A kilonova as the electromagnetic counterpart to a gravitational-wave source.

Gravitational waves were discovered with the detection of binary black-hole mergers and they should also be detectable from lower-mass neutron-star mergers. These are predicted to eject material rich in heavy radioactive isotopes that can power an electromagnetic signal. This signal is luminous at optical and infrared wavelengths and is called a kilonova. The gravitational-wave source GW170817 arose from a binary neutron-star merger in the nearby Universe with a relatively well confined sky position and distance estimate. Here we report observations and physical modelling of a rapidly fading electromagnetic transient in the galaxy NGC 4993, which is spatially coincident with GW170817 and with a weak, short γ-ray burst. The transient has physical parameters that broadly match the theoretical predictions of blue kilonovae from neutron-star mergers. The emitted electromagnetic radiation can be explained with an ejected mass of 0.04 ± 0.01 solar masses, with an opacity of less than 0.5 square centimetres per gram, at a velocity of 0.2 ± 0.1 times light speed. The power source is constrained to have a power-law slope of -1.2 ± 0.3, consistent with radioactive powering from r-process nuclides. (The r-process is a series of neutron capture reactions that synthesise many of the elements heavier than iron.) We identify line features in the spectra that are consistent with light r-process elements (atomic masses of 90-140). As it fades, the transient rapidly becomes red, and a higher-opacity, lanthanide-rich ejecta component may contribute to the emission. This indicates that neutron-star mergers produce gravitational waves and radioactively powered kilonovae, and are a nucleosynthetic source of the r-process elements.

Slowly fading super-luminous supernovae that are not pair-instability explosions.

Super-luminous supernovae that radiate more than 10(44) ergs per second at their peak luminosity have recently been discovered in faint galaxies at redshifts of 0.1-4. Some evolve slowly, resembling models of 'pair-instability' supernovae. Such models involve stars with original masses 140-260 times that of the Sun that now have carbon-oxygen cores of 65-130 solar masses. In these stars, the photons that prevent gravitational collapse are converted to electron-positron pairs, causing rapid contraction and thermonuclear explosions. Many solar masses of (56)Ni are synthesized; this isotope decays to (56)Fe via (56)Co, powering bright light curves. Such massive progenitors are expected to have formed from metal-poor gas in the early Universe. Recently, supernova 2007bi in a galaxy at redshift 0.127 (about 12 billion years after the Big Bang) with a metallicity one-third that of the Sun was observed to look like a fading pair-instability supernova. Here we report observations of two slow-to-fade super-luminous supernovae that show relatively fast rise times and blue colours, which are incompatible with pair-instability models. Their late-time light-curve and spectral similarities to supernova 2007bi call the nature of that event into question. Our early spectra closely resemble typical fast-declining super-luminous supernovae, which are not powered by radioactivity. Modelling our observations with 10-16 solar masses of magnetar-energized ejecta demonstrates the possibility of a common explosion mechanism. The lack of unambiguous nearby pair-instability events suggests that their local rate of occurrence is less than 6 × 10(-6) times that of the core-collapse rate.

Newly formed dust within the circumstellar environment of SN Ia-CSM 2018evt.

Dust associated with various stellar sources in galaxies at all cosmic epochs remains a controversial topic, particularly whether supernovae play an important role in dust production. We report evidence of dust formation in the cold, dense shell behind the ejecta-circumstellar medium (CSM) interaction in the Type Ia-CSM supernova (SN) 2018evt three years after the explosion, characterized by a rise in mid-infrared emission accompanied by an accelerated decline in the optical radiation of the SN. Such a dust-formation picture is also corroborated by the concurrent evolution of the profiles of the Hα emission line. Our model suggests enhanced CSM dust concentration at increasing distances from the SN as compared to what can be expected from the density profile of the mass loss from a steady stellar wind. By the time of the last mid-infrared observations at day +1,041, a total amount of 1.2 ± 0.2 × 10-2 M⊙ of new dust has been formed by SN 2018evt, making SN 2018evt one of the most prolific dust factories among supernovae with evidence of dust formation. The unprecedented witness of the intense production procedure of dust may shed light on the perceptions of dust formation in cosmic history.

Transit Use and Health Care Costs: A Cross-sectional Analysis.

INTRODUCTION: Greater transit use is associated with higher levels of physical activity, which is associated with lower health risks and better health outcomes. However, there is scant evidence about whether health care costs differ based on level of transit ridership. METHODS: A sample (n=947) of members of Kaiser Permanente in the Portland, Oregon area were surveyed in 2015 about their typical use of various modes of travel including transit. Electronic medical record-derived health care costs were obtained among these members for the prior three years. Analysis examined proportional costs between High transit users (3+ days/week), Low transit users (1-2 days/week), and Non-users adjusting for age and sex, and then individually (base models) and together for demographic and health status variables. RESULTS: In separate base models across individual covariates, High transit users had lower total health care costs (59-69% of Non-user's costs) and medication costs (31-37% of Non-users' costs) than Non-users. Low transit users also had lower total health care (69%-76% of Non-users' costs) and medication costs (43-57% transit of Non-user's costs) than Non-users. High transit users' outpatient costs were also lower (77-82% of Non-users). In fully-adjusted models, total health care and medication costs were lower among High transit users' (67% and 39%) and Low transit users' (75% and 48%) compared to Non-users, but outpatient costs did not differ by transit use. CONCLUSIONS: Findings have implications for the potential cost benefit of encouraging and supporting more transit use, although controlled longitudinal and experimental evidence is needed to confirm findings and understand mechanisms.

A behavioral weight-loss intervention for persons with serious mental illness in psychiatric rehabilitation centers.

OBJECTIVE: Overweight and obesity are epidemic in populations with serious mental illnesses. We developed and pilot-tested a behavioral weight-loss intervention appropriately tailored for persons with serious mental disorders. METHODS: We conducted a single-arm pilot study in two psychiatric rehabilitation day programs in Maryland, and enrolled 63 overweight or obese adults. The 6-month intervention provided group and individual weight management and group physical activity classes. The primary outcome was weight change from baseline to 6 months. RESULTS: A total of 64% of those potentially eligible enrolled at the centers. The mean age was 43.7 years; 56% were women; 49% were white; and over half had schizophrenia or a schizoaffective disorder. One-third had hypertension and one-fifth had diabetes. In total, 52 (82%) completed the study; others were discharged from psychiatric centers before completion of the study. Average attendance across all weight management sessions was 70% (87% on days participants attended the center) and 59% for physical activity classes (74% on days participants attended the center). From a baseline mean of 210.9 lbs (s.d. 43.9), average weight loss for 52 participants was 4.5 lb (s.d. 12.8) (P<0.014). On average, participants lost 1.9% of body weight. Mean waist circumference change was 3.1 cm (s.d. 5.6). Participants on average increased the distance on the 6-minute walk test by 8%. CONCLUSION: This pilot study documents the feasibility and preliminary efficacy of a behavioral weight-loss intervention in adults with serious mental illness who were attendees at psychiatric rehabilitation centers. The results may have implications for developing weight-loss interventions in other institutional settings such as schools or nursing homes.

Efficacy of a single application of a 12.5% pyriprole topical solution against laboratory infestations with ticks (Ixodes ricinus, Dermacentor reticulatus, and Rhipicephalus sanguineus) on dogs.

In three separate studies, the efficacy of a single treatment with a 12.5% pyriprole spot-on solution was investigated against induced infestation with Ixodes ricinus, Dermacentor reticulatus and Rhipicephalus sanguineus on dogs (both sexes; Beagles in Studies 1 and 2, mixed-breed in Study 3). For each tick species, one group of 8 dogs left untreated (Studies 1 and 2) or treated with a placebo solution (Study 3) was compared with another group treated once with the spot-on solution at a dose rate of at least 12.5mg/kg. The dogs were infested with 50 unfed adult ticks of the respective species at various time-points before and after treatment and the surviving attached and unattached ticks were recorded 48 h after re-infestation. For each tick species, efficacy was assessed for each time-point and cumulatively for the whole evaluation period. The dogs were submitted to general health observations and clinical assessments during the study. Efficacy against I. ricinus and R. sanguineus was 100% during the whole evaluation period of 30 days. For D. reticulatus cumulative efficacy for the 30 days after treatment was 98.9%. The product was well tolerated by all the animals.

The effect of water and shampooing on the efficacy of a pyriprole 12.5% topical solution against brown dog tick (Rhipicephalus sanguineus) and cat flea (Ctenocephalides felis) infestations on dogs.

The efficacy of a single treatment with a 12.5% pyriprole spot-on formulation against induced infestations with R. sanguineus ticks and cat fleas (C. felis) as well as its persistence after repeated washing and shampooing was investigated in four separate studies. In a first study on R. sanguineus involving 32 beagle dogs, the efficacy at various time-points during the 30 days that followed treatment assessed 48 h after re-infestation ranged from 100% to 99.3%. No engorged ticks, alive or dead, were found in the treated animals. Shampooing 2 days after treatment and weekly washings did not affect the efficacy. In a second study on R. sanguineus involving 32 beagle dogs, the efficacy at various time-points during the 30 days that followed treatment assessed 48 h after re-infestation ranged from 100% to 96.8%. Single washing 8h after treatment and single shampooing 24 h after treatment had no negative impact on the efficacy of the product. In a third study on C. felis involving 28 beagle dogs, the efficacy at various time-points during the 30 days that followed treatment assessed 48 h after re-infestation was always 100% and weekly washings did not diminish the efficacy. In a last study on C. felis involving 24 beagle dogs, the efficacy at various time-points during the 5 weeks that followed treatment assessed 48 h after re-infestation ranged from 100% to 99.8%, and shampooing 24 h after treatment did not reduce the efficacy. The product was well tolerated by the dogs.

Efficacy of a novel formulation of metaflumizone for the control of fleas (Ctenocephalides felis) on cats.

A novel spot-on formulation containing metaflumizone (ProMeris for Cats, Fort Dodge Animal Health, Overland Park, KS) was evaluated in five laboratory studies to determine the duration of residual efficacy in cats against fleas after a single spot treatment. In each study, eight domestic shorthair cats were randomly allocated to each treatment group and individually housed. One group in each study remained non-treated. In one study, an additional group of eight cats was treated with a placebo formulation. Cats were treated topically with metaflumizone formulation to provide a dose of at least 40mg metaflumizone/kg. Cats were infested with 100 cat fleas (Ctenocephalides felis felis) once per week for approximately 8 weeks. Cats were comb counted 48h after treatment and each infestation to determine the number of viable fleas present. There were no significant differences in flea counts between the non-treated control and the placebo-treated control (P>0.05) other than a 26% reduction at week 1, demonstrating that the formulation excipients had no activity. Metaflumizone treatment resulted in significantly lower flea numbers relative to non-treated controls on all post-treatment count days (P<0.05). Metaflumizone provided >90% control of flea infestations up to 7 weeks following a single treatment.

Sociodemographic associations of 4-year overweight and obese incidence among a racially diverse cohort of healthy weight 18-year-olds.

BACKGROUND: Emerging adulthood is a critical time for excess weight gain. Risk can be masked if recommended overweight and obesity cut-points for Asians are not employed. OBJECTIVES: To determine the associations among sociodemographic factors and occurrence of overweight and obesity among normal weight 18-year olds. METHODS: Normal weight (body mass index < 25 kg m-2 ; <23 kg m-2 for Asians) 18-year-old (9037 boys, 13 786 girls, 36% Hispanic, 34% non-Hispanic Whites, 10% Black, 5% Asian) members of a healthcare organization in 2008 were followed through 2012 to identify incidence of overweight and obesity. Hazard ratios (HR) and 95% confidence intervals (CI) were determined controlling for sex, race/ethnicity, neighbourhood education, neighbourhood income and smoking status. RESULTS: After 3 years of follow-up, the HR for overweight was 1.28 (95% CI: 1.12, 1.45) in the lowest quartile of neighbourhood education compared with the highest. Asians and Pacific Islanders had greater risk of overweight (HR 2.89, 95% CI: 2.55, 3.28; HR 3.13, 95% CI 2.23, 4.38) than non-Hispanic Whites. Girls and Blacks were more likely to become obese than boys and non-Hispanic Whites, as were those living in the lowest neighbourhood education quartile and lower neighbourhood income quartiles. CONCLUSIONS: Girls, Asians, Blacks and those living in low education and income neighbourhoods during adolescence are at risk for excessive weight gain trajectories.

Prevalence of hypercholesterolemia among siblings of persons with premature coronary heart disease. Application of the Second Adult Treatment Panel guidelines.

BACKGROUND: Increased blood cholesterol, specifically high low-density lipoprotein cholesterol, increases risk for coronary heart disease (CHD). Persons with a positive family history of premature CHD also are at markedly increased risk. OBJECTIVE: To examine the prevalence of hypercholesterolemia based on the second report of the National Cholesterol Educational Program Adult Treatment Panel (ATP II) guidelines in the asymptomatic healthy siblings of people with premature CHD. METHODS: A total of 668 asymptomatic healthy siblings (354 men and 314 women) underwent screening for risk factors for CHD. Siblings were categorized into treatment categories for primary prevention defined by ATP II. The percentage who were candidates for intervention were compared with the published national estimates for those without CHD from the third National Health and Nutrition Examination Survey (NHANES III). RESULTS: Based on ATP II guidelines, 65% of the asymptomatic adult siblings required fasting lipoprotein analysis compared with 33% of adults without CHD in the national reference population. Of the siblings who met the criteria for fasting lipoprotein analysis, most (56%) were candidates for dietary therapy, more than twice the proportion of adults from NHANES III. The percentage of the siblings who qualified for drug intervention and dietary therapy was 3 times greater than the national sample, 33% vs 11%, respectively. Assuming a 10% hypothetical reduction in low-density lipoprotein cholesterol levels as the result of dietary modification, the proportion of the sibling sample who were possible candidates for drug therapy was 20%, still 4 times that predicted for the national sample. CONCLUSIONS: These results underscore the need for aggressive detection and treatment of hypercholesterolemia in this easily identifiable high-risk population of siblings of people with premature CHD.

Evaluation of the efficacy of emodepside plus praziquantel topical solution against ascarid infections (Toxocara cati or Toxascaris leonina) in cats.

Eleven controlled studies were conducted in the United States and Europe to evaluate the efficacy of a topical solution of emodepside (3 mg/kg)+praziquantel (12 mg/kg) (Profender, Bayer AG, Leverkusen, Germany) against infection with various stages of the ascarid nematodes Toxocara cati and Toxascaris leonina. Infections were induced by administration of larvated ascarid eggs, and stage-specific efficacy was evaluated by treating cats at scheduled intervals post-inoculation. All studies featured random allocation to treatment groups, placebo-treated control animals and assessment of outcome measures by masked personnel. The product (emodepside+praziquantel topical solution) was 100% effective against mature adults and immature adult T. cati. In addition, it was 96.8% effective against third stage larvae and at least 99.4% effective against fourth stage larvae of T. cati, respectively. Efficacy against mature, immature adult and L4 stages of T. leonina exceeded 93.4%, but regulatory "adequacy of infection" criteria were not met in some studies. No adverse reactions to treatment were noted in cats treated with the emodepside+praziquantel topical solution.

Efficacy of a topically administered combination of emodepside and praziquantel against mature and immature Ancylostoma tubaeforme in domestic cats.

This paper reports the efficacy of emodepside/praziquantel spot-on (Profender), Bayer AG, Leverkusen, Germany), a novel broad-spectrum anthelmintic for dermal application, against L4 larvae and immature adult and adult stages of Ancylostoma tubaeforme in cats. The formulation contains 2.14% (w/w) emodepside and 8.58% (w/v) praziquantel, with emodepside being active against gastrointestinal nematodes and praziquantel against cestodes. Five randomized, blinded and controlled laboratory studies demonstrated 100% efficacy of emodepside/praziquantel spot-on against mature A. tubaeforme and an efficacy of >95% and >97%, respectively, against L4 larvae and immature adults (based on worm counts after necropsy) at approximately the minimum proposed dose rate in cats of 3.0 mg emodepside and 12.0 mg praziquantel/kg body weight. No adverse reactions to the treatment were observed. It is concluded that emodepside/praziquantel spot-on is an effective and safe treatment against infections with mature and immature A. tubaeforme. Emodepside/praziquantel spot-on will considerably facilitate the treatment of cats against nematodes and cestodes compared with orally administered preparations.

Antibodies with specificities to preselected protein regions evoked by free synthetic peptides representing protein antigenic sites or other surface locations: demonstration with myoglobin.

Previous studies have resulted in the determination of the entire structure of myoglobin. The present work was carried out to investigate the antigenicity of the synthetic antigenic sites and other surface peptides of Mb in their free form (i.e. without coupling to a carrier). Site 1 (peptide 15-22), site 2 (peptide 56-62), site 3 (peptide 94-100), site 4 (peptide 113-120), site 5 (peptide 145-151) and two surface peptides, peptide 1-6 and peptide 121-127, were injected in complete Freund's adjuvant into Balb/c mice. Radioimmune antibody binding studies showed that immunization with each of these peptides, in their free form, resulted in the formation of antibodies that bound specifically to Mb and to the immunizing peptide. The advantage and significance of these findings are discussed.

Psychosocial predictors of weight loss by race and sex.

This paper examined the psychosocial predictors of weight loss among race and sex subgroups. Analyses included overweight and obese participants from the PREMIER study, a previously published randomized trial that examined the effects of two multi-component lifestyle interventions on blood pressure among pre-hypertensive and stage 1 hypertensive adults. Both intervention conditions received behavioural recommendations for weight loss and group sessions. Weight and psychosocial measures of self-efficacy and social support for diet and exercise were assessed at baseline and at 6 months. There were 157 African-American (AA) women, 46 AA men, 203 non-AA women and 182 non-AA men with an average age of 50 years and average body mass index of 34 at baseline. Multiple predictor regression models were performed individually by race and sex subgroup. Among AA women, increases in diet self-efficacy were associated with weight loss. Among AA men, increases in diet-related social support and self-efficacy, along with increases in family support to exercise, were associated with weight loss (all Ps <0.05). Among non-AA women, increases in friends' support to exercise and exercise-related self-efficacy were associated with weight loss, and among non-AA men only increases in diet self-efficacy were associated with weight loss (all Ps <0.05). These results emphasize the need for targeted interventions based on race and sex to optimize the impact of lifestyle-based weight loss programmes.

The short-term effects of cisplatin chemotherapy on bone turnover.

Cisplatin is an effective agent in the treatment of osteosarcoma of bone but little is known of its effects on normal bone turnover. Twenty-four dogs divided into three study groups were used to study the effect of cisplatin on normal bone turnover at the distant site of surgery. Group 1 served as the control group, group 2 received four cycles of cisplatin every 3 weeks before the surgery, and group 3 received four cycles postoperatively. The bone turnover rate was evaluated by measuring levels of systemic bone markers, osteocalcin, alkaline phospohatase, urine pyridinoline cross-links, and by determination histomorphometric indices. Histomorphological analysis showed poor correlation on bone formation with systemic bone markers at distant sites of surgery. Histomorphometrically normal bone turnover was affected by administration of cisplatin, but the effect was temporary, late, and less significant than what occurred at the surgical site. Our data showed that significant effects of cisplatin are observed at the site of active cellular induction and proliferation, such as implant-host interface, and less effects are seen at the sites of normal bone turnover.

Role of sodium in modulation of myocardial hypertrophy in renal hypertensive rats.

To evaluate the role of dietary sodium and antihypertensive drugs in the modulation of myocardial structure, especially myosin isozymic pattern, renal hypertensive rats (two-kidney, one clip) were treated with a sodium-deficient diet (7 mEq/kg), captopril, or atenolol. Native myosin was extracted under nondissociating conditions and separated by polyacrylamide gel electrophoresis. The percentage of myosin isozyme V1 was significantly decreased from 71.5 +/- 7.5 (Wistar controls) to 52.4 +/- 1.7% (p less than 0.05) in renal hypertensive rats and was associated with an increase in V3 component from 12.7 +/- 5.1 (Wistar controls) to 23.1 +/- 1.4% (renal hypertensive rats; p less than 0.05). There was a dramatic change in the myosin isozyme distribution pattern after treatment with low sodium and captopril. Six weeks of low sodium therapy in renal hypertensive rats resulted in an increase in V1 from 52.4 +/- 1.7 to 74.8 +/- 4.8% and a reduction in V3 from 23.1 +/- 1.4 to 9.5 +/- 2.4%. Normal rats treated with low sodium showed similar results. The percentage distribution of isozymes after low sodium therapy in the captopril-treated rats was not different from that in normal Wistar controls. Captopril therapy also caused an increase in V1 and a decrease in V3. Atenolol therapy, on the other hand, caused a significant increase in V3 and decrease in V1 with no change in blood pressure or heart weight. These data suggest that dietary sodium may play an important role in the modulation of myocardial mass and may modulate signals for synthesis of V1 or V3 myosin phenotypes.

Cross-linking and new bone collagen synthesis in immobilized and recovering primate osteoporosis.

Quantification of collagen cross-links of monkey bone (tibia), from various time periods of immobilization (up to 7 months) and their subsequent reambulation (up to 40 months) was determined. Results indicated reducible cross-link concentrations markedly increased and peaked at the seven-month period of immobilization and returned to control values after 40 months of recovery. Chromatographic profiles of the major cross-linked peptides indicated that the increased cross-linking after seven months immobilization occurred between residue Hylald-16c as well as Lysald-16c of the alpha 1 chains and residue 87 Hyl of alpha chains of type I collagen. Mature, stable cross-link concentrations as well as their molecular loci remained constant throughout immobilization and reambulation. These results strongly suggest that rapid new bone collagen synthesis occurred during the osteoporotic state due to immobilization. With long-term recovery, the rate of collagen synthesis apparently returned to match the control bone.

Immobilization-associated osteoporosis in primates.

The progressive osteopenic changes in tibial compact bone in adult male monkeys (Macaca nemestrina) were examined histologically during chronic studies of immobilization. The animals were restrained in a semirecumbent position, which reduces normally occurring stresses in the lower extremities and results in bone mass loss. The longest immobilization studies were of 7 months duration. Losses of haversian bone tended to occur predominantly in the proximal tibia and were characterized by increased activation with excessive depth of penetration of osteoclastic activity. There was no apparent regulation of the size and orientation of resorption cavities. Rapid bone loss seen during 10 weeks of immobilization appeared to be due to unrestrained osteoclastic activity without controls and regulation, which are characteristic of adaptive systems. The general pattern of loss persisted throughout 7 months of immobilization. Clear-cut evidence of a formation phase in haversian bone was seen only after 2 months of reambulation. During this period osteoblasts accumulated within resorption cavities, and there was matrix apposition. Within 6 months of recovery there was increased bone turnover, and resorption cavities with diameters of 500-1500 micron were filled partially with new bone; the mean wall thickness of new bone was 2 to 3 times larger than normal. In addition there were numerous remodeling sites that were of normal size and orientation. Trabecular bone was lost during immobilization, and it is probable that losses of large trabecular plates are not replaced, and consequently original bone volume in the cross section is not recovered. In this immobilization model we observed bone resorption occurring for long periods without apparent interruption.(ABSTRACT TRUNCATED AT 250 WORDS)