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A single-centre interrupted time series quasi-experimental study was undertaken to assess whether a hospital policy of selective digestive decontamination (SDD, gentamicin/amikacin with neomycin) administered to carbapenem-resistant Enterobacterales (CRE) carriers would reduce the duration of carriage and contain the spread of CRE. No significant difference in time to CRE eradication was observed between the observation (12 months, 120 patients) and intervention (12 months, 101 patients) periods. No change in the trend of new in-hospital CRE acquisitions or bacteraemia during the intervention was detected. As such, administration of SDD to CRE carriers was not effective for the eradication of carriage or controlling in-hospital CRE transmissions.

One of the most frequently prescribed selective serotonin reuptake inhibitor medications (SSRIs) for peripartum mood and anxiety disorders is sertraline (Zoloft®). Sertraline can help alleviate mood and anxiety symptoms in many women but it is not known how sertraline, or SSRIs in general, affect the neurobiology of the brain particularly when pregnant. The aim of this study was to investigate how sertraline affects plasticity in the hippocampus, a brain area integral in depression and SSRI efficacy (particularly in males), during late pregnancy and whether these effects differ from the effects of sertraline in non-pregnant females. To do this pregnant and age-matched non-pregnant female Sprague-Dawley rats were used. For the last half of pregnancy (10 days), and at matched points in non-pregnant females, rats were given sertraline (2.5 mg/kg/day or 10 mg/kg/day) or vehicle (0 mg/kg/day). Brains were used to investigate effects on the serotonergic system in the hippocampus and prefrontal cortex and measures of neuroplasticity in the hippocampus. Results show that pregnant females have significantly higher serum levels of sertraline compared to non-pregnant females but that rates of serotonin turnover in the hippocampus and PFC are similar between pregnant and non-pregnant females. Sertraline increased synaptophysin density in the dentate gyrus and CA3 and was associated with a decrease in cell proliferation in the dentate gyrus of non-pregnant, but not pregnant, females. During late pregnancy the hippocampus showed significant reductions in neurogenesis and increases in synaptophysin density. This research highlights the need to consider the unique effect of reproductive state on the neuropharmacology of SSRIs. © 2020 Elsevier Ltd

This document describes monitoring features related to media streams in Web real-time communication (WebRTC). It provides a list of RTCP Sender Report, Receiver Report and Extended Report metrics, which may need to be supported by RTP implementations in some diverse environments. It lists a set of identifiers for the WebRTC's statistics API. These identifiers are a set of RTCP SR, RR, and XR metrics related to the transport of multimedia flows.

Electrochemical insertion of lithium into pyrolyzed amorphous carbons prepared from polymeric precursors of methacrylonitrile and divinylbenzene has been investigated by 7Li variable temperature static and magic angle spinning (MAS) NMR. This method is able to characterize the chemical inventory of lithium, differentiating between reversible species that are truly inserted into the carbon and irreversible species that are lost to traps and parasitic processes. Furthermore, large chemical shift effects indicate that the structural and electronic properties of the inserted reversible lithium species are sensitively dependent on the extent of loading. At loading levels ≤90% relative capacity, the trend is monotonic, whereas in more highly charged samples, two types of electrochemically relevant sites are observed, distinguishable from one another only at lower temperatures. At higher temperatures, dynamic exchange effects between them are evident on the NMR time scale. In the initially prepared state, these ...

The rapid increase in mobile phone use in young people has generated concern about pos- sible health effects of exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF). MOBI-Kids, a multinational case-control study, investigates the potential effects of childhood and adolescent exposure to EMF from mobile communi- cations technologies on brain tumor risk in 14 countries. The study, which aims to include approximately 1,000 brain tumor cases aged 10-24 years and two individually matched controls for each case, follows a common protocol and builds upon the methodological experience of the INTERPHONE study. The design and conduct of a study on EMF expo- sure and brain tumor risk in young people in a large number of countries is complex and poses methodological challenges.This manuscript discusses the design of MOBI-Kids and describes the challenges and approaches chosen to address them, including: (1) the choice of controls operated for suspected appendicitis, to reduce potential selection bias related to lowresponse rates among population controls; (2) investigating a young study population spanning a relatively wide age range; (3) conducting a large, multinational epidemiologi- cal study, while adhering to increasingly stricter ethics requirements; (4) investigating a rare and potentially fatal disease; and (5) assessing exposure to EMF from communication technologies. Our experience in thus far developing and implementing the study protocol indicates that MOBI-Kids is feasible and will generate results that will contribute to the understanding of potential brain tumor risks associated with use of mobile phones and other wireless communications technologies among young people. © 2014.

The oxidizing agent tris(bipyridyl)ruthenium(III), or Ru-(bpy)(3)3+, is used as a postcolumn reagent for the detection of nitroaromatic and nitramine explosive compounds. After separation, the explosives are reduced electrochemically to oxidizable products such as hydroxlamines and nitrosamines, and these products react readily with Ru-(bpy)(3)3+ and Ru(bpy)(3)2+. The photoluminescence from the latter is used for detection. A porous carbon electrode was used for on-line analyte reduction following chromatography. Another porous carbon electrode was used to generate the nonluminescent Ru(bpy)(3)3+ from Ru(bpy)(3)3+ on-line at high efficiency. The two streams were combined, and the Ru(bpy)(3)2+ produced by oxidation of the reduced analytes was detected by laser illumination and light detection. Reductive hydrodynamic voltammograms of nitrobenzene, 2,4,6-trinitrotoluene, and hexahydro-1,3,5-trinitro-1,3,5-triazine indicated that a potential of - 1500 mV vs Ag/AgCl was sufficient to achieve a maximum signal from the reduced analytes. HPLC with a water/acetonitrile gradient on a C-18 reversed-phase column was then used to determine these three compounds plus the four additional examples, 1,3,5,7-tetrazocine, 2,4-dinitrotoluene; 2,6-dinitrotoluene, and 4-nitrotoluene. For both hydrodynamic voltammetry and HPLC detection, the photoluminescence following electron-transfer signal was calibrated using the one-electron standards ferrocene and ferrocenecarboxylic acid. Detection limits were in the low-nanomolar range for 20-microL injections of nonpreconcentrated nitro compounds.

Single electron devices are of great interest for their possible replacement of transistors in memories. The key to the preparation of these components is the production of low capacitance dots, which requires a lithography step at nanometric scale. Direct patterning of metallic features at nanometric scale is possible by local decomposition of gaseous molecules under a scanning tunneling microscope (STM) tip, by application of a voltage of a few volts on the sample (STM assisted chemical vapour deposition). The gaseous molecules are dissociated by the high electric field (about 107 V/cm) within the tip–sample gap. Rhodium lines and dots have been deposited on gold or silicon surfaces by decomposition of [Rh(PF3)2Cl]2. The influence of the sample voltage was studied and the resolution limit of the technique was investigated.

Direct patterning of nanometric metallic features is possible by local decomposition of gaseous molecules on a surface, induced by application of a pulse voltage on a STM tip while surface imaging. Decomposition reaction occurs above a threshold voltage of 2.7 V corresponding to an electric field of about 5.4 10 7 V.cm -1 between STM tip and sample. Metallic Rhodium dots as small as 3 nm can be deposited using this method. The kinetics of formation of these dots are discussed and a reaction mechanism is proposed.

Tris(2,2'-bipyridyl)ruthenium can be excited to fluorescence by visible light (lambda abs 454 nm, lambda em 607 nm) when in the M(II) oxidation state, but not in the M(III) state. A novel chromatographic detection method using the non-fluorescent M(III) form of the complex as a postcolumn fluorogenic reagent is demonstrated. The M(III) form is a powerful oxidizing agent (E degree = 1.27 V vs NHE, 1.05 V vs Ag/AgCl). The M(III) reagent is generated on-line from the M(II) form of the complex by a highly efficient porous carbon electrode and then reacted briefly with chromatographic effluent; the M(II) created by electron transfer from oxidation-susceptible analytes is then detected by fluorescence. The fluorescence detector can be calibrated for number of electrons transferred by injection of either M(II) or an oxidative standard such as ferrocyanide. It is hoped that this redox-based detection scheme will provide an alternative to electrochemical detection. Among the advantages are freedom from surface fouling and the potential for extremely low detection limits. The scheme was applied to detection of the peptide dynorphin A and several of its fragments. Dynorphin A contains tyrosine at the N-terminus (position 1) and tryptophan in position 15; these amino acid residues are susceptible to oxidation and peptides containing them can be detected on that basis. Flow injection testing of the model compounds Tyr-Gly-Gly-Phe-Leu and Gly-Gly-Trp-Gly indicated that tyrosine transferred approximately 1 electron to the M(III) reagent and that tryptophan transferred approximately 4 electrons. Similar results were obtained from the chromatographic runs. Dynorphin A and six dynorphin A fragments containing the N-terminal tyrosine were detected easily at 100 nM concentration (14 pmol) using laser-induced fluorescence. As expected, one fragment that did not contain tryptophan or tyrosine was not detected. A mass detection limit of 80 fmol was estimated for the tyrosine-containing fragments.

This paper deals with two techniques for improvement of ultrasonic images interpretation based on image and digital signal processing. The first technique concerns image processing. We propose an analytical model to evaluate the effective Point Spread Function (PSF) of a reflection scanning ultrasonic system. We present the great interest of the knowledge of the PSF for deconvolution of ultrasonic images based on Lucy-Richardson algorithm. With this technique, lateral resolution is strongly improved and real dimensions of an object can be reached that is necessary to improve the understanding and interpretation of an image. The second technique concerns ultrasonic images showing different nature of defects. A better understanding of these images can be realized by means of time of flight detection. This technique concerns Time-Frequency (TF) analysis to determine nature and depth of defects with accuracy. Two applications of microassembling die-attach characterisation are presented using these methods.

Multinuclear solid-state NMR spectroscopy is a well-suited technique for structural analysis of amorphous carbon-based anode materials generated from pyrolysis of poly(methacrylonitrile/divinylbenzene) copolymers. Results are presented for the untreated polymeric precursor, the oxidatively stabilized material, and amorphous carbons prepared by high-temperature pyrolysis. In addition, structural effects of silicon dopants and lithium intercalants are studied. The structural changes occurring during the processes of oxidative stabilization and carbonization up to 700 °C are effectively monitored by 13C and 15N cross-polarization/magic angle spinning methods. The peak assignments are assisted by short contact time and dipolar dephasing experiments. For carbons prepared at higher pyrolysis temperatures this technique is limited by the low structural proton content. For such materials, the 1H chemical shifts of sorbed water molecules are found to be linearly correlated with the pyrolysis temperature. This effe...

Porous polymeric foams are well-known materials and have been produced by a wide variety of techniques ranging from leaching soluble fillers through gas-blowing to phase separation. Although these materials are widely used, their structure is often irregular and difficult to control. However, a novel method for producing porous materials with a more regular structure has been developed based on high internal phase emulsions (HIPE). These foams are called emulsion-derived foams and are commercially known as Polyhipe® (Unilever) polymers.If one takes a liquid oil, introduces water and a suitable emulsifier with agitation, a dilute emulsion is produced with small water droplets dispersed within the oil phase, about the consistency of milk. If the amount of the water (i.e., the internal or pore forming) phase is increased, a concentrated emulsion will be formed and the consistency of the mixture changes into a more viscous fluid. As further water is introduced, a limit is reached where the droplets are so prevalent that they approximate a close-packed structure (see cover of this issue); beyond this point the droplets must distort to accommodate any additional internal phase. For a collection of monodispersed spheres this packing limit corresponds to 74% by volume and is the accepted definition of a high internal phase emulsion, i.e., an emulsion with an internal phase greater than 74%.4 The structure of the emulsion is now analogous to soap bubbles, with thin films surrounding and separating the drops. Note also that, compared to “standard” emulsion polymerization, this is the exact reverse or “inverse” of that process. In the standard route, the dispersed oil phase is polymerized to yield a collection of polymeric spheres; with inverse emulsion, the continuous phase is polymerized, yielding a rigid matrix.

The bisphthalocyanine of lutetium, Pc2Lu, is the first intrinsic molecular semiconductor, with a high concentration of intrinsic charge carriers and a low thermal activation energy of conduction. The redox potentials of Pc2Lu, which is more easily oxidized and reduced than conventional metal phthalocyanines, make it possible to obtain the intrinsic semiconducting properties. The possibility of using Pc2Lu as the sensitive element of a gas sensor is studied. This paper describes the absorption spectra of thin films of Pc2Lu and their changes during oxidation or reduction induced by gases such as HCl, Cl2, H2S and SO2. Special attention is given to the action of NO2 on the conductivity and the corresponding thermal activation energy, whose evolution is interpreted in terms of variations of carrier concentration and mobility.

Mirage detection has been used to monitor the flux of counter-ions between an electrode of lutetium diphthalocyanine (Pc2Lu) and an aqueous electrolyte during voltammetric experiments. The direction of the deflection of a laser probe, related to the concentration gradient near the electrode, shows whether the counter-ions enter or exit the film. Evidence for the mechanism of transfer between the electrode and solution is then obtained directly. The concentration mirage effect shows that the redox reactions of the film in contact with neutral KCl correspond to simple transfers: and and not to the complex mechanism proposed previously. In acidic medium (HA), we confirmed the first step starting from a virgin electrode, i.e. incorporation of the anion A− of the acid for charge compensation. But the simple mechanism of the stationary voltammograms: , HA had to be replaced by a two-step equilibrium: .

The adsorption of polystyrene onto noble metals from 3.3% solutions in five different theta solvents was measured on six noble metals at temperatures a few degrees above the theta temperatures. The amounts adsorbed (in mg m −2 ) on any given metal were of the same order of magnitude from all five of the theta solvents, but decreased two or three orders of magnitudes with a change of noble metals, in the following order: gold⪢silver⪢palladium, silver-palladium ⪢platinum⪢iridium. The amounts adsorbed on gold from cyclohexane at 60°C decreased seven-fold with a forty-fold decrease of molecular weight, as predicted by Scheutjens and Fleer, but there was no molecular weight dependence to the weak adsorption observed on platinum and iridium. A direct method was used to determine the amount of polymer adsorbed on these metal powders. After the polymer solution and metal powder were equilibrated, the powder was washed free of excess polymer solution with fresh theta solvent and then the adsorbed polystyrene was removed from the metal by rinsing in chloroform, a very good solvent, in which the amount of polystyrene was determined by UV spectroscopy. With the high molecular weight polystyrene (1.8·10 6 ) the differences in duplicate samples were about 2%, but with the lower molecular weight polystyrene (5·10 4 ) they were about 25%. It is proposed that the high reproducibility of adsorption results observed with the high molecular weight polymer indicates negligible desorption during rinsing with the theta solvent, but that this rinsing step was less reproducible with the low molecular weight polymer.