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1.
Artigo em Inglês | MEDLINE | ID: mdl-38669013

RESUMO

2-Butanone peroxide (also known as methyl ethyl ketone peroxide, MEKP) has applications as a cross-linker in the chemical industry and is also encountered as a homemade primary high explosive; therefore, it is of interest to both process chemists and forensic examiners. Specifically for forensic applications, we demonstrate that when traditional synthetic procedures, available to any hobbyist, are utilized to generate MEKP, oligomeric peroxide units (n ≤ 12), along with several other oligomeric byproduct distributions, are readily observed by liquid chromatography-mass spectrometry (LC-MS). These oligomeric byproducts correspond to the formation of methyl/ethyl ketone end group(s) at the oligomer end group (i.e., loss of ethanol(s) and/or methanol(s) from the oligomer termini). Based on the interpretation of the MS and MS/MS behavior along with the characterization of newly generated terminal alkyl ketone products, we propose that these byproducts are consistent with a Hock-like rearrangement of the primary MEKP distribution in the acidified reaction medium. Following a procedure for homemade preparation, triplicate lots were synthesized. Unique oligomeric and byproduct distributions provided discriminatory power between the synthetic lots. Furthermore, the distributions of MEKP oligomers and the various byproducts in the initiated MEKP match the intensity distributions observed in the intact material with remarkable accuracy. This observation suggests that the postinitiation residue of MEKP could be associated or dissociated from a separately collected intact material obtained during an investigation by examining these oligomeric and byproduct profiles.

3.
J Adolesc Health ; 61(4): 454-460, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28712596

RESUMO

PURPOSE: The purpose of the study was to identify factors associated with uptake of contraceptive implants or intrauterine devices (IUDs) by adolescents and young women. METHODS: For this prospective cohort study, we recruited English-speaking female contraceptive initiators aged 14-24 years attending a Title X-supported, youth-focused clinic. Immediately prior to their visits, participants completed surveys assessing demographic and reproductive characteristics and awareness of, interest in, and intent to initiate specific contraceptive methods. Participants also answered questions about their social contacts' contraceptive experiences. Following the visit, participants reported the method initiated and the perceived importance of provider counseling. We used a multivariable regression model to ascertain factors associated with initiation of an IUD, an implant, or a short-acting reversible method. RESULTS: We enrolled 1,048 contraceptive initiators: 277 initiated short-acting methods, 384 IUDs, and 387 implants. High previsit personal acceptability of the method was associated with choosing that method for both implants and IUDs. Knowing someone who uses a specific method and likes it was predictive of personal acceptability of that method (IUD adjusted odds ratio: 10.9, 95% confidence interval: 3.8-31.1; implant adjusted odds ratio: 7.0, 95% confidence interval: 2.3-21.0). However, 10.4% of those initiating IUDs and 14.2% of those initiating implants had never heard of the method before their appointment. Even women with previsit intent to initiate a specific method found importance in contraceptive counseling. CONCLUSIONS: Previsit personal acceptability, which was associated with social contacts' experiences, was the strongest predictor of specific method uptake in our study. However, counseling informed the decisions of those with low previsit awareness and supported patients with formed intent.


Assuntos
Comportamento de Escolha , Anticoncepção/métodos , Anticoncepcionais Femininos/administração & dosagem , Dispositivos Intrauterinos , Adolescente , Adulto , Implantes de Medicamento , Serviços de Planejamento Familiar/métodos , Feminino , Humanos , Análise Multivariada , Estudos Prospectivos , Inquéritos e Questionários
4.
Genome Announc ; 4(4)2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27389265

RESUMO

Gordonia bacteriophage Yvonnetastic was isolated from soil in Pittsburgh, PA, using Gordonia terrae 3612 as a host. Yvonnetastic has siphoviral morphology and a genome of 98,136 bp, with 198 predicted protein-coding genes and five tRNA genes. Yvonnetastic does not share substantial sequence similarity with other sequenced bacteriophage genomes.

5.
J Sch Psychol ; 49(4): 411-31, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21723998

RESUMO

This study's primary goal was to evaluate the use of performance feedback procedures delivered to a classroom team to increase daily data collection. Performance feedback (PFB) was delivered to four classroom teams responsible for the daily collection of data representing student performance during prescribed instructional activities. Using a multiple-baseline design, the effects of the team performance-feedback were evaluated for the target student, and for generalization to data collection for all classroom students. A secondary question evaluated if student on-task behavior correlated with increased data collection. Finally, social validity was investigated to evaluate team satisfaction with the PFB intervention. The results demonstrate improved data collection across all four classroom teams for the target student in each classroom and generalization within classrooms to all remaining students. Slight increases in student on-task behavior were observed in three of the four classrooms, and teacher satisfaction ratings were high.


Assuntos
Retroalimentação Psicológica , Processos Grupais , Instituições Acadêmicas , Estudantes , Pré-Escolar , Coleta de Dados , Feminino , Humanos , Masculino
6.
J Biol Chem ; 282(46): 33743-33751, 2007 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-17878171

RESUMO

A gradient of Ran.GTP typically regulates traffic through the nuclear pore by modulating association of receptors with cargo. However, here we demonstrate that the yeast high mobility group box transcription factor Nhp6Ap enters the nucleus via a novel nuclear localization signal recognized by calcium calmodulin in a process that does not require Ran. Calmodulin is strictly required for the nondiffusional nuclear entry of Nhp6Ap. Calmodulin and DNA exhibit mutually exclusive binding to NHP6A, indicating that the directionality of Nhp6Ap nuclear accumulation may be driven by DNA-dependent dissociation of calmodulin. Our findings demonstrate that calmodulin can serve as a molecular switch triggering nuclear entry with subsequent dissociation of calmodulin binding upon interaction of cargo with chromatin. This pathway appears to be evolutionarily conserved; mammalian high mobility group box transcription factors often have two nuclear localization signals: one a classical Ran-dependent signal and a second that binds calmodulin. The finding that Nhp6Ap nuclear entry requires calmodulin but not Ran indicates that Nhp6Ap is a good model for studying this poorly understood but evolutionarily conserved calmodulin-dependent nuclear import pathway.


Assuntos
Calmodulina/metabolismo , Proteínas de Ligação a DNA/química , Proteínas Nucleares/química , Proteínas de Saccharomyces cerevisiae/química , Proteína ran de Ligação ao GTP/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Calmodulina/química , Bovinos , Cromatina/metabolismo , Sequência Conservada , DNA/química , Escherichia coli/metabolismo , Evolução Molecular , Proteínas Fúngicas/metabolismo , Proteínas de Fluorescência Verde/química , Proteínas HMGN , Modelos Biológicos , Conformação Molecular , Ligação Proteica , Transcrição Gênica
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