A nearby transiting rocky exoplanet that is suitable for atmospheric investigation.

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

Likely Transiting Exocomets Detected By Kepler.

We present the first good evidence for exocomet transits of a host star in continuum light in data from the Kepler mission. The Kepler star in question, KIC 3542116, is of spectral type F2V and is quite bright at Kp = 10. The transits have a distinct asymmetric shape with a steeper ingress and slower egress that can be ascribed to objects with a trailing dust tail passing over the stellar disk. There are three deeper transits with depths of ≃ 0.1% that last for about a day, and three that are several times more shallow and of shorter duration. The transits were found via an exhaustive visual search of the entire Kepler photometric data set, which we describe in some detail. We review the methods we use to validate the Kepler data showing the comet transits, and rule out instrumental artefacts as sources of the signals. We fit the transits with a simple dust-tail model, and find that a transverse comet speed of ∼35-50 km s-1 and a minimum amount of dust present in the tail of ∼ 1016 g are required to explain the larger transits. For a dust replenishment time of ∼10 days, and a comet lifetime of only ∼300 days, this implies a total cometary mass of ≳ 3 × 1017 g, or about the mass of Halley's comet. We also discuss the number of comets and orbital geometry that would be necessary to explain the six transits detected over the four years of Kepler prime-field observations. Finally, we also report the discovery of a single comet-shaped transit in KIC 11084727 with very similar transit and host-star properties.

Kepler's optical phase curve of the exoplanet HAT-P-7b.

Ten days of photometric data were obtained during the commissioning phase of the Kepler mission, including data for the previously known giant transiting exoplanet HAT-P-7b. The data for HAT-P-7b show a smooth rise and fall of light from the planet as it orbits its star, punctuated by a drop of 130 +/- 11 parts per million in flux when the planet passes behind its star. We interpret this as the phase variation of the dayside thermal emission plus reflected light from the planet as it orbits its star and is occulted. The depth of the occultation is similar in photometric precision to the detection of a transiting Earth-size planet for which the mission was designed.

Homes for extraterrestrial life: extrasolar planets.

Astronomers are now discovering giant planets orbiting other stars like the sun by the dozens. But none of these appears to be a small rocky planet like the earth, and thus these planets are unlikely to be capable of supporting life as we know it. The recent discovery of a system of three planets is especially significant because it supports the speculation that planetary systems, as opposed to single orbiting planets, may be common. Our ability to detect extrasolar planets will continue to improve, and space missions now in development should be able to detect earth-like planets.

How the district nurse cares for the terminally ill patient with cachexia.

The aims of this study were to establish how district nurses cared for terminally ill patients with cachexia at home; to establish the priorities in the care given; and to establish the nurses' understanding of the core activities undertaken. The study allowed the views of district nurses to be examined in the context of their understanding of the care they gave. A literature review revealed that the metabolic disorders associated with cachexia mean that the condition is not simply the result of insufficient food intake. However, data from the study suggest that some district nurses have little understanding of the metabolic disorders associated with cachexia and revealed that care centres around advising and encouraging the cachectic patient to increase his/her food intake; such advice and encouragement were seen as the core activities in caring for the cachectic patient at home. This small study of 10 district nurse suggests that cachectic patients are put under unnecessary pressure to eat by both the formal and informal carer, and that as a result the patient may feel unsupported by the carers' lack of knowledge about his/her condition.

Resolution of ephedrine in supercritical CO(2): A novel technique for the separation of chiral drugs.

Racemic ephedrine has been resolved by diastereomeric salt formation with mandelic acid using supercritical CO(2) as precipitating agent. Crystallizations were performed using the Solution Enhanced Dispersion by Supercritical Fluids (SEDS) technique. Temperature was varied between 35 and 75 degrees C, and pressures ranged from 100 to 350 bar. Resolution, determined by chiral capillary electrophoresis, is described as a function of temperature and density of the supercritical fluid. A comparison of SEDS-produced material with a conventional resolution method shows that SEDS-crystallized material exhibits identical properties to conventionally crystallized material.

Self-injurious behaviour in police custody.

A Royal Commission into Aboriginal Deaths in Custody in Australia, reported in April 1991, focused attention on the problem of self-injurious behaviour among incarcerated individuals. This paper examines the specific issue of the police custodial setting. A review of the relevant literature has been undertaken to identify risk factors and determine profiles of persons at risk. Preventive approaches are examined and formats for screening questionnaires are advanced.

SETI target selection.

The NASA High Resolution Microwave Survey consists of two complementary elements: a Sky Survey of the entire sky to a moderate level of sensitivity; and a Targeted Search of nearby stars, one at a time, to a much deeper level of sensitivity. In this paper we propose strategies for target selection. We have two goals: to improve the chances of successful detection of signals from technical civilizations that inhabit planets around solar-type stars, and to minimize the chances of missing signals from unexpected sites. For the main Targeted Search survey of approximately 1000 nearby solar-type stars, we argue that the selection criteria should be heavily biased by what we know about the origin and evolution of life here on Earth. We propose that observations of stars with stellar companions orbiting near the habitable zone should be de-emphasized, because such companions would prevent the formation of habitable planets. We also propose that observations of stars younger than about three billion years should be de-emphasized in favor of older stars, because our own technical civilization took longer than three billion years to evolve here on Earth. To provide the information needed for the preparation of specific target lists, we have undertaken an inventory of a large sample of solar-type stars out to a distance of 60 pc, with the goal of characterizing the relevant astrophysical properties of these stars, especially their ages and companionship. To complement the main survey, we propose that a modest sample of the nearest stars should be observed without any selection biases whatsoever. Finally, we argue that efforts to identify stars with planetary systems should be expanded. If found, such systems should receive intensive scrutiny.

Cell-specific posttranslational processing of the surfactant-associated protein SP-B.

Pulmonary surfactant-associated protein B (SP-B) is a 9-kDa lung-specific protein expressed in alveolar epithelial type II cells and Clara cells. The protein markedly increases the surface activity of phospholipids and is an active component in some surfactants in clinical use. SP-B is produced from a 43-kDa precursor protein by proteolytic cleavage of flanking regions from both the NH2- and COOH-terminal ends of the active protein. In this study we have compared the nature of the posttranslational processing of the SP-B precursor in type II cells and in a heterologous cell line transfected with the SP-B precursor. We found that isolated type II cells produce the 9-kDa form of SP-B from the precursor through a series of intermediates detectable in the cell lysates. In contrast Chinese hamster ovary cells stably transfected with the full-length human SP-B precursor produce the precursor and a 26-kDa intermediate but not the 9-kDa protein. The precursor protein in both cell types is glycosylated with NH2-linked sugars. Our results suggest there is cell specificity in the posttranslational processing of the SP-B precursor.

Case management of the anemic patient. Epoetin alfa: focus on dialysis efficiency.

Dialysis efficiency has traditionally been measured using kinetic modeling (KT/Vurea). However, once anemia is corrected with Epoetin alfa, using urea as the only measure of dialysis effectiveness may not be adequate. Two case studies describe the use of the urea kinetic model and other means of assessing dialysis efficiency in nonanemic patients.

Nephrology nursing care plan and patient education plan for the patient receiving Epogen.

This article presents a nursing care plan and patient education plan for patients receiving recombinant human erythropoietin in the form of Epogen (Epoetin alfa). Eight nursing diagnoses and a standard and outcomes for patient education are included.

Epoetin alfa: patient management issues and development through recombinant DNA technology. Part 1: Focus on Epoetin alfa patient management and recombinant DNA technology.

The emergence of the Epoetin alfa as an effective therapy in the treatment of the anemia of chronic renal failure has reemphasized the importance of nursing monitoring and intervention in the treatment of these patients. This article examines the role of nurses in monitoring and managing patients receiving Epoetin alfa and the development of medications, such as Epoetin alfa, with recombinant DNA technology.

Ignition of global wildfires at the Cretaceous/Tertiary boundary.

An impressive amount of evidence supports the proposal of Alvarez et al. that the Cretaceous era was ended abruptly by the impact of a comet or asteroid. The recent discovery of an apparently global soot layer at the Cretaceous/Tertiary boundary indicates that global wildfires were somehow ignited by the impact. Here we show that the thermal radiation produced by the ballistic re-entry of ejecta condensed from the vapour plume of the impact could have increased the global radiation flux by factors of 50 to 150 times the solar input for periods ranging from one to several hours. This great increase in thermal radiation may have been responsible for the ignition of global wildfires, as well as having deleterious effects on unprotected animal life.

Practical considerations of recombinant human erythropoietin therapy.

The effect of long-term hemodialysis in 58 nonanemic end-stage renal disease patients treated with recombinant human erythropoietin (r-HuEPO; EPOGEN [epoetin alfa], AMGEN Inc, Thousand Oaks, CA) has been examined in detail. Increased dialyzer prescription (Kt/V) was correlated with the need for a lower maintenance dose of r-HuEPO. After 1 year of therapy, stable increases in hemoglobin, hematocrit, and reticulocyte levels were obtained without other clinically significant hematologic changes. In a randomly selected subgroup of 14 patients, 5 developed predialysis increased diastolic pressures. In this group, an early increase in cardiac output and ejection fraction was accompanied by a decrease in total peripheral resistance index (TPRI). Later changes showed a steady increase in TPRI with an associated mild increase in mean arterial pressure. A slight increase in cardiac responsiveness to fistula occlusive maneuvers was also found. Hospital admissions and mortality rates were not significantly different from those of a cohort control population. At a fixed Kt/V there were slight decreases in solute clearances with correction of anemia, with phosphate, urate, and creatinine changing significantly. Corrective measures required simple compensatory adjustments in dialysis blood-flow rates. Intradialytic complications were noticeably improved. Patients receiving long-term r-HuEPO replacement therapy do remarkably well without major complications.

Renal transplantation: results in hemodialysis patients previously treated with recombinant human erythropoietin.

The eventual commonplace use of recombinant human erythropoietin (r-HuEPo) for the treatment of the anemia associated with chronic renal failure will have definite consequences in the dialysis supported patient. The effect of this nonanemic state on renal transplantation, both in the early posttransplant period as well as the waiting period, was examined in this study. Thirteen of 16 patients who were treated with the hormone and subsequently underwent cadaveric renal transplantation (Tx) were compared to control transplant patients from a typical chronic renal patient population. There seemed to be no difference in the length of hospital stay, need for dialysis support post-Tx, or severity of acute post-Tx renal failure as measured by the days of dialysis support given. Furthermore, there seemed to be no evidence of marrow unresponsiveness to endogenous erythropoietin produced by the functioning allograft, so that after an initial fall in hemoglobin and hematocrit, these parameters returned to normal levels at three to six months. HLA antibody production was also tracked over the course of chronic r-HuEPo therapy, and the response followed one of three patterns: (a) initially very high (100%) or very low (less than 15%) and showed no change; (b) moderate to high reactivity fell to lower levels with time; or (c) some stimulation noted without recent blood transfusions. Thus, patients entering end-stage renal failure without having been exposed to transfusions can be maintained in a low antibody state and perhaps increase the cadaveric kidneys available to them. Therefore, r-HuEPo therapy in patients who will subsequently undergo transplantation seems to have no deleterious effect on patient morbidity, or transplant outcome.(ABSTRACT TRUNCATED AT 250 WORDS)