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41.
We present the design and use of an ultrathin, stretchable sensor system capable of conformal lamination onto the skin, for precision measurement and spatial mapping of levels of hydration. This device, which we refer to as a class of 'epidermal electronics' due to its 'skin-like' construction and mode of intimate integration with the body, contains miniaturized arrays of impedance-measurement electrodes arranged in a differential configuration to compensate for common-mode disturbances. Experimental results obtained with different frequencies and sensor geometries demonstrate excellent precision and accuracy, as benchmarked against conventional, commercial devices. The reversible, non-invasive soft contact of this device with the skin makes its operation appealing for applications ranging from skin care, to athletic monitoring to health/wellness assessment. 相似文献
42.
In vitro evaluation of various quinolone antibacterial agents against veterinary mycoplasmas and porcine respiratory bacterial pathogens 总被引:7,自引:0,他引:7
The in vitro activities of 12 quinolones and four antibiotics were determined against 15 veterinary mycoplasmal species and four species of bacteria commonly involved in respiratory infections in pigs. The newer quinolones were markedly more active in vitro against a wide range of mycoplasmas than nalidixic acid and the earlier quinolones. Against Mycoplasma hyopneumoniae ciprofloxacin was the most active quinolone with a geometric mean minimal inhibitory concentration (MIC) against 16 strains of 0.01 microgram ml-1 compared with 0.04 microgram ml-1 for tiamulin, 0.06 microgram ml-1 for tylosin, 0.17 microgram ml-1 for oxytetracycline and 0.23 microgram ml-1 for gentamicin. M hyosynoviae was less sensitive to the quinolones with mean MICs of 0.6 microgram ml-1 for ofloxacin and 0.7 microgram ml-1 for ciprofloxacin compared with 0.034 microgram ml-1, or less, for tiamulin. Norfloxacin and its 6-chloro analogue were both mycoplasmacidal in vitro at five or 10 times their MICs against M hyopneumoniae UCD4. Tiamulin was mycoplasmastatic. The quinolones were also active against porcine Bordetella bronchiseptica and Pasteurella multocida strains and Haemophilus species. Ciprofloxacin was the most active quinolone with mean MICs of 0.58 microgram ml-1 against B bronchiseptica (nine strains), 0.026 microgram ml-1 against P multocida (five strains) and 0.01 microgram ml-1, or less, against Haemophilus pleuropneumoniae (nine strains) and H parasuis (two strains) compared with mean MICs of from 0.5 microgram ml-1 to 64 micrograms ml-1, or more, for the antibiotics. This combination of excellent mycoplasmacidal activity against M hyopneumoniae and good antibacterial activity, suggests that the quinolones have great potential for treating respiratory infections in pigs, including enzootic pneumonia. 相似文献
43.
Phospholipids and wheat gluten blends: interaction and kinetics 总被引:1,自引:0,他引:1
Abdellatif Mohamed S.H. Gordon Rogers E. Harry-O'Kuru Debra E. Palmquist 《Journal of Cereal Science》2005,41(3):259-265
A model system comprising of lysophosphatidylcholine (LPC) and isolated gluten were used help understand the positive effect of PL on bread-loaf volume. The kinetics of the effect of gluten on the thermal properties of LPC were determined using DSC. Blends of PL and 3, 6, and 10% gluten were heated from 0 to 70 °C at rates between 3 and 19 °C/min and cooled to 0 °C. The onset and peak temperatures and ΔH were recorded. The peak temperature was used to calculate the activation energy (Ea) and Z value. The transition for pure LPC vesicle formation was detectable by DSC in the presence of gluten. Gluten increased the activation energy of LPC during vesicle formation and disruption. The increase in gluten content from 3 to 6% and then to 10% had a slight effect on the activation energy value of LPC during vesicle disruption, whereas during formation a steady increase was noticed with higher gluten additions. Overall, the ΔH of the blends showed a decrease at higher heating rate. The change in the PL activation energy in the presence of gluten is indicative of a form of interaction. 相似文献
44.
Gonçalves R Platt SR Llabrés-Díaz FJ Rogers KH de Stefani A Matiasek LA Adams VJ 《Journal of Feline Medicine and Surgery》2009,11(2):53-59
Medical records of 92 cats presented with clinical signs of spinal cord disease, which had undergone magnetic resonance imaging (MRI), were reviewed. The cats were grouped into seven categories based upon the diagnosis suggested by results of MRI, cerebrospinal fluid analysis and other diagnostic procedures: neoplastic (n=25), inflammatory or infectious (n=13), traumatic (n=8), vascular (n=6), degenerative (n=5), anomalous (n=3) and those with an unremarkable MRI (n=32). There were two independent predictors of abnormal MRI findings: severity of clinical signs and presence of spinal pain. Abnormal MRI findings and speed of onset of disease were significantly associated with survival. For the 32 cats with unremarkable MRI findings, only nine died due to spinal disease and, therefore, the median survival time (MST) was not reached (lower 95% confidence interval (CI)=970 days). For the 60 cats with abnormal MRI findings, 37 died due to their disease and the MST was 138 days (95% CI: 7-807). 相似文献
45.
Tim M. Daw Ginny C.C. Rogers Paul Mapson Jo E. Kynoch 《Aquarium Sciences and Conservation》2001,3(1-3):53-64
Following independence from Ethiopia in 1993, Eritrea resumed exploiting Red Sea and Arabian fish species for the ornamental trade in 1995 as a means to earn foreign exchange from sparsely exploited marine resources. This paper describes the findings of research conducted in 1997, in collaboration with the Eritrean Ministry of Fisheries. The capture, transport and export of aquarium fish were reviewed and potential impacts and the status of management were investigated through liaison with stakeholders and researchers. From 1995 to 1997 two companies exported approximately 60,000 fish per year, mainly to the USA, worth US$65,000 (export value). Seventy-five species (from 22 families) were exported. Damselfishes made up two-thirds of total exports but more valuable families (angelfishes and butterflyfishes) were more economically significant. To earn revenue for Eritrea, a 20% export tax was imposed, although this was calculated from declarations by the operators. The emerging nature of the trade allowed detailed monitoring by the Ministry of Fisheries. However, management efforts were constrained by a lack of capacity for enforcement and baseline research. Several potential effects of the trade exist but other, land-based impacts may be more pressing concerns for Eritrea's reefs. Research priorities for management are discussed as well as the implications of mariculture of Eritrean species by other nations. 相似文献
46.
João H Perotta Paulo A Canola Maristela CS Lopes Patrícia M Évora Paulo EB Martinez André Escobar Carlos AA Valadão 《Veterinary anaesthesia and analgesia》2014,41(4):357-364
ObjectiveTo evaluate the effects of intravenous (IV) or intramuscular (IM) hyoscine premedication on physiologic variables following IV administration of medetomidine in horses.Study designRandomized, crossover experimental study.AnimalsEight healthy crossbred horses weighing 330 ± 39 kg and aged 7 ± 4 years.MethodsBaseline measurements of heart rate (HR), cardiac index (CI), respiratory rate, systemic vascular resistance (SVR), percentage of patients with second degree atrioventricular (2oAV) block, mean arterial pressure (MAP), pH, and arterial partial pressures of carbon dioxide (PaCO2) and oxygen (PaO2) were obtained 5 minutes before administration of IV hyoscine (0.14 mg kg?1; group HIV), IM hyoscine (0.3 mg kg?1; group HIM), or an equal volume of physiologic saline IV (group C). Five minutes later, medetomidine (7.5 μg kg?1) was administered IV and measurements were recorded at various time points for 130 minutes.ResultsMedetomidine induced bradycardia, 2oAV blocks and increased SVR immediately after administration, without significant changes in CI or MAP in C. Hyoscine administration induced tachycardia and hypertension, and decreased the percentage of 2oAV blocks induced by medetomidine. Peak HR and MAP were higher in HIV than HIM at 88 ± 18 beats minute?1 and 241 ± 37 mmHg versus 65 ± 16 beats minute?1 and 192 ± 38 mmHg, respectively. CI was increased significantly in HIV (p ≤ 0.05). Respiratory rate decreased significantly in all groups during the recording period. pH, PaCO2 and PaO2 were not significantly changed by administration of medetomidine with or without hyoscine.Conclusion and clinical relevanceHyoscine administered IV or IM before medetomidine in horses resulted in tachycardia and hypertension under the conditions of this study. The significance of these changes, and responses to other dose rates, requires further investigation. 相似文献
47.
Objectives were to 1) identify risk factors affecting the longevity of beef females, 2) evaluate the utility of measures collected early in life in predicting longevity, and 3) estimate the heritability of longevity when females were culled primarily for not being pregnant following a 45-d breeding season. Data were from 1,379 Composite Gene Combination (CGC; 1/2 Red Angus, 1/4 Charolais, 1/4 Tarentaise) cows born from 1982 through 1999 at the USDA-ARS, Fort Keogh Livestock and Range Research Laboratory, Miles City, MT, and first calving at approximately 2 yr of age. The length of productive life was modeled using Cox regression to identify factors affecting the longevity of beef females. Age at first calving and calf birth weight did not influence longevity. Cows that experienced dystocia were at greater risk of being culled than those that calved without assistance (P < 0.01). On average, as breeding value for cow weight increased, the risk of being culled decreased (P < 0.01), whereas the risk of being culled increased with increasing maternal breeding values for preweaning gain (P < 0.05). Traits measured before 1 yr of age were not useful in predicting the subsequent longevity of cows. The heritability of functional longevity was estimated to be 0.14. Relatively low heritability and the lack of indicators of longevity expressed early in life suggest that genetic improvement of longevity will be difficult. Matching the genetic potential of cows for size and milk production to the production environment such that rebreeding performance is not compromised by concurrent lactation seems to be a consideration in retaining beef females when open cows are culled. 相似文献
48.
Phytochemical composition and metabolic performance-enhancing activity of dietary berries traditionally used by Native North Americans 总被引:1,自引:0,他引:1
Burns Kraft TF Dey M Rogers RB Ribnicky DM Gipp DM Cefalu WT Raskin I Lila MA 《Journal of agricultural and food chemistry》2008,56(3):654-660
Four wild berry species, Amelanchier alnifolia, Viburnum trilobum, Prunus virginiana, and Shepherdia argentea, all integral to the traditional subsistence diet of Native American tribal communities, were evaluated to elucidate phytochemical composition and bioactive properties related to performance and human health. Biological activity was screened using a range of bioassays that assessed the potential for these little-known dietary berries to affect diabetic microvascular complications, hyperglycemia, pro-inflammatory gene expression, and metabolic syndrome symptoms. Nonpolar constituents from berries, including carotenoids, were potent inhibitors of aldose reductase (an enzyme involved in the etiology of diabetic microvascular complications), whereas the polar constituents, mainly phenolic acids, anthocyanins, and proanthocyanidins, were hypoglycemic agents and strong inhibitors of IL-1beta and COX-2 gene expression. Berry samples also showed the ability to modulate lipid metabolism and energy expenditure in a manner consistent with improving metabolic syndrome. The results demonstrate that these berries traditionally consumed by tribal cultures contain a rich array of phytochemicals that have the capacity to promote health and protect against chronic diseases, such as diabetes. 相似文献
49.
50.
W A Rogers E F Donovan G J Kociba 《Journal of the American Veterinary Medical Association》1975,166(11):1092-1100
Concentrations of serum cholesterol, triglyceride, and free glycerol were neasured, and serum lipoprotein electrophoresis was performed in normal dogs and in dogs with hypothyroidism, diabetes mellitus, and acute pancreatitis. Twelve privately owned dogs and 20 Basset Hounds from a research colony served as normal subjects. Privately owned had higher serum lipid concentrations than did research dogs. On electrophorisis of normal dog serum, lipoprotein bands were detected at the beta, pre-beta, alpha-2, and alpha-1 positions. Hypercholesterolemia was associated with increased intensity of the alpha-2-lipoprotein band, and hypertriglyceridemia occurred with increased lipoprotein at the origin, or the beta or pre-beta positions. Hypothyroid dogs had normal lipid values and lipoprotein electrophoretic patterns, hypercholesterolemia with increased intensity of the alpha-2-lipoprotein band, or hypercholesterolemia and hypertiglyceridemia with prominent beta-, pre-beta, and alpha-2-lipoprotein electrophoretic patterns were changed to near-normal values after levothyroxine administration. Diabetic dogs had increased serum cholesterol and triglyceride content and a predominance of lower density lipoproteins, as detected by electrophoresis. Insulin therapy caused the lipid concentrations to decrease and the electrophoretic pattern to revert to near normal. Dogs with acute pancreatitis had moderately increased serum lipid content and electrophoretic patterns characterized by increased intensity of the beta-lipoprotein band and by altered migration of alpha-1-lipoproteins. 相似文献