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Plyometric exercise and bone health in children and adolescents: a systematic review

World Journal of Pediatrics 2017年第2期13卷 112-121页

作者： Alejandro Gómez-Bruton (A)ngel Matute-Llorente Alejandro González-Agüero JoséA.Casajús Germán Vicente-Rodríguez growth ExerciseNutrition and Development(GENUD)Research GroupUniversity of ZaragozaZaragozaSpain Faculty of Health and Sport Sciences(FCSD) Department of Physiatry and NursingUniversity of ZaragozaRonda Misericordia 522001-HuescaSpain growth ExerciseNutrition and Development(GENUD)Research GroupUniversity of ZaragozaZaragozaSpain

Background:Many jumping interventions have been performed in children and adolescents in order to improve bone-related variables and thus,ensure a healthy bone development during these periods and later in *** systematic review aims to summarize and update present knowledge regarding the effects that jumping interventions may have on bone mass,structure and metabolism in order to ascertain the efficacy and durability (duration of the effects caused by the intervention) of the *** sources:Identification of studies was performed by searching in the database MEDLINE/PubMed and *** studies were identified by contacting clinical experts and searching bibliographies and *** terms included 'bone and bones','jump*','weight-bearing','resistance training' and 'school intervention'.The search was conducted up to October *** studies that had performed a specific jumping intervention in under 18-year olds and had measured bone mass were *** extraction of articles was done by 2 authors using predefined data ***:A total of 26 studies were included in this ***-four studies found positive results as subjects included in the intervention groups showed higher bone mineral density,bone mineral content and bone structure improvements than *** two studies found no effects on bone mass after a 10-week and 9-month ***,those studies that evaluated the durability of the effects found that some of the increases in the intervention groups were maintained after several ***:Jumping interventions during childhood and adolescence improve bone mineral content,density and structural properties without side *** type of interventions should be therefore implemented when possible in order to increase bone mass in early stages of life,which may have a direct preventive effect on bone diseases like osteoporosis later in fife.

关键词： adolescents bone mineral density intervention jumping osteoporosis

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Variability of European beech wood density as influenced by interactions between treering growth and aspect

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Forest Ecosystems 2016年第3期3卷 165-173页

作者： Daniela Diaconu Marc Wassenberg Heinrich Spiecker Chair of Forest growth and Dendroecology Albert-Ludwigs-University

Background： Wood density is considered to be the most important predictor of wood quality but despite its importance, diffuse-porous tree species have been the subject of only a limited number of studies. The importance of European beech forests for Central Europe calls for profound research to examine the potential impact of a warmer climate on the quality of beech timber. Methods： In this study we analysed the influence of tree-ring width and tree-ring age on the wood density of beech, and whether the wood density response to these two parameters is modified by aspect. A linear mixed-effects model for wood density was constructed for mean density data measured with high frequency densitometry on stem discs from 72 beech trees sampled from two different aspects （northeast -NE and southwest -SW） of a valley in southwestern Germany. Results： Part of the variability of mean annual wood density was explained by cambial age： an increase in cambial age resulted in an increase in mean wood density. Tree-ring width and aspect had only a small influence on wood density, Wood density on the SW aspect was lower than on the NE with a difference of approximately 0.006 g/cm3. The between-tree variability was very high. Conclusions： The significant interaction between cambial age and aspect reflects the importance of site conditions at older tree ages： with increasing cambial age the difference between aspects becomes stronger. Our results give a better understanding of the importance of site conditions on the wood quality of beech.

关键词： Fagus sylvatica HF densitometry Wood quality Wood density Aspect

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Preparation by chemical co-precipitation, spectral and electrical characteristics of neodymium orthophosphate nanoparticles

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Journal of Rare Earths 2015年第5期33卷 535-544页

作者： Seema Verma K.K.Bamzai Crystal growth and Material Research Laboratory Department of Physics & Electronics University of Jammu

Nanoparticles of neodymium orthophosphate （NdPO4） were prepared through a facile wet co-precipitation technique. The X-ray diffraction （XRD） studies revealed the material belonging to monoclinic monazite phase with crystallite size of 30.8 nm. Scanning electron microscopic studies showed that the material was composed of a large number of agglomerated spherical particles having grain size of 92 nm. Thermogravimetric analysis suggested that the structural phase transition was seen above 800 °C. The spectroscopic investigations were carried out using Fourier transform infrared spectroscopy （FTIR）. UV-VIS-NIR ab-sorption spectrophotometer showed various transitions from the ground state 4I9/2 to various excited states within the 4f shell and the optical band gap came out to be 3.3 eV. The dielectric constant （ε′）, dielectric loss （tanδ） and ac conductivity ln（σac） were measured in the frequency range of 5 kHz to 1 MHz and in the temperature range of 40 to 500 °C. The dielectric measurement suggested that there was a shift in the value of transition temperature （Tc）, thereby indicating relaxor behaviour of the material. The activation energy value decreased with increase in frequency, thereby suggesting the role of mixed ionic-polaronic conduc-tivity.

关键词： nanoparticles spectroscopic dielectric properties rare earths

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Carbon quantum dots/BiVO_4 composite with enhanced photocatalytic activity

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Science China(Technological Sciences) 2019年第2期62卷 356-360页

作者： ZHANG ZhiJie HUANG HaiRui XU JiaYue ZHANG Na ZHANG Cheng Institute of Crystal growth School of Materials Science and Engineering Shanghai Institute of Technology

In this study, we report the facile fabrication of a carbon quantum dots(CQDs)/BiVO_4 composite with efficient photocatalytic activity. Due to the excellent upconversion photoluminescence, as well as the photo-induced electron transfer and reservoir properties of CQDs, the CQDs/BiVO_4 composite exhibited superior photocatalytic performance in the degradation of rhodamine B(RhB) under the irradiation of simulated solar light. This study provides a strategy for the development of high-performance catalysts based on CQDs.

关键词： carbon quantum dots BiVO4 photocatalysis composite electron transfer

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Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan Zong Hui Li Ya‑Qin Zhang Department of growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic *** aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese *** A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in *** and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were *** The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒*** apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th *** total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,*** total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural *** The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒*** attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

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Normal reference ranges for semen quality and their relations to fecundity

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Asian Journal of Andrology 2010年第1期12卷 95-98页

作者： Niels E. Skakkebaek University Department of growth and Reproduction Rigshospitalet Copenhagen DK-2100 Denmark

Several recent studies have shown that the fecundity of a man decreases progressively with sperm concentrations below 40 million spermatozoa per mL. Therefore, it is unfortunate that the new World Health Organization guidelines for semen analysis recommend lowering the lower cutoff value for normal sperm concentration from 20 to 15 million spermatozoa per mL. As a result large groups of subfertile men across the world may not receive appropriate andrological help in the future.

关键词： semen quality infertility sperm morphology fecundity

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Success factors for high-quality oak forest(Quercus robur, Q. petraea) regeneration

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Forest Ecosystems 2019年第4期6卷 367-383页

作者： Andreas M?lder Holger Sennhenn-Reulen Christoph Fischer Hendrik Rumpf Egbert Sch?nfelder Johannes Stockmann Ralf-Volker Nagel Department A (Forest growth) Northwest German Forest Research Institute(NW-FVA)

Background: Within the framework of close-to-nature forestry, oak forest(Quercus robur, Q. petraea) regeneration techniques that consider both silvicultural and nature conservation demands have become a very important *** there are many experimental and local studies that aim at disentangling the relationships between different environmental and silvicultural factors and the success of oak regeneration, systematic supra-regional studies at the greater landscape level are missing so *** this background, the first objective(a) of this study was to present an efficient and sufficiently accurate sampling scheme for supra-regional forest regrowth inventories, which we applied to young oaks stands. The second, and major, objective(b) was to identify the crucial success factors for high-quality oak forest regeneration in northwest ***: Objective(a): Factors that have been identified as potentially crucial for the success or failure of oak regeneration were either included in a field inventory procedure or extracted from forest inventory databases. We found that the collected data were suitable to be analyzed in a three-step success model, which was aimed at identifying the crucial success factors for high-quality oak forest ***(b): Our modeling procedure, which included a Bayesian estimation approach with spike-and-slab priors,revealed that competitive pressure from the secondary tree species was the most decisive success factor;no competition, or low competition by secondary tree species appeared to be particularly beneficial for the success of high-quality oak regeneration. Also fencing and the absence of competitive vegetation(weeds, grass, bracken)seemed to be beneficial factors for the success of oak ***: Trusting in biological automation was found to be mostly useless regarding economically viable oak forest regeneration. To efficiently organize oak regeneration planning and silvicultural decision-ma

关键词： Close-to-nature forestry Competition Ecological continuity Forest inventory Forest management Plantplant interactions Quercus robur Quercus petraea Regeneration Silviculture

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The spectroscopic properties of Dy3+ and Eu3+ co-doped Y3Al5O12 （YAG）phosphors for white LED

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Progress in Natural Science:Materials International 2015年第3期25卷 209-214页

作者： Xuejiao Niu Jiayue Xu Yan Zhang Institute of Crystal growth School of Materials Science and Engineering Shanghai Institute of Technology

Tunable full color emissive Y32.94-xAl5O12: 0.06 Dy3+, xEu3+(YAG: 0.06 Dy, xEu) phosphors with emission peaks at 483 nm(blue), 582 nm(yellow) and 610 nm(red) were synthesized by a sol–gel method. The as-synthesized phosphors were characterized by X-ray powder diffraction(XRD), transmission electron microscopy(TEM), photoluminescence decay lifetimes, photoluminescence excitation and emission spectra. The results showed that photoluminescence intensity varied with excitation wavelength and the doping concentration of Eu3+. The co-doping with Eu3+ compensated the red emission component of the YAG: Dy3+ phosphor. The chromaticity coordinate of YAG: 0.06 Dy, 0.09 Eu phosphor(0.3263, 0.3334) was very close to that of the ideal white light(0.3333, 0.3333). Thus, the YAG: 0.06 Dy, 0.09 Eu phosphor can find potential application in simulating the sunlight artificially through fabricating white light emitters.

关键词： YAG Luminescence properties White light emitting diodes Optical materials

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growth and development of children in China:achievements,problems and prospects

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World Journal of Pediatrics 2024年第2期20卷 97-104页

作者： Xin-Nan Zong Hui Li Department of growth and Development Capital Institute of PediatricsBeijing 100020China

growth reflects the general condition of society,and is a measure of the nutritional and hygienic status of a population[1,2].Nutrition is one of the most important components of children’s well-being[3].The Chinese government attaches great importance to children’s health and development,with a clear statement and consistent practice for“Children are the future and hope of the motherland”.

关键词： mother statement children

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Phase transition and photoluminescence properties of Eu^3＋-doped ZnMoO4 red phosphors

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Science China(Technological Sciences) 2017年第10期60卷 1473-1479页

作者： ZHOU Yu ZHANG ZhiJie CHU YaoQing PAN YunFang YOU MingJiang ZHENG TingTing XU JiaYue Institute of Crystal growth School of Materials Science and Engineering Shanghai Institute of Technology Shanghai 201418 China

Eu3＋-doped ZnMoO4 with different doping concentrations were synthesized by a hydrothermal method. The effects of Eu3＋ doping on the phase structure and photoluminescence （PL） properties of ZnMoO4 were investigated. The result showed that the introduction of Eu3~ could lead to phase transition of ZnMoO4. With the increase of Eu3-- doping amount, [3-ZnMoO4 was transformed to ct phase gradually, which led to different photoluminescence performances. The optimized doping concentration of Eu3＋ was 6 mol% for the highest emission intensity at 615 nm. Its CIE chromaticity coordinates were （0.667, 0.331）, which were very close to the values of standard chromaticity （0.67, 0.33） for National Television Standards Committee （NTSC） system. Therefore, Eu3＋-doped ZnMoO4 is considered to be a promising red-emitting phosphor for white LED applications.

关键词： Eu3+-doped ZnMoO4 phase transition photoluminescence red phosphor LED

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