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1.
Research suggests that cell phone use is related to sedentary behavior, that cell phone use during exercise reduces intensity, and that high frequency cell phone users are less fit than other users. Thus, cell phone use appears connected to health and fitness behaviors and should be better understood within this context. The present study investigated the sedentary nature of cell phone use, and examined the likelihood of cellphone use interfering with exercise behavior.DesignA validated survey was administered to a random sample of students from a public US university (N = 226).ResultsMean self-reported cell phone use was 380 min day−1, 87% reported cell phone use primarily occurs while sitting, and 70% of use was for leisure. Cell phone use was positively related to sedentary behavior (β = 0.30, p < 0.001). It was not related to physical activity. However, the likelihood of cell phone use during moderate (p = 0.006) and mild (p < 0.001) intensity exercise increased as cell phone use increased.ConclusionLike other screens (e.g., TVs), cell phone use appears to be a sedentary leisure behavior. Furthermore, high frequency use increases the likelihood that it will occur during exercise, likely lowering exercise intensity.  相似文献   
2.
通过调查分析晋西王家沟流域水源现状及人畜用水情况,提出了该区旱地果园的用水模式,即旱井集流节水栽培技术模式,这一模式首先利用现代材料和传统技术相结合的旱井修筑马天然降水贮存于旱井之中,然后采用节水保墒技术,充分把有限集流用于果园生产,提高了水的利用率和果园效益。  相似文献   
3.
从中部地区生态果园系统能量流动过程的分室模型出发,提出了对该类系统能量流动过程进行动态模拟的数学模型,并以孟州中部地区生态果园示范工程为实例完成了能量流动过程的模拟计算和实测分析.结果表明,该系统是一个渐进稳定的良性循环系统,输出能量趋于常数,其模拟计算结果与实测值相接近,误差小于0.65%,可直接应用于该类系统能流规律的预测研究.  相似文献   
4.
In recent years there has been a move in New Zealand to convert small, uneconomic orchards to other agricultural uses. Overseas research has demonstrated that copper from fungicide sprays often accumulates in the soils of orchards and can cause certain problems for plant growth and livestock. To date, no assessments appear to have been made of the degree of copper accumulation in such older orchards in New Zealand. This study presents the results of an assessment of two well‐established apricot orchards in the Central Otago region of South Island, New Zealand.

Two aspects of the results are surprising. The first is the relatively low levels of copper in the soil when compared with results from another orchard in the region. That orchard is 18 years old and mean soil copper has already reached 100.0 μg/g, indicating a much faster rate of accumulation than in the two orchards in the current study. The second unexpected result is that the younger orchard has a significantly higher level of copper than the older orchard. Reasons for these findings are discussed in relation to apparent differences in soil properties.  相似文献   
5.
章迎庆 《华中建筑》2007,25(10):11-12,24
以数字技术为先导的数字时代对城市空间形态和意识文化等诸多方面产生了巨大的影响,文化建筑空间在这个大背景下也相应转变,该文从休闲的视野对这种转变作了一些的探讨,希望以此能对当今文化建筑空间设计产生积极意义.  相似文献   
6.
通过对南方红壤山边沟果园套种日本草适应性的研究,发现新开山边沟果园4月套种日本草扦插苗当年的6月分萌数可达6条,8月可达16条,第二年的7月能达11.4条;当年6月干草量可达5 308 kg/hm2,8月达8 523 kg/hm2,比套种百喜草分别低2.61%、13.78%,种植第二年7月达17 333 kg/hm2,比百喜草增加8.33%;当年6月草层厚度可达25 cm,比百喜草低19.35%,当年8月达49 cm,种植第二年7月达46 cm,分别比百喜草高6.52%、2.2%;当年6月覆盖率可达55%,比百喜草低15.38%,当年8月达100%,比百喜草高2.04%,种植第二年7月与百喜草一样达100%;套种日本草当年土壤流失率比裸地减少79.41%,同时能有效改善果园的生态环境.  相似文献   
7.
闲暇教育是向大学生传授各种闲暇活动的知识和技能,提高其全面发展水平;校园媒体是高校校园文化建设的重要阵地和校园舆论中心。校园媒体凭借其高校意识形态引领者的地位可在大学生闲暇教育中充分发挥其媒介传播、舆论引导、理论宣教、推动组织的作用,对提升闲暇教育质量起到至关重要的作用。  相似文献   
8.
Changes in soil pH, exchangeable aluminium (Al), calcium (Ca), magnesium (Mg), and potassium (K) and extractable manganese (Mn) were investigated after urea fertigation of a sandy loam soil in an apple orchard in New Zealand. Urea at three rates (0, 25, 50 kg N ha–1 yr–1 or 0, 16.9, 33.8 g N emitter–1 yr–1) was applied in 4 equal fertigations. Soil cores at 4 profile depths (0–10, 10–20, 20–40 and 40–60 cm) directly below and 20 cm from the emitter were sampled approximately 4 weeks after each fertigation and in the following winter. Results obtained showed that the largest changes in soil pH and cations occurred in soils directly below the emitter in the 50 kg N ha–1 yr–1 treatment where the soil pH decreased by 1.6 pH units at all soil depths. The lowest pH of 4.3 was observed at a depth of 27 cm. Exchangeable Al and extractable Mn levels increased to 11 meq kg–1 and 78µg g–1 respectively. Estimated losses of Ca, Mg and K from the upper soil profile depth (0–10 cm) represented 23, 63 and 27% of their respective total exchangeable levels. At lower profile depths (>20 cm), accumulation of displaced K was evident. Variable, and generally non-significant, chemical changes recorded in soils 20 cm from the emitter were attributed to restricted lateral water movement, and therefore urea movement, down the profile.The present study showed that one season of urea fertigation by trickle emitters, applied to a sandy loam, at half the rate conventionally applied to apple orchards (50 kg N ha–1 yr–1) resulted in pH and mineral element imbalances which were potentially and sufficiently severe to inhibit tree growth.  相似文献   
9.
户外家具作为2l世纪家具界的新宠,体现着人们休闲放松的生活理想,顺应了国际发展趋势。国外对户外家具的研究开展的早,并已取得大量研究成果,我国还存在着较大的差距。但通过调查和分析,发现我国户外家具有许多发展动力优势,因此同样有巨大的发展潜力和好的应用前景。  相似文献   
10.
本文提出一种沼液水肥一体化防堵塞灌溉系统,并在新余市罗坊沼气站的蜜桔园进行推广应用。结果表明:在经过较长时间运行后流量未见明显损失,仍能保持原有效率,沼液过滤系统能够很好地将大中小固体颗粒除去,不易堵塞,保证处理后沼液满足作物正常生长使用。采用沼液水肥一体化防堵塞灌溉系统每亩平均减少肥料量50%,每亩产量平均增产2.8%,节本增收的经济效益平均每亩可达245.5元,经济效益显著,该沼液水肥一体化防堵塞灌溉系统适宜在南方果园推广应用。  相似文献   
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