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1.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230111, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38705186

RESUMEN

Global pollinator decline urgently requires effective methods to assess their trends, distribution and behaviour. Passive acoustics is a non-invasive and cost-efficient monitoring tool increasingly employed for monitoring animal communities. However, insect sounds remain highly unexplored, hindering the application of this technique for pollinators. To overcome this shortfall and support future developments, we recorded and characterized wingbeat sounds of a variety of Iberian domestic and wild bees and tested their relationship with taxonomic, morphological, behavioural and environmental traits at inter- and intra-specific levels. Using directional microphones and machine learning, we shed light on the acoustic signature of bee wingbeat sounds and their potential to be used for species identification and monitoring. Our results revealed that frequency of wingbeat sounds is negatively related with body size and environmental temperature (between-species analysis), while it is positively related with experimentally induced stress conditions (within-individual analysis). We also found a characteristic acoustic signature in the European honeybee that supported automated classification of this bee from a pool of wild bees, paving the way for passive acoustic monitoring of pollinators. Overall, these findings confirm that insect sounds during flight activity can provide insights on individual and species traits, and hence suggest novel and promising applications for this endangered animal group. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Asunto(s)
Acústica , Alas de Animales , Animales , Abejas/fisiología , Alas de Animales/fisiología , Vuelo Animal/fisiología , Vocalización Animal/fisiología , Polinización , Sonido
2.
Sensors (Basel) ; 23(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36617145

RESUMEN

A Critical Adaptive Distributed Embedded System (CADES) is a group of interconnected nodes that must carry out a set of tasks to achieve a common goal, while fulfilling several requirements associated with their critical (e.g., hard real-time requirements) and adaptive nature. In these systems, a key challenge is to solve, in a timely manner, the combinatorial optimization problem involved in finding the best way to allocate the tasks to the available nodes (i.e., the task allocation) taking into account aspects such as the computational costs of the tasks and the computational capacity of the nodes. This problem is not trivial and there is no known polynomial time algorithm to find the optimal solution. Several studies have proposed Deep Reinforcement Learning (DRL) approaches to solve combinatorial optimization problems and, in this work, we explore the application of such approaches to the task allocation problem in CADESs. We first discuss the potential advantages of using a DRL-based approach over several heuristic-based approaches to allocate tasks in CADESs and we then demonstrate how a DRL-based approach can achieve similar results for the best performing heuristic in terms of optimality of the allocation, while requiring less time to generate such allocation.

3.
Sensors (Basel) ; 22(18)2022 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-36146448

RESUMEN

Distributed Embedded Systems (DESs) carrying out critical tasks must be highly reliable and hard in real-time. Moreover, to operate in dynamic operational contexts in an effective and efficient manner, they must also be adaptive. Adaptivity is particularly interesting from a dependability perspective, as it can be used to develop dynamic fault tolerance mechanisms, which, in combination with static ones, make it possible to provide better and more efficient fault tolerance. However, constructing a DES with such complexity presents many challenges. This is because all the mechanisms that support fault tolerance, real-time, and adaptivity must be designed to operate in a coordinated manner. This paper presents the Dynamic Fault Tolerance for Flexible Time-Triggered Ethernet (DFT4FTT), a self-reconfigurable infrastructure for implementing highly reliable adaptive DES. Here, we describe the design of its hardware and software architecture and the main set of mechanisms, with a focus on fault tolerance.

4.
Naturwissenschaften ; 109(3): 29, 2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-35622169

RESUMEN

Driven by natural and sexual selection, calling behaviours and call parameters can vary within and between individuals. Phenotypic plasticity can be influenced by environmental conditions (e.g., temperature), size, body condition, and age. Crickets have been classic model organisms for studying the evolution of acoustic communication, but previous studies have focused on field crickets, for which males call at a low frequency, while females exhibit phonotaxis. This study holistically investigated the plasticity of calling behaviours and call parameters across a temperature gradient in a species of lebinthine crickets and examined plasticity between and within individuals. These crickets exhibit a unique communication system, including males calling at a near-ultrasonic frequency while actively searching for females. Ten recording assays at different temperatures were done on males of different sizes and body conditions, half of the assays when the males first became adults and another half 1 month later. Size, body condition, and age group of male crickets, as well as the ambient temperature, had different effects on different calling behaviours (e.g., number of songs produced) and call parameters (e.g., call duration, trill syllable period), even when the acoustic traits were correlated. The crickets also exhibited acclimatisation to the experimental conditions in their calling behaviours and acoustic traits to repeated assays. We also found that calling behaviours were less repeatable than temporal call parameters (e.g., call duration, trill duration), which in turn, were less repeatable than the spectral call parameter (dominant frequency).


Asunto(s)
Gryllidae , Acústica , Adaptación Fisiológica , Animales , Femenino , Humanos , Masculino , Fenotipo , Vocalización Animal
5.
Polymers (Basel) ; 14(1)2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-35012225

RESUMEN

We explore the foam extrusion of expanded polypropylene with a long chain branched random co-polypropylene to make its production process simpler and cheaper. The results show that the presence of long chain branches infer high melt strength and, hence, a wide foamability window. We explored the entire window of foaming conditions (namely, temperature and pressure) by means of an ad-hoc extrusion pilot line design. It is shown that the density of the beads can be varied from 20 to 100 kg/m3 using CO2 and isobutane as a blowing agent. The foamed beads were molded by steam-chest molding using moderate steam pressures of 0.3 to 0.35 MPa independently of the closed cell content. A characterization of the mechanical properties was performed on the molded parts. The steam molding pressure for sintering expanded polypropylene beads with a long chain branched random co-polypropylene is lower than the one usually needed for standard polypropylene beads by extrusion. The energy saving for the sintering makes the entire manufacturing processes cost efficient and can trigger new applications.

6.
Polymers (Basel) ; 13(21)2021 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-34771399

RESUMEN

Different percentages of an elastomeric phase of styrene-ethylene-butylene-styrene (SEBS) were added to a polystyrene (PS) matrix to evaluate its nucleating effect in PS foams. It has been demonstrated that a minimum quantity of SEBS produces a high nucleation effect on the cellular materials that are produced. In particular, the results show that by adding 2% of SEBS, it is possible to reduce the cell size by 10 times while maintaining the density and open cell content of the foamed materials. The influence of this polymeric phase on the glass transition temperature (Tg) and the shear and extensional rheological properties has been studied to understand the foaming behavior. The results indicate a slight increase in the Tg and a decrease of the shear viscosity, extensional viscosity, and strain hardening coefficient as the percentage of SEBS increases. Consequently, an increase in the density and a deterioration of the cellular structure is detected for SEBS amounts higher than 3%.

7.
Menopause ; 24(8): 938-946, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28195990

RESUMEN

OBJECTIVES: This study explored the multidimensional outcomes that resulted from the adherence to regular exercise among previously sedentary postmenopausal women. The exercise was managed through a supervised, multicomponent, adapted approximately 20-week program in a suited health promotion intervention. METHODS: A multigroup, mixed-design study with between-group (intervention, sedentary, and active women) and within-subject measures (baseline, postintervention, and 3- and 12-month follow-ups) was conducted using intention-to-treat methodology. The Cervantes Scale assessed health-related quality of life (HRQoL), and several indicators of cardio-metabolic status and fitness were also assessed. RESULTS: After the intervention, the participants experienced positive changes in short and long-term physical and mental health, with significant enhancements in several HRQoL dimensions, particularly mental well-being and menopause-related health and subdomains. Improvements were maintained or continued (eg, mental well-being) throughout the period, leading up to the 12-month follow-up. These outcomes were accompanied by significant improvements in cardio-metabolic status and fitness, including weight, body mass index, cardio-respiratory fitness, and flexibility. CONCLUSIONS: Our findings parallel previous empirical evidence showing the benefits associated with regular exercise, and add evidence to the association of positive outcomes in HRQoL with improvements in cardio-metabolic health and fitness status after the adoption of an active lifestyle.


Asunto(s)
Terapia por Ejercicio , Posmenopausia/psicología , Calidad de Vida , Femenino , Promoción de la Salud , Humanos , Persona de Mediana Edad , Aptitud Física , Estudios Prospectivos , España , Resultado del Tratamiento
8.
J Phys Act Health ; 14(5): 336-343, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28169553

RESUMEN

BACKGROUND: This study explored multidimensional outcomes that were derived from the adherence to regular exercise among previously sedentary postmenopausal 45 to 64 years old women who engaged in a ~20-week exercise program. METHODS: A randomized controlled trial with between-group (intervention and control women) and within-subject measures (baseline, postintervention, and 3-month and 12-month follow-ups) was conducted. HRQoL and several indicators of cardio-metabolic status and fitness were assessed. RESULTS: After the intervention, the participants experienced a positive change in their short and long-term physical and mental health, with significant enhancements in several HRQoL dimensions, particularly mental well-being (23.3% of change) and menopause-related health and subdomains (17.0% of change) (P < .01). Improvements were maintained or continued (eg, mental well-being) overtime. These outcomes were accompanied by significant improvements in cardio-metabolic status and fitness, including weight, BMI, cardio-respiratory fitness and flexibility (up to 16.2% of change, P < .05). After the intervention, the intervention group exhibited better HRQoL than the control group at each of the measurement phases. Between-group differences were also observed for some indicators of cardiovascular health and flexibility. CONCLUSIONS: Our findings add evidence on the association of positive outcomes on HRQoL with improvements in cardio-metabolic health and fitness status after the adoption of an active lifestyle.


Asunto(s)
Ejercicio Físico , Promoción de la Salud/métodos , Aptitud Física/fisiología , Calidad de Vida , Envejecimiento/fisiología , Femenino , Humanos , Estilo de Vida , Salud Mental , Persona de Mediana Edad , Posmenopausia , Estudios Prospectivos
9.
Magn Reson Med ; 78(4): 1464-1468, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-27779778

RESUMEN

PURPOSE: This study describes a new methodology-the cold pressor gel test (CPGT)-for delivering an accessible experimental pain stimulus, which is reproducible and safe for functional MRI (fMRI). METHODS: The cold pressor test was modified to put safety precautions into the CPGT. The material used is cool gelled water with a thickening product, which provides a stable temperature at 0.2 °C. Thirteen women with chronic pelvic pain were scanned using a 3 Tesla (T) MR scanner equipped with a 12-channel head coil. Changes in BOLD activation during cold-induced pain were estimated. RESULTS: The results have demonstrated that gel substances maintain a stable temperature during the experiment, resulting in an insignificant variation. Before the experiment, the mean temperature was 0.2 ± 0.11 °C, and at the end it was 0.7 ± 0.15 °C. The time taken by participants to reach the maximum level of pain during the CPGT was 56.92 ± 11.09 s. The pain intensity during the experiments was 6.92 ± 1.66 on the visual analog scale (VAS). The fMRI analysis showed significant BOLD activation in the main brain regions involved in chronic pain processing. CONCLUSION: The CPGT is an experimental tool to deliver pain that is easily reproducible, particularly in brain functional imaging studies. Moreover, it is cost-effective, safe, and compatible with fMRI. Magn Reson Med 78:1464-1468, 2017. © 2016 International Society for Magnetic Resonance in Medicine.


Asunto(s)
Investigación Biomédica/métodos , Frío/efectos adversos , Imagen por Resonancia Magnética/métodos , Dolor/fisiopatología , Adulto , Investigación Biomédica/normas , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética/normas , Persona de Mediana Edad , Reproducibilidad de los Resultados
10.
Chem Commun (Camb) ; 52(14): 2905-8, 2016 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-26780935

RESUMEN

The intermolecular reaction of allenamides with aldehydes is reported. The designed approach relies on gold(i) and organocatalysis for activating the allenamides and the aldehydes respectively. Conditions to achieve an enantioselective version of this intermolecular reaction are defined.

11.
Maturitas ; 77(2): 93-110, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24289897

RESUMEN

Women's care during perimenopause and postmenopause is taking new paths to help women cope with both somatic manifestations and changes related to psychological and social factors. An updated, systematic review was conducted on non-pharmacological psychosocial interventions with regard to peri- and postmenopause. Several databases complemented with reference lists and reviews were used to perform a literature search of any relevant article. Studies were selected if they included psychoeducational programmes, health education and promotion and cognitive-behavioural techniques applied to peri- or postmenopausal women, independently of study design, main outcomes and intervention comparators. A total of 33 reports and 3 relevant reviews published between 1987 and 2013 were included. Psychosocial options are promising intervention options for self-management and self-care, as they provide multiple benefits with no side effects. Moreover, these options are recommended for women in clinical, subclinical and asymptomatic groups, as they offer women the agency and skills necessary to manage and relieve menopausal symptoms, as well as provide information and alternatives to prevent menopausal symptoms and to have a more positive experience during these life stages. These options do more than reduce distress and complaints, as they allow women in any condition to enjoy enhanced health, well-being and quality of life. Moreover, these options are accompanied by important cost reductions in pharmaceutical investment and healthcare. Nevertheless, several issues remain controversial or have scarcely been investigated, and additional high-quality research should address these issues properly in the future. Despite these limitations and the weaknesses of the review, the findings of this review are interesting and positive. Thus, we encourage women-focused institutions and policies (e.g., healthcare centres, public organisations and women's associations) to offer psychosocial interventions to peri- and postmenopausal women within a comprehensive healthcare paradigm.


Asunto(s)
Terapia Cognitivo-Conductual , Educación en Salud , Promoción de la Salud , Menopausia/psicología , Toma de Decisiones , Femenino , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
12.
Rev. fitoter ; 12(1): 37-44, jul. 2012. tab, ilus
Artículo en Español | IBECS | ID: ibc-110272

RESUMEN

El interés por la fitoterapia en el tratamiento dela vulvovaginitis es reciente y se debe principalmente a las reacciones adversas, la toxicidad y las recidivas que se producen que se producen a menudo con los tratamientos farmacológicos habituales. Se realizó una búsqueda en bases bibliográficas médicas y páginas web de medicina alternativa, detectándose un total de 13 ensayos clínicos. Tres de ellos están escritos en chino, de los que sólo fue posible obtener el resumen. Se valoró su calidad metodológica, infiriéndose el nivel de evidencia. Se comentan los hallazgos fundamentales (AU)


The interest of Phytotherapy in the treatment of vulvovaginitis is recent and it is mainly due to the adverse reactions, toxicity and relapses that are often produced by standard drug therapies. A literature search using medical bibliography databases and alternative medicine websites detected a total of 13 clinical trials. Three of them were in Chinese, for which it was only possible to obtain the summary. Methodological quality was assessed, inferring the level of evidence. Key findings are discussed. We emphasize the usefulness of green tea catechins in the syntomatic treatment of genital warts (AU)


Asunto(s)
Humanos , Femenino , Medicina Basada en la Evidencia/métodos , Medicina Basada en la Evidencia/tendencias , Fitoterapia/métodos , Fitoterapia/normas , Fitoterapia , Enfermedades de los Genitales Femeninos/tratamiento farmacológico , Camellia sinensis , Vulvovaginitis/terapia , Catequina/uso terapéutico , Medicina Basada en la Evidencia/organización & administración , Medicina Basada en la Evidencia/normas , Catequina/metabolismo , Catequina/farmacocinética , Condiloma Acuminado/terapia
13.
Med Sci Monit ; 14(12): CR598-603, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19043366

RESUMEN

BACKGROUND: The aim of the study was to determine whether a predictive value for the diagnosis of gestational diabetes mellitus (GDM) could be established using different glucose screening test thresholds in Mexican urban pregnant women. MATERIAL/METHODS: A group of 635 pregnant women (12-33 weeks of gestation) with serum glucose screening values of > or = 7.2 mmol (> or = 130 mg/dl) were evaluated with a 100-g 3-h oral glucose tolerance test (OGTT). The positive predictive values (PPVs) for serum glucose screening values of > or = 7.2 mmol to > or = 11.1 mmol (> or = 130 to > or = 200 mg/dl), age, and pregestational BMI were calculated. RESULTS: Of the women, 304 (47.8%) had a normal OGTT, 126 (19.8%) had impaired glucose tolerance, and 205 (32.3%) had GDM. A serum glucose screening value of > or = 9.4 mmol (> or = 170 mg/dl) had a positive predictive value (PPV) of 0.85 and the relative risk for GDM was 6.62 (95%CI: 4.40-9.97, p=0.001). Omission of the 3-h value during OGTT yielded a sensitivity of 91.2% (187/205). CONCLUSIONS: In this group of Mexican urban pregnant women, a serum glucose screening value of > or = 9.4 mmol (> or = 170 mg/dl) had a PPV of 85%. An algorithm is proposed to reduce the number of OGTTs performed in pregnant women attending prenatal care by 36.2%.


Asunto(s)
Diabetes Gestacional/diagnóstico , Tamizaje Masivo/métodos , Población Urbana , Algoritmos , Glucemia/análisis , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , México , Embarazo
14.
Ginecol Obstet Mex ; 76(3): 178-81, 2008 Mar.
Artículo en Español | MEDLINE | ID: mdl-18798414

RESUMEN

Incidence of Behçet disease in USA is 0.12 in 100,000; but in Mexico there are just two isolated cases. This paper reports a case of a 30 year-old female, who, when 26, had vaginal ulcers. She received antimicrobial therapy during four years. In March 2007 she came to author's hospital with a cervical vaginitis diagnose study, and presenting thorax with venous collateral circulation secondary to superior and inferior cava vein thrombosis. Colposcopy and vaginal wall biopsy were practiced and found chronic ulcer with vascular damage; oral ulcers were found too, and Pathergy test was positive. Currently there is no ocular damage. Patient received azathioprine therapy without improvement, later she received anticoagulant therapy with corticoids and has good evolution.


Asunto(s)
Síndrome de Behçet/complicaciones , Úlcera/etiología , Adulto , Anticoagulantes/uso terapéutico , Azatioprina/uso terapéutico , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/epidemiología , Femenino , Humanos , Inmunosupresores/uso terapéutico , Úlceras Bucales/etiología , Prednisona/uso terapéutico , Embarazo , Síndrome de la Vena Cava Superior/etiología , Úlcera/tratamiento farmacológico , Enfermedades Vaginales/tratamiento farmacológico , Enfermedades Vaginales/etiología , Vena Cava Inferior , Trombosis de la Vena/etiología , Trombosis de la Vena/prevención & control
15.
Ginecol Obstet Mex ; 75(11): 691-4, 2007 Nov.
Artículo en Español | MEDLINE | ID: mdl-18697445

RESUMEN

It is a 27 years old patient, childbirths three, menarche 13 years, regular cycles, with dismenorrea incapacitante twice a year, referring light dispareunia, which was refered a our hospital. She had been hospitalized three days ago presenting left neumotorax, it was the third time she have had the same clinical square in the last four months, she had a neumotorax of 40%, Ca 125 de 102 U/ml, the pelvic ultrasound reported like positive anecoica image of five for four centimeters, through a toracoscopy in which reported two focuses endometriosicos of aproximately 0.5 centimeters, from which a biopsy was obtained and reported tissue endometrium in lung parenchyma.


Asunto(s)
Endometriosis/complicaciones , Endometriosis/patología , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/patología , Neumotórax/complicaciones , Adulto , Endometriosis/cirugía , Femenino , Humanos , Neoplasias Pulmonares/cirugía , Neumotórax/diagnóstico por imagen , Neumotórax/cirugía , Tomografía Computarizada por Rayos X
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