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Background: The use of social media has been growing rapidly with easy access for young people. Psychologists have studied the social and psychological impact of social media use on adolescents; however there is very little qualitative data of social media use among adolescents and their views.Aims: To explore the views of adolescents in Sussex about the educational, social and psychological impacts of using social media sites and analyze adolescents’ descriptions of their own personal experiences of social media use.Method: 500 young people between the ages of 11 to 18 years in Sussex (UK) were invited to take part in a questionnaire survey exploring their use and views about social media.Results: A total of 465 (93%) of students completed the questionnaire. 73% of participants used three or more sites. On average each participant spent 22 hours weekly on social media sites. In all five domains explored, the majority of participants scored the negative impact of use of social media as low with an overall mean of 2 out of possible 5. Over 70% scored low negative impact for Education, 75% for relationships, 64% for Self-esteem, 73% for Health and 71% for Safety. On the other hand, the percentage scoring 4 or 5 for positive impact were 22% for Education, 36% for Relationships, 24% for Self-esteem, 12% for Health and 15% for Safety. However there was a difference between younger and older teens.Conclusion: Studies have shown negative social media impact on teens including self-esteem, anxiety and depression. However young people have a different view. Young people have balanced views about the effects of social media. They felt that social media use improved their relationships, particularly among younger students. Older teens perceived higher negative effect on their safety. Further work is needed to improve the safety awareness of young teens.

A growing number of studies are revealing that many Milky Way globular clusters possess extended stellar structures beyond their traditional boundaries. Just how ubiquitous these structures are, and how they originate, are key questions to explore. In this contribution, we present a Bayesian technique that we have developed to separate probable members of globular clusters from the dominant Milky Way fore/background at large clustercentric radii and hence facilitate quantitative analyses of these intriguing structures. We demonstrate the promise of our method by showing how it recovers the known extended features around Palomar 5 and NGC 7089.

The thermal decomposition of the hexahydrate of samarium trichloride under an air atmosphere and under low pressure has been monitored through the use of ultraviolet–visible (UV-vis) diffuse reflection spectroscopy. The unique ability of lanthanide spectroscopy to investigate the near environment surrounding the samarium ion allowed for the identification of the hexa-, penta-, tetra-, tri-, di-, and monohydrates in both cases, as well as the formation of samarium oxychloride formed as the final decomposition product. The decomposition temperatures and the products observed in this report are compared to those obtained by other thermal and iso-thermal analyses of this compound, as well as the analogous decomposition of europium trichloride hexahydrate. Structural and environmental variations associated with the compounds, as indicated by the reflectance spectra, are discussed.

Multiaxial knitted non-crimp fabrics (NCFs) are a relatively new form of reinforcement for composites. A study focusing on the mechanical properties of such composites has been carried out and the results are reported in this paper. E-glass/epoxy composites were manufactured by the Resin Transfer Molding (RIM) process using different NCFs. The composites were tested in uniaxial tension, three point bending, compression and short beam shear. Results on elastic modulus and strength were obtained and compared among the different testing conditions. Failure of the NCF composites was examined visually after the final failure of the specimens. The test results on tension and flexural moduli were compared with Classical Lamination Theory (CLT) predictions, and good agreements were observed. The test results and inspections of failed specimens revealed that the NCF composite laminates behaved like their tape laminate counterparts. Consequently, low cost high perfomance composite laminates may be achieved through the use of NCF fabrics as reinforcing materials.

This study examined the influence of a 6-week gait retraining program on the knee adduction moment (KAM) and knee pain and function. Ten subjects with medial compartment knee osteoarthritis and self-reported knee pain participated in weekly gait retraining sessions over 6 weeks. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores and a 10-point visual-analog pain scale score were measured at baseline, post-training (end of 6 weeks), and 1 month after training ended. Gait retraining reduced the first peak KAM by 20% (p 0.01) post-training as a result of a 7° decrease in foot progression angle (i.e., increased internal foot rotation), compared to baseline (p 0.01). WOMAC pain and function scores were improved at post-training by 29% and 32%, respectively (p 0.05) and visual-analog pain scale scores improved by two points (p 0.05). Changes in WOMAC pain and function were approximately 75% larger than the expected placebo effect (p 0.05). Changes in KAM, foot progression angle, WOMAC pain and function, and visual-analog pain score were retained 1 month after the end of the 6-week training period (p 0.05). These results show that a 6-week gait retraining program can reduce the KAM and improve symptoms for individuals with medial compartment knee osteoarthritis and knee pain.

A series of trifluoromethyl-containing analogs of captopril as well as analogs and homologs of enalaprilat were synthesized and evaluated for inhibition of angiotensin converting enzyme (ACE). It was found that direct substitution of trifluoromethyl for methyl produced a very potent captopril analog with an IC50 of 3 x 10(-10) M in vitro. Hydrophobicity and conformational effects of trifluoromethyl group are among the reasons accounting for this activity. Structure-activity relationship is studied based on molecular mechanics calculations using a II-SCF-molecular mechanics program (PIMM) as well as SYBYL molecular mechanics program. It was found that simultaneous incorporation of trifluoromethyl and an indoline residue unexpectedly yielded a less potent captopril analog (IC50 = 8 x 10(-8) M). Enalaprilat analogs derived from replacement of the alanine residue with trifluoronorvaline and trifluoronorleucine residues gave moderately potent compounds (IC50 = 2-6 x 10(-8) M). The structure-activity relationship for these fluoroenalaprilat analogs is discussed in comparison with known analogs.