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1.
Life Sci Space Res (Amst) ; 17: 15-22, 2018 May.
Article de Anglais | MEDLINE | ID: mdl-29753409

RÉSUMÉ

If extraterrestrials exist in the depths of cosmic space, and are capable of interstellar communications, even space flight, there is no requirement that they be humanoid in form. However, certain humanoid capabilities would be advantageous for tool fashioning and critical to operating space craft as well as functioning under the disparate extreme conditions under which they may be forced to operate. They would have to be "gas breathing". The reasonable assumption that life based upon the same elements as Earth life requiring water stems from the unique properties of water that no other similar low molecular weight nonmetal hydride offers. Only water offers the diversity of chemical properties and reactivity, including the existence of the three common physical states within a limited temperature range of service to life, avoiding the issues presented by any alternatives. They must, like us, possess a large, abstract-thinking brain, and probably possess at least all the fundamental senses that humankind possess. They would also be carbon-based life, using oxygen as the electron sink of their biochemistry for the reasons considered. They most likely are homeothermic as us, though they may not necessarily be mammalian as we are. Their biochemistry could differ some from ours, perhaps presenting contact hazards for both species as discussed.


Sujet(s)
Évolution biologique , Environnement extraterrestre , Intelligence , Vie , Carbone/composition chimique , , Gaz/composition chimique , Humains , Phénotype , Eau/composition chimique
2.
Space Sci Rev ; 2142018.
Article de Anglais | MEDLINE | ID: mdl-33758433

RÉSUMÉ

The Ionospheric Connection Explorer, or ICON, is a new NASA Explorer mission that will explore the boundary between Earth and space to understand the physical connection between our world and our space environment. This connection is made in the ionosphere, which has long been known to exhibit variability associated with the sun and solar wind. However, it has been recognized in the 21st century that equally significant changes in ionospheric conditions are apparently associated with energy and momentum propagating upward from our own atmosphere. ICON's goal is to weigh the competing impacts of these two drivers as they influence our space environment. Here we describe the specific science objectives that address this goal, as well as the means by which they will be achieved. The instruments selected, the overall performance requirements of the science payload and the operational requirements are also described. ICON's development began in 2013 and the mission is on track for launch in 2017. ICON is developed and managed by the Space Sciences Laboratory at the University of California, Berkeley, with key contributions from several partner institutions.

3.
Virus Res ; 108(1-2): 1-14, 2005 Mar.
Article de Anglais | MEDLINE | ID: mdl-15681049

RÉSUMÉ

In this study we analysed the outcome of the interaction between HPV-16 L2 and E2 on the transactivation and DNA replication functions of E2. When E2 was expressed on its own, it transactivated a number of E2-responsive promoters but co-expression of L2 led to the down-regulation of the transcription transactivation activity of the E2 protein. This repression is not mediated by an increased degradation of the E2 protein. In contrast, the expression of L2 had no effect on the ability of E2 to activate DNA replication in association with the viral replication factor E1. Deletion mutagenesis identified L2 domains responsible for binding to E2 (first 50 N-terminus amino acid residues) and down-regulating its transactivation function (residues 301-400). The results demonstrate that L2 selectively inhibits the transcriptional activation property of E2 and that there is a direct interaction between the two proteins, although this is not sufficient to mediate the transcriptional repression. The consequences of the L2-E2 interaction for the viral life cycle are discussed.


Sujet(s)
Protéines de capside/métabolisme , Réplication de l'ADN , Protéines de liaison à l'ADN/métabolisme , Protéines des oncogènes viraux/métabolisme , Papillomaviridae/physiologie , Cartographie d'interactions entre protéines , Activation de la transcription , Cellules cultivées , Protéines de liaison à l'ADN/antagonistes et inhibiteurs , Régulation de l'expression des gènes viraux , Humains , Mutagenèse , Protéines des oncogènes viraux/antagonistes et inhibiteurs , Liaison aux protéines , Structure tertiaire des protéines/génétique , Structure tertiaire des protéines/effets des radiations , Délétion de séquence
4.
Community Ment Health J ; 37(4): 347-58, 2001 Aug.
Article de Anglais | MEDLINE | ID: mdl-11482752

RÉSUMÉ

Stealing behaviors are common among youth and adolescents and often begin in early ages due to a variety of developmental, behavioral, and social factors. This study explores the prevalence of stealing behaviors in a South Texas juvenile detention facility. Researchers discovered stealing was the most frequently reported offense followed by the lack of supervision. Youth arrested for stealing were also more likely to be arrested prior to their twelfth birthday, have subsequent charges that may include assault, and have multiple charges. Results with implications for interventions are provided.


Sujet(s)
Délinquance juvénile/statistiques et données numériques , Vol (infraction)/statistiques et données numériques , Adolescent , Répartition par âge , Analyse de variance , Loi du khi-deux , Enfant , Troubles du comportement de l'enfant , Ethnies , Relations familiales , Femelle , Humains , Délinquance juvénile/classification , Délinquance juvénile/prévention et contrôle , Mâle , Texas/épidémiologie , Vol (infraction)/classification , Vol (infraction)/prévention et contrôle , Violence/prévention et contrôle , Violence/statistiques et données numériques
5.
Biochem J ; 357(Pt 3): 617-23, 2001 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-11463333

RÉSUMÉ

The transcription factor nuclear factor kappa B (NF-kappa B) plays a pivotal role in inflammatory processes through induction of adhesion molecules and chemokines. The zinc finger molecule A20 is an important negative regulator of NF-kappa B. The mechanism utilized by A20 is not fully understood, but A20 has been shown to bind to tumour-necrosis-factor-receptor-associated factor (TRAF) molecules, which are necessary for pro-inflammatory cytokine signalling. We report two novel genes, Cezanne (cellular zinc finger anti-NF-kappa B) and TRABID (TRAF-binding domain), with sequence similarity to A20. Co-immunoprecipitation studies indicated that TRAF6 was able to interact with both Cezanne and TRABID. In contrast, reporter gene experiments revealed a specific ability of Cezanne to down-regulate NF-kappa B. It is likely, therefore, that Cezanne participates in the regulation of inflammatory processes.


Sujet(s)
Endopeptidases/isolement et purification , Facteur de transcription NF-kappa B/métabolisme , Protéines/isolement et purification , Séquence d'acides aminés , Animaux , Cellules cultivées , Clonage moléculaire , Cysteine endopeptidases , Protéines de liaison à l'ADN , Endopeptidases/génétique , Endopeptidases/métabolisme , Régulation de l'expression des gènes , Humains , Protéines et peptides de signalisation intracellulaire , Souris , Données de séquences moléculaires , Protéines nucléaires , Protéines/génétique , Protéines/métabolisme , Similitude de séquences d'acides aminés , Fractions subcellulaires , Facteur-6 associé aux récepteurs de TNF , Transcription génétique , Protéine-3 induite par le facteur de nécrose tumorale alpha
6.
Transplantation ; 71(3): 457-60, 2001 Feb 15.
Article de Anglais | MEDLINE | ID: mdl-11233910

RÉSUMÉ

Endothelial damage has been implicated in the pathogenesis of chronic rejection. Conversely, expression of protective genes [including A20, A1, bcl-xl, and hemoxygenase-1 (HO-1)] in the endothelium has been associated with long-term graft survival. Overexpression of protective genes in cultured endothelial cells confers protection from apoptosis and prevents expression of inflammatory molecules through inactivation of NF-kappaB. CD31 (PECAM-1) expressed at endothelial cell junctions is ligated by leukocytes during transendothelial migration. Our laboratory has recently shown that cross-linking CD31 using a monoclonal antibody (LCI-4) triggers signaling events in endothelial cells. In this study, we demonstrate that treatment with LCI-4 protected serum-starved endothelial cells from apoptosis. CD31 cross-linking also led to elevation of A20 and A1 mRNA levels and activation of the transcription factor Sp-1. In summary, signaling through CD31 on endothelial cells leads to protection from apoptosis in association with up-regulation of two protective molecules, A20 and A1.


Sujet(s)
Endothélium vasculaire/cytologie , Antigènes CD31/physiologie , Animaux , Apoptose/effets des médicaments et des substances chimiques , Humains , Antigènes CD31/génétique , Transduction du signal/immunologie , Activation de la transcription
7.
Adolescence ; 34(134): 293-303, 1999.
Article de Anglais | MEDLINE | ID: mdl-10494978

RÉSUMÉ

One hundred sixty-six pregnant or parenting adolescent females completed a survey regarding early sexual experiences (wanted and unwanted), family dysfunction and violence, and health-risky behaviors occurring prior to age 18. Fifty-three percent had at least one unwanted sexual experience. Younger age at first unwanted sexual experience was associated with younger age at first wanted sexual experience. Adolescent females with an unwanted sexual experience, as compared to those without, were more likely to be victims of physical violence, to have run away, to be substance abusers, and to have family members with drug or alcohol problems. Four factors explained 39% of the variance in age at first pregnancy: presence of a family member with a drinking problem, age first got hit with a belt or other object by a family member, age first got drunk, and age at first wanted sexual experience. It was concluded that the prevention of teenage pregnancy entails a multifaceted approach that addresses family life, early sexual experiences, and health-risky behaviors.


Sujet(s)
Violence sexuelle chez l'enfant , Grossesse de l'adolescente , Prise de risque , Comportement sexuel , Adolescent , Consommation d'alcool , Femelle , Humains , Grossesse , Infractions sexuelles , Troubles liés à une substance
8.
J Biomol Struct Dyn ; 15(6): 1181-94, 1998 Jun.
Article de Anglais | MEDLINE | ID: mdl-9669563

RÉSUMÉ

The ability of pyrimidine bases to adopt the syn conformation in DNA has been investigated. The distances between atoms on the sugar and base and the resulting steric energies have been calculated as a function of glycosidic torsion angle for the principal sugar puckers of the deoxyribose of cytosine. The results indicate that pyrimidines can assume both the anti and syn conformations for the 3E, 4E, 1E, 2E, 3E sugar puckers and syn for the 2E sugar pucker. For these sugar puckers the difference between the minimum energies of the anti and syn conformations is in the range of 0.1-2.0 kcal/mole, with the minimum syn energy being lower in the case of the 4E, 1E and 2E sugar puckers. It is particularly significant that cytosine can assume the syn conformation for the 3E sugar pucker commonly observed for the syn nucleotides in Z-DNA with both alternating pyrimidine/purine (APP) and non-APP sequences. The results of this investigation confirm that steric interactions resulting from putting a pyrimidine nucleotide in the syn conformation are not a major factor in the preference for APP base sequences in Z-DNA.


Sujet(s)
ADN/composition chimique , Désoses , Conformation d'acide nucléique , Pyrimidines
9.
Am J Health Promot ; 12(4): 246-53, 1998.
Article de Anglais | MEDLINE | ID: mdl-10178617

RÉSUMÉ

PURPOSE: This study compares the efficacy of a self-help intervention tailored to the individual's stage of motivational readiness for exercise adoption with a standard self-help exercise promotion intervention. DESIGN: Interventions were delivered at baseline and 1 month; assessments were collected at baseline and 3 months. SETTING: Eleven worksites participating in the Working Healthy Research Trial. SUBJECTS: Participants (n = 1559) were a subsample of employees at participating worksites, individually randomized to one of two treatment conditions. INTERVENTION: Printed self-help exercise promotion materials either (1) matched to the individual's stage of motivational readiness for exercise adoption (motivationally tailored), or (2) standard materials (standard). MEASURES: Measures of stage of motivational readiness for exercise and items from the 7-Day Physical Activity Recall. RESULTS: Among intervention completers (n = 903), chi-square analyses showed that, compared to the standard intervention, those receiving the motivationally tailored intervention were significantly more likely to show increases (37% vs. 27%) and less likely to show either no change (52% vs. 58%) or regression (11% vs. 15%) in stage of motivational readiness. Multivariate analyses of variance showed that changes in stage of motivational readiness were significantly associated with changes in self-reported time spent in exercise. CONCLUSIONS: This is the first prospective, randomized, controlled trial demonstrating the efficacy of a brief motivationally tailored intervention compared to a standard self-help intervention for exercise adoption. These findings appear to support treatment approaches that tailor interventions to the individual's stage of motivational readiness for exercise adoption.


Sujet(s)
Exercice physique/psychologie , Promotion de la santé/méthodes , Motivation , Santé au travail , Adulte , Analyse de variance , Femelle , Humains , Mâle , Analyse de régression , Rhode Island
10.
Behav Sci Law ; 15(4): 469-82, 1997.
Article de Anglais | MEDLINE | ID: mdl-9433749

RÉSUMÉ

Provision of mental health services to correctional populations places considerable demands on clinical staff to provide efficient and effective means to screen patients for severe mental disorders and other emergent conditions that necessitate immediate interventions. Among the highly problematic behaviors found in correctional settings are forms of acting out (e.g., suicide and aggression towards others) and response style (e.g., motivations to malinger). The current study examined the usefulness of the Personality Assessment Inventory (PAI) in assessing problematic behaviors in a corrections-based psychiatric hospital. As evidence of criterion related validity, selected PAI scales were compared to (a) evidence of malingering on the Structured Interview of Reported Symptoms (SIRS), (b) suicidal threats and gestures, and (c) ratings of aggression on the Overt Aggression Scale (OAS). In general, results supported the use of the PAI for the assessment of these problematic behaviors.


Sujet(s)
Psychiatrie légale/méthodes , Inventaire de personnalité/normes , Prisonniers/psychologie , Psychométrie/normes , Adulte , Agressivité/classification , Analyse de variance , Loi du khi-deux , Études transversales , Humains , Mâle , Simulation/diagnostic , Projets pilotes , Reproductibilité des résultats , Études rétrospectives , Appréciation des risques , Suicide/psychologie , Violence
11.
Addict Behav ; 20(1): 87-92, 1995.
Article de Anglais | MEDLINE | ID: mdl-7785485

RÉSUMÉ

We examined the effects of physical exercise on smoking relapse. Twenty previously sedentary female smokers were randomly assigned to smoking cessation plus exercise or smoking cessation with frequency contact control. The smoking cessation program included 12 professionally led sessions over 12 weeks. Exercise treatment included three supervised exercise sessions per week for 15 weeks. Contact control included three women's health/wellness lectures per week for 15 weeks. Smoking abstinence was validated by carbon monoxide and saliva cotinine. Mean exercise attendance for exercise subjects was 88% with an increase in estimated VO2 of 25%. The percentage of subjects who quit for 24 hours was 80% for the exercise and 90% for the contact group. One subject in the contact group remained abstinent at the end of the 12-week treatment and at 1-, 3-, and 12-month follow-ups, whereas three subjects in the exercise group were abstinent at these time points. These results suggest that exercise training improves short-term quit rates and may prove a useful strategy for long-term maintenance of smoking cessation.


Sujet(s)
Exercice physique/psychologie , Identité de genre , Arrêter de fumer/psychologie , Adulte , Poids , Association thérapeutique , Femelle , Études de suivi , Humains , Adulte d'âge moyen , Aptitude physique/psychologie , Résultat thérapeutique
12.
Am J Health Promot ; 9(1): 49-55, 1994.
Article de Anglais | MEDLINE | ID: mdl-10147495

RÉSUMÉ

PURPOSE: This study examines the utility of three theoretical models--the stages of change model, self-efficacy theory, and the decisional balance model--in understanding exercise behavior among employed women. DESIGN: Data for this cross-sectional study were collected as part of a routine follow-up of a worksite-based smoking and health risk appraisal study. SETTING: The study was conducted in three Rhode Island worksites, including one manufacturing company, one medical center, and one retail outlet. SUBJECTS: Of a sample of 431 women who completed exercise questionnaires, 293 reported participation in a physical activity over the previous week. The average age of the sample was 41.1 years, and mean years of education was 12.8. MEASURES: Previously validated measures to determine stage of exercise behavior, exercise self-efficacy, exercise decisional balance, and physical activity participation were administered. Additional demographic information was also obtained. RESULTS: Frequency counts revealed that 39% of the population was sedentary, 34% were participating in irregular activity, and 27% were active. MANOVAs followed by one way ANOVAs revealed that women in Precontemplation scored the lowest and those in Maintenance scored the highest on the self-efficacy, pro, and decisional-balance indices, with the trend reversed on the con scale. A chi-square test revealed that women with one or more young children in the home were more likely to be in a lower stage of exercise adoption. CONCLUSIONS: Most of the women in this cross-sectional study did not engage in regular activity. Presence of young children in the home was significantly related to decreased activity.(ABSTRACT TRUNCATED AT 250 WORDS)


Sujet(s)
Exercice physique , Femmes qui travaillent , Démographie , Femelle , Humains , Modèles théoriques , Concept du soi , Enquêtes et questionnaires
13.
Tex Med ; 90(6): 56-62, 1994 Jun.
Article de Anglais | MEDLINE | ID: mdl-7521068

RÉSUMÉ

A comprehensive system for the delivery of care to children with special healthcare needs and to their families has been developed by the department of pediatrics of The University of Texas Health Science Center at San Antonio. A description of the structure and operations of this system is presented and offered as a model for the state of Texas.


Sujet(s)
Protection de l'enfance , Incapacités de développement , Adolescent , Enfant , Enfant d'âge préscolaire , Prestations des soins de santé/économie , Prestations des soins de santé/organisation et administration , Prestations des soins de santé/normes , Femelle , Éducation pour la santé , Personnel de santé/enseignement et éducation , Accessibilité des services de santé , Besoins et demandes de services de santé , Humains , Nourrisson , Nouveau-né , Mâle , Orientation vers un spécialiste , Texas , États-Unis
14.
Plant Mol Biol ; 24(6): 853-62, 1994 Mar.
Article de Anglais | MEDLINE | ID: mdl-8204823

RÉSUMÉ

Legumes, and a very few non-legume plant species, are known to possess functioning haemoglobin genes. We describe here the characterization of a haemoglobin cDNA isolated from barley. The deduced amino acid sequence shows 71% amino acid identity with a non-legume haemoglobin gene, a further 16% of the residues being conservative replacements. The barley cDNA also hybridizes to genomic sequences in rye, maize and wheat. The demonstration of a gene from a monocotyledon with close sequence homology to the known non-legume plant haemoglobins fills a major gap in the known distribution of haemoglobin genes in the plant kingdom. The expression of the gene is induced in isolated barley aleurone layers exposed to anaerobic conditions, and the roots of flooding-stressed barley plants. The expression of the RNA under anoxic conditions is similar to that of a known anaerobic response gene, alcohol dehydrogenase. Our results suggest that the increased expression of haemoglobin RNA is an integral part of the normal anaerobic response in barley. The findings are discussed in the light of current theories of haemoglobin function and evolution.


Sujet(s)
Grains comestibles/génétique , Gènes de plante , Hémoprotéines/génétique , Protéines végétales/génétique , Alcohol dehydrogenase/génétique , Séquence d'acides aminés , Anaérobiose/génétique , Séquence nucléotidique , Clonage moléculaire , Régulation de l'expression des gènes/physiologie , Hordeum/génétique , L-Lactate dehydrogenase/génétique , Données de séquences moléculaires , Graines/génétique , Zea mays/génétique
18.
J Biomol Struct Dyn ; 10(3): 533-50, 1992 Dec.
Article de Anglais | MEDLINE | ID: mdl-1492923

RÉSUMÉ

An alternate model for surface noncovalent and surface covalent binding of aflatoxin B1 to N(7) of guanine in DNA is proposed. This model considers the out-of-plane motions of C(8) of aflatoxin B1 in those interactions. The covalent intercalated fit of aflatoxin B1 into DNA arises from steric adjustments made by DNA at the covalent intercalation site as well as local strain in the bond angles about N(7) of guanine and C(8) of aflatoxin B1. The bond angle about N(7) deviates modestly from the sp2 value toward the sp3 value. This study suggests that the surface covalent aflatoxin B1-DNA complex serves only a minor role in aflatoxin's precarcinogenic interaction with DNA and is a likely correctable error.


Sujet(s)
Aflatoxine B1/composition chimique , Adduits à l'ADN , ADN/composition chimique , Guanine/composition chimique , Séquence nucléotidique , Sites de fixation , Conformation moléculaire , Diffraction des rayons X
19.
Opt Lett ; 17(11): 807-9, 1992 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-19794638

RÉSUMÉ

Wavelength tuning and broad-bandwidth operation of a passively mode-locked Nd:fiber laser is demonstrated at 1060 microm. The oscillator pulses are used to seed a bulk regenerative Nd:glass amplifier, and 300-fs transformlimited pulses with an energy of 10 microJ are obtained after 31 round trips at a repetition rate of 500 Hz.

20.
J Mol Endocrinol ; 7(2): 145-54, 1991 Oct.
Article de Anglais | MEDLINE | ID: mdl-1930626

RÉSUMÉ

Insulin-like growth factor-II (IGF-II) is a polypeptide mitogen which is believed to play an important role in fetal development. The human and rat IGF-II genes are complex transcription units, which contain multiple promoters and polyadenylation sites and which exhibit alternate splicing of their primary transcripts. In order to study IGF-II gene expression during chick embryonic development, we screened a 10-day chick embryo cDNA library with a human IGF-II cDNA probe. We isolated a clone, designated cigf, that was comprised, in part, of sequences homologous to the second coding exon of the human, mouse and rat IGF-II genes. Comparison of the nucleotide sequence of cigf with that of the corresponding genomic clone indicated that cigf was derived from a spliced antisense transcript of the chicken IGF-II gene, which overlapped the second coding exon. Northern blotting experiments with single-stranded RNA probes synthesized using cigf DNA as a template showed that stage 22 and stage 36 chick embryos contained sense strand IGF-II transcripts of 1.4, 2.2, 4.7 and 7.0 kb and antisense strand transcripts of 0.7, 1.3, 1.8, 2.5, 4.9, 6.0 and 8.0 kb. The pattern of sense strand IGF-II transcripts was similar to that previously found in rat fetal tissues. Whilst there are precedents for the transcription of both strands of a single gene, this is the first evidence for antisense transcription of an IGF gene. The functions of the antisense transcripts remain to be determined. These findings demonstrate a further level of complexity in the IGF-II transcription unit and indicate that studies of IGF-II transcript distribution performed with double-stranded probes should be interpreted with caution. They also suggest explanations for the recent finding that IGF-II peptides are present at much lower levels in embryos than expected from the high levels of IGF-II transcripts present.


Sujet(s)
ADN/génétique , Facteur de croissance IGF-II/génétique , ARN antisens/génétique , Transcription génétique , Animaux , Séquence nucléotidique , Technique de Northern , Technique de Southern , Embryon de poulet , ADN/analyse , Exons/génétique , Humains , Facteur de croissance IGF-II/métabolisme , Données de séquences moléculaires , Hybridation d'acides nucléiques , Rats
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