Range Of Values Research Articles

Endothelial cell loss post-implantable collamer lens V4c: meta-analysis.

Endothelial cell density (ECD) loss is a noted effect of implantable collamer lens (ICL) V4c surgery. Current literature provides a wide range of values for ECD loss postsurgery, which may not be helpful in advising patients and clinicians. A meta-analysis exploring ECD loss in ICL V4c for myopia correction was undertaken. 18 studies were included in this meta-analysis with 2 subgroup analyses to account for the variability in follow-up lengths. The average ECD loss 3 months, 12 months, and 21.25 (mean) months postsurgery were 1.32% ± 1.28% ( P < .001, 95% CI, -75.158 to -1.19), 1.75% ± 2.17% ( P < .001, 95% CI, -134.09 to 14.52), and 3.84% ± 1.78% ( P < .001, 95% CI, -156.04 to -54.26), respectively. ECD loss is most pronounced 3 months postsurgery, suggesting that acute surgical trauma was the primary contributor rather than long-term lens implantation. Overall, ICL V4c is for myopia correction exhibits similar ECD loss as seen in other ICL models, thereby affirming its safety.

Effect of maximum packing fraction of powders on the rheology of metakaolin-based geopolymer pastes

In this work, we study the effect of maximum packing fraction of powders on the rheology of geopolymer pastes. A large range of metakaolin powders is generated either by blending or grinding powders. Blends of metakaolin with quartz and limestone are also studied. We show that the compressive packing model is able to predict correctly over a wide range of values the maximum packing fraction of these powders. We show that an increase of the maximum packing of powders leads to a decrease of the viscosity of geopolymer suspension at a constant solid volume fraction. We finally show that the viscosity of studied geopolymer suspensions can be well predicted by the Krieger Dougherty relation. We suggest that the highest potential degree of freedom allowing for the control of the viscosity of geopolymer pastes without modifying the composition of the suspension lies in the maximum packing fraction of the solid powders.

Multigrid simulations of non-Newtonian fluid flow and heat transfer in a ventilated square cavity with mixed convection and baffles

The impact of baffles on a convective heat transfer of a non-Newtonian fluid is experimentally studied within a square cavity. The non-Newtonian fluid is pumped into the cavity through the inlet and subsequently departs from the cavity via the outlet. Given the inherent non-linearity of the model, a numerical technique has been selected as the method for obtaining the outcomes. Primarily, the governing equations within the two-dimensional domain have been discretized using the finite element method. For approximating velocity and pressure, we have employed the reliable P2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathbb{P}}_{2}$$\\end{document}–P1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathbb{P}}_{1}$$\\end{document} finite element pair, while for temperature, we have opted for the quadratic basis. To enhance convergence speed and accuracy, we employ the powerful multigrid approach. This study investigates how key parameters like Richardson number (Ri), Reynolds number (Re), and baffle gap bg\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{\ ext{b}}}_{{\ ext{g}}}$$\\end{document} influence heat transfer within a cavity comprising a non-Newtonian fluid. The baffle gap (bg\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${b}_{g}$$\\end{document}) has been systematically altered within the range of 0.2–0.6, and for this research, three distinct power law indices have been selected namely: 0.5, 1.0, and 1.5. The primary outcomes of the investigation are illustrated through velocity profiles, streamlines, and isotherm visualizations. Furthermore, the study includes the computation of the Nuavg\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${Nu}_{avg}$$\\end{document}(average Nusselt number) across a range of parameter values. As the Richardson number (Ri) increases, Nuavg\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${Nu}_{avg}$$\\end{document} also rises, indicating that an increase in Ri results in augmented average heat transfer. Making the space between the baffles wider makes heat flow more intense. This, in turn, heats up more fluid within the cavity.

Psychometric evidence of the mobile dependence test in the young population of Lima in the context of the pandemic

With the intention of estimating the psychometric properties of the mobile dependency test applied in the youth of Lima in the context of the pandemic, psychometric and instrumental design research has been carried out. The scale was administered to the 380 participants using non-probability sampling. It has been verified that the values of the goodness of fit of the original scale are outside the range of optimal values. The adjustment of factors was carried out by eliminating items 7 and 19 and obtaining the re-specified model of four factors with accumulated variance of 52.82%. The factor analysis of the re-specified model yielded acceptable goodness of fit values with x2/ gl = 2.8; RMSEA = .069; SRMR = .051; CFI = .92 and TLI = .90. The reliability of the total scale showed very good results in Cronbach's alpha and McDonalds Omega (.923 and .922). Finally, it was determined that the re- specified 4-factor scale with the items eliminated reveals the certainty of reliability and validity

Analysis of NDVI and Plant Vegetation Diversity in the Traditional Zone, Mount Halimun Salak National Park, Bogor

Mount Halimun Salak National Park (MHSNP) traditional zone is a zone which is highly utilized by the local community to fulfill their daily needs by utilizing non-timber forest resources and implementing an agroforestry system with the main commodity is poh-pohan (Pilea melastomoides). Forest monitoring in the MHSNP traditional zone is very important to do as part of sustainable forest management and the realization of supporting Indonesia's Forestry And Other Land Use (FOLU) Net Sink 2030 program. This study aims to analyze the density of vegetation based on NDVI values; besides, analyze the level of plant species diversity and stand structure in the traditional zone of MHSNP. Furthermore, the data collection of plant species diversity at the area based on NDVI value of vegetation density. NDVI values ​​are obtained into three classes that have different land conditions. The class 1 value range from 0.147 to 0.273 has a low vegetation density. Class 2 from 0.273 to 0.319 has medium vegetation density. Meanwhile, class 3 has high vegetation density with a value of 0.319 to 0.433. Diversity of plant species has 60 different species from a total of three classes. The density of seedlings is lower than saplings and at the level of poles, trees is decreasing that is indicates a balanced stand structure. The low seedling level is caused by inhibition of seedling growth due to cleaning by the local community in preparation for planting understory since the community prefers to plant understory which harvest faster woody plant seedling.

Including a wider range of values in healthcare policy: how can public value evaluation help?

To meet future healthcare challenges a broader range of values need to be included in analysis, debate and policy. Different modes of governance foreground and facilitate different values. Collaboration, the governing principle of the newly formed integrated care systems, values the contribution of diverse stakeholders in discussions and decisions, to foster creativity and produce durable solutions to complex problems. Approaches to evaluation reinforce particular values, as captured in the adage 'what's measured is what matters'. New approaches are needed to support the collaborative aims of integrated care systems. Public value evaluation proceeds through values inquiry, establishing what is important to different stakeholders (including policy makers, healthcare staff, patients and communities) as a backdrop to understanding the effects of policies and programmes.

Determining Effective Threshold Range of Image Pixel Values for Municipal Waste-Contaminated Clay

Determining Effective Threshold Range of Image Pixel Values for Municipal Waste-Contaminated Clay

Random genetic drift sets an upper limit on mRNA splicing accuracy in metazoans

Most eukaryotic genes undergo alternative splicing (AS), but the overall functional significance of this process remains a controversial issue. It has been noticed that the complexity of organisms (assayed by the number of distinct cell types) correlates positively with their genome-wide AS rate. This has been interpreted as evidence that AS plays an important role in adaptive evolution by increasing the functional repertoires of genomes. However, this observation also fits with a totally opposite interpretation: given that ‘complex’ organisms tend to have small effective population sizes (Ne), they are expected to be more affected by genetic drift, and hence more prone to accumulate deleterious mutations that decrease splicing accuracy. Thus, according to this ‘drift barrier’ theory, the elevated AS rate in complex organisms might simply result from a higher splicing error rate. To test this hypothesis, we analyzed 3496 transcriptome sequencing samples to quantify AS in 53 metazoan species spanning a wide range of Ne values. Our results show a negative correlation between Ne proxies and the genome-wide AS rates among species, consistent with the drift barrier hypothesis. This pattern is dominated by low abundance isoforms, which represent the vast majority of the splice variant repertoire. We show that these low abundance isoforms are depleted in functional AS events, and most likely correspond to errors. Conversely, the AS rate of abundant isoforms, which are relatively enriched in functional AS events, tends to be lower in more complex species. All these observations are consistent with the hypothesis that variation in AS rates across metazoans reflects the limits set by drift on the capacity of selection to prevent gene expression errors.

Random genetic drift sets an upper limit on mRNA splicing accuracy in metazoans.

Most eukaryotic genes undergo alternative splicing (AS), but the overall functional significance of this process remains a controversial issue. It has been noticed that the complexity of organisms (assayed by the number of distinct cell types) correlates positively with their genome-wide AS rate. This has been interpreted as evidence that AS plays an important role in adaptive evolution by increasing the functional repertoires of genomes. However, this observation also fits with a totally opposite interpretation: given that 'complex' organisms tend to have small effective population sizes (Ne), they are expected to be more affected by genetic drift, and hence more prone to accumulate deleterious mutations that decrease splicing accuracy. Thus, according to this 'drift barrier' theory, the elevated AS rate in complex organisms might simply result from a higher splicing error rate. To test this hypothesis, we analyzed 3496 transcriptome sequencing samples to quantify AS in 53 metazoan species spanning a wide range of Ne values. Our results show a negative correlation between Ne proxies and the genome-wide AS rates among species, consistent with the drift barrier hypothesis. This pattern is dominated by low abundance isoforms, which represent the vast majority of the splice variant repertoire. We show that these low abundance isoforms are depleted in functional AS events, and most likely correspond to errors. Conversely, the AS rate of abundant isoforms, which are relatively enriched in functional AS events, tends to be lower in more complex species. All these observations are consistent with the hypothesis that variation in AS rates across metazoans reflects the limits set by drift on the capacity of selection to prevent gene expression errors.

Genetic Analysis of M5 Generation of Gamma Irradiated Red Rice (Oryza sativa L.) Mutant lines

In rice, induced mutations play a significant role in development of semi dwarf and high yielding variants. The genetic variability induced by four Gamma rays treatments was studied in traditional red rice variety Kajejaya in Randomized complete block design with two replications during Kharif 2021. Analysis of variance documented Gamma rays treatment brought significant variability and exhibited a wide range of values for all traits. Six superior mutants(T35-L-06, T35-L-17, T35-L-15, T45-L-07 T45-L-13 and T45-L-06) exhibited more number of productive tillers/plant, panicle length, number of filled grains/panicle, high test weight and higher grain yield/plant and T45-L-13, T45-L-06 and T35-L-15 mutants took lesser days to mature(114,117.5 and 118 days) and exhibited reduced plant height(84, 80 and 72cm) compared to untreated parent check. Induced mutations were effective in creating variability in plant height and maturity duration along with increased mean of reproductive components at higher doses (35kR and 45kR) as compared to lower doses(15kR and 25kR).

Concept and Interpretation of Confidence Interval: How to Overcome Limitations of P-value

Knowing the estimate (mean or proportion) for the whole population is not feasible due to a lack of resources. Therefore, we rely on a sample estimate to draw conclusions about the population. The range of values in which the true population estimate lies is called a confidence interval (CI) which is more reliable than single estimate. For descriptive studies, CIs should be reported along with the point estimate (mean or proportion). For effect sizes in inferential statistics (mean difference, odds ratio, risk ratio, etc.), the p-value should be supplemented with a CI for strength and direction of the association.

Iodine quantification of renal lesions: Preliminary results using spectral-based material extraction on photon-counting CT

Objectives: To assess the range of quantitative iodine values in renal cysts (RC) (with a few renal neoplasms [RNs] as a comparison) to develop an expected range of values for RC that can be used in future studies for their differentiation. Material and Methods: Consecutive patients (n = 140) with renal lesions who had undergone abdominal examination on a clinical photon-counting computed tomography (PCCT) were retrospectively included. Automated iodine quantification maps were reconstructed, and region of interest (ROI) measurements of iodine concentration (IC) (mg/cm3) were performed on whole renal lesions. In addition, for heterogeneous lesions, a secondary ROI was placed on the area most suspicious for malignancy. The discriminatory values of minimum, maximum, mean, and standard deviation for IC were compared using simple logistic regression and receiver operating characteristic curves (area under the curve [AUC]). Results: A total of 259 renal lesions (243 RC and 16 RN) were analyzed. There were significant differences between RC and RN for all IC measures with the best-performing metrics being mean and maximum IC of the entire lesion ROI (AUC 0.912 and 0.917, respectively) but also mean and minimum IC of the most suspicious area in heterogeneous lesions (AUC 0.983 and 0.992, respectively). Most RC fell within a range of low measured iodine values although a few had higher values. Conclusion: Automated iodine quantification maps reconstructed from clinical PCCT have a high diagnostic ability to differentiate RCs and neoplasms. The data from this pilot study can be used to help establish quantitative values for clinical differentiation of renal lesions.

Evaluating acidity levels in packaged coffee to enhance product label accuracy

Background:  Coffee is one of the world’s most popular beverages. Coffee is enjoyed for a variety of reasons, including its sensory characteristics. Some sensory characteristics of coffee, such as acidity, are attributed to the levels of various organic acids and chlorogenic acids present in the brew. The amount and composition of these organic acids are considered key factors that influence the acidity of the coffee. Many roasted coffee products on the market claim to be low in acid or even acid-free altogether. Objective:  The objective of this study was to evaluate the acidity of different packaged coffee products. Materials and Methods: All coffee samples were brewed using the drip method per preparation instructions for each product, and pH values for all samples were measured and recorded. Results:  Our results revealed a wide range of pH values among the tested products, with the highest pH value (pH 5.72) in sample XL96 and the lowest value (pH 4.97) in sample XL10. The pH values for the remainder of the samples ranged between (pH 5.0-5.29). The highest TDS was observed in sample XL10 with a value of (2.7%), and the lower TDS was in sample XL21 with a value of (1%). Conclusions: The results thus support the importance of creating a standard for the accurate label in the packaged coffee products. Keywords: Packaged coffee, coffee, acidity, roasting, label, hot brew, total solids

The Livestock Frontier in the Paraguayan Chaco: A Local Agent-based Perspective.

Deforestation is one of the most relevant transformations characterizing global environmental change in the tropics at present. There is wide consensus in pointing the context-dependent nature of tropical deforestation. In this sense, a better characterization of the phenomenon considering the social context could provide a more accurate picture of tropical deforestation. With this aim, a Q-methodology discourse analysis was conducted to characterise the different discourses that coexist in the particular region of the Paraguayan Chaco concerning the development of cattle ranching and derived deforestation. Four different discourses were identified as making sense the wide range of interests and values coexisting and clashing in the Paraguayan Chaco, namely: the Environmentalist discourse, the Business discourse, the Resigned discourse, and the Possibilist discourse. The results point that the fundamental differences between the discourses are largely explained by the different positions on three specific domains: (i) the socio-economic benefits the expansion of cattle ranching brings about; (ii) the environmental impacts the expansion of cattle ranching and the derived deforestation brings on; and, finally (iii) the degree to which an active intervention from the side of policy making to regulate the expansion of cattle ranching and to minimize possible detrimental effects is seen as necessary. The position of the different discourses in relation to these domains could help policy makers to make measures and regulations more widely accepted and followed.

Chronological, Petrogenetic, and Tectonic Significance of Paleoproterozoic Continental Crust within the North China Craton during the Global Tectono-Magmatic Lull

Abstract The 2.45–2.20 Ga period during the early Paleoproterozoic era is considered to have witnessed a global “Tectono-Magmatic Lull (TML)” and thus marks a relatively quiescent period. Our study unveils a 2.45–2.20 Ga magmatic suite from the Xiong’ershan area in the southern North China Craton, offering some key constraints on localized active tectonics during the TML. Zircon U-Pb dating shows Paleoproterozoic ages for the meta-basalt (2.31, 2.28 Ga), Na-rich meta-andesite (~2.33 Ga), tonalite-trondhjemite-granodiorite (TTG) gneisses (2.36, 2.30 Ga), K-rich granodiorite (~2.29 Ga), and monzogranite (2.33, 2.27 Ga). The meta-basalts geochemically and petrographically belong to calc-alkaline basalts and show distinctive Nb, Ta, and Ti contents and primitive mantle normalized patterns from different places in the Xiong’ershan area. Combined with their enriched εHf(t) values, the magmas were derived from subduction-related enriched mantle sources within a convergent plate boundary. The meta-andesites display high MgO content (average 4.5 wt%) and Mg# (44–57), strongly fractionated rare-earth pattern, calc-alkaline affinity, and negative Nb, Ta, and Ti anomalies. The TTG gneisses are of high SiO2 type (&amp;gt;62 wt%), high (La/Yb)N (17.5, 39.2), and Sr/Y (50.2, 104.3) and mostly display positive Eu anomalies and high-pressure type. Zircons from these rocks show a relatively narrow range of δ18O isotope values (5.35‰, 6.79‰) with εHf(t) isotope characteristics (−9.3, −3.3), suggesting derivation from partial melting of a thickened mafic lower crust. The youngest K-rich granodiorite and monzogranite show high K2O/Na2O ratios (0.65, 2.45). Variable molar ratio Al2O3/(CaO+Na2O+K2O) (A/CNK) and low zircon εHf(t) values suggest that the K-rich granitoids formed from the partial melting of different levels of crust. The presence of meta-basalt to andesite assemblages and diverse intermediate to felsic magmatic rocks implies magmatic activity within a convergent plate boundary tectonic environment with potential influence from plume-triggered extensional processes, supported by evidence of slab rollback and upwelling of mantle material.

Evaluation of the Vestibulo-ocular Reflex Using the Video Head Impulse Test in Patients with Unilateral Chronic Otitis Media.

To evaluate the vestibulo-ocular reflex (VOR) using the video head impulse test (vHIT) as a vestibular function assessment method in patients with unilateral chronic otitis media (COM). Twenty-eight patients with unilateral COM scheduled for middle ear surgery, including 12 males and 16 females with a mean age of 54.5 years, successfully underwent preoperative vHIT. vHIT variables, including VOR gain, VOR gain asymmetry, and the incidence of corrective saccades, were compared between the ipsilesional and contralesional ears. Ten (35.7%) patients reported varying degrees of disequilibrium or lightheadedness. The VOR gain in the ipsilesional and contralesional ears were 1.01 ± 0.10 and 1.04 ± 0.11, 0.97 ± 0.12 and 0.94 ± 0.13, and 0.97 ± 0.13 and 1.04 ± 0.15 in the horizontal canal (HC), anterior canal (AC), and posterior canal (PC), respectively. The average VOR gains in the ipsilesional ears were within the predefined range of normal values; however, the gains in HC and PC significantly decreased compared with those in contralesional ears (p=0.038 in HC and p=0.015 in PC). The prevalence of corrective saccades, including overt and/or covert saccades, did not differ significantly between the two ears. This study assessed the pathophysiology of the inner ear affected by chronic middle ear infection by quantitatively comparing the VOR using vHIT. It demonstrated that vHIT can be a practical assessment of vestibular function in patients with COM.

Artificial intelligence for characterization of diminutive colorectal polyps: A feasibility study comparing two computer-aided diagnosis systems

BACKGROUND Artificial intelligence (AI) has potential in the optical diagnosis of colorectal polyps. AIM To evaluate the feasibility of the real-time use of the computer-aided diagnosis system (CADx) AI for ColoRectal Polyps (AI4CRP) for the optical diagnosis of diminutive colorectal polyps and to compare the performance with CAD EYETM (Fujifilm, Tokyo, Japan). CADx influence on the optical diagnosis of an expert endoscopist was also investigated. METHODS AI4CRP was developed in-house and CAD EYE was proprietary software provided by Fujifilm. Both CADx-systems exploit convolutional neural networks. Colorectal polyps were characterized as benign or premalignant and histopathology was used as gold standard. AI4CRP provided an objective assessment of its characterization by presenting a calibrated confidence characterization value (range 0.0-1.0). A predefined cut-off value of 0.6 was set with values &lt; 0.6 indicating benign and values ≥ 0.6 indicating premalignant colorectal polyps. Low confidence characterizations were defined as values 40% around the cut-off value of 0.6 (&lt; 0.36 and &gt; 0.76). Self-critical AI4CRP’s diagnostic performances excluded low confidence characterizations. RESULTS AI4CRP use was feasible and performed on 30 patients with 51 colorectal polyps. Self-critical AI4CRP, excluding 14 low confidence characterizations [27.5% (14/51)], had a diagnostic accuracy of 89.2%, sensitivity of 89.7%, and specificity of 87.5%, which was higher compared to AI4CRP. CAD EYE had a 83.7% diagnostic accuracy, 74.2% sensitivity, and 100.0% specificity. Diagnostic performances of the endoscopist alone (before AI) increased non-significantly after reviewing the CADx characterizations of both AI4CRP and CAD EYE (AI-assisted endoscopist ). Diagnostic performances of the AI-assisted endoscopist were higher compared to both CADx-systems, except for specificity for which CAD EYE performed best. CONCLUSION Real-time use of AI4CRP was feasible. Objective confidence values provided by a CADx is novel and self-critical AI4CRP showed higher diagnostic performances compared to AI4CRP.

The Resorcinarene Hexameric Capsule as a Supramolecular Photoacid to Trigger Olefin Hydroarylation in Confined Space.

The self-assembled resorcinarene capsule C6 shows remarkable photoacidity upon light irradiation, which is here exploited to catalyze olefin hydroarylation reactions in confined space. An experimental pKa* value range of -3.3--2.8 was estimated for the photo-excited hexameric capsule C6 *, and consequently an increase in acidity of 8.8 log units was observed with respect to its ground state (pKa=5.5-6.0). This makes the hexameric capsule the first example of a self-assembled supramolecular photoacid. The photoacid C6 * can catalyze hydroarylation reaction of olefins with aromatic substrates inside its cavity, while no reaction occurred between them in the absence of irradiation and/or capsule. DFT calculations corroborated a mechanism in which the photoacidity of C6 * plays a crucial role in the protonation step of the aromatic substrate. A further proton transfer to olefin with a concomitant C-C bond formation and a final deprotonation step lead to product releasing.

MineCam: Application of Combined Remote Sensing and Machine Learning for Segmentation and Change Detection of Mining Areas Enabling Multi-Purpose Monitoring

Our study addresses the need for universal monitoring solutions given the diverse environmental impacts of surface mining operations. We present a solution combining remote sensing and machine learning techniques, utilizing a dataset of over 2000 satellite images annotated with ten distinct labels indicating mining area components. We tested various approaches to develop comprehensive yet universal machine learning models for mining area segmentation. This involved considering different types of mines, raw materials, and geographical locations. We evaluated multiple satellite data set combinations to determine optimal outcomes. The results suggest that radar and multispectral data fusion did not significantly improve the models’ performance, and the addition of further channels led to the degradation of the metrics. Despite variations in mine type or extracted material, the models’ effectiveness remained within an Intersection over Union value range of 0.65–0.75. Further, in this research, we conducted a detailed visual analysis of the models’ outcomes to identify areas requiring additional attention, contributing to the discourse on effective mining area monitoring and management methodologies. The visual examination of models’ outputs provides insights for future model enhancement and highlights unique segmentation challenges within mining areas.

Diagenetic evolution of secondary evaporites and associated host-rock dolostones in the Huron Domain (Michigan Basin): insights from petrography, geochemistry, and C-O-S-Sr isotopes

ABSTRACT In this study, we present a detailed investigation of C-O-S-Sr isotope systematics and elemental analysis of secondary sulfates and associated host-rock carbonates of Cambrian to Devonian sedimentary successions along the eastern flank of the Michigan Basin, Ontario. This study evaluates the diagenetic evolution of pore fluids and their sources in fracture-fill and replacement sulfate minerals in low-permeability carbonate units in the Michigan Basin. Secondary sulfates, represented by gypsum and anhydrite, contain various petrographic types, represented by vug- and fracture-filling fibrous anhydrite in the Cambrian (δ18O vary between 16.8 to 17.6‰ VPDB and δ34S 28.3 to 29.0‰ CDT, 87Sr/86Sr ratios vary from 0.70834 to 0.70991, respectively) and Ordovician fibrous anhydrite (δ18O 16.8‰, δ34S 28.2‰, 87Sr/86Sr ratios 0.70829). These phases display mainly uniform REE patterns with Y/Ho and Zr/Hf ratios, flat La*, Gd*, and Y*, and enriched LREEs. In the Silurian strata, idiotopic satin-spar δ18O values vary between 4.0 and 8.3‰, δ34S 23.4 and 31.4‰ with 87Sr/86Sr ratios 0.70816–0.70866, xenotopic porphyroblast gypsum δ18O values vary between 4.5 and 13.3‰, δ34S 22.6 to 33.1‰, with 87Sr/86Sr ratios of 0.70850–0.70880, alabastrine gypsum δ18O values vary between 4.2 and 11.7‰, δ34S 23.1 to 26.9‰, with 87Sr/86Sr ratios of 0.70816–0.70876 and felted anhydrite δ18O values of 11.1‰, δ34S 27.4‰, with a 87Sr/86Sr ratio of 0.70849. These geochemical proxies suggest a comparable sulfate-rich source for both age groups under similar geochemical conditions. Gypsum in the Silurian Salina Group displays a wide range of REE values with Y/Ho, and Zr/Hf ratios, Nd/YbN and Pr/YbN, flat to strong Ce/Ce*, and a flat to strong Eu/Eu* anomaly, Gd/LaN, Tb/LaN, and Sm/LaN. These sulfates formed at burial from fluids of variable isotope compositions, chemical compositions, and temperatures. The sources of these fluids range from brines migrating from a deeper part of the basin forming anhydrite in the Cambrian and Ordovician sequences which were also affected by dolomitization and later hydrothermal fluid influx, to rehydration of gypsum at shallower burial depths and affected by salt dissolution and incursion of meteoric water during and following the Alleghenian orogeny.