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1.
Proc Natl Acad Sci U S A ; 120(10): e2214035120, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36848574

RESUMEN

Assessing environmental changes in Southern Ocean ecosystems is difficult due to its remoteness and data sparsity. Monitoring marine predators that respond rapidly to environmental variation may enable us to track anthropogenic effects on ecosystems. Yet, many long-term datasets of marine predators are incomplete because they are spatially constrained and/or track ecosystems already modified by industrial fishing and whaling in the latter half of the 20th century. Here, we assess the contemporary offshore distribution of a wide-ranging marine predator, the southern right whale (SRW, Eubalaena australis), that forages on copepods and krill from ~30°S to the Antarctic ice edge (>60°S). We analyzed carbon and nitrogen isotope values of 1,002 skin samples from six genetically distinct SRW populations using a customized assignment approach that accounts for temporal and spatial variation in the Southern Ocean phytoplankton isoscape. Over the past three decades, SRWs increased their use of mid-latitude foraging grounds in the south Atlantic and southwest (SW) Indian oceans in the late austral summer and autumn and slightly increased their use of high-latitude (>60°S) foraging grounds in the SW Pacific, coincident with observed changes in prey distribution and abundance on a circumpolar scale. Comparing foraging assignments with whaling records since the 18th century showed remarkable stability in use of mid-latitude foraging areas. We attribute this consistency across four centuries to the physical stability of ocean fronts and resulting productivity in mid-latitude ecosystems of the Southern Ocean compared with polar regions that may be more influenced by recent climate change.


Asunto(s)
Cambio Climático , Ecosistema , Animales , Regiones Antárticas , Efectos Antropogénicos , Océano Índico
2.
Sensors (Basel) ; 23(14)2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37514799

RESUMEN

Improving soybean (Glycine max L. (Merr.)) yield is crucial for strengthening national food security. Predicting soybean yield is essential to maximize the potential of crop varieties. Non-destructive methods are needed to estimate yield before crop maturity. Various approaches, including the pod-count method, have been used to predict soybean yield, but they often face issues with the crop background color. To address this challenge, we explored the application of a depth camera to real-time filtering of RGB images, aiming to enhance the performance of the pod-counting classification model. Additionally, this study aimed to compare object detection models (YOLOV7 and YOLOv7-E6E) and select the most suitable deep learning (DL) model for counting soybean pods. After identifying the best architecture, we conducted a comparative analysis of the model's performance by training the DL model with and without background removal from images. Results demonstrated that removing the background using a depth camera improved YOLOv7's pod detection performance by 10.2% precision, 16.4% recall, 13.8% mAP@50, and 17.7% mAP@0.5:0.95 score compared to when the background was present. Using a depth camera and the YOLOv7 algorithm for pod detection and counting yielded a mAP@0.5 of 93.4% and mAP@0.5:0.95 of 83.9%. These results indicated a significant improvement in the DL model's performance when the background was segmented, and a reasonably larger dataset was used to train YOLOv7.


Asunto(s)
Glycine max , Fitomejoramiento
3.
High Educ (Dordr) ; 83(6): 1389-1408, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34493877

RESUMEN

The COVID-19 pandemic brought about a global crisis affecting all sectors of society. Higher education is no exception. The closure of higher education institutions has dictated a sudden and unexpected transition from face-to-face to remote teaching to mitigate the spread of the SARS-CoV-2. This paper draws upon a wider piece of research which aimed to understand how higher education students adapted to the closure of their institution and how they looked at their experience of online teaching and learning. In total, 2718 students from different Portuguese higher education institutions participated in the study. Findings showed that both personal and contextual factors explained students' positive or negative adaptation to online teaching and learning as a result of the closure of higher education institutions. Institutional and pedagogical responses, individual self-regulatory and socio-emotional competencies and adequate resources were factors that led to either a more positive or negative student experience of online teaching and learning in times of COVID-19.

4.
J Hered ; 111(3): 263-276, 2020 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32347944

RESUMEN

As species recover from exploitation, continued assessments of connectivity and population structure are warranted to provide information for conservation and management. This is particularly true in species with high dispersal capacity, such as migratory whales, where patterns of connectivity could change rapidly. Here we build on a previous long-term, large-scale collaboration on southern right whales (Eubalaena australis) to combine new (nnew) and published (npub) mitochondrial (mtDNA) and microsatellite genetic data from all major wintering grounds and, uniquely, the South Georgia (Islas Georgias del Sur: SG) feeding grounds. Specifically, we include data from Argentina (npub mtDNA/microsatellite = 208/46), Brazil (nnew mtDNA/microsatellite = 50/50), South Africa (nnew mtDNA/microsatellite = 66/77, npub mtDNA/microsatellite = 350/47), Chile-Peru (nnew mtDNA/microsatellite = 1/1), the Indo-Pacific (npub mtDNA/microsatellite = 769/126), and SG (npub mtDNA/microsatellite = 8/0, nnew mtDNA/microsatellite = 3/11) to investigate the position of previously unstudied habitats in the migratory network: Brazil, SG, and Chile-Peru. These new genetic data show connectivity between Brazil and Argentina, exemplified by weak genetic differentiation and the movement of 1 genetically identified individual between the South American grounds. The single sample from Chile-Peru had an mtDNA haplotype previously only observed in the Indo-Pacific and had a nuclear genotype that appeared admixed between the Indo-Pacific and South Atlantic, based on genetic clustering and assignment algorithms. The SG samples were clearly South Atlantic and were more similar to the South American than the South African wintering grounds. This study highlights how international collaborations are critical to provide context for emerging or recovering regions, like the SG feeding ground, as well as those that remain critically endangered, such as Chile-Peru.


Asunto(s)
Variación Genética , Ballenas/genética , Distribución Animal , Migración Animal , Animales , Brasil , Chile , Conducta Alimentaria , Femenino , Técnicas de Genotipaje , Islas , Masculino , Perú
5.
J Acoust Soc Am ; 147(6): EL498, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32611191

RESUMEN

This study investigated the repertoire, call-type variability and call rates of southern right whales on a calving ground off Brazil in the western South Atlantic. Acoustic tag data were collected from four lactating females and one juvenile. Pulsive, hybrid, and upcalls showed the greatest variability among call-types with up to 23% of non-standard forms detected. Quiet sounds (grunt, single, and double pulse) were detected for the first time in this species on the calving grounds. Although the sample size was limited, results suggest that social interaction increased call-type diversity and call rates, in line with other acoustic studies on right whales.


Asunto(s)
Lactancia , Ballenas , Acústica , Animales , Brasil , Comunicación , Femenino
6.
Knee Surg Sports Traumatol Arthrosc ; 28(2): 389-397, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31250058

RESUMEN

PURPOSE: To evaluate the reliability of an instrumented patellofemoral (PF) stress-testing-the Porto Patellofemoral Testing Device (PPTD)-and validate the instrumented assessment method comparing to manual physical examination. METHODS: Eight asymptomatic volunteers underwent bilateral PF-instrumented examination with the PPTD and magnetic resonance imaging (MRI) to assess intra-rater reliability of the instrumented assessment methodology. Six patients with unilateral PF instability underwent physical examination and PPTD concomitantly with MRI. Manual examination was performed by two blinded surgeons and compared with PPTD test. Ligament stiffness was calculated and compared between injured and non-injured lower limbs. RESULTS: PPTD showed a pre-determined and reproducible stress-force application with excellent intra-rater agreement (intra-class correlation coefficient 0.83-0.98). The manual exam was imprecise with variable examiner-dependent stress-force application. The PPTD resulted in greater lateral patellar translation (converted in quadrants) than manual exam for patients that have reached maximum translation force. Measurement of patellar position and displacement using PPTD was more accurate and precise than the visual estimation of translated quadrants by manual exam. Ligament stiffness curves showed no relevant changes in patellar displacement after 62 N. CONCLUSION: The PPTD instrumented stress-testing is a valid device to quantify PF position and displacement with high intra-rater reliability, showing more accuracy, more precision and less variability than physical examination. This device provides an accurate and objective measure to quantify the patellar movement which can augment the physical examination procedures and assist clinicians in the management of decision-making and in the assessment of post-treatment outcomes of PF pathological conditions.


Asunto(s)
Prueba de Esfuerzo/instrumentación , Inestabilidad de la Articulación/diagnóstico , Luxación de la Rótula/diagnóstico , Adolescente , Adulto , Prueba de Esfuerzo/métodos , Femenino , Humanos , Inestabilidad de la Articulación/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Luxación de la Rótula/diagnóstico por imagen , Examen Físico/métodos , Reproducibilidad de los Resultados , Adulto Joven
7.
Knee Surg Sports Traumatol Arthrosc ; 28(2): 454-462, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31375878

RESUMEN

PURPOSE: To objectively compare side-to-side patellar position and mobility in patients with idiopathic unilateral anterior knee pain (AKP) using a stress-testing device concomitantly with magnetic resonance imaging. It is hypothesized that the painful knees present greater patellar mobility than the contralateral non-painful knees. METHODS: From a total sample of 359 patients, 23 patients with idiopathic unilateral AKP (30.9 years, 23.4 kg/m2, 43% males) were included within the present study. Both knees of all the patients were examined by conventional imaging, including the measurement of trochlear sulcus angle, Caton-Deschamps index, tibial tuberosity to trochlear groove distance, patellar tilt angle and patellar subluxation (both at rest and upon quadriceps contraction). Additionally, the same patients underwent stress testing (Porto Patella Testing Device); these measurements were taken with the patella at rest, after lateral patellar translation and after lateral patellar tilt. Clinical and functional outcomes were obtained using physical examination and the Kujala and Lysholm scores. RESULTS: Painful knees showed statistically significant higher patellar lateral position after stressed lateral translation than non-painful knees (p = 0.028), 9.8 ± 3.6 mm and 7.1 ± 6.3 mm, respectively. The adjusted multivariate logistic model identified the patellar position after lateral displacement to be significantly associated with AKP (OR = 1.165) and the model (AUC = 0.807, p < 0.001) showed reasonable sensitivity (67%) and specificity (73%). CONCLUSION: Patients with idiopathic unilateral AKP with morphologically equivalent knees showed statistically significant increased patellar lateral position after stressed lateral displacement in their painful knee. The greater lateral patellar mobility quantified by the PPTD testing brings more objectivity to the diagnosis. LEVEL OF EVIDENCE: II.


Asunto(s)
Artralgia/fisiopatología , Desviación Ósea/fisiopatología , Inestabilidad de la Articulación/fisiopatología , Articulación Patelofemoral/fisiopatología , Adulto , Artralgia/diagnóstico , Artralgia/diagnóstico por imagen , Artralgia/etiología , Desviación Ósea/diagnóstico , Desviación Ósea/diagnóstico por imagen , Desviación Ósea/etiología , Femenino , Humanos , Inestabilidad de la Articulación/complicaciones , Inestabilidad de la Articulación/diagnóstico , Inestabilidad de la Articulación/diagnóstico por imagen , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/fisiopatología , Imagen por Resonancia Magnética , Masculino , Movimiento , Articulación Patelofemoral/diagnóstico por imagen , Rango del Movimiento Articular , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Adulto Joven
8.
BMC Genomics ; 20(1): 968, 2019 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-31829136

RESUMEN

BACKGROUND: The time required to analyse RNA-seq data varies considerably, due to discrete steps for computational assembly, quantification of gene expression and splicing analysis. Recent fast non-alignment tools such as Kallisto and Salmon overcome these problems, but these tools require a high quality, comprehensive reference transcripts dataset (RTD), which are rarely available in plants. RESULTS: A high-quality, non-redundant barley gene RTD and database (Barley Reference Transcripts - BaRTv1.0) has been generated. BaRTv1.0, was constructed from a range of tissues, cultivars and abiotic treatments and transcripts assembled and aligned to the barley cv. Morex reference genome (Mascher et al. Nature; 544: 427-433, 2017). Full-length cDNAs from the barley variety Haruna nijo (Matsumoto et al. Plant Physiol; 156: 20-28, 2011) determined transcript coverage, and high-resolution RT-PCR validated alternatively spliced (AS) transcripts of 86 genes in five different organs and tissue. These methods were used as benchmarks to select an optimal barley RTD. BaRTv1.0-Quantification of Alternatively Spliced Isoforms (QUASI) was also made to overcome inaccurate quantification due to variation in 5' and 3' UTR ends of transcripts. BaRTv1.0-QUASI was used for accurate transcript quantification of RNA-seq data of five barley organs/tissues. This analysis identified 20,972 significant differentially expressed genes, 2791 differentially alternatively spliced genes and 2768 transcripts with differential transcript usage. CONCLUSION: A high confidence barley reference transcript dataset consisting of 60,444 genes with 177,240 transcripts has been generated. Compared to current barley transcripts, BaRTv1.0 transcripts are generally longer, have less fragmentation and improved gene models that are well supported by splice junction reads. Precise transcript quantification using BaRTv1.0 allows routine analysis of gene expression and AS.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Hordeum/genética , Proteínas de Plantas/genética , Empalme Alternativo , Bases de Datos Genéticas , Regulación de la Expresión Génica de las Plantas , Análisis de Secuencia de ARN , Secuenciación del Exoma
9.
Knee Surg Sports Traumatol Arthrosc ; 27(3): 745-757, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29974174

RESUMEN

PURPOSE: Summarize the in vivo instrumented-assisted patellofemoral evaluation methods for quantifying the patellar mobility in response to a known external force. METHODS: A systematic review using PubMed, EMBASE, Cochrane Library, and SPORTDiscus electronic databases was conducted to search for studies reporting in vivo instrumented-assisted patellofemoral evaluation of patellar mobility. Searches were conducted in duplicate up to October 2017. Methodologic quality of included articles was assessed using a modified version of the Critical Appraisal Skills Program (CASP) critical appraisal tool. RESULTS: From the original 2614 records, 9 studies comprising 568 individuals (24 ± 4.8 years old, 51.4% females)-355 (62.5%) asymptomatic individuals, 87 (15.3%) patellofemoral pain, and 126 (22.2%) patellofemoral instability patients-were included. The average maximum force applied by the instruments to the patella was 38.9 ± 27.7 N (range 11.25 to 80 N). Patellar displacement ranged from 3.9 to 10.4 mm, medially, and 3.5 to 14.8 mm, laterally, for asymptomatic individuals. For patellofemoral instability patients, these values were higher, ranging from 3.8 to 22.1 mm, medially, and 7.0 to 21.9 mm, laterally, being these mean values similar across the instability subgroups (medial, lateral, or multidirectional). Patellofemoral pain had a mean of 10 mm and 10.9 mm for medial and lateral displacements, respectively. Mean methodological quality score was 9.8 ± 2.6 (range 6-13) out of 18 possible points. CONCLUSIONS: There is high heterogeneity within the available instrumented assessment methods and respective measurement outcomes, highlighting the need for better methodological standardization and further developments in this field. This would allow a more accurate and reliable quantification of patellar movement and, subsequently, improve diagnosis, and refine treatment. LEVEL OF EVIDENCE: Systematic review of level II-IV studies, Level IV.


Asunto(s)
Inestabilidad de la Articulación/diagnóstico , Articulación Patelofemoral/fisiología , Rango del Movimiento Articular/fisiología , Estrés Fisiológico , Adolescente , Adulto , Anciano , Niño , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
10.
J Prosthet Dent ; 119(5): 862.e1-862.e7, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29475754

RESUMEN

STATEMENT OF PROBLEM: Interim restorations are occasionally left in the mouth for extended periods and are susceptible to bacterial infiltration. Thus, dental interim cements with antibacterial properties are required. PURPOSE: The purpose of this in vitro study was to determine in vitro antibacterial activity against Streptococcus mutans and to compare the diametrical tensile strength (DTSs) of dental interim cement modified with zinc oxide nanoparticles (ZnO-NPs) with that of cement modified with terpenes. MATERIAL AND METHODS: Antibacterial properties of ZnO-NPs, terpenes, and dental interim cement modified with ZnO-NPs and cement modified with terpenes against S mutans were tested according to minimum inhibitory concentration (MIC) and direct contact inhibition (DCI). Tensile strength levels were evaluated using DTS. Results were analyzed using the Kolmogorov-Smirnov, ANOVA, and Tamhane tests (α=.05). RESULTS: The MICs of ZnO-NPs and terpenes against S mutans were 61.94 µg/g and 0.25% v/v, respectively. The DCI assay under the cylinders of cement (area of contact with the agar surface) revealed significant bacterial growth inhibition on Temp-Bond NE specimens with ZnO-NPs at MIC of 495.2 µg/g (8× MIC) and with terpenes at MIC 0.999% v/v (4× MIC) (P<.05). The Temp-Bond NE cement cylinder (control group) showed the lowest DTS (1.05 ±0.27 MPa) of all other test groups. In the Zn-NPs group, the greatest increase occurred in the NP8 (8× MIC; 495.2 µg/g) group with a value of 1.50 ±0.23 MPa, a significant increase in DTS compared with the control and terpene groups (P<.05). In the terpene group, the highest increase corresponded to group T2 (2× MIC; 0.4995% v/v) with a value of 1.29 ±0.18 MPa. CONCLUSIONS: The addition of terpenes and ZnO-NPs to interim cement showed antibacterial activity when in contact with S. mutans ATCC 25175. Both terpenes and ZnO-NPs antimicrobial agents increased diametral tensile strength.


Asunto(s)
Antibacterianos/farmacología , Cementos Dentales/farmacología , Streptococcus mutans/efectos de los fármacos , Terpenos/farmacología , Óxido de Zinc/farmacología , Técnicas In Vitro , Ensayo de Materiales , Pruebas de Sensibilidad Microbiana , Nanopartículas , Propiedades de Superficie , Resistencia a la Tracción
11.
Plant J ; 87(4): 335-42, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27122470

RESUMEN

Ajmaline biosynthesis in Rauvolfia serpentina has been one of the most studied monoterpenoid indole alkaloid (MIA) pathways within the plant family Apocynaceae. Detailed molecular and biochemical information on most of the steps involved in the pathway has been generated over the last 30 years. Here we report the identification, molecular cloning and functional expression in Escherichia coli of two R. serpentinacDNAs that are part of a recently discovered γ-tocopherol-like N-methyltransferase (γ-TLMT) family and are involved in indole and side-chain N-methylation of ajmaline. Recombinant proteins showed remarkable substrate specificity for molecules with an ajmalan-type backbone and strict regiospecific N-methylation. Furthermore, N-methyltransferase gene transcripts and enzyme activity were enriched in R. serpentina roots which correlated with accumulation of ajmaline alkaloid. This study elucidates the final step in the ajmaline biosynthetic pathway and describes the enzyme responsible for the formation of Nß -methylajmaline, an unusual charged MIA found in R. serpentina.


Asunto(s)
Ajmalina/biosíntesis , Metiltransferasas/metabolismo , Rauwolfia/enzimología , Alcaloides de Triptamina Secologanina/metabolismo , Ajmalina/química , Vías Biosintéticas , Clonación Molecular , Biología Computacional , Metiltransferasas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/química , Raíces de Plantas/enzimología , Raíces de Plantas/genética , Rauwolfia/química , Rauwolfia/genética , Proteínas Recombinantes , Alcaloides de Triptamina Secologanina/química , Especificidad por Sustrato
12.
Adv Exp Med Biol ; 875: 809-13, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26611036

RESUMEN

This study investigates the role of behavioral plasticity in the variation of sound production of southern right whales (Eubalaena australis) in response to changes in the ambient background noise conditions. Data were collected from southern right whales in Brazilian waters in October and November 2011. The goal of this study was to quantify differences in right whale vocalizations recorded in low background noise as a control, fish chorus noise, and vessel noise. Variation in call parameters were detected among the three background noise conditions and have implications for future studies of noise effects on whale sound production.


Asunto(s)
Peces/fisiología , Ruido , Vocalización Animal/fisiología , Ballenas/fisiología , Animales , Humanos
13.
J Acoust Soc Am ; 140(3): 1850, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27914379

RESUMEN

Aiming to gather information on southern right whale (Eubalaena australis) mother-calf pairs' vocal behavior, archival acoustic recorders were deployed at a calving area off Brazil. Manual inspection of spectrograms revealed seven call classes: upcall, downcall, down-upcall, tonal variable, tonal constant, hybrid, and pulsive calls, which are consistent with those previously described for this species in Argentina. Gunshots and warbles, vocalizations described from other right whale species, were not detected. Mean values of start, end, maximum, minimum and peak frequencies, frequency bandwidth and duration were calculated for each call class. Start and end frequencies, frequency bandwidth and duration of upcalls recorded off Brazil were compared to those from other right whale populations and species. Only mean duration of upcalls from Brazil were significantly different from upcalls from all other populations. Differences in call duration may be driven by differences in demographic factors or background noise features among study areas. The repertoire characterization presented in this study will contribute to increase the utility of passive acoustic monitoring as a tool for conservation and research of southern right whales off Brazil as it provides important baseline information on the vocal behavior of this species.


Asunto(s)
Ballenas , Acústica , Animales , Brasil , Femenino , Madres , Ruido , Vocalización Animal
15.
Sci Rep ; 13(1): 6548, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37085558

RESUMEN

Currently, applying uniform distribution of chemical herbicide through a sprayer without considering the spatial distribution information of crops and weeds is the most common method of controlling weeds in commercial agricultural production system. This kind of weed management practice lead to excessive amounts of chemical herbicides being applied in a given field. The objective of this study was to perform site-specific weed control (SSWC) in a corn field by: (1) using a unmanned aerial system (UAS) to map the spatial distribution information of weeds in the field; (2) creating a prescription map based on the weed distribution map, and (3) spraying the field using the prescription map and a commercial size sprayer. In this study, we assumed that plants growing outside the corn rows are weeds and they need to be controlled. The first step in implementing such an approach is identifying the corn rows. For that, we are proposing a Crop Row Identification algorithm, a computer vision algorithm that identifies corn rows on UAS imagery. After being identified, the corn rows were then removed from the imagery and remaining vegetation fraction was classified as weeds. Based on that information, a grid-based weed prescription map was created and the weed control application was implemented through a commercial-size sprayer. The decision of spraying herbicides on a particular grid was based on the presence of weeds in that grid cell. All the grids that contained at least one weed were sprayed, while the grids free of weeds were not. Using our SSWC approach, we were able to save 26.2% of the acreage from being sprayed with herbicide compared to the current method. This study presents a full workflow from UAS image collection to field weed control implementation using a commercial size sprayer, and it shows that some level of savings can potentially be obtained even in a situation with high weed infestation, which might provide an opportunity to reduce chemical usage in corn production systems.

16.
Phytochemistry ; 201: 113266, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35671807

RESUMEN

The biosynthesis of monoterpenoid indole alkaloids in Catharanthus roseus has been most extensively studied, leading to the detailed characterization of the pathway for the formation of their well-known anticancer alkaloids. The present study describes the identification, molecular cloning, and functional expression of C. roseus perivine-Nß-methyltransferase (PeNMT) that converts perivine to Nß-methylperivine (vobasine). PeNMT is member of a recently discovered γ-tocopherol-like N-methyltransferase (γ-TLMT) gene family that displays high substrate specificity and that appears to have evolved in the Vinceae tribe of Apocynaceae family where most N-methylated MIAs have been identified in the phytochemical literature.


Asunto(s)
Apocynaceae , Catharanthus , Alcaloides de Triptamina Secologanina , Catharanthus/metabolismo , Regulación de la Expresión Génica de las Plantas , Alcaloides Indólicos/química , Metiltransferasas/genética , Metiltransferasas/metabolismo , Fitoquímicos/metabolismo , Proteínas de Plantas/metabolismo , Alcaloides de Triptamina Secologanina/metabolismo
17.
Polymers (Basel) ; 14(8)2022 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-35458274

RESUMEN

Although much research has been carried out in the field of the milling of GFRP (Glass Fibre Reinforced Polymer) composites, the complexity of the process is such that it is still not mastered in many industrial cases. The current work is aimed at studying the influence of three different geometries of PCD (PolyCrystalline Diamond) and cemented tungsten carbide cutting tools during the up-milling of GFRP composites at fixed cutting conditions (vc = 502 m/min and vf = 420 mm/min). Delamination, cutting forces and tool wear are compared at the fresh and worn states, and the correlation between the lifespan and the cost of the cutting tool is analysed. The main wearing phase of the tools was performed under the conditions of production in the facilities of a company (Sobelcomp, Loncin, Belgium). The results indicate that the PCD tool with the straight edge, inclined peripheral tooth shape produces the smallest total cutting force and less delamination (shortest and lowest number of delaminated fibres) at both fresh and worn states. Moreover, the grinding ability of PCD makes the cutting tool cost per part lower than for cemented carbide. The PCD tool is therefore the best option to mill GFRP parts.

18.
Front Plant Sci ; 13: 834447, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35371139

RESUMEN

Since the assessment of wheat diseases (e.g., leaf rust and tan spot) via visual observation is subjective and inefficient, this study focused on developing an automatic, objective, and efficient diagnosis approach. For each plant, color, and color-infrared (CIR) images were collected in a paired mode. An automatic approach based on the image processing technique was developed to crop the paired images to have the same region, after which a developed semiautomatic webtool was used to expedite the dataset creation. The webtool generated the dataset from either image and automatically built the corresponding dataset from the other image. Each image was manually categorized into one of the three groups: control (disease-free), disease light, and disease severity. After the image segmentation, handcrafted features (HFs) were extracted from each format of images, and disease diagnosis results demonstrated that the parallel feature fusion had higher accuracy over features from either type of image. Performance of deep features (DFs) extracted through different deep learning (DL) models (e.g., AlexNet, VGG16, ResNet101, GoogLeNet, and Xception) on wheat disease detection was compared, and those extracted by ResNet101 resulted in the highest accuracy, perhaps because deep layers extracted finer features. In addition, parallel deep feature fusion generated a higher accuracy over DFs from a single-source image. DFs outperformed HFs in wheat disease detection, and the DFs coupled with parallel feature fusion resulted in diagnosis accuracies of 75, 84, and 71% for leaf rust, tan spot, and leaf rust + tan spot, respectively. The methodology developed directly for greenhouse applications, to be used by plant pathologists, breeders, and other users, can be extended to field applications with future tests on field data and model fine-tuning.

19.
Porto Biomed J ; 7(4): e176, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36186115

RESUMEN

The purpose of this systematic review is to analyze the methodologies, utilized stimulation parameters, and the main cellular outcomes obtained by in vitro studies that apply a light source on tenocyte cultures. Methods: The PubMed, Scopus, and Web of Science databases were searched up to December 9, 2019 for in vitro studies that used light sources on tenocyte cultures. A 13-item checklist was used to assess methodological quality of the studies and the risk of bias was assessed using the Risk of Bias Assessment tool for Non-randomized Studies tool. Results: Six studies were included. Tenocytes from the Achilles tendon were used by 83.3% of the studies, with 16.7% utilizing the deep digital flexor tendon, with cells in passage 2 to 5. Four studies used lasers and the other 2 used light-emitting diode or intense pulsed light, in wavelengths ranges from 530 to 1100 nm. The application of light to tenocytes resulted in positive effects reported by all studies, including an increase in cell proliferation and migration, and higher protein and gene expression of tendon biomarkers. Studies presented a lack of standardization on reporting light stimulation parameters and experimental methodologies, leading to low methodological quality. There was a high risk of selection, performance, detection, and reporting bias. Conclusions: All studies showed positive effects after light stimulation on tenocytes, regardless of the light source used. However, the lack of standardized data on light stimulation parameters, experimental setup, and the studies' main limitations hindered representative conclusions and comparisons amongst studies' main outcomes.

20.
Int J Occup Saf Ergon ; 27(1): 217-225, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30810504

RESUMEN

Obesity is an emerging health problem and its incidence has been increasing throughout the workforce. In industrial workstations, vertical handling tasks (VHT), including lifting and lowering, are very common and can cause a significant muscular overload for the involved workers. During these tasks, muscular activity may be considerably affected by workers' body conditions. This study aims to analyze and compare the muscular activity in subjects with different obesity levels, using surface electromyography (EMG), during predefined VHT. Six different VHT (combining 5, 10 and 15-kg loads with two task styles) were performed. EMG data normalization was based on the percentage of maximum contraction during each task (MCT%). The results show that obesity influences the MCT%, which in turn increases the muscular effort during VHT. The current investigation demonstrates that obesity is a relevant musculoskeletal risk factor regarding VHT. The engineering analysis and design implications of this work can thus be perceived.


Asunto(s)
Contracción Isométrica , Elevación , Electromiografía , Humanos , Músculo Esquelético , Obesidad/epidemiología , Esfuerzo Físico
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