Case series of retinal vein occlusions showing early recovery using oral l-methylfolate.

This case series describes the aggregate rate of recovery in five consecutive subjects (six eyes) with retinal vein occlusion (RVO) who received l-methylfolate and other vitamins via Ocufolin®, a medical food. Subjects were followed for 10-33 months by a single ophthalmologist. Ocufolin® was prescribed at the time of diagnosis and subjects remained on the regimen throughout the time of observation. Examinations were performed in an un-masked fashion at 3-month intervals with recording of best corrected visual acuity (BCVA), average retinal nerve fiber layer (ARNFL) and central macular thickness (CMT), and fundus (examination of the retina, macula, optic nerve, and vessels) photography. Testing was done for vitamin deficiencies, vascular and coagulable risk factors, and methylenetetrahydrofolate reductase (MTHFR) polymorphisms. Vitamin deficiencies and vascular risk factors were found in all subjects, and all four tested subjects carried at least one MTHFR polymorphism. By the end of the study period BCVA in all subjects was 20/25 or better. Cystoid macular edema was identified and measured by optical coherence tomography (OCT). The percent change was calculated and plotted at 3-month intervals using the percent change in thickness from the time of diagnosis and percent change toward normative values for ARNFL and CMT. The total reduction in thickness of ARNFL and CMT from time of diagnosis was 44.19% and 30.27%, respectively. The comparison to normative data shows a reduction of ARNFL from 164.2% to 94% and CMT from 154.4% to 112.7% of normal thickness (100%). Plots showed the aggregate recovery was most rapid over the first 3 months and slowed over the next 3 months with most of the recovery taking place within 6 months of treatment. The rate of improvement in BCVA and resolution of retinal thickening was found to be better than predicted on historical grounds. No subjects progressed from nonischemic to ischemic RVO. Vitamin deficiencies, vascular risk factors, and genetic predisposition to oxidative stress were common in this RVO series. It appears that addressing these factors with Ocufolin® had a salutary effect on recovery.

Prioritizing water availability study settings to address geogenic contaminants and related societal factors.

Water availability for human and ecological uses depends on both water quantity and water quality. The U.S. Geological Survey (USGS) is developing strategies for prioritizing regional-scale and watershed basin-scale studies of water availability across the nation. Previous USGS ranking processes for basin-scale studies incorporated primarily water quantity factors but are now considering additional water quality factors. This study presents a ranking based on the potential impacts of geogenic constituents on water quality and consideration of societal factors related to water quality. High-concentration geogenic constituents, including trace elements and radionuclides, are among the most prevalent contaminants limiting water availability in the USA and globally. Geogenic constituents commonly occur in groundwater because of subsurface water-rock interactions, and their distributions are controlled by complex geochemical processes. Geogenic constituent mobility can also be affected by human activities (e.g., mining, energy production, irrigation, and pumping). Societal factors and relations to drinking water sources and water quality information are often overlooked when evaluating research priorities. Sociodemographic characteristics, data gaps resulting from historical data-collection disparities, and infrastructure condition/age are examples of factors to consider regarding environmental justice. This paper presents approaches for ranking and prioritizing potential basin-scale study areas across the contiguous USA by considering a suite of conventional physical and geochemical variables related to geogenic constituents, with and without considering variables related to societal factors. Simultaneous consideration of societal and conventional factors could provide decision makers with more diverse, interdisciplinary tools to increase equity and reduce bias in prioritizing focused research areas and future water availability studies.

Estimating Lithium Concentrations in Groundwater Used as Drinking Water for the Conterminous United States.

Lithium (Li) concentrations in drinking-water supplies are not regulated in the United States; however, Li is included in the 2022 U.S. Environmental Protection Agency list of unregulated contaminants for monitoring by public water systems. Li is used pharmaceutically to treat bipolar disorder, and studies have linked its occurrence in drinking water to human-health outcomes. An extreme gradient boosting model was developed to estimate geogenic Li in drinking-water supply wells throughout the conterminous United States. The model was trained using Li measurements from ∼13,500 wells and predictor variables related to its natural occurrence in groundwater. The model predicts the probability of Li in four concentration classifications, ≤4 µg/L, >4 to ≤10 µg/L, >10 to ≤30 µg/L, and >30 µg/L. Model predictions were evaluated using wells held out from model training and with new data and have an accuracy of 47-65%. Important predictor variables include average annual precipitation, well depth, and soil geochemistry. Model predictions were mapped at a spatial resolution of 1 km2 and represent well depths associated with public- and private-supply wells. This model was developed by hydrologists and public-health researchers to estimate Li exposure from drinking water and compare to national-scale human-health data for a better understanding of dose-response to low (<30 µg/L) concentrations of Li.

Multispectral multibeam backscatter response of heterogeneous rhodolith beds.

Acoustic backscatter has been used as a tool to map the seafloor in greater detail and plays an increasingly important role in seafloor mapping to meet multiple ocean management needs. An outstanding challenge to the use of backscatter for seafloor mapping is the distinction between acoustically similar substrates, such as mixed sediments from rhodoliths. Rhodolith beds are a biogenic substrate that provides important ecological services, and are typically classified as a single categorical substrate type-though nodules coverage may be spatially variable. Recently, multispectral acoustic backscatter has demonstrated great potential to improve thematic seafloor mapping compared to single-frequency systems. This work employs multispectral multibeam backscatter and underwater imagery to characterize and map rhodolith beds in the Costa das Algas Marine Protected Area (Brazil). A support vector machine classifier was used to classify multifrequency backscatter mosaics according to rhodolith classes identified from underwater imagery. Results suggest that multispectral backscatter is effective both in providing information for mapping different proportions of rhodolith coverage and in predicting the presence or absence of these nodules. The backscatter of the lowest frequency was the most useful for distinguishing variable proportions of rhodolith coverage, and the two higher frequencies were better predictors of presence and absence.

Environmental and economic impacts of retrieved abandoned, lost, and discarded fishing gear in Southwest Nova Scotia, Canada.

Abandoned, lost, and discarded fishing gear (ALDFG), negatively impacts marine environments. Managing ALDFG in Atlantic Canada is challenging due to knowledge gaps on loss rates, locations, data availability/accuracy, impacts, and regulatory barriers for retrieval. This study removed ALDFG in Southwest Nova Scotia in collaboration with local fishers (with local knowledge and practical ALDFG removal expertise), government, non-profit organizations, and academia. A total of 29,298 kg of ALDFG was retrieved, including 24,630 kg using towed grapples covering ~3986 km of seafloor and 4668 kg from shorelines (comprising, 68 % lobster traps and 12 % dragger cable by weight). Traps ranged from <1 to 37 years old (median, 10 years). Traps continued to catch target and non-target species with 25 species released, including 652 individual lobsters (82 % were market-sized) and 57 fish (42 were species-at-risk). Based on estimated 2 % trap losses, annual commercial losses from ALDFG were $155,836 CAD in Lobster Fishing Area 34.

Retrieval of abandoned, lost, and discarded fishing gear in Southwest Nova Scotia, Canada: Preliminary environmental and economic impacts to the commercial lobster industry.

Southwest Nova Scotia (SWNS) is Canada's most productive lobster (Homarus americanus) fishing region. Abandoned, lost, and discarded fishing gear (ALDFG) is widespread. This baseline study provides the first preliminary assessment of environmental and economic impacts of ALDFG on the commercial lobster industry in SWNS. Fishers conducted 60 retrieval trips, searched ~1523 km2 of the seafloor and removed 7064 kg of ALDFG (comprising 66% lobster traps and 22% dragger cable). Results showed that lost traps continued to capture target and non-target species until gear degraded. A total of 15 different species were released from retrieved ALDFG, including 239 lobsters (67% were market-sized) and seven groundfish (including five species-at-risk). The present findings, combined with information on regional fishing effort and market prices, estimate that commercial losses from ALDFG can exceed $175,000 CAD annually. This baseline assessment provides useful data for government and commercial fishing stakeholders to improve ALDFG management.

Machine-Learning Predictions of High Arsenic and High Manganese at Drinking Water Depths of the Glacial Aquifer System, Northern Continental United States.

Globally, over 200 million people are chronically exposed to arsenic (As) and/or manganese (Mn) from drinking water. We used machine-learning (ML) boosted regression tree (BRT) models to predict high As (>10 µg/L) and Mn (>300 µg/L) in groundwater from the glacial aquifer system (GLAC), which spans 25 states in the northern United States and provides drinking water to 30 million people. Our BRT models' predictor variables (PVs) included recently developed three-dimensional estimates of a suite of groundwater age metrics, redox condition, and pH. We also demonstrated a successful approach to significantly improve ML prediction sensitivity for imbalanced data sets (small percentage of high values). We present predictions of the probability of high As and high Mn concentrations in groundwater, and uncertainty, at two nonuniform depth surfaces that represent moving median depths of GLAC domestic and public supply wells within the three-dimensional model domain. Predicted high likelihood of anoxic condition (high iron or low dissolved oxygen), predicted pH, relative well depth, several modeled groundwater age metrics, and hydrologic position were all PVs retained in both models; however, PV importance and influence differed between the models. High-As and high-Mn groundwater was predicted with high likelihood over large portions of the central part of the GLAC.

Machine Learning Predictions of pH in the Glacial Aquifer System, Northern USA.

A boosted regression tree model was developed to predict pH conditions in three dimensions throughout the glacial aquifer system of the contiguous United States using pH measurements in samples from 18,386 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials strongly controls pH and, when coupled with long flowpaths, results in the most alkaline conditions. Conversely, in areas where glacial sediments are thin and carbonate-poor, pH conditions remain acidic. At depths typical of drinking-water supplies, predicted pH >7.5-which is associated with arsenic mobilization-occurs more frequently than predicted pH <6-which is associated with water corrosivity and the mobilization of other trace elements. A novel aspect of this model was the inclusion of numerically based estimates of groundwater flow characteristics (age and flowpath length) as predictor variables. The sensitivity of pH predictions to these variables was consistent with hydrologic understanding of groundwater flow systems and the geochemical evolution of groundwater quality. The model was not developed to provide precise estimates of pH at any given location. Rather, it can be used to more generally identify areas where contaminants may be mobilized into groundwater and where corrosivity issues may be of concern to prioritize areas for future groundwater monitoring.

Fluoride occurrence in United States groundwater.

Data from 38,105 wells were used to characterize fluoride (F) occurrence in untreated United States (U.S.) groundwater. For domestic wells (n = 11,032), water from which is generally not purposely fluoridated or monitored for quality, 10.9% of the samples have F concentrations >0.7 mg/L (U.S. Public Health Service recommended optimal F concentration in drinking water for preventing tooth decay) (87% are <0.7 mg/L); 2.6% have F > 2 mg/L (EPA Secondary Maximum Contaminant Level, SMCL); and 0.6% have F > 4 mg/L (EPA MCL). The data indicate the biggest concern with F in domestic wells at the national scale could be one of under consumption of F with respect to the oral-health benchmark (0.7 mg/L). Elevated F concentrations relative to the SMCL and MCL are regionally important, particularly in the western U.S. Statistical comparisons of potentially important controlling factors in four F-concentration categories (<0.1-0.7 mg/L; >0.7-2 mg/L; >2-4 mg/L; >4 mg/L) at the national scale indicate the highest F-concentration category is associated with groundwater that has significantly greater pH values, TDS and alkalinity concentrations, and well depths, and lower Ca/Na ratios and mean annual precipitation, than the lowest F-concentration category. The relative importance of the controlling factors appears to be regionally variable. Three case studies illustrate the spatial variability in controlling factors using groundwater-age (groundwater residence time), water-isotope (evaporative concentration), and water-temperature (geothermal processes) data. Populations potentially served by domestic wells with F concentrations <0.7, >0.7, >2, and >4 mg/L are estimated to be ~28,200,000, ~3,110,000; ~522,000; and ~172,000 people, respectively, in 40 principal aquifers with at least 25 F analyses per aquifer.

Benthic marine debris in the Bay of Fundy, eastern Canada: Spatial distribution and categorization using seafloor video footage.

Marine debris, particularly plastic and abandoned, lost and discarded fishing gear, is ubiquitous in marine environments. This study provides the first quantitative and qualitative assessment of benthic debris using seafloor video collected from a drop camera system in the Bay of Fundy, Eastern Canada. An estimated 137 debris items km-2 of seafloor were counted, comprising of plastic (51%), fishing gear (including plastic categories; 28%) and other (cable, metal, tires; 21%). Debris was widespread, but mainly located nearshore (within 9 km) and on the periphery of areas with high fishing intensity. This baseline benthic marine debris characterization and estimate of abundance provides valuable information for government (municipal, provincial and federal) and for other stakeholders to implement management strategies to reduce plastic and other categories of benthic marine pollution at source. Strategies may include limiting plastic use and reducing illegal dumping through improved education among fishers.

Comparing Selections of Environmental Variables for Ecological Studies: A Focus on Terrain Attributes.

Selecting appropriate environmental variables is a key step in ecology. Terrain attributes (e.g. slope, rugosity) are routinely used as abiotic surrogates of species distribution and to produce habitat maps that can be used in decision-making for conservation or management. Selecting appropriate terrain attributes for ecological studies may be a challenging process that can lead users to select a subjective, potentially sub-optimal combination of attributes for their applications. The objective of this paper is to assess the impacts of subjectively selecting terrain attributes for ecological applications by comparing the performance of different combinations of terrain attributes in the production of habitat maps and species distribution models. Seven different selections of terrain attributes, alone or in combination with other environmental variables, were used to map benthic habitats of German Bank (off Nova Scotia, Canada). 29 maps of potential habitats based on unsupervised classifications of biophysical characteristics of German Bank were produced, and 29 species distribution models of sea scallops were generated using MaxEnt. The performances of the 58 maps were quantified and compared to evaluate the effectiveness of the various combinations of environmental variables. One of the combinations of terrain attributes-recommended in a related study and that includes a measure of relative position, slope, two measures of orientation, topographic mean and a measure of rugosity-yielded better results than the other selections for both methodologies, confirming that they together best describe terrain properties. Important differences in performance (up to 47% in accuracy measurement) and spatial outputs (up to 58% in spatial distribution of habitats) highlighted the importance of carefully selecting variables for ecological applications. This paper demonstrates that making a subjective choice of variables may reduce map accuracy and produce maps that do not adequately represent habitats and species distributions, thus having important implications when these maps are used for decision-making.

Preservation of retinal structure and function after cilioretinal artery occlusion: a case report.

Cilioretinal artery occlusion is a cause of sudden, often catastrophic loss of central vision. There are no established effective treatments. Recently, a patient presented 24 hours after a cilioretinal artery occlusion, following a cardiac catheterization prior to which her blood thinners had been discontinued. Lacking an effective way to address the severe retinal ischemic oxidative stress, she was offered, under compassionate use, a multivitamin complex designed to address retinal ischemia and oxidative stress. Significant components of this product are L-methylfolate and n-acetyl cysteine. The patient experienced a rapid unexpected improvement in vision and preservation of retinal structure, suggesting that marked improvement in retinal artery occlusions outcomes may be possible as late as 24 hours postocclusion. This is the third reported case of cilioretinal artery occlusion associated with cardiac catheterization.

Vitamin D deficiency and posterior subcapsular cataract.

PURPOSE: To evaluate risk factors associated with posterior subcapsular cataract (PSC) development and the relationship between vitamin D deficiency and etiology of PSC. METHODS: Of 195 consecutive patients from a private ophthalmology practice, diagnosed with PSC, serum vitamin D3 (25-OH D) levels were obtained for 175, and associations among risk factors, comorbidities, and PSC were assessed. RESULTS: In all 175 PSC patients, mean 25-OH D levels were low (24 ng/mL ±11 SD) compared with age/sex-matched standards. Significant differences in 25-OH D levels were noted between PSC subjects taking/not taking calcium supplements, systemic steroids, osteoporosis medications, etc. Alone, smoking status and calcium channel blockers and/or topical steroids use made no significant difference in PSC subjects 25-OH D levels, but two or more of these factors were associated with lowered levels of 25-OH D (P<0.001). Low vitamin D was correlated with female sex, autoimmune disease, and non-skin cancer diagnosis, but not with age, or other comorbidities or medication use. In five early-stage PSC patients taking 5,000 IU of 25-OH D daily for vitamin D deficiency, there was resolution of their cataracts during the 2-year follow-up period. CONCLUSION: Vitamin D levels for most PSC patients fell below the 30 ng/mL calcium homeostasis threshold. Some comorbidities and non-ophthalmic interventions are associated with the development of PSC at less depressed levels of 25-OH D. In this series, vitamin D deficiency was associated with PSC cataract, suggesting that raising the level of vitamin D intake may reduce PSC incidence.

Trace metal contamination of Beaufort's Dyke, North Channel, Irish Sea: a legacy of ordnance disposal.

Beaufort's Dyke is a disused ordnance disposal ground within the North Channel of the Irish Sea. Over 1 million tonnes of ordnance were disposed of in the dyke over a 40 year period representing a substantial volume of trace metal pollutants introduced to the seabed. Utilising particle transport modelling software we simulated the potential transport of metal particles from Beaufort's Dyke over a 3 month period. This demonstrated that Beaufort's Dyke has the potential to act as a source for trace metal contamination to areas beyond the submarine valley. Trace metal analysis of sediments from the Dyke and surrounding National Marine Monitoring Programme areas demonstrate that the Dyke is not the most contaminated site in the region. Particle transport modelling enables the transport pathways of trace metal contaminants to be predicted. Implementation of the technique in other munitions disposal grounds will provide valuable information for the selection of monitoring stations.

Epifaunal colonization of the Loch Linnhe artificial reef: influence of substratum on epifaunal assemblage structure.

A one-year study was carried out off the west coast of Scotland to compare the epifaunal colonization of concrete material used in the construction of the Loch Linnhe artificial reef with that on four other types of artificial substrata (preservative treated wood, rubber, steel and PVC). Settlement panels made from each of the materials were submerged in a vertical orientation during four seasonal exposure periods. There were clear seasonal trends across the four exposure periods with higher epifaunal biodiversity on all types of panel in the spring and summer exposure periods. Epifaunal assemblage structure was significantly different between the five types of material after each three-month exposure period. Concrete, preservative treated wood and PVC tended to have the highest species diversities. A successional study was also carried out. Over a 12-month exposure period epifaunal biodiversity increased on all five materials. After 12 months of exposure, the epifaunal assemblage structure was still significantly different between materials but had become more similar indicating a successional change towards a stable assemblage on all panels. The results indicate that material type and season have a significant effect on epifaunal assemblage structure after short (three-month) periods of submersion but that these effects are reduced with increasing length of exposure. The study concludes that the choice of construction material for an artificial reef will have little effect on the long-term epifaunal community structure, as long as the material is physically stable, non-toxic and offers a high degree of habitat complexity.