Electronic structure with spin-orbit coupling effect of HfH molecule for laser cooling investigations.

The electronic structure, including the spin-orbit coupling effect of the HfH molecule, has been studied to determine if it can be cooled through Doppler and Sysphus laser cooling techniques. The multi-reference configuration interaction plus Davidson correction (MRCI + Q) method has been used to calculate its potential energy curves (P.E.C.s) in the Ω(±) and 2s+1Ʌ(+/-) representation. The spectroscopic constants Te, Re, ωe, Be, αe, the dipole moment µe, and the dissociation energies De agree very well with previously published work. In addition, we present in this work twenty new doublet and quartet states in the Ω(±) representation. The electronic transition dipole moment curves (TDMCs) between the lowest-lying electronic states have been investigated for the Δ - Π, Π - ∑+ and Δ - Φ transitions among specific Ω(±) states. The Franck-Condon factors (FCFs), the Einstein coefficient of spontaneous emission [Formula: see text] , and the radiative lifetime τ have been computed for the investigated transitions. In addition, properties of the molecules' electronic and vibrational states, such as the static dipole moment curves (D.M.C.s), the ionic character fionic, and the rovibrational constants are calculated. We deduce from our results that the HfH molecule is indeed a laser-cooling candidate that can reach a temperature as low as the nK regime. We present a complementary scheme with suitable experimental parameters. These results can be of great interest to experimental spectroscopists interested in ultracold diatomic molecules and their applications.

Significance of Vibronic Coupling that Shapes Circularly Polarized Luminescence of Double Helicenes.

The circularly polarized luminescence (CPL) spectra of S- and X-shaped double helicenes exhibit distinct vibrational structures and overall shape variations. In this study, we conducted an in-depth investigation into the vibronic effects influencing the CPL spectra of two double helicenes, namely DPC and DNH. Employing state-of-the-art computations utilizing the FC-HT1|VH model at the CAM-B3LYP/def2-TZVP level, we unveiled the paramount impact of Franck-Condon (FC), Herzberg-Teller (HT), and Duschinsky effects on their chiroptical responses. Our research underscores the pivotal role of structural deformations associated with the S1-to-S0 electronic transition in molding CPL spectra and wavelength-dependent dissymmetry (g) factor values, as well as the significance of HT effects in shaping and enhancing CPL responses. This extensive investigation not only advances our comprehension of the vibronic characteristics in configurationally distinct double helicenes but also offers valuable insights for the design of chiral molecules featuring controllable or finely-tunable CPL responses.

Unraveling the Origin of Long-Lifetime Emission in Low-Dimensional Copper Halides via a Magneto-optical Study.

The origin of the long lifetime of self-trapped exciton emission in low-dimensional copper halides is currently the subject of extensive debate. In this study, we address this issue in a prototypical zero-dimensional copper halide, Cs2(C18)2Cu2I4-DMSO, through magneto-optical studies at low temperatures down to 0.2 K. Our results exclude spin-forbidden dark states and indirect phonon-assisted recombination as the origin of the long photoluminescence lifetime. Instead, we propose that the minimal Franck-Condon factor of the radiative transition from excited states to the ground state is the decisive factor, based on the transition probability analysis. Our findings offer insights into the electronic processes in low-dimensional copper halides and have the potential to advance the application of these distinctive materials in optoelectronics.

Adesão ao preservativo masculino: realidade comportamental e conhecimento de universitários / Adherence to the male condom: behavioral reality and knowledge of university students

Homens e mulheres saberem a função do preservativo na prevenção de Infecções Sexualmente Transmissíveis e gravidez, várias situações dificultam o seu uso, entre elas, a ideia de que o preservativo interfere no prazer. OBJETIVO: Descrever o conhecimento e comportamentos de universitários sobre a adesão ao preservativo masculino. METODO-LOGIA: Estudo exploratório descritivo, quantitativo, com 136 estudantes de uma Universidade Pública. RESULTADOS: A média de idade foi de 20 anos, maior parte são heterossexuais (76,5%); a maioria teve a primeira relação sexual aos 17 anos, sendo que 33,5% não usaram camisinha, 85% utilizam camisinha para evitar gravidez, 92,5% para prevenção de Infecções Sexualmente Transmissíveis, 48,5% deixaram de ter relação sexual com penetração por não ter preservativo; 84% não utilizaram por não conseguir colocar e 54% tinham camisinha e não utilizou. CONCLUSÃO: Evidenciou a necessidade de repensar a educação sexual para instrumentalizar quanto a percepção, comportamento e adesão ao preservativo.(AU)

Men and women recognize condoms' role in preventing both Sexually Transmitted Infec-tions and pregnancy. However, various obstacles, such as concerns about reduced pleasure, impede their use. OBJECTIVE: To describe the knowledge and behaviors of university students regarding adherence to male condoms. METHODOLOGY: This was a descriptive, quantitative exploratory study involving 136 students from a public university. RESULTS: The average age was 20 years, with most identifying as heterosexual (76.5%). A significant portion (33.5%) did not use condoms. Furthermore, 85% used con-doms for pregnancy prevention, 92.5% for Sexually Transmitted Infections prevention, while 48.5% ceased sexual activity due to a lack of condoms. Additionally, 84% faced challenges with putting on condoms, and 54% possessed unused condoms. CONCLU-SION: These findings highlight the necessity to reevaluate sex education, providing indi-viduals with the tools to comprehend, modify their behavior, and enhance adherence to condom usage.(AU)

Hombres y mujeres conocen el papel del condón en la prevención de las Infecciones de Transmisión Sexual y el embarazo, varias situaciones dificultan su uso, entre ellas la idea de que el condón interfiere con el placer. OBJETIVO: Describir los conocimientos y comportamientos de estudiantes universitarios respecto de la adherencia al condón masculino. METODOLOGÍA: Estudio descriptivo, cuantitativo, exploratorio con 136 estudiantes de una Universidad Pública. RESULTADOS: La edad promedio fue de 20 años, la mayoría son heterosexuales (76,5%); la mayoría tuvo su primera relación sexual a los 17 años, el 33.5% no utilizó condón, el 85% utilizó condón para evitar el embarazo, el 92.5% para prevenir Infecciones de Transmisión Sexual, el 48.5% dejó de tener relaciones sexuales con penetración debido a no tener condón; El 84% no lo usó porque no pudo colocarlo y el 54% tenía condón pero no lo usó. CONCLUSIÓN: Se destacó la necesidad de repensar la educación sexual para brindar herramientas sobre percepción, comportamiento y adherencia al uso del condón.(AU)

Spectral Behavior of a Conjugated Polymer MDMO-PPV Doped with ZnO Nanoparticles: Thin Films.

The purpose of the presented study is to examine the impact of zinc oxide nanoparticles (ZnO NPs) on the spectrum features of poly [2-methoxy-5-(3',7'-dimethyloctyloxy)-1, 4-phenylenevinylene] (MDMO-PPV). The characteristics of the MDMO-PPV and doped ZnO NPS samples were assessed using several techniques. A set of solutions of MDMO-PPV in toluene that were doped with different ratio percentages of ZnO NPs was prepared to obtain thin films. Pristine and composite solutions were spin-coated on glass substrates. It was observed that MDMO-PPV had two distinct absorbance bands at 310 and 500 nm in its absorption spectrum. The UV-Vis spectrum was dramatically changed when 5% of ZnO NPs were added. The result showed a significant reduction in absorption of the band 500 nm, while 310 nm absorption increased rapidly and became more pronounced. Upon adding (10%) ZnONPs to the sample, no noticeable change was observed in the 500 nm band. However, the 310 nm band shifted towards the blue region. There is a dominant peak in the PL spectrum of MDMO-PPV in its pristine form around 575 nm and a smaller hump around 600 nm of the spectrum. The spectral profile at 600 nm and the intensity of both bands are improved by raising the ZnO NP concentration. These bands feature two vibronic transitions identified as (0-0) and (0-1). When the dopant concentration increased to the maximum dopant percentage (10%), the energy band gap values increased by 0.21 eV compared to the pristine MDMO-PPV. In addition, the refractive index (n) decreased to its lowest value of 2.30 with the presence of concentrations of ZnO NPs.

Association between HIV Perceived Risk and Intimate Partner Violence among Women / Asociación entre Percepción de Riesgo de VIH y Violencia de Pareja en Mujeres

Abstract HIV risk perception and Intimate partner violence (IPV) are related to HIV infection in women. However, there is a lack of information regarding on the association between risk perception and IPV in the Mexican population. This study aimed to identify and characterize subgroups based on their risk perception through the analysis of latent classes and to evaluate the variables associated with HIV risk perception. An online survey was conducted to assess sexual and preventive behavior, HIV risk perception, and intimate partner violence. Three hundred thirty-two women participated; the sampling was for convenience. Two latent classes were identified: a group with risk perception (85%) and one without risk perception (14.6%). The variables associated with the risk perception were a sexual attraction to men, not having a stable partner, perceiving oneself as at risk of acquiring HIV due to sexual behavior, and the presence of IPV. HIV prevention programs for women must address the stigmas related to HIV, such as the idea that the risk only occurs when they have multiple sexual partners, promote accurate HIV risk perception and prevent IPV in all its expressions and contexts.

Resumen En mujeres, la violencia de pareja está relacionada a una mayor probabilidad de adquirir la infección por VIH. De igual forma, una inadecuada percepción de riesgo de adquirir el virus coloca a las mujeres en una situación vulnerable. Existe una falta de información ente la asociación de la VPI y la percepción de riesgo es mujeres mexicanas. Este estudio persiguió dos objetivos: el primero fue identificar y caracterizar subgrupos en función de su percepción de riesgo a través del análisis de clases latentes; el segundo objetivo consistió en evaluar las variables asociadas con la percepción de riesgo de VIH. Se realizó una encuesta en línea para evaluar el comportamiento sexual y preventivo, la percepción del riesgo de VIH y la VP. Participaron 332 mujeres; el muestreo fue por conveniencia. Se identificaron dos clases latentes: un grupo con percepción de riesgo (85%) y otro sin percepción de riesgo (14,6%). Las variables asociadas a la percepción de riesgo fueron atracción sexual por hombres, no tener pareja estable, percibirse en riesgo de adquirir el VIH por la conducta sexual y haber sufrido de violencia de pareja en los últimos seis meses. Se concluye que los programas de prevención del VIH para mujeres deben abordar los estigmas relacionados con el VIH, como la idea de que el riesgo solo ocurre cuando tienen múltiples parejas sexuales, promover una percepción precisa del riesgo del VIH y principalmente, prevenir la VP en todas sus expresiones y contextos; así como también dar atención personalizada a mujeres que ya sufren de violencia de pareja.

Balance decisional sobre el uso del condón asociado a la conducta sexual de riesgo en universitarios / Decisional balance of condom use associated with risky sexual behavior in university students

Resumen La adquisición de alguna Infección de Transmisión Sexual (ITS) y los embarazos no planificados son riesgos a los que se enfrentan los jóvenes ante la decisión de no usar condón al tener relaciones sexuales. La aproximación del balance decisional enfatiza qué costos y beneficios están asociados a la conducta sexual de riesgo. Las decisiones acerca del uso del condón son un precursor de la conducta y este proceso puede estar influido por los beneficios que se perciban sobre él. El objetivo de la presente investigación es identificar la relación de las ganancias y pérdidas del uso del condón con la conducta sexual de riesgo. Se evaluó la conducta sexual de riesgo y el uso del condón masculino en sus relaciones sexuales. Se midieron las ganancias y las pérdidas del condón con una escala de medición, en una muestra de 257 universitarios, con una edad entre 18 y 39 años (. = 22.34; DE = 3.6) de Querétaro, México. La evaluación del balance decisional indica que las ganancias son mayores que las pérdidas (costos) del uso consistente del condón en las relaciones sexuales. Se encontraron asociaciones entre las ganancias y las pérdidas con indicadores de la conducta sexual de riesgo. Se observa que los universitarios que no utilizan condón manifiestan mayores pérdidas por utilizarlo. En las ganancias, se aprecia un aumento en las puntuaciones cuando se usa condón. Lo encontrado provee apoyo para el desarrollo de intervenciones que promuevan las ganancias o beneficios para incrementar el uso consistente del condón.

Abstract The acquisition of a Sexually Transmitted Infection (STI) and unplanned pregnancies are risks that young people deal when deciding not to use a condom when having sexual intercourse. During the decision-making process, individuals value the benefits (gains) and losses (costs) associated with a behavior. Cost-benefit analysis has been investigated to examine the differential impact of gains and losses on risky behaviours. The decisional balance approach emphasizes that costs and benefits are associated with risky sexual behavior. Decisions about condom use are a precursor to behavior, and this process may be influenced by perceived benefits. In the present study, it is proposed that the balance between the benefit and the loss of condom use contributes to consistent condom use. These factors as determinants of behaviour must be considered under the cultural context in which they are carried out. The objective of this research is to identify the relationship of gains and losses from condom use with risky sexual behaviour. It was hypothesized that: 1) Young people will evaluate the benefits (gains) with higher scores compared to the losses (costs) in deciding to use a condom in sexual intercourse. 2) The gains will be greater in those college students who use a condom more frequently and the losses will not be the same among those who use a condom. To evaluate risky sexual behavior and the use of the male condom in their sexual relations were considered. Condom gains and losses were measured with a measurement scale in a sample of 257 university students, aged between 18 and 39 years (. = 22.34; SD = 3.6) from Querétaro, México. With reference to sexual behavior, it was found that 89.1 % have started their sexual activity. The average age of initiation of sexual life is 15.41 years. The frequency of sexual activity is once or twice each month. The mean of sexual partners is 4.2, with a median of 3. The 68.5 % reported using some contraceptive method and regarding the use of condoms, 27.8 % always use it and 5.7 % never use it. To evaluate the decisional balance, subtracting the gain and loss factors created a net difference score. The gain factor was subtracted from its counterpart of the loss factor to indicate the preference for having sex with a condom. The decisional balance assessment indicates that the gains are greater than the losses (costs) of consistent condom use in sexual intercourse. Associations were found between gains and losses with indicators of risky sexual behavior. It is observed that university students who do not use a condom show greater losses from using it. In gains, there is an increase in scores when using a condom. Additionally, it is observed that university students, who sometimes use a condom, show greater losses for using it, unlike those who always use it, which show low scores in the losses of using it. In gains factor, there is an increase in the scores when using a condom, that is, those who never or almost never use a condom have the lowest scores and as the scores increase, the frequency of using a condom in their sexual relations also increases. In conclusion, gains and losses from male condom use are associated with risky sexual behavior (age of sexual activity, number of partners and condom use) in the university context. The findings provide support for the development of interventions that promote gains or benefits to increase consistent condom use. It is important to consider in specific interventions those young people who decide to continue having sex without using a condom despite the costs and possible consequences of not using it.

Vibronic and Cationic Features of 2-Fluorobenzonitrile and 3-Fluorobenzonitrile Studied by REMPI and MATI Spectroscopy and Franck-Condon Simulations.

Fluorinated organic compounds have superior physicochemical properties than general organic compounds due to the strong C-F single bond; they are widely used in medicine, biology, pesticides, and materials science. In order to gain a deeper understanding of the physicochemical properties of fluorinated organic compounds, fluorinated aromatic compounds have been investigated by various spectroscopic techniques. 2-fluorobenzonitrile and 3-fluorobenzonitrile are important fine chemical intermediates and their excited state S1 and cationic ground state D0 vibrational features remain unknown. In this paper, we used two-color resonance two photon ionization (2-color REMPI) and mass analyzed threshold ionization (MATI) spectroscopy to study S1 and D0 state vibrational features of 2-fluorobenzonitrile and 3-fluorobenzonitrile. The precise excitation energy (band origin) and adiabatic ionization energy were determined to be 36,028 ± 2 cm-1 and 78,650 ± 5 cm-1 for 2-fluorobenzonitrile and 35,989 ± 2 cm-1 and 78,873 ± 5 cm-1 for 3-fluorobenzonitrile, respectively. The density functional theory (DFT) at the levels of RB3LYP/aug-cc-pvtz, TD-B3LYP/aug-cc-pvtz, and UB3LYP/aug-cc-pvtz were used to calculate the stable structures and vibrational frequencies for the ground state S0, excited state S1, and cationic ground state D0, respectively. Franck-Condon spectral simulations for transitions of S1 ← S0 and D0 ← S1 were performed based on the above DFT calculations. The theoretical and experimental results were in good agreement. The observed vibrational features in S1 and D0 states were assigned according to the simulated spectra and the comparison with structurally similar molecules. Several experimental findings and molecular features were discussed in detail.

Discursos identificados sobre el uso y no uso del condón en hombres gais, bisexuales y otros hombres que tienen sexo con hombres en dos ciudades de Colombia / Discourses about condom use and non-use among gay, bisexual men, and other men who have sex with men in two colombian cities

FUNDAMENTOS: El aumento de casos de VIH suscita preocupación a nivel mundial. Este fenómeno se relaciona, entre otrascosas, con prácticas sexuales en donde se limita el uso del condón. Para lograr la erradicación del sida, organismos internacionalesse han interesado en analizar y comprender las prácticas sexuales de ciertos grupos poblacionales, dentro de estos, los hombresque tienen relaciones sexuales con otros hombres. En este sentido, el objetivo de este estudio fue analizar los discursos sobre el usoy no uso del condón que tenía un grupo de hombres gais, bisexuales y otros hombres que tienen sexo con hombres (GBHSH) de dosciudades de Colombia. MÉTODOS: Se realizó un estudio cualitativo con análisis de datos por medio del proceso iterativo, desde la interpretación delmodelo Información, Motivación y Habilidades conductuales (IMB, por sus siglas en inglés). La recolección de la información se realizóentre los años 2020 y 2021 por medio de entrevistas en profundidad, de manera virtual y presencial, con una muestra de 20 GBHSHde Colombia de las ciudades de Cali y Medellín. RESULTADOS: En el componenteInformación se identificó que la educación sexual tradicional tenía un impacto negativo y muyenfocado a una mirada cisheterosexual y reproductiva. Respecto a loMotivacional, se destacó que la mayoría se orientaban al nouso del condón y que percibir un bajo riesgo de contraer una ITS era la principal motivación del no uso del condón. Con relación alasHabilidades Conductuales se analizó que la desconfianza hacia la pareja sexual promovía su uso, pero la intensificación del placer,sumado al consumo de alcohol y drogas, hacía que su uso disminuyera. También se evidenció que el uso de fármacos como el PrePo el PEP desestimulaban el uso del condón en las relaciones.CONCLUSIONES: Lainformación sobre el uso del condón gira alrededor de prácticas cisheteronormativas, dejando de ladolos cuidados relacionados con las ITS...(AU)

BACKGROUND: The HIV increase cases raises concern worldwide. This phenomenon is related, among other things, to sexual practices where condom use is limited. To achieve the eradication of AIDS, international organizations have been interested in analyzingand understanding the sexual practices of certain population groups, within these men who have sex with other men. In this sense,the objective of this study was to analyze the discourses on the use and non-use of condoms held by a group of gay, bisexual andother men who have sex with men (GBHSH) men from two cities in Colombia.METHODS: A qualitative study was carried out with data analysis through the iterative process, from the interpretation of the Information, Motivation and Behavioral Skills (IMB) model. The collection of information was carried out between 2020 and 2021 through in-depthinterviews, virtually and in person, with a sample of 20 GBHSH from Colombia from the cities of Cali and Medellín. RESULTS: In theInformation component, it was identified that traditional sexual education had a negative impact and was veryfocused on a cisheterosexual and reproductive perspective. RegardingMotivational, it was highlighted that the majority were orientedtowards not using condoms and that perceiving a low risk of contracting an STI was the main motivation for not using condoms. RegardingBehavioral Skills, it was analyzed that distrust towards the sexual partner promoted its use, but the intensification of pleasure,added to the consumption of alcohol and drugs, caused its use to decrease. It was also evidenced that the use of drugs such as PrePor PEP discouraged condom use in relationships. CONCLUSIONS: Theinformation on condom use revolves around cisheteronormative practices, leaving aside the care related toSTIs. Themotivation for not using condoms revolves around misinformation, pleasure and trust in the couple, while the motivationfor condom use revolves around health care...(AU)

Vibrationally Resolved Inner-Shell Photoexcitation of the Molecular Anion C2.

Carbon 1s core-hole excitation of the molecular anion C2 - has been experimentally studied at high resolution by employing the photon-ion merged-beams technique at a synchrotron light source. The experimental cross section for photo-double-detachment shows a pronounced vibrational structure associated with 1 σ u → 3 σ g ${1\sigma _u \to 3\sigma _g }$ and 1 σ g → 1 π u ${1\sigma _g \to 1\pi _u }$ core excitations of the C2 - ground level and first excited level, respectively. A detailed Franck-Condon analysis reveals a strong contraction of the C2 - molecular anion by 0.2 Šupon this core photoexcitation. The associated change of the molecule's moment of inertia leads to a noticeable rotational broadening of the observed vibrational spectral features. This broadening is accounted for in the present analysis which provides the spectroscopic parameters of the C2 - 1 σ u - 1 3 σ g 2 2 Σ u + ${1\sigma _u^{ - 1} \,3\sigma _g^2 \;^2 \Sigma _u^ + }$ and 1 σ g - 1 3 σ g 2 2 Σ g + ${1\sigma _g^{ - 1} \,3\sigma _g^2 \;^2 \Sigma _g^ + }$ core-excited levels.

Conformational Structures of Neutral and Cationic Pivaldehyde Revealed by IR-Resonant VUV-MATI Mass Spectroscopy.

Pivaldehyde, which is an unwanted by-product released with engine exhaust, has received considerable research attention because of its hydrocarbon oxidations at atmospheric temperature. To gain insight into the conformer-specific reaction dynamics, we investigated the conformational structures of the pivaldehyde molecule in neutral (S0) and cationic (D0) states using the recently invented IR-resonant VUV-MATI mass spectroscopy. Additionally, we constructed the two-dimensional potential energy surfaces (2D PESs) associated with the conformational transformations in the S0 and D0 states to deduce the conformations corresponding to the measured vibrational spectra. The 2D PESs indicated the presence of only the eclipsed conformation in the global minima of both states, unlike those in propanal and isobutanal. However, comparing the IR-dip VUV-MATI spectra from two intense peaks in the VUV-MATI spectrum with the anharmonic IR simulations revealed the correspondence between the gauche conformer on the S0 state and the measured IR spectra. Furthermore, Franck-Condon analysis confirmed that most peaks in the VUV-MATI spectrum are attributed to the adiabatic ionic transitions between the neutral gauche and cationic eclipsed conformers in pivaldehyde. Consequently, electron removal from the highest occupied molecular orbital, consisting of the nonbonding orbital of the oxygen atom in pivaldehyde, promoted the formyl-relevant modes in the induced cationic eclipsed conformer.

Production of ultracold polyatomic molecules with strong polarity by laser cooling: A detailed theoretical study on CaNC and SrNC.

Laser cooling molecules to the ultracold regime is the prerequisite for many novel science and technologies. It is desirable to take advantage of theoretical approaches to explore polyatomic molecular candidates, which are capable of being cooled to the ultracold regime. In this work, we explore two polyatomic candidates, CaNC and SrNC, which are suitable for laser cooling. These molecules possess impressively large permanent dipole moments (∼6 Debye), which is preferred for applications using an external electric field. High-level ab initio calculations are carried out to reveal electronic structures of these molecules, and the calculated spectroscopic constants agree very well with the available experimental data. For each molecule, the Franck-Condon factor matrix is calculated and shows a diagonal distribution. The radiative lifetimes for CaNC and SrNC are estimated to be 15.5 and 15.8 ns, respectively. Based upon the features of various electronic states and by choosing suitable spin-orbit states, we construct two feasible laser cooling schemes for the two molecules, each of which allows scattering nearly 10000 photons for direct laser cooling. These indicate that CaNC and SrNC are excellent ultracold polyatomic candidates with strong polarity.

Descuento temporal sexual en el comportamiento de riesgo en jóvenes / Temporary sexual discount on risky behaviour in young people

El propósito de la presente investigación es analizar el descuento temporalsexual en la conducta sexual de riesgo entre hombres y mujeres jóvenes. Seadministró la tarea de descuento temporal sexual del uso de condón con tressupuestos hipotéticos, así como un cuestionario para identificar sucomportamiento sexual de riesgo a 360 jóvenes, hombres y mujeres entre 16 y 33años de edad de México. Los resultados obtenidos indican adecuadaspropiedades psicométricas en a tarea de descuento sexual. Los hombres tienenuna menor demora en horas, días y meses para tener actividad sexual sin el usode condón en comparación con las mujeres. Para los hombres parece que eldescuento sexual es indiferente en su conducta sexual de riesgo. Las mujeresmostraron diferencias en el uso del condón y en el número de parejas sexuales,en dos de los tres tiempos de demora. Se espera contribuir en la comprensión deldescuento sexual para el desarrollo de intervenciones que promuevan unincremento del uso consistente del condón en jóvenes. (AU)

The purpose of this research is analyzing the sexual discount in risky sexualbehavior among young men and women. A condom sexual discounting task wasadministered with three hypothetical assumptions, as well as a questionnaire toidentify your risky sexual behavior in 360 youths, men and women between 16and 33 years old from Mexico. Men have a shorter delay in hours, days andmonths to have sexual activity without the use of a condom compared withwomen. For men sexual discount is indifferent to their risky sexual behavior. Thewomen showed differences in condom use and the number of sexual partners, intwo of the three delay conditions. These results may contribute to theunderstanding of sexual discount for interventions that promote an increase in condom use in young people. (AU)

Modeling the Electronic Absorption Spectra of the Indocarbocyanine Cy3.

Accurate modeling of optical spectra requires careful treatment of the molecular structures and vibronic, environmental, and thermal contributions. The accuracy of the computational methods used to simulate absorption spectra is limited by their ability to account for all the factors that affect the spectral shapes and energetics. The ensemble-based approaches are widely used to model the absorption spectra of molecules in the condensed-phase, and their performance is system dependent. The Franck-Condon approach is suitable for simulating high resolution spectra of rigid systems, and its accuracy is limited mainly by the harmonic approximation. In this work, the absorption spectrum of the widely used cyanine Cy3 is simulated using the ensemble approach via classical and quantum sampling, as well as, the Franck-Condon approach. The factors limiting the ensemble approaches, including the sampling and force field effects, are tested, while the vertical and adiabatic harmonic approximations of the Franck-Condon approach are also systematically examined. Our results show that all the vertical methods, including the ensemble approach, are not suitable to model the absorption spectrum of Cy3, and recommend the adiabatic methods as suitable approaches for the modeling of spectra with strong vibronic contributions. We find that the thermal effects, the low frequency modes, and the simultaneous vibrational excitations have prominent contributions to the Cy3 spectrum. The inclusion of the solvent stabilizes the energetics significantly, while its negligible effect on the spectral shapes aligns well with the experimental observations.

Factors associated with condom use behaviour among young university students / Fatores associados ao uso de camisinha entre jovens universitários / Factores asociados con el uso del condom entre jóvenes universitarios

As the rates of sexually transmitted infections among Brazilian youth rise, college students present with low rates of condom use. Understanding which factors affect preventive behaviours may assist in promoting them. This study aimed to test the Theory of Planned Behaviour (TPB) as a model of condom use behaviour among young university students. Data on sexual behaviour, TPB, and personality variables were collected online with 343 sexually active students aged between 18 and 29. Seventy participants also provided follow-up data after 30 days. Structural equation models and ordinal regressions were used to analyse the effects of TPB variables on condom use behaviour. Attitude was the main predictor of behavioural intention in the cross-sectional and longitudinal models. Being in a relationship and lower age at sexual debut were also associated with less frequent condom use behaviour in the cross-sectional analysis. Behavioural intention and perceived control were associated with condom use behaviour. (AU)

Enquanto a incidência de infecções sexualmente transmissíveis cresce entre jovens brasileiros, universitários apresentam pouco uso de preservativos. Compreender quais fatores afetam a adoção de comportamentos preventivos pode auxiliar na sua promoção. Esse estudo testou a Teoria do Comportamento Planejado (TCP) como modelo de uso de camisinha entre jovens universitários. Foram coletados dados sobre comportamento sexual, TCP, e personalidade em questionário online com 343 estudantes sexualmente ativos entre 18 e 29 anos de idade. Setenta participantes também responderam ao follow-up após 30 dias. Modelos de equações estruturais e regressões ordinais foram usados para analisar os efeitos das variáveis da TCP no uso de preservativo. Atitude foi o principal preditor da intenção comportamental nos modelos transversal e longitudinal. Estar em um relacionamento e menor idade na primeira relação sexual também foram associados a uso menos frequente de preservativo na análise transversal. Intenção comportamental e controle percebido foram associados com uso de preservativo. (AU)

Mientras la incidencia de infecciones de transmisión sexual aumenta entre los jóvenes brasileños, los estudiantes universitarios reportan poco uso de preservativos. Comprender qué factores inciden en la adopción de conductas preventivas puede ayudar en su promoción. Este estudio probó la Teoría del Comportamiento Planeado (TCP) como modelo de uso de preservativos entre jóvenes universitarios. Los datos sobre comportamiento sexual, TCP y personalidad fueron recopilados en un cuestionario en línea con 343 estudiantes sexualmente activos entre 18 y 29 años. Setenta participantes también respondieron al seguimiento después de 30 días. Se utilizaron modelos de ecuaciones estructurales y regresiones ordinales para analizar los efectos de las variables de TCP sobre la utilización del condón. La actitud fue el principal predictor de la intención en los modelos transversal y longitudinal. Estar en una relación y una edad más temprana en la primera relación sexual se asociaron con el uso menos frecuente de preservativo en el análisis transversal. La intención conductual y el control percibido se asociaron con el uso de condones. (AU)

Comportamento de adolescentes do sexo feminino acerca da utilização de preservativos / Comportamiento de adolescentes de sexo femenino ante el uso del condón / Behavior of female adolescents in the use of condoms

Objetivo: caracterizar o conhecimento e a prática acerca da utilização de preservativos por parte de adolescentes do sexo feminino, estudantes do ensino médio de uma escola da rede estadual do interior de Sergipe, Brasil. Materiais e método: pesquisa de corte transversal, realizada em uma escola da rede pública localizada no interior do Estado de Sergipe, Região Nordeste do Brasil. A coleta de dados ocorreu em fevereiro e março de 2017, na escola com o maior número de adolescentes matriculados do Estado. Resultados: entre as 94 participantes do estudo, a média de idade foi de 17,3 anos (DP = 1,2); a maioria das adolescentes referiu renda familiar mensal de até um salário-mínimo (61,3 %). A religião predominante foi a católica (74,5 %). Apenas 4,3 % das adolescentes afirmaram ter filho e uma delas encontrava-se gestante (1,1 %). Quanto à iniciação sexual, 51,1 % das adolescentes participantes referiram não ter tido as primeiras relações sexuais, enquanto 48,9 % apresentavam vida sexual ativa. A maior frequência de relações sexuais e uso de preservativo entre as adolescentes foi encontrada entre aquelas que referiram a ingesta de bebidas alcoólicas (40 [42,5 %]; p < 0,05). Sobre preservativos, 92,6 % das adolescentes conheciam e já haviam tido contato com o preservativo masculino, enquanto apenas 62,8 % conheciam e tinham visualizado o feminino. Conclusões: as adolescentes apresentam conhecimento frágil sobre preservativos e adotam prática sexual insegura; portanto, é fundamental o desenvolvimento de estratégias de educação sexual que visem melhorar o conhecimento e as habilidades das adolescentes sobre o tema.

Objetivo: caracterizar el conocimiento y la práctica en el uso del condón por parte de las estudiantes de secundaria de una escuela de la red pública del estado del interior de Sergipe, Brasil. Materiales y método: investigación transversal realizada en una escuela de la red pública ubicada en el interior del estado de Sergipe, región Nordeste de Brasil. La recolección de datos se llevó a cabo entre febrero y marzo de 2017 en las instalaciones de la institución educativa con mayor número de adolescentes matriculados del estado. Resultados: la edad media de las 94 participantes del estudio fue de 17,3 años (DP = 1,2), quienes en su mayoría reportaron un ingreso familiar mensual de hasta un salario mínimo (61,3 %). La religión predominante entre las participantes fue el catolicismo (74,5 %). Solo 4,3 % de las adolescentes afirmó tener un hijo y una de ellas (1,1 %) se encontraba en estado de embarazo al momento de la recolección de datos. En cuanto a la iniciación sexual, el 51,1 % de las participantes refirió no haber tenido su primera relación sexual, mientras que 48,9 % llevaba una vida sexual activa. La mayor frecuencia de relaciones sexuales y uso del condón fue identificada entre las adolescentes que reportaron la ingesta de bebidas alcohólicas (40 [42,5 %]; p< 0,05). Con respecto a los preservativos, 92,6 % de las adolescentes conocía y había tenido contacto con el condón masculino, mientras que solo el 62,8 % reportó lo mismo para el condón femenino. Conclusiones: las adolescentes que participaron de esta investigación tienen poco conocimiento sobre el condón y adoptan prácticas sexuales inseguras. Por ello, es fundamental desarrollar estrategias de educación sexual orientadas a mejorar los conocimientos y las habilidades de las adolescentes frente al tema.

Objective: To characterize the knowledge and practice regarding the use of condoms by high school female students from a public school in the state of Sergipe, Brazil. Materials and method: Cross-sectional research carried out at a public school in the state of Sergipe, northeastern Brazil. Data collection was performed between February and March 2017 at the school with the highest number of adolescents enrolled from the state. Results: The mean age among the 94 participants of the study was 17.3 years (SD: 1.2). Most adolescents reported a monthly family income of up to one minimum wage (61.3 %). The predominant religion in the sample was Catholicism (74.5 %). Only 4.3 % of these adolescents reported having a child and one of them was pregnant at the time of data collection (1.1 %). As for sexual initiation, 51.1 % of the participants reported they had not had their first sexual intercourse, while 48.9 % had an active sexual life. The highest frequency of sexual intercourse and condom use was found among those who reported alcohol consumption (40 [42.5 %]; p < 0.05). Finally, 92.6 % of the participants knew and had already visualized the male condom, while only 62.8 % stated the same for the female condom. Conclusions: The adolescents that participated in this study show a weak knowledge about condoms and adopt unsafe sexual practices. Therefore, it becomes essential to develop sexual education strategies aimed at improving the knowledge and skills regarding this issue among the studied population.

Spectroscopy and laser cooling of SiBr+: A computational perspective.

In the previous work, the SiBr+ cation is suggested as a candidate molecule for laser cooling, and in this work, on the basis of high-level ab initio calculation, the possibility of SiBr+ cation laser cooling is studied by considering the core-valence electrons correlations and spin-orbit coupling (SOC) effect. The potential energy curves of 12 Λ-S states and 36 Ω states considering SOC were obtained by using the multi-reference configuration interaction method and Davidson correction. Our computed results show that the Franck-Condon factor f00 for SiBr+ is only 0.619, which cannot guarantee that the number of the leaked photons is enough small, and more pumping laser beams are needed. Based on the calculated molecular properties, we discuss in detail the feasibility of laser cooling of SiBr+ and the results indicate that it is a challenge for laser cooling of SiBr+ .

Perception of Peer Condom Use Buffers the Associations Between HIV Knowledge, Self-efficacy, and Condom-Use Intention Among Adolescents: a Moderated Mediation Model.

A better understanding of the complex relationships between HIV knowledge, self-efficacy, perception of peer condom use, and condom-use intention is needed for improving HIV prevention among adolescents. The study analyzed survey data collected from high school students (N = 1970) in the Bahamas. Mediation and moderated mediation modeling analyses were used for data analysis. Results showed that self-efficacy mediated the association between HIV knowledge and condom-use intention. Perception of peer condom use moderated the mediation model by modifying the HIV knowledge-self-efficacy and self-efficacy-condom-use intention associations among males, but not for females. Findings of the study suggest the significant impact of perception of peer condom use in competition with HIV knowledge and self-efficacy in promoting condom use. Effective intervention program may consider targeting the modification of adolescents' perception of peer condom use to promote condom use among adolescents.

The effect of spin-orbit coupling on molecular properties: Potential energy curve, transition dipole moment and laser cooling scheme of NH.

The influence of spin-orbit coupling on the cooling of NH molecular laser is investigated based on the ab initio theory. The potential energy curves (PECs) and spectral constants for four Λ-S states (X3Σ-, a1Δ, b1Σ+ and A3Π) and eight Ω states [Formula: see text] a1Δ2, [Formula: see text] and [Formula: see text] ) of NH molecule are obtained by the multi-reference configuration interaction (MRCI) plus Davidson correction. The spectroscopic constants (Re, ωe, ωeχe, Be, De) are obtained by solving the one dimensional radial Schrödinger equation, and the results are almost the same as the previously reported data. In addition, the transition dipole moment, permanent dipole moment, Franck-Condon factors, and radiative lifetime of NH molecule are also acquired. Also, the effects of the intermediate state on the [Formula: see text] , [Formula: see text] and [Formula: see text] transitions are considered. The feasible laser cooling schemes using a single laser are formulated. In the proposed cooling scheme, there wavelengths for the [Formula: see text] are used, the main pump lasers are λ00 = 335.74 nm. The feasible transition is based on this. It is found that spin-orbit coupling has a significant effect on potential energy curves, permanent dipole moments, transition dipole moments and vibration energy levels.

Fock-space relativistic coupled cluster study on the RaF molecule promising for the laser cooling.

The potential energy curves of the ground and five low-lying excited terms of the RaF molecule are calculated using the Fock-space relativistic coupled theory. The electronic term energies, equilibrium internuclear distances, transition and permanent dipole moments, sequences of vibrational energies, harmonic vibrational frequencies, Franck-Condon factors, and radiative lifetimes are predicted. The calculated spectroscopic constants are in good agreement with the available theoretical and experimental data. The scheme for the direct laser cooling involving the first excited A2П1/2 state is proposed. The data obtained in this study suggests the A2П1/2 â†’ X2Σ+ channel in the RaF molecule is the almost ideal case for direct laser cooling. It is quite possible that the effective cooling scheme for the RaF molecule can be realized using only one pump laser.