Variable Concentrations Research Articles

Determinants for Sugar-Induced modulation of thermodynamic stability of lysozyme

The current study focuses on the experimental evidence to describe the molecular mechanism by which the sugars modulate the thermodynamic stability of hen egg-white lysozyme (Lyz) at pH 2.3. Analysis of thermal and chemical denaturation curves of Lyz under variable concentrations of sugar (trehalose, sucrose, maltose, glucose, ribose, glycerol) at pH 2.3 depicted important results: (i) sugar increases the thermodynamic stability of Lyz, and it typically tracks the order as: trehalose > sucrose > maltose > glucose > ribose > glycerol, and (ii) sugar increases the thermodynamic stability of Lyz via preferential exclusion of sugar at the protein surface, but the repulsive enthalpic interactions of sugar with protein also add to the sugar-mediated increase in thermodynamic stability of the protein. Analysis of the sugar effect on denaturant concentration dependent denaturation free energy of Lyz at pH 2.3 revealed that the sugar counteracts the denaturant (urea, guanidinium chloride (GdnCl)) efficacy to decrease the thermodynamic stability of Lyz. Furthermore, the counteraction efficiency of sugar on denaturant impact to decrease thermodynamic stability of Lyz typically tracks the order as: trehalose > sucrose > maltose > glucose > ribose > glycerol.

Medicinal Plants Approach for Diabetes Mellitus-A Computational Model

The multidimensional metabolic syndrome that includes diabetes mellitus poses a serious threat to world health. There is an increasing interest in researching herbal remedies for their possible therapeutic advantages, even as traditional allopathic treatments continue to be widely used. This work throws light on the multiple ways of metabolism and biochemical interactions of medicinal plants in the control of glucose level, highlighting their crucial role in the process. The work clarifies several herbal extracts' efficacy and safety profiles, such as Aloe vera, Garlic, Gurmar, Bitter Melon, Neem, Tulsi, and through a thorough literature review and empirical evidence. These plants, which are abundant in bioactive substances like tannins, flavonoids, and alkaloids, show promise in treating insulin resistance, improving pancreatic function, and controlling blood sugar level. A further assessment of the rising risk associated with diabetes mellitus is discussed, and a differential equation model for diabetes mellitus is developed to minimize the complications. When using medicinal plants to treat diabetes, several factors are considered, including blood sugar level, sugar intake activity, and plasma insulin concentrations. The stability criterion for the mathematical model is examined through the system of differential equations. A representation highlighting the medicinal plants that can aid individuals with diabetes mellitus is provided. The blood sugar level, insulin generalization variable and plasma insulin concentration have all been measured at different points in time. Aloe vera, Gurmar, Garlic, Tulsi, Bitter Melon and Neem are among the medicinal plants selected for their demonstrated anti-hyperglycemic properties due to their easy availability in India. Mathematical solutions were calculated for every plant and proved to be steady.

Physio-chemical and microbial assessment of the source of drinking water and the prevailing waterborne diseases in Gwagwalada Municipal Area Council of Abuja, Nigeria

Water contamination poses a serious threat to the wellbeing of people globally. In Nigeria, there have been increasing cases of waterborne diseases owing to water contamination, thus becoming public health concerns. This study investigated the physio-chemical properties, microbial loads of borehole water samples from Gwagwalada area council of Abuja and its prevailing waterborne diseases. Borehole water samples were collected from five wards of the council area (Gwagwalada central (YZTM), University of Abuja Staff quarters (YZTMB), Dobi (SBWTM), Tunga Maje (TMCBW), and Ikwa (YZBTM) in triplicate and analyzed for physiochemical properties (temperature, conductivity, pH, turbidity, salinity, total dissolved solids (TDS), and heavy metals) and microbial contamination using standard methods. Surveillance to determine the prevalence of waterborne diseases was also carried out in the health facilities of the area council. All samples showed variable concentrations in most of the physiochemical parameters and were within the recommended thresholds except for conductivity (596.01 ± 0.00 μS/cm) and chlorine (254.18 ± 0.00 mg/l) in TMCBW sample and total dissolved solids in TMCBW (948.01 ± 14.14 mg/l) and YZTM (GC) (1871.00 ± 55.15 mg/l) water samples. E. coli, Enterobacter spp., Shigella spp., Lactobacillus spp., Pseudomonas ssp., and Proteus ssp. were bacteria isolates of the samples. Principal component analysis of interrelationship showed a strong positive relationship between some physio-chemical parameters and sampling locations. Also, there was heavy burden of gastrointestinal (waterborne) diseases. The study concludes that the borehole samples from the area were contaminated and maybe unfit for consumption. Thus, call for interventions that provide safer portable water or treat existing water sources towards achieving SDG No. 6 and to prevent outbreaks of waterborne diseases that could emanate from the consumption of unsafe water.

Snow as an Indicator of Atmospheric Transport of Anthropogenic Particles (Microplastics and Microfibers) from Urban to Arctic Regions

We report anthropogenic particles (AP) > 100μm, including microplastics and microfibers, from 70 surface snow samples collected from the urban Greater Toronto Area (GTA), remote and sparsely inhabited regions in the Yukon and Northwest Territories, and the unpopulated high Arctic. Concentrations and proportions of particles of anthropogenic origin were conservatively estimated after blank and ‘anthropogenic origin’ corrections were performed based on visual analysis and micro-Fourier transform infrared spectroscopy (µFTIR). AP were dominated by microfibers (95-100%), with variable concentrations across and within regions. Microfibers were distinguished as synthetic, regenerated semi-synthetic, anthropogenically modified cellulosic, and natural cellulosic or proteinaceous. Among microfibers with confirmed anthropogenic origin, most were polyester/PET (8-22%) and semi-synthetic rayon (1-18%), with anthropogenic cellulose comprising a small proportion (3-7%) across all regional areas. Greater diversity of coloured non-fibrous particles (fragments, films and foams) in settled regions (i.e., GTA and Carcross, Yukon) suggests direct input from local sources. Back trajectory analyses performed for days leading up to sample collection showed high frequency transport (>10%) from population centres exceeding 200km distance. Our findings of APs in snow from uninhabited areas support the hypothesis that APs, especially microfibers, undergo long-range atmospheric transport whereby snow can scavenge and deposit APs in remote northern regions.

Analysis of Volatile Organic Compound Emissions in 3D Printing: Implications for Indoor Air Quality

This study provides a comprehensive analysis of volatile organic compound (VOC) emissions in the context of 3D printing, a rapidly advancing technology that is transforming manufacturing processes. As the adoption of 3D printing grows, concerns regarding its potential impact on indoor air quality have emerged. This research addresses these concerns by investigating the risks associated with VOC emissions and proposing effective mitigation strategies. Using a robust methodology, filament and resin-based 3D printers were employed alongside VOC sampling equipment (Tenax tubes and personal pumps) to assess emissions. A detailed analysis of 49 VOCs revealed variable concentrations across different printing materials, with ethyl acetate being the dominant compound in resin printing and decanal in filament printing. While individual VOC levels were below 1% of occupational exposure limits, total VOC concentrations frequently exceeded the recommended indoor threshold of 200 µg/m3, particularly in resin-based processes. This raises concerns about the combined effects of multiple VOCs, some of which are known carcinogens. These findings underscore the need for further investigation into the cumulative health impacts of prolonged exposure to multiple VOCs. The study also emphasises the importance of accounting for both facility-specific conditions and material emissions to fully understand the environmental and health consequences of 3D printing. Preventative measures, such as enclosing 3D printers and equipping them with extraction systems, are recommended to safeguard user health.

VALIDATION OF 2HG-TARGETTED MR SPECTROSCOPY FOR IDENTIFYING IDH-MUTANT GLIOMAS

Abstract AIMS Diffuse gliomas, the most common adult primary brain tumour, are classified by their histological and molecular characteristics and genetic profile. Isocitrate dehydrogenase (IDH) mutant gliomas correlate with longer mean survival and progression-free survival time. In tumour cells, IDH mutations lead to metabolic changes and the production of oncometabolite 2-hydroxyglutarate (2HG). MR spectroscopy (MRS) can assess metabolic changes in disease states in-vivo and non-invasively. In this study, we demonstrate a validation pathway for two advanced MRS methods to be used as IDH-mutation biomarkers in clinic. METHOD Simulated, phantom, and healthy volunteer experiments were performed to optimise and validate three MRS sequences tuned for measuring 2HG. A PRESS sequence was used with TR/TE of 2500/97 ms aiming at the 2HG peaks around 2.25 ppm. An edited PRESS sequence, named MEGA-PRESS, tailored to 2HG 4.02 ppm peak was used with TR/TE of 3000/68 ms, 128 averages, and with editing pulses at 1.9 and 7.5 ppm. A long TE semi-LASER MRS sequence, with improved voxel localisation, was also used (TR/TE: 2500/110 ms). RESULTS Simulations were performed to find optimised sequence parameters and to develop basis sets for analysing the phantom and healthy volunteer acquisitions. Tumour-mimicking phantoms with variable concentrations of 2HG and cystathionine were created and validated with 800 MHz NMR spectroscopy. Phantoms were then used to assess the sensitivity and specificity of the MRS for 2HG and cystathionine. MEGA-PRESS proved Synthetic in-vivo 2HG spectra, combined from healthy volunteers and simulated or phantom-2HG spectra, were used to assess the spectral quality needed to reliably measure 2HG. CONCLUSION MEGA-PRESS proved to be the most robust MRS method and demonstrated accurate and precise measurement of phantom and synthetic 2HG with acceptable SNR. Clinical validation of the technique will need to be performed on LGG patient population, and the overall accuracy will be compared with patient IDH mutation status.

Phthalate Esters in Different Types of Cosmetic Products: A Five-Year Quality Control Survey.

Phthalate esters are commonly included in the formulations of cosmetics and related products in order to retain fragrance, enhance flexibility (i.e., by acting as plasticizers), facilitate the dissolution and dispersion of other ingredients, and improve the overall texture and sensory experience of the products. This study aimed to assess the presence and concentrations of phthalates in cosmetics by analyzing a comprehensive set of samples collected over a period of five years (2016-2020). The concentrations of nine different phthalate esters (BBP, DEHP, DNOP, DPP, DBP, DIPP, DMEP, DMP and PIPP) in 1110 cosmetics samples from France and Spain were determined by gas chromatography-mass spectrometry. The samples were included in five categories: soaps and shampoos; hand and body creams; lip gloss and lipsticks; nail polish; and facial makeup and skincare products. Some of the samples (4.86%) contained at least one phthalate at concentrations above the threshold limit (1 µg mL-1). Variable concentrations of different phthalates were determined in the 54 positive samples identified. DEHP was the most frequently detected phthalate, followed by DBP. The findings revealed different profiles according to the different categories of cosmetics and the phthalates detected in each. The results were critically compared with those obtained in various previous studies.

Modeling of Bacillus cereus evolution in pasteurized cow milk locally distributed at point of sale: a case of three companies in Tlemcen region, Algeria

Bacillus cereus is among the most hazardous bacteria that could reduce the shelf life of pasteurized milk and could threaten consumers’ health. These bacteria groups are known for their heat resistance and their ability to produce two types of toxins, diarrheic and emetic. This study aimed to enumerate the B. cereus in raw cow’s milk collected from three companies in the Tlemcen region, then modeled, based on a probabilistic approach, their evolution throughout the process, split into six steps, until the point of sale. At first, the analysis of 242 samples on MYP medium, shows a high prevalence between 92% and 98% of B. cereus with variable concentrations among the three companies. Throughout the storage of milk at refrigeration temperatures (2°C, 4°C and 5°C), no growth of B. cereus was estimated. Otherwise, the pasteurization process reduces the contamination level depending on pasteurization temperature as for company A, the mean concentration decreases from 1.53 log CFU/mL to 1.07 log CFU/mL. In this study, the distribution step at ambient temperature changes significantly the B. cereus concentration to reach a critical concentration during July and August. In conclusion, the quality of raw cow milk must be controlled before reception on the farm and the cold chain must be maintained throughout all process points until consumption.

Polybacterial Intracellular Macromolecules Shape Single-Cell Epikine Profiles in Upper Airway Mucosa.

The upper airway, particularly the nasal and oral mucosal epithelium, serves as a primary barrier for microbial interactions throughout life. Specialized niches like the anterior nares and the tooth are especially susceptible to dysbiosis and chronic inflammatory diseases. To investigate host-microbial interactions in mucosal epithelial cell types, we reanalyzed our single-cell RNA sequencing atlas of human oral mucosa, identifying polybacterial signatures (20% Gram-positive, 80% Gram-negative) within both epithelial- and stromal-resident cells. This analysis revealed unique responses of bacterial-associated epithelia when compared to two inflammatory disease states of mucosa. Single-cell RNA sequencing, in situ hybridization, and immunohistochemistry detected numerous persistent macromolecules from Gram-positive and Gram-negative bacteria within human oral keratinocytes (HOKs), including bacterial rRNA, mRNA and glycolipids. Epithelial cells with higher concentrations of 16S rRNA and glycolipids exhibited enhanced receptor-ligand signaling in vivo. HOKs with a spectrum of polybacterial intracellular macromolecular (PIM) concentrations were challenged with purified exogenous lipopolysaccharide, resulting in the synergistic upregulation of select innate (CXCL8, TNFSF15) and adaptive (CXCL17, CCL28) epikines. Notably, endogenous lipoteichoic acid, rather than lipopolysaccharide, directly correlated with epikine expression in vitro and in vivo. Application of the Drug2Cell algorithm to health and inflammatory disease data suggested altered drug efficacy predictions based on PIM detection. Our findings demonstrate that PIMs persist within mucosal epithelial cells at variable concentrations, linearly driving single-cell effector cytokine expression and influencing drug responses, underscoring the importance of understanding host-microbe interactions and the implications of PIMs on cell behavior in health and disease at single-cell resolution.

Mechanisms of Chemically Promoted Material Removal Examined for Molybdenum and Copper CMP in Weakly Alkaline Citrate-Based Slurries

Chemical mechanical planarization (CMP) of metal components is an essential step in the fabrication of integrated circuits. Metal CMP is a complex process where strategically activated (electro)chemical reactions serve to structurally weaken the surface layers of the material being processed, and the resulting overburdens are removed under low-force abrasion. Understanding the tribo-electrochemical mechanisms of this process is crucial to successfully designing the consumable materials for advanced CMP slurries that are needed for the new technology nodes. Using a model CMP system involving copper (wiring material in interconnect structures) and molybdenum (a new diffusion barrier material for copper), the present work illustrates a tribo-electroanalytical scheme for studying various mechanistic details of metal CMP. Electroanalytical probes are employed both in the absence and in the presence of surface polishing to quantify the interplay between mechanical abrasion and chemical surface modification. Weakly alkaline slurry formulations are tested with variable concentrations of silica abrasives and a complexing agent, citric acid. The results serve to examine the link between material removal and tribo-corrosion and to identify the functions of the active slurry additives in governing the rates and selectivity of material removal for CMP.

Viscoelastic dusty fluid Couette flow with heat and mass transfer across a porous oscillating plate in a rotating frame

AbstractThis research aims to enhance industrial processes and address environmental issues by studying the effects of suction and injection on the Couette flow of a viscoelastic dusty fluid over a porous oscillating plate in a rotating frame. We investigate how these factors influence fluid flow, heat, mass, and temperature transfer rates. Suction and blowing are common techniques for controlling fluid flow in conduits. The study considers the impact of the right plate's oscillation on fluid velocity along the x‐axis, as well as mass diffusion and thermal effects from the heating of the right plate. Due to the rotation, the velocities of both the fluid and dust particles exhibit complex primary and secondary behaviors. Also considered the dust particles are homogenously distributed in the base fluid. Furthermore, the variable temperature and concentration are associated with boundary conditions. We develop a mathematical model using partial differential equations (PDEs) to describe these phenomena. The governing equations are non‐dimensionalized and transformed into ordinary differential equations (ODEs) using periodic solutions and solved via the Poincare‐Lighthill perturbation method. Key engineering parameters such as the Sherwood number, Nusselt number, and skin friction are calculated. The study reveals the influence of uniform suction/injection on velocity and temperature distributions, showing that suction can significantly alter boundary layer development, even under resonance conditions. The radiation parameter, Grashof number, and second‐grade parameter cause a decrease in skin friction as their values increase. On the other hand, suction, rotation, magnetic, dusty fluid, and Reynold numbers cause a rise in skin friction.The objective of this research is to improve industrial processes and tackle environmental issues by examining the effects of suction and injection on the Couette flow of a viscoelastic dusty fluid over a porous oscillation plate in a rotating frame. The purpose of this study is to determine how suction/injection influences the Couette flow of a viscoelastic dusty fluid, as well as the heat, mass, and temperature transfer rates across a porous, oscillating plate in a rotating frame. It also takes heat transfer into account. When manipulating the flow of a fluid via a conduit, suction and blowing are common methods. As the right plate oscillates, the x‐axis becomes the primary consideration for fluid velocity. We also take into account the mass diffusion and thermal influence on the flow from the right plate's heating. As a consequence of the spin, the fluid, and dust particles have velocities that are both secondary and primary, making them complicated. Using PDEs, we may translate the aforementioned physical phenomena into a mathematical model of the relevant flow regime. The system of governing equations is non‐dimensionalized by the use of appropriate nondimensional variables. The system of PDEs is transformed into a system of ODEs with the help of assumed periodic solutions and then solved by the perturb solution with the help of Poincare‐Lighthill perturbation methods. We also calculate the Sherwood number, the Nusselt number, and the skin friction, all of which are of relevance to engineers. We also examine how changing these variables affects the velocity distributions of skin friction, viscoelastic fluid, and dust particles. We look at how uniform suction/injection affects the speed and temperature distributions. It is important to note that even in the resonance instance, suction/ injection directs the boundary layer to develop unexpectedly.

Investigation of the agricultural reuse potential of urban wastewater and other resources derived by using membrane bioreactor technology within the circular economy framework

The European Union, as delineated in Regulation (EU) 2020/741, sets forth minimum criteria for the reuse of wastewater. Directive 86/278/CEE sets the regulations for the reuse of sewage sludge in agriculture. This study aimed to investigate the treated water derived from a pilot plant situated in Granada, Spain, that utilizes membrane bioreactor technology to process real urban wastewater with the quality standards necessary for agricultural reuse. Additionally, the study evaluated the utilization potential of other resources generated during wastewater treatment, including biogas and biostabilized sludge. The pilot plant incorporated a membrane bioreactor featuring four ultrafiltration membranes operating continuously alongside a sludge treatment line operating in batch mode. The pilot plant operated during four cycles, each with distinct hydraulic retention times (6 h and 12 h) and variable mixed liquor-suspended solids concentrations (ranging from 2688 mg L−1 to 7542 mg L−1). During these cycles, the plant was doped with increasing concentrations of emerging contamination compounds (diclofenac, ibuprofen, and erythromycin) to test their effect on the resources derived from the treatment. Subsequently, a tertiary treatment involving an advanced oxidation process was applied to the different water lines, which left the wastewater treatment plant for a period of 30 min and utilized varying concentrations of oxidant. The results indicate that the effluent obtained meets the required quality standards for agricultural use. Therefore, there is potential to use this waste as a resource, which is in line with the principles of the circular economy. Furthermore, the other resources generated during the treatment process, such as the biogas produced during the digestion process and the biostabilized sludge, have the potential to be used as resources according to the circular economy indicators.

Development of over 30-years of high spatiotemporal resolution air pollution models and surfaces for California

California’s diverse geography and meteorological conditions necessitate models capturing fine-grained patterns of air pollution distribution. This study presents the development of high-resolution (100 m) daily land use regression (LUR) models spanning 1989–2021 for nitrogen dioxide (NO2), fine particulate matter (PM2.5), and ozone (O3) across California. These machine learning LUR algorithms integrated comprehensive data sources, including traffic, land use, land cover, meteorological conditions, vegetation dynamics, and satellite data. The modeling process incorporated historical air quality observations utilizing continuous regulatory, fixed site saturation, and Google Streetcar mobile monitoring data. The model performance (adjusted R2) for NO2, PM2.5, and O3 was 84 %, 65 %, and 92 %, respectively.Over the years, NO2 concentrations showed a consistent decline, attributed to regulatory efforts and reduced human activities on weekends. Traffic density and weather conditions significantly influenced NO2 levels. PM2.5 concentrations also decreased over time, influenced by aerosol optical depth (AOD), traffic density, weather, and land use patterns, such as developed open spaces and vegetation. Industrial activities and residential areas contributed to higher PM2.5 concentrations. O3 concentrations exhibited no significant annual trend, with higher levels observed on weekends and lower levels associated with traffic density due to the scavenger effect. Weather conditions and land use, such as commercial areas and water bodies, influenced O3 concentrations.To extend the prediction of daily NO2, PM2.5, and O3 to 1989, models were developed for predictors such as daily road traffic, normalized difference vegetation index (NDVI), Ozone Monitoring Instrument (OMI)–NO2, monthly AOD, and OMI-O3. These models enabled effective estimation for any period with known daily weather conditions.Longitudinal analysis revealed a consistent NO2 decline, regulatory-driven PM2.5 decreases countered by wildfire impacts, and spatially variable O3 concentrations with no long-term trend. This study enhances understanding of air pollution trends, aiding in identifying lifetime exposure for statewide populations and supporting informed policy decisions and environmental justice advocacy.

Microstructure, mechanical and tribological characterization of magnetron sputtering ZrN and ZrAlN coatings

In this research paper, mechanical and tribological characterization of novel high wear-resistant ZrN-ZrAlN coatings are presented. The varying concentrations of AlN is chosen to evaluate the influence of AlN the surface morphological, nanomechanical, and tribological properties of the composite coating. The coatings were developed on D9 steel substrates using nitrogen reactive gas radio frequency (RF) magnetron sputtering of zirconium and aluminium targets in an argon plasma. Variable power density for the aluminium target and constant power density for zirconium, was used to obtain in a systematic way, the variable concentration of AlN in the coating. Surface morphological studies were carried out to evaluate composition and crystal structure using X-ray diffraction (GIXRD), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDS). Coatings display a polycrystalline structure, but the level of crystallinity decreases with higher AlN concentration. Nanomechanical and nano scratch testing, along with tribological experimental studies were performed to comprehensively analyse performance of the developed coatings. Higher hardness of composite coating is achieved with optimal concentration of AlN in ZrN-ZrAlN coating. Adhesion strength of the coatings increased with the increase in the concentration of AlN. ZrN-ZrAlN coatings depicted low wear, however coatings containing AlN exhibits superior wear resistance.

Orange Peels as Activated Carbon Charcoal For Cu (II) Ions Elimination From Water Sources

Objectives: The goal of this work is to create inexpensive Orange Peel Activated Carbon (OPAC) for the environmentally friendly to eliminate of Cu (II) from its aqueous solution. Methods: activated carbon made by calcining orange peels at 500°C to cause them to burn. Methods: The samples were characterized using FTIR, transmission electron microscopy, and nitrogen adsorption-desorption. Cu (II) was adsorbed in a batch procedure utilizing 0.25 g of (OPAC) and 100 mL of solution with varying beginning concentrations ranging from 20–80 mg/L. The investigation focused on the effects of variables pH, temperatures, concentrations, dosages, and times on the adsorption capacity. Thermodynamic parameters were computed, adsorption kinetics were assessed using pseudo-first and pseudo-second-order were computed models, and the adsorption isotherms were fitted using the Langmuir and Freundlich models. Findings: The stretching of the hydroxyl groups is shown by peaks at 3100 and 4000 cm-1 as well as the 3300–3800 cm-1 region in the FTIR. Findings: the functionalized (OPAC). N2 adsorption isotherm revealed a hysteresis loop in the p/p0 region between 0.2 and 1. The surface area of obtained mesoporous OPAC was 0.99 nm. The maximum adsorption capacity (79.056 mg/g). Removal of Cu (II) was 99%. The adsorption process was spontaneous and less random, as indicated by the negative values of thermodynamic parameters (∆S° -14.0, ∆H°-54.76, and ∆G°-60.36 kJ.mol-1). According to the findings, orange peel has a high surface area and is highly porous, which allows it to effectively remove over 99% of harmful heavy metals from water sources. Novelty: The study proves that orange peel can be effectively used as one of the best-quality, reasonably priced, readily available, eco-friendly bio-sorbents that is also beneficial to the economy in the long run. Keywords: Orange peel, Cu (II), Adsorption, Kinetic, Thermodynamic, IFTR

Gigartina skottsbergii Setchell & N.L.Gardner (Rhodophyta) Incorporated Organic@Inorganic Hybrid Cu3(PO4)2 Nanoflowers with an Intrinsic Antioxidant and Catalytic Activities

AbstractIn this study, the extract of one of the red algae, Gigartina skottsbergii was used for synthesis of organic@inorganic hybrid nanoflower (hNFs) for the first time. hNFs were sytematically synthesized with different concentrations of algal extract (from 0.5 to 1.65 ml) and Cu2+ in different pHs (7.4 and 9) of PBS. Hierarchical synthesis of hNFs in the PBS buffer did not occur in the acidic medium (pH: 5). The morphological structures of hNFs were detailed with FE-SEM images. hNFs synthesized in morphology closest to the ideal flower structure with variable algal extract concentrations and pH were determined by FE-SEM. Organic and inorganic groups (structural components of hNFs), crystallinity of optimum synthesized hNFs were detailed by FT-IR, EDX and XRD analysis, respectively. It has been recorded that synthesized hNFs have antioxidant properties. hNFs have captured catalytic dyes with peroxidase-like activity. The ability of hNFs in destroying the dye in the presence of H2O2 has been attributed to the Fenton reaction. As a result, an easily applicable, inexpensive, one-step catalyst was synthesized using the Fenton mechanism. It is foreseen that the study data can be applied for nanotechnology field and basic sciences.

Therapeutic Drug Monitoring for Sirolimus in Children with Vascular Anomalies: What Can We Learn from a Retrospective Study.

Objectives: Sirolimus (SRL), a mammalian target of rapamycin inhibitor, has been widely used to treat patients with vascular anomalies (VAs). The objectives of this study were to summarize the routine blood SRL monitoring data for VAs children, to investigate the factors contributing to the variable blood SRL concentrations and to evaluate the efficacy and safety of SRL therapy. Methods: VAs patients with routine blood SRL monitoring from July 2017 to April 2022 at the Department of Burns and Plastic Surgery, Children's Hospital of Nanjing Medical University were retrospectively collected. Clinical data were obtained from the hospital information system. Results: In total, 67 children (35 females) were enrolled. The therapeutic drug monitoring data showed that the range of measured blood trough concentrations (Ctrough) was 3.6-46.8 ng/mL. At the initial measurements, only 33% of patients were in the target concentration range (10-15 ng/mL). But this proportion became 54% at the last measurements. The whole blood-Ctrough-to-daily dose (Ctrough/Dose) ratio was significantly associated with age and body weight (BW). The patients' laboratory results did not change significantly after SRL treatment. Although the incidence of adverse events was relatively high (44.8%), most of them were mild and tolerable. 70.3% patients had total responses to SRL, whereas 29.7% children exhibited stable disease or progressive disease. No significant differences were found in Ctrough between the total response group and non-response group. Conclusions: This retrospective study revealed a high variability in SRL blood concentrations in Chinese children with VAs. Of note, pediatric patients with older age and a higher BW had a lower Ctrough/Dose ratio. It is a concern whether the range of 10-15 ng/mL is feasible for Chinese children based only on our study. Further studies recruiting more patients are required to redefine the target reference range for children with VAs.

Experimental study of the stability of MoO<sub>2</sub>CL<sub>2</sub>° (aq) in hydrothermal solutions at 100-350 °C and saturated vapor pressure

The solubility of crystalline MoO3 in HCl solutions with variable concentration was investigated at 100, 155, 200, 250, 300, 350 °C and saturated vapour pressure. The results showed that MoO3 solubility increases with HCl concentration. Using the OptimA program, Gibbs energies of MoO2Cl2 complex have been determined. The stability constants of MoO2Cl2 are calculated according to the reaction: MoO3(c) + 2HCl(aq) → MoO2Cl2o(aq) + + H2O (l). The pK values are 1.07 0.29; 1.06 0.49; 1.74 0.71; 1.83 0.47; 1.50 0.28; 0.95 0.57 at 100, 155, 200, 250, 300, 350 °C (saturated vapour pressure).

Mobility and fractionation of rare earth elements during black shale weathering: Implications from acid rock drainage and sequential extraction study

Black shale is a type of sedimentary rocks that are enriched in rare earth elements (REEs). It is of both economic importance and environmental significance to understand REE mobility during black shale weathering. The present study approaches to this by analysing REEs in acid rock drainage (ARD) from black shale weathering system, fresh and weathered black shales, soils derived from black shales, and sequential extractants from black shales at Dongping town in Hunan province (China). Results showed that REEs had variable high concentrations in ARD as shown by total REE + Y (∑REY) concentrations from 162 to 4074 (μg/L). REEs in ARD displayed hat-shape NASC-normalized patterns with significant enrichments of middle REEs (MREE) relative to light REEs (LREE) and heavy REEs (HREE), and had significant negative Ce (Ce/Ce⁎ = 0.6) and positive Y (Y/Y⁎ = 1.5) anomalies. MREE enrichment in ARD could be evaluated using MREE/MREE⁎ values, which varied from 1.43 to 1.81 with a mean of 1.65, distinctly higher than those of whole rocks (around 1.0). 1 M HCl extraction results suggested that REEs were integratedly mobilized during shale weathering, while six-step extraction studies identified that REEs in ARD resulted from exchangeable and Fe-oxide fractions with MREE and HREE enrichment in shales respectively. MREE in exchangeable and HREE in Fe-oxide fractions were preferentially released during weathering, as illustrated by plots of MREE/MREE⁎ against HREE/LREE ratios of ARD and six-step extractants. Therefore, geochemical processes for REE mobility during black shale weathering included integrated mobilization and preferential release. Integrated REE mobilization resulted from the dissolution of REE-bearing minerals and oxidation of sulfides. Preferential REE release resulted from acid fluids produced by sulfide oxidation during weathering. Thus, a new model was proposed for interpreting geochemical processes of REE mobility during black shale weathering, and for understanding REE distribution in ARD from natural and anthropogenic systems.

Comparing seasonal heterogeneity of phytoplankton habitat and community in northern lakes with low to moderate but historically variable DOC concentrations

Comparing seasonal heterogeneity of phytoplankton habitat and community in northern lakes with low to moderate but historically variable DOC concentrations