Tenascin is an extracellular matrix glycoprotein known to be an essential factor for the modulation of reciprocal interactions between the epithelium and mesenchyme during embryogenesis and tumourigenesis. The interactions between the expression of tenascin in the liver of Syrian golden hamster and the development of bile duct cancer in an Opisthorchis viverrini-associated cholangiocarcinoma model were investigated. The tenascin was expressed in connective tissues surrounding the dilated ducts, ductal rims and the stroma of cancers, and strongly in the stroma flame of necrotic cancer nodules. The mRNA signal for tenascin was also recognized in the stroma cells. The potential roles of tenascin as prognostic tumour markers are discussed.

The nucleotide sequences of partial 18S, complete internal transcribed spacer region 1 (ITS1), complete 5.8S, complete ITS2 and partial 28S of ribosomal DNA (rDNA) and cytochrome c oxidase subunit 1 of mitochondrial DNA (MCOI) from five species of gnathostomes (G. spinigerum, G. doloresi, G. nipponicum, G. hispidum and G. binucleatum with the former four species being distributed in Japan and Asia) that cause human gnathostomiasis were compared by direct polymerase chain reaction cycle-sequencing. The nucleotide sequences of each region of the18S (613 bp), 5.8S (158 bp) and 28S (598 bp) rDNA from the five species were almost identical. The ITS1 region was different in length for the five species. The nucleotide sequences of each region of ITS2 and partial MCO1 regions were different among the five species. Therefore, these two regions can be used as genetic markers for identification of worms.

In the present study, a compressible low-Reynolds-number flow over a circular cylinder was investigated using a low-density wind tunnel with time-resolved schlieren visualizations and pressure and force measurements. The Reynolds number ($Re$) based on freestream quantities and the diameter of a circular cylinder was set to be between 1000 and 5000, and the freestream Mach number ($M$) between 0.1 and 0.5. As a result, we have clarified the effect of $M$ on the aerodynamic characteristics of flow over a circular cylinder at $Re=O(10^{3})$. The results of the schlieren visualization showed that the trend of $M$ effect on the flow field, that are the release location of the Kármán vortices, the Strouhal number of vortex shedding and the maximum width of the recirculation, is changed at approximately $Re=3000$. In addition, the spanwise phase difference of the surface pressure fluctuation was captured by the measurement using pressure-sensitive paint at approximately $Re=3000$ of higher-$M$ cases. The observed spanwise phase difference is considered to relate to the spanwise phase difference of the vortex shedding due to the oblique instability wave on the separated shear layer caused by the compressibility effects. The Strouhal number of the vortex shedding is influenced by $M$ and $Re$, and those effects are nonlinear. However, the effects of $M$ and $Re$ can approximately be characterized by the maximum width of the recirculation. In addition, the $M$ effect on the drag coefficient can be characterized by the maximum width of the recirculation region and the Prandtl–Glauert transformation.

The Keio Twin Research Center (KoTReC) was established in 2009 at Keio University to combine two longitudinal cohort projects — the Keio Twin Study (KTS) for adolescence and adulthood and the Tokyo Twin Cohort Project (ToTCoP) for infancy and childhood. KoTReC also conducted a two-time panel study of self-control and psychopathology in twin adolescence in 2012 and 2013 and three independent anonymous cross-sectional twin surveys (ToTcross) before 2012 — the ToTCross, the Junior and Senior High School Survey and the High School Survey. This article introduces the recent research designs of KoTReC and its publications.

The number of tests performed is an important surveillance indicator. We illustrate this point using HIV surveillance data, focusing on Tokyo and Okinawa, two prefectures with high HIV notification rates in Japan. Restricting to data reported from local public health centres and affiliate centres where testing data are accessible, we assessed HIV surveillance data during 2007–2014, based on the annual HIV notification rate (per 100 000 population), HIV testing rate (per 100 000 population) and proportion testing HIV-positive (positivity). Nationally, testing activity and positivity showed an inverse relationship; in 2008, the testing rate peaked, but positivity was lowest. While notification rates were higher for Tokyo (median = 0.98, range = 0.89–1.33) than Okinawa (median = 0.61, range = 0.42–1.09), Okinawa had slightly higher testing rates (median = 187, range = 158–274) relative to Tokyo (median = 172, range = 163–210). Positivity was substantially lower in Okinawa (median = 0.34%, range = 0.24–0.45%) compared with Tokyo (median = 0.57%, range = 0.46–0.67%). Relative to the national testing rate (median = 85, range = 80–115) and positivity (median = 0.34%, range = 0.28–0.36%), Tokyo had higher positivity, despite more testing. In 2014 in Okinawa, all three indicators increased, providing a strong reason to be concerned as positivity increased despite more testing. Together with other information, accounting for testing and positivity improve interpretation of surveillance data to guide public health assessments.

Elemental behaviour, during the process of weathering of glazed sekishu roof-tiles affected by Lecidea s.lat. sp. (a crustose lichen), was investigated using optical and fluorescence microscopy, field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy. Sekishu roof tiles have an opaque reddish brown glaze on their surfaces which consist of an alkali feldspar-type X-ray amorphous glass recrystallized at 1200°C. Optical and fluorescence microscopy revealed the presence of corrosion pits (at a depth of ∼50 μm) at the lichen-glaze interface. Elemental mapping by FE-SEM identified the concentrations of Ti and Fe in the section of the glazed tile analysed. The behaviour of C was correlated with those elements, suggesting the possibility of biomineralization.

Agriculture and livestock production systems are two major emitters of greenhouse gases. Methane with a GWP (global warming potential) of 21, and nitrous oxide (N2O) with a GWP of 300, are largely emitted from animal production agriculture, where livestock production is based on pasture and feed grains. The principal biological processes involved in N2O emissions are nitrification and denitrification. Biological nitrification inhibition (BNI) is the natural ability of certain plant species to release nitrification inhibitors from their roots that suppress nitrifier activity, thus reducing soil nitrification and N2O emission. Recent methodological developments (e.g. bioluminescence assay to detect BNIs in plant root systems) have led to significant advances in our ability to quantify and characterize the BNI function. Synthesis and release of BNIs from plants is a highly regulated process triggered by the presence of NH4+ in the rhizosphere, which results in the inhibitor being released precisely where the majority of the soil-nitrifier population resides. Among the tropical pasture grasses, the BNI function is strongest (i.e. BNI capacity) in Brachiaria sp. Some feed-grain crops such as sorghum also have significant BNI capacity present in their root systems. The chemical identity of some of these BNIs has now been established, and their mode of inhibitory action on Nitrosomonas has been characterized. The ability of the BNI function in Brachiaria pastures to suppress N2O emissions and soil nitrification potential has been demonstrated; however, its potential role in controlling N2O emissions in agro-pastoral systems is under investigation. Here we present the current status of our understanding on how the BNI functions in Brachiaria pastures and feed-grain crops such as sorghum can be exploited both genetically and, from a production system's perspective, to develop low-nitrifying and low N2O-emitting production systems that would be economically profitable and ecologically sustainable.

The Keio Twin Research Center has conducted two longitudinal twin cohort projects and has collected three independent and anonymous twin data sets for studies of phenotypes related to psychological, socio-economic, and mental health factors. The Keio Twin Study has examined adolescent and adult cohorts, with a total of over 2,400 pairs of twins and their parents. DNA samples are available for approximately 600 of these twin pairs. The Tokyo Twin Cohort Project has followed a total of 1,600 twin pairs from infancy to early childhood. The large-scale cross-sectional twin study (CROSS) has collected data from over 4,000 twin pairs, from 3 to 26 years of age, and from two high school twin cohorts containing a total of 1,000 pairs of twins. These data sets of anonymous twin studies have mainly targeted academic performance, attitude, and social environment. The present article introduces the research designs and major findings of our center, such as genetic structures of cognitive abilities, personality traits, and academic performances, developmental effects of genes and environment on attitude, socio-cognitive ability and parenting, genes x environment interaction on attitude and conduct problem, and statistical methodological challenges and so on. We discuss the challenges in conducting twin research in Japan.

This study examined the link between sibling relationships and children's social adjustment by comparing twin siblings and siblings with different ages (singleton siblings), and clarified the role of reciprocity in sibling relationships on children's social development. Mothers of 58 monozygotic twin pairs, 48 dizygotic twin pairs, and 86 singleton sibling pairs reported their children's sibling relationships and social adjustment. This study showed that the effects of sibling relationships on the prosocial behaviors and conduct problems of each child are stronger for twins than for singleton siblings. Moreover, positivity toward one's sibling increased peer problems only among monozygotic twins. The opposite tendency was present among dizygotic twins and singleton siblings. This study suggests the importance for children's social development of having many interactions with siblings and establishing reciprocity in sibling relationships. Moreover, our results suggest that the quality of sibling relationships among monozygotic twins may be different from those among dizygotic twins and singleton siblings.

In three studies, a General Factor of Personality (GFP) was found to occupy the apex of the hierarchical structure. In Study 1, a GFP emerged independent of method variance and accounted for 54% of the reliable variance in a multitrait–multimethod assessment of 391 Italian high school students that used self-, teacher-, and parent-ratings on the Big Five Questionnaire — Children. In Study 2, a GFP was found in the seven dimensions of Cloninger's Temperament and Character Inventory as well as the Big Five of the NEO PI-R, with the GFPtci correlating r = .72 with the GFPneo. These results indicate that the GFP is practically the same in both test batteries, and its existence does not depend on being extracted using the Big Five model. The GFP accounted for 22% of the total variance in these trait measures, which were assessed in 651 pairs of 14- to 30-year-old Japanese twins. In Study 3, a GFP accounted for 32% of the total variance in nine scales derived from the NEO PI-R, the Humor Styles Questionnaire, and the Trait Emotional Intelligence Questionnaire assessed in 386 pairs of 18- to 74-year-old Canadian and U.S. twins. The GFP was found to be 50% heritable with high scores indicating openness, conscientiousness, sociability, agreeableness, emotional stability, good humor and emotional intelligence. The possible evolutionary origins of the GFP are discussed.

The Tokyo Twin Cohort Project (ToTCoP) is a large-scale longitudinal study of 5 years based on 1619 pairs of infant twins reared together. The purpose of the study is to construct a population-based twin registry in Japan and to investigate human growth and development and twin themselves. It covers behavioral, neurological, physical and environmental variables measured by questionnaire, home visiting and brain imaging technology. The full registry contains over 47,000 multiple births collected from the Basic Resident Register, and the targeted population is 3070 probable twins of 0 to 2 years old. Preliminary analysis of the entry questionnaire data showed no serious sampling biases. Descriptive statistics of parental characteristics (parental age, gestation age, parity and placentation, maternal weight, parenting stress) and children's characteristics (body size at birth, 4 and 10 months of age, milk consumption, and sleeping and social behavior) and their correlations, genetic and environmental contributions and correlations are reported.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Shock propagation through a bubbly liquid contained in a deformable tube is considered. Quasi-one-dimensional mixture-averaged flow equations that include fluid–structure interaction are formulated. The steady shock relations are derived and the nonlinear effect due to the gas-phase compressibility is examined. Experiments are conducted in which a free-falling steel projectile impacts the top of an air/water mixture in a polycarbonate tube, and stress waves in the tube material and pressure on the tube wall are measured. The experimental data indicate that the linear theory is incapable of properly predicting the propagation speeds of finite-amplitude waves in a mixture-filled tube; the shock theory is found to more accurately estimate the measured wave speeds.

The optical isolator made of diluted magnetic semiconductor and the isolator made of a ferromagnetic-metal/semiconductor hybrid have been developed aiming to integrate nonreciprocal optical devices, such as an optical isolator and optical circulator, into the semiconductor-made optoelectronic integrated circuits,. The Cd1-xMnxTe exhibits a huge Faraday effect and can be grown on a semiconductor substrate. For Cd1-xMnxTe waveguide with a Cd1-xZnxTe/ Cd1-xMnxTe quantum well grown on GaAs substrate we achieved a high Faraday rotation of 2000 deg/cm, a high isolation ratio of 27 dB, a low optical loss of 0.5 dB/cm, and a high magneto-optical figure-of-merit of 2000 deg/dB/kG in a wide 25-nm wavelength range. It was predicted theoretically and proved experimentally the effect of non-reciprocal loss in hybrid semiconductor/ferromagnetic metal waveguides. This effect can be use for new design of waveguide optical isolator. Because of its simplicity and technological compatibility, this design is attractive for the integration into optoelectronic integrated circuits. The magneto-optical figure-of merit of 7% was demonstrated for the AlGaAs passive optical waveguide covered by Co.

Cryptosporidium parvum, belonging to the phylum Apicomplexa, is a major cause of waterborne gastroenteritis throughout the world. The sporozoites are thought to invade host enterocytes using an active process termed gliding motility. However, the biological and morphological changes within the sporozoites during this process are not fully understood. In the present study, excysted sporozoites of C. parvum were analysed ultrastructurally in vitro and their viability was evaluated using fluorescent dyes. The sporozoites excysted from oocysts changed morphologically from banana-shaped to rod-shaped and finally to a rounded shape, in culture media in 3 h. Transmission microscopy revealed that the distance between the apical end and the nucleus was markedly reduced, dense granules were present close to the rhoptry in the apical region, amylopectin granules were absent, and membranes of round sporozoites were less clear. A fluorescent assay showed that the rate of survival decreased from 89% to 56% at 0–3 h (84·3% for banana-shaped and 49·2% for rod-shaped sporozoites). Therefore, post-excysted sporozoites in vitro underwent morphological changes and a rapid loss of viability. This staining method is useful, inexpensive and provides an alternative to more costly and intensive flow cytometric assays or infectivity assays with host cells in vitro.