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151.
ABSTRACT

This study compares the interactional practices for the main types of uses of the mobile dating applications Grindr and Tinder. The analysis shows that in both cases, a majority of users share a similar orientation towards a linguistic ideology regarding ordinary conversation as a social institution, as topic-based, as allowing individuals to share and update knowledge so as to enable rapport and intimacy. However, Grindr and Tinder users take almost opposite conversational stances regarding the organization of casual hookups as sexual, one-off encounters with strangers. While many gay Grindr users have to chat to organize quick sexual connections, they become wary of the way their electronic conversations might waylay them into more personal relationships and they try to prevent this by developing an interactional genre made of laconic, fact-checking and very short exchanges. On the other hand, many heterosexual users on Tinder are looking to achieve topically-rich chat conversations. Their interactional dilemma, then, is the achievement of such topically-rich conversation, but with complete strangers. The interaction-oriented comparison provides a more detailed and subtle perspective of the alleged ‘liquefaction’ of romantic relationships into a casual hookup culture through the use of location-aware mobile dating applications.  相似文献   
152.
To characterize hypertrophy and quantify seasonal changes in cardiac structure and function of women collegiate basketball (BB) athletes (n = 15), echocardiographic (echo) measurements were made in the fall (FALL1), winter (WIN), and spring (SPR), then again during the subsequent fall (FALL2; n = 10). Comparisons were made to age-matched nonathletes (NA) measured during FALL1 (n = 22) and SPR (n = 5). Left ventricular (LV) internal dimension-diastole (LVIDd), LV end-diastolic volume (LVEDV), stroke volume (SV), LV mass (LVM), septal thickness (IVS), LV posterior wall thickness (LVPW), right ventricular (RV) internal dimension-diastole (RVIDd), and aortic root diameter (AOD) were significantly larger (12-70%) in the athletes; RVIDd-, LVEDV-, SV-, and LVM-index were also significantly greater (8-46%). From FALL1 to SPR measurement periods, LVIDd, RVIDd, LVEDV, SV, IVS, and LVM-index increased significantly (7-18%) in the athletes. Over the same period of time, LVIDd, LAD, AOD, LVEDV, and SV measured in the five NA subjects increased significantly. In the athletes, LVIDs, RVIDd, IVS, LVPW, and LVM decreased significantly (5-30%) from the SPR to FALL2 measurement period. These data characterize the general nature of the cardiac hypertrophy noted in women BB athletes compared to NA controls and show that distinct changes in heart structure corresponding to different periods of the competitive season can occur in these athletes.  相似文献   
153.
Zusammenfassung. Kollektionen wie Mengen, Listen und Felder spielen in objektorientierten Anwendungen und Datenbanken eine wichtige Rolle. Dementsprechend sollten sie zusammen mit anderen objektrelationalen Konzepten auch in die aktuelle Datenbanknorm SQL:1999 eingebracht werden. Aus Aufwands- und Zeitgründen wurden jedoch vom Normungsgremium, zu dem auch die Vertreter wichtiger Hersteller kommerzieller (objekt-)relationaler Datenbankmanagementsysteme gehören, zunächst nur Felder (Arrays) berücksichtigt; andere Kollektionsarten sollen erst später folgen. Auch in wichtigen DBMS-Produkten werden Kollektionen bislang nur unzureichend und auf heterogene Art und Weise unterstützt. Dieser Beitrag beschäftigt sich mit den Möglichkeiten einer Ergänzung von SQL:1999 um wichtige Kollektionsarten. Basierend auf dem aktuellen Stand von Norm und Produkten werden prinzipielle Fragen der Integration in SQL diskutiert und die Grundlagen einer adäquaten Unterstützung von Kollektionen erörtert. Der formale Sprachvorschlag auf Basis von SQL:1999 kann hier aus Platzgründen nicht näher vorgestellt werden, einige Beispiele sollen aber die Anwendung der neuen Modellierungsmöglichkeiten verdeutlichen. Eingegangen am 15. Februar 2002/Angenommen am 10. September 2002CR Subject Classification H.2.1, H.2.3, H.2.4, D.3.3  相似文献   
154.
Discoloured 18-carat gold decorations from Sweden have been analysed by scanning electron microscopy with energy dispersive X-ray spectroscopy and X-ray electron spectroscopy (XPS)/electron spectroscopy for chemical analysis (electron spectroscopy).The original gold composition was close to 75% gold, 13% silver, and 12% copper. After manufacture, many details were boiled in sulphuric acid. As a consequence of this, the surfaces are irregular and porous with a gold concentration around 90% and with less than 1% copper. With XPS the outermost 10–20 atomic layers could be examined. No copper was present here, and the silver concentration was significantly higher. Also carbon, sulphur, oxygen, and (in one case) chlorine were present. The valence numbers indicated that gold only occurred in its metallic state, while silver (as Ag+) was preferably associated with sulphur to form black silver sulphide (Ag2S). The grey discolorations are basically due to silver sulphide and organic dirt. Sometimes green, violet, and ‘copper-shining’ colours occur, presumably as a result of light refraction phenomena.  相似文献   
155.
Abstract

This paper concludes that a number of different discourses marked the coverage of Danish–German sports collaboration during the Second World War in German newspapers, sports magazines and newsreels. From the outbreak of the Second World War to the German occupation of Denmark on 9 April 1940, the discourses cover neutrality and friendship with Germany. After the invasion of Denmark, a discourse of Nordic sentiments became very important in the communications of the press, with Danish athletes portrayed as Nordic citizens, which some circles of German society could interpret as a euphemism for the Nazi idea of a strong Aryan Scandinavia. During the autumn of 1941, the rising strain on Germany’s resources made the sports media a supplier of success. The discourse of a strong Germany replaced the previous discourses. As German–Danish sporting events ceased in 1942, Danish sport alone would still make occasional appearances in the German media until 1944, providing a German audience with entertainment and distraction.  相似文献   
156.
This article aims to provide an overview of the current state of research on the relationship between loneliness and physical activity (PA). A systematic literature search was conducted to identify all empirical studies assessing this relationship. A total of 37 studies stemming from 36 publications met the inclusion criteria. Study analyses comprised an individual consideration of each study and a systematic summarization of the studies. The majority of eligible studies focused on adolescent or elderly populations. Direct negative associations between PA and loneliness were found in half of the 24 cross-sectional studies. Of the seven identified longitudinal studies, one found a direct negative influence of PA on loneliness. Four longitudinal studies found evidence for a reverse influence, namely of loneliness on PA. Five intervention studies found PA to reduce loneliness. Two of the cross-sectional studies and one of the intervention studies found social support and social competence to moderate or to mediate the relationship between PA and loneliness. The findings indicate that PA can contribute to a decrease in loneliness. However, studies also indicate that any beneficial effect is dependent upon the quality of relationships present during physical activity. Additionally, loneliness itself might reduce the probability of being physically active.  相似文献   
157.
158.
Assessment reform, in particular a move towards more school‐based forms of assessment, has become a global phenomenon. Involving teachers more centrally in assessment has often been rationalised by claims derived from the literature on formative assessment, hinging on the enhanced validity of performance assessment and the potential of classroom assessment for improving the quality of learning. This paper draws on work in Ghana and England which suggests that in neither case are the potentialities for improvement being realised. Teachers’ conceptualisation of assessment has been a significant barrier to improvement. We present outlines of participatory research projects to address this problem, where practitioners’ own investigation will be used as a way of addressing the need for changes, rooted both in increased technical expertise and in their own belief systems. The divergent contexts for the projects may enable a deeper evaluation of the potential of this methodology than might have occurred in just one country.  相似文献   
159.
<正>Marine carbonates, such as sedimentary carbonates and secondary carbonates formed during marine alteration processes, are returned to the mantle at subduction zones, and their fates regulate the global carbon cycle. Some carbonates are destroyed at the subduction zones,  相似文献   
160.
A practical reinforcement hierarchy was proposed for classroom-based behavior modification programs. The seven-level hierarchy ranged from primitive consequences (Le., Infantile Physical Contact and Food) through the more abstract consequences (i.e., Praise and Internal Self-Reinforcement). Suggestions were made for using the hierarchy in teacher consultation and behavior modification planning.  相似文献   
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