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241.
The deposition of silicon nitride thin films by the reactive sputtering of elemental silicon in a nitrogen/argon plasma has been investigated. The composition of the thin films has been examined using infra-red reflectance, X-ray photoelectron and Auger electron spectroscopies and spark source mass spectrometry. Oxygen has been found to be a major contaminant in these sputter deposited films, the oxygen concentration depending on the ambient gas pressure. The use of the silicon oxy-nitride films as annealing encapsulants for the activation of silicon ion implanted semi-insulating gallium arsenide has also been investigated. 相似文献
242.
Mekhala DK Vithana Zora Singh Stuart K Johnson 《Journal of the science of food and agriculture》2019,99(8):3740-3751
There is a demand for feasible methodologies that can increase/maintain the levels of health-promoting phytochemicals in horticultural produce, due to strong evidence that these compounds can reduce risk of chronic diseases. Mango (Mangifera indica L.), ranks fifth among the most cultivated fruit crops in the world, is naturally rich in phytochemicals such as lupeol, mangiferin and phenolic acids (e.g. gallic acid, chlorogenic acid and vanillic acid). Yet, there is still much scope for up-regulating the levels of these compounds in mango fruit through manipulation of different preharvest and postharvest practices that affect their biosynthesis and degradation. The process of ripening, harvest maturity, physical and chemical elicitor treatments such as low temperature stress, methyl jasmonate (MeJA), salicylic acid (SA) and nitric oxide (NO) and the availability of enzyme cofactors (Mg2+, Mn2+ and Fe2+) required in terpenoid biosynthesis were identified as potential determinants of the concentration of health-promoting compounds in mango fruit. The effectiveness of these preharvest and postharvest approaches in regulating the levels of lupeol, mangiferin and phenolic acids in the pulp and peel of mango fruit will be discussed. In general spray application of 0.2% iron(II) sulphate (FeSO4) 30 days before harvest, harvest at sprung stage, storage of mature green fruit at 5 °C for 12 days prior to ripening, fumigation of mature green fruit with 10−5 mol L−1 and/or 10−4 mol L−1 MeJA for 24 h or 20 and/or 40 µL L−1 NO for 2 h upregulate the levels of lupeol, mangiferin and phenolic acids in pulp and peel of ripe mango fruit. © 2019 Society of Chemical Industry 相似文献
243.
The assessment of anger has received increased attention because of growing evidence that anger and hostility are related to heart disease. Research on anger assessment has also been stimulated by the development of psychometric measures for evaluating different facets of anger, such as the State-Trait Anger Expression Inventory (STAXI). In this study, factor analyses of the responses of a large sample of university students to the 44 STAXI items identified 7 factors. Of these, the first 6 factors closely corresponded with the 6 STAXI scales and subscales: State Anger (S-Anger); Trait Anger Temperament and Reaction; and Anger-In, Anger-Out, and Anger-Control. All 10 STAXI S-Anger items had salient loadings on the 1st factor for both sexes; the 7th factor also consisted primarily of S-Anger items. Factor analyses of responses to the 10 S-Anger items clearly confirmed two S-Anger factors for both sexes: Feeling Angry (e.g., "I am furious") and Feel Like Expressing Anger (e.g., "I feel like hitting someone"). 相似文献
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OBJECTIVE: The purpose of this prospective, observational study was to examine the relationship of clinical examination, plain radiograph (XR), triple-phase bone scan (TPBS), and magnetic resonance imaging (MRI) in the investigation of patients presenting with acute shin splints. METHODS: 23 subjects with exercise induced lower leg pain and diffuse tibial tenderness of less than 3 months' duration were recruited. Subjects were excluded if there was clinical evidence of compartment syndrome, muscle hernia, or stress fracture. Each subject underwent XR, TPBS, and MRI within 2 wk of physical examination. Four asymptomatic controls underwent TPBS and MRI. Clinical findings, XR, TPBS, and MRI findings were independently recorded using a consistent template and subsequently analyzed. A single consensus lesion was chosen that provided the greatest overlap and highest grade to allow comparison of clinical and imaging findings. Sensitivity and specificity were calculated from data relating to clinical findings and diagnostic imaging. RESULTS: Eighteen subjects had bilateral symptoms and five unilateral with a mean duration of symptom of 5.4 wk (+/- 3.5). Of 41 symptomatic lower legs, there were TPBS abnormalities in 36 and MRI findings in 34. Analysis of clinical findings to TPBS and MRI demonstrated a sensitivity and specificity of 84%, 33% and 79%, 33%, respectively. Assuming TPBS as the "gold-standard," MRI findings demonstrated a sensitivity of 95% and specificity of 67%. There was poor agreement between the grading of TPBS and MRI (k = 0.3). In the 5/46 asymptomatic limbs, 3/5 demonstrated uptake on bone scan and 4/5 signal change with MRI. Imaging abnormalities were similarly seen in the four control patients. CONCLUSIONS: MRI may be used rather than TPBS and radiographs for evaluating acute tibial pain in athletes where avoidance of radiation exposure is desirable. Similar sensitivity and specificity may be expected from both investigations; however, in the light of abnormal TPBS and MRI findings in control and asymptomatic limbs, we recommend further studies be performed to define the extent of nonpathological TPBS and MRI changes. 相似文献
246.
B Lozoff NK Klein EC Nelson DK McClish M Manuel ME Chacon 《Canadian Metallurgical Quarterly》1998,69(1):24-36
This study tested the hypothesis that infants with iron-deficiency anemia show behaviors, such as increased proximity to caregivers, increased wariness or hesitance, and decreased activity, that could contribute to "functional isolation." The behavior of 52 Costa Rican 12- to 23-month-old infants with iron-deficiency anemia was contrasted with that of 139 comparison group infants with better iron status during free play and mental and motor testing and in the home. Infants with iron-deficiency anemia maintained closer contact with caregivers; showed less pleasure and delight; were more wary, hesitant, and easily tired; made fewer attempts at test items; were less attentive to instructions and demonstrations; and were less playful. Adult behavior also differed. The results indicate that iron-deficiency anemia in infancy is associated with alterations in affect and activity, suggesting that functional isolation is a useful framework for understanding poorer developmental outcome in iron-deficiency anemia, the world's most common single nutrient deficiency. 相似文献
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248.
DK Raap F Garcia NA Muma WA Wolf G Battaglia LD van de Kar 《Canadian Metallurgical Quarterly》1999,288(2):561-567
Long-term exposure to fluoxetine produces a desensitization of hypothalamic postsynaptic 5-hydroxytryptamine (5-HT)1A receptors, indicated by a substantial inhibition of the 5-HT1A receptor-mediated stimulation of oxytocin and adrenocorticotropic hormone (ACTH) secretion. The present study investigated the time course and mechanism of this desensitization after discontinuation of fluoxetine administration. Male rats were injected with saline or fluoxetine (10 mg/kg/day, i.p.) for 14 days and were challenged with a 5-HT1A agonist, [8-hydroxy-2-(dipropylamino)tetralin (8-OH-DPAT) 50 microg/kg, s.c.] 2, 4, 7, 14, 28, or 60 days post-treatment. In control animals, 8-OH-DPAT significantly increased (approximately 15-fold) plasma levels of oxytocin and ACTH. At 2 days post-treatment, oxytocin and ACTH responses to 8-OH-DPAT were reduced by 74% and 68%, respectively. During further withdrawal from fluoxetine, there was a gradual increase in the oxytocin response toward control levels. However, even 60 days after discontinuation of fluoxetine, the oxytocin response was still significantly reduced by 26% compared with controls. In contrast, the suppressed ACTH response to 8-OH-DPAT (a less-sensitive indicator of desensitization) gradually returned to control levels by day 14 of withdrawal from fluoxetine. Interestingly, the sustained reductions in the hormone responses occurred in the absence of reductions in Gz or Gi protein levels in the hypothalamus. Furthermore, this desensitization was sustained in the absence of detectable levels of fluoxetine and norfluoxetine in plasma and brain tissue. These findings suggest that the sustained desensitization of hypothalamic 5-HT1A receptor systems, observed during fluoxetine withdrawal, may be due to altered interactions among the protein components of the 5-HT1A receptor system, rather than their absolute levels. 相似文献
249.
OBJECTIVE: To determine whether strabismus surgery during active thyroid ophthalmopathy is beneficial for selected patients. DESIGN: Case series. PARTICIPANTS: Eight patients with severe restrictive strabismus due to thyroid ophthalmopathy underwent early strabismus surgery and were followed for a minimum of 16 months after their initial surgery. INTERVENTION: All eight patients underwent strabismus surgery while their thyroid ophthalmopathy was evolving. MAIN OUTCOME MEASURES: Success was determined by the ability to fuse in the primary position at distance and near without an abnormal head position, and the absence of vision-threatening complications related to strabismus surgery. RESULTS: All eight patients achieved successful long-term alignment. Four patients (50%) required more than one operation. CONCLUSIONS: Strabismus surgery during active thyroid ophthalmopathy can result in long-term stable alignment and may be a useful alternative in selected patients with marked disability due to thyroid ophthalmopathy. 相似文献
250.