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31.
This study examined how communal coping reveals itself in Palestinian refugee camps and the conditions that promote or prevent its occurrence. Individual and dyadic interviews were conducted with 40 mothers and one of their adolescent children living in Palestinian refugee camps in Lebanon. The results revealed that communal coping existed within the mother–adolescent dyad to a certain extent, but was rare within the larger context of the refugee camps. While families and neighbors did not typically verbalize their hardships and actively cope with them as a group, there was often an implicit recognition that they were all experiencing the same uncertainty and stress. Acting upon their uncertainty as a collective, however, was greatly hampered by mistrust within and outside the camps, due to widespread violence, privacy violations, vying for scarce resources, and disloyalty. Parents and adolescents also engaged in protective buffering whereby they attempted to reduce the stress of the family by keeping stress and fears to themselves rather than communicating about them. Even though protective buffering helped the refugees cope with chronic uncertainty and maintain a sense of normalcy, it prevented them from acting upon the problem as a group. Finally, parents emphasized that the child’s education provided hope for the future. Practical implications are discussed.  相似文献   
32.
西部大开发战略的提出标志着我国经济发展战略的重大转变,也是实现经济均衡发展的重要举措,如何实现西部经济快速起飞,关键在于实现三个转变:经济发展战略从“梯度推移论”到西部跳跃发展;经济发展环境从偏向沿海地区向西部地区转移;经济发展重点从城市偏向改革到注重农村市场开拓。  相似文献   
33.
对恢复高考英语听力测试的思考   总被引:2,自引:0,他引:2  
自2000年以来,我国开始在高考英语试题中逐渐推广听力测试,2003年高考英语听力测试在全国普及,促进了基础教育阶段学生英语听力水平的提高。但2005年起出现了部分省区取消或淡化高考英语听力的现象。本文探讨了此举的原因、危害,建议尽早恢复高考英语听力测试,发挥高考对基础英语教育的正面反拨作用,为培养学生的英语交际能力打下基础。  相似文献   
34.
First-rib stress fractures have been described in adolescent athletes in various sports, with only one prior case report of first-rib stress fractures in an adolescent female swimmer. There is a need for research on the cause, management, and prevention of these injuries as they lead to significant morbidity and critical time away from sport for these aspiring athletes. We aimed to describe first-rib stress fractures as a potential cause for non-specific atraumatic chronic shoulder pain in adolescent swimmers and to discuss the different presentations, unique risk factors, treatment, and potential injury prevention strategies of such fractures. We discussed two such cases which were successfully treated with activity modification with restriction of all overhead activity, gradually progressive physical therapy and a return to swimming protocol. First-rib stress fractures can vary in presentation and should be in the differential diagnosis in adolescent swimmers with chronic shoulder pain. These injuries can be successfully managed with rest from overhead activities and physical therapy. Gradual return to competitive swimming can be achieved even with non-union of a first-rib stress fracture. Emphasis on balanced strength training in different muscle groups and proper swimming technique is essential to prevent these injuries.  相似文献   
35.
The aim of this study was to evaluate the predictive potential provided by two ventilatory inflection points (VIP1 and VIP2) examined in field without using gas analysis systems and uncomfortable facemasks. A calibrated respiratory inductance plethysmograph (RIP) and a computerised routine were utilised, respectively, to derive ventilation and to detect VIP1 and VIP2 during a standardised field ramp test on a 400 m running track on 81 participants. In addition, average running speed of a competitive 1000 m run (S1k) was observed as criterion. The predictive value of running speed at VIP1 (SVIP1) and the speed range between VIP1 and VIP2 in relation to VIP2 (VIPSPAN) was analysed via regression analysis. VIPSPAN rather than running speed at VIP2 (SVIP2) was operationalised as a predictor to consider the covariance between SVIP1 and SVIP2. SVIP1 and VIPSPAN, respectively, provided 58.9% and 22.9% of explained variance in regard to S1k. Considering covariance, the timing of two ventilatory inflection points provides predictive value in regard to a competitive 1000 m run. This is the first study to apply computerised detection of ventilatory inflection points in a field setting independent on measurements of the respiratory gas exchange and without using any facemasks.  相似文献   
36.
低温胁迫下镧对水稻种子萌发的影响   总被引:3,自引:0,他引:3  
以水稻(Oryza sativa)种子为实验材料,研究了不同浓度稀土元素镧浸种对水稻种子低温萌发的影响。结果表明:15℃低温胁迫抑制水稻种子的萌发,浸种期用硝酸镧处理能够提高种子的抗逆性。低浓度((50~250)×10-6mol/L)硝酸镧浸种能提高水稻种子发芽率、发芽势、呼吸速率和过氧化氢酶活性,提高种子抗寒能力,实验发现用硝酸镧处理种子萌发以250×10-6mol/L浓度为最佳,低温胁迫下,发芽率提高9.67%,呼吸速率提高56.25%,过氧化氢酶活性提高1.73%。350×10-6mol/L以上高浓度对水稻种子的萌发无明显影响。  相似文献   
37.
This investigation examined the oxidative stress (F2-Isoprostane; F2-IsoP) and inflammatory (interleukin-6; IL-6) responses to repeat-sprint training in hypoxia (RSH). Ten trained male team sport athletes performed 3(sets)*9(repetitions)*5?s cycling sprints in simulated altitude (3000?m) and sea-level conditions. Mean and peak sprint power output (MPO and PPO) were recorded, and blood samples were collected pre-exercise, and again at 8 and 60?min post-exercise. Both MPO and PPO were significantly reduced in hypoxia (compared to sea-level) in the second (MPO: 855?±?89 vs. 739?±?95?W, p?=?.006; PPO: 1024?±?114 vs. 895?±?112?W, p?=?.010) and third (MPO: 819?±?105 vs. 686?±?83?W, p?=?.008; PPO: 985?±?125 vs. 834?±?99?W, p?=?.008) sets, respectively. IL-6 was significantly increased from pre- to 1?h post-exercise in both hypoxia (0.7?±?0.2 vs. 2.4?±?1.4?pg/mL, p?=?.004) and sea-level conditions (0.7?±?0.2 vs. 1.6?±?0.3?pg/mL, p?d?=?0.80) suggesting higher IL-6 levels of post-hypoxia. F2-IsoP was significantly lower 1?h post-exercise in both the hypoxic (p?=?.005) and sea-level (p?=?.002) conditions, with no differences between trials. While hypoxia can impact on exercise intensity and may result in greater post-exercise inflammation, it appears to have little effect on oxidative stress. These results indicate that team sport organisations with ready access to hypoxic training facilities could confidently administer RSH without significantly increasing the post-exercise inflammatory or oxidative stress response.  相似文献   
38.
通过对浙江省嘉兴、湖州两个地区部分中学的抽样调查,从教材和课时、教学设备、师资力量等多个方面分析我国中小学信息技术教育的现状.在分析过程中,除一般的对比说明外,还运用了Excel数理分析中的假设检验,对该学科在教学条件方面存在的问题做进一步揭示,并提出一些可行性建议.  相似文献   
39.
研究了水分胁迫下亚精胺对小麦幼苗相对含水量、叶绿素总量、蛋白质含量和蛋白酶活性的影响。结果显示,亚精胺预处理延缓水分胁迫下小麦幼苗叶片含水量、叶绿素含量和蛋白质含量的下降,抑制蛋白酶活性的上升。表明亚精胺预处理对水分胁迫的小麦幼苗具有防衰抗旱的保护作用。  相似文献   
40.
烟囱倾倒过程中,通过对横截面上切应力及拉伸(压缩)应力的计算,确定了倾倒时烟囱被破坏的主要力学原因及表现是,在外侧强大的拉应力作用下,烟囱从外侧开始被拉断.  相似文献   
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