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An electrostatic precipitator (ESP) based personal sampler with a laboratory based electrowetting-on-dielectric (EWOD) concentrator could provide a high concentration rate personal aerosol sampler system. A prototype system has been developed based on the concept of a lightweight personal ESP collecting aerosol particles onto a hydrophobic surface followed by the use of an EWOD actuated droplet system to transfer the deposited sample into a microlitre size water droplet.A personal sampler system could provide military or civilian personnel with a wide area biological monitoring capability supplying information on who has been infected, what they have been infected with, how much material they were exposed to and possibly where and when they were infected. Current commercial-off-the-shelf (COTS) personal sampler solutions can be bulky and use volumes of water to extract the sample that are typically a thousand times greater than the proposed method.Testing of the prototype ESP at a sample flow rate of 5Lmin−1 demonstrated collection efficiencies greater than 80% for sodium fluorescein particles larger than 4μm diameter and of approximately 50% at 1.5μm. The ESP-EWOD system collection efficiency measured for Bacillus atrophaeus (BG) spores with an air sample flow rate of 20Lmin−1 was 2.7% with a concentration rate of 1.9×105min−1. This was lower than expected due to the corona ions from the ESP affecting the hydrophobicity of the collection surface and hence the EWOD efficiency. However, even with this low efficiency the concentration rate is more than an order of magnitude higher than the theoretical maximum of the best current COTS personal sampler. For an optimised system, ESP-EWOD system efficiency should be higher than 32% with a comparable increase in concentration rate.

In continuation of an experimental investigation reported earlier by the authors on bolted moment joints in ferrocement construction, this study regards (1) further testing of ten such joints to broaden the range of the principal parameters – thickness of the connected ribs and location of bolts and (2) simple analytical modeling for design. Test results, as presented and discussed in this paper, indicate that the mode of failure of a joint depends on whether the applied moment is in the opening or closing mode. Under the closing mode, failure always occurs by shear punching of the bearing plates through the connected ribs. In contrast, failure in the opening mode occurs by bending failure of either the connected or the longitudinal rib. Based on observed failure modes, expressions have been derived for predicting the strength of such a joint. A comparison of theoretical predictions with present test results and those reported earlier shows good agreement.

Nafion® is frequently used as electrolyte membrane in polymer electrolyte fuel cells (PEFC). In this Letter the degradation of the Nafion® polymer electrolyte was investigated using X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). XRD showed that the electrode potential and low gas humidification temperature could decrease the crystallinity of Nafion®. XPS analysis indicated that the Nafion® was decomposed in the hydrogen potential region of the fuel cell, through the interaction of the hydrophobic (CF2)n groups of the membrane with H or/and C atoms.

Interaction between transition metals Co, Fe and Ni and carbon materials, such as multi-walled carbon nanotubes (MWNTs), single-walled carbon nanotubes (SWNTs), activated carbon (AC) and layered graphite (LG), has been investigated at high temperatures. Complete wetting for AC, partial wetting for MWNTs, and almost no wetting for SWNTs and LG have been observed, respectively. It is found that the defects in the carbon materials play a key role in the interaction.

Certain BH3-only proteins transiently bind and activate Bak and Bax, initiating their oligomerization and the permeabilization of the mitochondrial outer membrane, a pivotal step in the mitochondrial pathway to apoptosis. Here we describe the first crystal structures of an activator BH3 peptide bound to Bak and illustrate their use in the design of BH3 derivatives capable of inhibiting human Bak on mitochondria. These BH3 derivatives compete for the activation site at the canonical groove, are the first engineered inhibitors of Bak activation, and support the role of key conformational transitions associated with Bak activation.

It was found that the addition of molybdenum to Co/MgO catalysts could remarkably increase the yield and also improve the quality of single-walled carbon nanotubes (SWNTs) from catalytic decomposition of methane. The generation rate of SWNTs was raised at least 10 times and the formation of amorphous carbon was suppressed. But there is an optimum content of Mo and Co, beyond which multi-walled carbon nanotubes (MWNTs) were formed. In other words, the relative amount of SWNTs and MWNTs could be controlled by the composition of catalysts. The obtained SWNTs showed a very high BET surface area. The promotion role of molybdenum was discussed.

In this Letter, we report that after oxidation in air and reduction in hydrogen the existing carbon nanotube arrays can be used as a substrate to grow another nanotube array. The two arrays are connected through a thin catalyst layer. Micro-Raman study of these two nanotube arrays shows that they have different characteristic spectra. Besides the small shift in the peak frequencies of the two kinds of arrays in Micro-Raman spectra, we have observed changes in the relative intensities of D, G and D ′ lines and proposed the mechanism of this phenomenon.

In this Letter, we report the growth of carbon nanofibers arrays by chemical vapor deposition in the presence of magnetic force. We find that when a magnet is applied carbon nanofibers arrays are grown and when the magnet is absent carbon nanotubes arrays are grown at the same experimental conditions. The nanofibers are worse in alignment and less in graphitization than those of the nanotubes grown at the same conditions. What is interesting is that two or three nanofibers can be connected together through a catalyst nanoparticle. These connections might be useful, especially in the fabrication of nanoelectronic devices.

Chemical modification of emeraldine (EM) based powders via thermally induced surface graft copolymerization with acrylic acid (AAc), 4-styrenesulfonic acid (SSAc) and amphoteric N,N′-dimethyl(methacryloylethyl)ammonium propanesulfonate (DMAPS) was carried out in aqueous media. The effects of temperature on graft copolymerization and Mohr's salt on homopolymerization were also studied. The chemical composition and structure of the graft-copolymerized powders were studied by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy. In all cases, the graft yield increased with the monomer concentration and the temperature used for graft copolymerization. Certain Mohr's salts effectively inhibited the production of the homopolymers. Graft copolymerization with AAc and SSAc readily gave rise to self-protonated and semi-conductive EM powders, with the conductivity increasing with the extent of grafting. However, steric hindrance and spatial configuration of the grafted chains had substantially limited the extent of protonation of the EM substrate by the protonic acid functional groups of these chains.

A simple technique of thermal graft copolymerization of 1-vinyl imidazole (VIDZ) in the presence of a small amount of a crosslinking agent (XLA) on plasma-pretreated polyimide (PI or Kapton HN®) films with simultaneous lamination of copper foils was demonstrated. The simultaneous thermal grafting and lamination process was carried out in the temperature range of 80–150°C under atmospheric conditions and in the complete absence of a polymerization initiator. Significant improvement in adhesion was achieved by the presence of a XLA, such as 2,4,6-triallyloxy-1,3,5-triazine (TATZ), or 1,3,5-triallyl benzene tricarboxylate (TBTC), in VIDZ during the thermal graft copolymerization and lamination process. T-peel adhesion strength exceeding 17 N/cm can be readily achieved for the polyimide–copper interface for grafting and lamination carried out at the reduced temperature of 100°C. The T-peel adhesion strengths are reported as a function of the cooling rate, the argon plasma pre-treatment time of the polyimide films, the thermal lamination temperature, and the thermal lamination time. The polyimide–copper interface graft copolymerized and laminated in the presence of a XLA also exhibited substantially improved resistance to moisture. The surface compositions of the polyimide films and copper foils from the delaminated interfaces were studied by X-ray photoelectron spectroscopy (XPS). The enhanced interfacial adhesion has resulted in cohesive failure deep inside the PI film as is also revealed by the scanning electron micrograph (SEM).

The use of electroactive polymer–SiO 2 nanocomposites for the uptake of gold and palladium from AuCl 3 and PdCl 2 in acid solutions respectively was investigated. The electroactive polymers used were polyaniline (PAN) and polypyrrole (PPY). The change in the physicochemical properties of the nanocomposites with metal uptake were of particular interest. In the case of gold uptake, the reaction rate increases with temperature from 0 to 60°C. The accumulation of elemental gold on the nanocomposites increases the diameter and decreases the surface area. The surface Au/N ratio as determined using X-ray photoelectron spectroscopy (XPS) is highly dependent on the rate of reactions even for the same amount of gold uptake. The uptake of palladium from PdCl 2 is much more difficult to accomplish. High rates of uptake can only be achieved with the electroactive polymers reduced to their lowest oxidation state and unlike the case of gold uptake, the palladium on the microparticles does not exist in the elemental form but as a Pd(II) compound.

Introduction Imatinib mesylate (IM) is the first-line treatment and gold standard for treatment of chronic myeloid leukemia (CML). Pharmacokinetic profile of IM and its active metabolite, N-desmethylimatinib (M1) in CML patients are clinically important. Objectives This study aimed to determine the influence of CYP1A2, CYP3A5 and CYP2C19 polymorphisms on the drug response of IM in Asian CML. We also aimed to determine the pharmacokinetic profile for both IM and M1 in CML patients with prescription 400 mg PO. Methodology A total of 250 healthy volunteers (controls) and 50 CML patients (cases) receiving IM were enrolled in a prospective pharmacogenetic study. CYP1A2, CYP3A5 and CYP2C19 polymorphisms were genotyped in both control and case groups using PCR-RFLP. In the pharmacokinetic study, serum IM and M1 concentrations were measured using the validated ultra-high performance liquid chromatography method on first three CML patients with 400 mg IM PO. The χ2 test was used to correlate CYP1A2, CYP3A5 and CYP2C19 genotypes to good responder and resistant group. Results The genotype frequencies of CYP1A2, CYP3A5 and CYP2C19 SNP will be discussed in Malays, Chinese and Indians. In the pharmacokinetic study, we observed high standard deviation (>20% of mean) in volume of distributions (Vd), clearance (CL) and area under curve (AUC) for both IM and M1. For IM, Vd = 113.32 ± 43.52 l, CL = 5.01 ± 1.19 l h-1 and AUC = 62 953.33 ± 9791.38 ng h l-1, whereas for M1, Vd = 415.27 ± 228.72 l, CL = 4.84 ± 3.85 l h-1 and AUC = 5585.15 ± 2950.42 ng h l-1. This preliminary study suggested a high interindividual pharmacokinetic variability in Malaysian CML patients. M1 concentration during steady state (C0) and its time concentration profile were different as per reported in Caucasian population. It suggested that Asians may have a different IM metabolism profile from Caucasians. Summary In short, the preliminary pharmacokinetic data highlighted the potential differences of metabolism profile between Asian and Caucasian. Future validation in a larger sample size is ongoing.

Although in vitro observations indicate that long noncoding RNAs (lncRNAs) regulate innate immune responses, their effect upon immune tolerance in vivo has not been defined. We have identified a novel gene of unknown function for which sequence variation is associated with autoimmune diabetes in the nonobese diabetic (NOD) mouse strain. Bioinformatics and expression analyses indicate this gene encodes a lncRNA that is induced by Toll-like receptor (TLR) activation, localises to the nucleus and cytoplasm of dendritic cells, and binds to proteins within these cellular compartments. Moreover, sequence variation for this gene is associated with altered TLR-mediated cytokine production. Hence this gene was named Apics for Attenuator of Pattern recognition receptor-Induced Cytokine Secretion. To further investigate the function of this lncRNA, we established a C57BL/6 (B6) knockout mouse strain for Apics and discovered that Apics -deficient dendritic cells exhibit enhanced TLR-mediated cytokine production. Apics -deficient B6 mice also exhibit increased susceptibility to autoimmunity in two disease models: experimental autoimmune encephalomyelitis and experimental anti-neutrophil cytoplasmic antibody-associated vasculitis. Our study suggests that lncRNAs, such as Apics , can serve as TLR-inducible repressors that regulate the magnitude of innate immune responses to reduce the risk for developing autoimmune disease.

SRPX2 (Sushi repeat-containing protein, X-linked 2) has recently emerged as a multifunctional protein that is involved in seizure disorders, angiogenesis and cellular adhesion. Here, we analyzed this protein biochemically. SRPX2 protein was secreted with a highly post-translational modification. Chondroitinase ABC treatment completely decreased the molecular mass of purified SRPX2 protein to its predicted size, whereas heparitinase, keratanase and hyaluroinidase did not. Secreted SRPX2 protein was also detected using an anti-chondroitin sulfate antibody. These results indicate that SRPX2 is a novel chondroitin sulfate proteoglycan (CSPG). Furthermore, a binding assay revealed that hepatocyte growth factor dose-dependently binds to SRPX2 protein, and a ligand–glycosaminoglycans interaction was speculated to be likely in proteoglycans. Regarding its molecular architecture, SRPX2 has sushi repeat modules similar to four other CSPGs/lecticans; however, the molecular architecture of SRPX2 seems to be quite different from that of the lecticans. Taken together, we found that SRPX2 is a novel CSPG that is overexpressed in gastrointestinal cancer cells. Our findings provide key glycobiological insight into SRPX2 in cancer cells and demonstrate that SRPX2 is a new member of the cancer-related proteoglycan family.

The relative effectiveness of phototherapy and exchange transfusion for nonhemolytic neonatal hyperbilirubinemia was compared in two closely matched groups of infants. Although the exchange transfusion achieved an immediate reduction of bilirubin level, the "rebound" was rapid and tended to offset this reduction. The more gradual and steady effect of phototherapy resulted in a significantly lower serum bilirubin level at 1, 2, and 3 days after commencement of therapy; the rebound after phototherapy was small. Phototherapy was demonstrated to be more effective than exchange transfusion in achieving prolonged reduction of bilirubin levels for nonhemolytic hyperbilirubinemia. With more efficient lamps delivering more energy in the desired spectrum, it would seem feasible to treat hyperbilirubinemia of whatever etiology with this safer and more convenient form of therapy, though sometimes only as in adjunct therapy.

The efficacy of fluorescent daylight, green, and blue lamps in reducing bilirubin levels was compared in two groups of infants with nonhemolytic hyperbilirubinemia: healthy infants in a term nursery and infants in an intensive care unit. The decline of serum bilirubin concentration was most rapid with the blue lamps, with the duration of exposure required being significantly shorter than that with the other two types of light in both groups. The rate of decline over the first 24 hours, as well as the overall rate of decline for the whole duration of phototherapy, was also significantly greater with the blue lamps, the rate being about twice that for the green lamps in the infants in the intensive care unit; the daylight lamps were intermediate in efficacy. The daylight lamps permitted easy clinical monitoring with minimal side effects, whereas the green and blue lamps were equally disturbing to the attending personnel. The green lamps caused severe erythema and tanning in the initial 200 hours of phototherapy. It appears preferable to use either daylight lamps, which permit enhanced clinical monitoring with adequate efficacy, or special blue lamps, which provide maximal therapeutic effect, rather than green lamps, which offer neither.

The nature of the dose response relationship of phototherapy for neonatal hyperbilirubinemia was studied in 110 infants divided into ten comparable groups; each group was subjected to phototherapy of different intensity. The response to phototherapy increases with increasing dose, but the rate of this response progressively decreases with increasing radiance till a "saturation point" is reached, beyond which no further increase in response occurs to further increase in radiance, i.e., an asymptotic regression was demonstrated. The minimal radiance at which phototherapy begins to be effective for neonatal hyperbilirubinemia was also determined. The rebound after cessation of phototherapy was similar in all groups of infants, despite the shorter duration of exposure required for the groups subjected to intense phototherapy.