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We determine the asymptotic behavior of the higher dimensional Reidemeister torsion for the graph manifolds obtained by exceptional surgeries along twist knots. We show that all irreducible
-representations of the graph manifold are induced by irreducible metabelian representations of the twist knot group. We also give the set of the limits of the leading coeõcients in the higher dimensional Reidemeister torsion explicitly.
We initiated a long-term and highly frequent monitoring project toward 442 methanol masers at 6.7 GHz (Dec >−30 deg) using the Hitachi 32-m radio telescope in December 2012. The observations have been carried out daily, monitoring a spectrum of each source with intervals of 9–10 days. In September 2015, the number of the target sources and intervals were redesigned into 143 and 4–5 days, respectively. This monitoring provides us complete information on how many sources show periodic flux variations in high-mass star-forming regions, which have been detected in 20 sources with periods of 29.5–668 days so far (e.g., Goedhart et al. 2004). We have already obtained new detections of periodic flux variations in 31 methanol sources with periods of 22–409 days. These periodic flux variations must be a unique tool to investigate high-mass protostars themselves and their circumstellar structure on a very tiny spatial scale of 0.1–1 au.
Insufficient nutrition during the perinatal period causes structural alterations in humans and experimental animals, leading to increased vulnerability to diseases in later life. Japanese quail, Coturnix japonica, in which partial (8–10%) egg white was withdrawn (EwW) from eggs before incubation had lower birth weights than controls (CTs). EwW birds also had reduced hatching rates, smaller glomeruli and lower embryo weight. In EwW embryos, the surface condensate area containing mesenchymal cells was larger, suggesting that delayed but active nephrogenesis takes place. In mature EwW quail, the number of glomeruli in the cortical region (mm2) was significantly lower (CT 34.7±1.4, EwW 21.0±1.2); capillary loops showed focal ballooning, and mesangial areas were distinctly expanded. Immunoreactive cell junction proteins, N-cadherin and podocin, and slit diaphragms were clearly seen. With aging, the mesangial area and glomerular size continued to increase and were significantly larger in EwW quail, suggesting compensatory hypertrophy. Furthermore, apoptosis measured by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling analysis was higher in EwWs than in CTs on embryonic day 15 and postnatal day 4 (D4). Similarly, plasma glucocorticoid (corticosterone) was higher (P<0.01) on D4 in EwW quail. These results suggest that although nephrogenic activity is high in low-nutrition quail during the perinatal period, delayed development and increased apoptosis may result in a lower number of mature nephrons. Damaged or incompletely mature mesangium may trigger glomerular injury, leading in later life to nephrosclerosis. The present study shows that birds serve as a model for ‘fetal programming,’ which appears to have evolved phylogenetically early.
Public stigma alters attitudes towards people with mental illness, and is a particular concern for young people since most mental health problems occur in adolescence and young adulthood. However, little is known about the long-term effects of repeated filmed social contact (FSC) on reducing mental health-related stigma among young adults in the general population, compared with self-instructional Internet search (INS) and control interventions.
This study is a parallel-group randomised controlled trial over 12 months conducted in Tokyo, Japan. A total of 259 university students (male n = 150, mean age = 20.0 years, s.d. = 1.2) were recruited from 20 colleges and universities between November 2013 and July 2014, without being provided information about the mental health-related survey or trial. Participants were assigned to one of three groups before completion of the baseline survey (FSC/INS/control = 89/83/87). The FSC group received a computer-based 30-min social contact film with general mental health education and five follow-up web-based FSCs at 2-month intervals. The INS group undertook a 30-min search for mental health-related information with five follow-up web-based reminders for self-instructional searches at 2-month intervals. The control group played PC games and had no follow-up intervention. The main outcome measures were the future (intended behaviour) domain of the Reported and Intended Behaviour Scale at 12 months after the intervention. Analysis was conducted in September 2015.
At the 12-month follow-up, 218 participants completed the survey (84.1%, 75:70:73). The FSC group showed the greatest change at the 12-month follow-up (FSC: mean change 2.11 [95% CI 1.49, 2.73], INS: 1.04 [0.29, 1.80], control: 0.71 [0.09, 1.33]; FSC v. INS p = 0.037, FSC v. controls p = 0.004). No adverse events were reported during the follow-up period.
FSC was more successful in reducing stigma at 12 months after intervention than INS or control interventions. FSC could be used to reduce stigma in educational lectures and anti-stigma campaigns targeted at young people.
This study is registered at UMIN-CTR (No. UMIN000012239).
Pregnancy and calving are elements indispensable for dairy production, but the daily milk yield of cows decline as pregnancy progresses, especially during the late stages. Therefore, the effect of stage of pregnancy on daily milk yield must be clarified to accurately estimate the breeding values and lifetime productivity of cows. To improve the genetic evaluation model for daily milk yield and determine the effect of the timing of pregnancy on productivity, we used a test-day model to assess the effects of stage of pregnancy on variance component estimates, daily milk yields and 305-day milk yield during the first three lactations of Holstein cows. Data were 10 646 333 test-day records for the first lactation; 8 222 661 records for the second; and 5 513 039 records for the third. The data were analyzed within each lactation by using three single-trait random regression animal models: one model that did not account for the stage of pregnancy effect and two models that did. The effect of stage of pregnancy on test-day milk yield was included in the model by applying a regression on days pregnant or fitting a separate lactation curve for each days open (days from calving to pregnancy) class (eight levels). Stage of pregnancy did not affect the heritability estimates of daily milk yield, although the additive genetic and permanent environmental variances in late lactation were decreased by accounting for the stage of pregnancy effect. The effects of days pregnant on daily milk yield during late lactation were larger in the second and third lactations than in the first lactation. The rates of reduction of the 305-day milk yield of cows that conceived fewer than 90 days after the second or third calving were significantly (P<0.05) greater than that after the first calving. Therefore, we conclude that differences between the negative effects of early pregnancy in the first, compared with later, lactations should be included when determining the optimal number of days open to maximize lifetime productivity in dairy cows.
We present a numerical analysis of the rheology of a dense suspension of spherical capsules in simple shear flow in the Stokes flow regime. The behaviour of neo-Hookean capsules is simulated for a volume fraction up to
by graphics processing unit computing based on the boundary element method with a multipole expansion. To describe the specific viscosity using a polynomial equation of the volume fraction, the coefficients of the equation are calculated by least-squares fitting. The results suggest that the effect of higher-order terms is much smaller for capsule suspensions than rigid sphere suspensions; for example,
terms account for only 8 % of the specific viscosity even at
for capillary numbers
. We also investigate the relationship between the deformation and orientation of the capsules and the suspension rheology. When the volume fraction increases, the deformation of the capsules increases while the orientation angle of the capsules with respect to the flow direction decreases. Therefore, both the specific viscosity and the normal stress difference increase with volume fraction due to the increased deformation, whereas the decreased orientation angle suppresses the specific viscosity, but amplifies the normal stress difference.
We have conducted 1.1 mm ALMA observations of a contiguous 105” × 50” or 1.5 arcmin2 window in the SXDF-UDS-CANDELS. We achieved a 5σ sensitivity of 0.28 mJy, giving a flat sensus of dusty star-forming galaxies with LIR ~6×1011L⊙ (if Tdust=40K) up to z ~ 10 thanks to the negative K-correction at this wavelength. We detected 5 brightest sources (S/N>6) and 18 low-significant sources (5>S/N>4; they may contain spurious detections, though). One of the 5 brightest ALMA sources (S1.1mm = 0.84 ± 0.09 mJy) is extremely faint in the WFC3 and VLT/HAWK-I images, demonstrating that a contiguous ALMA imaging survey uncovers a faint dust-obscured population invisible in the deep optical/near-infrared surveys. We find a possible [CII]-line emitter at z=5.955 or a low-z CO emitting galaxy within the field, allowing us to constrain the [CII] and/or CO luminosity functions across the history of the universe.
Molybdenum disulfide (MoS2), one of the transition-metal dichalcogenides, is a 2-dimensional semiconducting material that has a layered structure. Owing to excellent optical and electronic properties, the ultra-thin MoS2 film is expected to be used for various devices, such as transistors and flexible displays. In this study, we investigated the physical and chemical properties of sputtered-MoS2 film in the sub-10-nm region by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). As the results of Raman spectroscopy investigations, we observed two Raman modes, E12g and A1g, in the 2-dimensional MoS2 films. As the thickness of the MoS2 film decreased, the peak frequency difference between E12g and A1g modes increased. From the XPS investigations, we confirmed sulfur reductions from the 2-dimensional MoS2 films. Therefore, we considered that the sulfur vacancies in the MoS2 film affected the Raman peak positions. Moreover, we performed the additional sulfurization of sputtered-MoS2 films. From the XPS and Raman investigations, the quality of the sputtered-MoS2 films was improved by the additional sulfurization.
The deformation of a spherical capsule in oscillating shear flow is presented. The boundary element method is used to simulate the capsule motion under Stokes flow. We show that a capsule at high frequencies follows the deformation given by a leading-order prediction, which is derived from an assumption of small deformation limit. At low frequencies, on the other hand, a capsule shows an overshoot phenomenon where the maximum deformation is larger than that in steady shear flow. A larger overshoot is observed for larger capillary number or viscosity ratio. Using the maximum deformation in start-up shear flow, we evaluate the upper limit of deformation in oscillating shear flow. We also show that the overshoot phenomenon may appear when the quasi-steady orientation angle under steady shear flow is less than
. We propose an equation to estimate the threshold frequency between the low-frequency range, where the capsule may have an overshoot, and the high-frequency range, where the deformation is given by the leading-order prediction. The equation only includes the viscosity ratio and the Taylor parameter under simple shear flow, so it can be extended to other deformable particles, such as bubbles and drops.
III-V compound multi-junction solar cells have high efficiency potential of more than 50% due to wide photo response, while limiting efficiencies of single-junction solar cells are 31-32%. In order to realize high efficiency III-V compound multi-junction solar cells, understanding and controlling imperfections (defects) are very important. This paper reviews fundamentals of defects and defect management for III-V compound materials, single-junction, multi-junction, space and concentrator solar cells.
Cu2ZnSnSe4 thin films were prepared by using the synthesized Cu2ZnSnSe4 ingot and Na2Se powder at various Na2Se/Cu2ZnSnSe4 mole ratio as evaporation materials for selenization process. From EPMA analysis, the composition was approximately constant even if the Na2Se/Cu2ZnSnSe4 mole ratio increased. X-ray diffraction studies revealed that the thin films had a kesterite Cu2ZnSnSe4 structure and the foreign phases disappeared with increasing the Na2Se/Cu2ZnSnSe4 mole ratio. The Na2Se addition enhanced to grow thin films having a close-packed structure and columnar grains. The values of Voc and Isc in Cu2ZnSnSe4 thin film solar cells increased with increasing the Na2Se/Cu2ZnSnSe4 mole ratio.
The effects of N2O gas addition on the properties of zinc oxide films grown on a-plane (11-20) sapphire (a-Al2O3) substrates were investigated, using a chemical vapor deposition method based on the reaction between dimethylzinc and high-energy H2O produced by a Pt-catalyzed H2-O2 reaction. By employing an optimal N2O gas pressure, both the film crystallinity and crystal orientation were improved. Subsequent to treatment with N2O, the electron mobility of films at room temperature increased from 207 to 234 cm2/Vs while the electron concentration decreased at low temperatures. In addition, the photoluminescence peak intensity of the nearband-edge emission was increased.
The aim of this study was to estimate genetic correlations between milk yield, somatic cell score (SCS), mastitis, and claw and leg disorders (CLDs) during first lactation in Holstein cows by using a threshold–linear random regression test-day model. We used daily records of milk, fat and protein yields; somatic cell count (SCC); and mastitis and CLD incidences from 46 771 first-lactation Holstein cows in Hokkaido, Japan, that calved between 2000 and 2009. A threshold animal model for binary records (mastitis and CLDs) and linear animal model for yield traits were applied in our multiple trait analysis. For both liabilities and yield traits, additive genetic effects were used as random regression on cubic Legendre polynomials of days on milk. The highest positive genetic correlations between yields and disease incidences (0.36 for milk and mastitis, 0.56 for fat and mastitis, 0.24 for protein and mastitis, 0.32 for milk and CLD, 0.44 for fat and CLD and 0.31 for protein and CLD) were estimated at about the time of peak milk yield (36 to 65 days in milk). Selection focused on early lactation yield may therefore increase the risk of mastitis and CLDs. The positive genetic correlations of SCS with mastitis or CLD incidence imply that selection to reduce SCS in the early stages of lactation would decrease the incidence of both mastitis and CLD.
We studied the diffusive transport of Cs, Np, Am and Co in compacted sandbentonite mixtures by using the through-diffusion method. The experiments for Cs were performed under various aqueous compositions. Effective diffusivity (De) values of 4.7×10–10 to 5.9×10–9 m2 s–1 were obtained with a somewhat large variation. Apparent diffusivity (Da) values, on the other hand, showed less variation, ranging from 2.0×10–12 to 6.2×10–12 m2 s–1. The results indicated that diffusive flux was proportional to the concentration gradient on the basis of the amount of Cs in the unit volume of the compacted sand-bentonite mixtures rather than the Cs concentration gradient in pore water. Because the former concentration gradient in the mixtures was nearly equal to that of adsorbed Cs, the diffusion of Cs in the mixtures was probably dominated by the concentration gradient of the Cs adsorbed on the mixtures. In addition, the effective/apparent diffusivity of 237Np(IV) and apparent diffusivity of 241Am(III) and 60Co(II) in the mixtures were determined in 0.3/0.03 mol l–1 (NH4)2CO3/Na2S2O4 solution.
Highly alkaline environments induced by cement-based materials are likely to cause the physical and/or chemical properties of the bentonite buffer materials in radioactive waste repositories to deteriorate. Assessing long-term alteration of concrete/clay systems requires physicochemical models and a number of input parameters. In order to provide reliability in the assessment of the long-term performance of bentonite buffers under disposal conditions, it is necessary to develop and verify reactive transport codes for concrete/clay systems. In this study, a PHREEQC-based, reactive transport analysis code (MC-CEMENT ver. 2) was developed and was verified by comparing results of the calculations with in situ observations of the mineralogical evolution at the concrete/argillite interface. The calculation reproduced the observations such as the mineralogical changes in the argillite limited to within 1 cm in thickness from the interface, formation of CaCO3 and CSH, dissolution of quartz, decrease of porosity in the argillite and an increase in the concrete. These agreements indicate a possibility that models based on lab-scale (∼1 year) experiments can be applied to longer time scales although confidence in the models is necessary for much longer timescales. The fact that the calculations did not reproduce the dissolution of clays and the formation of gypsum indicates that there is still room for improvement in our model.
Highly alkaline environments induced by cementitious materials in radioactive waste repositories are likely to alter montmorillonite, the main constituent of bentonite buffer materials, and are likely to cause the physical and/or chemical properties of the buffer materials to deteriorate. The deterioration may cause variation in hydraulic conductivity of the buffer. However, empirical data on the variation of hydraulic conductivity are scarce, mainly because the alteration of compacted buffer materials, sand-bentonite mixtures, is extremely slow. In this study, laboratory experiments were performed to observe changes in hydraulic conductivity of sand-bentonite mixtures, accompanied by their alkaline alteration, using NaOH-based solutions at 80–90°C. Series-1 multi-step alteration/water conduction experiments resulted in an increase in the hydraulic conductivity by one order of magnitude over a 200 day period. Series-2 single step alteration/water conduction experiments revealed a decrease in the montmorillonite contents with time and a resulting increase in the hydraulic conductivity by 30 times over the 67 day period. Series-3 simultaneous alteration/water conduction experiment also demonstrated an increase in the hydraulic conductivity by 30 times over the 150 day period. The results proved that the alkaline alteration of the bentonite buffer can increase the hydraulic conductivity. The data obtained in this study are useful for verification of the code that will be used for assessing the alteration.
In order to evaluate the long-term behaviour of the engineered barriers in geological disposal sites for transuranic element-bearing (TRU) waste, an evaluation by numerical analysis is required. Although chemical and hydraulic/mechanical analyses have been conducted independently until now, essentially both type of phenomena occur simultaneously and produce synergistic effects. Therefore, we focused attention on the buffer (bentonite) engineered barrier and conducted a study of which involved incorporating hydraulic/mechanical phenomena into the chemical analysis of bentonite alteration. The simulations employed weakly-coupled chemical and hydraulic/mechanical effects to study the behaviour in one dimension.
The results showed that the dissolution of the montmorillonite is suppressed in the buffer section nearest the cement material. Moreover, in order to achieve a fully coupled analysis in future, the present study also identifies issues that need to be resolved.
The diffusion of red blood cells (RBCs) in blood is important to the physiology and pathology of the cardiovascular system. In this study, we investigate flow-induced diffusion of RBCs in a semi-dilute system by calculating the pairwise interactions between RBCs in simple shear flow. A capsule with a hyperelastic membrane was used to model an RBC. Its deformation was resolved using the finite element method, whereas fluid motion inside and outside the RBC was solved using the boundary element method. The results show that shear-induced RBC diffusion is significantly anisotropic, i.e. the velocity gradient direction component is larger than the vorticity direction. We also found that the motion of RBCs during the interaction is strongly dependent on the viscosity ratio of the internal to external fluid, and the diffusivity decreases monotonically as the viscosity ratio increases. The scaling argument also suggests that the diffusivity is proportional to the shear rate and haematocrit, if the suspension is in a semi-dilute environment and the capillary number is invariant. These fundamental findings are useful to understand transport phenomena in blood flow.