Biotechnology for environmently-friendly leather production

Content: The leather industry has been challenged to reduce its environmental impact, for example, by producing eco-friendly products with inherent biodegradability using less polluting chemicals. Conventional depilation of hair and wool consumes a large amount of lime and sodium sulphide, which poses a serious waste disposal concern. Volatile organosulphur compounds remaining in leather products may provoke an unpleasant odour and be the cause of a deterioration in indoor air quality. Traditional leather production also generates tanned waste which cannot be readily degraded by microorganisms. LASRA research is guiding the application of biotechnology to help the New Zealand leather industry develop environmentally sustainable leather processes, replacing hazardous chemicals with microbial enzymes. Using 16S rRNA gene sequencing, we have isolated and identified a number of indigenous bacteria from the leather industry environment which are being adopted to develop benign leather processing technologies. We discovered a strain of Stenotrophomonas spp. with significant and beneficial proteolytic activity in a tannery sludge. The identified strain not only displays collagenase activity but also the ability to reduce hexavalent chromium to trivalent chromium, making it an ideal candidate for biodegradation of tanned waste. We also isolated and identified several Bacillus spp. strains from a biofilter used in a leather manufacturing plant which exhibited sulphide oxidation activity, which are being applied in bioremediation of volatile organosulphur compounds emitted by leather products. Recently we revisited the natural autolytic processes of degradation of untreated pelts to guide a natural depilation method without any need for additional chemical treatment. The characterisation of the bacteria isolated from the skins showed the alkaline protease production activity responsible for the observed nature unhairing. We found that in controlled experiments the wool could be removed completely from follicles after 2 days, without obvious damage and leathers could be processed with organoleptic and mechanical properties comparable to conventionally processed counterparts. With the mechanisms revealed, the natural depilation can be controlled to become more reliable and reproducible across a range of conditions. Our current work is focused on the development of solid-state fermentation using skin and leather waste as a culture medium to produce the required enzymes to make biological leather production practical and reproducible. Our research is aimed at enabling the NZ leather industry to produce highquality leather products with a much-reduced environmental footprint. Take-Away: 1. Indigenous bacteria have been isolated and identified from the leather industry environment by the application of 16S rRNA gene sequencing. 2. Biodegradation of tanned waste and bioremediation of volatile organosulphur compounds are being developed. 3. The mechanism of natural depilation has been revealed and the application of enzymatic depilation can become practicable by using solid-state fermentation

Short Term Wave Energy Variability off the West Coast of Ireland

Within the context of wave energy conversion, this paper investigates the practice of using wave (frequency) spectra to characterise wind waves. In particular, this paper looks at the major shortfall of the wave spectrum - its lack of information provision on the temporal variability of the wave activity. Finally, the issue of different spectral shapes with the same seaway summary statistics (i.e. Hs, the significant wave height, and Tz, the mean zero crossing wave period) is investigated. Measured wave data recorded off theWest Coast of Ireland provides the basis for this analysis, with the wavelet transform providing the primary analysis tool

Pengembangan UMKM sebagai Penguatan Ekonomi Kerakyatan di Kota Bukittinggi (Studi Kasus: Industri Kerupuk Sanjai)

This study aims the problems faced by home industry kerupuk Sanjai in the City of Bukittinggi to improve local economy. This study was conducted in March 2015 through a survey method (observation) with random purposive sampling technique. The sample in this study as many as twenty-six home industry Kerupuk Sanjai in Bukittinggi. This research found home industry Kerupuk Sanjai in Bukittinggi city is still traditional both in the production process, packaging and marketing system. So that the necessary cooperation with the relevant agencies in order to create innovation and creativity to improve quality and productivity as well as a broader marketing reach

A Modular Regularized Variational Multiscale Proper Orthogonal Decomposition for Incompressible Flows

In this paper, we propose, analyze and test a post-processing implementation of a projection-based variational multiscale (VMS) method with proper orthogonal decomposition (POD) for the incompressible Navier-Stokes equations. The projection-based VMS stabilization is added as a separate post-processing step to the standard POD approximation, and since the stabilization step is completely decoupled, the method can easily be incorporated into existing codes, and stabilization parameters can be tuned independent from the time evolution step. We present a theoretical analysis of the method, and give results for several numerical tests on benchmark problems which both illustrate the theory and show the proposed method's effectiveness

Multi-core strategies for particle methods

This paper discusses the implementation of particle based numerical methods on multi-core machines. In contrast to cluster computing, where memory is distributed across machines, multi-core machine can share memory across all cores. Here general strategies are developed for spatial management of particles and sub-domains that optimize computation on shared memory machines. In particular, we extend cell hashing so that cells bundle particles into orthogonal tasks that can be safely distributed across cores avoiding the use of "memory locks" while still protecting against race conditions. Adjusting task size provides for optimal load balancing and maximizing cache hits. Additionally, the way in which tasks are mapped to execution threads has a significant influence on the memory footprint and it is shown that minimizing memory usage is one of the most important factors in achieving execution speed and performance on multi-core. A novel algorithm called H-Dispatch is used to pipeline tasks to processing cores. The performance is demonstrated in speed-up and efficiency tests on a smooth particle hydrodynamics (SPH) flow simulator. An efficiency of over 90% is achieved on a 24-core machine

A Multi-Core Numerical Framework for Characterizing Flow in Oil Reservoirs

Presented at the SCS Spring Simulation Multi-Conference – SpringSim 2011, April 4-7, 2011 – Boston, USA Awarded Best Paper in the 19th High Performance Computing Symposium and Best Overall Paper at SpringSim 2011.This paper presents a numerical framework that enables scalable, parallel execution of engineering simulations on multi-core, shared memory architectures. Distribution of the simulations is done by selective hash-tabling of the model domain which spatially decomposes it into a number of orthogonal computational tasks. These tasks, the size of which is critical to optimal cache blocking and consequently performance, are then distributed for execution to multiple threads using the previously presented task management algorithm, H-Dispatch. Two numerical methods, smoothed particle hydrodynamics (SPH) and the lattice Boltzmann method (LBM), are discussed in the present work, although the framework is general enough to be used with any explicit time integration scheme. The implementation of both SPH and the LBM within the parallel framework is outlined, and the performance of each is presented in terms of speed-up and efficiency. On the 24-core server used in this research, near linear scalability was achieved for both numerical methods with utilization efficiencies up to 95%. To close, the framework is employed to simulate fluid flow in a porous rock specimen, which is of broad geophysical significance, particularly in enhanced oil recovery

Glyoxal Formation and Its Role in Endogenous Oxalate Synthesis

Calcium oxalate kidney stones are a common condition affecting many people in the United States. The concentration of oxalate in urine is a major risk factor for stone formation. There is evidence that glyoxal metabolism may be an important contributor to urinary oxalate excretion. Endogenous sources of glyoxal include the catabolism of carbohydrates, proteins, and fats. Here, we review all the known sources of glyoxal as well as its relationship to oxalate synthesis and crystal formation