MHSP in reversed-biased operation mode for ion blocking in gas-avalanche multipliers

We present recent results on the operation of gas-avalanche detectors comprising a cascade of gas electron multipliers (GEMs) and Micro-Hole and Strip Plates (MHSPs) multiplier operated in reversed-bias (R-MHSP) mode. The operation mechanism of the R-MHSP is explained and its potential contribution to ion-backflow (IBF) reduction is demonstrated. IBF values of 4E-3 were obtained in cascaded R-MHSP and GEM multipliers at gains of about 1E+4, though at the expense of reduced effective gain in the first R- MHSP multiplier in the cascade.Comment: 23 pages, 8 figure

Life cycle cost assessment of insect based feed production in West Africa

While there is a growing body of research investigating the technical feasibility and nutritional properties of insect based feeds (IBFs), thus far little attention has been devoted to gauge the economic implications of implementation. This study has investigated the economic performance of ex-ante modelled IBF production systems operating in the geographical context of West Africa. A Life Cycle Cost (LCC) analysis of recently published life cycle inventory (LCI) data served as a basis to analyse and compare the economic performances of IBF production systems using Musca domestica and Hermetia illucens reared on different substrates. To gauge the application potential of IBF in West Africa, estimated breakeven sale prices of IBFs were benchmarked against the customary market prices of conventional feeds. The results show that the economic performance of IBF production in West Africa is largely determined by the costs attributed to labour and the procurement of rearing substrates, attesting economic advantages to the production of M. domestica larvae by measure of breakeven price (1.28–1.74 EUR/kg IBF) and LCC (1.72–1.99 EUR/kg IBF). A comparison of the breakeven sale prices of IBF with market prices of conventional feeds suggest that IBF has potential to substitute imported fishmeal, but findings offer no support for conjectured economic advantages over plant based feeds

Effect of hot boning on colour stability and antioxidant enzyme activities in beef inner and outer biceps femoris

Meat from double-muscled Belgian Blue cattle is characterized by a fast pH decline and slow temperature fall post mortem (pm), which may provoke heat shortening (pH35°C) and negatively affect meat quality, particularly in deeper muscles of the hindquarter. The aim of this study was to investigate the effect of hot boning (within 2 hours pm) on colour and colour stability and on antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px)) in inner and outer Biceps femoris (IBF and OBF) from 7 Belgian Blue young bulls (mean age and carcass weight 22.7 months and 496 kg respectively). The mean duration of heat shortening was 3.4 hours for the cold-boned IBF, whereas there was no period of heat shortening in the hot-boned IBF and in the cold- and hot-boned OBF. The colour L*-value was higher in the cold-boned IBF than OBF (49.3 and 37.6 respectively; P<0.05) resulting in two-toning, whereas there was no significant difference between hot-boned IBF and OBF (33.8 and 34.3 respectively). Concomitantly, the decrease in a*-value and increase in %metmyoglobin over a 7 day display period was higher (P<0.05) for the cold-boned IBF compared to the hot-boned IBF and the cold- and hot-boned OBF. The activities of CAT, GSH-Px and SOD for the IBF and OBF were not significantly different between hot- and cold-boned samples. Hot boning of Biceps femoris in beef carcasses has distinct advantages over cold boning, especially for avoiding heat shortening in the inner part of the muscle and for increasing the colour uniformity in the muscle

Ibuprofen Nanoparticles and its cytotoxicity on A549 and HaCaT cell lines

yesIbuprofen (IBF) is an outstanding non-steroidal drug for analgesic and anti-inflammatory therapies but it exhibits poor solubility in water [1, 2]. Increased dosage administration has been linked to gastrointestinal and cardiovascular complications [3]. Many techniques have been employed to improve the solubility of NSAIDs [4]. In this study, the anti-solvent precipitation method was used to make Ibuprofen nanoparticles (IBF NPs). Optimised preparation parameters such as solvent (ethanol), raw drug concentration (400 mg), solvent/anti-solvent ratio (1:50) and surfactant concentration (0.25 mg/ml) have been studied to yield nanoparticles with a mean size of 58.8 nm, which is confirmed by dynamic light scattering and transmission electron microscopy. These IBF NPs posess increased aqueous solubility compared to the micro counterpart and maintain with chemical integrity indicated by high performance liquid chromatography and Fourier transform infrared spectroscopy. In addition, in vitro cytotoxicity of IBF NPs has been studied on A549 and HaCat cell lines using MTT and LDH assays. Both cells were obtained from ATCC. The A549 cells were grown in a modification of Ham’s F-12, containing L-glutamine, called F-12K. The HaCaT cells were grown in DMEM containing sodium pyruvate (110 mg/l). Normal cell culture and sub-culture were applied and the cells were used after around 45 passages [5]. The cell culture media containing 105cells/ml were placed in a 96-well plate with addition of IBF NPs and Micro form at concentrations in the range of between 6 and 500 ug/ml by diluting them with DMEM and F-12K for use with the HaCaT and A549 cells respectively. After 24, 48 and 72h exposure, the MTT and LDH cytotoxicity assay were performed in triplicates and on three separate experiment cultures and the absorbance was recorded at 570 nm and 492nm respectively with Elisa micro plate reader. The cell viability (%) related to control (cells in culture medium without NPs) was calculated. A very good cytotoxicity profile was observed, indicating an in vitro cytocompatibility of the IBF NPs in these cell culture systems and no significant changes in cytotoxicity compared with Micro IBF. We conclude that our IBF NPs have increased solubility, same chemical integrity and unchanged cytotoxicity compared to IBF Micro drug. Further work will concentrate on optimising more rigorous parameter to produce excellent quality NPs. More detailed characterisation of IBF NPs is to be tested, such as using PXRD and SEM to further corroborate particle shape and size. The range of no toxic in vitro concentrations is also to be further confirmed. Eventually scaled up preparation of IBF NPs will be developed without relinquishing NPs quality. This would improve the potential for in vitro/ in vivo applications and clinical use of IBF NPs and NSAIDs in general

Sustainable Water Treatment with Induced Bank Filtration

This study demonstrates that an induced bank filter (IBF) system can treat raw water polluted with Escherichia coli (E. coli) bacteria. Similar to riverbank filtration (RBF), induced or reversed bank filtration relies on natural processes to clean water, including filtration through layers of allochthone alluvial sediments and a bioactive layer that forms on top of the filter after a ripening period. At the study site, located in Southwestern India, villagers rely on a mountain spring for their water supply. Although of generally high quality, the spring water contains E. coli bacteria (up to ~2000 MPN/100 mL). Raw water diverted from this spring was gravity-fed into the IBF system, which consisted of a (1) flow regulator, (2) pre-filter and (3) the actual IBF filter. Designed and constructed based on pilot testing of prototype filters, a full-scale filter (5 m by 7 m by 2 m) was built and its performance and maintenance requirements were studied during both the monsoon season and the dry season. The data show that the IBF significantly improved the water quality. Turbidity and E. coli concentrations were reduced to or below the detection limit (approximately 2.5 log unit reduction). During the peak of the monsoon season (August), E. coli was present in the IBF effluent after a storm destroyed the cover of the IBF tank. The IBF construction and maintenance costs were documented. Extrapolated over a 10-year period, the cost of IBF water was 3 and 10 times lower than reverse osmosis or water supplied by truck, respectively. This study demonstrates that IBF can be part of an affordable water supply system for rural villages in mountainous terrain where conventional RBF systems cannot be installed or where other water treatment technologies are out of financial reach

The intrinsic bayes factor described by an example

The Intrinsic Bayes Factor (IBF) has been recently introduced by Berger and Pericchi (1996) for automatic model selection and hypothesis testing in a Bayesian framework. A major result is the existence, in hypothesis testing problems, of an Intrinsic Proper Prior (JPP) that can be obtained from the IBF in an automatic way. In this article we describe the IBF and compute the IPP in a simple example. It is the hope that the present article will help in making Bayesian methods more widely used for Testing Hypothesis

Performance of a large aperture GEM-like gating device for the International Linear Collider

One of the potential problems of a Micro-Pattern Gaseous Detector (MPGD)-based Time Projection Chamber (TPC) is the Ion back Flow (IBF): ions generated through the avalanche amplification process flow back to the drift volume of the TPC and disarrange an electric field inside it. Consequently non-negligible degradation of azimuthal spatial resolution is caused due to this IBF. Meanwhile, it is necessary to collect primary ionized electrons to maintain intrinsic performance of the MPGDs. The MPGD based TPC is currently planned to be used as a central tracking detector of the International Large Detector (ILD), which is one of the detector concepts for the future International Linear Collider (ILC) project, and which requires fine azimuthal spatial resolution of less than 100 ${\rm \mu m}$ over the drift length of the TPC to attain high momentum resolution. Because of a unique beam structure of the ILC, the IBF is a critical issue for the realization of the ILD-TPC. Not only to suppress the ion back-flow to the drift volume, but also to allow the primary electrons pass through, a large aperture GEM-like gating device has been developed. Several bench tests for confirming the performance of the gating device have been conducted, besides that, beam test with the full detector module equipped with the gating device was carried out to verify the resolution that the full module can provide. As a result, it turned out that the developed gating device fulfills requirements for maintaining the performance of the MPGD based TPC, and it has sufficient performance for the central tracker of the ILD at the ILC.Comment: 2017 IEEE Nuclear Science Symposium Conference Recor