We confirm the recent prediction that interstitial protium may act as a shallow donor in zinc oxide, by direct spectroscopic observation of its muonium counterpart. On implantation into ZnO, positive ...muons--chemically analogous to protons in this context--form paramagnetic centers below about 40 K. The muon-electron contact hyperfine interaction, as well as the temperature and activation energy for ionization, imply a shallow level. Similar results for the cadmium chalcogenides suggest that such shallow donor states are generic to the II-VI compounds. The donor level depths should serve as a guide for the electrical activity of interstitial hydrogen.
Two experiments were conducted to investigate the effects of equine chorionic gonadotropin (eCG) at progestin removal and gonadotropin-releasing hormone (GnRH) at timed artificial insemination (TAI) ...on ovarian follicular dynamics (Experiment 1) and pregnancy rates (Experiment 2) in suckled Nelore (
Bos indicus) cows. Both experiments were 2
×
2 factorials (eCG or No eCG, and GnRH or No GnRH), with identical treatments. In Experiment 1, 50 anestrous cows, 134.5
±
2.3 d postpartum, received a 3
mg norgestomet ear implant sc, plus 3
mg norgestomet and 5
mg estradiol valerate im on Day 0. The implant was removed on Day 9, with TAI 54
h later. Cows received 400 IU eCG or no further treatment on Day 9 and GnRH (100
μg gonadorelin) or no further treatment at TAI. Treatment with eCG increased the growth rate of the largest follicle from Days 9 to 11 (means
±
SEM, 1.53
±
0.1 vs. 0.48
±
0.1
mm/d; P
<
0.0001), its diameter on Day 11 (11.4
±
0.6 vs. 9.3
±
0.7
mm; P
=
0.03), as well as ovulation rate (80.8% vs. 50.0%, P
=
0.02), whereas GnRH improved the synchrony of ovulation (72.0
±
1.1 vs. 71.1
±
2.0
h). In Experiment 2 (n
=
599 cows, 40 to 120 d postpartum), pregnancy rates differed (P
=
0.004) among groups (27.6%, 40.1%, 47.7%, and 55.7% for Control, GnRH, eCG, and eCG
+
GnRH groups). Both eCG and GnRH improved pregnancy rates (51.7% vs. 33.8%, P
=
0.002; and 48.0% vs 37.6%, P
=
0.02, respectively), although their effects were not additive (no significant interaction). In conclusion, eCG at norgestomet implant removal increased the growth rate of the largest follicle (LF) from implant removal to TAI, the diameter of the LF at TAI, and rates of ovulation and pregnancy rates. Furthermore, GnRH at TAI improved the synchrony of ovulations and pregnancy rates in postpartum Nelore cows treated with a norgestomet-based TAI protocol.
The lifetime of nitrogen oxides (NOx) affects the concentration and distribution of NOx and the spatial patterns of nitrogen deposition. Despite its importance, the lifetime of NOx is poorly ...constrained in rural and remote continental regions. We use measurements from a site in central Alabama during the Southern Oxidant and Aerosol Study (SOAS) in summer 2013 to provide new insights into the chemistry of NOx and NOx reservoirs. We find that the lifetime of NOx during the daytime is controlled primarily by the production and loss of alkyl and multifunctional nitrates (ΣANs). During SOAS, ΣAN production was rapid, averaging 90 ppt h−1 during the day, and occurred predominantly during isoprene oxidation. Analysis of the ΣAN and HNO3 budgets indicate that ΣANs have an average lifetime of under 2 h, and that approximately 45 % of the ΣANs produced at this site are rapidly hydrolyzed to produce nitric acid. We find that ΣAN hydrolysis is the largest source of HNO3 and the primary pathway to permanent removal of NOx from the boundary layer in this location. Using these new constraints on the fate of ΣANs, we find that the NOx lifetime is 11 ± 5 h under typical midday conditions. The lifetime is extended by storage of NOx in temporary reservoirs, including acyl peroxy nitrates and ΣANs.
Objective: The research tested the efficacy of planning and partner-based interventions to promote physical activity over six months. Method: Local government (council) employees (N = 257) were ...randomly allocated to one of four conditions (collaborative implementation intentions; partner-only; implementation intentions; control group) before completing measures at baseline and follow-ups at 1, 3 and 6 months. Outcome measures comprised validated self-report measures of physical activity: the International Physical Activity Questionnaire (IPAQ; Craig et al., 2003) and Self-Report Walking and Exercise Tables (SWET; Prestwich et al., 2012); psychosocial mediators (enjoyment, intention, self-efficacy, social influence); weight and waist size (baseline and 6 months only). Results: As well as losing the most weight, there was evidence that participants in the collaborative implementation-intention group were more physically active than each of the other three groups at 1-, 3- and 6-month follow-ups. Those in the implementation-intention and partner-only conditions did not outperform the control group on most measures. Conclusion: Collaborative implementation intentions represent a potentially useful intervention to change important health behaviors that help reduce weight.
Background: Studies have linked asthma death to either increased or decreased use of medical services. Methods: A population based case-control study of asthma deaths in 1994–8 was performed in 22 ...English, six Scottish, and five Welsh health authorities/boards. All 681 subjects who died were under the age of 65 years with asthma in Part I on the death certificates. After exclusions, 532 hospital controls were matched to 532 cases for age, district, and date of asthma admission/death. Data were extracted blind from primary care records. Results: The median age of the subjects who died was 53 years; 60% of cases and 64% of controls were female. There was little difference in outpatient attendance (55% and 55%), hospital admission for asthma (51% and 54%), and median inpatient days (20 days and 15 days) in the previous 5 years. After mutual adjustment and adjustment for sex, using conditional logistic regression, three variables were independently associated with asthma death: fewer general practice contacts (odds ratio 0.82 (95% confidence interval (CI) 0.74 to 0.91) per 5 contacts) in the previous year, more home visits (1.14 (95% CI 1.08 to 1.21) per visit) in the previous year, and fewer peak expiratory flow recordings (0.83 (95% CI 0.74 to 0.92) per occasion) in the previous 3 months. These associations were similar after adjustment for markers of severity, psychosocial factors, systemic steroids, short acting bronchodilators and antibiotics, although the association with peak flow was weakened and just lost significance. Conclusion: Asthma death is associated with less use of primary care services. Both practice and patient factors may be involved and a better understanding of these may offer possibilities for reducing asthma death.
Previous studies on Combretum leprosum, a tree growing in the Northeastern states of Brazil, have shown antinociceptive effects of the ethanol extract of its leaves and bark, but studies examining ...its constituents are rare. The objective of this study was to evaluate the antinociceptive effect of the hydroalcoholic fraction (HF) of one of its constituents, the flavonoid (-) epicatechin (EPI), administered orally to mice (20-30 g) in models of chemical nociception, and the possible mechanisms involved. Different doses of HF (62.5 to 500 mg/kg) and EPI (12.5 to 50 mg/kg) were evaluated in models of abdominal writhing, glutamate, capsaicin, and formalin in animals pretreated with different antagonists: naloxone, ondansetron, yohimbine, ketanserin, pindolol, atropine, and caffeine in the abdominal writhing test. To determine the role of nitric oxide, the animals were pretreated with L-arginine (600 mg/kg, ip) in the glutamate test. The HF was effective (P < 0.05) in all protocols at different doses and EPI was effective in the abdominal writhing, capsaicin and glutamate tests (P < 0.05) at doses of 25 and 50 mg/kg. However, in the formalin test it was only effective in the second phase at a dose of 25 mg/kg. The antinociceptive effect of HF was inhibited when HF was associated with yohimbine (0.15 mg/kg), ketanserine (0.03 mg/kg), and L-arginine (600 mg/kg), but not with the other antagonists. HF and EPI were effective in models of chemical nociception, with the suggested participation of the adrenergic, serotonergic and nitrergic systems in the antinociceptive effect of HF.
Abstract The effects of oleanolic acid (OA) on ABCB1 and ABCC1 activities were studied in a cell line constitutively expressing both proteins. It was observed that OA did not alter ABCB1 activity, ...but inhibited the activity of ABCC1 protein. This inhibition was reversible and only occurred in the presence of OA. In addition, OA did not alter the expression of ABCC1 mRNA. These results suggest that OA could be a good choice in the treatment of MDR tumours, either as a chemotherapic itself in tumours bearing ABCB1, or as an adjuvant in the chemotherapy of ABCC1 expressing tumours.
Global change research demands a convergence among academic disciplines to understand complex changes in Earth system function. Limitations related to data usability and computing infrastructure, ...however, present barriers to effective use of the research tools needed for this cross-disciplinary collaboration. To address these barriers, we created a computational platform that pairs meteorological data and site-level ecosystem characterizations from the National Ecological Observatory Network (NEON) with the Community Terrestrial System Model (CTSM) that is developed with university partners at the National Center for Atmospheric Research (NCAR). This NCAR–NEON system features a simplified user interface that facilitates access to and use of NEON observations and NCAR models. We present preliminary results that compare observed NEON fluxes with CTSM simulations and describe how the collaboration between NCAR and NEON that can be used by the global change research community improves both the data and model. Beyond datasets and computing, the NCAR–NEON system includes tutorials and visualization tools that facilitate interaction with observational and model datasets and further enable opportunities for teaching and research. By expanding access to data, models, and computing, cyberinfrastructure tools like the NCAR–NEON system will accelerate integration across ecology and climate science disciplines to advance understanding in Earth system science and global change.
Abstract Objective To investigate the association between bronchodilator treatment and death from asthma. Design Case-control study. Setting 33 health authorities or health boards in Great Britain. ...Participants 532 patients under age 65 who died from asthma and 532 controls with a hospital admission for asthma matched for period, age, and area. Main outcome measures Odds ratios for deaths from asthma associated with prescription of bronchodilators and other treatment, with sensitivity analyses adjusting for age at onset, previous hospital admissions, associated chronic obstructive lung disease, and number of other drug categories. Results After full adjustment, there were no significant associations with drugs prescribed in the 4-12 months before the index date. For prescriptions in the 1-5 years before, mortality was positively associated with inhaled short acting β2 agonists (odds ratio 2.05, 95% confidence interval 1.26 to 3.33) and inversely associated with antibiotics (0.59, 0.39 to 0.89). The former association seemed to be confined to those aged 45-64, and the association with antibiotics was more pronounced in those under 45. Significant age interactions across all periods suggested inverse associations with oral steroids confined to the under 45 age group. An inverse association with long acting β2 agonists and a positive association with methylxanthines in the 1-5 year period were non-significant. Conclusion There was no evidence of adverse effects on mortality with medium to long term use of inhaled long acting β2 agonist drugs. The association with short acting β2 agonists has several explanations, only one of which may be a direct adverse effect.
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