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1.
This article considers the experiences of a Samoan female geographer undertaking community‐based field research in her home country, and identifies some lessons for researchers working in similar circumstances. The paper suggests that ethical behaviour in research is ‘place‐specific’, and there is therefore a need to employ culturally sensitive and ‘location‐specific’ methodologies when undertaking community‐based research fieldwork. For the lead researcher, growing up in Samoa played a significant role in gaining an understanding of a set of robust and effective procedures to evaluate citizens' resilience to climatic and other environmental challenges. Fluency in everyday and more formal local languages, and awareness of local differences, each with multi‐layered connections to local communities, understanding cultural nuances and practising respect for va tapuia [sacred space or relationships] protocols, together facilitated the process of knowledge acquisition and helped to confirm the validity of the conclusions derived from the study.  相似文献   
2.
Ultrasonography of the cisterna chyli has been used in humans to diagnose increased lymphatic flow or lymph flow obstruction and to guide percutaneous embolization of the thoracic duct via the cisterna chyli. The aim of this study was to describe the ultrasonographic characteristics of the dorsal portion of cisterna chyli in dogs and cats with chylous ascites or chylothorax and in a group of healthy dogs and cats. The aorta and the cranial mesenteric artery were used as anatomic landmarks. Ultrasonography was performed before and 2 h after a fatty meal in healthy dogs and cats. The visualized structure was confirmed to be a dilated cisterna chyli at necropsy in a dog with chylous ascites. The confirmed or presumed cisterna chyli was consistently detected using ultrasonography in nonfasted healthy animals and clinically affected animals and appeared as an anechoic tubular structure, without detectable flow, at the right dorsolateral aspect of the aorta. It had a similar ultrasonographic appearance in patients with chyloabdomen and in nonfasted healthy dogs and cats. There was considerable overlap in diameters of the cisterna chyli for affected and healthy animals. The shape and size of the cisterna chyli in an individual animal were variable during the same ultrasound examination and between different examinations. This study demonstrated the appearance of the presumed dorsal portion of the cisterna chyli by ultrasonography and might provide useful preliminary data for further studies into the feasibility of ultrasound‐guided injections or aspirations of the cisterna chyli in dogs and cats.  相似文献   
3.
Camels are the most valuable livestock species in the Horn of Africa and play a pivotal role in the nutritional sustainability for millions of people. Their health status is therefore of utmost importance for the people living in this region. Streptococcus agalactiae, a Group B Streptococcus (GBS), is an important camel pathogen. Here we present the first epidemiological study based on genetic and phenotypic data from African camel derived GBS. Ninety-two GBS were characterized using multilocus sequence typing (MLST), capsular polysaccharide typing and in vitro antimicrobial susceptibility testing. We analysed the GBS using Bayesian linkage, phylogenetic and minimum spanning tree analyses and compared them with human GBS from East Africa in order to investigate the level of genetic exchange between GBS populations in the region. Camel GBS sequence types (STs) were distinct from other STs reported so far. We mapped specific STs and capsular types to major disease complexes caused by GBS. Widespread resistance (34%) to tetracycline was associated with acquisition of the tetM gene that is carried on a Tn916-like element, and observed primarily among GBS isolated from mastitis. The presence of tetM within different MLST clades suggests acquisition on multiple occasions. Wound infections and mastitis in camels associated with GBS are widespread and should ideally be treated with antimicrobials other than tetracycline in East Africa.  相似文献   
4.
This study on primiparous sows was designed to 1) determine the impact of nursing a large litter on LH secretion and follicular development, and 2) investigate the metabolic adaptations by which milk yield increases with litter size. At farrowing, crossbred, primiparous sows were assigned to 1 of 3 experimental groups differing in litter size and feed allowance. Sows with 13 or 14 piglets (13AL, n = 7) were fed ad libitum. Sows with 7 piglets were fed ad libitum (7AL, n = 6) or were feed-restricted (7R, n = 8). The restriction was based on the estimated energy deficiency for the 13AL sows. On d 9 +/- 1 of lactation, a jugular catheter was surgically implanted. Serial blood samplings and glucose tolerance tests were performed in mid- and late lactation. Sows were slaughtered 3 d after weaning, and ovarian characteristics were recorded. During lactation, the 7AL sows lost no or little body reserves, and their estimated energy balance was near zero. The 13AL and 7R sows exhibited similar negative energy balances and similar losses of backfat and estimated lipid content. Litter growth rate was greater (P < 0.05) in the 13AL than in the 7AL and 7R groups. After weaning, the volume of the largest 14 follicles was smaller (P < 0.05) in sows nursing 13 or 14 piglets than in sows with 7 piglets. Plasma concentrations of LH and LH pulse frequency did not differ between groups (P > 0.1). The longer glucose half-life on d 16 than on d 27 of lactation (22.5 vs. 18.8 min; P < 0.05) indicated a lower glucose tolerance in mid- than in late lactation. The area under the insulin curve was greater in the 7AL than in the 13AL sows (P = 0.08) and intermediate in the 7R group, with no differences in glucose profiles. This led to the suggestion that the 7AL sows were more resistant to insulin than the 13AL sows. In all groups of sows, follicular development after weaning was correlated with LH secretion in midlactation. Active follicular development was associated with prolonged secretion of insulin in response to glucose challenge. Our results show that besides litter size, a sow's metabolic status in lactation influences follicular maturation after weaning and also indicate that the metabolic adaptations by which primiparous sows nursing large litters increase litter growth rate and body reserve mobilization do not involve an accentuated peripheral insulin resistance.  相似文献   
5.
Equine coital exanthema (ECE) is an acute, venereal disease caused by equid herpesvirus 3 (EHV-3), characterized by the formation of papules, vesicles, pustules, and ulcers on the vaginal and vestibular mucosa as well as on the skin of the penis, prepuce, and perineal region of mares and stallions. The present work describes an outbreak of ECE characterized by typical lesions around the anus and on the perineal skin, discomfort, and anorectal lymphadenopathy, which occurred in a large number of donor and recipient mares at an embryo transfer center in Argentina. We found that the horses' movement pattern, the environmental conditions, and the management procedures could have favored the introduction and/or reactivation from latency and spread of EHV-3. Although this is the first report of an outbreak of ECE in an embryo transfer facility, it reinforces the need to introduce additional hygienic and preventive measures to avoid EHV-3 spread and future ECE outbreaks.  相似文献   
6.
  • ? Two decades after the launching of the monitoring program of forest ecosystems in Europe (ICP forests), a unique data set is now available regarding the foliar nutritional status of the main broad-leaved species growing in much-diversified sites (soil, climate).
  • ? This study focuses on the foliar concentration time series (1993 to 2005) of the French (RENECOFOR), Walloon and Luxemburg broad-leaved plots. The aim is to show long-term trends while taking the inter-plot and inter-annual variability into account.
  • ? Two kinds of statistical processing were used to analyze the data on foliar chemistry: principal component analysis (PCAs) and linear mixed models. In general, the main temporal trends reveal a decrease in the foliar P concentration and a decrease in the foliar Ca concentration, except for European beech on acid soils.
  • ? These temporal patterns confirm the trends previously observed and could be explained by the joint actions of several processes that influence tree nutrition in the long term: tree age, N and S deposition, harvesting and climate.
  •   相似文献   
    7.
    European gorse (Ulex europaeus L.) N2 fixation rate (%Ndfa) was studied in a maritime pine (Pinus pinaster Aït.) oligotrophic forest. Fertilization field trials were carried out on 5 sites with various inputs of phosphorus (0–240 kg P2O5·ha?1). Seven to ten years after pine planting, gorse were sampled to evaluate the effect of P fertilization on gorse %Ndfa, determined using the 15N natural abundance method. One of the prerequisites of this method is the existence of a significant difference between the 15N/14N ratios in the atmospheric N reference and in the stand soil N references. This prerequisite was satisfied for 80 of 120 cases. The average %Ndfa was high (70 ± 3%) but with high local variability. No significant difference in %Ndfa was detected among P treatments. Nitrogen concentration of gorse was significantly higher in the highest dose treatments compared to the control.  相似文献   
    8.
    A physical map of the 1-gigabase bread wheat chromosome 3B   总被引:2,自引:0,他引:2  
    As the staple food for 35% of the world's population, wheat is one of the most important crop species. To date, sequence-based tools to accelerate wheat improvement are lacking. As part of the international effort to sequence the 17-billion-base-pair hexaploid bread wheat genome (2n = 6x = 42 chromosomes), we constructed a bacterial artificial chromosome (BAC)-based integrated physical map of the largest chromosome, 3B, that alone is 995 megabases. A chromosome-specific BAC library was used to assemble 82% of the chromosome into 1036 contigs that were anchored with 1443 molecular markers, providing a major resource for genetic and genomic studies. This physical map establishes a template for the remaining wheat chromosomes and demonstrates the feasibility of constructing physical maps in large, complex, polyploid genomes with a chromosome-based approach.  相似文献   
    9.
    10.
    This study was conducted to determine whether young calves with maternal antibodies against bovine herpesvirus type 1 (BHV-1) but without antibodies against glycoprotein E (gE) can produce an active antibody response to gE after a BHV-1 infection. Five calves received at birth colostrum from gE-seronegative cows which had been vaccinated two or three times with an inactivated BHV-1, gE-deleted marker vaccine. After inoculation with a wild-type virulent strain of BHV-1, all the passively immunised gE-negative calves shed virus in large amounts in their nasal secretions. All the calves seroconverted to gE within two to four weeks after inoculation and then had high levels of gE antibodies for at least four months. The development of an active cell-mediated immune response was also detected by in vitro BHV-1-specific interferon-gamma assays. All the calves were latently infected, because one of them re-excreted the virus spontaneously and the other four did so after being treated with dexamethasone. The results showed that under the conditions of this work the gE-negative marker could also distinguish between passively immunised and latently infected calves.  相似文献   
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