169,889 research outputs found
Comments on the 'China model'
This paper reviews the articles by Pan and by Zhu on the China Model. The review of Pan is critical, that of Zhu sympathetic. Pan is criticised for taking an unquestioning attitude towards state supporting ideologies and failing to adequately account for the effects of changes in family structure and class structure in China over the past 50 years. The reviewer broadly agrees with Zhu's comments about a future steady state economy. The article provides statistical data from the recent economic and demographic histories of China and Japan to back up the general conclusions drawn by Zhu
Measurement of the c+ decay-asymmetry parameter
complete author list: Avery P.; Besson D.; Garren L.; Yelton J.; Kinoshita K.; Pipkin F.; Procario M.; Wilson R.; Wolinski J.; Xiao D.; Zhu Y.; Ammar R.; Baringer P.; Coppage D.; Davis R.; Haas P.; Kelly M.; Kwak N.; Lam H.; Ro S.; Kubota Y.; Nelson J.; Perticone D.; Poling R.; Fulton R.; Jensen T.; Johnson D.; Kagan H.; Kass R.; Morrow F.; Whitmore J.; Wilson P.; Bortoletto D.; Chen W.; Dominick J.; McIlwain R.; Miller D.; Ng C.; Schaffner S.; Shibata E.; Shipsey I.; Yao W.; Battle M.; Sparks K.; Thorndike E.; Wang C.; Alam M.; Kim I.; Li W.; Romero V.; Sun C.; Wang P.; Zoeller M.; Goldberg M.; Haupt T.; Horwitz N.; Jain V.; Mestayer M.; Moneti G.; Rozen Y.; Rubin P.; Sharma V.; Skwarnicki T.; Thulasidas M.; Zhu G.; Barnes A.; Csorna S.; Letson T.; Alexander J.; Artuso M.; Bebek C.; Berkelman K.; Browder T.; Cassel D.; Cheu E.; Coffman D.; Crawford G.; Dewire J.; Drell P.; Ehrlich R.; Galik R.; Garcia-Sciveres M.; Geiser B.; Gittelman B.; Gray S.; Halling A.; Hartill D.; Heltsley B.; Honscheid K.; Kandaswamy J.; Katayama N.; Kreinick D.; Lewis J.; Ludwig G.; Masui J.; Mevissen J.; Mistry N.; Nandi S.; Nordberg E.; Ogrady C.; Peterson D.; Pisharody M.; Riley D.; Sapper M.; Selen M.; Silverman A.; Stone S.; Worden H.; Worris M.; Sadoff A.; Avery P.; Sadoff A.; Worris M.; Worden H.; Stone S.; Silverman A.; Avery P.</p
KnowVolution: Redesigning enzymes for innovations
Directed evolution has matured in academia and industry to a routinely applied algorithm to tailor enzyme properties1 to match especially demands in synthesis and material science. In order to free directed enzyme evolution from methodological restraints and to efficiently explore its potential, one has to balance time requirements for a directed evolution campaign, the number of generated enzyme variants, and limitations in state of the art screening technologies. For instance, saturation mutagenesis of six amino acid positions in an enzyme, which usually consists of \u3e50 amino acids, yields 64 million (206) different enzyme variants. The latter represents the upper throughput for activity-based screening systems2.
In essence, protein engineers have to accept that they will not be able to sample through the theoretical obtainable sequence space of enzyme variants and smarter strategies are required for efficient directed enzyme evolution. The KnowVolution (Knowledge gaining direct evolution)3 approach represents such a directed evolution 2.0 strategy, which identifies in four phase with limited screening efforts, significantly improved enzymes variants and ensures a molecular understanding of improved enzyme properties. Three out of six in a review reported KnowVolution campaigns3 were commercialized by industrial partners; thereby limiting the number of substitutions turned out to be a key prerequisite for maintaining thermal resistance, process stability and selectivity.
In addition, directed enzyme evolution by random mutagenesis will be compared to improvements that are obtainable with a variant library that contains all natural possible diversity with ONE amino acid exchange (SSM library)4. The comparison of 3000 mutations from random mutagenesis libraries with the SSM library taught us how many of the natural occurring beneficial positions are obtainable or unobtainable by state of art methodologies in directed evolution and provided first insights on general design principles to improve enzymatic resistance in organic cosolvents4 and ionic liquids4.
References:
(1) a.Shivange, A. V., Marienhagen, J., Mundhada, H., Schenk, A., Schwaneberg, U. (2009). Curr. Opin. Chem. Biol. 13, 19. b.Ruff, A. J., Dennig, A., Schwaneberg, U. (2013). FEBS J. 280, 2961.
(2) a.Körfer, G., Pitzler, C., Vojcic, L., Martinez, R., Schwaneberg, U. (2016). Scientific Reports, 6, 1-12. b.LĂŒlsdorf, N., Pitzler, C., Biggel, M., Martinez, R., Vojcic, L., Schwaneberg, U. (2015). Chem. Commun. 51, 8679. c.Ruff, A. J., Dennig, A., Wirtz, G., Blanusa, M., Schwaneberg, U. (2012). ACS Catalysis 2, 2724.
(3) Cheng, F., Zhu, L., Schwaneberg, U. (2015). Chem. Commun. 51, 9760.
a.Zhao, J., Frauenkron-Machedjou, V. J., Kardashliev, T., Ruff, A. J., Zhu, L., Bocola, M., Schwaneberg, U. (2017). Appl. Microbiol. Biotechnol., 2017, DOI: 10.1007/s00253-016-8035-1. b.Frauenkron-Machedjou, V. J., Fulton, A., Zhu, L., Bocola, M., Zhu, L., Jaeger, K.-E., Schwaneberg, U. (2015). ChemBioChem, 16, 937-945. c.Zhao, J., Kardashliev, T., Ruff, A. J., Bocola, M., Schwaneberg, U. (2014). Biotechnol. Bioeng. 111, 2380
Retracted: Inhibition of Corneal Neovascularization by Hydrazinocurcumin
This article previously published in Volume 15 Issue 2 of this journal in February 2016 has been retracted in line with the guidelines from the Committee on Publication Ethics (COPE, http://publicationethics.org/resources/guidelines)Retracted: Zhan W, Zhu J, Zhang Y. Inhibition of corneal neovascularization by hydrazinecurcumin. Trop J Pharm Res 2016; 15(2):349-354 doi: http://dx.doi.org/10.4314/tjpr.v15i2.18
In vivo assessment of the mechanical properties of the child cortical bone using quantitative computed tomography
The mechanical properties of the rib cortical bone are extremely rare on children due to difficulties to obtain specimens to perform conventional tests. Some recent studies used cadaveric bones or bone tissues collected during surgery but are limited by the number of samples that could be collected. A non-invasive technique could be extremely valuable to overcome this limitation. It has been shown that a relationship exists between the mechanical properties (apparent Youngâs modulus and ultimate strength) and the bone mineral density (assessed using Quantitative Computed Tomography, QCT), for the femur and recently by our group for the adult ribs ex vivo. Thus the aim of this study was to assess the mechanical properties of the child rib cortical bone using both QCT images in vivo and the previous relationship between bone mineral density and mechanical properties of the rib cortical bone. Twenty-eight children were included in this study. Seven age-groups have been considered (1, 1.5, 3, 6, 10, 15, 18 years old). The QCT images were prescribed for various thoracic pathologies at the pediatric hospital in Lyon. A calibration phantom was added to the clinical protocol without any modifications for the patient. The protocol was approved by the ethical committee. A 3D reconstruction of each thorax was performed using the QCT images. A custom software was then used to obtain cross-sections to the rib midline. The mean bone mineral density was then computed by averaging the Hounsfield Units in a specific cross-section and by converting the mean value (Hounsfield Units) in bone mineral density using the calibration phantom. This bone mineral density was assessed for the 6th rib of each subject. Our relationship between the bone mineral density and the mechanical properties of the rib cortical bone was used to derive the mechanical properties of the child ribs in vivo. The results give values for the apparent Youngâs modulus and the ultimate strength. The mechanical properties increase along growth. As an example the apparent Youngâs modulus in the lateral region ranges from 7 GPa +/-3 at 1 year old up to 13 GPa +/- 2 at 18 years old. These data are in agreement with the few previous values obtained from child tissues. This methodology opens the way to in vivo measurement of the mechanical properties of the child cortical bone based on calibrated QCT images
Retracted: MiR-10b alleviates high glucose-induced human retinal endothelial cell injury by regulating TIAM1 signaling
This article previously published in Volume 19 Issue 8 of this journal in August 2020 has been retracted in line with the guidelines from the Committee on Publication Ethics (COPE, http://publication ethics.org/resources/guidelines).Retraction: Chen Y, Zhu Y, Zhao S. MiR-10b alleviates high glucose-induced human retinal endothelial cell injury by regulating TIAM1 signaling. Trop J Pharm Res, 2020, 19(8): 1577-1583.To the editor:I am retracting this article because some of the results we presented are irreproducible.Signed: Sheng Zha
Recommended from our members
Identifying patterns of weight-related health behaviors among US adolescents, and associated risk of obesity
Little is known about the current complex pattern of weight-related health behaviors among adolescents in the US. The goal of this report was to develop and examine a comprehensive latent class analysis (LCA) model examining the prevalence of combined associations of physical activities sedentary behaviors, and eating behaviors with obesity among female and male US adolescents (n= 12,031). Four classes and five classes were identified for female and male adolescents, respectively. Among which, three were similar and were characterized as âInactive/ Low screen time/ Poor eating habitâ, âInactive/ Moderately high screen time/ Poor eating habitâ, and âActive/ Low screen time/ Poor eating habit'. Additionally, âInactive/ Low screen time/Good eating habitâ was unique to female adolescents, while âModerately active/ High screen time/ Good eating habit' and âModerately active/ Low screen time/ Good eating habit' were unique to males. Furthermore, the proportion of normal weight, overweight, and obese in each class was examined across females and males. The results showed that male adolescents had a higher proportion of people being obese than female adolescents in each class. The findings from this report provided insights on the current health needs of US adolescents and implied that gender-specific intervention strategies were required to reduce the risk of obesity among adolescents.Statistic
Calculation of core losses under DC bias and harmonics based on Jiles-Atherton dynamic hysteresis model combined with finite element analysis
© 2017 IEEE. This paper presents a method to calculate the core losses in SiFe laminations under magnetizations with DC bias and harmonics. DC bias is usually generated by the ground return current of high voltage direct current (HVDC) system intrude into the windings of neutral-grounded transformers, which leads to increase of harmonics and core loss. For accurate calculation of core losses under DC bias, the Jiles-Atherton (J-A) dynamic hysteresis model is incorporated into the finite element method. The J-A dynamic hysteresis model is constructed by combining the traditional J-A hysteresis model with the models of instantaneous eddy current and excess losses. To account for the DC bias, the J-A dynamic model was modified by adjusting the parameters of instantaneous excess loss model. The theoretical results are verified by the measured results by a Single-Sheet Tester (SST 500)
- âŠ