Three-dimensional carbon nanotube electrodes for extracellular recording of cardiac myocytes     

C Nick  R Joshi  JJ Schneider  C Thielemann 《Biointerphases》2012,7(1-4):58

Low impedance at the interface between tissue and conducting electrodes is of utmost importance for the electrical recording or stimulation of heart and brain tissue. A common way to improve the cell-metal interface and thus the signal-to-noise ratio of recordings, as well as the charge transfer for stimulation applications, is to increase the electrochemically active electrode surface area. In this paper, we propose a method to decrease the impedance of microelectrodes by the introduction of carbon nanotubes (CNTs), offering an extremely rough surface. In a multistage process, an array of multiple microelectrodes covered with high quality, tightly bound CNTs was realized. It is shown by impedance spectroscopy and cardiac myocyte recordings that the transducer properties of the carbon nanotube electrodes are superior to conventional gold and titanium nitride electrodes. These findings will be favorable for any kind of implantable heart electrodes and electrophysiology in cardiac myocyte cultures.  相似文献   

Single-dose oral pharmacokinetics of pergolide mesylate in healthy adult mares     

Gehring R  Beard L  Wright A  Coetzee J  Havel J  Apley M 《Veterinary therapeutics : research in applied veterinary medicine》2010,11(1):E1-E8

This pilot study evaluated protection of an equine autogenous bacterin-toxoid vaccine against Corynebacterium pseudotuberculosis infection. Twenty-four BALB/c mice were inoculated with two doses of bacterin-toxoid vaccine or two injections of a placebo. Clinical, microbiologic, and pathologic outcomes were assessed after intradermal infection with one of two equine-origin C. pseudotuberculosis strains. Mice receiving bacterin-toxoid from fast-growing C. pseudotuberculosis showed significant protection from challenge infection, as evidenced by a higher survival rate, fewer gross and histopathologic lesions, and lower bacterial levels on culture. Successful protection via a vaccine against equine internal abscesses might provide supplementary management options against an important, potentially fatal disease.  相似文献   

Length curves and volume functions for guadua bamboo (Guadua angustifolia Kunth) for the coffee region of Colombia     

Juan Carlos Camargo García  Christoph Kleinn 《European Journal of Forest Research》2010,129(6):1213-1222

Three models for the prediction of bamboo culm length and two for culm volume were fitted from data of 303 guadua bamboo (Guadua angustifolia Kunth) culms. Data are from 101 temporary inventory plots systematically distributed over the coffee region of Colombia (inventory area about 1,029,525 ha). Linear and non-linear regression models were used, and the precision of the models was evaluated by cross-validation. The models were compared by studying the adjusted coefficient of determination, the bias, mean square error and Akaike’s information criterion and by the F-test that compares predicted and observed values. For culm length, the best fit showed models that included predictor variables related to stand characteristics such as quadratic mean diameter and number of culms per ha. For culm volume prediction, the inclusion of culm length improved the model significantly. For the simple form factor model, precision of prediction was least. The models developed are useful in facilitating the estimation of stand characteristics that are relevant for the silvicultural management of Guadua stands and also for the assessment of their environmental services (such as carbon sequestration).  相似文献   

Efficacy of Clausena anisata and Plectranthus glandulosus leaf powder against Prostephanus truncatus (Coleoptera: Bostrichidae) and two strains of Sitophilus zeamais (Coleoptera: Curculionidae) on maize     

Elias Nchiwan Nukenine  Cornel Adler  Christoph Reichmuth 《Journal of pest science》2010,83(2):181-190

Powdered leaves of Clausena anisata and Plectranthus glandulosus were evaluated on Cameroonian and German strains of Sitophilus zeamais and Prostephanus truncatus for their insecticidal activities, the effects on progeny production, grain damage and population increase by admixing powders and maize grains. The two powders caused significant mortality of the three insects with P. glandulosus being far more effective than C. anisata. P. truncatus was less susceptible to P. glandulosus powder compared with the two strains of S. zeamais. The German strain (LD₅₀ = 2.75 g/100 g grain) of S. zeamais was less susceptible to P. glandulosus powder than the Cameroonian strain (LD₅₀ = 1.86 g/100 g grain). P. glandulosus unlike C. anisata powder, considerably reduced grain damage, progeny production and population increase. This study shows that there is a great potential for the powder of P. glandulosus as a promising grain protectant for integration within the subsistence farming systems of sub-saharan Africa.  相似文献   

Above- and belowground responses to tree thinning depend on the treatment of tree debris     

Suzanne M. Owen  Carolyn Hull Sieg  Catherine A. Gehring  Matthew A. Bowker 《Forest Ecology and Management》2009

Mechanical mastication is increasingly prescribed for wildfire mitigation, yet little is known about the ecological impacts of this fuels treatment. Mastication shreds trees into woodchips as an alternative to tree thinning and burning the resulting slash, which can create soil disturbances that favor exotic plants. Previous research on mastication has not simultaneously considered both the responses of soil organisms and understory plant communities. We compared mastication to slash pile burning (both 6-months and 2.5-years post-treatment) and untreated controls in pinyon–juniper (Pinus edulis–Juniperus osteosperma) woodland and measured soil properties, arbuscular mycorrhizal fungi (AMF) and understory plant composition. Our results showed that slash pile burns had severely degraded soil properties and low AMF abundance and richness compared to untreated or mastication plots. Pile burns were dominated by exotic plant species and had approximately 6× less understory plant abundance and richness than untreated plots. Only two variables differed between mastication and untreated plots 6-months post-treatment: mastication had lower soil temperature and higher soil moisture. Mastication plots 2.5-years post-treatment had more plant cover and richness than untreated plots or pile burns, although non-native Bromus tectorum cover was also greater and AMF spore richness was lower than untreated plots. The structural equation model (SEM) we developed showed that plant cover strongly influenced AMF abundance (0.50) and both plant cover (0.36) and AMF (0.31) positively influenced soil stability. In the short-term, mastication is a preferable method as it creates fewer disturbances than pile burning; however long-term impacts of mastication need further study as this practice could affect native plant communities. Our results suggest that the manner in which woody debris is treated following tree thinning has an important influence on soil stability and native plant biodiversity.  相似文献   

Root biomass in a shifting cultivation system in the eastern periphery of Amazonia,and contribution of the babassu palm     

João Thiago Rodrigues de Sousa  Flávio Henrique Reis Moraes  Christoph Gehring 《Agroforestry Systems》2016,90(2):351-360

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Stem quality assessment in European National Forest Inventories: an opportunity for harmonised reporting?     

Michal Bosela  John Redmond  Miloš Kučera  Gheorghe Marin  Radim Adolt  Thomas Gschwantner  Rudolf Petráš  Kari Korhonen  Andrius Kuliešis  Gintaras Kulbokas  Christoph Fischer  Adrian Lanz 《Annals of Forest Science》2016,73(3):635-648

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Adapting Douglas-fir forestry in Central Europe: evaluation,application, and uncertainty analysis of a genetically based model     

Debojyoti Chakraborty  Tongli Wang  Konrad Andre  Monika Konnert  Manfred J. Lexer  Christoph Matulla  Lambert Weißenbacher  Silvio Schueler 《European Journal of Forest Research》2016,135(5):919-936

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Enhanced deposition of nitrate alters microbial cycling of N in a subtropical forest soil     

Wenlong Gao  Liang Kou  Jinbo Zhang  Christoph Müller  Huiming Wang  Hao Yang  Shenggong Li 《Biology and Fertility of Soils》2016,52(7):977-986

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Evaluation of skin sensitivity after shock wave treatment in horses     

Waldern NM  Weishaupt MA  Imboden I  Wiestner T  Lischer CJ 《American journal of veterinary research》2005,66(12):2095-2100

OBJECTIVE: To evaluate the effects of shock wave treatment on cutaneous nerve function, compared with the effects of local nerve block and sedation. ANIMALS: 18 clinically sound Swiss Warmbloods. PROCEDURE: Horses were randomly allocated to 3 groups and received different amounts and types of shock waves (extracorporeal shock wave treatment [ESWT] or radial pressure wave treatment [RPWT]). Horses were sedated with xylazine and levomethadone. Shock waves were applied to the lateral palmar digital nerve at the level of the proximal sesamoid bones on 1 forelimb. Skin sensitivity was evaluated by means of an electrical stimulus at the coronary band before and 5 minutes after sedation and at 4, 24, and 48 hours after application of ESWT or RPWT. On the contralateral forelimb, skin sensitivity was tested before and 10 minutes after an abaxial sesamoid nerve block. RESULTS: No significant changes in skin sensitivity were detected, regardless of the shock wave protocol applied. Mean reaction thresholds after sedation were more than twice the baseline thresholds. After the abaxial sesamoid block, no reaction was recorded in any of the horses. CONCLUSIONS AND CLINICAL RELEVANCE: Application of ESWT or RPWT to the palmar digital nerve had no effect on cutaneous sensation distal to the treated region for at least 2 days after application. The analgesic effect of sedation on reaction to electrical stimuli was distinct but varied among horses.  相似文献