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La Selección Genómica (SG) es un método que emplea datos genómicos para estimar valores de cría y clasificar a los candidatos para la selección. A pesar de las numerosas ventajas, su aplicación en programas de mejoramiento de ganado vacuno permanece en etapas incipientes en muchos sistemas ganaderos desarrollados en ambientes tropicales y subtropicales, como los de Paraguay. Las simulaciones computacionales son herramientas poderosas, que mejoran nuestra comprensión de las aplicaciones de la SG en diferentes escenarios y son invaluables como paso inicial antes de implementar esta técnica en programas "reales" de mejoramiento genético. En este estudio, se emplearon datos reales de polimorfismos de nucleótido único (SNPs) de las razas Indicus y Taurus para simular tres esquemas de cruzamiento: cruces F1, absorbente y cruzamientos rotacionales. Se seleccionaron fenotipos para rasgos relacionados con la fuerza de corte, el crecimiento y la tolerancia. Se comparó la precisión predictiva de tres chips de SNP de 50k que diferían en las metodologías de selección: selección aleatoria, selección basada en diferencias mínimas de frecuencia alélica entre razas y selección basada en diferencias mínimas de frecuencia alélica entre razas con un umbral de 0.09 en Taurus. Los hallazgos indican que el cruce rotacional demuestra una precisión predictiva óptima (0.38), mientras que la selección de marcadores basada en diferencias de frecuencia alélica entre razas (0.18 y 0.17, respectivamente) no beneficia significativamente a las predicciones.

Breast cancer survivorship is a recognized risk factor for sexual dysfunction, with various clinical, sociocultural, and psychological factors potentially interacting differently across populations. This study compared sexual dysfunction, anxiety, and depression between females with breast cancer and those without, aiming to identify associated factors. A total of 362 females participated, including 227 with sexual dysfunction and 135 controls. Among them, 195 are breast cancer survivors, while 167 have no personal history of cancer. Key variables were analyzed using Student’s t-test for quantitative data and Fisher’s exact test for categorical data, while logistic regression models were used to assess the association between sexual dysfunction and various factors. Multivariate analysis revealed that, in sexually active females, breast cancer survivorship increased the odds of sexual dysfunction 2.7-fold (95% CI: 1.17–6.49; p = 0.020). Anxiety was significantly associated with sexual dysfunction, regardless of cancer status (AdOR 6.00; 95% CI: 2.50–14.43; p < 0.001). The interaction between cancer survival and anxiety further increased the odds of sexual dysfunction by more than 11-fold (AdOR 11.55; 95% CI: 3.81–35.04; p < 0.001). Additionally, obesity was found to be a protective factor among cancer survivors (AdOR 0.149; 95% CI: 0.027–0.819; p = 0.029). In conclusion, breast cancer has a significant impact on sexual function, with psychological factors like anxiety playing a crucial role. Addressing these issues requires a holistic, patient-centered approach that considers the complex interplay of physical, emotional, and sociocultural factors.

Reducing carbon emissions is a critical issue for the near future as climate change is an imminent reality. To reduce our carbon footprint, society must change its habits and behaviours to optimise energy consumption, and the current progress in embedded systems and artificial intelligence has the potential to make this easier. The smart building concept and intelligent energy management are key points to increase the use of renewable sources of energy as opposed to fossil fuels. In addition, cyber-physical systems (CPSs) provide an abstraction of the management of services that allows the integration of both virtual and physical systems in a seamless control architecture. In this paper, we propose to use multiagent reinforcement learning (MARL) to model the CPS services control plane in a smart house, with the purpose of minimising, by shifting or shutdown services, the use of non-renewable energy (fuel generator) by exploiting solar production and batteries. Furthermore, our proposal dynamically adapts its behaviour in real time according to current and historic energy production, thus being able to handle occasional changes in energy production due to meteorological phenomena or unexpected energy consumption. In order to evaluate our proposal, we have developed an open-source smart building energy simulator and deployed our use case. Finally, several simulations with different configurations are evaluated to verify the performance. The simulation results show that the reinforcement learning solution outperformed the priority-based and the heuristic-based solutions in both power consumption and adaptability in all configurations.

Background: This study investigates how mental toughness and adaptability in game matches contribute to the resiliency of Sepaktakraw athletes in the field of competitive challenges. Objectives: This study explored the impact of mental toughness and adaptability on the resilience of Sepaktakraw athletes facing competitive challenges. Methods: Conducted during the 2023-2024 academic year, the research involved 60 male athletes aged 18-22 from Batangas State University, each with 4-8 years of experience in the sport. Using a descriptive-correlational approach, the study assessed athletes’ perceptions of mental toughness and resilience through the 4C’s Psychological framework—Challenge, Commitment, Control, and Confidence. Results: Findings highlighted the role of mental toughness and adaptability in strengthening athletes’ resilience. Consequently, the study proposed tailored training activities focused on enhancing these traits in gameplay. Presented in tabular form, each activity includes specific objectives designed to help athletes develop coping mechanisms for setbacks, maintain focus, and improve mental toughness. Conclusion: By engaging in these targeted training exercises, teamwork, and community interactions, athletes are expected to build the resilience needed to overcome competitive challenges and achieve success in Sepaktakraw.

The methylenetetrahydrofolate reductase (MTHFR) gene 677C➔T polymorphism is capable of altering folate metabolism and can modify certain neoplasia risk. Reports have suggested that folate can have an influence on bone development and so it is of interest to know if the MTHFR 677C➔T polymorphism is associated with the malignant transformation process of this tissue. The polymorphism was determined in 55 patients with osteosarcoma and in 180 healthy individuals. Compared with C/T+C/C genotypes, a 3.7-fold reduction in osteosarcoma probability is possible with the T/T genotype (OR 0.27, CI 95% 0.07–0.82). Undoubtedly, further studies, utilizing large samples and carried out on different populations, are necessary to confirm these results.

BackgroundHypertrophic cardiomyopathy (HCM) is a genetic disorder for which first-line treatments for obstructive HCM (oHCM) include beta-blockers, non-dihydropyridine calcium channel blockers, and disopyramide for refractory cases. Mavacamten, a selective cardiac myosin inhibitor, is indicated for symptomatic oHCM to improve functional capacity and symptoms. Use of disopyramide and mavacamten together is not recommended due to concerns of additive negative inotropic effects. Transitioning from disopyramide to mavacamten may be preferred to avoid adverse effects and frequent administration, however, the best approach for making the transition has not been established.CasesWe present a series of seven patients with oHCM who transitioned from disopyramide to mavacamten and underwent echocardiograms mandated by a Risk Evaluation and Mitigations Strategies program. Two methods were employed. The first approach, involving washout of disopyramide before starting mavacamten, resulted in worsening of heart failure symptoms in the first two cases. The second approach, involving tapering disopyramide when starting mavacamten, was successfully implemented in the last five cases, with no adverse effects or worsening of systolic dysfunction.ConclusionOur method of tapering disopyramide when starting mavacamten using a stepwise approach is feasible and safe. Our report fulfills an unmet need by serving as a guide for other clinicians who seek to transition their patients from disopyramide to mavacamten.

Influenza A virus (IAV) continuously threatens animal and public health globally, with swine serving as a crucial reservoir for viral reassortment and evolution. In Chile, H1N2 and H3N2 subtypes were introduced in the swine population before the H1N1 2009 pandemic, and the H1N1 was introduced from the H1N1pdm09 by successive reverse zoonotic events. Here, we report two novel introductions of IAV H3N2 human-origin in Chilean swine during 2023. Our study reveals a closer relationship between recent human seasonal H3N2 and novel swine strains. Interestingly, one strain maintains all the genes from the original human virus, but the other strain is already a reassortment of human H3N2 and an H1N2 previously observed on the farm. Observing global IAV sequences, a similar pattern was identified in the USA confirming the reverse zoonotic potential of current seasonal human H3N2 strains. These results highlight the importance of ongoing surveillance and reinforcing biosecurity in swine farms. These findings raise questions about their potential impact on viral dynamics in the swine population and public health, underscoring the need for further investigation into the origin and evolutionary dynamics of this emerging swine H3N2 reassortant virus.

Abstract Extracellular vesicles (EVs) are important mediators of intercellular communication in the tumour microenvironment. The cytokine transforming growth factor‐β (TGF‐β) facilitates cancer progression via EVs secreted by cancer cells, which act on recipient cells in the tumour microenvironment. However, the mechanisms of how TGF‐β affects cancer cell EV release and composition are incompletely understood. Here, we systematically investigate the effects of TGF‐β on the release and protein composition of EVs from breast cancer cells. TGF‐β suppresses the transcription of RAB27B mediated by SMAD3 and thereby hampers EV release. Using click chemistry and quantitative proteomics, we found that TGF‐β increases the quantity of protein cargo and changes the composition of EVs by downregulating RAB27B expression. The recomposed EVs, induced by TGF‐β or RAB27B depletion, inhibit CD8+ T cell‐mediated breast cancer killing. Our findings reveal the critical roles of TGF‐β and RAB27B in cancer development by regulating EV release and composition and thus provide potential targets to improve cancer immunotherapy.

Las enfermedades bacterianas son responsables de grandes pérdidas económicas en la acuicultura en todo el mundo, y las ranas son susceptibles a las bacterias Gram negativas causantes de la septicemia. Este estudio registra las características bioquímicas, moleculares y patológicas de la infección por Citrobacter freundii y Edwardsiella tarda en hembras reproductoras de rana toro (Rana catesbeiana). Para el diagnóstico bacteriológico se utilizaron reproductoras clínicamente enfermas con letargo, anorexia, piel pálida, lesiones macroscópicas de hemorragia en patas traseras, distensión abdominal y parte superior de las ancas. Se obtuvieron dos aislados bacterianos de hígado, se caracterizaron como bacilos Gram negativos, catalasa positivos y oxidasa negativos. Se realizó un ensayo experimental para confirmar los postulados de Koch. Los aislados de hígado del bioensayo (postulados de Koch), RcM1 (R. catesbeiana Muestra 1) y RcM2 (R. catesbeiana Muestra 2) fueron sometidos a identificación bioquímica mediante un API comercial 20E y molecular, utilizando la secuenciación del genoma completo. Las muestras presentaron perfil bioquímico y molecular correspondiente a C. freundii y E. tarda. Por histopatología de los organismos iniciales y del experimento presentaron severa infiltración de eritrocitos, trombocitos, formación de nódulos con aglomerados bacterianos en el centro, infiltración de fibroblastos rodeando al nódulo, manchas negras, (melanocitos) multifocal, necrosis multifocal y pérdida de la estructura original en riñón, bazo, hígado e intestino.

From December 2023 to March 2024, a surveillance program aiming to detect Highly Pathogenic Avian Influenza (HPAI) H5N1 was conducted on Antarctica territories, specifically at Fildes Peninsula (King George Island, Maritime Antarctic), and James Ross Island. At Fildes Peninsula, samples from marine birds and mammals were collected from four accessible sampling locations with significant animal colonies: Ardley Island, hosting a large concentration of Gentoo penguins (Pygoscelis papua); Ardley Cove, where small groups of likely non-breeding Chinstrap penguins (Pygoscelis antarcticus) were present; seal haul-out sites of Southern elephant (Mirounga leonina) and Weddell (Leptonycotes wedellii); and, a nesting site of Southern giant petrels (Macronectes giganteus). Additionally, six samples were collected from five dead skuas near the Lachman lakes on James Ross Island (63.7989S, 57.8105W) on March 3, 2024. Despite collecting a total of 943 samples from Fildes Peninsula, all results tested negative for HPAI, and no animals displayed clinical signs or behaviors consistent with HPAI infection. However, all skua samples from James Ross Island tested positive for HPAI H5N1 clade 2.3.4.4 by specific real-time RT-PCR reactions, confirming the first recorded HPAI-related mortality event in Antarctica (south of 60°S), specifically in skuas. Further research is necessary to genetically characterize the virus and better understand the role of skuas in viral dissemination in Antarctica.

Abstract Objective To describe the sociodemographic and clinical characteristics of imprisoned patients with epilepsy seen at Samaritana University Hospital (HUS) in Bogotá D.C., between January 2017 and November 2020. Methods Cross‐sectional cohort study of inmate patients over 18 years of age seen at HUS between January 2017 and November 2020, with a discharge diagnosis of epilepsy. A descriptive univariate analysis of patient sociodemographic and clinical characteristics was carried out. Results Overall, 92 patients were included, 95.7% were males with a median age of 32 years (IQR: 26–44); 65% were assessed in the outpatient clinic; median hospital length of stay was 2 days (IQR: 0) and 7.6% required admission to the intensive care unit; 75% had focal onset epilepsy, 63.04% with undetermined etiology 31.52% with structural causes. Polytherapy was found in 53.3%, valproic acid being the most frequently used antiseizure medication in 59.78%; lack of adherence was reported in 15.22% and inadequate seizure control in 81.52%; status epilepticus occurred in 5.34%. A total of 31 EEG recordings and 53 brain images were performed, of which, 29% and 39.62%, respectively, were abnormal. Non‐epileptic paroxysmal events were diagnosed in 5.34%, while organic or psychiatric comorbidities were found in 25%, and the use of psychoactive substances was documented in 17.39%. Upon discharge, 93.47% had no disability, and only 45.65% returned for outpatient follow‐up. Significance The clinical profile was of men in the fourth decade of life with focal onset epilepsy characterized by high seizure frequency, most of whom were receiving antiseizure medication, with a high proportion of polytherapy. The results are a point of departure for prospective studies designed to identify points to intervene and improve healthcare for inmates with epilepsy. Plain Language Summary Inmates are a vulnerable proportion of persons with epilepsy. In this group there are significant differences compared to the general population, especially with greater psychiatric comorbidity and worse control of epileptic seizures due to difficulties in accessing medical care, antiseizure medication and diagnostic tests. We found that the most characteristic population is made up of men in the fourth decade of life with a high frequency of seizures, most of whom were receiving multiple antiseizure medication This study is the first of its kind in Latin America and it is an initial approach to epilepsy in inmates.

The severity of adenovirus infection or the success of adenovirus-vectorized gene therapy largely depends on the efficiency of viral entry into cells. Various drugs can alter viral entry. This study evaluated the effects of dexamethasone, paracetamol, diclofenac, ibuprofen, and ketorolac on adenovirus entry into cells in vitro and in vivo. SiHa cell cultures pretreated with dexamethasone, paracetamol, diclofenac, ibuprofen, ketorolac, or no drug were exposed to the Ad-BGal vector. The percentage of cells showing vector entry was quantified microscopically. In vivo, BALB-C mice pretreated for 7 days with the drugs or no drug were exposed to the Ad-BGal vector intravenously (IV) or via oral (VO). Organs showing vector entry were identified by X-Gal staining and eosin counterstaining. Hepatic areas with adenovirus entry were quantified in µm2. Dexamethasone, paracetamol, and ibuprofen increased adenovirus entry both in vitro and in vivo. Diclofenac increased entry only in vitro. Ketorolac did not affect adenoviral entry. The liver exhibited the most significant changes, with dexamethasone, paracetamol, and ibuprofen increasing adenovirus entry the most. Oral administration of the vector showed that dexamethasone increased its entry into the pharynx. Some physicochemical properties of the drugs (MW (g/mol), LogP, MR [cm3/mol], tPSA, CMR, LogS, and ClogP) were analyzed, and their possible implications on cell membrane properties that could potentially influence adenovirus entry through mechanisms independent of cellular receptors were discussed. Anti-inflammatory drugs could alter adenoviral infections and adenovirus vector-based gene therapies, necessitating further research.

This study presents a single-stage and two-stage thermoelectric generator (TEG) with different geometric shapes of the legs (rectangular, trapezoidal, inverted trapezoidal, rhomboid, and hourglass shapes). The various geometric shapes of the legs are combined between the two stages using phase change material (PCM) to cool the generator. The study's objective is to determine the optimal dynamic behavior of the TEG through the geometric design of the legs. The results show the behavior of the efficiency, the generated voltage, and the time it takes for the PCM to melt. The legs of the optimal two-stage system, Rhomboid-Rhomboid (G) and Trapezoidal-Inverted Trapezoidal (B), with a relationship γT=4, reach the best efficiency of 3.88% and 3.9% for the first and second stages, respectively, applying a heat flow of Qh=0.1W. On the other hand, the single-stage rhomboid system achieves the same maximum efficiency as the two-stage rhomboid system (G system), which is 3.9%. The temperature difference of each module is almost the same as that of the single-stage system. However, the voltage generated by the two-stage TEG is higher, and the efficiency remains practically constant compared to the single-stage system, which decreases with time. The effect of PCM's phase change process on TEG performance is analyzed, considering the characteristic heat transfer of PCM.

Uropathogenic Escherichia coli (UPEC) is the main cause of urinary tract infections (UTIs) and carries virulence and resistance factors often found in mobilizable genetic elements, such as plasmids or pathogenicity islands (PAIs). UPEC is part of the extraintestinal pathogenic E. coli (ExPEC), but hybrid strains possessing both diarrheagenic E. coli (DEC) and ExPEC traits, termed “hypervirulent”, present a significant health threat. This study assessed the prevalence of UPEC PAIs, ExPEC sequence types (ST), DEC genes, carbapenemase and extended-spectrum β-lactamase (ESBL) phenotypes, resistance genotypes, and plasmids in 40 clinical isolates of UPEC. Results showed that 72.5% of isolates had PAIs, mainly PAI IV536 (53%). ESBL phenotypes were found in 65% of β-lactam-resistant isolates, with 100% of carbapenem-resistant isolates producing carbapenemase. The predominant ESBL gene was blaCTX-M-2 (60%), and the most common resistance gene in fluoroquinolone and aminoglycoside-resistant isolates was aac(6′)Ib (93%). Plasmids were present in 57% of isolates, and 70% belonged to the ST131 clonal group. Molecular markers for DEC pathotypes were detected in 20 isolates, with 60% classified as hybrid pathotypes. These findings indicate significant pathogenic potential and the presence of hybrid pathotypes in E. coli UTI clinical isolates in the Mexican population.

Background: Annona muricata L. (guanabana) leaves are rich in bioactive compounds with potential antioxidant properties. In the state of Colima, both ethanolic extracts and infusions are traditionally used in folk medicine to address various ailments. This study aimed to evaluate and compare the phytochemical composition and antioxidant activities of ethanolic extracts and infusions of A. muricata leaves from three geographic regions in Colima, Mexico, with a focus on how geographic origin affects their bioactive properties. Methods: Ethanolic extracts and infusions were prepared from A. muricata leaves and analyzed using phytochemical screening; DPPH, total antioxidant capacity (TAC), and total phenolic content (TPC) measurements; and HPLC. TLC was also conducted to examine the presence of specific compounds, such as flavonoids and phenols. Results: Both the ethanolic extracts and infusions contained significant levels of alkaloids, flavonoids, tannins, and phenolic compounds. The infusions demonstrated superior antioxidant capacity, with DPPH inhibition values of 72.5%, 68.3%, and 65.1% in the northern, central, and southern regions, respectively, compared to the ethanolic extracts’ values of 50.3%, 48.9%, and 45.0%. HPLC identified quercetin as a major compound across all samples. Geographically, the northern region exhibited higher concentrations of bioactive compounds, particularly total flavonoid content (TFC) and iron-reducing power (FRPA). Conclusions: Both the ethanolic extracts and infusions of A. muricata leaves exhibited significant antioxidant properties, with the infusions showing superior performance. The results suggest that A. muricata infusions may have potential applications in managing oxidative stress-related diseases such as cancer and diabetes. Exploring their use in traditional medicine and employing this type of approach can help discern the metabolite profile responsible for these bioactivities. Geographic factors influence the bioactive profile of the plant, and further research is needed to isolate specific bioactive compounds and elucidate their therapeutic mechanisms.

This is a retrospective case series of pediatric patients referred to the psychogenic nonepileptic events clinic (PNEE) who had comorbid diagnoses of autism spectrum disorder (ASD) or intellectual disability (ID). We describe 15 patients, nine with ASD and six with ID who had a telephone visit follow-up at 12 months. There were higher rates of male gender (40%) and comorbid epilepsy (53%) compared to the larger PNEE cohort. Eleven patients were available for follow-up and ten patients had improvement in events or were event-free. We report that patients with ASD or ID can develop PNEE and experience improvement from events.

The circular economy paradigm demands immediate and significant adjustments and changes in management and production business processes to maintain adequate to good ecosystem conditions for the use and development of human life. In this context, we analysed the impact of female leadership in the business environment and its relationship with the conservation of planetary health. This empowers women in the transition toward circular business model within the planet's capacity.For a panel data sample of the world's largest companies, we find that active female participation in high business positions leads to significant changes toward a model that protects the natural and endemic wealth of different ecosystems around de world. Additionally, we found that the active presence of women in the decision-making process concerning the protection of the environment, human development, and economic prosperity is strongly associated with the prospective knowledge that female independent directors possess, and to a greater extent, with the knowledge spillover that the presence of female executive directors entails.

Summary: Background: Surgical care holds significant importance in healthcare, especially in low and middle-income countries, as at least 50% of the 4.2 million deaths within the initial 30 days following surgery take place in these countries. The Lancet Commission on Global Surgery proposed six indicators to enhance surgical care. In Colombia, studies have been made using secondary data. However, strategies to reduce perioperative mortality have not been implemented. This study aims to describe the fourth indicator, perioperative mortality rate (POMR), with primary data in Colombia. Methods: A multicentre prospective cohort study was conducted across 54 centres (hospitals) in Colombia. Each centre selected a 7-day recruitment period between 05/2022 and 01/2023. Inclusion criteria involved patients over 18 years of age undergoing surgical procedures in operating rooms. Data quality was ensured through a verification guideline and statistical analysis using mixed-effects multilevel modelling with a case mix analysis of mortality by procedure-related, patient-related, and hospital-related conditions. Findings: 3807 patients were included with a median age of 48 (IQR 32–64), 80.3% were classified as ASA I or II, and 27% of the procedures had a low-surgical complexity. Leading procedures were Orthopedics (19.2%) and Gynaecology/Obstetrics (17.7%). According to the Clavien–Dindo scale, postoperative complications were distributed in major complications (11.7%, 10.68–12.76) and any complication (31.6%, 30.09–33.07). POMR stood at 1.9% (1.48–2.37), with elective and emergency surgery mortalities at 0.7% (0.40–1.23) and 3% (2.3–3.89) respectively. Interpretation: The POMR was higher than the ratio reported in previous national studies, even when patients had a low–risk profile and low-complexity procedures. The present research represents significant public health progress with valuable insights for national decision-makers to improve the quality of surgical care. Funding: This work was supported by Universidad del Rosario and Fundación Cardioinfantil-Instituto de Cardiología grant number CTO-057-2021, project-ID IV-FGV017.

In the present article a new design of a deformable facet and a heliostat with several deformable facets is presented. Previous work has been made around designing heliostats with concentrating facets in the facilities of the Plataforma Solar de Hermosillo. The evaluation and design process of facets and their evolution is also shown and reviewed. The facet design was initially conceived as a parabolic trough surface, however, through a modification of the facet, the surface was transformed into a concave surface. The resulting spot produced by the facet assumes nearly a spherical surface. A heliostat constructed with these facets shows similar optical performance with a previous one made with spherical facets; this spherical heliostat has a higher peak and mean flux. Nevertheless, the deformable facet heliostat presents a simpler construction and structure. A comparison between both heliostats will be presented.

La enfermedad cardiovascular es la principal causa de mortalidad en México y en el mundo; la dislipidemia constituye uno de los principales factores de riesgo. Pese a la importancia de su impacto epidemiológico, entre los médicos de primer contacto aún existe la necesidad de incrementar el conocimiento en los conceptos básicos para su diagnóstico, así como en las recomendaciones más recientes en el tratamiento de esta patología. El presente documento, elaborado por expertos en el tema, se desarrolló a partir de 10 preguntas, las cuales dieron origen a 22 recomendaciones seleccionadas mediante metodología Delphi. Entre las recomendaciones se incluye la medición del perfil de lípidos a partir de los 20 años de edad, las metas de tratamiento para pacientes de acuerdo con su riesgo cardiovascular, el seguimiento de pacientes con dislipidemia y la prevención primaria y secundaria.

Este artículo indaga elementos clave de una experiencia histórica, la toma de Marquetalia entre los años 1960-1964 por parte del Ejército Nacional y la posterior confrontación que en esta zona se dio entre la guerrilla de las FARC y las autodefensas indígenas por más de tres décadas (1964-1996). Este evento fue crítico en el desarrollo del conflicto armado en Colombia por ser un hito en el desarrollo de la guerra de guerrillas y por la forma en que el Estado se hizo al control de regiones marginales. El escrito se centra en el proceso de dominio y coerción que desató el Estado sobre el pueblo indígena Nasa Wesx del sur de Tolima en el desarrollo de su estrategia militar de control territorial. La investigación está centrada en un trabajo de campo etnográfico producto de diálogos informales con los habitantes de la zona. El enfoque de la investigación es cualitativo, centrado en la interpretación de las narraciones de personas que vivieron estos episodios. Se interesa por las relaciones y tensiones entre Estado y grupos indígenas, priorizando un enfoque étnico para comprender los alcances culturales y territoriales de esta confrontación. El trabajo identifica y visibiliza el punto de vista de poblaciones étnicas que han hecho parte del conflicto, ya sea como víctimas, actores armados o sujetos de autonomía política y territorial. El texto concluye con una discusión sobre la forma en que operan los márgenes como áreas donde el Estado constituye sus dinámicas de control y poder.

La salinidad es un problema en zonas agrícolas al comprometer el crecimiento de los cultivos. Las variedades modernas de chile se adaptan poco a esta condición; por lo que la búsqueda de variabilidad en plantas de chile silvestre ayudaría para crear variedades mejoradas. El objetivo fue determinar los efectos de la salinidad y la distribución de la variación fenotípica entre poblaciones, entre y dentro de familias, y estimar la proporción de esta variación fenotípica que tiene una base genética. Se probaron tres tratamientos (0, 25 y 50 mM NaCl) en seis poblaciones de chile silvestre del Noroeste de México. Se observaron diferencias significativas entre tratamientos para todos los caracteres. La salinidad redujo todos los rasgos con excepción de grosor de hoja; fue mayor con 50 mM, siendo la materia seca de raíz (45.2%), hojas (38.7%), área foliar (37.6%), biomasa total (33.7%) los rasgos más sensibles. La mayor variación fenotípica se distribuyó dentro de familias. El mayor coeficiente de variación fue en peso seco de raíz (40%). Las poblaciones mantuvieron variación en todos los rasgos excepto en altura de planta; Presa Oviachic fue superior en peso seco de planta, raíz, tallo y hojas, área foliar, número de hojas y diámetro de tallo; Mazocahui en grosor de hoja; Lo de Vega y Yecorato en lecturas SPAD. Los niveles de NaCl influyeron en la expresión fenotípica de los rasgos estudiados. La variabilidad detectada en las poblaciones resulta promisoria para iniciar un proceso de domesticación en chile silvestre.

Enhancers are stretches of regulatory DNA that bind transcription factors (TFs) and regulate the expression of a target gene. Shadow enhancers are two or more enhancers that regulate the same target gene in space and time and are associated with most animal developmental genes. These multi-enhancer systems can drive more consistent transcription than single enhancer systems. Nevertheless, it remains unclear why shadow enhancer TF binding sites are distributed across multiple enhancers rather than within a single large enhancer. Here, we use a computational approach to study systems with varying numbers of TF binding sites and enhancers. We employ chemical reaction networks with stochastic dynamics to determine the trends in transcriptional noise and fidelity, two key performance objectives of enhancers. This reveals that while additive shadow enhancers do not differ in noise and fidelity from their single enhancer counterparts, sub- and superadditive shadow enhancers have noise and fidelity trade-offs not available to single enhancers. We also use our computational approach to compare the duplication and splitting of a single enhancer as mechanisms for the generation of shadow enhancers and find that the duplication of enhancers can decrease noise and increase fidelity, although at the metabolic cost of increased RNA production. A saturation mechanism for enhancer interactions similarly improves on both of these metrics. Taken together, this work highlights that shadow enhancer systems may exist for several reasons: genetic drift or the tuning of key functions of enhancers, including transcription fidelity, noise and output.