Water Profiles Research Articles

Investigating ultra-high dose rate water radiolysis using the Geant4-DNA toolkit and a Geant4 model of the Oriatron eRT6 electron linac

Ultra-high dose rate FLASH radiotherapy, a promising cancer treatment approach, offers the potential to reduce healthy tissue damage during radiotherapy. As the mechanisms underlying this process remain unknown, several hypotheses have been proposed, including the altered production of radio-induced species under ultra-high dose rate (UHDR) conditions. This study explores realistic irradiation scenarios with various dose-per-pulse and investigates the role of pulse temporal structure. Using the Geant4 toolkit and its Geant4-DNA extension, we modeled the Oriatron eRT6 linac, a FLASH-validated electron beam, and conducted simulations covering four distinct dose-per-pulse scenarios – 0.17 Gy, 1 Gy, 5 Gy, and 10 Gy – all featuring a 1.8 µs pulse duration. Results show close agreement between simulated and experimental dose profiles in water, validating the eRT6 model for Geant4-DNA simulations. We observed important changes in the temporal evolution of certain species, such as the earlier fall in hydroxyl radicals (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{ \\bullet } \ ext{O}\ ext{H}$$\\end{document}) and reduced production and lifetime of superoxide (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ ext{O}}_{2}^{{\\bullet\\:}-}$$\\end{document}) with higher dose-per-pulse levels. The pulse temporal structure did not influence the long-term evolution of species. Our findings encourage further investigation into different irradiation types, such as multi-pulse configurations, and emphasize the need to add components in water to account for relevant cellular processes.

Combining low- and high-frequency microwave radiometer measurements from the MOSAiC expedition for enhanced water vapour products

Abstract. In the central Arctic, high-quality water vapour observations are sparse due to the low density of meteorological stations and uncertainties in satellite remote sensing. Different reanalyses also disagree on the amount of water vapour in the central Arctic. The Multidisciplinary drifting Observatory for the Study of the Arctic Climate (MOSAiC) expedition provides comprehensive observations that are suitable for evaluating satellite products and reanalyses. Radiosonde observations provide high-quality water vapour estimates with a high vertical but a low temporal resolution. Observations from the microwave radiometers (MWRs) on board the research vessel Polarstern complement these observations through high temporal resolution. In this study, we demonstrate the high accuracy of the combination of the two MWRs HATPRO (Humidity and Temperature Profiler) and MiRAC-P (Microwave Radiometer for Arctic Clouds – Passive). For this purpose, we developed new retrievals of integrated water vapour (IWV) and profiles of specific humidity and temperature using a neural network approach, including observations from both HATPRO and MiRAC-P to utilize their different water vapour sensitivity. The retrievals were trained with the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis version 5 (ERA5) and synthetic MWR observations simulated with the Passive and Active Microwave radiative TRAnsfer tool (PAMTRA). We applied the retrievals to synthetic and real observations and evaluated them with ERA5 and radiosondes launched during MOSAiC, respectively. To assess the benefit of the combination of HATPRO and MiRAC-P compared to single MWR retrievals, we compared the errors with respect to MOSAiC radiosondes and computed the vertical information content of the specific humidity profiles. The root mean squared error (RMSE) of IWV was reduced by up to 15 %. Specific humidity biases and RMSE were reduced by up to 75 % and 50 %, respectively. The vertical information content of specific humidity could be increased from 1.7 to 2.4 degrees of freedom. We also computed relative humidity from the retrieved temperature and specific humidity profiles and found that RMSE was reduced from 45 % to 15 %. Finally, we show a case study demonstrating the enhanced humidity profiling capabilities compared to the standard HATPRO-based retrievals. The vertical resolution of the retrieved specific humidity profiles is still low compared to radiosondes, but the case study revealed the potential to resolve major humidity inversions. To what degree the MWR combination detects humidity inversions, also compared to satellites and reanalyses, will be part of future work.

Defining and Mitigating Flow Instabilities in Open Channels Subjected to Hydropower Operation: Formulations and Experiments

A thorough literature review was conducted on the effects of free surface oscillation in open channels, highlighting the risks of the occurrence of positive and negative surge waves that can lead to overtopping. Experimental analyses were developed to focus on the instability of the flow due to constrictions, gate blockages, and the start-up and shutdown of hydropower plants. A forebay at the downstream end of a tunnel or canal provides the right conditions for the penstock inlet and regulates the temporary demand of the turbines. In tests with a flow of 60 to 100 m3/h, the effects of a gradually and rapidly varying flow in the free surface profile were analyzed. The specific energy and total momentum are used in the mathematical characterization of the boundaries along the free surface water profile. A sudden turbine stoppage or a sudden gate or valve closure can lead to hydraulic drilling and overtopping of the infrastructure wall. At the same time, a PID controller, if programmed appropriately, can reduce flooding by 20–40%. Flooding is limited to 0.8 m from an initial amplitude of 2 m, with a dissipation wave time of between 25 and 5 s, depending on the flow conditions and the parameters of the PID characteristics.

Hydrogeochemical Insights into the Sustainable Prospects of Groundwater Resources in an Alpine Irrigation Area on Tibetan Plateau

The Tibetan Plateau is the “Asia Water Tower” and is pivotal for Asia and the whole world. Groundwater is essential for sustainable development in its alpine regions, yet its chemical quality increasingly limits its usability. The present research examines the hydrochemical characteristics and origins of phreatic groundwater in alpine irrigation areas. The study probes the chemical signatures, quality, and regulatory mechanisms of phreatic groundwater in a representative alpine irrigation area of the Tibetan Plateau. The findings indicate that the phreatic groundwater maintains a slightly alkaline and fresh status, with pH values ranging from 7.07 to 8.06 and Total Dissolved Solids (TDS) between 300.25 and 638.38 mg/L. The hydrochemical composition of phreatic groundwater is mainly HCO3-Ca type, with a minority of HCO3-Na·Ca types, closely mirroring the profile of river water. Nitrogen contaminants, including NO3−, NO2−, and NH4+, exhibit considerable concentration fluctuations within the phreatic aquifer. Approximately 9.09% of the sampled groundwaters exceed the NO2− threshold of 0.02 mg/L, and 28.57% surpass the NH4+ limit of 0.2 mg/L for potable water standards. All sampled groundwaters are below the permissible limit of NO3− (50 mg/L). Phreatic groundwater exhibits relatively good potability, as assessed by the entropy-weighted water quality index (EWQI), with 95.24% of groundwaters having an EWQI value below 100. However, the potential health risks associated with elevated NO3− levels, rather than NO2− and NH4+, merit attention when such water is consumed by minors at certain sporadic sampling locations. Phreatic groundwater does not present sodium hazards or soil permeability damage, yet salinity hazards require attention. The hydrochemical makeup of phreatic groundwater is primarily dictated by rock–water interactions, such as silicate weathering and cation exchange reactions, with occasional influences from the dissolution of evaporites and carbonates, as well as reverse cation-exchange processes. While agricultural activities have not caused a notable rise in salinity, they are the main contributors to nitrogen pollution in the study area’s phreatic groundwater. Agricultural-derived nitrogen pollutants require vigilant monitoring to avert extensive deterioration of groundwater quality and to ensure the sustainable management of groundwater resources in alpine areas.

Gadopiclenol: A q = 2 Gadolinium-Based MRI Contrast Agent Combining High Stability and Efficacy

Objectives Gadopiclenol is a q = 2 pyclen gadolinium-based contrast agent (GBCA) recently approved by the Food and Drug Administration, European Medicines Agency, and other European countries. The aim of this report is to demonstrate its stability in multiple stressed in vitro conditions and in vivo, in rat kidney, while maintaining its higher relaxivity compared with conventional GBCAs on the market. Materials and Methods Both gadopiclenol and its chemical precursor Pi828-Gd were characterized and compared with q = 1 gadolinium (Gd) complexes. The number of water molecules coordinated to the Gd (the hydration number, q) was determined by luminescence. 17O NMR (Nuclear Magnetic Resonance) measurements gave access to the water residence time τM. These parameters were used for the fitting of the nuclear magnetic relaxation dispersion profiles in water. Proton relaxivities of the complexes were determined in different media at 60 MHz (1.4 T), at different pH and temperature. The kinetic inertness was investigated in human serum, acidic media, under zinc competition in the presence of phosphate, and under ligand competition. The in vivo stability was evaluated in rat kidneys 12 months after repeated injections. Results The presence of 2 inner-sphere water molecules per Gd complex was confirmed for both pyclen derivatives. The high relaxivity of the complexes in water is maintained under physiological conditions, even under stressed conditions (ionic media, extreme pH, and temperature), which guarantees their efficiency in a large range of in vivo situations. Gd release from the q = 2 complexes was investigated in different potentially destabilizing conditions. Either no Gd release or a slower one than with “q = 1” stable macrocyclic GBCA (acidic conditions) was observed. Their kinetic inertness was demonstrated in physiological conditions, and the Gd release was below the lower limit of quantification of 0.1 μM after 12 days at 37°C in human serum. It was also demonstrated that gadopiclenol is stable in vivo in rat kidney 12 months after repeated injections. Conclusions Thanks to its optimized structural design, gadopiclenol is a highly stable and effective macrocyclic q = 2 GBCA.

Dynamics of flavonoid metabolites in coconut water based on metabolomics perspective.

Coconut meat and coconut water have garnered significant attention for their richness in healthful flavonoids. However, the dynamics of flavonoid metabolites in coconut water during different developmental stages remain poorly understood. This study employed the metabolomics approach using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the changes in flavonoid metabolite profiles in coconut water from two varieties, 'Wenye No.5'(W5) and Hainan local coconut (CK), across six developmental stages. The results showed that a total of 123 flavonoid metabolites including chalcones, dihydroflavonoids, dihydroflavonols, flavonoids, flavonols, flavonoid carboglycosides, and flavanols were identified in the coconut water as compared to the control. The total flavonoid content in both types of coconut water exhibited a decreasing trend with developmental progression, but the total flavonoid content in CK was significantly higher than that in W5. The number of flavonoid metabolites that differed significantly between the W5 and CK groups at different developmental stages were 74, 74, 60, 92, 40 and 54, respectively. KEGG pathway analysis revealed 38 differential metabolites involved in key pathways for flavonoid biosynthesis and secondary metabolite biosynthesis. This study provides new insights into the dynamics of flavonoid metabolites in coconut water and highlights the potential for selecting and breeding high-quality coconuts with enhanced flavonoid content. The findings have implications for the development of coconut-based products with improved nutritional and functional properties.

Iron redox shuttling and uptake by silicate minerals on the Namibian mud belt

Anoxic marine sediments represent an important source of bioavailable iron (Fe) to the ocean. The highest sedimentary Fe fluxes are observed in open-marine oxygen minimum zones where anoxic bottom waters are in contact with ferruginous surface sediments. Here, sedimentary Fe release, transport and re-deposition (i.e., Fe shuttling) may generate a lateral pattern of sedimentary Fe enrichment and depletion, which can be used to trace redox-related Fe mobility in the paleo-record. However, depending on the balance between terrigenous and authigenic (i.e., shuttle-related) Fe flux, the stability of bottom water redox conditions as well as post-depositional processes of mineral alteration, the sedimentary fingerprint of an Fe redox shuttle may be obscured and difficult to identify.We investigated sedimentary Fe cycling along two transects across the Namibian mud belt with variable terrigenous sedimentation (23°S < 25°S) and during two seasons with opposing bottom water redox conditions (oxic in austral winter versus anoxic to sulfidic in austral summer). On both transects, substantial benthic Fe fluxes up to −50 µmol m−2 d−1 were inferred based on pore water profiles. The magnitude of these fluxes is comparable to those reported for other open-marine oxygen minimum zones. On the transect at 23°S, Fe source areas with ferruginous surface sediments were clearly separated from Fe sink areas with highly sulfidic surface sediments. Therefore, Fe redox shuttling was reflected by a lateral pattern of reactive Fe depletion and enrichment relative to the terrigenous background sedimentation. By contrast, on the transect at 25°S, benthic Fe fluxes were temporally and spatially more variable and surface sediments were ferruginous or only weakly sulfidic. Therefore, sedimentary Fe depletion and enrichment was less pronounced at 25°S. In the Fe sink area at 23°S, hydrogen sulfide was present at the sediment surface during both sampling campaigns and solid phase data suggest that Fe sulfide minerals represented the main burial phase of reactive Fe. By contrast, at 25°S excess Fe was associated with potassium (K) rather than reduced sulfur. While a differing sediment provenance cannot be ruled out entirely, combined evidence from pore water silica profiles, K to Fe stoichiometric relationships and electron microprobe images suggest that laterally derived excess Fe was incorporated into pre-existing and/or authigenic clay minerals during early diagenesis. Iron uptake by clay minerals may be supported by frequent redox oscillations and sediment mixing preventing preservation of Fe sulfide minerals and promoting Fe and K fixation in clay minerals. The burial fluxes of excess Fe associated with sulfide minerals at 23°S and silicate minerals at 25°S were similar. Our findings thus underscore that neoformation or alteration of silicate minerals can be important processes within the low-temperature marine Fe cycle.

In-depth analysis of natural organic matter fractions in drinking water treatment performance: Fate and role of humic substances in trihalomethanes formation potential

In this study we investigate the compositional changes in dissolved organic matter (DOM) fractions across diverse water sources and treatment processes in three Drinking Water Treatment Plants (DWTPs). High-Performance Size Exclusion Chromatography coupled with Diode Array Detection and Organic Carbon Detection (HPSEC-DAD-OCD) was employed to characterize DOM fractions, offering insights into treatment optimization. We examine bulk water parameters, DOM distributions, and the efficiency of treatment trains in reducing DOM fractions. Results reveal distinct DOM composition profiles in river-sourced versus reservoir-sourced waters, with implications for treatment processes. Coagulation, Granular Activated Carbon (GAC) adsorption, Electrodialysis Reversal (EDR), and Ion Exchange (IEX) were evaluated for their efficacy in removing DOM fractions. The analysis highlights the effectiveness of coagulation in reducing high molecular weight (MW) fractions, while GAC filtration targets lower MW fractions. EDR shows significant removal of anions and aromatics, while IEX demonstrates high removal efficiencies for removing humic substances (HS) fractions. Spectroscopic analysis further elucidates changes HS sub-fractions and their role in disinfection by-products (DBP) formation. To quantitatively assess the relationship between HS sub-fractions and trihalomethane formation potentials (THMFP), Pearson correlation analysis were conducted, unveiling robust associations between HS sub-fractions and THM-FP that can be predicted by surrogate parameters such as A254.

Integrating short- and full-length 16S rRNA gene sequencing to elucidate microbiome profiles in Pacific white shrimp (Litopenaeus vannamei) ponds.

Despite their immense economic value as a key aquaculture species, the production of Pacific white shrimp (Litopenaeus vannamei) faces significant challenges from intensive farming practices and disease outbreaks. Routine microbial profiling for disease surveillance could be a promising approach to anticipate and control disease outbreaks. To achieve this, accuracy in microbial profiling in shrimp ponds is crucial for enabling targeted action and prevention. Extensive documentation emphasizes that, beyond biological factors (related to the host, diet, or health status during the rearing period), technical elements, including sequencing techniques significantly influence bacterial community profiling. This study investigated the influence of short- and long-read sequencing of 16S rRNA genes on the microbial profiles in shrimp intestines, water, and sediments. The origin of the samples (intestine or environmental) in shrimp culture ponds primarily drove the observed differences in core microbial species. The ecological niches accounted for 56% of bacterial community variations in culture ponds. Both sequencing approaches showed consistent results in identifying higher-rank taxa and assessing alpha and beta diversity. However, at the species level, full-length 16S rRNA gene sequences provided better resolution than V3-V4 sequences. For routine microbial profiling in shrimp culture ponds, our study suggests that short-read sequences were sufficient for determining overall bacterial community.IMPORTANCEThis interdisciplinary study investigated the influence of sequencing techniques on bacterial communities profiling within Pacific white shrimp (Litopenaeus vannamei) ponds. By integrating aquaculture, microbiology, and environmental science, we revealed the role of ecological niches and factors like salinity and pH on microbiota diversity and composition in shrimp intestines, pond water, and sediment. Additionally, we compared the taxonomic resolution using partial versus full-length 16S rRNA gene sequences, highlighting the value of longer amplicons for precise identification of key taxa. These findings provide novel insights into microbial dynamics underlying environmental effects in shrimp aquaculture. Comprehensive characterization of the pond microbiome could lead to management strategies that promote shrimp health and productivity. Furthermore, the potential of a multi-omics approach for integrating complementary data streams to elucidate environment-microbiome-host interactions was highlighted.

Two-Step Wetting of Nanoporous Carbons: Small-Angle Scattering Analysis of Capillary Rise.

Numerous applications of nanoporous materials require their pores to be filled with liquids. In spite of its huge technological importance, the conditions for the wetting of nanometer-sized pores and its phenomenology are still poorly understood. We report on capillary rise experiments with water in carbon xerogels, with synchrotron small-angle scattering used to follow the process in situ at the nanometer scale. The data reveal a two-step wetting process whereby water permeates first into molecular-sized micropores, which is followed by the imbibition of larger mesopores. A Cassie-Baxter analysis shows that the presence of water in the micropores is central, as it turns the mesopores from being hydrophobic to hydrophilic. Based on the so-calculated contact angles, the mesopore wetting kinetics are found to be quantitatively described by a classical Washburn model. Modeling of the experimental water profile ahead of the Washburn front reveals strong surface barriers opposing water transfer from the mesopores to the micropores.

Controlled release formulations of organophosphorus pesticides based on ecofriendly novel and conventional matrices for agro-environmental sustainability

Controlled release formulations (CRFs) of the organophosphorus pesticides diazinon and dichlorvos were prepared from a novel cow dung ash (CDA) matrix and the more conventional starch (STA) matrix. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the CRFs. FTIR and XRD spectral data provide evidence for pesticide-matrix interactions fundamental to observed matrix surface binding and pesticide release behaviour in water and soil environments. Properties evaluation of the CRFs reveal similar magnitudes of loading capacity and encapsulation efficiency of CDA- and STA-based CRFs of both pesticides, while the order CDA > STA prevails in matrix porosity and swelling ability. Technical grade (TG) and the CRF-encapsulated pesticides exhibit “burst” release profiles in water; pesticide quantities released at similar lengths of time follow the order TG >> STA-CRF > CDA-CRF, thus revealing the capacity of the CRFs to constrain the active ingredients from free mobility, with CDA-CRF being the more slightly efficacious. The Korsmeyer-Peppas equation reasonably models pesticide release from both CRFs into water, giving n values consistent with both water diffusion into the matrix and matrix relaxation as kinetically important in both matrices. Soil column experiments demonstrate the potential of the CFRs to mitigate ground water pollution. Overall, the results show that CDA- and STA-based CRFs of both pesticides have roughly the same potency for pesticide controlled release and ground water pollution mitigation. Deployment of these CFRs can contribute to the drive for agro-environmental sustainability, while the use of CDA, a waste material, as a matrix in controlled pesticide delivery would resonate with sustainable bioresource utilization.

Cyto- and genotoxicity evaluation of water samples collected from two rivers in the Kosovo.

River water in Kosovo is exposed to various discharges from industrial and agricultural activities as well as to urban wastewater. Rivers Sitnica and Drenica are among the most affected ones and water samples drawn from these rivers show the presence of various toxic substances. Genotoxic effects are seen in fish living in these rivers indicating a cytotoxic and mutagenic potential of the river water. Aiming at substantiating these observations, we assessed cyto- and genotoxic effects of water samples collected at different locations from Drenica and Sitnica river. Samples drawn from Lake Badovc served for comparison. To address seasonal effects, samples were collected at different seasons/time points during the period summer 2016 - spring 2018. The water samples were analyzed employing primary rat hepatocytes as reliable in vitro cell model for the assessment of cytotoxic effects (mitotic arrest and cell death) and DNA damage/genotoxicity (micronucleus assay, Comet assay). The results do not account for significant effects associated with specific locations but demonstrate seasonal differences of the genotoxic potential of the water samples collected along both rivers, which are accompanied by a limited cytotoxic potential. Our data provide substantial support to earlier observations and strongly warrant the need for continuous chemical as well as biological monitoring of the river water in Kosovo, focusing on an improved toxicant profiling of the river water and investigations addressing the observed seasonal variations.

Comparison of Physicochemical Properties, Antioxidants, and Aroma Profiles of Water- and Sodium-Hydroxide-Treated Natural Cocoa Powder.

Cocoa powder alkalization is an essential process in chocolate manufacturing, and traditionally, this process involves the use of alkaline agents, such as sodium hydroxide (NaOH), potassium hydroxide (KOH), and potassium carbonate (K2CO3). However, these methods involve harsh chemicals and energy-intensive procedures, raising significant environmental concerns. Water (H2O) has emerged as a promising alternative due to its safety, minimally harmful byproducts, and accessibility. Green chemistry principles have gained importance across industries, especially in food production, where sustainable practices are highly valued. This study aimed to develop a greener process by investigating the alkalization potential of H2O and comparing the results with those of NaOH. The particle size distribution, pH, color, antioxidant capacity, phenolic composition, and aroma profile of cocoa powders treated with H2O and NaOH were evaluated. The alkalization temperature significantly affected the color of the cocoa powders, and the alkali solution ratio influenced the L* values of H2O-treated powders. In industrial and commercial specifications, an ΔE value below 3 is considered standard for color measurements. Both H2O-treated and NaOH-treated natural cocoa powders had ΔE values exceeding 3 compared to the untreated powder, indicating that H2O treatment darkens the color in a similar way to that of traditional methods. While NaOH produced a darker color, process optimization allowed both H2O and NaOH treatments to achieve similar color attributes (ΔE < 3). Significant differences were observed in the antioxidant capacity and total phenolic content (TPC) between the H2O-treated and NaOH-treated cocoa powders. H2O treatment positively impacted the antioxidative properties of the cocoa powder. The antioxidant capacity, measured by the DPPH and CUPRAC methods, was significantly higher in H2O-treated samples (295.5-317.7 TEAC mg/100 g and 835-1542 TEAC mg/100 g, respectively) compared to NaOH-treated samples (256.6-306.2 TEAC mg/100 g and 171-849 TEAC mg/100 g, respectively). Additionally, the TPC of H2O-treated cocoa powder [281.3-321.6 gallic acid equivalent (GAE) mg/100 g] was significantly higher than that of NaOH-treated powder (100.0-298.6 GAE mg/100 g). The significant differences in the phenolic profiles suggested that the alkalization process affects individual phenolic compounds differently. Moreover, H2O-treated cocoa powders had significantly higher trimethylpyrazine/tetramethylpyrazine (TrMP/TMP) ratios than those of NaOH-treated samples, indicating notable differences in aroma profiles. This study suggests that H2O can replace NaOH in the alkalization process of the cocoa industry, particularly for lightly treated alkalized cocoa powders that maintain high antioxidant activity and TrMP/TMP ratios. This offers a more environmentally friendly, easily manageable, and sustainable process for cocoa powder alkalization.

The vehicle of administration, feed or water, and prandial state influence the oral bioavailability of amoxicillin in piglets.

Feed and water components may interact with drugs and affect their dissolution and bioavailability. The impact of the vehicle of administration (feed and water) and the prandial condition of weaner piglets on amoxicillin´s oral bioavailability was evaluated. First, amoxicillin's in vitro dissolution and stability in purified, soft, and hard water, as well as release kinetics from feed in simulated gastric and intestinal media were assessed. Then, pharmacokinetic parameters and bioavailability were determined in fasted and fed pigs using soft water, hard water, or feed as vehicles of administration following a balanced incomplete block design. Amoxicillin showed similar dissolution profiles in soft and hard water, distinct from the dissolution profile obtained with purified water. Complete dissolution was only achieved in purified water, and merely reached 50% in soft or hard water. Once dissolved, antibiotic concentrations decreased by around 20% after 24h in all solutions. Korsmeyer-Peppas model best described amoxicillin release from feed in simulated gastric and intestinal media. Feed considerably reduced antibiotic dissolution in both simulated media. In vivo, amoxicillin exhibited significantly higher bioavailability when delivered via water to fasted than to fed animals, while in-feed administration yielded the lowest values. All treatments showed a similar rate of drug absorption. In conclusion, we demonstrated that water and feed components, as well as feed present in gastrointestinal tract of piglets decrease amoxicillin´s oral bioavailability. Therefore, the use of oral amoxicillin as a broad-spectrum antibiotic to treat systemic infections in pigs should be thoroughly revised.

What defines dry skin? Correlating a range of skin hydration parameters with InVivo Confocal Raman Spectroscopy.

While there are a wide range of approaches for the assessment of skin hydration, it is not always clear how data from them relate to one another or to the skin itself. With the development of invivo Confocal Raman Spectroscopy (ICRS), it has become possible to measure water concentration as a function of protein/depth within the stratum corneum (SC). This article reports a comparison between electrical skin hydration measures/visual/optical grading and water concentration profiles measured using ICRS, to better understand the relationship between these approaches. SC hydration of lower-leg skin with varying degrees of dryness was assessed using visual grading (live and from digital images), Corneometer®, Visioscan and ICRS. In addition, a custom fingerprint sensor was used to image surface capacitance (as a surrogate of SC hydration), and SC barrier function was assessed using evaporimetry (to measure trans-epidermal water loss; TEWL). Significant correlations were observed between a number of different skin grading/measurement approaches and ICRS data. ICRS hydration profiles also revealed a region near the SC surface with a relatively flat water profile in dry skin subjects. The advent of quantitative invivo analytical techniques such as ICRS, which can be used in a clinical setting, has enabled greater insight into more conventional approaches for assessing skin dryness. While traditional skin grading and biophysical methods for measuring skin hydration have varying degrees of correlation with one another, they also provide comparatively unique information about different regions within the SC. This should enable a more informed approach to product development in the future.

Molecular Hydrogen for Outpatients with COVID-19 (Hydro-COVID): A Phase 3 Randomised, Triple-Blinded, Pragmatic, Placebo-Controlled, Multicentre Trial.

Background. Due to its antioxidant, anti-inflammatory, anti-apoptosis, and anti-fatigue properties, molecular hydrogen (H2) is potentially a novel therapeutic nutrient for patients with coronavirus acute disease 2019 (COVID-19). We determined the efficacy and safety profile of hydrogen-rich water (HRW) to reduce the risk of COVID-19 progression. Methods: We also conducted a phase 3, triple-blind, randomised, placebo-controlled trial to evaluate treatment with HRW initiated within 5 days after the onset of signs or symptoms in primary care patients with mild-to-moderate, laboratory-confirmed COVID-19. Participants were randomised to receive HRW or placebo twice daily for 21 days. The incidence of clinical worsening and adverse events were the primary endpoints. Results: A total of 675 participants were followed up to day 30. HRW was not superior to placebo in preventing clinical worsening at day 14: in H2 group, 46.1% in the H2 group, 43.5% in the placebo group, hazard ratio 1.09, 90% confidence interval [0.90-1.31]. One death was reported at day 30 in the H2 group and two in the placebo group at day 30. Adverse events were reported in 91 (27%) and 89 (26.2%) participants, respectively. Conclusions: HRW taken twice daily from the onset of COVID-19 symptoms for 21 days did not reduce clinical worsening.

Development of polysaccharide bioplastic: Analysis of thermo-mechanical properties and different environmental implications

Despite the distinct benefits of plastics, the environmental impacts stemming from their production and accumulation in the environment have become a global concern. Therefore, the development of new technologies that mitigate these impacts is of notable importance. The present study aimed to evaluate the physicochemical properties of starch-xylan-based bioplastic, and to discuss the viability of this material in terms of applications and ecological impacts. Holocellulose, xylan, and α-cellulose were extracted from waste biomass and combined with starch for bioplastic production. Solubility in food simulants (3% acetic acid, and 90% ethanol) was performed for xylan and starch-based bioplastics. Bioplastic was evaluated to grow Aspergillus versicollor for xylanase production. The bioplastic was evaluated as a photoprotector with yeast exposed to UVC light-covered by the bioplastic for 2 h. Bioplastic disintegration was evaluated in different soil moistures and the disintegration on the surface of the compost. Liquid washes from soils exposed to bioplastic biodegradation were tested for Lactuca sativa seed germination/inhibition. Water from a local lake was exposed to bioplastic and microbial cell density modification was verified. Images of the surface of the bioplastics were obtained by scanning electron microscopy, and characterized by thermogravimetric and dynamic-mechanical analysis. The xylan addition in bioplastic led to a material with a 40–50% decreased ultraviolet light transmittance. An increase in xylan concentration reduced solubility in lipid food simulant solutions, with no fatty solubilization with 25% of xylan. It suggests potential applications in photoprotective and packaging contexts. The thermal degradation temperature of the pure starch bioplastic was 324 °C, and the addition of 10% (287 °C), 15% (286 °C), and 25% (296 °C) xylan (w/w) indicated a reduction in thermal resistance, possibly due to suboptimal interaction between polymer chains. The decrease in crystallinity in the compositions 10/90% (Xc = 20%), 15/85% xylan/starch (Xc = 21%) compared to 25/75% xylan/starch (Xc = 11%) also underscored the complexity of polymer interactions within the bioplastic matrix. Tensile strength of pure starch was 1.21 MPa, while the composition of 15/85% xylan/starch exhibited improved strength 2.99 MPa. Further investigation into the interaction between starch and xylan is warranted. Concerning the disintegration of the 25/75% xylan/starch formulation in the soil, the humidity of the soil matrix played a significant role. The disintegration occurred over 5 days and 16 days in compost (55% humidity) and soil (32.6% humidity), respectively. The results of phytotoxicity (Lactuca sativa seeds) and changes in the physicochemical and biological profile of water (smell, turbidity, phosphorus and nitrogen levels, pH, and bacterial and phytoplankton density/richness), in response to exposure to bioplastics, highlight the necessity of developing this biologically-based and biodegradable technology in concerns about potential environmental impacts. Furthermore, the present study introduces the approach of bioplastic waste recycling using enzyme production biotechnology. In line with the legitimacy of bioplastics as important materials for addressing the challenges posed by their non-biodegradable synthetic counterparts, the presented results broaden the discourse on the feasibility of this biologically based material, contributing to the development of a sustainable society.

Monte Carlo simulations of microdosimetry and radiolytic species production at long time post proton irradiation using GATE and Geant4-DNA.

Radiobiological effectiveness of radiation in cancer treatment can be studied at different scales (molecular till organ scale) and different time post irradiation. The production of free radicals and reactive oxygen species during water radiolysis is particularly relevant to understand the fundamental mechanisms playing a role in observed biological outcomes. The development and validation of Monte Carlo tools integrating the simulation of physical, physico-chemical and chemical stages after radiation is very important to maintain with experiments. Therefore, in this study, we propose to validate a new Geant4-DNA chemistry module through the simulation of water radiolysis and Fricke dosimetry experiments on a proton preclinical beam line. In this study, we used the GATE Monte Carlo simulation platform (version 9.3) to simulate a 67.5 MeV proton beam produced with the ARRONAX isochronous cyclotron (IBA Cyclone 70XP) at conventional dose rate (0.2Gy/s) to simulate the irradiation of ultra-pure liquid water samples and Fricke dosimeter. We compared the depth dose profile with measurements performed with a plane parallel Advanced PTW 34045 Markus ionization chamber. Then, a new Geant4-DNA chemistry application proposed from Geant4 version 11.2 has been used to assess the evolution of , , , , , , and reactive species along time until 1-h post-irradiation. In particular, the effect of oxygen and pH has been investigated through comparisons with experimental measurements of radiolytic yields for and Fe3+. GATE simulations reproduced, within 4%, the depth dose profile in liquid water. With Geant4-DNA, we were able to reproduce experimental radiolytic yields 1-h post-irradiation in aerated and deaerated conditions, showing the impact of small changes in oxygen concentrations on species evolution along time. For the Fricke dosimeter, simulated G(Fe3+) is 15.97±0.2 molecules/100eV which is 11% higher than the measured value (14.4±04 molecules/100 eV). These results aim to be consolidated by new comparisons involving other radiolytic species, such as or to further study the mechanisms underlying the FLASH effect observed at ultra-high dose rates (UHDR).

Pathogenic bacteria and their antibiotic resistance profile in irrigation water in farms from Mexico

ABSTRACT The presence of antibiotic-resistant bacteria in the agro-environment is a growing international concern. In Mexico, few studies thus far have assessed the quality of water irrigation through the isolation of bacteria pathogens and the identification of antibiotic-resistant genes. Irrigation water samples obtained from rivers, wells, and ponds in different regions of Mexico were analyzed for the presence and antibiotic resistance of pathotypes of Escherichia coli, Salmonella spp., and Enterococcus spp. using selective agars and polymerase chain reaction. Two Enterococcus faecalis, one typical enteropathogenic (EPEC), and one atypical EPEC pathotypes were isolated from river water samples; two atypical EPEC and one enterotoxigenic pathotypes were isolated from pond water samples. There were no targeted pathogens detected in well water samples. All isolates were resistant to at least three antibiotics, with vancomycin being the most common; however, all isolates were sensitive to trimethoprim and ciprofloxacin. The presence of pathotypes of EPEC and ETEC and E. faecalis in water samples used for crop irrigation are a potential risk to public health because of their pathogenicity and antibiotic resistance.

Light enhances the production of conidia and influences their hydrophobicity in Tolypocladium inflatum

Insect fungal pathogens such as Beauveria bassiana, Metarhizium robertsii, and Tolypocladium inflatum have been used as insect biocontrol agents. Their infection mechanism involves non-specific adhesion to the host cuticle, which is controlled by hydrophobins, small proteins that form an amphipathic monolayer with rodlet morphology on diverse fungal structures. Light is an abiotic factor that may influence a wide range of cellular processes, including conidiogenesis, stress tolerance, and metabolite biosynthesis. Although its effects have been studied in many fungi, little is known about the effects of light on the hydrophobic properties of conidia. The aim of this work was to investigate the influence of visible light on the conidial hydrophobicity of three entomopathogenic fungal species. For this, conidia of B. bassiana, M. robertsii, and T. inflatum were grown either under light or in the dark, drop profiles of water and diiodomethane on conidial surfaces were analyzed, and conidial hydrophobicity was estimated from contact angle measurements. Moreover, conidial production was determined, and their genome was screened with sequences for hydrophobins. Conidia of B. bassiana and M. robertsii are more hydrophobic than conidia of T. inflatum. The light modified the surface tension of T. inflatum; therefore, conidia of T. inflatum became hydrophilic. However, light did not affect the conidial hydrophobicity of B. bassiana and M. robertsii. In addition, light modified the conidial production of B. bassiana and T. inflatum cultures, but it had no effect on the conidial production of M. robertsii. The T. inflatum genome contains two predicted proteins whose sequence is akin to that of proven class II hydrophobins from other ascomycetes. Presumably, these proteins are responsible for the conidial hydrophobicity properties in this fungus. Our study helps elucidate how light affects the conidial hydrophobicity of entomopathogenic fungi.