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Room Decontamination Using Ionized Hydrogen Peroxide Fog and Mist Reduces Hatching Rates of Syphacia obvelata Ova

This study evaluated the efficacy of ionized hydrogen peroxide (iHP) fog and mist for environmental and surface decontamination of Syphacia obvelata ova in rodent rooms. Ova were collected by perianal tape impression from S. obvelata infected mice. In experiment 1, ova were exposed to iHP using a whole-room fogging decontamination system with a 15 min initial fog application cycle in unoccupied rodent rooms. Ova were removed from the fogged environment after a 15 min, 30 min, 90 min, or 240 min iHP exposure time. In experiment 2, a second cohort of ova were exposed to iHP using the whole-room fogging decontamination system. Ova were removed after 3, 4 or 6 continuous fog application cycles with 45 min dwelling time between each cycle and 15 h dwelling time for the last time point. In experiment 3, a third set of ova was exposed to an iHP surface misting unit with 1, 2, or 3 iHP mist applications. A 7 min contact time followed each application. After exposure, ova were incubated in a hatching medium for 6 h. Control ova were maintained at room temperature without iHP exposure before incubation in the hatching medium. After incubation, the number of ova hatched was assessed by microscopic examination. For experiment 1, results ranged from 46% to 57% of exposed ova hatched. For experiment 2, results ranged from 43% to 49% of ova hatched. For experiment 3, 37% to 46% of exposed ova hatched. Conversely, for the control groups above 80% of ova hatched for all 3 experiments. These data suggest that exposure to iHP fog and mist has variable effectiveness in reducing viability of S. obvelata ova at the time points tracked. Further studies are needed to identify iHP exposures that will further reduce or eliminate the hatching of rodent pinworm ova

Effects of Vegetation, Corridor Width and Regional Land Use on Early Successional Birds on Powerline Corridors

Powerline rights-of-way (ROWs) often provide habitat for early successional bird species that have suffered long-term population declines in eastern North America. To determine how the abundance of shrubland birds varies with habitat within ROW corridors and with land use patterns surrounding corridors, we ran Poisson regression models on data from 93 plots on ROWs and compared regression coefficients. We also determined nest success rates on a 1-km stretch of ROW. Seven species of shrubland birds were common in powerline corridors. However, the nest success rates for prairie warbler (Dendroica discolor) and field sparrow (Spizella pusilla) were <21%, which is too low to compensate for estimated annual mortality. Some shrubland bird species were more abundant on narrower ROWs or at sites with lower vegetation or particular types of vegetation, indicating that vegetation management could be refined to favor species of high conservation priority. Also, several species were more abundant in ROWs traversing unfragmented forest than those near residential areas or farmland, indicating that corridors in heavily forested regions may provide better habitat for these species. In the area where we monitored nests, brood parasitism by brown-headed cowbirds (Molothrus ater) occurred more frequently close to a residential area. Although ROWs support dense populations of shrubland birds, those in more heavily developed landscapes may constitute sink habitat. ROWs in extensive forests may contribute more to sustaining populations of early successional birds, and thus may be the best targets for habitat management

The Science Performance of JWST as Characterized in Commissioning

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures; https://iopscience.iop.org/article/10.1088/1538-3873/acb29

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure &lt; 100 mmHg (n = 1127), estimated glomerular filtration rate &lt; 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Going off topics to demix quark and gluon jets in alphaS extractions

Quantum chromodynamics is the theory of the strong interaction between quarks and gluons; the coupling strength of the interaction, α$_{S}$, is the least precisely-known of all interactions in nature. An extraction of the strong coupling from the radiation pattern within jets would provide a complementary approach to conventional extractions from jet production rates and hadronic event shapes, and would be a key achievement of jet substructure at the Large Hadron Collider (LHC). Presently, the relative fraction of quark and gluon jets in a sample is the limiting factor in such extractions, as this fraction is degenerate with the value of α$_{S}$ for the most well-understood observables. To overcome this limitation, we apply recently proposed techniques to statistically demix multiple mixtures of jets and obtain purified quark and gluon distributions based on an operational definiton. We illustrate that studying quark and gluon jet substructure separately can significantly improve the sensitivity of such extractions of the strong coupling. We also discuss how using machine learning techniques or infrared- and collinear-unsafe information can improve the demixing performance without the loss of theoretical control. While theoretical research is required to connect the extract topics with the quark and gluon objects in cross section calculations, our study illustrates the potential of demixing to reduce the dominant uncertainty for the α$_{S}$ extraction from jet substructure at the LHC.Quantum chromodynamics is the theory of the strong interaction between quarks and gluons; the coupling strength of the interaction, $\alpha_S$, is the least precisely-known of all interactions in nature. An extraction of the strong coupling from the radiation pattern within jets would provide a complementary approach to conventional extractions from jet production rates and hadronic event shapes, and would be a key achievement of jet substructure at the Large Hadron Collider (LHC). Presently, the relative fraction of quark and gluon jets in a sample is the limiting factor in such extractions, as this fraction is degenerate with the value of $\alpha_S$ for the most well-understood observables. To overcome this limitation, we apply recently proposed techniques to statistically demix multiple mixtures of jets and obtain purified quark and gluon distributions based on an operational definition. We illustrate that studying quark and gluon jet substructure separately can significantly improve the sensitivity of such extractions of the strong coupling. We also discuss how using machine learning techniques or infrared- and collinear-unsafe information can improve the demixing performance without the loss of theoretical control. While theoretical research is required to connect the extract topics with the quark and gluon objects in cross section calculations, our study illustrates the potential of demixing to reduce the dominant uncertainty for the $\alpha_S$ extraction from jet substructure at the LHC

Going off topics to demix quark and gluon jets in αS extractions

Abstract : Quantum chromodynamics is the theory of the strong interaction between quarks and gluons; the coupling strength of the interaction, αS, is the least precisely-known of all interactions in nature. An extraction of the strong coupling from the radiation pattern within jets would provide a complementary approach to conventional extractions from jet production rates and hadronic event shapes, and would be a key achievement of jet substructure at the Large Hadron Collider (LHC). Presently, the relative fraction of quark and gluon jets in a sample is the limiting factor in such extractions, as this fraction is degenerate with the value of αS for the most well-understood observables. To overcome this limitation, we apply recently proposed techniques to statistically demix multiple mixtures of jets and obtain purified quark and gluon distributions based on an operational definiton. We illustrate that studying quark and gluon jet substructure separately can significantly improve the sensitivity of such extractions of the strong coupling. We also discuss how using machine learning techniques or infrared- and collinear-unsafe information can improve the demixing performance without the loss of theoretical control. While theoretical research is required to connect the extract topics with the quark and gluon objects in cross section calculations, our study illustrates the potential of demixing to reduce the dominant uncertainty for the αS extraction from jet substructure at the LHC

The early phase change Gene in Maize

Recessive mutations of the early phase change (epc) gene in maize affect several aspects of plant development. These mutations were identified initially because of their striking effect on vegetative phase change. In certain genetic backgrounds, epc mutations reduce the duration of the juvenile vegetative phase of development and cause early flowering, but they have little or no effect on the number of adult leaves. Except for a transient delay in leaf production during germination, mutant plants initiate leaves at a normal rate both during and after embryogenesis. Thus, the early flowering phenotype of epc mutations is explained completely by their effect on the expression of the juvenile phase. The observation that epc mutations block the rejuvenation of leaf primordia in excised shoot apices supports the conclusion that epc is required for the expression of juvenile traits. This phenotype suggests that epc functions normally to promote the expression of the juvenile phase of shoot development and to suppress the expression of the adult phase and that floral induction is initiated by the transition to the adult phase. epc mutations are epistatic to the gibberellin-deficient mutation dwarf1 and interact additively with the dominant gain-of-function mutations Teopod1, Teopod2, and Teopod3. Genetic backgrounds that enhance the mutant phenotype of epc demonstrate that, in addition to its role in phase change, epc is required for the maintenance of the shoot apical meristem, leaf initiation, and root initiation