Search for the Neutron Decay n→\rightarrow X+γ\gamma where X is a dark matter particle

In a recent paper submitted to Physical Review Letters, Fornal and Grinstein have suggested that the discrepancy between two different methods of neutron lifetime measurements, the beam and bottle methods can be explained by a previously unobserved dark matter decay mode, n$\rightarrow$ X+$\gamma$ where X is a dark matter particle. We have performed a search for this decay mode over the allowed range of energies of the monoenergetic gamma ray for X to be a dark matter particle. We exclude the possibility of a sufficiently strong branch to explain the lifetime discrepancy with greater than 4 sigma confidence.Comment: 6 pages 3 figure

Resistance to wheat rusts identified in wheat/Amblyopyrum muticum chromosome introgressions

© 2020 The Authors. Crop Science © 2020 Crop Science Society of America Wheat (Triticum aestivum L.) rusts are a worldwide production problem. Plant breeders have used genetic resistance to combat these fungi. However, single-gene resistance is rapidly overcome as a result of frequent occurrence of new virulent fungal strains. Thus, a supply of new resistance sources is continually needed, and new resistance sources are limited within hexaploid wheat genetic stocks. Wild relatives are able to be a resource for new resistance genes but are hindered because of chromosome incapability with domesticated wheats. Twenty-eight double-haploid hexaploid wheat/Amblyopyrum muticum (Boiss.) Eig introgression lines, with introgressions covering the majority of the T genome, were evaluated for resistance to Puccinia triticina Erikss., P. graminis Pers.:Pers. f.sp. tritici Erikss. & E. Henning, and P. striiformis Westend. f.sp. tritici Erikss. At the seedling level, four lines were resistant to races of P. triticina, six lines were resistant to P. graminis, and 15 lines were resistant to P. striiformis. At the adult stage, 16 lines were resistant to P. triticina. Line 355 had resistance to all three rusts and line 161 had resistance to all tested races of P. triticina. Some of these lines will require further work to reduce the size of the introgressed segment; however, lines 92 and 355 have very small fragments and can be used directly as new resistance donors

Status of the UCNτ experiment

The neutron is the simplest nuclear system that can be used to probe the structure of the weak interaction and search for physics beyond the standard model. Measurements of neutron lifetime and β-decay correlation coefficients with precisions of 0.02% and 0.1%, respectively, would allow for stringent constraints on new physics. The UCNτ experiment uses an asymmetric magneto-gravitational UCN trap with in situ counting of surviving neutrons to measure the neutron lifetime, τ_n = 877.7s (0.7s)_(stat) (+0.4/−0.2s)_(sys). We discuss the recent result from UCNτ, the status of ongoing data collection and analysis, and the path toward a 0.25 s measurement of the neutron lifetime with UCNτ

Seasonal Distribution, Aggregation, and Habitat Selection of Common Carp in Clear Lake, Iowa

The common carp Cyprinus carpio is widely distributed and frequently considered a nuisance species outside its native range. Common carp are abundant in Clear Lake, Iowa, where their presence is both a symptom of degradation and an impediment to improving water quality and the sport fishery. We used radiotelemetry to quantify seasonal distribution, aggregation, and habitat selection of adult and subadult common carp in Clear Lake during 2005–2006 in an effort to guide future control strategies. Over a 22-month period, we recorded 1,951 locations of 54 adults and 60 subadults implanted with radio transmitters. Adults demonstrated a clear tendency to aggregate in an offshore area during the late fall and winter and in shallow, vegetated areas before and during spring spawning. Late-fall and winter aggregations were estimated to include a larger percentage of the tracked adults than spring aggregations. Subadults aggregated in shallow, vegetated areas during the spring and early summer. Our study, when considered in combination with previous research, suggests repeatable patterns of distribution, aggregation, and habitat selection that should facilitate common carp reduction programs in Clear Lake and similar systems

Search for the Neutron Decay n → X + γ, Where X is a Dark Matter Particle

Fornal and Grinstein recently proposed that the discrepancy between two different methods of neutron lifetime measurements, the beam and bottle methods, can be explained by a previously unobserved dark matter decay mode, n → X + γ. We perform a search for this decay mode over the allowed range of energies of the monoenergetic γray for X to be dark matter. A Compton-suppressed high-purity germanium detector is used to identify γrays from neutron decay in a nickel-phosphorous-coated stainless-steel bottle. A combination of Monte Carlo and radioactive source calibrations is used to determine the absolute efficiency for detecting γ rays arising from the dark matter decay mode. We exclude the possibility of a sufficiently strong branch to explain the lifetime discrepancy with 97% confidence

Search for the Neutron Decay \u3cem\u3en\u3c/em\u3e → \u3cem\u3eX\u3c/em\u3e+\u3cem\u3eγ\u3c/em\u3e, Where \u3cem\u3eX\u3c/em\u3e is a Dark Matter Particle

Fornal and Grinstein recently proposed that the discrepancy between two different methods of neutron lifetime measurements, the beam and bottle methods, can be explained by a previously unobserved dark matter decay mode, n → X+γ. We perform a search for this decay mode over the allowed range of energies of the monoenergetic γ ray for X to be dark matter. A Compton-suppressed high-purity germanium detector is used to identify γ rays from neutron decay in a nickel-phosphorous-coated stainless-steel bottle. A combination of Monte Carlo and radioactive source calibrations is used to determine the absolute efficiency for detecting γ rays arising from the dark matter decay mode. We exclude the possibility of a sufficiently strong branch to explain the lifetime discrepancy with 97% confidence

Resistance to Wheat streak mosaic virus identified in synthetic wheat lines

Citation: Shoup Rupp, J. L., Simon, Z. G., Gillett-Walker, B., & Fellers, J. P. (2014). Resistance to Wheat streak mosaic virus identified in synthetic wheat lines. Retrieved from http://krex.ksu.eduWheat streak mosaic virus (WSMV) is an important pathogen in wheat that causes significant yield losses each year. WSMV is typically controlled using cultural practices such as the removal of volunteer wheat. Genetic resistance is limited. Until recently, no varieties have been available with major resistance genes to WSMV. Two resistance genes have been derived from Thinopyrum intermedium through chromosome engineering, while a third gene was transferred from bread wheat through classical breeding. New sources of resistance are needed and synthetic wheat lines provide a means of accessing genetic variability in wheat progenitors. A collection of wheat synthetic lines was screened for WSMV resistance. Four lines, 07-SYN-27, -106, -164, and -383 had significant levels of resistance. Resistance was effective at 18 °C and virus accumulation was similar to the resistant control, WGGRC50 containing Wsm1. At 25 °C, resistance was no longer effective and virus accumulation was similar to the susceptible control, Tomahawk

Knowing the enemy: ant behavior and control in a pediatric hospital of Buenos Aires

Ant control is difficult in systems even where a variety of control strategies and compounds are allowed; in sensitive places such as hospitals, where there are often restrictions on the methods and toxicants to be applied, the challenge is even greater. Here we report the methods and results of how we faced this challenge of controlling ants in a pediatric hospital using baits. Our strategy was based on identifying the species present and analyzing their behavior. On the one hand, we evaluated outdoors in the green areas of the hospital, the relative abundance of ant genera, their food preferences and the behavioral dominances. On the other hand, control treatments were performed using separately two boron compounds added to sucrose solution which was not highly concentrated to avoid constrains due to the viscosity. Most of the species in the food preference test accepted sugary food; only one species was recorded to visit it less than the protein foods. This result was consistent with the efficacy of control treatments by sugary baits within the rooms. For species that showed good acceptance of sugar solutions in the preference test outdoors, sugar bait control indoors was 100& effective. Conversely, for the only species that foraged significantly less on sugar food, the bait treatment was ineffective. This work reveals the importance of considering the behavior and feeding preferences of the species to be controlled by toxic baits.Fil: Josens, Roxana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Sola, Francisco Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Marchisio, Nahuel Matías. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Di Renzo, María Agostina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental. Laboratorio del Grupo de Estudio de Insectos Sociales; ArgentinaFil: Giacometti, Alina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentin