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The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Observationally locating the position of the H2O snowline in protoplanetary disks is crucial for understanding planetesimal and planet formation processes, and the origin of water on the Earth. In our studies, we conducted calculations of chemical reactions and water line profiles in protoplanetary disks, and identified that ortho/para-H216O, H218O lines with small Einstein A coefficients and relatively high upper state energies are dominated by emission from the hot midplane region inside the H2O snowline. Therefore, through analyzing their line profiles the position of the H2O snowline can be located. Moreover, because the number density of the H218O is much smaller than that of H216O, the H218O lines can trace deeper into the disk and thus they are potentially better probes of the exact position of the H2O snowline in disk midplane.
Recently, many superflares on solar-type stars were discovered as white-light flares (WLFs). A correlation between the energies (E) and durations (t) of superflares is derived as t∝E0.39, and this can be theoretically explained by magnetic reconnection (t∝E1/3). In this study, we carried out a statistical research on 50 solar WLFs with SDO/HMI to examine the t-E relation. As a result, the t-E relation on solar WLFs (t∝E0.38) is quite similar stellar superflares, but the durations of stellar superflares are much shorter than those extrapolated from solar WLFs. We present the following two interpretations; (1) in solar flares, the cooling timescale of WL emission may be longer than the reconnection one, and the decay time can be determined by the cooling timescale; (2) the distribution can be understood by applying a scaling law t∝E1/3B−5/3 derived from the magnetic reconnection theory.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
We report the results of abundance analysis for high-resolution spectra of eight extremely metal-poor turn-off stars selected from SDSS/SEGUE. Based on differential analysis adopting stellar parameters from Balmer line profiles, we obtain the following results: i) Statistically significant scatter is found in [X/Fe] (X=Na, Mg, Cr, Ti, Sr and Ba), among which [Na/Fe] shows an apparent bimodal distribution, ii) Li abundances are ~0.3 dex lower in [Fe/H]<−3.5 than the Spite plateau value without significant scatter.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
We evaluate the synchrotron spectrum of Mrk 501 based on our filamentary jet model. Integrating the contribution from the magnetic fields induced by numerous current filaments with various transverse sizes, we reproduce the observed hardening of the spectrum around X-rays. It is found that the spectral change during 1997-1998 can be explained by the evolution of turbulence. We also propose that the observed dip around 80 keV is attributed to bound-free absorption by Fe atoms, which implies the abundance of heavy nuclei at the tip of the jet.
We carried out an extensive photometric and spectroscopic investigation of the SPB binary, HD 25558 (see Fig. 1 for the time and geographic distribution of the observations). The ~2000 spectra obtained at 13 observatories during 5 observing seasons, the ground-based multi-colour light curves and the photometric data from the MOST satellite revealed that this object is a double-lined spectroscopic binary with a very long orbital period of about 9 years. We determined the physical parameters of the components, and have found that both lie within the SPB instability strip. Accordingly, both components show line-profile variations consistent with stellar pulsations. Altogether, 11 independent frequencies and one harmonic frequency were identified in the data. The observational data do not allow the inference of a reliable orbital solution, thus, disentangling cannot be performed on the spectra. Since the lines of the two components are never completely separated, the analysis is very complicated. Nevertheless, pixel-by-pixel variability analysis of the cross-correlated line profiles was successful, and we were able to attribute all the frequencies to the primary or secondary component. Spectroscopic and photometric mode-identification was also performed for several of these frequencies of both binary components. The spectroscopic mode-identification results suggest that the inclination and rotation of the two components are rather different. While the primary is a slow rotator with ~6 d rotation period, seen at ~60° inclination, the secondary rotates fast with ~1.2 d rotation period, and is seen at ~20° inclination. Our spectropolarimetric measurements revealed that the secondary component has a magnetic field with at least a few hundred Gauss strength, while no magnetic field was detected in the primary.
The detailed analysis and results of this study will be published elsewhere.
Delirium and dementia are highly interrelated. However, few comprehensive epidemiological studies have examined this altered state of consciousness superimposed on dementia. We investigated the frequency of delirium in patients with dementia, its prevalence in patients with each dementia type, and its association with cerebrovascular disease (CVD) in patients with neurodegenerative dementias.
We studied 261 consecutive outpatients in the memory clinic of a psychiatric hospital between April 2010 and September 2011. All patients underwent routine laboratory tests and computed tomography (CT), and their Mini-Mental State Examination, Neuropsychiatric Inventory (NPI), Physical Self-Maintenance Scale (PSMS), and Delirium Rating Scale – Revised 98 scores were recorded. The diagnosis of delirium was based on the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision. CVD was detected by CT.
Among the 206 patients with dementia, delirium was present in 40 (19.4%). The proportion of patients who experienced episodes of delirium was 14.7% in the Alzheimer's disease, 34.4% in the vascular dementia, 31.8% in the dementia with Lewy bodies, and none in frontotemporal lobar degeneration. Delirium was frequently observed in patients with dementia and CVD. The NPI total and agitation subscale scores were significantly higher in dementia patients with delirium than in those without delirium. PSMS scores were significantly lower for patients with delirium than for patients without delirium.
The frequency of delirium varies with each dementia type. In addition, delirium decreases activities of daily living, exaggerates behavioral and psychological symptoms dementia, and is associated with CVD in patients with neurodegenerative dementias.
We have prepared 2% Al doped ZnO (AZO) thin films on SrTiO3 and Al2O3 substrates by Pulsed Laser Deposition (PLD) technique at various deposition temperatures (Tdep = 300 °C – 600 °C). Transport and thermoelectric properties of AZO thin films were studied in low temperature range (300 K - 600 K). AZO/STO films present superior performance respect to AZO/Al2O3 films deposited at the same temperature, except for films deposited at 400 °C. Best film is the fully c-axis oriented AZO/STO deposited at 300 °C, with electrical conductivity 310 S/cm, Seebeck coefficient -65 μV/K and power factor 0.13 × 10-3 Wm-1K-2 at 300 K. Its performance increases with temperature. For instance, power factor is enhanced up to × 10-3 Wm-1K-2 at 600 K, surpassing the best AZO film previously reported in literature.
In our previous work, low resistance state (LRS) and high resistance state (HRS) areas on a nickel-oxide (NiO) film formed by applying a voltage using conductive atomic-force microscopy (C-AFM) was observed by scanning electron microscope (SEM). Comparing the observed secondary electron image (SEI) contrast to the report about the dopant-type dependence of SEI contrast reported on silicon, it was suggested that the LRS and HRS areas are, respectively, electrochemically induced p-type Ni1-xO (x > 0) and intrinsic (stoichiometric) or ntype Ni1-xO (x ≤ 0). In this paper, we verified that resistance change caused by C-AFM is due to electrochemically induced carrier injection. Reduction effect of H2 annealing on the writing area, voltage dependence of depletion layer capacitance formed between the writing area and AFM-tip using scanning nonlinear dielectric microscopy (SNDM), and the effect of Schottky barrier formation between the writing area and thin metal layer on SEI contrast were investigated. Based on these results, it was clarified that the LRS and HRS areas are, respectively, p-type Ni1-xO (x > 0) and intrinsic (stoichiometric) or n-type Ni1-xO (x ≤ 0)
Strongyloides ratti (Nagoya strain) is unique in that a portion of adults parasitizing the small intestine withstands ‘worm expulsion’, which starts at around day 8 post-infection (p.i.) by host immunity, and establishes in the large intestine after day 19 p.i. To investigate the mechanism, adults obtained from the small intestine at day 7 or 19 p.i. were transplanted into the colon of infection-primed immune rats. Adults obtained at day 7 p.i. were rejected quickly, whereas those obtained at day 19 p.i. could establish infection. Moreover, the body length and the number of intrauterine eggs increased in the large intestine. In a separate experiment, large intestinal parasitism was abolished by the treatment of host rats with an anti-oxidant, butylated hydroxyanisole. These results indicate that small intestinal adults between days 7 and 19 p.i. acquired the ability to parasitize the large intestine of immune rats, and that free radicals produced by the host may have played a significant role in the process.
This study considers a Hybrid
Electrical Vehicle supplied by a Fuel Cell stack and supercapacitors used as
Storage Element. In such an application, real time energy management is of
paramount importance in order to increase autonomy and be able to deal
on-line with perturbed power demand. Many offline power flow optimization
principles are available but online algorithms are preferred and should be
derived for optimal management of the instantaneous power splitting between
the different available power sources. Based on particle swarm optimization
algorithm, this study defines the parameters tuning of such algorithm. The
final power splitting allows not only recovering energy braking but also is
robust to some disturbances occurring during the trip. The solution provides
good-quality and high-robustness results in a certain class of mission
profile and power disturbance.
Influence of the linear energy-momentum relationship in graphene on conductance and magnetoresistance (MR) in ferromagnetic metal (FM)/graphene/FM lateral junctions is studied in a numerical simulation formulated using the Kubo formula and recursive Green’s function method in a tight-binding model. It is shown that the contribution of electron tunneling through graphene should be considered in the electronic transport in metal/graphene/metal junctions, and that the Dirac point (DP) is effectively shifted by the band mixing between graphene and metal electrodes. It is shown that MR appears due to spin-dependent shift of DP or spin-dependent change in the electronic states at DPs. It is shown that the MR ratio caused by the latter mechanism can be very high when certain transition metal alloys are used for electrodes. These results do not essentially depend on the shape of the junction structure. However, to obtain high MR ratios, the effects of roughness should be small.
Exchange coupling observed recently in Fe/ Fe3O4 (001) junctions shows comparable intensity to that in Co/Ru/Co trilayers, and has potential applicability to spintronics devices. To clarify the mechanism of the exchange coupling, electronic and magnetic states of Fe/ Fe3O4 junctions are calculated in the first principles method by assuming four junction structures of bcc Fe and Fe3O4 layers. It is shown that the local moments of bcc Fe atoms at the interface increase, but those of Fe ions at the interface of Fe3O4 layer decrease. The total energy of the junctions is plotted as a function of distance between Fe and Fe3O4 layers. Calculated results of the coupling energy between Fe and Fe3O4 layers, however, are larger than experimental ones by two orders of magnitude, and they correspond to inter-atomic exchange interactions at the interface. In order to explain the experimental results, we propose a mechanism of exchange coupling mediated by impurity-like states of interfacial Fe atoms which possess reversed magnetic moments in bcc Fe layer. Frustration effects in exchange coupling between Fe and Fe3O4 layers are also discussed.
Rapid development in the area of low-temperature fuel cells has led to increased attention on catalyst synthesis with cost effective and environmentally-benign technology (green chemistry). In this study, a highly dispersed palladium nanoparticle catalyst was successfully prepared on a bacterial cell support by a single-step, room-temperature microbial method without dispersing agents. The metal ion reducing bacterium Shewanella oneidensis were able to reduce palladium ions into insoluble palladium at room temperature when formate was provided as the electron donor. The prepared biomass-supported palladium nanoparticles were characterized for their catalytic activity as anodes in polymer electric membrane fuel cell for power production. The maximum power generation of the biomass-supported palladium catalyst was up to 90% of that of a commercial palladium catalyst.
Colonization factors (CFs) mediate attachment of enterotoxigenic Escherichia coli (ETEC) to the intestinal mucosa and induce protective immunity against ETEC diarrhoea. We designed CF-specific polymerase chain reaction (PCR) primers, and developed a simple PCR-based genotypic CF identification method. ETEC strains (n=17) isolated from patients with diarrhoea in Thailand were examined for genotypical identification of CFs of ETEC strains. Coli surface antigen 6 (CS6) was the most common CF (29%), followed by CS13 (12%), colonization factor antigen I (CFA/I), CS2 and CS3, and CS17/CS19 (6% each), while 41% of the strains were negative. This simple PCR method for the detection of CF genes is useful for surveillance of ETEC infections in diagnostic laboratories.
We have demonstrated that scanning nonlinear dielectric microscopy (SNDM) exhibited high performance and high resolution in observing the dopant concentration profile of transistors. In this study, good quantitative agreement between the SNDM signals and dopant density values obtained by SIMS in standard Si samples, which dopant concentrations have been calibrated. We succeeded in visualizing high-resolution dopant profiles in n- and p-type MOSFET with 40 nm gate channels. It is considered that SNDM would be an effective method in measuring the quantitative two-dimensional dopant profiles of transistors. Finally, we have succeeded in detecting the dopant profiles of SRAM memory cell transistors.