Novel additive for sperm cryopreservation media: Holotheria parva coelomic cavity extract protects human spermatozoa against oxidative stress—A pilot study

Cryopreservation is the most effective method for preserving semen for a long period of time. However, during the freeze–thaw process, production of reactive oxygen species (ROS) leads to a steep reduction in sperm fertility indices. In this study, we tested the effects of the extract of the coelomic cavity of five Holotheria parva, a marine organism rich in antioxidants, for its ROS-scavenging activity and cryoprotective effects on oxidative stress. Using a total of 50 semen samples, our results demonstrated that doses of 250 and 500 µg/ml of H. parva coelomic cavity extract significantly increased sperm vitality as compared to the control (p <.05). The addition of 250 µg/ml of the extract exerted a significant positive effect on sperm motility. Moreover, sperm DNA damage and ROS production were significantly reduced at extract concentrations of 250 and 500 µg/ml (p <.05). To the best of our knowledge, the results of this study represent the first demonstration of the possibility of improving sperm parameters and reducing ROS production and DNA damage by supplementing sperm freezing media with H. parva coelomic extract. Our results suggested that H. parva coelomic extract could be useful for improving the fertilising ability of frozen-thawed human semen

Turn-turn short circuit fault management in permanent magnet machines

This paper presents a systematic study on turn-turn short circuit fault and ways to manage them to provide a basis for comparison of the various options available. The possible methods to reduce the likelihood of the winding SC fault and the fault mitigation techniques related to such faults are discussed. A Finite Element (FE) analysis of a surface-mount Permanent Magnet (PM) machine under application of different mitigation techniques during a turn-turn fault is presented. Both machine and drive structural adaptations for different fault mitigation techniques are addressed. Amongst the investigated fault mitigation techniques, the most promising solution is identified and validated experimentally. It is shown that the shorting terminal method adopting vertical winding arrangement is an effective method in terms of the implementation, reliability and weight

Path analysis of the relationship between optimism, humor, affectivity, and marital satisfaction among infertile couples

Marital satisfaction is an important factor for establishing a family relationship, feeling satisfied, and living happily together. The aim of the present study was to investigate the relationship between optimism, humor, positive and negative affect, and marital satisfaction among infertile couples. The sample comprised 80 infertile Iranian couples (n = 160) who visited infertility clinics. Participants completed a series of Persian versions of psychometric scales related to optimism (Attributional Style Questionnaire), humor (Humor Styles Questionnaire), marital satisfaction (Enrich Marital Satisfaction Questionnaire), positive affect (PA) and negative affect (NA) (Positive and Negative Affect Schedule). The obtained result of Smart PLS statistical analysis confirmed the significant positive correlation between optimism and humor with marital satisfaction and high PA and low NA. Moreover, the findings also provided an adequate fit of the model. The findings demonstrated that infertile couples high in optimism and humor have higher levels of marital satisfaction and high PA and low PA. Based on the study’s findings, interventions for facilitating optimism and humor among infertile couples are discussed

Purification and immobilization of engineered glucose dehydrogenase: A new approach to producing gluconic acid from breadwaste

Background Platform chemicals are essential to industrial processes. Used as starting materials for the manufacture of diverse products, their cheap availability and efficient sourcing are an industrial requirement. Increasing concerns about the depletion of natural resources and growing environmental consciousness have led to a focus on the economics and ecological viability of bio-based platform chemical production. Contemporary approaches include the use of immobilized enzymes that can be harnessed to produce high-value chemicals from waste. Results In this study, an engineered glucose dehydrogenase (GDH) was optimized for gluconic acid (GA) production. Sulfolobus solfataricus GDH was expressed in Escherichia coli. The Km and Vmax values for recombinant GDH were calculated as 0.87 mM and 5.91 U/mg, respectively. Recombinant GDH was immobilized on a hierarchically porous silica support (MM-SBA-15) and its activity was compared with GDH immobilized on three commercially available supports. MM-SBA-15 showed significantly higher immobilization efficiency (> 98%) than the commercial supports. After 5 cycles, GDH activity was at least 14% greater than the remaining activity on commercial supports. Glucose in bread waste hydrolysate was converted to GA by free-state and immobilized GDH. After the 10th reuse cycle on MM-SBA-15, a 22% conversion yield was observed, generating 25 gGA/gGDH. The highest GA production efficiency was 47 gGA/gGDH using free-state GDH. Conclusions This study demonstrates the feasibility of enzymatically converting BWH to GA: immobilizing GDH on MM-SBA-15 renders the enzyme more stable and permits its multiple reuse

Enzyme immobilization: an update

Compared to free enzymes in solution, immobilized enzymes are more robust and more resistant to environmental changes. More importantly, the heterogeneity of the immo-bilized enzyme systems allows an easy recovery of both enzymes and products, multiple re-use of enzymes, continuous operation of enzymatic processes, rapid termination of reactions, and greater variety of bioreactor designs. This paper is a review of the recent literatures on enzyme immobilization by various techniques, the need for immobilization and different applications in industry, covering the last two decades. The most recent papers, patents, and reviews on immobilization strategies and application are reviewed

Children's active school travel : the effect of a school-based intervention and an investigation of psychological predictors

Background: Studies are needed that rigorously evaluate active travel interventions using objective physical activity outcome measures. Additionally, little is known about the psychological predictors of children's school travel behaviour. Increased understanding in these two areas will aid in the promotion of active school travel. Purpose: This thesis reports the rationale, methods, and results for an evaluation of the Travelling Green intervention and identifies important psychological predictors of children's school travel behaviour. Method: Participants were 166 children (age 8-9 years, 60% male) from five Scottish primary schools and 143 parents (mean age 40, 13% male). Children's school travel behaviour was measured across 5 days pre- and post-intervention using accelerometers. Children and parents completed a travel questionnaire that gathered data on various aspects of and attitudes towards walking to school. The questionnaire also generated data on psychological factors (self-efficacy and outcome expectations) related to school travel. A quasi-experimental design with an intervention (n = 79) and comparison (n= 87) group was used to investigate the effects of Travelling Green on commuting behaviour. Baseline cross-sectional data were used to identify the psychological predictors of walking to school. Results: Commuting-related physical activity decreased from pre- to post-intervention in the intervention and comparison groups. Daily physical activity decreased less in the intervention group compared to the comparison group. Parental self-efficacy for their child's ability to carry out commuting-related tasks was the only psychological predictor of commuting behaviour. Parents were the primary decision makers regarding their child's travel mode. Conclusion: Travelling Green does not resuti in an increase in school travel-related physical activity, but may attenuate a seasonally related decrease in daily physical activity levels in 8-9 year old children. School travel interventions should be focused on parents of younger children as they are the gatekeepers of their child's behaviour at this age. Alternatively,interventions should be developed for older children who have the autonomy to change their travel behaviours.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

An Enhanced Distributed Congestion Control Method for Classical 6LowPAN Protocols Using Fuzzy Decision System

The classical Internet of things routing and wireless sensor networks can provide more precise monitoring of the covered area due to the higher number of utilized nodes. Because of the limitations in shared transfer media, many nodes in the network are prone to the collision in simultaneous transmissions. Medium access control protocols are usually more practical in networks with low traffic, which are not subjected to external noise from adjacent frequencies. There are preventive, detection and control solutions to congestion management in the network which are all the focus of this study. In the congestion prevention phase, the proposed method chooses the next step of the path using the Fuzzy decision-making system to distribute network traffic via optimal paths. In the congestion detection phase, a dynamic approach to queue management was designed to detect congestion in the least amount of time and prevent the collision. In the congestion control phase, the back-pressure method was used based on the quality of the queue to decrease the probability of linking in the pathway from the pre-congested node. The main goals of this study are to balance energy consumption in network nodes, reducing the rate of lost packets and increasing quality of service in routing. Simulation results proved the proposed Congestion Control Fuzzy Decision Making (CCFDM) method was more capable in improving routing parameters as compared to recent algorithms