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81.
Balbino García-Criado Antonia García-Ciudad M Esther Prez-Corona 《Journal of the science of food and agriculture》1991,57(4):507-515
Near infrared reflectance spectroscopy (NIRS) was evaluated as a method to predict the botanical composition of seminatural grassland in ‘dehesa’ systems. Samples of herbaceous biomass were harvested over four consecutive years, determining in each—by manual separation—the proportion by weight of the following taxonomic groups: grasses, legumes and the rest of the families in a single block (‘others’). After reconstructing the natural samples they were analysed by NIRS. One set of samples (calibration set) was selected for the development of the equations, assaying different mathematical treatments (log l/R, first derivative and second derivative). The ranges of coefficients of multiple determination and standard errors of calibration, respectively, for the various components were: grasses, 0.86 to 0.92 and 6.66 to 9.14; legumes, 0.77 to 0.81 and 6.82 to 7.43; and ‘others’, 0.85 to 0.88 and 8.17 to 9.54. The remaining samples not included in the development of the NIRS equations (prediction set) were used for the purposes of validating the best equations. Standard errors of performance were: grasses, 6.12; legumes, 7.56 and ‘others’, 7.70. 相似文献
82.
The literature suggests that seizure disorders are associated with an increased likelihood of intellectual problems, prompting researchers to investigate risk factors of cognitive impairment in epileptic patients. This study examined the contribution of certain variables (age of seizure onset, duration, etiology, seizure location and laterality, sex, handedness, and cerebral speech pattern) to cognitive outcome in patients with medically refractory seizures. Seizure location (temporal or extratemporal), age of onset of seizures, and handedness proved to be the best indicators of general intellectual ability. There was a relatively diverse pattern of relationships when neuropsychological tests of language, visuospatial ability, and memory were considered individually. However, a factor analytic approach revealed a simpler pattern in which location of dysfunction, age at seizure onset, hand preference, cerebral speech dominance, and gender were relevant and independent indicators of verbal and nonverbal ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
ES Harmelin RN Holcombe JP Goggin J Carbonell T Wellens 《Canadian Metallurgical Quarterly》1998,37(6):540-545
BACKGROUND: Ossification of the posterior longitudinal ligament (OPLL) may cause neuropathic bladder dysfunction due to spinal cord involvement. OPLL, unlike a traumatic spinal cord lesion, progresses insidiously and sometimes affects longer cord segments. As the manifestation of bladder dysfunction may depend on the development of OPLL, we studied the relationship between bladder function and roentgenographic changes in the spinal canals of OPLL patients. PATIENTS AND METHODS: Eighteen surgical candidates (11 males and 7 females, 34 to 85 years old) were studied urodynamically. Sixteen underwent CO2-filling cystometry, uroflowmetry and measurement of their residual urine volume. Cystometry was omitted in the remaining 2 patients. The vertical extent of OPLL and the degree of stenosis in the spinal canal was estimated by x-ray films and CT. RESULTS: The cystometric study revealed detrusor hyperreflexia in 2 patients and areflexic or underactive detrusors in 5 patients. Intermittent flows or considerable amounts of residual urine were also observed in the arefilexia/underactive group. Uroflowmetry showed a normal flow with little residual urine in both patients in whom cystometry was omitted. Bladder sensation was maintained in all patients. The occurrence of abnormal detrusor activity had no relationship to the degree of canal stenosis, while the occurrence of an areflexic or underactive detrusor correlated with the vertical extent of OPLL. CONCLUSION: Although detrusor hyperreflexia is common in an upper spinal cord lesion, attention should also be paid to the development of detrusor underactivity in patients with a wide vertical extent of OPLL. 相似文献
84.
Esther K. Nemethy John W. Otvos Melvin Calvin 《Journal of the American Oil Chemists' Society》1979,56(12):957-960
Chemical analyses have been made of the heptane extractable material ofEuphorbia lathyris, a plant which has been proposed as an “energy farm” candidate. The heptane extract is 4–5% of the dry plant weight and has
a heat value of ≈18×103 BTU/Ib. This reduced photosynthetic material consists almost entirely of polycyclic triterpenoids. 相似文献
85.
Grid Data Management: Open Problems and New Issues 总被引:3,自引:0,他引:3
Initially developed for the scientific community, Grid computing is now gaining much interest in important areas such as enterprise
information systems. This makes data management critical since the techniques must scale up while addressing the autonomy,
dynamicity and heterogeneity of the data sources. In this paper, we discuss the main open problems and new issues related
to Grid data management. We first recall the main principles behind data management in distributed systems and the basic techniques.
Then we make precise the requirements for Grid data management. Finally, we introduce the main techniques needed to address
these requirements. This implies revisiting distributed database techniques in major ways, in particular, using P2P techniques.
Work partially funded by ARA “Massive Data” of the French ministry of research (project Respire), the European Strep Grid4All
project, the CAPES–COFECUB Daad project and the CNPq–INRIA Gridata project. 相似文献
86.
87.
Esther Perales Francisco M. Martínez‐Verdú Valentín Viqueira Jesús Fernández‐Reche José A. Díaz Joan Uroz 《Color research and application》2009,34(4):330-336
In this work, we have studied the relationship among the colorimetric properties of different types of paper, having different finishing and grammage. Their color reproduction capability has also been analyzed by using the same printing technology (inkjet printing). On the one hand, we have plotted CIELAB data under the illuminant D50 into constant lightness and hue‐angle planes to be compared with MacAdam limits and with Pointer's real‐world surface color. On the other hand, we have calculated the volume gamut of the color solid associated to each color paper gamut. Analyzing the results, we have checked that there is not any clear relationship among the colorimetric properties of paper (for instance, CIE whiteness index, etc.) and the color gamut volume associated. However, the colorimetric parameters associated to the printed sample showed a quite good linear correlation between the minimum lightness (or the maximum blackness value) of the printed color chart and the color gamut volume. In particular, the greatest color gamut volume corresponds to the glossy papers taking into account this correlation for inkjet printing. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 330–336, 2009 相似文献
88.
Bielak Allison A. M.; Hultsch David F.; Strauss Esther; MacDonald Stuart W. S.; Hunter Michael A. 《Canadian Metallurgical Quarterly》2010,25(3):575
In this study, the authors addressed the longitudinal nature of intraindividual variability over 3 years. A sample of 304 community-dwelling older adults, initially between the ages of 64 and 92 years, completed 4 waves of annual testing on a battery of accuracy- and latency-based tests covering a wide range of cognitive complexity. Increases in response-time inconsistency on moderately and highly complex tasks were associated with increasing age, but there were significant individual differences in change across the entire sample. The time-varying covariation between cognition and inconsistency was significant across the 1-year intervals and remained stable across both time and age. On occasions when intraindividual variability was high, participants' cognitive performance was correspondingly low. The strength of the coupling relationship was greater for more fluid cognitive domains such as memory, reasoning, and processing speed than for more crystallized domains such as verbal ability. Variability based on moderately and highly complex tasks provided the strongest prediction. These results suggest that intraindividual variability is highly sensitive to even subtle changes in cognitive ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Muthuraj Esther Leena Preethi Thiripuranthagan Sivakumar Muthiahpillai Palanichami 《Catalysis communications》2010,11(10):876-879
Fe/Al-MCM-41 (Si/Al = 25, 50, 75 and 100) were synthesized. Their catalytic activity was evaluated towards benzylation of benzene with benzyl chloride in liquid phase. The catalytic activity of Fe/Al-MCM-41(25) was higher than the other catalysts. Diphenylmethane(DPM) was obtained as the major product with 100% selectivity and with 100% conversion of benzyl chloride under optimum condition. The effect of temperature and the feed ratio, on the activity of Fe/Al-MCM-41(25) and selectivity towards DPM was studied and a possible reaction mechanism was proposed. 相似文献
90.
Dodge Kenneth A.; McClaskey Cynthia L.; Feldman Esther 《Canadian Metallurgical Quarterly》1985,53(3):344
Generated and evaluated a taxonomy of the situations and tasks most likely to lead deviant children to experience social difficulties. In Study 1, elementary school teachers and clinicians were asked to notice such situations as they occurred. The outcome was a 44-item taxonomy of problematic social situations for children. This survey was administered to teachers of 45 socially rejected children (79% male) from Grades 3–5 and 39 adaptive children of the opposite sociometric criteria who were matched by sex and age to the rejected Ss. The survey was found to have high internal consistency and high test–retest reliability. Six situation types emerged as factors in analyses: Peer Group Entry, Response to Peer Provocations, Response to Failure, Response to Success, Social Expectations, and Teacher Expectations. Teachers rated the rejected group as having more problems than the adaptive group in each situation, but particularly in Response to Peer Provocations and Teacher Expectations. In Study 2, 15 items within the 6 factors were presented in a hypothetical format to 39 clinic-referred rejected aggressive children (77% males) from Grades 3–5 and 34 adaptive children selected by opposite criteria and matched by sex and age to the rejected aggressive Ss, who were asked to role play their responses. The items, in particular the provocation items, again differentiated the 2 groups. Sex and age differences were also found. The usefulness of this taxonomy in a 3-step model of clinical assessment is proposed. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献