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Time dependent changes in 13.5 nm extreme ultraviolet (EUV) reflectivity of Ru mirrors due to variations in surface composition were investigated. The surface properties of Ru films were analyzed in situ by means of X-ray photoelectron spectroscopy (XPS), and further verified by Auger electron spectroscopy (AES). Moreover, the impact on EUV reflectivity (EUVR) with time was examined in situ via continuous and/or discrete EUV exposures. The rapid decrease in EUVR was observed in the presence of photoelectrons (PEs) from Ru mirror of the EUV setup, whereas no significant variation was recorded by screening out additional PEs. Detailed XPS and AES analyses suggest that carbon deposition via dissociation of residual hydrocarbons plays a dominant role in the presence of additional PEs, and thus reduces the reflectivity rapidly. Using EUV photoelectron spectroscopy, systematic reduction of the secondary electron yield from the Ru mirror surface was observed in consecutive scans, and therefore supports the formation of carbonaceous Ru surface in the presence of additional PEs. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the study was to measure and compare national continuum of HIV care estimates in Europe and Central Asia in three key subpopulations: men who have sex with men (MSM), people who inject drugs (PWID) and migrants. Methods: Responses to a 2016 European Centre for Disease Prevention and Control (ECDC) survey of 55 European and Central Asian countries were used to describe continuums of HIV care for the subpopulations. Data were analysed using three frameworks: Joint United Nations Programme on HIV/AIDS (UNAIDS) 90‐90‐90 targets; breakpoint analysis identifying reductions between adjacent continuum stages; quadrant analysis categorizing countries using 90% cut‐offs for continuum stages. Results: Overall, 29 of 48 countries reported national data for all HIV continuum stages (numbers living with HIV, diagnosed, receiving treatment and virally suppressed). Six countries reported all stages for MSM, seven for PWID and two for migrants. Thirty‐one countries did not report data for MSM (34 for PWID and 41 for migrants). In countries that provided key‐population data, overall, 63%, 40% and 41% of MSM, PWID and migrants living with HIV were virally suppressed, respectively (compared with 68%, 65% and 68% nationally, for countries reporting key‐population data). Variation was observed between countries, with higher outcomes in subpopulations in Western Europe compared with Eastern Europe and Central Asia. Conclusions: Few reporting countries can produce the continuum of HIV care for the three key populations. Where data are available, differences exist in outcomes between the general and key populations. While MSM broadly mirror national outcomes (in the West), PWID and migrants experience poorer treatment and viral suppression. Countries must develop continuum measures for key populations to identify and address inequalities. [ABSTRACT FROM AUTHOR]

Irrigation scheduling tools are critical to allow producers to effectively manage water resources for crop production. To be useful, these tools need to be accurate, complete, and relatively reliable. The current work presents an uncertainty analysis and its results for the Mississippi Irrigation Scheduling Tool (MIST) model, showing the margin of error (uncertainty) of the resulting irrigation advice arising solely from the propagation of measurement uncertainty through the MIST calculations. The final relative uncertainty in the water balance value from MIST was shown to be around 9% of that value, which is in the normal range of the margin of error and acceptable for agronomic systems. The results of this research also indicate that accurate measurements of irrigation and rainfall are critical to minimizing errors when using MIST and similar scheduling tools. While developed with data from Mississippi, the results of this uncertainty analysis are relevant to similar tool development efforts across the southern and southeastern United States and other high-rainfall areas, especially for locations lacking high-quality co-located weather stations. [ABSTRACT FROM AUTHOR]

With the long-term goal of developing a gene-based treatment for osteoarthritis (OA), we performed studies to evaluate the equine joint as a model for adeno-associated virus (AAV)-mediated gene transfer to large, weight-bearing human joints. A self-complementary AAV2 vector containing the coding regions for human interleukin-1-receptor antagonist (hIL-1Ra) or green fluorescent protein was packaged in AAV capsid serotypes 1, 2, 5, 8 and 9. Following infection of human and equine synovial fibroblasts in culture, we found that both were only receptive to transduction with AAV1, 2 and 5. For these serotypes, however, transgene expression from the equine cells was consistently at least 10-fold higher. Analyses of AAV surface receptor molecules and intracellular trafficking of vector genomes implicate enhanced viral uptake by the equine cells. Following delivery of 1 × 1011 vector genomes of serotypes 2, 5 and 8 into the forelimb joints of the horse, all three enabled hIL-1Ra expression at biologically relevant levels and effectively transduced the same cell types, primarily synovial fibroblasts and, to a lesser degree, chondrocytes in articular cartilage. These results provide optimism that AAV vectors can be effectively adapted for gene delivery to large human joints affected by OA. [ABSTRACT FROM AUTHOR]

We investigated the role of prepulse laser wavelength on extreme-ultraviolet (EUV) emission and ionic debris generation. A 6 ns Nd:YAG laser operating at 266 nm was used to generate a pre-plasma that was then reheated by a 35 ns CO laser pumping pulse at 10.6 μm. At an ideal delay time, improvement in EUV conversion efficiency (CE) of up to 30 % was seen compared to the CE from the pumping pulse alone. It was also shown that the most probable Sn ion kinetic energies were reduced significantly with the use of a prepulse, however, ion fluence increased. These results were compared to those obtained using a 1064 nm prepulse. [ABSTRACT FROM AUTHOR]

Objective Effective antiretroviral therapy (ART) has transformed the care of people with HIV, but it is important to monitor time trends in indicators of treatment success and antic future changes. Methods We assessed time trends from 2000 to 2007 in several indicators of treatment success in the UK Collaborative HIV Cohort (CHIC) Study, and using national HIV data from the Health Protection Agency (HPA) we developed a model to project future trends. Results The proportion of patients on ART with a viral load <50 HIV-1 RNA copies/mL increased from 62% in 2000 to 84% in 2007, and the proportion of all patients with a CD4 count <200 cells/μL decreased from 21% to 10%. During this period, the number of patients who experienced extensive triple class failure (ETCF) rose from 147 (0.9%) to 1771 (3.9%). The number who experienced such ETCF and had a current viral load >50 copies/mL rose fromz 118 (0.7%) to 857 (1.9%). Projections to 2012 suggest sustained high levels of success, with a continued increase in the number of patients who have failed multiple drugs but a relatively stable number of such patients experiencing viral loads >50 copies/mL. Numbers of deaths are projected to remain low. Conclusions There have been continued improvements in key indicators of success in patients with HIV from 2000 to 2007. Although the number of patients who have ETCF is projected to rise in the future, the number of such patients with viral loads >50 copies/mL is not projected to increase up to 2012. New drugs may be needed in future to sustain these positive trends. [ABSTRACT FROM AUTHOR]

Because of the increased interest in miscanthus as a new source of biomass for energy production and fibre, in 2007 a field experiment was established to determine the optimum storage conditions for miscanthus in round bale form (1.2m diameter×1.2m long). Miscanthus bales were stored under three treatments, outdoor uncovered, outdoor covered and indoor. The miscanthus bales were selected from three stands at three initial moisture conditions (13%, 32% and 39%) wet basis (wb). The storage trial was arranged in a 3×3 factorial experiment with two replicates laid out as a completely randomised design. Bale percent moisture content was repeatedly measured. Uncovered bales stored outdoors gained on average 24% moisture (wb), with resultant degradation of the material quality. Bales stored outdoors covered or indoors lost on average 4.3% and 6.8% moisture (wb) respectively. The energy content of bales stored outdoors uncovered was considerably lower than that of bales stored outdoors covered or indoors. The average lower heating value (LHV) of bales stored outdoors uncovered was 9.34MJkg−1 compared to a LHV 15.33MJkg−1 for bales under covered storage. It is concluded that miscanthus bales must be stored under cover either indoors or outdoors using plastic or tarpaulins to prevent deterioration of the bales and for drying to occur. [Copyright &y& Elsevier]

Objective The aim of the study was to describe the characteristics of young people with vertically acquired HIV diagnosed aged ≥13 years. Methods A retrospective review of HIV diagnoses reported to well-established national paediatric and adult HIV surveillance systems in the United Kingdom/Ireland was conducted. Results Forty-two young people with vertically acquired HIV diagnosed aged ≥13 years were identified; 23 (55%) were female, 40 (95%) were black African and 36 (86%) were born in sub-Saharan Africa. The median age at HIV diagnosis was 14 years (range, 13–20 years). Half of the patients presented with symptoms; the remainder were screened for HIV following diagnosis of a relative. The median CD4 count at diagnosis was 210 cells/μL (range, 0–689 cells/μL), 12 patients (29%) were diagnosed with AIDS at HIV diagnosis or subsequently, and 34 (81%) started combination antiretroviral therapy (ART), most (31 of 34) within a year of diagnosis. Conclusion A small number of young people with vertically acquired HIV survive childhood without ART and are diagnosed at age ≥13 years in the United Kingdom/Ireland. Half of the patients were asymptomatic, highlighting the importance of considering HIV testing for all offspring of HIV-infected women, regardless of age or symptoms. Increased awareness among clinicians and parents is required to reduce delayed presentation with advanced disease and to avoid onward transmission as these young people become sexually active. [ABSTRACT FROM AUTHOR]

This study involved an evaluation of the changes in grain yield, nutritive value, ensilability and harvesting losses of intensively managed winter cereals harvested during the advancing stages of ripening. Five cereal crops (barley cv. Regina and wheat cv. Madrigal in 2001; barley cv. Regina, wheat cv. Falstaff and triticale cv. Fidelio in 2002) were assessed. Twenty plots per crop were arranged in a randomised complete block design, with five times of harvest (four for barley in 2002) and four replicate blocks per harvest. Dry matter (DM) yields changed relatively little between harvest dates, but fresh yields declined (P < 0.001) over time due to the moisture loss associated with ripening. Time-course changes in indices of nutritive value, such as concentrations of crude protein, starch and ash, and organic matter digestibility, were relatively small and did not follow a consistent pattern. Ensilability indices, such as DM and water-soluble carbohydrate concentrations and buffering capacity, indicated that satisfactory fermentations were likely if such crops were ensiled; buffering capacity, generally declining with advancing maturity. Harvesting losses were not clearly related to growth stage at harvest. It is concluded that winter cereal grain (barley, wheat and triticale) DM yields and quality were relatively constant as ripening progressed from DM concentrations of around 550 to >800 g/kg. [ABSTRACT FROM AUTHOR]

Laser-produced plasma (LPP) devices have been modeled as the light source for extreme ultraviolet (EUV) lithography. A key challenge for LPP is achieving sufficient brightness to support the throughput requirements of high-volume manufacturing. An integrated model (HEIGHTS) was applied to simulate the environment of EUV sources and optimize their output. The model includes plasma evolution and magnetohydrodynamic processes in a two-temperature approximation, as well as photon radiation transport determined by the Monte Carlo method. It uses the total variation diminishing scheme for the description of magnetic compression and diffusion in a cylindrical 2-D geometry for the target. Generation of the internal magnetic field with nonparallel density and temperature gradients was also considered. Preliminary results from numerical simulation in hydrodynamics and line radiation output of xenon and tin plasmas are presented for planar and droplet targets. [ABSTRACT FROM AUTHOR]

Primary and secondary prevention are essential components of the response to HIV and sexually transmitted infections (STIs). We present findings from nationally implemented HIV/STI prevention interventions. In 2003, of those attending STI clinics at least 64% of men who have sex with men (MSM) and 55% of heterosexuals accepted a confidential HIV test; 88% of all HIV infections in women giving birth in England were diagnosed before delivery; 85% of MSM eligible for hepatitis B vaccination received a first dose of vaccine at their first STI clinic attendance; 74% of STI clinic attendees for emergency appointments, and 20% of those for routine appointments were seen within 48 hours of initiating an appointment; the National Chlamydia Screening Programme in England found a positivity of 10% and 13% among young asymptomatic women and men, respectively. Prevention initiatives have seen recent successes in limiting further HIV/STI transmission. However, more work is required if current levels of transmission are to be reduced. [ABSTRACT FROM AUTHOR]

Nonideal effects in the optical train of the motional Stark effect diagnostic have been modeled using the Mueller matrix formalism. The effects examined are birefringence in the vacuum windows, an imperfect reflective mirror, and signal pollution due to the presence of a circularly polarized light component. Relations for the measured intensity ratio are developed for each case. These relations suggest fitting functions to more accurately model the calibration data. One particular function, termed the tangent offset model, is found to fit the data for all channels better than the currently used tangent slope function. Careful analysis of the calibration data with the fitting functions reveals that a nonideal effect is present in the edge array and is attributed to nonideal performance of a mirror in that system. The result of applying the fitting function to the analysis of our data has been to improve the equilibrium reconstruction. [ABSTRACT FROM AUTHOR]

Objectives: To examine trends in rates of diagnoses of HIV and other sexually transmitted infections (STIs) in men who have sex with men (MSM) in England and Wales between 1997 and 2002. Methods: Estimates of the MSM population living in England and Wales, London and the rest of England and Wales were applied to surveillance data, providing rates of diagnoses of HIV and STIs and age group specific rates for HIV and uncomplicated gonorrhoea. Results: Between 1997 and 2002, rates of diagnoses of HIV and acute STIs in MSM increased substantially. Rates in London were higher than elsewhere. Rises in acute STIs were similar throughout England and Wales, except for uncomplicated gonorrhoea and infectious syphilis, with greater increases outside London. Rates of gonorrhoea diagnoses doubled between 1999 and 2001 (661/100 000, 1271/100 000, p<0.001) in England and Wales followed by a slight decline to 1210/100 000 (p=0.03) in 2002—primarily the result of a decline in diagnoses among men aged 25-34 (1340/100 000, 1128/ 100 000, p<0.001} and 35-44 (924/100 000, 863/100 000, p=0.03) in London. HIV was the third most common STI diagnosed in MSM in England and Wales and the second in London, with the highest rate (1286/100 000) found among men aged 35-44 in London in 2002. Conclusions: Rates of diagnosis of HIV and other STIs have increased substantially among MSM in England and Wales. Increases show heterogeneity by infection, geography, and age over time. Rates in London were twice those seen elsewhere, with greatest changes over time. The observed changes reflect concomitant increases in high risk behaviour documented in behavioural surveillance survey programmes. [ABSTRACT FROM AUTHOR]

: BackgroundClinical trials indicate that electroconvulsive therapy (ECT) is the most effective treatment for major depression, but its effectiveness in community settings has not been examined.: MethodsIn a prospective, naturalistic study involving 347 patients at seven hospitals, clinical outcomes immediately after ECT and over a 24-week follow-up period were examined in relation to patient characteristics and treatment variables.: ResultsThe sites differed markedly in patient features and ECT administration but did not differ in clinical outcomes. In contrast to the 70%–90% remission rates expected with ECT, remission rates, depending on criteria, were 30.3%–46.7%. Longer episode duration, comorbid personality disorder, and schizoaffective disorder were associated with poorer outcome. Among remitters, the relapse rate during follow-up was 64.3%. Relapse was more frequent in patients with psychotic depression or comorbid Axis I or Axis II disorders. Only 23.4% of ECT nonremitters had sustained remission during follow-up.: ConclusionsThe remission rate with ECT in community settings is substantially less than that in clinical trials. Providers frequently end the ECT course with the view that patients have benefited fully, yet formal assessment shows significant residual symptoms. Patients who do not remit with ECT have a poor prognosis; this underscores the need to achieve maximal improvement with this modality. [Copyright &y& Elsevier]

Adequate nutrition is critical during long-term spaceflight, as is the ability to easily monitor dietary intake. A comprehensive nutritional status assessment profile was designed for use before, during and after flight. It included assessment of both dietary intake and biochemical markers of nutritional status. A spaceflight food-frequency questionnaire (FFQ) was developed to evaluate intake of key nutrients during spaceflight. The nutritional status assessment protocol was evaluated during two ground-based closed-chamber studies (60 and 91 d; n = 4/study), and was implemented for two astronauts during 4-mo stays on the Mir space station. Ground-based studies indicated that the FFQ, administered daily or weekly, adequately estimated intake of key nutrients. Chamber subjects maintained prechamber energy intake and body weight. Astronauts tended to eat 40--50% of WHO-predicted energy requirements, and lost >10% of preflight body mass. Serum ferritin levels were lower after the chamber stays, despite adequate iron intake. Red blood cell folate concentrations were increased after the chamber studies. Vitamin D stores were decreased by > 40% on chamber egress and after spaceflight. Mir crew members had decreased levels of most nutritional indices, but these are difficult to interpret given the insufficient energy intake and loss of body mass. Spaceflight food systems can provide adequate intake of macronutrients, although, as expected, micronutrient intake is a concern for any closed or semiclosed food system. These data demonstrate the utility and importance of nutritional status assessment during spaceflight and of the FFQ during extended-duration spaceflight. [ABSTRACT FROM AUTHOR]

The specific size and structure of the edge current profile has important effects on the magnetohydrodynamic stability and ultimate performance of many advanced tokamak (AT) operating modes. This is true for both bootstrap and externally driven currents that may be used to tailor the edge shear. Absent a direct local measurement of j(r), the best alternative is a determination of the poloidal field. Measurements of the precision (0.1°–0.01° in magnetic pitch angle and 1–10 ms) necessary to address issues of stability and control and provide constraints for EFIT are difficult to do in the region of interest (ρ=0.9–1.1). Using Zeeman polarization spectroscopy of the 2S–2P lithium resonance line emission from the DIII-D LIBEAM [D. M. Thomas, Rev. Sci. Instrum. 66, 806 (1995); D. M. Thomas, A. W. Hyatt, and M. P. Thomas, Rev. Sci. Instrum. 61, 340 (1990)] measurements of the various field components may be made to the necessary precision in exactly the region of interest to these studies. Because of the negligible Stark mixing of the relevant atomic levels, this method of determining j(r) is insensitive to the large local electric fields typically found in enhanced confinement (H mode) edges, and thus avoids an ambiguity common to motional Stark effect measurements of B. Key issues for utilizing this technique include good beam quality, an optimum viewing geometry, and a suitable optical prefilter to isolate the polarized emission line. A prospective diagnostic system for the DIII-D AT program will be described. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Examines the impurity-induced turbulence suppression and reduced transport in the DIII-D tokamak. Effect of neon seeding of a low confinement mode negative central shear discharge; Use of beam emission spectroscopy; Reduction in growth rate of ion temperature gradient driven modes.

The amplitude and frequency of modes driven in the edge region of tokamak high mode (H-mode) discharges [type I edge-localized modes (ELMs)] are shown to depend on the discharge shape. The measured pressure gradient threshold for instability and its scaling with discharge shape are compared with predictions from ideal magnetohydrodynamic theory for low toroidal mode number (n) instabilities driven by pressure gradient and current density and good agreement is found. Reductions in mode amplitude are observed in discharge shapes with either high squareness or low triangularity where the stability threshold in the edge pressure gradient is predicted to be reduced and the most unstable mode is expected to have higher values of n. The importance of access to the ballooning mode second stability regime is demonstrated through the changes in the ELM character that occur when second regime access is not available. An edge stability model is presented that predicts that there is a threshold value of n for second regime access and that the most unstable mode has n near this threshold. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In DIII-D [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)] tokamak plasmas with an internal transport barrier (ITB), the comparison of gyrokinetic linear stability (GKS) predictions with experiments in both low and strong negative magnetic shear plasmas provide improvedunderstanding for electron thermal transport within the plasma. Within a limited region just inside the ITB, the electron temperature gradient (ETG) modes appear to control the electron temperature gradient and, consequently, the electron thermal transport. The increase in the electron temperature gradient with more strongly negative magnetic shear is consistent with the increase in the ETG mode marginal gradient. Closer to the magnetic axis the T3 profile flattens and the ETG modes are predicted to be stable. With additional core electron heating, FIR scattering measurements near the axis show the presence of high k fluctuations (12 cm-1), rotating in the electron diamagnetic drift direction. This turbulence could impact electron transport and possibly also ion transport. Thermal diffusivities for electrons, and to a lesser degree ions, increase. The ETG mode can exist at this wave number, but it is computed to be robustly stable near the axis. Consequently, in the plasmas we have examined, calculations of drift wave linear stability do not explain the observed transport near the axis in plasmas with or without additional electron heating, and there are probably other processes controling transport in this region.. [ABSTRACT FROM AUTHOR]

One promising approach to maintaining stability of high beta tokamak plasmas is the use of a conducting wall near the plasma to stabilize low-n ideal magnetohydrodynamic instabilities. However, with a resistive wall, either plasma rotation or active feedback control is required to stabilize the more slowly growing resistive wall modes (RWMs). Previous experiments have demonstrated that plasmas with a nearby conducting wall can remain stable to the n=1 ideal external kink above the beta limit predicted with the wall at infinity. Recently, extension of the wall stabilized lifetime τL to more than 30 times the resistive wall time constant τw and detailed, reproducible observation of the n=1 RWM have been possible in DIII-D [Plasma Physics and Controlled Fusion Research (International Atomic Energy Agency, Vienna, 1986), p. 159] plasmas above the no-wall beta limit. The DIII-D measurements confirm characteristics common to several RWM theories. The mode is destabilized as the plasma rotation at the q=3 surface decreases below a critical frequency of 1?7 kHz (˜1% of the toroidal Alfvén frequency). The measured mode growth times of 2?8 ms agree with measurements and numerical calculations of the dominant DIII-D vessel eigenmode time constant τw . From its onset, the RWM has little or no toroidalrotation (ωmode≤τw-1«ωplasma), and rapidly reduces the plasma rotation to zero. These slowly growing RWMs can in principle be destabilized using external coils controlled by a feedback loop. In this paper, the encouraging results from the first open loop experimental tests of active control of the RWM, conducted in DIII-D, are reported. [ABSTRACT FROM AUTHOR]

Abstract: In extreme ultraviolet lithography (EUVL) environments, transient plasma dynamics dictate conditions for particle/surface interactions. A critical challenge facing EUVL development is optical component lifetime in both gas-discharge-produced plasmas (DPP) and laser-produced plasma (LPP) devices. Optical components are exposed to impinging fast ions and neutrals, impurities (H, C, O, N) and debris, leading to component degradation and consequently limiting 13.5-nm light reflection intensity. This paper studies Xe+ irradiation-induced mechanisms that affect the performance of EUVL multilayer collector mirror surfaces. Irradiation conditions include: incident particle energies of 1keV and 5keV, Xe+ fluences ranging from about 3×1014–5×1016 Xe+/cm2 and surface temperatures of 273K and 473K. Measurements include in situ quartz crystal microbalance for sputtering rate measurements, ion scattering spectroscopy, X-ray reflectivity and atomic force microscopy. Three distinct erosion regimes for bombardment of MLM with Xe+ are: a low Xe+ fluence regime below ∼5×1014 Xe+/cm2, a moderate regime at fluences between 5×1014 and 5×1016 Xe+/cm2 and a high fluence regime >1017 Xe+/cm2. [Copyright &y& Elsevier]

In the microwave tokamak experiment (MTX) program, we are concentrating on experiments using intense, free-electron laser (FEL) generated microwave pulses. In initial FEL experiments, several diagnostic instruments were operated during injection of microwave pulses with peak powers to 0.2 GW at durations of 10 ns. Fixed and spatially scanning microwave detectors and receivers and a 48-element calorimeter on the inside walt of MTX diagnosed the GW-level FEL microwave pulses. With these diagnostics, linear-wave absorption and efficiencies of transmission through the quasi-optical transport system were studied. In addition, several radially resolved measurements of plasma density, temperature, and emission were made during FEL injection and were used in the analysis of microwave absorption data. A timing system, slaved to the FEL pulse arrival time, is capable of accuracy to a few nanoseconds in order to allow measurement of heating effects on the time scale of a single FEL pulse. [ABSTRACT FROM AUTHOR]

The use of a 0.185-mm far-infrared (FIR) laser interferometer on MTX required the design and development of optical components which are nonmagnetic and nonconducting. This arose from the requirement that the path length of the FIR interferometer not change by more than 1/50 of a wavelength during the half-second plasma pulse. The time-dependent stray magnetic fields, 7000-400 G over the optical table area, generate strong eddy current forces which would produce path length changes greater than the design criteria if the components were metallic. Thus, the optical tower which supports the optical tables, one above and one below the tokamak, is a composite structure of 304 stainless steel and G-10 fiberglass. Also, the optical table and components are made of G-10 with a minimum of 304 stainless-steel parts to avoid eddy current forces and maintain structural rigidity. The design criteria of the optical components are discussed with a comparison of suitable materials. A discussion of the process which was developed to fabricate plastic parabolic beam expanding and focusing mirrors with a metallized reflective surface is presented. The mixer and electronics enclosure design minimizes eddy current forces by use of printed circuit board material while maintaining excellent EMI/RFI shielding. [ABSTRACT FROM AUTHOR]

Elastic and inelastic differential cross sections for neutron scattering from 56Fe have been measured for several incident energies from 1.30 to 7.96 MeV at the University of Kentucky Accelerator Laboratory. Scattered neutrons were detected using a C6D6 liquid scintillation detector using pulse-shape discrimination and time-of-flight techniques. The deduced cross sections have been compared with previously reported data, predictions from evaluation databases ENDF, JENDL, and JEFF, and theoretical calculations performed using different optical model potentials using the talys and empire nuclear reaction codes. The coupled-channel calculations based on the vibrational and soft-rotor models are found to describe the experimental (n,n0) and (n,n1) cross sections well. [ABSTRACT FROM AUTHOR]

Nonlinear simulations of experimentally observed magnetohydrodynamic (MHD) bursts in DIII-D [J. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)] L-mode negative central magnetic shear (NCS) discharges were performed with a full three-dimensional nonlinear MHD code. The effects of plasma rotation in the presence of resistivity and viscosity are included and an effectively implicit numerical scheme allows the transport profile to evolve self-consistently with the nonlinear MHD instabilities and externally applied sources and sinks. The simulations follow the MHD bursts and disruptions through the linear and nonlinear phases and identify the connections between the early MHD bursts and the ultimate disruption phase. Specific predictions of the growth and saturation of the modes are directly compared with experimental diagnostic measurements in DIII-D. The simulations show that the bursts observed in experiments are triggered by MHD instability of a resistive interchange mode and a resistive kink mode that are excited for critical plasma profiles. The critical profiles are determined by the balance between inductive and noninductive sources of current density. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Sawtooth phenomena have been studied on DIII-D and the Tokamak Fusion Test Reactor (TFTR) [D. Meade and the TFTR Group, in Proceedings of the International Conference on Plasma Physics and Controlled Nuclear Fusion, Washington, DC, 1990 (International Atomic Energy Agency, Vienna, 1991), Vol. 1, pp. 9-24]. In the experiments the sawtooth characteristics were studied with fast electron temperature (ECE) and soft x-ray diagnostics. For the first time, measurements of a strong ballistic electron heat pulse were made in a shaped tokamak (DIII-D) [J. Luxon and DIII-D Group, in Proceedings of the 11th International Conference on Plasma Physics and Controlled Nuclear Fusion Research, Kyoto (International Atomic Energy Agency, Vienna, 1987), Vol. 1, p. 159] and the "ballistic effect" was stronger than was previously reported on TFTR. Evidence is presented in this paper that the ballistic effect is related to the fast growth phase of the sawtooth precursor. Fast, 2 ms interval, measurements on DIII-D were made of the ion temperature evolution following sawteeth and partial sawteeth to document the ion heat pulse characteristics. It is found that the ion heat pulse does not exhibit the very fast, "ballistic" behavior seen for the electrons. Further, for the first time it is shown that the electron heat pulses from partial sawtooth crashes (on DIII-D and TFTR) are seen to propagate at speeds close to those expected from the power balance calculations of the thermal diffusivities whereas heat pulses from fishbones propagate at rates more consistent with sawtooth induced heat pulses. These results suggest that the fast propagation of sawtooth-induced heat pulses is not a feature of nonlinear transport models, but that magnetohydrodynamic events can have a strong effect on electron thermal transport. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Background: Informal caregivers contribute substantially to the self-care of people with heart failure (HF) by helping with concrete and interpersonal tasks. Time perception and management are essential issues among caregivers. However, investigators have not explored this topic in caregivers of people with HF., Objectives: The aim of this study was to describe the perceptions and challenges of the time management experience among caregivers who support the self-care efforts of their relatives with HF., Methods: Adult informal caregivers of patients with HF, taking care of the patient for at least 3 months and without cognitive limitations, were recruited from Spain, Italy, and the Netherlands. Data were collected using semistructured interviews. Maryring's qualitative content analysis strategy with both a deductive and an inductive approach was used for analysis., Results: We enrolled 50 participants (20 Italians, 19 Spanish, and 11 Dutch). Caregivers had a mean (SD) age of 62.8 (12.8) years and were mostly female (84%). They dedicated 31.2 (SD, 21.7) hours per week to providing caring activities for their patients. After extracting 33 codes from their qualitative interview data, we summarized them into 8 categories and identified 4 main themes: (1) time for yourself, (2) house management, (3) time for the patient (dedicated to directing care), and (4) time for own socialization., Conclusion: Caregivers navigate the complexity of time management by balancing dedicated time for supporting patients with HF and their own personal time., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

International migrants, especially those belonging to key populations, face a considerable HIV burden. However, continuity of HIV care for this group is often challenged along the migration route. We assess the available evidence on the existing interventions that aim to strengthen community and health systems to ensure the continuity of HIV care for international migrants. We did a systematic search of PubMed for publications from 1989 until 2023 focused on different stages of the HIV care continuum regardless of the geographical region. The literature was reviewed with a thematic approach. Globally, legal regulations can restrict access to HIV care and fuel fear of deportation among undocumented migrants. The intersection of HIV-related and migration-related stigma creates further challenges for uninterrupted access to HIV care along the migration route, with negative clinical and public health consequences. Different potential interventions were identified including: provision of HIV care regardless of migration status; utilisation of mobile health, mobile units, and community-led initiatives to bring HIV care to migrants; and utilisation of participatory and co-creation methods to develop tailored and sustainable HIV-related interventions with migrant communities. Improving access to the continuity of care for migrants requires a shift towards intersectional policies rooted in co-creation approaches to address the underlying multiple and mutually reinforcing inequalities., Competing Interests: Declaration of interests We declare no competing interests. The views and opinions expressed herein are the authors' own and do not necessarily state or reflect those of ECDC. ECDC is not responsible for the data and information collation and analysis and cannot be held liable for conclusions or opinions drawn., (Copyright © 2024 Elsevier Ltd. All rights reserved, including those for text and data mining, AI training, and similar technologies.)

Competing Interests: We have read the journal's policy and the authors of this manuscript have the following competing interests to declare: Forum for Collaborative Research, as an organization, receives grants from the pharmaceutical industry but these are unrestricted and not specific to the work described in this article. KHM has received unrestricted research grants from Gilead Sciences, Merck & Co., Inc., and ViiV Healthcare. JM is a paid consultant for both Gilead Sciences in the area of HIV prevention. BSP, as an inventor of the LAg-Avidity EIA at CDC, receives a portion of the royalties from the sale of the test kits, as per policy of the U.S. government. MNR received consulting fees from the Bill and Melinda Gates Foundation, Merck, the Forum for Collaborative research, and the International AIDS Vaccine Initiative in 2024. VV is a full-time employee of ViiV Healthcare and owns GSK stock. HYL received NIH NIAID grant support for genomic HIV incidence assay research. All other authors have declared that no competing interests exist.

Background: Key population HIV programmes in sub-Saharan Africa require epidemiological information to ensure equitable and universal access to effective services. We aimed to consolidate and harmonise survey data among female sex workers, men who have sex with men, people who inject drugs, and transgender people to estimate key population size, HIV prevalence, and antiretroviral therapy (ART) coverage for countries in mainland sub-Saharan Africa., Methods: Key population size estimates, HIV prevalence, and ART coverage data from 39 sub-Saharan Africa countries between 2010 and 2023 were collated from existing databases and verified against source documents. We used Bayesian mixed-effects spatial regression to model urban key population size estimates as a proportion of the gender-matched, year-matched, and area-matched population aged 15-49 years. We modelled subnational key population HIV prevalence and ART coverage with age-matched, gender-matched, year-matched, and province-matched total population estimates as predictors., Findings: We extracted 2065 key population size data points, 1183 HIV prevalence data points, and 259 ART coverage data points. Across national urban populations, a median of 1·65% (IQR 1·35-1·91) of adult cisgender women were female sex workers, 0·89% (0·77-0·95) were men who have sex with men, 0·32% (0·31-0·34) were men who injected drugs, and 0·10% (0·06-0·12) were women who were transgender. HIV prevalence among key populations was, on average, four to six times higher than matched total population prevalence, and ART coverage was correlated with, but lower than, the total population ART coverage with wide heterogeneity in relative ART coverage across studies. Across sub-Saharan Africa, key populations were estimated as comprising 1·2% (95% credible interval 0·9-1·6) of the total population aged 15-49 years but 6·1% (4·5-8·2) of people living with HIV., Interpretation: Key populations in sub-Saharan Africa experience higher HIV prevalence and lower ART coverage, underscoring the need for focused prevention and treatment services. In 2024, limited data availability and heterogeneity constrain precise estimates for programming and monitoring trends. Strengthening key population surveys and routine data within national HIV strategic information systems would support more precise estimates., Funding: UNAIDS, Bill & Melinda Gates Foundation, and US National Institutes of Health., Competing Interests: Declaration of interests SB has received funding from the US National Institutes of Health (NIH). FC has received funding from the Wellcome Trust, the Medical Research Council, NIH, Unitaid, and the Bill & Melinda Gates Foundation. LD has received untied educational grants for the study of new opioid medications in Australia from Indivior and Sequirus. EF has received funding from the UK Research and Innovation Medical Research Council, the Royal Society, and the Centre for Sexual Health and HIV/AIDS Research Zimbabwe. JWI-E acknowledges funding from UNAIDS, NIH, the Gates Foundation, UK Research and Innovation, and BAO Systems, and has received support to attend meetings from UNAIDS, the South African Centre for Epidemiological Modelling and Analysis, the International AIDS Society, and the Gates Foundation. KR and MM-G have received support to attend meetings from UNAIDS. JS has received funding from UNAIDS. OS has received funding from UNAIDS. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

The World Health Organization recommends that all blood donations be screened for transfusion transmissible infections; these data are currently not incorporated into national disease surveillance efforts. We set out to use routinely collected data from blood donors in Blantyre district, Malawi to explore HIV and syphilis prevalence and identify sero-conversions among repeat donors. We conducted a retrospective cohort analysis of blood donation data collected by the Malawi Blood Transfusion Service from 2015 to 2021. All blood donations were routinely screened for HIV and syphilis. We characterized donor demographics as well as screening outcomes, including identifying sero-conversions among repeat donors who previously tested negative on their last donation. A total of 23,280 donations from 5,051 donors were recorded, with a median frequency of donations of 3 (IQR:2-6). Most donors were male (4,294; 85%) and students (3,262; 64.6%). Prevalence of HIV at first donation was 1.0% (52/5,051) and prevalence of syphilis was 1.6% (80/5,051); 52 HIV sero-conversions and 126 syphilis sero-conversions were identified, indicating an incidence rate per 1,000 person-years of 5.9 (95% CI: 4.7, 7.4) and 13.3 (95% CI:11.4, 15.4) respectively. Students had a lower prevalence of HIV and syphilis but higher risk of syphilis seroconversion. While blood donors are generally considered a low-risk population for HIV and syphilis, we were able to identify relatively high rates of undiagnosed HIV and syphilis infections among donors. Routinely collected data from national blood donation services may be used to better understand local HIV and syphilis epidemiology, with the potential to enhance disease surveillance systems. These findings may be used to identify priority prevention areas and populations in Blantyre district that can inform targeted interventions for improved disease prevention, testing and treatment., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Singogo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Women who engage in sex work in sub-Saharan Africa have a high risk of acquiring HIV infection. HIV incidence has declined among all women in sub-Saharan Africa, but trends among women who engage in sex work are poorly characterised. We synthesised data on HIV incidence among women who engage in sex work in sub-Saharan Africa and compared these with the total female population to understand relative incidence and trends over time., Methods: We searched MEDLINE, Embase, Global Health, and Google Scholar from Jan 1, 1990, to Feb 28, 2024, and grey literature for studies that reported empirical estimates of HIV incidence among women who engage in sex work in any sub-Saharan Africa country. We calculated incidence rate ratios (IRRs) compared with total female population incidence estimates matched for age, district, and year, did a meta-analysis of IRRs, and used a continuous mixed-effects model to estimate changes in IRR over time., Findings: From 32 studies done between 1985 and 2020, 2194 new HIV infections were observed among women who engage in sex work over 51 490 person-years. Median HIV incidence was 4·3 per 100 person years (IQR 2·8-7·0 per 100 person-years). Incidence among women who engage in sex work was eight times higher than matched total population women (IRR 7·8 [95% CI 5·1-11·8]), with larger relative difference in western and central Africa (19·9 [9·6-41·0]) than in eastern and southern Africa (4·9 [3·4-7·1]). There was no evidence that IRRs changed over time (IRR per 5 years: 0·9 [0·7-1·2])., Interpretation: Across sub-Saharan Africa, HIV incidence among women who engage in sex work remains disproportionately high compared with the total female population. However, constant relative incidence over time indicates HIV incidence among women who engage in sex work has declined at a similar rate. Location-specific data for women who engage in sex work incidence are sparse, but improved surveillance and standardisation of incidence measurement approaches could fill these gaps. Sustained and enhanced HIV prevention for women who engage in sex work is crucial to address continuing inequalities and ensure declines in new HIV infections., Funding: Bill & Melinda Gates Foundation, UK Research and Innovation, National Institutes of Health., Translation: For the French translation of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)