prolonged reaction time
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2021 ◽  
Vol 11 (12) ◽  
pp. 157-161
Author(s):  
Roopa Desai ◽  
Jagruti v ◽  
Shilpa Khandare

According to scientific literature, evidence of relationship exists between dexterity and age. With increasing age, the performances get slower, less smooth, less coordinated and less controlled. Lesser the reaction time, better is the achievement seen sports, music, driving, academics and also in day-to-day activities. We can always predict reacting abilities of an individual based on his reaction time. In case of surgeons, this helps us to identify the surgeons with prolonged reaction time and identify the cause. Some studies suggest that there is direct relationship that exists between muscle strength and increased age. Aim: This study aimed in assessing the association of age with hand grip strength, pinch strength and reaction time in Gynaecologists and Obstetricians. Methods: This study involved 30 Gynaecologists and Obstetricians. Hand grip strength, Pinch Grip Strength and Reaction time were assessed on both dominant and non- dominant hand. Results: The result showed positive correlation of age with hand grip strength and pinch strength and negative correlation of age with reaction in Gynaecologists and Obstetricians. Conclusion: There is low association of age with hand grip strength and pinch strength, there is reduction in reaction time as age increases in Gynaecologists and Obstetricians. Key words: Age, Hand grip strength, Pinch Grip Strength, Reaction time, Gynecologists.


Author(s):  
Yun Wang ◽  
Jianhua Mao ◽  
Li Li ◽  
Bing Xiao ◽  
Zheng Ruan ◽  
...  

AbstractPlatelet-targeted FVIII gene therapy can efficiently recover bleeding phenotype for hemophilia A (HA), yet characteristics of thrombus formation with this ectopic expression of factor VIII (FVIII) in platelets remain unclear. Here, we generated 2bF8trans mice restrictively expressing human B-domain–deleted FVIII (hBDD FVIII) in platelets on a hemophilic (FVIIInull) mice background. The results showed no statistical difference in clot strength and stability between wild-type (WT) and 2bF8trans mice, but with a prolonged reaction time (R-time), by thromboelastography. Fluid dynamics analysis showed that at the shear rates of 500 to 1,500 s−1, where physiological hemostasis often develops, the thrombi formed in 2bF8trans mice were more stable than those in FVIIInull mice, while at high pathological shear rates (2,500 s−1), mimicking atherosclerosis, thrombus size and fibrin deposition in 2bF8trans mice were less than those in WT mice. Thrombus morphology analysis showed that there was a locally concentrated deposition of fibrin in thrombus at the injured site and fibrin co-localized with activated platelets in 2bF8trans mice. Moreover, a higher ratio of fibrin to platelets was found in thrombus from 2bF8trans mice following laser-induced injury in cremaster arterioles, which might be the underlying mechanism of thrombus stability in 2bF8trans mice at physiological arterial circumstance. These observations suggest that specific morphological features of the thrombi might contribute to the efficacy and safety of platelet-targeted FVIII gene therapy for HA.


2021 ◽  
Vol 118 (23) ◽  
pp. e2012649118
Author(s):  
Guiji Liu ◽  
Michelle Lee ◽  
Soonho Kwon ◽  
Guosong Zeng ◽  
Johanna Eichhorn ◽  
...  

We elucidate the role of subsurface oxygen on the production of C2 products from CO2 reduction over Cu electrocatalysts using the newly developed grand canonical potential kinetics density functional theory method, which predicts that the rate of C2 production on pure Cu with no O is ∼500 times slower than H2 evolution. In contrast, starting with Cu2O, the rate of C2 production is >5,000 times faster than pure Cu(111) and comparable to H2 production. To validate these predictions experimentally, we combined time-dependent product detection with multiple characterization techniques to show that ethylene production decreases substantially with time and that a sufficiently prolonged reaction time (up to 20 h) leads only to H2 evolution with ethylene production ∼1,000 times slower, in agreement with theory. This result shows that maintaining substantial subsurface oxygen is essential for long-term C2 production with Cu catalysts.


BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Tao Zhang ◽  
Jiapei Yang ◽  
Zhongxia Zhou ◽  
Zhipeng Fu ◽  
Srinivasulu Cherukupalli ◽  
...  

Abstract Background Rilpivirine (RPV) was approved by the U.S. FDA (Food and Drug Administration) in 2011 to treat individuals infected with human immunodeficiency virus 1 (HIV-1). Significantly, rilpivirine is three fold more potent than etravirine. Once-daily, it is used with a low oral dose (25 mg/tablet), decreasing the drug administration and bringing a better choice to the patients. However, there are many shortcomings in the existing synthesis route of RPV, such as the high cost, prolonged reaction time and low yield (18.5%). Results This article describes our efforts to develop an efficient and practical microwave-promoted method to synthesize rilpivirine using less toxic organic reagents and low boiling solvents. The last step's reaction time decreased from 69 h to 90 min through this optimized synthetic procedure, and the overall yield improved from 18.5 to 21%. In addition, the yield of intermediate 3 increased from 52 to 62% compared to the original patent. Conclusion Overall, through a series of process optimization, we have developed a practical synthesis method of rilpivirine, which is easy to scale with higher yield and shorter reaction time.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1578
Author(s):  
Renata Kołodziejska ◽  
Renata Studzińska ◽  
Agnieszka Tafelska-Kaczmarek ◽  
Hanna Pawluk ◽  
Dominika Mlicka ◽  
...  

In this study, we examined the Aureobasidium pullulans strains DSM 14940 and DSM 14941 included in the Blossom Protect™ agent to be used in the bioreduction reaction of a symmetrical dicarbonyl compound. Both chiral 2-hydroxy-1,2-diphenylethanone antipodes were obtained with a high enantiomeric purity. Mild conditions (phosphate buffer [pH 7.0, 7.2], 30 °C) were successfully employed in the synthesis of (S)-benzoin using two different methodologies: benzyl desymmetrization and rac-benzoin deracemization. Bioreduction carried out with higher reagent concentrations, lower pH values and prolonged reaction time, and in the presence of additives, enabled enrichment of the reaction mixture with (R)-benzoin. The described procedure is a potentially useful tool in the synthesis of chiral building blocks with a defined configuration in a simple and economical process with a lower environmental impact, enabling one-pot biotransformation.


2021 ◽  
Author(s):  
Tao Zhang ◽  
Jiapei Yang ◽  
Zhongxia Zhou ◽  
Zhipeng Fu ◽  
Srinivasulu Cherukupalli ◽  
...  

Abstract Background: Rilpivirine (RPV) is a potent and selective non-nucleoside reverse transcriptase inhibitor (NNRTI) of the diarylpyrimidine family with unique antiviral activity, low toxicity and high specificity. It is approved by the U.S. FDA (Food and Drug Administration) in 2011 to treat individuals infected with human immunodeficiency virus 1 (HIV-1). Significantly, rilpivirine is 3-fold more potent than etravirine. Once-daily, it is used with a low oral dose (25mg/tablet), decreasing the drug administration and bringing the better choice to the patients. However, there are many shortcomings in the existing synthesis route of RPV, such as the high cost, prolonged reaction time and low yield (18.5%).Results: This article describes our efforts to develop an efficient and practical microwave-promoted method to synthesize rilpivirine using less toxic organic reagents and low boiling solvents. The last step's reaction time decreased from 69 h to 90 min through this optimized synthetic procedure, and the overall yield improved from 18.5% to 21%. In addition, the yield of intermediate 3 increased from 52% to 62% compared to the original patent.Conclusion: Overall, through a series of process optimization, we have developed a practical synthesis method of rilpivirine, which is easy to scale with higher yield and shorter reaction time.


Processes ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 655
Author(s):  
Xiaofei Sheng ◽  
Yajuan Cheng ◽  
Yingming Yao ◽  
Zhe Zhao

The deposition parameters involved in chemical bath deposition were optimized by a response surface methodology to synthesize upright ZnO rod arrays with large diameters. The effects of the factors on the preferential orientation, aspect ratio, and diameter were determined systematically and efficiently. The results demonstrated that an increased concentration, elevated reaction temperature, prolonged reaction time, and reduced molar ratio of Zn2+ to tri-sodium citrate could increase the diameter and promote the preferential oriented growth along the [002] direction. With the optimized parameters, the ZnO rods were grown almost perfectly vertically with the texture coefficient of 99.62. In the meanwhile, the largest diameter could reach 1.77 μm. The obtained rods were merged together on this condition, and a dense ZnO thin film was formed.


2020 ◽  
Vol 35 (1) ◽  
pp. 18-24
Author(s):  
Hailong Li ◽  
Chao Du ◽  
Shujuan Ge ◽  
Mengru Liu

AbstractThis study aimed to investigate the oxalate formation mechanism during chlorine dioxide ({\mathrm{ClO}_{2}}) bleaching of bamboo kraft pulp, and thus explore favourable {\mathrm{ClO}_{2}} bleaching conditions to better control oxalate formation. The amount of oxalate formed varied linearly with {\mathrm{ClO}_{2}} dosage within the whole research range, while it rose exponentially within the first 90 mins of pulp bleaching. Then the actual bleaching process was simulated by reacting {\mathrm{ClO}_{2}} with three representative lignin model compounds and comparatively studied. The rule of oxalate formation in the simulated reaction system was identical to that in pulp bleaching by {\mathrm{ClO}_{2}}, except for oxalate production by veratraldehyde with prolonged reaction time. Under identical conditions, vanillin formed the highest amount of oxalate, while veratraldehyde formed the least. Furthermore, the amount of oxalate formed increased by 19.59 mg/kg when the kappa number of the delignified pulp was reduced by one unit. Considering the satisfactory pulp brightness and decreased oxalate formation, the recommended conditions for {\mathrm{ClO}_{2}} bleaching of bamboo kraft pulp were a {\mathrm{ClO}_{2}} dosage of 4 %, 60 °C and 70 mins.


2020 ◽  
Vol 22 (35) ◽  
pp. 19769-19778
Author(s):  
Mustafa İlhan ◽  
İlker Çetin Keskin

In this work, Dy3+-doped SrNb2O6 phosphors were fabricated by the molten salt process, which avoids high sintering temperatures, prolonged reaction time and poor compositional homogeneity.


Catalysts ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 5 ◽  
Author(s):  
Chengyu Yang ◽  
Weiming Fan ◽  
Ruijie Zhang ◽  
Jiping Shi ◽  
Zorica Knežević-Jugović ◽  
...  

α-Arbutin (4-hydroquinone-α-D-glucopyranoside), an effective skin-lightening agent due to its considerable inhibitory effect on human tyrosinase activity, is widely used in the pharmaceutical and cosmetic industries. Recently, α-arbutin was prepared through transglucosylation of hydroquinone using microbial glycosyltransferases as catalysts. However, the low yield and prolonged reaction time of the biotransformation process of α-arbutin production limited its industrial application. In this work, an amylosucrase (ASase) from Xanthomonas campestris pv. campestris str. ATCC 33913 (XcAS) was expressed efficiently in Escherichia coli JM109. The catalytic property of the purified XcAS for the synthesis of α-arbutin was tested. The recombinant strain was applied for highly efficient synthesis of α-arbutin using sucrose and hydroquinone as glucosyl donor and acceptor, respectively. By optimizing the biotransformation conditions and applying a fed-batch strategy, the final production yield and conversion rate of α-arbutin reached 60.9 g/L and 95.5%, respectively, which is the highest reported yield by engineered strains. Compared to the highest reported value (<1.4 g/L/h), our productivity (7.6 g/L/h) was improved more than five-fold. This work represents an efficient and rapid method for α-arbutin production with potential industrial applications.


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