499 research outputs found
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Effect of dietary protein, selenium and temperature humidity index on reproductive traits of male rabbits in a tropical environment
The study aimed to evaluate the effects of dietary protein and selenium supplementation and temperature humidity index (THI) on male rabbit reproductive traits. Fourty eight male New Zealand White rabbits (23 ± 1.4 weeks of age) weighing 2.8 ± 1.13kg, were randomly allocated to one of six isocaloric diets (n = 8 animals/ treatment) that differed in either protein content (14g/100g, 18g/100g and 22g/100g) or selenium content (0.4 and 0.7 mg Se/ kg diet). The experimental design was 3 x 2 factorial. The study ran from April 2012 to September 2012. Significant (P= 0.001) differences observed in semen pH levels (R2 = 0.80, P= 0.010), reaction time [(libido)(R2= 0.85, P= 0.006)] and the proportion of abnormal sperm (R2= 0.44, P= 0.089) as time advanced suggesting positive relation with the changes in environmental THI. There were significant (P= 0.001) interactions between dietary protein level and Se on testis characteristics which seem to improve in Se supplemented group as dietary protein increased. The levels of THI experienced in this study were not sufficiently high enough to result in more pronounced responses on reproductive performance. Therefore there were no adverse effects on the rabbits reproductive traits fed dietary supplements in the tropics
Four-Hundred-and-Ninety-Million-Year Record of Bacteriogenic Iron Oxide Precipitation at Sea-Floor Hydrothermal Vents
Fe oxide deposits are commonly found at hydrothermal vent sites at mid-ocean ridge and back-arc sea floor spreading centers, seamounts associated with these spreading centers, and intra-plate seamounts, and can cover extensive areas of the seafloor. These deposits can be attributed to several abiogenic processes and commonly contain micron-scale filamentous textures. Some filaments are cylindrical casts of Fe oxyhydroxides formed around bacterial cells and are thus unquestionably biogenic. The filaments have distinctive morphologies very like structures formed by neutrophilic Fe oxidizing bacteria. It is becoming increasingly apparent that Fe oxidizing bacteria have a significant role in the formation of Fe oxide deposits at marine hydrothermal vents. The presence of Fe oxide filaments in Fe oxides is thus of great potential as a biomarker for Fe oxidizing bacteria in modern and ancient marine hydrothermal vent deposits. The ancient analogues of modern deep-sea hydrothermal Fe oxide deposits are jaspers. A number of jaspers, ranging in age from the early Ordovician to late Eocene, contain abundant Fe oxide filamentous textures with a wide variety of morphologies. Some of these filaments are like structures formed by modern Fe oxidizing bacteria. Together with new data from the modern TAG site, we show that there is direct evidence for bacteriogenic Fe oxide precipitation at marine hydrothermal vent sites for at least the last 490 Ma of the Phanerozoic
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Effect of milk type and processing on iodine concentration of organic and conventional winter milk at retail: implications for nutrition
Milk is the largest source of iodine in UK diets and an earlier study showed that organic summer milk had significantly lower iodine concentration than conventional milk. There are no comparable studies with winter milk or the effect of milk fat class or heat processing method. Two retail studies with winter milk are reported. Study 1 showed no effect of fat class but organic milk was 32.2% lower in iodine than conventional milk (404 vs. 595 ÎŒg/L; P < 0.001). Study 2 found no difference between conventional and Channel Island milk but organic milk contained 35.5% less iodine than conventional milk (474 vs. 306 ÎŒg/L; P < 0.001). UHT and branded organic milk also had lower iodine concentrations than conventional milk (331 ÎŒg/L; P < 0.001 and 268 ÎŒg/L: P < 0.0001 respectively). The results indicate that replacement of conventional milk by organic or UHT milk will increase the risk of sub-optimal iodine status especially for pregnant/lactating women
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The effect of Candida famata and Lactobacillus plantarum on the number of coliforms and the antibiotic resistance and virulence of Escherichia coli in the gut of broilers
This study was undertaken to determine the effect of a yeast (Candida famata) and a bacterium
(Lactobacillus plantarum), administered alone or in combination in the drinking water, on the population
of yeast, Lactobacillus sp. and coliforms, and the prevalence of antimicrobial resistance (AMR) and virulence genes in Escherichia coli (E. coli) isolated from digesta samples taken throughout the life of broiler
chickens. Male (Ross 308) day-old chicks (220) were used. C. famata (isolated from a chicken) and L. plantarum (isolated from a pig) were administered via the drinking water. Water was provided either
untreated or with C. famata (CF; 108
/ml), L. plantarum (LP; 105
â108
/ml), or a combination of CF and LP
(106
â108
/ml) in water hoppers on 2 days each week for 35 days. Administering probiotics did not affect
the growth performance in broiler chickens. No significant interactions were observed between main
effects, and neither CF nor LP had any effect on the population size of Lactobacillus sp. or coliforms.
The administration of C. famata increased the population density of yeasts in the small intestine at these
ages. The population density of coliforms, Lactobacillus sp. and yeast decreased with age (P < 0.001). There
was no significant effect of probiotics on the prevalence of phenotypic AMR and virulence genes in these
studies. The prevalence of E. coli that was resistant to ampicillin and tetracycline, as well as carrying â„3
virulence-associated genes, was greatest at the end of the starter phase (around 8 days old), before
declining through the grower and finisher phases. There was only limited evidence that administering
either CF or LP affected either the AMR or the virulence of E. coli in the bird. However, tetracycline resistance in E. coli was associated (P < 0.001, P < 0.01, P < 0.05, and P < 0.05) with the carriage of the iron
uptake systems of E. coli D, iron-repressible protein, increased serum survival and temperaturesensitive haemagglutinin genes respectively, suggesting that the accumulation of iron and the genetic
element conferring tetracycline resistance may be intertwined
Allergic Rhinitis and its Associated Co-Morbidities at Bugando Medical Centre in Northwestern Tanzania; A Prospective Review of 190 Cases.
Allergic rhinitis is one of the commonest atopic diseases which contribute to significant morbidity world wide while its epidemiology in Tanzania remains sparse. There was paucity of information regarding allergic rhinitis in our setting; therefore it was important to conduct this study to describe our experience on allergic rhinitis, associated co-morbidities and treatment outcome in patients attending Bugando Medical Centre. This was descriptive cross-sectional study involving all patients with a clinical diagnosis of allergic rhinitis at Bugando Medical Centre over a three-month period between June 2011 and August 2011. Data was collected using a pre-tested coded questionnaire and analyzed using SPSS statistical computer software version 17.0. A total of 190 patients were studied giving the prevalence of allergic rhinitis 14.7%. The median age of the patients was 8.5 years. The male to female ratio was 1:1. Adenoid hypertrophy, tonsillitis, hypertrophy of inferior turbinate, nasal polyps, otitis media and sinusitis were the most common co-morbidities affecting 92.6% of cases and were the major reason for attending hospital services. Sleep disturbance was common in children with adenoids hypertrophy (Ï2â=â28.691, Pâ=â0.000). Allergic conjunctivitis was found in 51.9%. The most common identified triggers were dust, strong perfume odors and cold weather (Pâ<â0.05). Strong perfume odors affect female than males (Ï2â=â4.583, Pâ=â0.032). In this study family history of allergic rhinitis was not a significant risk factor (P =0.423). The majority of patients (68.8%) were treated surgically for allergic rhinitis co morbidities. Post operative complication and mortality rates were 2.9% and 1.6% respectively. The overall median duration of hospital stay of in-patients was 3 days (2 - 28 days). Most patients (98.4%) had satisfactory results at discharge. The study shows that allergic rhinitis is common in our settings representing 14.7% of all otorhinolaryngology and commonly affecting children and adolescent. Sufferers seek medical services due to co-morbidities of which combination of surgical and medical treatment was needed. High index of suspicions in diagnosing allergic rhinitis and early treatment is recommended
Mineral concentrations in milk from cows fed seaweed (Saccharina latissima) under different basal protein supplementation
Sixteen multiparous Holstein cows in four blocks of 4 x 4 Latin square over 4-week experimental periods were used to study the effects of seaweed (Saccharina latissima) supplement (with/without) and protein source (rapeseed meal (RSM)/wheat distiller's grain (WDG)) on milk mineral concentrations. Dietary treatments did not affect milk production and basic composition. Feeding seaweed slightly decreased milk Ca and Cu concentrations; whilst increased (by 3.3-fold) milk iodine (I) concentration, due to a higher dietary I supply. Substitution of WDG with RSM increased feed-to-milk transfer of Ca, Na, and Se and decreased that of Mg, P, Fe, and Mn; but only reduced milk Mn and I concentrations (the latter by 27 % as a potential result of increased glucosinolate intake). Seaweed supplement can improve milk I content when cows' I supply/availability is limited, but care should be taken to avoid excess milk I contents that may pose nutritional risks for young children.Peer reviewe
Mechanical model of the ultra-fast underwater trap of Utricularia
The underwater traps of the carnivorous plants of the Utricularia species
catch their preys through the repetition of an "active slow deflation / passive
fast suction" sequence. In this paper, we propose a mechanical model that
describes both phases and strongly supports the hypothesis that the trap door
acts as a flexible valve that buckles under the combined effects of pressure
forces and the mechanical stimulation of trigger hairs, and not as a panel
articulated on hinges. This model combines two different approaches, namely (i)
the description of thin membranes as triangle meshes with strain and curvature
energy, and (ii) the molecular dynamics approach, which consists in computing
the time evolution of the position of each vertex of the mesh according to
Langevin equations. The only free parameter in the expression of the elastic
energy is the Young's modulus E of the membranes. The values for this parameter
are unequivocally obtained by requiring that the trap model fires, like real
traps, when the pressure difference between the outside and the inside of the
trap reaches about 15 kPa. Among other results, our simulations show that, for
a pressure difference slightly larger than the critical one, the door buckles,
slides on the threshold and finally swings wide open, in excellent agreement
with the sequence observed in high-speed videos.Comment: Accepted for publication in Physical Review
Pregnant women with bronchial asthma benefit from progressive muscle relaxation: A randomized, prospective, controlled trial
Background: Asthma is a serious medical problem in pregnancy and is often associated with stress, anger and poor quality of life. The aim of this study was to determine the efficacy of progressive muscle relaxation (PMR) on change in blood pressure, lung parameters, heart rate, anger and health-related quality of life in pregnant women with bronchial asthma. Methods: We treated a sample of 64 pregnant women with bronchial asthma from the local population in an 8-week randomized, prospective, controlled trial. Thirty-two were selected for PMR, and 32 received a placebo intervention. The systolic blood pressure, forced expiratory volume in the first second, peak expiratory flow and heart rate were tested, and the State-Trait Anger Expression Inventory and Health Survey (SF-36) were employed. Results: According to the intend-to-treat principle, a significant reduction in systolic blood pressure and a significant increase in both forced expiratory volume in the first second and peak expiratory flow were observed after PMR. The heart rate showed a significant increase in the coefficient of variation, root mean square of successive differences and high frequency ranges, in addition to a significant reduction in low and middle frequency ranges. A significant reduction on three of five State-Trait Anger Expression Inventory scales, and a significant increase on seven of eight SF-36 scales were observed. Conclusions: PMR appears to be an effective method to improve blood pressure, lung parameters and heart rate, and to decrease anger levels, thus enhancing health-related quality of life in pregnant women with bronchial asthma. Copyright (c) 2006 S. Karger AG, Basel
Human Impacts on Forest Biodiversity in Protected Walnut-Fruit Forests in Kyrgyzstan
We used a spatially explicit model of forest dynamics, supported by empirical field data and socioeconomic data, to examine the impacts of human disturbances on a protected forest landscape in Kyrgyzstan. Local use of 27 fruit and nut species was recorded and modeled. Results indicated that in the presence of fuelwood cutting with or without grazing, species of high socioeconomic impor- tance such as Juglans regia, Malus spp., and Armeniaca vulgaris were largely eliminated from the landscape after 50â150 yr. In the absence of disturbance or in the presence of grazing only, decline of these species occurred at a much lower rate, owing to competi- tive interactions between tree species. This suggests that the current intensity of fuelwood harvesting is not sustainable. Conversely, cur- rent grazing intensities were found to have relatively little impact on forest structure and composition, and could potentially play a positive role in supporting regeneration of tree species. These results indicate that both positive and negative impacts on biodiversity can arise from human populations living within a protected area. Potentially, these could be reconciled through the development of participatory approaches to conservation management within this reserve, to ensure the maintenance of its high conservation value while meeting human needs
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