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A class of finite volume methods is developed for pricing either European or American options under jump-diffusion models based on a linear finite element space. An easy to implement linear interpolation technique is derived to evaluate the integral term involved, and numerical analyses show that the full discrete system matrices are M-matrices. For European option pricing, the resulting dense linear systems are solved by the generalised minimal residual (GMRES) method; while for American options the resulting linear complementarity problems (LCP) are solved using the modulus-based successive overrelaxation (MSOR) method, where the H+-matrix property of the system matrix guarantees convergence. Numerical results are presented to demonstrate the accuracy, efficiency and robustness of these methods.
In this paper, a tri-band bandpass filter (BPF) using asymmetric stub-loaded stepped-impedance resonator (SL-SIR) is presented. The asymmetric characteristic of SL-SIR broadens degrees of freedom for three controllable modes design. Also, the coupling coefficients (Mij) and the external quality factors (Qei) at each passband of the filter can be independently adjusted by the proposed mixed-type feedline structure. Besides, multi-transmission zeros are produced to improve the isolation and selectivity of the passbands. Finally, a tri-band BPF is operated at 1.9 GHz (time division long term evolution – TD-LTE band), 3.2 GHz (worldwide interoperability for microwave access – WiMAX band), and 5.8 GHz (wireless local area networks – WLAN band) and their insertion loss are 1.03, 0.94, and 1.27 dB, respectively. The measured results of the fabricated tri-band BPF exhibit good agreement with simulated results.
A large schizophrenia genome-wide association study (GWAS) and a
subsequent extensive replication study of individuals of European
ancestry identified eight new loci with genome-wide significance and
suggested that the MIR137-mediated pathway plays a role
in the predisposition for schizophrenia.
To validate the above findings in a Han Chinese population.
We analysed the single nucleotide polymorphisms (SNPs) in the newly
identified schizophrenia candidate loci and predicted
MIR137 target genes based on our published Han
Chinese populations (BIOX) GWAS data. We then analysed 18 SNPs from the
candidate regions in an independent cohort that consisted of 3585
patients with schizophrenia and 5496 controls of Han Chinese
We replicated the associations of five markers
(P<0.05), including three that were located in the
predicted MIR137 target genes. Two loci
(ITIH3/4: rs2239547, P
=1.17×10–10 and CALN1: rs2944829,
P=9.97×10–9) exhibited genome-wide
significance in the Han Chinese population.
The ITIH3/4 locus has been reported to be of genome-wide
significance in the European population. The successful replication of
this finding in a different ethnic group provides stronger evidence for
the association between schizophrenia and ITIH3/4. We
detected the first genome-wide significant association of schizophrenia
with CALN1, which is a predicted target of
MIR137, and thus provide new evidence for the
associations between MIR137 targets and
Schistosoma japonicum, a human blood fluke, causes a parasitic disease affecting millions of people in Asia. Thioredoxin–glutathione system of S. japonicum plays a critical role in maintaining the redox balance in parasite, which is a potential target for development of novel antischistosomal agents. Here we cloned the gene of S. japonicum thioredoxin (SjTrx), expressed and purified the recombinant SjTrx in Escherichia coli. Functional assay shows that SjTrx catalyses the dithiothreitol (DTT) reduction of insulin disulphide bonds. The coupling assay of SjTrx with its endogenous reductase, thioredoxin glutathione reductase from S. japonicum (SjTGR), supports its biological function to maintain the redox homeostasis in the cell. Furthermore, the crystal structure of SjTrx in the oxidized state was determined at 2·0 Å resolution, revealing a typical architecture of thioredoxin fold. The structural information of SjTrx provides us important clues for understanding the maintenance function of redox homeostasis in S. japonicum and pathogenesis of this chronic disease.
It is well established that estrogen and progesterone are critical endogenous hormones that are essential for implantation and pregnancy in females. However, the distribution of estrogen receptor α (ERα) and progesterone receptor (PR) in female reproductive tracts is elusive. Herein, we report that after serial treatments with pregnant mare's serum gonadotrophin (PMSG) with or without anti-PMSG (AP), mice could regulate the distribution of ERα and PR in the murine ovary, oviduct and uterus and the level of estradiol in serum. ERα and PR regulation by PMSG and anti-PMSG was estrous cycle-dependent and critical for promoting the embryo-implantation period. Furthermore, our results suggested that AP-42 h treatment is more effective than the other treatments. In contrast, other treatment groups also affected the distribution of ERα and PR in mouse reproductive tracts. Thus, we found that anti-PMSG has the potential to restore the distribution of ERα and PR, which could effectively reduce the negative impact of residual estrogen caused by the normal superovulation effect of PMSG in mice.
Light propagation in a coupled system of Tamm plasmon-polariton and nonlinear cavity mode is theoretically investigated through the nonlinear transfer matrix method. It is found that the asymmetric layered structure exhibits both pronounced unidirectionality and high transmission. This leads to all-optical diode actions. Compared with other similar studies, the designed structure is much simple only with seven periods. The unique feature is that the direction of on-off can be reversed depending on the working frequencies. The effect of metal loss is also considered in this study.
The present study investigated the effects of xanthophyll supplementation on production performance, antioxidant capacity (measured by glutathione peroxidase, superoxide dismutase (SOD), catalase, total antioxidant capacity (T-AOC), and reduced glutathione:oxidised glutathione ratio (GSH:GSSG)) and lipid peroxidation (measured by malondialdehyde (MDA)) in breeding hens and chicks. In Expt 1, 432 hens were fed diets supplemented with 0 (control group), 20 or 40 mg xanthophyll/kg diet. Blood samples were taken at 7, 14, 21, 28 and 35 d of the trial. Liver and jejunal mucosa were sampled at 35 d. Both xanthophyll groups improved serum SOD at 21 and 28 d, serum T-AOC at 21 d and liver T-AOC, and serum GSH:GSSG at 21, 28 and 35 d and liver GSH:GSSG. Xanthophylls also decreased serum MDA at 21 d in hens. Expt 2 was a 2 × 2 factorial design. Male chicks hatched from 0 or 40 mg in ovo xanthophyll/kg diet of hens were fed a diet containing either 0 or 40 mg xanthophyll/kg diet. Liver samples were collected at 0, 7, 14 and 21 d after hatching. Blood samples were also collected at 21 d. In ovo-deposited xanthophylls increased antioxidant capacity and decreased MDA in the liver mainly within 1 week after hatching. Maternal effects gradually vanished during 1–2 weeks after hatching. Dietary xanthophylls increased antioxidant capacity and decreased MDA in the liver and serum mainly from 2 weeks onwards. Data suggested that xanthophyll supplementation enhanced antioxidant capacity and reduced lipid peroxidation in different tissues of hens and chicks.
Phenolic resin and tetraethoxysilane were used to prepare a binary carbonaceous silicon xerogel, the precursor of silicon carbide (SiC). By employing different additives in the sol-gel process, a series of xerogel precursors with differently chemical composition were obtained. Heating these xerogels to 1250°C, nanostructured β-SiC with various morphologies including nanowires, nanofibers, nanoparticles and mesoporous SiC were produced via carbothermal reduction. The preparation method of the xerogels was presented and the influences of different additives on the sol-gel process and the SiC formation were discussed in this paper.
The applicability of Nb as a Schottky barrier on GaAs depends to a large extent on the thermal stability of the contacts. In this study, bulk diffusion couple and phase diagram studies in addition to thin film studies were completed to understand the stability of and the reactions at the Nb/GaAs interface. Nb thin films were deposited onto GaAs substrates by dc magnetron sputtering and were annealed in the temperature range 300 to 1000°C. Analysis was done using plan-TEM and XTEM. The Nb/GaAs interface was found to break down into a series of binary compounds above 500°C. Bulk diffusion couples annealed at 600°C were analyzed using an electron microprobe. The stable sequence of phases formed in the couple, i.e., the diffusion path, was determined and was used to rationalize the observed compound formation in the thin film contact system.
High-capacity carbon electrodes for rechageable lithium-ion batteries were prepared by carbonization of thermosetting resins such as phenol-formaldehyde at temperatures between 500°C and 600°C. Their structures were characterized by high resolution transmission electron microscopy, in-situ transmission electron microscopy and x-ray diffraction analysis. These studies suggest that the carbons consist predominantly of disorganized (amorphous) phase. However evidence was found in carbon containing nickel cobalt oxide for the presence of organized graphite-like regions of parallel and curved layer planes. These graphitized structure usually appear as agglomerate particles which are composed of many smaller (100-nm diameter) particles. The high degree of graphitization is attributed to catalytic graphitization that occurs in the presence of the metal oxide.
Four new transit light curves of XO-2b obtained in 2008 and 2009, are analyzed by using MCMC algorithm, and the system parameters are derived. The result demonstrates that the orbital period of the system obtained from new observations is almost the same as Burke et al.'s one (2007), which does not confirm the result of Fernandez et al. (2009).
The potential relationship between the establishment of Foot-and-mouth disease virus (FMDV) persistent infection and gene variation was identified by investigating the variation of VP1 and 3ABC genes from yellow cattle persistent infection isolates. Five yellow cattle were inoculated on their tongue with 1.0×104 ID50/ml of FMDV O/Akesu/58 strain. After displaying clinical or subclinical signs, they probably became asymptomatic carriers. Oesophageal–pharyngeal fluids were collected monthly from the carriers with a probang and inoculated into a baby hamster kidney cell line (BHK-21); 12 FMDV isolates were obtained. The VP1 and 3ABC genes of the 12 isolates were then amplified by reverse-transcriptase polymerase chain reaction (RT-PCR). Cloning and sequencing revealed that the homology of the VP1 nucleotide and amino-acid sequence of all the isolates was above 98%, with no base deletion or insertion. When compared with the O/Akesu/58 FMDV strain, the homology of the VP1 nucleotide sequence of the isolates was only 85%, and that of the deduced amino-acid sequence only 90%.There were several nucleotide mutations in the VP1 gene of the isolates, including 16 consistent nucleotide mutations, with only two of them leading to a change in amino acid (I56→T, A210→E). Moreover, it was found that four nucleotide points and three amino-acid points had transversions among all isolates. The 3ABC gene had only 13 nucleotide transversions and five amino-acid mutations. It was presumed that persistent FMDV infection might have little connection with variation in the VP1 and 3ABC genes, and was probably related to other structural protein gene and key factors.
Twins could play a crucial role in our understanding of genetic contributions to numerous etiologically complex disorders. In China, although adult twins are relatively rare, twins will become increasingly available due to increasing twin birth rates. Thus, child twin data will be a valuable resource to contribute to the field of child and adolescent psychopathology. The first twin database of children aged from 6 to 16 was established in Chongqing, R.P., China. In this article, we will discuss our experiences in establishing the twin database, completed in three steps — the first step being to search and identify twins, the second being to keep contact with the twins and the final being to seek cooperation with the twin families, and its future prospects. Our twin database has proven to be an efficient method for the investigation and data collection of twin children in China. The results of our present study suggest that the inclusion of twin information in the residence registration of the public security bureaus in the future may ensure a smooth run of research based on the demographic resources. We propose that school networks may be adopted as the preferred method of collection of twin records for future studies.
Intergeneric transfer of plasmid vectors pSET152 and pHL212 from donor Escherichia coli ET12567/pUZ8002 and S17-1 to Streptomyces cinnamonensis was demonstrated and optimized. Assisted by this conjugation system, nsdA gene disruption was achieved through PCR-targeted gene replacement. One AprRKanS exconjugant BIB309 was then isolated and confirmed to be the nsdA null mutant. Compared with the starting strain, monensin production by the nsdA− mutant BIB309 increased 270% in vitro.
Three SuperWASP transiting planet candidates were observed through R or I filters using the 1-meter telescope and CCD camera of Yunnan Observatory from 2006 to 2007. The relative photometric data were corrected for the systematic errors by means of Tamuz et al. (2005) and Collier Cameron et al. (2006)'s algorithms. The resulting light curves demonstrate that one of three targets is a potential exoplanet candidate, which is worthy to perform further follow-up observation to clarify.
A new method of preparing carbon nanotubes and their derivatives using silica aerogels as a matrix for the deposition of carbon is repeated. We present results of observations of graphite tubes and rings including nested structures in nanometer dimensions using high resolution transmission electron microscopy. Furthermore, we propose a model for the growth of carbon nanotubes in three steps including nucleation, growth, and closure of tubes.
Although pseudocyst of the auricle is a common disease in China, its cause and mechanism are still not clear. Several methods of treatment have been advocated: repeated aspirations combined with physiotherapy, and incision and drainage with contour pressure dressing, magnetotherapy etc. In recent years, a new technique with a drainage tube inserted into the pseudocyst using a guide needle has been used in our hospital in the treatment of this condition. We report 45 cases treated by this method, none of whom had the condition previously.
Solid-state reactions between niobium and gallium arsenide in both thin film and bulk forms were studied in the temperature range 400 to 1000 °C using transmission electron microscopy (TEM), metallography, scanning electron microscopy (SEM), and electron probe microanalysis (EPMA). Initially Nb4As3 and Nb5Ga3 formed at the interface and grew very slowly. Following an incubation period, NbAs and NbGa, nucleated and grew at rates several orders of magnitude faster than the initial phases. The resulting metastable diffusion path, Nb/NbGa3/NbAs/GaAs, was observed even after relatively long-term annealing and is believed to be kinetically stabilized. Formation of the other Nb–Ga binary compounds as predicted by the phase diagram was inhibited by nucleation and kinetic barriers. The observed reaction sequence is discussed considering the thermodynamics, kinetics, and possible growth mechanisms involved in the reaction.
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