Total Content Research Articles

Circulating 25-hydroxycholecalciferol and calcium levels, and alkaline phosphatase activity among people living with and without human immunodeficiency virus and injecting drugs in kenya

Background People who inject drugs (PWID) and living with the human immunodeficiency virus (PLHIV) are at higher risk of suffering marked derangements in micronutrient levels, leading to poor disease and treatment outcomes. Consequently, this can be monitored by measuring key biomarkers, such as total circulating (serum) 25-hydroxycholecalciferol (25(OH)D3), calcium, and alkaline phosphatase (ALP) for timely intervention. Therefore, circulating levels of 25(OH)D3 and calcium, and ALP activity were determined in PWID and are highly active anti-retroviral treatment (HAART)-experienced or -naive, along with those without HIV infection.MethodsThis cross-sectional study compared serum concentrations of 25(OH)D3, calcium, and ALP in Kenyan PLHIV and were HAART-naive (n = 30) or -experienced (n = 61), PWID and without HIV (n = 132).Results Circulating 25(OH)D3 levels were significantly different amongst the study groups (P < 0.001), and were significantly lower in the HAART-experienced (median, 17.3; IQR, 18.3 ng/ml; P < 0.001) and -naive participants (median, 21.7; IQR, 12.8 ng/ml; P = 0.015) relative to uninfected (median, 25.6; IQR, 6.8 ng/ml) PWID. In addition, the proportions of vitamin D deficiency (55.7%, 40.0%, and 17.4%) and insufficiency (31.1%, 53.3%, and 63.6%) compared to sufficiency (13.1%, 6.7%, and 18.9%; P < 0.001) were greater amongst HAART-experienced, -naive, and uninfected study groups, respectively. Likewise, serum total calcium concentrations were lower in the HAART-experienced relative to HIV-negative (P = 0.019) individuals. Serum ALP activity was also lower in the HAART-experienced in contrast to HIV-negative PWID (P = 0.048). Regression analysis indicated that predictors of circulating 25(OH)D3 were: age (β = 0.287; R2 = 8.0%; P = 0.017) and serum ALP (β = 0.283; R2 = 6.4%; P = 0.033) in the HAART-experienced PWID, and serum ALP (β = 0.386; R2 = 14.5%; P < 0.001) in the HIV-negative PWID.Conclusion This study suggests that HIV-1 infection and HAART, including injection substance use, decrease circulating 25(OH)D3, calcium and ALP activity. In addition, age and ALP activity are associated with low circulating vitamin D levels in HAART-experienced PWID. The results highlight the importance of incorporating vitamin D and calcium supplementation in treatment and rehabilitation protocols for PLHIV.

Oxidative stress and type 2 diabetes: the development and the pathogenesis, Jordanian cross-sectional study

Accumulation of reactive oxygen species (ROS) can disrupt the antioxidant defense system, leading to oxidative stress that leads to pathological damage to vital human organs, including hormone-producing glands. Normal physiological function is subsequently disrupted and disorders such as Type 2 Diabetes Mellitus (T2DM) may develop. The critical role of the antioxidant defense system in counteracting ROS and mitigating oxidative stress is fundamental to understanding the pathogenesis of T2DM. In our study, we monitored the oxidant/antioxidant status in a selected Jordanian population to further elucidate this relationship. Our results show higher serum levels of Malondialdehyde (MDA); 0.230 ± 0.05 and 0.207 ± 0.06 μmol/l for the diabetic and the obese groups, respectively, relative to 0.135 ± 0.04 μmol/l for the non-obese healthy group. Lower activity of Catalase (CAT) was recorded among the diabetic (9.2 ± 3.2) and obese groups (11.0 ± 2.8), compared to the non-obese healthy group (12.1 ± 3.5). Significant elevations (P < 0.05) were observed in uric acid concentrations in diabetic and obese subjects: 451 ± 57 mg/dl and 430 ± 51, respectively, versus 342 ± 57 mg/dl in the non-obese healthy group. Moreover, no significant differences were obtained between all the studied groups for the serum albumin and total protein concentrations. Our findings demonstrate the potential role of oxidative stress in the development and occurrence of T2DM.

Phytoremediation Characterization of Heavy Metals by Some Native Plants at Anthropogenic Polluted Sites in Jeddah, Saudi Arabia

Many anthropogenic activities have lately resulted in soil adulteration by heavy metals (HMs). The assessment of native plant species that grow in the polluted environments is of great importance for using these plants in phytoremediation techniques. This study was conducted in three industrial regions in Jeddah city, Wadi Marik, Bahra, and Khumrah, to assess the HM contamination level in them. This study also evaluated the phytoremediation ability of nine plant species collected from the studied regions. Soil physicochemical properties of the studied sites were investigated. Nine HMs, aluminum (Al), nickel (Ni), zinc (Zn), cobalt (Co), iron (Fe), lead (Pb), manganese (Mn), chromium (Cr), and barium (Ba), have been evaluated in the collected soil, plant shoots, and root samples. Total thiol concentration in the plant shoots and roots was determined. The phytoremediation indexes, such as bioaccumulation factor (BCF) and translocation factor (TF), were estimated. The results show that the soil of all the explored sites was sandy and slightly alkaline. It was found that Ni, Pb, and Cr were above the international permissible limit in all soil samples. The Wadi Marik region recorded the highest HM concentration compared to the other sites. In the Bahra region, Fe, Zn, Co, and Mn in all collected soil samples were below internationally permissible levels. In Khumrah, the highest concentration of Zn was found in the soil sample collected around F. indica plants, while Fe, Co, and Mn in all collected soil samples were below the international permissible limit. Depending on the BCF calculations, most of the investigated species showed phytostabilization ability for most of the studied HMs. Of them, E. indica, T. nubica, and P. divisum recorded the highest BCF values that ranged from 16.1 to 3.4. The BCF values of the studied HMs reduced in the order of Cr &gt; Zn &gt; Mn &gt; Co &gt; Ba &gt; Fe &gt; Al &gt; Pb. Phytoextration of Co and Cr could be achieved by P. oleracea and F. indica, which showed TF values that reached 6.7 and 6.1, respectively. These plants showed high potential for phytoremediation and can be suggested as protective belts close to the contaminated regions of Jeddah.

Investigating the carcinogenic and non-carcinogenic health hazards of heavy metal ions in Spinacia oleracea grown in agricultural soil treated with biochar and humic acid.

This study addressed the bioaccumulation and human health risk among the consumption of Spinacia oleracea grown in agricultural soil treated with humic acid (189-2310ppm) and biochars (0.00-5.10%.wt). The biochars came from two local feedstocks of rice-husk (RH) and sugar-beet-pulp (SBP) pyrolyzed at temperatures 300 and 600°C. Total concentrations of Cu, Cd, and Ni found in both the soil and biomass/biochar exceeded global safety thresholds. The bioaccumulation levels of HMs in spinach leaves varied, with Fe reaching the highest concentration at 765.27mgkg-1 and Cd having the lowest concentration at 3.31mgkg-1. Overall, the concentrations of Zn, Cd, Pb, and Ni in spinach leaves exceeded the safety threshold limits, so that its consumption is not recommended. The assessment of hazard quotient (HI) for the HMs indicated potential health hazards for humans (HI > 1) from consuming the edible parts of spinach. The biochar application rates of 4.35%wt and 0.00%.wt resulted in the highest (3.69) and lowest (3.15) HI values, respectively. The cumulative carcinogenic risk (TCR) ranged from 0.0085 to 0.0119, exceeding the cancer risk threshold. Introducing 5.10%wt biomass/biochar resulted in a 36% rise in TCR compared to the control. The utilization of humic acid alongside HMs-polluted biochars results in elevated levels of HMs bioaccumulation exceeding the allowable thresholds in crops (with a maximum increase of 49% at 2000ppm humic acid in comparison to 189ppm). Consequently, this raised the HI by 46% and the TCR by 22%. This study demonstrated that the utilization of HMs-polluted biochars could potentially pose supplementary health hazards. Moreover, it is evident that the utilization of HMs-polluted biochars in treating metal-contaminated soil does not effectively stabilize or reduce pollution.

Climate change triggered planktonic cyanobacterial blooms in a regulated temperate river

Harmful algae blooms are a rare phenomenon in rivers but seem to increase with climate change and river regulation. To understand the controlling factors of cyanobacteria blooms that occurred between 2017 and 2020 over long stretches (> 250 km) of the regulated Moselle River in Western Europe, we measured physico-chemical and biological variables and compared those with a long-term dataset (1997–2016). Cyanobacteria (Microcystis) dominated the phytoplankton community in the late summers of 2017–2020 (cyano-period) with up to 110 µg Chlorophyll-a/L, but had not been observed in the river in the previous 20 years. From June to September, the average discharge in the Moselle was reduced to 69–76% and water temperature was 0.9–1.8 °C higher compared to the reference period. Nitrogen (N), phosphorus (P) and silica (Si) declined since 1997, albeit total nutrient concentrations remained above limiting conditions in the study period. Cyanobacterial blooms correlated best with low discharge, high water temperature and low nitrate. We conclude that the recent cyanobacteria blooms have been caused by dry and warm weather resulting in low flow conditions and warm water temperature in the regulated Moselle. Under current climate projections, the Moselle may serve as an example for the future of regulated temperate rivers.

Tunable gelatin methacrylate polyethylene glycol diacrylate hydrogels for cell mechanosensing applications

Three-dimensional (3D) tissue-engineered scaffolds mimic the physiological environment of cells by providing essential structural support, biochemical cues, and the mechanical strength needed for cell adhesion, proliferation, migration, and differentiation. Hydrogels like polyethylene glycol diacrylate (PEGDA) are commonly used biomaterials for cell culture due to their affordability, tunable stiffness, and ability to efficiently transport nutrients and gases. However, PEGDA lacks cell adhesion sites essential for cell proliferation and migration and has limited degradability. Methacrylated gelatin (GelMA) produced from denatured bovine collagen, crosslinks under ultraviolet light (UV) resulting in a degradable hydrogel with cell adhesion sites. Here, we synthesized GelMA with variable degree of methacrylation and crosslinked it with PEGDA to produce cell scaffolds with independently tunable mechanical and biochemical properties by varying the ratios of the two polymers. We determined polymer ratios that resulted in scaffolds with different mechanical properties but the same gelatin concentrations (providing cell adhesion and degradation sites) as well as different gelatin concentrations but the same mechanical properties. With the developed scaffold library, we further used a design of experiments approach to probe the parameter space and perform detailed analysis on chemical composition-scaffold properties as well as scaffold properties-cell behavior correlations. Our findings showed that hydrogel properties such as modulus, swelling, pore size, and permeability, strongly depended on total polymer concentration and not on the GelMA fraction. GelMA significantly influenced cell spreading, while addition of any amount of PEGDA delayed cell spreading significantly. We suggest that such analysis will broaden the utility of the GelMA/PEGDA hydrogels, presenting a versatile platform for mechanosensing research in 3D environments.

The occurrence and human health risk assessment of total and aflatoxin B1 in selected food commodities in Bhutan

Aflatoxins are mycotoxins that contaminate staple foods globally and pose a significant health risk. To the best of our knowledge, information on the occurrence of aflatoxins in Bhutanese diets is scarce. This study aimed to estimate the aflatoxin levels in selected foodstuffs in Bhutan and determine the health risk associated with aflatoxin exposure. Ten different types of food commodities were randomly collected from farmers’ markets, shelves of supermarkets, and wholesale and retail shops from 20 districts of the country. The samples were subjected to analysis by an enzyme-linked immunosorbent assay for both total aflatoxins (B1, B2, G1 and G2) and aflatoxin B1. Among the 315 samples included, 48.81% and 79.35% were positive for total aflatoxins and aflatoxin B1, respectively. The overall mean total aflatoxin concentration was 11.49 ± 12.83 µg/kg, and that for B1 was 17.62 ± 23.99 µg/kg. The most prevalent food commodity with the highest aflatoxin contamination was chili products. In addition, the estimated daily intake and margin of exposure to aflatoxin B1 via the consumption of chili products ranged from 0.98 to 5.34 ng kg−1 bw day−1 and from 74.90 to 408.10, indicating a risk for public health. The liver cancer risk was estimated to be 0.01 and 0.007 cancers per year per 100,000 population resulting from the consumption of chili products. The present findings revealed the presence of total aflatoxins and aflatoxin B1 in the selected samples. The margin of exposure values was exorbitant, demanding a stringent public health measure. Notably, these results suggest the need for routine monitoring of aflatoxin contamination in the region and stress rigorous safety management strategies to reduce exposure.

Evaluation of Exposure to Bisphenol Analogs through Canned and Ready-to-Eat Meal Consumption and Their Possible Effects on Blood Pressure and Heart Rate

Bisphenols are endocrine-disrupting chemicals used in plastics and resins for food packaging. This study aimed to evaluate the exposure to bisphenol A (BPA), bisphenol S (BPS), and bisphenol F (BPF) associated with the consumption of fresh, canned, and ready-to-eat meals and determine the effects of bisphenols on blood pressure and heart rate. Forty-eight healthy young adults were recruited for this study, and they were divided into the following three groups: fresh, canned, and ready-to-eat meal groups. Urine samples were collected 2, 4, and 6 h after meal consumption, and blood pressure and heart rate were measured. The consumption of ready-to-eat meals significantly increased urine BPA concentrations compared with canned and fresh meal consumption. No significant difference in BPS and BPF concentrations was observed between the groups. The consumption of ready-to-eat meals was associated with a significant increase in systolic blood pressure and pulse pressure and a marked decrease in diastolic blood pressure and heart rate. No significant differences were noted in blood pressure and heart rate with canned and fresh meal consumption. It can be concluded that total BPA concentration in consumed ready-to-eat meals is high. High BPA intake causes increase in urinary BPA concentrations, which may, in turn, lead to changes in some cardiovascular parameters.

Potential Nano/Microcenters of Crystal Nucleation in Reagent-Grade Purity Solvents and Their Differentiation by Fluorescent-Tagged Antiscalant

A common issue in studies on liquid-phase chemical processes is that the natural solid nanoimpurities present in reagent-grade chemicals are ignored. Little is known about these impurities’ nature, sizes, concentrations, and behavior, yet they significantly affect the efficiency of antiscalants in municipal and laboratory solutions. Recent research has focused on: (i) estimating nanoimpurity concentrations in in-house deionized water and semiconductor-grade isopropanol using “light sheet” optical ultramicroscopy, and (ii) visualizing antiscalant sorption on these impurities. Using a fluorescent-tagged antiscalant aminobis(methylenephosphonic acid) (ADMP-F), we tracked its affinity to particulate matter in deionized water and reagent-grade KCl solutions. Our study showed that the total concentration of nanoparticles with a size larger than 20 nm is about 106 units/mL in deionized water and 105 units/mL in isopropanol. Extrapolation of these values to a size ≥1 nm resulted in concentrations of 1011 and 108 units/mL. The addition of KCl or ADMP-F significantly increased foreign nanoparticle populations. ADMP-F is selectively adsorbed by only some impurities, while most antiscalant molecules remain as true solution. To our knowledge, this is the first instance of fluorescently labeled aminoalkylphosphonates being able to differentiate particulate matter traces in reagent-grade purity solutions. Therefore, the role of nanoparticles as crystallization centers should be seriously reconsidered, especially in their important application in scale inhibition.

Assessment of Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) Mass Flux and Distributions in a Lake System Using Sediment Bed Passive Flux Meters and Ceramic Dosimeters

AbstractPer‐ and polyfluoroalkyl substances (PFAS) are persistent in the environment due to their chemical stability and can spread quickly in a lake system due to mixing. Passive samplers allow for time‐weighted average concentration monitoring and the ability to detect low concentrations, which are difficult to measure with conventional grab sampling. This study demonstrates the feasibility of deploying both ceramic dosimeters and Sediment Bed Passive Flux Meters (SBPFMs) to assess time integrated PFAS concentrations and fluxes, respectively, at a historically contaminated PFAS lake near Baden‐Baden, Germany. Long‐term surface water grab samples resulted in the detection of PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFBS, PFHxS, and PFOS at a total concentration of approximately 1 μg/L. Dosimeters were deployed for 66 and 126 d, resulting in detected concentrations ranging from approximately 250 to 380 ng/L and 120 to 460 ng/L, respectively. The 66 d deployment resulted in the detection of PFPeA, PFHxA, PFHpA, and PFOA, whereas the 126 d deployment additionally detected PFBA, PFNA, PFDA, PFUnDA, PFDoDA, PFTeDA, PFBS, PFPeS, PFOS, PFNS, and PFDS. SBPFMs resulted in the detection of PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFNA, PFUnA, PFTrDA, and PFBS and the determination of a total mass discharge of 5.6 g/d into the lake. Overall, dosimeters and SBPFMs are more sensitive than grab samples at detecting PFAS at low concentrations and can be used to better understand spatial distribution of PFAS in a lake system.

Plastics and plastic-bound toxic metals in municipal solid waste compost from Sri Lanka.

This study examined plastics and toxic metals in municipal solid waste compost from various regions in Sri Lanka. Plastics were extracted using density separation, digested using wet peroxidation, and identified using Fourier Transform Infra-Red Spectroscopy in Attenuated Total Reflection mode. Compost and plastics were acid-digested to quantify total Cd, Cu, Co, Cr, Pb, and Zn concentrations and analyzed for the bioavailable fraction using 0.01M CaCl2. Notably, plastics were highly abundant in most compost samples. The main plastic types detected were polyethylene, polypropylene, and cellophane. However, the average Cd, Cu, Co, Cr, Pb, and Zn levels were 0.727, 60.78, 3.670, 25.44, 18.95, and 130.7mg/kg, respectively, which are well below the recommended levels. Zn was the most bioavailable (2.476mg/kg), and Cd was the least bioavailable (0.053mg/kg) metal associated with compost. The Contamination factor data show that there is considerable enhancement of Cd and Cu, however, Cr, Cu, Co, and Pb are at low contamination levels. Mean geo accumulation index values were 1.39, 1.07, - 1.06, - 0.84, - 0.32, and 0.08 for Cd, Cu, Co, Cr, Pb, and Zn. Therefore, the contamination level of compost samples with Cd and Cu ranges from uncontaminated to contaminated levels, whereas Co, Cr, Pb, and Zn are at uncontaminated levels. Despite no direct metal-plastic correlation, plastics in compost could harm plants, animals, and humans due to ingestion. Hence, reducing plastic and metal contamination in compost is crucial.

Remediation of Sulfides in Produced Waters of the Oil and Gas Industry Using Hydrogen Peroxide

Produced waters are often treated in open lagoons where hydrogen sulfide (H2S) can off gas, posing a risk to human health and the environment. The aim of this study was to optimize a treatment process using hydrogen peroxide (H2O2) to oxidize H2S while minimizing off gassing. Samples of produced water from West Texas and laboratory-prepared waters utilizing sodium sulfide (Na2S) or biogenic polysulfides were oxidized with H2O2 alone or in combination with copper or iron catalysts, sodium hydroxide (NaOH), or a commercial sulfide oxidizer, HydroPower Green™. Sulfur speciation was measured using Hach test kits for sulfide/sulfate/sulfite and Dräger tubes for headspace H2S. HydroPower Green™ (HPG) helped to reduce H2S in the headspace of water samples; some of this was pH related as NaOH also worked, but not as well as HPG. The dose of peroxide necessary to oxidize sulfides to sulfate is a function of the oxidation-reduction potential (Eh) of the water and total sulfide concentration as well as pH; approximately a 1–4:1 ratio of peroxide to sulfide concentration was needed to oxidize sulfidic waters of pH 7–10 with half-lives under 30 min. Both copper and iron catalysts reduce H2O2 demand and the half-life of H2S. Peracetic acid (PAA) and copper (II) sulfate pentahydrate (CuSO4, 5H2O) were explored as biocides for controlling sulfate-reducing bacteria (SRBs) that produce H2S. An AquaSnap (Hygenia) test kit was employed to monitor relative microbial activity in a wetland porewater containing H2S. Microbial regrowth occurred after a few days using the highest dose of PAA; these results showed that PAA was being used by bacteria as a carbon source even after the initial substantial reduction in the microbial activity. CuSO4, 5H2O at a dose of 1 ppm prevented microbial regrowth. The recommended treatment process from this research is determined by jar testing with H2O2, a base for pH control, a biocide, and possibly a metal catalyst or other co-oxidants in order to achieve oxidation of sulfides without H2S release or the precipitation of metal carbonates or oxides.

Phthalate Acid Esters (PAEs) in Indoor Dust from Decoration Material Stores: Occurrence, Sources, and Health Risks

Phthalate acid esters (PAEs) are one of the most widely used plasticizers globally, extensively employed in various decoration materials. However, studies on the impact of these materials on indoor environmental PAE pollution and their effects on human health are limited. In this study, forty dust samples were collected from four types of stores specializing in decoration materials (flooring, furniture boards, wall coverings, and household articles). The levels, sources, exposure doses, and potential health risks of PAEs in dust from decoration material stores were assessed. The total concentrations of Σ9PAE (the sum of nine PAEs) in dust from all decoration-material stores ranged from 46,100 ng/g to 695,000 ng/g, with a median concentration of 146,000 ng/g. DMP, DEP, DBP, and DEHP were identified as the predominant components. Among all stores, furniture board stores exhibited the highest Σ9PAE (159,000 ng/g, median value), while flooring stores exhibited the lowest (95,300 ng/g). Principal component analysis (PCA) showed that decoration materials are important sources of PAEs in the indoor environment. The estimated daily intakes of PAEs through non-dietary dust ingestion and dermal-absorption pathways among staff in various decoration-material stores were 60.0 and 0.470 ng/kg-bw/day (flooring stores), 113 and 0.780 ng/kg-bw/day (furniture board stores), 102 and 0.510 ng/kg-bw/day (wall covering stores), and 114 and 0.710 ng/kg-bw/day (household article stores). Particularly, staff in wall-covering and furniture-board stores exhibited relatively higher exposure doses of DEHP. Risk assessment indicated that although certain PAEs posed potential health risks, the exposure levels for staff in decoration material stores were within acceptable limits. However, staff in wall covering stores exhibited relatively higher risks, necessitating targeted risk-management strategies. This study provides new insights into understanding the risk associated with PAEs in indoor environments.

Distribution and transformation of potentially toxic elements in cracks under coal mining disturbance in farmland.

The ground cracks resulting from coal mining activities induce alterations in the physical and chemical characteristics of soil. However, limited knowledge exists regarding the impact of subsidence caused by coal mining on the distribution of potentially toxic elements (PTEs) fractions in farmland soil. In this study, we collected 19 soil profiles at varying depths from the soil surface and at horizontal distances of 0, 1, 2, and 5m from the vertical crack. Using BCR extraction fractionation, we determined the geochemical fractions and total concentrations of Chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb) to investigate their ecological risk, spatial fraction distribution, and main influencing factors. Results showed that the values of Cd appearing in 68.7% of the samples were higher than 40 and less than 80, presented a moderate ecological risk. Chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), and lead (Pb) were mainly bound to residual fractions (> 60%) with lower mobility and Cd was dominated by F1 (acid-soluble fractions, 50%) and F2 (reducible fractions, 29%) in surface soil (0-20cm). The geochemical fractionation revealed that the mobile fractions (F1-acid-soluble and F2-reducible) of PTEs were primarily located near the crack, influenced by available potassium. In contrast, the less mobile fractions (F3-oxidizable and F4-residual) exhibited higher concentrations at distances of 2 and 5m from the crack, except for arsenic, influenced by the presence of clay particles and available phosphorus.

Forecasting daily total pollen concentrations on a global scale.

There is evidence that global anthropogenic climate change may be impacting floral phenology and the temporal and spatial characteristics of aero-allergenic pollen. Given the extent of current and future climate uncertainty, there is a need to strengthen predictive pollen forecasts. The study aims to use CatBoost (CB) and deep learning (DL) models for predicting the daily total pollen concentration up to 14 days in advance for 23 cities, covering all five continents. The model includes the projected environmental parameters, recent concentrations (1, 2 and 4 weeks), and the past environmental explanatory variables, and their future values. The best pollen forecasts include Mexico City (R2(DL_7) ≈ .7), and Santiago (R2(DL_7) ≈ .8) for the 7th forecast day, respectively; while the weakest pollen forecasts are made for Brisbane (R2(DL_7) ≈ .4) and Seoul (R2(DL_7) ≈ .1) for the 7th forecast day. The global order of the five most important environmental variables in determining the daily total pollen concentrations is, in decreasing order: the past daily total pollen concentration, future 2 m temperature, past 2 m temperature, past soil temperature in 28-100 cm depth, and past soil temperature in 0-7 cm depth. City-related clusters of the most similar distribution of feature importance values of the environmental variables only slightly change on consecutive forecast days for Caxias do Sul, Cape Town, Brisbane, and Mexico City, while they often change for Sydney, Santiago, and Busan. This new knowledge of the ecological relationships of the most remarkable variables importance for pollen forecast models according to clusters, cities and forecast days is important for developing and improving the accuracy of airborne pollen forecasts.

Measurements of Total Aerosol Concentration in the Stratosphere: A New Balloon‐Borne Instrument and a Report on the Existing Measurement Record

AbstractThe Stratospheric Total Aerosol Counter (STAC) is a lightweight balloon‐borne instrument that utilizes condensational growth techniques to measure the total aerosol concentration. STAC is a miniaturized version of the legacy Wyoming condensation particle counter that operated from 1974 through 2020 in the middle latitudes and polar regions, with a few measurements in the tropics. Here we provide a description of the STAC instrument and the total aerosol measurement record, demonstrating that typical total aerosol profiles exhibit a peak in number mixing ratio, with values between 800 and 2,000 particles per mg of air (mg−1), just below the lapse rate tropopause (LRT). In the tropics and middle latitudes, mixing ratios decrease above the LRT likely due to coagulation and scavenging that results in a transfer of mass to the fewer but larger aerosol particles of the Junge layer. Exceptions to this occur in the spring time in the middle latitudes where a new particle layer between 20 and 25 km is frequently observed. In the poles, total aerosol profiles exhibit two distinct features: new particle formation in austral spring, and an increasing mixing ratio above 17 km likely due to the presence of meteoric smoke that has been concentrated within the polar vortex. High observed stratospheric particle mixing ratios, in excess of 2,000 mg−1, are observed in the polar new particle layer and at the top of polar profiles.

RSM and ANN-based Optimization of Ultrasound-assisted Extraction of Functional Components from Olive Fruit (cv Arbequina): Assessment of Antioxidant Attributes and GC-MS Profiling.

The current study proposes an optimized ethanolic extraction for the efficient recovery of high-value components from Pakistani olives (cv. Arbequina) using response surface methodology (RSM) and artificial neural networking (ANN). The extracts were investigated for antioxidant properties and GC-MS metabolite profiling. Four factors such as time, temperature, solvent concentration, and solute weight (g/100 mL) were utilized as independent variables for determining the response (% yield). The results obtained under optimum extraction conditions such as duration (25 min), temperature (45°C), solvent concentration (65%; ethanol: water v/v), and solute (7.50 g) indicated an extract yield of 40.96% from Arbiquina olives. The analysis of variance (ANOVA) for the RSM model showed significant p-values and a correlation coefficient (R2) of 0.9960, confirming model reliability. The multilayer perceptron architecture was used in ANN, and the results were fairly consistent with the experimental findings. Arbequina olive extract (AOE) demonstrated significant antioxidant ability in terms of total phenolics, total flavonoid concentration, and DPPH radical scavenging. The GC-MS analysis of AOE revealed the presence of several bioactives, including oleic acid (36.22%), hydroxytyrosol (3.95%), tyrosol (3.32%), β-sitosterol (2.10%), squalene (1.10%), sinapic acid (0.67%), α-tocopherol (0.66%), vanillic acid (0.56%), 3,5-di-tert-butylcatechol (0.31%), and quercetin.

Interference by vitamin B12-macrocomplexes: towards an effective detection and correct interpretation of hypo- and hypervitaminemia

Abstract Objectives The presence of macro-B12 is a cause of factual hypervitaminemia B12. Precipitation with polyethylene glycol (PEG) is a simple method of removing high-molecular-weight biomolecules. However, “free” molecule may co-precipitate. This fact imposes the need to establish new reference values for the post-precipitation result. The main aims of the study were to (Baeza I, Corchón A, Pérez JM, Remacha AF, Rocha H, Rodríguez-Portugal E, et al. Basic Aspects of vitamin B12. In: Communication Committee of the Spanish Society of Laboratory Medicine (SEQCML). Clinical significance of vitamin B12 deficiency. Beyond megaloblastic anemia; 2022. ISBN: 978-84-89975-60-6): establish post-PEG reference intervals (RIs) for total vitamin B12 (Iqtidar N, Chaudary MN. Misdiagnosed vitamin B12 deficiency a challenge to be confronted by use of modern screening markers. J Pak Med Assoc 2012;62:1223–9); compare the two bibliographic criteria for defining the presence of macro-B12 (Green R. Vitamin B12 deficiency from the perspective of a practicing hematologist. Blood 2017;129:2603–11); evaluate the joint usefulness of percentage post-PEG vitamin B12 recovery and post-PEG RIs to inform the real vitamin B12 status; and (Carmel R. Diagnosis and management of clinical and subclinical cobalamin deficiencies: why controversies persist in the age of sensitive metabolic testing. Biochimie 2013;95:1047–55), propose interpretative comments for ease of interpretation. Methods Prospective study in which 488 serum samples from “healthy” individuals were included and analyzed to determine recovery and RIs following PEG precipitation. Subsequently, a retrospective analysis was carried out in order to evaluate the joint usefulness of both definitions for a suspicion of macro-B12. A total of 297 cases were included. Results Recovery and post-PEG RIs determined on an Alinity i platform ranged from 60 to 107 % and from 118 to 506 pmol/L, respectively. McNemar’s test revealed statistically significant differences between both criteria for estimating interference. However, both methodologies showed good agreement. In 27 cases, the presence of macro-B12 coexisted with true hypervitaminemia B12. No case of coexistence of macro-B12 with vitamin B12 deficiency was detected in our series. Conclusions Laboratory reports should include total vitamin B12 concentration, recovery and post-PEG vitamin B12 concentration with their adjusted RIs to better assess the body vitamin status.

Total mercury concentrations in Tasman Sea mesopelagic fish: Exploring biotic and abiotic drivers

Understanding mercury (Hg) concentrations in mesopelagic and mid-trophic fishes is important for assessing Hg accumulation in oceanic ecosystems and higher-order predators. This study measured total Hg (THg) concentrations in the whole body of 16 abundant mesopelagic fish species sampled in two distinct sites within the Tasman Sea. Across all species, total Hg concentrations ranged from 0.02 to 0.48 μg g−1 dry weight (0.01 to 0.15 μg g−1 wet weight). Total Hg concentrations varied with vertical migration patterns, with shallower migrators exhibiting higher THg. Females typically had statistically higher THg concentrations than males. Positive correlations between THg concentration and standard length were observed for some but not all species. At the community level, THg concentrations correlated positively with estimated trophic position and foraging habitat, as inferred by stable isotope values. These findings contribute to our understanding of Hg cycling in oceanic ecosystems and the potential for biomagnification in oceanic top-order predators.

Impact of replacing protein pellets with soybean grain on nutrient utilization and the rumen and blood parameters of feedlot cattle under tropical conditions.

The aim of this study was to explore the effect of replacing protein pellets with soybean grain in high-concentrate diets with or without the addition of silage, on the intake, digestibility, and rumen and blood parameters of feedlot cattle in tropical regions. Four cannulated, crossbred steers were used, 4.5 ± 0.5 years old, with an average weight of 685.55 ± 111.78kg. The steers were distributed in a 4 × 4 Latin square, in a 2 × 2 factorial scheme (two sources of protein: protein pellets or whole soybean grain, with or without added dietary bulk). There was no effect (P ≥ 0.109) from the interaction between the source of protein and the addition of silage to the diet on dry matter (DM) and nutrient intake, or the digestibility (P ≥ 0.625) of DM or crude protein (CP). However, both factors affected (P ≤ 0.052) the intake of DM, neutral detergent fiber (NDF), and non-fiber carbohydrates (NFC), as well as the independent digestibility (P ≤ 0.099) of fat, NFC, total carbohydrates (TC), and total cholesterol concentration. There was an effect (P ≤ 0.053) from the interaction between the source of protein and the addition of silage to the diet on the digestibility of NDF and total digestible nutrients (TDN), as well as on the glycose concentration (P = 0.003). Blood parameters (i.e. protein, albumin, creatinine, triglycerides, aspartate aminotransferase (AST), and alanine aminotransferase (ALT)) were not affected (P ≥ 0.139) by the source of protein, the addition of silage, or their interaction. Lastly, including 150g/kg silage DM in a high-grain diet, and using soybean grain as a source of protein in substitution of protein pellet could be a suitable nutritional strategy to ensure adequate DM and nutrient intake and digestibility, with no detrimental effects on rumen and blood parameters of feedlot cattle in the tropics.