Heterogeneously Catalyzed Methanolysis of Gmelina Seed Oil to Biodiesel

The heterogeneous catalysis of transesterification of gmelina seed oil to biodiesel is evaluated. The oil was extracted from the seeds with n‐hexane by solvent extraction and characterized to determine its physiochemical properties. Response surface methodology was applied to optimize the effect of process variables on the biodiesel yield. The base‐activated clay catalyst performed as montmorillonite clay with the characteristic property of a Brønsted acid. It has an improved surface area after activation that enhanced its catalytic activity on transesterification reaction. Under optimal conditions, the biodiesel yield was 70.1 %, thus demonstrating that the model predicted well the biodiesel production.     

Cell-envelope proteinases from lactic acid bacteria: Biochemical features and biotechnological applications

Proteins displayed on the cell surface of lactic acid bacteria (LAB) perform diverse and important biochemical roles. Among these, the cell-envelope proteinases (CEPs) are one of the most widely studied and most exploited for biotechnological applications. CEPs are important players in the proteolytic system of LAB, because they are required by LAB to degrade proteins in the growth media into peptides and/or amino acids required for the nitrogen nutrition of LAB. The most important area of application of CEPs is therefore in protein hydrolysis, especially in dairy products. Also, the physical location of CEPs (i.e., being cell-envelope anchored) allows for relatively easy downstream processing (e.g., extraction) of CEPs. This review describes the biochemical features and organization of CEPs and how this fits them for the purpose of protein hydrolysis. It begins with a focus on the genetic organization and expression of CEPs. The catalytic behavior and cleavage specificities of CEPs from various LAB are also discussed. Following this, the extraction and purification of most CEPs reported to date is described. The industrial applications of CEPs in food technology, health promotion, as well as in the growing area of water purification are discussed. Techniques for improving the production and catalytic efficiency of CEPs are also given an important place in this review.     

Computational investigation of hydraulic performance variation with geometry in gabion stepped spillways

Over recent years, there has been a clear increase in the frequency of reported flooding events around the world. Gabion structures offer one means of flood mitigation in dam spillways. These types of structures provide an additional challenge to the computational modeller in that flow through the porous gabions must be simulated. We have used a computational model to investigate the flow over gabion stepped spillways. The model was first validated against published experimental results. Then, gabion stepped spillways with four different step geometries were tested under the same conditions in order to facilitate inter-comparisons and to choose the best option in terms of energy dissipation. The results show that normal gabion steps can dissipate more energy than overlap, inclined, and pooled steps. An intensive set of tests with varying slope, stone size, and porosity were undertaken. The location of the inception point and the water depth at this point obtained from this study were compared with those from existing formulae. Two new empirical equations have been derived, on the basis of a regression analysis, to provide improved results for gabion stepped spillways.     

Digital Extraction Column: Measurement and Modeling Techniques

The digitization of extraction columns requires a profound knowledge of the present hydrodynamics/mass transport interaction as well as appropriate measurement techniques for the detection of relevant input and target values. In this article, the different techniques for droplet size distribution as well as concentration determination are presented and new methods for online evaluation are discussed. In combination with the simulation of droplet size, holdup and solute concentration distribution, an online-capable process tool for controlling and optimizing extraction columns will be obtained.     

Optimisation of cogeneration system and fuel inventory with automated targeting model

Clean Technologies and Environmental Policy - Industrial wastes can be used as alternative fuel sources for the substitution of fossil fuel if they contain good calorific values. Through...     

Spatial distribution of manganese in enamel and coronal dentine of human primary teeth

Emerging evidence indicates that excessive exposure to manganese (Mn) during the prenatal period and early childhood may result in neurodevelopmental deficits. However, accurate exposure biomarkers are not well established, limiting our understanding of exposure-response relationships over these susceptible periods of development. Naturally shed deciduous teeth are potentially a useful biomarker of environmental exposure to Mn. However, the uptake and distribution of Mn in human teeth has not been studied in detail.Mn distribution was measured at high resolution (~ 20 μm) in eight human primary teeth using laser ablation-inductively coupled plasma-mass spectrometry. A bio-imaging methodology was applied to construct detailed elemental maps of three incisors, and bone meal (NIST SRM 1486) was used to validate the analyses.The distribution of Mn in enamel and coronal dentine showed a distinct and reproducible pattern. In enamel, the ⁵⁵Mn:⁴³Ca ratio was highest at the outer edge of enamel (range = 0.57 to 4.74) for approximately 20-40 μm but was substantially lower in deeper layers (range = 0.005 to 0.013). The highest levels of Mn were observed in dentine immediately adjacent the pulpal margin (⁵⁵Mn:⁴³Ca range = 2.27 to 6.95). Importantly, a clearly demarcated high Mn zone was observed in dentine at the incisal end of the teeth. Using confocal laser scanning microscopy to visualize the neonatal line, this region was identified as being in the prenatally formed dentine.The high-resolution map of the spatial distribution of Mn in human primary teeth highlighted specific reproducible patterns of Mn distribution in enamel and coronal dentine.     

Spatial Planning and Policy Integration: Concepts,Facilitators and Inhibitors

While the concept of policy integration is not a new idea within spatial planning discourse, it is becoming increasingly prevalent. Frequently, however, the term is used without any clear definition of what it means, or how it might be achieved. The aim of this paper is to provide more clarity about the concept and to identify the types of actions in the field of planning where integration with policy can be improved. In so doing, the paper assembles a range of material from different disciplines, and identifies some of the key inhibitors and facilitators of policy integration.     

Hydromorphological,hydraulic and ecological effects of restored wood: findings and reflections from an academic partnership approach

Large wood (re)introduction can deliver multiple benefits in river restoration, but there is a dearth of the detailed and longer‐term post‐project monitoring and evaluation required for improving best practice. We present findings from an academic partnership approach to post‐project evaluation, based on successive MSc research projects on restored large wood in the Loddon catchment, UK. Field and modelling data reveal: (i) key differences in large wood features between restored and natural reaches; (ii) increased hydraulic retention and changes to mesohabitats associated with large wood; (iii) differences in macroinvertebrate community composition around large wood but a lack of site‐level effects; (iv) interactions between macrophytes and large wood that may be specific to restored reaches; (v) a need for further field and modelling studies to inform the accurate representation of large wood in hydraulic models. Some key challenges in partnership working are identified to aid planning and effectiveness of future collaborations.     

Measurement of Electrophysiological Signals In Vitro Using High-Performance Organic Electrochemical Transistors

Biological environments use ions in charge transport for information transmission. The properties of mixed electronic and ionic conductivity in organic materials make them ideal candidates to transduce physiological information into electronically processable signals. A device proven to be highly successful in measuring such information is the organic electrochemical transistor (OECT). Previous electrophysiological measurements performed using OECTs show superior signal-to-noise ratios than electrodes at low frequencies. Subsequent development has significantly improved critical performance parameters such as transconductance and response time. Here, interdigitated-electrode OECTs are fabricated on flexible substrates, with one such state-of-the-art device achieving a peak transconductance of 139 mS with a 138 µs response time. The devices are implemented into an array with interconnects suitable for micro-electrocorticographic application and eight architecture variations are compared. The two best-performing arrays are subject to the full electrophysiological spectrum using prerecorded signals. With frequency filtering, kHz-scale frequencies with 10 µV-scale voltages are resolved. This is supported by a novel quantification of the noise, which compares the gate voltage input and drain current output. These results demonstrate that high-performance OECTs can resolve the full electrophysiological spectrum and suggest that superior signal-to-noise ratios could be achieved in high frequency measurements of multiunit activity.