A selected ion flow tube study of the ion-molecule reactions of monochloroethene, trichloroethene and tetrachloroethene

Data for the rate coefficients and product cations of the reactions of a large number of atomic and small molecular cations with monochloroethene, trichloroethene and tetrachloroethene in a selected ion flow tube at 298 K are reported. The recombination energy of the ions range from 6.27 eV (H$_3$O$^+$) through to 21.56 eV (Ne$^+$). Collisional rate coefficients are calculated by modified average dipole orientation theory and compared with experimental values. Thermochemistry and mass balance predict the most feasible neutral products. Together with previously reported results for the three isomers of dichloroethene (J. Phys. Chem. A., 2006, 110, 5760), the fragment ion branching ratios have been compared with those from threshold photoelectron photoion coincidence spectroscopy over the photon energy range 9-22 eV to determine the importance or otherwise of long-range charge transfer. For ions with recombination energy in excess of the ionisation energy of the chloroethene, charge transfer is energetically allowed. The similarity of the branching ratios from the two experiments suggest that long-range charge transfer is dominant. For ions with recombination energy less than the ionisation energy, charge transfer is not allowed; chemical reaction can only occur following formation of an ion-molecule complex, where steric effects are more significant. The products that are now formed and their percentage yield is a complex interplay between the number and position of the chlorine atoms with respect to the C=C bond, where inductive and conjugation effects can be important

A typology of modifications to peer support work for adults with mental health problems:systematic review

© The Authors 2020. Background Peer support work roles are being implemented internationally, and increasingly in lower-resource settings. However, there is no framework to inform what types of modifications are needed to address local contextual and cultural aspects. Aims To conduct a systematic review identifying a typology of modifications to peer support work for adults with mental health problems. Method We systematically reviewed the peer support literature following PRISMA guidelines for systematic reviews (registered on PROSPERO (International Prospective Register of Systematic Reviews) on 24 July 2018: CRD42018094832). All study designs were eligible and studies were selected according to the stated eligibility criteria and analysed with standardised critical appraisal tools. A narrative synthesis was conducted to identify types of, and rationales for modifications. Results A total of 15 300 unique studies were identified, from which 39 studies were included with only one from a low-resource setting. Six types of modifications were identified: role expectations; initial training; type of contact; role extension; workplace support for peer support workers; and recruitment. Five rationales for modifications were identified: to provide best possible peer support; to best meet service user needs; to meet organisational needs, to maximise role clarity; and to address socioeconomic issues. Conclusions Peer support work is modified in both pre-planned and unplanned ways when implemented. Considering each identified modification as a candidate change will lead to a more systematic consideration of whether and how to modify peer support in different settings. Future evaluative research of modifiable versus non-modifiable components of peer support work is needed to understand the modifications needed for implementation among different mental health systems and cultural settings. Declaration of interest None

Association between soy and green tea (Camellia sinensis) diminishes hypercholesterolemia and increases total plasma antioxidant potential in dyslipidemic subjects.

One hundred dyslipidemic individuals were allocated into four groups. The soy group ingested 50 g of soy (kinako) daily, and the green tea group ingested 3 g of green tea in 500 mL of water per day. A third group ingested 50 g of soy and 3 g of green tea daily, and the control group had a hypocholesterolemic diet. Evaluations were performed at baseline and after 45 and 90 d. Plasma levels of total cholesterol, high-density lipoprotein, and triacylglycerols were evaluated by automated methods. Low-density lipoprotein (LDL) cholesterol was calculated using the Friedewald equation. LDL was isolated by ultracentrifugation. Total plasma antioxidant capacity and plasma levels of total lipid hydroperoxides and those linked to LDL were evaluated by chemiluminescence. The results were expressed as median values and their 25th to 75th percentiles, with a 5% level of significance.Nome correto do segundo autor: MANDARINO, J. M. G

Development of instrumentation for amperometric and coulometric detection using ultramicroelectrodes

In this work it is presented the development of a simple, portable and inexpensive instrumentation for amperometric and coulometric detection in different analytical instrumentation systems utilizing ultramicroelectrodes. The software, developed in LabVIEW 7.1TM, is capable to carry out three main detection techniques (amperometric, pulsed amperometric and coulometric detection) and a voltammetric technique (cyclic voltammetry). The instrumentation was successfully evaluated using the following systems: cyclic voltammograms of metallic electrodes in alkaline solutions, flow electrochemical detection of glucose and glycine and direct determination of herbicide glyphosate (electrochemical detection coupled to HPLC).Neste trabalho é apresentado o desenvolvimento de uma instrumentação simples, portátil e de baixo custo para detecção amperométrica e coulométrica usando ultramicroeletrodos em diferentes sistemas analíticos. O programa, desenvolvido em LabVIEW 7.1TM, é capaz de realizar três modos de detecção (amperométrico, coulométrico e amperométrico pulsado) e voltametria cíclica. A instrumentação desenvolvida foi avaliada utilizando os seguintes sistemas: voltametria cíclica de eletrodos metálicos em solução alcalina, detecção eletroquímica em fluxo de glicose e glicina, e também na determinação direta do herbicida glifosato (detecção eletroquímica aliada à cromatografia líquida de alta eficiência, CLAE)

Fuzzy modelling of acid mine drainage environments using geochemical, ecological and mineralogical indicators

Fuzzy logic was applied to model acid mine drainage (AMD) and to obtain a classification index of the environmental impact in a contaminated riverine system. The data set used to develop this fuzzy model (a fuzzy classifier) concerns an abandoned mine in Northern Portugal— Valdarcas mining site. Here, distinctive drainage environments (spatial patterns) can be observed based on the AMD formed in the sulphide-rich waste-dumps. Such environments were established, as the effluent flows through the mining area, using several kinds of indicators. These are physical–chemical, ecological and mineralogical parameters, being expressed in a quantitative or qualitative basis. The fuzzy classifier proposed in this paper is a min– max fuzzy inference system, representing the spatial behaviour of those indicators, using the AMD environments as patterns. As they represent different levels (classes) of contamination, the fuzzy classifier can be used as a tool, allowing a more reasonable approach, compared with classical models, to characterize the environmental impact caused by AMD. In a general way it can be applied to other sites where sulphide-rich waste-dumps are promoting the pollution of superficial water through the generation of AMD

Veliparib in combination with radiotherapy for the treatment of MGMT unmethylated glioblastoma

BackgroundThe O 6 -methylguanine methyltransferase (MGMT) gene is frequently unmethylated in patients with glioblastoma (GBM), rendering them non-responsive to the standard treatment regime of surgery followed by concurrent radiotherapy (RT) and temozolomide. Here, we investigate the efficacy of adding a PARP inhibitor, veliparib, to radiotherapy to treat MGMT unmethylated GBM.MethodsThe inhibition of PARP with veliparib (ABT-888), a potent and orally bioavailable inhibitor in combination with RT was tested on a panel of patient derived cell lines (PDCLs) and patient-derived xenografts (PDX) models generated from GBM patients with MGMT unmethylated tumors.ResultsThe combination of veliparib and RT inhibited colony formation in the majority of PDCLs tested. The PDCL, RN1 showed significantly reduced levels of the homologous repair protein, Mre11 and a heightened response to PARP inhibition measured by increased apoptosis and decreased colony formation. The oral administration of veliparib (12.5 mg/kg, twice daily for 5 days in a 28-day treatment cycle) in combination with whole brain RT (4 Gy) induced apoptosis (Tunel staining) and decreased cell proliferation (Ki67 staining) in a PDX of MGMT unmethylated GBM. Significantly longer survival times of the PDX treated with the combination treatment were recorded compared to RT only or veliparib only.ConclusionsOur results demonstrate preclinical efficacy of targeting PARP at multiple levels and provide a new approach for the treatment of MGMT unmethylated GBM.<br /

Fluid Mechanics in Dentinal Microtubules Provides Mechanistic Insights into the Difference between Hot and Cold Dental Pain

Dental thermal pain is a significant health problem in daily life and dentistry. There is a long-standing question regarding the phenomenon that cold stimulation evokes sharper and more shooting pain sensations than hot stimulation. This phenomenon, however, outlives the well-known hydrodynamic theory used to explain dental thermal pain mechanism. Here, we present a mathematical model based on the hypothesis that hot or cold stimulation-induced different directions of dentinal fluid flow and the corresponding odontoblast movements in dentinal microtubules contribute to different dental pain responses. We coupled a computational fluid dynamics model, describing the fluid mechanics in dentinal microtubules, with a modified Hodgkin-Huxley model, describing the discharge behavior of intradental neuron. The simulated results agreed well with existing experimental measurements. We thence demonstrated theoretically that intradental mechano-sensitive nociceptors are not “equally sensitive” to inward (into the pulp) and outward (away from the pulp) fluid flows, providing mechanistic insights into the difference between hot and cold dental pain. The model developed here could enable better diagnosis in endodontics which requires an understanding of pulpal histology, neurology and physiology, as well as their dynamic response to the thermal stimulation used in dental practices