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BACKGROUND: In recent years, obesity and vitamin D deficiency are more prevalent among adolescents. Improving our knowledge of the link between vitamin D and visceral adipose tissue (VAT) is essential for the health of adolescents. This study aimed to examine the connection between serum vitamin D levels and VAT mass among adolescents participating in the United States. METHODS: This is a cross-sectional study that used data from the 2011 to 2015 National Health and Nutrition Examination Survey (NHANES). The connection between serum vitamin D levels and VAT was investigated using weighted multiple linear regression models. Potential nonlinear relationships were explored using smooth curve fitting. RESULTS: The analysis included 3171 adolescents aged 12-19 years. Vitamin D levels were shown to be inversely linked with VAT in the full-adjusted model (ß = - 0.34, 95% CI: - 0.49 to - 0.19). When stratified analyses by gender, this negative relationship persisted in the girls' group (ß = - 0.39, 95% CI: - 0.60 to - 0.19), but not in the boys' group (ß = - 0.06, 95% CI: - 0.25 to 0.13). When stratified analysis by race, this negative relationship persisted in the Mexican American group (ß = - 0.61, 95% CI: - 1.03 to - 0.19), and the non-Hispanic White group (ß = - 0.27, 95% CI: - 0.54 to - 0.01), but not in the other groups. CONCLUSIONS: Our findings confirmed that serum vitamin D levels negatively correlated with VAT among adolescents in the United State, especially in girls, the Mexican American and non-Hispanic White. Further research is needed to determine whether increasing serum vitamin D levels decrease VAT among adolescents.
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Grasa Intraabdominal , Deficiencia de Vitamina D , Masculino , Femenino , Adolescente , Humanos , Estados Unidos/epidemiología , Encuestas Nutricionales , Estudios Transversales , Deficiencia de Vitamina D/epidemiología , Vitamina D , VitaminasRESUMEN
The coordinated distribution of inorganic phosphate (Pi) between roots and shoots is an important process that plants use to maintain Pi homeostasis. SHORT-ROOT (SHR) is well characterized for its function in root radial patterning. Here we demonstrate a role of SHR in controlling Pi allocation from root to shoot by regulating PHOSPHATE1 in the root differentiation zone. We recovered a weak mutant allele of SHR in Arabidopsis that accumulates much less Pi in the shoot and shows a constitutive Pi starvation response under Pi-sufficient conditions. In addition, Pi starvation suppresses SHR protein accumulation and releases its inhibition on the HD-ZIP III transcription factor PHB. PHB accumulates and directly binds the promoter of PHOSPHATE2 to upregulate its transcription, resulting in PHOSPHATE1 degradation in the xylem-pole pericycle cells. Our findings reveal a previously unrecognized mechanism of how plants regulate Pi translocation from roots to shoots.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Mutación , Organofosfatos/metabolismo , Fosfatos/metabolismo , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Hair follicle stem cells are pluripotent and have a self-renewal capacity and multi-differentiation potential in vitro. As hair follicle stem cells can be easily sampled from the skin and hair of clinical patients at a considerable quantity, these cells have potential applications in wound repair and skin tissue engineering. Effective approaches for the in vitro culture and amplification of mouse hair follicle stem cells, as well as the in vitro osteogenic differentiation potential and cell source when obtaining mouse-separated cells were examined. Serial subculture was performed in different culture systems. Cell source was detected based on the relevant surface markers derived from mouse hair follicles at the gene and protein levels, and the differential potential was determined. The proliferative ability of hair follicle-derived stem cells obtained from mouse embryonic fibroblast (MEF)/keratinocyte serum-free medium (KSF)-conditioned medium was the highest among all culture systems. The induced group had a stronger osteogenic differentiation potential compared with the non-induced group, indicating that the cells obtained from MEF/KSF-conditioned medium were cells derived from the hair follicle dermal papilla. Therefore, the strong osteogenic differentiation potential of the hair follicle-derived mesenchymal stem cells was screened with MEF/KSF-conditioned culture medium following amplification, and biological characteristics similar to those of hair follicle dermal papilla cells were observed.
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Direct generation of ultrashort few-optical-cycle pulses in various wavelength regions has attracted great attention in recent decades. In this paper, generation of less than five-optical-cycle pulses from a Kerr-lens mode-locked ${\rm Yb}{:}{\rm CaYAlO}_4$ laser is demonstrated. Pumped by a 976 nm fiber laser, stable near-Fourier-transform-limited ultrashort soliton pulses centered around 1080 nm with a repetition rate of ${\sim}{113.7}\;{\rm MHz}$ were obtained. The obtained pulses have a pulse duration as short as 17 fs if a ${{\rm Sech}^2}$-shaped pulse profile is assumed, corresponding to about 4.68 optical cycles. To the best of our knowledge, this is the shortest pulse directly generated from mode-locked rare-earth-doped solid-state oscillators.
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OBJECTIVES: The aim of this study was to evaluate the association between caries experience in primary teeth and caries experience in permanent teeth in a longitudinal study. METHODS: Teeth were examined at 5 years of age and a follow-up examination was conducted 7 years later at 12 years of age in all children from Jiading District, Shanghai, China. A total of 1885 participants were recruited in the study; 1683 students were followed up and 202 students (10.7%) were lost to follow up. Data were analyzed using the chi-square test, t-test and risk ratio. RESULTS: The followed-up samples comprised 883 boys (52.5%) and 800 girls (47.5%). At initial examination, the prevalence of dental caries was 67.4% in boys and 66.5% in girls (χ² = 0.2, P = 0.70), with mean decayed, missing and filled teeth (dmft) scores of 3.5 ± 0.1 and 3.4 ± 0.1, respectively (t = 0.1, P = 0.90). At follow-up, the prevalence of dental caries was 33.9% in boys and 37.9% in girls (χ² = 2.9, P = 0.11), with mean DMFT scores in permanent teeth of 0.7 ± 0.0 and 0.8 ± 0.1, respectively (t = 1.2, P = 0.24). The group of 5-year-olds with caries had a significantly higher prevalence of caries in permanent teeth (45.5%) at 12 years of age than the group of 5-year-olds without caries (16.0%) (χ2 = 141.1, P < 0.001, risk ratio = 1.5). Caries risk in permanent teeth was significantly higher with greater dmft scores (χ2 for trend = 31.1, P < 0.001). CONCLUSIONS: Caries in primary teeth is a major risk factor for caries in permanent teeth. The likelihood of caries in permanent teeth is higher with greater dmft scores in primary teeth.
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An ultra-broadband graphene-gold film saturable absorber mirror (GG-SAM) with a spectral coverage exceeding 1300â nm is experimentally demonstrated for mode-locking of bulk solid-state lasers. Owing to the p-type doping effect caused by graphene-gold film interaction, the graphene on gold-film substrate shows a remarkably lower light absorption relative to pristine graphene, which is very helpful to achieve continuous-wave mode-locking in low-gain bulk lasers. Using the GG-SAM sample, stable mode-locking is realized in a Yb:YCOB bulk laser near 1â µm, a Tm:CLNGG bulk laser near 2â µm and a Cr:ZnSe bulk laser near 2.4â µm. The saturable absorption is characterised at an intermediate wavelength of 1.56â µm by pump-probe measurements. The as-fabricated GG-SAM with ultra-broad bandwidth, ultrafast recovery time, low absorption, and low cost has great potential as a universal saturable absorber mirror for mode-locking of various bulk lasers with unprecedented spectral coverage.
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We experimentally demonstrated a wavelength switchable passively mode-locked Yb:LuAG laser. The mode locked laser wavelength could be switched between 1031 nm and 1046 nm by a slit. With a coupler of 2% transmission, mode locked pulses with pulse duration of 1.15 ps and average output power of 1.3 W were generated at 1031 nm. By simply translating the slit position, 1046-nm mode locked pulses were generated with pulse duration of 252 fs and average output power of 676 mW. With the output coupler of 8% transmission, higher average output power of 2.2 W was generated at 1031 nm with pulse duration of 1.8 ps, which is the highest average output power ever reported for Yb:LuAG mode-locked lasers.
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Rayos Láser , Transferencia de Energía , Diseño de Equipo , Análisis de Falla de EquipoRESUMEN
PURPOSE: To evaluate the reliability of the digital models scanned by cone-beam computed tomography (CBCT). METHODS: Forty plaster models of patients with orthodontic treatment were selected. These plaster models were scanned and measured by 3DX cone beam CT, compared with manual measurement via concordance correlation coefficient (CCC) and mean difference (MD). RESULTS: The CCC of all the measurement was from 0.847 to 0.993. The value of MD of all the measurement was below 0.25mm except CFF6, PWF5 and PWF6, which was 0.34mm, 0.63mm and 1.49mm, respectively. CONCLUSIONS: The reliability and accuracy of the digital models scanned by cone-beam CT is very high. The accuracy of measurement of the dental cusp is the highest, the dental fossa is the second, and the lowest point of palatal gingival is the third.
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Tomografía Computarizada de Haz Cónico , Modelos Dentales , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Ortodoncia , Reproducibilidad de los ResultadosRESUMEN
We report on the fabrication and characterization of optical-stripe waveguides in neodymium-doped calcium barium niobate (Nd:CBN) crystals by using He ion implantation assisted with a mask. The guided-mode profiles are successfully modeled through numerical simulations. After annealing at 200 degrees C for 30 min, the waveguide propagation loss could be reduced down to ~3 dB/cm. Room-temperature microluminescence and micro-Raman investigations reveal that the crystal bulk features are well preserved in the active volume of the waveguide, suggesting possible applications as integrated photonic devices.
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A new passively self-Q-switched Nd, Cr:GdVO(4) laser crystal was grown by Czochralski method for the first time to our knowledge. Polarized absorption spectra were measured at room temperature. The absorption bands display polarization character and an absorption band of Cr(5+) ions at 1110 nm enables the crystal to be a self-Q-switched laser material at 1.06 mum. In the passive self-Q-switching operation, the maximum output power, shortest pulse width, and largest pulse energy were obtained to be 265 mW, 230 ns, and 1.12 microJ, respectively.
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Cristalización/métodos , Rayos Láser , Procesamiento de Señales Asistido por Computador/instrumentación , Diseño de Equipo , Análisis de Falla de EquipoRESUMEN
A new Q-switched crystal Cr(5+):GdVO(4) was grown by the Czochralski method for the first time, to our knowledge. Polarized absorption spectra of Cr(5+)+:GdVO(4) were measured at room temperature. The results showed that the crystal has polarized absorption properties, and the absorption band of pi-polarized spectra located at 900 to 1300 nm should be suitable as a passive saturable absorber Q-switched laser at about 1 mum. With Cr(5+):GdVO(4) as a saturable absorber, the pulsed laser performance of Nd:Lu(0.5)Gd(0.5)VO(4) at 1.06 mum was demonstrated. The maximum average output power of 122 mW was obtained under a pump power of 3.79 W. The shortest pulse width and largest pulse energy obtained were 361 ns and 0.77 muJ, respectively. To our knowledge, it is the first time the absorption spectra of Cr(5+):GdVO(4) and a pulsed laser with the crystal as the saturable absorber have been obtained.