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Cosmogenic-neutron activation of TeO2 and implications for neutrinoless double- Ī² decay experiments
Flux-averaged cross sections for cosmogenic-neutron activation of natural tellurium were measured using a neutron beam containing neutrons of kinetic energies up to ā¼800 MeV and having an energy spectrum similar to that of cosmic-ray neutrons at sea level. Analysis of the radioisotopes produced reveals that Ag110m will be a dominant contributor to the cosmogenic-activation background in experiments searching for neutrinoless double-Ī² decay of Te130, such as the Cryogenic Underground Observatory for Rare Events (CUORE) and the Sudbury Neutrino Observatory Plus (SNO+). An estimate of the cosmogenic-activation background in the CUORE experiment has been obtained using the results of this measurement and cross-section measurements of proton activation of tellurium. Additionally, the measured cross sections in this work are also compared with results from semiempirical cross-section calculations
The effect of different sowing patterns and deficit irrigation management on yield and agronomic characteristics of sweet corn
Water stress restricts crop yields in both the arid and semi-arid zones of the world. The responses of sweet corn (Zea mays) to irrigation frequency and sowing patterns were studied in the field from December 2005 to December 2006. This research was laid out in split plot, with water quantity as main plot and sowing patterns as subplot in three replications. The treatments consisted of two irrigation times (6 and 10 days) and six levels of planting patterns (full irrigation in single row, changeable alternative irrigation in single row, full irrigation in double row, changeable alternative irrigation in double row, fixed alternative irrigation in single row and fixed alternative irrigation in double row pattern). The results show that, both biomass and stem fresh weight was affected by irrigation regimes, with normal irrigation treatments accounting for the highest. The effect of sowing patterns on all measured traits were significant at 1% level with the exception of plant height, ear depth, number of seeds/ear row and number of seeds/row. The results further demonstrate that water consumption in alternative furrow irrigation trait was worthwhile (35%) in contrast with control treatment. Although, the degree of decline in yield when compared with the control group was 3.4 and 5.2%, respectively, it was not statistically significant. The practice of alternative furrow irrigation may be recommended as a suitable farming method in northern Iran due to the benefits associated with it in terms of weeds reduction and providing soil ventilation.Keywords: Deficit irrigation, double row, furrows irrigation, planting pattern, sweet cor
A microwave metamaterial with integrated power harvesting functionality
We present the design and experimental implementation of a power harvesting metamaterial. A maximum of 36.8% of the incident power from a 900 MHz signal is experimentally rectified by an array of metamaterial unit cells. We demonstrate that the maximum harvested power occurs for a resistive load close to 70 Ī© in both simulation and experiment. The power harvesting metamaterial is an example of a functional metamaterial that may be suitable for a wide variety of applications that require power delivery to any active components integrated into the metamaterial. Ā© 2013 AIP Publishing LLC
Enhancement of Gap Junction Function During Acute Myocardial Infarction Modifies Healing and Reduces Late Ventricular Arrhythmia Susceptibility
Objectives: To investigate the effects of enhancing gap junction (GJ) coupling during acute myocardial infarction (MI) on the healed infarct scar morphology and late post-MI arrhythmia susceptibility. Background: Increased heterogeneity of myocardial scarring after MI is associated with greater arrhythmia susceptibility. We hypothesized that short-term enhancement of GJ coupling during acute MI can produce more homogeneous infarct scars, reducing late susceptibility to post-MI arrhythmias. Methods: Following arrhythmic characterisation of the rat 4-week post-MI model (n=24), a further 27 Sprague-Dawley rats were randomised to receive rotigaptide to enhance GJ coupling (n=13) or saline control (n=14) by osmotic minipump immediately prior to, and for the first 7 days following surgical MI. At 4 weeks post-MI, hearts were explanted for ex vivo programmed electrical stimulation (PES) and optical mapping. Heterogeneity of infarct border zone (IBZ) scarring was quantified by histomorphometry. Results: Despite no detectable difference in infarct size at 4 weeks post-MI, rotigaptide-treated hearts had reduced arrhythmia susceptibility during PES (Inducibility score: rotigaptide 2.40.8, control 5.00.6, p=0.02) and less heterogeneous IBZ scarring (standard deviation of IBZ Complexity Score: rotigaptide 1.10.1, control 1.40.1, p=0.04), associated with an improvement in IBZ conduction velocity (rotigaptide 43.13.4 cm/s, control 34.82.0 cm/s, p=0.04). Conclusions: Enhancement of GJ coupling for only 7 days at the time of acute MI produced more homogeneous IBZ scarring and reduced arrhythmia susceptibility at 4 weeks post-MI. Short-term GJ modulation at the time of MI may represent a novel treatment strategy to modify the healed infarct scar morphology and reduce late post-MI arrhythmic risk
In-vitro application of pentoxifylline preserved ultrastructure of spermatozoa after vitrification in asthenozoospermic patients
Abstract
PURPOSE:
To evaluate the effect of in vitro application of pentoxifylline (PX) on sperm parameters and ultrastructure after vitrification in asthenozoospermic patients.
MATERIALS AND METHODS:
A total of 30 asthenozoospermic semen samples (aged 25-45 years) were divided into four groups before vitrification, after vitrification, control (without PX) and experimental (with PX). In experimental group, each sample was exposed for 30 min to 3.6mmol/l PX and the control group without any treatment apposing in 370C for 30 min. After incubation, the samples were washed and analyzed again. Vitrification was done according to straw method. Eosin-nigrosin and Papanicolaou staining were applied for assessment of sperm viability and morphology, respectively. The samples without PX and post treatment with PX were assessed by transmission electron microscopy (TEM).
RESULTS:
A significant decrease in sperm motility (P ā¤ .001), morphology (11.47 Ā± 2.9 versus 6.73 Ā± 2.01) and viability (73.37 Ā± 6.26 versus 54.67 Ā± 6.73) was observed post vitrification, but sperm motility (19.85 Ā± 4.75 versus 32.07 Ā± 5.58, P ā¤ .001) was increased significantly following application of PX. This drug had no significant (P >.05) detrimental neither negative effect on ultrastructure acrosome, plasma membrane and coiled tail statues of spermatozoa.
CONCLUSION:
Vitrification had detrimental effects on sperm parameters, but PX reversed detrimental effects on sperm motility. However, PX had no alteration on ultrastructure morphology of human spermatozoa after vitrification
Reported Acquisition Practices of Australian Dog Owners
In Australia, the UK and the US dog ownership is prevalent with an estimated 40% ofAustralian households, 25% of UK households, and 50% of US households owning a dog. Onceacquired, a dog usually becomes a family companion so, unlike a faulty product, it can rarely bereturned or resold without some emotional impact on both the acquirer and the dog. Regarding thereality of dog relinquishment, there is a growing need for cross-disciplinary research that considershow dog owners are making their acquisition choices and, if prioritising different attributes, leads tomore optimal acquisition choices. This research collected data from 2840 dog owners via an onlinesurvey and examines how owners prioritised various attributes when acquiring their latest dog.The Pearson-Blotchky analysis of survey results show owners are split into two groups, with eachgroup prioritising different attributes or characteristics in their search for a new dog. The first groupare those dog owners who prioritised: the ability to rescue a dog, how compatible the dog wason the first meeting, and how compatible they believed the dog would be with their household.The second group are those owners who prioritised: a dogās morphology, temperament predictability,and breeding practices. While each group prioritised different attributes, neither group madesubstantially more optimal acquisition choices in terms of overall satisfaction with the dog that theyultimately selected
Hypothalamic actions of neuromedin U.
The central nervous system and gut peptide neuromedin U (NMU) inhibits feeding after intracerebroventricular injection. This study explored the hypothalamic actions of NMU on feeding and the hypothalamo-pituitary-adrenal axis. Intraparaventricular nucleus (intra-PVN) NMU dose-dependently inhibited food intake, with a minimum effective dose of 0.1 nmol and a robust effect at 0.3 nmol. Feeding inhibition was mapped by NMU injection into eight hypothalamic areas. NMU (0.3 nmol) inhibited food intake in the PVN (0-1 h, 59 Ā± 6.9% of the control value; P < 0.001) and arcuate nucleus (0-1 h, 76 Ā± 10.4% of the control value; P < 0.05). Intra-PVN NMU markedly increased grooming and locomotor behavior and dose-dependently increased plasma ACTH (0.3 nmol NMU, 24.8 Ā± 1.9 pg/ml; saline, 11.4 Ā± 1.0; P < 0.001) and corticosterone (0.3 nmol NMU, 275.4 Ā± 40.5 ng/ml; saline, 129.4 Ā± 25.0; P < 0.01). Using hypothalamic explants in vitro, NMU stimulated CRH (100 nM NMU, 5.9 Ā± 0.95 pmol/explant; basal, 3.8 Ā± 0.39; P < 0.01) and arginine vasopressin release (100 nM NMU, 124.5 Ā± 21.8 fmol/explant; basal, 74.5 Ā± 7.6; P < 0.01). Leptin stimulated NMU release (141.9 Ā± 20.4 fmol/explant; basal, 92.9 Ā± 9.4; P < 0.01). Thus, we describe a novel role for NMU in the PVN to stimulate the hypothalamo-pituitary-adrenal axis and locomotor and grooming behavior and to inhibit feeding
The strange case of the ear and the heart: the auricular vagus nerve and its influence on cardiac control
The human ear seems an unlikely candidate for therapies aimed at improving cardiac function, but the ear and the heart share a common connection: the vagus nerve. In recent years there has been increasing interest in the auricular branch of the vagus nerve (ABVN), a unique cutaneous subdivision of the vagus distributed to the external ear. Non-invasive electrical stimulation of this nerve through the skin may offer a simple, cost-effective alternative to the established method of vagus nerve stimulation (VNS), which requires a surgical procedure and has generated mixed results in a number of clinical trials for heart failure. This review discusses the available evidence in support of modulating cardiac activity using this strange auricular nerve
Galleria mellonella infection model demonstrates high lethality of ST69 and ST127 uropathogenic E. coli.
Galleria mellonella larvae are an alternative in vivo model for investigating bacterial pathogenicity. Here, we examined the pathogenicity of 71 isolates from five leading uropathogenic E. coli (UPEC) lineages using G. mellonella larvae. Larvae were challenged with a range of inoculum doses to determine the 50% lethal dose (LD50) and for analysis of survival outcome using Kaplan-Meier plots. Virulence was correlated with carriage of a panel of 29 virulence factors (VF). Larvae inoculated with ST69 and ST127 isolates (10(4) colony-forming units/larvae) showed significantly higher mortality rates than those infected with ST73, ST95 and ST131 isolates, killing 50% of the larvae within 24 hours. Interestingly, ST131 isolates were the least virulent. We observed that ST127 isolates are significantly associated with a higher VF-score than isolates of all other STs tested (Pā¤0.0001), including ST69 (P<0.02), but one ST127 isolate (strain EC18) was avirulent. Comparative genomic analyses with virulent ST127 strains revealed an IS1 mediated deletion in the O-antigen cluster in strain EC18, which is likely to explain the lack of virulence in the larvae infection model. Virulence in the larvae was not correlated with serotype or phylogenetic group. This study illustrates that G. mellonella are an excellent tool for investigation of the virulence of UPEC strains. The findings also support our suggestion that the incidence of ST127 strains should be monitored, as these isolates have not yet been widely reported, but they clearly have a pathogenic potential greater than that of more widely recognised clones, including ST73, ST95 or ST131
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