High-Performance Bioinstrumentation for Real-Time Neuroelectrochemical Traumatic Brain Injury Monitoring

Traumatic brain injury (TBI) has been identified as an important cause of death and severe disability in all age groups and particularly in children and young adults. Central to TBIs devastation is a delayed secondary injury that occurs in 30–40% of TBI patients each year, while they are in the hospital Intensive Care Unit (ICU). Secondary injuries reduce survival rate after TBI and usually occur within 7 days post-injury. State-of-art monitoring of secondary brain injuries benefits from the acquisition of high-quality and time-aligned electrical data i.e., ElectroCorticoGraphy (ECoG) recorded by means of strip electrodes placed on the brains surface, and neurochemical data obtained via rapid sampling microdialysis and microfluidics-based biosensors measuring brain tissue levels of glucose, lactate and potassium. This article progresses the field of multi-modal monitoring of the injured human brain by presenting the design and realization of a new, compact, medical-grade amperometry, potentiometry and ECoG recording bioinstrumentation. Our combined TBI instrument enables the high-precision, real-time neuroelectrochemical monitoring of TBI patients, who have undergone craniotomy neurosurgery and are treated sedated in the ICU. Electrical and neurochemical test measurements are presented, confirming the high-performance of the reported TBI bioinstrumentation

Composting paper and grass clippings with anaerobically treated palm oil mill effluent

Purpose The purpose of this study is to investigate the composting performance of anaerobically treated palm oil mill effluent (AnPOME) mixed with paper and grass clippings. Methods Composting was conducted using a laboratory scale system for 40 days. Several parameters were determined: temperature, mass reduction, pH, electrical conductivity, colour, zeta potential, phytotoxicity and final compost nutrients. Results The moisture content and compost mass were reduced by 24 and 18 %, respectively. Both final compost pH value and electrical conductivity were found to increase in value. Colour (measured as PtCo) was not suitable as a maturity indicator. The negative zeta potential values decreased from −12.25 to −21.80 mV. The phytotoxicity of the compost mixture was found to decrease in value during the process and the final nutrient value of the compost indicates its suitability as a soil conditioner. Conclusions From this study, we conclude that the addition of paper and grass clippings can be a potential substrate to be composted with anaerobically treated palm oil mill effluent (AnPOME). The final compost produced is suitable for soil conditioner

A Sequential Mixed Method Study of Employee Job Satisfaction in Upscale Restaurants, Malaysia

The study determines the main factors affecting job satisfaction in upscale restaurants and their degree of comparative influence. The research initially involves qualitative data analysis of 20 interviews with restaurant employees representing five upscale restaurants in Kuala Lumpur (KL), followed by structural equation modeling of data retrieved from 368 questionnaires from 16 KL restaurants. The impact variance of four main determinants of job satisfaction are revealed, where the “working environment” has the highest impact, followed by “payment and compensation,” “promotion”, and finally, “workplace fairness”. Crucially, “workplace relationships” have a moderating effect on the relationship between the “work environment” and job satisfaction, implicating industry-applied recommendations to strengthen job satisfaction levels

Measurement of Shear Modulus Profile Using a Continuous Surface Wave Measurement System

For most ground response analyses, the shear modulus is an important parameter to be determined and it has to be measured over a large strain range, so as to characterise the soil behavior under various loading conditions. Laboratory measurement of shear modulus covers a limited strain range depending on the test method. The main difficulty lies in the determination of the shear modulus at very small strains. In this respect, geophysical methods are more attractive. One of these test methods, which uses a continuous surface wave, is used to obtain the shear modulus profile at two sites in Singapore. The Continuous Surface Wave System (CSWS) is a nonintrusive field geophysical test consisting of a vibrator source and several receiver geophones connected to a computer system. The computer collects and analyses the field data, and provides a shear modulus profile at the test site. Conclusions from the field tests support published literature that such field seismic tests are capable of measuring the low-strain shear modulus well. The interpretation of field test data in the absence of specific stratigraphic information can pose some difficulties. An important part in interpreting continuous surface wave measurement data is in the selection of a suitable inversion tool so as to derive the correct shear modulus profile for the site under consideration. A finite element approach (using LS DYNA) is investigated for inversion of field test data. Data obtained from S-wave cross-hole survey are also compared with field tests data obtained using CSWS

Removal and transformation of hexavalent chromium in sequencing batch reactor

The objectives of this study are to evaluate the efficiency of removal of hexavalent chromium (Cr(VI)) in a sequencing batch reactor (SBR) and to ascertain the fate of Cr(VI) in the treatment process. An SBR was operated with the FILL, REACT, SETTLE, DRAW and IDLE periods in the time ratio of 2:12:2:1.5:6.5 for a cycle time of 24 h. The study was divided into 5 phases with the addition of 0.5, 2.0, 3.0 and 5.0 mg/ℓ of Cr(VI) in Phases II, III, IV and V for a duration of 46, 75, 43 and 16 operational cycles, respectively. The Cr(VI) removal efficiencies for SBR were found to be 79.8, 88.4 and 99.8% in Phases III, IV and V, respectively. The results revealed that Cr(VI) removal efficiency improved with acclimated activated sludge. Determination of Cr in the suspended sludge showed that around 95% of the Cr species were Cr(III). Determination of Cr concentration profiles during the FILL and REACT periods showed that the predominant species was Cr(III) as Cr(VI) was bio-reduced. The proposed Cr(VI) removal mechanism involves bioreduction to Cr(III) which was subsequently precipitated and adsorbed by activated sludge. Precipitation rather than sorption is envisaged to be the main path of removal of Cr(III) from the solution.Keywords: Sequencing batch reactor, hexavalent chromium, removal, transformation, mechanis

The effect of Bi promoter on vanadium phosphate catalysts synthesized via sesquihydrate route

A series of 1%, 3% and 5% Bi-doped vanadyl pyrophosphate catalysts were prepared via sesquihydrate route (VPOs method). These catalysts were denoted as VPOs-Bi1%, VPOs-Bi3% and VPOs-Bi5%. Bulk and Bi-promoted vanadyl pyrophosphate catalysts prepared via sesquihydrate route exhibited a well-crystallized (VO)2P2O7 phase. Two V5+ phases, i.e. β-VOPO4 and αII-VOPO4 were observed in all Bi-promoted VPO catalysts, which led to an increase in the specific surface area and average oxidation state of vanadium. Bi-promoted VPO catalysts showed six to nine times higher amounts of oxygen evolved than the bulk VPO catalyst in oxygen TPD and a significant shift in the reduction peaks to lower temperatures. Catalytic tests revealed that both activity and selectivity to maleic anhydride increased with the presence of bismuth promoter

Development of coconut oil/capric acid eutectic phase change material with graphene as latent thermal energy storage.

In this study, a eutectic mixture of coconut oil (CO)-capric acid (CA) was synthesised and investigated with the aim of producing newly eutectic phase change materials (PCMs) with improved thermal properties as thermal energy storage (TES). Although eutectic fatty acids have been widely studied, the information on the thermal properties of the CO-CA eutectic mixture is very limited to the authors' knowledge. Coconut oil offers good thermal and chemical stability with acceptable latent heat and melting temperature. The thermal properties of the eutectic mixture were enhanced by graphene addition at 1, 3, 5, and 7 wt% concentrations. The surfactant was added to the mixture to avoid the sedimentation of graphene. The material characterisation techniques include thermal conductivity measurement, Fourier Transform Infrared (FTIR) spectroscopy, Differential Scanning Calorimetry (DSC), and Thermal Gravimetric (TG) analysis. The results revealed that the pure eutectic CO-CA has a melting point of 23.5°C with a latent heat of 110 J/g. With the addition of graphene, the melting point of the mixture is 22.8°C, and the latent heat is 103 J/g. Overall, the findings showed that the thermal conductivity improved by 21.7% for 7wt% graphene concentration. The spectra from FTIR and TG analysis showed that the mixture offers thermal and chemical stability. The promising findings in this study showed that the newly developed eutectic mixture with improved thermal properties makes them favourable to be used as TES for low-temperature applications

Ni(OH)2 decorated rutile TiO2 for efficient removal of tetracycline from wastewater

Flower-like and coral-like particles composed of rutile TiO2 nanorods were synthesized via hydrolysis of TiCl4 in water at room temperature and hydrothermal crystallization. The subsequent deposition of Ni(OH)2 clusters resulted in enhanced adsorption property and photocatalytic activity. In particular, Ni(OH)2-modified coral-like rutile TiO2 was shown to efficiently remove 76% of tetracycline from 100 mg L−1 solution after 30 min adsorption and subsequent 2 h photodegradation under visible light; whereas only 57% tetracycline removal was achieved by the commercial TiO2 (P25). In addition, the micro-sized Ni(OH)2-modified rutile TiO2 particles could be easily recovered from water after the photocatalytic process, and showed significant advantages over nano-sized photocatalysts. Our study provides a simple and green route to synthesizing photocatalysts with enhanced adsorption and photocatalytic performance for potential applications in practical water purification and wastewater treatment

An improved wrapper-based feature selection method for machinery fault diagnosis

A major issue of machinery fault diagnosis using vibration signals is that it is over-reliant on personnel knowledge and experience in interpreting the signal. Thus, machine learning has been adapted for machinery fault diagnosis. The quantity and quality of the input features, however, influence the fault classification performance. Feature selection plays a vital role in selecting the most representative feature subset for the machine learning algorithm. In contrast, the trade-off relationship between capability when selecting the best feature subset and computational effort is inevitable in the wrapper-based feature selection (WFS) method. This paper proposes an improved WFS technique before integration with a support vector machine (SVM) model classifier as a complete fault diagnosis system for a rolling element bearing case study. The bearing vibration dataset made available by the Case Western Reserve University Bearing Data Centre was executed using the proposed WFS and its performance has been analysed and discussed. The results reveal that the proposed WFS secures the best feature subset with a lower computational effort by eliminating the redundancy of re-evaluation. The proposed WFS has therefore been found to be capable and efficient to carry out feature selection tasks