896 resultados para Sperm Viability


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The role played by the Big Three credit rating agencies (Standard & Poor’s, Moody’s, and Fitch) in the creation of the recent Financial Crisis has been well documented, as too has their conduct in the aftermath of the Crisis where they contributed to the prolonging of the effects of the systemic breakdown. Also, with a string of record fines and cease-and-desist orders in the wake of the Crisis lending weight to the notion that the Big Three have no plans of performing any more ethically, there are a number of organisations that are endeavouring to provide a better alternative to the stranglehold of the Big Three. In the first instalment of the Viability of a Response series we were introduced to the International Non-Profit Credit Rating Agency who, through the amalgamation of forward-looking and non-profit ideals, intends to inject some much needed ethical consideration into the process of providing ratings that are crucial to the marketplace . In this edition of the series, we will be introduced to the Universal Credit Rating Group (UCRG) which is an alliance between Dagong Global Ratings, RusRating, and Egan-Jones Rating Company. We will start by learning more about this alliance that is due to come into effect in the next few years, and then the article will examine the reality of the situation to come to a conclusion on what the Group’s chances of success may be.

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Mycobacteria of the Mycobacterium tuberculosis complex (MTBC) greatly affect humans and animals worldwide. The life cycle of mycobacteria is complex and the mechanisms resulting in pathogen infection and survival in host cells are not fully understood. Recently, comparative genomics analyses have provided new insights into the evolution and adaptation of the MTBC to survive inside the host. However, most of this information has been obtained using M. tuberculosis but not other members of the MTBC such as M. bovis and M. caprae. In this study, the genome of three M. bovis (MB1, MB3, MB4) and one M. caprae (MB2) field isolates with different lesion score, prevalence and host distribution phenotypes were sequenced. Genome sequence information was used for whole-genome and protein-targeted comparative genomics analysis with the aim of finding correlates with phenotypic variation with potential implications for tuberculosis (TB) disease risk assessment and control. At the whole-genome level the results of the first comparative genomics study of field isolates of M. bovis including M. caprae showed that as previously reported for M. tuberculosis, sequential chromosomal nucleotide substitutions were the main driver of the M. bovis genome evolution. The phylogenetic analysis provided a strong support for the M. bovis/M. caprae clade, but supported M. caprae as a separate species. The comparison of the MB1 and MB4 isolates revealed differences in genome sequence, including gene families that are important for bacterial infection and transmission, thus highlighting differences with functional implications between isolates otherwise classified with the same spoligotype. Strategic protein-targeted analysis using the ESX or type VII secretion system, proteins linking stress response with lipid metabolism, host T cell epitopes of mycobacteria, antigens and peptidoglycan assembly protein identified new genetic markers and candidate vaccine antigens that warrant further study to develop tools to evaluate risks for TB disease caused by M. bovis/M.caprae and for TB control in humans and animals.

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Background: Human female orgasm is a vexed question in the field while there is credible evidence of cryptic female choice that has many hallmarks of orgasm in other species. Our initial goal was to produce a proof of concept for allowing females to study an aspect of infertility in a home setting, specifically by aligning the study of human infertility and increased fertility with the study of other mammalian fertility. In the latter case - the realm of oxytocin-mediated sperm retention mechanisms seems to be at work in terms of ultimate function (differential sperm retention) while the proximate function (rapid transport or cervical tenting) remains unresolved. Method: A repeated measures design using an easily taught technique in a natural setting was used. Participants were a small (n=6), non-representative sample of females. The introduction of a sperm-simulant combined with an orgasm-producing technique using a vibrator/home massager and other easily supplied materials. Results: The sperm flowback (simulated) was measured using a technique that can be used in a home setting. There was a significant difference in simulant retention between the orgasm (M=4.08, SD=0.17) and non-orgasm (M=3.30, SD=0.22) conditions; t (5)=7.02, p=0.001. Cohen’s d=3.97, effect size r=0.89. This indicates a medium to small effect size. Conclusions: This method could allow females to test an aspect of sexual response that has been linked to lowered fertility in a home setting with minimal training. It needs to be replicated with a larger sample size.

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The aim of this research are to know the effects of physiological NaCl dilution levels and storage duration on sperm motility and abnormality of  Muscovy duck. Materials which used in this research were semen that collected of 1  - 1,5 years of four Muscovy duck. Semen were treated by physiological NaCl dilution levels nol , three, six and nine and storage duration ( t0 = 0 minute t1 =45minutes and t2=90 minute). Replication was three tapping periode . The method of this research was laboratory experimental with Randomized Complete Blok Design (RBD) in Split Plot Design (SPD)  pattern ,as main plot is Physiological NaCl dilation levels and as sub plot is storage duration. Result of the experiment showed that physiological NaCl dilution levels was very significantly influences on sperm motility (p<0,01) and significantly influences and sperm abnormality (p<0,05) . The storage duration was very significantly influences and sperm motility and abnormality (p<0,01) .Orthogonal duration polynomial assayed showed that the effect of physiological NaCl dilution levels to sperm motility  had a linier regression line with the a equation as Y =69.94 - 2.65 X,  r=0,49 R2=0.24 with Y presented to sperm motility and X represented to physiological NaCl dilution levels  sperm and effect of storage duration to sperm motility had a linier regression line with the equation as Y =74.24-0.35 X, r =0.73 R2=0.53 with Y represented to sperm motility and X represented to storage duration . The effect of physiological NaCl dilution levels to sperm abnormality had a linier regression line with the equation as Y =5.61+0.34X, r=0.52 R2=0.27 with Y represented to sperm to abnormality and X represented to regression line with the equation as Y =6.74+0.01X, r=0.24R2=0.060 with Y represented to sperm abnormality and X represented to storage duration. It is can be concluded that a higher physiological NaCl dilation levels and storage duration caused sperm to motility decreased and sperm abnormality increased. (Animal Production 3(2): 45-52 (2001)Key Word: sperm Muscovy duck.

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AI for cattle has been develop in Indonesia in contrast, AI for small ruminants (sheep and goat) are less developed. Its due to the lack of facilities, processing and packaging during storage. This research aims to compare the effectivity and efficiency of two different packaging technique (test tube and straw). Test tube and 0.25 ml mini straw were tested . Semen was obtained from adult PE buck (3 yr) after collection by using  artificial vagina. The fresh semen was then evaluated and diluted 5 folds with 2.9 percent Na-citrate. Diluted semen then packed in test tube and mini straw, and stored in refrigerator (100C) for 7 days. Observations were done everyday on sperm motility, abnormality and percentage of  live sperm. Observation were made at 370C. Observation on fresh ejaculate showed that semen has 6x 109/ml concentration, 90 percent motility, 8 percent abnormality and  95 percent  live sperm. Five folds dilution reduced sperm concentration to 1.2 x 109/ml, but did not change sperm motility, abnormality and percent of live sperm. Sperm was then packed according  to the treatments. Storage in both packaging did significantly reduce  (P<0.01) sperm motility and percent live sperm, but not for sperm abnormality. All sperm stored in test tube were classified death at day 5 storage. However, sperm in the straw were remain live eventhough the percentages was low. It can be concluded that straw has a better result than test tube. Eventhough sperm motility was extremely low, it remains valuable for cervical insemination. (Animal Production 1(1) : 24-29 (1999).  Key Words : Sperm, PE Buck, Straw, Test Tube

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The research entitled “The Effect of Level Testosterone Addition in Diluents and Level Dilution on Speed Movement and Abnormality of Kedu Chicken Sperm” was conducted in Laboratory of Physiology and Reproduction, Faculty of Animal Science, UNSOED, started at August 15th to September 15th , 2001. The aims of  this research were to obtain influences of level testosterone and dilution on speed movement and secondary abnormality kedu chicken sperm and obtain interaction between the treatments. The tapped sperm from nine kedu chickens were used in this research. This Experiment was performed 4 x 3 Factorials with Randomized  Completely Block Design (RCBD) as the basic design. The treatment combinations were level testosterone 0, 300, 600 and 900 μg (t0, t1, t2 and t3) and level of dilution 4, 6 and 8 time (in a row p1, p2 and p3). The tapping period was replicated four times as a group (replicated) with two days interval. The result of this research showed that the interaction between level of testosterone addition and level of dilution gave a non-significant effect to speed movement sperm but significant to abnormality of kedu chicken sperm. The group gave a significant influence (P<0.05) to speed movement sperm and non significant to sperm abnormality. The interaction of level testosterone addition and level dilution of kedu chicken semen (T x P) has a quadratic regression to sperm abnormality with regression comparison is Y = 24.418 – 0.014 X +1.187E – 05 X², with peak point is (543.76: 20.23) of correlation coefficient (r) 0.55 and determination coefficient (R²) as 30.34%. The addition of 600 μg testosterone level with 6 level dilutions was the best to defend sperm abnormality. (Animal Production 4(2): 60-70 (2002) Key Words : Spermatozoa, Kedu Chicken, Testosterone, Dilution, Speed Movement and Abnormality

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The history of the settlement of the province is tied to patterns of exploration and min development. In Northern British Columbia the Cariboo goldfields provided the impetus for settlement of the region and the beginning for mining to extend into the watern and northern regions in a series of minor gold rushes. The northern half of the province has a geological diverse mineral base that supports a wide variety of mining, and a gradual improvement of exploration and mining methods due to scientific knowledge and technology provided opportunities for lode gold and base metal mines to be developed. The success of mining is based on world ore prices and competitive markets that impact the economic viability of developing a mine. Mining faces increasing pressures in the northern half of the province due to other resource values, such as tourism or protected areas, that claim and compete for a similar land base.

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Habitat fragmentation can have an impact on a wide variety of biological processes including abundance, life history strategies, mating system, inbreeding and genetic diversity levels of individual species. Although fragmented populations have received much attention, ecological and genetic responses of species to fragmentation have still not been fully resolved. The current study investigated the ecological factors that may influence the demographic and genetic structure of the giant white-tailed rat (Uromys caudimaculatus) within fragmented tropical rainforests. It is the first study to examine relationships between food resources, vegetation attributes and Uromys demography in a quantitative manner. Giant white-tailed rat densities were strongly correlated with specific suites of food resources rather than forest structure or other factors linked to fragmentation (i.e. fragment size). Several demographic parameters including the density of resident adults and juvenile recruitment showed similar patterns. Although data were limited, high quality food resources appear to initiate breeding in female Uromys. Where data were sufficient, influx of juveniles was significantly related to the density of high quality food resources that had fallen in the previous three months. Thus, availability of high quality food resources appear to be more important than either vegetation structure or fragment size in influencing giant white-tailed rat demography. These results support the suggestion that a species’ response to fragmentation can be related to their specific habitat requirements and can vary in response to local ecological conditions. In contrast to demographic data, genetic data revealed a significant negative effect of habitat fragmentation on genetic diversity and effective population size in U. caudimaculatus. All three fragments showed lower levels of allelic richness, number of private alleles and expected heterozygosity compared with the unfragmented continuous rainforest site. Populations at all sites were significantly differentiated, suggesting restricted among population gene flow. The combined effects of reduced genetic diversity, lower effective population size and restricted gene flow suggest that long-term viability of small fragmented populations may be at risk, unless effective management is employed in the future. A diverse range of genetic reproductive behaviours and sex-biased dispersal patterns were evident within U. caudimaculatus populations. Genetic paternity analyses revealed that the major mating system in U. caudimaculatus appeared to be polygyny at sites P1, P3 and C1. Evidence of genetic monogamy, however, was also found in the three fragmented sites, and was the dominant mating system in the remaining low density, small fragment (P2). High variability in reproductive skew and reproductive success was also found but was less pronounced when only resident Uromys were considered. Male body condition predicted which males sired offspring, however, neither body condition nor heterozygosity levels were accurate predictors of the number of offspring assigned to individual males or females. Genetic spatial autocorrelation analyses provided evidence for increased philopatry among females at site P1, but increased philopatry among males at site P3. This suggests that male-biased dispersal occurs at site P1 and female-biased dispersal at site P3, implying that in addition to mating systems, Uromys may also be able to adjust their dispersal behaviour to suit local ecological conditions. This study highlights the importance of examining the mechanisms that underlie population-level responses to habitat fragmentation using a combined ecological and genetic approach. The ecological data suggested that habitat quality (i.e. high quality food resources) rather than habitat quantity (i.e. fragment size) was relatively more important in influencing giant white-tailed rat demographics, at least for the populations studied here . Conversely, genetic data showed strong evidence that Uromys populations were affected adversely by habitat fragmentation and that management of isolated populations may be required for long-term viability of populations within isolated rainforest fragments.

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For the last two decades heart disease has been the highest single cause of death for the human population. With an alarming number of patients requiring heart transplant, and donations not able to satisfy the demand, treatment looks to mechanical alternatives. Rotary Ventricular Assist Devices, VADs, are miniature pumps which can be implanted alongside the heart to assist its pumping function. These constant flow devices are smaller, more efficient and promise a longer operational life than more traditional pulsatile VADs. The development of rotary VADs has focused on single pumps assisting the left ventricle only to supply blood for the body. In many patients however, failure of both ventricles demands that an additional pulsatile device be used to support the failing right ventricle. This condition renders them hospital bound while they wait for an unlikely heart donation. Reported attempts to use two rotary pumps to support both ventricles concurrently have warned of inherent haemodynamic instability. Poor balancing of the pumps’ flow rates quickly leads to vascular congestion increasing the risk of oedema and ventricular ‘suckdown’ occluding the inlet to the pump. This thesis introduces a novel Bi-Ventricular Assist Device (BiVAD) configuration where the pump outputs are passively balanced by vascular pressure. The BiVAD consists of two rotary pumps straddling the mechanical passive controller. Fluctuations in vascular pressure induce small deflections within both pumps adjusting their outputs allowing them to maintain arterial pressure. To optimise the passive controller’s interaction with the circulation, the controller’s dynamic response is optimised with a spring, mass, damper arrangement. This two part study presents a comprehensive assessment of the prototype’s ‘viability’ as a support device. Its ‘viability’ was considered based on its sensitivity to pathogenic haemodynamics and the ability of the passive response to maintain healthy circulation. The first part of the study is an experimental investigation where a prototype device was designed and built, and then tested in a pulsatile mock circulation loop. The BiVAD was subjected to a range of haemodynamic imbalances as well as a dynamic analysis to assess the functionality of the mechanical damper. The second part introduces the development of a numerical program to simulate human circulation supported by the passively controlled BiVAD. Both investigations showed that the prototype was able to mimic the native baroreceptor response. Simulating hypertension, poor flow balancing and subsequent ventricular failure during BiVAD support allowed the passive controller’s response to be assessed. Triggered by the resulting pressure imbalance, the controller responded by passively adjusting the VAD outputs in order to maintain healthy arterial pressures. This baroreceptor-like response demonstrated the inherent stability of the auto regulating BiVAD prototype. Simulating pulmonary hypertension in the more observable numerical model, however, revealed a serious issue with the passive response. The subsequent decrease in venous return into the left heart went unnoticed by the passive controller. Meanwhile the coupled nature of the passive response not only decreased RVAD output to reduce pulmonary arterial pressure, but it also increased LVAD output. Consequently, the LVAD increased fluid evacuation from the left ventricle, LV, and so actually accelerated the onset of LV collapse. It was concluded that despite the inherently stable baroreceptor-like response of the passive controller, its lack of sensitivity to venous return made it unviable in its present configuration. The study revealed a number of other important findings. Perhaps the most significant was that the reduced pulse experienced during constant flow support unbalanced the ratio of effective resistances of both vascular circuits. Even during steady rotary support therefore, the resulting ventricle volume imbalance increased the likelihood of suckdown. Additionally, mechanical damping of the passive controller’s response successfully filtered out pressure fluctuations from residual ventricular function. Finally, the importance of recognising inertial contributions to blood flow in the atria and ventricles in a numerical simulation were highlighted. This thesis documents the first attempt to create a fully auto regulated rotary cardiac assist device. Initial results encourage development of an inlet configuration sensitive to low flow such as collapsible inlet cannulae. Combining this with the existing baroreceptor-like response of the passive controller will render a highly stable passively controlled BiVAD configuration. The prototype controller’s passive interaction with the vasculature is a significant step towards a highly stable new generation of artificial heart.

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The road and transport industry in Australia and overseas has come a long way to understanding the impact of road traffic noise on the urban environment. Most road authorities now have guidelines to help assess and manage the impact of road traffic noise on noise-sensitive areas and development. While several economic studies across Australia and overseas have tried to value the impact of noise on property prices, decision-makers investing in road traffic noise management strategies have relatively limited historic data and case studies to go on. The perceived success of a noise management strategy currently relies largely on community expectations at a given time, and is not necessarily based on the analysis of the costs and benefits, or the long-term viability and value to the community of the proposed treatment options. With changing trends in urban design, it is essential that the 'whole-of-life' costs and benefits of noise ameliorative treatment options and strategies be identified and made available for decisionmakers in future investment considerations. For this reason, CRC for Construction Innovation Australia funded a research project, Noise Management in Urban Environments to help decision-makers with future road traffic noise management investment decisions. RMIT University and the Queensland Department of Main Roads (QDMR) have conducted the research work, in collaboration with the Queensland Department of Public Works, ARUP Pty Ltd, and the Queensland University of Technology. The research has formed the basis for the development of a decision-support software tool, and helped collate technical and costing data for known noise amelioration treatment options. We intend that the decision support software tool (DST) should help an investment decision-maker to be better informed of suitable noise ameliorative treatment options on a project-by-project basis and identify likely costs and benefits associated with each of those options. This handbook has been prepared as a procedural guide for conducting a comparative assessment of noise ameliorative options. The handbook outlines the methodology and assumptions adopted in the decision-support framework for the investment decision-maker and user of the DST. The DST has been developed to provide an integrated user-friendly interface between road traffic noise modelling software, the relevant assessment criteria and the options analysis process. A user guide for the DST is incorporated in this handbook.

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Application of cell-–biomaterial systems in regenerative medicine can be facilitated by their successful low temperature preservation. Vitrification, which avoids ice crystal formation by amorphous solidification, is an emerging approach to cryopreservation. Developing vitrification strategy, effective cryopreservation of alginate–fibrin beads with porcine mesenchymal stromal cells has been achieved in this study. The cell–biomaterial constructs were pre-cultured for 20 days before cryopreservation, allowing for cell proliferation and construct stabilization. Ethylene glycol (EG) was employed as the basic cryoprotectant for two equilibration solutions. Successful cryopreservation of the constructs was achieved using vitrification solution composed of penetrating (EG MW 62 Da) and non-penetrating (sucrose MW 342 Da) cryoprotectants. Stepwise procedure of introduction to and removal of cryoprotectants was brief; direct plunging into liquid nitrogen was applied. Cell viability, evaluated by combining live/death staining and confocal laser microscopy, was similar for both control and vitrified cells in the beads. No detectable damage of microstructure of cryopreserved beads was found as shown by scanning electron microscopy. Both osteogenically induced control and vitrified cells in the constructs were equally capable of mineral production and deposition. There was no statistically significant difference in metabolic activity and proliferation between both groups during the entire culture period. Our study leads to the conclusion that the developed cryopreservation protocol allowed to maintain the integrity of the beads while preserving the ability of the pig bone marrow derived mesenchymal stromal cells to proliferate and subsequently differentiate; demonstrating that vitrification is a promising approach for cryopreser-vation of “ready-to-use” cell–biomaterial constructs.