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A sensitive and specific method for determination of viaminate in human plasma by using high-performance liquid chromatography coupled with electrospray tandem mass spectrometry (LC-MS/MS) was developed in this study. The plasma samples were simply deproteinated, extracted, evaporated, and then reconstituted in 200 microl of methanol prior to analysis. Chromatographic separation was carried out on a Shimadzu VP-ODS column (250 mm x 2.0 mm, 5 microm) with a mobile phase of methanol-water (95:5, v/v) at a flow rate of 0.2 ml/min. Quantification was performed in the negative-ion electrospray ionization mode by selected ion monitoring of the product ions at m/z 164 for viaminate and m/z 109 for testosterone propionate which was used as the internal standard. The corresponding parent ions were m/z 446 and m/z 345. A linear calibration curve was observed within the concentration range of 0.10-200 ng/ml. The lowest limit of quantitation (LLOQ) was 0.1 ng/ml. The extraction-efficiency at three concentrations was 100.7, 93.6, and 99.7%. Practical utility of this new LC-MS/MS method was confirmed in pilot pharmacokinetic studies in humans following oral administration.

Amphoteric-refracting properties of uniaxial crystals have been both theoretically studied and experimentally observed. In this paper, the theoretical analysis of the amphoteric-refracting property for uniaxial crystals is extended to reflection of light on the basis of previous studies. Theoretical prediction and experimental observation of amphoteric-reflecting properties at the second planar interface of uniaxial crystal slabs are presented. Three possible phenomena relating to combinations of the refraction and the reflection at the second planar interface are discussed: negative refraction with negative reflection, positive refraction with positive reflection, and positive refraction with negative reflection. It is found that negative reflections can occur at a wide angular range in uniaxial crystals by orienting the crystals with their optical axes at a certain angle theta(0) to the normal of the planar interfaces. The maximum angular range for the incident light to yield negative reflections depends on the refractive indices n(o) and n(e). Optical measurements on a YVO4 crystal give good agreement with the theoretical prediction.

An improved approach for increasing the multiplex level of single nucleotide polymorphism (SNP) typing by adapter ligation-mediated allele-specific amplification (ALM-ASA) has been developed. Based on an adapter ligation, each reaction requires n allele-specific primers plus an adapter-specific primer that is common for all SNPs. Thus, only n+1 primers are used for an n-plex PCR amplification. The specificity of ALM-ASA was increased by a special design of the adapter structure and PCR suppression. Given that the genetic polymorphisms in the liver enzyme cytochrome P450 CYP2D6 (debrisoquine 4-hydroxylase) have profound effects on responses of individuals to a particular drug, we selected 17 SNPs in the CYP2D6 gene as an example for the multiplex SNP typing. Without extensive optimization, we successfully typed 17-plex SNPs in the CYP2D6 gene by ALM-ASA. The results for genotyping 70 different genome samples by the 17-plex ALM-ASA were completely consistent with those obtained by both Sanger's sequencing and PCR restriction fragment length polymorphism (PCR-RFLP) analysis. ALM-ASA is a potential method for SNP typing at an ultra-low cost because of a high multiplex level and a simple optimization step for PCR. High-throughput SNP typing could be readily realized by coupling ALM-ASA with a well-developed automation device for sample processing.

Highly c-axis oriented un-doped zinc oxide (ZnO) thin films, each with a thickness of ~ 100 nm, are deposited on Si (001) substrates by pulsed electron beam deposition at a temperature of ~ 320 °C, followed by annealing at 650 °C in argon in a strong magnetic field. X-ray photoelectron spectroscopy (XPS), positron annihilation analysis (PAS), and electron paramagnetic resonance (EPR) characterizations suggest that the major defects generated in these ZnO films are oxygen vacancies. Photoluminescence (PL) and magnetic property measurements indicate that the room-temperature ferromagnetism in the un-doped ZnO film originates from the singly ionized oxygen vacancies whose number depends on the strength of the magnetic field applied in the thermal annealing process. The effects of the magnetic field on the defect generation in the ZnO films are also discussed.

We theoretically and experimentally show that negative refraction can be realized at the surface of conventional uniaxial crystals by orientating the crystals with their optic axes at a certain angle theta(0) to the normal of the light incoming surface. The concept of negative refraction can be extended to be an intrinsic property of all uinaxial crystals. It is revealed that the angular range for incident light to yield negative refraction attains its maximum that only depends on the difference of two indices of refraction vertical bar n(e)-n(0)vertical bar when tan(2) theta(0)=n(0)/n(e). The careful experiments on positive uniaxial crystal YVO4 and negative unaxial crystal calcite (CaCO3) give results in good agreement with the calculated ones. It should be noted that the negative refraction reported here differs from that occurring in metamaterials or photonic crystals in that the wave vector of light k in conventional crystals does not form a left-handed triplet with electromagnetic field E and H.

TiO2 nanorod arrays (TiO2 NRAs) sensitized with CdS nanoparticles were fabricated via successive ion layer adsorption and reaction (SILAR), and TiO2 NRAs were obtained by oxidizing Ti NRAs obtained through oblique angle deposition. The TiO2 NRAs decorated with CdS nanoparticles exhibited excellent photoelectrochemical and photocatalytic properties under visible light, and the one decorated with 20 SILAR cycles CdS nanoparticles shows the best performance. This can be attributed to the enhanced separation of electrons and holes by forming heterojunctions of CdS nanoparticles and TiO2 NRAs. This provides a promising way to fabricate the material for solar energy conversion and wastewater degradation.

We demonstrate a low-loss terahertz waveguide based on the InAs-graphene-SiC structure. By analyzing the terahertz waveguide proposed in this paper, we can obtain that it is the characteristic of a low transmission loss coefficient (αloss ≈ 0.55 dB/m) for fundamental mode (LP01) when the incident frequency is larger than 3.0 THz. The critical radii of the inside and outside cylinders have been found for the high-quality transmission. The large inside radius and the high transmission frequency result in a flat transmission loss coefficient curve. As a strictly two-dimensional material, the double graphene surface rings perform better to improve the quality of transmission mode. These results provide a new idea for the research of the long-distance THz waveguide.

The present work studies the effect of substrate temperature and film composition on the structural and mechanical properties evolution of magnetron sputtered Zr-Ti films. As-deposited films show a monotonically strengthening (0002) crystallographic texture ranging from ambient temperature to 523 K, while then reveal a (0002) texture to randomly orientated structure transition at higher temperature. High Resolution TEM observations reveal a competitive and reconstruction growth mechanism which is in good agreement with the well-known Structure Zone Model. Nano-indentation measurements revealed that texture strengthening contribute to the improvement of mechanical properties. These results suggest that by establishing a semi-quantitative phase diagram based on the Structure Zone Model, structure and structure-related properties modification can be easily realized and precisely controlled by modifying the TS/Tm region during deposition.

TiO2-TiN composite catalysts were prepared by oxidizing the TiN films in air at 350 °C. By adjusting the oxidation time to control the oxidation stage of TiN films, the optical band gap of the TiO2-TiN composites can be varied in a wide range from 1.68 eV to 3.23 eV. These composite films all showed red shift in photo-response towards the visible region, and depending on the optical band gap, some composite films exhibited good catalytic activity in the visible light region. This study provides a simple but effective method to prepare film photocatalyst working in visible light.

We clarified, in this Letter, that in un-doped ZnO single crystals after thermal annealing in flowing argon, the defects-induced room-temperature ferromagnetism was originated from the surface defects and specifically, from singly occupied oxygen vacancies denoted as F+, by the optical and electrical properties measurements as well as positron annihilation analysis. In addition, a positive linear relationship was observed between the ferromagnetism and the F+ concentration, which is in support with the above clarification.

Room-temperature ferromagnetism was achieved in un-doped ZnO films on silicon and quartz substrates. Photoluminescence measurement and positron annihilation analysis suggested that the ferromagnetism was originated from singly occupied oxygen vacancies (roughly estimated as ∼0.55 μB/vacancy), created in ZnO films by annealing in argon. The saturated magnetization of ZnO films was enhanced from ∼0.44 emu/g (on quartz) to ∼1.18 emu/g (on silicon) after annealing at 600 °C, as silicon acted as oxygen getter and created more oxygen vacancies in ZnO films. This study clarified the origin of ferromagnetism in un-doped ZnO and provides an idea to enhance the ferromagnetism.

Room-temperature ferromagnetism was achieved in un-doped ZnO films by annealing the films in flowing argon at 650 °C. The ferromagnetic property of the ZnO films can be manipulated by applying an external magnetic field during annealing, with a maximum of 2.7 emu/g achieved at a field of 7 T, which is almost double that when no magnetic field was applied. The reason is that the magnetic field influenced greatly the involvement of oxygen defects which are origin of the ferromagnetism of these un-doped ZnO films.

ZnO films became ferromagnetic when defects were introduced by thermal-annealing in flowing argon. This ferromagnetism, as shown by the photoluminescence measurement and positron annihilation analysis, was induced by the singly occupied oxygen vacancy with a saturated magnetization dependent positively on the amount of this vacancy. This study clarified the origin of the ferromagnetism of un-doped ZnO thin films and provides possibly an alternative way to prepare ferromagnetic ZnO films.

The structural and physical properties of LiMn2-xFexO4 (x = 0 to 0.5) were investigated. Contrasting LiMn2O4 with LiMn1.5Fe0.5O4, we observed a remarkable difference in the magnetic frustration. The LiMn2O4 sample has a magnetic ordering transition at 61 K while Fe-doped LiMn1.5Fe0.5O4 has an antiferromagnetic ordering transition with a Neel temperature at TN = 34 K. Our result showed a larger value of the frustration index (f=| w|/TC) for pure LiMn2O4 than for LiMn1.5Fe0.5O4. Fe-doping results in a decrease in the degree of frustration. Fe dopants occupying positions of Mn ion can break the original moment equilibrium so as to suppress the magnetic frustration in LiMn2O4.

Transition metal compounds with two-dimensional triangular lattice, such as LiVO2, are of particular interest, because they exhibit peculiar structural and magnetic behavior involving the frustration present in these oxides. An orbital ordering transition occurs near 500 K, which leads to a suppression of magnetic moment below the phase transition temperature Tt. We synthesized a series of Mg-doped LiVO2 single-phase samples and reported their structural and magnetic properties. The samples were characterized by x-ray diffraction, scanning electron microscope, differential scanning calorimetry, electrical resistivity, magnetic susceptibility, and specific heat measurement. For Mg-doped samples Li1−xMgxVO2 (x=0, 0.05, 0.10, and 0.15), the structural analysis show that, with increasing x, the lattice constants change monotonously; in the a-b plane, the lattice expands; while in the c-axis direction, the lattice is compressed. Substitution of Li with Mg ions results in the degeneration of two-dimensional cha...

It is important to prepare ideal 0-3 type magnetoelectric nanocomposites for promoting the multiferroic technological applications; however, the processing technology has become a big challenge. The key point to achieve the synthesis of 0-3 type magnetoelectric composites is the creation of ferromagnetic/ferroelectric composite nanoparticles with core-shell structure. In this work, core-shell structured CoFe2O4/BaTiO3 nanoparticles were synthesized in two steps. CoFe2O4 nanoparticles were firstly prepared through a polyacrylamide gel method, and then were coated with BaTiO3 layers using the same gel route. It is demonstrated that the as-prepared composite particles are an evident core-shell structure, where the core and the shell are determined to be CoFe2O4 and BaTiO3, respectively. The composite particles are nearly spherical in shape with a narrow particle size distribution.

Background Robertsonian translocations occur in approximately one in every 1000 newborns. Although most Robertsonian translocation carriers are healthy and have a normal lifespan, they are at increased risk of spontaneous abortions and risk of producing unbalanced gametes and, therefore unbalanced offspring. Here we reported a previously undescribed Robertsonian translocation. Case Presentation We identified three Robertsonian translocation carriers in this family. Two were heterozygous translocation carriers of 45,XX or XY,der(14;15)(q10;q10) and their son was a homozygous translocation carrier of a 44,XY,der(14;15)(q10;q10), der(14;15)(q10;q10) karyotype. Chromosomal analysis of sperm showed 99.7 % of sperm from the homozygous translocation carrier were normal/balanced while only 79.9 % of sperm from the heterozygous translocation carrier were normal/balanced. There was a significantly higher frequency of aneuploidy for sex chromosome in the heterozygous translocation carrier. Conclusions The reproductive fitness of Robertsonian translocation carriers is reduced. Robertsonian translocation homozygosity can be a potential speciation in humans with 44 chromosomes.

ObjectivesAlthough 1-stop hybrid coronary revascularization offers potential benefits for selected patients with multivessel coronary artery disease, the exposure to contrast dye and potent antiplatelet drugs could increase the risk of postoperative acute kidney injury and coagulopathy. The goal of the present study was to compare the measures of renal function, postoperative bleeding, and transfusion requirements in patients undergoing hybrid revascularization compared with off-pump coronary artery bypass grafting (CABG).MethodsWe retrospectively analyzed the data from 141 consecutive patients who had undergone 1-stop hybrid coronary revascularization from June 2007 to January 2011. Propensity score matching with 141 off-pump CABG patients from our surgical database was performed for comparison. The change in renal function, cumulative chest tube drainage, and clinical outcome parameters were compared between the 2 groups.ResultsCompared with off-pump CABG, patients undergoing hybrid revascularization had significantly less chest tube drainage at 12 hours after surgery (P = .04) and for the total amount during the postoperative period (P

Nanostructured titanium nitride (TiN) films with varying porosity were prepared by the oblique angle deposition technique (OAD). The porosity of films increases as the deposition angle becomes larger. The film obtained at an incident angle of 85° exhibits the best catalytic activity and sensitivity to hydrogen peroxide (H2O2). This could be attributed to its largest contact area with the electrolyte. An effective approach is thus proposed to fabricate TiN nanostructure as H2O2 sensor by OAD.