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1.
Arch Sex Behav ; 50(6): 2347-2357, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33982213

RESUMO

This study examined the extent to which active and passive sexting behaviors are associated with family-, school-, peer-, and romantic-level variables. Young people (N = 3,322; 49.1% female, 48.3% male, 2.6% other) aged 11 to 15 years old (M = 12.84, SD = 0.89) took part, and all attended mainstream secondary schools in Scotland. Participants completed self-report measures of school connectedness, parental love and support, perceived susceptibility to peer- and romantic-pressure (e.g., to display behaviors just to impress others), and their involvement in active and passive sexting. The importance of both school- and family-level factors was evident, though perceived romantic-pressure had the largest effect. However, neither school- nor family-level variables were moderated by either perceived romantic-pressure or perceived peer-pressure. Efforts to reduce sexting or increase its safety should primarily seek to tackle young people's ability to respond effectively to romantic-pressure. It may also be helpful to develop school connectedness and to help families provide support that is constructive and not intrusive.


Assuntos
Comportamento do Adolescente , Envio de Mensagens de Texto , Adolescente , Feminino , Humanos , Masculino , Grupo Associado , Instituições Acadêmicas , Comportamento Sexual
2.
ChemistryOpen ; 8(12): 1375-1382, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31844604

RESUMO

Fentanyl, also known as 'jackpot', is a synthetic opiate that is 50-100 times more potent than morphine. Clandestine laboratories produce analogues of fentanyl, known as fentalogues to circumvent legislation regarding its production. Three pyridyl fentalogues were synthesized and then hyperpolarized by signal amplification by reversible exchange (SABRE) to appraise the forensic potential of the technique. A maximum enhancement of -168-fold at 1.4 T was recorded for the ortho pyridyl 1H nuclei. Studies of the activation parameters for the three fentalogues revealed that the ratio of ligand loss trans to hydride and hydride loss in the complex [Ir(IMes)(L)3(H)2]+ (IMes=1,3-bis(2,4,6-trimethylphenyl)imidazole-2-ylidene) ranged from 0.52 to 1.83. The fentalogue possessing the ratio closest to unity produced the largest enhancement subsequent to performing SABRE at earth's magnetic field. It was possible to hyperpolarize a pyridyl fentalogue selectively from a matrix that consisted largely of heroin (97 : 3 heroin:fentalogue) to validate the use of SABRE as a forensic tool.

3.
J Agric Food Chem ; 51(10): 3092-6, 2003 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-12720397

RESUMO

Aroma is central to a pleasurable eating/drinking experience but is one of the most labile components of food. Coffee is an outstanding example. Attempts to avoid or control aroma degradation are often frustrated by ignorance of the microscopic mechanisms that are responsible for it. One of the processes most frequently invoked is radical formation, yet the identity of the radicals and their involvement in aroma degradation are poorly understood at the molecular level. Here a step forward in the fundamental understanding of this complex problem is taken by identifying the most relevant radicals and their products using first-principles calculations. Over 100 radicals originating from key aroma compounds found in coffee and other foods have been studied and classified according to an unambiguous criterion: their thermodynamic stability relative to common radical sources. This classification scheme predicts that most aroma molecules are resistant to both peroxidation and attack from phenolic antioxidants but are unstable with respect to radicals such as .OH. Dimers--generated from radical reactions--were also considered, and the most volatile species, which may further contribute to coffee aroma degradation, were focused on. Those--which are very few indeed--that have this potential have been identified.


Assuntos
Café/química , Odorantes/análise , Estabilidade de Medicamentos , Radicais Livres/química , Estrutura Molecular , Fenóis/análise , Fenóis/química , Compostos de Sulfidrila/análise , Compostos de Sulfidrila/química , Termodinâmica , Volatilização
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