Experimental Investigation of Regenerated Cellulose Microdialysis Probe Sterilization.

Sterilization of devices is important in hospitals, operating theatres, and emergency rooms. Microdialysis allows in vivo sampling of small molecules and is used for clinical studies. Microdialysis probes are made of soft, flexible, porous polymeric membranes.

Time-course concentration of ethanol, acetaldehyde and acetate in rat brain dialysate following alcohol self-administration.

The unclear mechanisms of ethanol metabolism in the brain highlight the need for a deeper understanding of its metabolic pathways. This study used in vivo microdialysis to simultaneously sample ethanol and its metabolites, acetaldehyde and acetate, in the rat striatum following self-administration of ethanol, emphasizing the natural oral exposure route. To enhance the self-administration, rats underwent two-bottle-choice and limited access training.

Experimental and numerical investigation of microdialysis probes for ethanol metabolism studies.

Microdialysis is an important technique for sampling of tissue's biochemical composition. Understanding the factors that affect the performance of the microdialysis probes and developing methods for sample analysis are crucial for obtaining reliable results. In this work, we used experimental and numerical procedures to study the performance of microdialysis probes having different configurations, membrane materials and dimensions.

Quantification of pyruvate in-vitro using mid-infrared spectroscopy: Developing a system for microdialysis monitoring in traumatic brain injury patients.

Introduction: Complex metabolic disruption is a major aspect of the pathophysiology of traumatic brain injury (TBI). Pyruvate is an intermediate in glucose metabolism and considered one of the most clinically informative metabolites during neurocritical care of TBI patients, especially in deducing the lactate/pyruvate ratio (LPR) - a widely-used metric for probing the brain's metabolic redox state. LPR is conventionally measured offline on a bedside analyzer, on hourly accumulations of brain microdialysate.

Infrared spectroscopy for neurochemical monitoring of alcohol and its metabolites.

Continuous measurement of the concentrations of ethanol and its metabolites, acetaldehyde and acetic acid, is important for the alcohol research community. Most studies only measure ethanol because accurate measurement of all three compounds is challenging. Measurement inside tissue/brain is done using a microdialysis technique, followed by off-line analysis using gas chromatography (GC).

Sorption Kinetics and Sequential Adsorption Analysis of Volatile Organic Compounds on Mesoporous Silica.

Adsorption-desorption behaviors of polar and nonpolar volatile organic compounds (VOCs), namely, isopropanol and nonane, on mesoporous silica were studied using optical reflectance spectroscopy. Mesoporous silica was fabricated via electrochemical etching of silicon and subsequent thermal oxidation, resulting in an average pore diameter of 11 nm and a surface area of approximately 493 m/g. The optical thickness of the porous layer, which is proportional to the number of adsorbed molecules, was measured using visible light reflectance interferometry.

Parametric study of a microdialysis probe and study of depletion effect using ethanol as a test analyte.

Although microdialysis is a common in vivo sampling technique, a detailed characterization of the performance of a microdialysis probe used for sampling ethanol molecules has not been conducted. In this work, experimental and computational investigations were carried out to quantitatively study ethanol diffusion characteristics for home-made and commercially available probes. Probe efficiency, i.

Point-of-care and self-testing for potassium: recent advances.

Potassium is an important bodily electrolyte which is kept within tight limits in health. Many medical conditions as well as commonly-used drugs either raise or lower blood potassium levels, which can be dangerous or even fatal. For at-risk patients, frequent monitoring of potassium can improve safety and lifestyle, but conventional venous blood draws are inconvenient, don't provide a timely result and may be inaccurate.

[Treatment-Emergent Central Sleep Apnea - Detection and Treatment].

Treatment-Emergent Central Sleep Apnea - Detection and Treatment In treatment-emergent central sleep apnea (TECSA), affected patients with obstructive sleep apnea newly develop central sleep apnea (AHI central ≥5/h) under therapy with positive pressure ventilation which cannot be explained by other causes. The pathophysiology of TECSA is incompletely understood. PaCO2 and the associated apnea threshold seem to play a central role.

Monitoring Neurochemistry in Traumatic Brain Injury Patients Using Microdialysis Integrated with Biosensors: A Review.

In a traumatically injured brain, the cerebral microdialysis technique allows continuous sampling of fluid from the brain's extracellular space. The retrieved brain fluid contains useful metabolites that indicate the brain's energy state. Assessment of these metabolites along with other parameters, such as intracranial pressure, brain tissue oxygenation, and cerebral perfusion pressure, may help inform clinical decision making, guide medical treatments, and aid in the prognostication of patient outcomes.

Review of Multifunctional Separators: Stabilizing the Cathode and the Anode for Alkali (Li, Na, and K) Metal-Sulfur and Selenium Batteries.

Alkali metal batteries based on lithium, sodium, and potassium anodes and sulfur-based cathodes are regarded as key for next-generation energy storage due to their high theoretical energy and potential cost effectiveness. However, metal-sulfur batteries remain challenged by several factors, including polysulfides' (PSs) dissolution, sluggish sulfur redox kinetics at the cathode, and metallic dendrite growth at the anode. Functional separators and interlayers are an innovative approach to remedying these drawbacks.

Selective Detection of Volatile Organics in a Mixture Using a Photoionization Detector and Thermal Desorption from a Nanoporous Preconcentrator.

The selective detection of individual hazardous volatile organic compounds (VOCs) within a mixture is of great importance in industrial contexts due to environmental and health concerns. Achieving this with inexpensive, portable detectors continues to be a significant challenge. Here, a novel thermal separator system coupled with a photoionization detector has been developed, and its ability to selectively detect the VOCs isopropanol and 1-octene from a mixture of the two has been studied.

Multifunctional Separator Allows Stable Cycling of Potassium Metal Anodes and of Potassium Metal Batteries.

This is the first report of a multifunctional separator for potassium-metal batteries (KMBs). Double-coated tape-cast microscale AlF on polypropylene (AlF @PP) yields state-of-the-art electrochemical performance: symmetric cells are stable after 1000 cycles (2000 h) at 0.5 mA cm and 0.

Cerebral Microdialysate Metabolite Monitoring using Mid-infrared Spectroscopy.

The brains of patients suffering from traumatic brain-injury (TBI) undergo dynamic chemical changes in the days following the initial trauma. Accurate and timely monitoring of these changes is of paramount importance for improved patient outcome. Conventional brain-chemistry monitoring is performed off-line by collecting and manually transferring microdialysis samples to an enzymatic colorimetric bedside analyzer every hour, which detects and quantifies the molecules of interest.

Temporally resolved thermal desorption of volatile organics from nanoporous silica preconcentrator.

Detection and separation of gas-phase volatile organic compounds (VOCs) is of great importance for many applications including air quality monitoring, toxic gas detection and medical diagnostics. A lack of small and low-cost detectors limits the potential applications of VOC gas sensors, especially in the areas of consumer products and the 'Internet of Things'. Most of the commercially available low-cost technologies are either only capable of measuring a single VOC type, or only provide a total VOC concentration, without the ability to provide information on the nature or type of the VOC.

Nanoporous Silica Preconcentrator for Vapor-Phase DMNB, a Detection Taggant for Explosives.

The detection of trace amounts of explosives in the vapor phase is of great importance. Preconcentration of the analyte is a useful technique to lower the detection limit of existing sensors. A nanoporous silica (pSiO) substrate was evaluated as a preconcentrator for gas-phase 2,3-dimethyl-2,3-dinitrobutane (DMNB), a volatile detection taggant added by law to plastic explosives.

DeSignate: detecting signature characters in gene sequence alignments for taxon diagnoses.

Background: Molecular characters have been added in integrative taxonomic approaches in recent years. Nevertheless, taxon diagnoses are still widely restricted to morphological characters. The inclusion of molecular characters into taxon diagnoses is not only hampered by problems, such as their definition and the designation of their positions in a reference alignment, but also by the technical effort.

A Link is not Enough - Reproducibility of Data.

Although many works in the database community use open data in their experimental evaluation, repeating the empirical results of previous works remains a challenge. This holds true even if the source code or binaries of the tested algorithms are available. In this paper, we argue that providing access to the raw, original datasets is not enough.

Mid-IR evanescent-field fiber sensor with enhanced sensitivity for volatile organic compounds.

The increasing awareness of the harsh environmental and health risks associated with air pollution has placed volatile organic compounds (VOCs) sensor technologies in elevated demand. While the currently available VOC-monitoring technologies are either bulky and expensive, or only capable of measuring a total VOC concentration, the selective detection of VOCs in the gas-phase remains a challenge. To overcome this, a novel method and device based on mid-IR evanescent-wave fiber-optic spectroscopy, which enables enhanced detection of VOCs, is hereby proposed.

Diagnostic and prognostic value of plasma volume status at emergency department admission in dyspneic patients: results from the PARADISE cohort.

Background: Systemic congestion, evaluated by estimated plasma volume status (ePVS), is associated with in-hospital mortality in acute heart failure (AHF). However, the diagnostic and prognostic value of ePVS in patients with acute dyspnea has been insufficiently studied.

Objectives: To assess the association between the first ePVS calculated from blood samples on admission in the emergency department (ED) and discharge diagnosis of AHF and in-hospital mortality in patients admitted for acute dyspnea.

Impedance-based sensor for potassium ions.

A conductometric sensor for potassium ions in solution is presented. Interdigitated, planar gold electrodes were coated with a potassium-selective polymer membrane composed of a poly(vinyl chloride) matrix with about 65 wt% of plasticiser and 2-5 wt% of a potassium-selective ionophore. The impedance of the membrane was measured, using the electrodes as a transducer, and related to the concentration of potassium in a sample solution in contact with the membrane.

Optical fibre-tip probes for SERS: numerical study for design considerations.

Enhancement of sub-wavelength optical fields using sub-micron plasmonic probes has found many applications in chemical, material, biological and medical sciences. The enhancement is via localised surface-plasmon resonance (LSPR) which enables the highly sensitive vibrational-spectroscopy technique of surface-enhanced Raman scattering (SERS). Combining SERS with optical fibres can allow the monitoring of biochemical reactions in situ with high resolution.

Tuning plasmons layer-by-layer for quantitative colloidal sensing with surface-enhanced Raman spectroscopy.

Surface-enhanced Raman spectroscopy (SERS) is well known for its high sensitivity that emerges due to the plasmonic enhancement of electric fields typically on gold and silver nanostructures. However, difficulties associated with the preparation of nanostructured substrates with uniform and reproducible features limit reliability and quantitation using SERS measurements. In this work we use layer-by-layer (LbL) self-assembly to incorporate multiple functional building blocks of collaborative assemblies of nanoparticles on colloidal spheres to fabricate SERS sensors.

Relevant pericardial effusion caused by cytomegalovirus infection in an immunocompetent patient: a case report.

Background: Cytomegalovirus infection is known to cause symptomatic disease in immunocompromised patients, while an infection in immunocompetent individuals normally causes few or no symptoms. We present the case of an immunocompetent adult patient with unexpected severe evolution.

Case Presentation: An otherwise healthy, 72-year-old Caucasian woman presented with complaints of progressive shoulder pain and dyspnoea on exertion.

Development of an open technology sensor suite for assisted living: a student-led research project.

Many countries have a rapidly ageing population, placing strain on health services and creating a growing market for assistive technology for older people. We have, through a student-led, 12-week project for 10 students from a variety of science and engineering backgrounds, developed an integrated sensor system to enable older people, or those at risk, to live independently in their own homes for longer, while providing reassurance for their family and carers. We provide details on the design procedure and performance of our sensor system and the management and execution of a short-term, student-led research project.