Applications of X‐ray computed tomography for examining biophysical interactions and structural development in soil systems: a review     

J. R. Helliwell  C. J. Sturrock  K. M. Grayling  S. R. Tracy  R. J. Flavel  I. M. Young  W. R. Whalley  S. J. Mooney 《European Journal of Soil Science》2013,64(3):279-297

Soil systems are characterized by the spatial and temporal distribution of organic and mineral particles, water and air within a soil profile. Investigations into the complex interactions between soil constituents have greatly benefited from the advent of non‐invasive techniques for structural analysis. In this paper we present a review of the application of one such technique, X‐ray computed tomography (CT), for studies of undisturbed soil systems, focusing on research during the last 10 years in particular. The ability to undertake three‐dimensional imaging has provided valuable insights regarding the quantitative assessment of soil features, in a way previously unachievable because of the opaque nature of soil. A dynamic approach to the evaluation of soil pore networks, hydro‐physical characteristics and soil faunal behaviour has seen numerous scanning methodologies employed and a diverse range of image analysis protocols used. This has shed light on functional processes across multiple scales whilst also bringing its own challenges. In particular, much work has been carried out to link a soil's porous architecture with hydraulic function, although new technical improvements allowing the characterization of organic matter and the influence of soil biota on structural development are showing great promise. Here we summarize the development of X‐ray CT in soil science, highlight the major issues relating to its use, outline some of the applications for overcoming these challenges and describe the potential of future technological advances for non‐invasive soil characterization through integration with other complementary techniques.  相似文献   

Conservation. Ecosystem services for 2020     

Perrings C  Naeem S  Ahrestani F  Bunker DE  Burkill P  Canziani G  Elmqvist T  Ferrati R  Fuhrman J  Jaksic F  Kawabata Z  Kinzig A  Mace GM  Milano F  Mooney H  Prieur-Richard AH  Tschirhart J  Weisser W 《Science (New York, N.Y.)》2010,330(6002):323-324

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Biochar enhances soil hydraulic function but not soil aggregation in a sandy loam     

H. Zhou  H. Fang  Q. Zhang  Q. Wang  C. Chen  S. J. Mooney  X. Peng  Z. Du 《European Journal of Soil Science》2019,70(2):291-300

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Dynamic adrenal function testing in eight dogs with hyperadrenocorticism associated with adrenocortical neoplasia.     

E J Norman  H Thompson  C T Mooney 《The Veterinary record》1999,144(20):551-554

The results of adrenocorticotropin (ACTH) stimulation and low-dose dexamethasone suppression tests (LDDST) were evaluated retrospectively in eight dogs with clinical signs of hyperadrenocorticism arising from functional adrenocortical tumours, and compared with the results from 12 dogs with confirmed pituitary-dependent hyperadrenocorticism (PDH). The post-ACTH cortisol concentration in the dogs with adrenocortical tumours ranged from 61 to 345-6 nmol/litre (median 251.5 nmol/litre) and they were within the reference range (150 to 450 nmol/litre) in five and unexpectedly low (< 150 nmol/litre) in three dogs. Both the basal and post-ACTH cortisol concentrations were significantly lower in the dogs with adrenocortical neoplasia than in the dogs with PDH. Eight hours after the LDDST, only two of six dogs with adrenocortical tumours had a cortisol concentration above 30 nmol/litre, and the median resting, three, and eight-hour cortisol concentrations were 31.5, 23.0, and 22.7 nmol/litre respectively. There was no significant cortisol suppression during the LDDST, although interpretation was complicated by the low cortisol concentrations, but two dogs showed a pattern of apparent suppression. Two dogs with adrenal tumours showed a diagnostically significant increase in 17-OH-progesterone concentration in response to ACTH although their cortisol concentrations did not increase greatly. These results differ from previous reports of the response of functional adrenal tumours to dynamic endocrine tests.  相似文献   

Three-dimensional visualization and quantification of soil macroporosity and water flow patterns using computed tomography   总被引：3，自引：0，他引：3  

S.J. Mooney 《Soil Use and Management》2002,18(2):142-151

Abstract. Efforts to assess the role of soil structure in soil and water processes have been limited by data based on two dimensional geometry or disturbed samples. Computed tomography (CT) is a non-invasive technique that allows for the three dimensional, non-destructive examination of heterogeneous materials. X-ray CT scanning was used to acquire serial images of contrasting soil types that could be used to render, and hence, quantify important soil constituents in three dimensions. By repeating the scanning techniques after an infiltration period, it was also possible to examine the nature of water movement in real time. Macropore architecture between different soil types was highly variable and generally appeared as unconnected pore segments at the resolution examined. As expected, water flow characteristics were similar to macropore structure, with wetting patterns resembling both Darcian and preferential flow identified in different soils. From this, it was found that in the sandy clay soil c . 90% of macropore space was active following infiltration, compared with c . 50% for the sandy loam soil. In addition, it was possible to visualize the three dimensional distribution of stones and other mineral material. The results illustrated the benefits of computed tomography over more conventional analyses of soil structure, and its potential as a tool for examining dynamic soil processes. However, problems associated with accessibility, resolution and artefacts still provide limitations of the technique.  相似文献   

Treatment and prognostic factors in lymphoma in cats: 103 cases (1977-1981)     

S C Mooney  A A Hayes  E G MacEwen  R E Matus  A Geary  B A Shurgot 《Journal of the American Veterinary Medical Association》1989,194(5):696-702

The records of 103 cats with lymphoma that underwent chemotherapy were reviewed. Diagnosis was confirmed by cytologic or histopathologic examination of appropriate tissue specimens. Sixty-four cats (62%) had a complete response to chemotherapy (median survival time, 7 months); 21 cats (20%) had a partial response (median survival time, 2.5 months); and 18 cats had a minimal response (median survival time, 1.5 months). Seventy-seven cats (75%) died of recurrent or progressive lymphoma, 9 cats died of feline leukemia-related anemia, 13 cats died of unrelated causes, and 4 cats were alive. Stage of disease was significantly (P = 0.009) related to response to treatment, and stage of disease and FeLV status were both significantly (P = 0.002 and P less than 0.001, respectively) related to survival.  相似文献   

Exchange of materials between terrestrial ecosystems and the atmosphere   总被引：3，自引：0，他引：3  

Mooney HA  Vitousek PM  Matson PA 《Science (New York, N.Y.)》1987,238(4829):926-932

Many biogenic trace gases are increasing in concentration or flux or both in the atmosphere as a consequence of human activities. Most of these gases have demonstrated or potential effects on atmospheric chemistry, climate, and the functioning of terrestrial ecosystems. Focused studies of the interactions between the atmosphere and the biosphere that regulate trace gases can improve both our understanding of terrestrial ecosystems and our ability to predict regional-and global-scale canges in atmospheric chemistry.  相似文献   

The uptake of different tillage practices in England     

Kamal Alskaf  Debbie L. Sparkes  Sacha J. Mooney  Sofie Sjögersten  Paul Wilson 《Soil Use and Management》2020,36(1):27-44

Reduced tillage systems have been argued to provide several potential benefits to soil, environment and to farm incomes. In England, while many farms have partially adopted such practices, a large proportion of arable farmers do not undertake reduced tillage in any form. This paper analyses the rationale for and uptake of different cultivation techniques, including analysis of the barriers to adoption of reduced tillage, aiming to benefit policymakers and researchers and increase the spread of smart agricultural practices. Based on a postal questionnaire, we estimated that 47.6% of English arable land is cultivated using minimum-tillage and 7% under no-tillage. As farm size increased, so did the probability of reduced tillage uptake. Furthermore, farms growing combinable crops were more likely to utilize reduced tillage approaches than other farm types. Soil type, weed control and weather conditions were noted as the main drivers for ‘strategic’ and ‘rotational’ ploughing, constraining continuous reduced tillage use. To effect greater reduced tillage uptake, greater communication between researchers and farmers is needed to facilitate the implementation of sustainable soil management solutions, supported by current legislation permitting responsible herbicide use in arable production. Financial support to access reduced tillage machinery may also be required for farmers operating smaller holdings. Adopting reduced tillage is a continuous learning process requiring ongoing training and information gathering; supporting a network of reduced tillage ‘farmer champions’ would facilitate practical knowledge exchange, allow farmers to observe soil improvements, understand transition phase barriers and ultimately encourage increased reduced tillage uptake.  相似文献   

Comparison of manual and laboratory PCV and total protein using EDTA and lithium heparin canine samples     

A. Tamborini  S. Papakonstantinou  A. Brown  S. Brennan  R. E. Shiel  J. N. Mills  C. T. Mooney 《The Journal of small animal practice》2014,55(5):258-264

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Diagnosis and management of diabetes mellitus in five cats with somatotrophic abnormalities     

E J Norman  C T Mooney 《Journal of Feline Medicine and Surgery》2000,2(4):406-190

The clinical findings and management of five cats with abnormalities consistent with acromegaly were examined retrospectively. Growth hormone (GH) concentrations were elevated in four cats. In one, a minimal elevation of GH was accompanied by a marked elevation in insulin-like growth factor-1 (IGF-1). Insulin-like growth factor-1 concentrations supported the diagnosis in three of four cats measured, but was not elevated initially in one cat, despite a markedly elevated GH concentration. These findings suggest that elevated IGF-1 concentrations are a reliable indicator of acromegaly, but that values within the reference range do not exclude such a diagnosis. Clinical signs of acromegaly were similar to those previously reported, although upper respiratory stridor occurred in one cat, and insulin-resistant diabetes mellitus was not a consistent feature. Despite the lack of a widely available definitive treatment for acromegaly, good control of the clinical signs of diabetes mellitus can be achieved for long periods despite high doses of insulin often being required.  相似文献