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321.
Journal of Plant Diseases and Protection - The study describes the development and employment of plant tests based on artificial inoculation of seeds or the potting substrate for evaluating the...  相似文献   
322.
This report describes a rare case of squamous cell carcinoma invading the right temporomandibular joint, right guttural pouch, and calvarium. Radiography, computed tomography, and histopathology were performed in the diagnostic workup. Computed tomography depicted more accurately than radiography the invasive nature, exact location, and extent of the lesion.  相似文献   
323.
The survey and continuing inventory in the Bavarian Forest National Park of deadwood areas resulting from a spruce bark beetle calamity are being performed by means of visual evaluation of colour infrared aerial photographs. With the aid of the object-oriented image analysis software eCognition, it was possible to develop a partially automated method for this purpose. In order to verify the classification results, a test area was classified, and the results compared with those obtained by the previously used method. In addition, the classification results from two consecutive years were compared, and accuracy assessment methods were used to scrutinize the results. Classification in the deadwood areas yielded a total classification accuracy of 91.5%. In regard to objectivity and degree of detail, the newly developed method is significantly superior to the former method, which is based on visual interpretation with a stereo workstation. One problem, however, was the insufficient spatial accuracy of the respective orthophotos. Because of this, it was not possible to detect changes over the course of specified time intervals. Therefore, a practical application of this method would require that the orthophotos from various dates or times be precisely spatially assigned. This requirement can be achieved with the production of new orthophotos.  相似文献   
324.
  • ? Five temperate broad-leaved tree species were compared with respect to their water consumption strategies under ample and restricted water supply. We measured synchronously leaf conductance (g L) in the sun canopy, xylem sap flux (J s) and leaf water potential (predawn, ψpd and noon, ψnoon) in adult trees in a mixed stand and related them to the fluctuations in vapor pressure deficit (D) and soil moisture.
  • ? Maximum g L was particularly high in F. excelsior, C. betulus and T. cordata and revealed a higher D sensitivity. ψpd remained constantly high in A. pseudoplatanus, C. betulus and F. excelsior, but decreased in T. cordata and F. sylvatica with decreasing soil moisture.
  • ? J sddecreased linearly with decreasing soil matrix potential in all species except for F. excelsior. Apparent hydraulic conductance in the soil-to-leaf flow path (L c) was higher in A. pseudoplatanus than in the other species.
  • ? F. sylvatica maintained a low maximum g L and reduced J sd markedly upon drought, but faced severe decreases in ψpd and ψnoon. F. excelsior represents an opposite strategy with high maximum g L and stable ψpd.
  • ? The species drought sensitivity increases in the sequence F. excelsior < C. betulus < T. cordata < A. pseudoplatanus < F. sylvatica.
  •   相似文献   
    325.

    Purpose  

    The presented study investigated on contamination of suspended particulate matter (SPM) in rivers that was sampled long-term and with higher frequency during a flood event at the river Rhine. It was conducted to determine in vitro biological effects as well as to identify and quantify compound classes and effective contaminants. Research was part of investigation on hazards of contaminants bound to SPM to inundated sites and retention areas that are inundated during flood events.  相似文献   
    326.
    327.
    Regulatory T cells (Tregs) are known in humans and mice from last 15 years, and several studies led to a detailed knowledge on their phenotype, functions, and role in various immune reactions. In swine, the existence of Tregs was first demonstrated in 2008 and research is still at the beginning. Nevertheless, basic information regarding phenotype, mechanisms and targets of suppression, as well as implications in transplantation and some diseases are available. Purpose of this review is to give a brief summary of the current knowledge about porcine Tregs.  相似文献   
    328.
    Incoming sensory information is often ambiguous, and the brain has to make decisions during perception. "Predictive coding" proposes that the brain resolves perceptual ambiguity by anticipating the forthcoming sensory environment, generating a template against which to match observed sensory evidence. We observed a neural representation of predicted perception in the medial frontal cortex, while human subjects decided whether visual objects were faces or not. Moreover, perceptual decisions about faces were associated with an increase in top-down connectivity from the frontal cortex to face-sensitive visual areas, consistent with the matching of predicted and observed evidence for the presence of faces.  相似文献   
    329.
    Here we present the direct observation of macroscopic quantum properties in an all high-critical-temperature superconductor d-wave Josephson junction. Although dissipation caused by low-energy excitations is expected to strongly suppress macroscopic quantum effects, we demonstrate energy level quantization in our d-wave Josephson junction. The result indicates that the role of dissipation mechanisms in high-temperature superconductors has to be revised, and it may also have consequences for the class of solid-state "quiet" quantum bits with superior coherence time.  相似文献   
    330.
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