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51.
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   
52.
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   
53.
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   
54.
In habitually shod recreational runners, we studied the combined influence of footwear and stretch-shortening cycle (SSC) fatigue on treadmill running pattern, paying special attention to neuro-mechanical adjustments in the acute and 2-day delayed recovery periods. The SSC exercise consisted of a series of 25 sub-maximal rebounds on a sledge apparatus repeated until exhaustion. The acute and delayed functional fatigue effects were quantified in a maximal drop jump test. The neuro-mechanical adjustments to fatigue were examined during two submaximal treadmill run tests of 3 min performed either barefoot or with shoes on. Surface electromyographic (EMG) activities, tibial accelerations and kinematics of the right lower limb were recorded during the first and last 15 s of each run. The main result was that neuro-mechanical differences between the shod and barefoot running patterns, classically reported in the absence of fatigue, persisted in the fatigued state. However, in the delayed recovery phase, rearfoot eversion was found to significantly increase in the shod condition. This specific footwear effect is considered as a potential risk factor of overuse injuries in longer runs. Therefore, specific care should be addressed in the delayed recovery phase of SSC fatigue and the use of motion control shoes could be of interest.  相似文献   
55.
We read with interest the authors’ paper on this important area of climbing physiology. We however wish to highlight the incorrect identification of flexor carpi radialis (FCR) as a finger flexor and the implications it has for the conclusions described. FCR is a wrist flexor and has no direct bearing on flexion of the fingers during a climbing grip and thus could be expected to have a reduced oxygenation response compared to flexor digitorum profundus. We also would like to seek clarification from the authors regarding their confidence in their method for locating the two muscles under investigation as we feel this may not be accurately possible using the method described.  相似文献   
56.
The aim of this study was to investigate how the type of contact influences physiological, perceptual and locomotive load during a simulated rugby league match. Eleven male university rugby league players performed two trials of the rugby league movement simulation protocol for interchange forwards with a traditional soft tackle bag and a weighted tackle sled to replicate contact demands. The interchange forward-specific simulation was chosen given the contact frequency is higher for this group of players compared to whole match players. Locomotive rate, sprint speed, tackle intensity, heart rate (HR) and rating of perceived exertion were analysed during the first and second bouts that replicated two ~23 min on-field passages. Countermovement jump (CMJ) was measured before and immediately after each trial. More time was spent in heart rate zone between 91 and 100% HRpeak during the first (effect size ± 90% confidence interval: 0.44 ± 0.49) and second bouts (0.44 ± 0.43), and larger (0.6 ± 0.69) decrements in CMJ performance were observed during the sled trial (5.9, = 4.9%) compared to the bag trial (2.6, = 5.4%). Changing the type of contact during the match simulation subtly altered both the internal and external loads on participants. Using a standard tackle bag results in faster sprint speed to contact, but lower overall high-intensity running. Conversely, a heavier tackle object increases the internal load and results in greater lower limb neuromuscular fatigue as reflected by the decrease in CMJ performance.  相似文献   
57.
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   
58.
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   
59.
60.
Purpose: The purpose of this study was to investigate whether loads carried in a backpack, with a load mass ranging from 0 to 20?kg, causes respiratory muscle fatigue. Methods: Eight males performed four randomised load carriage (LC) trials comprising 60?min walking at 6.5?km?h?1 wearing a backpack of either 0 (LC0), 10 (LC10), 15 (LC15) or 20?kg (LC20). Inspiratory (PImax) and expiratory (PEmax) mouth pressures were assessed prior to and immediately following each trial. Pulmonary gas exchange, heart rate (HR), blood lactate and glucose concentration and perceptual responses were recorded during the first and final 60?s of each trial. Results: Group mean PImax and PEmax were unchanged following 60-min load carriage in all conditions (p?>?.05). There was an increase over time in pulmonary gas exchange, HR and perceptions of effort relative to baseline measures during each trial (p?p?>?.05). Conclusions: These findings indicate that sub-maximal walking with no load or carrying 10, 15 or 20?kg in a backpack for up to 60?min does not cause respiratory muscle fatigue despite causing an increase in physiological, metabolic and perceptual parameters.  相似文献   
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