Esterases are hydrolases that catalyze the hydrolysis of esters into the corresponding acids and alcohols. The development of fluorescent probes for detecting esterases is of great importance due to ...their wide spectrum of biological and industrial applications. These probes can provide a rapid and sensitive method for detecting the presence and activity of esterases in various samples, including biological fluids, food products, and environmental samples. Fluorescent probes can also be used for monitoring the effects of drugs and environmental toxins on esterase activity, as well as to study the functions and mechanisms of these enzymes in several biological systems. Additionally, fluorescent probes can be designed to selectively target specific types of esterases, such as those found in pathogenic bacteria or cancer cells. In this review, we summarize the recent fluorescent probes described for the visualization of cell viability and some applications for in vivo imaging. On the other hand, positron emission tomography (PET) is a nuclear-based molecular imaging modality of great value for studying the activity of enzymes in vivo. We provide some examples of PET probes for imaging acetylcholinesterases and butyrylcholinesterases in the brain, which are valuable tools for diagnosing dementia and monitoring the effects of anticholinergic drugs on the central nervous system.
International mobility has become a key requirement in science and technology (S&T) professional career progression. On the one hand, the increasing mobility of women suggests that this may be a way ...for them to avoid or get away from women-unfriendly working environments. On the other hand, international mobility can present problems for women as they, particularly, have to plan their lives around their professional goals and personal lives. This article addresses the international mobility strategies of women regarding their personal and professional choices. We analyse their motivations to move, the way they manage their lives abroad and the effects of mobility on their lives. The analysis is based on 24 in-depth interviews of highly skilled women working in Spanish S&T sectors. Our main findings show that mobility is a new challenge which may improve women's family lives and professional careers. However, they have to plan carefully their lives on a long-term as well as a daily basis. In this sense, they need strong personal determination and the ability to balance their professional and personal goals. Moreover, their personal decisions depend not only on them as individuals, but also on their partners and families, on wider social values, on the institutional support they enjoy, and on the general public policies which they are affected by.
The objective of this study was to evaluate the sodium butyrate in the feeding of pirarucu juveniles, Arapaima gigas. Seventy - five juveniles of A. gigas (132.07 ± 3.12 g) were distributed in ...fifteen 310 L- tanks with constant aeration, filtration system and closed water recirculation. A completely randomized design the experiment, with four treatments including sodium butyrate (98%) in the diets (BS0 = control diet without sodium butyrate, BS1 = 0.5 g kg−1, BS2 = 1.0 g kg−1, BS3 = 1.5 g kg−1, BS4 = 2.0 g kg−1) with three replicates, and five juvenile treatment−1. The fish were fed three times day−1 (8, 12 and 16 h), until apparent satiety, for 45 days. Water quality parameters such as temperature, pH, dissolved oxygen and ammonia were monitored three times in the week. The growth parameters as weight gain, mean feed consumption, feed conversion ratio, specific growth rate, and survival were evaluated. It was performed chemical analysis of the whole body to establish dry matter, crude protein, ethereal extract, ash and gross energy. The hepatosomatic index and viscerosomatic index of juveniles also were evaluated. Histological sections of the intestine showed greater villous height and enzymatic activity of amylase, lipase and nonspecific alkaline protease. The blood plasma of juveniles was analyzed, as the hematocrit, total plasma protein concentration, triglyceride, glucose, and cholesterol. The inclusion of 1.17 g kg−1 of sodium butyrate in diets for A. gigas juveniles improves the growth parameters. This level favors feed conversion ratio increased intestinal villous height, without interfering in the blood parameters, and promote the adaptation of the enzymatic activity of amylase, lipase and nonspecific alkaline protease. Furthermore, it reduces the activity of aspartate aminotransferase and increases hepatic glycogen levels, making the animals more resistant to potentially stressful conditions in the growing environment.
•The additive sodium butyrate, up to 1.17 g kg−1, improves the growth parameters of piraruru juveniles (Arapaima gigas).•Sodium butyrate decreased apparent feed conversion of pirarucu juveniles.•The use of this additive increases the villus height of the anterior and middle intestine.•The use of sodium butyrate probably acts on the health of pirarucu, increasing the reserve glycogen.
Purpose
Adaptive Optics allows measurement and manipulation of the optical aberrations of the eye. We review two Adaptive Optics set‐ups implemented at the Visual Optics and Biophotonics Laboratory, ...and present examples of their use in better understanding of the role of optical aberrations on visual perception, in normal and treated eyes.
Recent findings
Two systems (AOI and AOII) are described that measure ocular aberrations with a Hartmann‐Shack wavefront sensor, which operates in closed‐loop with an electromagnetic deformable mirror, and visual stimuli are projected in a visual display for psychophysical measurements. AOI operates in infrared radiation (IR) light. AOII is provided with a supercontiniuum laser source (IR and visible wavelengths), additional elements for simulation (spatial light modulator, temporal multiplexing with optotunable lenses, phase plates, cuvette for intraocular lenses‐IOLs), and a double‐pass retinal camera. We review several studies undertaken with these AO systems, including the evaluation of the visual benefits of AO correction, vision with simulated multifocal IOLs (MIOLs), optical aberrations in pseudophakic eyes, chromatic aberrations and their visual impact, and neural adaptation to ocular aberrations.
Summary
Monochromatic and chromatic aberrations have been measured in normal and treated eyes. AO systems have allowed understanding the visual benefit of correcting aberrations in normal eyes and the adaptation of the visual system to the eye's native aberrations. Ocular corrections such as intraocular and contact lenses modify the wave aberrations. AO systems allow simulating vision with these corrections before they are implanted/fitted in the eye, or even before they are manufactured, revealing great potential for industry and the clinical practice. This review paper is part of a special issue of Ophthalmic & Physiological Optics on women in visual optics, and is co‐authored by all women scientists of the research team.
Ursolic acid is a pentacyclic triterpenoid found in several plants. Despite its initial use as a pharmacologically inactive emulsifier in pharmaceutical, cosmetic and food industries, several ...biological activities have been reported for this compound so far, including anti-tumoural, anti-diabetic, cardioprotective and hepatoprotective properties. The biological effects of ursolic acid have been evaluated in vitro, in different cell types and against several toxic insults (i.e. 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, amyloid-β peptides, kainic acid and others); in animal models of brain-related disorders (Alzheimer disease, Parkinson disease, depression, traumatic brain injury) and ageing; and in clinical studies with cancer patients and for muscle atrophy. Most of the protective effects of ursolic acid are related to its ability to prevent oxidative damage and excessive inflammation, common mechanisms associated with multiple brain disorders. Additionally, ursolic acid is capable of modulating the monoaminergic system, an effect that might be involved in its ability to prevent mood and cognitive dysfunctions associated with neurodegenerative and psychiatric conditions. This review presents and discusses the available evidence of the possible beneficial effects of ursolic acid for the management of neurodegenerative and psychiatric disorders. We also discuss the chemical features, major sources and potential limitations of the use of ursolic acid as a pharmacological treatment for brain-related diseases.
•Nine (9) experimental fire tests were developed on a reduced scale LSF wall to determine the insulation fire resistance.•Validation of the thermal model using the reduced scale ...experiments.•Validation of the thermal model and the mechanical model using the full scale experiments developed by other researchers.•Parametric analysis to determine the fire resistance (R) and (I) for the reduced and full scale LSF walls.•New proposal to determine the relationship between the critical temperature of the LSF and the load level.
Light Steel Frame (LSF) walls are widely used in building structures, used as partition walls and load bearing walls. The LSF is usually protected by layers of homogeneous plates or composite plates, with or without insulation materials in the cavity. This investigation presents the simulation results of composite LSF walls in reduced scale and full scale, based on variable load levels (20 to 80%). The numerical model uses a hybrid model approximation, based on the experimental tests to accurately determine the temperature field. The numerical model is validated with experimental results, at reduced and full scale, both at room temperature and under fire conditions. This modelling technique can follow the thermal and mechanical degradation of the protection layers of the LSF wall and determine the fire rating for load bearing (R) and insulation (I). The fire resistance (R) decreases with the increase of the load level. The insulation ability is also predicted for different protection materials. Relevant conclusions are presented to increase the insulation ability of LSF walls, especially when using non combustible double protection layers. The insulation ability to sustain fire usually increases with the number of studs and with the application of insulation material in the cavity region. The ability to sustain the load under fire also increases with the number of studs, especially for higher load levels. The ability to sustain the load also increases with the number of protection layers, changing from 16% at 20% load level, to 42% at 50% load level.
A new proposal is presented for the critical temperature of the LSF, based on the maximum temperature of the LSF during the fire, allowing the calculation of the critical temperature, based on the load level of the specimen. This relation can predict the fire resistance time, based on the preliminary thermal analysis of the specimen. The reduced scale specimens present higher critical temperatures when compared to the full scale specimens, due to the typical failure mode (local modes for the reduced scale and global modes for the large scale).
This paper presents a framework based on machine learning algorithms to predict nutrient content in leaf hyperspectral measurements. This is the first approach to evaluate macro- and micronutrient ...content with both machine learning and reflectance/first-derivative data. For this, citrus-leaves collected at a Valencia-orange orchard were used. Their spectral data was measured with a Fieldspec ASD FieldSpec® HandHeld 2 spectroradiometer and the surface reflectance and first-derivative spectra from the spectral range of 380 to 1020 nm (640 spectral bands) was evaluated. A total of 320 spectral signatures were collected, and the leaf-nutrient content (N, P, K, Mg, S, Cu, Fe, Mn, and Zn) was associated with them. For this, 204,800 (320 × 640) combinations were used. The following machine learning algorithms were used in this framework: k-Nearest Neighbor (kNN), Lasso Regression, Ridge Regression, Support Vector Machine (SVM), Artificial Neural Network (ANN), Decision Tree (DT), and Random Forest (RF). The training methods were assessed based on Cross-Validation and Leave-One-Out. The Relief-F metric of the algorithms’ prediction was used to determine the most contributive wavelength or spectral region associated with each nutrient. This approach was able to return, with high predictions (R2), nutrients like N (0.912), Mg (0.832), Cu (0.861), Mn (0.898), and Zn (0.855), and, to a lesser extent, P (0.771), K (0.763), and S (0.727). These accuracies were obtained with different algorithms, but RF was the most suitable to model most of them. The results indicate that, for the Valencia-orange leaves, surface reflectance data is more suitable to predict macronutrients, while first-derivative spectra is better linked to micronutrients. A final contribution of this study is the identification of the wavelengths responsible for contributing to these predictions.
The emergence of agricultural land use change creates a number of challenges that insect pollinators, such as eusocial bees, must overcome. Resultant fragmentation and loss of suitable foraging ...habitats, combined with pesticide exposure, may increase demands on foraging, specifically the ability to collect or reach sufficient resources under such stress. Understanding effects that pesticides have on flight performance is therefore vital if we are to assess colony success in these changing landscapes. Neonicotinoids are one of the most widely used classes of pesticide across the globe, and exposure to bees has been associated with reduced foraging efficiency and homing ability. One explanation for these effects could be that elements of flight are being affected, but apart from a couple of studies on the honeybee (Apis mellifera), this has scarcely been tested. Here, we used flight mills to investigate how exposure to a field realistic (10 ppb) acute dose of imidacloprid affected flight performance of a wild insect pollinator—the bumblebee, Bombus terrestris audax. Intriguingly, observations showed exposed workers flew at a significantly higher velocity over the first ¾ km of flight. This apparent hyperactivity, however, may have a cost because exposed workers showed reduced flight distance and duration to around a third of what control workers were capable of achieving. Given that bumblebees are central place foragers, impairment to flight endurance could translate to a decline in potential forage area, decreasing the abundance, diversity, and nutritional quality of available food, while potentially diminishing pollination service capabilities.
Using an experimental flight mill setup, we found that acute neonicotinoid exposure impaired flight endurance and affected flight velocity of Bombus terrestris workers. This study is the first to show such effects in a wild insect pollinator, with potential negative consequences for colony foraging capacity and pollination potential.
As the population ages, an epidemic of neurodegenerative diseases with devastating social consequences is looming. To address the pathologies leading to amyloid-related dementia, novel therapeutic ...strategies must be developed for the treatment or prevention of neural protein-folding disorders. Nanotechnology will be crucial to this scenario, especially in the design of nanoscale systems carrying therapeutic compounds that can navigate the nervous system and identify amyloid to treat it in situ. In this line, we have recently designed a highly simplified and versatile nanorobot consisting of a protein coating based on the heat shock protein 90 (Hsp90) chaperone that not only propels nanoparticles using ATP but also endows them with the extraordinary ability to fold and restore the activity of heat-denatured proteins. Here, we assess the effectiveness of these nanosystems in inhibiting/reducing the aggregation of amyloidogenic proteins. Using Raman spectroscopy, we qualitatively and quantitatively analyze amyloid by identifying and semi-quantifying the Amide I band. Our findings indicate that the coupling of Hsp90 to nanoparticles results in a more potent inhibition of amyloid formation when compared to the soluble protein. We propose that this enhanced performance may be attributed to enhanced release–capture cycles of amyloid precursor oligomers by Hsp90 molecules nearby on the nanosurface. Intelligent biocompatible coatings, like the one described here, that enhance the diffusivity and self-propulsion of nanoparticles while enabling them to carry out critical functions such as environmental scanning, identification, and amyloid prevention, present an exceptional opportunity for the development of advanced nanodevices in biomedical applications. This approach, which combined active biomolecules with synthetic materials, is poised to reveal remarkable prospects in the field of nanomedicine and biotechnology.
The semantic enrichment of mobility data with several information sources has led to a new type of movement data, the so‐called multiple aspect trajectories. Comparing multiple aspect trajectories is ...crucial for several analysis tasks such as querying, clustering, similarity, and classification. Multiple aspect trajectory similarity measurement is more complex and computationally expensive, because of the large number and heterogeneous aspects of space, time, and semantics that require a different treatment. Only a few works in the literature focus on optimizing all these dimensions in a single solution, and, to the best of our knowledge, none of them proposes a fast point‐to‐point comparison. In this article we propose the Multiple Aspect Trajectory Index, an index data structure for optimizing the point‐to‐point comparison of multiple aspect trajectories, considering its three basic dimensions of space, time, and semantics. Quantitative and qualitative evaluations show a processing time reduction of up to 98.1%.
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