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1.
Chemistry ; 30(13): e202303243, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38116883

RESUMEN

In the continuation of previous studies on carbon-rich meso-tetraarylporphyrins featuring 2,7-fluorene units at their periphery, the effect of changing the peripheral dendritic arms for linear arms on their oxygen-photosensitizing ability, their fluorescence and their two-photon absorption (2PA) properties is now analyzed. Thus, starburst porphyrins possessing up to twenty conjugated fluorenyl units were isolated and studied. More precisely, a series of five new free-base porphyrins featuring fully conjugated arms incorporating an increasing number of fluorenyl groups connected via 1,2-alkenyl spacers were synthesized, along with their Zn(II) complexes. Upon excitation in the arm-centred π-π* absorption band, an efficient energy transfer takes place from the peripheral fluorenyl units to the central porphyrin core, leading to intense red-light emission and oxygen photosensitization by the latter. More interestingly, while the linear optical properties of these porphyrins were only slightly improved compared to those of their dendrimer analogues for photodynamic therapy (PDT) or fluorescence imaging, their 2PA cross-sections were much more significantly boosted, evidencing the key role played by different structures on nonlinear optical properties. Finally, by comparison with other porphyrin-based two-photon photosensitizers reported in the literature, we show that these new "semi-disconnected" starburst systems exhibit a remarkable trade-off between intrinsic 2PA, fluorescence and oxygen photosensitization.

2.
Lifetime Data Anal ; 29(2): 441-482, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35799026

RESUMEN

Simple logistic regression can be adapted to deal with right-censoring by inverse probability of censoring weighting (IPCW). We here compare two such IPCW approaches, one based on weighting the outcome, the other based on weighting the estimating equations. We study the large sample properties of the two approaches and show that which of the two weighting methods is the most efficient depends on the censoring distribution. We show by theoretical computations that the methods can be surprisingly different in realistic settings. We further show how to use the two weighting approaches for logistic regression to estimate causal treatment effects, for both observational studies and randomized clinical trials (RCT). Several estimators for observational studies are compared and we present an application to registry data. We also revisit interesting robustness properties of logistic regression in the context of RCTs, with a particular focus on the IPCW weighting. We find that these robustness properties still hold when the censoring weights are correctly specified, but not necessarily otherwise.


Asunto(s)
Modelos Estadísticos , Humanos , Modelos Logísticos , Probabilidad , Causalidad , Simulación por Computador
3.
Chemistry ; 28(23): e202200025, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35199892

RESUMEN

1,1,4,4-Tetracyanobutadienes (TCBDs) bearing a large diversity of fluorophores were prepared following a multi-step synthesis. In a crucial last step, all compounds were obtained from the corresponding ynamides, which were particularly suitable for the formation of the TCBDs in the presence of tetracyanoethylene via a [2+2] cycloaddition/retroelectrocyclization step (CA-RE). Several fluorenyl derivatives in addition to phenanthrenyl and terphenyl ones provided ynamide-based TCBDs affording remarkable emission properties covering a large range of wavelengths. Those compounds emit both in solid state and in solution from the visible region to the NIR range, depending on the molecular structures. Quantum yields in cyclohexane reached unforeseen values for such derivatives, up to 7.8 %. A huge sensitivity to the environment of the TCBDs has also been unraveled for most of the compounds since we observed a dramatic fall of the quantum yields when changing the solvent from cyclohexane to toluene, while they are almost non-emissive in dichloromethane.


Asunto(s)
Colorantes Fluorescentes , Reacción de Cicloadición , Colorantes Fluorescentes/química , Ionóforos , Estructura Molecular
4.
Phys Chem Chem Phys ; 23(39): 22283-22297, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34585692

RESUMEN

The synthesis and characterization of four new tetracyanobutadiene (TCBD) derivatives (1, 3c and 4b-c) incorporating tosylamido and 4-triphenylamino moieties are reported. Along with those of five closely related or differently branched TCBDs derivatives (2, 3a-b, 4c and 5), their linear and (third-order) nonlinear optical properties were investigated by electronic absorption spectroscopy and Z-scan measurements. Among these compounds, the tri-branched compounds 3c and 5 are the most active two-photon absorbers, with effective cross-sections of 275 and 350 GM at 900 nm, respectively. These properties are briefly discussed with the help of DFT calculations, focussing on structural and electronic factors, and contextualized with results obtained previously for related compounds.

5.
Molecules ; 25(22)2020 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-33238454

RESUMEN

The synthesis of four new 1,3,5-triaryl-1,3,5-triazinane-2,4,6-trithione derivatives (thioisocyanurates) and two new partially thionated analogues from the corresponding 1,3,5-triaryl-1,3,5-triazinane-2,4,6-triones (isocyanurates) is reported, together with their spectroscopic properties. DFT calculations and comparison with the corresponding isocyanurates evidence the impact of the oxygen-for-sulfur replacement on the electronic structure and linear optical properties of these heterocycles. A bathochromic shift of the absorption bands and more efficient quenching of the fluorescence was observed.


Asunto(s)
Triazinas/química , Técnicas de Química Sintética , Teoría Funcional de la Densidad , Modelos Teóricos , Estructura Molecular , Fenómenos Ópticos , Análisis Espectral , Triazinas/síntesis química
6.
Molecules ; 25(2)2020 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-31936003

RESUMEN

: A series of free base and Zn(II) phthalocyanines featuring fluorenyl antennae linked by methoxy or oxo bridges to the phthalocyanine core (Pc) were synthesized and characterized. Selected linear and nonlinear (two-photon absorption) optical properties of these new compounds were subsequently studied. As previously observed for related porphyrin dendrimers bearing 2-fluorenyl peripheral dendrons, an efficient energy transfer occurs from the peripheral antennae to the central phthalocyanine core following excitation in the fluorenyl-based π-π* absorption band of these chromophores. Once excited, these compounds relax to the ground state, mostly by emitting intense red light or by undergoing intersystem crossing. As a result, the tetrafunctionalized Zn(II) phthalocyanines are fluorescent, but can also efficiently photosensitize molecular oxygen in tetrahydrofurane (THF), forming singlet oxygen with nearly comparable yields to bare Zn(II) phthalocyanine (ZnPc). In comparison with the latter complex, the positive role of the fluorenyl-containing antennae on one- and two-photon brightness (2PA) is presently demonstrated when appended in peripheral (ß) position to the phthalocyanine core. Furthermore, when compared to known porphyrin analogues, the interest in replacing the porphyrin by a phthalocyanine as the central core to obtain more fluorescent two-photon oxygen photosensitizers is clearly established. As such, this contribution paves the way for the future development of innovative biphotonic photosensitizers usable in theranostics.


Asunto(s)
Fluorenos/química , Indoles/química , Fármacos Fotosensibilizantes/química , Oxígeno Singlete/química , Transferencia de Energía , Fluorenos/síntesis química , Indoles/síntesis química , Isoindoles , Luz , Luminiscencia , Modelos Moleculares , Estructura Molecular , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/química , Fotones , Porfirinas/química , Oxígeno Singlete/aislamiento & purificación , Análisis Espectral
7.
Subst Use Misuse ; 54(5): 841-851, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30648459

RESUMEN

BACKGROUND: Stressful deployments in combat areas are known to increase the risk of substance abuse in military personnel. OBJECTIVES: The aim of the study was to compare deployment on stressful, high-intensity missions (HIMs) to deployment on low-intensity missions (LIMs) in order to understand factors associated with substance use variations across the mission. METHODS: A retrospective cohort study based on a one-shot self-questionnaire was performed four months after their return on two samples of male French Army service members: one returning from an HIM and one from an LIM. The questionnaire focused on tobacco, alcohol, cannabis, cocaine, and psychoactive medication use at three times: before, during, and after the mission. RESULTS: During an HIM, the frequency of tobacco use increased, alcohol use remained stable - although 38% declared a decrease in consumption - and illicit drug use decreased. During an LIM, tobacco and alcohol use increased, cannabis use remained stable, and only cocaine and medication use decreased. After their return, use levels among both samples reverted to values similar to those reported before the mission, except for a decrease in tobacco use observed at return from an HIM. The main factors perceived as related to variations were stress in an HIM and low cost in an LIM. Conclusions/importance: The study suggests a differential impact of deployment on substance use according to the operational intensity of the mission. Variations in use are predominant during the mission with a washout effect after returning home.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Trastornos Relacionados con Sustancias/diagnóstico , Uso de Tabaco/psicología , Adulto , Estudios de Cohortes , Humanos , Masculino , Personal Militar/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo , Trastornos Relacionados con Sustancias/psicología , Encuestas y Cuestionarios , Adulto Joven
8.
Chemistry ; 23(11): 2635-2647, 2017 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-27976827

RESUMEN

A series of three conjugated meso-porphyrin dendrimers containing conjugated dendrons featuring 2,7-fluorenyl groups, incorporating overall 8, 12, or 28 fluorenyl units have been synthesized and characterized. The photophysical properties of these new compounds were studied in the context of photodynamic therapy. The relevant linear and nonlinear optical properties were measured in organic media and useful structure-properties relationships were derived.

9.
Chemistry ; 22(16): 5583-97, 2016 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-26933931

RESUMEN

A new family of conjugated meso-tetraphenylporphyrin-based dendrimers with four (TPP1, TPP2), eight (TPP3, TPP4, TPP5) and up to sixteen (TPP6) fluorenyl groups has been synthesized and fully characterized. These tetraphenylporphyrin-cored dendrimers present peripheral alkynyl π-conjugated dendrons with fluorenyl termini. The meso-aryl rings of these porphyrins are functionalized either in para- (TPP1, TPP2, and TPP3) or meta-positions (TPP4, TPP5, and TPP6). Their detailed luminescence properties are discussed in reference to two porphyrins lacking fluorenyl dendrons (TPP-H1,2,3 and TPP-H4,5,6). A strong dependence of their luminescence quantum yield and lifetime on their structures is stated, their nonlinear optical properties were also discussed.

10.
Chemistry ; 22(29): 10155-67, 2016 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-27297358

RESUMEN

The synthesis and characterization of four new tetracyanobutadiene (TCBD) derivatives (1-3 and 2') incorporating 2- or 2,7-fluorenyl and diphenylamino moieties are reported. The electroactivity of 1-3 and 2' was studied by cyclic voltammetry (CV), while the linear optical and (third-order) nonlinear optical (NLO) properties were investigated by electronic spectroscopy and Z-scan studies, respectively. All experimental investigations were rationalized by DFT computations, providing an insight into the electronic structure of these derivatives and on their application potential. We show that these derivatives are nonluminescent in solution at ambient temperatures, but become fluorescent in solvent glasses. This finding constitutes an unprecedented observation for TCBD derivatives. Also, we show by Z-scan studies that these derivatives behave as two-photon absorbers in the near-IR range (800-1050 nm). These third-order NLO properties are discussed and compared with those of their alkynyl precursors (4-6), which have been investigated by two-photon excited fluorescence (TPEF).

11.
Angew Chem Int Ed Engl ; 55(28): 8062-6, 2016 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-27193483

RESUMEN

The combination of a bis-alkynyl-helicene moiety with two iron centers leads to novel electroactive species displaying unprecedented redox-triggered chiroptical switching. Upon oxidation, strong changes of vibrational modes (either local or extended coupled modes) are detected by vibrational circular dichroism and Raman optical activity. Remarkably, the sign of the optical rotation at 1.54 µm (that is, at wavelengths typically used for telecommunications) changes upon oxidation while the topology and stereochemistry of the helicene remain unchanged.

12.
Inorg Chem ; 52(15): 8993-9004, 2013 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-23869668

RESUMEN

The synthesis of four triaylphosphine ligands featuring electron-rich Fe(II) "Fe(κ(2)-dppe)(η(5)-C5Me5)C≡C-" pendant substituents in para and meta position(s) (1-4) is reported along with that of their corresponding radical cations (1-2[PF6] or 3-4[PF6]3). These triarylphosphines possessing redox-active organometallic substituents constitute a new class of phosphorus-based metallo-ligands. In contrast to many related ferrocenylphosphines, these metallo-ligands are stable and isolable in two redox-states. Their steric and electronic properties are also briefly discussed.

13.
Integr Psychol Behav Sci ; 57(4): 1183-1197, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36683120

RESUMEN

In the following article, I will briefly introduce the method of Allegory Analysis (AA) (Guenther, 2020, 2021, in press) and then outline it in its application to the case study of. The goal of this article is to introduce AA and illustrate it using the particularly illustrative case of Theresa. It will be shown how AA can be a new psychotherapeutic method in the therapist's toolbox, with which the human psyche in its individual uniqueness can be understood in the clinical context through creative means. Allegories of patients are defined here as complex linguistic constructs of multiple metaphors and as expressions of complex affective perception and experience. In order to understand a human psyche through its allegories, AA proceeds in four steps: (1) picking up and describing the allegories, (2) summarizing them into a so-called allegory poem, (3) interpreting the allegories on the part of the therapist, and (4) participatory interpretation of the allegories with the patient. The present case of Theresa illustrates the application of the AA method in an outpatient psychotherapeutic context and shows how through AA. In Theresa's case, the client was found to be ideologically guided by values such as autonomy, freedom, honesty, sustainability, charity, and connectedness. Her psychosis represented an autopoietic self-healing attempt to recover these values, which had been inaccessible to her in the antecedent process. The AA showed that Theresa believes that crises in the market economy, interpersonal coexistence, and climate change are at a critical point that threatens the existence of the world and thus her psychological stability. Moreover, in Theresa's allegories, it is evident that she had managed to use her values and beliefs autopoietically to stabilize her crisis through her coping strategy: externalization through poetic-allegorical language.


Asunto(s)
Relaciones Profesional-Paciente , Psicoterapia , Femenino , Humanos
14.
Mil Med ; 188(9-10): 3182-3190, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-35472134

RESUMEN

INTRODUCTION: In the military population, trauma-related nightmares (TRNs) are highly associated with deployments and combat-related events. Trauma-related nightmares are also correlated with severity, treatment resistance, and chronicity of Post-Traumatic Stress Disorder (PTSD). However, to date, no specific measure of TRNs has been validated for use in the French language. This study aimed to translate and culturally adapt the English version of the Trauma-Related Nightmare Survey into French and to evaluate the psychometric properties of the translation on veterans. MATERIALS AND METHODS: After the translation and cultural adaptation process, we evaluated the reliability and validity of the French version of the questionnaire (TRNS-FR) in a population of veterans suffering from PTSD with nightmare complaints (n = 56 patients for test-retest and n = 60 for internal consistency), recruited from five French military hospitals. RESULTS: Analyses demonstrated that TRNS-FR has good test-retest reliability (r = 0.59) and good internal consistency with PTSD symptoms, insomnia symptoms, and subjective sleep parameters assessed at home. This questionnaire provides a rapid and comprehensive assessment of sleep disturbance and a specific description of TRNs in the population of veterans with severe PTSD. Our results allowed us to propose a valid and reliable French adaptation of the questionnaire. CONCLUSION: Because sleep disturbances and TRNs require specific therapeutic management, the psychometric qualities of TRNS-FR make it a tool of choice for assessing TRNs in future clinical research settings.


Asunto(s)
Sueños , Disomnias , Trastornos por Estrés Postraumático , Adulto , Femenino , Masculino , Persona de Mediana Edad , Comparación Transcultural , Disomnias/diagnóstico , Disomnias/etiología , Francia , Psicometría , Trastornos por Estrés Postraumático/complicaciones , Encuestas y Cuestionarios , Traducciones , Veteranos , Humanos
15.
Animals (Basel) ; 13(12)2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37370478

RESUMEN

Gaining insights into the utilization of farm-level data for decision-making within the beef industry is vital for improving production and profitability. In this study, we present a statistical model to predict the carcass weight (CW) of grass-fed beef cattle at different stages before slaughter using historical cattle data. Models were developed using two approaches: boosted regression trees and multiple linear regression. A sample of 2995 grass-fed beef cattle from 3 major properties in Northern Australia was used in the modeling. Four timespans prior to the slaughter, i.e., 1 month, 3 months, 9-10 months, and at weaning, were considered in the predictive modelling. Seven predictors, i.e., weaning weight, weight gain since weaning to each stage before slaughter, time since weaning to each stage before slaughter, breed, sex, weaning season (wet and dry), and property, were used as the potential predictors of the CW. To assess the predictive performance in each scenario, a test set which was not used to train the models was utilized. The results showed that the CW of the cattle was strongly associated with the animal's body weight at each stage before slaughter. The results showed that the CW can be predicted with a mean absolute percentage error (MAPE) of 4% (~12-16 kg) at three months before slaughter. The predictive error increased gradually when moving away from the slaughter date, e.g., the prediction error at weaning was ~8% (~20-25 kg). The overall predictive performances of the two statistical approaches was approximately similar, and neither of the models substantially outperformed each other. Predicting the CW in advance of slaughter may allow farmers to adequately prepare for forthcoming needs at the farm level, such as changing husbandry practices, control inventory, and estimate price return, thus allowing them to maximize the profitability of the industry.

16.
Chemistry ; 18(37): 11811-27, 2012 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-22829537

RESUMEN

The linear optical (LO) and nonlinear optical (NLO) properties of a series of isocyanurates functionalized by donor arms at the periphery are reported herein. These octupolar derivatives were obtained in a straightforward way from commercial isocyanate derivatives and were fully characterized. Although several of these compounds are known, those that exhibited the largest NLO activities are all new compounds. In terms of second-order activity, several of these derivatives exhibit remarkable activity/transparency tradeoffs. In terms of third-order activity, the longer derivatives with the stronger donor groups (X = NH(2), NMe(2), or NPh(2)) were shown to possess significant two-photon absorption cross sections. These strongly luminescent derivatives exhibit two-photon absorption cross sections up to 410 GM. DFT computations were also conducted to unravel their electronic structures and to rationalize their NLO properties. To our knowledge, the present study is the first concerned with the nonlinear optical properties of these original cyclotrimers.


Asunto(s)
Isocianatos/química , Triazinas/química , Modelos Moleculares , Estructura Molecular , Teoría Cuántica , Estereoisomerismo
17.
Cancers (Basel) ; 14(10)2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35625963

RESUMEN

Star-shaped hydrophobic porphyrins, acting as powerful fluorescent two-photon photosensitizers for oxygen in organic solvents, can easily be loaded into PMLABe polymeric nanoparticles at various concentrations. In this contribution, the performance of these porphyrin-containing nanoparticles in terms of photodynamic therapy (PDT) is compared to those of the corresponding water-soluble porphyrin analogues when irradiated in MCF-7 cancer cells. While quite promising results are obtained for performing PDT with these nanoparticles, validating this approach as a mean for using more easily accessible and less expensive photosensitizers, from a synthetic perspective, we also show that their luminescence can still be used for bioimaging purposes in spite of their confinement in the nanoparticles, validating also the use of these nano-objects for theranostic purposes.

18.
Chemistry ; 17(20): 5561-77, 2011 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-21495098

RESUMEN

The new [(η(2)-dppe)(η(5)-C(5)Me(5))Fe(C≡C-1,4-C(6)H(4)C≡C)Ru(η(2) -dppe)(2) C≡C(C(6)H(5))] complex (3-H) and its hexanuclear relative [{(η(2)-dppe)(η(5)-C(5) Me(5))Fe(C≡C-1,4-C(6)H(4)-C≡C)Ru(η(2)-dppe)(2)(C≡C-1,4-C(6)H(4)C≡C)(3)(1,3,5-C(6)H(3))] (4) have been synthesized and characterized. The linear and cubic nonlinear optical properties of these compounds in their various redox states have been studied along with those of the analogous complexes [(η(2)-dppe)(η(5)-C(5)Me(5))Fe(C≡C-1,4-C(6)H(4)C≡C)Ru(η(2)-dppe)(2)R][PF(6)](n) (n=0-2; R=Cl, 2-Cl; R=C≡C(4-C(6)H(4)NO(2)),3-NO(2)). We show that molecules exhibiting large third-order nonlinearities can be obtained by assembling such dinuclear Fe/Ru units around a central 1,3,5-substituted C(6)H(3) core. These data are discussed with a particular emphasis on the large changes in their nonlinear (third-order) optical properties brought about by oxidation. Experimental and computational (DFT) evidence for the electronic structures of these compounds in their various redox states is presented using 3-H(n+) as a prototypical model. Single crystals of this complex in its mono-oxidized state (3-H[PF(6)]) provide the first structural data for such carbon-rich Fe(III) /Ru(II) heteronuclear mixed-valent (MV) systems. Although experimental evidence for the structure of the dioxidized states was more difficult to obtain, the theoretical study reveals that 3-H(2+) can be considered to have a biradical structure with two independent spins. The low-lying absorptions that appear in the near-infrared (NIR) range for all these compounds following oxidation correspond to intervalence charge-transfer (IVCT) bands for the mono-oxidized states and to ligand-to-metal charge-transfer (LMCT) transitions for the dioxidized states. These play a crucial role in the strong optical modulation achieved. The possibility of accessing additional states with distinct linear or nonlinear optical properties is also briefly discussed.

19.
Inorg Chem ; 50(24): 12601-22, 2011 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-22070368

RESUMEN

The role of the nitrogen atom on the electronic and magnetic couplings of the mono-oxidized and bi-oxidized pyridine-containing complex models [2,6-{Cp(dpe)Fe-C≡C-}(2)(NC(5)H(3))](n+) and [3,5-{Cp(dpe)Fe-C≡C-}(2)(NC(5)H(3))](n+) is theoretically tackled with the aid of density-functional theory (DFT) and multireference configuration interaction (MR-CI) calculations. Results are analyzed and compared to those obtained for the reference complex [1,3-{Cp*(dppe)Fe-C≡C-)}(2)(C(6)H(4))](n+). The mono-oxidized species show an interesting behavior at the borderline between spin localization and delocalization and one through-bond communication path among the two involving the central ring, is favored. Investigation of the spin state of the dicationic complexes indicates ferromagnetic coupling, which can differ in magnitude from one complex to the other. Very importantly, electronic and magnetic properties of these species strongly depend not only upon the location of the nitrogen atom in the ring versus that of the organometallic end-groups but also upon the architectural arrangement of one terminus, with respect to the other and/or vis-à-vis the central ring. To help validate the theoretical results, the related families of compounds [1,3-{Cp*(dppe)Fe-C≡C-)}(2)(C(6)H(4))](n+), [2,6-{Cp*(dppe)Fe-C≡C-}(2)(NC(5)H(3))](n+), [3,5-{Cp*(dppe)Fe-C≡C-}(2)(NC(5)H(3))](n+) (n = 0-2) were experimentally synthesized and characterized. Electrochemical, spectroscopic (infrared (IR), Mössbauer), electronic (near-infrared (NIR)), and magnetic properties (electron paramagnetic resonance (EPR), superconducting quantum interference device (SQUID)) are discussed and interpreted in the light of the theoretical data. The set of data obtained allows for many strong conclusions to be drawn. A N atom in the long branch increases the ferromagnetic interaction between the two Fe(III) spin carriers (J > 500 cm(-1)), whereas, when placed in the short branch, it dramatically reduces the magnetic exchange in the di-oxidized species (J = 2.14(5) cm(-1)). In the mixed-valence compounds, when the N atom is positioned on the long branch, the intermediate excited state is higher in energy than the different ground-state conformers and the relaxation process provides exclusively the Fe(II)/Fe(III) localized system (H(ab) ≠ 0). Positioning the N atom on the short branch modifies the energy profile and the diabatic mediating state lies just above the reactant and product diabatic states. Consequently, the LMCT transition becomes less energetic than the MMCT transition. Here, the direct coupling does not occur (H(ab) = 0) and only the coupling through the bridge (c) and the reactant (a) and product (b) diabatic states is operating (H(ac) = H(bc) ≠ 0).

20.
Mil Med ; 176(7): 805-10, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22128723

RESUMEN

OBJECTIVE: To ascertain the different profiles of alcohol and cannabis consumers in the French Army to improve prevention measures. METHOD: A representative sample of 990 French Army staff filled in self-questionnaires in 2006. A multiple correspondence analysis identified associations between consumption and consumer profiles. RESULTS: The multiple correspondence analysis found three main consumer profiles: non-consumers (women and officers), moderate consumers (non-commissioned officers > 30-years old, single parents with children), and occasional multi-consumers (18-25-years-old enlisted males, who occasionally consumed cannabis and high levels of alcohol, also tobacco-addicts). Two minor profiles emerged: daily alcohol drinkers (men, > or = 30 years) and regular dependent cannabis users (identical profile to multi-consumers). CONCLUSION: Our results favor targeting the youngest to prevent the risks of high alcohol intake and cannabis consumption and addiction linked to repeated binge drinking. Systematic questionnaires on consumption habits and addiction self-evaluations during medical consultations could lead to early care.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Fumar Marihuana/epidemiología , Personal Militar/estadística & datos numéricos , Adulto , Alcoholismo/epidemiología , Femenino , Francia , Humanos , Masculino , Abuso de Marihuana/epidemiología , Fumar/epidemiología , Encuestas y Cuestionarios , Adulto Joven
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