Context.PG 1159-035, a pre-white dwarf with $T_{{\rm eff}}$$\simeq$ 140 000 K, is the prototype of both two classes: the PG 1159 spectroscopic class and the DOV pulsating class. Previous studies of ...PG 1159-035 photometric data obtained with the Whole Earth Telescope (WET) showed a rich frequency spectrum allowing the identification of 122 pulsation modes. Analyzing the periods of pulsation, it is possible to measure the stellar mass, the rotational period and the inclination of the rotation axis, to estimate an upper limit for the magnetic field, and even to obtain information about the inner stratification of the star. Aims.We have three principal aims: to increase the number of detected and identified pulsation modes in PG 1159-035, study trapping of the star's pulsation modes, and to improve or constrain the determination of stellar parameters. Methods.We used all available WET photometric data from 1983, 1985, 1989, 1993 and 2002 to identify the pulsation periods. Results.We identified 76 additional pulsation modes, increasing to 198 the number of known pulsation modes in PG 1159-035, the largest number of modes detected in any star besides the Sun. From the period spacing we estimated a mass $M/M_\odot$ = 0.59 ± 0.02 for PG 1159-035, with the uncertainty dominated by the models, not the observation. Deviations in the regular period spacing suggest that some of the pulsation modes are trapped, even though the star is a pre-white dwarf and the gravitational settling is ongoing. The position of the transition zone that causes the mode trapping was calculated at $r_{\rm c}/R_\star$ = 0.83 ± 0.05. From the multiplet splitting, we calculated the rotational period Prot = 1.3920 ± 0.0008 days and an upper limit for the magnetic field, $B < 2000$ G. The total power of the pulsation modes at the stellar surface changed less than 30% for $\ell$ = 1 modes and less than 50% for $\ell$ = 2 modes. We find no evidence of linear combinations between the 198 pulsation mode frequencies. PG 1159-035 models have not significative convection zones, supporting the hypothesis that nonlinearity arises in the convection zones in cooler pulsating white dwarf stars.
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Gene expression in a developmentally arrested, long-lived dauer population of Caenorhabditis elegans was compared with a nondauer (mixed-stage) population by using serial analysis of gene expression ...(SAGE). Dauer (152,314) and nondauer (148,324) SAGE tags identified 11,130 of the predicted 19,100 C. elegans genes. Genes implicated previously in longevity were expressed abundantly in the dauer library, and new genes potentially important in dauer biology were discovered. Two thousand six hundred eighteen genes were detected only in the nondauer population, whereas 2016 genes were detected only in the dauer, showing that dauer larvae show a surprisingly complex gene expression profile. Evidence for differentially expressed gene transcript isoforms was obtained for 162 genes. H1 histones were differentially expressed, raising the possibility of alternative chromatin packaging. The most abundant tag from dauer larvae (20-fold more abundant than in the nondauer profile) corresponds to a new, unpredicted gene we have named tts-1 (transcribed telomere-like sequence), which may interact with telomeres or telomere-associated proteins. Abundant antisense mitochondrial transcripts (2% of all tags), suggest the existence of an antisense-mediated regulatory mechanism in C. elegans mitochondria. In addition to providing a robust tool for gene expression studies, the SAGE approach already has provided the advantage of new gene/transcript discovery in a metazoan.
We have identified longevity-associated genes in a long-lived Caenorhabditis elegans daf-2 (insulin/IGF receptor) mutant using serial analysis of gene expression (SAGE), a method that efficiently ...quantifies large numbers of mRNA transcripts by sequencing short tags. Reduction of daf-2 signaling in these mutant worms leads to a doubling in mean lifespan. We prepared C. elegans SAGE libraries from 1, 6, and 10-d-old adult daf-2 and from 1 and 6-d-old control adults. Differences in gene expression between daf-2 libraries representing different ages and between daf-2 versus control libraries identified not only single genes, but whole gene families that were differentially regulated. These gene families are part of major metabolic pathways including lipid, protein, and energy metabolism, stress response, and cell structure. Similar expression patterns of closely related family members emphasize the importance of these genes in aging-related processes. Global analysis of metabolism-associated genes showed hypometabolic features in mid-life daf-2 mutants that diminish with advanced age. Comparison of our results to recent microarray studies highlights sets of overlapping genes that are highly conserved throughout evolution and thus represent strong candidate genes that control aging and longevity.
A retrospective analysis was conducted using state Medicaid prescription drug reimbursement claims for youths aged 5 through 14 years according to the race of the recipients of psychotropic and ...medical drugs.
A person-based data set was created from Medicaid administrative data for fiscal year 1991 from the state of Maryland to yield the following: (1) estimates of prevalence of prescription recipients per 100 eligible enrollees; (2) relative prescription use ratios according to race (African-American versus Caucasian); and (3) the interrelation of race and geographic region on prescription prevalence.
Five major findings were observed: (1) African-American youths with Medicaid insurance aged 5 through 14 were less than half (39% to 52%) as likely to have been prescribed psychotropic medications as Caucasian youths with Medicaid insurance; (2) the relative difference for nonpsychotropic medication classes was much less pronounced: African-American youths were prescribed nonpsychotropic medications at a rate 60% to 87% of the Caucasian youths' rate; (3) the stimulants (essentially methylphenidate) had the most disparate African-American/Caucasian ratio (1:2.5); (4) the racial disparity for psychotropics was not altered by partial (noncontinuous enrollment) eligibility status; and (5) although geographic variation reduced the racial disparity, the substantial racial difference (1:2.0) remained.
Compared with Caucasians, African-American youths aged 5 through 14 with Medicaid insurance coverage showed a distinctly lower rate of treatment with psychopharmacological agents.
Despite the overt nature of most motor and phonic tic phenomena, the development of valid and reliable scales to rate tic severity has been an elusive goal. The Yale Global Tic Severity Scale (YGTSS) ...is a new clinical rating instrument that was designed for use in studies of Tourette's syndrome and other tic disorders. The YGTSS provides an evaluation of the number, frequency, intensity, complexity, and interference of motor and phonic symptoms. Data from 105 subjects, aged 5 to 51 years, support the construct, convergent, and discriminant validity of the instrument. These results indicate that the YGTSS is a promising instrument for the assessment of tic severity in children, adolescents and adults.
Context.
Supernovae (SNe) Type Ibn are rapidly evolving and bright (
M
R, peak
∼ −19) transients interacting with He-rich circumstellar material (CSM). SN 2018bcc, detected by the ZTF shortly after ...explosion, provides the best constraints on the shape of the rising light curve (LC) of a fast Type Ibn.
Aims.
We used the high-quality data set of SN 2018bcc to study observational signatures of the class. Additionally, the powering mechanism of SN 2018bcc offers insights into the debated progenitor connection of Type Ibn SNe.
Methods.
We compared well-constrained LC properties obtained from empirical models with the literature. We fit the pseudo-bolometric LC with semi-analytical models powered by radioactive decay and CSM interaction. Finally, we modeled the line profiles and emissivity of the prominent He
I
lines, in order to study the formation of P-Cygni profiles and to estimate CSM properties.
Results.
SN 2018bcc had a rise time to peak of the LC of 5.6
−0.1
+0.2
days in the restframe with a rising shape power-law index close to 2, and seems to be a typical rapidly evolving Type Ibn SN. The spectrum lacked signatures of SN-like ejecta and was dominated by over 15 He emission features at 20 days past peak, alongside Ca and Mg, all with
V
FWHM
∼ 2000 km s
−1
. The luminous and rapidly evolving LC could be powered by CSM interaction but not by the decay of radioactive
56
Ni. Modeling of the He
I
lines indicated a dense and optically thick CSM that can explain the P-Cygni profiles.
Conclusions.
Like other rapidly evolving Type Ibn SNe, SN 2018bcc is a luminous transient with a rapid rise to peak powered by shock interaction inside a dense and He-rich CSM. Its spectra do not support the existence of two Type Ibn spectral classes. We also note the remarkable observational match to pulsational pair instability SN models.
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Abstract Our purpose was to estimate the incidence of unicompartmental knee arthroplasty in the United States. Three major implant manufacturers provided data over an 8-year period from 1998 to 2005. ...In addition, a database from 44 hospitals was used to derive national estimates for implants manufactured by all other companies. The incidence of unicompartmental knee arthroplasty ranged from 6570implants in 1998 to 44 990 in 2005. Unicompartmental knee arthroplasty increased at an average rate of 32.5% during the study period compared with a 9.4% average increase in rate of total knee arthroplasty over the same period. Although unicompartmental arthroplasty is growing at triple the rate of total knee arthroplasty in the United States, the data suggest that unicompartmental implants currently account for less than 8% of all knee arthroplasty procedures.
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Ginseng replant disease (GRD) prevents the successful production of a second ginseng crop on the same ground even decades after the first crop. A study was initiated in 2013 to compare the efficacy ...of fumigants and biofumigants at two sites: (1) a replant garden planted to ginseng one year after a crop had been harvested, and (2) a non-replant site in which ginseng had never been grown. Treatments included chloropicrin and metam-sodium fumigants covered in totally impermeable film (TIF), un-tarped metam-sodium, modified mustard seed meal (MSM), and a mustard-capsaicin product (MC), and both a tarped and un-tarped control. Treatments were applied in June and July 2013 and ginseng seeded in August 2013. Plant stand was assessed monthly throughout the trial beginning after germination in spring 2014, and yield and quality were assessed at harvest in 2016 (replant site) and 2017 (non-replant site). At the replant site, plant stand declined rapidly in the un-tarped control, MSM, and MC treatments in the seedling year with no roots surviving to harvest. Although all plots had some disease at harvest, chloropicrin, metam-sodium, and the tarped control significantly improved yield. Disease pressures were low at the non-replant site and there were no consistent differences among treatments. Using Koch's postulates, the cause of the rot in the replanted plot was confirmed to be Ilyonectria mors-panacis, although other factors are likely involved in the disease. Plant parasitic nematodes were not present in the replant site suggesting they may not be important factors in replant disease severity.
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The PLATeau Observatory (PLATO) is an automated self-powered astrophysical observatory that was deployed to Dome A, the highest point on the Antarctic plateau, in 2008 January. PLATO consists of a ...suite of site-testing instruments designed to quantify the benefits of the Dome A site for astronomy, and science instruments designed to take advantage of the unique observing conditions. Instruments include CSTAR, an array of optical telescopes for transient astronomy; Gattini, an instrument to measure the optical sky brightness and cloud cover statistics; DASLE, an experiment to measure the statistics of the meteorological conditions within the near-surface layer; Pre-HEAT, a submillimeter tipping radiometer measuring the atmospheric transmission and water vapor content and performing spectral line imaging of the Galactic plane; and Snodar, an acoustic radar designed to measure turbulence within the near-surface layer. PLATO has run completely unattended and collected data throughout the winter 2008 season. Here we present a detailed description of the PLATO instrument suite and preliminary results obtained from the first season of operation.
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