Proton transport in crystalline, porous covalent organic frameworks: a NMR study

Proton transport in crystalline, porous covalent organic frameworks: a NMR stud

Greenlip abalone (Haliotis laevigata Donovan, 1808) sperm cryopreservation using a programmable freezing technique and testing the addition of amino acid and vitamin

This study investigated factors key to the development of sperm cryopreservation in the greenlip abalone Haliotis laevigata using a programmable freezing technique, including (1) permeable cryoprotectant agent (CPA) selection; (2) cooling rate; (3) endpoint temperature; (4) thawing temperature; (5) sperm to egg ratio and (6) sugar, vitamin and amino acid supplementation, using sperm motility, fertilization rate, plasma membrane integrity, mitochondrial membrane potential or acrosome integrity as quality assessment indicators. Results showed that among the permeable CPAs evaluated, 10% dimethyl sulfoxide was the most suitable for greenlip abalone sperm cryopreservation. The highest post-thaw sperm motility was achieved with the sperm being frozen at a cooling rate of -5°C min-1 to -30°C from 0°C and thawed and recovered in 40°C and 18°C seawater baths respectively. The addition of sugars in 10% dimethyl sulfoxide did not significantly improve the post-thaw sperm motility and fertilization rate. The addition of 0.6% glycine, 0.2% taurine or 0.02% L-ascorbic acid, on the other hand, significantly improved the post-thaw sperm motility. However, only the addition of 0.6% glycine improved the post-thaw sperm fertilization rate, which was further confirmed by the improvement of the post-thaw sperm mitochondrial membrane potential and acrosome integrity through flow cytometry analysis

Cryopreservation of sperm in farmed Australian greenlip abalone Haliotis laevigata

This study investigated factors important to the development of the liquid nitrogen (LN) vapor sperm cryopreservation technique in farmed greenlip abalone Haliotis laevigata, including (1) cryoprotectant agent (CPA) toxicity; (2) cooling temperature (height above LN surface); (3) thawing temperature; (4) sperm to egg ratio; and (5) sugar supplementation, using sperm motility, fertilization rate or integrity/potential of sperm components and organelles as quality assessment indicators. Results suggested that among the single CPAs evaluated 6% dimethyl sulfoxide (Me2SO) would be the most suitable for sperm cryopreservation in this species. The highest post-thaw sperm motility was achieved with the sperm that had been exposed to LN vapor for 10. min at 5.2. cm above the LN surface, thawed and recovered in 60 and 18. °C seawater bathes, respectively after at least 2. h storage in LN. The highest fertilization rates were achieved at a sperm to egg ratio of 10,000:1 or 15,000:1. Addition of 1% glucose or 2% sucrose produced significantly higher post-thaw sperm motility than 6% Me2SO alone. Among the three cryoprotectant solutions further trialled, 6% Me2SO. +. 1% glucose produced the highest fertilization rate of 83.6. ±. 3.7%. Evaluation of sperm has shown that the addition of glucose could significantly improve the sperm plasma membrane integrity and mitochondrial membrane potential. These results demonstrated a positive role of glucose in the improvement of sperm cryopreservation in farmed greenlip abalone. © 2014 Elsevier Inc

Cryopreservation of sperm in farmed blacklip abalone (Haliotis rubra Leach, 1814)

This study developed a technique of sperm cryopreservation using liquid nitrogen (LN) vapour in farmed blacklip abalone Haliotis rubra through evaluating the following five key factors: (1) cryoprotectant agent (CPA) toxicity; (2) cooling temperature; (3) thawing temperature; (4) sperm to egg ratio and (5) sugar addition, using sperm motility or fertilization rate as quality assessment indicators. The results demonstrated that 6% dimethyl sulfoxide (DMSO) was the best single CPA for sperm cryopreservation in this species. The highest post-thaw sperm motility was achieved when sperm were exposed to LN vapour for 10min at 5.2cm above the LN surface and thawed at 60°C and recovered at 16°C in seawater baths. Post-thaw sperm motility was found to be significantly higher when 6% DMSO was used in combination with 1% or 2% glucose than 6% DMSO alone. Further evaluation of fertilization rate between these CPAs showed that 6% DMSO+2% glucose achieved the highest fertilization rate of 70% at a sperm to egg ratio of 10000:1

Effects of Broodstock Age and Sperm Collection Time over a Natural Spawning Period on Sperm Cryopreservation in Farmed Greenlip Abalone, Haliotis laevigata

ABSTRACTThis study investigated the effects of broodstock age (2‐ and 3‐yr‐old), and sperm collection time at the beginning, middle, and end of a natural spawning period, on the ability of sperm to tolerate cryopreservation in farmed greenlip abalone, Haliotis laevigata. The quality of sperm was assessed by motility, fertilization rate, plasma membrane integrity, mitochondrial membrane potential (MMP), and acrosome integrity (AI). The sperm collected at the middle of a natural spawning period had significantly higher quality than those collected at the beginning and the end of the spawning period in terms of plasma membrane integrity, MMP, and AI of fresh and post‐thaw sperm, post‐thaw sperm motility, and fertilization rate. No significant difference was found between 2‐ and 3‐yr‐old animals in most quality parameters evaluated. The results suggested that sperm collected during the middle of the spawning season should be used for cryopreservation. The efficiency of genetic improvement programs can be further enhanced by using sperm collected from 2‐yr‐old abalone which has a similar ability to tolerate cryopreservation as 3‐yr‐old counterparts

Improvement in non-programmable sperm cryopreservation technique in farmed greenlip abalone Haliotis laevigata

This study assessed the effects of the addition of vitamins (. l-ascorbic acid), amino acids (glycine and taurine), and monosaccharides (glucose, fructose and galactose) on sperm cryopreservation using a non-programmable freezing technique in farmed greenlip abalone. The results showed that the addition of taurine, glycine or l-ascorbic acid significantly improved the post-thaw sperm motility, whereas the post-thaw sperm fertilization rates were improved by the addition of glycine or l-ascorbic acid. Flow cytometry analysis demonstrated that the addition of glycine significantly enhanced the post-thaw sperm plasma membrane integrity and acrosome integrity. Results from the investigation on monosaccharides demonstrated that glucose, fructose and galactose had a similar cryoprotective effect, resulting in a similar level of the post-thaw sperm fertilization rate, plasma membrane integrity, mitochondrial membrane potential and acrosome integrity. In this study, the highest post-thaw fertilization rate of 96% was achieved by using the cryoprotective mediums containing 6% DMSO, 1% glucose and 0.6% glycine

Chinese perspectives on aquaculture careers: Insights from post-graduate students and early career researchers

Chinese perspectives on aquaculture careers: Insights from post-graduate students and early career researcher

Trends in percentages of gestational diabetes mellitus attributable to overweight, obesity, and morbid obesity in regional Victoria: an eight-year population-based panel study

Background: Gestational diabetes mellitus (GDM) is the fastest growing type of diabetes in Australia with rates trebling over the past decades partially explained by rising obesity rates and maternal age among childbearing women. Percentage of GDM attributable to obesity has been documented, mostly focusing on metropolitan populations. In parts of regional (areas outside capital cities) and rural Australia where overweight, obesity and morbid obesity are more prevalent, intertwined with socioeconomic disadvantage and higher migrant communities, trends over time in adjusted percentages of GDM attributed to obesity are unknown. Methods: In this population-based retrospective panel study, women, without pre-existing diabetes, delivering singletons between 2010 and 2017 in a tertiary regional hospital that serves 26% of Victoria’s 6.5 million Australian population were eligible for inclusion. Secular trends in GDM by body mass index (BMI) and age were evaluated. The percentage of GDM that would have been prevented each year with the elimination of overweight or obesity was estimated using risk-adjusted regression-based population attributable fractions (AFp). Trends in the AFp over time were tested using the augmented Dickey-Fuller test. Results: Overall 7348 women, contributing to 10,028 births were included. The age of expecting mothers, their BMI, proportion of women born overseas, and GDM incidence significantly rose over time with GDM rising from 3.5% in 2010 to 13.7% in 2017, p < 0.001, increasing in all BMI categories. The incidence was consistently highest among women with obesity (13.8%) and morbid obesity (21.6%). However, the highest relative increase was among women with BMI < 25 kg/m2, rising from 1.4% in 2010 to 7.0% in 2017. Adjusting for age, country of birth, socioeconomic status, comorbidities, antenatal and intrapartum factors, an estimated 8.6% (confidence interval (CI) 6.1–11.0%), 15.6% (95% CI 12.2–19.0%), and 19.5% (95% CI 15.3–23.6%) of GDM would have been prevented by eliminating maternal overweight, obesity, and morbid obesity, respectively. However, despite the rise in obesity over time, percentages of GDM attributable to overweight, obesity, and morbid obesity significantly dropped over time. Scenario analyses supported these findings. Conclusions: Besides increasing prevalence of obesity over time, this study suggests that GDM risk factors, other than obesity, are also increasing over time

Proteome profiling of exosomes derived from human primary and metastatic colorectal cancer cells reveal differential expression of key metastatic factors and signal transduction components

Exosomes are small extracellular 40-100 nm diameter membrane vesicles of late endosomal origin that can mediate intercellular transfer of RNAs and proteins to assist premetastatic niche formation. Using primary (SW480) and metastatic (SW620) human isogenic colorectal cancer cell lines we compared exosome protein profiles to yield valuable insights into metastatic factors and signaling molecules fundamental to tumor progression. Exosomes purified using OptiPrep™ density gradient fractionation were 40-100 nm in diameter, were of a buoyant density ∼1.09 g/mL, and displayed stereotypic exosomal markers TSG101, Alix, and CD63. A major finding was the selective enrichment of metastatic factors (MET, S100A8, S100A9, TNC), signal transduction molecules (EFNB2, JAG1, SRC, TNIK), and lipid raft and lipid raft-associated components (CAV1, FLOT1, FLOT2, PROM1) in exosomes derived from metastatic SW620 cells. Additionally, using cryo-electron microscopy, ultrastructural components in exosomes were identified. A key finding of this study was the detection and colocalization of protein complexes EPCAM-CLDN7 and TNIK-RAP2A in colorectal cancer cell exosomes. The selective enrichment of metastatic factors and signaling pathway components in metastatic colon cancer cell-derived exosomes contributes to our understanding of the cross-talk between tumor and stromal cells in the tumor microenvironment. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.</p

Nanoscale niobium oxides anode for electrochemical lithium and sodium storage: a review of recent improvements

Abstract: In recent years, Nb-based oxides, especially Nb2O5, due to their unique structural advantages, have stimulated scholars’ extensive research enthusiasm in the field of energy storage systems including lithium ion batteries (LIBs) and sodium ion batteries (SIBs), excellent chemical stability and outstanding rate capability dominated by pseudocapacitive nature. In addition, Nb-based oxides usually have a higher operating voltage (> 1.0 V vs Li+/Li), which can effectively prevent the decomposition of organic electrolytes and the formation of solid electrolyte interface films in batteries. This review systematically summarizes the different crystal structures of Nb2O5 and the lithium storage mechanism based on theoretical calculations, as well as the comparison of various synthesis strategies. In addition, the advanced research progress of niobium-based oxides as anode materials in LIBs and SIBs is summarized from the perspective of nanostructure control engineering that affects electrochemical performance. It also puts forward reasonable cognition and challenges for future research, which is conducive to the design of energy storage equipment that meets the needs of sustainable development. Graphic abstract: The design and optimization of various synthesis methods facilitate the formation of a variety of heterogeneous nanostructures, leading to reversible storage of Li and Na ions. [Figure not available: see fulltext.