Simplified construction and performance of a device for particle bombardment

A modified particle inflow gun (PIG), that utilized a plastic vacuum chamber, was compared with a conventional PIG by bombarding cantaloupe (Cucumis melo L.) cotyledon basal quarters with plasmid pBI221 (Clontech Inc.) containing a -glucuronidase (GUS) gene adsorbed onto tungsten particles. Both guns produced an equivalent number of transient GUS foci when tested at 410 kPa (60 psi), 620 kPa (90 psi) or 830 kPa (120 psi) helium and at a 10, 15 or 20 cm gap between the specimen and DNA/particle holder screen. For both guns, treatments utilizing the lower pressure and/or the greater distance generally produced significantly fewer GUS-positive foci. The plastic PIG was convenient to operate and could be built with simple hand tools in less than 40 minutes, using readily available parts.     

A PCA-based method for construction of composite sustainability indicators

Purpose

Sustainable manufacturing is practiced globally as a comprehensive strategy for improving the sustainability performance of the manufacturing industry. While sustainability is characterized into such three dimensions as economic, environmental, and social, currently, there is no quantitative method yet to measure the so-called ??sustainability?? in the manufacturing industry. The objective of this research is to develop a comprehensive and effective quantitative method to measure the overall sustainability performance of manufacturing companies.

Methods

In this paper, an integrated methodology is presented for the development of composite sustainability indicators based on principal component analysis (PCA). In developing this integrated approach, both industry and academia surveys are conducted to identify what sustainability indicators are favored by the sustainable manufacturing community. A unique index is then generated to measure the overall sustainability performance of industrial practices. The methodology can be used for benchmarking the overall sustainability performance of various manufacturing companies.

Results

A case study is conducted on a total of 11 global electronic manufacturing companies. The overall sustainability performance of these companies are measured, benchmarked, and ranked. The results showed that PCA is an effective approach for constructing composite sustainability indicators across environmental, economic, and social dimensions.

Conclusions

From this research, it is found that industry and academia have different views on the sustainability measurement, evidenced by different weights put on the same indicator in industry and academia. The case study demonstrated that the methodology presented in this paper is an effective tool for comprehensive measurement of sustainability performance of manufacturing companies. Strengths and weaknesses of each company can be identified. Then, the recommended improvements can be suggested based on the study of each of the individual indicators.     

Physical characteristics of bone composite materials

To study the effects of varying mineral content and various trace elements in bone composities on its electrical behavior and possible use in design of transducers, various physical, dielectric, piezoelectric, and electromechanical parameters have been measured. For electrical characterization of various such composites in the high-frequency region (1–108 MHz), variation of impedance (Z), phase angle (tan ), and relative output voltage with frequency has been examined. Furtherfore, the Curie temperature has been determined and the temperature variation of capacitance and loss factor (tan ) studied (24–225°C). Two types of bone composites were prepared and studied. First, powdered collagen and apatite obtained from full bone were mixed intimately in various proportions by weight to prepare eleven bone compositions. Second, such bone materials were made to contain 5–10% various doping foreign additives (A1Br₃, Na₂CO₃, SrCO₃, LiCO₃, Sb₂O₃, ZnO, Nb₂O₅, piezoelectric ceramic (PZT), and Pb(NO₃)₂. It has been observed that a bone composition of 50% collagen + 50% apatite has possible piezoelectric application and other compositions [85% collagen + 15% apatite, 90% collagen + 10% ZnO, and 90% bone + 10% Ba(OH)₂] have a sharp rise in capacitance near the Curie temperature. The Curie temperature is generally shifted towards higher values by additives. It is expected that such results will be relevant in characterizing bone behavior.     

Microbial growth on fiber reinforced composite materials

Microorganisms may be responsible for physical and chemical changes in composite materials. Inoculation of a fungal consortium to pre-sterilized coupons of five composites resulted in deep penetration into the interior of all materials at a temperature of approximately 22°C within 5 weeks. Scanning electron microscopy (SEM) showed that the inoculated composites were etched by the microorganisms. None of the five composites tested resisted fungal attack. Inoculation of extracts of these composites with the same fungi resulted in higher growth compared to the control, suggesting that chemical compounds leached from the composites were utilized by microorganisms as a source of carbon and energy. Studies with pure fibers used in the manufacture of composite materials showed that the fungi grew rapidly on both glass and carbon fibers in the presence of the fungal consortium. Our study indicates that microorganisms pose a threat to composite materials. We are currently investigating chemical and physical changes induced in these materials by the growth of fungi.     

Kinetic structures in multi-phase liquid-crystalline composite materials

A mesoscopic kinetic model for phase separation in the presence of liquid crystalline order has been formulated and solved using high performance numerical methods. The thermodynamic phase diagram on temperature–polymer concentration plane indicates the presence of coexistence regions between isotropic and liquid crystalline phases. These regions are partitioned by the phase-separation spinodal and the phase-ordering spinodal. We characterize the morphologies following temperature quenches in the phase diagram. The scenario is completely different from isotropic mixing since the continuous phase exhibits liquid crystalline ordering. Microdomains of the dispersed phase induce long- and short-range forces affecting the kinetics of the phase separation and the emerging structures. Presence of topological defects and elastic distortions around the microdomains formed during the phase separation dominate the morphology. The free energy of the system establishes dynamics and correlations of the morphological structures.     

Environmental impacts of wooden,plastic, and wood-polymer composite pallet: a life cycle assessment approach

Purpose

Waste recycling is one of the essential tools for the European Union’s transition towards a circular economy. One of the possibilities for recycling wood and plastic waste is to utilise it to produce composite product. This study analyses the environmental impacts of producing composite pallets made of wood and plastic waste from construction and demolition activities in Finland. It also compares these impacts with conventional wooden and plastic pallets made of virgin materials.

Methods

Two different life cycle assessment methods were used: attributional life cycle assessment and consequential life cycle assessment. In both of the life cycle assessment studies, 1000 trips were considered as the functional unit. Furthermore, end-of-life allocation formula such as 0:100 with a credit system had been used in this study. This study also used sensitivity analysis and normalisation calculation to determine the best performing pallet.

Result and discussion

In the attributional cradle-to-grave life cycle assessment, wood-polymer composite pallets had the lowest environmental impact in abiotic depletion potential (fossil), acidification potential, eutrophication potential, global warming potential (including biogenic carbon), global warming potential (including biogenic carbon) with indirect land-use change, and ozone depletion potential. In contrast, wooden pallets showed the lowest impact on global warming potential (excluding biogenic carbon). In the consequential life cycle assessment, wood-polymer composite pallets showed the best environmental impact in all impact categories. In both attributional and consequential life cycle assessments, plastic pallet had the maximum impact. The sensitivity analysis and normalisation calculation showed that wood-polymer composite pallets can be a better choice over plastic and wooden pallet.

Conclusions

The overall results of the pallets depends on the methodological approach of the LCA. However, it can be concluded that the wood-polymer composite pallet can be a better choice over the plastic pallet and, in most cases, over the wooden pallet. This study will be of use to the pallet industry and relevant stakeholders.

     

Representation of sound pressure and particle motion information in the midbrain of the goldfish

1. Averaged evoked responses from multiple electrodes in the goldfish midbrain (torus semicircularis) area were recorded in response to acoustic stimulation by loudspeaker and to direct vertical vibration of the head. 2. Relative pressure and displacement sensitivity was such that in the far field, the response to sound pressure would dominate the response to particle motion by 40-90 dB. 3. Swimbladder deflation caused a flat (70-1000 Hz) loss in pressure sensitivity ranging from 20 to over 50 dB, and led to an enhanced response to vibration at low frequencies. 4. The goldfish midbrain is not homogeneous with regard to relative pressure and motion sensitivity.     

RNA-binding domain of the key structural protein P7 for the Rice dwarf virus particle assembly

The Rice dwarf virus (RDV) P7 structural protein is the key protein in the RDV particle assembly. The P7 protein was digested partially or completely by Staphylococcus aureus V8 protease and/or Pseudomonasfragi Asp-N protease. The molecular mass and the N-terminal amino acid sequence of the polypeptide fragments of the P7 protein were determined by SDS-PAGE and the Edman degradation method, respectively. Then the polypeptides were located in the deduced amino acid sequence of the RDV P7 protein based on the nucleotide sequence information, with the knowledge of the specific cleavage sites of the Staphylococcus aureus V8 and Pseudomonasfragi Asp-N protease, and the two RNA-binding domains in the P7 protein were identified. Domain 1 was located in the residue 128-249 containing 122 amino acids and domain 2 was located in the residue 325-355 containing 31 amino acids. Thus, these two domains may play an important role in the virus particle assembly by contributing to the packaging of viral dsRNAs inside the particles. The two domains may be novel RNA-binding domains, because no amino acid sequences highly similar to the conservative sequences of known dsRNA-binding domains reported so far. The similarity between the motif of domain 1 and the motif of the DNA-binding protein suggests that the DNA-binding activity of the RDV P7 protein may be due to this sequence. The similarity between the motif of domain 1 and the motif of the RNA polymerase domain suggests that the P7 protein may also play a role in RNA synthesis, besides its function in the assembly and subsequent packaging of viral dsRNA into core particles.     

Microbial carbonate precipitation in construction materials: A review

Evidence of microbial involvement in carbonate precipitation has led to the exploration of this process in the field of construction materials. One of the first patented applications concerned the protection of ornamental stone by means of a microbially deposited carbonate layer, i.e. biodeposition. The promising results of this technique encouraged different research groups to evaluate alternative approaches, each group commenting on the original patent and promoting its bacterial strain or method as the best performing. The goal of this review is to provide an in-depth comparison of these different approaches. Special attention was paid to the research background that could account for the choice of the microorganism and the metabolic pathway proposed. In addition, evaluation of the various methodologies allowed for a clear interpretation of the differences observed in effectiveness. Furthermore, recommendations to improve the in situ feasibility of the biodeposition method are postulated. In the second part of this paper, the use of microbially induced carbonates as a binder material, i.e. biocementation, is discussed. Bacteria have been added to concrete for the improvement of compressive strength and the remediation of cracks. Current studies are evaluating the potential of bacteria as self-healing agents for the autonomous decrease of permeability of concrete upon crack formation.     

Utilization of modified waste from the antibiotic industry for the production of construction materials

Possible utilization of treated streptomycin fermentation broth modified with waste hydrochloric acid solution followed by lime neutralization was studied. Such a complex additive to concrete increased its strength by 36-41 per cent. With saving cement by 7 per cent the concrete strength increased by 22-29 per cent as compared to the control samples. Therefore, utilization of antibiotic industry waste in production of building material allowed not only to improve its quality but also to lower the environmental pollution.     

Restricted access materials and large particle supports for on-line sample preparation: an attractive approach for biological fluids analysis

An analytical process generally involves four main steps: (1) sample preparation; (2) analytical separation; (3) detection; and (4) data handling. In the bioanalytical field, sample preparation is often considered as the time-limiting step. Indeed, the extraction techniques commonly used for biological matrices such as liquid-liquid extraction (LLE) and solid-phase extraction (SPE) are achieved in the off-line mode. In order to perform a high throughput analysis, efforts have been engaged in developing a faster sample purification process. Among different strategies, the introduction of special extraction sorbents, such as the restricted access media (RAM) and large particle supports (LPS), allowing the direct and repetitive injection of complex biological matrices, represents a very attractive approach. Integrated in a liquid chromatography (LC) system, these extraction supports lead to the automation, simplification and speeding up of the sample preparation process. In this paper, RAM and LPS are reviewed and particular attention is given to commercially available supports. Applications of these extraction supports, are presented in single column and column-switching configurations, for the direct analysis of compounds in various biological fluids.     

Microfluidic synthesis of composite cross‐gradient materials for investigating cell–biomaterial interactions

Combinatorial material synthesis is a powerful approach for creating composite material libraries for the high‐throughput screening of cell–material interactions. Although current combinatorial screening platforms have been tremendously successful in identifying target (termed “hit”) materials from composite material libraries, new material synthesis approaches are needed to further optimize the concentrations and blending ratios of the component materials. Here we employed a microfluidic platform to rapidly synthesize composite materials containing cross‐gradients of gelatin and chitosan for investigating cell–biomaterial interactions. The microfluidic synthesis of the cross‐gradient was optimized experimentally and theoretically to produce quantitatively controllable variations in the concentrations and blending ratios of the two components. The anisotropic chemical compositions of the gelatin/chitosan cross‐gradients were characterized by Fourier transform infrared spectrometry and X‐ray photoelectron spectrometry. The three‐dimensional (3D) porous gelatin/chitosan cross‐gradient materials were shown to regulate the cellular morphology and proliferation of smooth muscle cells (SMCs) in a gradient‐dependent manner. We envision that our microfluidic cross‐gradient platform may accelerate the material development processes involved in a wide range of biomedical applications. Biotechnol. Bioeng. 2011; 108:175–185. © 2010 Wiley Periodicals, Inc.     

Life cycle assessment comparison among different reuse intensities for industrial wooden containers

Goal, scope and background  The industrial packages sector has great importance for the transport sector in Europe. These containers, mainly wooden pallets and spools, are subject to European legislation, which promotes their reuse and recycling. This study uses life cycle assessment (LCA) to assess the environmental impact of the current management system in this sector and the benefits and drawbacks of different reuse intensities as a waste prevention strategy as opposed to the recycling option. Materials and methods  In this paper, four case studies located in Spain and representative of the wooden package sector in Europe are analysed: high reuse pallet, low reuse pallet, low reuse spool and null reuse spool. For the LCA study cases, the functional unit is that required to satisfy the transport necessity of 1,000 t by road. The impact and energy consumption assessment methods used are CML 2 Baseline 2000 and Cumulative Energy Demand. Data are mostly provided by the leading enterprises and organisations in this sector. Results  The paper provides, as a first result, a comprehensive inventory of the systems under study. Secondly, our assessment shows that the systems with higher reuse intensity show a reduction in energy and wood consumption and all the environmental impact categories except for the global warming potential from 34.0% to 81.0% in the pallet study cases and from 50.4% to 72.8% in the spool ones. This reduction is at the expense of the maintenance stage, which on the contrary increases its impact, although it is still relatively small—less than 7% in all the impact categories and flow indicators of the study cases. The highest impact stages are transport, raw material extraction and the process chain. The final disposal and maintenance stages are the lowest impact, contributing at most to less than 30% of the impact in the pallet study cases and 10% in the spool cases. Discussion  Wood consumption (WC), directly related to the number of containers needed to satisfy the functional unit, is the main factor in determining the impact of the stages, especially in the raw materials extraction and process chain stages, assuming that these are undertaken with the same technologies in all the case studies. Other variables, such as the management system, the maintenance index and the final disposal scenario, affect the impact of the remaining stages: transport, maintenance and final disposal. The global warming potential results obtained demonstrate the environmental benefits of using containers made of a renewable resource such as wood instead of using other materials, but these results are not expected to prioritise the lower reuse systems because of their better performance in this category. Conclusions  Reuse, a strategy capable of reducing the environmental impacts of the wooden container systems, is preferable to recycling, while the package maintenance tasks are still feasible. Therefore, reuse, combined with recycling as final disposal, should be encouraged to reduce the demand for natural resources and the waste generated. Recommendations  Based on these results, attention should be paid to the maintenance stage, which, being the lowest-impact one, could substantially reduce the impact of the remaining stages.