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We used a bivariate animal model to investigate the genetic correlations between yield traits or days open (DO) as characters measured in cows and semen production traits as characters measured in bulls. Lactation records of 305-day milk, fat, and protein yields, and DO, from 386 809 first-lactation Holstein cows in Hokkaido, Japan, that calved between 2008 and 2014 were used. Semen production records were collected between 2005 and 2014 and included volume per ejaculate (VOL), sperm concentration (CON), number of sperm per ejaculate (NUM), progressive motility index of sperm (MOT), and MOT after freeze-thawing (A-MOT). Number of sperm per ejaculate was log-transformed into a NUM score (NUMS). A total of 30 373 semen production records from 1196 bulls were obtained. The pedigree file used for analysing the records was involving 885 345 animals. Heritability was estimated for VOL (0.42), CON (0.12), NUMS (0.37), MOT (0.08), and A-MOT (0.11). Weak and negative genetic correlations were recorded between yield traits measured in cows and VOL, CON or NUMS measured in bulls. Moderate and negative genetic correlations were obtained between DO and MOT (–0.42) or A-MOT (–0.43). Selection focused on MOT or A-MOT measured in bulls may therefore improve DO measured in cows.
Unavailability of irrigation water for early sowing has remained a constant problem in cold arid deserts of Ladakh. In order to get a solution to this problem, a 2-yr farmers’ participatory research trial with best bet agronomic management on artificial glacier water harvesting technology was conducted. The technology involves collecting water from natural glaciers that melt during late December. The water is diverted toward a shed constructed with stone embankments set up at regular intervals. The area is chosen where there is minimum interference of solar radiation, generally between two mountain slopes or ridge that is on the leeward side. The melted water is that melts from the natural glacier impeded by the embankments and get frozen here. This frozen water starts melting in late March and is used for both pre sowing and initial crop water requirement. It also ensures early sowing of wheat by creating additional 45-day window which leads to introduction of long- and medium-duration wheat varieties to replace decades old locally grown short-duration varieties. The work was initiated with a benchmark survey of 100 farmers to get an understanding of present irrigation scenario, crop management practices and date of sowing. Data from 99 farmer participating trial of wheat conducted after or from bench mark survey clearly indicated that the effect of water shortage can be seen on yield and yield attributing characters due to unavailability of pre sowing irrigation and water requirement at imperative growth stages and may also lead to terminal heat stress in wheat crop. Out of total number of irrigations applied, initial two irrigations can be compensated by artificial glacier water harvesting technique, leading to a revolution in the agriculture scenario of the tribal population by introduction of long- and medium-duration wheat varieties in cold arid desert of Ladakh for the very first time. It was observed that wheat seeding done in first fortnight of April gave better yields in comparison to late seeded wheat. Moreover, the long-duration varieties (LDVs) or medium-duration varieties (MDVs) sown under late condition gave better yield in comparison to locally grown short-duration varieties sown at same time. Yield potential of LDVs and MDVs of wheat under late sowing was found quite low in comparison to early-sown wheat, still when compared with the performance of locally grown wheat the yields were more even if the local varieties were sown early. The outcome of this study will help the farmers of tribal, cold arid community in harvesting better wheat yields by timely sowing of the wheat crop accompanied with better bet agronomic management practices. Government initiative is further required to ensure better outreach of complete crop management strategies to the tribal farming community of the region in order to ensure food security and improve their socioeconomic status.
We are currently conducting three kinds of IR surveys of star forming regions (SFRs) in order to seek for very low-mass young stellar populations. First is a deep JHKs-bands (simultaneous) survey with the SIRIUS camera on the IRSF 1.4m or the UH 2.2m telescopes. Second is a very deep JHKs survey with the CISCO IR camera on the Subaru 8.2m telescope. Third is a high resolution companion search around nearby YSOs with the CIAO adaptive optics coronagraph IR camera on the Subaru. In this contribution, we describe our SIRIUS camera and present preliminary results of the ongoing surveys with this new instrument.
Although presently classified as a SU UMa-type dwarf nova, WZ Sge is well known as one of the most peculiar objects in that it shows only superoutbursts with exceptional duration and amplitude, and no normal outbursts. Furthermore, on its decline from the 1978 outburst, WZ Sge showed a deep temporal dip. All of these characteristics have puzzled both theoreticians and observers.
The dwarf nova AL Com was photometrically observed during the outburst in 1995 April, which occurred for the first time since 1975. The striking similarity of AL Com to WZ Sge, as demonstrated by the present observation (Fig. 1), provides plenty of material in interpreting the enigmatic nature of WZ Sge-type dwarf novae.
A balloon observation of the F-corona in visual and infrared regions was carried out by Japanese and Indonesian teams at the total solar eclipse on June 11, 1983, in Java, Indonesia. For the visual observation, a SIT television camera, with 4 interference filters (5300Å, 6000Å, 7200Å and 8000Å) and a 45°-step rotating polarizer, was used. The camera measured brightness distributions in a sky area of 5°×5° centered at the eclipsed sun at each polarizer position for each filter. In this paper, a part of results, which are the brightness and polarization distributions in a half area of the 6000Å picture, is shown.
There is a gap in the distribution of the orbital periods of cataclysmic variables (CVs) between 2 and 3 hours. The period gap is explained at present by cessation of the mass transfer making CVs fainter and preventing them from being discovered. After restarting the mass transfer, CVs have been believed to evolve with the orbital periods becoming shorter, as angular momentum is released by gravitational wave radiation. In this view, the mass transfer rate depends almost only on the orbital period.
However, reconsideration of these views is urged by a series of recent discoveries of ER UMa stars (a subclass of SU UMa stars having enormous mass-transfer rates), dwarf novae bridging “classical” SU UMa stars and ER UMa stars, and the first in-the-gap dwarf nova, PG 1510+234. These objects suggest two possibilities; 1) (a part of) SU UMa stars undergo large secular changes of the mass-transfer rate, and 2) there exist parameters overlooked but strongly influential in the evolution of CVs.
A questionnaire was sent to all consenting doctors at the University of Ilorin Teaching Hospital, Nigeria. It asked about their management of psychological problems in their clinical practice. Over 90% would welcome more time to talk to patients and agreed that psychological and social factors should be routinely assessed and recorded for patients. Most respondents would refer patients with depression or disturbed behaviours. ‘Ineffective treatment’ and ‘dislike of psychiatric referral’ were not the main reasons for non-referral. A majority of the doctors had initiated treatment for anxiety and insomnia but not for alcohol withdrawal, psychosis, acute confusional state or depression. Doctors' awareness of ‘the impact of psychological factors on the course of physical illness' was high. To sustain this high level of awareness and encourage referral, in-house psychoeducational training of hospital doctors should be intensified. In addition, an increased doctor/patient ratio, public education to reduce stigma and a well developed liaison psychiatric service are imperative.
For the fabrication of bulk strained Si devices, a thin Si layer is deposited on a virtual substrate consisting of a several μm thick compositionally graded SiGe layer. A simpler approach utilizing H or He implantation to enhance relaxation of a thin SiGe film was recently reported. In this current work, hydrogen implantation is used to enhance the SiGe relaxation; and, relaxation beyond the previous reported limit is demonstrated. Experiments are performed on CVD deposited SiGe films with Ge fractions ranging from 20% to 40 % and thickness in the range of 100nm to about 500nm. After annealing at 800°C, relaxation of more than 80% is achieved. PMOS and NMOS devices are successfully fabricated and much enhanced hole and electron mobilities are demonstrated.
In order to achieve the widespread use of HIT (Hetero-junction with I etero-Intrinsic T ntrinsic Thin-layer) solar cells, it is important to reduce the power generating cost. There are three main approaches for reducing this cost: raising the conversion efficiency of the HIT cell, using a thinner wafer to reduce the wafer cost, and raising the open circuit voltage to obtain a better temperature coefficient. With the first approach, we have achieved the highest conversion efficiency values of 22.3%, confirmed by AIST, in a HIT solar cell. This cell has an open circuit voltage of 0.725 V, a short circuit current density of 38.9 mA/cm2 and a fill factor of 0.791, with a cell size of 100.5 cm2. The second approach is to use thinner Si wafers. The shortage of Si feedstock and the strong requirement of a lower sales price make it necessary for solar cell manufacturers to reduce their production cost. The wafer cost is an especially dominant factor in the production cost. In order to provide low-priced, high-quality solar cells, we are trying to use thinner wafers. We obtained a conversion efficiency of 21.4% (measured by Sanyo) for a HIT solar cell with a thickness of 85μm. Even better, there was absolutely no sagging in our HIT solar cell because of its symmetrical structure. The third approach is to raise the open circuit voltage. We obtained a remarkably higher Voc of 0.739 V with the thinner cell mentioned above because of its low surface recombination velocity. The high Voc results in good temperature properties, which allow it to generate a large amount of electricity at high temperatures.
We succeeded, for the first time, in depositing a silicon film which features 1000Å-wide single-crystalline grains embedded in a matrix of amorphous tissue. The deposition was done by plasma-enhanced CVD from silane diluted with hydrogen at a considerably high temperature (550°C). 5pm-thick undoped amorphous silicon film was deposited on the above film and was crystallized by a solid phase crystallization method. The polycrystalline silicon film which was obtained has a columnar structure and shows an extremely high electron mobility of 808 cm2/Vs.
The relationship between the grain size of poly-Si after SPC and the structure of a-Si before SPC was studied. The structure of a-Si was characterized by TA/TO: the Raman intensity ratio of the Transverse Acoustic (TA) like band and the Transverse Optical (TO) like band. A good positive correlation between the grain size and TS/TO was revealed for the first time. The nucleation and growth kinetics were speculated by using a thermodynamic model. The grain size could be enlarged up to 6 μ m by applying textured substrates to a-Si with a large structural disorder. This film was applied to the active layer of solar cells, and a collection efficiency of 51% at 900 nm was obtained.
Fracture process zone in SiCw/Si3N4 ceramic composite was studied by a hybrid experimental-numerical analysis employing moire interferometry and finite element analysis. A chevron-notched, wedge-loaded double cantilever beam specimen was used to obtain a stable crack growth. The relation between crack closure stress and crack opening displacement which govern fracture process zone was obtained.
The effects of specific local environments on DX centers were investigated for two different substitutional-site-donors of Si and Te in selectively-doped ordered-alloy samples. Capacitance transient technique under hydrostatic pressure was utilized for the determination of the DX energy-level structure. Downward movement of the energy levels for both Si- and Te-DX centers was observed when Al occupies the 2nd or 1st nearest neighbor site, respectively. A very large shift of the electron-emission activation-energy with pressure was found for the Te-DX centers surrounded by specific Al and Ga mixed-environments, whereas negligible shift for the Si-DX centers was observed regardless of the environment. These effects were discussed in relation to the lattice relaxation of the relevant DX centers.
High resolution transmission electron microscopy (HRTEM) of GaAs/AlAs hetero-structures grown by molecular beam epitaxy (MBE) is carried out in the <110> projection. It is shown that GaAs and AlAs are distinguished clearly by the difference in their lattice images at the samples thicknesses of about 15–30 nm under near Scherzer focus condition. Under these imaging conditions, very thin films consist of single monolayer AlAs are observed. Vicinal interfaces of GaAs/AlAs which were grown on (001) substrate misoriented toward  are also examined in the  projection. The interfacial structures are imaged edgeon, so that the fluctuations of terrace width, and the roughness of step-edges at these interfaces are observed on an atomic scale.
The electrical properties have been investigated on boron-doped polycrystalline silicon films with the average grain size of 50 nm and of 370 nm. It is shown that Hall mobility is strongly dependent on the grain size, and the temperature dependence is changed by hydrogenplasma treatment (HPT).
After the treatment in the larger grain film, the mobility of about 40 cm2/V sec is obtained and it shows the boron acceptor level of 0.043 eV, which is almost the same as that of the level in monocrystalline silicon. A kink in the mobility vs temperature curve which is observed in the smaller grain film disappears by HPT.
These phenomena will be discussed in relation to the density of the trapping states at the grain boundary of the films.
Sputtered thin-films of Gd-Bi (4:3 in atomic ratio) were annealed in vacuum under various annealing conditions. The samples annealed at a temperature near 530°C and 4 hours contained 40% of poly-crystalline Gd4Bi3 phase, which is of the anti-Th3P4 structure. The main peak in the x-ray diffraction spectrum due to Gd4Bi3 is of (310). The phase of Gd4Bi3 was not found for a lower annealing temperature; for a higher annealing temperature (above 550°C), this phase could not be observed, because other phases or structures were beginning to grow, e. g. Gd5Bi3 and/or GdBi phases.
The Curie temperature of the Gd4Bi3 thin-films was estimated to be about 330 K; this value is nearly the same as that of bulk Gd4Bi3. The residual resistance of the Gd4Bi3 thin-films was several times as large as that of bulk Gd4Bi3 poly-crystal.
Boron Nitride (BN) thin films are deposited on heated (650 °C ) silicon (100) substrates using Nd:YAG (532 nm) and KrF excimer (248 nm) laser ablation. The laser beam is focused on the hBN targets. The films are grown using a laser repetition rate of 10 Hz atenergy density 3.8 J/cm2. Argon gas is mixed with the reactant nitrogen gas and the total gas pressure in the chamber during deposition is 20 Pa. Auger Electron Spectroscopy shows that the N/B composition ratio depends on the mixture ratio of nitrogen and the relativeemission intensity of B + (345.1 nm). The surface morphology of the films prepared by the 532 nm laser is rough with large particulates, whereas much smoother surfaces with fewer and smaller particulates are obtained with the 248 nm laser. Fourier Transform IR measurement shows that the cBN phase in the films is enhanced by applying the negative RF self-bias voltage ( ˜ 200 V) on the substrate electrode.
In this report, we describe the fabrication and photo-induced alignment of ultrathin films of small molecular azobenzene dyes and polyelectrolytes using the alternate polyelectrolyte deposition (APD) technique. The molecular self-assembly process were investigated by QCM, ellipsometry, UV-vis spectroscopy, X-ray reflectometry, and other surface sensitive spectroscopic and microscopic methods to correlate with film formation parameters. The importance of layer ordering and dye aggregation phenomena is emphasized. We then utilized polarized UV-light to induce photo-alignment of these ultrathin films and observed high anisotropies dependent on the dye, layer preparation and thickness. Fabrication of hybrid LC cells using a nematic LC reveal that in-plane homogeneous alignment is influenced by the anisotropy of the dye aggregates.
We present work on the modification, processing, and analysis of ultrathin films for display devices primarily using the supramolecular assembly strategy. This involves the use of various molecular assembly techniques (organic, polymer, metal) in which layer order and functionality is achieved at defined length scales approaching that of ultrathin films (a few to several hundred nm thicknesses). The use of alternate polyelectrolyte deposition (APD) is primarily investigated in ultrathin films that have significance in the fabrication of display devices. The first application involves modifying a polymer light emitting diode (PLED) device fabricated using the ITO/MEH-PPV/Ca protocol with polyaniline derivatives. The second is the use of the “command layer” amplification concept and photo-induced alignment using polarized light with ultrathin films of azo dye/polyelectrolytes in a hybrid liquid crystal (LC) cell configuration. Both strategies rely on the use of surface sensitive spectroscopic and microscopic techniques to correlate device performance with layer ordering at the molecular level. The concept of functional ultrathin layers for device fabrication and modification is emphasized.
GaN films with good crystalline quality are grown on sapphire by atmospheric pressure vapor phase epitaxy using gallium tri-chloride (GaCl3) and ammonia (NH3). Epitaxial growth is carried out over temperature and V/III-ratio ranges of 800–1000°C and 100–1000, respectively. Typical growth rate obtained is in the range of 5–20 μm/hr. The films grown below 925°C typically show three dimensional (island) growth, while above that temperature, continuous films are obtained. Films grown at 975°C with a V/III ratio > 300 exhibit a smooth surface. XRD analysis shows that the films are single crystal with hexagonal polytype. Strong band-edge photoluminescence is observed with a FWHM of 60 meV at room temperature and 25 meV at 77K. The results indicate that this simple growth technique is effective for growing high quality bulk GaN, which can be used as a substrate for subsequent epitaxy. In order to further improve the surface morphology, a preliminary experiment on GaN growth on a thin GaN buffer layer prepared by gas source MBE is also presented.