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1.
Horm Behav ; 161: 105522, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38447330

RESUMEN

Testosterone plays an important role as a social hormone. Current evidence suggests that testosterone is positively related to sociosexuality increasing the psychological attitudes toward investing in short-term versus long-term mating and promotes status-seeking behaviors both by dominance and prestige. In addition, the social environment may play an important role in the expression of mating effort through changes in sociosexuality and status-seeking behaviors. However, the causal relationships among the mentioned variables are still debated. We employed a double-blind, placebo-controlled within-individual design, in order to test and integrate the proposed causal relationships between testosterone and social environment over short-term and long-term mating orientation and dominant and prestigious status-seeking behaviors in a sample of 95 young Chilean men. We did not find evidence that the administration of exogenous testosterone increased short-term or decreased long-term mating orientation as expected. Moreover, exogenous testosterone did not affect either aggressive or cooperative behavior failing to support the social status hypothesis. We also did not find any relationship between short or long-term mating orientation with status-seeking behaviors. Finally, we found support for the effect of social environment on sociosexual attitudes but not over status-seeking behaviors. Thus, men reported higher levels of short-term mating orientation in the presence of a woman compared to a man and no differences were found for long-term mating orientation. We argue that sociosexuality may be expressed flexibly, but contextual factors such as the presence of women seem more important than changes in testosterone levels.


Asunto(s)
Medio Social , Testosterona , Masculino , Humanos , Chile , Método Doble Ciego , Adulto Joven , Adulto , Conducta Sexual/fisiología , Conducta Sexual/psicología , Conducta Social , Adolescente , Femenino , Predominio Social
2.
Sci Rep ; 13(1): 17742, 2023 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-37853104

RESUMEN

Intergroup conflict has been a persistent aspect of human societies since the emergence of our species. Various researchers have proposed that competition between groups has acted as a key selective force throughout human evolutionary history. Such intergroup competition for limited resources exacerbated the expression of intergroup aggression and intragroup cooperation. Furthermore, it would have a sexual dimorphism, with men demonstrating increased sensitivity to conflict threats-in order to maximize reproductive opportunities-, while women generally reject from active engagement in intergroup conflict. In the present study, we conducted behavioral experiments under controlled laboratory conditions to measure cooperation and aggression from using virtual games, specifically the Public Good Games and the Point Subtraction Aggression Paradigm, in a sample of 541 participants. We created control and experimental intergroup competition scenarios, where aggression and cooperation were necessary to increase monetary rewards. Our results shows that men modulate aggression and cooperation in the presence of intergroup conflict. In addition, our data also reveals that women cooperate more than men and display heightened levels of cooperation and aggression when confronted with intergroup conflict. These findings prompt a reevaluation of current functional theoretical models concerning the role of women in intergroup conflict and suggest that the dynamics of human aggression and cooperation may be more nuanced than previously believed.


Asunto(s)
Agresión , Evolución Biológica , Masculino , Humanos , Femenino , Modelos Teóricos
3.
Nurs Rep ; 13(3): 1138-1147, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37606466

RESUMEN

Background: The COVID-19 pandemic made nurse-patient-family communication more difficult, reducing the understanding of the patient's wishes and current care history. COVID-19 challenged healthcare teams to develop strategies to address these changes and provide more integrated care using the technology at their disposal. So, this study aims to map the strategies used by nurses to maintain communication between the person hospitalized with COVID-19 and the family to understand which communication technologies were most used to maintain communication between the person and the family. Methods: A Scoping Review, according to the recommendations of the Joanna Briggs Institute [JBI] with the Preferred Reporting Items for Scoping Review extension (PRISMA-ScR), research conducted between September 2022 and January 2023. The search was conducted in the databases: Latin American and Caribbean Literature in Health Sciences (LILACS); Cumulative Index of Nursing and Allied Health Literature (CINAHL); Scientific Electronic Library Online (SciELO); Medical Literature Analysis and Retrieval System Online (Medline), using the descriptors: family, communication, nurses, hospitals and COVID-19, and the Boolean operators "AND". The inclusion criteria were: original articles, in Portuguese, English, and Spanish, published from 2020 onwards, with access to full and free text. Results: It was found that most of the communication was unstructured with the family. The technologies most used by nurses were the telephone with video calls from the patients themselves and even from health professionals to maintain communication between the patient and the family. Conclusions: Communication between patients and families became essential during the pandemic, as it became a vital lifeline of human connection that supported the mental health of patients and their families. This study was not registered.

4.
Behav Processes ; : 104627, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35364224

RESUMEN

Dominance hierarchies vary between species and possess particular characteristics depending on the distribution and abundance of food resources that affect the competitive regime. Bonobos have been described as having female intersexual dominance, based mainly on female coalitionary support against males, and more egalitarian hierarchies than chimpanzees. In this study, we tested whether female intersexual dominance is dependent on female coalitions or whether it still arises when only dyadic interactions are considered. We also examined the role of food abundance in shaping dominance style in a wild population of bonobos in Wamba, Democratic Republic of Congo. We found partial support concerning our first prediction in which we expected a male dominance over females when only dyadic agonistic interactions were considered because females were not systematically dominant over males, finding instead an intersexual codominance pattern. We failed to find support for our second prediction that hierarchies become more despotic under low fruit abundance, in fact, we found the opposite pattern. We discuss that codominance based on dyadic interactions in this group may arise as a consequence of male deference rather than females winning conflicts against males and that more despotic hierarchies during high fruit season may arise as a consequence of competition for high-quality resources or variation in party size.

5.
Front Psychol ; 13: 815819, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35282237

RESUMEN

From an evolutionary perspective, phenotypic, social, and environmental factors help to shape the different costs and benefits of pursuing different reproductive strategies (or a mixture of them) from one individual to another. Since men's reproductive success is mainly constrained to women's availability, their mating orientations should be partially calibrated by features that women prefer in a potential partner. For long-term relationships, women prefer traits that signal access to resources, protection skills, and the willingness to share them. Using generalized linear models with laboratory data taken from a Chilean population (N = 197), this study aimed to test whether real and potential resources (measured as self-reported socioeconomic status), protection skills (measured as handgrip strength), and the willingness to provide resources and protection (measured as their disposition toward parenthood) are related to mating orientation in men. Our predictions were: (1) socioeconomic status would be positively associated with long-term and short-term mating orientation but for long-term-oriented individuals, this would be enhanced by having a more favorable parenthood disposition and (2) strength would be positively related to long-term mating orientation in men with higher socioeconomic status and a favorable disposition toward parenthood and it would have a positive and direct association with short-term mating orientation. Our results partially supported the first hypothesis, since men with higher socioeconomic status were more long-term oriented, but parenting disposition did not moderate this effect. Contrary to our expectations, socioeconomic status was not related to short-term mating orientation. Strength appeared not to be significant for long-term mating orientation, even interacting with other traits. However, strength by itself was powerfully linked with a short-term mating orientation. Our results suggest that only some individuals that are attractive for long-term relationships are indeed long-term oriented and may reflect the overall conflict of interests between mating strategies among sexes.

6.
Behav Sci (Basel) ; 12(2)2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35200293

RESUMEN

In both sexes, aggression has been described as a critical trait to acquire social status. Still, almost uniquely in men, the link between aggressiveness and the genetic background of testosterone sensitivity measured from the polymorphism in the androgen receptor (AR) gene has been previously investigated. We assessed the relevance of the AR gene to understand aggression and how aggressiveness affects social status in a cross-sectional study of 195 participants, for the first time in both young men and women. We estimated polymorphism sequences from saliva and measured aggression and self-perceived social status. Unfortunately, the results did not support our prediction because we did not find any of the expected relationships. Therefore, the results suggest that the genetic association between aggressive mechanisms and polymorphism of the AR gene is less straightforward than expected, at least in men, and seems to indicate that aggression is not usually used to gain social status in our population.

8.
Sensors (Basel) ; 21(4)2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33672255

RESUMEN

This paper presents a framework for processing, modeling, and fusing underwater sensor signals to provide a reliable perception for underwater localization in structured environments. Submerged sensory information is often affected by diverse sources of uncertainty that can deteriorate the positioning and tracking. By adopting uncertain modeling and multi-sensor fusion techniques, the framework can maintain a coherent representation of the environment, filtering outliers, inconsistencies in sequential observations, and useless information for positioning purposes. We evaluate the framework using cameras and range sensors for modeling uncertain features that represent the environment around the vehicle. We locate the underwater vehicle using a Sequential Monte Carlo (SMC) method initialized from the GPS location obtained on the surface. The experimental results show that the framework provides a reliable environment representation during the underwater navigation to the localization system in real-world scenarios. Besides, they evaluate the improvement of localization compared to the position estimation using reliable dead-reckoning systems.

9.
Methods Mol Biol ; 2216: 591-610, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33476026

RESUMEN

Renal hypoxia is generally accepted as a key pathophysiologic event in acute kidney injury of various origins and has also been suggested to play a role in the development of chronic kidney disease. Here we describe step-by-step data analysis protocols for MRI monitoring of renal oxygenation in rodents via the deoxyhemoglobin concentration sensitive MR parameters T2* and T2-a contrast mechanism known as the blood oxygenation level dependent (BOLD) effect.This chapter describes how to use the analysis tools provided by vendors of animal and clinical MR systems, as well as how to develop an analysis software. Aspects covered are: data quality checks, data exclusion, model fitting, fitting algorithm, starting values, effects of multiecho imaging, and result validation.This chapter is based upon work from the PARENCHIMA COST Action, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This experimental protocol chapter is complemented by two separate chapters describing the basic concept and data analysis.


Asunto(s)
Biomarcadores/análisis , Medios de Contraste/química , Procesamiento de Imagen Asistido por Computador/métodos , Riñón/fisiología , Imagen por Resonancia Magnética/métodos , Monitoreo Fisiológico/métodos , Oxígeno/sangre , Algoritmos , Animales , Consumo de Oxígeno , Programas Informáticos
10.
PLoS One ; 15(8): e0237315, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32866153

RESUMEN

The decision to allocate time and energy to find multiple sexual partners or raise children is a fundamental reproductive trade-off. The Strategic Pluralism Hypothesis argues that human reproductive strategies are facultatively calibrated towards either investing in mating or parenting (or a mixture), according to the expression of features dependent on the individual's condition. This study seeks to test predictions derived from this hypothesis in a sample of 242 young men (M ± SD = 22.12 ± 3.08) from Chile's 5th Region (33Ö¯ south latitude). Specifically, two predictions were considered that raise questions about the relationship between traits related to physical and psychological attractiveness (fluctuating facial asymmetry and self-perception of attractiveness) and competitive skills (baseline testosterone and self-perception of fighting ability) with short-term reproductive strategies. Our results indicate that psychological features related to the self-perception of physical attractiveness are related to short-term reproductive strategies. However, no evidence was found that fluctuating facial asymmetry, basal levels of testosterone and self-perception of fighting ability were related to short-term reproductive strategies. These results support the existing evidence of the importance of physical attractiveness in calibrating men's reproductive strategies but cast doubts about the role of fluctuating facial asymmetry. They also suggest that traits related to physical attractiveness, in comparison to competitive capabilities, play a more important role in calibrating men's short-term reproductive strategies.


Asunto(s)
Belleza , Conducta de Elección , Reproducción/fisiología , Autoimagen , Conducta Sexual/psicología , Adolescente , Adulto , Chile , Conducta Competitiva/fisiología , Humanos , Parejas Sexuales/psicología , Encuestas y Cuestionarios/estadística & datos numéricos , Testosterona/sangre , Testosterona/fisiología , Adulto Joven
11.
Phys Med ; 71: 71-81, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32092688

RESUMEN

PURPOSE: To develop a phantom for methodological radiomic investigation on Magnetic Resonance (MR) images of female patients affected by pelvic cancer. METHODS: A pelvis-shaped container was filled with a MnCl2 solution reproducing the relaxation times (T1, T2) of muscle surrounding pelvic malignancies. Inserts simulating multi-textured lesions were embedded in the phantom. The relaxation times of muscle and tumour were measured on an MR scanner on healthy volunteers and patients; T1 and T2 of MnCl2 solutions were evaluated with a relaxometer to find the concentrations providing a match to in vivo relaxation times. Radiomic features were extracted from the phantom inserts and the patients' lesions. Their repeatability was assessed by multiple measurements. RESULTS: Muscle T1 and T2 were 1128 (806-1378) and 51 (40-65) ms, respectively. The phantom reproduced in vivo values within 13% (T1) and 12% (T2). T1 and T2 of tumour tissue were 1637 (1396-2121) and 94 (79-101) ms, respectively. The phantom insert best mimicking the tumour agreed within 7% (T1) and 24% (T2) with in vivo values. Out of 1034 features, 75% (95%) had interclass correlation coefficient greater than 0.9 on T1 (T2)-weighted images, reducing to 33% (25%) if the phantom was repositioned. The most repeatable features on phantom showed values in agreement with the features extracted from patients' lesions. CONCLUSIONS: We developed an MR phantom with inserts mimicking both relaxation times and texture of pelvic tumours. As exemplified with repeatability assessment, such phantom is useful to investigate features robustness and optimise the radiomic workflow on pelvic MR images.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Músculos/diagnóstico por imagen , Neoplasias Pélvicas/diagnóstico por imagen , Neoplasias Pélvicas/radioterapia , Pelvis/diagnóstico por imagen , Radiometría , Adulto , Cloruros/química , Femenino , Voluntarios Sanos , Humanos , Compuestos de Manganeso/química , Persona de Mediana Edad , Fantasmas de Imagen , Reproducibilidad de los Resultados , Adulto Joven
12.
Evol Psychol ; 17(2): 1474704919852918, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31167552

RESUMEN

Bodily attractiveness is an important component of mate value. Musculature-a crucial component of men's bodily attractiveness-provides women with probabilistic information regarding a potential mate's quality. Overall musculature is comprised of several muscle groups, each of which varies in information value; different muscles should be weighted differently by attractiveness-assessment adaptations as a result. In the current study, women and men ( N = 1,742) reported size preferences for 14 major muscle groups. Women's reported preferences provided only partial support for our hypotheses that women will prefer muscles that most reliably differentiate between potential mates to be larger; men tended to prefer larger upper-body muscles. We discuss possible interpretations of these mixed findings. Ultimately, our findings suggest that attractiveness-assessment adaptations are sensitive to the information contained within specific muscle groups and they highlight the potential for additional research on the nuances of bodily attractiveness assessment.


Asunto(s)
Belleza , Composición Corporal/fisiología , Hombres , Músculo Esquelético , Aptitud Física/psicología , Parejas Sexuales , Adolescente , Adulto , Conducta de Elección/fisiología , Femenino , Humanos , Masculino , Adulto Joven
13.
J Magn Reson Imaging ; 50(5): 1583-1592, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30990938

RESUMEN

BACKGROUND: The high acoustic impedance of the skull limits the performance of transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) therapy. Subject suitability screening is based on skull parameters estimated from computed tomography (CT) scans. PURPOSE: To assess the feasibility of screening for tcMRgFUS based on zero echo time (ZTE) MRI, and to explore the influence of measurable skull parameters in treatment performance. STUDY TYPE: Retrospective. POPULATION: Sixteen patients treated with tcMRgFUS thalamotomy for tremor. SEQUENCE: ZTE on a 3.0T GE scanner. ASSESSMENT: Baseline CT and ZTE images were processed to extract skull measures associated with treatment success: skull density ratio (SDR), skull thickness, and angle of incidence. Eight new metrics were proposed. CT and ZTE-based measures were compared. Each subject's energy-temperature curve was processed to extract a global estimate of efficiency and a measure of nonlinearity. These parameters were then correlated with the skull measures. STATISTICAL TESTS: Linear regression analysis to compare ZTE vs. CT-based measures, measures vs. efficiency, and measures vs. nonlinearity. Paired t-test to assess nonlinearity. RESULTS: CT and ZTE-based measures were significantly correlated (P < 0.01). In particular, classical metrics were robustly replicated (P < 0.001). The energy-temperature curves showed a nonlinear (logarithmic) relationship (P < 0.01). This nonlinearity was greater for thicker skulls (P < 0.01). Efficiency was correlated with skull thickness (P < 0.001) and SDR (P < 0.05). DATA CONCLUSION: The feasibility of ZTE-based screening has been proven, potentially making it possible to avoid ionizing radiation and the extra imaging session required for CT. The characterization of the influence that skull properties have on tcMRgFUS may serve to develop patient-specific heating models, potentially improving control over the treatment outcome. The relationship of skull thickness with efficiency and nonlinearity empowers the role of this metric in the definition of such models. In addition, the lower association of SDR with the energy-temperature curves emphasizes the need of revisiting this metric. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1583-1592.


Asunto(s)
Imagen por Resonancia Magnética , Cráneo/diagnóstico por imagen , Temblor/terapia , Terapia por Ultrasonido , Acústica , Anciano , Estudios de Factibilidad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Lineales , Masculino , Persona de Mediana Edad , Dinámicas no Lineales , Temperatura , Tálamo/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Temblor/diagnóstico por imagen
14.
Am J Hum Biol ; 31(3): e23235, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30884051

RESUMEN

OBJECTIVES: Strategic Pluralism Theory contends that human mating strategies are calibrated toward short-term (ST) or long-term (LT) mating according to the expression of condition-dependent traits and characteristics of the social and physical environment. Traits reflecting the effects of testosterone have been considered condition-dependent traits that provide information about the calibration of male mating strategy. We investigated the relationship of muscle mass and facial masculinity with attitudes and behaviors reflecting ST and LT mating tactics. METHODS: We measured skeletal muscle mass (SMM) through bioelectrical impedance and facial width-to-height ratio (fWHR) in a sample of Chilean men (n = 206; mean age = 22.52 ± 4.65 SD), and collected information about sociosexual attitudes and past sexual behavior. RESULTS: Our results showed an interaction effect of SMM and fWHR on unrestricted (but not restricted) sociosexual attitudes and past sexual behavior. Individuals with a consistent expression of both traits (ie, high SMM and fWHR or low SMM and fWHR) reported higher levels of unrestricted sociosexual attitudes and a greater number of lifetime and previous-year sexual partners. CONCLUSIONS: These findings suggest that the intensity and consistency of expression of body and facial masculinity is important in signaling male mating tactics and sociosexual attitudes.


Asunto(s)
Actitud , Cara/anatomía & histología , Masculinidad , Músculo Esquelético/fisiología , Conducta Sexual/psicología , Testosterona/metabolismo , Adolescente , Adulto , Chile , Humanos , Masculino , Adulto Joven
15.
Front Psychol ; 10: 18, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30723439

RESUMEN

Objective: There is evidence that competitive conflicts are the main form of intrasexual competition among men. The capacity to recognize visual cues of fighting ability in competitors is thought to be an important characteristic that allows men to avoid the costs of contest competition. However, for an accurate comparison to take place, individuals need to compare the fighting ability of their competitors to their own to assess this asymmetry. Methods: In order to improve our understanding of this self-assessment process, here we study the relationship between visual fighting ability cues, namely (i) muscularity, as measured with a bioimpedance device, (ii) the real capacity to inflict cost to a rival based on strength, as measured with a hand grip dynamometer (HGS), and (iii) self-perceived fighting ability, as determined with a questionnaire. The study sample was 364 men between 18 and 38 years of age (M ± SD = 22.27 ± 3.99). Results: Our results confirm the expected positive relationship between upper-body muscularity and strength, while controlling for body mass index (BMI). However, muscularity explained only around 30.2% of the variance in strength. In addition, muscularity was related to self-perception of fighting ability in our sample, its effect being partially mediated by strength. Conclusion: The more muscular men perceive their fighting ability as being greater, and not only because they are stronger (at least in the HGS task). Accordingly, it seems that men take into account the overestimation the robustness of the relationship between strength and muscularity that prevails within his peers.

16.
Sensors (Basel) ; 19(1)2019 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-30609863

RESUMEN

The problem of attitude estimation is broadly addressed using the Kalman filter formalism and unit quaternions to represent attitudes. This paper is also included in this framework, but introduces a new viewpoint from which the notions of "multiplicative update" and "covariance correction step" are conceived in a natural way. Concepts from manifold theory are used to define the moments of a distribution in a manifold. In particular, the mean and the covariance matrix of a distribution of unit quaternions are defined. Non-linear versions of the Kalman filter are developed applying these definitions. A simulation is designed to test the accuracy of the developed algorithms. The results of the simulation are analyzed and the best attitude estimator is selected according to the adopted performance metric.


Asunto(s)
Orientación Espacial , Reconocimiento de Normas Patrones Automatizadas/métodos , Procesamiento de Señales Asistido por Computador , Algoritmos , Fenómenos Biomecánicos , Simulación por Computador , Modelos Estadísticos
17.
Interdisciplinaria ; 34(2): 351-368, dic. 2017. ilus, tab
Artículo en Español | LILACS | ID: biblio-975778

RESUMEN

Durante los últimos años en Chile se ha detectado una masificación en el uso de anticonceptivos orales. Sin embargo, en Chile y al igual que en casi todos los países latinoamericanos prácticamente no se han investigado sus implicancias sobre la conducta humana. Específicamente, este estudio evaluó el impacto del uso de estos anticonceptivos sobre la conducta de emparejamiento en un grupo de 164 mujeres jóvenes universitarias, con una media de edad igual a 19 años y provenientes de cuatro universidades chilenas. Para ello se utilizó la adaptación chilena del Cuestionario de Componentes del Valor de Pareja que está compuesto por 22 ítems que se responden en una escala Likert de siete valores. Los resultados señalan diferencias entre las mujeres que consumen píldoras anticonceptivas (PA) y las que no lo hacen. Las consumidoras presentan los mayores valores del índice general del cuestionario sobre los componentes del valor de pareja y las subescalas de historia de relaciones de pareja, apreciación desde el sexo opuesto y apariencia. Estos resultados indican que las mujeres consumidoras de la PA se autoperciben y creen que el sexo contrario las evalúa como atractivas y muestran una vida sexual más diversificada, no mostrando diferencias en los otros aspectos relevantes para el valor de pareja no vinculados centralmente al atractivo físico. En definitiva, los resultados parecen indicar que el consumo de anticonceptivos hormonales no modifica la conducta social y parental de las mujeres, aunque su uso parece estar asociado con una mayor autopercepción de atractivo y mayor diversidad sexual.


Oral contraceptives, also known as birth control pills (PAs from now on), have been available on the world market for five decades. At present, the use of PA is massifier worldwide, being consumed by more than 100 million women on the planet. In recent years, in Latin America has been detected a dramatic increase in the use of oral contraceptives, and Chile is not the exception. In this sense, it is probable that the increase in the consumption of PAs in Chile is linked to the increase of women who decide to pursue higher studies and to develop professional careers. Concurrently, a wide field of research has been focused on the physiological and psychological effect of the consumption of oral contraceptives on human behavior, being mating behavior one of the main topics of research. However, in Chile as in most Latin American countries there is a lack of studies on the implications of the consumption of oral contraceptives on human behavior. In the present study, we investigated in a group of 164 university young women (Mean ± Standard Deviation: 19.27± 2.88 years) of Chile the impact of the use of oral contraceptives on mating behavior. Accordingly, we have applied a validated psychometric test to assessed mate value, one of the more relevant components of mating behavior i.e., the Mate Value Questionnaire. Mate value can be defined as a construct that incorporates a number of physical, psychological, and social dimensions that are related to an individual's ability to find, attract, and successfully retain a partner. This questionnaire is composed by 22 items and 7 subscales that are answered in a Likert Scale of 7 values. The Mate Value Questionnaire showed a high reliability (α = .85). According with previous studies that showed a decrease in sexual satisfaction and desire on women that consume oral contraceptives, we predicted a decrease of mating behavior and, then, a decrease on Mate Value for those women that use oral contraceptives. This effect was expected for all subscales of this questionnaire with the exception of relationship history subscale since women that consume oral contraceptives reported to have more diverse sexual partners on previous studies. The results show differences between women who use oral contraceptives (n = 87 women: 19.60 ± 2.89 years) in comparison to those who do not (n = women: 18.90 ± 2.84 years). However, the differences were, in general, opposed to our expectations being the consumers of oral contraceptives who presented the highest values of the general index of the Mate Value Questionnaire, and, concretely, for the subscales of relationship history, views of the opposite sex, and looks. In addition, we have failed into found any differences between groups in subscales that were not associated to physical appearance, such as wealth, sociality and fear of failure. The results suggest that the use of hormonal contraceptives does not modify the social and parental behavior of the women, although their use seems to be associated with a greater self-perception of attractiveness and greater diversity in sexual life. This study provides new information that will increase the understanding and discussion about the hypothetical effect that would or would not, the consumption of the PA on the pairing behavior. It is important to point out that the field of research on changes in the sexual preferences of women, derived from hormonal states, is in an important discussion process. Therefore, we believe that it is critical to carry out research in the future in order to elucidate the real robustness of this phenomenon, improving our understanding about the behavioral effects of consuming oral contraceptives.

18.
Am J Primatol ; 78(11): 1149-1164, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27273743

RESUMEN

In environments where energy demands and resource availability vary seasonally, individuals are expected to time the optimal allocation of resources to support survival and reproduction. Although female baboons are regarded as all year round, capital breeders, we wondered how they would respond in an ecological scenario where food were not limiting, foraging effort were negligible, and they were thermally stressed during the cold winter. This study analyzes a 30-year database of conceptions, births, resumptions of postlactational ovarian activity, menarches, and prenatal and early postnatal reproductive failures recorded in a food-provisioned colony of hamadryas baboons located in a temperate zone (40°25'N) to search for seasonal patterns in their life-history patterns and explore its fitness consequences. The results show that the study females exhibited moderate seasonality and behaved like capital breeders; ovarian activity peaked during the period of benign weather conditions (spring and early summer) and births and lactation peaked during the period when they were thermally stressed and faced a negative energy balance (winter). Mistimed conceptions were more likely to fail than timed conceptions were, although this association could be artefactual due to the difficulty to accurately detect prenatal losses. Insolation and, to a lesser extent, temperature were positively associated with conceptions, resumptions of postlactational ovarian activity and onsets of menarche, and negatively associated with births. These findings highlight the extent of plasticity (width of peaks) and resiliency (retention of a capital breeding tactic even under highly seasonally thermally stressful cold conditions) in how primates can adjust their life history patterns and solve tradeoffs in a scenario of strong seasonal variation. Am. J. Primatol. 78:1149-1164, 2016. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Papio hamadryas , Preñez/fisiología , Reproducción , Animales , Femenino , Lactancia , Embarazo , Estaciones del Año , Temperatura
19.
Magn Reson Imaging ; 34(3): 334-44, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26612079

RESUMEN

The method of Arterial Spin Labeling (ASL) has experienced a significant rise in its application to functional imaging, since it is the only technique capable of measuring blood perfusion in a truly non-invasive manner. Currently, there are no commercial packages for processing ASL data and there is no recognized standard for normalizing ASL data to a common frame of reference. This work describes a new Automated Software for ASL Processing (ASAP) that can automatically process several ASL datasets. ASAP includes functions for all stages of image pre-processing: quantification, skull-stripping, co-registration, partial volume correction and normalization. To assess the applicability and validity of the toolbox, this work shows its application in the study of hypoperfusion in a sample of healthy subjects at risk of progressing to Alzheimer's disease. ASAP requires limited user intervention, minimizing the possibility of random and systematic errors, and produces cerebral blood flow maps that are ready for statistical group analysis. The software is easy to operate and results in excellent quality of spatial normalization. The results found in this evaluation study are consistent with previous studies that find decreased perfusion in Alzheimer's patients in similar regions and demonstrate the applicability of ASAP.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Reconocimiento de Normas Patrones Automatizadas/métodos , Marcadores de Spin , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/fisiopatología , Automatización , Encéfalo/patología , Mapeo Encefálico/métodos , Circulación Cerebrovascular , Gráficos por Computador , Femenino , Voluntarios Sanos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional , Internet , Masculino , Distribución Normal , Perfusión , Probabilidad , Reproducibilidad de los Resultados , Programas Informáticos
20.
PLoS One ; 9(3): e90996, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24621865

RESUMEN

During male takeovers, in addition to fighting off the female's current mating partner, males may exhibit intense aggressive mate guarding of the newly acquired females. Recent studies indicate that coercive sexual aggression by males is an important strategy through which sexual conflict is expressed. Previous tests of the sexual coercion hypothesis in primates have focused on assessing if female mate choice is effectively reduced by male aggression, however, only one recent study has tested a critical prediction of this hypothesis, namely, that male coercion is reproductively costly to victim females. The present study uses 15 years of data on inter-birth intervals from a large multilevel colony of baboons, mostly Papio h. hamadryas, with a mating system based on harem-defence polygyny to examine if male takeovers impact the length of the abducted females' inter-birth intervals. Our analysis of 121 inter-birth intervals from 45 adult females indicates that male takeovers are reproductively costly to abducted females as they are associated with an increase in the time they take to conceive and a lengthening of the inter-birth intervals. We discuss how several factors may contribute to this reproductive cost, including male-female sexual conflict, male-male competition, and female-female competition. Our findings suggest that the male's aggressive herding is the main contributor to the abducted females' immediate reproductive cost. We argue that although some of the male's aggressive herding may be driven by male-male competition, nonetheless, it serves a coercive function as it both constrains the female's mate choice options and hampers her immediate breeding performance. This conclusion is backed up by results obtained in the only other study that has tested the same prediction and which has been carried out in a wild population of hamadryas baboons.


Asunto(s)
Coerción , Papio hamadryas/fisiología , Reproducción , Conducta Sexual Animal , Animales , Cruzamiento , Conflicto Psicológico , Femenino , Fertilización , Masculino , Factores de Tiempo
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