Influence of early re-spacing on Sitka spruce branch structure     

David Auty  Aaron R. Weiskittel  Alexis Achim  John R. Moore  Barry A. Gardiner 《Annals of Forest Science》2012,69(1):93-104

• Context   

The frequency, size, and insertion angle of primary branches are important determinants of wood quality and can be significantly influenced by silvicultural activities.  相似文献   

Detection of pulsed gamma rays above 100 GeV from the Crab pulsar     

VERITAS Collaboration  Aliu E  Arlen T  Aune T  Beilicke M  Benbow W  Bouvier A  Bradbury SM  Buckley JH  Bugaev V  Byrum K  Cannon A  Cesarini A  Christiansen JL  Ciupik L  Collins-Hughes E  Connolly MP  Cui W  Dickherber R  Duke C  Errando M  Falcone A  Finley JP  Finnegan G  Fortson L  Furniss A  Galante N  Gall D  Gibbs K  Gillanders GH  Godambe S  Griffin S  Grube J  Guenette R  Gyuk G  Hanna D  Holder J  Huan H  Hughes G  Hui CM  Humensky TB  Imran A  Kaaret P  Karlsson N  Kertzman M  Kieda D  Krawczynski H  Krennrich F  Lang MJ 《Science (New York, N.Y.)》2011,334(6052):69-72

We report the detection of pulsed gamma rays from the Crab pulsar at energies above 100 giga-electron volts (GeV) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) array of atmospheric Cherenkov telescopes. The detection cannot be explained on the basis of current pulsar models. The photon spectrum of pulsed emission between 100 mega-electron volts and 400 GeV is described by a broken power law that is statistically preferred over a power law with an exponential cutoff. It is unlikely that the observation can be explained by invoking curvature radiation as the origin of the observed gamma rays above 100 GeV. Our findings require that these gamma rays be produced more than 10 stellar radii from the neutron star.  相似文献   

The role of endosymbiotic Wolbachia bacteria in the pathogenesis of river blindness     

Saint André Av  Blackwell NM  Hall LR  Hoerauf A  Brattig NW  Volkmann L  Taylor MJ  Ford L  Hise AG  Lass JH  Diaconu E  Pearlman E 《Science (New York, N.Y.)》2002,295(5561):1892-1895

Parasitic filarial nematodes infect more than 200 million individuals worldwide, causing debilitating inflammatory diseases such as river blindness and lymphatic filariasis. Using a murine model for river blindness in which soluble extracts of filarial nematodes were injected into the corneal stroma, we demonstrated that the predominant inflammatory response in the cornea was due to species of endosymbiotic Wolbachia bacteria. In addition, the inflammatory response induced by these bacteria was dependent on expression of functional Toll-like receptor 4 (TLR4) on host cells.  相似文献   

Monitoring protein structural changes and hydration in bovine meat tissue due to salt substitutes by Fourier transform infrared (FTIR) microspectroscopy     

Perisic N  Afseth NK  Ofstad R  Kohler A 《Journal of agricultural and food chemistry》2011,59(18):10052-10061

The objective of this study was to investigate the influence of NaCl and two salt substitutes, MgSO4 and KCl, in different concentrations (1.5, 6.0, and 9.0%) on meat proteins by using Fourier transform infrared (FTIR) microspectroscopy. Hydration properties and secondary structural properties of proteins were investigated by studying the amide I, amide II, and water regions (3500-3000 cm(-1)) in FTIR spectra. By applying multivariate analysis (PCA and PLSR), differences between samples according to salt concentration and salt type were found and correlated to spectral bands. The most distinctive differences related to salt type were obtained by using the water region. It was found that samples salted with MgSO4 exhibited hydration and subsequent denaturation of proteins at lower concentrations than those salted with NaCl. Samples salted with KCl brines showed less denaturation even at the 9.0% concentration. The FTIR results were further supported by water-binding capacity (WBC) measurements.  相似文献   

Atherosclerosis with multifocal myocardial infarction in a Pacific walrus (Odobenus rosmarus divergens Illiger).     

Achim D Gruber  Martin Peters  Andreas Knieriem  Peter Wohlsein 《Journal of zoo and wildlife medicine》2002,33(2):139-144

A 25-yr-old male captive walrus (Odobenus rosmarus divergens Illiger) died after suffering from periods of inactivity, anorexia, and weight loss for 8 wk. Necropsy revealed prominent, generalized atherosclerosis of cardiac arteries with widespread chronic myocardial infarction. Severe disseminated myocardial fibrosis most likely resulted in insidious cardiac failure that was ultimately the cause of death. Bouts of abdominal pain and disseminated cutaneous ulcers that had been observed 3 and 4 days before death, respectively, were attributed to circulatory failure and thrombosis. The cause of the vascular lesions remains unknown. When compared with humans, atherosclerosis is rare in animals and has not been described in a walrus.  相似文献   

Influence of climatic conditions and soil properties on 137Cs vertical distribution in selected Chilean soils     

Paulina Schuller  Achim Ellies  Josef Handl 《植物养料与土壤学杂志》1997,160(3):423-426

Long-term downward distribution of global fallout ¹³⁷Cs was studied in different soil types, in natural and semi-natural environments of four Chilean climatic zones. The ¹³⁷Cs soil content showed an exponential decrease with depth; relaxation depth ranged from 0.9 cm in the polar climate environment up to 6.8 cm in the mesothermal warm summer one. In the Antarctic and Westpatagonic ecosystems the long freezing periods delayed the ¹³⁷Cs leaching. In temperate and tropical climate zones, primarily the rates of annual rainfall and volume of coarse soil pores control the radionuclide's distribution in the soil profiles.  相似文献   

Pharmacokinetics and pulmonary distribution of gamithromycin after intravenous administration in foals          下载免费PDF全文

S. Berlin  T. Randow  E. Scheuch  M. Grube  M. Venner  W. Siegmund 《Journal of veterinary pharmacology and therapeutics》2017,40(4):406-410

The long‐acting azalide antibiotic gamithromycin is marketed for intramuscular treatment of bovine and swine infections. Off‐label use in foals leads to severe local lesions likely caused by hyperosmolality of the injected solution. We provide evidence from a pharmacokinetic study in 10 warm‐blooded healthy foals for intravenous bolus injection of gamithromycin diluted in distilled water to be a safe and well tolerated alternative. By intravenous dosing, markedly higher plasma exposure and better penetration into bronchoalveolar lavage cells but lower distribution into epithelial lining fluid are achieved as after intramuscular or subcutaneous administration. Intravenously injected gamithromycin was tolerated without any adverse drug reactions. The protocols for treatment of equine pulmonary infections caused by Rhodococcus equi should be revised accordingly.  相似文献   

Pharmacological indices and pulmonary distribution of rifampicin after repeated oral administration in healthy foals          下载免费PDF全文

S. Berlin  A. Kirschbaum  L. Spieckermann  S. Oswald  M. Keiser  M. Grube  M. Venner  W. Siegmund 《Equine veterinary journal》2017,49(5):618-623

  相似文献   

Crypthecodinium cohnii Growth and Omega Fatty Acid Production in Mediums Supplemented with Extract from Recycled Biomass     

Elina Didrihsone  Konstantins Dubencovs  Mara Grube  Karlis Shvirksts  Anastasija Suleiko  Arturs Suleiko  Juris Vanags 《Marine drugs》2022,20(1)

Crypthecodinium cohnii is a marine heterotrophic dinoflagellate that can accumulate high amounts of omega-3 polyunsaturated fatty acids (PUFAs), and thus has the potential to replace conventional PUFAs production with eco-friendlier technology. So far, C. cohnii cultivation has been mainly carried out with the use of yeast extract (YE) as a nitrogen source. In the present study, alternative carbon and nitrogen sources were studied: the extraction ethanol (EE), remaining after lipid extraction, as a carbon source, and dinoflagellate extract (DE) from recycled algae biomass C. cohnii as a source of carbon, nitrogen, and vitamins. In mediums with glucose and DE, the highest specific biomass growth rate reached a maximum of 1.012 h⁻¹, while the biomass yield from substrate reached 0.601 g·g⁻¹. EE as the carbon source, in comparison to pure ethanol, showed good results in terms of stimulating the biomass growth rate (an 18.5% increase in specific biomass growth rate was observed). DE supplement to the EE-based mediums promoted both the biomass growth (the specific growth rate reached 0.701 h⁻¹) and yield from the substrate (0.234 g·g⁻¹). The FTIR spectroscopy data showed that mediums supplemented with EE or DE promoted the accumulation of PUFAs/docosahexaenoic acid (DHA), when compared to mediums containing glucose and commercial YE.  相似文献   

Monitoring the dynamics of wheat stem elongation: genotypes differ at critical stages     

Lukas Kronenberg  Kang Yu  Achim Walter  Andreas Hund 《Euphytica》2017,213(7):157

Stem elongation is a critical phase for yield formation in wheat (Triticum aestivum). This study proposes the use of terrestrial laser scanning (TLS) for phenotyping of growth dynamics during wheat stem elongation in high temporal resolution and high throughput in the field. TLS was implemented on a novel field phenotyping platform carrying a cable suspended sensor head moveable in 3D over a 1 ha field. Canopy height was recorded on 335 winter wheat genotypes across two consecutive years. Scans were done in 3-d intervals during the stem elongation phase. Per day, 714 plots (two replications plus checks) were scanned within 3.5 h. The results showed that canopy height increased linearly with thermal time. Based on this linearity, 15 and 95% of final height were used as proxy measures for the onset and termination of stem elongation, respectively. We observed high heritability between 0.76 and 0.91 for the onset, termination and duration of stem elongation. The onset of stem elongation showed a positive covariance with the termination of stem elongation and final height indicating some regulatory dependencies. Yet there was no apparent relationship between onset and duration of stem elongation. Due to its precision, the TLS method allows to measure the dynamics of stem elongation in large sets of genotypes. This in turn offers opportunities to investigate the genetic control of the transitions between early vegetative growth, stem elongation and flowering. Understanding the genetic control of these transitions is an important milestone towards knowledge-based crop improvement.  相似文献