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1.
Inj Prev ; 21(1): 35-41, 2015 Feb.
Article de Anglais | MEDLINE | ID: mdl-25024394

RÉSUMÉ

OBJECTIVES: Although there is a large and growing body of evidence concerning the impact of contracting economies on suicide mortality risk, far less is known about the role alcohol consumption plays in the complex relationship between economic conditions and suicide. The aims were to compare the postmortem alcohol intoxication rates among male and female suicide decedents before (2005-2007), during (2008-2009) and after (2010-2011) the economic contraction in the USA. METHODS: Data from the restricted National Violent Death Reporting System (2005-2011) for male and female suicide decedents aged 20 years and older were analysed by Poisson regression analysis to test whether there was significant change in the fractions of suicide decedents who were acutely intoxicated at the time of death (defined as blood alcohol content ≥0.08 g/dL) prior, during and after the downturn. RESULTS: The fraction of all suicide decedents with alcohol intoxication increased by 7% after the onset of the recession from 22.2% in 2005-2007 to 23.9% in 2008-2011. Compared with the years prior to the recession, male suicide decedents showed a 1.09-fold increased risk of alcohol intoxication within the first 2 years of the recession. Surprisingly, there was evidence of a lag effect among female suicide decedents, who had a 1.14-fold (95% CI 1.02 to 1.27) increased risk of intoxication in 2010-2011 compared with 2005-2007. CONCLUSIONS: These findings suggest that acute alcohol intoxication in suicide interacts with economic conditions, becoming more prevalent during contractions.


Sujet(s)
Intoxication alcoolique/mortalité , Revenu , Pauvreté , Suicide/statistiques et données numériques , Répartition par âge , Intoxication alcoolique/sang , Intoxication alcoolique/psychologie , Autopsie , Analyse chimique du sang , Femelle , Humains , Mâle , Surveillance de la population , Valeur prédictive des tests , Prévalence , Facteurs de risque , Répartition par sexe , Facteurs socioéconomiques , Suicide/psychologie , États-Unis/épidémiologie
2.
Nat Commun ; 5: 4235, 2014 Jun 23.
Article de Anglais | MEDLINE | ID: mdl-24953740

RÉSUMÉ

Molecules can efficiently and selectively convert light energy into other degrees of freedom. Disentangling the underlying ultrafast motion of electrons and nuclei of the photoexcited molecule presents a challenge to current spectroscopic approaches. Here we explore the photoexcited dynamics of molecules by an interaction with an ultrafast X-ray pulse creating a highly localized core hole that decays via Auger emission. We discover that the Auger spectrum as a function of photoexcitation--X-ray-probe delay contains valuable information about the nuclear and electronic degrees of freedom from an element-specific point of view. For the nucleobase thymine, the oxygen Auger spectrum shifts towards high kinetic energies, resulting from a particular C-O bond stretch in the ππ* photoexcited state. A subsequent shift of the Auger spectrum towards lower kinetic energies displays the electronic relaxation of the initial photoexcited state within 200 fs. Ab-initio simulations reinforce our interpretation and indicate an electronic decay to the nπ* state.

3.
Nat Commun ; 5: 4281, 2014 Jun 27.
Article de Anglais | MEDLINE | ID: mdl-24969734

RÉSUMÉ

Understanding molecular femtosecond dynamics under intense X-ray exposure is critical to progress in biomolecular imaging and matter under extreme conditions. Imaging viruses and proteins at an atomic spatial scale and on the time scale of atomic motion requires rigorous, quantitative understanding of dynamical effects of intense X-ray exposure. Here we present an experimental and theoretical study of C60 molecules interacting with intense X-ray pulses from a free-electron laser, revealing the influence of processes not previously reported. Our work illustrates the successful use of classical mechanics to describe all moving particles in C60, an approach that scales well to larger systems, for example, biomolecules. Comparisons of the model with experimental data on C60 ion fragmentation show excellent agreement under a variety of laser conditions. The results indicate that this modelling is applicable for X-ray interactions with any extended system, even at higher X-ray dose rates expected with future light sources.


Sujet(s)
Fullerènes , Simulation de dynamique moléculaire , Rayons X , Explosions , Lasers
4.
J Chem Phys ; 139(16): 164318, 2013 Oct 28.
Article de Anglais | MEDLINE | ID: mdl-24182040

RÉSUMÉ

High resolution electron kinetic energy spectra of iron pentacarbonyl (Fe(CO)5) are studied in the photon energy range of 40-90 eV. The relative yield of photolines associated with the Fe 3d level shows a Fano line shape at photon energies of 61 eV. The increase in signal from the 3d level is indicative of resonant photoemission involving 3p-3d transitions at the M edge of iron. The signature of this resonance is also present in photolines typically attributed to be mostly CO in character. We use the modulation depth of the Fano resonances to reinterpret the photoelectron lines in the literature.

5.
Ann Rheum Dis ; 72(1): 37-42, 2013 Jan.
Article de Anglais | MEDLINE | ID: mdl-22523429

RÉSUMÉ

OBJECTIVE: In North America, tuberculosis and nontuberculous mycobacterial (NTM) disease rates associated with antitumour necrosis factor α (anti-TNFα) therapy are unknown. METHODS: At Kaiser Permanente Northern California, the authors searched automated pharmacy records to identify inflammatory disease patients who received anti-TNF therapy during 2000-2008 and used validated electronic search algorithms to identify NTM and tuberculosis cases occurring during anti-TNF drug exposure. RESULTS: Of 8418 anti-TNF users identified, 60% had rheumatoid arthritis (RA). Among anti-TNF users, 18 developed NTM and 16 tuberculosis after drug start. Anti-TNF associated rates of NTM and tuberculosis were 74 (95% CI: 37 to 111) and 49 (95% CI: 18 to 79) per 100 000 person-years, respectively. Rates (per 100, 000 person-years) for NTM and tuberculosis respectively for etanercept were 35 (95% CI: 1 to 69) and 17 (95% CI: 0 to 41); infliximab, 116 (95% CI: 30 to 203) and 83 (95% CI: 10 to 156); and adalimumab, 122 (95% CI: 3 to 241) and 91 (95% CI: 19 to 267). Background rates for NTM and tuberculosis in unexposed RA-patients were 19.2 (14.2 to 25.0) and 8.7 (5.3 to 13.2), and in the general population were 4.1 (95% CI 3.9 to 4.4) and 2.8 (95% CI 2.6 to 3.0) per 100, 000 person-years. Among anti-TNF users, compared with uninfected individuals, NTM case-patients were older (median age 68 vs 50 years, p<0.01) and more likely to have RA (100% vs 60%, p<0.01); whereas, tuberculosis case-patients were more likely to have diabetes (37% vs 16%, p=0.02) or chronic renal disease (25% vs 6%, p=0.02). CONCLUSIONS: Among anti-TNF users in USA, mycobacterial disease rates are elevated, and NTM is associated with RA.


Sujet(s)
Polyarthrite rhumatoïde/traitement médicamenteux , Immunosuppresseurs/effets indésirables , Infections à Mycobacterium/induit chimiquement , Infections à Mycobacterium/épidémiologie , Facteur de nécrose tumorale alpha/antagonistes et inhibiteurs , Adalimumab , Animaux , Anticorps monoclonaux/effets indésirables , Anticorps monoclonaux humanisés/effets indésirables , Études de cohortes , Étanercept , Femelle , Humains , Immunoglobuline G/effets indésirables , Incidence , Infliximab , Mâle , Adulte d'âge moyen , Récepteurs aux facteurs de nécrose tumorale , États-Unis/épidémiologie
6.
Phys Rev Lett ; 104(25): 253002, 2010 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-20867372

RÉSUMÉ

Sequential multiple photoionization of the prototypical molecule N2 is studied with femtosecond time resolution using the Linac Coherent Light Source (LCLS). A detailed picture of intense x-ray induced ionization and dissociation dynamics is revealed, including a molecular mechanism of frustrated absorption that suppresses the formation of high charge states at short pulse durations. The inverse scaling of the average target charge state with x-ray peak brightness has possible implications for single-pulse imaging applications.

7.
Phys Rev Lett ; 105(8): 083004, 2010 Aug 20.
Article de Anglais | MEDLINE | ID: mdl-20868096

RÉSUMÉ

The Linac Coherent Light Source free electron laser is a source of high brightness x rays, 2×10(11) photons in a ∼5 fs pulse, that can be focused to produce double core vacancies through rapid sequential ionization. This enables double core vacancy Auger electron spectroscopy, an entirely new way to study femtosecond chemical dynamics with Auger electrons that probe the local valence structure of molecules near a specific atomic core. Using 1.1 keV photons for sequential x-ray ionization of impulsively aligned molecular nitrogen, we observed a rich single-site double core vacancy Auger electron spectrum near 413 eV, in good agreement with ab initio calculations, and we measured the corresponding Auger electron angle dependence in the molecular frame.


Sujet(s)
Électrons , Phénomènes physiques , Lumière , Azote/composition chimique , Théorie quantique , Analyse spectrale , Facteurs temps
8.
Opt Express ; 18(17): 17620-30, 2010 Aug 16.
Article de Anglais | MEDLINE | ID: mdl-20721148

RÉSUMÉ

The first time-resolved x-ray/optical pump-probe experiments at the SLAC Linac Coherent Light Source (LCLS) used a combination of feedback methods and post-analysis binning techniques to synchronize an ultrafast optical laser to the linac-based x-ray laser. Transient molecular nitrogen alignment revival features were resolved in time-dependent x-ray-induced fragmentation spectra. These alignment features were used to find the temporal overlap of the pump and probe pulses. The strong-field dissociation of x-ray generated quasi-bound molecular dications was used to establish the residual timing jitter. This analysis shows that the relative arrival time of the Ti:Sapphire laser and the x-ray pulses had a distribution with a standard deviation of approximately 120 fs. The largest contribution to the jitter noise spectrum was the locking of the laser oscillator to the reference RF of the accelerator, which suggests that simple technical improvements could reduce the jitter to better than 50 fs.


Sujet(s)
Électrons , Lasers , Synchrotrons , Conception d'appareillage , Fibres optiques , Facteurs temps , Rayons X
9.
Opt Lett ; 35(12): 2028-30, 2010 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-20548375

RÉSUMÉ

We create a transient Bragg grating in a high-harmonic generation medium using two counterpropagating pulses. The Bragg grating disperses the harmonics in angle and can diffract a large bandwidth with temporal resolution limited only by the source size.

10.
Inj Prev ; 15(5): 322-7, 2009 Oct.
Article de Anglais | MEDLINE | ID: mdl-19805601

RÉSUMÉ

OBJECTIVE: To examine the risk factors and precipitating circumstances associated with firearm suicide. METHODS: Data from the restricted National Violent Death Reporting System (2003-6) for 25 491 male and female suicide decedents aged 18 and older were analysed by multiple logistic regression to estimate the relative odds of firearm use with 95% CIs. RESULTS: Firearms were often used in male (58.1%) and female (31.2%) suicides. Among male decedents, older age, veteran status, residing in areas with higher rates of firearm availability, raised blood alcohol concentration, acute crisis and relationship problems were all associated with firearm use. Conversely, men with a diagnosis of a mental health problem, a history of suicide attempts or alcohol problems had lower odds of firearm use. Among female decedents, factors with a significant effect on firearm use included: being older, married, white and a veteran; residing in areas with higher rates of firearm availability; having an acute crisis; having experienced the death of a relative or friend; being depressed; and having relationship problems. Of note, women who had a treated DSM-IV-diagnosed problem, previous suicide attempts and physical health problems were less likely to use firearms. CONCLUSIONS: These findings challenge the conventional view that those who are severely depressed and suicidal are prone to highly lethal methods, such as firearms. Rather, firearms users may be reacting to acute situations.


Sujet(s)
Armes à feu/statistiques et données numériques , Suicide/statistiques et données numériques , Plaies par arme à feu/mortalité , Adolescent , Adulte , Facteurs âges , Sujet âgé , Consommation d'alcool/épidémiologie , Consommation d'alcool/psychologie , Diagnostic and stastistical manual of mental disorders (USA) , Méthodes épidémiologiques , Éthanol/sang , Femelle , Humains , Mâle , Troubles mentaux/épidémiologie , Troubles mentaux/psychologie , Adulte d'âge moyen , Facteurs sexuels , Suicide/psychologie , Tentative de suicide/psychologie , Tentative de suicide/statistiques et données numériques , États-Unis/épidémiologie , Plaies par arme à feu/psychologie , Jeune adulte
11.
Opt Express ; 17(17): 15134-44, 2009 Aug 17.
Article de Anglais | MEDLINE | ID: mdl-19687991

RÉSUMÉ

We present a method that allows for a convenient switching between high harmonic generation (HHG) and accurate calibration of the vacuum ultraviolet (VUV) spectrometer used to analyze the harmonic spectrum. The accurate calibration of HHG spectra is becoming increasingly important for the determination of electronic structures. The wavelength of the laser harmonics themselves depend on the details of the harmonic geometry and phase matching, making them unsuitable for calibration purposes. In our calibration mode, the target resides directly at the focus of the laser, thereby enhancing plasma emission and suppressing harmonic generation. In HHG mode, the source medium resides in front or after the focus, showing enhanced HHG and no plasma emission lines. We analyze the plasma emission and use it for a direct calibration of our HHG spectra.


Sujet(s)
Lasers , Spectrophotométrie UV/méthodes , Calibrage , Simulation numérique , Électronique , Conception d'appareillage , Lumière , Optique et photonique , Théorie quantique , Diffusion de rayonnements
12.
Science ; 315(5812): 633-6, 2007 Feb 02.
Article de Anglais | MEDLINE | ID: mdl-17272718

RÉSUMÉ

Intense femtosecond laser excitation can produce transient states of matter that would otherwise be inaccessible to laboratory investigation. At high excitation densities, the interatomic forces that bind solids and determine many of their properties can be substantially altered. Here, we present the detailed mapping of the carrier density-dependent interatomic potential of bismuth approaching a solid-solid phase transition. Our experiments combine stroboscopic techniques that use a high-brightness linear electron accelerator-based x-ray source with pulse-by-pulse timing reconstruction for femtosecond resolution, allowing quantitative characterization of the interatomic potential energy surface of the highly excited solid.

15.
Am J Prev Med ; 21(4): 306-12, 2001 Nov.
Article de Anglais | MEDLINE | ID: mdl-11701302

RÉSUMÉ

INTRODUCTION: According to the Centers for Disease Control and Prevention and the World Health Organization, increasing physical activity may help prolong health and preserve the quality of life in late adulthood. Physical activity has taken center stage as the behavior most likely to alter health. However, there is little recent population-wide information about the demographic and psychosocial correlates of physical activity in the elderly population. The purpose of the study was to identify the factors associated with older adults' frequency of physical activity. The study may have implications for preventive interventions. METHODS: Data for 12,611 community-dwelling people aged > or = 65 from the 1996-1997 Canadian National Population Health Survey were examined. Predictors of frequent versus infrequent self-reported physical activity lasting > 15 minutes were examined using logistic regression analyses. The predictor variables included geographic location, psychological distress (Generalized Distress Scale), demographic factors (age, gender, educational level, and marital status), perceived social support, chronic medical conditions, physical limitations due to injury, functional limitations, smoking behavior, and body mass index (BMI). RESULTS: Gender (male); younger age; higher levels of education; being unmarried; absence of chronic conditions, injuries, and functional limitations; lower BMI; social support (females); nonsmoking; region; and lower levels of psychological distress were associated with frequent physical activity in late life. Older adults in western Canadian provinces were more active than those in eastern provinces. CONCLUSIONS: The results will be useful for the design of interventions aimed at improving older adults' health behavior and other health and functional outcomes, especially for subgroups in particular need. Recommendations for further longitudinal research are presented.


Sujet(s)
Gériatrie , Activités de loisirs , Surveillance de la population , Sujet âgé , Canada , Niveau d'instruction , Exercice physique , Femelle , Enquêtes de santé , Humains , Modèles logistiques , Mâle , Situation de famille , Soutien social
16.
Am J Epidemiol ; 154(2): 180-7, 2001 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-11447053

RÉSUMÉ

The objective of this study was to develop and validate algorithms to detect pregnancies from the time of first clinical recognition by using Kaiser Permanente automated databases from Portland, Oregon. In 1993--1994, the authors evaluated these databases retrospectively to identify markers indicative of initial clinical detection of pregnancy and pregnancy outcomes. Pregnancy markers were found for 99% of the women for whom pregnancy outcomes were included in the automated databases, and pregnancy outcomes were identified for 77% of the women for whom there were pregnancy markers. The earliest marker most predictive of a pregnancy outcome was a positive human chorionic gonadotropin test; least predictive was an obstetric outpatient visit. Medical record review indicated that in a sample of women with pregnancy markers in the database, an estimated 6% of pregnancy outcomes (primarily early fetal deaths and elective terminations) were lost. Pregnancies were first captured in automated databases 6--8 weeks after the last menstrual period, and a combination of a positive human chorionic gonadotropin test and an outpatient obstetric visit was the most sensitive and specific early marker of pregnancy. When combined with automated pharmacy records, these databases may be valuable tools for evaluating prescription drug effects on all major outcomes of clinically recognized pregnancies.


Sujet(s)
Interruption légale de grossesse/statistiques et données numériques , Algorithmes , Soins ambulatoires/statistiques et données numériques , Marqueurs biologiques/sang , Marqueurs biologiques/urine , Gonadotrophine chorionique/sang , Gonadotrophine chorionique/urine , Bases de données factuelles , Tests de grossesse/méthodes , Tests de grossesse/normes , Prise en charge prénatale/statistiques et données numériques , Orientation vers un spécialiste/statistiques et données numériques , Échographie prénatale/statistiques et données numériques , Adolescent , Adulte , Ordonnances médicamenteuses/statistiques et données numériques , Femelle , Health Maintenance Organizations (USA) , Humains , Orégon/épidémiologie , Grossesse , Issue de la grossesse/épidémiologie , Premier trimestre de grossesse , Études rétrospectives , Sensibilité et spécificité , Facteurs temps
17.
Proc Natl Acad Sci U S A ; 98(16): 9231-6, 2001 Jul 31.
Article de Anglais | MEDLINE | ID: mdl-11470892

RÉSUMÉ

Comparison of crystallized MHC class II*peptide complexes has revealed that, in addition to pocket interactions involving the peptide side chains, peptide binding to MHC class II molecules is characterized by a series of hydrogen bonds between genetically conserved amino acid residues in the class II molecule and the main chain of the peptide. Many class II*peptide structures have two sets of symmetrical hydrogen bonds at the opposite ends of the class II antigen-binding groove (beta-His-81, beta-Asn-82 vs. alpha-His-68, alpha-Asn-69). In this study, we alter these peripheral hydrogen bonds and measure the apparent contribution of each to the kinetic stability of peptide* II complexes. Single conservative amino substitutions were made in the I-A(d) protein to eliminate participation as a hydrogen bonding residue, and the kinetic stability of a diverse set of peptides bound to the substituted I-A(d) proteins was measured. Although each hydrogen bond does contribute to peptide binding, our results point to the striking conclusion that those hydrogen bonds localized to the amino terminus of the peptide contribute profoundly and disproportionately to the stability of peptide interactions with I-A(d). We suggest that the peripheral hydrogen bonds at the amino terminus of the bound peptide that are conserved in all class II*peptide crystal structures solved thus far form a cooperative network that critically regulates peptide dissociation from the class II molecule.


Sujet(s)
Antigènes d'histocompatibilité de classe II/composition chimique , Peptides/composition chimique , Séquence d'acides aminés , Animaux , Sites de fixation , Lignée cellulaire , Souris , Données de séquences moléculaires
19.
Adm Policy Ment Health ; 28(6): 427-41, 2001 Jul.
Article de Anglais | MEDLINE | ID: mdl-11804010

RÉSUMÉ

Psychiatric advance directives (PADs) are legal documents that permit competent adults to make choices in the present about their future psychiatric treatment if they lose their decision-making capacity. PADs may provide for the appointment of surrogate decision-makers. The present project was undertaken to obtain opinions from the consumer (the patient), provider, and informal caregiver/surrogate about the Oregon PAD. Results of this pilot study show that the majority of no-PAD group consumers reported that they did not get enough help with PAD preparation. The PAD group consumers reported feeling empowered by PAD preparation, but at the follow-up interview, they were less enthusiastic and more critical of PAD policy that was relevant to implementation. Many providers also were concerned about successful PAD implementation. PAD legislation alone does not translate into adequate policy.


Sujet(s)
Directives anticipées/législation et jurisprudence , Attitude envers la santé , Services de santé mentale/législation et jurisprudence , Adulte , Attitude du personnel soignant , Aidants/psychologie , Comportement du consommateur , Prise de décision , Femelle , Personnel de santé/psychologie , Politique de santé/législation et jurisprudence , Humains , Mâle , Orégon , Projets pilotes
20.
Health Serv Res ; 35(4): 813-23, 2000 Oct.
Article de Anglais | MEDLINE | ID: mdl-11055450

RÉSUMÉ

OBJECTIVE: To determine if the incidence of psychiatric emergencies involving drugs or alcohol supports the argument that mentally ill persons contribute to elevated mortality during the days following disbursement of private earnings and public income transfers. STUDY DESIGN: Interrupted time-series using Box-Jenkins methods. DATA COLLECTION/EXTRACTION METHODS: Daily counts of adults admitted to psychiatric emergency services in San Francisco after using drugs or alcohol were derived from medical records for the period January 1 through June 30, 1997. PRINCIPAL FINDINGS: Psychiatric emergencies among males who had used drugs or alcohol were elevated in the early days of the month. Such emergencies among females were not similarly elevated. Emergencies among females who had not used drugs or alcohol were elevated in the early days of the month. CONCLUSION: Elevated mortality in the first week of the month may be attributable, in part, to the "check effect" or use of drugs and alcohol by mentally ill males in the days after they receive income. The contribution of women is more complex and may be induced by drug or alcohol abuse among persons in their social networks. The check effect suggests that persons with a history of substance abuse and mental illness should be offered the opportunity to have their income managed by someone who can monitor and influence how the money is being spent. The fact that drug- or alcohol-related admissions among males exhibit temporal patterns suggests that the provision of preventive as well as treatment services may be strategically scheduled.


Sujet(s)
Alcoolisme/épidémiologie , Services des urgences psychiatriques/statistiques et données numériques , Revenu , Troubles liés à une substance/épidémiologie , Adulte , Alcoolisme/économie , Alcoolisme/mortalité , Diagnostic mixte (psychiatrie) , Femelle , Besoins et demandes de services de santé/économie , Besoins et demandes de services de santé/statistiques et données numériques , Recherche sur les services de santé , Humains , Mâle , Troubles mentaux , Adulte d'âge moyen , Admission du patient/économie , Admission du patient/statistiques et données numériques , Facteurs de risque , San Francisco/épidémiologie , Troubles liés à une substance/économie , Troubles liés à une substance/mortalité
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