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Translational Vision Science &... Sep 2022To provide a tool for calculating radial and tangential retinal magnifications as functions of field angle and retinal shape and to articulate patterns of magnification...
PURPOSE
To provide a tool for calculating radial and tangential retinal magnifications as functions of field angle and retinal shape and to articulate patterns of magnification across the retina for monocular and binocular combinations of prolate-, oblate-, and spherical-shaped retinas.
METHODS
Formulae were derived to calculate radial and tangential retinal magnifications (mm/deg) from field angle (degrees), retinal asphericity (unitless conic constant), retinal vertex radius of curvature (mm), and nodal point position (mm). Monocular retinal magnifications were determined for eyes with prolate, spherical, and oblate retinas as functions of field angle. Bilateral differences in magnifications were examined for combinations of those eyes.
RESULTS
Retinal shape substantially affects magnification profiles even for eyes with the same axial length. Greatest magnification changes across a retina and between eyes, as well as greatest increase in radial-tangential differences (distortion), occur with prolate retinas. Binocular magnification differences were smallest for oblate retinas. Nodal points anterior to the vertex center of curvature and oblate asphericity both cause field-dependent reductions in magnification relative to the fovea (barrel distortion), whereas nodal points posterior to vertex center of curvature and prolate asphericity cause the opposite (pincushion distortion). Retinal magnification differences due to eye shape are much greater than aniseikonia thresholds and chromatic differences in magnification. A spreadsheet tool implements the magnification calculations.
CONCLUSIONS
Local retinal magnifications as functions of field angle have substantial effects on objective applications (imaging retinal anatomy) and subjective experiences (aniseikonia) and quantify an ocular property that differs across eye shapes and refractive errors.
TRANSLATIONAL RELEVANCE
Methods are provided to customize the calculation of radial and tangential magnifications across the retina for individual eyes, which will bolster the multifactorial study of the effects of foveal and peripheral optics across eye shapes and refractive errors.
Topics: Aniseikonia; Humans; Phosmet; Radius; Refractive Errors; Retina; Visual Fields
PubMed: 36121677
DOI: 10.1167/tvst.11.9.10 -
The Science of the Total Environment Jan 2023Pesticide drift onto non-agricultural land is a common problem in intensively farmed regions, and national action plans have been established across Europe to prevent...
Pesticide drift onto non-agricultural land is a common problem in intensively farmed regions, and national action plans have been established across Europe to prevent it. Here, we analyzed official data on pesticide residues in grass samples collected over six years to determine whether implemented measures to reduce pesticide drift were effective. We used 306 samples collected between 2014 and 2020 on non-agricultural land in one of the most intensively managed apple and wine growing regions in Europe, the Autonomous Province of Bolzano-South Tyrol, Italy. Samples were analyzed for up to 314 substances by gas chromatography and mass spectrometry. Percentage of sites with multiple pesticides and number of pesticides decreased between 2014 and 2020. Fungicides were most often detected, with fluazinam found on 74 % and captan on 60 % of the contaminated sites (53 sites out of a total of 88 sites were contaminated). The most frequently found insecticide, phosmet, was detected in 49 % of the contaminated sites. Only one herbicide, oxadiazon, was detected in <1 % of the sites; glyphosate was not analyzed. The percentage of residues with human hazard properties increased significantly across years regarding reproductive toxicity (from 21 % of the detected substances in 2014 to 88 % in 2020) and specific target organ toxicity (0 % in 2014 to 21 % in 2020). Percentages of substances associated with endocrine-disruption (89 % of substances across years) or carcinogenic properties (45 % of substances across years) remained constant. The percentage of sites where concentrations in grass samples exceeded the surrogate maximum residue levels (MRLs) for lettuce also remained constant. Potential ecotoxicological hazards of detected residues regarding acute contact toxicity to honeybees remained high over the study years, while the acute and chronic toxicity to earthworms decreased. Our results suggest that while drift mitigation measures contributed some reduction in pesticide contamination, they were not sufficient to eliminate substantial risks to human health and the environment in nontarget areas.
Topics: Humans; Animals; Bees; Pesticides; Gas Chromatography-Mass Spectrometry; Pesticide Residues; Fungicides, Industrial; Europe
PubMed: 36115411
DOI: 10.1016/j.scitotenv.2022.158814 -
Soft Matter Sep 2022Active vesicles, constructed through the confinement of self-propelled particles (SPPs) inside a lipid membrane shell, exhibit a large variety of non-equilibrium shapes,...
Active vesicles, constructed through the confinement of self-propelled particles (SPPs) inside a lipid membrane shell, exhibit a large variety of non-equilibrium shapes, ranging from the formation of local tethers and dendritic conformations, to prolate and bola-like structures. To better understand the behavior of active vesicles, we perform simulations of membranes modelled as dynamically triangulated surfaces enclosing active Brownian particles. A systematic analysis of membrane deformations and SPP clustering, as a function of SPP activity and volume fraction inside the vesicle is carried out. Distributions of membrane local curvature, and the clustering and mobility of SPPs obtained from simulations of active vesicles are analysed. There exists a feedback mechanism between the enhancement of membrane curvature, the formation of clusters of active particles, and local or global changes in vesicle shape. The emergence of active tension due to the activity of SPPs can well be captured by the Young-Laplace equation. Furthermore, a simple numerical method for tether detection is presented and used to determine correlations between the number of tethers, their length, and local curvature. We also provide several geometrical arguments to explain different tether characteristics for various conditions. These results contribute to the future development of steerable active vesicles or soft micro-robots whose behaviour can be controlled and used for potential applications.
Topics: Lipid Bilayers; Molecular Conformation; Phosmet
PubMed: 36043635
DOI: 10.1039/d2sm00622g -
EFSA Journal. European Food Safety... Jul 2022According to Article 12 of Regulation (EC) No 396/2005, EFSA has reviewed the maximum residue levels (MRLs) currently established at European level for the pesticide...
According to Article 12 of Regulation (EC) No 396/2005, EFSA has reviewed the maximum residue levels (MRLs) currently established at European level for the pesticide active substance phosmet. Although this active substance is no longer authorised within the European Union, MRLs were established by the Codex Alimentarius Commission (codex maximum residue limits; CXLs). Based on the available data, EFSA assessed the CXLs and a consumer risk assessment was carried out. The CXLs were found to be supported by inadequate data and a possible chronic and acute risk to consumers was identified for several commodities. Hence, further consideration by risk managers is needed.
PubMed: 35873726
DOI: 10.2903/j.efsa.2022.7448 -
Physica Medica : PM : An International... Jul 2022Purpose Radioiodine therapy is used in most disease stages for differentiated thyroid cancer. Its success depends on several factors, such as lesion size, completeness...
Purpose Radioiodine therapy is used in most disease stages for differentiated thyroid cancer. Its success depends on several factors, such as lesion size, completeness of surgery, extent of metastasis and tumoural iodine avidity. We aimed to investigate the importance of non-spherical geometries and size of metastases and thyroid remnants for the absorbed dose delivered. Methods Absorbed doses and energy depositions from homogeneously distributed iodine-131 in clinically relevant geometries and sizes were calculated using Monte Carlo simulations with MCNP6. A total of 162 volumes with different sizes and geometries corresponding to spheres, and prolate or oblate spheroids were simulated. Results Oblate and prolate spheroids had worse radiation coverage compared to spheres for equal masses, up to a difference of 38% for the most eccentric oblate spheroids and smallest masses simulated (a micrometastasis of mass 0.005 g). The differences in coverage could be explained by different volume - to - surface - area ratios of the spheroids. The impact of size alone caused up to 71% lower absorbed doses per decay in a spherical target mass of 0.005 g compared to 50 g. Conclusions While the iodine avidity, and therefore the total amount of decays, is the predominant contributing factor to absorbed dose in radioiodine therapy, eccentric spheroids and small target sizes can receive substantially lower absorbed doses from the same administration of radioiodine.
Topics: Adenocarcinoma; Humans; Iodine Radioisotopes; Phosmet; Radiometry; Radiotherapy Dosage; Thyroid Neoplasms
PubMed: 35660791
DOI: 10.1016/j.ejmp.2022.05.010 -
The Analyst Jun 2022Surface enhanced Raman scattering (SERS) is an ultrasensitive analytic technique. However, the application of SERS in quantitative analysis usually suffers from poor...
Surface enhanced Raman scattering (SERS) is an ultrasensitive analytic technique. However, the application of SERS in quantitative analysis usually suffers from poor reliability due to the limitations of currently developed SERS substrates. In the present work, aggregated gold nanoparticles (a-AuNPs) fabricated by Ca-mediated assembly are dispersed in polyvinyl alcohol solution to prepare a novel hydrogel SERS chip through a physical crosslinking method. Taking advantage of the uniform distribution of SERS active a-AuNPs in the three-dimension hydrogel and the excellent barrier effect of hydrogel towards oxygen and macromolecules, the obtained hydrogel SERS chips show many outstanding advantages including high sensitivity, good repeatability, long-term stability, and a robust anti-interference ability. These advantages enable hydrogel SERS chips to be used to quantitatively analyse some complex samples without complex sample preprocessing. As a model, the hydrogel SERS chips are used for the detection of triazophos and phosmet in orange samples. The good recoveries suggest good applicability of the hydrogel SERS chips in food safety detection. This work provides a reliable and convenient platform for the quick detection and on-site monitoring of chemical contaminants and would promote greatly the performance of SERS techniques in quantitative analysis.
Topics: Gold; Hydrogels; Metal Nanoparticles; Organophosphorus Compounds; Pesticides; Reproducibility of Results; Spectrum Analysis, Raman
PubMed: 35611629
DOI: 10.1039/d2an00541g -
Food Chemistry Sep 2022Metal-organic frameworks (MOFs) have great potential to remove pesticide residues. However, the lack of affinity between the materials and target and the process of...
Facile synthesis disposable MOF membrane filter: Growth of NH-MIL-125 (Ti) on filter paper for fast removal of organophosphorus pesticides in aqueous solution and vegetables.
Metal-organic frameworks (MOFs) have great potential to remove pesticide residues. However, the lack of affinity between the materials and target and the process of trivial sample preparation resulted in limited removal efficiency. Here, we report a one-pot method for the fast preparation of NH-MIL-125 (Ti)-based filter paper to synthesise NH-MIL-125 (Ti)-based filter paper membranes. The NH-MIL-125 (Ti)-based filter paper membrane takes advantage of π-π interactions between the organophosphorus pesticides (OPPs) and the benzene ring of MOFs. The affinity of amino groups and metal Ti for phosphorus atoms in the OPPs exhibits rapid removal efficiency for three OPPs, imidan, fenthion, and fenitrothion. The isothermal adsorption results for imidan, fenthion, and fenitrothion were consistent with the Langmuir, Freundlich, and Langmuir models, respectively. The kinetic results for imidan, fenthion, and fenitrothion agreed with the pseudo-second-order kinetic model, and the removal efficiency reached equilibrium within 1 min. There was no significant change in the adsorption capacity of OPPs in different pH solutions (pH = 2-10). Compared with that of MOFs, the NH-MIL-125 (Ti)-based filter paper membrane removal efficiency of OPPs is the same, and it also has better removal efficiency in actual spinach samples. As a result, the sample pretreatment procedure was simplified using a low-cost and simple-to-synthesize disposable NH-MIL-125 (Ti)-based filter paper membrane, samples' quick separation and the simultaneous fast removal of OPPs.
Topics: Fenitrothion; Fenthion; Metal-Organic Frameworks; Organophosphorus Compounds; Pesticides; Phosmet; Titanium; Vegetables; Water
PubMed: 35490518
DOI: 10.1016/j.foodchem.2022.133056 -
Microscopy Research and Technique Jul 2022Pollen grains of 58 wetland species of angiosperms belonging to 17 families, growing in different wetlands of Sub-Himalayan biodiversity hotspots, Northern Bengal and...
Pollen grains of 58 wetland species of angiosperms belonging to 17 families, growing in different wetlands of Sub-Himalayan biodiversity hotspots, Northern Bengal and lower Gangetic plains, India were investigated during a 4-year span of 2015-2019. Freshly collected anthers were processed through the acetolysis method and the obtained pollen grains were accurately studied under LM and SEM and properly photographed. Different attributes viz. shape, size, aperture type and exine ornamentation of pollen grains served as consistent features were used for authentic identification of the studied species. To study the phylogeny of pollen grains, characters like polarity, symmetry, aperture and exine sculpturing were found most significant for species segregation. Investigated pollen grains were mostly prolate-spheroidal, spheroidal or triangular, rarely prolate or elongated, exine psilate, granulate, reticulate or microechinate type. Most of the observable aperture of pollen grains of studied species were colporate, colpate and porate, while ulcerate and inaperturate grains were also observed in the studied aquatic members of the families Cyperaceae and Potamogetonaceae. All the gathered data were further statistically analyzed through ANOVA, PCA and Pearson Correlation Matrix to understand the interrelationship among the species. The permanent slides of identified pollen grains were deposited at the herbarium of North Bengal University [NBU] for future references. HIGHLIGHTS: Study of Pollen morphology of 58 wetland species under light & scanning electron microscopy. Unique apertures and exine ornamentation used to understand taxonomic evaluation of studied species. Pollen character supports interrelationship among the studied species. Relationship between exine thickness and the habitat of the wetland plants.
Topics: Electrons; Humans; Magnoliopsida; Microscopy, Electron, Scanning; Phosmet; Pollen; Wetlands
PubMed: 35411986
DOI: 10.1002/jemt.24118 -
Microscopy Research and Technique Jul 2022Palynological characterization is considered to be one of the significant taxonomic tools for the delimitation and identification of morphologically complicated taxa....
Palynological characterization is considered to be one of the significant taxonomic tools for the delimitation and identification of morphologically complicated taxa. Hence, the pollen morphology of 12 species of spineless Astragalus L. was examined using light and scanning electron microscopy. Studied pollen were small to medium, monad, prolate to per-prolate and tricolporate type in all studied taxa. The exine sculpturing varied from reticulate to microreticulate whereas colpus ornamentation ranged from scabrate to granulate. Furthermore, maximum polar and equatorial diameter was recorded in Astragalus leucocephalus Bunge. (45.00 μm) and A. pyrrhotrichus Boiss. (22.91 μm) while minimum in A. amherstianus Benth. ex Royle (28.75 μm) and A. amherstianus Benth. ex Royle (15.00 μm), respectively. Similarly, the ratio of polar to equatorial diameter was recorded maximum in A. ophiocarpus Boiss. (2.05). The width of colpi was larger in A. hamosus L. (1.29 μm) and smaller in A. ophiocarpus Boiss. (0.62 μm). We have also found the maximum value of mesocolpium in A. retamocarpus Boiss. (2.08 μm) while minimum in A. oxyglottis Steven ex M.Bieb. (1.87 μm). The quantitative pollen attributes helped in the development of pollen keys for the accurate and quick identification of the studied species. Furthermore, ordination and cluster analysis were performed for the differentiation of the investigated taxa at species level. Based on our results, we conclude that pollen features can be used for the delimitation and identification of the studied taxa. RESEARCH HIGHLIGHTS: Pollen micromorphology is a useful tool for classifying complicated taxa. The pollen micromorphology of 12 spineless species of Astragalus L. was studied using LM and SEM. The observed pollen characteristics aided in Astragalus L. serve for the identification and classification of taxa at specific level.
Topics: Electrons; Fabaceae; Microscopy, Electron, Scanning; Phosmet; Pollen
PubMed: 35302261
DOI: 10.1002/jemt.24097 -
Microscopy Research and Technique Jul 2022This research aimed to explore the melliferous bee flora pollen from arid zones of District Attock, Islamabad Capital and Rawalpindi. Morpho-palynological features has...
This research aimed to explore the melliferous bee flora pollen from arid zones of District Attock, Islamabad Capital and Rawalpindi. Morpho-palynological features has provided key information for the classification and help to explain the taxonomy of several genera and species. Therefore, in this work, we examined the morphological characters of pollen potentially to be used for the species delimitation of bee flora. A total of 18 bee floral species, classified into 12 different families were collected, pressed, identified and then acetolyized to observe the grains under microscopy. Bee pollen can be described by small, medium to large sized morphotypes presenting five types of shapes, prolate spheroidal in (seven species), sub-prolate (six species), oblate spheroidal (three species), oblate and prolate (one species each) was examined. The observed polar and equatorial diameter were found maximum in Zea mays 73.5 μm and Pelargonium inquinans 66.75 μm respectively. Pollen of six different types was found namely: tricolporate, 3-zonocolporate, monoportae, tetracolporate, tetraporate and mononsulcate. Whereas highest value of colpi length was measured in Grewia tenax (24.55 μm). Exine surface nature of pollen was examined echinate psilate and scabrate. Exine thickness noted to be maximum in Verbena tenuisecta (8.40 μm) and minimum in Citrus macrocarpa (0.4 μm). Bee floral species considered difficult to identify based on other morphological traits were successfully distinguished using pollen quantitative and qualitative traits, confirming the importance of pollen morphology to diagnose characters to correctly identify honeybee flora. RESEARCH HIGHLIGHTS: Pollen diversity among honeybee flora. Highly variations observed via microscopy in pollen micromorphology. Palyno-morph has taxonomic value for the identification of honeybee floral species.
Topics: Animals; Bees; Microscopy, Electron, Scanning; Phenotype; Phosmet; Plants; Pollen
PubMed: 35247018
DOI: 10.1002/jemt.24091