACT FROM AUTHOR]

A transmitted-beam diagnostic (P9TBD) was developed as part of a new experimental platform used to study laser–plasma interactions on OMEGA. Located in the opposing port to the wavelength-tunable (350 nm to 353 nm) UV drive beam, the P9TBD characterizes the beam after it propagates through an undersense plasma. The instrument consists of a large-aperture window that allows light to exit the target chamber and project onto a thin sheet of semi-transparent diffuser material. Light transmitted through the diffuser is recorded using a time-integrated camera and a fiber-optically coupled streaked spectrometer, providing measurements of the energy, power, fluence, polarization, and spectrum of the transmitted beam. The diagnostic enables direct observation of a variety of cross-beam energy transfer phenomena, such as wavelength detuning, polarization effects, and gain saturation. [ABSTRACT FROM AUTHOR]

Higher levels of hot electrons from the two-plasmon–decay instability are observed when smoothing by spectral dispersion (SSD) is turned off in directly driven inertial confinement fusion experiments at the Omega Laser Facility. This finding is explained using a hot-spot model based on speckle statistics and simulation results from the laser–plasma simulation environment. The model accurately reproduces the relative increase in hot-electron activity at two different drive intensities although it slightly overestimates the absolute number of hot electrons in all cases. Extrapolating from the current ≈ 360 -GHz system while adhering to the logic of the hot-spot model suggests that a larger SSD bandwidth should significantly mitigate hot-electron generation, and legacy 1-THz OMEGA experiments appear to support this conclusion. These results demonstrate that it is essential to account for laser speckles and spatiotemporal smoothing to obtain quantitative agreement with experiments. A compilation of hot-electron data from the past two decades reveals several other important points: (1) many prior experiments are more easily understood using recent results from multibeam absolute instability theory and (2) experiments with ignition-scale conditions produce less hot electrons compared to OMEGA spherical experiments for a given vacuum overlapped intensity, which is a promising result for validating performance predictions based on hydrodynamic scaling relations. [ABSTRACT FROM AUTHOR]

A fundamental challenge associated with measuring Thomson scattering comes from the small scattering cross section associated with the interaction. To improve photon statistics, a powerful Thomson-scattering probe laser is required. Ponderomotive self-focusing limits the maximum power in the Thomson-scattering probe and was shown to limit the maximum achievable Thomson-scattering signal-to-noise ratio. Operating the laser at powers above the self-focusing critical power was shown to cause beam degradation, which reduced the amount of collected Thomson-scattered light. Using a phase plate was shown to improve laser beam propagation and consequently improve the signal-to-noise ratio in the measured spectrum. [ABSTRACT FROM AUTHOR]

A fast, accurate and stable optimization algorithm is very important for inverse planning of intensity-modulated radiation therapy (IMRT), and for implementing dose-adaptive radiotherapy in the future. Conventional numerical search algorithms with positive beam weight constraints generally require numerous iterations and may produce suboptimal dose results due to trapping in local minima regions of the objective function landscape. A direct solution of the inverse problem using conventional quadratic objective functions without positive beam constraints is more efficient but it will result in unrealistic negative beam weights. We review here a direct solution of the inverse problem that is efficient and does not yield unphysical negative beam weights. In fast inverse dose optimization (FIDO) method the objective function for the optimization of a large number of beamlets is reformulated such that the optimization problem is reducible to a linear set of equations. The optimal set of intensities is then found through a matrix inversion, and negative beamlet intensities are avoided without the need for externally imposed ad hoc conditions. In its original version [S. P. Goldman, J. Z. Chen, and J. J. Battista, in Proceedings of the XIVth International Conference on the Use of Computers in Radiation Therapy, 2004, pp. 112–115; S. P. Goldman, J. Z. Chen, and J. J. Battista, Med. Phys. 32, 3007 (2005)], FIDO was tested on single two-dimensional computed tomography (CT) slices with sharp KERMA beams without scatter, in order to establish a proof of concept which demonstrated that FIDO could be a viable method for the optimization of cancer treatment plans. In this paper we introduce the latest advancements in FIDO that now include not only its application to three-dimensional volumes irradiated by beams with full scatter but include as well a complete implementation of clinical dose-volume constraints including maximum and minimum dose as well as equivalent uniform dose constraints. The method has been integrated into a commercial treatment planning system (Pinnacle, Philips Medical Systems) for beta testing using clinical radiotherapy cases and standard dose constraints set by radiation oncologists. Our FIDO method consistently delivered excellent treatment plans comparable and often better than those obtained using standard optimization techniques that are considerably slower. By design, FIDO is guaranteed to find a global minimum and will achieve highly conformal and homogeneous dose distributions without the need for artificial internal contours that must be created in conventional IMRT optimization systems to help the search engines better control some beam entry directions and in this way avoid the creation of hot and cold spots. This method provides a fast, intuitive and robust technique that yields excellent results for the inverse planning of IMRT. FIDO’s ability to efficiently optimize very large numbers of beamlet weights also makes it an ideal tool for the optimization of helical tomotherapy. Future gains in speed will make it possible to use FIDO for instant treatment plan reoptimization using CT images produced at the radiotherapy machine, just prior to daily treatments of the patient. [ABSTRACT FROM AUTHOR]

Recent experimental and theoretical results have shown that crossing a probe laser in a plasma with a secondary pump can modify the amplitude, phase, and polarization of the probe in a controlled manner. Beyond fundamental physics, these results suggest that a pump-plasma based optical system could be used to amplify and control a laser pulse at high power, where the high fluence precludes using an optical system. This paper attempts to clarify the transient regime of such a pump-probe-plasma system. An analytical solution is derived to the coupled equations in the relevant regime, valid for any frequency detuning, coupling strength, and damping. Asymptotic expressions in the scantly studied off-resonance regime are derived. The time to reach the steady state is found to be roughly independent of the detuning. This time-to-steady-state defines the response time of such a plasma photonics system and can be made potentially much faster than traditional optics by controlling the damping of plasma acoustic waves. We comment on the steady-state assumption typically used to interpret current experiments and design future ones. [ABSTRACT FROM AUTHOR]

Provides information on a study that examined luminescence properties of GaN layers grown by metalorganic chemical vapor deposition on sapphire substrates with GaN/AIN double buffer layers or GaN single buffer layers. Methodology of the study; Results and discussion on the study.

Focuses on a study which explored photoluminescence and photoluminescence excitation spectroscopic analysis of Dy[sub2]S[sub3]-doped As[sub12]Ge[sub33]Se[sub55] glasses. Background on rare earth-doped oxide glasses; Description of the experimental setup; Results and discussion.

An electric dipole moment function (EDMF) for OH has been derived by combining airglow and laboratory intensity measurements with recent high precision measurements of the dipole moments for v=0,1, and 2. This empirical EDMF shows remarkable agreement with the a priori MCSCF(7)-SCEP EDMF. However, it differs sufficiently to produce transition probabilities which are in much better agreement with observations than previously available sets. [ABSTRACT FROM AUTHOR]

Combining laser beams in a plasma is enabled by seeded stimulated Brillouin scattering which allows cross-beam energy transfer (CBET) to occur and re-distributes the energy between beams that cross with different incident angles and small differences in wavelength [Kirkwood et al. Phys. Plasmas 4, 1800 (1997)]. Indirect-drive implosions at the National Ignition Facility (NIF) [Haynam et al. Appl. Opt. 46, 3276–3303 (2007)] have controlled drive symmetry by using plasma amplifiers to transfer energy between beams [Kirkwood et al., Plasma Phys. Controlled Fusion 55, 103001 (2013); Lindl et al., Phys. Plasmas 21, 020501 (2014); and Hurricane et al. Nature 506, 343–348 (2014)]. In this work, we show that the existing models are well enough validated by experiments to allow a design of a plasma beam combiner that, once optimized, is expected to produce a pulse of light in a single beam with the energy greatly enhanced over existing sources. The scheme combines up to 61 NIF beams with 120 kJ of available energy into a single f/20 beam with a 1 ns pulse duration and a 351 nm wavelength by both resonant and off-resonance CBET. Initial experiments are also described that have already succeeded in producing a 4 kJ, 1 ns pulse in a single beam by combination of up to eight incident pump beams containing <1.1 kJ/beam, which are maintained near resonance for CBET in a plasma that is formed by 60 pre-heating beams [Kirkwood et al., Nat. Phys. 14, 80 (2018)]. [ABSTRACT FROM AUTHOR]

Erratum: "Mitigation of self-focusing in Thomson scattering experiments" [Phys. The signal-to-noise ratio for a Thomson-scattering probe beam with a phase plate was calculated at the peaks of the collective ion-acoustic wave (blue dots) and electron-plasma wave (red dash) features for ne = 8.5 × 1019 cm-3, Te/Ti = 4, and Z = 1 and Z = 7 in a 55% hydrogen and 45% nitrogen mix. A Thomson-scattered spectrum wavelength resolved into bins sufficient to resolve the peak locations of both the electron plasma (outer two) and ion acoustic (inner two) wave features. [Extracted from the article]

Controlling the symmetry of indirect-drive inertial confinement fusion implosions remains a key challenge. Increasing the ratio of the hohlraum diameter to the capsule diameter (case-to-capsule ratio, or CCR) facilitates symmetry tuning. By varying the balance of energy between the inner and outer cones as well as the incident laser pulse length, we demonstrate the ability to tune from oblate, through round, to prolate at a CCR of 3.2 in near-vacuum hohlraums at the National Ignition Facility, developing empirical playbooks along the way for cone fraction sensitivity of various laser pulse epochs. Radiation-hydrodynamic simulations with enhanced inner beam propagation reproduce most experimental observables, including hot spot shape, for a majority of implosions. Specular reflections are used to diagnose the limits of inner beam propagation as a function of pulse length. [ABSTRACT FROM AUTHOR]

Background. Substantial healthcare resources are devoted to panic disorder (PD) and coronary heart disease (CHD); however, the association between these conditions remains controversial. Our objective was to conduct a systematic review of studies assessing the association between PD, related syndromes, and incident CHD. Method. Relevant studies were retrieved from Medline, EMBASE, SCOPUS and PsycINFO without restrictions from inception to January 2015 supplemented with hand-searching. We included studies that reported hazard ratios (HR) or sufficient data to calculate the risk ratio and 95% confidence interval (CI) which were pooled using a random-effects model. Studies utilizing self-reported CHD were ineligible. Twelve studies were included comprising 1 131 612 persons and 58 111 incident CHD cases. Results. PD was associated with the primary incident CHD endpoint [adjusted HR (aHR) 1.47, 95% CI 1.24-1.74, p < 0.00001] even after excluding angina (aHR 1.49, 95% CI 1.22-1.81, p < 0.00001). High to moderate quality evidence suggested an association with incident major adverse cardiac events (MACE; aHR 1.40, 95% CI 1.16-1.69, p = 0.0004) and myocardial infarction (aHR 1.36, 95% CI 1.12-1.66, p = 0.002). The risk for CHD was significant after excluding depression (aHR 1.64, 95% CI 1.45-1.85) and after depression adjustment (aHR 1.38, 95% CI 1.03-1.87). Age, sex, length of follow-up, socioeconomic status and diabetes were sources of heterogeneity in the primary endpoint. Conclusions. Meta-analysis showed that PD was independently associated with incident CHD, myocardial infarction and MACE; however, reverse causality cannot be ruled out and there was evidence of heterogeneity. [ABSTRACT FROM AUTHOR]

We present the first observations of multibeam weakly seeded Brillouin sidescatter in indirect-drive inertial confinement fusion (ICF) experiments. Two seeding mechanisms have been identified and quantified: specular reflections ("glint") from opposite hemisphere beams, and Brillouin backscatter from neighboring beams with a different angle of incidence. Seeded sidescatter can dominate the overall coupling losses, so understanding this process is crucial for proper accounting of energy deposition and drive symmetry. Glint-seeded scattered light could also be used to probe hydrodynamic conditions inside ICF targets. [ABSTRACT FROM AUTHOR]

Background: Midwife-managed programmes of care are being widely implemented although there has been little investigation of their efficacy. We have compared midwife-managed care with shared care (ie, care divided among midwives, hospital doctors, and general practitioners) in terms of clinical efficacy and women's satisfaction.Methods: We carried out a randomised controlled trial of 1299 pregnant women who had no adverse characteristics at booking (consent rate 81.9%). 648 women were assigned midwife-managed care and 651 shared care. The research hypothesis was that compared with shared care, midwife-managed care would produce fewer interventions, similar (or more favourable) outcomes, similar complications, and greater satisfaction with care. Data were collected by retrospective review of case records and self-report questionnaires. Analysis was by intention to treat.Findings: Interventions were similar in the two groups or lower with midwife-managed care. For example, women in the midwife-managed group were less likely than women in shared care to have induction of labour (146 [23.9%] vs 199 [33.3%]; 95% CI for difference 4.4-14.5). Women in the midwife-managed group were more likely to have an intact perineum and less likely to have had an episiotomy (p = 0.02), with no significant difference in perineal tears. Complication rates were similar. Overall, 32.8% of women were permanently transferred from midwife-managed care (28.7% for clinical reasons, 3.7% for non-clinical reasons). Women in both groups reported satisfaction with their care but the midwife-managed group were significantly more satisfied with their antenatal (difference in mean scores 0.48 [95% CI 0.41-0.55]), intrapartum (0.28 [0.18-0.37]), hospital-based postnatal care (0.57 [0.45-0.70]), and home-based postnatal care (0.33 [0.25-0.42]).Interpretation: We conclude that midwife-managed care for healthy women, integrated within existing services, is clinically effective and enhances women's satisfaction with maternity care. [ABSTRACT FROM AUTHOR]

Overweight and obesity during pregnancy is associated with risk of a range of adverse health outcomes. While intervention studies aim to promote behavioral change, little is known about the underlying psychological mechanisms facilitating and hindering change. The aim of this study was to evaluate overweight and obese women’s perceptions of making behavior change during pregnancy. We explored beliefs through self-administrated questionnaires (n = 464) and semi-structured face-to-face interviews (n = 26). Questions were designed according to the Health Belief Model. A triangulation protocol was followed to combine quantitative and qualitative data. A total of 269 women (58 %) indicated that high gestational weight gain is a concern, with 348 (75 %) indicating excessive weight gain is associated with complications during pregnancy or child birth. Women were aware of maternal complications associated with high gestational weight gain, but had more limited awareness of neonatal complications. While most women indicated in questionnaires that healthy eating and physical activity were associated with improved health during pregnancy, they were unable to identify specific benefits at interview. Barriers to making healthy behavior changes were highly individualized, the main barrier being lack of time. While the majority (91 %) of women indicated that they would make behavior changes if the change made them feel better, only half felt confident in their ability to do so. Interventions for overweight and obese pregnant women should incorporate education about neonatal health consequences and benefits of healthy behavior change in addition to incorporating strategies to enhance self-efficacy. [ABSTRACT FROM AUTHOR]

Issue Addressed: This study used the Transtheoretical Model of Behaviour Change (TTM) to describe reparticipation in colorectal cancer (CRC) screening according to social cognitive and background variables.Methods: A random sample of men and women aged 50-74 years living in South Australia completed a questionnaire measuring TTM stage and attitudes toward screening using a faecal occult blood test (FOBT). Participants were categorised according to four stages of readiness to rescreen: action, maintenance, relapse and inconsistent. Multivariate techniques were used to determine predictors of lower readiness stages compared with maintenance.Results: Of the 849 study participants, 29.9% were either non-adherent or had no intentions to maintain adherence (inconsistent and relapse). Compared with maintenance rescreeners, relapse participants reported less: social influences to screen (RR=0.86, p<0.001); satisfaction with prior screening (RR=0.87, p=0.03), self-efficacy (RR=0.96, p=0.01); and screening benefits (RR=0.84, p<0.001). Relapse participants were also more likely to not have private health insurance (RR=1.33, p=0.04) and be unaware of the need to repeat screening (RR=1.41, p=0.02). Inconsistent screeners were less likely to have planned when they will next rescreen (RR= 0.84, p=0.04) and reported greater barriers to rescreening (RR=1.05, p=0.05). Action participants were younger (RR= 0.98, p=<0.001), reported less social influences to screen (RR=0.94, p<0.001) and were less likely to have known someone who has had CRC (RR=0.82, p=0.01).Conclusions: Social cognitive, demographic and background variables significantly differentiated screening maintenance from lower readiness stages. [ABSTRACT FROM AUTHOR]

In a Raman plasma amplifier, the aim is to create plasma conditions in which Raman backscattering is the fastest growing instability, outrunning all competing effects so that it is possible to amplify and compress a laser beam to unprecedented unfocused intensities by utilizing that instability. However, achieving high efficiencies via this scheme has proven very difficult experimentally. Recent data show the simultaneous occurrence of stimulated Raman scattering (SRS), stimulated Brillouin scattering (SBS), and stimulated electron-acoustic scattering (SEAS). The appearance of SEAS is indicative of strong particle trapping, the existence of which is hard to justify without highlighting the interplay between SRS and SBS. [ABSTRACT FROM AUTHOR]

Ray-based cross-beam energy transfer (CBET) models have become a common feature of the radiation-hydrodynamic codes used to simulate inertial confinement fusion experiments. These models are necessary for achieving better agreement with experimental measurements, but their detailed implementation can vary widely between the codes and often rely on artificial multipliers. To address this, a series of 2D and 3D test cases has been developed with validated solutions from wave-based calculations. Comparisons of various ray-based CBET models to the wave-based calculations highlight the essential physics that is required for accurate ray-based CBET modeling. Quantitative comparison metrics and/or field data from the wave-based calculations have been made available for use in the validation of other ray-based CBET codes. [ABSTRACT FROM AUTHOR]

We compared the effect of delivering fluid warmed using two methods in 76 adult patients having short duration surgery. All patients received a litre of crystalloid delivered either at room temperature, warmed using an in-line warming device or pre-warmed in a warming cabinet for at least 8 h. The tympanic temperature of those receiving fluid at room temperature was 0.4 °C lower on arrival in recovery when compared with those receiving fluid from a warming cabinet (p = 0.008). Core temperature was below the hypothermic threshold of 36.0 °C in seven (14%) patients receiving either type of warm fluid, compared to eight (32%) patients receiving fluid at room temperature (p = 0.03). The administration of 1 l warmed fluid to patients having short duration general anaesthesia results in higher postoperative temperatures. Pre-warmed fluid, administered within 30 min of its removal from a warming cabinet, is as efficient at preventing peri-operative hypothermia as that delivered through an in-line warming system. [ABSTRACT FROM AUTHOR]

Gastroenterologists should be able to refer patients directly to psychologists with full Medicare reimbursement. Psychological comorbidities are frequently seen in patients with gastrointestinal conditions. However, time pressure and lack of expertise in non-medical therapies of psychological problems prevent gastroenterologists from initiating psychological treatment although such treatment may improve patients’ outcomes and reduce health-care utilization. Psychologists are needed as part of the multidisciplinary team in gastroenterology clinics in Australia to take the leading role in the psychological management of those patients by contributing to screening, faster diagnosis and treatment of depression and anxiety disorders in particular. [ABSTRACT FROM AUTHOR]

In 1998, Wallace et al. ( Science 1988; 242: 1427–30) published evidence that the mutation m.11778G>A was responsible for causing Leber’s hereditary optic neuropathy. This was the first account of a mitochondrial DNA mutation being irrefutably linked with a human disease and was swiftly followed by a report from Holt et al. ( Nature 1988; 331: 717–9) identifying deletions in mitochondrial DNA as a cause for myopathy. During the subsequent 20 years there has been an exponential growth in ‘mitochondrial medicine’, with clinical, biochemical and genetic characterizations of a wide range of mitochondrial diseases and evidence implicating mitochondria in a host of many other clinical conditions including ageing, neurodegenerative illness and cancer. In this review we shall focus on the diagnosis and management of mitochondrial diseases that lead directly or indirectly to disruption of the process of oxidative phosphorylation. [ABSTRACT FROM AUTHOR]

Background Symptoms of functional gastrointestinal disorders (FGIDs) are common in patients with inflammatory bowel disease (IBD). Psychological comorbidities of anxiety and depression are also highly prevalent in IBD. Aim To quantify the burden of FGIDs in a hospital-based cohort of patients with IBD and to determine whether there is any inter-relationship between the presence and number of FGIDs and patients’ quality of life or psychological status. Methods A cross-sectional survey of 61 out-patients was performed. Data on psychological status, quality of life, disease activity and functional symptoms according to Rome III criteria were collected. Results Overall, 49 (80%) participants met Rome III criteria for a functional bowel disorder and 52% of participants met criteria for more than one FGID. Participants with no FGID had significantly better physical quality of life than those with more than two FGIDs ( P = 0.025). However, there was no relationship among the number of FGIDs, mental quality of life, anxiety or depression. Conclusions Functional gastrointestinal disorders are highly prevalent in out-patients with IBD. Somewhat unexpectedly, the presence of anxiety and/or depression did not appear to correlate with either the presence or the number of FGIDs. [ABSTRACT FROM AUTHOR]

Carbon dioxide is known to affect consciousness in animals and humans. We surmised that changes in end-tidal carbon dioxide during anaesthesia might affect the Bispectral Index. Twenty-four patients due to undergo surgery were anaesthetised with fentanyl and a propofol infusion. The Bispectral Index, pulse rate and blood pressure were recorded while end-tidal carbon dioxide levels were changed. The patients acted as their own controls as they were subjected to high, normal and low levels of end-tidal carbon dioxide (3–12 kPa) according to a randomised sequence. There were no changes in the Bispectral Index or haemodynamic variables resulting from manipulation of the end-tidal carbon dioxide. At the level of hypnosis involved in this study, changes in end-tidal carbon dioxide, within the range tested, do not result in changes in the Bispectral Index. [ABSTRACT FROM AUTHOR]

Maternally inherited diabetes and deafness (MIDD) affects up to 1% of patients with diabetes but is often unrecognized by physicians. It is important to make an accurate genetic diagnosis, as there are implications for clinical investigation, diagnosis, management and genetic counselling. This review summarizes the range of clinical phenotypes associated with MIDD; outlines the advances in genetic diagnosis and pathogenesis of MIDD; summarizes the published prevalence data and provides guidance on the clinical management of these patients and their families. [ABSTRACT FROM AUTHOR]

Background: The diagnosis of abdominal compartment syndrome depends upon the demonstration of an elevated intra-abdominal pressure (IAP). Direct measures of IAP are impractical in the critical care unit; intravesical pressure (IVP) and intragastric pressure (IGP) should represent acceptable surrogate measures. IVP is the preferred measure of IAP in critical care. We considered that IGP represents a practical alternative. The objective of this preliminary study was to observe the relationship between IGP and IAP.Methods: After Institutional Ethics Board approval, 29 patients having elective laparoscopic surgery were recruited. IAP was measured directly via the abdominal trochar. This was compared with IGP measured via a commercial balloon catheter placed into the stomach.Results: Measured IGP was always more positive than IAP; both showed linear correlation (r2>0.9). When IGP was calibrated against IAP, an estimated difference between the IGP and IAP of+/-2.5 mm Hg for 95% of the measurements was seen.Conclusions: The study demonstrates the strength of the relationship between IGP and IAP in normal individuals. Application of IGP measurement in the critical care patient is necessary to demonstrate its suitability for continuous IAP assessment. [ABSTRACT FROM AUTHOR]

Summary Lower limb compartment syndrome is a rare consequence of surgery where the lithotomy position is maintained for several hours. The aim of this study was to observe the effect of the lithotomy position on lower limb compartment pressure and blood flow to the lower limb in surgical patients having colorectal procedures. We prospectively studied 23 patients undergoing colorectal surgery requiring the lithotomy position and recorded lower limb compartment pressure, and the blood pressure in the upper and lower limbs. The lithotomy position led to a significant (p < 0.001) fall in blood pressure to the lower limb from 87 (SD 16) mmHg to 67.9 (SD 12) mmHg and a significant (p < 0.001) rise in lower limb compartment pressure from 13 (SD 7) mmHg to 31 (SD 12) mmHg. These two effects compromise blood flow to the lower limb in long surgical procedures where the lithotomy position is required. Intermittently lowering the legs and restoring blood flow may prevent compartment syndrome developing. [ABSTRACT FROM AUTHOR]

BACKGROUND: The steadily increasing global rates of cesarean section has become one of the most debated topics in maternity care. This paper reviews and reports on the success of strategies that have been developed in response to this continuing challenge. METHODS: A literature search identified studies conducted between 1985 and 2001 from the Cochrane Database of Systematic Reviews, Medline, Sociofile, Current Contents, Psyclit, Cinahl, and EconLit databases. An additional search of electronic databases for Level 1 evidence (systematic reviews), Level 2 (randomized controlled trials), Level 3 (quasi-experimental studies), or Level 4 (observational studies) was performed. Selection criteria used to identify studies for review included types of study participant, intervention, outcome measure, and study. RESULTS: Interventions that have been used in an attempt to reduce cesarean section rates were identified; they are categorized as psychosocial, clinical, and structural strategies. Two clinical interventions, (external cephalic version, vaginal birth after a previous cesarean) and one psychosocial intervention (one-to-one trained support during labor) demonstrated Level 1 evidence for reducing cesarean section rates. CONCLUSIONS: Although the evidence for one-to-one care and external cephalic version came from both developed and developing settings, the systematic review for vaginal birth after a cesarean was restricted to studies conducted in the United States. The effective implementation of the preceding strategies to reduce cesarean rates may depend on the social and cultural milieu and on associated beliefs and practices. [ABSTRACT FROM AUTHOR]

Stellate ganglion block is a procedure frequently used for the management of patients with chronic sympathetically mediated pain affecting the arm, neck or head. We studied the effect of stellate ganglion block on ipsilateral phrenic nerve function, and hence diaphragmatic strength, in 11 adult patients with chronic sympathetically mediated pain. Pre- and post-block forced vital capacity (FVC) measurements were recorded using a pneumotachograph and a Magstim nerve stimulator was used to generate pre- and post-block twitch mouth pressures (PTWM). This device can be used to stimulate the phrenic nerves and hence the diaphragm. The resulting change in airway pressure was measured at the mouth and has previously been shown to reflect diaphragm strength. There was no statistically significant difference in FVC or PTWM pre- or post stellate ganglion block. In conclusion, a stellate ganglion block has no adverse effect on ipsilateral phrenic nerve function or diaphragm strength in healthy adult patients. [ABSTRACT FROM AUTHOR]

The Lloyd Davies position was developed to facilitate access to the pelvis for gynaecological, urological and colorectal procedures. Previous case reports have demonstrated that prolonged adoption (> 4 h) of this position has been associated with the development of bilateral compartment syndrome of the calves. All three patients reported here suffered severe bilateral calf pain despite the use of thoracic epidurals. All three cases required three-compartment fasciotomies and, 6 months after surgery, were all still severely disabled as a consequence of the compartment syndrome. These case reports stress the dangers of use of the Lloyd Davies position for prolonged procedures and demonstrate that some patients are at risk after relatively short periods (< 3 h). Previous case reports and clinical studies have focused on the effect of limb elevation in stirrups on the arterial pressure in the lower limb. We review the pathophysiology of compartment syndrome and consider factors other than a decrease in arterial pressure that may predispose to compartment syndrome during adoption of the Lloyd Davies position. [ABSTRACT FROM AUTHOR]

BACKGROUND: Current forms of analgesia often have significant side effects for women in labor. Bathing in warm water during labor has been reported to increase a woman's comfort level and cause a reduction in painful contractions. The objective of this trial was to compare immersion in warm water during labor with traditional pain management for a range of clinical and psychological outcomes. METHODS: A prospective randomized controlled trial of 274 pregnant women, who were free from medical and obstetric complications and expecting a singleton pregnancy at term, was conducted at the Women's and Children's Hospital, a maternity tertiary referral center in Adelaide, South Australia. Women in labor were randomized to an experimental group who received immersion in a bath or to a nonbath group who received routine care. Pharmacological pain relief was the primary outcome that was measured, and secondary outcomes included maternal and neonatal clinical outcomes, factors relating to maternal and neonatal infectious morbidity, psychological outcomes, and satisfaction with care. RESULTS: The use of pharmacological analgesia was similar for both the experimental and control groups; 85 and 77 percent, respectively, used major analgesia. No statistical differences were observed in the proportion of women requiring induction and augmentation of labor or in rates of perineal trauma, length of labor, mode of delivery, or frequency of cardiotocographic trace abnormalities. Neonatal outcomes (birthweight, Apgar score, nursery care, meconium-stained liquor, cord pH estimations) revealed no statistically significant differences. Infants of bath group women required significantly more resuscitation than routine group women. Routine group women rated their overall experience of childbirth more positively than bath group women. Psychological outcomes, such as satisfaction with care or postnatal distress, were the same for both groups. CONCLUSION: Bathing in labor confers no clear benefits for the laboring woman but may contribute to adverse effects in the neonate. [ABSTRACT FROM AUTHOR]

Discusses a study which measured the proportion of mutant mitochondrial DNA (mtDNA) in primary oocytes from the ovary of a woman who harbored the A3243G mtDNA mutation. Frequency distribution for the oocyte mutation load; Difference between the rates of segregation of the mutations; Method to estimate the size of the mitochondrial genetic bottleneck.

Focuses on a study which determined whether recombination has contributed to the distribution of human mitochondrial genome (mtDNA) polymorphisms in humans. Nucleotide sequences of mtDNA in the European population; Analysis of mtDNA linkage disequilibrium as a function of distance; Excess homoplasy test for recombination.

Polarimetry has been added to the full aperture backscatter diagnostic on the NIF. Wollaston prisms are used to sample a small region of a beam's backscatter, effectively separating it into two linear polarizations, one of which is parallel to the incident beam. A time-averaged measurement of each polarization is obtained by imaging the separated spots off of a scatter plate. Results have improved understanding of crossed beam energy transfer, glint, and sidescatter, and motivated plans to upgrade to a time-resolved polarimeter measuring the full Stokes vector. [ABSTRACT FROM AUTHOR]

Radiation-hydrodynamic simulations of directly driven fusion experiments at the Omega Laser Facility predict absorption accurately when targets are driven at low overlapped laser intensity. Discrepancies appear at increased intensity, however, with higher-than-expected laser absorption on target. Strong correlations with signatures of the two-plasmon decay (TPD) instability--including half-harmonic and hard-x-ray emission--indicate that TPD is responsible for this anomalous absorption. Scattered light data suggest that up to ≈30% of the laser power reaching quarter-critical density can be absorbed locally when the TPD threshold is exceeded. A scaling of absorption versus TPD threshold parameter was empirically determined and validated using the laser-plasma simulation environment code. [ABSTRACT FROM AUTHOR]

A high-intensity laser pulse propagating through a medium triggers an ionization front that can accelerate and frequency upshift the photons of a second pulse. The maximum upshift is ultimately limited by the accelerated photons outpacing the ionization front or the ionizing pulse refracting from the plasma. Here, we apply the flying focus--a moving focal point resulting from a chirped laser pulse focused by a chromatic lens--to overcome these limitations. Theory and simulations demonstrate that the ionization front produced by a flying focus can frequency upshift an ultrashort optical pulse to the extreme ultraviolet over a centimeter of propagation. An analytic model of the upshift predicts that this scheme could be scaled to a novel tabletop source of spatially coherent x rays. [ABSTRACT FROM AUTHOR]

Background: Cardiotocography is almost ubiquitous in its use in intrapartum care. Although it has been demonstrated that there is some benefit from continuous intrapartum fetal monitoring using cardiotocography, there is also an increased risk of caesarean section which is accompanied by short-term and long-term risks to the mother and child. There is considerable potential to reduce unnecessary operative delivery with up to a 60% false positive diagnosis of fetal distress using cardiotocography alone. ST analysis of the fetal electrocardiogram is a promising adjunct to cardiotocography alone, and permits detection of metabolic acidosis of the fetus, potentially reducing false positive diagnosis of fetal distress.Methods: This study will be a single-centre, parallel-group, randomised controlled trial, conducted over 3 years. The primary hypothesis will be that the proportion of women with an emergency caesarean section on ST analysis will not equal that for women on cardiotocography monitoring alone. Participants will be recruited at the Women's and Children's Hospital, a high-risk specialty facility with approximately 5000 deliveries per annum. A total of 1818 women will be randomised to the treatment or conventional arm with an allocation ratio of 1:1, stratified by parity. The primary outcome is emergency caesarean section (yes/no). Statistical analysis will follow standard methods for randomised trials and will be performed on an intention-to-treat basis. Secondary maternal and neonatal outcomes will also be analysed. Additional study outcomes include psychosocial outcomes, patient preferences and cost-effectiveness.Discussion: Approximately 20% of Australian babies are delivered by emergency caesarean section. This will be the first Australian trial to examine ST analysis of the fetal electrocardiogram as an adjunct to cardiotocography as a potential method for reducing this proportion. The trial will be among the first to comprehensively examine ST analysis, taking into account the impact on psychosocial well-being as well as cost-effectiveness. This research will provide Australian evidence for clinical practice and guideline development as well as for policy-makers and consumers to make informed, evidence-based choices about care in labour.Trial Registration: ANZCTR, ACTRN1261800006268 . Registered on 19 January 2018. [ABSTRACT FROM AUTHOR]

This article presents an investigation to provide students with the opportunity to study the physics of electromagnetic radiation, particularly UV radiation, and the way it interacts with different environments. The protective ability of shade structures is generally misunderstood, and this investigation will give students the basic knowledge that, even though shade structures protect the human body from direct UV radiation, it is now the diffuse UV radiation that is significant in the shade. [ABSTRACT FROM AUTHOR]

Flying focus is a technique that uses a chirped laser beam focused by a highly chromatic lens to produce an extended focal region within which the peak laser intensity can propagate at any velocity. When that intensity is high enough to ionize a background gas, an ionization wave will track the intensity isosurface corresponding to the ionization threshold. We report on the demonstration of such ionization waves of arbitrary velocity. Subluminal and superluminal ionization fronts were produced that propagated both forward and backward relative to the ionizing laser. All backward and all superluminal cases mitigated the issue of ionization-induced refraction that typically inhibits the formation of long, contiguous plasma channels. [ABSTRACT FROM AUTHOR]

We propose a new laser amplifier scheme utilizing stimulated Raman scattering in plasma in conjunction with a "flying focus"--a chromatic focusing system combined with a chirped pump beam that provides spatiotemporal control over the pump's focal spot. Pump intensity isosurfaces are made to propagate at v=-c so as to be in sync with the injected counterpropagating seed pulse. By setting the pump intensity in the interaction region to be just above the ionization threshold of the background gas, an ionization wave is produced that travels at a fixed distance ahead of the seed. Simulations show that this will make it possible to optimize the plasma temperature and mitigate many of the issues that are known to have impacted previous Raman amplification experiments, in particular, the growth of precursors. [ABSTRACT FROM AUTHOR]

The profile and trajectory of cognitive impairment in mitochondrial disease are poorly defined. This systematic review sought to evaluate the current literature on cognition in mitochondrial disease, and to determine future research directions. A systematic review was conducted, employing PubMed, Medline, Psycinfo, Embase and Web of Science, and 360‐degree citation methods. English language papers on adult patients were included. The literature search yielded 2421 articles, of which 167 met inclusion criteria. Case reports and reviews of medical reports of patients yielded broad diagnoses of dementia, cognitive impairment and cognitive decline. In contrast, systematic investigations of cognitive functioning using detailed cognitive batteries identified focal cognitive rather than global deficits. Results were variable, but included visuospatial functioning, memory, attention, processing speed and executive functions. Conclusions from studies have been hampered by small sample sizes, variation in genotype and the breadth and depth of assessments undertaken. Comprehensive cognitive research with concurrent functional neuroimaging and physical correlates of mitochondrial disease in larger samples of well‐characterized patients may discern the aetiology and progression of cognitive deficits. These data provide insights into the pattern and trajectory of cognitive impairments, which are invaluable for clinical monitoring, health planning and clinical trial readiness. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether use of ST analysis of the fetal electrocardiogram (STan) as an adjunct to continuous cardiotocography (CTG) reduces the rate of emergency Cesarean section (EmCS) compared with CTG alone. Methods: This was a randomized controlled trial of patients with a singleton fetus in cephalic presentation at ≥ 36 weeks' gestation, requiring continuous electronic fetal monitoring during labor at a tertiary maternity hospital in Adelaide, Australia, between January 2018 and July 2021. Participants were randomized to undergo CTG + STan or CTG alone. The calculated sample size was 1818 participants. The primary outcome was EmCS. Secondary outcomes included metabolic acidosis, a composite adverse perinatal outcome, and other maternal and neonatal morbidity and safety outcomes. Results: The present study enrolled 970 women, of whom 967 were included in the primary analysis. EmCS occurred in 107/482 (22.2%) deliveries in the CTG + STan arm and in 107/485 (22.1%) in the CTG arm (adjusted relative risk, 1.02 (95% CI, 0.81–1.27); P = 0.89). There was no difference in the rate of adverse maternal or neonatal outcomes between arms. Conclusions: The addition of STan as an adjunct to continuous CTG did not reduce the EmCS rate. The smaller‐than‐anticipated sample size meant that this study was underpowered to detect absolute differences of ≤ 5% and, therefore, this negative finding could be due to a Type‐2 error. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

The influences of ion trapping and fluctuations of electron temperature and plasma flow on cross-beam energy transfer (CBET) are examined using two- and three-dimensional particle-in-cell simulations in parameter regimes relevant to recent CBET experiments at the OMEGA laser facility. In mid-Z plasma irradiated by an intense pump beam and weaker probe beam, ion trapping, collisional de-trapping, and plasma flow induced by thermal effects are shown to affect the CBET gain. Ion trapping can enhance or detune the CBET resonance [Nguyen et al., Phys. Plasmas 28, 082705 (2021)]. Collisional de-trapping can affect the CBET gain at low seed beam intensity near the onset threshold for ion trapping. Thermal-effects-induced flow can also detune the CBET resonance at a level comparable to that from trapping at low seed beam intensity. As a consequence, the CBET gain is sensitive to collisions and dimensionality at low seed beam intensity where ion trapping is weak but is insensitive to collisions and dimensionality at high seed beam intensity where ion trapping is strong. [ABSTRACT FROM AUTHOR]

The compression of direct-drive inertial confinement fusion (ICF) targets is strongly impacted by cross-beam energy transfer (CBET), a laser-plasma instability that limits ablation pressure by redirecting laser energy outward and that is projected to be mitigated by laser bandwidth. Here, we explore various CBET mitigation constraints to guide the design of future ICF facilities. First, we find that the flat, Gaussian, and Lorentzian spectral shapes have similar CBET mitigation properties, and a flat shape with nine spectral lines is a good surrogate for what can be obtained with other spectral shapes. Then, we conduct a comprehensive study across energy scales and ignition designs. 3D hydrodynamic simulations are used to derive an analytical model for the expected CBET mitigation as a function of laser and plasma parameters. From this model, we study the bandwidth requirements of conventional and shock ignition designs across four different energy scales and find that they require between 0.5 and 3 ± 0.2 % relative bandwidth. Best mitigation is achieved when the beam radius over critical radius R b / R c is kept low during the drive while the plasma temperature is kept high. In a steady state, we find that the bandwidth required to mitigate 85% of CBET scales as (R b / R c) 2.15 L n − 0.58 I 0.7 , where Ln is the density scale length, and I the laser intensity. Finally, we find that the chamber beam port layout does not influence CBET mitigation. In the case of a driver using many monochromatic beamlets, we find that ∼10 beamlets per port is required, with diminishing returns above ∼20. [ABSTRACT FROM AUTHOR]

We report the first complete set of measurements of a laser-plasma optical system's refractive index, as seen by a second probe laser beam, as a function of the relative wavelength shift between the two laser beams. Both the imaginary and real refractive index components are found to be in good agreement with linear theory using plasma parameters measured by optical Thomson scattering and interferometry; the former is in contrast to previous work and has implications for crossed-beam energy transfer in indirect-drive inertial confinement fusion, and the latter is measured for the first time. The data include the first demonstration of a laser-plasma polarizer with 85 % - 87 % extinction for the particular laser and plasma parameters used in this experiment, complementing the existing suite of high-power, tunable, and ultrafast plasma-based photonic devices. [ABSTRACT FROM AUTHOR]

An advanced focusing scheme, called a "flying focus," uses a chromatic focusing system combined with a broadband laser pulse with its colors arranged in time to propagate a high intensity focus over a distance that can be much greater than its Rayleigh length while decoupling the speed at which the peak intensity propagates from its group velocity. The flying focus generates a short effective pulse duration with a small diameter focal spot that co- or counter-propagates along the optical axis at any velocity. Experiments validating the concept measured subluminal (−0.09c) to superluminal (39c) focal spot velocities with a nearly constant peak intensity over 4.5 mm. Experiments that increased the peak intensity above the ionization threshold for gas demonstrated ionization waves propagating at the velocity of the flying focus. These ionization waves of any velocity overcome several laser-plasma propagation issues, including ionization-induced refraction. The flying focus presents opportunities to overcome current fundamental limitations in laser-plasma amplifiers, laser wakefield accelerators, photon accelerators, and high-order frequency conversion. [ABSTRACT FROM AUTHOR]

The article provides information on the results of a survey conducted on the use of throat packs in neuroanaesthesia by the Neuroanaesthesia Society of Great Britain and Ireland. According to the survey, 49 percent of the anesthetists reported inserting a throat pack during neurosurgery, 30 percent for tracheal tube stabilization, 27 percent for the prevention of spillage of secretions and 18 percent for the minimization of airway soiling during trans-sphenoidal surgery.