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51.
ObjectiveTo replicate the Dual Pathway Model (DPM) of bulimia nervosa (BN) symptoms prospectively, and to assess whether a revised version of the DPM that included the variables social comparisons made on Facebook and sociotropy influenced the DPM.MethodParticipants were 245 females who completed baseline measures (T1) that assessed the DPM, as well as the constructs social comparisons made on Facebook, and sociotropy, and a follow-up questionnaire, which assessed symptoms of depression, bulimia, and dietary restraint, one month later (T2).ResultsPath analysis revealed that the original and the revised DPMs had excellent fit once modifications to the respective models were made. In both DPMs, T1 pressures to be thin and T1 thin ideal internalization were related to T1 body dissatisfaction. T1 body dissatisfaction prospectively predicted T2 depressive symptoms and T2 bulimic symptoms, but not T2 dietary restraint. Furthermore, T2 dietary restraint, but not T2 depressive symptoms, predicted T2 BN symptoms. Results also showed that T2 dietary restraint was associated with T2 depressive symptoms. In the revised DPM, T1 social comparisons made on Facebook were associated with T1 body dissatisfaction, T1 pressures to be thin, and T2 bulimic symptoms. T1 sociotropy was related to T1 social comparisons on Facebook, T1 pressures to be thin, T1 body dissatisfaction, and T2 bulimic symptoms.ConclusionsFindings suggest the BN preventative efforts might benefit from addressing appropriate forms of social comparisons, especially those made on Facebook, and the personality trait sociotropy. 相似文献
52.
Depression is one of the most common mental disorders. Studies have shown that various online social network (OSN) activities can be used as a marker for people's moods as well as symptoms of subsyndromal depression, suggesting possibilities for online-based interventions. This study investigates one such potential by developing an expressive writing application within Facebook and by investigating how the designed intervention as well as various online social network activities contribute to improving one's emotional state. Experimental data show that negative emotional words and cognitive words in online expressive writing are the two most important factors in alleviating depressive symptoms. Furthermore, participants who have had previous experience expressing emotions in OSNs reported the greatest reduction in depressive symptoms. Our findings have implications that can assist in designing personalized online intervention platforms and for sophisticated writing therapy to maximize the effect of expressive writing. 相似文献
53.
松辽盆地徐家围子断陷沙河子组储层特征及控制因素 总被引:1,自引:0,他引:1
徐家围子断陷沙河子组是松辽盆地北部近期天然气勘探的主要目标,这类致密砂砾岩气层的储层特征及控制因素研究是首要的。通过分析其白垩系早期拉张构造背景条件下形成的一套断陷沉积,纵向上可划分为4个三级层序,各层序在断陷湖盆陡坡带和缓坡带发育扇三角洲和辫状河三角洲沉积。研究表明其储层主要为砂砾岩和含砾粗砂岩等粗碎屑岩。沙河子组储层孔隙包括原生粒间孔和次生孔隙,孔隙度主要分布在2%~8%,渗透率多小于0.1×10-3 μm2,为致密储层。沙河子组储层发育的控制因素包括埋深、沉积相带、岩石类型和次生成岩作用,埋藏浅的扇三角洲(辫状河三角洲)前缘、平原相砂砾岩储层物性好,含火山碎屑物质的砂岩、砂砾岩易于形成溶蚀孔隙,改善储集性能。徐家围子断陷沙河子组有利储层主要位于埋深小于4 000 m的安达东、西两侧的扇三角洲前缘、平原区和徐东、徐西的构造高部位扇体发育区,埋藏较浅的安达中部滨浅湖相和埋藏较深的徐东、徐西斜坡扇体发育区也是较有利的储层发育区。 相似文献
54.
Internet use and depression among older adults 总被引:2,自引:0,他引:2
The findings regarding the impact of Internet use on well-being are mixed and studies are often criticized due to small samples and lack of consistency in measurement. Fewer studies have examined this issue among older adults. The purpose of this study is to examine the relationship between Internet use and depression among retired Americans age 50 years or older. Using data from the Health and Retirement Survey, the study estimates the relationship between Internet use and depression through combined use of regression and propensity score methodologies. All empirical methods indicate a positive contribution of Internet use to mental well-being of retired older adults (?50 years), reducing depression categorization by approximately 20–28%. 相似文献
55.
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57.
THE NATURE AND ORIGIN OF AUTHIGENIC CHLORITE AND RELATED CEMENTS IN OLIGO–MIOCENE RESERVOIR SANDSTONES,TAPTI GAS FIELDS,SURAT DEPRESSION,OFFSHORE WESTERN INDIA 下载免费PDF全文
J. M. Huggett S.D. Burley F. J. Longstaffe S. Saha M. J. Oates 《Journal of Petroleum Geology》2015,38(4):383-409
Reservoir sandstones in the Mid‐ and South Tapti gas fields in the Surat Depression (Mumbai Offshore Basin, western India) have been investigated using a range of petrographic techniques, isotope geochemistry and basin modelling. Authigenic chlorite is abundant in the shallow‐marine sandstones of the Miocene Mahim Formation, a major reservoir rock in the Mid‐ and South Tapti fields, which are described here in terms of their quality and diagenetic characteristics. The sandstones are currently at burial depths of between ~1500 and 2800m. The authigenic chlorite has had a significant impact on the resulting reservoir quality of the sandstones and is interpreted to have originated as odinite clay of the verdine facies that replaced faecal or pseudo‐faecal pellets, together with volumetrically small but abundant grain coatings and grain rims, and formed at the site of major riverine iron influx onto the shallow‐marine shelf during periods of relatively low sea level. Pellets have been variably compacted to form pseudomatrix. Reservoir sandstones from similar depositional settings on the west coast of India or other sub‐tropical settings are likely to exhibit comparable diagenetic effects on reservoir quality. Compositionally, the chlorite is the iron‐rich form known as chamosite. The chemistry of all the chlorite morphologies is the same in all studied samples. Oxygen isotope analyses of carbonate cements in the Mahim Formation sandstones have provided an approximate temperature framework for diagenesis of the non‐carbonate cements. Oxygen isotope results for the chlorite, however, suggest much higher temperatures than its position in the paragenetic sequence would warrant. These results suggest that the clay formed first as 1:1 layer clays, in this case odinite, which were then transformed to Fe‐chlorite as burial depths and temperatures increased. Reservoirs in the Mahim, Daman and Mahuva Formation sandstones are thus greatly influenced by the diagenesis of authigenic chlorite and locally by the precipitation of carbonate cements. Reservoir quality is good where thick, continuous chlorite rim cements are present and where chlorite pellets are sufficiently indurated for them not to be compacted. Chlorite rim cements have reduced the extent of quartz overgrowth cementation in the sandstones. 相似文献
58.
歧口凹陷歧北低斜坡B90井区,油气藏发育广泛,沙一下是该区勘探开发的重点。对研究区,沙一下油藏基本特征进行研究,分析其成藏条件,从而指导油气勘探。研究区油藏类型可分为构造-岩性油藏及岩性油气藏两种。研究区地层埋深较大,烃源岩成熟,生烃条件良好、源储一体,油气运移动力强。在运聚方向上的上倾尖灭砂体捕获油气而成藏。研究认为,B90井区,连接歧南、歧北斜坡,砂体叠置发育,连片分布,物性好,形成岩性上倾尖灭的岩性圈闭。这种岩性圈闭厚度大、条件好产量高,是大港油田重要的增储上产地区。 相似文献
59.
青东凹陷具有独特而复杂的成藏特征,通过基础地质的综合研究,识别出青东凹陷发育构造、地层、岩性和复合油藏等四类油藏类型,阐述了各种不同油藏类型的分布特征;通过典型油气藏解剖,明确了有效烃源岩、储盖组合、油气输导条件等油气成藏要素和主控因素,研究认为青东凹陷具有双源供烃的油源条件,发育6套储盖组合,骨架砂体和输导断层为油气运移的有效通道;将青东凹陷划分为西北部斜坡、西南部断阶、中部深洼和东部走滑断裂四个油气聚集带,并解剖了各个油气聚集带的成藏类型及成藏主控因素。 相似文献
60.
东濮凹陷地质三分性与沙三期沉积古地理 总被引:1,自引:0,他引:1
东濮凹陷构造与沉积明显分为2个阶段:沙三段沉积时期和沙二段-东营组沉积时期。沙三段时期,东濮地区发育濮阳湖和东明湖。濮阳湖受兰聊、五星集-六塔断层活动控制,形成深水湖相-浅水盐湖相的暗色泥岩与盐岩、砂岩韵律,是现今油气最丰富的领域,盆内二级断层——杜寨断层、石家集-马寨断层、濮西断层的相继发育控制沉积中心的分布;东明湖是受兰聊断层活动控制的箕状凹陷,因补偿速度快,仅形成浅一半深水的砂泥岩韵律,生油岩发育质量差,现今的西洼南部地区是上述两湖泊的边缘,基本无生油岩发育。沙二段-东营组时期,长垣、黄河、文东、文西等断层强烈活动,形成两洼-隆一斜坡的构造格局,彻底改变了沙三期的沉积古地理,形成多个洼陷和多个沉积中心。 相似文献