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Over the past decade, electronic parts have become smaller, more complex, and highly functional. This is well understood for many products within the consumer and handheld markets. Miniaturization, however, is also impacting sectors such as aerospace and automotive, pushing the limits of already harsh environments. As more power is driven through active devices, the integrity of materials used to provide the electrically conductive interfaces is becoming increasingly critical. For many applications, adhesive films have been the preferred material because they offer a variety of performance and operational advantages such high electrical and thermal conductivity, uniform bondlines, superior adhesion, and low processing temperatures. Today, as miniaturization pushes power-density limits and although devices are also being exposed to high operating temperatures, even for traditionally robust adhesive films, it is challenging to cope with these conditions. In sectors such as aerospace where high reliability is essential, material capability must evolve to deliver on fail-safe performance expectations. This study compares the performance of an established and widely used electrically conductive film adhesive with that of a newly developed film designed to provide improved mechanical performance over a higher elevated temperature range.

Major market demands and packaging trends are driving the continued miniaturization, high functionality requirements for semiconductor devices. To make these new designs feasible in application, they are expected to deliver robust thermal management with good heat dissipation, increased performance and higher reliability. For certain sectors, such as automotive, extremely high reliability is a prerequisite in order to meet the market's strict safety guidelines and performance objectives. Die attach paste adhesives are used to bond electrically active die to metal or composite substrates. To achieve high thermal conductivity, formulation protocols use different filler packages (e.g., metals or inorganic fillers) that are mixed into a polymer matrix, generally with very high filler loading. Especially for automotive packages, die attach adhesives need to pass harsher environmental testing, not only enduring more temperature cycling for a wider application temperature range, but also for longer periods of time and at higher storage temperatures (as high as 200° C). Fillers play a critical role in electrically insulating, high thermal conductivity die attach paste adhesive applications. These applications also require materials that can provide tight bond line thickness control, good adhesion and stress management to pass all reliability tests for high UPH manufacturing. This paper will present results from a die attach paste filler study. The pastes' filler technology was evaluated to understand the impact of different novel filler materials, filler loading percentages, particle size range, particle surface area and surface chemical treatment to analyze their performance within high reliability automotive applications that require high thermal conductivity.

Aims In this study, we evaluated the therapeutic efficacy of selected probiotics in a mouse model of birch pollen (BP)-induced allergic rhinitis. Methods and Results Oral administration of lactobacillus plantarum CJLP133 and CJLP243 ameliorated the symptoms of BP-induced allergic rhinitis by reducing airway hyperresponsiveness (AHR), and both the histological scores and the number of infiltrated cells in the nasal cavities and lungs. Compared with those from vehicle-treated mice, bronchoalveolar lavage (BAL) fluid and draining lymph node samples from CJLP133 and CJLP243-administrated mice showed diminished numbers of immune cells, increased secretion of a Th1-type cytokine (IFN-γ), and decreased production of Th2-type cytokines (IL-4, IL-5 and IL-13). Consistent with these results, levels of IL-4, IL-5, IL-13, serum IgE, and BP-specific serum IgG1 were decreased, whereas secretion of IFN-γ and BP-specific serum IgG2a were augmented upon administration of CJLP133 and CJLP243 in mice. Conclusion Oral administration of lactobacillus plantarum CJLP133 and CJLP243 alleviates symptoms of BP-induced allergic rhinitis in mice by recovering Th1/Th2 balance via enhancement of the Th1-type immune response. Significance and Impact of the Study Lactobacillus plantarum CJLP133 and CJLP243 have therapeutic effects on BP-induced allergic rhinitis in an animal model. This article is protected by copyright. All rights reserved.

Several syntheses have been performed to allow the growth of zeolite crystals on α-silicon carbide supports (α-SiC). Silicon-carbide foams exhibit a duplex macroporous structure. MFI and ANA zeolites have been successfully coated on this relatively inert material. While the synthesis of MFI/SiC required the presence of an additional Si-containing source, in contrast, ANA/SiC composites have been unexpectedly obtained through the self-recrystallization of the silicon contained in the α-SiC substrate. In addition, the size of icositetrahedral ANA crystals was controlled to nearly 35 μm, thanks to SiC open cells templating effect. The different composite materials were thoroughly characterized by SEM, complete textural analysis and XRD. The amount of zeolite coating as well as the coverage by ANA zeolite crystals on SiC surface were determined by both SEM observations and adsorption measurements.

Fatigue strength and life of weldment at high temperatures are important for the materials in power plants. The fatigue crack growth rate is accelerated by oxidation. Similarly, the high-temperature fatigue life is influenced by oxidation. The base metal, the weld metal and the heat-affected zone (HAZ) of the P122 (Cr–Mo steel) weldment were oxidized between 600 °C and 700 °C for up to 500 h in air, and their oxidation behavior was examined. The oxidation resistance increased in the order of HAZ, base metal and weld metal. The scales were mainly Fe 2 O 3 . Fatigue tests were performed to measure the fatigue crack growth rate in the range of low stress intensity factor, and the results are discussed from the viewpoint of different microstructures and oxidation.

Starting from elemental bismuth, tellurium and selenium powders, n-type Bi 2 Te 2.85 Se 0.15 solid solution with fine microstructure was prepared by mechanical alloying (MA) and plasma activated sintering (PAS) in the present work. The effect of PAS process on microstructure and thermoelectric properties of the sintered samples was investigated. The sintering temperature of PAS process (683 K) was 80–100 K lower than that of conventional hot pressing and the whole PAS process was also greatly shortened to about 30 min. A preferentially orientated microstructure with the basal planes (0 0 l ) perpendicular to pressing direction was formed in the PASed sample and the maximum figure of merit ( Z ) at room temperature was 1.80 × 10 −3 K −1 .

In the present work, starting from elemental bismuth, antimony and tellurium powders, p-type 25%Bi2Te3–75%Sb2Te3 thermoelectric materials with high density were prepared by mechanical alloying (MA) and plasma activated sintering (PAS). The single phase 25%Bi2Te3–75%Sb2Te3 alloys were obtained after MA for 12 h. The effect of sintering temperatures on microstructure and thermoelectric properties of the as-PASed samples was researched. Highly compact samples with relative density over 99% could be obtained when sintering temperature was over 653 K. A preferentially orientated microstructure with the (1 1 0) plane parallel to and the basal planes (0 0 l) perpendicular to the pressing direction was formed, and the orientation factors of the (0 0 l) planes changed from 0.11 to 0.12 at different sintering temperatures. The maximum power factor and figures of merit (Z) at room temperature were 3.10 × 10−3 W m−1 K−2 and 2.85 × 10−3 K−1, respectively. The Vickers microhardness reached 112.7 Hv, which was twice that of the single crystal samples prepared by zone-melting.

This study was conducted to develop a method for estimation of CA storage condition by measuring respiration characteristics of fresh products and subjecting the experimental data to statistical analysis. It is possible that respiration characteristics of fresh products (CO2 evolution, O2 consumption and ethanol accumulation, etc.) are fitted to a polynomial equation used in the Response Surface Methodology (RSM). Cherry tomatoes were selected as samples to test the estimation method, which used statistical analysis of respiration characteristics for determining CA storage conditions. The regression equations fitted well with the experimental data of the respiration characteristics having a coefficient of determination R2>0.8. In cherry tomatoes, the CA storage condition was estimated and carried out using the developed method. The effective CA conditions for cherry tomatoes were estimated at 4∼6% O2 and 3.5∼10% CO2. Under these conditions, the storage quality and sensory evaluation of cherry tomatoes were satisfactory. The CA storage of cherry tomatoes was successfully conducted without gas injury and occurrence of off-flavors.

Aim: Lactic acid bacteria (LAB) are beneficial micro-organisms that have been associated with several probiotic effects in both humans and animals. Here, using proteome analysis, we investigate the antitumour effects of cell-bound exopolysaccharides (cb-EPS) isolated from Lactobacillus acidophilus 606 on colon cancer cells and explore the proteins critical for their antitumour activity. Methods and Results: cb-EPS inhibited the proliferation of HT-29 colon cancer cells by directly affecting cell morphology and not the cell cycle. Using two-dimensional polyacrylamide gel electrophoresis coupled with matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF/MS) and immunoblot analysis, we found that cb-EPS dramatically induced Beclin-1 and GRP78, and affected Bcl-2 and Bak regulation. Conclusions: The results of this study indicate that cb-EPS are antitumourigenic against HT-29 colon cancer cells and that this activity is because of the activation of autophagic cell death promoted directly by the induction of Beclin-1 and GRP78, as well as indirectly through the induction of Bcl-2 and Bak. Significance and Impact of the Study: These results may contribute to understanding the novel mechanisms by which probiotic bacteria induce tumour cell death via autophagy.

A method by which the three-dimensional displacements and strains (stresses) of a vibrating clamped rectangular cantilever plate can be calculated from three interferograms is presented. The three-dimensional displacements and strains obtained by the time-averaged holographic interferometry are compared with those calculated by the finite element method. There is good agreement between the two.

For 3 minute umbral oscillations we have considered a two-mode resonant model with the resonance of each mode occurring separately in cavities of the photosphere and chromosphere. The model has been investigated by calculating the transmissions of the waves propagating through the cavities of the umbral photosphere and chromosphere of 3 different model atmospheres (Staude, 1982; Beebe et al. 1982; Avrett 1981). The computed resonant periods, transmission spectra and kinetic energy density of the waves associated with the oscillations are presented for comparison with observations.