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Aquí se describen distintos tipos de opciones de rescate anticipado que incluyen bonos de empresas. También se presenta un modelo de valoración de bonos con rescate anticipado cuando las tasas de interés siguen un proceso estocástico, inspirado en el modelo de valoración de opciones americanas desarrollado por Longstaff y Schwartz (2001), conocido como algoritmo Least Squares Montecarlo. La metodología propuesta se aplica a la valoración de dos bonos con rescate anticipado del tipo semiamericano, sobre la base de los cuales se desarrolla un análisis de sensibilidad para el valor del bono y para el valor de la opción de rescate.

Background: Among voice restoration options following laryngectomy, tracheoesophageal puncture (TEP) appears to be the most common. Currently, there is no consensus that exists with regard to the timing of performing TEP and the decision to perform a primary or secondary TEP has mostly been based on physician preference and expert opinion rather than data. Objective of Review: The objective of this study was to compare primary and secondary tracheoesophageal puncture (TEP) for voice rehabilitation in laryngectomy patients in terms of success and complication rates. Type of Review: A systematic review of studies in the English literature was conducted for studies that directly compared primary and secondary TEP. Search Strategy: A comprehensive search of MEDLINE (January 1948‐15 July 2016), EMBASE (January 1974‐15 July 2016) and Web of Science (January 1970‐15 July 2016) was performed. Evaluation Method: Two authors (KL/BAC) independently reviewed titles and abstracts, read full‐text papers, extracted data and assessed quality. Disagreements were resolved via consensus. A third author (DV) resolved disagreements between reviewers when consensus was not possible. Results: Eleven retrospective clinical cohort studies were included. No randomised controlled trials were identified. Newcastle‐Ottawa score for assessment of quality ranged from 5 to 7. Success rate was defined differently across most studies. Two studies found higher success with primary TEP compared to secondary TEP; nine studies found no difference. Voice outcomes were inconsistently measured; no difference between groups was found in 4 studies. Complication rates were divided into TEP site related, infectious and stenosis. No difference between primary and secondary TEP was found in all but one study which showed a higher rate of pharyngocutaneous fistula in the primary TEP group in salvage laryngectomy patients. Conclusions: There is no robust evidence to suggest that primary TEP is associated with poorer outcomes compared to secondary TEP. A well‐designed randomised controlled trial is required to appropriately answer this question. [ABSTRACT FROM AUTHOR]

The pygmy raccoon Procyon pygmaeus and dwarf coati Nasua nelsoni, both endemic to Cozumel Island, Mexico, are two of the most endangered carnivores in the world, and their persistence requires active management. However, the taxonomic status of these populations remains unclear. Therefore we investigated mitochondrial DNA variation using the control region to examine the genetic uniqueness and evolutionary history of these taxa. Using strict phylogenetic criteria, species-level uniqueness of the Cozumel taxa was difficult to discern based solely on haplotype groupings and identification of unique alleles. However, population genetic approaches indicate significant population differentiation between Cozumel and mainland populations and we suggest that these taxa should be treated as distinct management units from their mainland conspecifics. Coalescent analysis indicated that the pygmy raccoon diverged from the mainland about 3050–200 111 years before present (ybp) and the Cozumel coati 1263–82 896 ybp; dates that can be further constrained by incorporating known-age subfossil specimens from Cozumel as well as the geological history of the island. Thus, although it is likely that the island taxa colonized Cozumel before the Mayan peoples populated the island, we are unable to definitively reject the hypothesis that colonization by these taxa was not human facilitated. [ABSTRACT FROM AUTHOR]

Studies the function of the Galphao protein for muscarinic regulation of Ca2+ channels in mouse heart. Neuronal function in Galphao -/- mice; Cardiac function in Galphao -/- mice; Histologic abnormalities in the nervous system; Response of the L-type calcium channel to isoproterenol; Muscarinic regulation of atrial K+ channels.

Presents research characterizing the prominent unidentified proteins of the growth cone membrane and an examination of the interactions among its constituents. Go is a major growth cone component; GAP-43 stimulates GTP-gamma-S binding to Go; GA-43 decapeptide interacts with Go; Discussion.

Once developed, end-stage renal disease cannot be reversed by any current therapy. Bone morphogenetic protein-7 (BMP-7), however, is a possible treatment for reversing end-stage renal disease. Previously, we showed that the BMP antagonist uterine sensitization-associated gene-1 (USAG-1, also known as ectodin and sclerostin domain-containing 1) negatively regulates the renoprotective action of BMP-7. Here, we show that the ratio between USAG-1 and BMP-7 expression increased dramatically in the later stage of kidney development, with USAG-1 expression overlapping BMP-7 only in differentiated distal tubules. Examination of USAG-1 expression in developing kidney indicated that a mosaic of proximal and distal tubule marker-positive cells reside side by side in the immature nephron. This suggests that each cell controls its own fate for becoming a proximal or distal tubule cell. In kidney injury models, the ratio of USAG-1 to BMP-7 expression decreased with kidney damage but increased after subsequent kidney regeneration. Our study suggests that USAG-1 expression in a kidney biopsy could be useful in predicting outcome.Kidney International (2008) 73, 181–191; doi:10.1038/sj.ki.5002626; published online 17 October 2007 [ABSTRACT FROM AUTHOR]

Background: The SCI-GDI is an accurate and effective metric to summarize gait kinematics in adults with SCI. It is usually computed with the information registered with a photogrammetry system because it requires accurate information of pelvic and hip movement in the three anatomic planes, which is hard to record with simpler systems. Additionally, due to being developed from the GDI, the SCI-GDI is built upon nine joint movements selected for a pediatric population with cerebral palsy, for which the GDI was originally developed, but those nine movements are not necessarily as meaningful for adults with SCI. Nevertheless, pelvic movement and hip rotation have been proven to have low reliability even when acquired with gold-standard photogrammetry systems. Additionally, the use of photogrammetry is limited in real-life scenarios and when used with rehabilitation technologies, which limits the use of the SCI-GDI to evaluate gait in alternative scenarios to gait laboratories and to evaluate technologies for gait assistance. This research aimed to improve the SCI-GDI to broaden its applicability beyond the use of photogrammetry., Methods: An exploration of the mathematical relevance of each joint movement included in the original GDI for the performance of the metric is performed. Considering the results obtained and the clinical relevance of each of the 9 joints used to compute the SCI-GDI in the gait pattern of the SCI population, a more adaptable SCI-GDI is proposed using four joint movements that can be precisely captured with simpler systems than photogrammetry: sagittal planes of hip, knee and ankle and hip abduction/adduction., Results: The reduced SCI-GDI (rSCI-GDI) effectively represents gait variability of adults with SCI as does the SCI-GDI, while providing more generalizable results and equivalent or stronger correlations with clinical tests validated in the population. During the derivation of the improved index, it was demonstrated that pelvic movements, hip rotation, and foot progression angle introduce high variability to the dataset of gait patterns of the adult population with SCI, but they have low relevance to characterize gait kinematics of this population. The rSCI-GDI can be calculated using the 14-feature vectorial basis included in the electronic addendum provided., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Herrera-Valenzuela, Sinovas-Alonso, Reyes, Gil-Agudo and del-Ama.)

Background: To overcome the application limitations of functional electrical stimulation (FES), such as fatigue or nonlinear muscle response, the combination of neuroprosthetic systems with robotic devices has been evaluated, resulting in hybrid systems that have promising potential. However, current technology shows a lack of flexibility to adapt to the needs of any application, context or individual. The main objective of this study is the development of a new modular neuroprosthetic system suitable for hybrid FES-robot applications to meet these needs., Methods: In this study, we conducted an analysis of the requirements for developing hybrid FES-robot systems and reviewed existing literature on similar systems. Building upon these insights, we developed a novel modular neuroprosthetic system tailored for hybrid applications. The system was specifically adapted for gait assistance, and a technological personalization process based on clinical criteria was devised. This process was used to generate different system configurations adjusted to four individuals with spinal cord injury or stroke. The effect of each system configuration on gait kinematic metrics was analyzed by using repeated measures ANOVA or Friedman's test., Results: A modular NP system has been developed that is distinguished by its flexibility, scalability and personalization capabilities. With excellent connection characteristics, it can be effectively integrated with robotic devices. Its 3D design facilitates fitting both as a stand-alone system and in combination with other robotic devices. In addition, it meets rigorous requirements for safe use by incorporating appropriate safety protocols, and features appropriate battery autonomy, weight and dimensions. Different technological configurations adapted to the needs of each patient were obtained, which demonstrated an impact on the kinematic gait pattern comparable to that of other devices reported in the literature., Conclusions: The system met the identified technical requirements, showcasing advancements compared to systems reported in the literature. In addition, it demonstrated its versatility and capacity to be combined with robotic devices forming hybrids, adapting well to the gait application. Moreover, the personalization procedure proved to be useful in obtaining various system configurations tailored to the diverse needs of individuals., (© 2024. The Author(s).)

When assessing gait analysis outcomes for clinical use, it is indispensable to use an accurate system ensuring a minimal measurement error. Inertial Measurement Units (IMUs) are a versatile motion capture system to evaluate gait kinematics during out-of-lab activities and technology-assisted rehabilitation therapies. However, IMUs are susceptible to distortions, offset and drifting. Therefore, it is important to have a validated instrumentation and recording protocol to ensure the reliability of the measurements, to differentiate therapy effects from system-induced errors. A protocol was carried out to validate the accuracy of gait kinematic assessment with IMUs based on the similarity of the waveform of concurrent signals captured by this system and by a photogrammetry reference system. A gait database of 32 healthy subjects was registered synchronously with both devices. The validation process involved two steps: 1) a preliminary similarity assessment using the Pearson correlation coefficient, and 2) a similarity assessment in terms of correlation, displacement and gain by estimating the offset between signals, the difference between the registered range of motion (∆ROM), the root mean square error (RMSE) and the interprotocol coefficient of multiple correlation (CMC P ). Besides, the CMC P was recomputed after removing the offset between signals (CMC Poff ). The correlation was strong (r > 0.75) for both limbs for hip flexion/extension, hip adduction/abduction, knee flexion/extension and ankle dorsal/plantar flexion. These joint movements were studied in the second part of the analysis. The ∆ROM values obtained were smaller than 6°, being negligible relative to the minimally clinically important difference (MCID) estimated for unaffected limbs, and the RMSE values were under 10°. The offset for hips and ankles in the sagittal plane reached -9° and -8°, respectively, whereas hips adduction/abduction and knees flexion/extension were around 1°. According to the CMC P , the kinematic pattern of hip flexion/extension (CMC P > 0.90) and adduction/abduction (CMC P > 0.75), knee flexion/extension (CMC P > 0.95) and ankle dorsi/plantar flexion (CMC P > 0.90) were equivalent when captured by each system synchronously. However, after offset correction, only hip flexion/extension (CMC Poff = 1), hip adduction/abduction (CMC Poff > 0.85) and knee flexion/extension (CMC Poff > 0.95) satisfied the conditions to be considered similar., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Blanco-Coloma, García-González, Sinovas-Alonso, Torio-Álvarez, Martos-Hernández, González-Expósito, Gil-Agudo and Herrera-Valenzuela.)

In the present work, short glass fiber is superficially modified with different concentrations of polyhedral oligomeric silsesquioxanes (Trisilanol-Isobutyl, TSI-POSS) for processing as a filler in a polypropylene matrix (PP). It is observed that increasing the amount of TSI-POSS increases the fracture point and tensile strength; the opposite is the case for the strength impact property. The behaviors of both dynamic mechanical and thermal analyses are also observed. The flame behavior, i.e., the burning rate, decreases with increasing TSI-POSS in the polymers.

Objective: This study aimed to estimate amyotrophic lateral sclerosis (ALS) incidence and survival rates in the Metropolitan region of Chile., Methods: We conducted a cohort study of ALS cases in the Metropolitan Region from 2016 to 2019. A total of 219 ALS patients were recruited from Corporación ELA-Chile registry, in collaboration with neurologists from Sociedad de Neurología, Psiquiatría y Neurocirugía de Chile. We calculated incidence rates by sex and age and determined median survival from onset and diagnosis. Survival analysis used the Kaplan-Meier statistic, estimating hazard ratios for age, sex, time from symptom onset and from diagnosis using a Weibull regression model. All analyses were done using R 4.1.0., Results: Overall, ALS diagnosis incidence was 0.97 cases per 100,000 inhabitants, peaking in the 70-79 age group and declining thereafter. The male-to-female ratio was 1.23. The median time to death from diagnosis was 2.3 years (95% confidence interval [CI]: 1.9-2.5), and from the first symptom, it was 3.1 years (95% CI: 2.8-3.5)., Conclusions: This is the first population-based study reporting ALS incidence and survival rates in Chile's Metropolitan region. Incidence resembled other Latin American studies. Median survival from diagnosis and from the first symptom were in line with previous findings. Our results corroborated lower ALS rates in Latin America, consistent with prior research.

Introduction: The consumption of alcohol, tobacco, and cannabis is a public health problem that impacts the cognitive, social, and emotional development of adolescents. Prevention strategies such as the "Unplugged" program are effective in delaying the progression of daily smoking and episodes of drunkenness among adolescents. "Yo Se Lo Que Quiero" (YSLQQ) corresponds to the adaptation of this program to the Chilean context. This study assesses the acceptability and feasibility of implementing this program to the local reality., Material and Methods: This was a cluster-randomized controlled pilot study conducted on six public schools. All consented students attending 6th, 7th, and 8th grades (n = 1,180) participated in the study. The schools were randomly assigned to one of two conditions in a 1:1 ratio: (1) the "YSLQQ" intervention group (n = 526), and (2) the Control group (n = 654). The program consisted of a 12-hour class-based curriculum based on a comprehensive social-influence approach delivered by a trained facilitator. The acceptability and feasibility were assessed in the intervention group at the end of the intervention using questionnaires answered by students and facilitators. The quality and fidelity of the program were evaluated during the implementation using self-ported surveys answered by the facilitators and the assessment of video-recorded sessions rated by external observers. Finally, a pre-test and a post-test survey assessing past and current substance use and risk and protective factors were conducted before and immediately after the program's implementation., Results: A high proportion of students (49.6%) liked the sessions. 79.2% reported that the YSLQQ helped them learn about the dangers of substances, while 65.8% reported having more skills to avoid substance use in the future. Regarding students' satisfaction with YSLQQ, 62.9% reported being happy or very happy with the program. Facilitators reported implementing the intervention according to the manual in 73.9% of sessions. Regarding substance use, students who participated in the intervention groups reported a significant reduction in drunkenness in the last year and last 30-day prevalence and also a significant reduction in a lifetime and 30-day prevalence of cannabis use when compared with those students in the control group., Conclusions: Our results suggest that YSLQQ has adequate acceptability and feasibility to be implemented in the Chilean context, and there were promising results in reducing drunkenness and cannabis use. Future research should confirm these results in a larger RCT study., Trial Registration: The trial was registered in ClinicalTrials.gov, NCT04566627; registration date: 01/03/2019., (© 2024. The Author(s).)

The Amazon region is home to many plant species, many of which have not been studied. The objective was to evaluate the physicochemical properties, bioactive compounds, and antioxidant activity of Phytelephas tenuicalis (tintiuk), Grias neuberthii (apai), Euterpe oleracea (acai), and Mauritia flexuosa (brown moriche). Physicochemical analyses were carried out on fresh fruit from local markets. Bioactive compounds (carotenoids, phenolics, vitamin C, and organic acids) were quantified in the freeze-dried pulp by rapid-resolution liquid chromatography (RRLC), and antioxidant activity was determined by ABTS and DPPH assays. The results showed high soluble solids (10.7 °Brix) and ascorbic acid (67.3 mg/100 g DW) in tintiuk; β-carotene (63.4 mg/100 g DW) and malic acid (19.6 g/100 g DW) in brown moriche; quercetin (944.2 mg/100 g DW) and antioxidant activity by ABTS (6.7 mmol ET/100 g DW) in apai; and citric acid (2.1 g/100 g DW) in acai. These results indicate interesting bioactive properties that could increase the consumption of these fruits nationally and internationally, benefiting local farmers and stimulating the development of new products in functional food, medicine, and cosmetics.

Urban evolutionary ecology is inherently interdisciplinary. Moreover, it is a field with global significance. However, bringing researchers and resources together across fields and countries is challenging. Therefore, an online collaborative research hub, where common methods and best practices are shared among scientists from diverse geographic, ethnic, and career backgrounds would make research focused on urban evolutionary ecology more inclusive. Here, we describe a freely available online research hub for toolkits that facilitate global research in urban evolutionary ecology. We provide rationales and descriptions of toolkits for: (1) decolonizing urban evolutionary ecology; (2) identifying and fostering international collaborative partnerships; (3) common methods and freely-available datasets for trait mapping across cities; (4) common methods and freely-available datasets for cross-city evolutionary ecology experiments; and (5) best practices and freely available resources for public outreach and communication of research findings in urban evolutionary ecology. We outline how the toolkits can be accessed, archived, and modified over time in order to sustain long-term global research that will advance our understanding of urban evolutionary ecology., Competing Interests: The authors of this article do not have any conflicts of interest to report with respect to this manuscript., (© 2024 The Author(s). Ecology and Evolution published by John Wiley & Sons Ltd.)

The Jambato Harlequin toad ( Atelopus ignescens ), a formerly abundant species in the Andes of Ecuador, faced a dramatic population decline in the 1980s, with its last recorded sighting in 1988. The species was considered Extinct by the IUCN until 2016, when a fortuitous discovery of one Jambato by a local boy reignited hope. In this study, we present findings from an investigation conducted in the Angamarca parish, focusing on distribution, abundance, habitat preferences, ecology, disease susceptibility, and dietary habits of the species. In one year we identified 71 individuals at different stages of development in various habitats, with a significant presence in agricultural mosaic areas and locations near water sources used for crop irrigation, demonstrating the persistence of the species in a complex landscape, with considerable human intervention. The dietary analysis based on fecal samples indicated a diverse prey selection, primarily comprising arthropods such as Acari, Coleoptera, and ants. Amphibian declines have been associated with diseases and climate change; notably, our study confirmed the presence of the pathogen Batrachochytrium dendrobatidis ( Bd ), but, surprisingly, none of the infected Jambatos displayed visible signs of illness. When analyzing climatic patterns, we found that there are climatic differences between historical localities and Angamarca; the temporal analysis also exposes a generalized warming trend. Finally, in collaboration with the local community, we developed a series of management recommendations for terrestrial and aquatic environments occupied by the Jambato., Competing Interests: The authors declare there are no competing interests., (©2024 Vega-Yánez et al.)

Introduction: Congenital Heart Disease (CHD) is the most common congenital disorder and a leading cause of infant mortality. Despite improved survival rates, patients with CHD often face malnutrition due to increased metabolic demands, feeding difficulties, and gastrointestinal dysfunction. Malnutrition in CHD is linked to poor short and long-term clinical outcomes. Gastrostomy (GT) is frequently used for long-term enteral support, and laparoscopic GT (LGT) has demonstrated advantages in children without CHD. This study evaluated a modified Georgeson's percutaneous LGT technique and its perioperative complications in children with CHD., Methods: We performed an analytical retrospective cohort study from 2018 to 2022, including patients younger than 24 months with a diagnosis of CHD who underwent LGT. The primary outcome evaluated was the presence of complications during surgery and the first thirty postoperative days. Complications were graded using Clavien-Dindo's (CD) classification. Sociodemographic, clinical, and procedure-related variables were collected. A bivariate analysis was performed using STATA 15, and a p  < 0.05 was considered statistically significant., Results: Seventy-eight patients were eligible (male 56.41%, Median age 129.5 days, weight: 4.83 kg). The median surgery time was 35 min. The complication rate was 24.36%. The most frequent complications were GT site infection (10.26%), followed by leakage (8.97%) and granuloma formation (6.41%). Conversion to open surgery was significantly associated with postoperative complications ( p  = 0.002)., Conclusion: This modified technique is well-tolerated in children with CHD, demonstrating a low rate of CD grade 3A/3B complications and no grade 4 or 5 complications., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Chaparro-Zaraza, Pinilla-Orejarena, Otoya-Castrillón, Chacón-Valenzuela, Quintero-Olarte, Cifuentes-Rincón, Quesada-Uribe, Durán-Hernandez, Bermon and Manrique-Hernandez.)

Understanding the processes that drive phenotypic diversification and underpin speciation is key to elucidating how biodiversity has evolved. Although these processes have been studied across a wide array of clades, adaptive radiations (ARs), which are systems with multiple closely related species and broad phenotypic diversity, have been particularly fruitful for teasing apart the factors that drive and constrain diversification. As such, ARs have become popular candidate study systems for determining the extent to which ecological features, including aspects of organisms and the environment, and inter- and intraspecific interactions, led to evolutionary diversification. Despite substantial past empirical and theoretical work, understanding mechanistically how ARs evolve remains a major challenge. Here, we highlight a number of understudied components of the environment and of lineages themselves, which may help further our understanding of speciation and AR. We also outline some substantial remaining challenges to achieving a detailed understanding of adaptation, speciation, and the role of ecology in these processes. These major challenges include identifying factors that have a causative impact in promoting or constraining ARs, gaining a more holistic understanding of features of organisms and their environment that interact resulting in adaptation and speciation, and understanding whether the role of these organismal and environmental features varies throughout the radiation process. We conclude by providing perspectives on how future investigations into the AR process can overcome these challenges, allowing us to glean mechanistic insights into adaptation and speciation., (Copyright © 2024 Cold Spring Harbor Laboratory Press; all rights reserved.)