Distribución, preferencias de forrajeo y despersión de semillas por aves frugívoras en estados sucesionales de bosque tropical seco en la cuenca del Balsas de Guerrero

Changes in land use have modified the interactions between frugivorous birds and plants, as well as the processes of seed dispersal. Today, many Mesoamerican tropical dry forests have been reduced to small patches in different stages of succession. This is the main reason why it is necessary to conduct further analysis on the community dynamics in these environments. The present study was focused on the changes in the structure of plant communities and their influence on the distribution of foraging preferences and seed dispersal of frugivorous birds in three successional stages (early, intermediate and mature) in a tropical dry forest. The results showed that the presence of frugivorous birds increased in intermediate and mature stages due to the increased complexity of the vegetation, and the abundance of Bursera drupes that are consumed by frugivore birds during the dry season. Migratory frugivorous birds are present in all stages of succession, but are more common in early stages. The fruit removal by these species and consequent dispersion contributes to the recovery of vegetation in these sites. The results of the foraging preferences confirmed the relationship between frugivorous birds and species of Bursera. Generally Bursera fruits and particularly those of B. longipes are widely consumed during the dry season and the legitimal dispersers are birds who frequently use this resource. Furthermore, frugivorous various with relatively large size and strong bills were associated with plants that produce large and small fruits with hard seeds. In the early stages only Myiarchus cinerascens had an important contribution to the seed dispersal of B. longipes. In the in the intermediate stages M. nuttingi, M. tyrannulus, M. cinerascens and Melanerpes chrysogenis were the moste efficient dispersers and these four, together with Myiodynastes luteiventris where the most efficient seed dispersers in mature forests. Further research on the time of establishment of individuals of this and other plant species until they are reproductive adults is needed to better understand the population dynamics of plants and their interaction with frugivorous birds in tropical dry forests.El cambio del uso del suelo ha afectado las interacciones entre las aves frugívoras y las plantas, así como los procesos de dispersión de semillas. En la actualidad, grandes extensiones de bosques tropicales secos de Mesoamérica se han reducido a pequeños parches en distintos estados de sucesión. Es por esto que analizar la dinámica de las comunidades en estos ambientes constituye un campo de investigación de interés en ecología y conservación. Este estudio se centró en evaluar los cambios en la estructura de las comunidades de plantas y su influencia en la distribución, las preferencias de forrajeo y la dispersión de semillas de aves frugívoras en tres estados de sucesión (temprano, intermedio y maduro) en un bosque tropical seco. Los resultados mostraron que la presencia de aves frugívoras aumenta en etapas intermedias y maduras, producto de la mayor complejidad de la vegetación, y por la presencia de árboles de Bursera, que durante la estación seca del año presentan gran disponibilidad de frutos maduros. Las aves frugívoras migratorias están presentes en todas las etapas de sucesión, aunque son más frecuentes en etapas tempranas. La remoción de frutos y consecuente dispersión por estas especies contribuye a la recuperación de la vegetación en estos sitios. Los resultados de las preferencias de forrajeo confirmaron la relación entre las aves frugívoras y las especies de Bursera. En general los frutos de Bursera y muy particularmente los de B. longipes se consumen en abundancia en la época seca, y las aves dispersoras legítimas son las que usan más frecuentemente este recurso. Por otro lado, varios frugívoros de tamaño relativamente grandes y de picos fuertes se asociaron con plantas zoócoras con frutos grandes y pequeños con semillas duras. Del total de aves frugívoras, en las etapas tempranas solo Myiarchus cinerascens tuvo una contribución importante a la dispersión de semillas de B. longipes. En las intermedias, M. nuttingi, M. tyrannulus, M. cinerascens y Melanerpes chrysogenys fueron los dispersores más efectivos. En las estapas maduras Myiodynastes luteiventris también fue un dispersor legítimo eficiente, además de las anteriores. Es neceario realizar más estudios que analicen el tiempo de establecimiento de los individuos de esta y otras especies de plantas hasta que sean adultos reproductivos para comprender mejor la dinámica demográfica de las plantas y su interacción con las aves frugívoras

Three-dimensional cardiac fibre disorganization as a novel parameter for ventricular arrhythmia stratification after myocardial infarction

Aims: Myocardial infarction (MI) alters cardiac fibre organization with unknown consequences on ventricular arrhythmia. We used diffusion tensor imaging (DTI) of three-dimensional (3D) cardiac fibres and scar reconstructions to identify the main parameters associated with ventricular arrhythmia inducibility and ventricular tachycardia (VT) features after MI. Methods and results: Twelve pigs with established MI and three controls underwent invasive electrophysiological characterization of ventricular arrhythmia inducibility and VT features. Animal-specific 3D scar and myocardial fibre distribution were obtained from ex vivo high-resolution contrast-enhanced T1 mapping and DTI sequences. Diffusion tensor imaging-derived parameters significantly different between healthy and scarring myocardium, scar volumes, and left ventricular ejection fraction (LVEF) were included for arrhythmia risk stratification and correlation analyses with VT features. Ventricular fibrillation (VF) was the only inducible arrhythmia in 4 out of 12 infarcted pigs and all controls. Ventricular tachycardia was also inducible in the remaining eight pigs during programmed ventricular stimulation. A DTI-based 3D fibre disorganization index (FDI) showed higher disorganization within dense scar regions of VF-only inducible pigs compared with VT inducible animals (FDI: 0.36; 0.36-0.37 vs. 0.32; 0.26-0.33, respectively, P = 0.0485). Ventricular fibrillation induction required lower programmed stimulation aggressiveness in VF-only inducible pigs than VT inducible and control animals. Neither LVEF nor scar volumes differentiated between VF and VT inducible animals. Re-entrant VT circuits were localized within areas of highly disorganized fibres. Moreover, the FDI within heterogeneous scar regions was associated with the median VT cycle length per animal (R2 = 0.5320). Conclusion: The amount of scar-related cardiac fibre disorganization in DTI sequences is a promising approach for ventricular arrhythmia stratification after MI.The CNIC (Madrid, Spain) is supported by the Ministry of Science, Innovation and Universities and the Pro CNIC Foundation. The CNIC and the BSC (Barcelona, Spain) are Severo Ochoa Centers of Excellence (SEV-2015-0505 and SEV-2011-0067, respectively). This study was supported by grants from Instituto de Salud Carlos III, Fondo Europeo de Desarrollo Regional (RD12/0042/0036, CB16/11/00458), Spanish Ministry of Science, Innovation and Universities (SAF2016-80324-R, PI16/02110, and DTS17/00136), and by the European Commission [ERA-CVD Joint Call (JTC2016/APCIN-ISCIII-2016), grant#AC16/00021]. The study was also partially supported by the Fundacion Interhospitalaria para la Investigacion Cardiovascular (FIC, Madrid, Spain), the Spanish Society of Cardiology (Dr. Pedro Zarco award) and the Heart Rhythm section of the Spanish Society of Cardiology (DFR). J.J. is supported by R01 Grant HL122352 from the National Heart Lung and Blood Institute, USA National Institutes of Health. J.A.S. is funded by the CompBioMed project, H2020-EU.1.4.1.3 European Union's Horizon 2020 research and innovation programme, grant#675451. D.G.L. has received financial support through the 'la Caixa' Fellowship Grant for Doctoral Studies, 'la Caixa' Banking Foundation, Barcelona, Spain.S

Blackpoll warbler (Dendroica striata) and other records of birds from Guerrero, Mexico

We present a list of noteworthy distributional records for 12 species of birds in the Mexican state of Guerrero. One (Dendroica striata) is new for the state, and the remaining either significantly expand their known geographic and seasonal distribution or add information about their presence in the state

Understanding Voters' Preference for Candidates in the Philippine Presidential Elections

<p>Philippine presidential elections have traditionally been characterized by the dominance of political popularity, populism, and financial interests, often marred by incidents of violence and electoral fraud. In this context, higher education is recognized as a pivotal tool for mitigating voter naivety and fostering informed political engagement. This study seeks to assess the preferences of voters, specifically 108 students from BiPSU (the research population), and to identify the significant sources of information that influence their decision-making about the election.</p&gt

Supplementary Material for: Multifocal Insulinoma as the Unique Presenting Feature of MEN1 in an Adolescent

Introduction Multiple Endocrine Neoplasia Type 1 (MEN1) is an autosomal dominant inherited disorder defined by the presence of two of the following endocrinopathies: primary hyperparathyroidism, anterior pituitary tumors, and duodenopancreatic neuroendocrine tumors (NETs). NETs, which can secrete hormones including insulin, gastrin, and glucagon, among others, are common in patients with MEN1 and are a major cause of morbidity and premature death. NETs are more common later in life, with very few cases described in children. Here, we describe a unique case of an adolescent with multifocal pancreatic NETs as the single presenting feature of MEN1. Case Presentation A 13-year-old healthy male presented with severe weakness, altered mental status, and syncope in the setting of a venous blood glucose (BG) of 36 mg/dL. Workup showed an elevated insulin level (14 mcIU/mL) when BG was 39 mg/dL with positive response to glucagon, concerning for hyperinsulinism. Diazoxide and chlorothiazide were started but not well tolerated secondary to emesis. Three suspected NETs were identified by MRI and 68-Ga DOTATATE PET-CT imaging, including the largest, a 2.1 cm mass in the pancreatic head. A fourth mass in the pancreatic tail was identified via intraoperative ultrasound. All lesions were successfully enucleated and excised, and glucose levels normalized off diazoxide by post-op day 2. While the primary lesion stained for insulin and somatostatin by immunofluorescence (IF), consistent with his clinical presentation, the additional tumors expressed glucagon, somatostatin, pancreatic polypeptide, and chromogranin A but were negative for insulin. Genetic testing confirmed a pathogenic heterozygous mutation in MEN1 (c.969C>A, p.Tyr323). He had no other signs of MEN-associated comorbidities on screening. Discussion/Conclusion This case demonstrates that young patients with MEN1 can present with multifocal NETs. These NETs may have polyhormonal expression patterns despite a clinical presentation consistent with one primary hormone. Our patient had clinical symptoms and laboratory evaluation consistent with an insulinoma but was found to have four NETs, each with different IF staining patterns. Advanced pre-operative and intraoperative imaging is important to identify and treat all present NETs. Moreover, serum hormone levels pre- and post-treatment could help evaluate whether NETs are actively secreting hormones into the bloodstream or simply expressing them within the pancreas. Finally, this case highlights the importance of genetic testing for MEN1 in all young patients with insulinomas