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11.
OBJECTIVE: To assess iodine status and its determinants in women of childbearing age in a rural area in the Kayes region, Mali, West Africa. DESIGN: Cross-sectional study where women's iodine status was indicated by urinary iodine concentration (UIC) and level of goitre based on palpation. Salt iodine was assessed semi-quantitatively at household level. Individual characteristics were collected using questionnaires. SETTING: Fifteen villages in a rural area in the Kayes region of Mali. SUBJECTS: Women aged 15-45 years (n=423). RESULTS: Median UIC was 2.7 microg dl(-1), and only 6% of the women had adequate iodine status of UIC >10 microg dl(-1). Most women (60%) had visible goitre, and only 9% were classified as without goitre. Only 39% of the households were using salt with any iodine, and level of knowledge about salt iodisation was low. Main determinants of UIC were breast-feeding and level of salt iodisation; currently breast-feeding women had lower UIC, and UIC increased with increasing level of iodine in household salt. Prevalence of goitre was lower in older women with higher body mass index. CONCLUSION: The study indicates severe iodine deficiency in the study area. Urgent action is needed to improve the situation through enforcing salt iodisation legislation and increasing the level of knowledge about the importance of iodised salt in the population. 相似文献
12.
Recent findings on the causes of Atlantic salmon embryo mortality during winter in a hydropeaking river suggest that long duration drawdowns during very cold periods are the most likely cause of mortality in the ramping zone. This paper presents a framework in which thresholds for optimal embryo survival at the microscale are linked to physical habitat requirements at the mesoscale and integrated into alternative hydropower operations at the catchment scale. The connections within this framework are derived from a one‐dimensional hydraulic model at the mesoscale and a hydropower simulation programme at the catchment scale. The economic costs and feasibility of several alternative options for hydropeaking operation that would comply with ecological requirements for optimal survival of embryos were evaluated. A method to assess a wide range of alternative hydropower options that considers key factors to mitigate the conflicting requirements of ecological targets, technical feasibility and economics is presented. Targeted alternative environmental flow releases to meet specific ecological objectives are often more effective than general operational rules to comply with legislation. The development of well‐informed and targeted mitigation strategies is important for future environmental hydropower management. 相似文献
13.
Linda?Meyer-VeltrupEmail authorView author&#;s OrcID profile Christian?Brischke Gry?Alfredsen Miha?Humar Per-Otto?Fl?te Tord?Isaksson Pia?Larsson?Brelid Mats?Westin J?ran?Jermer 《Wood Science and Technology》2017,51(3):615-637
Comprehensive approaches to predict performance of wood products are requested by international standards, and the first attempts have been made in the frame of European research projects. However, there is still an imminent need for a methodology to implement the durability and moisture performance of wood in an engineering design method and performance classification system. The aim of this study was therefore to establish an approach to predict service life of wood above ground taking into account the combined effect of wetting ability and durability data. A comprehensive data set was obtained from laboratory durability tests and still ongoing field trials in Norway, Germany and Sweden. In addition, four different wetting ability tests were performed with the same material. Based on a dose–response concept, decay rates for specimens exposed above ground were predicted implementing various indicating factors. A model was developed and optimised taking into account the resistance of wood against soft, white and brown rot as well as relevant types of water uptake and release. Decay rates from above-ground field tests at different test sites in Norway were predicted with the model. In a second step, the model was validated using data from laboratory and field tests performed in Germany and Sweden. The model was found to be fairly reliable, and it has the advantage to get implemented into existing engineering design guidelines. The approach at hand might furthermore be used for implementing wetting ability data into performance classification as requested by European standardisation bodies. 相似文献
14.
Gallibacterium anatis, a member of the Pasteurellaceae family, constitute a part of the normal micro-flora of the upper respiratory tract and the lower genital tract in chickens. However, increasing evidence indicate that G. anatis is also associated with a wide range of pathological changes, particularly in the reproductive organs, which leads to decreased egg production, lowered animal welfare and increased mortality. As a recently defined opportunistic pathogen limited focus has been placed on the pathogenesis and putative virulence factors permitting G. anatis to cause disease. One of the most studied virulence determinants is a large RTX-like toxin (GtxA), which has been demonstrated to induce a strong leukotoxic effect on avian macrophages. A number of fimbria of different sizes and shapes has been described. Particularly fimbriae belonging to the F17-like family appears to be common in a diverse selection of G. anatis strains. Mutants lacking the FlfA fimbria were severely attenuated in experimentally infected chickens. Additional characteristics including the ability to express capsular material possibly involved in serum resistance; secretion of metalloproteases capable of degrading immunoglobulins, and hemagglutinins, which may promote biofilm formation are all factors likely linked to the virulence of G. anatis. A major advantage for the study of how G. anatis interact with its host is the ability to perform biologically relevant experimental infections where natural routes of exposure allows reproduction of lesions observed during spontaneous infections. This review summarizes the current understanding of the G. anatis pathogenesis and discusses the contribution of the established and putative virulence factors described for this bacterium to date. 相似文献
15.
Gry Alfredsen Halvor Solheim Rune Slimestad 《European Journal of Forest Research》2008,127(5):387-393
The inhibitory effect of methanol bark extracts from six deciduous and three coniferous European tree species were bioassayed
against eight fungi from the different damage categories, brown rot, white rot, canker and blue-stain. This is the first report
providing data on the antifungal activity of several Europaen tree species against fungi within these damage categories. Generally
the decay fungi were more inhibited by the bark extracts than the blue-stain fungi, while the lowest inhibition was found
among the cancer fungi. The main pattern found between the fungal groups in relation to the bark extracts in this study is
believed to be caused by the route of ingress. Acer platanoides bark extract proved to be the most efficient bark extract tested, significantly reducing the growth rate of all tested fungi.
Betula pubescens bark extract generally gave the weakest reduction in growth rate. In this study, the conifer bark extracts were in general
more active against the canker and blue stain ascomycete fungi than the deciduous trees extracts. 相似文献
16.
Chian Teng Ong Elizabeth M Ross Gry B Boe-Hansen Conny Turni Ben J Hayes Ala E Tabor 《Journal of animal science》2022,100(1)
Animal metagenomic studies, in which host-associated microbiomes are profiled, are an increasingly important contribution to our understanding of the physiological functions, health and susceptibility to diseases of livestock. One of the major challenges in these studies is host DNA contamination, which limits the sequencing capacity for metagenomic content and reduces the accuracy of metagenomic profiling. This is the first study comparing the effectiveness of different sequencing methods for profiling bovine vaginal metagenomic samples. We compared the new method of Oxford Nanopore Technologies (ONT) adaptive sequencing, which can be used to target or eliminate defined genetic sequences, to standard ONT sequencing, Illumina 16S rDNA amplicon sequencing, and Illumina shotgun sequencing. The efficiency of each method in recovering the metagenomic data and recalling the metagenomic profiles was assessed. ONT adaptive sequencing yielded a higher amount of metagenomic data than the other methods per 1 Gb of sequence data. The increased sequencing efficiency of ONT adaptive sequencing consequently reduced the amount of raw data needed to provide sufficient coverage for the metagenomic samples with high host-to-microbe DNA ratio. Additionally, the long reads generated by ONT adaptive sequencing retained the continuity of read information, which benefited the in-depth annotations for both taxonomical and functional profiles of the metagenome. The different methods resulted in the identification of different taxa. Genera Clostridium, which was identified at low abundances and categorized under Order “Unclassified Clostridiales” when using the 16S rDNA amplicon sequencing method, was identified to be the dominant genera in the sample when sequenced with the three other methods. Additionally, higher numbers of annotated genes were identified with ONT adaptive sequencing, which also produced high coverage on most of the commonly annotated genes. This study illustrates the advantages of ONT adaptive sequencing in improving the amount of metagenomic data derived from microbiome samples with high host-to-microbe DNA ratio and the advantage of long reads in preserving intact information for accurate annotations. 相似文献
17.
Gry Jaeger Hege Kippenes Skogmo ?yvor Kolbj?rnsen Hans J?rgen S?iland Larsen Bjarne Bergsj? Henning S?rum 《Acta veterinaria Scandinavica》2013,55(1):67
In spite of yearly vaccination, outbreaks of canine infectious respiratory disease are periodically seen amongst domestic dogs. These infections compromise host defense mechanisms, and, when combined with other stressful events, allow opportunistic pathogens like Streptococcus equi subsp. zooepidemicus to create serious disease. Early recognition and treatment are tremendously important for a successful outcome in these cases. A polyvalent vaccine was given to 22 racing dogs three days after a competition, followed by two days of rest, and then the dogs were returned to regular training. Coughing was noticed among the dogs four days after immunisation. Three days after this outbreak one of the dogs was unusually silent and was found dead the next morning. Simultaneously two other dogs developed haemorrhagic expectorate, depression and dyspnea and were brought in to the veterinary hospital. Streptococcus equi subsp. zooepidemicus was isolated in pure culture from all three cases. They were treated and rehabilitated successfully, and won a sledge race three months later. This paper discusses the necropsy results, treatment regime, rehabilitation and the chronology of vaccination, stressful events and disease. 相似文献
18.
Moesgaard SG Pedersen LG Teerlink T Häggström J Pedersen HD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(5):712-719
The aim of the study was to compare the effect of 2 angiotensin-converting enzyme (ACE) inhibitors on neurohormonal and circulatory variables in Cavalier King Charles Spaniels (CKCSs) with asymptomatic mitral regurgitation (MR). Ten CKCSs with mild to severe untreated MR were treated with 2 ACE inhibitors, quinapril and enalapril (each at 0.5 mg/kg PO q24h for 7 days), in a double-blind, crossover study with a washout period of 7 days between treatments. Blood samples were drawn and echocardiography was performed on days 0, 7, 14, and 21. Both treatments reduced ACE activity (P < .001) and increased renin activity (P < .001) and atrial natriuretic peptide concentration (P < .005). The ACE inhibitors had no effect on the concentrations of nitrate and nitrite (NOx) or asymmetric dimethylarginine (ADMA). On day 0, a lower NOx concentration (P = .02) was found in samples taken in the clinic as compared to samples taken in the homes of the dogs. Quinapril caused a significant reduction in more variables that reflect the severity of MR (eg, jet size and left ventricular end diastolic diameter) than did enalapril. However, in terms of specific variables, no significant difference was identified between the effects of the 2 treatments on MR. These results suggest that ACE inhibitors do not affect NOx and ADMA concentrations in asymptomatic dogs, but exercise, stress, or some combination may influence NOx concentrations in these dogs. 相似文献
19.
H. A. Urke T. Kristensen J. B. Ulvund J. A. Alfredsen 《Fisheries Management and Ecology》2013,20(6):544-552
Migration timing, speed, survival and effects of environmental parameters on migration, between wild and hatchery produced Atlantic salmon, Salmo salar L., smolts in the River Lærdalselva were studied. Hatchery‐reared (n = 40) and wild pre‐smolts (n = 40) were tagged with acoustic tags, and an array of receivers along the migration route was deployed. In all, 77 and 85% of the fish from the two groups, respectively, were recorded as migrating smolts, that is, predation rate and/or numbers of fish opting to remain in the river were low. Hatchery‐reared smolts showed a migration pattern, speed and migration route similar to wild smolts, even though the time period between river release and onset of migration was relatively short. Both groups of smolt showed high migration speed through both the river and the fjord compared with other studies. 相似文献
20.
Gry Aletta Bjørlykke Bjørn Olav Kvamme Arnt J. Raae Bjorn Roth Erik Slinde 《Fish physiology and biochemistry》2013,39(4):871-879
The different stunning methods for Atlantic salmon can still be improved with regard to animal welfare. Salmon exposed to carbon monoxide expressed no aversive reactions towards CO as such. CO exposed fish showed an earlier onset of rigour mortis and a faster decrease in muscle pH due to depletion of oxygen during the treatment. Exposure to CO did increase the level of cortisol compared to undisturbed control fish, but the increase was less than in the water only control group. Neuroglobin, a CO binding globin, was found in salmon brain and Saccus vasculosus, a richly vascularized sac connected to the fish brain. Binding of CO to neuroglobin during sedation might possibly improve animal welfare. 相似文献