Bromo-oxidation reaction in enzyme-entrapped alginate hollow microfibers

In this article, the authors present the fabrication of an enzyme-entrapped alginate hollow fiber using a microfluidic device. Further use of enzyme-entrapped alginate hollow fibers as a biocatalytic microchemical reactor for chemical synthesis is also deliberated in this article. To ensure that there is no enzyme leaching from the fiber, fiber surfaces were coated with chitosan. To confine the mobility of reactants and products within the porous hollow fibers the entire fibers were embedded into a transparent polydimethylsiloxane (PDMS) matrix which also works as a support matrix. A vanadium-containing bromoperoxidase enzyme isolated from Corallina confusa was used as a model enzyme to demonstrate the use of these alginate hollow-fiber reactors in bromo-oxidation of phenol red to bromophenol blue at different dye flow rates. Stability of the entrapped enzyme at different temperatures and the effect of the chitosan coating on the reaction conversion were also studied. It was observed that molecules as big as 27 kDa can be retained in the matrix after coating with chitosan while molecules with molecular-weight of around 378 Da can still diffuse in and out of the matrix. The kinetic conversion rate in this microfluidic bioreactor was more than 41-fold faster when compared with the standard test-tube procedure.     

Countermovement jump performance assessment using a wearable 3D inertial measurement unit

The aim of this study was to validate a wearable inertial measurement unit (IMU), containing a 3D accelerometer and gyroscope, for the estimation of countermovement jump height. The absolute vertical acceleration of the IMU positioned on the back of the participant at L5 level, compensated for trunk rotations, was used to obtain jump height by applying the equation of free-fall to the motion of the IMU. The methodology was tested on 28 participants performing five countermovement jumps each. A reference value for this quantity was obtained using stereophotogrammetry (35.4 cm, s = 4.9). Jump height scores obtained using the proposed methodology (35.9 cm, s = 5.5) presented no significant difference with respect to stereophotogrammetry (P = 0.61). A low bias of 0.6 cm confirmed the accuracy of the estimate, which also showed a high (r = 0.87) and significant (P < 0.0001) correlation with reference values. Furthermore, without compensating accelerations for trunk rotation, jump height was largely underestimated (P < 0.0001) (bias: -12.7 cm) and poorly associated (r = 0.31) with stereophotogrammetry. The results of this study show that the estimation of jump height using inertial sensors leads to accurate results when the measured accelerations are corrected for trunk rotations.     

Movement patterns and physical strain during a novel, simulated cricket batting innings (BATEX)

A simulated cricket batting innings was developed to replicate the physical demands of scoring a century during One-Day International cricket. The simulated innings requires running-between-the-wickets across six 5-over stages, each of 21 min duration. To validate whether the simulated batting innings is reflective of One-Day International batting, movement patterns were collected using a global positioning system (GPS) and compared with previous research. In addition, indicators of physical strain were recorded (heart rate, jump heights, sweat loss, tympanic temperature). Nine club cricketers (mean ± s: age 20 ± 3 years; body mass 79.5 ± 7.9 kg) performed the simulated innings outdoors. There was a moderate trend for distance covered in the simulated innings to be less than that during One-Day batting (2171 ± 157 vs. 2476 ± 631 m · h?1; effect size = 0.78). This difference was largely explained by a strong trend for less distance covered walking in the simulated innings than in One-Day batting (1359 ± 157 vs. 1604 ± 438 m · h?1; effect size = 1.61). However, there was a marked trend for distance covered both striding and sprinting to be greater in the simulated innings than in One-Day batting (effect size > 1.2). Practically, the simulated batting innings may be used for match-realistic physical training and as a research protocol to assess the demands of prolonged, high-intensity cricket batting.     

The role of athlete narcissism in moderating the relationship between coaches' transformational leader behaviors and athlete motivation

Leadership research that examines follower characteristics as a potential moderator of leadership effectiveness is lacking. Within Bass's (1985) transformational leadership framework, we examined follower narcissism as a moderator of the coach behavior-coach effectiveness relationship. Youth athletes (male = 103, female = 106) from the Singapore Sports Academy (mean age = 14.28, SD = 1.40 years) completed the Differentiated Transformational Leadership Inventory (Callow, Smith, Hardy, Arthur, & Hardy, 2009), the Narcissistic Personality Inventory (Raskin & Terry, 1988), and indices of follower effort. Multilevel analyses revealed that athlete narcissism moderated the relationship between fostering acceptance of group goals and athlete effort and between high performance expectations and athlete effort. All the other transformational leader behaviors demonstrated main effects on follower effort, except for inspirational motivation.     

全球公共物品

面对新冠疫情的爆发,中国没有太多考虑经济问题,选择采取严格防控措施.这与西方世界流行的做法形成鲜明对比,即我们都接受某种程度的"灵活"封闭,主要目的是挽救老年人的生命.然而中国人却在创纪录的短时间内扩大了医院的容量,并带回了居住在国外的中国公民,这几乎都不在大多数西方国家的考虑之列.     

美国非本土博士与本土博士的工作角色与薪酬比较———对美国1999—2008年博士学位获得者的调查

对那些参与了美国国家科学基金会博士学位获得者调查（SDR）的非美国本土的博士学位获得者完成学业后的工资、工资增长和就业单位等方面进行了调查,调查结果显示,非美国本土的劳动者在1999年的平均年薪比美国本土的同行低,但是10年后的2008年,非美国本土的劳动者的工资超过了那些美国本土的同行.分析还发现,非美国本土与美国本土的博士10年间工资增长存在差异.差异可能是由于学科专业和市场需求等因素导致的.     

高校图书馆读者服务工作的创新

文章分析了高校图书馆读者服务过程中存在的问题及面临的挑战,提出加强对读者导读工作,提高读者工作的服务水平,开展网络信息服务与咨询服务,各高校图书馆之间实现资源共享等一系列创新图书馆读者服务工作的举措。     

贝多芬的吻

我16岁时,由于与音乐教师发生分歧,处于某种危机之中。后来,一个著名的钢琴家艾米尔·冯·萨尔——李斯特最后一个活着的弟子,来到布达佩斯,要求我为他弹奏。他专心地听我弹了巴赫的C大调《Toccata》,并要求听更多的曲子。我全身心投入弹奏贝多芬的《Pathetique》奏鸣曲和舒曼的作品《Papillons》之中。最后,艾米尔·冯·萨尔起身,在我的前额上吻了一下。＂我的孩子,＂他说,＂在像你这么大时,我成了李斯特的学生。     

给伊丽莎白一支红玫瑰

伊丽莎白捧着一束雏菊走到院子里。 “美丽的鲜花献给……给……噢,我看我永远都说不好了!”她叫着,把雏菊扔到地上。     

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