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401.
402.
We have studied the effect of flap parameters on fluid rectification in a microfluidic diode. We use Navier-Stokes equations and arbitrary Lagrangian-Eulerian formulation to obtain dynamics of fluid flow and motion of the flap. The flap opens during forward flow and seals against a stopper during reverse flow. This allows flow in the forward direction and prevents it in the reverse direction. The rectifier is fluidic analog to a semiconductor diode in function because it rectifies fluid flow. Velocity-pressure (V-P) curves analog to the current-voltage (I-V) curves of the electronic diode has been obtained. The effect of the flap parameters, such as length, thickness, and Young's modulus has been found out. The transient response of the flap and fluid flow under oscillating pressure driven flow has also been obtained. 相似文献
403.
Goswami B Singh B Chawla R Gupta VK Mallika V 《Indian journal of clinical biochemistry : IJCB》2010,25(4):376-379
Laboratory analytical turnaround time is a reliable indicator of laboratory effectiveness. Our study aimed to evaluate laboratory
analytical turnaround time in our laboratory and appraise the contribution of the different phases of analysis towards the
same. The turn around time (TAT) for all the samples (both routine and emergency) for the outpatient and hospitalized patients
were evaluated for one year. TAT was calculated from sample reception to report dispatch. The average TAT for the clinical
biochemistry samples was 5.5 h for routine inpatient samples while the TAT for the outpatient samples was 24 h. The turnaround
time for stat samples was 1 h. Pre- and Post-analytical phases were found to contribute approximately 75% to the total TAT.
The TAT demonstrates the need for improvement in the pre- and post-analytical periods. We need to tread the middle path to
perform optimally according to clinician expectations. 相似文献
404.
405.
Brajesh Singh Smiti Singh J K Bhatia Rajan Kapoor Kapil Bhatia 《Indian journal of clinical biochemistry : IJCB》2023,38(2):193
The interrelationship between matrix degradation, oxidative stress, inflammation and trace elements can be speculated in COVID-19. The objective of the study was to evaluate the oxidative stress, inflammation and matrix degradation markers and trace elements in COVID-19 positive patients. A group of confirmed severe COVID-19 positive patients (n = 30) along with COVID-19 negative patients (n = 30) with similar symptoms were included. Both group of patients were assessed for oxidative stress markers, inflammatory cytokines, matrix metalloproteinase (MMP)s and their inhibitors along with trace elements in blood. All the data were subjected to univariate as well as multivariate analysis including PCA, PLS-DA, OPLS-DA. Diagnostic accuracy was tested by ROC curve analysis. Further relationship with Neutrophil/ lymphocyte (N/L) ratio was established if any. Increased oxidative stress, inflammation and matrix degradation is evidenced by significant rise in oxidative markers, inflammatory cytokines and MMP9/TIMP-1 ratio. Decreased Cu/Zn ratio is also observed in COVID-19 positive patients. Multivariate analysis identified SOD, Cu/Zn ratio, IL-6 and TOS, as effective discriminant among the two groups of patients. Further, accuracy was confirmed by ROC curves. Neutrophil/ lymphocyte (N/L) ratio, shows significant negative association with SOD (r= -0.75, p < 0.005) and Cu/Zn ratio (r = -0.88, p < 0.005). These data suggest the attributes of these biomarkers in disease severity. The potential use of these blood-based laboratory markers in disease prognosis seems promising and warrants further attention. Given by the symptoms and severity of the disease, it will be promising to monitor Cu/Zn ratio along with other prognostic indicators. 相似文献
406.
Yu Yang Shenglan Chen Xiaoxuan Wu Li Peng Juan I Vílchez Richa Kaushal Xiaomin Liu Sunil K Singh Danxia He Fengtong Yuan Suhui Lv Rafael J L Morcillo Wei Wang Weichang Huang Mingguang Lei Jian-Kang Zhu Paul W Par Huiming Zhang 《国家科学评论(英文版)》2022,9(8)
Unlike microbe-associated molecular patterns (MAMPs) that are readily targeted by host immunity, microbial non-pathogenic factors (NPFs) appear negligible as they do not elicit defense. Little is known about whether and how NPFs may be monitored by hosts to control compatibility. Herein, a forward genetic screening isolated an Arabidopsis mutant with a loss of plant-rhizobacteria mutualism, leading to the disclosure of a plant latent defense response (LDR) to NPFs. The activation of LDR in the mutant, named rol1 for regulator of LDR 1, is triggered by several non-pathogenic volatile organic compounds and antagonizes plant compatibility with the beneficial bacterium Bacillus amyloliquefaciens GB03. The activation of LDR in rol1 is mediated through the prokaryotic pathway of chloroplastic lipid biosynthesis. The rol1 root microbiome showed a reduced proportion of the Bacillaceae family. We propose that, parallel to the forefront immunity to MAMPs, LDR to certain NPFs provides a hidden layer of defense for controlling compatibility with commensal or beneficial microbes. 相似文献
407.
This paper explores methods by which the Individualized Education Plan (IEP) development process can be improved through the use of systems-based thinking, specifically through the use of Gittell’s (2016) Relational Coordination Model. IEP development meetings have been described as meaningless rituals where parents often leave feeling ostracized from their child’s academic experience due to an overemphasis on academic jargon and procedure (Rock, 2000; Salas, 2004). Systems-based thinking would encourage administrators to empower parents as equal partners in the IEP development process, as originally intended by the Individuals with Disabilities Education Act of 1994. Furthermore, using Relational Coordination as a framework for work-group structure would also allow school officials to create meaningful relationships with parents based on trust, thus resulting in a more positive IEP development experience and more robust educational plans. 相似文献
408.
409.
B. K. Singh 《开放教育研究》2006,12(2):53-57
After a brief analysis of the concept of quality in open and distance education, information technology for quality assurance and Indian initiative for quality improvement, the paper examines the quality assurance measures at Kota Open University under the following areas : planning academic programmes ; developing academic programmes ; producing learning materials ; implementing programmes ; reviewing courses/programmes ; and ing human resources. 相似文献
410.