139 research outputs found
"Keeping a Safe Confession Distance between Strangers": The Spatial Structure of Social Accessibility in Networked Communities and Risk Avoidance of Stranger Confessions
This study focuses on the spatial structure of stranger social accessibility in networked communities and risk avoidance when socializing with strangers. Using Confession WallΒ as an example, this study contends that community social media fosters new connections by compensating for accessibility issues between strangers in local communities through flexible mediation of online and offline social interactions. This connectivity minimizes the costs and risks of emotional interactions between strangers in semi-acquaintance communities. This compensation for social accessibility highlights the value of digital media, especially community social media as a geomedia, in energizing communities and facilitating interactions between strangers. This is crucial in understanding the emotional interactions between strangers and how they are mediated by community social media in settings where acquaintances and complete strangers intermingle
Ion Exchange Membranes for Electrodialysis: A Comprehensive Review of Recent Advances
Electrodialysis related processes are effectively applied in desalination of sea and brackish water, waste water treatment, chemical process industry, and food and pharmaceutical industry. In this process, fundamental component is the ion exchange membrane (IEM), which allows the selective transport of ions. The evolvement of an IEM not only makes the process cleaner and energy-efficient but also recovers useful effluents that are now going to wastes. However ion-exchange membranes with better selectivity, less electrical resistance, good chemical, mechanical and thermal stability are appropriate for these processes. For the development of new IEMs, a lot of tactics have been applied in the last two decades. The intention of this paper is to briefly review synthetic aspects in the development of new ion-exchange membranes and their applications for electrodialysis related processes
Sulfonated microporous polymer membranes with fast and selective ion transport for electrochemical energy conversion and storage
Membranes with fast and selective transport of protons and cations are required for a wide range of electrochemical energy conversion and storage devices, such as proton-exchange membrane (PEM) fuel cells and redox flow batteries. Here we report a new approach to designing solution-processable ion-selective polymer membranes with both intrinsic microporosity and ion-conductive functionality. This was achieved by synthesizing polymers with rigid and contorted backbones, which incorporate hydrophobic fluorinated and hydrophilic sulfonic acid functional groups, to produce membranes with negatively-charged subnanometer-sized confined ionic channels. The facilitated transport of protons and cations through these membranes, as well as high selectivity towards nanometer-sized redox-active molecules, enable efficient and stable operation of an aqueous alkaline quinone redox flow battery and a hydrogen PEM fuel cell. This membrane design strategy paves the way for producing a new-generation of ion-exchange membranes for electrochemical energy conversion and storage applications
Evaluation of polymyxin B AUC/MIC ratio for dose optimization in patients with carbapenem-resistant Klebsiella pneumoniae infection
Polymyxin B has been used as a last-line therapy for the treatment of carbapenem-resistant gram-negative bacterial infection. The pharmacokinetic/pharmacodynamic index (AUC/MIC) of polymyxin B has not been clinically evaluated, given that the broth microdilution method for polymyxin susceptibility testing is rarely used in hospitals. This study analyzed data from 77 patients with carbapenem-resistant Klebsiella pneumoniae infections. Among the samples, 63 K. pneumoniae isolates had MIC values of 1.0βmg/L as measured by broth microdilution but 0.5βmg/L as measured using the Vitek 2 system. Polymyxin B AUC/MIC was significantly associated with clinical response (pβ=β0.002) but not with 30-day all-cause mortality (pβ=β0.054). With a target AUC/MIC value of 50, Monte Carlo simulations showed that a fixed dose of 100βmg/12βh and three weight-based regimens (1.25βmg/kg/12βh for 80βkg and 1.5βmg/kg/12βh for 70βkg/80βkg) achieved a cumulative fraction of response >90% regardless of renal function, but the risk of nephrotoxicity was high. For patients with carbapenem-resistant K. pneumoniae infections, the underestimation of polymyxin resistance in automated systems need to be taken into account when optimizing polymyxin B dosing based on pharmacokinetic/pharmacodynamic principles
Alkali resistant and conductive guanidinium-based anion-exchange membranes for alkaline polymer electrolyte fuel cells
Choline Dehydrogenase Polymorphism rs12676 Is a Functional Variation and Is Associated with Changes in Human Sperm Cell Function
Approximately 15% of couples are affected by infertility and up to half of these cases arise from male factor infertility. Unidentified genetic aberrations such as chromosomal deletions, translocations and single nucleotide polymorphisms (SNPs) may be the underlying cause of many cases of idiopathic male infertility. Deletion of the choline dehydrogenase (Chdh) gene in mice results in decreased male fertility due to diminished sperm motility; sperm from Chdhβ/β males have decreased ATP concentrations likely stemming from abnormal sperm mitochondrial morphology and function in these cells. Several SNPs have been identified in the human CHDH gene that may result in altered CHDH enzymatic activity. rs12676 (G233T), a non-synonymous SNP located in the CHDH coding region, is associated with increased susceptibility to dietary choline deficiency and risk of breast cancer. We now report evidence that this SNP is also associated with altered sperm motility patterns and dysmorphic mitochondrial structure in sperm. Sperm produced by men who are GT or TT for rs12676 have 40% and 73% lower ATP concentrations, respectively, in their sperm. rs12676 is associated with decreased CHDH protein in sperm and hepatocytes. A second SNP located in the coding region of IL17BR, rs1025689, is linked to altered sperm motility characteristics and changes in choline metabolite concentrations in sperm
Recommended from our members
An International Comparative Study in the Relationship Between Academic Research and Teaching
Preface: celebrating the 60th anniversary of the University of Science and Technology of China
- β¦