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A simple chemical method of acid treatment has been developed for cutting graphene oxide into graphene oxide quantum dots with controllable size (∼3.0 nm). The newly produced graphene oxide quantum dots have high stability and disperse well in water for several months. Bright blue emission, as well as an excitation-dependent photoluminescence activity, is observed in the GOQDs. In contrast, the photoluminescence emission of graphene quantum dots obtained by the reduction of graphene oxide quantum dots has a distinctive blue shift when compared with that of the graphene oxide quantum dots. The difference in PL properties between graphene oxide quantum dots and graphene quantum dots can be attributed to the change of the bandgap due to the different size of the isolated sp2 cluster in the sp3 matrix of graphene.

Spin-dependent thermoelectric transport properties have been experimentally studied on a micro-structured device based on epitaxially grown 75-nm-thick Co2Ti0.6V0.4Sn0.75 Heusler film with integrated heater and thermometers. The anomalous Nernst coefficient is found to be 0.5 μV/K at 50 K. Thermoelectric power in both longitudinal and transverse directions have been measured with magnetic field rotated in-plane. Asymmetric peaks and valleys are observed at particular in-plane field angle around 25 K. These anomalous peaks show novel magnetic hysteresis due to the interplay between the magnetization and the temperature gradient. These complex behaviors of thermoelectric effect during magnetization reversal still need to be understood.

Little is known on the extent of weight misperception and its relation with dietary intake among Chinese youth.The study aimed to investigate extent and correlates of weight misperception and its relation with dietary intake among Chinese youth.Data pertaining to Chinese youth, 6-17 years of age, from the 2004-2009 China Health and Nutrition Survey (N = 3,923) were analyzed using STATA version 12.1. The heights and weights of the participants were measured by well-trained health workers at the participants' homes or a local clinic following the reference protocol recommended by the World Health Organization. The dietary intake data of the participants were collected on three consecutive days at both the household and individual levels.Of the children 6-11 years of age, 18.9% were underweight and 15.3% were overweight. Among the children 12-17 years of age, 18.3% were underweight and 8.1% were overweight. Less than 60 % of Chinese youth accurately estimated their weight status. Nutrition knowledge was positively related to a perception of being overweight (adjusted odds ratio [AOR] = 1.98, p = .007) among children 12-17 years of age. A perception of being overweight was positively associated with fat and protein intake among children 6-11 years of age (p .05).A discrepancy exists between the actual and perceived weight status of Chinese youth. Efforts are needed in China to promote accurate weight perception, healthy weight, and eating behaviors.

There is a paucity of recent data on Chinese childhood overweight and underweight prevalence especially since 2004.The purpose of this study was to examine trends in underweight and overweight/obesity ("overweight" hereafter) prevalence and energy balance-related behaviors of Chinese youth from 2004 to 2009.Data from the China Health and Nutrition Survey, 2004-2009 (N = 4,061 students aged 6-18 years), were analyzed. Trained health workers took anthropometric measures at the participant's house or at a local clinic following a reference protocol recommended by the World Health Organization. The international age- and sex-specific body mass index reference standard proposed by the International Obesity Task Force was used to define underweight and overweight children in this study.Among 6- to 11-year-old boys, underweight prevalence increased from 14.5% (2004) to 20.1% (2009, p = 0.068). Among 12- to 18-year-old boys, however, overweight prevalence increased from 7.5 to 12.6% (p = 0.034). From 2004 to 2009, after-school sedentary behavior increased from 2.3 to 3.4 h/day for 6- to 11-year-olds (p 0.001) and from 2.2 to 3.1 h/day for 12- to 18-year-olds (p 0.01). Meanwhile, the total energy intake decreased 7% for 6- to 11-year-olds (p 0.05) and 10% for 12- to 18-year-olds (p 0.01).Both underweight and overweight Chinese students are increasing, with underweight increases more pronounced in 6- to 11-year-olds and overweight increases more pronounced in 12- to 18-year-olds. Nationwide efficacious interventions are needed that improve the diet, decrease sedentary behavior, and encourage a healthy and realistic body image in Chinese youth.

We study the intervalley scattering in defected graphene by low-temperature transport measurements. The scattering rate is strongly suppressed when defects are charged. This finding highlights "screening" of the short-range part of a potential by the long-range part. Experiments on calcium-adsorbed graphene confirm the role of a long-range Coulomb potential. This effect is applicable to other multivalley systems, provided that the charge state of a defect can be electrically tuned. Our result provides a means to electrically control valley relaxation and has important implications in valley dynamics in valleytronic materials., Comment: 13 pages, 4 figures

We study the axis transport of WTe2. An enhancement of quantum oscillations allows for observation of an astonishing spin zero effect at certain field orientations for both hole bands and electron bands, providing transport evidence for their spin–orbit splitting origin. Based on the requirements for the spin zero effect, a lower limit for the Lande g-factor, as large as 44.7, has been obtained at a field angle of 63.7° with respect to the c axis towards the b axis for the hole band. The field dependence of the band splitting is experimentally determined.

ZrTe$_5$ is a newly discovered topological material. Shortly after a single layer ZrTe$_5$ had been predicted to be a two-dimensional topological insulator, a handful of experiments have been carried out on bulk ZrTe$_5$ crystals, which however suggest that its bulk form may be a three-dimensional topological Dirac semimetal. We report the first transport study on ultra thin ZrTe$_5$ flakes down to 10 nm. A significant modulation of the characteristic resistivity maximum in the temperature dependence by thickness has been observed. Remarkably, the metallic behavior, occurring only below about 150 K in bulk, persists to over 320 K for flakes less than 20 nm thick. Furthermore, the resistivity maximum can be greatly tuned by ionic gating. Combined with the Hall resistance, we identify contributions from a semiconducting and a semimetallic bands. The enhancement of the metallic state in thin flakes are consequence of shifting of the energy bands. Our results suggest that the band structure sensitively depends on the film thickness, which may explain the divergent experimental observations on bulk materials., 17 pages, 9 figures

The nodal signaling pathway has been shown to play crucial roles in inducing and patterning the mesoderm and endoderm, as well as in regulating neurogenesis and left-right axis asymmetry. Here, we present the first complete cDNA and genomic sequences as well as the promoter predication of the Dnah9 gene in the Japanese flounder. The 15,558-bp-long cDNA is divided into 96 exons and spread over 138 kb of genomic DNA. Protein sequence comparison showed that it shares higher identity with other vertebrate orthologs, with an ATP binding dynein motor, AAA domain and microtubule binding stalk of dynein motor. Dnah9 exhibited maternal and ubiquitous expression in all cells of the early development stages, but became concentrated in the head at 1 DAH, as identified by qRT-PCR and in situ hybridization methods. Furthermore, after nodal signaling was inhibited, the level of Southpaw did not change significantly at early development stage (50 % epiboly) but increased significantly at late stages (27-somite stages and 1 DAH), as well as the expression of Lefty, an inhibitor of nodal signaling, increased continuously. On the other hand, the expression level of Dnah9 decreased. The transcription factor binding site of FAST-1 (SMAD interacting protein) was identified in the transcription region of Dnah9 by the promoter analysis, which might format the complexes of SMADs, FAST-1 and the transcription region of Dnah9 served as a bridge of Dnah9 and nodal signaling. All evidences indicated that Dnah9 might be downstream of nodal during the early development stages, and an indirect function through SMADs for nodal signaling pathway.

Enhancement of the spin-orbit coupling in graphene may lead to various topological phenomena and also find applications in spintronics. Adatom adsorption has been proposed as an effective way to achieve the goal. In particular, great hope has been held for indium in strengthening the spin-orbit coupling and realizing the quantum spin Hall effect. To search for evidence of the spin-orbit coupling in graphene adsorbed with indium adatoms, we carry out extensive transport measurements. It is found that indium adatoms dope graphene and introduce significant Coulomb scattering. No signature of the spin-orbit coupling is observed in the weak localization magnetoconductance and nonlocal spin Hall effect. Possible explanations are discussed.

Antarcticite, CaCl2 · 6H2O, is an ideal phase change material (PCM) due to its high-energy storage density and good thermal conductivity. In this chapter, supercooling and subsequent solidification behavior of antarcticite are studied based on the cooling curve method and DSC measurement. The results show that the minor SrCl2 · 6H2O as the nucleator and carboxymethyl cellulose as the thickening agent could significantly reduce supercooling and partly restrain the phase separation. Moreover, we incorporated antarcticite as PCM into building envelopes in four different cases, and the simulation of the heat transfer processes showed that the temperature fluctuation could be reduced to about 2 °C in the best case.

To investigate the significance of beta-adrenergic receptor 2 (beta2-AR) and vascular endothelial growth factor-2 (VEGFR-2) in the occurrence and development of infantile hemangioma through detecting the expression of beta2-AR and VEGFR-2 in the different stages of infantile hemangiomas.According to the Mulliken's classification standard, we classified the specimens as proliferating group (32 cases), involuting group (17 cases) and involuted group (11 cases). Normal skin tissue surrounding the hemangioma from 7 cases were chosen as control group. The expression of beta2-AR and VEGFR-2 was detected by immunohistochemical technique in proliferating hemangioma, involuting hemangioma, involuted hemangioma. The mean optical density was measured by image analysis system (Image Pro Plus 6.0) and SPSS 16.0 software was applied for statistical analysis.The expression of beta2-AR and VEGFR-2 was strongly positive in proliferating hemangioma, while positive in involuting hemangioma and weakly positive in the involuted stage. The mean optical density of each phase was 0.064 751 2 +/- 0.012 747, 0.031 6017 +/- 0.006 848,0.011 869 8 +/- 0.039 349 for beta2-AR, and 0.068 940 9 +/- 0.029 274, 0.028 445 5 +/- 0.006 396, 0.011 184 1 +/- 0.004 198 for VEGFR-2. The differences between different stages had a statistically significance (P0.05). Correlation analysis on the mean optical density between beta2-AR and VEGFR-2 had a statistically significance (P0. 05).Beta2-AR and VEGFR-2 may be involved in the occurrence and development of infantile hemangioma.

Background: Internet-based interventions are more cost-effective than conventional interventions and can provide immediate, easy-to-access, and individually tailored support for behavior change. Waist circumference is a strong predictor of an increased risk for a host of diseases, such as hypertension, diabetes, and dyslipidemia, independent of body mass index. To date, no study has examined the effect of Internet-based lifestyle interventions on waist circumference change. Objective: This study aimed to systematically review the effect of Internet-based interventions on waist circumference change among adults. Methods: This meta-analysis reviewed randomized controlled trials (N=31 trials and 8442 participants) that used the Internet as a main intervention approach and reported changes in waist circumference. Results: Internet-based interventions showed a significant reduction in waist circumference (mean change –2.99 cm, 95% CI −3.68 to −2.30, I 2 =93.3%) and significantly better effects on waist circumference loss (mean loss 2.38 cm, 95% CI 1.61-3.25, I 2 =97.2%) than minimal interventions such as information-only groups. Meta-regression results showed that baseline waist circumference, gender, and the presence of social support in the intervention were significantly associated with waist circumference reduction. Conclusions: Internet-based interventions have a significant and promising effect on waist circumference change. Incorporating social support into an Internet-based intervention appears to be useful in reducing waist circumference. Considerable heterogeneity exists among the effects of Internet-based interventions. The design of an intervention may have a significant impact on the effectiveness of the intervention. [J Med Internet Res 2015;17(7):e181]

Impurity doping plays a pivotal role in semiconductor electronics. We study the doping effect in a two-dimensional semiconductor, gapped bilayer graphene. By employing in situ deposition of calcium on the bilayer graphene, dopants are controllably introduced. Low temperature transport results show a variable range hopping conduction near the charge neutrality point persisting up to 50 K, providing evidence for the impurity levels inside the gap. Our experiment confirms a predicted peculiar effect in the gapped bilayer graphene, i.e., formation of in-gap states even if the bare impurity level lies in the conduction band. The result provides perspective on the effect of doping and impurity levels in semiconducting bilayer graphene.

Among the chemical doping elements, nitrogen atoms play a critical role in tuning the intrinsic properties or exploiting new phenomena of carbonaceous materials. Herein, we report a facile strategy to synthesize nitrogen-doped carbon dots (NCDs) using glutamic acid as the precursor via a one-step thermal conversion process. The as-produced NCDs exhibit bright blue photoluminescence (the quantum yield of ca. 23.2%), and the emission wavelength could be slightly tuned through changing the parameters of the synthesizing process. Interestingly, apart from their superior luminescence characters, unexpected cathodoluminescence (CL) and frequency upconverted emission properties were both observed in the NCDs.