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1.
Public Health Rev ; 45: 1606969, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38957684

RESUMEN

Objectives: We evaluated studies that used the World Health Organization's (WHO) AirQ and AirQ+ tools for air pollution (AP) health risk assessment (HRA) and provided best practice suggestions for future assessments. Methods: We performed a comprehensive review of studies using WHO's AirQ and AirQ+ tools, searching several databases for relevant articles, reports, and theses from inception to Dec 31, 2022. Results: We identified 286 studies that met our criteria. The studies were conducted in 69 countries, with most (57%) in Iran, followed by Italy and India (∼8% each). We found that many studies inadequately report air pollution exposure data, its quality, and validity. The decisions concerning the analysed population size, health outcomes of interest, baseline incidence, concentration-response functions, relative risk values, and counterfactual values are often not justified, sufficiently. Many studies lack an uncertainty assessment. Conclusion: Our review found a number of common shortcomings in the published assessments. We suggest better practices and urge future studies to focus on the quality of input data, its reporting, and associated uncertainties.

2.
Sci Rep ; 14(1): 8592, 2024 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-38615153

RESUMEN

Multifocal contact lenses (MCLs) are one of the solutions to correct presbyopia, but their adoption is not widespread. To address this situation, visual simulators can be used to refine the adaptation process. This study aims to obtain accurate simulations for a visual simulator (SimVis Gekko; 2EyesVision) of daily soft MCL designs from four manufacturers. In-vitro characterization of these MCLs-several powers and additions- was obtained using NIMO TR-1504. From the averaged relative power profiles across powers, phase maps were reconstructed and the Through-Focus Visual Strehl metric was calculated for each MCL design. The SimVis Gekko simulation corresponding to each MCL design was obtained computationally and bench-validated. Finally, the MCL simulations were clinically validated involving presbyopic patients. The clinical validation results show a good agreement between the SimVis Gekko simulations and the real MCLs for through-focus visual acuity (TF-VA) curves and VA at three real distances. All MCL designs showed a partial correlation higher than 0.90 and a Root Mean Square Error below 0.07 logMAR between the TF-VA of simulations and Real MCLs across subjects. The validity of the simulation approach using SimVis Gekko and in-vitro measurements was confirmed in this study, opening the possibility to accelerate the adaptation of MCLs.


Asunto(s)
Lentes de Contacto Hidrofílicos , Lagartos , Presbiopía , Humanos , Animales , Simulación por Computador , Presbiopía/terapia , Agudeza Visual
3.
Sci Total Environ ; 926: 171773, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38522546

RESUMEN

In water resources management, new computational capabilities have made it possible to develop integrated models to jointly analyze climatic conditions and water quantity/quality of the entire watershed system. Although the value of this integrated approach has been demonstrated so far, the limited availability of field data may hinder its applicability by causing high uncertainty in the model response. In this context, before collecting additional data, it is recommended first to recognize what improvement in model performance would occur if all available records could be well exploited. This work proposes a novel machine learning framework with physical constraints capable of successfully imputing a high percentage of missing data belonging to several environmental domains (meteorology, water quantity, water quality), yielding satisfactory results. In particular, the minimum NSE computed for meteorologic variables is 0.72. For hydrometric variables, NSE is always >0.97. More than 78 % of the physical-water-quality variables is characterized by NSE > 0.45, and >66 % of the chemical-water quality variables reaches NSE > 0.35. This work's results demonstrate the proposed framework's effectiveness as a data augmentation tool to improve the performance of integrated environmental modeling.

4.
Angew Chem Int Ed Engl ; 63(19): e202401107, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38358802

RESUMEN

The first total synthesis of dragocins A-C, remarkable natural products containing an unusual C4' oxidized ribose architecture bridged by a polyhydroxylated pyrrolidine, is presented through a route featuring a number of uncommon maneuvers. Several generations towards the target molecules are presented, including the spectacular failure of a key C-H oxidation on a late-stage intermediate. The final route features rapid, stereocontrolled access to a densely functionalized pyrrolidine and an unprecedented diastereoselective oxidative electrochemical cyclization to forge the hallmark 9-membered ring. Preliminary studies suggest this electrochemical oxidation protocol is generally useful.

5.
Environ Monit Assess ; 196(2): 175, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38240934

RESUMEN

The present study implements a methodology to estimate water quality values using statistical tools and remote sensing techniques in a tropical water body Sanalona. Linear regression models developed by Box-Cox transformations and processed data from LANDSAT-8 imagery (bands) were used to estimate TOC, TDS, and Chl-a of the Sanalona reservoir from 2013 to 2020 at five sampling sites measured every 6 months. A band discriminant analysis was carried out to statistically fit and optimize the proposed algorithms. Coefficients of determination beyond 0.9 were obtained for these water quality parameters (r2TOC = 0.90, r2TDS = 0.95, and r2Chl-a = 0.96). A comparison between the estimated and observed water quality was carried out using different data for validation. The validation of the models showed favorable results with R2TOC = 0.8525, R2TDS = 0.8172, and R2Chl-a = 0.9256. The present study implemented, validated, and compared the results obtained by using an ordered and standardized methodology proposed for the estimation of TOC, TDS, and Chl-a values based on water quality parameters measured in the field and using satellite images.


Asunto(s)
Clorofila , Tecnología de Sensores Remotos , Clorofila A/análisis , Clorofila/análisis , México , Monitoreo del Ambiente/métodos , Calidad del Agua , Algoritmos
6.
eNeuro ; 10(12)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37945351

RESUMEN

Serotonergic neurons in the rostral ventral medulla (RVM) contribute to bidirectional control of pain through modulation of spinal and trigeminal nociceptive networks. Deficits in this pathway are believed to contribute to pathologic pain states, but whether changes in serotonergic mechanisms are pro- or antinociceptive is debated. We used a combination of optogenetics and fiber photometry to examine these mechanisms more closely. We find that optogenetic activation of RVM serotonergic afferents in the spinal cord of naive mice produces mechanical hypersensitivity and conditioned place aversion (CPA). Neuropathic pain, produced by chronic constriction injury of the infraorbital nerve (CCI-ION), evoked a tonic increase in serotonin (5HT) concentrations within the spinal trigeminal nucleus caudalis (SpVc), measured with liquid chromatography-tandem mass spectroscopy (LC-MS/MS). By contract, CCI-ION had no effect on the phasic serotonin transients in SpVc, evoked by noxious pinch, and measured with fiber photometry of a serotonin sensor. These findings suggest that serotonin release in the spinal cord is pronociceptive and that an increase in sustained serotonin signaling, rather than phasic or event driven increases, potentiate nociception in models of chronic pain.


Asunto(s)
Neuralgia , Serotonina , Ratones , Animales , Serotonina/metabolismo , Hiperalgesia/metabolismo , Cromatografía Liquida , Espectrometría de Masas en Tándem , Asta Dorsal de la Médula Espinal , Médula Espinal/metabolismo , Neuralgia/metabolismo
7.
Biomed Opt Express ; 14(9): 4468-4484, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37791284

RESUMEN

Whole-eye optical coherence tomography (OCT) imaging is a promising tool in ocular biometry for cataract surgery planning, glaucoma diagnostics and myopia progression studies. However, conventional OCT systems are set up to perform either anterior or posterior eye segment scans and cannot easily switch between the two scan configurations without adding or exchanging optical components to account for the refraction of the eye's optics. Even in state-of-the-art whole-eye OCT systems, the scan configurations are pre-selected and cannot be dynamically reconfigured. In this work, we present the design, optimization and experimental validation of a reconfigurable and low-cost optical beam scanner based on three electro-tunable lenses, capable of non-mechanically controlling the beam position, angle and focus. We derive the analytical theory behind its control. We demonstrate its use in performing alternate anterior and posterior segment imaging by seamlessly switching between a telecentric focused beam scan to an angular collimated beam scan. We characterize the corresponding beam profiles and record whole-eye OCT images in a model eye and in an ex vivo rabbit eye, observing features comparable to those obtained with conventional anterior and posterior OCT scanners. The proposed beam scanner reduces the complexity and cost of other whole-eye scanners and is well suited for 2-D ocular biometry. Additionally, with the added versatility of seamless scan reconfiguration, its use can be easily expanded to other ophthalmic applications and beyond.

8.
Biomed Opt Express ; 14(8): 4261-4276, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37799671

RESUMEN

Quantifying human crystalline lens geometry as a function of age and accommodation is important for improved cataract and presbyopia treatments. In previous works we presented eigenlenses as a basis of 3-D functions to represent the full shape of the crystalline lens ex vivo. Also, we presented the application of eigenlenses to estimate the full shape of the lens in vivo from 3-D optical coherence tomography (OCT) images, where only the central part of the lens -visible through the pupil- is available. The current work presents a validation of the use of eigenlenses to estimate in vivo the full shape of dis-accommodated lenses. We used 14 ex vivo crystalline lenses from donor eyes (11-54 y/o) mounted in a lens stretcher, and measured the geometry and the power of the lenses using a combined OCT and ray tracing aberrometry system. Ex vivo, the full extent of the lens is accessible from OCT because the incident light is not blocked by the iris. We measured in non-stretched (fully accommodated) and stretched (mimicking in vivo dis-accommodated lenses) conditions. Then, we simulated computationally in vivo conditions on the obtained ex vivo lenses geometry (assuming that just the portion of the lens within a given pupil is available), and estimated the full shape using eigenlenses. The mean absolute error (MAE) between estimated and measured lens' diameters and volumes were MAE = 0.26 ± 0.18 mm and MAE = 7.0 ± 4.5 mm3, respectively. Furthermore, we concluded that the estimation error between measured and estimated lenses did not depend on the accommodative state (change in power due to stretching), and thus eigenlenses are also useful for the full shape estimation of in vivo dis-accommodated lenses.

9.
Angew Chem Int Ed Engl ; 62(42): e202309157, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37656907

RESUMEN

A mild, scalable (kg) metal-free electrochemical decarboxylation of alkyl carboxylic acids to olefins is disclosed. Numerous applications are presented wherein this transformation can simplify alkene synthesis and provide alternative synthetic access to valuable olefins from simple carboxylic acid feedstocks. This robust method relies on alternating polarity to maintain the quality of the electrode surface and local pH, providing a deeper understanding of the Hofer-Moest process with unprecedented chemoselectivity.

10.
J Cataract Refract Surg ; 49(11): 1153-1159, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37458453

RESUMEN

PURPOSE: To evaluate computationally the optical performance of AcrySof IQ Vivity extended depth-of-focus (EDOF) intraocular lenses (IOLs) in post-laser in situ keratomileusis (LASIK) eyes. SETTING: Visual Optics and Biophotonics Laboratory, Madrid, Spain. DESIGN: Experimental study. METHODS: Computer pseudophakic eye models were implemented using reported post-LASIK corneal aberrations (refractive corrections from -7.5 to +4.5 diopters [D]) and virtually implanted with monofocal (AcrySof IQ) or EDOF (AcrySof IQ Vivity) IOLs. Retinal image quality was quantified through visual Strehl (VS). The depth of focus (DOF) was calculated from the through-focus VS curves. Halos were estimated from the light spread in the image of a pinhole. Those quantitative parameters were obtained for 5.0 and 3.0 mm pupil diameters. RESULTS: Simulated virgin eyes showed VS of 0.89/0.99 with monofocal IOLs and 0.74/0.52 with EDOF IOLs for 5.0/3.0 mm pupils at best focus. VS decreased with induced spherical aberration (SA) by 25% and with induced SA + coma by 61% on average (3.0 mm pupils). The DOF was 2.50 D in virgin eyes with EDOF IOLs, 1.66 ± 0.30 and 2.54 ± 0.31 D ( P < .05) on average in post-LASIK eyes for 3.0 mm pupils, monofocal and EDOF IOLs, respectively. Halos were more sensitive to SA induction for 5.0 mm pupils, and induction of positive SA (myopic LASIK) resulted in reduced halos with the EDOF when compared with the monofocal IOLs, by 1.62 (SA) and 1.86 arc min (SA + coma), on average. CONCLUSIONS: Computer post-LASIK pseudophakic eye models showed that the DOF was less dependent on the presence of SA and coma with EDOF IOLs and that halos were reduced with EDOF IOLs compared with the monofocal IOL for a range of SA.


Asunto(s)
Queratomileusis por Láser In Situ , Lentes Intraoculares , Humanos , Agudeza Visual , Coma , Visión Ocular , Diseño de Prótesis
11.
Environ Res ; 231(Pt 1): 116029, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37149029

RESUMEN

INTRODUCTION: Air pollution health risk assessments have traditionally used single-pollutant effect estimates for one proxy ambient air pollutant such as PM2.5. Two-pollutant effect estimates, i.e. adjusted for another correlated pollutant, theoretically enable the aggregation of pollutant-specific health effects minimizing double-counting. Our study aimed at estimating the adult mortality in Switzerland in 2019 attributable to PM2.5 from a single-pollutant effect estimate and to the sum of PM2.5 and NO2 from two-pollutant estimates; comparing the results with those from alternative global, European and Swiss effect estimates. METHODS: For the single-pollutant approach, we used a PM2.5 summary estimate of European cohorts from the project ELAPSE, recommended by the European Respiratory Society and International Society for Environmental Epidemiology (ERS-ISEE). To derive the two-pollutant effect estimates, we applied ELAPSE-based conversion factors to ERS-ISEE PM2.5 and NO2 single-pollutant effect estimates. Additionally, we used World Health Organization 2021 Air Quality Guidelines as counterfactual scenario, exposure model data from 2019 and Swiss lifetables. RESULTS: The single-pollutant effect estimate for PM2.5 (1.118 [1.060; 1.179] per 10 µg/m3) resulted in 2240 deaths (21,593 years of life lost). Using our derived two-pollutant effect estimates (1.023 [1.012; 1.035] per 10 µg/m3 PM2.5 adjusted for NO2 and 1.040 [1.023; 1.058] per 10 µg/m3 NO2 adjusted for PM2.5), we found 1977 deaths (19,071 years of life lost) attributable to PM2.5 and NO2 together (23% from PM2.5). Deaths using alternative effect estimates ranged from 1042 to 5059. DISCUSSION: Estimated premature mortality attributable to PM2.5 alone was higher than to both PM2.5 and NO2 combined. Furthermore, the proportion of deaths from PM2.5 was lower than from NO2 in the two-pollutant approach. These seemingly paradoxical results, also found in some alternative estimates, are due to statistical imprecisions of underlying correction methods. Therefore, using two-pollutant effect estimates can lead to interpretation challenges in terms of causality.


Asunto(s)
Contaminantes Ambientales , Material Particulado , Material Particulado/toxicidad , Material Particulado/análisis , Dióxido de Nitrógeno/toxicidad , Dióxido de Nitrógeno/análisis , Suiza/epidemiología , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis
12.
Biomed Opt Express ; 14(5): 2138-2152, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37206127

RESUMEN

There is an increasing interest in applying optical coherence tomography (OCT) to quantify the topography of ocular structures. However, in its most usual configuration, OCT data is acquired sequentially while a beam is scanned through the region of interest, and the presence of fixational eye movements can affect the accuracy of the technique. Several scan patterns and motion correction algorithms have been proposed to minimize this effect, but there is no consensus on the ideal parameters to obtain a correct topography. We have acquired corneal OCT images with raster and radial patterns, and modeled the data acquisition in the presence of eye movements. The simulations replicate the experimental variability in shape (radius of curvature and Zernike polynomials), corneal power, astigmatism, and calculated wavefront aberrations. The variability of the Zernike modes is highly dependent on the scan pattern, with higher variability in the direction of the slow scan axis. The model can be a useful tool to design motion correction algorithms and to determine the variability with different scan patterns.

13.
Vive (El Alto) ; 6(16): 162-171, abr. 2023.
Artículo en Español | LILACS | ID: biblio-1442269

RESUMEN

Estudios recientes han planteado que el curso clínico puede ser crítico en niños debido a la naturaleza multifacética de la enfermedad. El Síndrome inflamatorio multisistémico asociado a SARS-CoV-2 (MIS-C), cursa con daño multisistémico, con predominio de afectación cardíaca que compromete la vida del paciente pediátrico. Objetivo. Identificar las principales alteraciones cardíacas por Síndrome inflamatorio multisistémico asociado a SARS-CoV-2 en pacientes pediátricos. Metodología. Se realizó una revisión sistemática mediante una búsqueda informativa en bases de datos. Se incluyeron estudios recientes publicados desde el año 2019 hasta el año 2022 que informaron acerca de las manifestaciones por afectación cardíaca, tratamiento en pacientes con alteración cardíaca por MIS-C y factores de riesgo asociados a MIS-C grave. Conclusiones. Las principales alteraciones cardiacas por síndrome inflamatorio multisistémico asociado a SARS-CoV-2 en pacientes pediátricos mostraron que las patologías más comunes fueron shock, arritmias cardíacas, derrame pericárdico, dilatación de las arterias coronarias y miocarditis aguda, por ende, las comorbilidades cardíacas son muy frecuentes en niños con MIS-C, donde, la afectación cardíaca y sistémica juega un papel muy importantes en el desarrollo de disfunción ventricular, miocarditis, anomalías de las arterias coronarias, arritmias y alteraciones del ritmo consideradas entres las más comunes.


Recent studies have suggested that the clinical course may be critical in children due to the multifaceted nature of the disease. The Multisystem Inflammatory Syndrome associated with SARS-CoV-2 (MIS-C) presents with multisystem damage, with a predominance of cardiac involvement that compromises the life of the pediatric patient. Objetive. To identify the main cardiac alterations due to Multisystem Inflammatory Syndrome associated with SARS-CoV-2 in pediatric patients. Methodology. A systematic review was carried out through an informative search in databases. Recent studies published from 2019 to 2022 that reported on manifestations due to cardiac involvement, treatment in patients with cardiac impairment due to MIS-C, and risk factors associated with severe MIS-C were included. Conclusions. The main cardiac alterations due to multisystem inflammatory syndrome associated with SARS-CoV-2 in pediatric patients showed that the most common pathologies were shock, cardiac arrhythmias, pericardial effusion, dilation of the coronary arteries and acute myocarditis, therefore, cardiac comorbidities are very high. Frequent in children with MIS-C, where cardiac and systemic involvement play a very important role in the development of ventricular dysfunction, myocarditis, coronary artery anomalies, arrhythmias, and rhythm disturbances considered among the most common.


Estudos recentes sugerem que o curso clínico pode ser crítico em crianças devido à natureza multifacetada da doença. A Síndrome Inflamatória multissistêmica associada ao SARS-CoV-2 (MIS-C) apresenta danos multissistêmicos, com predominância de acometimento cardíaco que compromete a vida do paciente pediátrico. Objetivo. Identificar as principais alterações cardíacas decorrentes da Síndrome Inflamatória multissistêmica associada ao SARS-CoV-2 em pacientes pediátricos. Metodologia. Uma revisão sistemática foi realizada por meio de uma pesquisa informativa em bancos de dados. Foram incluídos estudos recentes publicados de 2019 a 2022 que relataram manifestações devido ao envolvimento cardíaco, tratamento em pacientes com comprometimento cardíaco devido a MIS-C e fatores de risco associados a MIS-C grave. Conclusões. As principais alterações cardíacas devido à síndrome inflamatória multissistêmica associada ao SARS-CoV-2 em pacientes pediátricos mostraram que as patologias mais comuns foram choque, arritmias cardíacas, derrame pericárdico, dilatação das artérias coronárias e miocardite aguda, portanto, as comorbidades cardíacas são muito altas Frequente em crianças com MIS-C, onde o envolvimento cardíaco e sistêmico desempenha um papel muito importante no desenvolvimento de disfunção ventricular, miocardite, anomalias das artérias coronárias, arritmias e distúrbios do ritmo considerados entre os mais comuns.

14.
Biomed Opt Express ; 14(2): 608-626, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36874490

RESUMEN

Quantifying the full 3-D shape of the human crystalline lens is important for improving intraocular lens power or sizing calculations in treatments of cataract and presbyopia. In a previous work we described a novel method for the representation of the full shape of the ex vivo crystalline lens called eigenlenses, which proved more compact and accurate than compared state-of-the art methods of crystalline lens shape quantification. Here we demonstrate the use of eigenlenses to estimate the full shape of the crystalline lens in vivo from optical coherence tomography images, where only the information visible through the pupil is available. We compare the performance of eigenlenses with previous methods of full crystalline lens shape estimation, and demonstrate an improvement in repeatability, robustness and use of computational resources. We found that eigenlenses can be used to describe efficiently the crystalline lens full shape changes with accommodation and refractive error.

15.
J Exp Biol ; 226(4)2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36728594

RESUMEN

We compared the fecal microbial community composition and diversity of four replicate lines of mice selectively bred for high wheel-running activity over 81 generations (HR lines) and four non-selected control lines. We performed 16S rRNA gene sequencing on fecal samples taken 24 h after weaning, identifying a total of 2074 bacterial operational taxonomic units. HR and control mice did not significantly differ for measures of alpha diversity, but HR mice had a higher relative abundance of the family Clostridiaceae. These results differ from a study of rats, where a line bred for high forced-treadmill endurance and that also ran more on wheels had lower relative abundance of Clostridiaceae, as compared with a line bred for low endurance that ran less on wheels. Within the HR and control groups, replicate lines had unique microbiomes based on unweighted UniFrac beta diversity, indicating random genetic drift and/or multiple adaptive responses to selection.


Asunto(s)
Microbioma Gastrointestinal , Ratones , Ratas , Animales , ARN Ribosómico 16S , Prueba de Esfuerzo , Modelos Animales de Enfermedad , Estado Nutricional
16.
J Dev Orig Health Dis ; 14(2): 249-260, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36193024

RESUMEN

Fructose (C6H12O6) is acutely obesogenic and is a risk factor for hypertension, cardiovascular disease, and nonalcoholic fatty liver disease. However, the possible long-lasting effects of early-life fructose consumption have not been studied. We tested for effects of early-life fructose and/or wheel access (voluntary exercise) in a line of selectively bred High Runner (HR) mice and a non-selected Control (C) line. Exposures began at weaning and continued for 3 weeks to sexual maturity, followed by a 23-week "washout" period (equivalent to ∼17 human years). Fructose increased total caloric intake, body mass, and body fat during juvenile exposure, but had no effect on juvenile wheel running and no important lasting effects on adult physical activity or body weight/composition. Interestingly, adult maximal aerobic capacity (VO2max) was reduced in mice that had early-life fructose and wheel access. Consistent with previous studies, early-life exercise promoted adult wheel running. In a 3-way interaction, C mice that had early-life fructose and no wheel access gained body mass in response to 2 weeks of adult wheel access, while all other groups lost mass. Overall, we found some long-lasting positive effects of early-life exercise, but minimal effects of early-life fructose, regardless of the mouse line.


Asunto(s)
Actividad Motora , Condicionamiento Físico Animal , Humanos , Ratones , Animales , Actividad Motora/fisiología , Composición Corporal/fisiología , Tejido Adiposo , Ingestión de Energía , Condicionamiento Físico Animal/fisiología
17.
Biomed Opt Express ; 14(12): 6521-6541, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38420323

RESUMEN

Optical biometers are routinely used to measure intraocular distances in ophthalmic applications such as cataract surgery planning or myopia monitoring. However, due to their high cost and reduced transportability, access to them for screening and surgical planning is still limited in low-resource and remote settings. To increase patients' access to optical biometry we propose a novel low-cost frequency-domain optical delay line (FD-ODL) based on an inexpensive stepper motor spinning a tilted mirror, for integration into a time-domain (TD)-biometer, amenable to a compact footprint. In the proposed FD-ODL, the axial scan range and the A-scan rate are decoupled from one another, as the former only depends on the spinning mirror tilt angle, while the A-scan rate only depends on the motor shaft rotational speed. We characterized the scanning performance and specifications for two spinning mirror tilt angles, and compared them to those of the standard, more expensive FD-ODL implementation, employing a galvanometric scanner for group delay generation. A prototype of the low-cost FD-ODL with a 1.5 deg tilt angle, resulting in an axial scan range of 6.61 mm and an A-scan rate of 10 Hz was experimentally implemented and integrated in a dual sample beam optical low-coherence reflectometry (OLCR) setup with a detour unit to replicate the measurement window around the anterior segment and the retina. The intraocular distances of a model eye were measured with the proposed low-cost biometer and found to be in good agreement with those acquired by a custom swept-source optical coherence tomography (SS-OCT) system and two commercial biometers, validating our novel design.

18.
J Exp Biol ; 225(23)2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36408738

RESUMEN

A trade-off between locomotor speed and endurance occurs in various taxa, and is thought to be underpinned by a muscle-level trade-off. Among four replicate high runner (HR) lines of mice, selectively bred for voluntary wheel-running behavior, a negative correlation between average running speed and time spent running has evolved. We hypothesize that this trade-off is due to changes in muscle physiology. We studied the HR lines at generation 90, at which time one line (L3) is fixed for the mini-muscle phenotype, another is polymorphic (L6) and the others (L7, L8) lack mini-muscle individuals. We used in situ preparations to quantify the contractile properties of the triceps surae muscle complex. Maximal shortening velocity varied significantly, being lowest in mini-muscle mice (L3 mini=25.2 mm s-1, L6 mini=25.5 mm s-1), highest in normal-muscle mice L6 and L8 (40.4 and 50.3 mm s-1, respectively) and intermediate in normal-muscle L7 mice (37.2 mm s-1). Endurance, measured both as the slope of the decline in force and the proportion of initial force that could be sustained, also varied significantly. The slope was shallowest in mini-muscle mice (L3 mini=-0.00348, L6 mini=-0.00238), steepest in lines L6 and L8 (-0.01676 and -0.01853), and intermediate in L7 (-0.01145). Normalized sustained force was highest in mini-muscle mice (L3 mini=0.98, L6 mini=0.92) and lowest in L8 (0.36). There were significant, negative correlations between velocity and endurance metrics, indicating a muscle-level trade-off. However, this muscle-level trade-off does not seem to underpin the organismal-level speed and endurance trade-off previously reported as the ordering of the lines is reversed: the lines that run the fastest for the least time have the lowest muscle complex velocity and highest endurance.


Asunto(s)
Músculos , Ratones , Animales
19.
J Environ Manage ; 322: 116137, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36067670

RESUMEN

Impact of natural phenomena and anthropogenic activities on water quality is closely related with temperature increase and global warming. In this study, the effects of climate change scenarios on water quality forecasts were assessed through correlations, prediction algorithms, and water quality index (WQI) for tropical reservoirs. The expected trends for different water quality parameters were estimated for the 2030-2100 period in association with temperature trends to estimate water quality using historical data from a dam in Mexico. The WQI scenarios were obtained using algorithms supported by global models of representative concentration pathways (RCPs) adopted by the Intergovernmental Panel on Climate Change (IPCC). The RPCs were used to estimate water and air temperature values and extrapolate future WQI values for the water reservoir. The proposed algorithms were validated using historical information collected from 2012 to 2019 and four temperature variation intervals from 3.2 to 5.4 °C (worst forecast) to 0.9-2.3 °C (best forecast) were used for each trajectory using 0.1 °C increases to obtain the trend for each WQI parameter. Variations in the concentration (±30, ±70, and +100) of parameters related to anthropogenic activity (e.g., total suspended solids, fecal coliforms, and chemical oxygen demand) were simulated to obtain water quality scenarios for future health diagnosis of the reservoir. The results projected in the RCP models showed increasing WQI variation for lower temperature values (best forecast WQI = 74; worst forecast WQI = 71). This study offers a novel approach that integrates multiparametric statistical and WQI to help decision making on sustainable water resources management for tropical reservoirs impacted by climate change.


Asunto(s)
Cambio Climático , Calidad del Agua , Análisis de la Demanda Biológica de Oxígeno , México , Recursos Hídricos
20.
Chem Sci ; 13(22): 6512-6518, 2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35756520

RESUMEN

Herein, we report, a general, facile and environmentally friendly Minisci-type alkylation of N-heteroarenes under simple and straightforward electrochemical conditions using widely available alkyl halides as radical precursors. Primary, secondary and tertiary alkyl radicals have been shown to be efficiently generated and coupled with a large variety of N-heteroarenes. The method presents a very high functional group tolerance, including various heterocyclic-based natural products, which highlights the robustness of the methodology. This applicability has been further proved in the synthesis of various interesting biologically valuable building blocks. In addition, we have proposed a mechanism based on different proofs and pieces of electrochemical evidence.

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