The chromatographic properties of high pressure high temperature synthesised diamond (HPHT) are investigated under the conditions of hydrophilic interaction liquid chromatography (HILIC). A 50×4.6mm ID stainless steel column packed with HPHT particles of mean diameter 1.6μm and specific surface area 5.1mg is used. According to the results of acid-base titration with NaOH the purified HPHT batch contains 4.59μeqg of protogenic, mainly carboxyl- and hydroxyl-, groups, which make this polar adsorbent suitable for use as a stationary phase in HILIC. The retention behaviour of several classes of polar compounds including benzoic and benzenesulfonic acids, nitro- and chlorophenols, various organic bases, and quaternary ammonium compounds are studied using acetonitrile and methanol based mobile phases containing 5-30v/v% of water. The effects of the buffer pH and concentration, column temperature and organic solvent content on retention of model compounds are also investigated. It is shown that both pH and acetonitrile/methanol ratio in the mobile phase can be used to vary the separation selectivity. Molecular adsorption mechanism (related to aqueous normal phase mode), rather than partitioning is established to be responsible for the retention.
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http://dx.doi.org/10.1016/j.chroma.2016.09.076 | DOI Listing |
Arterioscler Thromb Vasc Biol
January 2025
Department of Medicine, Leon H. Charney Division of Cardiology (S.Z., B.-X.L., A.C., M.F., E.A.F., S.P.H.).
Background: Cholesterol efflux capacity (CEC) of HDL (high-density lipoprotein) is inversely associated with incident cardiovascular events, independent of HDL cholesterol. Obesity is characterized by low HDL cholesterol and impaired HDL function, such as CEC. Bariatric surgery, including Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), broadly leads to improved cardiovascular outcomes, but impacts on risk factors differ by procedure, with greater improvements in weight loss, blood pressure, and glycemic control after RYGB, but greater improvements in HDL cholesterol and CEC levels after SG.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430071, China.
Photodynamic therapy (PDT) holds great potential in cancer treatment, leveraging photosensitizers (PSs) to deliver targeted therapy. Fluorination can optimize the physicochemical and biological properties of PSs for better PDT performance. Here, we report some high-performance multifunctional PSs specifically designed for cancer PDT by fluorinating aza-BODIPY with perfluoro--butoxymethyl (PFBM) groups.
View Article and Find Full Text PDFFront Physiol
December 2024
Department of Health Sciences, Public University of Navarre (UPNA), Pamplona, Spain.
In this quasi-experimental before-after trial, we investigated the effects of a high-intensity, low-repetition inspiratory muscle training (HI-LRMT) protocol on respiratory muscle strength in instrumental musicians. In addition, was to estimate the prevalence of "non-responders" (NRs) in terms of muscle force after intervention. Healthy musicians ( = 48) were divided into 2 groups: HI-LRMT ( = 33) and a control group that did not train (CG, = 15).
View Article and Find Full Text PDFFront Cardiovasc Med
December 2024
Departamento Medicina Interna, Hospital Lusíadas Lisboa, Lisboa, Portugal.
Introduction: This study aims to characterize the cardiovascular risk profile in countries with low-to-moderate cardiovascular mortality risk (Italy, Portugal, France, and Spain) using the SCORE2 and SCORE2-OP models. It also examines regional variations and the involvement of healthcare professionals in performing risk assessments.
Methods: A retrospective observational study was conducted using data from 24,434 cardiovascular risk assessments performed between December 2022 and July 2023 through a digital application used by physicians.
Anal Chem
January 2025
School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian 116024, Liaoning, China.
A cantilever-enhanced fiber-optic photoacoustic (PA) spectrophone is reported for trace gas detection at a low-pressure environment. A cantilever-based fiber-optic Fabry-Perot (F-P) interferometer (FPI) is utilized for simultaneous measurement of air pressure and PA pressure. Since the cantilever resonance frequency follows air pressure linearly, the fundamental frequency intensity modulation (1-IM) technique is applied to scan the frequency response of the solid PA signal from tube wall absorption for tracking the cantilever resonance frequency in real time.
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