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1.
Sensors (Basel) ; 24(15)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39123868

RESUMEN

Social interactions are characterized by being very diverse and changing over time. Understanding this diversity and dynamics, as well as their emerging patterns, is of great interest from social, health, and educational perspectives. The development of new devices has been made possible in recent years by advances in applied technology. This paper presents the design and development of a novel device composed of several sensors. Specifically, we propose a proximity sensor integrated by three devices: a Bluetooth sensor, a global positioning system (GPS) unit and an accelerometer. By means of this sensor it is possible to detect the presence of neighboring sensors in various configurations and operating conditions. Profiles based on the Received Signal Strength Indicator (RSSI) exhibit behavior consistent with that reported by empirical relationships. The present sensor is functional in detecting the proximity of other sensors and is thus useful for the identification of interactions between people in relevant contexts such as schools.

2.
Sci Total Environ ; 947: 174653, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39002588

RESUMEN

Countries within the tropics face ongoing challenges in completing or updating their national forest inventories (NFIs), critical for estimating aboveground biomass (AGB) and for forest-related greenhouse gas (GHG) accounting. While previous studies have explored the integration of map information with local reference data to fill in data gaps, limited attention has been given to the specific challenges presented by the clustered plot designs frequently employed by NFIs when combined with remote sensing-based biomass map units. This research addresses these complexities by conducting four country case-studies, encompassing a variety of NFI characteristics within a range of AGB densities. Examining four country case-studies (Peru, Guyana, Tanzania, Mozambique), we assess the potential of European Space Agency's Climate Change Initiative (CCI) global biomass maps to increase precision in (sub)national AGB estimates. We compare a baseline approach using NFI field-based data with a model-assisted scenario incorporating a locally calibrated CCI biomass map as auxiliary information. The original CCI biomass maps systematically underestimate AGB in three of the four countries at both the country and stratum level, with particularly weak agreement at finer map resolution. However, after calibration with country-specific NFI data, stratum and country-level AGB estimates from the model-assisted scenario align well with those obtained solely from field-based data and official country reports. Introducing maps as a source of auxiliary information fairly increased the precision of stratum and country-wise AGB estimates, offering greater confidence in estimating AGB for GHG reporting purposes. Considering the challenges tropical countries face with implementing their NFIs, it is sensible to explore the potential benefits of biomass maps for climate change reporting mechanisms across biomes. While country-specific NFI design assumptions guided our model-assisted inference strategies, this study also uncovers transferable insights from the application of global biomass maps with NFI data, providing valuable lessons for climate research and policy communities.


Asunto(s)
Biomasa , Cambio Climático , Monitoreo del Ambiente , Monitoreo del Ambiente/métodos , Bosques , Tanzanía , Clima Tropical , Mozambique , Guyana , Gases de Efecto Invernadero/análisis
3.
Sci Rep ; 14(1): 11182, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755294

RESUMEN

Parallel computing is a current algorithmic approach to looking for efficient solutions; that is, to define a set of processes in charge of performing at the same time the same task. Advances in hardware permit the massification of accessibility to and applications of parallel computing. Nonetheless, some algorithms include steps that require or depend on the results of other steps that cannot be parallelized. Speculative computing allows parallelizing those tasks and reviewing different execution flows, which can involve executing invalid steps. Speculative computing solutions should reduce those invalid flows. Product configuration refers to selecting features from a set of available options respecting some configuration constraints; a not complex task for small configurations and models, but a complex one for large-scale scenarios. This article exemplifies a videogame product line feature model and a few configurations, valid and non-valid, respectively. Configuring products of large-scale feature models is a complex and time-demanding task requiring algorithmic solutions. Hence, parallel solutions are highly desired to assist the feature model product configuration tasks. Existing solutions follow a sequential computing approach and include steps that depend on others that cannot be parallelized at all, where the speculative computing approach is necessary. This article describes traditional sequential solutions for conflict detection and diagnosis, two relevant tasks in the automated analysis of feature models, and how to define their speculative parallel version, highlighting their computing improvements. Given the current parallel computing world, we remark on the advantages and current applicability of speculative computing for producing faster algorithmic solutions.

4.
J. oral res. (Impresa) ; 13(1): 37-46, mayo 29, 2024. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1563178

RESUMEN

Introduction: The morphology of the root canal of the first premolars is not always the same and therefore a good knowledge of its dental anatomy is essential. Aim: To assess the morphology of roots and root canals of mandibular first premolars in a Peruvian population using cone-beam computed tomography (CBCT). Materials and Methods: This was a descriptive cross-sec-tional study. A total of 370 mandibular first premolars fulfilling the inclusion criteria were evaluated using CBCT, and the number of roots and root canals, the Vertucci's classification of root canal configuration, age, sex and side of the tooth were registered. Results: One and two roots were presented in 96.2% (n=356) and 3.8% (n=14), respectively, of the mandibular first premolars analyzed, and one canal was present in 67.6% (n=250) and two canals in 32.2% (n=119). A type I root canal configuration was found in 67.6% (n=250) of the cases followed by type V with 26.2% (n=97). A statistically significant association was found between the number of roots and canals (p<0.001) and age also had a significant influence on this variable (p=0.0043). Conclusions: The presence of one canal in mandibular first premolars is the most frequent, although there is a considerable prevalence of two in the population studied. The number of roots is associated with the number of canals, with age having a significant influence on these variables.


Introducción: La morfología del canal radicular de los primeros premolares no siempre es la misma y por ello es fundamental un buen conocimiento de su anatomía dental. Objetivo: Evaluar la morfología de las raíces y conductos radiculares de primeros premolares mandibulares en una población peruana mediante tomografía computarizada de haz cónico. Materiales y Métodos: Este fue un estudio transversal descriptivo. Se evaluaron mediante tomografías un total de 370 primeros premolares mandibulares que cumplían con los criterios de inclusión, y se registró el número de raíces y conductos radiculares, la clasificación de Vertucci de la configuración radicular, la edad, el sexo y el lado del diente. Se realizaron las pruebas de chi-cuadrado y una regresión logística binaria (p<0,05). Resultado: Se presentó una y dos raíces en el 96,2% (n=356) y 3,8% (n=14), respectivamente, de los primeros premolares mandibulares analizados, y un canal estuvo presente en el 67,6% (n=250) y dos canales en el 32,2% (n=119). Se encontró una configuración del conducto radicular tipo I en el 67,6% (n=250) de los casos seguido del tipo V con un 26,2% (n=97). Se encontró una asociación estadísticamente significativa entre el número de raíces y conductos (p<0.001) y la edad también influyó significativamente en esta variable (p=0.0043). Conclusión: La presencia de 1 canal en primeros premolares mandibulares es la más frecuente, aunque existe una prevalencia considerable de 2 en la población estudiada. El número de raíces está asociado al número de canales, teniendo la edad una influencia significativa en estas variables.


Asunto(s)
Humanos , Diente Premolar/anatomía & histología , Cavidad Pulpar/anatomía & histología , Cavidad Pulpar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Perú/epidemiología , Epidemiología Descriptiva , Mandíbula/anatomía & histología , Mandíbula/diagnóstico por imagen
5.
Int. j. morphol ; 42(2): 483-490, abr. 2024. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1558154

RESUMEN

SUMMARY: Failure to locate a complete canal system affects the prognosis of root canal treatment. A missed root canal is one of the most common reasons for failed root canal treatment. The prevalence of the second mesiobuccal canal in the maxillary second molar is relatively high and has a variety of configurations. Therefore, knowledge of its morphology is required in clinical endodontics. This review presented the canal in terms of its prevalence, classification, anatomical features, and the method for locating the second mesiobuccal canal in the maxillary second molar. Root canal treatment requires knowledge of tooth morphology, appropriate access preparation, and a thorough examination of the tooth's interior. Thus, clinicians should carefully employ various methods for assessing the anatomy of the entire root canal system to prevent failure in locating the second mesiobuccal canal. This canal can be located by modifying the access cavity design and utilizing specific instruments to improve the second mesiobuccal canal system visualization.


La falta de localización de un sistema completo de canal afecta el pronóstico del tratamiento de éste. La omisión de un tratamiento de canal es uno de los motivos más frecuentes por las que el tratamiento de canal fracasa. La prevalencia del segundo canal mesiovestibular en el segundo molar superior es relativamente alta y tiene una variedad de configuraciones. Por tanto, el conocimiento de su morfología es necesario en endodoncia clínica. Esta revisión presentó el canal en términos de su prevalencia, clasificación, características anatómicas y el método para localizar el segundo canal mesiovestibular en el segundo molar superior. El tratamiento de canal requiere conocimiento de la morfología del diente, una preparación adecuada del acceso y un examen exhaustivo del interior del diente. Por lo tanto, los dentistas deben emplear cuidadosamente varios métodos para evaluar la anatomía de todo el sistema de canales radiculares para evitar fallas en la localización del segundo canal mesiovestibular. Este canal se puede localizar modificando el diseño de la cavidad de acceso y utilizando instrumentos específicos para mejorar la visualización del sistema del segundo canal mesiovestibular.


Asunto(s)
Humanos , Raíz del Diente/anatomía & histología , Cavidad Pulpar/anatomía & histología , Diente Molar/anatomía & histología , Prevalencia , Clasificación , Maxilar
6.
Int. j. morphol ; 42(1): 28-34, feb. 2024. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1528823

RESUMEN

SUMMARY: This work investigated the morphology of the root canal system of the mandibular first molar in a Malaysian subpopulation. Using micro-computed tomography with an isotropic resolution of 22 µm, 140 mandibular first molars were scanned. MIMICS software was used for segmentation, 3-D reconstruction and analysis of the acquired images. The canal configuration was described using Vertucci [supported by the supplementary configurations proposed by Sert & Bayirli (2004)] and Ahmed et al. (2027), coding systems. The chi-square test was used to assess the association between qualitative variables. By non-considering intercanal communications, Vertucci types IV (17.1%) and I (76.4%) were the most frequently reported configurations in the mesial and distal roots, respectively. Of the reported configurations, 24.3% and 4.3% were non-classifiable by Vertucci system in the mesial and distal roots, respectively. Up to 63.6% and 9.3% of the reported configurations were non- classifiable, and type I was the most frequent when considering intercanal communications (7.1% and 76.4% in the mesial and distal roots, respectively). According to Ahmed et al., system, almost half of the sample had more than four digits (47.9%), followed by the 3-digits category (20.71%). In both systems, a significant association was found between the canal configuration and the root type (p<0.001). The mandibular first molar of this Malaysian subpopulation demonstrated a wide range of root canal morphology. When compared to the Vertucci system, the system developed by Ahmed et al., successfully classified all molars configurations despite their level of complexity. The complex canal anatomy of mandibular first molars in this subpopulation warrants special attention during root canal treatment procedures.


En este trabajo se investigó la morfología del sistema de conductos radiculares del primer molar mandibular en una subpoblación de Malasia. Utilizando tomografía microcomputada con una resolución isotrópica de 22 µm, se escanearon 140 primeros molares mandibulares. Se utilizó el software MIMICS para segmentar (enmascarar), reconstruir en 3D, visualizar y analizar las imágenes adquiridas. La configuración del canal se describió utilizando Vertucci respaldado por las configuraciones complementarias propuestas por Sert & Bayirli (2004)] y Ahmed et al. (2017, 2020), sistemas de codificación. Se utilizó la prueba de chi-cuadrado para evaluar la asociación entre variables cualitativas. Sin considerar las comunicaciones intercanales, los tipos Vertucci IV (17,1%) y I (76,4%) fueron las configuraciones reportadas con mayor frecuencia en las raíces mesiales y distales, respectivamente. De las configuraciones reportadas, el 24,3 % y el 4,3 % fueron no clasificables por el sistema de Vertucci en las raíces mesial y distal, respectivamente. Hasta el 63,6 % y el 9,3 % de las configuraciones reportadas fueron no clasificables, siendo la tipo I la más frecuente al considerar las comunicaciones intercanales (7,1 % y 76,4 % en las raíces mesiales y distales, respectivamente). Según Ahmed et al. (2017, 2020) en el sistema, casi la mitad de la muestra tenía más de cuatro dígitos (47,9 %), seguido por la categoría de 3 dígitos (20,71 %). En ambos sistemas se encontró una asociación significativa entre la configuración del canal y el tipo de raíz (p<0,001). El primer molar mandibular de esta subpoblación de Malasia demostró una amplia gama morfológica del conducto radicular. En comparación con el sistema Vertucci, el sistema desarrollado por Ahmed et al. (2017, 2020) clasificaron con éxito todas las configuraciones de los molares a pesar de su nivel de complejidad. La compleja anatomía del canal de los primeros molares mandibulares en esta subpoblación merece una atención especial durante los procedimientos de tratamiento de conducto.


Asunto(s)
Humanos , Cavidad Pulpar/diagnóstico por imagen , Microtomografía por Rayos X , Diente Molar/diagnóstico por imagen , Cavidad Pulpar/anatomía & histología , Malasia , Diente Molar/anatomía & histología
7.
Proc Inst Mech Eng H ; 238(2): 198-206, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38193256

RESUMEN

Ankle arthrodesis is the gold standard for treatment of end-stage arthritis. The goal of ankle arthrodesis is to obtain bony union between the tibia and the talus. Retrograde intramedullary nailing is typically reserved for ankle and subtalar joints arthrodesis. The purpose of this study is to evaluate the effect of two different materials, two locking pin configurations and two nail designs of a retrograde locked intramedullary nail used for ankle arthrodesis. Using the finite element analysis, a numerical study of ankle arthrodesis was developed to evaluate the effect of materials: TI-6Al-4V and stainless steel AISI 316 LVM; two locking pin configurations: five and six pins, on two intramedullary nails: Ø10 × 180 mm and Ø11 × 200 mm. A model of a healthy foot was created from tomographic scans. It was found that the mechanical stimulus required to achieve bone fusion were higher for Ø10 × 180 nails (6.868 ± 0.047) than the Ø11 × 200 nails (5.918 ± 0.047; p < 0.001; mean ± SEM). We also found that six-pin configuration had a higher mechanical stimulus (6.470 ± 0.047) than the five-pin configuration (6.316 ± 0.046; p = 0.020). Similarly, it was higher for titanium (6.802 ± 0.047) than those for stainless steel (5.984 ± 0.046; p < 0.001). Finally, the subtalar zone presented higher values (7.132 ± 0.043) than the tibiotalar zone (5.653 ± 0.050; p < 0.001). The highest mechanical stimulus around the vicinity of tibiotalar and subtalar joint was obtained by Ø10 × 180 nails, made of titanium alloy, with 6P.


Asunto(s)
Tobillo , Fijación Intramedular de Fracturas , Análisis de Elementos Finitos , Acero Inoxidable , Titanio , Clavos Ortopédicos , Articulación del Tobillo/diagnóstico por imagen , Articulación del Tobillo/cirugía , Fijación Intramedular de Fracturas/métodos , Artrodesis
8.
Molecules ; 28(21)2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37959864

RESUMEN

Four novel seconeodolastane diterpenoids, named tricholomalides D-G, were isolated, together with the known tricholomalide C, from the fruiting bodies of Tricholoma ustaloides Romagn., a species belonging to the large Tricholoma genus of higher mushrooms (Basidiomycota, family Tricholomataceae). They were isolated through multiple chromatographic separations, and the structures, including the absolute configuration, were established through a detailed analysis of MS, NMR, and CD spectral data and comparison with related compounds reported in the literature, which has been thoroughly revised.


Asunto(s)
Fagus , Tricholoma , Madera , Tricholoma/química , Espectroscopía de Resonancia Magnética
9.
Pharmaceutics ; 15(9)2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37765161

RESUMEN

The use of the USP IV apparatus (flow-through cell) has gained acceptance in recent years due to its versatility and ability to discriminate due to its hydrodynamic conditions. Therefore, the objective of the present study was to develop a discriminative dissolution method in the USP IV apparatus using the open-loop configuration, as well as to propose a method to compare non-cumulative dissolution profiles obtained in the open-loop configuration considering kinetic parameters and validate its predictive power through its comparison with independent and dependent methods using five commercial immediate-release tablet drugs (one reference drug and four generic drugs) of metoprolol tartrate as a model drug. The comparison of the non-accumulated dissolution profiles consisted of determining the geometric ratio of Cmax, AUC0∞, AUC0Cmax, and Tmax (kinetic parameters) of the generic/reference drugs, whereby generic drugs "C" and "D" presented the highest probability of similarity since their 90% confidence intervals were included, or they were very close to the acceptance interval (80.00-125.00%). These results were consistent with the f2, bootstrap f2, and dissolution efficiency approaches (independent models). In conclusion, the proposed comparison method can be an important tool to establish similarity in dissolution profiles and to facilitate the development/selection of new formulations and positively ensure bioequivalence in clinical studies.

10.
Materials (Basel) ; 16(16)2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37630012

RESUMEN

In the present work, different configurations of nt iartificial neural networks (ANNs) were analyzed in order to predict the experimental diameter of nanofibers produced by means of the electrospinning process and employing polyvinyl alcohol (PVA), PVA/chitosan (CS) and PVA/aloe vera (Av) solutions. In addition, gelatin type A (GT)/alpha-tocopherol (α-TOC), PVA/olive oil (OO), PVA/orange essential oil (OEO), and PVA/anise oil (AO) emulsions were used. The experimental diameters of the nanofibers electrospun from the different tested systems were obtained using scanning electron microscopy (SEM) and ranged from 93.52 nm to 352.1 nm. Of the three studied ANNs, the one that displayed the best prediction results was the one with three hidden layers with the flow rate, voltage, viscosity, and conductivity variables. The calculation error between the experimental and calculated diameters was 3.79%. Additionally, the correlation coefficient (R2) was identified as a function of the ANN configuration, obtaining values of 0.96, 0.98, and 0.98 for one, two, and three hidden layer(s), respectively. It was found that an ANN configuration having more than three hidden layers did not improve the prediction of the experimental diameter of synthesized nanofibers.

11.
J Forensic Sci ; 68(5): 1792-1799, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37435865

RESUMEN

The automated search software integrated with a scanning electron microscope (SEM/EDS) has been the standard tool for detecting inorganic gunshot residues (iGSR) for several decades. The detection of these particles depends on various factors such as collection, preservation, contamination with organic matter, and the method for sample analysis. This article focuses on the influence of equipment resolution setup on the backscattered electron images of the sample. The pixel size of these images plays a crucial role in determining the detectability of iGSR particles, especially those with sizes close to the pixel size. In this study, we calculated the probability of missing all characteristic iGSR particles in a sample using an SEM/EDS automated search and how it depends on the image pixel resolution setup. We developed and validated an iGSR particle detection model that links particle size with equipment registers and applied it to 320 samples analyzed by a forensic science laboratory. Our results show that the probability of missing all characteristic iGSR particles due to their size is below 5% for pixel sizes below 0.32 µm2 . These findings indicate that pixel sizes as large as twice the one commonly used in laboratory casework, that is, 0.16 µm2 , are effective for initial sample scanning, yielding good detection rates of characteristic particles that could exponentially reduce laboratory workload.

12.
Nanomaterials (Basel) ; 13(14)2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37513134

RESUMEN

In this work, the SET and RESET processes of bipolar resistive switching memories with silicon nanocrystals (Si-NCs) embedded in an oxide matrix is simulated by a stochastic model. This model is based on the estimation of two-dimensional oxygen vacancy configurations and their relationship with the resistive state. The simulation data are compared with the experimental current-voltage data of Si-NCs/SiO2 multilayer-based memristor devices. Devices with 1 and 3 Si-NCs/SiO2 bilayers were analyzed. The Si-NCs are assumed as agglomerates of fixed oxygen vacancies, which promote the formation of conductive filaments (CFs) through the multilayer according to the simulations. In fact, an intermediate resistive state was observed in the forming process (experimental and simulated) of the 3-BL device, which is explained by the preferential generation of oxygen vacancies in the sites that form the complete CFs, through Si-NCs.

13.
Int J Mol Sci ; 24(8)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37108653

RESUMEN

For biomedical applications, gelatin is usually modified with methacryloyl groups to obtain gelatin methacryloyl (GelMA), which can be crosslinked by a radical reaction induced by low wavelength light to form mechanically stable hydrogels. The potential of GelMA hydrogels for tissue engineering has been well established, however, one of the main disadvantages of mammalian-origin gelatins is that their sol-gel transitions are close to room temperature, resulting in significant variations in viscosity that can be a problem for biofabrication applications. For these applications, cold-water fish-derived gelatins, such as salmon gelatin, are a good alternative due to their lower viscosity, viscoelastic and mechanical properties, as well as lower sol-gel transition temperatures, when compared with mammalian gelatins. However, information regarding GelMA (with special focus on salmon GelMA as a model for cold-water species) molecular conformation and the effect of pH prior to crosslinking, which is key for fabrication purposes since it will determine final hydrogel's structure, remains scarce. The aim of this work is to characterize salmon gelatin (SGel) and salmon methacryloyl gelatin (SGelMA) molecular configuration at two different acidic pHs (3.6 and 4.8) and to compare them to commercial porcine gelatin (PGel) and methacryloyl porcine gelatin (PGelMA), usually used for biomedical applications. Specifically, we evaluated gelatin and GelMA samples' molecular weight, isoelectric point (IEP), their molecular configuration by circular dichroism (CD), and determined their rheological and thermophysical properties. Results showed that functionalization affected gelatin molecular weight and IEP. Additionally, functionalization and pH affected gelatin molecular structure and rheological and thermal properties. Interestingly, the SGel and SGelMA molecular structure was more sensitive to pH changes, showing differences in gelation temperatures and triple helix formation than PGelMA. This work suggests that SGelMA presents high tunability as a biomaterial for biofabrication, highlighting the importance of a proper GelMA molecular configuration characterization prior to hydrogel fabrication.


Asunto(s)
Gelatina , Ingeniería de Tejidos , Animales , Gelatina/química , Temperatura de Transición , Viscosidad , Suspensiones , Ingeniería de Tejidos/métodos , Metacrilatos/química , Salmón , Hidrogeles/química , Conformación Molecular , Agua , Mamíferos
14.
J Mol Model ; 29(3): 77, 2023 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-36840887

RESUMEN

In this work the diastereoisomers (2S) and (2R)-naringenin-6-C-ß-D-glucopyroside, isolated for the first time from Clitoria guianensis, were studied using the density functional theory. The frontier molecular orbitals and structural properties showed that the diastereoisomers exhibit the same energy gap 166.61 kcal mol-1 and structural properties different, where in the S diastereoisomer, the bond length between the chiral carbon and the phenolic group is greater (difference of 0.0126 Å). The HPLC data showed that the retention time of the S-diastereoisomer (16.7 min) is shorter than that of R, suggesting that the S compound is more polar than R. The HPLC results corroborates with the molecular electrostatic potential which showed that in the S configuration, the electronegative density was more intense overall, particularly in the glucose molecule. The reactivity indices showed that the diastereoisomers are good electrophiles and reactive species. Finally, the absolute configuration of the diastereoisomers were determined using electronic circular dichroism (ECD) spectroscopy and the theoretical spectra were similar to the experimental. METHODS : All calculations of Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TDDFT) were performed using the program Gaussian 09 and the structures of the diastereoisomers were generated and analyzed using the GaussView program. The optimization and vibrational frequency calculations were performed using the functional CAM-B3LYP and 6-311 + + G(2d,2p) basis set. Conformational searches were performed for R configuration, by molecular mechanics using the MM + , MMFF, and OPLS05 force fields; the entire molecular mechanics simulation was performed using the Maestro/MacroModel software. The calculations for the simulations of the ECD spectra were performed for the eight lowest energy conformers obtained in the geometric optimization step, and the TDDFT at the CAM-B3LYP/6-311 + + G(2d,2p) theory level used. The effects of methanol and chloroform were calculated using the SMD implicit solvent model.


Asunto(s)
Clitoria , Estructura Molecular , Dicroismo Circular , Conformación Molecular
15.
Bull Entomol Res ; 113(1): 63-71, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35899975

RESUMEN

Bemisia tabaci is a complex of species, which is considered the most common and important pest of a wide range of crops belonging to many different botanical families. In Argentina, this species is recognized as a vector of geminiviruses, and Middle East-Asia Minor 1, Mediterranean, New World and New World 2 have been found to coexist in the same area. Landscape elements, like habitat patch area and isolation, define the habitat configuration and have a direct effect on insect populations between and within host patches. In this paper, we analyse the effect of potato patch configuration on the distribution and abundance of B. tabaci. Potato patches were identified using Landsat TM5 and TM7 images, and a supervised classification was performed to quantify the spatial distribution of the patches in the whole study area. Potato patch metrics were estimated using Fragstats 4.4. Generalized linear mixed models were employed to analyse the relationship between whiteflies and landscape configuration, through a multimodel inference approach, finding that B. tabaci abundance and landscape metrics were very variable. After a multimodel selection process, we found that perimeter-to-area ratio and Euclidean distance between patches were the variables that best explained whitefly abundance in potato patches. Implications of these findings are discussed.


Asunto(s)
Hemípteros , Solanum tuberosum , Animales , Argentina , Productos Agrícolas , Medio Oriente
16.
Chirality ; 35(1): 67-79, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36398355

RESUMEN

Evaluation of DFT calculated vibrational parameters for the IR and VCD spectra similarity of perezone (1) and dihydroperezone (2) was undertaken. Conformational sets were obtained using different search engines, and the parameters needed for spectra prediction were obtained using several combinations of commonly employed functionals and basis sets, and then weighted spectra were generated and compared with observed traces to provide infrared similarity (SIR ) and enantiomeric similarity index (ESI) values. These values evidenced a poor performance of the evaluated levels of theory that were overcome when using the individual scaling factors approach, providing 16% to 139% increases of the ESI values. The best performing level of theory was the B3LYP/DGDZVP2 with ESI values of 0.722 and 0.792 for 1 and 2. Moreover, a correlation analysis showed that the irregular DFT performance arises from rotational strength deviations, which suggests to discard conformational abundance accuracy as the main source of differences. Furthermore, a similarity guided conformational analysis showed that conformations with high ESI values prefer particular orientations of the CC bonds directly attached to the stereogenic carbon atom, with more distant dihedral angles having less influence. Additionally, folded and extended conformers appear to be equally capable to yield high individual ESI values, although abundances of folded conformers just account for 16% of the total population. Nevertheless, abundance optimization showed that a high ESI similarity value of 0.834, is possible when the population of these conformers is increased to 26%, suggesting that a larger abundance of these conformers might be present in solution.


Asunto(s)
Dicroismo Circular , Estereoisomerismo , Modelos Moleculares , Conformación Molecular
17.
Data Brief ; 42: 108267, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35647241

RESUMEN

The presented datasets relate to the research article entitled "Native forest meta-community structures in Uruguay shaped by novel land use types in their surroundings" [Ramírez and Säumel; Ecology and Evolution, 2022]. The datasets include field survey data on woody species presence and absence from 384 plots at 32 permanent monitoring sites of native forests across the Oriental Republic of Uruguay (South America). We compiled different methods from meta-community studies, remote sensing and landscape ecology to explore how woody species communities are influenced by land use change from local to regional scale. We describe the diverse woody species composition in native forests across Uruguay and structure of metacommunities of woody species. Data on woody species diversity inform landscape planning, land-use management, policy and governance and can be used for further meta-analysis with other local, regional or global data sets.

18.
Ecol Evol ; 12(3): e8700, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35342551

RESUMEN

We explore the effect of land-use change from extensively used grasslands to intensified silvi- and agricultural monocultures on metacommunity structure of native forests in Uruguay. We integrated methods from metacommunity studies, remote sensing, and landscape ecology to explore how woody species distribution was influenced by land-use change from local to regional scale. We recorded richness and composition of adult and juvenile woody species from 32 native forests, created land-use maps from satellite image to calculate spatial metrics at landscape, class, and patch levels. We also analyzed the influence of land use pattern, climate, topography, and geographic distance between sites (d) on metacommunity, and created maps to visualize species richness and (dis)similarity between communities across the country. Woody species communities were distributed in a discrete pattern across Uruguay. Precipitation and temperature seasonality shaped species distribution pattern. Species richness and community dissimilarity increased from West to East. Latitude did not influence these patterns. Number of patches, landscape complexity, and interspersion and juxtaposition indexes determine woody species distribution at landscape level. Increasing areas covered by crops and timber plantation reduced species richness and increased community dissimilarity. The spatial metrics of native forest fragments at patch level did not influence metacommunity structure, species richness, and community dissimilarity. In conclusion, Uruguayan native forests display a high range of dissimilarity. Pressure of neighborhood land uses was the predominant factor for species assemblages. Conserving landscape structures that assure connectivity within and among native forest patches is crucial. On sites with rare target species, the creation of alliances between governmental institution and landowner complemented by incentives for biodiversity conservation provides opportunities to advance in species protection focused on those less tolerant to land-use change.

19.
Entropy (Basel) ; 24(1)2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35052150

RESUMEN

For the formation of a proto-tissue, rather than a protocell, the use of reactant dynamics in a finite spatial region is considered. The framework is established on the basic concepts of replication, diversity, and heredity. Heredity, in the sense of the continuity of information and alike traits, is characterized by the number of equivalent patterns conferring viability against selection processes. In the case of structural parameters and the diffusion coefficient of ribonucleic acid, the formation time ranges between a few years to some decades, depending on the spatial dimension (fractional or not). As long as equivalent patterns exist, the configuration entropy of proto-tissues can be defined and used as a practical tool. Consequently, the maximal diversity and weak fluctuations, for which proto-tissues can develop, occur at the spatial dimension 2.5.

20.
Aust Endod J ; 48(3): 409-414, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34626050

RESUMEN

This study aimed to compare the main root canal configurations of mandibular incisors (MI) in a Brazilian population using Vertucci and Ahmed et al. classifications. One hundred and sixty-five human permanent MI were scanned using a micro-CT. Two examiners classified the samples according to Vertucci and Ahmed et al. classification. Kappa coefficient was employed. The majority of MI had a single root canal (52.1%). Type III Vertucci and 1 MI1-2-1 Ahmed et al. was the most common 2-canal MI (20%). In the apical third, the presence of one, two and three canals was found in 81.8%, 15.2% and 3% respectively. In the cervical and middle thirds, one, two and three canals were found in 86%, 12.2% and 1.8% respectively. Ahmed et al. classification was able to classify the entire sample studied, whereas 11 teeth (6.66%) did not fit Vertucci's classification.


Asunto(s)
Cavidad Pulpar , Raíz del Diente , Humanos , Cavidad Pulpar/diagnóstico por imagen , Mandíbula/diagnóstico por imagen , Incisivo/diagnóstico por imagen , Tratamiento del Conducto Radicular , Tomografía Computarizada de Haz Cónico
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