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81.
Riparian specialists, such as the Crimson Finch (Estrildidae: Neochmia phaeton), are vulnerable to declines in habitat quality, including alterations of flow regime associated with dam construction. Crimson Finches persisted and bred in substantial numbers following two large floods in the Isaac–Connors catchment in early 2008. Major flooding was not detrimental to nesting and breeding success, although the immediate post‐flood period was identified as a bottleneck in the availability of riparian grass seed. Crimson Finches nested at 16 m or more above the normal river level (compared with an average of 2–3 m elsewhere in Northern Australia); indicating that they have adapted to the extreme flood peaks in the Fitzroy River basin. The tall river‐associated grass Chionachne cyathopoda was a key habitat plant, retaining seed well into the dry season when most other grasses are expended. It also provided abundant seeds following floods, coinciding with peaks in abundance of dependent young finches. The adaptations of both Crimson Finches and Chionachne suggest that increased flooding, predicted by climate change, is unlikely to be a problem. In contrast, a proposed dam on the Connors River may be a threat. River regulation that reduces peaks of major floods may favour introduced riparian grasses over flood adapted native grasses such as Chionachne. Any change in the quantity of this species could be detrimental to persistence of Crimson Finches. Environmental managers should carefully consider the ecology of Chionachne when making decisions about river flows. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
82.
83.
Edgar F. Black 《Canadian Metallurgical Quarterly》2008,22(5):303-311
A ragged array is an irregularly shaped data structure that is an extremely convenient and natural means of implementing storage schemes that exploit the symmetry and sparsity of the different stiffness matrices involved in the finite-element method. Ragged arrays have the potential for improving the programmer’s productivity as well as enhancing code maintainability. Additionally, no performance degradation was detected when ragged arrays were used; the performance of the Gauss elimination procedure, implemented in C++ using ragged arrays, was comparable to the performance of the same procedure implemented in FORTRAN using traditional data structures. 相似文献
84.
Dolan Michael P.; Black John L.; Penk Walter E.; Robinowitz Ralph; DeFord Horace A. 《Canadian Metallurgical Quarterly》1985,53(4):549
Evaluated the effectiveness of a contingency contracting intervention on reducing illicit drug use by 21 25–60 yr old male methadone maintenance patients selected on the basis of positive urinalysis results during a 60-day baseline. The intervention consisted of a 30-day contract, which stated that Ss would continue to receive a specified dosage of methadone, would not be asked to leave the program or detoxify, and would not use illicit drugs during the contract period. Illicit drug use was significantly reduced during the 30-day intervention and remained below baseline levels during a 60-day follow-up. (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
32P-postlabeling detection of DNA adducts in fish from chemically contaminated waterways 总被引:1,自引:0,他引:1
Fish were collected from sites in the chemically-contaminated Buffalo River, New York, and the Detroit River, Michigan. The sediments of these rivers have high levels of chemical contaminants, including polycyclic aromatic hydrocarbons (PAHs), and fish from these locations have high prevalences of liver cancer. To determine chemical-DNA interactions and a possible role for chemicals as a cause of the observed tumors, DNA was isolated from livers and was enzymatically digested to normal and adducted nucleotides. The DNA digests were enriched for hydrophobic, bulky adducts, either by preparative reverse phase high pressure liquid chromatography, or by selective nuclease P1 dephosphorylation of normal nucleotides. DNA-chemical adducts were then quantitated by 32P-postlabeling analysis. Regardless of the adduct enrichment procedure, the chromatograms derived from DNA of fish from polluted areas showed a diffuse, diagonal radioactive zone consisting, at least in part, of multiple overlapping discrete adduct spots. The behavior of the adducts in the diagonal radioactive zone and of their unlabeled precursors is consistent with their identification as nucleotide adducts of a variety of bulky, hydrophobic, aromatic genotoxic compounds. Analysis of bile demonstrated recent exposure to multi-ringed aromatic compounds. 相似文献
86.
A simple `floating? integrator technique is presented that is applicable to both single-ended and differential switched-capacitor circuits which employ reset cycles. This method is useful in eliminating the effects of any input offset or interstage differential or common-mode offsets in DC-coupled circuits. A monolithic circuit is demonstrated which uses this technique to achieve accurate differential integration of low-level signals in the presence of substantial differential and common-mode input offsets. 相似文献
87.
HD Kalter M Hossain G Burnham NZ Khan SK Saha MA Ali RE Black 《Canadian Metallurgical Quarterly》1999,13(1):99-113
The objective of this study was to validate retrospective caregiver interviews for diagnosing major causes of severe neonatal illness and death. A convenience sample of 149 infants aged < 28 days with one or more suspected diagnoses of interest (low birthweight/severe malnutrition, preterm birth, birth asphyxia, birth trauma, neonatal tetanus, pneumonia, meningitis, septicaemia, diarrhoea, congenital malformation or injury) was taken from patients admitted to two hospitals in Dhaka, Bangladesh. Study paediatricians performed a standardised history and physical examination and ordered laboratory and radiographic tests according to study criteria. With a median interval of 64.5 days after death or hospital discharge, caregivers of 118 (79%) infants were interviewed about their child's illness. Using reference diagnoses based on predefined clinical and laboratory criteria, the sensitivity and specificity of particular combinations of signs (algorithms) reported by the caregivers were ascertained. Sufficient numbers of children with five reference standard diagnoses were studied to validate caregiver reports. Algorithms with sensitivity and specificity > 80% were identified for neonatal tetanus, low birthweight/severe malnutrition and preterm delivery. Algorithms with specificities > 80% for birth asphyxia and pneumonia had sensitivities < 70%, or alternatively had high sensitivity with lower specificity. In settings with limited access to medical care, retrospective caregiver interviews provide a valid means of diagnosing several of the most common causes of severe neonatal illness and death. 相似文献
88.
DA Black 《Canadian Metallurgical Quarterly》1997,11(4):344-346
RT-PCR method was used to detect the expression level of multi-drug resistance gene (MDR1) and multi-drug resistance associated protein (MRP) in patients with malignant blood disease, including 19 cases of acute leukemia and 6 cases of multiple myeloma. The results showed: expression level of MDR1 in patients with known clinical drug resistance elevated obviously and was significantly associated with clinical drug resistance (r = 0.612, P < 0.01), which indicated that expression of MDR1 was the main mechanism of clinical drug resistance. There is no obvious relationship between expression level of MDR1 and MRP (r = 0.035, P > 0.05). 相似文献
89.
Refactoring Tools: Fitness for Purpose 总被引:1,自引:0,他引:1
Refactoring tools can improve the speed and accuracy with which developers create and maintain software—but only if they are used. In practice, tools are not used as much as they could be; this seems to be because sometimes they do not align with the refactoring tactic preferred by most programmers, a tactic the authors call "floss refactoring." They propose five principles that characterize successful floss-refactoring tools—principles that can help programmers to choose the most appropriate refactoring tools and also help toolsmiths to design tools that fit the programmer's purpose. 相似文献
90.
Carolynn Reference to Black Akintola Reference to Akintoye Eamon Reference to Fitzgerald 《International Journal of Project Management》2000,18(6):423
Partnering is increasingly being used on construction projects. Partnering involves the parties to a construction project working together in an environment of trust and openness to realise the project efficiently and without conflict. Using a UK-wide postal questionnaire survey, the opinions of different types of organisation — consultants, contractors, and clients were assessed in relation to the success factors and benefits of partnering. The study shows that UK contractors and clients are more positive about partnering than consultants. The research also indicates that certain requirements must be met if partnering is to succeed. In particular, trust, communication, commitment, a clear understanding of roles, consistency and a flexible attitude are necessary. It is recognised that nothing will change without considerable effort from all parties. Respondents believe that partnering can bring significant benefits, including fewer adversarial relationships and increased end-customer satisfaction, to the construction industry if all parties involved in a project strive for its success. 相似文献