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PURPOSE: To analyse the time-to-surgery of a centre of excellence in hip fractures of the elderly and its influence on inpatient mortality and postoperative complications. METHODS: A cross-sectional cohort study was conducted. The sample universe consisted of 4,364 patients admitted to a university clinic in Chía, Colombia during the year 2018 to 2023 with ICD-10 diagnoses corresponding to femur fractures. After eliminating duplicates and application of inclusion and exclusion criteria, the final sample included was 269 patients. Qualitative and quantitative variables were analysed, such as: sex, age, age group, type of fracture, type of surgical procedure, time-to-surgery, time to discharge, inpatient mortality and postoperative complications. RESULTS: The mean time-to-surgery from admission was 70.16 h or 2.92 days (IQR 37-87). Patients were divided into three subgroups of time in which they were taken to surgery: <24 h (11.89%), 24-48 h (33.82%) and > 48 h (54.27%). The overall mortality rate was 1.85% for a total of five deceased patients, two of whom belonged to the 24-48-hour group and three to the > 48 h group. Higher rates of postoperative complications were observed in the > 48-hours group (n: 39, 14.49%), followed by the 24-48-hour group (n: 25, 9.29%) and the < 24-hour group (n: 7, 2.6%). CONCLUSIONS: Patients operated for a hip fracture in > 48 h since admission had a slightly higher rate of postoperative complications. No significant difference was observed regarding inpatient mortality when compared to the 24-48-hour group.

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BACKGROUND/AIMS: Including women of childbearing age in a clinical trial makes it necessary to consider two factors from a bioethical perspective: first, the lack of knowledge about the potential teratogenic effects of an investigational product, and also, the principle of justice not to exclude any population from the benefits of research. The most common way to address this issue is by requiring volunteers to use contraceptives before, during, and a few weeks after the clinical trial. This work presents all the strategies used to promote contraception use and prevent pregnancy during the Alzheimer's Prevention Initiative Autosomal-Dominant Alzheimer's Disease (API ADAD) Colombia clinical trial. Two characteristics of this trial make it of special interest for closely monitoring contraception use. One is that the trial lasted more than 7 years, and the other is that participants could be carriers of the E280A PSEN1 mutation, leading to a mild cognitive impairment as early as their late 30s. METHODS: An individual medical evaluation to select the contraception method that best fits the volunteer was carried out during the screening visit, remitting to the gynecologist when necessary. All non-surgical contraception methods were supplied by the sponsor. Staff were trained on contraception counseling, correctly dispensing contraceptive drugs to volunteers, and identifying, reporting, and following up on pregnancies. Two comprehensive educational campaigns on contraception use were performed, and the intervention included all volunteers. In addition, volunteers were asked on an annual survey to evaluate the dispensing procedure. Finally, the effectiveness of these strategies was retrospectively evaluated, comparing by extrapolation the number of pregnancies presented throughout the trial with the General Fertility Rate in Colombia. RESULTS: A total of 159 female volunteers were recruited. All strategies were implemented as planned, even during the COVID-19 contingency. Ten pregnancies occurred during the evaluation period (2015-2021). Two were planned; the rest were associated with a potential therapeutic failure or incorrect use of contraceptive methods for a contraceptive failure of 0.49% per year. Sixty percent of pregnancies led to an abortion, either miscarriage or therapeutic abortion. However, there was not enough data to associate the pregnancy outcome with the administration of the investigational product. Finally, we observed a lower fertility rate in women participating in the trial compared to the Colombian population. CONCLUSION: The lower rates of contraceptive failure and the decrease in the incidence of pregnancies in women participating in the trial compared to the Colombian population across the 7 years of evaluation suggest that the strategies used in API ADAD Colombia were adequate and effective in addressing contraception use.

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Antioxidants agents play an essential role in the food industry for improving the oxidative stability of food products. In the last years, the search for new natural antioxidants has increased due to the potential high toxicity of chemical additives. Therefore, the synthesis and evaluation of the antioxidant activity in peptides is a field of current research. In this study, we performed a Quantitative Structure Activity Relationship analysis (QSAR) of cysteine-containing 19 dipeptides and 19 tripeptides. The main objective is to bring information on the relationship between the structure of peptides and their antioxidant activity. For this purpose, 1D and 2D molecular descriptors were calculated using the PaDEL software, which provides information about the structure, shape, size, charge, polarity, solubility and other aspects of the compounds. Different QSAR model for di- and tripeptides were developed. The statistic parameters for di-peptides model (R2train = 0.947 and R2test = 0.804) and for tripeptide models (R2train = 0.923 and R2test = 0.847) indicate that the generated models have high predictive capacity. Then, the influence of the cysteine position was analyzed predicting the antioxidant activity for new di- and tripeptides, and comparing them with glutathione. In dipeptides, excepting SC, TC and VC, the activity increases when cysteine is at the N-terminal position. For tripeptides, we observed a notable increase in activity when cysteine is placed in the N-terminal position.

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Machine learning (ML) is revolutionizing groundwater quality research by enhancing predictive accuracy and management strategies for contamination. This comprehensive review explores the evolution of ML technologies and their integration into environmental science, assessing 230 papers to understand the advancements and challenges in groundwater quality research. It reveals that a substantial portion of the research neglects critical preprocessing steps, crucial for model accuracy, with 83 % of the studies overlooking this phase. Furthermore, while model optimization is more commonly addressed, being implemented in 65 % of the papers, there is a noticeable gap in model interpretability, with only 15 % of the research providing explanations for model outcomes. Comparative evaluation of ML algorithms and careful selection of evaluation metrics are deemed essential for determining model fitness and reliability. The review underscores the need for interdisciplinary collaboration, methodological rigor, and continuous innovation to advance ML in groundwater management. By addressing these challenges and implementing solutions, the full potential of ML can be harnessed to tackle complex environmental issues and ensure sustainable groundwater management. This comprehensive and critical review paper can serve as a guiding framework to establish minimum standards for developing ML in groundwater quality studies.

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BACKGROUND: Despite progress made by many countries on the adoption of plain tobacco packaging laws over the last years, low- and middle-income countries, with a large supply of loose cigarettes via informal vendors, remain far behind. AIM: To study the potential effectiveness of plain tobacco packaging and dissuasive cigarette sticks, via willingness-to-pay estimates, when illicit cigarette options are available. METHODS: We conducted a discrete choice experiment (DCE) in which respondents chose licit and illicit products with three attributes: packaging (standard vs. plain packaging), stick design (branded stick vs. stick with warning), and price level. The sample, collected on 12/2021, consisted of 1761 respondents from an internet panel involving smokers and nonsmokers. Conditional logit and latent class models were used to estimate the willingness-to-pay (WTP) to avoid restrictive packaging elements. RESULTS: Nonsmokers are willing to pay USD $5.63 for a pack of cigarettes to avoid plain packaging, which is higher than the actual commercial price of illicit cigarettes (USD $2.40). The WTP increases to USD $12.14 in the presence of illicit alternatives. Smokers are also willing to pay to avoid illicit options, which they also deem riskier, and the presence of such options increases the WTP to avoid plain packaging. However, nonsmokers do not perceive the illicit option as riskier. The dissuasive stick (stick with warning) does not affect perceptions of risk and plays a small role in terms of choice for both smokers and nonsmokers. CONCLUSIONS: Even in the presence of illicit tobacco alternatives, plain packaging seems to be as effective in reducing the attractiveness of tobacco products in Colombia as in other countries that have already adopted it. Given conflicting results on the case for dissuasive sticks, there is a need for more research.

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This study presents the design and development of an ultrasonic sensor as a fundamental tool for characterizing the properties of fluids and biofluids. The analysis primarily focuses on measuring the electrical parameters of the system, which correlate with the density and viscosity of the solutions, in sample volumes of microliters and with high temporal resolution (up to 1 data point per second). The use of this sensor allows the fast and non-destructive evaluation of the viscosity and density of fluids deposited on its free surface. The measurements are based on obtaining the impedance versus frequency curve and the phase difference curve (between current and voltage) versus frequency. In this way, characteristic parameters of the transducer, such as the resonance frequency, phase, minimum impedance, and the quality factor of the resonant system, can characterize variations in density and viscosity in the fluid under study. The results obtained revealed the sensor's ability to identify two parameters sensitive to viscosity and two parameters sensitive to density. As a proof of concept, the unfolding of the bovine albumin protein was studied, resulting in a curve that reflects its unfolding kinetics in the presence of urea.

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BACKGROUND: The COVID-19 pandemic has highlighted a correlation between cardiac complications and elevated cardiac biomarkers, which are linked to poorer clinical outcomes. OBJECTIVE: This study aims to determine the clinical impact of cardiac biomarkers in COVID-19 patients in Latin America. SUBJECTS AND METHODS: The CARDIO COVID 19-20 Registry is a multicenter observational study across 44 hospitals in Latin America and the Caribbean. It included hospitalized COVID-19 patients (n = 476) who underwent troponin, natriuretic peptide, and D-dimer tests. Patients were grouped based on the number of positive biomarkers. RESULTS: Among the 476 patients tested, 139 had one positive biomarker (Group C), 190 had two (Group B), 118 had three (Group A), and 29 had none (Group D). A directly proportional relationship was observed between the number of positive biomarkers and the incidence of decompensated heart failure. Similarly, there was a proportional relationship between the number of positive biomarkers and increased mortality. In Group B, patients with elevated troponin and natriuretic peptide and those with elevated troponin and D-dimer had 1.4 and 1.5 times higher mortality, respectively, than those with elevated natriuretic peptide and D-dimer. CONCLUSIONS: In Latin American COVID-19 patients, a higher number of positive cardiac biomarkers is associated with increased cardiovascular complications and mortality. These findings suggest that cardiac biomarkers should be utilized to guide acute-phase treatment strategies.

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Endophytic fungi (EFs) have emerged as promising modulators of plant growth and stress tolerance in agricultural ecosystems. This review synthesizes the current knowledge on the role of EFs in enhancing the adaptation of crops to abiotic stress. Abiotic stresses, such as drought, salinity, and extreme temperatures, pose significant challenges to crop productivity worldwide. EFs have shown remarkable potential in alleviating the adverse effects of these stresses. Through various mechanisms, including the synthesis of osmolytes, the production of stress-related enzymes, and the induction of plant defense mechanisms, EFs enhance plant resilience to abiotic stressors. Moreover, EFs promote nutrient uptake and modulate the hormonal balance in plants, further enhancing the stress tolerance of the plants. Recent advancements in molecular techniques have facilitated the identification and characterization of stress-tolerant EF strains, paving the way for their utilization in agricultural practices. Furthermore, the symbiotic relationship between EFs and plants offers ecological benefits, such as improved soil health and a reduced dependence on chemical inputs. However, challenges remain in understanding the complex interactions between EFs and host plants, as well as in scaling up their application in diverse agricultural systems. Future research should focus on elucidating the mechanisms underlying endophytic-fungal-mediated stress tolerance and developing sustainable strategies for harnessing their potential in crop production.

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Hybrid scaffolds that are based on PLA and PLA/PMMA with 75/25, 50/50, and 25/75 weight ratios and functionalized with 10 wt.% of bioglass nanoparticles (n-BG) were developed using an electrospinning technique with a chloroform/dimethylformamide mixture in a 9:1 ratio for bone tissue engineering applications. Neat PLA and PLA/PMMA hybrid scaffolds were developed successfully through a (CF/DMF) solvent system, obtaining a random fiber deposition that generated a porous structure with pore interconnectivity. However, with the solvent system used, it was not possible to generate fibers in the case of the neat PMMA sample. With the increase in the amount of PMMA in PLA/PMMA ratios, the fiber diameter of hybrid scaffolds decreases, and the defects (beads) in the fiber structure increase; these beads are associated with a nanoparticle agglomeration, that could be related to a low interaction between n-BG and the polymer matrix. The Young's modulus of PLA/PMMA/n-BG decreases by 34 and 80%, indicating more flexible behavior compared to neat PLA. The PLA/PMMA/n-BG scaffolds showed a bioactive property related to the presence of hydroxyapatite crystals in the fiber surface after 28 days of immersion in a Simulated Body Fluids solution (SBF). In addition, the hydrolytic degradation process of PLA/PMMA/n-BG, analyzed after 35 days of immersion in a phosphate-buffered saline solution (PBS), was less than that of the pure PLA. The in vitro analysis using an HBOF-1.19 cell line indicated that the PLA/PMMA/n-BG scaffold showed good cell viability and was able to promote cell proliferation after 7 days. On the other hand, the in vivo biocompatibility evaluated via a subdermal model in BALC male mice corroborated the good behavior of the scaffolds in avoiding the generation of a cytotoxic effect and being able to enhance the healing process, suggesting that the materials are suitable for potential applications in tissue engineering.

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Decision-making regarding limb amputation represents a significant clinical challenge, especially when the initial evaluation does not coincide with the criteria established in scales used worldwide, as is the case of the MESS scale. This article presents the case of a 24-year-old female patient who was transferred to a university hospital after a road traffic accident with severe and large lesions in the left lower limb. Despite a poor initial prognosis and in-hospital complications, including multiple surgical procedures and foot drop, a favorable recovery was achieved with complete anatomical salvage of the limb at risk. The multidisciplinary approach and intensive rehabilitation were instrumental in achieving a satisfactory functional recovery. This case highlights the importance of considering factors beyond amputation scale scores, as well as the need for comprehensive care to improve outcomes in patients with complex extremity injuries.

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Las heridas de arma de fuego en la región craneofacial representan una actividad con frecuencia en aumento en la actividad médica, y su gravedad depende del tipo de arma utilizada y la distancia del impacto. Entre ellas, las producidas por proyectiles de baja energía producen heridas con un perfil característico, que son una pequeña puerta de entrada con destrucción mínima de tejido inicial, generalmente sin orificio de salida por perder velocidad al contactar con estructuras óseas. El resultado de esto es que el proyectil se aloja en la profundidad del complejo craneofacial, lo cual demanda al cirujano un amplio conocimiento y manejo anatómico para su abordaje. En el presente artículo se describe una novedosa técnica para retiro de proyectil de la fosa pterigomaxilar, guiada por endoscopia a través de un sistema de dilatadores tubulares utilizados para cirugía mínimamente invasiva de columna, en un paciente masculino de 14 años. Luego del retiro del mismo, se continúa con los controles posoperatorios alejados, sin intercurrencias, asintomático e inserto en sus actividades diarias, con una cicatriz mínima, y sin atrofia de la región temporal. Los estudios por imágenes de control visualizan el correcto retiro del cuerpo extraño, con estructuras adyacentes sin lesiones a considerar

Gunshot wounds in the craniofacial region represent an increasingly frequent activity in medical activity, and its severity depends on the type of weapon used and the distance of the impact. Among them, those produced by low-energy projectiles produce wounds with a characteristic profile, which are a small entrance door with minimal initial tissue destruction, generally without an exit hole due to losing speed when contacting bone structures. The result of this is that the projectile lodges deep in the craniofacial complex, which requires the surgeon to have extensive knowledge and anatomical management for its approach. This article describes a novel technique for projectile removal from the pterygomaxillary fossa, guided by endoscopy through a system of tubular dilators used for minimally invasive spine surgery, in a 14-year-old male patient. After its removal, he continued with remote postoperative controls, without complications, asymptomatic and active in his daily activities, with a minimal scar, and without atrophy of the temporal region. Control imaging studies visualize the correct removal of the foreign body, with adjacent structures without injuries to consider.

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Background: Traumatic injury to the long thoracic nerve causes paralysis of the serratus muscle, clinically expressed as winged scapula and functional impairment of the shoulder girdle. Treatment varies according to the severity of the injury, with a focus on early intervention for best results; however, the therapeutic approach remains a challenge at present. Case Description: We present the case of a 32-year-old male patient, athlete, right-handed, presented with bilateral paresis predominantly in the right arm, associated with paresthesia and changes in the coloring of the upper limbs. After being diagnosed with Thoracic Outlet Syndrome and undergoing surgery, vascular symptoms persisted with a significant loss of strength in the right shoulder. Winged scapula was observed and structural lesions were excluded on magnetic resonance imaging. Electromyographic studies confirmed the presumption of traumatic nerve involvement of the long thoracic nerve. Notwithstanding 6 months of physical therapy, there was no improvement, so a nerve transfer from the thoracodorsal nerve to the right long thoracic nerve was chosen. At 12 months, complete resolution of the winged scapula and functional recovery were observed. The patient also experienced a decrease in preoperative pain from 5/10 to 2/10 on the visual analog scale. Conclusion: Nerve transfer from the thoracodorsal nerve to the long thoracic nerve is a safe and effective technique to treat winged scapula due to long thoracic nerve injury.

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Parasitic diseases, predominantly prevalent in developing countries, are increasingly spreading to high-income nations due to shifting migration patterns. The World Health Organization (WHO) estimates approximately 300 million annual cases of giardiasis. The emergence of drug resistance and associated side effects necessitates urgent research to address this growing health concern. In this study, we evaluated over eleven thousand pharmacological compounds sourced from the FDA database to assess their impact on the TATA-binding protein (TBP) of the early diverging protist Giardia lamblia, which holds medical significance. We identified a selection of potential pharmacological compounds for combating this parasitic disease through in silico analysis, employing molecular modeling techniques such as homology modeling, molecular docking, and molecular dynamics simulations. Notably, our findings highlight compounds DB07352 and DB08399 as promising candidates for inhibiting the TBP of Giardia lamblia. Also, these compounds and DB15584 demonstrated high efficacy against trophozoites in vitro. In summary, this study identifies compounds with the potential to combat giardiasis, offering the prospect of specific therapies and providing a robust foundation for future research.

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An epidural hematoma is a rare but devastating complication after interventional pain procedures. The etiology is multifactorial, including anatomical variations, inherited coagulation disorders, and consumption of anticoagulants or antiplatelet substances. Specifically, in regard to platelet aggregation, the consumption of herbal medicine is often forgotten as a potential cause for coagulation profile disorders, potentially leading to an epidural hematoma. We present the case of a patient who developed an epidural hematoma after a cervical epidural block, most likely associated with daily "red clover" consumption.

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Introduction: A major sublineage within the Mycobacterium tuberculosis (MTB) LAM family characterized by a new in-frame fusion gene Rv3346c/55c was discovered in Rio de Janeiro (Brazil) in 2007, called RDRio, associated to drug resistance. The few studies about prevalence of MTB RDRio strains in Latin America reported values ranging from 3% in Chile to 69.8% in Venezuela, although no information is available for countries like Ecuador. Methods: A total of 814 MTB isolates from years 2012 to 2016 were screened by multiplex PCR for RDRio identification, followed by 24-loci MIRU-VNTR and spoligotyping. Results: A total number of 17 MTB RDRio strains were identified, representing an overall prevalence of 2.09% among MTB strains in Ecuador. While 10.9% of the MTB isolates included in the study were multidrug resistance (MDR), 29.4% (5/17) of the RDRio strains were MDR. Discussion: This is the first report of the prevalence of MTB RDRio in Ecuador, where a strong association with MDR was found, but also a very low prevalence compared to other countries in Latin America. It is important to improve molecular epidemiology tools as a part of MTB surveillance programs in Latin America to track the transmission of potentially dangerous MTB stains associated to MDR TB like MTB RDRio.

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Introducción: La esofagectomía es actualmente el tratamiento curativo del cáncer de esófago. El objetivo de este trabajo es conocer los resultados de la esofaguectomía mínimamente invasiva a corto y medio plazo en pacientes intervenidos de carcinoma epidermoide y adenocarcinoma de esófago en nuestro hospital. Material y Métodos: Se recogieron 19 pacientes desde enero de 2020 hasta junio de 2021 y se realizó el seguimiento a todos ellos durante 20 meses. Se recogieron diferentes variables relacionadas con el paciente, el tumor, la cirugía y referentes al postoperatorio. Los datos fueron almacenados y procesados usando el software estadístico R-Comander asumiendo un error α de 0,05. Resultados: La mediana de estancia hospitalaria total fue de 29 días. Seis pacientes, precisaron de reingreso en Reanimación: dos por shock séptico secundario a la fuga de anastomosis grado III, uno por hemorragia digestiva alta y los tres por insuficiencia respiratoria. A los 90 días reingresaron un 5,3% del total de pacientes. No se produjeron fallecimientos en los tres meses siguientes a la cirugía. Todos los pacientes presentaron una supervivencia mayor de seis meses. La supervivencia global a seis, 12 y 18 meses se sitúa en 100, 84 y 63%. La supervivencia libre de enfermedad a los tres meses fue del 84%, a los 6 meses del 63% y al año el 58%. Discusión: Los resultados obtenidos en nuestro estudio coinciden con lo que hay reflejado en la literatura. Por tanto, la esofagectomía mínimamente invasiva es una técnica efectiva en el tratamiento del cáncer de esófago.

Introduction: Oesophagectomy is currently the curative treatment for oesophageal cancer. The aim of this study is to know the results of minimally invasive oesophagectomy in the short and medium term in patients operated on for squamous cell carcinoma and adenocarcinoma of the oesophagus in our hospital. Material and Methods: 19 patients were collected from January 2020 to June 2021 and all of them were followed up for 20 months. Different variables related to the patient, tumour, surgery and postoperative period were collected. Data were stored and processed using R-Comander statistical software assuming an α-error of 0.05. Results: The median total hospital stay was 29 days. Six patients required readmission to resuscitation: two for septic shock secondary to grade III anastomotic leak, one for upper gastrointestinal haemorrhage and three for respiratory failure. At 90 days, 5.3% of the total number of patients were re-admitted. There were no deaths in the three months following surgery. All patients had a survival of more than six months. Overall survival at six, 12 and 18 months was 100, 84 and 63%. Disease-free survival at three months was 84%, at six months 63% and at one year 58%. Discussion: The results obtained in our study coincide with those reported in the literature. Minimally invasive oesophagectomy is therefore an effective technique in the treatment of oesophageal cancer.

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Background: Coronavirus disease 2019 (COVID-19) has had a significant impact on dermatology, but to date no bibliometric analysis of this field has been identified. Therefore, the aim of this study was to perform a bibliometric indicator analysis of the worldwide scientific production of COVID-19 in dermatology. Materials and Methods: An advanced bibliographic search was performed in the Scopus database to identify articles on COVID-19 and dermatology from 2020 to 2021. The collected information was analysed with SciVal software. Bibliometric data were described through figures and summary tables. Results: A total of 1448 documents were collected and analysed. Torello Lotti was the author with the greatest scientific production; however, Esther Freeman had the greatest impact. Harvard University was the institution with the highest number of published articles. Most papers were published in the first quartiles. The United States and Italy were the leading countries in terms of production. Articles with international collaboration had the highest impact. Conclusion: Articles related to dermatology and COVID-19 are mostly published with American and Italian affiliations. In addition, there has been an increase in the distribution of articles published in the first quartile, which would reflect a growing interest in the community. Publications with international collaboration reported the highest impact, so future authors should take this into account.

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Coronavirus disease 2019 (COVID-19) was considered a major public health burden worldwide. Multiple studies have shown that susceptibility to severe infections and the development of long-term symptoms is significantly influenced by viral and host factors. These findings have highlighted the potential of host genetic markers to identify high-risk individuals and develop target interventions to reduce morbimortality. Despite its importance, genetic host factors remain largely understudied in Latin-American populations. Using a case-control design and a custom next-generation sequencing (NGS) panel encompassing 81 genetic variants and 74 genes previously associated with COVID-19 severity and long-COVID, we analyzed 56 individuals with asymptomatic or mild COVID-19 and 56 severe and critical cases. In agreement with previous studies, our results support the association between several clinical variables, including male sex, obesity and common symptoms like cough and dyspnea, and severe COVID-19. Remarkably, thirteen genetic variants showed an association with COVID-19 severity. Among these variants, rs11385942 (p < 0.01; OR = 10.88; 95% CI = 1.36-86.51) located in the LZTFL1 gene, and rs35775079 (p = 0.02; OR = 8.53; 95% CI = 1.05-69.45) located in CCR3 showed the strongest associations. Various respiratory and systemic symptoms, along with the rs8178521 variant (p < 0.01; OR = 2.51; 95% CI = 1.27-4.94) in the IL10RB gene, were significantly associated with the presence of long-COVID. The results of the predictive model comparison showed that the mixed model, which incorporates genetic and non-genetic variables, outperforms clinical and genetic models. To our knowledge, this is the first study in Colombia and Latin-America proposing a predictive model for COVID-19 severity and long-COVID based on genomic analysis. Our study highlights the usefulness of genomic approaches to studying host genetic risk factors in specific populations. The methodology used allowed us to validate several genetic variants previously associated with COVID-19 severity and long-COVID. Finally, the integrated model illustrates the importance of considering genetic factors in precision medicine of infectious diseases.

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This work reports the dielectric behavior of the biopolymer ethyl cellulose (EC) observed from transient currents experiments under the action of a direct current (DC) electric field (~107 V/m) under vacuum conditions. The viscoelastic response of the EC was evaluated using dynamic mechanical analysis (DMA), observing a mechanical relaxation related to glass transition of around ~402 K. Furthermore, we propose a mathematical framework that describes the transient current in EC using a fractional differential equation, whose solution involves the Mittag-Leffler function. The fractional order, between 0 and 1, is related to the energy dissipation rate and the molecular mobility of the polymer. Subsequently, the conduction mechanisms are considered, on the one hand, the phenomena that occur through the polymer-electrode interface and, on the other hand, those which manifest themselves in the bulk material. Finally, alternating current (AC) conductivity measurements above the glass transition temperature (~402 K) and in a frequency domain from 20 Hz to 2 MHz were carried out, observing electrical conduction described by the segmental movements of the polymeric chains. Its electrical properties also position EC as a potential candidate for electrical, electronics, and mechatronics applications.

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The sex-biased dispersal and kinship dynamics are important factors shaping the spatial distribution of individuals and are key parameters affecting a variety of ecological and evolutionary processes. Here, we studied the spatial distribution of related individuals within a population of corn mice Calomys musculinus in a seasonal cycle to infer dispersal patterns. The sampling was carried out from spring 2005 to winter 2006 in field borders of intensively managed agroecosystems. Genotyping data from 346 individuals with 9 microsatellites showed spatial genetic structure was weak for males, but not for females. The results indicate a complex spatial kinship dynamic of related females across all seasons. Which, contrary to our expectations, dispersal distances decrease with the increase of the population abundance. Meanwhile, male dispersal distances were greater when population abundance increased and thus the availability of active females. Males disperse greater distances to mate and sire offspring with distant females as a possible inbreeding avoidance mechanism. This study shows that C. musculinus is capable of much greater scattering distances than previously reported and that dispersal occurs fluidly and without barriers across the agroecosystem. The indirect benefit of dispersal on individual fitness could be related to relaxing the competition in the natal area and increasing the mating rate. Our study highlights the value of combining genetic relatedness, fieldwork observations, and behavioral data to estimate dispersal at a fine geographical scale.