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Alam  Ashraful  Hariyanto  Bambang  Ullah  Hayat  Salin  Krishna R.  Datta  Avishek 《SILICON》2021,13(9):3153-3162
Silicon - Silicon (Si) plays an important role in mitigating adverse effects of various biotic and abiotic stresses including drought. Polyhouse experiment was conducted to evaluate the effects of...  相似文献   
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We report a study of the inhomogeneities in thin helium films due to the van der Waals potential by a resonant acoustical technique. The van der Waals constant between helium and quartz is estimated to be =65±5 K (layer)3; the model leads to a solid helium layer on the substrate of the order ofH=2.2a 0 . A comparison is made with data extracted from interferometric acoustical methods and third-sound type experiments.Associated with the Centre National de la Recherche Scientifique.  相似文献   
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Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 5, pp. 8–9, May, 1991.  相似文献   
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We investigated whether the surprisingly good memory performance of alcoholics may result from simple memory performance being spared while performance in complex memory tasks is impaired. Simple word span was contrasted with a complex word span task involving concurrent monitoring and re-organisation of items for recall. To control for disruption of rehearsal in the complex word span task, performance on two additional tasks with disrupted rehearsal but no additional processing components was studied. As hypothesised, the alcoholics showed a deficit in the complex but not the simple word span task. They were also impaired, compared to controls, on both tasks with disrupted rehearsal. The difference between groups remained in the complex span task when scores in simple span and either of the two other tasks were used as covariates. Thus, both executive processes necessary for coping with disrupted rehearsal and additional processes scheduling processing and storage in a complex task may play a role in accounting for working memory deficits found in alcoholics.  相似文献   
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The present study examined the effects of prolonged L-DOPA treatment (6 months) alone or in combination with unilateral 6-hydroxydopamine-induced lesion of the mesostriatal dopaminergic pathway on substance P and enkephalin mRNA expression in the rat neostriatum. This was done by means of quantitative in situ hybridization histochemistry. As reported previously, the unilateral dopaminergic lesion induced a significant and homogeneous decrease in striatal substance P mRNA expression and a marked increase in enkephalin mRNA expression in the ipsilateral neostriatum which was more pronounced in the dorsolateral than ventromedial part of the structure. Long-term L-DOPA treatment alone had no significant effects on the two striatal peptide mRNA levels. The chronic L-DOPA treatment in 6-hydroxydopamine-lesioned rats was found to partially reverse the lesion-induced down-regulation of substance P mRNA expression, without significantly affect the up-regulation of enkephalin when considering the neostriatum as a whole. Topographical analysis revealed that long-term L-DOPA treatment reversed, in fact, both post-lesional enkephalin and substance P responses to 6-hydroxydopamine lesion, in the ventromedial neostriatum, without significantly modified these peptide responses in the dorsolateral neostriatum. These findings provide new evidence that prolonged L-DOPA treatment differentially affects the post-lesional peptide responses in the ventromedial and dorsolateral parts of the neostriatum, suggesting regional cellular mechanisms in the neostriatum underlying the benefit and/or side-effects of L-DOPA treatment in parkinsonian patients.  相似文献   
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A previous study showed that classical building-related symptoms (BRS) were related to indoor dust and microbial toxicity via boar sperm motility assay, a sensitive method for measuring mitochondrial toxicity. In this cross-sectional study, we analyzed whether teachers’ most common work-related non-literature-known BRS (nBRS) were also associated with dust or microbial toxicity. Teachers from 15 schools in Finland completed a questionnaire evaluating 20 nBRS including general, eye, respiratory, hearing, sleep, and mental symptoms. Boar sperm motility assay was used to measure the toxicity of extracts from wiped dust and microbial fallout samples collected from teachers’ classrooms. 231 teachers answered a questionnaire and their classroom toxicity data were recorded. A negative binomial mixed model showed that teachers’ work-related nBRS were 2.9-fold (95% CI: 1.2-7.3) higher in classrooms with highly toxic dust samples compared to classrooms with non-toxic dust samples (p = 0.024). The RR of work-related nBRS was 1.8 (95% CI: 1.1-2.9) for toxic microbial samples (p = 0.022). Teachers’ BRS appeared to be broader than reported in the literature, and the work-related nBRS were associated with toxic dusts and microbes in classrooms.  相似文献   
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In this technical note, a liquid-liquid extraction technique was performed using pneumatic liquid recirculation on a centrifugal microfluidic device. Non-contact pneumatic pumping enabled a multi-cycle liquid-liquid extraction process using aqueous iodine in a potassium iodide solution and hexadecane while requiring a minimal amount of space on the device. The extraction process was completely automated on the device following sample introduction and required only 50 s for each extraction cycle. The pumping rate achieved during liquid recirculation was 120 ± 10 μL/min. A recycling process such as the one demonstrated would be difficult to implement in a conventional centrifugal microfluidic system.  相似文献   
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It is of considerable importance to be able to distinguish metallic species because their toxicity depends on their chemical form. Therefore, the analysis of environmental samples can be enhanced by the combination of high-performance thin-layer chromatography (HPTLC) with laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). In this study, Cr (3+) and Cr (6+) were separated on silica gel HPTLC plates using aqueous mobile phases. Separation was achieved in seconds with retardation factors ( R f ) of 0 and 1 for Cr (3+) and Cr (6+), respectively. LA was used to volatilize the chromium species directly from the chromatographic material prior to ICPMS detection. A linear calibration was obtained, and detection limits (3sigma) of 6 ng for Cr (6+) and 0.4 ng for Cr (3+) were achieved with precision ranging from 3 to 40% at the 95% confidence level. The silicon present in the stationary phase was used as an internal standard. This procedure allows for a rapid separation and quantification, requires only 0.5 muL of sample, and lower detection limits can be achieved through preconcentration.  相似文献   
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