Although water's chemical properties are no less important than its exceptional physical properties, its acid-base behavior is relatively poorly understood. In fact, the Grotthus trajectories for ion recombination predicted by density functional theory do not comport well with the almost 100-fold slower diffusive trajectories observed in time-resolved spectroscopy. And, in the reverse reaction, the barrier to autoionization is not well characterized. Here we develop a self-consistent picture of both processes based on the occurrence and role of ultrashort hydrogen bonds. The predicted populations of these special pairs in bulk water are consistent with the high frequency electrodynamics of water and its pressure dependence. The rate-limiting role of the special pairs manifests in autoionization as a two-stage barrier, first to form a contact ion pair and then to separate it by one water molecule. From this configuration, similar frequencies are observed for further separation vs recombination. The requirement of ultrashort hydrogen bonds for proton transfer in autoionization is consistent with the rise in K with increasing pressure and points to a role for density fluctuations in autoionization events. In neutralization, the manifestation of the role of special pairs is the prolonged diffusional process observed in time-resolved spectroscopy experiments. The requirement of special pairs as transition states for proton transfer is less obvious for neutralization in isolated water chains than in the bulk liquid only because an unbroken sequence of ultrashort H-bonds is more easily formed in a 1D H-bonded chain than in a 3D H-bonded network.
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http://dx.doi.org/10.1021/acs.jpcb.7b02110 | DOI Listing |
J Ophthalmic Inflamm Infect
January 2025
School of Medicine, National Taiwan University, Taipei, Taiwan.
Purpose: To identify the macular retinal layer thickness changes in polyarteritis nodosa (PAN) patients without pathological findings appearing in color fundus photography (CFP), and to investigate the correlations with disease durations.
Methods: A total of 24 PAN patients who had been for 3 years or more and underwent SD-OCT were recruited from the UK Biobank, with exclusions for diabetes, eye disease, or abnormal CFP findings. Only the right eyes were included, with each PAN patient paired one-to-one with a control matched for age, sex, and ethnicity.
Background: Pediatric ultrasound (US)-guided percutaneous liver biopsy is a commonly performed procedure in children, and may be performed in a variety of clinical settings. However, there is little research on the relative costs associated with different sedation methods and locations.
Objective: This study uses time-driven activity-based costing (TDABC) to identify relevant costs associated with different biopsy sedation techniques and locations to help inform providers and patients as well as guide value-conscious care.
Hum Mol Genet
January 2025
Department of Thoracic Surgery, Huaihe Hospital of Henan University, No. 8, Baobei Road, Gulou District, Kaifeng City, Henan Province, China.
Adenocarcinoma of the esophagogastric junction (AEG) is a common and deadly cancer, and an in-depth investigation of its molecular mechanisms of metastasis is crucial for discovering new therapeutic targets. This study explores the role of the long non-coding RNA (lncRNA) LINC00115 in AEG metastasis and its underlying mechanisms. Through the analysis of 108 pairs of AEG cancer tissues and matched adjacent tissues, we found a significant upregulation of LINC00115 in AEG tissues, closely associated with TNM staging and lymph node metastasis.
View Article and Find Full Text PDFGenet Med
January 2025
Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada; BC Children's Hospital Research Institute, Vancouver, BC, Canada; Women's Health Research Institute, Vancouver, BC, Canada. Electronic address:
Purpose: The increasing complexity of genetic technologies paired with more genetic tests being ordered by nongenetic healthcare providers, has resulted in an increase in the number of inappropriately ordered tests. Genetic counselors (GCs) are ideally suited to assess the appropriateness of a genetic test.
Methods: We performed a scoping review of GC involvement in utilization management initiatives in order to describe the impact of having GCs involved in this process.
Curr Med Res Opin
January 2025
Department of Pediatrics and Adolescent Medicine, Lillebaelt Hospital, University Hospital of Southern Denmark, Kolding, Denmark.
Objective: The symptom burden associated with allergic rhinitis (AR) negatively impacts the life of people living with the condition. Although the impact of AR on educational outcomes and the effect of AR-relieving medication have been investigated, the availability of up-to-date, population-based, real-world evidence is limited. Therefore, the aim was to investigate the impact of AR and AR-relieving medication on educational outcomes.
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