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Several genome-wide linkage analyses of different families are conducted to identify the genetic loci and possible candidate genes of congenital long QT syndrome, a hereditary disorder. The results demonstrate that the Kir3.4 mutation plays an extremely significant role in the etiology of the disorder.

4-Demethylepipodophyllotoxin 7'-O-β-D-glucopyranoside (4' DPG), a new podophyllotoxin glucoside with a chemical structure similar to that of 4-demethylpicropodophyllotoxin 7'-O-β-D-glucopyranoside (4DPG), was isolated from the rhizomes of Sinopodophyllum emodi (Wall.) Ying (Berberidaceae). Like 4DPG and etoposide (VP-16), 4' DPG displayed dose--and time-dependent cytotoxic effects in Hep[G.sub.2] cells. Flow cytometric analysis demonstrated the presence of apoptotic cells and DNA fragmentation after Hep[G.sub.2] cells were exposed to 4' DPG (1 µmol/L). In addition, 4' DPG-driven apoptotic events were associated with upregulation of Bax and downregulation of Bcl-2. These results suggest that 4' DPG has prominent cytotoxic activity and induces apoptosis by increasing the ratio of Bax to Bcl-2 in Hep[G.sub.2] cells. Key words: podophyllotoxin, apoptosis, Hep[G.sub.2], Bax, Bcl-2. Le 4-deemeethyleepipodophyllotoxine 7'-O-β-D-glucopyranoside (4' DPG), un nouveau glucoside de la podophyllotoxine ayant une structure chimique similaire au 4-demeethylpicropodophyllotoxine 7'-O-β-D-glucopyranoside (4DPG), a ete isole; des rhizomes de Sinopodophyllum emodi (Wall.) Ying de la famille des Berbericidacece. Comme VP-16 et 4DPG, 4' DPG a eu des effets cytotoxiques dependants de la dose et du temps dans les cellules Hep[G.sub.2]. La cytometrie de flux a revele la presence de cellules apoptotiques et la fragmentation de l'ADN lorsque les cellules Hep[G.sub.2] ont ete exposees a 4' DPG (1 µmol/L). L'analyse a aussi indique que les eveenements apoptotiques induits par 4' DPG etaient associesa une subexpression de Bax et a une perte d'expression de Bcl-2. Ces resultats ont demontre que 4' DPG a eu une forte activite cytotoxique et qu'il pourrait induire l'apoptose en augmentant le rapport Bax/Bcl-2 dans les cellules Hep[G.sub.2]. Mots-cles: podophyllotoxine, apoptose, Hep[G.sub.2], Bax, Bcl-2. [Traduit par la Redaction], Introduction Searching for new drugs is a time-consuming and expensive process. Natural products have long been important sources of potential anticancer drugs, and more than 1000 plant species have been [...]

Antioxidant amperometric sensors based on iron-containing complexes and protein modified electrodes were developed. Indium tin oxide glass was printed with Ti[O.sub.2] nanoparticles, onto which iron-containing compounds and protein were adsorbed. When applied with negative potentials, the dissolved oxygen is reduced to [H.sub.2][O.sub.2] at the electrode surface, and the [H.sub.2][O.sub.2] generated in situ oxidizes [Fe.sup.II] to [Fe.sup.III], and then electrochemical reduction of Fem therefore gives rise to a catalytic current. In the presence of antioxidants, [H.sub.2][O.sub.2] was scavenged, the catalytic current was reduced, and the decreased current signal was proportional to the quantity of existing antioxidants. A kinetic model was proposed to quantify the [H.sub.2][O.sub.2] scavenging capacities of the antioxidants. With the use of the sensor developed here, antioxidant measurements can be done quite simply: put the sensor into the sample solutions (in aerobic atmosphere), perform a cathodic polarization scan, and then read the antioxidant activity values. The present work can be complementary to the previous studies of antioxidant sensor techniques based on OH radicals and superoxide ions scavenging methods, but the sensor developed here is much easier to fabricate and use.

Dental teams treated patients with facial injuries after the May 12, 2008 earthquake in Sichuan province, China. Creating oral and maxillofacial surgeon and dentist reserves can help improve disaster response especially since facial injuries make up a significant portion of earthquake-related injuries.

A physical description of two specific aspects in drain-extended MOS transistors, that is, quasi-saturation and impact-ionization effects, is described and these factors are attributed to the Kirk effect. The model is validated by MATLAB program and has displayed excellent scalability for various transistor dimensions, drift-region doping concentration and voltage-handling capability.

A 500 kJ compact pulsed power supply (PPS) system used for electromagnetic railgun (EMG) system has been developed to investigate the influence of electric parameters on muzzle velocity in the paper, from which the stability and reliability of the PPS system can be evaluated. The pulsed power supply system consists of ten modules, and each module is composed of a high energy density capacitor, a triggered vacuum switch, a pulse shaping inductor, a dump resistor and a crowbar. Influence of different parameters on the velocity was analyzed by ATP simulations in this paper. The parameters include capacitance, equivalent series resistance (ESR) of the capacitor, inductance, natural electric parameter and jitter time of the TVS. The ESR and natural electric parameters are critical influencing factors by comparing the simulation and experimental results. In the end, muzzle velocity deduced by the current, which is obtained from a new model of actual circuit, is about twenty percent lower than that in ideal condition. It is pointed out that the velocity error is mostly caused by ESR and natural electric parameter. Index Terms--Electromagnetic railgun (EMG), equivalent serial resistor (ESR), pulse forming network (PFN), pulsed power supply (PPS) system.

High current switch is a key component of a pulsed power source. Triggered vacuum switch (TVS) possesses many advantages including wide range of operating voltage, compact structure, low cost and so on, so it is considered as one of the most compelling switch in pulsed power system. This paper describes two types (A and B) of TVS samples with different main electrodes and triggering electrodes. Based on theoretical analysis and experimental results, the triggering characteristics of TVS samples have been researched. The triggering polarity, triggering energy and operating voltage influence the triggering delay and the jitter of delay. To recover the failure of TVS samples caused by decreased triggering energy, series air gap was tried. In the lifetime test, the resistance between the triggering electrodes dropped gradually, leading to the failure of TVS. Both types of TVS have discharges number of 100 shots with 70 kA peak current. The ablation on the main electrodes of type B TVS was slighter than that of type A. Index Terms--Component, high current, lifetime, triggered vacuum switches (TVS), triggering characteristics.

Different Escherichia coli serogroups and 11 genes encoding adhesion factors associated with postweaning diarrhea (PWD) and edema disease (ED) is developed for the identification of related serogroups and virulence gene patterns. The resulted output can be readily used to screen the presence of PWD and ED associated Escherichia coli in porcine feces samples.

Several thermoluminescence and position annihilation techniques are used to study and investigate the various defects induced by [Nd.sup.3+], which are very important to improve the persistent luminescence properties of Ca[Al.sub.2][O.sub.4]:[Eu.sup.2+] compound. The analysis reveals that the trap levels in such doped-compounds are much deeper than the normal compounds and constitutes of vacancies, as well as anions.

A study was conducted to observe the quenching effect of the photoluminescence of 1,2,4,5-tetrakis(4-pyridylvinyl)benzene in the presence of CdS colloids stabilized by inverse micelles. An increase in the two-photon absorption cross section and in the two-photon-induced fluorescence intensity was observed for the composite solution when pumped by 740-nm laser irradiation.

A study was conducted to identify endogenous protein enhancers using yeast two-hybrid, coimmunoprecipitation, and finally the enhancement of antifreeze activity. It showed that a thaumatin-like protein from Dendroides canadensis significantly enhances the thermal hysteresis of DAFP-1 and -2 and that glycerol can further enhance this by promoting interaction of antifreeze proteins and thaumatin-like protein.

The role of first intracellular loop (IC1) of the bradykinin B2 receptor (BKB2R) was investigated in terms of their structure and function. The results provide evidence that within the cytosolic face of the BKB2R certain motifs are irreplaceable for signal transduction and help to determine the tertiary structure of the receptor important in its binding of ligand.

An unexpected finding is reported that the Db1 oncoprotein, Cdc42 GTPase, and PAK1 can form a complex through their minimum functional motifs. The Db1-Cdc42-PAK1 complex is sensitive to the nucleotide-binding state of Cdc42 since either dominant negative or constitutively active Cdc42 readily disrupts the ternary binding interaction.

This study focuses on an active monitoring method for damage detection applied to composite structures. Honeycomb sandwich and carbon fiber composite structures are studied. Two kinds of damage are considered: delamination and impact damage. Wavelet analysis methods are adopted to postprocess the raw monitored signal. A new damage signature is introduced to determine the presence and extent of damage in composites, while eliminating the influence of different distances between the active actuator and active monitoring elements. The proposed method is shown to be effective, reliable, and straightforward for the specimens considered in the present study, which are composed of different materials and suffer various levels of damage. An online real-time active monitoring system for damage detection is described that is based on this research. [DOI: 10.1115/1.1547464]

A totally new and independent bacterium is created with a 21 amino acid genetic code is created, which can biosynthesize an abnormal amino acid from fundamental carbon supplies and includes the amino acid in the proteins in relation with the yellowish-brown nonsense codon. Thus, the addition of any such organisms gives a chance to evaluate the result of adding new amino acids to the genetic code, and create proteins with new or increased biological tasks.

The Salmonella enterica rfb gene cluster is responsible for most of this group's O antigen variation. The rfb gene clusters of S. enterica group B and group E1 were characterized and compared. The results showed that the central regions of both groups are divergent although the flanking sequences are conserved. It is proposed that the differences in the central regions are a result of recombination events involving the replacement of one set of genes by another unrelated set, probably by a lateral transfer from species with a low G+C content.

The edge distortion, amplitude asymmetry and transition shift of written tracks, which are induced by the media magnetostatic field, are evaluated using the analytical magnetic force microscopy (MFM) approach. It is shown that the stray fields from the recording layer can result in written tract distortions in the writing process using the analytical magnetic force microscopy (MFM) approach.

An FFT-Filtering-IFFT technique, based on magnetic force microscopy (MFM) image analysis, has been employed to extract and then analyze the perpendicular media noise and its characteristics at various linear densities. The experimental results from examined media indicate that the predominant media noise at high recording density originate from a magnetic cluster formation and coarsening process, suggesting that one of the present difficulties for achieving high linear density in perpendicular recording scheme resides in the head/media writeability issues. Index Terms--Head field gradient, magnetic clusters, magnetic force microscopy, perpendicular media noise, perpendicular recording, recording media, writeability.

Micromagnetic recording model is use for examining the effect of intergranular exchange coupling in high density perpendicular recording. The increase in intergranular exchange coupling at high linear density increases media noise and amplitude modulation while high saturation field, low nucleation field and large transition curvature are induced by smaller exchange coupling.

A hybrid transmission line-micromagnetic model for a shielded MR read head is described. The hybrid model is found to agree closely with a conventional micromagnetic model for magnetization distributions in the sensor.

Dynamin 3, which has important functions is neuronal synapses, has shared the self-assembly and GTPase activation characteristics of dynamin 2. Dynamin proline/arginine-rich domains have mediated interactions with SH3 domain-containing proteins and have regulated both self-association and heteroassociation of dynamics.

The studies about the photoinduced reactions of the 1,2-dicarbonyl compounds phenanthrenequinone (PQ), 1-acetylisatin (IS) and benzil (BZ) with the oxazoles are discussed. Regio- and diastereoselectivity in the [2 + 2] and [4 + 4] cycloadditions based on the thermodynamic stability of the relevant triplet diradical intermediates and the conformations of these diradicals suitable for the intersystem crossing process are also discussed.

The various dynamical processes and mechanisms involved in the nonradiative interionic energy transfer taking place in the [Y.sub.3][Al.sub.5][O.sub.12]:[Ce.sup.3+], [Pr.sup.3+] phosphor are analyzed. The electric dipole-dipole interaction is shown to be the main governing factor for the energy transfer taking place from the lowest state of the compound.

Series of rectangular-shaped DNA origami tiles in which parallel DNA helices are arranged in a zigzag pattern when viewed along the DNA helical axis were constructed to determine the important factors involved in the assembly of DNA origami superstructures. The findings from atomic force microscopy imaging revealed that the dimensional aspect ratio of the origami unit tiles and intertile connection design play important roles in determining the final higher-order structures obtained from DNA origami tiles.

Phenylchlorocarbene has formed highly stable [pi]-type complexes with 1,3,5-trimethoxybenzene in pentane and the carbene and carbene complexes are in equilibrium. The equilibrium constant is measured and the carbene complexes are characterized by UV-vis spectroscopy and computational analysis.

PCR-restriction fragment length polymorphism (RFLP) was used to identify the putative Proteus O antigen locus and sequences of 40 Proteus isolates were compared to demonstrate the high degree of heterogeneity in this region. The analysis identified five putative Proteus O antigen gene clusters and proposed the probable functions of O antigen-related genes based on their similarity to genes in the available databases.

The multiferroic composites with nominal stoichiometry [Bi.sub.0.8][Dy.sub.0.2][Fe.sub.1-y][Ti.sub.y][O.sub.3+[delta]] are prepared by adding Ti to [Bi.sub.0.8][Dy.sub.0.2]Fe[O.sub.3] via a two-stage solid-state reaction method. The simultaneously enhanced ferroelectric and magnetic properties achieved in composites due to the existence of ferrimagnetic insulated [Dy.sub.3][Fe.sub.5][O.sub.12] have implications for studies on BiFe[O.sub.3] based materials.

A five-step synthesis of a TRPV1 receptor antagonist is described. The key step in the reaction includes a novel palladium-catalyzed amidation reaction of 4-chloro-1-methylindazole with the benzyl urea to form the unsymmetrically substituted urea.

The studies have shown that 375 nm excitation of arylchlorodiazines has furnished their [S.sub.1] excited states with lengthened C-N bonds, a positive charge at the para and diazirine carbon atoms and a negative charge at the nitrogen atoms. The structures have rationalized the solvent and substituent effects on the excited state lifetimes.

The significant covalent bonding character in the Au-C bonds in Au[(CN).sub.2.sup.-] is studied by using photoelectron spectroscopy and is compared with its lighter congeners (Ag[(CN).sub.2.sup.-] and Cu[(CN).sub.2.sup.-]). The covalent character in the Au-C bonding because of the strong relativistic effects is shown in Au[(CN).sub.2.sup.-], consistent with its high stability.

An enhanced nonsense suppression system was employed to incorporate the nonnatural amino acid p-benzoyl-L-phenylalanine (pBpa) throughout the transcriptional activation domain of the prototypical eukaryotic transcriptional activator Gal4 in vivo (S. cerevisiae). The functional studies of the pBpa-containing Gal4 mutants provide insight into the impact of such substitution on the essential binding interface of Gal4 to maintain both transcriptional activity and sensitivity to growth conditions.