Conventional and functional magnetic resonance imaging features of late subacute cortical laminar necrosis in a dog     

Neringa Alisauskaite  Adriano Wang‐Leandro  Matthias Dennler  Marta Kantyka  Simone K. Ringer  Frank Steffen  Katrin Beckmann 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(4):1759-1765

Cerebral cortical laminar necrosis (CLN) is a consequence of severe hypoxic, ischemic, or hypoglycemic events. In humans, these cortical lesions show characteristic linear T1‐weighted (T1W) hyperintensity in the late subacute stage. Limited information reporting magnetic resonance imaging (MRI) findings in dogs affected by CLN is available. A 3‐year‐old Belgian Shepherd dog was referred 8 days after sudden onset of blindness after general anesthesia. Neurological examination showed central blindness and mild ataxia. Three‐Tesla MRI examination of the brain revealed bilateral asymmetrical areas of T2‐weighted hyperintensity within the occipital, parietal, temporal, and frontal cortex, involving gray and white matter. Furthermore, linear T1W‐hyperintense lesions were found in the cerebral cortex of the same areas and showed heterogeneous contrast enhancement. Perfusion‐weighted images revealed hyperperfusion in the affected regions. Lesions were compatible with subacute CLN with corresponding edema suspected to be secondary to anesthesia‐related brain hypoxia. Three‐Tesla MRI enabled identification of the laminar pattern of the cortical lesions.  相似文献   

Einsatz von Kennzahlen und Beratungsbriefen als Controlling-Instrument für Beratung und Gartenbaupraxis an der Niederelbe     

Matthias Görgens 《Erwerbs-Obstbau》2008,50(2):41-47

The first business management analyses of fruit farms from the Altes Land (Lower Elbe Valley, Northern Germany) date back to the financial year 1956/57 and were published in 1958 by Prof. A. Löhden in the journal Mitteilungen des Obstbauversuchsringes des Alten Landes e.V. The data compiled by Löhden from the Agrarian Report were used by the Chamber of Agriculture of Hannover to evaluate the book-keeping of those fruit farms which it supported with business development grants. In the early 1980s the fruit advisory services had to implement a comparison of the book-keeping data of fruit farms. This business management advice has been expanded subsequently. At present, some 120 fruit farmers participate at the annual comparison of the Fruit Advisory Service and the Centre of Business Management in Horticulture. The use of this controlling instrument for evaluating key business data will be demonstrated in the current article on the basis of two examples.  相似文献   

Spatial scale invariance of southern Australian forest fires mirrors the scaling behaviour of fire-driving weather events   总被引：1，自引：0，他引：1  

Matthias M. Boer  Rohan J. Sadler  Ross A. Bradstock  A. Malcolm Gill  Pauline F. Grierson 《Landscape Ecology》2008,23(8):899-913

Power law frequency-size distributions of forest fires have been observed in a range of environments. The scaling behaviour of fires, and more generally of landscape patterns related to recurring disturbance and recovery, have previously been explained in the frameworks of self-organized criticality (SOC) and highly optimized tolerance (HOT). In these frameworks the scaling behaviour of the fires is the global structure that either emerges spontaneously from locally operating processes (SOC) or is the product of a tuning process aimed at optimizing the trade-offs between system yield and tolerance to risks (HOT). Here, we argue that the dominant role of self-organized or optimised fuel patterns in constraining unplanned-fire sizes, implicit in the SOC and HOT frameworks, fails to recognise the strong exogenous controls of fire spread (i.e. by weather, terrain, and suppression) observed in many fire-prone landscapes. Using data from southern Australia we demonstrate that forest fire areas and the magnitudes of corresponding weather events have distributions with closely matching scaling exponents. We conclude that the spatial scale invariance of forest fires may also be a mapping of the meteorological forcing pattern. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

Screening of sugar beet pre-breeding populations and breeding lines for resistance to Ditylenchus dipsaci penetration and reproduction     

Storelli  Alan  Minder  Alexandra  Keiser  Andreas  Kiewnick  Sebastian  Daub  Matthias  Mahlein  Anne-Katrin  Schumann  Mario  Beyer  Werner 《植物病害和植物保护杂志》2021,128(5):1303-1311

Journal of Plant Diseases and Protection - Ditylenchus dipsaci is an economically important plant-parasitic nematode affecting European sugar beets. To date, no sugar beet cultivars carrying...  相似文献   

Two newly developed Erns-based ELISAs allow the differentiation of Classical Swine Fever virus-infected from marker-vaccinated animals and the discrimination of pestivirus antibodies     

Andrea Aebischer  Matthias Müller  Martin A. Hofmann 《Veterinary microbiology》2013,161(3-4):274-285

New generations of Classical Swine Fever virus (CSFV) marker vaccines have recently been developed in order to make emergency vaccination in case of a CSF outbreak more feasible. However, the application of a marker vaccine is dependent on the availability of an accompanying discriminatory test allowing differentiation of infected from vaccinated animals (DIVA). CP7_E2alf, the most promising live marker vaccine candidate currently available, is a genetically modified Bovine Viral Diarrhea virus expressing the E2 glycoprotein of CSFV strain Alfort/187. The DIVA principle going along with CP7_E2alf is based on the detection of CSFV E^rns-specific antibodies that are raised in the host upon CSFV infection but not after vaccination with the marker vaccine. The aim of this study was to develop novel DIVA tests to be used in combination with CP7_E2alf. Two indirect ELISAs (one for screening, the other one for confirmation purposes) using bacterially expressed recombinant E^rns proteins were designed and evaluated. Both ELISAs detected CSFV-specific antibodies against a broad range of strains and genotypes, and as early as 10 days after infection. They were able to distinguish CSFV-infected pigs from pigs vaccinated with CP7_E2alf and allowed discrimination of antibodies against ruminant pestiviruses in both, sera from domestic pigs and wild boar. Sensitivity and specificity of the screening ELISA was ≥95%. Thus, the ELISAs represent promising DIVA diagnostic tools, as well as an alternative to traditional pestivirus antibody differentiation by serum neutralization test.  相似文献   

Percutaneous angiography of Patent Ductus Arteriosus in dogs: techniques, results and implications for intravascular occlusion     

Matthias Schneider DVM  Dr Med Vet  PD  Ingo Schneider DVM  Dr Med Vet.  Nicolai Hildebrandt DVM  Martin Wehner DVM 《Journal of Veterinary Cardiology》2003,5(2):359

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Effects of temperature and temperature‐humidity index on the reproductive performance of sows during summer months under a temperate climate          下载免费PDF全文

Kerstin Wegner  Christian Lambertz  Gürbüz Das  Gerald Reiner  Matthias Gauly 《Animal Science Journal》2016,87(11):1334-1339

Heat stress is known to influence sow reproduction, but it is unknown to which extent under temperate climates. Therefore, the impact of temperature and temperature‐humidity index (THI) on the reproductive performance of sows during summer months from 2009 to 2011 were studied. Reproductive parameters of 22 264 inseminations and 21 610 resulting farrowings of 22 German commercial farms were analyzed. Climatic records were available from the nearest weather station. Effects of temperature and THI at different periods of the reproductive cycle were estimated from May to September where temperatures were expected to influence climatic conditions indoors. High temperatures and THI values 5 days pre‐ and 14 days post‐breeding reduced litter size by 0.01 to 0.03 piglets (P < 0.05). Prior to farrowing, the number of liveborn piglets was reduced (P < 0.05) and of stillborns increased with rising climatic variables (P < 0.001). On the day of farrowing, reduced numbers of weaned piglets were observed when temperature and THI values were elevated (P < 0.05), but pre‐weaning mortality was not influenced (P > 0.05). In conclusion, even under temperate conditions adverse effects of climatic variables on the reproductive performance of sows are present. Thereby, the number of liveborn piglets can be considered as the most sensitive parameter to heat stress. Considering the impact of climate change and predicted heat waves, strategies to mitigate the impact of heat stress are necessary.  相似文献   

Biophysical controls of carbon flows in three successional Douglas-fir stands based on eddy-covariance measurements     

Chen J  Falk M  Euskirchen E  U KT  Suchanek TH  Ustin SL  Bond BJ  Brosofske KD  Phillips N  Bi R 《Tree physiology》2002,22(2-3):169-177

We measured net carbon flux (F(CO2)) and net H2O flux (F(H2O)) by the eddy-covariance method at three Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco)-western hemlock (Tsuga heterophylla (Raf.) Sarg.) sites located in the Wind River Valley of southern Washington State, USA. Stands were approximately 20, 40 and 450 years old and measurements were made between June 15 and October 15 of 1998 in the 40- and 450-year-old stands, and of 1999 in the 20- and 450-year-old stands. Our objectives were to determine if there were differences among the stands in: (1) patterns of daytime F(CO2) during summer and early autumn; (2) empirically modeled relationships between local climatic factors (e.g., light, vapor pressure deficit (VPD), soil water content, temperature and net radiation) and daytime F(CO2); and (3) water-use efficiency (WUE). We used the Landsberg equation, a logarithmic power function and linear regression to model relationships between F(CO2) and physical variables. Overall, given the same irradiance, F(CO2) was 1.0-3.9 mol m-2 s-1 higher (P < 0.0001 for both seasons) at the two young stands than at the old-growth stand. During summer and early autumn, F(CO2) averaged 4.2 and 6.1 mol m-2 s-1 at the 20- and 40-year-old stand, respectively. In contrast, the 450-year-old forest averaged 2.2 and 3.2 mol m-2 s-1 in 1998 and 1999, respectively. Increases in VPD were associated with reduced F(CO2) at all three stands, with the greatest apparent constraints occurring at the old-growth stand. Correlations between F(CO2) and all other environmental variables differed among ecosystems, with soil temperature showing a negative correlation and net radiation showing a positive correlation. In the old-growth stand, WUE was significantly greater (P < 0.0001) in the drier summer of 1998 (2.7 mg g-1) than in 1999 (1.0 mg g-1). Although we did not use replicates in our study, the results indicate that there are large differences in F(CO2) among Douglas-fir stands of different ages growing in the same general area, and that variations in age structure and site conditions need to be considered when scaling flux measurements from individual points to the landscape level.  相似文献   

Tree growth as indicator of tree vitality and of tree reaction to environmental stress: a review     

Matthias?DobbertinEmail author 《European Journal of Forest Research》2005,124(4):319-333

The intensive monitoring plots (Level II) of ICP Forests serve to examine the effects of air pollution and other stress factors on forest condition, including tree vitality. However, tree vitality cannot be measured directly. Indicators, such as tree growth or crown transparency, may instead be used. Tree growth processes can be ranked by order of importance in foliage growth, root growth, bud growth, storage tissue growth, stem growth, growth of defence compounds and reproductive growth. Under stress photosynthesis is reduced and carbon allocation is altered. Stem growth may be reduced early on as it is not directly vital to the tree. Actual growth must be compared against a reference growth, such as the growth of trees without the presumed stress, the growth of presumed healthy trees, the growth in a presumed stress-free period or the expected growth derived from models. Several examples from intensive monitoring plots in Switzerland illustrate how tree-growth reactions to environmental stresses may serve as vitality indicator. Crown transparency and growth can complement each other. For example, defoliation by insects becomes first visible in crown transparency while stem growth reaction occurs with delay. On the other hand, extreme summer drought as observed in large parts of Europe in 2003 affects stem growth almost immediately, while foliage reduction becomes only visible months later. Residuals of tree growth models may also serve as indicators of changed environmental conditions. Certain stresses, such as drought or insect defoliation cause immediate reactions and are not detectable in five-year growth intervals. Therefore, annual or inter-annual stem growth should be assessed in long-term monitoring plots. An erratum to this article can be found at  相似文献   

Performance of thermomechanical wood fibers in polypropylene composites     

Oliver Mertens  Kim C. Krause  Matthias Weber  Andreas Krause 《Wood material science & engineering》2020,15(2):114-122

ABSTRACT

Thermomechanical wood fibers, as usually used for medium density fiberboard or cardboard production, feature promising characteristics, like a high aspect ratio, for the utilization in thermoplastic composites. The present study investigates the influence of fiber loading and fiber geometry on the mechanical properties of wood-polypropylene composites in order to confirm the results that were found in a previously published literature review. Composites were compounded at fiber contents from 20 to 60 wt.%, using a co-rotating twin-screw extruder and subsequently injection molded to test specimens. Field emission scanning electron microscopy was carried out to evaluate the fracture morphology of the composites. Fiber length was evaluated using an applying a dynamic image analysis system. Compounding reduced fiber lengths up to 97%. The mechanical properties decreased with increasing fiber content for composites without a coupling agent. Strength properties peaking at a fiber content of 50?wt.% for composites containing MAPP. Tensile strength and flexural strength reached 48.1 and 76.4 MPa, respectively. However, it was found that the processing of these fibers into conventional compounding equipment is still challenging.  相似文献