Boron Doped Diamond Electrodes for Direct Measurement in Biological Fluids: An In Situ Regeneration Approach

International audienceBoron doped diamond (BDD) electrodes are extremely promising in the field of biomedical applications as they exhibit a unique combination of properties. Despite these advantages, BDD electrodes are prone to fouling when used in biological fluids (urine, blood plasma), and synthetic fluids. We propose a electrochemical (EC) treatment where a train of short cathodic and/or anodic pulses are applied to clean fouled electrodes. This technique can be used to retrieve the lost reactivity, characterized by electron transfer rate k0 of the boron doped diamond electrodes, thereby enhancing their reusability over long period of measurements without degradation of the signal, thus significantly extending the field of monitoring and surveying applications. The technique does not require the use of a specific medium and thus can be directly performed in the probed fluid. Although an aqueous electrolyte containing non-electroactive species is preferred for EC activation, it can also be done in biological fluids such as blood, urine etc, thereby opening the field for $in-vivo$ analysis. Through Electrochemical impedance spectroscopy (EIS) it was observed that the k$_0$ value was increased up to 0.1 cm s$^{−1}$ after the activation process. This technique improves the sensitivity, reproducibility and lifetime of the electrodes to a considerable extent

The crime drop and the security hypothesis

Major crime drops were experienced in the United States and most other industrialised countries for a decade from the early to mid-1990s. Yet there is little agreement over explanation or lessons for policy. Here it is proposed that change in the quantity and quality of security was a key driver of the crime drop. From evidence relating to vehicle theft in two countries it is concluded that electronic immobilisers and central locking were particularly effective. It is suggested that reduced car theft may have induced drops in other crime including violence. From this platform a broader security hypothesis, linked to routine activity and opportunity theory, is outlined

Preventing phone theft and robbery: the need for government action and international coordination

The banning of stolen handsets from networks has been around for 20 years, but remains little used internationally. Where used, its effectiveness is hindered by implementation problems, reprogramming, easy fencing opportunities, and international trafficking. Kill-switches where the user remotely disables a handset and deletes data have potential but, if non-permanent, are likely to experience similar limitations. This study proposes a set of responses to be adopted by national governments with international coordination

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

IN SAFE HANDS: A Review of Mobile Phone Anti-theft Designs

Anti-theft designs relating to mobile phones are reviewed. The physical and electronic design of handsets includes visual deterrents, owner-identification, and handset tracking options. The systems design of phone networks includes the blacklisting of stolen phones. Other measures include biometric-locking of handsets, and designs that encourage ‘safe’ phone use and transportation. Characteristics that promote anti-theft designs are proposed and form the acronym ‘IN SAFE HANDS’: identifiable, neutral, seen, attached, findable, executable, hidden, automatic, necessary, detectable, and secure. The set of characteristics is presented as a heuristic device to aid designing-out crime from frequently stolen electronic goods

Electrochemistry provides a simple way to monitor Pseudomonas aeruginosa metabolites

Pseudomonas aeruginosa is one of the most common bacteria responsible for nosocomial infections. To imagine new therapies, understanding virulence mechanisms and the associated communication system of the bacterium (its quorum sensing) is a target of the first importance. Electrochemistry is a promising tool for real-time in situ monitoring of electroactive species issued from P. aeruginosa communication system. This contribution deals with the electrochemical characterization of the main bacteria electroactive metabolites: Pseudomonas Quinolone Signal, pyocyanin and 2′-aminoacetophenone. These metabolites were electrochemically characterized and further detected in supernatant of P. aeruginosa PA01 strain grown in LB medium

Referenceless pH Sensor using Organic Electrochemical Transistors

pH is an extremely important parameter in all biological and most chemical reactions. pH sensing has been specifically shown to be of paramount importance in many fields such as environmental science, sport, or healthcare as the acidosis or alkalinity of a solution is a marker of a physiological state. Indeed, pH variation can be indicative of lactate production during infection.[1] Besides, during intensive training, the con-centration of lactic acid in sweat increases,[2] decreasing by this way the pH of the sweat. The normal body pH value is different for each subject, which is why, in most cases, we want to detect variations of pH rather than its absolute value