Dominància i ocupació de l'espai en grups de primats no-humans: un model basat en conducta adaptativa

L'estructura jeràrquica és una de les característiques fonamentals de les societats de primats, que condiciona en gran mesura el comportament dels individus que conviuen al grup. Quines lleis regeixen la formació i l'estructura d'aquestes jerarquies? Per què en determinats grups els subjectes més dominants se situen al centre del grup i en uns altres de la mateixa espècie no? En el camp de la conducta animal s'han proposat múltiples hipòtesis, però no n'hi ha cap que siga totalment satisfactòria, ja que a causa de les múltiples variables que hi infl ueixen, és difícil desplegar una teoria que explique tota la complexitat que s'observa empíricament. La nostra proposta d'estudi es basa en l'enfocament de la modelització de la conducta adaptativa, la qual ens permet, mitjançant la simulació informàtica, implementar moltes de les variables que autors com Taste (1995), Koenig (2001) i Barta i Giraldeau (1998) han considerat importants per a l'estructura de formacions jeràrquiques en primats. Seguint el model proposat per Hemelrijk (1998), hem programat un simulador basat en agents, en el qual les regles de conducta implementades fan emergir estructures jeràrquiques complexes. En una primera fase de la investigació, que es desenvolupa en aquest article, hem replicat els estudis de Hemelrijk (1996). Els nostres resultats coincideixen amb els obtinguts per Hemelrijk, cosa que, en posteriors treballs, ens permetrà implementar noves variables al nostre model

Psychological Distress in Erectile Dysfunction : The Moderating Role of Attachment

Introduction: In clinical consultations, men with erectile dysfunction do not always express personal, sexual, and interpersonal concerns. Aim: We explore whether the attenuated impact of erectile dysfunction may be explained by a regulation of negative affect that causes activation of the attachment system. Methods: The study sample consisted of 69 men diagnosed with erectile dysfunction, mean (SD) age 56 (10.83) years. Participants completed self-reported questionnaires to assess erectile dysfunction severity, attachment style, sexual satisfaction, relationship satisfaction, and psychological symptoms. Main Outcome Measure: The moderating role of attachment between erectile dysfunction and sexual satisfaction, relationship satisfaction, and psychological distress was evaluated using multiple linear regression and moderation analysis. Results: All men in the sample had high attachment avoidance, distributed between the dismissive-avoidant (69.6%) and fearful-avoidant (30.4%) substyles, but low levels of psychological symptoms. Despite their erectile dysfunction, 27 patients (39.1%) rated their sexual life as satisfactory, and 46 (66.7%) rated their relationship with their partner as satisfactory. Men with fearful-avoidant attachment reported feeling more sexual desire and less sexual satisfaction than men with dismissive-avoidant attachment. Multiple linear regression analysis showed that sexual satisfaction variance was explained by erectile dysfunction severity, attachment anxiety, and relationship satisfaction scores. Moderation analysis showed that attachment anxiety, but not relationship satisfaction, moderated the impact of erectile dysfunction on sexual satisfaction. Conclusion: The avoidance dimension of attachment, which tends to be high in patients with erectile dysfunction, involves deactivation of the sexual system in an effort to minimize the emotional distress associated with erectile dysfunction, which damages sexual and relationship intimacy and delays the decision to obtain professional help. The presence of high attachment avoidance and the moderating value of attachment anxiety allow us to propose specific treatments for these men. Maestre-Lorén F, Castillo-Garayoa JA, López-i-Martín X, et al. Psychological Distress in Erectile Dysfunction: The Moderating Role of Attachment. Sex Med 2021;9:100436

Further results on why a point process is effective for estimating correlation between brain regions

Signals from brain functional magnetic resonance imaging (fMRI) can be efficiently represented by a sparse spatiotemporal point process, according to a recently introduced heuristic signal processing scheme. This approach has already been validated for relevant conditions, demonstrating that it preserves and compresses a surprisingly large fraction of the signal information. Here we investigated the conditions necessary for such an approach to succeed, as well as the underlying reasons, using real fMRI data and a simulated dataset. The results show that the key lies in the temporal correlation properties of the time series under consideration. It was found that signals with slowly decaying autocorrelations are particularly suitable for this type of compression, where inflection points contain most of the information.Fil: Cifre, I.. Universitat Ramon Llull; EspañaFil: Zarepour Nasir Abadi, Mahdi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Horovitz, S. G.. National Institutes of Health; Estados UnidosFil: Cannas, Sergio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Chialvo, Dante Renato. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentin

Influence of composition and heat treatment on damping and magnetostrictive properties of Fe–18%(Ga + Al) alloys

The structure, magnetostriction and damping properties of Fe82Ga(18−x)Alx (x = 0, 5, 8, 12) alloys were analyzed. The anelastic response of Fe–18(Ga + Al) alloys was studied as a function of temperature (from 0 to 600 °C), frequency (from 0.01 to 200 Hz) and amplitude (from 0.0004% to 0.2%) of forced vibrations. The origin of the relatively high damping capacity of Fe–Ga–Al alloy at room temperature was determined by applying a magnetic field and different heat treatment regimes. The substitution of Ga by Al in Fe–18% Ga alloys was found to decrease magnetostriction and damping. The heat treatment of alloys influences the damping capacity of alloys more than variations of their chemical compositions. Thermally activated frequency and temperature-dependent anelastic effects in Fe–Ga–Al alloys were analyzed and the corresponding activation parameters for relaxation processes were evaluated. Internal friction effects caused by structural transformations were recorded and were found to be consistent with the A2 → D03 → L12 reaction. The physical mechanisms for all anelastic effects are discussed

Polycrystalline silicon films obtained by hot-wire chemical vapour deposition

Silicon films were deposited at moderate substrate temperatures (280-500° C) from pure silane and a silane-hydrogen mixture (10% SiH 4, 90% H 2) in a hotwire CVD reactor. The morphology, structure and composition of the samples were studied with scanning electron microscopy, transmission electron microscopy, transmission electron diffraction, X-ray diffraction, Raman spectroscopy and secondary ion mass spectrometry. The sample deposited at 500° C with pure silane has an amorphous structure, whereas the samples obtained from silane diluted in hydrogen have a polycrystalline structure, even that grown at the lowest temperature (280° C). Polycrystalline samples have a columnar structure with 0.3-1 ?m crystallite sizes with preferential orientation in [220] direction. Deposition rates depend on the filament-substrate distance and range from 9.5 to 37 Å/s for the polycrystalline samples. The high quality of the polycrystalline samples obtained makes the hot-wire technique very promising. Moreover, it is expected to be easily scaled up for applications to large-area optoelectronic devices and to photovoltaic solar cells

One Health Approach to Zoonotic Parasites: Molecular Detection of Intestinal Protozoans in an Urban Population of Norway Rats, Rattus norvegicus, in Barcelona, Spain

Rattus norvegicus, the brown or Norway rat, is the most abundant mammal after humans in urban areas, where they live in close proximity to people. Among rodent-borne diseases, the reservoir role of Norway rats of zoonotic parasites in cities has practically been ignored. Considering the parasitic diseases in the One Health approach, we intended to identify and quantify the zoonotic intestinal protozoans (ZIP) in an urban population of R. norvegicus in the city of Barcelona, Spain. We studied the presence of ZIP in 100 rats trapped in parks (n = 15) as well as in the city's sewage system (n = 85) in the winter of 2016/17. The protozoans were molecularly identified by means of a multiplex PCR (AllplexTM Gastrointestinal Panel-Parasite Assay). We also investigated the presence of co-infections among the species found. Four ZIP were identified, presenting significant prevalences in sewers, specifically Blastocystis (83.5%), Giardia duodenalis (37.7%), Cryptosporidium spp. (34.1%), and Dientamoeba fragilis (14.1%). Several co-infections among the detected ZIP were also detected. The reservoir role of ZIP that Norway rats play in cities as well as the role rats may play as sentinels of zoonotic parasites affecting humans in urban areas are strongly backed up by our findings. The increasing worldwide urbanization, climate change, and the COVID-19 pandemic are factors that are producing an increase in human-rat interactions. Our results should be considered a warning to the authorities to intensify rat control and surveillance in public health interventions

Classification of sleep quality and aging as a function of brain complexity: a multiband non-linear EEG analysis

Understanding and classifying brain states as a function of sleep quality and age has important implications for developing lifestyle-based interventions involving sleep hygiene. Current studies use an algorithm that captures non-linear features of brain complexity to differentiate awake electroencephalography (EEG) states, as a function of age and sleep quality. Fifty-eight participants were assessed using the Pittsburgh Sleep Quality Inventory (PSQI) and awake resting state EEG. Groups were formed based on age and sleep quality (younger adults n = 24, mean age = 24.7 years, SD = 3.43, good sleepers n = 11; older adults n = 34, mean age = 72.87; SD = 4.18, good sleepers n = 9). Ten non-linear features were extracted from multiband EEG analysis to feed several classifiers followed by a leave-one-out cross-validation. Brain state complexity accurately predicted (i) age in good sleepers, with 75% mean accuracy (across all channels) for lower frequencies (alpha, theta, and delta) and 95% accuracy at specific channels (temporal, parietal); and (ii) sleep quality in older groups with moderate accuracy (70 and 72%) across sub-bands with some regions showing greater differences. It also differentiated younger good sleepers from older poor sleepers with 85% mean accuracy across all sub-bands, and 92% at specific channels. Lower accuracy levels (<50%) were achieved in predicting sleep quality in younger adults. The algorithm discriminated older vs. younger groups excellently and could be used to explore intragroup differences in older adults to predict sleep intervention efficiency depending on their brain complexity

Parasitosis intestinales en escolares de la ciudad de Valencia. Encuesta de prevalencia.

Fundamento: La importancia de la lucha contra las infecciones intestinales entre las que se incluyen las parasitarias radica en su alta prevalencia y su distribuci&oacute;n mundial. El objeto del estudio es conocer la prevalencia de par&aacute;sitos en heces en la poblaci&oacute;n escolar de la ciudad de Valencia y se justifica en el desconocimiento de la endemia parasitaria, combinada con los importantes cambios demogr&aacute;ficos y sociales por el fen&oacute;meno inmigratorio.Material y m&eacute;todo: Se realiza un estudio descriptivo, de corte transversal con distribuci&oacute;n de caracter&iacute;sticas y atributos de los sujetos. Muestra asignada por conglomerados entre la poblaci&oacute;n (64.200 alumnos) asistente a centros de Educaci&oacute;n Infantil (3-5 a&ntilde;os) y Primaria (6-11 a&ntilde;os) segmentada por estacionalidad. Tama&ntilde;o muestral 1.031 ni&ntilde;os, prevalencia esperada 21,8% y error de muestreo 2,5%. Se aplic&oacute; encuesta auto-cumplimentada y toma de muestra &uacute;nica de heces: bote de recogida con fijador y cinta de Graham para detecci&oacute;n de entero-par&aacute;sitos. Resultados: En el segmento estacional primavera-oto&ntilde;o se recuperaron 523 sujetos, (29,8% son poblaci&oacute;n inmigrante). La prevalencia general de infecci&oacute;n fue 27,4%. (IC95%: 23,58-31,22), que alcanza el 40,52% (IC95%: 32,5-47,8) en inmigrantes, RP: 2,45 (IC95%: 1,64-3,67, p&lt;0,0001). Se detectan 11 especies entero-parasitarias, la m&aacute;s frecuente Blastocystis hominis: 14,9%, de los que 57,33% corresponden a escolares inmigrantes RP: 3,16 (IC95%: 2,08-4,79, p&lt;0,0001). Al comparar el origen de los infectados por ciclos escolares se observan diferencias en E.Primaria que se acent&uacute;an con la edad, OR1&ordm;ciclo: 2,6 (IC95%: 1,2-5,4), OR2&ordm;ciclo: 3,15 (IC95%: 1,3-7,3), OR3&ordf;ciclo: 6,44 (IC95%: 2,05-20,18). No se observan diferencias por g&eacute;nero ni globalmente ni entre los inmigrantes.Conclusiones: La prevalencia general de parasitaci&oacute;n observada resulta relevante. En general los datos conocidos coinciden con nuestra encuesta en que el 89% de las parasitosis son por protozoos. Los nematodos suponen un 9% y, de ellos, el m&aacute;s frecuente es E vermicularis. Con otros trabajos consultados, realizados en los a&ntilde;os 90 se comprueba un cambio del patr&oacute;n entero-parasitario y responde al cambio sociodemogr&aacute;fico producido por la inmigraci&oacute;n. La fuerza de asociaci&oacute;n y la relaci&oacute;n infectados/edad en ni&ntilde;os inmigrantes pone de manifiesto la necesidad de una especial vigilancia