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101.
Joint Working Group on Veterinary Care Voipio HM Baneux P Gomez de Segura IA Hau J Wolfensohn S 《Laboratory animals》2008,42(1):1-11
Veterinary professionals working in partnership with other competent persons are essential for a successful animal care and use programme. A veterinarian's primary responsibilities are defined by their own professional regulatory bodies, but in this area of work there are further opportunities for contribution, which will assist in safeguarding the health and welfare of animals used in research. These guidelines are aimed not only at veterinarians to explain their duties, and outline the opportunities to improve the health and welfare of animals under their care, but also at employers and regulators to help them meet their responsibilities. They describe the desirability for postgraduate education towards specialization in laboratory animal medicine and detail the many competencies necessary to fulfil the role of the laboratory animal veterinarian. They detail the need for veterinary expertise to promote good health and good welfare of animals used in biomedical research during husbandry as well as when under experimental procedures. Regulatory and ethical aspects are covered as are the involvement of the veterinarian in education and training of others working in the animal care and use programme. Managerial aspects, including occupational health and safety, are also areas where the veterinarian's input can assist in the successful implementation of the programme. 相似文献
102.
BACKGROUND: This study investigated causes of malaria and how cases were managed at household level, in order to improve the ability to identify malaria and ensure correct use of chloroquine. It was conducted in Nakonde District, Northern Province of Zambia, between 2000 and 2001. Nakonde district is in a hyperendemic malaria province, where Plasmodium falciparum is predominant. The district has a total population of 153, 548 people, the majority of whom are peasant farmers. The main aim of the post intervention survey was to establish the proportion of caretakers of children five years and below, who were able to identify simple and severe malaria and treat it correctly using chloroquine in the home. METHODS: A baseline survey was conducted in five wards divided into intervention and control.Intervention and control wards were compared. Village health motivators and vendors were identified and trained in three intervention wards, as a channel through which information on correct chloroquine dose could be transmitted. A total of 575 carers, who were 15 years old and above and had a child who had suffered from malaria 14 days before the survey commenced, were interviewed. The two control wards received no intervention. 345 caretakers were from the intervention wards, while 230 came from the control wards. Identification of malaria and correct use of anti-malarial drugs was assessed in terms of household diagnosis of malaria in children under five years, type and dose of anti-malarial drugs used, self medication and the source of these anti-malarials. RESULTS: The majority of respondents in the study were females (81%). Chloroquine was the most frequently used anti-malarial (48.5%) in both the intervention and control wards. There was no difference between the intervention and control wards at pre-intervention (P = 0.266 and P = 0.956), in the way mothers and other caretakers identified simple and severe malaria. At baseline, knowledge on correct chloroquine dosage in the under five children was comparable between intervention and control wards. Post-intervention revealed that mothers and other caretakers were 32% and 51%, respectively, more likely to identify simple and severe malaria. There was a 60% increase on correct chloroquine dosage in all age groups among carers living in post-intervention wards. CONCLUSION: Compliance with standard therapeutic doses and correct identification of malaria was poorest in control wards, where no motivators and vendors were trained. 相似文献
103.
López-Valenzuela BE Armenta-Bojórquez AD Hernández-Verdugo S Apodaca- Sánchez MA Samaniego-Gaxiola JA Valdez-Ortiz A 《Phyton》2019,88(1):37-46
Microbes that are beneficial to plants are used to
enhance the crop growth, yield and are alternatives to chemical
fertilizers. Trichoderma and Bacillus are the predominant plant
growth-promoting fungi and bacteria. The objective of this study
was select, characterize, and evaluate isolates of Trichoderma
spp. and Bacillus spp. native from the northern region of Sinaloa,
Mexico, and assess their effect on growth promotion in maize (Zea
mays L.). In greenhouse conditions, four Trichoderma isolates and
twenty Bacillus isolates, as well as two controls, were tested in a
completely randomized design with three replicates. We selected
the two best strains of Trichoderma and Bacillus: TB = Trichoderma
asperellum, TF = Trichoderma virens, B14 = Bacillus cereus sensu
lato and B17 = Bacillus cereus, which were evaluated in the field in
a completely randomized blocks in factorial arrangement design
with three replicates applying different rates of nitrogen fertilizer
(0, 150 kg N/ha, and 300 kg N/ha). Treatments 5 (B17 = B. cereus)
and 11 (TF = T. virens) both fertilized with 150 kg N/ha showed
similar yields and they did not reveal significant differences from
the treatments fertilized with 300 kg N/ha. This indicated that
treatment 5 (B17= B. cereus with 150 kg N/ha) and treatment
11 (TF= T. virens with 150 kg N/ha) were efficient as growth
promoters, by not showing significant differences in root volume
and dry weight of foliage. The results indicated a reduction of 50%
in the rate of nitrogen to fertilizer required for maize (Zea mays
L.) crops. These microorganisms Trichoderma and Bacillus could
be an alternative to reduce the use of chemical fertilizers in maize. 相似文献
104.
T.J. Spencer L.A. Hidalgo‐Bastida S.H. Cartmell I. Halliday C.M. Care 《Biotechnology and bioengineering》2013,110(4):1221-1230
Computer simulations can potentially be used to design, predict, and inform properties for tissue engineering perfusion bioreactors. In this work, we investigate the flow properties that result from a particular poly‐L ‐lactide porous scaffold and a particular choice of perfusion bioreactor vessel design used in bone tissue engineering. We also propose a model to investigate the dynamic seeding properties such as the homogeneity (or lack of) of the cellular distribution within the scaffold of the perfusion bioreactor: a pre‐requisite for the subsequent successful uniform growth of a viable bone tissue engineered construct. Flows inside geometrically complex scaffolds have been investigated previously and results shown at these pore scales. Here, it is our aim to show accurately that through the use of modern high performance computers that the bioreactor device scale that encloses a scaffold can affect the flows and stresses within the pores throughout the scaffold which has implications for bioreactor design, control, and use. Central to this work is that the boundary conditions are derived from micro computed tomography scans of both a device chamber and scaffold in order to avoid generalizations and uncertainties. Dynamic seeding methods have also been shown to provide certain advantages over static seeding methods. We propose here a novel coupled model for dynamic seeding accounting for flow, species mass transport and cell advection‐diffusion‐attachment tuned for bone tissue engineering. The model highlights the timescale differences between different species suggesting that traditional homogeneous porous flow models of transport must be applied with caution to perfusion bioreactors. Our in silico data illustrate the extent to which these experiments have the potential to contribute to future design and development of large‐scale bioreactors. Biotechnol. Bioeng. 2013; 110: 1221–1230. © 2012 Wiley Periodicals, Inc. 相似文献
105.
106.
Giorgio Tamburlini Klara Yadgarova Asamidin Kamilov Alberta Bacci for the The Maternal Neonatal Care Quality Improvement Working Group 《PloS one》2013,8(10)
Background
Gaps in quality of care are seriously affecting maternal and neonatal health globally but reports of successful quality improvement cycles implemented at large scale are scanty. We report the results of a nation-wide program to improve quality of maternal and neonatal hospital care in a lower-middle income country focusing on the role played by standard-based participatory assessments.Methods
Improvements in the quality of maternal and neonatal care following an action-oriented participatory assessment of 19 areas covering the whole continuum from admission to discharge were measured after an average period of 10 months in four busy referral maternity hospitals in Uzbekistan. Information was collected by a multidisciplinary national team with international supervision through visit to hospital services, examination of medical records, direct observation of cases and interviews with staff and mothers. Scores (range 0 to 3) attributed to over 400 items and combined in average scores for each area were compared with the baseline assessment.Results
Between the first and the second assessment, all four hospitals improved their overall score by an average 0.7 points out of 3 (range 0.4 to 1), i.e. by 22%. The improvements occurred in all main areas of care and were greater in the care of normal labor and delivery (+0.9), monitoring, infection control and mother and baby friendly care (+0.8) the role of the participatory action-oriented approach in determining the observed changes was estimated crucial in 6 out of 19 areas and contributory in other 8. Ongoing implementation of referral system and new classification of neonatal deaths impede the improved process of care to be reflected in current statistics.Conclusions
Important improvements in the quality of hospital care provided to mothers and newborn babies can be achieved through a standard-based action-oriented and participatory assessment and reassessment process. 相似文献107.
108.
A cyclic polymeric liquid crystal system is simulated using the Metropolis Monte Carlo method in the NVT ensemble. The polymeric system consists of mesogenic moieties attached by alkyl chain spacers to siloxane ring polymers. In the model, the mesogenic moieties are represented individually by an anisotropic Lennard-Jones potential and the polymer ring is represented solely as a constraint on the relative motions of the attached mesogens. A transition from calamitic ordering to discotic ordering is observed as the ring-mesogen bond is varied from full flexible to rigid. 相似文献
109.
Several genes that restrict nodulation with specific Bradyrhizobiumstrains are known in Glycine max (soybean), and a similar system of nodulation restriction has recently been discovered in the related North American legume Amphicarpaea bracteata. We analyzed how nodulation-restrictive genotypes of each plant interacted with Bradyrhizobium strains sampled from the other host species. Ten bacterial isolates from A. bracteata that nodulated differentially with genotypes of their homologous host legume showed uniform responses to two soybean isogenic lines that differed at the Rj4 locus controlling nodulation restriction: all isolates formed nodules of normal size and morphology on both isolines. However, little or no nitrogen fixation occurred in any of these symbioses. A. bracteata genotypes that displayed broad vs. restricted symbiotic phenotypes toward naturally-associated bradyrhizobia were also tested with two bacterial isolates from soybean (USDA 76 and USDA 123). Both isolates formed nodules and fixed nitrogen in association with both A. bracteata genotypes. However, symbiotic effectiveness (as measured by acetylene reduction assays) was normal only for the combination of USDA 76 with the restrictive A. bracteata genotype. Overall, these results indicate that plant genes that restrict nodulation by certain naturally-associated bradyrhizobia do not confer comparable specificity when plants interact with bacteria from another related legume species. 相似文献
110.
Daphnée Lamarche Jennie Johnstone Nicole Zytaruk France Clarke Lori Hand Dessi Loukov Jake C. Szamosi Laura Rossi Louis P. Schenck Chris P. Verschoor Ellen McDonald Maureen O. Meade John C. Marshall Dawn M. E. Bowdish Tim Karachi Diane Heels-Ansdell Deborah J. Cook Michael G. Surette for the PROSPECT Investigators Canadian Critical Care Trials Group Canadian Critical Care Translational Biology Group 《Respiratory research》2018,19(1):245