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1.
Sensors (Basel) ; 22(18)2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36146449

RESUMEN

Due to formal academic regulations, the affiliation of the university has been amended, and an "Acknowledgements" section has been added to the original publication [...].

2.
Sensors (Basel) ; 20(21)2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-33121017

RESUMEN

We describe a simulation-based Design Space Exploration procedure (DynDSE) for wearable IoT edge devices that retrieve events from streaming sensor data using context-adaptive pattern recognition algorithms. We provide a formal characterisation of the design space, given a set of system functionalities, components and their parameters. An iterative search evaluates configurations according to a set of requirements in simulations with actual sensor data. The inherent trade-offs embedded in conflicting metrics are explored to find an optimal configuration given the application-specific conditions. Our metrics include retrieval performance, execution time, energy consumption, memory demand, and communication latency. We report a case study for the design of electromyographic-monitoring eyeglasses with applications in automatic dietary monitoring. The design space included two spotting algorithms, and two sampling algorithms, intended for real-time execution on three microcontrollers. DynDSE yielded configurations that balance retrieval performance and resource consumption with an F1 score above 80% at an energy consumption that was 70% below the default, non-optimised configuration. We expect that the DynDSE approach can be applied to find suitable wearable IoT system designs in a variety of sensor-based applications.


Asunto(s)
Vuelo Espacial , Dispositivos Electrónicos Vestibles , Algoritmos , Simulación por Computador , Electromiografía , Anteojos , Humanos
3.
Food Technol Biotechnol ; 57(1): 39-47, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31316275

RESUMEN

Freezing conditions affect fish muscle protein functionality due to its denaturation/aggregation. However, jumbo squid (Dosidicus gigas) muscle protein functionality remains stable even after freezing, probably due to the presence of low-molecular-mass compounds (LMMC) as cryoprotectants. Thus, water-soluble LMMC (<1 kDa) fraction obtained from jumbo squid muscle was evaluated by Fourier transform infrared spectrometry. From its spectra, total carbohydrates, free monosaccharides, free amino acids and ammonium chloride were determined. Cryoprotectant capacity and protein cryostability conferred by LMMC were investigated by differential scanning calorimetry. Fraction partial characterization showed that the main components are free amino acids (18.84 mg/g), carbohydrates (67.1 µg/mg) such as monosaccharides (51.1 µg/mg of glucose, fucose and arabinose in total) and ammonium chloride (220.4 µg/mg). Arginine, sarcosine and taurine were the main amino acids in the fraction. LMMC, at the mass fraction present in jumbo squid muscle, lowered the water freezing point to -1.2 °C, inhibiting recrystallization at 0.66 °C. Significant myofibrillar protein stabilization by LMMC was observed after a freeze-thaw cycle compared to control (muscle after extraction of LMMC), proving the effectiveness on jumbo squid protein muscle cryo- stability. Osmolytes in LMMC fraction inhibited protein denaturation/aggregation and ice recrystallization, maintaining the muscle structure stable under freezing conditions. LMMC conferred protein cryostability even at the very low mass fraction in the muscle.

4.
Int J Spine Surg ; 18(1): 32-36, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-37903540

RESUMEN

INTRODUCTION: Lumbosacral traumatic spondylolisthesis L5-S1 is a rare clinical entity that compromises the stability of the L5 vertebra by displacing it anteriorly, laterally, or posteriorly on the S1 vertebral body secondary to osteotendinous and/or articular compromise of this segment due to trauma. This pathology is difficult to classify and manage; although surgical management remains the gold standard, short- and long-term results in the literature are scarce and highly variable. PATIENT PRESENTATION: We present the case of a 53-year-old patient with lumbar trauma due to a free fall from a height of 6 meters. The fall resulted in cauda equina syndrome secondary to lumbosacral traumatic spondylolisthesis L5-S1, which required immediate surgical management. INTERVENTION AND OUTCOME: For surgical management, we used a posterior approach for L5-S1 transpedicular screw fixation, spinal decompression, bilateral root foraminotomy of L5, and L5-S1 open transforaminal lumbar interbody fusion with open reduction. After the operation, the patient reported immediate improvement of postoperative lower extremities pain and was discharged on the third postoperative day after achieving clinical improvement with physical therapy and bladder rehabilitation exercises. CONCLUSION: Lumbosacral traumatic spondylolisthesis L5-S1 is an unusual pathology that requires further study as there is currently no standardized classification. Surgical management is the gold standard and includes open reduction with short transpedicular screw fixation in segment L5-S1 and other surgical interventions such as extension to the pelvis with iliac screws, screws to the L4 vertebral body, and use of lumbar interbody fusion cages.

5.
Arch Bone Jt Surg ; 12(4): 256-263, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716182

RESUMEN

Objectives: The surgical management of periprosthetic fractures (PPF) and periimplant fractures (PIF) can be challenging. The locking attachment plate (LAP) was proposed in recent years for the osteosynthesis of such fractures. The aim of this study was to assess the experience of a third-level hospital with LAP for the treatment of PPF and PIF, and analyse the clinical outcomes. Methods: Data were prospectively collected and analysed from all patients whose PPF/PIF was treated surgically with LAP in a third-level hospital from June 2018 to June 2022. All fractures were postoperative low-energy femur fractures. The minimum follow-up period was six months. Results: Thirty-eight patients (31 women) met the eligibility criteria. The mean age was 86.3 years. The median time until surgery was 4 days. A mean of 3.61 screws were used for each LAP. The mean femur plate length was 14 holes, and the mean working length 7.1 holes. The median hospital stay was nine days. The mean follow-up was 19.56 months. At one month, 12 patients tolerated partial weight-bearing. Five patients walked independently indoors. One patient had died and seven patients were readmitted. At six months, six more patients had died. Fifteen patients tolerated full weight-bearing (FWB). Nine patients walked independently indoors, six outdoors. Twenty-five patients reached fracture consolidation without malalignment. Nine patients were readmitted. At 12 months, another patient had died. Seventeen patients tolerated FWB. Eleven patients walked independently indoors, six outdoors. Twenty-five patients achieved fracture consolidation without malalignment. Five patients were readmitted. Fourteen patients crossed the two-year postoperative threshold. All achieved fracture consolidation. Two patients passed the 4-year postoperative milestone. Conclusion: The clinical results of patients whose PPF or PIF was treated with the LAP are promising. This fixation method is a viable option to be considered when planning surgery for such fractures.

6.
Fish Physiol Biochem ; 39(2): 121-30, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22752357

RESUMEN

Pterygoplichthys disjunctivus viscera chymotrypsin was purified by fractionation with ammonium sulfate (30-70 % saturation), gel filtration, affinity, and ion exchange chromatography. Chymotrypsin molecular weight was approximately 29 kDa according to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), shown a single band in zymogram. Electrofocusing study suggested being an anionic enzyme (pI ≈ 3.9), exhibiting maximal activity at pH 9 and 50 °C, using Suc-Ala-Ala-Pro-Phe-p-nitroanilide (SAAPNA) as substrate. Enzyme was effectively inhibited by phenyl methyl sulfonyl fluoride (PMSF) (99 %), and N-tosyl-L-phenylalanine chloromethyl ketone (TPCK) (94 %). Enzyme activity was affected by the following ions in decreasing order: Hg(2+), Fe(2+), Cu(2+), Li(1+), Mg(2+), K(1+), Mn(2+), while Ca(2+) had no effect. Chymotrypsin activity decreased continuously as NaCl concentration increased (from 0 to 30 %). K m and V max values were 0.72 ± 1.4 mM and 1.15 ± 0.06 µmol/min/mg of protein, respectively (SAAPNA as substrate). Results suggest the enzyme has a potential application where low processing temperatures are needed, such as in fish sauce production.


Asunto(s)
Bagres/metabolismo , Quimotripsina/aislamiento & purificación , Vísceras/química , Animales , Fraccionamiento Químico , Quimotripsina/metabolismo , Electroforesis en Gel de Poliacrilamida/veterinaria , Concentración de Iones de Hidrógeno , Cinética , Metales Pesados/metabolismo , México , Cloruro de Sodio/metabolismo , Temperatura
7.
PLoS One ; 18(9): e0291264, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37682925

RESUMEN

In coffee (Coffea arabica L.), male sterility is a prerequisite for the exploitation of heterosis since it provides an efficient and reliable method for the production of hybrid seeds. Given its relevance, the objective of this study was to identify male-sterile genotypes within the Colombian Coffee Collection that can be used in genetic improvement. For this purpose, Ethiopian germplasm and progenies derived from hybrids between C. arabica x C. canephora were explored between 2017 and 2021. In the first stage, genotypes without visual presence of pollen were preselected in the field, followed by selection through staining and verification of male sterility and female fertility through directed crosses (directed, reciprocal and selfing). In this stage, 9,753 trees were explored, preselecting 2.4% due to visual absence of pollen. The staining of structures allowed us to confirm the lack or sporadic production of pollen in 23 individuals of Ethiopian origin. The results of the directed crosses led to the identification of 11 male-sterile and 12 partially male-sterile genotypes belonging to 15 accessions. In all cases, the individuals were characterized by the presence of anthers but with an absence or low content of pollen, which is why the male sterility is possibly of the sporogenic type. The female receptivity values were between 2.9% and 72.6%, being higher than 30% in five genotypes. These genotypes are a valuable tool for the genetic improvement of C. arabica with the potential to facilitate the use of heterosis and to allow a deeper understanding the development of male gametophytes in the species.


Asunto(s)
Coffea , Infertilidad Masculina , Rubiaceae , Humanos , Masculino , Coffea/genética , Café , Colombia
8.
Foods ; 12(15)2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37569120

RESUMEN

Knowledge is limited about the level of bioactive compounds and antioxidant activity of seeds from bred lines of common beans developed from interspecific crosses using four different Phaseolus species (P. vulgaris L., P. coccineus L., P. acutifolius A. Gray. Gray., and P. dumosus). In this study, differences in the nutritional quality of seeds among 112 bean genotypes were evaluated by measuring the levels of phenolic compounds, pigments, antioxidant activity, and sugars. The bean genotypes were grown under high temperatures and acid soil conditions in the Amazon region of Colombia. Five typology groups of bean genotypes were identified based on the level of bioactive compounds and their functional capacity: (1) highly bioactive and functional (HBF); (2) moderately bioactive and functional (MBF); (3) moderate antioxidant content with pigment influence (MACP); (4) moderately antinutritional with limited antioxidant potential (MALAP); and (5) antinutritional, low bioactive, and functional (ALBF). We developed a nutritional quality index (NQI) with values ranging from 0 to 1 based on the nutritional and anti-nutritional balance of each genotype and the higher values of the NQI of a genotype indicating greater nutritional quality. We found three interspecific bred lines (SER 212, SER 213, and RRA 81), with NQI values higher than 0.8. These three lines belong to the typology group of HBF. The superior nutritional quality of these three interspecific bred lines is attributed to a greater level of bioactive compounds and antioxidant capacity. These three bred lines may serve as useful parents to develop nutritionally superior and stress-resilient beans from bean breeding programs. Further research is needed to explore the role of testa color in improving the nutritional quality of seeds of common bean genotypes grown under different climatic conditions.

9.
Plants (Basel) ; 12(18)2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37765443

RESUMEN

Many common bean (Phaseolus vulgaris L.) plants cultivated in areas of the world with acidic soils exhibit difficulties adapting to low phosphorus (P) availability, along with aluminum (Al) toxicity, causing yield loss. The objective of this study was to evaluate the influence of an increase in P supply level on the agronomic, phenological, and physiological performance of two common bean breeding lines grown in acidic soil, with low fertility and under high temperature conditions, in a screenhouse. A randomized complete block (RCB) design was used under a factorial arrangement (five levels of P × 2 genotypes) for a total of 10 treatments with four replications. The factors considered in the experiment were: (i) five P supply levels (kg ha-1): four levels of P0, P15, P30, and P45 through the application of rock phosphate (RP), and one P level supplied through the application of organic matter (PSOM) corresponding to 25 kg P ha-1 (P25); and (ii) two advanced bean lines (BFS 10 and SEF10). Both bean lines were grown under the combined stress conditions of high temperatures (day and night maximum temperatures of 42.5 °C/31.1 °C, respectively) and acidic soil. By increasing the supply of P, a significant effect was found, indicating an increase in the growth and development of different vegetative organs, as well as physiological efficiency in photosynthesis and photosynthate remobilization, which resulted in higher grain yield in both bean lines evaluated (BFS 10 and SEF10). The adaptive responses of the two bean lines were found to be related to phenological adjustments (days to flowering and physiological maturity; stomatal development), as well as to heat dissipation strategies in the form of heat (NPQ) or unregulated energy (qN) that contributed to greater agronomic performance. We found that, to some extent, increased P supply alleviated the negative effects of high temperature on the growth and development of the reproductive organs of bean lines. Both bean lines (BFS 10 and SEF 10) showed adaptive attributes suited to the combined stress conditions of high temperature and acidic soil, and these two lines can serve as useful parents in a bean breeding program to develop multiple stress tolerant cultivars.

10.
Food Chem ; 408: 135165, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36527926

RESUMEN

The meat greening is an abnormal pigmentation related to microbiological contamination and lipid oxidation during storage. This color change results from sulfmyoglobin (SulfMb) production promoted by the reaction between metmyoglobin (MetMb), H2O2, and thiol compounds. Spectral studies on cooked meat suggested the production of SulfMb, probably due to the increment of free radicals during thermal treatment. Thus, we evaluated the involvement of free radicals and heme iron in the SulfMb production from horse MetMb and free cysteine (Cys) during thermal treatment. The results confirm that the reaction of SulfMb production at meat muscle pH (5.7-7.2) during heat treatment is a product of free radicals formed from Cys oxidation (SH) and reactive oxygen species (O2-, H2O2). This is catalyzed by the release of heme iron, thus promoting a consecutive reaction having MbFe(IV)O as a reaction intermediate.


Asunto(s)
Cisteína , Peróxido de Hidrógeno , Animales , Caballos , Peróxido de Hidrógeno/química , Mioglobina/química , Metamioglobina/química , Radicales Libres , Oxidación-Reducción , Hierro/química , Hemo
11.
J Agric Food Chem ; 71(46): 17485-17493, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37943570

RESUMEN

Myoglobin is the main factor responsible for muscle pigmentation in tuna; muscle color depends upon changes in the oxidative state of myoglobin. The tuna industry has reported muscle greening after thermal treatment involving metmyoglobin (MetMb), trimethylamine oxide (TMAO), and free cysteine (Cys). It has been proposed that this pigmentation change is due to a disulfide bond between a unique cysteine residue (Cys10) found in tuna MetMb and free Cys. However, no evidence has been given to confirm that this reaction occurs. In this review, new findings about the mechanism of this greening reaction are discussed, showing evidence of how free radicals produced from Cys oxidation under thermal treatment participate in the greening of tuna and horse muscle during thermal treatment. In addition, the reaction conditions are compared to other green myoglobins, such as sulfmyoglobin, verdomyoglobin, and cholemyoglobin.


Asunto(s)
Cisteína , Mioglobina , Animales , Caballos , Mioglobina/química , Cisteína/química , Metamioglobina/química , Oxidación-Reducción , Músculos/metabolismo
12.
Plants (Basel) ; 11(23)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36501322

RESUMEN

Increasing biodiversity in highly diverse plant communities can jointly increase ecosystem function and ecosystem vulnerability. This paradox requires further attention. This study analyzed the functional response of plant communities to above- and below-ground parameters along the chronosequence (degraded pastures (DP), early forests (EF), intermediate forests (IF), and old-growth forests (OF)) in two highly fragmented landscapes of the Colombian Amazon as an estimate of the level of functional vulnerability. Three sets of functional attributes were evaluated: (i) functional composition based on the community-weighted mean (CWM) of five traits; (ii) functional diversity based on the multi-trait indices and functional dispersion (FDis) of each individual trait; and (iii) the functional vulnerability at the community-level and species-level. The individual traits did not show a clear pattern along the chronosequence. However, the trend indicated an increase in the values of resource conservation traits with the age of abandonment. The functional response of the community did not vary between landscapes. Between DP and OF, there was a significant increase in functional diversity and a decrease in functional redundancy, which increased community-level vulnerability. Consequently, the more vulnerable species were observed in the IF and OF plots. In addition, a decrease in environmental parameters, such as penetration resistance, bulk density and Ca content, and an increase in slope, precipitation, electric conductivity, pH, clay, organic material, and P and N contents increased the vulnerability. We elucidated the need for secondary forest management in terms of conservation and restoration to maintain the capacity to respond to changing environmental conditions in highly fragmented landscapes in the Andean-Amazonian transition.

13.
Plants (Basel) ; 11(10)2022 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-35631796

RESUMEN

The evaluation of disease resistance is considered an important aspect of phenotyping for crop improvement. Identification of advanced lines of the common bean with disease resistance contributes to improved grain yields. This study aimed to determine the response of the photosynthetic apparatus to natural pathogen infection by using chlorophyll (Chla) fluorescence parameters and their relationship to the agronomic performance of 59 common bean lines and comparing the photosynthetic responses of naturally infected vs. healthy leaves. The study was conducted over two seasons under acid soil and high temperature conditions in the western Amazon region of Colombia. A disease susceptibility index (DSI) was developed and validated using chlorophyll a (Chla) fluorescence as a tool to identify Mesoamerican and Andean lines of common bean (Phaseolus vulgaris L.) that are resistant to pathogens. A negative effect on the functional status of the photosynthetic apparatus was found with the presence of pathogen infection, a situation that allowed the identification of four typologies based on the DSI values ((i) moderately resistant; (ii) moderately susceptible; (iii) susceptible; and (iv) highly susceptible). Moderately resistant lines, five of them from the Mesoamerican gene pool (ALB 350, SMC 200, BFS 10, SER 16, SMN 27) and one from the Andean gene pool (DAB 295), allocated a higher proportion of energy to photochemical processes, which increased the rate of electron transfer resulting in a lower sensitivity to disease stress. This photosynthetic response was associated with lower values of DSI, which translated into an increase in the accumulation of dry matter accumulation in different plant organs (leaves, stem, pods and roots). Thus, DSI values based on chlorophyll fluorescence response to pathogen infection could serve as a phenotyping tool for evaluating advanced common bean lines. Six common bean lines (ALB 350, BFS 10, DAB 295, SER 16, SMC 200 and SMN 27) were identified as less sensitive to disease stress under field conditions in the western Amazon region of Colombia, and these could serve as useful parents for improving the common bean for multiple stress resistance.

14.
Farm Hosp ; 46(5): 290-295, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-36183229

RESUMEN

OBJECTIVE: Critically ill patients are at increased risk of drug-drug interactions  but their prevalence and clinical relevance remains unclear. The prevalence of  potential drug-drug interactions in an intensive care unit according to  Micromedex Drug-Reax® and Lexi-Interact® databases was studied and the  concordance between the two databases was assessed. In addition, drug-drug  interactions detected in 2013 were compared with those identified in 2018 to  determine updates between these years. METHOD: Between January and June 2013, 152 critical care patients were  prospectively included. Cardiac patients were excluded. Demographic and  clinical data together with the drugs administered on the first calendar day of  intensive care unit admission were recorded. Potential drug-drug interactions  were searched in both Drug-Reax® and Lexi-Interact ® and their prevalence,  level of severity and evidence were compared considering the same sample in  2013 and 2018. RESULTS: In 2013, 1,025 potential drug-drug interactions were identified, corresponding to 438 unique pairs. Lexi-Interact® identified more  interactions (92.8%) than Drug-Reax® (34.0%). The percentage of agreement between databases was 27.4%. The number of interactions  included in both databases increased after the five years but their level of  evidence   decreased. The most common potential drug-drug interactions involved sedatives and analgesics, intentionally prescribed concomitantly. Only two potential drug-drug interactions were classified as contraindicated by both  databases. None of the potential drug-drug interactions identified had a  noticeable clinical impact. Neither did they imply a prescription change. CONCLUSIONS: This study shows that the prevalence of potential drugdrug interactions in the intensive care unit is high, although their clinical relevance is generally low. Our data also show a lack of concordance between Drug-Reax® and Lexi-Interact®, as well as their  updates.


OBJETIVO: Los pacientes críticos presentan un mayor riesgo de interacciones farmacológicas, aunque su prevalencia y relevancia clínica siguen  sin estar claras. En el presente estudio se analizó la prevalencia de  interacciones farmacológicas potenciales en una unidad de cuidados intensivos  mediante las bases de datos Micromedex Drug-Reax® y Lexi-Interact® y se  evaluó la concordancia entre ambas bases de datos. También se compararon  las interacciones farmacológicas detectadas en 2013 con las identificadas en  2018 para evaluar las actualizaciones realizadas durante este periodo de  tiempo. Método: Entre enero y junio de 2013 se incluyeron de forma prospectiva 152  pacientes críticos. Los pacientes cardiacos fueron excluidos. Se registraron los  datos demográficos y clínicos junto con los fármacos administrados durante el  primer día de ingreso en la unidad de cuidados intensivos. Las interacciones se  buscaron tanto en Micromedex Drug-Reax® como en Lexi-Interact® y se  comparó su prevalencia, el nivel de severidad y la evidencia considerando la  misma muestra en 2013 y 2018. Resultados: En 2013 se identificaron 1.025 interacciones farmacológicas potenciales, correspondientes a 438 pares únicos. Lexi- Interact® identificó más interacciones (92,8%) que Drug-Reax® (34,0%). El  porcentaje de concordancia entre las dos bases de datos fue del 27,4%. El  número de interacciones incluidas en ambas bases de datos aumentó durante  los cinco años, pero su nivel de evidencia disminuyó. Las interacciones  farmacológicas potenciales más comunes incluyeron sedantes y analgésicos,  rescritos intencionadamente de forma concomitante. Sólo dos interacciones farmacológicas potenciales fueron clasificadas como contraindicadas por ambas  bases de datos. Ninguna de las interacciones identificadas tuvo un impacto clínico notable ni supuso un cambio de prescripción. CONCLUSIONES: ste estudio muestra que la prevalencia de interacciones farmacológicas potenciales en las unidades de cuidados intensivos es alta,  aunque su relevancia clínica es generalmente baja. Nuestros datos también  muestran la falta de concordancia entre Drug-Reax® y Lexi- Interact®, así  como sus actualizaciones.


Asunto(s)
Cuidados Críticos , Unidades de Cuidados Intensivos , Bases de Datos Factuales , Interacciones Farmacológicas , Humanos , Hipnóticos y Sedantes
15.
Plants (Basel) ; 11(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36501276

RESUMEN

Disease stress caused by plant pathogens impacts the functioning of the photosynthetic apparatus, and the symptoms caused by the degree of severity of the disease can generally be observed in different plant parts. The accurate assessment of plant symptoms can be used as a proxy indicator for managing disease incidence, estimating yield loss, and developing genotypes with disease resistance. The objective of this work was to determine the response of the photosynthetic apparatus to the increased disease severity caused by web blight Thanatephorus cucumeris (Frank) Donk on the common bean (Phaseolus vulgaris L.) leaves under acidic soil and the humid tropical conditions of the Colombian Amazon. Differences in chlorophyll fluorescence parameters, including Fv/Fm, Y(II), Y(NPQ), Y(NO), ETR, qP, and qN in leaves with different levels of severity of web blight in an elite line (BFS 10) of common bean were evaluated under field conditions. A significant effect of web blight on the photosynthetic apparatus was found. A reduction of up to 50% of energy use dedicated to the photosynthetic machinery was observed, even at the severity scale score of 2 (5% surface incidence). The results from this study indicate that the use of fluorescence imaging not only allows for the quantifying of the impact of web blight on photosynthetic performance, but also for detecting the incidence of disease earlier, before severe symptoms occur on the leaves.

16.
PLoS One ; 16(12): e0261612, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34965264

RESUMEN

Trees dispersed in grazing areas are contribute to the sustainability of livestock systems. The interactions between trees and soil are ecological processes that allow the modification of the biology, fertility, and physics of the soil. This study was aimed to assess the influence of dispersed trees in pastures on soil properties in grazing areas for dual-purpose cattle systems in the Piedmont region of the Colombian Amazon. The work was done in grazing areas with scattered trees at the Centro de Investigaciones Amazónicas CIMAZ-Macagual in Florencia-Caquetá-Colombia. We evaluated the effect of five tree species, Andira inermis, Bellucia pentámera, Guarea Guidonia, Psidium guajava and Zygia longifolia, on soil properties (up to 30 cm soil depth) under and outside the influence of the crown. Under the tree crown, three points were systematically taken in different cardinal positions. This was done at a distance corresponding to half the radius of the tree crown. The sampling points in the open pasture area (out of crown) were made in the same way, but at 15 m from the crown border. The ANOVA showed significant interaction (P < 0.0001) between tree species and location for macrofauna abundance up to 30 cm soil depth. For this reason, we performed the comparison between locations for each tree species. Chemical soil variables up to 10 cm soil depth only showed interaction of tree species-location for exchangeable potassium (P = 0.0004). Soil physical soil characteristics up to 30 cm soil depth only showed interaction of tree species-location at 20 cm soil depth (P = 0.0003). The principal component analysis for soil properties explained 61.1% of the total variability of the data with the two first axes. Using Monte Carlo test, we found crown effect for all species. Trees help to control exchangeable mineral elements that can affect the soil, potentiate basic cations such as magnesium and potassium, increase the abundance of soil macrofauna; but some trees with high ground level of shade in grazing areas could increase soil compaction due to the greater concentration of cattle in these areas.


Asunto(s)
Agricultura/métodos , Pradera , Suelo/química , Árboles , Animales , Bovinos , Colombia , Conservación de los Recursos Naturales
17.
Plants (Basel) ; 10(11)2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34834685

RESUMEN

The objective of this study was to evaluate photosynthetic performance based on gas exchange traits, chlorophyll a fluorescence, and leaf water potential (ΨL) in nine Hevea brasiliensis genotypes from the ECC-1 (Élite Caquetá Colombia) selection and the cultivar IAN 873 (control) in response to different climatic (semi-humid warm and humid warm climates), seasonal (dry and rainy periods), and hourly (3:00 to 18:00) variations that can generate stress in the early growth stage (two-year-old plants) in two large-scale clonal trials in the Colombian Amazon. The photosynthetic performance in 60% of the Colombian genotypes was slightly affected under the conditions with less water availability (dry period, semi-humid warm site, and between 9:00 and 15:00 h), as compared with IAN 873, whose affectation was moderate in terms of photosynthesis rates, but its water conservation strategy was strongly affected. The ECC 90, ECC 83, and ECC 73 genotypes had the best photosynthetic performance under conditions of greater water limitation, and ECC 35, and ECC 64 had a higher water status based on the leaf water potential, with intermediate photosynthetic performance. This germplasm has a high potential for selection in rubber tree breeding programs in future scenarios of climate change in the Colombian Amazon.

18.
Plants (Basel) ; 11(1)2021 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35009119

RESUMEN

Common bean (Phaseolus vulgaris L.) is sensitive to different types of abiotic stresses (drought, high temperature, low soil fertility, and acid soil), and this may limit its adaptation and consequently to its yield under stress. Because of this, a sister species, tepary bean (Phaseolus acutifolius A. Gray), has recently gained attention in breeding for improved abiotic stress tolerance in common bean. In this study, we evaluated the adaptation of 302 accessions of tepary bean (Phaseolus acutifolius A. Gray) and its wild relatives (grouped in four types of tepary bean genetic resource: cultivated, acutifolius regressive, acutifolius wild, tenuifolius wild) when grown under high temperature and acid soil conditions with aluminum toxicity in the Amazon region of Colombia. Our objective was to determine differences among four types of tepary bean genetic resource in their morpho-phenological, agronomic, and physiological responses to combined high temperature and acid soil stress conditions. We found that cultivated P. acutifolius var acutifolius presented a greater number of pods per plant, as well as larger seeds and a greater number of seeds per pod. Some traits, such as root biomass, days to flowering and physiological maturity, specific leaf area, and stomatal density, showed significant differences between types of tepary bean genetic resource, probably contributing to difference in adaptation to combined stress conditions of high temperature and acid soil conditions. The photochemical quenching (qP) was higher in cultivated P. acutifolius var. acutifolius, while energy dissipation by non-photochemical quenching (NPQ) in the form of heat and the coefficient of non-photochemical dissipation (qN) were higher in acutifolius regressive and tenuifolius wild accessions. We have identified 6 accessions of cultivated and 19 accessions of tenuifolius wild that exhibited grain yields above 1800 kg ha-1. These accessions could be suitable to use as parents to improve dry seed production of tepary bean under combined stress conditions of high temperature and acid soil.

19.
PLoS One ; 16(1): e0245971, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33493228

RESUMEN

This paper studies the influence of community capitals on well-being through a Community Capital Index (CCI) within coffee-growing families in southern Colombia. Our results show different farm typologies, with different levels of capital endowment translated into well-being that, in our case, were represented in the CCI. Specifically, social and political capitals positively affect coffee-growing families' decisions in terms of life strategies. The results of this study increase our understanding of welfare enhancement and its relationship with capital endowment according to the type of coffee producer, having implications for the planning of more effective programs towards the improvement of quality of life.


Asunto(s)
Composición Familiar , Calidad de Vida , Capital Social , Café , Colombia , Humanos , Características de la Residencia
20.
Plants (Basel) ; 10(11)2021 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-34834775

RESUMEN

Knowledge of the physiological basis for improved genetic adaptation of common bean (Phaseolus vulgaris L.) lines to acid soils and high temperature conditions in the Amazon region of Colombia is limited. In this study, we evaluated the differences among 41 common bean lines in energy use, leaf cooling, photosynthate partitioning to pod formation and grain filling, and grain yield over two seasons under acid soil and high temperature stress in the Amazon region of Colombia. Common bean lines evaluated included medium and large seeded interspecific lines of Mesoamerican and Andean gene pools with different levels of adaptation to abiotic stress conditions and some lines are improved for iron and zinc (biofortified) concentration in seeds. We found three bean lines (GGR 147, SMG 21 and SMG 12) that were superior in their photosynthetic response, leaf cooling, photosynthate partitioning ability to pod formation and grain filling, resulting in grain yields exceeding 1900 kg ha-1 under acid soil and high temperature stress conditions. The superior photosynthetic performance was attributed to the efficient use of absorbed energy on the electron level in thylakoids, which is mainly oriented to a higher quantum yield of PSII (ΦII), lower energy dissipation in the form of heat (ΦNPQ), high linear electron flow (LEF) and high fraction of PSI centers in open state (PSIopen). We speculate that these photosynthetic and photosynthate partitioning responses of superior bean lines are part of the genetic adaptation to acidic soils and high temperature stress conditions. Among the evaluated bean lines, three lines (GGR 147, SMG 21 and SMG 12) combined the desirable attributes for genetic improvement of stress tolerance and biofortification. These lines can serve as parents to further improve traits (energy use efficiency and multiple stress resistance) that are important for bean production in the Amazon region.

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