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Obsessive compulsive disorder (OCD) is observed at increased rates in first-degree relatives of probands with autism spectrum disorders (ASDs). In addition, OCD-like traits are observed in autism, and in Asperger syndrome. Furthermore, subjects with OCD may have traits that overlap with some aspects of higher functioning ASDs. These observations suggest that OCD and ASDs may share some genetic risk factors. In support of this, it has recently been suggested that both common and rare functional variants in the serotonin transporter (SLC6A4) may increase risk for OCD and/or ASD. We will review our large-scale analysis of common and rare functional variants SLC6A4 in ASDs and relate these results to studies of OCD. In parallel studies, we have carried our linkage analysis in families with ASDs, focusing on those with more severe OCD-like traits. These families demonstrated increased evidence for linkage to chromosomes 1, 6, and 19. Evidence for linkage to chromosomes 6 and 19 have been observed in other studies, which we will summarize. Finally, we have examined the evidence that common variants in the NrCAM, TPH1 and TPH2 genes are associated with ASDs, particularly in patients with more severe OCD-like traits, and these results will be summarized.
Tourette syndrome (TS) is a neuropsychiatric disorder characterized by motor and vocal tics and associated complex behavioral abnormalities. There is strong support for a genetic basis to the disorder, however, the precise pattern of transmission and the identification of underlying genes has remained elusive. Recently, mutations in a gene termed SLIT- and NTRK-like family, member 1 (SLITRK1) have been shown to lead to rare forms of TS and associated disorders. The SLITRK family (SLITRK 1-6) includes neuronal transmembrane proteins that can control neurite outgrowth. Structurally, SLITRK family members are characterized by two leucine-rich repeat (LRR) domains located on the extracellular/intralumenal domain, a single transmembrane domain, and an intracellular/cytoplasmic domain that is of varying lengths. SLITRK1 has a cytoplasmic domain that is most different from the others, being both the shortest (53 amino acids), and lacking conserved potential sites of tyrosine phosphorylation. We are using molecular methods to dissect SLITRK1 signaling and metabolism.
Methods
We developed a bait from the human SLITRK1 protein and used it to screen libraries for SLITRK1-interacting proteins. In addition, we studied the metabolism of SLITRK1 in situ.
Results
We completed screens of both an adult and a fetal brain library and are characterizing the validated SLITRK1-interacting proteins. We have also characterized SLITRK1 metabolism and the effects of SLITRk1 mutations on its metabolism.
Conclusions
SLITRK1-interacting proteins may represent susceptibility loci for TS and related disorders, and are likely involved in the development of the central nervous system.
This study examines the relationship between paternal height or body mass index (BMI) and birth weight of their offspring in a Japanese general population. The sample included 33,448 pregnant Japanese women and used fixed data, including maternal, paternal and infant characteristics, from the Japan Environment and Children’s Study (JECS), an ongoing nationwide birth cohort study. Relationships between paternal height or BMI and infant birth weight [i.e., small for gestational age (SGA) and large for gestational age (LGA)] were examined using a multinomial logistic regression model. Since fetal programming may be a sex-specific process, male and female infants were analyzed separately. Multivariate analysis showed that the higher the paternal height, the higher the odds of LGA and the lower the odds of SGA in both male and female infants. The effects of paternal BMI on the odds of both SGA and LGA in male infants were similar to those of paternal height; however, paternal height had a stronger impact than BMI on the odds of male LGA. In addition, paternal BMI showed no association with the odds of SGA and only a weak association with the odds of LGA in female infants. This cohort study showed that paternal height was associated with birth weight of their offspring and had stronger effects than paternal BMI, suggesting that the impact of paternal height on infant birth weight could be explained by genetic factors. The sex-dependent effect of paternal BMI on infant birth weight may be due to epigenetic effects.
The near-infrared absorption line Fe I 15648 Å, which has a Landé g-factor of 3, shows a particularly large Zeeman splitting. We regularly take full-disk polarization maps of the Sun in the Fe I 15648 Å line (as well as the He I 10830 Å line) with an infrared spectropolarimeter installed at the Solar Flare Telescope of the National Astronomical Observatory of Japan (NAOJ). It is known that weak, mostly horizontal magnetic fields are ubiquitously distributed in the quiet regions of the Sun, while the strong magnetic fields are concentrated in active regions and network boundaries. The weak horizontal field has not been sufficiently investigated due to the difficulty of such observations. The polarization maps in Fe I 15648 Å show the magnetic field strength at each pixel, regardless of the filling factor, so we can easily isolate the weak horizontal field signals from strong magnetic field ones using the Stokes V profiles of the Fe I 15648 Å line. Here we present instrumental aspects and observational results of solar near-infrared full-disk polarimetry. We highlight the weak horizontal field inferred from Fe I 15648 Å.
(Na,K)NbO3 is a promising candidate for lead-free piezoelectric materials. (Na1-xKx)NbO3 films (x = 0.3–0.7) were epitaxially grown on a (100)SrTiO3 substrate via pulsed laser deposition. The effects of substrate temperature and oxygen pressure during deposition on the crystallinity of the films were examined: both parameters affected the mosaic spread of the crystallites and the formation of an impurity phase. In this study, the optimum conditions for the preparation of highly crystalline films were a substrate temperature of 800 °C and oxygen pressure of ∼60 Pa. The lattice constants parallel and perpendicular to the substrate surface responded differently to changes in x: the constant parallel to the surface increased with increasing x, while the constant perpendicular to the surface was maximized at x = 0.5. The difference in the dependence of the lattice constants could be explained by the elastic distortion of the lattice.
Native insects can become epidemic pests in agro-ecosystems. A population genetics approach was applied to analyze the emergence and spread of outbreak populations of native insect species. Outbreaks of the mirid bug, Stenotus rubrovittatus, have rapidly expanded over Japan within the last two decades. To characterize the outbreak dynamics of this species, the genetic structure of local populations was assessed using polymorphisms of the mtDNA COI gene and six microsatellite loci. Results of the population genetic analysis suggested that S. rubrovittatus populations throughout Japan were genetically isolated by geographic distance and separated into three genetic clusters occupying spatially segregated regions. Phylogeographic analysis indicated that the genetic structure of S. rubrovittatus reflected post-glacial colonization. Early outbreaks of S. rubrovittatus in the 1980s occurred independently of genetically isolated populations. The genetic structure of the populations did not fit the pattern of an outbreak expansion, and therefore the data did not support the hypothesis that extensive outbreaks were caused by the dispersal of specific pestiferous populations. Rather, the historical genetic structure prior to the outbreaks was maintained throughout the increase in abundance of the mirid bug. Our study indicated that changes in the agro-environment induced multiple outbreaks of native pest populations. This implies that, given suitable environmental conditions, local populations may have the potential to outbreak even without invasion of populations from other environmentally degraded areas.
In order to measure precisely the polarization of Crab Nebula and Cygnus X-1, we have been developing a hard X-ray polarimeter for balloon-borne experiments called PHENEX (Polarimetry of High ENErgy X-rays). It consists of several detectors called unit counters. The unit counter has a detection efficiency of 20% and a modulation factor of 53% at 80 keV. Up to now, we have finished the installation of eight unit counters to the polarimeter, that will be launched in Spring 2009 to observe the Crab Nebula. If the polarization of this source is more than 30%, the PHENEX polarimeter will be able to measure the degree and the direction of the polarization with errors less than 10% and 10°, respectively.
Introduction
X-ray astronomy has been much advanced by three observations: spectroscopy, timing, and imaging. Also in the hard X-ray region, these three observations will be realized by ASTRO-H and XEUS. However, the observation of the polarization is at the moment left out in spite of its potential usefulness. This is because of the difficulty of developing polarimeters with high sensitivity. Since the origin of the polarization is often due to nonthermal radiation processes such as synchrotron radiation, observations in the hard X-ray region are possibly more important than those in the soft X-ray region: it is expected that the degree of polarization in the hard X-ray region would be higher than that at lower energies.
We propose new measurement system for direct detection of WIMPs with directional information using nano imaging tracker (NIT) and X-ray microscope. The NIT made of fine grains of emulsion has a good spatial resolution of several tens nanometer and the X-ray microscope can work as a readout instrument for sub-micron track structure instead of ordinary optical microscope. Wolter type-I fluorescence X-ray microscope utilizing Ag-L line can be applied to this system. Crucial issues are reduction of background event due to random fog and to develop fast selection method of WIMP event candidates.
The accumulation and transmission of tomato spotted wilt virus (TSWV) was examined in second instar larvae and adults of two thrips genera, Frankliniella and Thrips. The species tested were F. occidentalis (Pergande), F. intonsa (Trybom), T. tabaciLindeman, T. setosus Moulton, T. palmi Karny and T. hawaiiensis (Morgan). In a standard petunia leaf disc assay, the efficiencies of TSWV transmission by two species of Frankliniella were higher than those of any Thrips species in the adult stage. A triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) showed that large amounts of the TSWV-nucleocapsid (N) protein were present in the ELISA-positive larvae of each species, with the exception of T. palmi. The ELISA titre of and the proportion of virus-infected individuals of the two Frankliniella species increased or did not significantly change from the larval to the adult stages, whereas those of the four Thrips species decreased significantly. These results show that the specificity of virus transmission by adult thrips is probably affected by the amount of viral N protein accumulation in the adults and that the accumulation pattern from the larval to the adult stages is in between the two genera tested in the present study.
The rapid crystallization of amorphous silicon utilizing a very-high-frequency (VHF) inductive coupling thermal microplasma jet of argon is demonstrated. Highly crystallized Si films were synthesized by adjusting the translational velocity of the substrate stage and flow rate of argon. The H concentration in the crystallized Si films decreased from 1021 cm−3 to 1019 cm−3 with no marked increases in oxygen and nitrogen impurity concentrations and defect density. The thin-film transistors of a 40-nm-thick crystallized a-Si film showed a field-effect mobility of 30–55 cm2/V s with a threshold voltage of 3–5 V. P-i-n thin-film solar cells were also fabricated for 1.5-μm-thick crystallized a-Si films, which showed an efficiency of 5.5% and filled factor of 0.52. The crystallization proceeded with time constants of $\sim $10 ms, which was of 4–6 orders of magnitude lower than the conventional laser-crystallization of a-Si. The crystallization process is discussed in terms of the viscous flow of Si-network, due to the rapid local heating and melting of a-Si.
Three-dimensional magnetohydrodynamics of the Solar coronal plasma is investigated by numerical simulation, aiming to understand the mechanisms of the Solar flare onset. It is demonstrated by the simulations that the resistive tearing mode instability growing on the magnetic shear inversion layer can drive the large-scale eruption through the mutual excitation of double reconnections. It is also revealed that the instability is able to cause the magnetohydrodynamic energy relaxation, in which the typical sigmoidal structure is self-organized prior to the onset of eruption. The simulation results predict that both the formation of sigmoids and the onset of flares should occur around the electric current sheet where the magnetic shear is steeply reversed. It is consistent with the reversed-shear flare model and the vector magnetograph observations.
From Yohkoh and SoHO observations, the magnetic reconnection is considered as a main energy release mechanism of the solar active phenomena. In this study, we try to reproduce GOES X-ray light curves (1–8 $\AA$) of solar flares using a model incorporating the radiative and conductive cooling and the magnetic reconnection heating.
Direct characterization of band alignment at chemical bath deposition (CBD)-CdS/Cu0.93 (In1-xGax)Se2 has been carried out by photoemission spectroscopy (PES) and inverse photoemission spectroscopy (IPES). Ar ion beam etching at the condition of the low ion kinetic energy of 350 eV yields a removal of surface contamination as well as successful measurement of the intrinsic properties of each layer and the interfaces. Especially interior regions of the wide gap CIGS layers with a band gap of 1.4 ∼ 1.6 eV were successfully exposed. IPES spectra revealed that the conduction band offset (CBO) at the interface region of the wide gap CIGS with x = 0.60 and 0.75 was negative, where the conduction band minimum of CdS was lower than that of CIGS. It was also observed that the energy spacing between conduction band minimum (CBM) of CdS layer and valence band maximum (VBM) of Cu0.93(In0.25Ga0.75)Se2 layer at interface region was no wider than that of the interface over the Cu0.93(In0.60Ga0.40)Se2 layer.
We report the result of a study of magnetic helicity in solar active regions during 1980-2000. Using the vector magnetograms from four instruments (Haleakala Stokes Polarimeter, Marshall Space Flight Center, Mitaka Solar Flare Telescope and Okayama Observatory Solar Telescope) we calculated the force-free parameter α and computed a slope dα/dφ as the linear fit of α vs. latitude φ, using annual subsets of data. The hemispheric helicity rule can be expressed in terms of this slope as dα/dφ < 0. We find that each instrument exhibits change in sign of dα/dφ for some years. However, we do not see consistency between different instruments in regards to years disobeying the rule. We show that this inconsistency can be attributed to insufficient numbers of active regions in annual subsets of data. We conclude that the present data sets do not allow to make statistically significant inference about possible cyclic variation of the hemispheric helicity rule.
For further discussion see Hagyard et al., 2003, ApJ, submitted.
A 2-dimensional Doppler coronagraph “NOGIS” (NOrikura Green-line Imaging System) at the Norikura Solar Observatory, NAOJ, is a unique imaging system that can provide both intensity and Doppler velocity of 2 MK plasma from the green coronal line emission $\lambda$5303 Å of Fe xiv. We present the first detection of a CME onset by NOGIS. The event was originally induced by a C9.1 confined flare that occurred on 2003 June 1 at an active region NOAA $\#$10365 near the limb. This flare triggered a filament eruption in AR 10365, which later evolved into a partial halo CME as well as an M6.5 flare at the same AR 10365 on 2003 June 2. The CME originated in a complex of two neighboring magnetic flux systems across the solar equator: AR 10365 and a bundle of face-on tall coronal loops. NOGIS observed i) a density enhancement in between the two flux systems in the early phase, ii) a blue-shifted bubble and jet that later appeared as (a part of) the CME, and iii) a red-shifted wave that triggered a periodic fluctuations in Doppler shifts in the face-on loops. These features are crucial to understand unsolved problems on a CME initiation (e.g., mass supply, magnetic configuration, and trigger mechanism) and on coronal loop oscillations (e.g., trigger and damping mechanisms). We stress a possibility that interaction between separatrices of the two flux systems played a key role on our event.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html
We analyse the role of Euler summation in a numerical inversion algorithm for Laplace transforms due to Abate and Whitt called the EULER algorithm. Euler summation is shown to accelerate convergence of a slowly converging truncated Fourier series; an explicit bound for the approximation error is derived that generalizes a result given by O'Cinneide. An enhanced inversion algorithm called EULER-GPS is developed using a new variant of Euler summation. The algorithm EULER-GPS makes it possible to accurately invert transforms of functions with discontinuities at arbitrary locations. The effectiveness of the algorithm is verified through numerical experiments. Besides numerical transform inversion, the enhanced algorithm is applicable to a wide range of other problems where the goal is to recover point values of a piecewise-smooth function from the Fourier series.
Relationships between leaf expansion and MeOH-soluble (cytosol) and cell-wall fractions, and their sugar composition prior to silking in flint corn lines were studied. A greater husk leaf area of one genotype, X-15 is mainly due to prolonged and higher rate of expansion. Prior to rapid expansion of husk leaf area, neutral sugars in the cytosol fraction accounted for most of the non-starch carbohydrates (56–62%), while hemicellulose and cellulose fractions accounted for less than 20%. In mature leaf parts, however, sugars in the cytosol fraction decreased but those in hemicellulose and cellulose fractions increased by 30% and 42%, respectively. The predominant sugar in the cytosol fraction was glucose (Glc), while in the hemicellulose fraction xylose (Xyl) and arabinose (Ara) dominated. During rapid expansion of husk leaves, 13C was incorporated at a higher rate into hemicellulose than cellulose, and this process was more active in X-15 than in other genotypes. During an identical period, 13C atom % excess in Xyl increased markedly in the hemicellulose fraction, however it remained low in the cytosol one. The current results suggest that synthesis of Xyl and xylan plays an important role in renewal of hemicellulose, which may be required for expansion.
Supposing coronal magnetic fields are in a force-free state from the chromosphere to the height of two solar radii, we reconstruct 3D force-free magnetic fields by making use of a new numerical technique, in which the fields are represented by a boundary integral equation based on a specific Green's function. Vector magnetic fields observed on the photospheric surface can be taken as the boundary conditions of this equation. Magnetic fields in AR8270 on 14 July 1998 were employed as an example to exhibit the capability of this numerical technique.