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2.
J Chem Phys ; 148(24): 244302, 2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29960347

RESUMO

Photoabsorption cross sections and oscillator strengths for the strong, predissociating vibrational bands, v ≥ 11, in the S2 BΣu-3-XΣg-3(v,0) system are reported. Absorption measurements were undertaken on S2 vapor produced by a radio-frequency discharge through H2S seeded in helium, and also in a two-temperature sulfur furnace, at temperatures of 370 K and 823 K, respectively. S2 column densities were determined in each source by combining experimental line strengths in low-v non-predissociating B - X bands (v < 7) with calculated line f-values based on measured radiative lifetimes and calculated branching ratios. The broad-band capabilities of two vacuum-ultraviolet Fourier-transform spectrometers, used with instrumental resolutions of 0.22 cm-1 and 0.12 cm-1, respectively, allowed for simultaneous recordings of both non-predissociating and predissociating bands, thus placing the predissociating-band cross sections on a common absolute scale. Uncertainties in the final cross section datasets are estimated to be 15% for the 370-K vapor and 10% for the 823-K vapor. The experimental cross sections are used to inform a detailed predissociation model of the B(v) levels in Paper II [Lewis et al., J. Chem. Phys. 148, 244303 (2018)]. For astrophysical and other applications, this model can be adjusted simply to provide isotopologue-specific cross sections for a range of relevant temperatures.

3.
Nat Commun ; 9(1): 2433, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29970895

RESUMO

In modern human cultures where social hierarchies are ubiquitous, people typically signal their hierarchical position through consumption of positional goods-goods that convey one's social position, such as luxury products. Building on animal research and early correlational human studies linking the sex steroid hormone testosterone with hierarchical social interactions, we investigate the influence of testosterone on men's preferences for positional goods. Using a placebo-controlled experiment (N = 243) to measure individuals' desire for status brands and products, we find that administering testosterone increases men's preference for status brands, compared to brands of similar perceived quality but lower perceived status. Furthermore, testosterone increases positive attitudes toward positional goods when they are described as status-enhancing, but not when they are described as power-enhancing or high in quality. Our results provide novel causal evidence for the biological roots of men's preferences for status, bridging decades of animal behavioral studies with contemporary consumer research.


Assuntos
Comportamento do Consumidor , Hierarquia Social , Masculinidade , Classe Social , Testosterona/fisiologia , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Astrophys J ; 2382018.
Artigo em Inglês | MEDLINE | ID: mdl-30983596

RESUMO

New branching fraction (BF) measurements based primarily on data from a cross-dispersed echelle spectrometer are reported for 84 lines of Co ii. The BFs for 82 lines are converted to absolute atomic transition probabilities using radiative lifetimes from laser-induced fluorescence (LIF) measurements on 19 upper levels of the lines. A lifetime of 3.3(2) ns for the z5D0 level is used based on LIF measurements for lifetimes of the four other levels in the z5D term. Twelve of the eighty-four lines are weak transitions connecting to the ground and low metastable levels of Co+. Another 46 lines are strong transitions connecting to the ground and low metastable levels of Co+. For these lines, log(gf) values were measured in earlier studies and, with a few exceptions, are confirmed in this study. Such lines, if unblended in stellar spectra, have the potential to yield Co abundance values unaffected by any breakdown of the local thermodynamic equilibrium approximation in stellar photospheres because the ground and low metastable levels of Co+ are the primary population reservoirs of Co in the photospheres of interest. Weak lines, if unblended, are useful in photospheres with high Co abundance, and strong lines are useful in metal-poor photospheres. New hyperfine structure A constants for 28 levels of ionized Co from least-squares fits to Fourier transform spectra line profiles are reported. These laboratory data are applied to re-determine the Co abundance in the metal-poor halo star HD 84937. BFs and transition probabilities for 19 lines are reported for the first time.

6.
Proc Natl Acad Sci U S A ; 114(48): 12714-12719, 2017 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-29133409

RESUMO

People are exposed to persuasive communication across many different contexts: Governments, companies, and political parties use persuasive appeals to encourage people to eat healthier, purchase a particular product, or vote for a specific candidate. Laboratory studies show that such persuasive appeals are more effective in influencing behavior when they are tailored to individuals' unique psychological characteristics. However, the investigation of large-scale psychological persuasion in the real world has been hindered by the questionnaire-based nature of psychological assessment. Recent research, however, shows that people's psychological characteristics can be accurately predicted from their digital footprints, such as their Facebook Likes or Tweets. Capitalizing on this form of psychological assessment from digital footprints, we test the effects of psychological persuasion on people's actual behavior in an ecologically valid setting. In three field experiments that reached over 3.5 million individuals with psychologically tailored advertising, we find that matching the content of persuasive appeals to individuals' psychological characteristics significantly altered their behavior as measured by clicks and purchases. Persuasive appeals that were matched to people's extraversion or openness-to-experience level resulted in up to 40% more clicks and up to 50% more purchases than their mismatching or unpersonalized counterparts. Our findings suggest that the application of psychological targeting makes it possible to influence the behavior of large groups of people by tailoring persuasive appeals to the psychological needs of the target audiences. We discuss both the potential benefits of this method for helping individuals make better decisions and the potential pitfalls related to manipulation and privacy.


Assuntos
Controle Comportamental/psicologia , Publicidade Direta ao Consumidor/métodos , Comportamento de Massa , Comunicação Persuasiva , Psicometria/métodos , Extroversão Psicológica , Humanos , Individualidade , Introversão Psicológica , Mídias Sociais/estatística & dados numéricos
7.
Astrophys J Suppl Ser ; 228(1)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28579650

RESUMO

New emission branching fraction (BF) measurements for 183 lines of the second spectrum of chromium (Cr II) and new radiative lifetime measurements from laser-induced fluorescence for 8 levels of Cr+ are reported. The goals of this study are to improve transition probability measurements in Cr II and reconcile solar and stellar Cr abundance values based on Cr I and Cr II lines. Eighteen spectra from three Fourier Transform Spectrometers supplemented with ultraviolet spectra from a high-resolution echelle spectrometer are used in the BF measurements. Radiative lifetimes from this study and earlier publications are used to convert the BFs into absolute transition probabilities. These new laboratory data are applied to determine the Cr abundance log ε in the Sun and metal-poor star HD 84937. The mean result in the Sun is 〈logε (Cr II)〉 = 5.624±0.009 compared to 〈logε(Cr I)〉 = 5.644 ± 0.006 on a scale with the hydrogen abundance log ε(H) = 12 and with the uncertainty representing only line-to-line scatter. A Saha (ionization balance) test on the photosphere of HD 84937 is also performed, yielding 〈logε(Cr II)〉 = 3.417 ± 0.006 and 〈log ε(Cr I, lower level excitation potential E. P. >30 eV)〉 = 3.3743±30.011 for this dwarf star. We find a correlation of Cr with the iron-peak element Ti, suggesting an associated nucleosynthetic production. Four iron-peak elements (Cr along with Ti, V, and Sc) appear to have a similar (or correlated) production history-other iron-peak elements appear not to be associated with Cr.

8.
J Neuroendocrinol ; 28(4)2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26991328

RESUMO

The neurohormone oxytocin (OT) has been one the most studied peptides in behavioural sciences over the past two decades. Primarily known for its crucial role in labour and lactation, a rapidly growing literature suggests that intranasal OT (IN-OT) may also play a role in the emotional and social lives of humans. However, the lack of a convincing theoretical framework explaining the effects of IN-OT that would also allow the prediction of which moderators exert their effects and when has raised healthy skepticism regarding the robustness of human behavioural IN-OT research. Poor knowledge of the exact pharmacokinetic properties of OT, as well as crucial statistical and methodological issues and the absence of direct replication efforts, may have lead to a publication bias in the IN-OT literature, with many unpublished studies with null results remaining buried in laboratory drawers. Is there a file drawer problem in IN-OT research? If this is the case, it may also be true in our own laboratory. The present study aims to answer this question, document the extent of the problem and discuss its implications for OT research. For eight studies (including 13 dependent variables overall, as assessed through 25 different paradigms) performed in our laboratory between 2009 and 2014 on 453 subjects, the results obtained were too often not those that were expected. Only five publications emerged from our studies and only one of these reported a null finding. After realising that our publication portfolio has become less and less representative of our actual findings and because the nonpublication of our data might contribute to generating a publication bias in IN-OT research, we decided to retrieve these studies from our drawer and encourage other laboratories to do the same.


Assuntos
Pesquisa Comportamental/estatística & dados numéricos , Ocitocina/farmacologia , Viés de Publicação/estatística & dados numéricos , Administração Intranasal , Encéfalo/efeitos dos fármacos , Humanos , Laboratórios , Ocitocina/administração & dosagem
9.
IEEE Trans Biomed Eng ; 40(9): 877-85, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8288278

RESUMO

A new algorithm for ECG signal compression is introduced. The compression system is based on the subautoregression (SAR) model, known also as the long-term prediction (LTP) model. The "periodicity" of the ECG signal is employed in order to further reduce redundancy, thus yielding high compression ratios. The suggested algorithm was evaluated using an in-house database. Very low bit rates on the order of 70 b/s are achieved with a relatively low reconstruction error (percent rms difference-PRD) of less than 10%. The algorithm was compared, using the same database, with the conventional linear prediction (short-term prediction--STP) method, and was found superior at any bit rate. The suggested algorithm can be considered a generalization of the recently published average beat subtraction method.


Assuntos
Eletrocardiografia , Modelos Estatísticos , Processamento de Sinais Assistido por Computador , Algoritmos , Cardiopatias/diagnóstico , Humanos , Modelos Lineares , Periodicidade , Sensibilidade e Especificidade
10.
Acta Diabetol Lat ; 28(1): 47-53, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1862691

RESUMO

The aim of this work was to observe whether different types of carbohydrates might require different insulin doses. Five type 1 CSII-treated diabetic subjects (age 39 +/- 4 years), C-peptide negative and in optimal metabolic control (HbA1c 7.5 +/- 0.2) were selected for the study. They were connected to the Biostator 6 times with an interval of 4-10 days between sessions and fed a meal containing 75 g of carbohydrates of different types: bread, pasta, potatoes, apples, oranges and sucrose. The following net (above basal) insulin requirement for the 30 meals were found (IU - mean + SD): bread 9.15 +/- 1.97; pasta 6.00 +/- 1.37; potatoes 7.05 +/- 2.58; apples 4.54 +/- 1.42; oranges 6.21 +/- 2.62; sucrose 7.83 +/- 2.33. A statistically significant difference was found by ANOVA among insulin requirements for foods (p less than 0.05). Single comparisons between bread and the other foods showed a statistically significant difference only between bread and apple (p less than 0.05). Mean coefficient of variation was 33.9% for the subjects and 30.7% for the meals. A significant correlation was found between Jenkins' glycaemic index and insulin requirement (r = 0.897; p less than 0.001). In conclusion, the high intraindividual variability of insulin requirement does not advice the use of the glycaemic index during optimized insulin therapy.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Dieta para Diabéticos , Carboidratos da Dieta , Adulto , Análise de Variância , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Hemoglobinas Glicadas/análise , Humanos , Sistemas de Infusão de Insulina
12.
Boll Soc Ital Biol Sper ; 61(3): 351-6, 1985 Mar 30.
Artigo em Italiano | MEDLINE | ID: mdl-3896263

RESUMO

Previous studies suggested that insulin requirement in type I diabetics could be split in a "basal" insulin requirement, mainly related to body weight and in a "post-prandial" insulin requirement, mainly related to carbohydrates intake. In the present study we wanted to investigate the occurrence and the magnitude of insulin response to protein only or fat only meals in normal subjects, trying to obtain some evidences for an insulin requirement possibly related to these substrates in diabetic subjects. Fat only meals did not evoke any insulin response while a small but significant increase in plasma insulin was observed after a protein only meal (from 16.6 +/- 2.85 to 25.83 +/- 2.52 microU at 90', p less than 0.05). Blood glucose remained unchanged after fat or protein meals. It is concluded that a small sovrabasal insulin dose would be probably required by diabetic patients after a protein meal: this is however so small that a carbohydrates related insulin dose given before a normal mixed meal would be able to normalize aminoacids as well as glucose metabolism.


Assuntos
Gorduras na Dieta/farmacologia , Proteínas Alimentares/farmacologia , Insulina/metabolismo , Adulto , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Feminino , Humanos , Insulina/sangue , Secreção de Insulina , Masculino , Pessoa de Meia-Idade
13.
Boll Soc Ital Biol Sper ; 60(12): 2267-71, 1984 Dec 30.
Artigo em Italiano | MEDLINE | ID: mdl-6529503

RESUMO

The improvement of glycemic control obtained with weight loss in NIDDM obese diabetics is still lacking of a prediction formula to establish which would be the weight loss to possibly obtain a fasting normoglycemia. Nine NIDDM obese diabetics of both sexes (age 51 +/- 2,64 yrs; initial body weight 91,63 +/- 6,02 Kg., IBW 156,98 +/- 13,38%, fasting plasma IRI 27,58 +/- 6 microU/ml) were hospitalized and discontinued any therapy 10 days before the study. A diet of 600 cal/day was given for a mean period of 20 days. Daily preprandial blood glucose (at 08,00,12,00,19,00 h.) and body weight (on a precision scale) were recorded. Initial fasting blood glucose was 208,89 +/- 16 mg/dl. A mean weight reduction of 3.87 +/- 0.75 Kg was obtained (corresponding to an IBW of only 6,91 +/- 1,35%, being the final IBW of 150,08 +/- 13,59%) which led to a mean blood glucose concentration of 124,89 +/- 7,81 mg/dl. A significant individual linear correlation between weight reductions and mean blood glucose values was found for all subjects with wide differences in the individual slopes of regression lines. In conclusion small weight losses obtained with hypocaloric diets can lead to a nearly normalization of fasting blood glucose, also when the subjects are still well over their ideal body weight.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus/dietoterapia , Dieta Redutora , Obesidade , Adulto , Diabetes Mellitus/sangue , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Appl Res Ment Retard ; 3(2): 141-50, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7125640

RESUMO

A study was conducted on behavioral differences between dependent and independent mildly mentally retarded adolescents and their mothers. Twelve dependent and 12 independent adolescent-mother pairs separately engaged in a videotaped problem solving task. These videotapes were subjected to a behavioral coding system consisting of five domains, i.e., problem solving, positive verbal, negative verbal, positive non-verbal, and negative non-verbal. Differential profiles were not evident between the two groups for either adolescents or their mothers. However, there were notable differences between a more stringently defined subset of dependent and independent adolescents and between their mothers. The subset of independent adolescents were more verbal and active in problem-solving than the dependent adolescents; the dependent subset exhibited a greater rate of negative non-verbal behavior; and mothers of the independent subset presented more positive non-verbal behaviors than did the mothers of the dependent subset.


Assuntos
Dependência Psicológica , Deficiência Intelectual/psicologia , Relações Mãe-Filho , Personalidade , Resolução de Problemas , Adolescente , Feminino , Humanos , Testes Psicológicos , Comportamento Verbal
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