Physicochemical Data Research Articles

Cosmetic UV filters in the environment-state of the art in EU regulations, science and possible knowledge gaps.

The aim of this work was to review the principals of environmental hazard and risk assessment (ERA) of cosmetic UV filters registered under EU REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals). Furthermore, effects as obtained from non-standardized testing methods and organisms from scientific literature were compared against the predicted no effect concentrations (PNECs) as derived based on standardized test methods for the various environmental compartments under REACH. The REACH dossiers at the ECHA webpage were screened for available information related to basic physico-chemical data (i.e. water solubility, octanol-water partitioning coefficient), PNECs and associated data (data basis, assessment factors (AFs)). Scientific literature was screened for available ecotoxicity data and the adverse effect levels were compared against the derived PNECs under REACH. Current approaches for environmental risk assessments of UV filters were evaluated for its applicability for a direct release scenario. Under REACH, PNECs were derived for all hazardous UV filters. Although, PNECs were often derived for various environmental compartments (i.e. freshwater, marine water, sediment, soil), results from literature focused on aquatic data. Effects as observed within scientific literature matches in principle with the hazardous profile of the UV filters. Effects levels both on the acute and the chronic toxicity as retrieved from the non-standardized test organisms (literature) were above the derived PNECs under REACH. Currently, ERAs performed for cosmetic UV filters under REACH are solely tonnage driven and thus do not fully capture the use in sunscreens and associated leisure activities. Existing EU REACH regulation is considered as sufficient to evaluate the environmental safety of UV filters used in sunscreens. To cover the direct release of UV filters due to various leisure activities into the aquatic freshwater and marine environment, an additional application-based ERA is considered necessary.

Unveiling novel perspectives on niche differentiation and plasticity in rhizosphere phosphorus forms of submerged macrophytes with different stoichiometric homeostasis

Stoichiometric homeostasis is the ability of organisms to maintain their element composition through various physiological mechanisms, regardless of changes in nutrient availability. Phosphorus (P) is a critical limiting element for eutrophication. Submerged macrophytes with different stoichiometric homeostasis regulated sediment P pollution by nutrient resorption, but whether and how P homeostasis and resorption in submerged macrophytes changed under variable plant community structure was unclear. Increasing evidence suggests that rhizosphere microbes drive niche overlap and differentiation for different P forms to constitute submerged macrophyte community structure. However, a greater understanding of how this occurs is required. This study examined the process underlying the metabolism of different rhizosphere P forms of submerged macrophytes under different cultivation patterns by analyzing physicochemical data, basic plant traits, microbial communities, and transcriptomics. The results indicate that alkaline phosphatase serves as a key factor in revealing the existence of a link between plant traits (path coefficient = 0.335, p < 0.05) and interactions with rhizosphere microbial communities (average path coefficient = 0.362, p < 0.05). Moreover, this study demonstrates that microbial communities further influence the niche plasticity of P by mediating plant root P metabolism genes (path coefficient = 0.354, p < 0.05) and rhizosphere microbial phosphorus storage (average path coefficient = 0.605, p < 0.01). This research not only contributes to a deeper comprehension of stoichiometric homeostasis and nutrient dynamics but also provides valuable insights into potential strategies for managing and restoring submerged macrophyte-dominated ecosystems in the face of changing nutrient conditions.

ANALYSIS OF VISCOSITY CORRELATIONS APPLICABILITY FOR OILS OF THE REPUBLIC OF BASHKORTOSTAN

Decisions quality of infrastructure development also depends on the reliability of multiphase flow modeling results in oil and gas production systems. Different specialized bundled software and Informational System RN-KIN are used for the modeling of multiphase systems to solve the assigned tasks for Republic Bashkortostan’s oil fields.&#x0D; The modeling practice assumes the handling of large amount of initial data: geometrical properties of pipe systems, terrain elevation, technological modes of pumping, conditions of heat exchange with the environment, transport properties of oil fluid. Information about network construction and terrain elevation can be obtained from the projects and the acts of implementation of these projects, the conditions of pumping are available from operation-dispatch information, but verification of viscosity properties of oil fluids causes difficulties and requires additional laboratory tests. At the same time on&#x0D; oil fields of Republic Bashkortostan a lot of experimental physicochemical properties data of oils belonging to different oil reservoirs has been accumulated, which requires systematization and generalization of available experimental data.&#x0D; The article describes the difficulties in modeling of viscosity of oil fluids taking into account the characteristics of physicochemical properties of oils of Republic Bashkortostan’s oil fields. The necessity of systematization of existing retrospective laboratory tests and selection of viscosity correlations is indicated. &#x0D; The authors of the article for the first time analyzed and selected correlations of viscosity of oil and water-oil emulsions for Republic Bashkortostan’s oil fields, which will allow to increase accuracy and efficiency of hydraulic calculations on which basis the decisions about development of infrastructure of fields are made.

Cashew peduncle pulp in the production of Berliner Weisse craft beer: Sensory and physicochemical aspects

Among the extant beer types, Berliner Weisse is mainly characterized by its blend of barley and wheat malts, Saccharomyces cerevisiae for alcoholic fermentation, and Lactobacillus spp. for lactic fermentation. In this study, three formulations of Berliner Weisse were developed with various concentrations of barley, wheat malts, and hops. No variations were made in the concentrations of S. cerevisiae, Lacticaseibacillus casei, or cashew pulp. A L. casei-free formulation was used as a control. Physicochemical and sensory parameters were evaluated to characterize the formulations. The physicochemical data allowed for differentiation of the beverages in all evaluated parameters, except for the percentages of titratable acidity and diacetyl. From a sensory perspective, panelists classified the beer as acidic or fruity. The cashew peduncle pulp was proven to be a viable and attractive alternative for the production of Berliner Weisse-style beer with national characteristics and versatility in physicochemical and sensory parameters.

Physicochemical and Sensory Evaluation Data to Drive the Development of a Green Chili Pepper Hot Sauce from Unexploited Raw Materials.

The present study shows the set of analyses conducted during the development of a hot chili pepper sauce to valorize green peppers usually discarded in the Espelette region (France). A traditional production process was used as the inspiration for product development, and two different fermentation processes were assessed and characterized by measuring pH, sugar content, instrumental color, volatile composition, and conducting sensory (discriminant test) and microbiological analyses (total plate count). Significant differences were observed among pepper mash samples with respect to their physicochemical characteristics, but the products were considered similar from a sensory standpoint. Both sensory and physicochemical tests suggested that the ingredients added to make the sauces were determinant and had a higher impact on the organoleptic profile of the final product than the fermentation process. Finally, a Napping® test was conducted to determine the attributes that could differentiate the product from the hot sauces found in the current market. The results of the present research allowed the optimization of the elaboration process of the new product, saving time and ingredient costs. The procedures shown in the study could be used as an example of a new product development process in which physicochemical and sensory data are collected and used for decision making.

Solubility data and solubility parameters of barnidipine in different pure solvents

Introduction: Solubility studies and obtaining physicochemical data on drugs in pure solvents belonging to different chemical classes are key to developing new drug formulations. In this work, Hansen partial solubility parameters (HSP) were calculated to assess the miscibility and intermolecular interactions of barnidipine in seventeen pure solvents. The comparison of the results obtained with the theoretical values ​​calculated according to the structure of barnidipine, were valuable to analyse the influence of the solute-solute, solute-solvent relationships of the additive contribution groups, on the chemical and physical properties of this molecule with the solvents of different polarity tested, to provide relevant information highly useful in the pharmaceutical industry. Method: Equilibrium barnidipine solubilities in mono-solvents was determined using the classical shake-flask method, followed by UV-spectrophotometric analysis at 298.15 K. The partial solubility parameters were calculated by applying theoretical group contribution methods, proposed by Hoftyzer-Van Krevelen and Fedors. The KAT-LSER model was used to investigate the effect of solvent based on the concept of linear solvation energy relationships. The mole fraction was obtained from the densities of the solutions. Solid-phase analyses were made by calorimetry differential scanning. Results: The modification introduced in the extended Hansen method, that is, the use of lnX2 as the dependent variable, provided excellent results. The highest solubility values have been found in polar solvents. It is observed that solvent-solvent and solute-solvent intermolecular interactions through hydrogen bonds and van der Waals forces, significantly influence drug solubility. Conclusions: The affinity between barnidipine and each one of the selected solvent was evaluated by using HSP. Results showed that HSP could be well used to analyse drug solubility in particular solvents. Barnidipine is easier to dissolve in solvents with shorter carbon chains and higher polarity.

Design, synthesis, and biological evaluation of indole-2-carboxamides as SARS CoV-2 main protease inhibitors

Using a repurposing approach, a series of previously reported antiproliferative indole-based carboxamides (9–23) were reassessed for their anti-SARS-CoV-2 viral activity as main protease (SARS-CoV-2 Mpro) inhibitors. The structure of the indole-based carboxamides was validated by comparing the acquired data to previously report physicochemical and NMR spectroscopy data. The anti-SARS-CoV-2 activity of the synthesised compounds was tested in Vero-E6 cells using SARS-CoV-2 (NRC-03-nhCoV) virus. MTT cytotoxicity assay results demonstrated that compounds 9–23 had CC50 (50% cytotoxicity concentration) values ranging from 325.60 to 578.50 μM and safety indices ranging from 21.40 to 99.60. Most of the compounds examined significantly inhibited NRC-03-nhCoV virus replication, with IC50 values ranging from 3.60 μM to 15.20 μM, with compounds 11, 19, and 20 having the most potent anti-SARS-COV-2 activity. The inhibitory effect of compounds 11, 13, 14, 19 and 20 against SARS-CoV-2 Mpro was investigated. The findings of this test were consistent with the anti-SARS CoV-2 experiment. Inflammatory cytokine tests revealed that compounds 11, 19 and 20 have antiviral effectiveness against SARS-CoV-2 and can reduce hyper inflammation. Finally, docking studies of the novel compounds in the SARS CoV-2-Mpro active site revealed a good match.

Pharmacognostical and phytochemical studies on leaves of Tagetes erecta Linn.

Background: Tagetes erecta Linn. (Asteraceae) is a well-known plant for its antihypertensive, antioxidant, antidiabetic, aphrodisiac, and hepatoprotective properties. To investigate the pharmacognostic, physicochemical, and phytochemical determinations of this plant's leaves. Materials and Methods: The macroscopic characteristics of the leaves, such as size, colour, surface characteristics, texture, fracture characteristics, and odour, were studied pharmacognostically. The cellular characteristics of the drug were studied using a microscope on both the intact leaves and the powdered drug. According to WHO guidelines, extractive values, loss on drying (LOD), total ash, water-soluble and acid-insoluble ash, and moisture content of Tagetes erecta leaves powder were determined. For the various phytoconstituents, preliminary phytochemical screening and qualitative chemical examination studies have been conducted. Results: TLC analysis revealed the presence of alkaloids, glycosides, flavonoids, steroids, saponins, and tannins. Microscopic examination revealed the presence of xylem vessels, vascular bundles, and phloem fibres. Conclusion: To authenticate, standardise, and avoid adulteration in the raw material, pharmacognostical and preliminary phytochemical screening of Tagetes erecta leaves will be beneficial. The diagnostic microscopic characteristics and physicochemical data will aid in the creation of a monograph. The chromatographic fingerprinting profile can be used to standardise Tagetes erecta leaf extracts and formulations.

Chemical constituents from stems and leaves of Cratoxylum cochinchinense and their inhibitory effects on proliferation of synoviocytes in vitro

The chemical constituents from the stems and leaves of Cratoxylum cochinchinense were isolated and purified using silica gel, ODS gel, and Sephadex LH-20 gel column chromatography, as well as preparative HPLC. The chemical structures of all isolated compounds were identified on the basis of their physicochemical properties, spectroscopic analyses, and the comparison of their physicochemical and spectroscopic data with the reported data in literature. As a result, 21 compounds were isolated from the 90% ethanol extract of the stems and leaves of C. cochinchinense, which were identified as cratocochine(1), 1-hydroxy-3,7-dimethoxyxanthone(2), 1-hydroxy-5,6,7-trimethoxyxanthone(3), ferrxanthone(4), 3,6-dihydroxy-1,5-dimethoxyxanthone(5), 3,6-dihydroxy-1,7-dimethoxyxanthone(6), 1,2,5-trihydroxy-6,8-dimethoxyxanthone(7), securixanthone G(8), gentisein(9), 3,7-dihydroxy-1-methoxyxanthone(10), pancixanthone B(11), garcimangosxanthone A(12), pruniflorone L(13), 9-hydroxy alabaxanthone(14), cochinchinone A(15), luteolin(16), 3,5'-dimethoxy-4',7-epoxy-8,3'-neolignane-5,9,9'-triol(17), N-benzyl-9-oxo-10E,12E-octadecadienamide(18), 15-hydroxy-7,13E-labdadiene(19), stigmasta-4,22-dien-3-one(20), and stigmast-5-en-3β-ol(21). Among these isolates, compound 1 was a new xanthone, compounds 2-5, 7, 8, 12, and 16-21 were isolated from the Cratoxylum plant for the first time, and compounds 11 and 13 were obtained from C. cochinchinense for the first time. Furthermore, all isolated compounds 1-21 were appraised for their anti-rheumatoid arthritis activities by MTS method through measuring their anti-proliferative effect on synoviocytes in vitro. As a result, xanthones 1-15 displayed notable anti-rheumatoid arthritis activities, which showed inhibitory effects on the proliferation of MH7A synoviocytes with the IC_(50) values ranging from(8.98±0.12) to(228.68±0.32) μmol·L~(-1).

Statistics and 3D Modelling on Soil Analysis by Using Unmanned Aircraft Systems and Laboratory Data for a Low-Cost Precision Agriculture Approach

The aim of this work was to elaborate a new methodology that can allow for the identification of the topsoil homogeneous area (tSHA) distribution along land parcels, supporting farmers in keeping low-cost, sustainable, and light logistic management of precision agriculture (PA) practices. This paper shows the assessment of tSHA variability over two production units (PUs), considering radiometric response (optical camera), physicochemical (texture, pH, electrical conductivity), and statistical and geostatistical data analysis. By using unmanned aircraft systems (UASs) and laboratory analysis, our results revealed that the integration between UAS-RGB and physicochemical data can improve the estimation accuracy of tSHA distribution. Firstly, the UAS-RGB dataset was used to isolate bare soil from the vegetative radiometric contribution. Secondly, starting from statistical approaches (correlation matrices), the highest correlation with UAS-RGB and physicochemical data was stated. Thirdly, by using a geostatistical approach (ordinary cokriging), the map representing the tSHA variability was finally obtained.

Mt. Apo Biotic Index (MABI): a macroinvertebrate-based multimetric index for assessing stream biotic integrity of wadeable streams within a geothermal production field in Mindanao, Philippines.

Monitoring the ecological integrity of streams is a challenge, especially in the tropics, which experience high rates of degradation. Multimetric scoring systems have been widely used in other countries in evaluating current stream conditions; however, it has never been done in the Philippines. This study focuses on the development of a benthic macroinvertebrate-based multimetric index for the overall assessment of streams in Mt. Apo, Mindanao, Philippines. The index was used to develop existing physicochemical and biological data obtained during 2010 to 2015 surveys from 15 monitoring sites within the Mt. Apo Geothermal Project (MAGP). Metrics related to benthic macroinvertebrate abundance, richness, composition, functional habit groups, functional feeding groups, and pollution tolerance were screened for their range, temporal stability, sensitivity, discrimination efficiency (DE), redundancy, and responsiveness to anthropogenic impacts. The resulting multimetric index, the Mt. Apo Biotic Index (MABI), is computed as the sum of the individual metric scores after metric transformation using the discrete scoring method DRQ1 (D = discrete, R = reference, Q1 = 25th percentile) of the six core metrics: (1) number of Coleoptera individuals (abundance), (2) number of taxa (richness); (3) [%] Coleoptera taxa (composition), (4) number of sprawler individuals (functional habit group), (5) [%] collector-filterer taxa (functional feeding group), and (6) the Biological Monitoring Working Party Thai version (BMWP-Thai; pollution tolerance). MABI scores were classified into five condition ratings of stream biotic integrity: very poor (6 to 10), poor (11 to 15), fair (16 to 20), good (21 to 25), and excellent (26 to 30). The study demonstrated that the resulting pilot index may provide useful information that will benefit policymakers and resource managers in formulating more comprehensive stream management approaches and conservation plans for priority sites in the region.

Factors controlling the variation in physicochemical parameters of springs in Melamchi area, Nepal

Understanding the factors controlling the spatial and seasonal variation of physicochemical parameters of groundwater are important for quick water quality assessment and for a better planning of the water quality management strategies. This study evaluated spring’s five physicochemical data (pH, EC, TDS, DO and temperature) for 75 springs in two seasons (pre and post monsoon). The aim of the research presented in this paper is to assess physicochemical parameters of spring water, understand their seasonal and spatial variation and the factors controlling the variation. Physicochemical parameters were correlated with each other to understand the processes and an attempt has been made to understand groundwater processes studying the physicochemical parameters. Groundwater is slightly acidic to slightly alkaline with pH ranging from 5.5 to 7.5 and is weakly to very weakly mineralized with EC range of 21.6–234.0 μS/cm in pre-monsoon and 10.5–189.8 μS/cm in post-monsoon. TDS ranged between 5.3–116.9 mg/l and 10.8–94.9 mg/l, DO between 3.1–9.4 mg/l and 2.4–7.3 mg/l and groundwater temperature between 18.4–27.9°C and 19.2–27.4°C in pre-monsoon and post monsoon season respectively. TDS and EC are noted to be higher in pre-monsoon whereas pH, DO and temperature are comparatively higher in post-monsoon. The south-east region of the study area shows minimum groundwater temperature. Minimum concentration of EC and TDS were observed in south-east and north-west part of the study area with values increasing towards the river valley. Groundwater temperature shows inverse relation with elevation, pH and DO while correlated with EC and TDS of groundwater in the region. The measured parameters were seasonally and spatially variable. The results indicate difference for measured physicochemical parameters mainly caused due to results generated by cumulative interactions of monsoonal rain, atmospheric temperature, rock-groundwater interaction, residence time of groundwater and seasonal influences. The change in parameters with respect to elevation and relation between different parameters shows shallow aquifer-related groundwater processes.

Investigating flavor sensory properties of Zhenjiang aromatic vinegar and factors impacting perception using quantitative descriptive analysis and temporal dominance of sensations

AbstractThe aim of this study was to make a sensory scientific and chemical characterization of flavor profiles of Zhenjiang aromatic vinegar (ZAV) from different grades, and to investigate their potential correlation for evaluating the effects of chemical components on sensory perception. The quantitative descriptive analysis (QDA) was combined with temporal dominance of sensations (TDS) to assess the sensory properties of different grades of ZAV. The grades of ZAV were best differentiated by pungent (p &lt; .001), almond (p &lt; .001), burnt (p &lt; .001), sour (p &lt; .001), bitter (p &lt; .001), and salty perception (p &lt; .001). TDS showed ZAV of five grades differed in the combination of dominant sensory attributes. Both QDA and TDS differentiated the ZAV samples of different grades. Multiple factor analysis (MFA) of QDA, aroma, and physicochemical data showed these data set were well correlated, which contributed to the identification the chemical drivers of sensory attributes.Practical ApplicationsZhenjiang aromatic vinegar (ZAV) is a highly appreciated product all over the world due to its unique and pleasant flavor sensory properties. The combined use of QDA and TDS permitted the identification and quantitative description of flavor profiles for ZAV from different grades while providing additional information during the consumption of ZAV, which has proved to be more beneficial than each just on its own. In addition, the key flavor substances that influence the sensory attributes were found out by analyzing the variables correlations and product spaces though MFA, thus it is help to strengthen the flavor quality control in the ZAV products. Taken overall, this work provides a reference for the measurement of flavor profiles of ZAV related products and evaluation the internal chemical components affecting sensory attributes.

Synthesis, characterization of 4-{[(E)-{2-hydroxy-3-[(Z)-1,3-thiazol-2-yldiazeneyl]napthalen-1-yl}methylidene]amino}benzoic acid and its transition metal complexes; biopharmaceutical activities and electrochemical detection of ciplactin

A Schiff base derivative, 4-{[(E)-{2‑hydroxy-3-[(Z)-1,3-thiazol-2-yldiazeneyl]napthalen-1-yl}methylidene]amino}benzoic acid (ENB) and some of its transition metal complexes were synthesised. The structure of the ENB and its complexes were characterised by NMR, FT-IR, mass spectra, TGA, UV–visible, PXRD and ESR techniques. Physico-chemical data suggest an octahedral geometry nature. Molecular docking for all the synthesised compounds has been performed to predict the binding affinity. The [Ni(ENB)2] exhibited excellent binding score of -284.32 kcal/mol In vitro cytotoxicity activities on lungs cell line A459 exhibited significant IC50values and the results indicated that [Co(ENB)2] is a stronger antioxidant agent. Electrochemical detection of bioactive drug ciplactin using a modified electrode, MWCNT-[Co(ENB)2]/GCE showed an excellent sensing ability with a long linear range 10-90 µmol/L, sensitivity 0.4765 µAµM−1cm−2 and its LOD is 3.333 µmol/L in PBS pH 7. Further, the modified electrodehas more stability and less leaching property in the detection system.

Time series analysis of groundwater quality at selected sites of Purba and Paschim Burdwan, West Bengal, India.

The Water Quality Index (WQI) is used to monitor the health and usability of a water body. In this study, we aimed to construct time series prediction models using groundwater WQI (GW-WQI) at four sites: IISCO-Asansol, Durgapur Town, Burdwan University, and Burdwan Station. While statistical spatio-temporal analysis has been reported earlier, no time series analysis of the data or predictive modelling has been done. Pre-monsoon and post-monsoon physico-chemical data from 2010 to 2022 were obtained from the West Bengal Pollution Control Board website to calculate the GW-WQI. Prediction modelling was performed using R 4.1.3 software. Best fit forecast models were selected to predict future trends of GW-WQI with 80% of the data. Subsequently, the models were validated using R-squared, root mean square error (RMSE), mean absolute error (MAE), maximum absolute percentage error (MAPE), and Thiel's U for the model using 20% of the data. Our results show that GW-WQI was good in pre-monsoon but unfit for drinking in post-monsoon in IISCO-Asansol, Durgapur Town, Burdwan University, and Burdwan Station. Arsenic, fluoride, and mercury were the major contaminants resulting in poor GW-WQI. Seasonal ARIMA was the best model for Burdwan University and IISCO-Asansol, ETSfor Durgapur Station, and BaggedARIMA for Burdwan Station. The forecast model for Durgapur and Burdwan Station predicted a sharp increase until 2027 but was fluctuating for IISCO-Asansol and Burdwan University. Thus, GW-WQI is a major problem in the industrial belt of West Bengal that is likely to remain high or worsen in the future.

Gasoline discrimination using infrared spectroscopy and virtual samples based on measurement uncertainty

In a previous work, we proposed a methodology for pair-wise discrimination of gasoline samples by creating virtual samples based on physicochemical assays or distillation curves. Satisfactory results were achieved, although specialist and specific apparatus (not commonly available at police laboratories) were required. The present study goes a step further and for the first time investigates the possibility of infrared (IR) spectroscopy to enable a virtual samples-based methodology for comparison of gasoline samples in pairs. IR spectroscopy feasibility for in situ applications is attractive for forensic investigations. The performances of one handheld NIR device and one dual-range (FT-NIR and FT-IR) benchtop spectrometer were evaluated. The estimation of uncertainty in infrared spectral measurement (needed to generate virtual samples) is barely discussed in literature. So far, there are no literature reports describing quantification and comparison of measurement uncertainties for the spectral acquisitions evaluated here, especially regarding their use for generating virtual samples. A stepwise procedure to quantify uncertainties associated with IR spectral acquisition, at each wavenumber, is described. This method can be useful for understanding both the sources of variability in IR measurements and the system under investigation. Uncertainty estimation was based on experimental data and considered intermediate precision, repeatability and variations in sample temperature as sources of variability. Virtual samples were employed in a discrimination approach using SIMCA models. Results for portable NIR, FT-NIR and FT-IR data sets showed complete discrimination for 96.3%, 93.4% and 93.7% of the 1431 pairs of gasoline samples evaluated, respectively. These results were comparable and similar to those obtained for the physicochemical properties data set (95.7%), although slightly inferior to the result obtained for distillation curves (99.2%). Using IR non-destructive methods in this case could enable faster investigations and simpler analysis, especially for the low-cost handheld spectrometer. In a screening approach, atmospheric distillation assays can be employed only if infrared techniques are not capable of distinguishing the samples subject to comparison. In this work, a pair of samples was considered to be completely discriminated only when a null false positive error (FPR) was achieved, although a more flexible criterium may be acceptable in practice. Finally, the methodology could be extended to other applications where sample comparison is important.

Water Quality Classification and Machine Learning Model for Predicting Water Quality Status—A Study on Loa River Located in an Extremely Arid Environment: Atacama Desert

Water is the most important resource for human, animal, and vegetal life. Recently, the use of artificial intelligence techniques, such as Random Forest, has been combined with other techniques, such as models of logical–mathematical reasoning, to generate predictive water quality models. In this study, a rule-based inference technique to generate water quality labels is described, using historical physicochemical parameter data on seven water monitoring stations in Loa River, collected by the Chilean Ministry of the Environment. Next, a predictive model of water quality status was created, using Random Forest, physicochemical parameters, and expert knowledge. The validation of Random Forest results is described using three quality indicators from the machine learning model: accuracy (acc), precision (p), and recall (r). This paper describes dataset preparation, the refinement of the threshold values used for the physicochemical parameters most significant in the class, and the predictive model labeling water quality. The models obtained yielded the following mean values: acc = 0.897, p = 89.73, and r = 0.928. The ML model reported here is novel since no previous studies of this kind predict the water quality of Loa River, located in an extremely arid zone. This study also helps to create specific knowledge to predict freshwater quality.

In vitro study on antitumor activity of aurantiamide acetate extracted from Polygonum capitatum

Aurantiamide acetate is a dipeptide derivative with antibacterial, antiviral, anti-inflammatory and analgesic activities. However, its antitumor activity has not been documented. This study aimed to prepare aurantiamide acetate from Polygonum capitatum and investigate its antitumor activity in vitro. The petroleum ether extract fraction of 80% ethanol extract from P. capitatum was separated by silica gel column chromatography. Aurantiamide acetate was obtained and identified by physicochemical properties, MS and NMR spectral data. The inhibitory effect of different doses of this compound on the proliferation of human umbilical vein endothelial cells (HUVECs), human gastric cancer BGC-823 cells, lung cancer A549 cells and colorectal cancer Caco-2 cells was detected by CCK-8 method. Morphological changes of BGC-823 cells were observed under the inverted microscope. The effect of aurantiamide acetate on BGC-823 apoptosis and cycle was detected by flow cytometry. The expression of Bax and caspase-3 in BGC-823 cells was detected by Western blotting. Aurantiamide acetate inhibited BGC-823, A549 and Caco-2 cell proliferation at the concentrations from 25 μmol/L to 100 μmol/L, but had no inhibitory effect on HUVECs at the concentrations from 12.5 μmol/L to 100 μmol/L. The inhibitory effect of Aurantiamide acetate was most pronounced on BGC-823 cell proliferation at IC50 of 56.73 μmol/L, most probably by increasing the protein expression of caspase-3 and Bax in BGC-823 cells, and arresting cell cycle in G2/M phase. This is the first time that we isolated aurantiamide acetate from P. capitatum with a purity of 98.21%, and found that Aurantiamide acetate could in inhibit the proliferation of various cancer cell types in vitro. This finding may provide a new resource for developing anti-tumor drugs in future.

Variation in Larval Fish Assemblage Dynamics Associated with Harmful Algal Blooms in a Temperate Estuary, South Africa

Eutrophication and concomitant harmful algal blooms (HABs) are on the rise globally and pose a threat to larval stages of fishes that rely on estuarine nursery habitats for growth and survival. The anthropogenically altered low inflow estuary (LIE), Sundays Estuary, South Africa, supports persistent and predictable HABs. This study investigated the effects of HABs on the environmental conditions and larval fish assemblage of this warm temperate nursery area. Sampling took place during the austral spring of 2016 and 2018 at three sites in the mesohaline zone where both larval fish abundance and HABs are known to reach maxima. Physico-chemical and phytoplankton data were collected during the day and night, while larval fishes were sampled after nightfall. Physico-chemical parameters and larval fish assemblages were compared by water column (surface and bottom) and sites within the mesohaline zone, years, and HAB intensity (hypereutrophic ≥ 2781 H. akashiwo cells•mL−1; standard ≥ 205 H. akashiwo cells•mL−1; none < 205 H. akashiwo cells•mL−1). A longer period of consecutive hypereutrophic bloom conditions was recorded during 2018 compared to 2016. Dissolved oxygen concentration was notably higher during hypereutrophic blooms (χ2 = 23.759, df = 2, P < 0.001) and reached a maximum of approximately 21 mg•L−1 during the day and 13 mg•L−1 at night. Density and similarity of estuarine resident larval assemblages were negatively correlated to supersaturated dissolved oxygen concentrations. Greater mean densities of estuarine resident larvae were recorded during hypereutrophic blooms compared to standard blooms and bloom absence and diversity was lower during 2018 when hypereutrophic bloom conditions were more persistent. These changes may have major implications for successful early development of fishes that rely on the Sundays Estuary and similar LIEs as a nursery.

Physiologically based pharmacokinetic modeling to assess the drug-drug interactions of anaprazole with clarithromycin and amoxicillin in patients undergoing eradication therapy of H. pylori infection

ObjectiveThis study aimed to assess the pharmacokinetic (PK) interactions of anaprazole, clarithromycin, and amoxicillin using physiologically based pharmacokinetic (PBPK) models. MethodsThe PBPK models for anaprazole, clarithromycin, and amoxicillin were constructed using the GastroPlus™ software (Version 9.7) based on the physicochemical data and PK parameters obtained from literature, then were optimized and validated in healthy subjects to predict the plasma concentration-time profiles of these three drugs and assess the predictive performance of each model. According to the analysis of the properties of each drug, the developed and validated models were applied to evaluate potential drug-drug interactions (DDIs) of anaprazole, clarithromycin, and amoxicillin. ResultsThe developed PBPK models properly described the pharmacokinetics of anaprazole, clarithromycin, and amoxicillin well, and all predicted PK parameters (Cmax,ss, AUC0-τ,ss) ratios were within 2.0-fold of the observed values. Furthermore, the application of these models to predict the anaprazole-clarithromycin and anaprazole-amoxicillin DDIs demonstrates their good performance, with the predicted DDI Cmax,ss ratios and DDI AUC0-τ,ss ratios within 1.25-fold of the observed values, and all predicted DDI Cmax,ss, and AUC0-τ,ss ratios within 2.0-fold. The simulated results show no need to adjust the dosage when co-administered with anaprazole in patients undergoing eradication therapy of H. pylori infection since the dose remained in the therapeutic range. ConclusionThe whole-body PBPK models of anaprazole, clarithromycin, and amoxicillin were built and qualified, which can predict DDIs that are mediated by gastric pH change and inhibition of metabolic enzymes, providing a mechanistic understanding of the DDIs observed in the clinic of clarithromycin, amoxicillin with anaprazole.