Neutron capture cross section measurements of isotopes close to s-process branching-points are of fundamental importance for the understanding of this nucleosynthesis mechanism through which about ...50% of the elements heavier than iron are produced. We present in this contribution the results corresponding to the high resolution measurement, for first time ever, of the 80Se(n, γ) cross section, in which 98 resonances never measured before have been reported. As a consequence, ten times more precise values for the MACS have been obtained compared to previous accepted value adopted in the astrophysical KADoNiS data base.
We present the discovery and characterization of five hot and warm Jupiters—TOI-628 b(TIC 281408474; HD288842), TOI-640 b(TIC 147977348), TOI-1333 b (TIC 395171208, BD+47 3521A), TOI-1478 b ...(TIC409794137), and TOI-1601 b (TIC 139375960)—based on data from NASA’s Transiting Exoplanet Survey Satellite(TESS). The five planets were identified from the full-frame images and were confirmed through a series of photometric and spectroscopic follow-up observations by the TESS Follow-up Observing Program Working Group. The planets are all Jovian size (RP=1.01–1.77RJ) and have masses that range from 0.85 to 6.33MJ. The host stars of these systems have F and G spectral types (5595Teff 6460 K)and are all relatively bright (9.5<V<10.8, 8.2<K<9.3), making them well suited for future detailed characterization efforts. Three of the systems in our sample (TOI-640 b, TOI-1333 b, and TOI-1601 b) orbit subgiant host stars (logg<4.1). TOI-640 b is one of only three known hot Jupiters to have a highly inflated radius (RP>1.7RJ, possibly a result of its host star’s evolution) and resides on an orbit with a period longer than 5 days. TOI-628 b is the most massive, hot Jupiter discovered to date by TESS with a measured mass of-+6.310.300.28MJ and a statistically significant, nonzero orbital eccentricity of e=-+0.0740.0220.021. This planet would not have had enough time to circularize through tidal forces from our analysis, suggesting that it might be remnant eccentricity from its migration. The longest-period planet in this sample, TOI-1478 b (P=10.18 days), is a warm Jupiter in a circular orbit around a near-solar analog. NASA’s TESS mission is continuing to increase the sample of well-characterized hot and warm Jupiters, complementing its primary mission goals.
The quark structure of the f_{2}(1270) meson has, for many years, been assumed to be a pure quark-antiquark (qqover ¯) resonance with quantum numbers J^{PC}=2^{++}. Recently, it was proposed that the ...f_{2}(1270) is a molecular state made from the attractive interaction of two ρ mesons. Such a state would be expected to decay strongly to final states with charged pions due to the dominant decay ρ→π^{+}π^{-}, whereas decay to two neutral pions would likely be suppressed. Here, we measure for the first time the reaction γp→π^{0}π^{0}p, using the CEBAF Large Acceptance Spectrometer detector at Jefferson Lab for incident beam energies between 3.6 and 5.4 GeV. Differential cross sections, dσ/dt, for f_{2}(1270) photoproduction are extracted with good precision due to low backgrounds and are compared to theoretical calculations.
Much work has been carried out over the past 40
years on the oxidation of zirconium alloys used for nuclear fuel cladding, but there is no consensus as to the critical factors that control kinetics, ...even though this is vital for the design of materials for higher burn-up regimes. One unanswered question is the role of porosity in controlling oxidation. Here we show that the nature of the nanoscale porosity can be correlated to different stages of the oxidation process.
DNA arrays containing 260 unique genes involved in phase I and II metabolism, heat shock, DNA repair, inflammation, transcription, and housekeeping were used to examine gene expression patterns in ...liver and kidney in response to five classes of chemicals (polyaromatic hydrocarbons: benzo(a)pyrene, 3-methylcholanthrene; DNA alkylators: dimethylnitrosamine, ethylnitrosourea; peroxisome proliferators: diethylhexylphthalate, clofibrate; heavy metals: CdCl(2), HgCl(2); and oxidative stressors: CCl(4), bromobenzene). Time course experiments in mice were carried out in both tissues for each chemical and dose-response studies were used to further evaluate several of these chemicals. Each pair of chemicals yielded a similar pattern of gene expression distinct from the other four classes of chemicals. Both peroxisome proliferators up-regulated Cyp4a10, acyl-CoA thioesterase, and insulin-like growth factor binding protein-1, whereas the DNA alkylators altered the expression of monokine induced by gamma-interferon, the metallothioneins, p21, and several acute phase proteins. For each of the five classes of chemicals tested, several genes that were induced or repressed were common in each chemical exposure, whereas other genes were unique for that specific class of compound. Both time and dose are important factors in differentiating between chemical classes. Likewise, comparison of changes in messenger RNA expression between the kidney and liver of treated animals indicates that gene arrays may be useful in determining the comparative toxicity of chemicals in various tissues but that exposure to uncharacterized chemicals will have to be monitored in several tissues.
This paper proposes that yield stability patterns exist for multiple crops planted on the same land area over a period of years that growers can use to their advantage in planning crop management ...strategies using precision agriculture technologies. This study examines the relationship of soil elevation, slope, aspect and curvature to crop yield stability using a digital elevation model of the study area derived from a precise light detection and ranging (LIDAR) image of the farming area and surroundings. Three crop years of cotton and two crop years of corn yields were used to evaluate this hypothesis. The interpolation methods of Inverse Distance Weighted (IDW), simple Kriging and Natural Neighbor found in ESRI's ARCGIS were used to produce crop yield maps. These methods were also compared in the analysis. Simple Kriging gave the best
R
2 estimates of yield as a function of elevation, slope, curvature and aspect. When the SAS FastCluster procedure was used to group yield points together using topographical features, the resulting regression analyses
R
2 values of yield as a function of elevation, aspect, curvature and slope by cluster number were improved.
Influence of caffeine on the frequency and perception of hypoglycemia in free-living patients with type 1 diabetes.
J M Watson ,
E J Jenkins ,
P Hamilton ,
M J Lunt and
D Kerr
Bournemouth Diabetes ...and Endocrine Centre, Royal Bournemouth Hospital, U.K.
Abstract
OBJECTIVE: To examine the influence of caffeine on the frequency and perception of hypoglycemia in "free-living" patients
with type 1 diabetes. RESEARCH DESIGN AND METHODS: A total of 34 patients with type 1 diabetes were recruited for a prospective
randomized placebo-controlled double-blind study. After a lead-in phase and while adhering to a low-caffeine diet, subjects
were randomized to capsules containing either 200 mg caffeine or matched placebo with crossover at 3 months. Hypoglycemic
episodes were monitored throughout with capillary blood glucose readings and a symptom questionnaire. During the study, measurements
of blood pressure, middle cerebral artery blood velocity (a surrogate measure of cerebral blood flow), cognitive function
(via a four-choice reaction time test), HbAlc levels, and lipid profiles were taken at the beginning and end of each phase.
RESULTS: Throughout the study, no changes were evident regarding glycemic control or lipid profile. The number of symptomatic
episodes was greater with caffeine (1.3 vs. 0.9 episodes/week; P < 0.03) and was associated with more intense warning symptoms
(29 vs. 26 total symptom score; P < 0.05). For women, caffeine ingestion caused a modest pressor response (115 vs. 110 mmHg;
P < 0.01). Four-choice reaction time improved slightly with caffeine supplementation (P < 0.05). CONCLUSIONS: Ingestion of
modest amounts of caffeine enhances the intensity of hypoglycemia warning symptoms in patients with type 1 diabetes without
altering the prevailing standard of glycemic control or increasing the incidence of severe hypoglycemic episodes.
We report the measurement of a spectroscopic transit of TOI-1726c, one of two planets transiting a G-type star with V = 6.9 in the Ursa Major Moving Group (∼400 Myr). With a precise age constraint ...from cluster membership, TOI-1726 provides a great opportunity to test various obliquity excitation scenarios that operate on different timescales. By modeling the Rossiter-McLaughlin (RM) effect, we derived a sky-projected obliquity of . This result rules out a polar/retrograde orbit and is consistent with an aligned orbit for planet c. Considering the previously reported, similarly prograde RM measurement of planet b and the transiting nature of both planets, TOI-1726 tentatively conforms to the overall picture that compact multitransiting planetary systems tend to have coplanar, likely aligned orbits. TOI-1726 is also a great atmospheric target for understanding differential atmospheric loss of sub-Neptune planets (planet b 2.2 R⊕ and c 2.7 R⊕ both likely underwent photoevaporation). The coplanar geometry points to a dynamically cold history of the system that simplifies any future modeling of atmospheric escape.
PDF
