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OBJECTIVES/SPECIFIC AIMS: Our primary objective was to understand the relationship between incident or recent stressful events and adherence to HIV care in the context of other person, environment, and HIV-specific stressors in a sample of Black women living with HIV (WLWH). METHODS/STUDY POPULATION: Thirty in-depth interviews were conducted with Black women living with HIV who receive care at an academic HIV primary care clinic in the Southern region of the United States to elicit stressful events influencing adherence to HIV care. Semi-structured interview guides were used to facilitate discussion regarding stressful events and adherence to HIV care. Interviews were audiotaped and transcribed verbatim. Transcripts were independently coded using a theme-based approach by two experienced coders, findings were compared, and discrepancies were resolved by discussion. RESULTS/ANTICIPATED RESULTS: Participants described frequently experiencing incident stressful events including death or serious illness of a close friend or family member, and relationship, financial, and employment difficulties. Furthermore, participants reported experiencing traumatic events such as sexual and physical abuse during childhood and adolescents. While experiencing traumatic events such as sexual and physical abuse during childhood and adolescence may be distressing, these events did not influence adherence to HIV care. However, incident stressful events as defined above did influence adherence to HIV care for some participants, but not for others. For participants who reported that stressful events did not influence adherence to HIV care, factors such as personal motivation, access to social support, and adaptive coping strategies facilitated their engagement in care. DISCUSSION/SIGNIFICANCE OF IMPACT: Experiencing stressful events, incident or traumatic, is common among Black WLWH and have the potential to negatively influence adherence to HIV care. Thus, Interventions aimed at identifying and addressing stress, social support, and coping are essential to improve adherence to HIV care behaviors.
Numerous experimental studies have documented that injecting low-salinity water into an oil reservoir can increase the amount of oil recovered. However, owing to the complexity of the chemical interactions involved in this process, there has been much debate over the dominant mechanism causing this effect. In order to further understand one proposed mechanism, multicomponent ionic exchange, we study the motion of an oil slug through a clay pore throat filled with saline water. The pore throat is modelled as a capillary tube connecting two bulk regions of water. We assume that the surfaces of the oil and the capillary are negatively charged and that, due to repulsion between these surfaces, the oil slug is separated from the capillary surface by a thin film of water. Ion interactions at the oil–water and clay–water interfaces are modelled using the law of mass action. By using lubrication theory to describe the thin-film flow in the water layer separating the oil from the clay surface, and the macroscopic flow through the capillary, we derive expressions for the thickness of the wetting film, and the velocity of the oil slug, given a pressure difference across the ends of the capillary. Numerical results show that the thickness of the water layer and the velocity of the oil slug increase as the salinity of the water is reduced, suggesting that this mechanism contributes to the low-salinity effect. An analytical solution is presented in the limit in which the applied pressure is small.
In this paper, we report on an approach to estimate the contribution of Arctic glaciers to sea-level change. In our calculation we assume that a static approach is feasible. We only calculate changes in the surface balance from modelled sensitivities. These sensitivities, summarized in the seasonal sensitivity characteristic, can be used to calculate the change in the surface mass budget for given anomalies of monthly temperature and precipitation. We have based our calculations on a subdivision of all Arctic ice into 13 regions: four sectors of the Greenland ice sheet; the Canadian Arctic >74˚N; the Canadian Arctic <74˚N; Alaska, USA; Iceland; Svalbard; Zemlya Frantsa Iosifa, Russia; Novaya Zemlya, Russia; Severnaya Zemlya, Russia; and Norway/Sweden >60˚N. As forcing for the calculations, we have used the output from five climate models, for the period 2000–2100. These models were forced by the same greenhouse-gas scenario (IPCC-B2). The calculated contributions to sea-level rise in the year 2100 vary from almost zero to about 6 cm. The differences among the models stem first of all from differences in the precipitation. The largest contribution to sea-level change comes from the Greenland ice sheet. The glaciers in Alaska also make a large contribution, not because of the area they cover, but because they are more sensitive than other glaciers in the Arctic. The climate models do not agree on regional patterns. The runoff from Svalbard glaciers, for instance, increases for two models and decreases for the three other models. We conclude that the uncertainty due to a simple representation of the glaciological processes is probably smaller than the uncertainty induced by the differences in the climate-change scenarios produced by the models.
The last three years have witnessed a growing interest in the physical properties of the small bodies in the solar system. Perhaps the most significant impetus to research on small bodies has been the imminent arrival of Comet Halley in the inner solar system. This famous comet, which was recovered in autumn 1982, has been the object of intense study during the past year as it has approached the sun and developed a tail. Much of the international, ground-based astronomical research on Halley has been coordinated through the International Halley Watch program. Spacecraft from several nations have been successfully launched (or soon will be, we hope) and are on their way to intercept the comet and make close-up observations and in situ measurements. The commencement of spacecraft study of small bodies marks a new era in comet/asteroid science and, in coordination with ground-based and Earth-orbital observations, will result in unprecedented new knowledge about the origin of the solar system and about solar system processes. Although Halley is receiving the most attention, interest is also high in Comet Giacobini-Zinner, the vicinity of which will be probed by a diverted American spacecraft in September 1985. Upcoming spacecraft studies of comets through 1986 are described at the end of the comet section of this report. Asteroid exploration by spacecraft is also anticipated to begin in the near future. The trajectory of the NASA Gailieo Mission to Jupiter has been changed to permit close-encounter observations of the large main-belt asteroid 29 Amphitrite in December 1986; these observations will be conducted on a “best effort” basis only a few months after launch of Galileo. Interest is also high in Europe, the Soviet Union, and the United States in possible spacecraft missions to additional comets and asteroids during the 1990’s. If these efforts are pursued, there will be a concomitant ground-based effort. The last three years have also witnessed extremely productive efforts to observe small bodies from Earth orbit. For example, the Infrared Astronomical Satellite discovered a comet in 1983, which made the closest approach to the Earth of any comet in centuries. IRAS made important discoveries and measurements of other comets and also assembled an immense database on infrared brightnesses of thousands of numbered and unnumbered asteroids. The planned launch of the Hubble Space Telescope next year highlights the continuing potential for applying extremely powerful instrumental techniques to the study of comets and asteroids from above the Earth’s atmosphere.
The period covered by this report, 1984 July to 1987 June, was of extraordinary importance for the progress of cometary physics. For the first time in the history, special space probes were launched to comets. Vega 1, Vega 2 and Giotto encountered P/Halley, providing us with the first close-up pictures of a cometary nucleus, its surface features, and with the first in situ measurements of the matter escaping from it. ICE, Suisei and Sakigake carried out measurements relevant to P/Giacobini-Zinner and P/Halley in interplanetary space. Unprecedented worldwide campaigns of ground-based observations, with the participation of about 1000 professional and 2000 amateur astronomers, were coordinated in 8 sections of the International Halley Watch. Additional measurements were made from artificial satellites, sounding rockets, and highflying airplanes. The wealth of data collected in this way, to a major extent thanks to an excellent international cooperation, represents a milestone in cometary astronomy. Another important step was the progress in processing the extensive 1983 IRAS observations of minor planets and comets, including the discovery of asteroid dust bands and cometary dust trails.
III Zw 35 is a pair of galaxies characterised by intense OH maser emission, and powerful far-infrared and radio continuum. We have made a detailed study of the galaxy pair based on optical, infrared and radio observations. The brighter northern component is identified as a LINER or Seyfert galaxy and contains an active nuclear region from which radio continuum, OH maser and thermal dust emission are detected. We propose that the northern component has a compact active nucleus deeply embedded in an obscured region of diameter ~ 210 pc within which enhanced star-formation occurs. The lower luminosity, southern component is of low mass and is undergoing starburst activity over an extended region of diameter ~ 5.5 kpc. The origin of the starburst and non-thermal activity appears to be an interaction between the two components.
JET experiments have compared the efficacy of low- and high-field side ion cyclotron resonance heating (ICRH) as an actuator to deliberately minimise the sawtooth period. It is found that low-field side ICRH with low minority concentration is optimal for sawtooth control for two main reasons. Firstly, low-field side heating means that any toroidal phasing of the ICRH (
or dipole) has a destabilising effect on the sawteeth, meaning that dipole phasing can be employed, since this is preferable due to less plasma wall interaction from Resonant Frequency (RF) sheaths. Secondly, the resonance position of the low-field side ICRH does not have to be very accurately placed to achieve sawtooth control, relaxing the requirement for real-time control of the RF frequency. These empirical observations have been confirmed by hybrid kinetic–magnetohydrodynamic modelling, and suggest that the ICRH antenna design for ITER is well positioned to provide a control actuator capable of having a significant effect on the sawtooth behaviour.
Background: For adolescents with epilepsy, there is often a poor system in place to meet their individualized transition needs. Our objectives were 1) to develop epilepsy-specific transition care management plans (TCMPs) to ensure access, and attachment to adult healthcare providers, and 2) to identify strategies for providing support during the transition period, including through the development of physician and patient (or caregiver) navigated web-based tools, resources and recommendations for health system improvements. Methods: Physicians and nurses with expertise in areas including adult and pediatric epilepsy, family medicine, psychiatry, and varied allied health professionals were engaged to generate epilepsy-related TCMPs. Results: Through an iterative process spanning the course of over a year, TCMPs were developed to cover areas including: treatment responsive and resistant epilepsy, ketogenic diet, epilepsy surgery, women’s issues, mental health, and psychosocial aspects of epilepsy. The TCMPs referenced established guidelines and best practices in the literature wherever possible. Caregiver roles and responsibilities were outlined, remaining cognoscent of available provincial resources. Conclusions: Epilepsy specific TCMPs can be developed through a collaborative approach between pediatric and adult healthcare providers, easing the patient experience, creating educated accountability, and providing a forum to identify and address gaps of care in adolescents with epilepsy.
This paper describes the system architecture of a newly constructed radio telescope – the Boolardy engineering test array, which is a prototype of the Australian square kilometre array pathfinder telescope. Phased array feed technology is used to form multiple simultaneous beams per antenna, providing astronomers with unprecedented survey speed. The test array described here is a six-antenna interferometer, fitted with prototype signal processing hardware capable of forming at least nine dual-polarisation beams simultaneously, allowing several square degrees to be imaged in a single pointed observation. The main purpose of the test array is to develop beamforming and wide-field calibration methods for use with the full telescope, but it will also be capable of limited early science demonstrations.
Spectacular celestine geodes occur in a Jurassic peri-evaporitic sequence (Ardon Formation) exposed in Makhtesh Ramon, southern Israel. The geodes are found only in one specific location: adjacent to an intrusive contact with a Lower Cretaceous basaltic dyke. Celestine, well known in sedimentary associations worldwide and considered as a low temperature mineral, may therefore be associated with magmatic-induced hydrothermal activity. Abundant fluid inclusions in celestine provide valuable information on its origin: gas-rich inclusions in celestine interiors homogenized at T≥200°C whereas smaller liquid-rich inclusions record the growth of celestine rims at T≤200°C. Near 0°C melting temperatures of some fluid inclusions and the occurrence of hydrous Ca-sulphate solid crystals in other inclusions indicate that celestine precipitated from variably concentrated Ca-sulphate aqueous solutions of meteoric origin. Celestine crystallized from meteoric water heated by the cooling basaltic dyke at shallow levels (c. 160 m) during a Lower Cretaceous thermal perturbation recorded by regional uplift and magmatism. The 87Sr/86Sr ratio of geode celestine, 0.7074, is similar to that measured in the dolostones of the host Jurassic sequence, but differs markedly from the non-radiogenic ratio of the dyke. Strontium in celestine was derived from dolostones preserving the 87Sr/86Sr of Lower Jurassic seawater, while sulphur (δ34S = 19.9‰) was provided by in situ dissolution of precursor marine gypsum (δ34S = 16.8‰) indicated by relict anhydrite inclusions in celestine. Low-temperature meteoric fluid flow during the Campanian caused alteration of the dyke into secondary clays and alteration of geodal celestine into quartz, calcite and iron oxides.
The PULSE@Parkes project has been designed to monitor the rotation of radio pulsars over time spans of days to years. The observations are obtained using the Parkes 64-m and 12-m radio telescopes by Australian and international high school students. These students learn the basis of radio astronomy and undertake small projects with their observations. The data are fully calibrated and obtained with the state-of-the-art pulsar hardware available at Parkes. The final data sets are archived and are currently being used to carry out studies of 1) pulsar glitches, 2) timing noise, 3) pulse profile stability over long time scales and 4) the extreme nulling phenomenon. The data are also included in other projects such as gamma-ray observatory support and for the Parkes Pulsar Timing Array project. In this paper we describe the current status of the project and present the first scientific results from the Parkes 12-m radio telescope. We emphasise that this project offers a straightforward means to enthuse high school students and the general public about radio astronomy while obtaining scientifically valuable data sets.
The existence of a stream of tidally stripped stars from the Sagittarius dwarf galaxy demonstrates that the Milky Way is still in the process of accreting mass. More recently, an extensive stream of stars has been uncovered in the halo of the Andromeda galaxy (M31), revealing that it too is cannibalising a small companion. This paper reports the recent observations of this stream, determining its spatial and kinematic properties, and tracing its three-dimensional structure, as well as describing future observations and what we may learn about the Andromeda galaxy from this giant tidal stream.
The Parkes pulsar data archive currently provides access to 144044 data files obtained from observations carried out at the Parkes observatory since the year 1991. Around 105 files are from surveys of the sky, the remainder are observations of 775 individual pulsars and their corresponding calibration signals. Survey observations are included from the Parkes 70 cm and the Swinburne Intermediate Latitude surveys. Individual pulsar observations are included from young pulsar timing projects, the Parkes Pulsar Timing Array and from the PULSE@Parkes outreach program. The data files and access methods are compatible with Virtual Observatory protocols. This paper describes the data currently stored in the archive and presents ways in which these data can be searched and downloaded.