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A polymer electrolyte fuel cell (PEFC) is an electrochemical device that converts chemical energy into electrical energy and heat. The energy conversion is simple; however, the multiphysics phenomena involved in the energy conversion process must be analyzed in detail. The gas diffusion layer (GDL) provides a diffusion media for reactant gases and gives mechanical support to the fuel cell. It is a

Many Gram-positive pathogenic bacteria employ ribosomal protection proteins (RPPs) to confer resistance to clinically important antibiotics. In Bacillus subtilis, the RPP VmlR confers resistance to lincomycin (Lnc) and the streptogramin A (SA) antibiotic virginiamycin M (VgM). VmlR is an ATP-binding cassette (ABC) protein of the F type, which, like other antibiotic resistance (ARE) ABCF proteins,

The stringent response is a global reprogramming of bacterial physiology that renders cells more tolerant to antibiotics and induces virulence gene expression in pathogens in response to stress. This process is driven by accumulation of the intracellular alarmone guanosine-5′-di(tri)phosphate-3′-diphosphate ((p)ppGpp), which is produced by enzymes of the RelA SpoT homologue (RSH) family. The Gram-

Energy dispersive x-ray spectroscopy in a transmission electron microscope is often the first method employed to characterize the composition of nanowires. Ideally, it should be accurate and sensitive down to fractions of an atomic percent, and quantification results are often reported as such. However, one can often get substantial errors in accuracy even though the precision is high: for nanowir

Photonic materials for high-temperature applications need to withstand temperatures usually higher than 1000 °C, whilst keeping their function. When exposed to high temperatures, such nanostructured materials are prone to detrimental morphological changes, however the structure evolution pathway of photonic materials and its correlation with the loss of material's function is not yet fully underst

Body acceleration due to heartbeat-induced reaction forces can be measured as mobile phone accelerometer (m-ACC) signals. Our aim was to test the feasibility of using m-ACC to detect changes induced by stress by ultra-short heart rate variability (USV) indices (standard deviation of normal-to-normal interval-SDNN and root mean square of successive differences-RMSSD). Sixteen healthy volunteers wer

In the present study, strategies are developed to enable time-efficient models for structures subjected to blast loading, appropriate for use in a structural design process. Dynamic sub structuring is employed to obtain reduced models with localized nonlinearities, such as predefined plastic hinges in a beam column structure. The parts of the substructures that remains linear elastic are modeled b

Background: To establish integrated healthcare pathways for patients with neurodevelopmental disorders (ND) such as autism spectrum disorder and attention-deficit hyperactivity disorder is challenging. This study sets out to investigate the main concerns for healthcare professionals when integrating ND care pathways and how they resolve these concerns. Methods: Using classic grounded theory (Glase

Density dependent growth and optical properties of periodic arrays of GaAs nanowires (NWs) by fast selective area growth MOVPE are investigated. As the period of the arrays is decreased from 500 nm down to 100 nm, a volume growth enhancement by a factor of up to four compared with the growth of a planar layer is observed. This increase is explained as resulting from increased collection of precurs

Glutathione (GSH) reduction of the anticancer-active platinum(IV) compounds trans-[PtCl4(NH3)(thiazole)] (1), trans-[PtCl4(cha)(NH3)] (2), cis-[PtCl4(cha)(NH3)] (3) (cha=cyclohexylamine), and cis-[PtCl4(NH3)2] (4) has been investigated at 25 °C in a 1.0 M aqueous medium at pH 2.0–5.0 (1) and 4.5–6.8 (2–4) using stopped-flow spectrophotometry. The redox reactions follow the second-order rate law d[

Reduction of the model platinum(IV) complexes cis-[PtCl4(NH3)(2)] (1), trans-[PtCl4(NH3)(2)] (2). trans-[PtCl2(en)(2)](2+) (3), trans-[PtBr2(NH3)(4)](2+) (4), [PtCl6](2-) (5), and [PtBr6](2-) (6) with L-ascorbic acid (H(2)Asc) in 1.0 M aqueous medium at 25 degreesC in the region 1.75 less than or equal to pH less than or equal to 7.20 has been investigated using stopped-flow spectrophotometry. The

During the last decade, a rapid progress has been made in the development of validated analytical models for the thermal and mechanica1 behaviour of fire exposed structures and structural members. In a long-term perspective, the development now goes towards an analytical design, directly based on a natural fire exposure and specified with respect to the combustion characteristics of the fire load

Popular Abstract in Swedish De flesta produkter som vi dagligen använder tillverkas genom att utnyttja fossila råvaror som olja, kol och naturgas. Ett stort problem är att dessa råvaror bara finns i begränsade mängder i naturen, vilket medför att de förr eller senare tar slut. Dessutom medför förbränning av fossila råvaror att det bildas miljöskadande gaser (t.ex. koldioxid) som ansamlas i atmosfäOne of the major challenges facing the world today is the reduction of our dependency on fossil resources as their exploitation has severe negative effects on the environment. One way of realizing this is to utilise the components of lignocellulosic biomass to a greater extent as feedstock for various industrial products. However, such utilisation requires the extraction of the biopolymers from th

Accident prediction models are often used to predict the number of accidents on segments and at intersections in the road network. Most often the models are developed for a total number of crashes for the facility, or crashes by severity. However, the frequency and severity of crashes of different types can be expected to vary with regards to the underlying phenomena that cause them to occur. To b