Discriminating between organic matter in soil from grass and forest by near‐infrared spectroscopy     

D. Ertlen  D. Schwartz  M. Trautmann  R. Webster  D. Brunet 《European Journal of Soil Science》2010,61(2):207-216

The absorbance of near‐infrared (NIR) radiation by plants depends on the overtones of vibration, bending and stretching of the chemical bonds within their organic components. The wide variety of these bonds gives rise to characteristic NIR spectra, or ‘fingerprints’, of plant materials. Do these fingerprints remain in the soil when the plants decompose and allow discrimination between soils that have supported different types of vegetation? We have compared the NIR spectra of grassland soil with those of soil under forest in the Vosges mountains in France. Near‐infrared reflectances, R, from 370 samples of soil were recorded as A = log₁₀(1/R) at wavelengths between 1100 and 2500 nm and averaged over 10‐nm intervals to give spectra each with 140 values. A canonical variate analysis (CVA) of the raw spectra discriminated well, but not perfectly, between grassland and forest soil, with Mahalanobis distance, D, of 4.87. Standardization along the spectra to remove effects of varied mineral composition achieved complete separation between the two sources with D = 9.81. Canonical variate analysis of first and second derivatives of the spectra distinguished the two groups even better, with D = 12.27 and D = 16.65, respectively. The results show much promise for inferring past vegetative cover from NIR spectra deriving from the organic matter in the soil. The next step will be to extend these studies to see how well we can distinguish other types of vegetation from such spectra.  相似文献   

Early pedogenic evolution of constructed Technosols     

Geoffroy Séré  Christophe Schwartz  Stéphanie Ouvrard  Jean-Christophe Renat  Françoise Watteau  Geneviève Villemin  Jean Louis Morel 《Journal of Soils and Sediments》2010,10(7):1246-1254

Purpose  

Constructed soils are Technosols resulting from the deliberate combination of various artefacts. Similarly to natural soils, technogenic parent materials are transformed by pedogenic factors contributing to their evolution. This work was conducted to study the first stages of the pedogenesis of constructed soils.  相似文献   

Molecular and pharmacological characterization of the canine brainstem alpha-2A adrenergic receptor     

Schwartz DD  Jones WG  Hedden KP  Clark TP 《Journal of veterinary pharmacology and therapeutics》1999,22(6):380-386

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What is your diagnosis? Malignant liposarcoma of the right middle lung lobe     

Schwartz P  Bellah JR  Kennedy FA 《Journal of the American Veterinary Medical Association》2005,226(5):695-696

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What is your diagnosis? Primary tracheal tumor     

Schwartz P  Bellah JR  Wolfersteig D 《Journal of the American Veterinary Medical Association》2005,226(8):1299-1300

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Anthropology. Getting to know Homo erectus     

Schwartz JH 《Science (New York, N.Y.)》2004,305(5680):53-54

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Effects of adventitial inflammation of coronary artery on the formation of atherosclerotic lesions     

WANG Jian-li  GAO Chun-rong  LI Li  YUAN Zhong-rui  ZHANG Xiao-ming  LI Bo-qin  HU Wei-cheng  S.M.Schwartz 《园艺学报》2006,22(3):431-434

AIM: To study the pathogenesis of atherosclerotic lesions which were closely related to the adventitial inflammation of coronary artery (CA) in apolipoprotein E gene knockout (apoE-/-) mice. METHODS: The hearts of apoE-/- mice were cut consecutively. Three kinds of CA samples (① Infiltration of inflammatory cells at CA adventitia, without lesion; ② Infiltration of inflammatory cells at CA adventitia, with the top of extending lesion directly from aorta; ③ Infiltration of inflammatory cells at CA adventitia, with mature lesion) were chosen to represent the three stages of atherosclerotic lesion formation. HE staining, Movat staining, immunohistochemical staining and electron transmission microscopy were used respectively to identify the types of the inflammatory cells infiltrated at adventitia of coronary artery. RESULTS: The constituent ratio of macrophages which infiltrated in the CA adventitia without atherosclerotic lesions, of neutrophils which were involved in the CA adventitia with young atherosclerotic lesions and of lymphocytes in the CA adventitia with mature lesions, were 60.00%, 57.65% and 66.67%, which were higher than those in the other two groups, respectively (P<0.01). CONCLUSION: It was showed that CA adventitial inflammation might be an early event inducing the formation of atherosclerotic lesions. The CA adventitia undergoes a process from acute to chronic inflammation during the formation of atherosclerotic lesions.  相似文献   

Development of a sensitive immunoradiometric assay for detection of platelet surface-associated immunoglobulins in thrombocytopenic dogs     

Scott MA  Kaiser L  Davis JM  Schwartz KA 《American journal of veterinary research》2002,63(1):124-129

OBJECTIVE: To develop a direct assay to measure platelet surface-associated immunoglobulins (PSAIg) in dogs and to determine whether the assay is useful in the diagnosis of immune-mediated thrombocytopenia (IMT). ANIMALS: 20 healthy dogs were used to develop reference intervals, and 23 dogs with IMT and 17 with non-IMT were used to evaluate the clinical use of this assay. PROCEDURE: After optimization of platelet collection and assay conditions, concentrations of PSAIg were measured, using radiolabeled staphylococcal protein A (SpA) and polyclonal antibodies against canine IgG (anti-gamma) and IgM (anti-micro). Concentrations of PSAIg were expressed as the percentage of radiolabeled immunoglobulin detector bound. RESULTS: Cut-off values (mean + 3 SD) were as follows: SpA, 1.1%; anti-gamma, 1.3%; and anti-micro, 3.5%. Values greater than these cut-off values were considered positive. Values determined by use of radiolabeled SpA for all dogs with IMT were greater than the cut-off value; values were considered high positives (> 5 times cut-off value) for 22 of these 23 dogs. Although 9 of 17 dogs with non-IMT also had PSAIg concentrations greater than the cut-off value, values were considered high positives for only 3 of these 9 dogs. CONCLUSIONS AND CLINICAL RELEVANCE: The immunoradiometric assay developed is a reliable and sensitive method to detect PSAIg in dogs. However, to obtain accurate results, optimum temperature, time, and storage conditions must be used. Detection of increased concentrations of PSAIg in dogs presumed to have non-IMT should alert clinicians to reconsider an immune-mediated basis for the thrombocytopenia.  相似文献   

Separation anxiety syndrome in cats: 136 cases (1991-2000)     

Schwartz S 《Journal of the American Veterinary Medical Association》2002,220(7):1028-1033

OBJECTIVE: To determine whether cats develop clinical signs typical of separation anxiety syndrome (SAS) and the type and frequency of applicable clinical signs in affected cats. DESIGN: Retrospective study. ANIMALS: 136 cats with clinical signs typical of SAS in dogs. Subjects were evaluated during home visits. PROCEDURE: Medical records of pet cats evaluated for behavior problems during a 10-year period were reviewed. Medical records of cats that displayed behaviors typical of dogs with SAS (eg, inappropriate elimination, excessive vocalization, destructiveness, or self-mutilation) were more extensively examined, and cats that displayed these behaviors only when separated from an apparent attachment figure were included in the study. RESULTS: Behavior problems triggered by separation anxiety included inappropriate urination (96 cats), inappropriate defecation (48), excessive vocalization (16), destructiveness (12), and psychogenic grooming (8). Inappropriate defecation was identified in a significantly higher percentage of the neutered females in the study than in the neutered males. Seventy-five percent of the cats that urinated inappropriately urinated exclusively on the owner's bed. Psychogenic grooming was identified in 8 of the 40 neutered females but in none of the neutered males, whereas destructiveness was observed in 12 of the 92 neutered males but in none of the neutered females. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that cats can develop SAS. Sex and breed differences in the frequency of particular signs of SAS in cats may exist. Feline SAS should be considered in the differential diagnosis of anxiety-related misbehavior in cats.  相似文献   

Infective endocarditis in a dairy farmer in association with bovine Staphylococcus aureus mastitis          下载免费PDF全文

Gangbar E  Schwartz L  Gold W  Salit I 《The Canadian veterinary journal. La revue veterinaire canadienne》1993,34(11):677-678

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