Abstract The moorland or paramo is a threatened ecosystem. The indiscriminate advance of the agricultural frontier is producing the loss of ecosystem services, especially water service. This research estimated the willingness to pay (WTP) of the water users corresponding to the Municipality of Riobamba for the conservation of the water service in the Micro-basin of the Chimborazo River (MCRCH). Four hundred and six surveys were applied by means of the double limit dichotomous contingent valuation method, using a maximum likelihood model in the Stata software. Four models were developed: simple limit, simple limit with other explanatory variables, double limit, and double limit with other explanatory variables, the latter being statistically more significant. As a result, it was determined that the WTP is USD 0.84 per month to conserve the water service of the MCRCH, value that increases if the home ownership variable is included in USD 0.04. The problem of climate change increases in USD 0.24, while the variable level of education decreases the WTP by USD 0.04.

Resumen El páramo es un ecosistema amenazado pues el avance indiscriminado de la frontera agrícola está produciendo la pérdida de servicios ecosistémicos, especialmente del servicio hídrico. Esta investigación estimó la disposición a pagar (DAP) de los usuarios de agua del Municipio de Riobamba, por la conservación del servicio hídrico de la Microcuenca del Río Chimborazo (MCRCH). Se aplicaron 406 encuestas, mediante el método de valoración contingente dicotómico de doble límite, usando un modelo de máxima verosimilitud en el software Stata. Se desarrollaron cuatro modelos de simple límite, de simple límite con otras variables explicativas, de doble límite y de doble límite con otras variables explicativas, siendo este último estadísticamente más significativo. Como resultado se determinó que la DAP es de USD 0,84 mensuales para conservar el servicio hídrico de la MCRCH, valor que se incrementa si se incluye la variable vivienda propia en USD 0,04 y al reconocer el problema del cambio climático en USD 0,24, mientras que la variable nivel de educación disminuye la DAP en USD 0,04.

Resumo As florestas do Piemonte, no sul do Equador, abrigam uma composição única de espécies florestais, o que lhes confere um valor excepcional do ponto de vista da conservação e do manejo sustentável. O objetivo deste estudo foi avaliar a composição, estrutura, diversidade e potencial de armazenamento de carbono de uma floresta perene do Piemonte na cordilheira Cóndor-Kutukú. Foram estabelecidas cinco parcelas amostrais de 20 × 20 m, nas quais foram registrados todos os indivíduos lenhosos, incluindo palmeiras, com diâmetro à altura do peito (DAP) ≥ 10 cm. O inventário florístico identificou um total de 48 espécies, pertencentes a 38 gêneros e 21 famílias botânicas. A estrutura vertical da floresta apresentou distribuição em forma de sino, com maior concentração de indivíduos no estrato intermediário (10-19,99 m). A estrutura horizontal apresentou uma distribuição em J invertido, típica de comunidades florestais autossustentáveis. A área de estudo apresentou diversidade moderada, com índice de Shannon-Wiener de 3,36. A biomassa acima do solo atingiu um valor de 287,58 Mg ha⁻¹, o que equivale a um estoque estimado de carbono armazenado de 135,16 Mg ha⁻¹. As espécies com maior importância ecológica foram Aniba muca e Wettinia maynensis, destacando-se pela abundância e biomassa. Este estudo ressalta a necessidade de implementar estratégias de gestão e conservação que protejam a funcionalidade desses ecossistemas e promovam sua sustentabilidade diante das crescentes pressões humanas.

Abstract The piemont forests of southern Ecuador harbor a unique composition of forest species, giving them exceptional value from the perspective of conservation and sustainable management. The objective of this study was to evaluate the composition, structure, diversity, and carbon storage potential of a Piemont Evergreen Forest in the Cordillera del Cóndor-Kutukú. Five 20 × 20 m sampling plots were established, in which all woody individuals, including palms, with a diameter at breast height ≥ 10 cm were recorded. The floristic inventory identified a total of 48 species belonging to 38 genera and 21 botanical families. The vertical structure of the forest presented a bell-shaped distribution, with a higher concentration of individuals in the intermediate stratum (10-19.99 m). The horizontal structure showed an inverted J distribution, typical of self-sustaining forest communities. The study area presented moderate diversity, with a Shannon-Wiener index of 3.36. Aboveground biomass reached 287.58 Mg ha⁻¹, equivalent to an estimated stored carbon stock of 135.16 Mg ha⁻¹. The species with the highest ecological importance were Aniba muca and Wettinia maynensis, notable for their abundance and biomass. This study highlights the need to implement management and conservation strategies that protect the functionality of these ecosystems and promote their sustainability in the face of increasing anthropogenic pressures.

Resumen Los bosques piemontanos del sur de Ecuador albergan una composición única de especies forestales, lo que les otorga un valor excepcional desde el punto de vista de la conservación y el manejo sostenible. El objetivo de este estudio fue evaluar la composición, estructura, diversidad y el potencial de almacenamiento de carbono de un bosque siempreverde piemontano de la Cordillera del Cóndor-Kutukú. Se establecieron cinco parcelas de muestreo de 20 × 20 m, en las cuales se registraron todos los individuos leñosos, incluidas las palmas, con un diámetro a la altura del pecho (DAP) ≥ 10 cm. El inventario florístico permitió identificar un total de 48 especies, pertenecientes a 38 géneros y 21 familias botánicas. La estructura vertical del bosque presentó una distribución en forma de campana, con una mayor concentración de individuos en el estrato intermedio (10-19,99 m). La estructura horizontal mostró una distribución de J invertida, típica de comunidades forestales autosustentables. El área de estudio presentó una diversidad moderada, con un índice de Shannon-Wiener de 3,36. La biomasa aérea alcanzó un valor de 287,58 Mg ha⁻¹, lo que equivale a un stock de carbono almacenado estimado en 135,16 Mg ha⁻¹. Las especies con mayores valores de importancia ecológica fueron Aniba muca y Wettinia maynensis, destacándose por su abundancia y biomasa. Este estudio subraya la necesidad de implementar estrategias de manejo y conservación que protejan la funcionalidad de estos ecosistemas y promuevan su sostenibilidad ante las crecientes presiones antrópicas.

Resumen: La prevalencia global de la Leucomalacia Periventricular (LPV) se ha mantenido estable, en torno al 4%, en recién nacidos de muy bajo peso al nacer (RNMBPN) en la Red Neonatal NEOCOSUR durante 16 años. Objetivo: Determinar los factores asociados a la presencia de LPV en aquellos RNMBPN sobrevivientes al alta, su incidencia global y por edad gestacional (EG). Pacientes y Método: Estudio observacional, multicéntrico, retrospectivo con datos registrados prospectivamente (período 20122021). Se incluyeron aquellos con peso de nacimiento entre 400 a 1.500 gramos y 23 a 31+6 semanas de EG sobrevivientes al alta. Se realizó un análisis bivariado utilizando la prueba chi-cuadrado de Pearson para contrastar el porcentaje de LPV para variables categóricas y t-Student para contrastar promedios para variables numéricas. Para explorar el efecto independiente de cada variable explicativa se realizó un análisis de regresión logística multivariado. Resultados: En 6825 RNMBPN sobrevivientes, la incidencia global de LPV fue del 8,5%. Los factores asociados a mayor probabilidad de LPV fueron displasia broncopulmonar (DBP) [OR 2,27 IC 95% 1,80-2,87], enterocolitis necrotizante (ECN) [OR 1,78 IC 95% 1,35-2,34], sepsis tardía [OR 1,71 IC 95% 1,34-2,19], hemorragia intracraneana (HIC) severa [OR 4,64 IC 95% 3,51-6,14], Ductus Arterioso (DAP) [OR 1,32 IC 95% 1,06-1,64] y ventilación mecánica (VM) [OR 2,03 IC 95% 1,54-2,67]. Conclusión: En RNMBPN sobrevivientes al alta, una mayor probabilidad de LPV se asoció a la presencia de DBP, ECN, sepsis tardía, HIC severa y DAP; y al empleo de VM.

Abstract: The global prevalence of Periventricular Leukomalacia (PVL) has remained stable (~4%) in very low birth weight (VLBW) infants in the NEOCOSUR Neonatal Network for 16 years. Objective: To determine the factors associated with the presence of PVL in surviving VLBW infants at discharge, its overall incidence, and gestational age (GA). Patients and Method: Observational, multicenter, retrospective study with prospectively recorded data (period 2012-2021). Newborns with birth weight between 400 to 1500 g and 23 to 31+6 weeks of GA surviving at discharge were included. A bivariate analysis was performed using Pearson’s chi-square test to contrast the percentage of PVL for categorical variables and the student’s t-test to contrast averages for numerical variables. To explore the independent effect of each explanatory variable, a multivariate logistic regression analysis was performed. Results: In 6,825 surviving VLBW newborns, the global incidence of PVL was 8.5%. Factors associated with increased likelihood of PVL were bronchopulmonary dysplasia (BPD) [OR 2.27; 95% CI 1.80-2.87], necrotizing enterocolitis (NEC) [OR 1.78; 95% CI 1.35-2.34], late-onset sepsis (LOS) [OR 1.71; 95% CI 1.34-2.19], severe intraventricular hemorrhage (IVH) [OR 4.64; 95% CI 3.51-6.14], patent ductus arteriosus (PDA) [OR 1.32; 95% 1.06-1.64], and mechanical ventilation (MV) [OR 2.03; 95% CI 1.54-2.67]. Conclusion: In surviving VLBW infants at discharge, a higher probability of PVL was associated with the presence of BPD, NEC, LOS, severe IVH, and PDA and the use of MV.

Resumen: El ductus arterioso es una estructura vascular vital en la vida fetal, sin embargo, su persistencia posterior al nacimiento se ha asociado con incremento de la morbilidad y mortalidad. Recientemente se ha propuesto al paracetamol como una alternativa para su cierre farmacológico, no obstante, se requiere información acerca de su perfil de seguridad y de efectividad. Objetivo: Evaluar la eficacia, seguridad y la relación costo-beneficio del paracetamol en neonatos para el cierre del ductus arterioso persistente. Material y Método: Revisión sistemática de acuerdo con la guía PRISMA, entre los años 2019 a 2023 en las bases de datos PubMed y Embase del uso de paracetamol en neonatos para el cierre del ductus arterioso persistente (DAP). Resultados: Se identificaron 210 estudios, luego de aplicar los criterios de inclusión y exclusión se seleccionaron 36, los cuales se clasificaron en 7 categorías de análisis y descripción. La mayoría de los estudios cuenta con un número limitado de pacientes prematuros menores de 28 semanas, que presentan un alto porcentaje de DAP. Se concluye que el paracetamol tiene una eficacia para el cierre de DAP entre el 69% y 80%, disminuyendo cuando se inicia el tratamiento en la segunda semana o posterior. Conclusiones: la evidencia científica actual demuestra que comparado con ibuprofeno e indometacina, el paracetamol tiene tasas de éxito similares en el cierre farmacológico del ductus persistente. Se observó un mejor perfil costo-beneficio y existen elementos que sugieren disminución de efectos adversos.

Abstract: The ductus arteriosus is a vital vascular structure in fetal life, however, its persistence after birth has been associated with increased morbidity and mortality. Acetaminophen has recently been proposed as an alternative for its pharmacological closure, however, information about its safety and effectiveness profile is required. Objective: To evaluate the efficacy, safety, and cost-benefit ratio of acetaminophen in neonates for the closure of patent ductus arteriosus. Material and Method: Systematic review according to the PRISMA guidelines, between 2019 and 2023 in the PubMed and Embase databases of the use of acetaminophen in neonates for the closure of patent ductus arteriosus (PDA). Results: 210 studies were identified and, after applying the inclusion and exclusion criteria, 36 were selected, which were classified into 7 categories of analysis and description. Most studies have a limited number of premature patients under 28 weeks, who have a high percentage of PDA. It is concluded that acetaminophen has an efficacy for PDA closure between 69% and 80%, decreasing when treatment is started in the second week or later. Conclusions: Current scientific evidence shows that, compared to ibuprofen and indomethacin, acetaminophen has similar success rates in the pharmacological closure of the patent ductus. A better cost-benefit profile was observed, and some elements suggest a decrease in adverse effects.

Abstract In this study, the effect of six macro fertilizers i.e. urea, ammonium sulfate, ammonium nitrate, NPK, NP & DAP, and three micro elements i.e. Zn, Mn, and Fe at different concentrations as well as eight novel pesticides, thiamethoxam, spinetoram, azoxystrobin, chlorfenpyr, chlorantraniliprole, novaluron, lambda-cyhalothrin and avaunt at field recommended rate on two entomopathogenic nematodes (EPNs): Steinernema carpocapsae and Heterorhabditis bacteriophora were determined under laboratory conditions. The obtained results reported that S. carpocapsae was more tolerant to NPK; NP and DAP macro fertilizers than H. bacteriophora, showed the lowest mortality percentages (12.63, 9.47and12.63%), (15.79, 13.68 and 31.58%) and (20.21, 30.85 and 34.04%) at three tested concentrations (1g/liter water, 5g/liter water and10g/liter water), respectively. All tested micro fertilizers (Zn, Mn, and Fe) were lethal for two EPNs and induced 94.85, 100, 100 mortality % after five days of exposure. The morality percent increased as the concentration of fertilizers increased. With respect to tested pesticides, the mortality percentages of two EPN were ranged between 2.67-23.67% for S. carpocapsae and 3.33-18.33% for H. bacteriophora after five days of exposure. The tested macro fertilizers such as DAP, NP and NPK can be used safely at tested concentrations (5-10 g/ liter water) with Steinernema carpocapsae. All tested macro fertilizers cannot be used with Heterorhabditis bacteriophora. All micro fertilizers could be used with two EPNs. All tested pesticides can be successfully used for integrated plant protection systems. EPNs are tolerant to the tested pesticides and the tank-mix application is possible in most compounds except Lambda cyhalothrin which significantly reduced the virulence of tested nematodes.

Resumo Neste estudo, o efeito de seis macrofertilizantes, ou seja, ureia, sulfato de amônio, nitrato de amônio, NPK, NP e DAP, e três microelementos, ou seja, Zn, Mn e Fe, em diferentes concentrações, bem como oito novos pesticidas − tiametoxame, espinetoram, azoxistrobina, clorfenpir, clorantraniliprole, novaluron, lambda-cialotrina e avante − na taxa recomendada em campo, em dois nematoides entomopatogênicos (EPNs): Steinernema carpocapsae e Heterorhabditis bacteriophora, foi determinado em condições de laboratório. Os resultados obtidos relataram que S. carpocapsae foi mais tolerante ao NPK; com os macrofertilizantes NP e DAP, H. bacteriophora apresentou os menores percentuais de mortalidade (12,63, 9,47 e 12,63%), (15,79, 13,68 e 31,58%) e (20,21, 30,85 e 34,04%), nas três concentrações testadas (1g/litro de água, 5g/litro de água e 10g/litro de água), respectivamente. Todos os microfertilizantes testados (Zn, Mn e Fe) foram letais para duas EPNs e induziram 94, 85 e 100% de mortalidade após cinco dias de exposição. A percentagem de mortalidade aumentou à medida que a concentração de fertilizantes aumentou. Com relação aos agrotóxicos testados, os percentuais de mortalidade dos dois EPNs variaram entre 2,67 e 23,67% para S. carpocapsae e 3,33 e 18, 33% para H. bacteriophora após cinco dias de exposição. Os macrofertilizantes testados, como DAP, NP e NPK, podem ser usados com segurança nas concentrações testadas (5-10 g/litro de água) com Steinernema carpocapsae. Todos os macrofertilizantes testados não podem ser usados com Heterorhabditis bacteriophora. Todos os microfertilizantes poderiam ser usados com os dois EPNs. Todos os pesticidas testados podem ser utilizados com sucesso em sistemas integrados de proteção fitossanitária. Os EPNs são tolerantes aos pesticidas testados e a aplicação em mistura em tanque é possível na maioria dos compostos, exceto lambda-cialotrina, que reduziu significativamente a virulência dos nematoides testados.

ABSTRACT Phosphorus (P) is a limiting nutrient for coffee seedlings. To meet this requirement, coffee growers usually apply di-ammonium phosphate (DAP), which is highly sensitive to local price fluctuations. The use of arbuscular mycorrhizal fungi (AMF) and phosphate-solubilizing fungi (PSF) has been recommended, but the results derived from their application are inconsistent and uncertain, depending on soil fertility status. The response of AMF and PSF application in the plant growth of coffee seedlings during the nursery stage was evaluated in four non-sterile soils, which represent the most abundant type of soils in the coffee regions of Colombia: Eutropept, Dystropept, Fulvudand, and Ultisol. The treatments included a commercial AMF inoculum, PSF-Phlebia subserialis-CH4, and a consortium of AMF+PSF, at four P levels (0, 0.5, 1, and 2 g.plant-1 P2O5) using DAP fertilizer. Shoot dry weight (SDW) was affected by P applications in Fulvudand. In the other soils, a P-response occurred with 0.5 g.plant-1 , whereas 1 and 2 g.plant-1 of P2O5 caused a significant reduction in SDW. AMF increased SDW by 40% in Eutropept. The negative effect of higher P amounts was mitigated (> 70%) through PSF and AMF+PSF in Ultisol and Eutropept, respectively. In plants in which microorganisms increased SDW, the P concentration was 0.17 to 0.22%. The plant growth promotion of coffee seedlings during the nursery stage with AMF and/or PSF applications varied according to soil type and P amounts applied.

Resumo A doença arterial periférica (DAP) nos membros inferiores é altamente prevalente, e as diretrizes atuais recomendam o uso do ultrassom Doppler (UD) com análise espectral para diagnóstico. Esta revisão sistemática e metanálise avaliou a acurácia diagnóstica do UD em pacientes sintomáticos com DAP. Foram pesquisados estudos em bancos de dados eletrônicos que comparassem UD e arteriografia. As artérias foram analisadas individualmente e agrupadas em segmentos: aortofemoral comum, femoropoplíteo, abaixo do joelho e todo o membro inferior. A metanálise estimou sensibilidade, especificidade, verossimilhança e razão de chances diagnóstica (DOR). Quinze estudos foram incluídos, analisando 9.067 artérias. A acurácia do UD para DAP sintomática foi de 0,86 (intervalo de confiança de 95% [IC 95%] 0,81-0,90) para sensibilidade e 0,95 (IC 95% 0,78-0,97) para especificidade. O segmento femoropoplíteo apresentou os melhores resultados, com sensibilidade de 0,86 (IC 95% 0,80-0,90) e especificidade de 0,95 (IC 95% 0,93-0,97). O segmento abaixo do joelho teve o pior desempenho, com sensibilidade de 0,78 (IC 95% 0,60-0,89) e especificidade de 0,92 (IC 95% 0,78-0,97). A maioria dos estudos apresentou risco de viés alto e incerto. Observou-se heterogeneidade significativa nos resultados, com número limitado de estudos primário para cada artéria, especialmente para o segmento abaixo do joelho.

Abstract Lower limb peripheral artery disease (PAD) is highly prevalent. Current guidelines recommend duplex ultrasound (DUS) with spectral analysis for diagnosis. This systematic review and meta-analysis assessed the diagnostic accuracy of DUS in symptomatic PAD patients. We searched electronic databases for studies comparing DUS and arteriography. Arteries were analyzed individually and grouped into segments (aorto-common femoral, femoropopliteal, below the knee, and the entire lower limb). The meta-analysis estimated sensitivity, specificity, likelihood, and diagnostic odds ratios (DOR). Fifteen studies were included, analyzing 9,067 arteries. DUS accuracy for symptomatic PAD was 0.86 (95% CI 0.81-0.90) for sensitivity and 0.95 (95% CI 0.78-0.97) for specificity. The best results were observed for the femoropopliteal segment: sensitivity 0.86 (95% CI 0.80-0.90), specificity 0.95 (95% CI 0.93-0.97). The poorest performance was observed for the below-the-knee segment: sensitivity 0.78 (95% CI 0.60-0.89), specificity 0.92 (95% CI 0.78-0.97). Most studies had high and unclear risk of bias. There is significant heterogeneity in results, with a limited number of primary studies for each arterial segment, especially for the below-the-knee segment.

RESUMO Contexto Há poucos estudos que descrevem a prevalência da doença arterial periférica (DAP) na população diabética no Brasil. Objetivos Avaliar a prevalência de DAP e sua associação com a presença de claudicação e comparar fatores de risco para aterosclerose entre indivíduos com e sem DAP. Métodos Estudo analítico, observacional, prospectivo e transversal, realizado com 150 voluntários com Diabetes Mellitus tipo 2 (DM2) em tratamento no ambulatório universitário de endocrinologia da Universidade Federal do Paraná (Curitiba, Brasil). Os participantes foram avaliados pelo índice tornozelo-braquial (ITB) e pelo Questionário de Claudicação de Edinburgh. Resultados O ITB foi avaliado em 143 voluntários (7 não atenderam aos critérios de inclusão). Seis indivíduos apresentaram ITB > 1,4. Excluindo esses casos e adotando o ITB ≤ 0,9 para a definição de DAP, a prevalência da doença foi de 14,6% (20 de 137), sendo 15,8% em homens (6 de 38) e 14,1% em mulheres (14 em 99). Além disso, 25 participantes apresentaram ITB limítrofe (18,2%). A claudicação esteve presente em 25% dos indivíduos com DAP, mas apenas 15% apresentaram claudicação típica. A associação entre DAP e claudicação típica foi significativa apenas quando os grupos foram estratificados para valores de ITB acima ou abaixo que 1,0 (p = 0,04, teste exato de Fisher). Os participantes com DAP eram mais velhos (diferença de medianas: 5,5 anos; intervalo de confiança de 95% de 3,0-9,0; p < 0,001) e apresentaram tendência a maior duração do DM e maior índice de massa corporal. Conclusões A prevalência de DAP em indivíduos com DM2, sem triagem prévia, foi de 14,6%, sendo 75% assintomáticos.

ABSTRACT Background Few studies have described the prevalence of peripheral arterial disease (PAD) in the diabetic population of Brazil. Objectives To evaluate the prevalence of PAD and its association with the presence of claudication and to compare risk factors for atherosclerosis between subjects with and without PAD. Methods An analytical, observational, prospective, cross-sectional study was conducted with 150 volunteers with type 2 Diabetes Mellitus (T2DM) treated at a university endocrinology outpatient clinic (Federal University of Paraná, Curitiba, Brazil) and assessed using the ankle-brachial index (ABI) and the Edinburgh Claudication Questionnaire. Results ABI was evaluated in 143 volunteers (7 did not meet the inclusion criteria). Six individuals had an ABI > 1.4. Excluding these cases and adopting an ABI ≤ 0.9 to identify PAD, the prevalence of PAD was 14.6% (20 of 137), 15.8% in men (6 of 38), and 14.1% in women (14 of 99). We identified twenty-five participants with borderline ABI (18.2%). Claudication was present in 25% of subjects with PAD; however, only 15% had typical claudication. A significant association with the presence of typical claudication was observed only when ABI values were stratified above or below 1.0 (p = 0.04, Fisher’s exact test). Participants with PAD were older (median difference: 5.5 years, 95% CI 3.0 to 9.0, p < 0.001) and tended to have a longer duration of DM and higher BMI. Conclusions The prevalence of PAD in T2DM volunteers with no prior screening was 14.6% and 75% were asymptomatic.

ABSTRACT. Atemoya has a short post-harvest shelf life due to its high metabolic activity. Limited information is available on the optimal harvest time for atemoya grown in semi-arid conditions. This study aimed to evaluate the quality of atemoya fruits at various maturity stages under semi-arid conditions. Fruit was harvested from a commercial orchard and the experiment was conducted in a completely randomized design (CRD) with a 3x5 factorial scheme. This included three maturation stages (100, 105, and 110 days after pollination - DAP) and five refrigerated storage periods (0, 3, 6, 9, and 12 days), with four repetitions. The fruits were stored at 15 ± 2°C and 74 ± 2% RH and subjected to physical, chemical, and biochemical evaluations. Throughout storage, there was a significant fresh mass loss of 13.83, 11.99, and 11.92% for fruits harvested at 100, 105, and 110 DAP, respectively. Firmness and starch content also decreased as starch was converted into sugars. Across all maturation stages, the shelf life was limited to nine days due to compromised appearance, primarily cracks and peel darkening. Fruits harvested at 105 and 110 DAP exhibited better quality at the end of storage, including improved appearance, greater mass, lower weight loss, and higher soluble solids and vitamin C content. The results suggest that atemoya fruits can be harvested between 105 and 110 DAP under semi-arid conditions. Thus, atemoya shows commercial potential for production in the semi-arid region.

Resumen Los bosques de piedemonte son ecosistemas con gran diversidad florística respecto a otras áreas de la Orinoquía. En este estudio se caracterizaron la estructura y composición florística de un bosque de piedemonte en 0.1 ha, donde se midieron todos los individuos con DAP ≥ 2.5 cm. Los 288 individuos registrados estuvieron distribuidos en 71 especies, 59 géneros y 33 familias. Las familias con mayor número de especies fueron Lauraceae (9 spp.) y Rubiaceae (9). Los géneros más representativos fueron Aniba (4 spp.), Miconia y Palicourea (3 spp. cada una). Las especies de mayor importancia ecológica en la comunidad fueron Ciliosemina pedunculata (62.6 %), Warszewiczia coccinea (39.4 %) y Socratea exorrhiza (23.5 %). Las familias más importantes fueron Rubiaceae (142.8 %), Lauraceae (18.0 %) y Arecaceae (15.1 %). La mayoría de los individuos se encontraron en los rangos más bajos de clases de altura y diámetro. Se concluye que el bosque de piedemonte estudiado se encuentra en un estado de recuperación inicial.

Abstract Piedmont forests are ecosystems with great floristic diversity compared to other areas of the Orinoquía. This study characterized the structure and floristic composition of a piedmont forest in 0.1 ha, wherein all individual trees with a DBH ≥ 2.5 cm were measured. The 288 registered individuals were distributed in 71 species, 59 genera, and 33 families. The families with the highest number of species were Lauraceae (9 spp.) and Rubiaceae (9). The most representative genera were Aniba (4 spp.), Miconia, and Palicourea (3 spp. each). The species with the greatest ecological importance in the community were Ciliosemina pedunculata (62.6%), Warszewiczia coccinea (39.4%), and Socratea exorrhiza (23.5%). The most important families were Rubiaceae (142.8%), Lauraceae (18.0%), and Arecaceae (15.1%). Most of the individuals are clustered in the lower ranges of the height and diameter classes. It is concluded that the studied piedmont forest is in a state of initial recovery.

Resumen Introducción. El cambio en el uso del suelo en la Península de Yucatán ha impactado en la vegetación, con influencia en el sistema milpa que depende de dicho recurso, y en consecuencia, disminuyen la fertilidad del suelo y el rendimiento de los cultivos. La agricultura de conservación (AC) con diversificación de cultivos, labranza cero y cobertura del suelo, es una opción para mejorar la producción sustentable de alimentos. Objetivo. Evaluar el efecto de tres tratamientos con prácticas de AC en el rendimiento y componentes del grano de maíz (Zea mays L.) en la milpa. Materiales y métodos. El experimento se estableció en Yaxcabá, Yucatán. Se utilizó un diseño experimental de bloques completos al azar con un control y tres tratamientos; T1 (control): Maíz, frijol ib o frijol lima, calabaza+fertilización con fosfato diamónico (DAP), T2: Maíz, frijol ib o frijol lima, calabaza + fertilización con estiércol ovino (EO), T3: Maíz, lenteja de milpa o frijol gandúl, calabaza + fertilización con EO y T4: Maíz, frijol terciopelo + EO. Se aplicó 100 kg ha-1 de DAP en T1, en los demás tratamientos 4 t ha-1 de EO. Se sembró maíz de la raza Tuxpeño. Las variables dependientes fueron número de plantas, número de mazorcas, humedad del grano, coeficiente de desgrane y rendimiento de grano. Resultados. El número de plantas, humedad del grano y coeficiente de desgrane fueron similares (p>0,05) en todos los tratamientos. En el número de mazorcas y rendimiento de grano hubo significancia (p≤0,05) con un valor mayor de ambas variables en T2, el cual incrementó en 3,500 el número de mazorcas y 327 kg ha-1 el rendimiento de grano, respecto a T1. Conclusión. Con el tratamiento T2 se pudo incrementar el número de mazorcas y rendimiento de grano de maíz en la milpa desde el primer ciclo de cultivo al establecerse prácticas de AC.

Abstract Introduction.The change in land use in the Yucatan Peninsula has impacted the vegetation, and affecting on the milpa system that depends on that resource, and consequently, soil fertility and crop yields decrease. The conservation agriculture (CA) with crop diversification, minimum tillage and soil cover, is an option to improve sustainable food production. Objective. Evaluate the effect of four treatments with CA practices on the yield of maize (Zea mays L.) and their components. Materials and methods. The experiment was established in Yaxcabá, Yucatán, México. A randomized complete block experimental design with one control and three treatments were evaluated; T1 (control): Maize, frijol ib or lima bean, squash + fertilized with diammonium phosphate (DAP), T2: Maize, frijol ib or lima bean, squash+fertilized with sheep manure (SM), T3: Maize, pigeon pea, squash + SM and T4: Maize, velvet bean + SM. In T1 was applied 100 kg ha-1 of DAP and the other treatments 4 t ha-1 of SM. Maize of the Tuxpeño landrace was sowed. The depend variables were number of plants, number of cobs, maize kernel moisture, shelling coefficient and maize grain yield. Results. The number of plants, kernel, moisture and shelling coefficient were similar (p>0.05) in all treatments. There was significance difference in the number of cobs and grain yield (p≤0.05). The highest value of both variables was obtained in T2, which increased the number of cobs by 3.500 and the grain yield by 327 kg ha-1, compared to T1. Conclusion. In treatment T2, the number of cobs and grain yield of the corn from the milpa can be increased from the first crop cycle when CA practices are established.

Resumen (Objetivo). Se evaluó el manglar de Chacarita en el Pacífico Central de Costa Rica, a través de la composición florística y las poblaciones de moluscos asociados de interés comercial, con el fin de proponer actividades de aprovechamiento sustentables en el manglar. (Metodología). Mensualmente y durante un año, se realizaron visitas al área de estudio, con el propósito de establecer una base florística de árboles de mangle y medir el almacenamiento de carbono en el lugar, además, de recolectar moluscos bivalvos para analizar el estado de las poblaciones, con base en las abundancias de organismos hallados y otras características como las longitudes y la masa de estos. En los mangles, se obtuvo el diámetro de la altura de pecho (DAP en cm), la altura (m), el índice de valor de importancia (IVI) y las reservas de carbono (Mg C·ha-1). En cuanto a los moluscos, se examinaron cuatro especies de interés comercial, evaluando la longitud (cm), la masa (g) y el índice gonadosomático. Finalmente, se realizaron valoraciones económicas de los datos obtenidos en el manglar, del turismo e información histórica de pesca para el acopio de Chacarita. (Resultados). Se hallaron cinco especies de mangles, Rhizophora mangle, Rizophora racemosa, Laguncularia racemosa, Avicennia germinans y Pelliciera rhizophorae; P. rhizophorae fue la de mayor índice de valor de importancia. Se obtuvo un almacenamiento de carbono equivalente a 78.49 Mg C·ha-1. Se contabilizaron 357 organismos, de los cuales el 18 % correspondió a Anadara similis, 37.5 % a Anadara tuberculosa, 41.46 % a Leukoma spp. y 3.08 % a Mytella guyanensis. Tomando en cuenta el valor económico de las reservas de carbono y los moluscos bivalvos presentes en los muestreos, se obtuvieron valoraciones económicas de 9812.63 USD·ha-1 y 28 USD·ha-1, respectivamente. (Conclusiones). Las bajas densidades poblacionales de moluscos, especialmente del género Anadara, hacen necesario establecer medidas de gestión que permitan recuperar las poblaciones de estos. La presente investigación propone actividades de aprovechamiento sustentables, como turismo comunitario con fines educativos y culturales.

Resumo (Objetivo). O mangue de Chacarita, no Pacífico Central da Costa Rica, foi avaliado por meio da composição florística e das populações de moluscos associados de interesse comercial, com o objetivo de propor atividades de uso sustentável no mangue. (Metodologia). Foram feitas visitas mensais à área de estudo durante um ano para estabelecer uma base florística de árvores do mangue e medir o armazenamento de carbono no local, bem como para coletar moluscos bivalves para analisar o status das populações, com base na abundância de organismos encontrados e em outras características, como comprimento e massa de tais organismos. Nos manguezais, foram obtidos o diâmetro à altura do peito (DAP em cm), a altura (m), o índice de valor de importância (IVI) e as reservas de carbono (Mg C-ha-1). No que diz respeito aos moluscos, foram examinadas quatro espécies de interesse comercial., avaliando o comprimento (cm), a massa (g) e o índice gonadossomático. Por fim, foram feitas avaliações econômicas de dados de mangue, turismo e informações históricas de pesca para a coleção Chacarita. (Resultados). Foram encontradas cinco espécies de mangue, Rhizophora mangle, Rizophora racemosa, Laguncularia racemosa, Avicennia germinans e Pelliciera rhizophorae; a P. rhizophorae apresentou o índice de valor de importância mais alto. Foi obtido um armazenamento de carbono equivalente a 78.49 Mg C-ha-1. Foram calculados um total de 357 organismos, dos quais 18% correspondeu a Anadara similis, 37.5% Anadara tuberculosa, 41.46% Leukoma spp. e 3.08% Mytella guyanensis. Levando em conta o valor econômico das reservas de carbono e dos moluscos bivalves presentes nas amostras, foram obtidas avaliações econômicas de US$ 9812.63 ha-1 e US$ 28 ha-1, respectivamente. (Conclusões). As baixas densidades populacionais de moluscos, especialmente do gênero Anadara tornam necessário o estabelecimento de medidas de manejo para permitir a recuperação dessas populações. Esta pesquisa propõe atividades de uso sustentável, como o turismo comunitário para fins educacionais e culturais.

Abstract (Objective). The floristic composition and populations of associated molluscs of commercial interest of the Chacarita mangrove forest on the Central Pacific of Costa Rica were evaluated to guide proposals for sustainable exploitation activities in the mangrove forest. (Methodology). Monthly visits to the study area were conducted for one year to establish a floristic baseline of mangrove trees and measure carbon storage. Additionally, bivalve molluscs were collected to analyze the state of their populations based on the abundances of organisms found, as well as other characteristics such as length and mass. Data regarding the mangrove trees included their diameter at breast height (DBH, cm), height (m), importance value index (IVI), and carbon reserves (Mg C·ha-1). Four mollusc species of commercial interest were analyzed, using data on their length (cm), weight (g), and gonodosomatic index. Economic evaluations were also conducted using data obtained from the mangrove forest, as well as tourism and historical fishing data for the collection of Chacarita. (Results). Five species of mangroves were identified: Rhizophora mangle, Rizophora racemosa, Laguncularia racemosa, Avice germinans, and Pelliciera rhizophorae, while P. rhizophorae had the highest importance value index. The study revealed a carbon storage equivalent to 78.49 Mg C·ha-1. A total of 357 organisms were counted, with Anadara similis accounting for 18% of the total count, followed by Anadara tuberculosa (37.5%), Leukoma spp. (41.46%), and Mytella guyanensis (3.08%). When considering the economic value of carbon stocks and the bivalve molluscs obtained from the samples, economic valuations of 9,812.63 USD·ha-1 and 28 USD·ha-1 were determined, respectively. (Conclusions). The low population densities of molluscs, particularly those belonging to the Anadara genus, necessitate the establishment of management measures to facilitate the recovery of these mollusk populations. This research proposes sustainable use activities such as community tourism for educational and cultural purposes.

Resumen Introducción. El cultivo de pitahaya (Hylocereus costaricensis y H. monocanthus) está en aumento en Costa Rica, pero carece de información técnica para su manejo, como necesidades nutricionales, momentos de fertilización y comportamiento del crecimiento. Objetivo. Cuantificar y modelar el crecimiento y la absorción de nutrimentos del cultivo de pitahaya (H. costaricensis y H. monocanthus) en condiciones del trópico estacional seco de Costa Rica. Materiales y métodos. La investigación se realizó durante los años 2017-2020, en Guanacaste, Costa Rica. Se muestrearon plantas a los 76, 165, 308, 450, 607, 903, 1249 y 1706 días después de siembra (DDS) y 205 frutas. Se cuantificó la materia seca y se calculó la absorción de N, P, Ca, Mg, K, S, Fe, Cu, Zn, Mn y B. Se ajustaron dos modelos logísticos para determinar la absorción de nutrientes y se calibraron regresiones lineales en fruta fresca. Resultados. Para una densidad de siembra de 3000 planta/ha los requerimientos nutricionales del cultivo por hectárea fueron: 137 kg N, 32 kg P, 327 kg K, 63 kg Mg, 32 kg S, 1,60 kg Zn y 0,21 kg B. El modelo logístico de mejor ajuste (RMSE = 0,09) estimó de forma precisa la absorción de N, P, Ca, S, Zn y B. El modelo de regresión lineal tuvo alta capacidad predictora (R2 > 0,85) para los requerimientos de N, P, K, Mg y S en fruta. Conclusión. Los modelos logísticos tuvieron alta precisión para modelar de manera determinística la absorción de nutrientes en plantas de pitahaya. Además, se logró cuantificar y modelar de forma eficiente el comportamiento nutricional de las plantas en condiciones de trópico estacional seco de Costa Rica, lo que proporciona información esencial para los programas de fertilización del cultivo.

Abstract Introduction. The cultivation of dragon fruit (Hylocereus costaricensis and H. monocanthus) is increasing in Costa Rica, but technical information for its management, such as nutritional requirements, fertilization timing, and growth behavior, is lacking. Objective. To quantify and model the growth and nutrient uptake of dragon fruit (H. costaricensis and H. monocanthus) under dry tropics conditions in Costa Rica. Materials and methods. The research was conducted from 2017 to 2020 in Guanacaste, Costa Rica. Plants were sampled at 76, 165, 308, 450, 607, 903, 1249, and 1706 days after planting (DAP) and 205 fruits were analyzed. Dry matter was quantified, and the uptake of N, P, Ca, Mg, K, S, Fe, Cu, Zn, Mn, and B was calculated. Two logistic models were fitted to determine nutrient uptake, and linear regressions were calibrated for fresh fruit. Results. For a planting density of 3000 plants/ha, the nutritional requirements per hectare were: 137 kg N, 32 kg P, 327 kg K, 63 kg Mg, 32 kg S, 1,60 kg Zn, and 0,21 kg B. The best-fitting logistic model (RMSE = 0.09) accurately estimated the uptake of N, P, Ca, S, Zn, and B. The linear regression model demonstrated high predictive capacity (R2 > 0.85) for the nutrient requirements of N, P, K, Mg, and S in the fruit. Conclusion. Logistic models provided high precision in deterministically modeling nutrient uptake in dragon fruit plants. The study affectively quantified and modeled the nutritional behavior of the plants under Costa Rica’s dry tropical conditions, providing essential information for optimizing fertilization programs for the crop.

Abstract Introduction. Sweet potato (Ipomoea batatas (L) Lam.) is sensitive to weed competition, and chemical control in Costa Rica is challenging due to limited local information on herbicide selectivity. Objective. To determine the selectivity of six herbicides applied at different stages of development to Criollo sweet potatoes and their effect on coverage, biomass, and crop yield. Materials and methods. Between August and December 2021, three experiments were conducted at the Fabio Baudrit Moreno Agricultural Experimental Station, Universidad de Costa Rica, Alajuela, Costa Rica. Herbicides were applied (in kg a.i. ha-1) as follows: a) Experiment 1: 0.36 of metribuzin, 1.50 of pendimethalin, 0.48 of clomazone, 0.075 of halosulfuron, 1.00 of linuron, and 1.25 of metolachlor, applied six days after planting (dap) in a randomized block design with four repetitions; b) Experiment 2: 1.00 of linuron and 0.36 of metribuzin 0.36, applied at -1, 15 and 30 dap, in a randomized block design with a 2x3 factorial arrangement and three repetitions; and c) Experiment 3: 0.075 of halosulfuron and 0.36 of metribuzin, mixed with 0.125 of fluazifop-p-butyl in a randomized block design with three repetitions. Weeding was performed at 15 and 30 dap in all cases. Results. Root yield was not affected in any of the three experiments. Experiment 1: Only halosulfuron caused mild damage to the plants; no herbicide affected above-ground biomass production. Experiment 2: Only linuron and metribuzin applied at 15 and 30 dap caused mild damage. Experiment 3: The mixtures caused temporary damage to the plants. Conclusions. The evaluated herbicides were selective to the Criollo sweet potatoes, and did not affect the yield of marketable storage roots. Only halosulfuron caused mild damage in all application forms, and metribuzin and linuron only in late applications.

Resumen Introducción. El camote (Ipomoea batatas (L) Lam) es sensible a la competencia por arvenses, cuyo control químico en Costa Rica se dificulta por la limitada información local generada sobre selectividad de herbicidas. Objetivo. Determinar la selectividad de seis herbicidas aplicados en diferentes etapas de desarrollo al camote Criollo y su efecto en la cobertura, biomasa y rendimiento del cultivo. Materiales y métodos. Entre agosto y diciembre 2021, se realizaron tres experimentos en la Estación Experimental Agrícola Fabio Baudrit Moreno, Universidad de Costa Rica, Alajuela, Costa Rica. Estos incluyeron la aplicación de herbicidas (en kg i.a. ha-1) de la siguiente manera: a) experimento 1: 0,36 de metribuzin, 1,50 de pendimetalina, 0,48 de clomazone, 0,075 de halosulfuron, 1,00 de linuron y 1,25 de metolaclor, aplicados seis días después de la siembra (dds) en diseño de bloques al azar con cuatro repeticiones; b) experimento 2: 1,00 de linuron y 0,36 de metribuzin, aplicados a los -1, 15 y 30 dds, en diseño de bloques al azar con arreglo factorial 2x3 y tres repeticiones; y c) experimento 3: 0,075 de halosulfuron y 0,36 de metribuzin, mezclado con 0,125 de fluazifop-p-butil en diseño de bloques al azar con tres repeticiones. En todos los casos se realizó deshierba 15 y 30 dds. Resultados. En ninguno de los tres experimentos se vio afectada la producción de raíces reservantes. Experimento 1: solo el halosulfuron causó daños leves en las plantas; ningún herbicida afectó la producción de biomasa aérea. Experimento 2: solo el linuron y metribuzin aplicados 15 y 30 dds causaron daños leves. Experimento 3: las mezclas causaron daños temporales en las plantas. Conclusiones. Los herbicidas evaluados fueron selectivos al camote variedad Criollo y no afectaron el rendimiento de raíces reservantes comercializables; solo halosulfuron causó daños leves en todas las formas de aplicación, y metribuzin y linuron solo en aplicaciones tardías.

Resumo Antecedentes: O aumento da literacia em saúde em pessoas com doenças crónicas é essencial para evitar complicações e promover a tomada de decisões responsável e consciente. Assim, foi desenhada uma ferramenta audiovisual para promover a literacia sobre doença arterial periférica (DAP) em ambiente hospitalar, e foi realizada uma avaliação preliminar da adequação da ferramenta. Material e Métodos: A ferramenta foi desenvolvida por uma equipa multidisciplinar. A avaliação preliminar do estudo de adequação de uma ferramenta audiovisual foi realizada com uma amostra de sete doentes com DAP internados num Serviço de Angiologia e Cirurgia Vascular e com um grupo de quatro profissionais especializados na matéria (literacia em saúde e DAP). A conceção, elaboração e produção da ferramenta audiovisual basearam-se numa revisão de literatura, num grupo focal informal com doentes, num modelo de comunicação e num modelo empírico de mudança comportamental. Através deste estudo preliminar de avaliação de adequação, identificamos as características de adequação desta ferramenta audiovisual, que poderá ser transmitida em salas de espera e no internamento de um departamento de cirurgia vascular. O Teste de Adequação de Informação de Saúde Escrita (TAISE) foi usado por profissionais e doentes para obter diferentes fatores de adequação para cada um dos 11 vídeos. Resultados: A ferramenta audiovisual desenvolvida e criada para doentes com DAP mostrou-se acessível, compreensível e atraente para pessoas com baixos níveis de educação. Os doentes ficaram satisfeitos com a ferramenta audiovisual e destacaram pontos positivos, relatando também algumas sugestões de alterações. Os profissionais de saúde avaliaram os 11 vídeos com um alto nível de adequação variando de 82% a 93.05% de adequação. Dos 19 fatores (do TAISE), a qualidade das ilustrações, a presença de tabelas e listas e a estimulação e o incentivo ao aprendizado foram as duas dimensões pontuadas como menos apropriadas/usadas. Conclusão: A ferramenta audiovisual desenvolvida para melhorar a literacia em saúde sobre a DAP apresentou características preliminares de adequação que a tornam um material de alta qualidade para ser utilizado em futuros estudos de avaliação de eficácia desta ferramenta com esta população.

Abstract Background: Increasing health literacy in people with chronic illness is essential to prevent disease complications and to promote responsible and conscious decision-making. Therefore, an audiovisual tool was developed to promote literacy about peripheral arterial disease (PAD) in a hospital setting, and a preliminary evaluation of the tool’s suitability was carried out. Material and Methods: The tool was developed by a multidisciplinary team. The preliminary assessment of the suitability study of an audiovisual tool was carried out with a sample of 7 patients with PAD admitted to an Angiology and Vascular Surgery Service and with a group of four professionals specialized in the subject (health literacy and PAD). The design, elaboration, and production of the audiovisual tool were based on a literature review, an informal focus group with patients, a communication model, and an empirical model of behavioral change. Through this preliminary suitability assessment study, we identified the suitability characteristics of this audiovisual tool that can be transmitted in waiting rooms and vascular surgery hospitalizations. The Suitable Assessment of Material (SAM) was used by professionals and patients to obtain different appropriateness factors for each of the 11 videos. Results: The audiovisual tool developed and built for patients with PAD proved to be accessible, understandable, and attractive for people with low levels of education. The patients were satisfied with the audiovisual tool and highlighted positive points, also reporting some suggestions for changes. Health professionals evaluated the 11 videos with a high level of adequacy ranging from 82% to 93.05% adequacy. Out of 19 factors (from the SAM), the quality of the illustrations, the presence of tables and lists, and stimulation and incentive to learning were the two dimensions scored as least appropriate/used. Conclusion: The audiovisual tool developed to improve health literacy on PAD presented preliminary suitability characteristics that make it a high-quality material to be used in future studies that evaluate the effectiveness of the tool with this population.