The aim of the present study was to compare the rate of preterm birth (PTB) and growth from birth to 18 years between twins conceived by in vitro fertilization (IVF) and twins conceived by spontaneous conception (SC) in mainland China. The retrospective cohort study included 1164 twins resulting from IVF and 25,654 twins conceived spontaneously, of which 494 from IVF and 6338 from SC were opposite-sex twins. PTB and low birth weight (LBW), and growth, including length/height and weight, were compared between the two groups at five stages: infancy (0 year), toddler period (1–2 years), preschool (3–5 years), primary or elementary school (6–11 years), and adolescence (10–18 years). Few statistically significant differences were found for LBW and growth between the two groups after adjusting for PTB and other confounders. Twins born by IVF faced an increased risk of PTB compared with those born by SC (adjusted odds ratio [aOR] 8.21, 95% confidence interval [CI] [3.19, 21.13], p < .001 in all twins and aOR 10.12, 95% CI [2.32, 44.04], p = .002 in opposite-sex twins). Twins born by IVF experienced a similar growth at five stages (0–18 years old) when compared with those born by SC. PTB risk, however, is significantly higher for twins conceived by IVF than those conceived by SC.

Quasar black hole masses are most commonly estimated using broad emission lines in single epoch spectra based on scaling relationships determined from reverberation mapping of small samples of low-redshift objects. Several effects have been identified requiring modifications to these scaling relationships, resulting in significant reductions of the black hole mass determinations at high redshift. Correcting these systematic biases is critical to understanding the relationships among black hole and host galaxy properties. We are completing a program using the Gemini North telescope, called the Gemini North Infrared Spectrograph (GNIRS) Distant Quasar Survey (DQS), that has produced rest-frame optical spectra of about 200 high-redshift quasars (z = 1.5–3.5). The GNIRS-DQS will produce new and improved ultraviolet-based black hole mass and accretion rate prescriptions, as well as new redshift prescriptions for velocity zero points of high-z quasars, necessary to measure feedback.

The Chinese National Twin Registry (CNTR), initiated in 2001, has now become the largest twin registry in Asia. From 2015 to 2018, the CNTR continued to receive Chinese government funding and had recruited 61,566 twin-pairs by 2019 to study twins discordant for specific exposures such as environmental factors, and twins discordant for disease outcomes or measures of morbidity. Omic data, including genetics, genomics, metabolomics, and proteomics, and gut microbiome will be tested. The integration of omics and digital technologies in public health will advance our understanding of precision public health. This review introduces the updates of the CNTR, including study design, sample size, biobank, zygosity assessment, advances in research and future systems epidemiologic research.

Active Galactic Nuclei (AGN) exhibit multi-wavelength properties that are representative of the underlying physical processes taking place in the vicinity of the accreting supermassive black hole. The black hole mass and the accretion rate are fundamental for understanding the growth of black holes, their evolution, and the impact on the host galaxies. Recent results on reverberation-mapped AGNs show that the highest accretion rate objects have systematic shorter time-lags. These super-Eddington accreting massive black holes (SEAMBHs) show BLR size 3-8 times smaller than predicted by the Radius-Luminosity (R-L) relationship. Hence, the single-epoch virial black hole mass estimates of highly accreting AGNs have an overestimation of a factor of 3-8 times. SEAMBHs likely have a slim accretion disk rather than a thin disk that is diagnostic in X-ray. I will present the extreme X-ray properties of a sample of dozen of SEAMBHs. They indeed have a steep hard X-ray photon index, Γ, and demonstrate a steeper power-law slope, ασx.

In this paper, we consider two innovative structured matrices, CUPL-Toeplitz matrix and CUPL-Hankel matrix. The inverses of CUPL-Toeplitz and CUPL-Hankel matrices can be expressed by the Gohberg-Heinig type formulas, and the stability of the inverse matrices is verified in terms of 1-, ∞- and 2-norms, respectively. In addition, two algorithms for the inverses of CUPL-Toeplitz and CUPL-Hankel matrices are given and examples are provided to verify the feasibility of these algorithms.

Picoeukaryotes (<2–3 μm) perform key roles for the functioning of marine ecosystems, but little is known regarding the composition and diversity of picoeukaryotes in aquaculture areas. In this study, the Illumina MiSeq platform was used for sequencing the V4 variable region within the 18S rDNA gene to analyse genetic diversity and relative abundance of picoeukaryotic communities in the Qinhuangdao scallop cultivation area of the Bohai Sea. The community was dominated by three super groups, the alveolates (54%), stramenopiles (41%) and chlorophytes (3%), and three groups, dinoflagellates (54%), pelagomonadales (40%) and prasinophytes (3%). Furthermore, a contrasting station with open water away from the eutrophic aquaculture area was chosen. The communities collected from the two stations exhibited significant differences, with higher diversity in the aquaculture area. These results provide the first snapshot of the picoeukaryotic diversity in surface waters of the Qinhuangdao scallop cultivation area, and basic data for future studies on picoeukaryote community in an aquaculture region.

Two sets of reciprocal introgression lines (ILs) and a population of recombinant inbred lines (RILs) derived from the cross between japonica cultivar Xiushui09 and indica breeding line IR2061-520-6-9 (abbreviated as IR2061) were used to identify QTL for heading date (HD). Phenotyping was conducted in Hainan Island for two winter seasons (2007 and 2009). Nine QTLs were detected in the ILs with Xiushui09 background (XS-ILs), and four of which were repeatedly mapped across 2 years. Five QTLs were identified in the ILs with IR2061 background (IR-ILs), and three of which were commonly detected in 2 years. All commonly detected QTL had the same direction of gene effect. Seven QTL for HD were identified in the RILs in 2009. Only three (25%) QTLs were commonly detected using all the three populations (XS-ILs, IR-ILs and RILs). The number of commonly identified QTLs among populations was related to degree of similarity of their genetic backgrounds, suggesting that the genetic background effect is important for detecting HD QTL. QHd7 and QHd10b stably expressed in different populations and across years thus would be exploited in rice breeding programme. Moreover, lines with both of QHd7 and QHd10b resulted in at least 3 days earlier than lines with only one of them QTL, showing evident pyramiding effect.

We derive the mass function of supermassive black holes (SMBHs) over the redshift range 0 > z ≲ 2, using the latest deep luminosity and mass functions of field galaxies. Applying this mass function, combined with the bolometric luminosity function of active galactic nuclei (AGNs), into the the continuity equation of SMBH number density, we explicitly obtain the mass-dependent cosmological evolution of the radiative efficiency for accretion. We suggest that the accretion history of SMBHs and their spins evolve in two distinct regimes: an early phase of prolonged accretion, plausibly driven by major mergers, during which the black hole spins up, then switching to a period of random, episodic accretion, governed by minor mergers and internal secular processes, during which the hole spins down. The transition epoch depends on mass, mirroring other evidence for “cosmic downsizing” in the AGN population.

Vitamin D is known for maintaining Ca homeostasis and bone structure, and may also decrease susceptibility to chronic and infectious diseases. However, data on vitamin D status and its predictors among Southeast Asian populations are limited. We evaluated the distribution and determinants (genetic and environmental) of serum 25-hydroxyvitamin D (25(OH)D) concentrations among 504 middle-aged and elderly participants (aged 45–74 years) in the Singapore Chinese Health Study. Data on dietary and other lifestyle factors were collected by trained interviewers. Serum 25(OH)D concentrations and genetic polymorphisms in vitamin D metabolism pathway enzymes (cytochrome P450 (CYP) 2R1, 3A4, 27B1, 24A1; vitamin D binding protein (also known as group-specific component, GC); and vitamin D receptor) were measured using stored biospecimens. Mean 25(OH)D concentration was 68·8 nmol/l. Serum 25(OH)D concentrations were positively associated with dietary vitamin D intake, and inversely associated with hours spent sitting at work. BMI was not associated with 25(OH)D concentrations. CYP2R1 rs10741657, rs12794714, rs1993116; CYP3A4 rs2242480; and GC rs4588, rs7041, rs16847015, rs2298849 were statistically significantly associated with 25(OH)D concentrations. Individuals with the Gc2-2 haplotype (rs4588AA/rs7041TT) had statistically significantly lower 25(OH)D concentrations compared to all other Gc haplotypes (P-trend < 0·001). The majority of participants (86 %) had 25(OH)D concentrations ≥ 50 nmol/l, which is consistent with the 2011 Institute of Medicine (US) recommendation for bone health, and 32 % had concentrations of ≥ 75 nmol/l that are thought to be required for broader health effects. Dietary vitamin D intake, hours spent indoors at work and genetic variation in CYP2R1, CYP3A4 and GC are significant predictors of 25(OH)D concentrations among Singapore Chinese.

The Dorset ram of the callipyge phenotype presents with muscular hypertrophy in the buttocks, and its inheritance is polar overdominant. A partial DNA fragment of 250 bp was obtained from the goat (Capra hircas) callipyge gene (CLPG; GenBank accession no. EU753362), which shared 96.04% and 88.65% identity with the corresponding regions of ovine (Ovis aries) and porcine CLPG, respectively. A polymorphism in the DNA fragment was detected by polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP). Sequencing results indicated no A→C mutation corresponding to the ovine CLPG gene, although one A→C transversion was located 147 bp downstream from the CLPG site. The polymorphism, named SNP216 after its position (where SNP indicates single-nucleotide polymorphism), was investigated in Boer (n=63), Laiwu Black (n=70), Lubei White×Boer Hybrid (n=40), Lubei White (n=29) and Inner Mongolia Alashan White cashmere (n=115) goat populations. The results indicated that allele A was dominant in four of the goat populations, the Inner Mongolia Alashan White cashmere goats being the exception. The first four populations were in a state of Hardy–Weinberg equilibrium (P>0.05). In Inner Mongolia Alashan White cashmere goats, least-square means of birth weight, production of cashmere and body weight gain from birth to weaning did not differ significantly between the AA and AC phenotypes (P>0.5).

A set of 146 representative adzuki (Vigna angularis var. angularis and var. nipponensis) germplasm from six Asian countries with a tradition of adzuki bean production, together with an outgroup standard rice bean (Vigna umbellata), were analysed by amplified fragment length polymorphism (AFLP) methodology using 12 informative primer pairs. A total of 313 unambiguous polymorphic bands were created. According to the dendrogram, using cluster analysis based on AFLP banding, 143 of the accessions were distinct and revealed enough genetic diversity for identification and classification of accessions within Vigna angularis. A neighbour-joining tree was generated using the newly developed Innan's nucleotide diversity estimate from the AFLP data. From analysis, seven distinct evolutionary groups, named ‘Chinese cultivated’, ‘Japanese cultivated’, ‘Japanese complex-Korean cultivated’, ‘Chinese wild’, ‘China Taiwan wild’, ‘Nepal- Bhutan cultivated’ and ‘Himalayan wild’, were detected. Nucleotide diversity with geographical distribution of each group is discussed, regarding the evolutionary relationships between wild and cultivated adzuki beans. The preliminary results indicated that cultivated adzuki beans have been domesticated from at least four progenitors with at least three geographical origins.

In this work, we report on silver nanocubes with perfect shape prepared by a simple poly(vinyl pyrrolidone)-directed polyol synthesis process. The effects of poly(vinyl pyrrolidone)/AgNO3ratio Rand reaction temperature Ton the morphology and size of the products were investigated. Ag nanocubes with an average edge length of 230 nm were obtained successfully with sharp edges and corners under a precise synthesis condition of R= 1 and T= 150 °C. The optical properties of Ag nanocubes show an attractive plasma resonance red-shift with size in a wide spectra region. The growth mechanism of the Ag nanocubes is proposed to be thermodynamically and kinetically controlled.

We investigated adsorption and dissociation of water and HfCl4 on a Ge/Si(100) −(2 × 1) surface with a density-functional theory. The Si–Ge and Ge–Ge homodimers are used to represent the Si1−xGex surface. (i) Water first adsorbs on the bare Ge/Si(100) − (2 × 1) surface and then dissociates into OH and H. The activation energy for adsorption of water on the Ge–Ge homodimer is much higher than that on the Si–Ge heterodimer. (ii) HfCl4 dissociates upon adsorption on the Ge/Si(100) − (2 × 1) surface into HfCl3 and Cl. No net activation barrier exists during the adsorption of HfCl4 on both SiGe surface dimers. The molecular adsorption state is found to be metastable according to the calculation, which implies that the reaction tends to move toward to the product rather than trapping in HfCl4 adsorbed state. The difference in the potential energy surface between reactions on Si–Ge and Ge–Ge dimers is due to different bond strengths.

After examining ternary Al-based quasi-crystalline phase diagrams, we pointed out that the presence of e/a-constant and e/a-variant lines is a common phenomenon. Ternary quasi-crystal compositions are located at the crossing point of these lines in ternary phase diagrams. Such an empirical rule can be used to predict the ternary quasi-crystal compositions from binary ones. We applied this rule to the Al–Fe–Ni system and clarified the decagonal phase composition zone. There are two decagonal phases, D-Al72.5Fe14.5Ni13 and D′-Al705Fe12Ni17.5, that correspond respectively to Al–Fe-based and Al–Ni-based decagonal phases in the same ternary system.

Part of the energy of low solar corona may be released and converted to plasma energy that may be the dominant source of solar flares. Recently, many physical mechanisms have been proposed to accelerate ions and electrons. In the magnetic mirror device of fusion research, ion cyclotron instability and the energetic ion losses have been discovered and the plasma becomes electron rich.