Search

Abies guatemalensis Rehder, an endangered conifer endemic to Central American highlands, is ecologically vital in upper montane forests. It faces threats from habitat fragmentation, unsustainable logging, and illegal Christmas tree harvesting. While previous genetic studies on mature trees from eighteen populations showed high within-population diversity and limited among-population differentiation, the genetic impact of recent anthropogenic pressures on younger generations has yet to be discovered. Understanding these effects is crucial for developing effective conservation strategies for this vulnerable species. We sampled 170 young trees (< 15 years old) from seven populations across Guatemala. Seven microsatellite markers were used to analyse genetic diversity, population structure, and recent demographic history. Moderate levels of genetic diversity were observed within populations (mean Shannon diversity index = 4.97, mean Simpson’s index = 0.51, mean allelic richness = 11.59, mean observed heterozygosity = 0.59). Although genetic structure broadly aligned with mountain corridors, substantial admixture patterns suggest historical connectivity across all populations. Most populations showed evidence of recent bottlenecks (p < 0.05) and inbreeding. The results suggest a potential decline in genetic diversity and increased population structuring (ΦST = 0.274, p < 0.01) over the past decades compared to the previous study on old trees. The observed genetic patterns indicate ongoing impacts of habitat fragmentation and anthropogenic pressures on A. guatemalensis. Conservation efforts should prioritise expanding effective population sizes and facilitating gene flow, particularly for isolated populations. While restoration efforts may be logistically easier within mountain ranges, genetic evidence suggests that increasing overall population connectivity could benefit this species. Management strategies should implement systematic seed collection protocols to maintain genetic diversity in future populations. These findings highlight the urgent need for conservation measures to preserve remaining genetic diversity and promote connectivity among A. guatemalensis populations. [ABSTRACT FROM AUTHOR]

Copyright of Bosque (03048799) is the property of Facultad de Ciencias Forestales, Universidad Austral de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Frosty pod rot (FPR) disease, caused by Moniliophthora roreri, is the most important cocoa disease in the Western Hemisphere. In Guatemala, the presence of the pathogen is attributed to a rapid and clonal dissemination throughout Central America after one or very few introductions of M. roreri from South America. We analyzed the genetic diversity of isolates from the main cocoa producing departments in Guatemala using AFLP. In total, 15 different multilocus genotypes were found among 119 isolates, indicating a low genetic diversity (percentage of polymorphic loci and Nei's gene diversity, 12.28% and 0.321, respectively). The obtained linkage disequilibrium through the observed and standardized indexes of association (IA and rd) confirmed clonality and asexual reproduction in the populations of M. roreri. The discriminant analysis of principal components suggested three genetic groups; nonetheless, the minimum spanning network and fixation index (ΦST = 0.043 P = 0.09) revealed a weak population structure, mainly attributed to high human-mediated gene flow (Nm = 11.13). Given the high mutation rate of M. roreri, constant monitoring of its evolution is suggested along with quarantine practices that limit its dispersal and evaluation of cocoa clones tolerant to the new genotypes of M. roreri, thus preventing increases in losses of Guatemalan cocoa production. [ABSTRACT FROM AUTHOR]

Data on demographic characteristics and therapeutic approaches in Latin American pulmonary arterial hypertension (PAH) patients are scarce. Pulmonary Hypertension Mexican registry (REMEHIP) is a multicenter Mexican registry of adult and pediatric patients, including prevalent and incident cases. Objective: assess clinical characteristics, treatment trends, and in‐hospital outcomes. Inclusion: age >2 years, diagnosis of pulmonary hypertension (PH) (groups 1 and 4), right heart catheterization with mPAP ≥25 mmHg, PWP ≤ 15 mmHg, and PVR > 3 Wood unit (WU). We included 875 PH patients, 619 adults, 133 pediatric idiopathic PAH (IPAH), and 123 chronic thromboembolic pulmonary hypertension (CTEPH) patients. We enrolled 48.4% of the incident and 51.6% of the prevalent adult and pediatric patients. PAH adults: age 43 ± 15, females 81.9%, functional class (FC) (I/II) 66.5%, 6‐min walk distance (6MWD) 378 ± 112 m, mPAP 57.3 ± 19.0 mmHg, confidence interval (CI) 3.3 ± 1.5 L/min/m2, PVR 12.0 ± 8.1 WU. PAH pediatrics: age 9 ± 5, females 51.1%, FC (I/II) 85.5%, 6MWD 376 ± 103 m, mPAP 49.7 ± 13.4 mmHg, CI 2.6 ± 0.9 L/min/m2, PVR 16.4 ± 13.5 WU. CTEPH: age 44 ± 17, females 56.1%, FC (I/II) 65.5%, 6MWD 369 ± 126 m, mPAP 49.7 ± 13.4 mmHg, CI 2.6 ± 0.9 L/min/m2, PVR 10.5 + 6.5 WU. When we analyzed the IPAH group separately, it sustained a high functional class I/II incidence. REMEHIP shows better functional class in young females with severe PAH than in American and European patients. Also, PAH pediatric patients had a better functional class than other registries. However, our registry also shows that our population's access to specific pharmacologic treatments is still far from optimal. [ABSTRACT FROM AUTHOR]

Copyright of Salud, Ciencia y Tecnología is the property of Fundacion Salud, Ciencia y Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Guatemala's wild avocado germplasm holds vital genetic value, but lacking conservation strategies imperils it. Studying its diversity is pivotal for conservation and breeding. The study aimed to comprehensively assess the wild avocado germplasm in Guatemala by combining phenotypic and genotypic data and to create a core collection for conservation and future breeding programs. A total of 189 mature avocado trees were sampled across Guatemala's northern, southern, and western regions. Morphological characteristics were documented, and genetic diversity was assessed using 12 SSR loci. The investigated germplasm revealed three distinct genetic clusters, exhibiting an average gene diversity of 0.796 and a 7.74% molecular variation among them. The samples showed various morphological characteristics that indicate the presence of three avocado races in Guatemala. The weak correlation between phenotypic and genotypic distances highlighted their independence and complementary nature. The joint matrix effectively integrated and captured genotypic and phenotypic data for comprehensive genetic diversity analysis. A core collection comprising 20% of total accessions that captured maximum genetic diversity was formed. This study exposed wild Guatemalan avocados' genetic diversity, morphological traits, and conservation significance. Integrated data capture via clustering validates holistic genetic insight for conservation and breeding strategies. [ABSTRACT FROM AUTHOR]

Copyright of Páginas de la Educación is the property of Universidad Catolica del Uruguay Damaso Antonio Larranaga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Even though Guatemala is considered one of the three domestication centres of the avocado (Persea americana Mill), little is known about the genetic diversity of its native populations. This is the first study to explore avocado genetic diversity and population structure in native dispersal areas using microsatellite markers. We sampled 189 avocado trees grown from seeds in eight geographical populations, and 12 microsatellite loci were tested for diversity. There were a total of 289 alleles found throughout the 12 loci, with an average of 23.83 alleles per locus. The average observed and expected heterozygosity were 0.53 and 0.83, respectively. The analysis of molecular variance revealed that the eight populations comprised around 2% of the variation. Five of the 28 G'ST(Nei) pairwise comparisons indicated no genetic difference. We discovered a mixture of avocado trees from various populations using unweighted pair group method with arithmetic mean (UPGMA) hierarchical cluster analysis. The sampled individuals were classified into three main genetic clusters by the model-based STRUCTURE and discriminant analysis of principal components (DAPC). The weak genetic structure exhibited by mixing avocado trees from different populations could be mainly attributed to high human-mediated gene flow (Nm = 12.25) due to avocado's importance in food, culture, and Guatemala's religion. The high genetic diversity found in the avocado germplasm suggests that it might be a valuable source of variable alleles that could be used in breeding programs for this crop in Guatemala. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Gastroenterología del Perú is the property of Sociedad de Gastroenterologia del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciencia, Tecnología y Salud is the property of Ciencia, Tecnologia y Salud and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Small and medium enterprises (SMEs) are firms that have a wide impact on the country's economy in Colombia and contribute 28% of GDP, so it is essential to achieve the competitiveness of these organizations. The government has promoted plans to adopt information and communications technologies (ICT) at SMEs to increase their productivity and competitiveness. SMEs are organizations that lag behind in technology adoption. Several investigations have been carried out to characterize them, but no questions have been raised regarding the different types of SMEs that can be found according to their ICT implementation. This research aimed to determine the current usability and perception in the implementation of ICT and subsequently classify organizations based on these two factors. The results describe five types of SMEs: those that experience, those that have been negligent, those that lag behind, those that hesitate, and those that improvise. The data were collected in 2019, reflecting the state of SMEs before the lockdown due to the SARS-CoV-2 virus outbreak. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Technological Prototypes / Revista de Prototipos Tecnológicos is the property of ECORFAN-Mexico S.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dilemas Contemporáneos: Educación, Política y Valores is the property of Dilemas Contemporaneos: Educacion, Politica y Valores and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An experimental fluid-dynamic study of sand-forest biomass mixture fluidization was conducted. Different proportions of biomass/sand were tested. Sawdust from the Abra Ancha sawmill, located in the town of Aluminé, Argentina, was adopted as the forest biomass material. In parallel, computational fluid dynamics (CFD) simulations of the fluidization process of these mixtures were performed to obtain exhaustive knowledge of their fluid-dynamic behavior. As a result, sand incorporation, even at low concentrations, reduces the cohesion and bonding forces between biomass particles and decreases the segregation and preferential channel formation in sawdust, thus improving fluidization. Satisfactory qualitative results were obtained in relation to the agitation state, bed expansion, and formation of bubbles in the different fluidized mixtures analyzed. The occurrence of two different fluidization regimes was confirmed in both the biomass and biomass-sand mixtures. This phenomenon allows the definition of the incipient ( U i f ) and complete ( U c f ) fluidization velocities. The potential of ANSYS-Fluent software as a simulation tool of sand-sawdust mixture fluidization was verified, and a suitable simulation methodology for predicting the minimum fluidization velocity was developed. This study constitutes the first and most indispensable stage to achieve complete simulation, including chemical reactions, of a sawdust fluidized bed gasification reactor. [ABSTRACT FROM AUTHOR]

Aims: Little is known regarding acute heart failure (AHF) clinical characteristics and its hospital outcome in Latin America. This study sought to assess the prevalence of, and identify differences among, in‐hospital outcomes in patients hospitalized for AHF who were stratified by clinical phenotype at a hospital in Latin America. Methods and results: This is a retrospective cohort study of patients with AHF who were hospitalized in the coronary care unit of a Latin American teaching hospital from January 2006 to December 2018. Cox regression analysis was used to identify predictors of mortality. Of 21 042 patients admitted, 7759 (36.6%) had AHF. Their median age was 62 years, and 35% were women. De novo heart failure was seen in 39.4% of patients. Most common was AHF‐associated acute coronary syndromes (ACS‐HF) in 43.0%, decompensated heart failure (DHF) in 33.7%, hypertensive heart failure (HT‐HF) in 11.8%, and cardiogenic shock (CS) in 5.2%. Pulmonary oedema (PO) (3.3%) and right heart failure (RHF) (3.0%) were least frequent. Coronary artery disease was the most frequent aetiology in 56.5% of patients, valvular heart disease in 22.4%, and cardiomyopathies in 12.3%. Other less frequent aetiology included adult congenital heart disease (2.5%), lung diseases (2.1%), acute aortic syndromes (1.4%), pericardial diseases (0.8%), and intracardiac tumours (0.3%). Aetiology could not be established in 1.6% of patients. Before admission, patients with worsening chronic heart failure and reduced ejection fraction were treated with renin–angiotensin system blockers (60.4%), beta‐blockers (42.5%), or spironolactone (34.4%). The percentages of patients given in‐hospital management with intravenous diuretics, vasodilators, inotropes, and vasopressors were 81.2%, 33.4%, 18.9%, and 20.4%, respectively. The overall in‐hospital mortality was 17.9% (71.3%, 43.9%, 23.8%, 14.9%, 13.6%, and 10.1% for CS, PO, RHF, DHF, ACS‐HF, and HT‐HF, respectively; P < 0.0001). Multivariate analysis revealed that PO (hazard ratio [HR] 2.68, 95% confidence interval [CI] 1.73–4.14, P < 0.0001) and CS (HR 3.37, 95% CI 2.12–5.35, P < 0.0001) were independent predictors of in‐hospital mortality. Use of intravenous diuretics was linked to reduction of in‐hospital mortality (HR 0.70, 95% CI 0.59–0.59, P < 0.0001). By contrast, increased in‐hospital mortality was associated with the use of intravenous inotrope or vasopressor (HR 1.49, 95% CI 1.27–1.76 and HR 2.91, 95% CI 2.41–3.51, P < 0.0001, respectively). Conclusions: Real‐world evidence from a university hospital in Latin America shows that the high mortality among patients with AHF may depend, among other factors, on patients' AHF clinical phenotypes. The clinical characteristics and aetiologies of AHF appear to differ between these data from Mexico and those from European and US registries. [ABSTRACT FROM AUTHOR]

Pulmonary arterial hypertension (PAH) is an uncommon but lethal and progressive disease in which prostacyclin, nitric oxide and endothelin-1 pathways are disturbed and contribute to the pathophysiology of this disease. Endothelin receptor antagonists are a class of drugs that have been approved as PAH therapy. Macitentan is a lipophilic, tissue specific, dual receptor antagonist with a higher potency than bosentan and a reduced risk of hepatic injury. Macitentan has shown a reduction in morbidity and mortality due to PAH at long-term follow-up and improvements in hemodynamics, exercise capacity and functional class at the short term. Its main adverse events are nasopharyngitis, bronchitis and an increased risk of anemia. We review the clinical data of macitentan and its use in PAH. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia, Tecnología y Salud is the property of Ciencia, Tecnologia y Salud and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciencia, Tecnología y Salud is the property of Ciencia, Tecnologia y Salud and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciencia, Tecnología y Salud is the property of Ciencia, Tecnologia y Salud and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Equidad y Desarrollo is the property of Equidad y Desarrollo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Criterio Libre is the property of Revista Criterio Libre and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)