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Sensors (Basel, Switzerland) Aug 2016Remotely sensed data can reinforce the abilities of water resources researchers and decision makers to monitor waterbodies more effectively. Remote sensing techniques... (Review)
Review
Remotely sensed data can reinforce the abilities of water resources researchers and decision makers to monitor waterbodies more effectively. Remote sensing techniques have been widely used to measure the qualitative parameters of waterbodies (i.e., suspended sediments, colored dissolved organic matter (CDOM), chlorophyll-a, and pollutants). A large number of different sensors on board various satellites and other platforms, such as airplanes, are currently used to measure the amount of radiation at different wavelengths reflected from the water's surface. In this review paper, various properties (spectral, spatial and temporal, etc.) of the more commonly employed spaceborne and airborne sensors are tabulated to be used as a sensor selection guide. Furthermore, this paper investigates the commonly used approaches and sensors employed in evaluating and quantifying the eleven water quality parameters. The parameters include: chlorophyll-a (chl-a), colored dissolved organic matters (CDOM), Secchi disk depth (SDD), turbidity, total suspended sediments (TSS), water temperature (WT), total phosphorus (TP), sea surface salinity (SSS), dissolved oxygen (DO), biochemical oxygen demand (BOD) and chemical oxygen demand (COD).
Topics: Environmental Monitoring; Lakes; Remote Sensing Technology; Water; Water Pollutants, Chemical; Water Quality
PubMed: 27537896
DOI: 10.3390/s16081298 -
PloS One 2022Solutions with high pH values are sometimes thought to contain net negative charge because of an excess of OH- groups, while solutions with low pH values are thought...
Solutions with high pH values are sometimes thought to contain net negative charge because of an excess of OH- groups, while solutions with low pH values are thought opposite. To follow up on these speculations, we used a simple electrochemical cell to study three types of solution: electrolyzed waters with differing pH values; acids and bases with different pH values; and various salt solutions. When electrolyzed waters of various pH values were tested against water of pH 7, we found that acidic waters were indeed positively charged, while basic waters were negatively charged. We found much the same when standard acids and bases were compared to reference solutions: acidic solutions were positively charged while basic solutions were negatively charged. Various salts, including NaCl, KCl, Na2SO4, and K2SO4, were also tested against DI water (containing trace amounts of NaCl to lend conductivity). Surprisingly, all salts were found to be negatively charged, more so as their concentrations increased. This collection of results supports the hypothesis that at least some aqueous solutions may contain net charge.
Topics: Salts; Sodium Chloride; Water; Acids; Electric Conductivity; Solutions
PubMed: 36301987
DOI: 10.1371/journal.pone.0275953 -
Journal of Chemical Information and... Jan 2023Water molecules at protein-ligand interfaces are often of significant pharmaceutical interest, owing in part to the entropy which can be released upon the displacement...
Water molecules at protein-ligand interfaces are often of significant pharmaceutical interest, owing in part to the entropy which can be released upon the displacement of an ordered water by a therapeutic compound. Protein structures may not, however, completely resolve all critical bound water molecules, or there may be no experimental data available. As such, predicting the location of water molecules in the absence of a crystal structure is important in the context of rational drug design. Grand canonical Monte Carlo (GCMC) is a computational technique that is gaining popularity for the simulation of buried water sites. In this work, we assess the ability of GCMC to accurately predict water binding locations, using a dataset that we have curated, containing 108 unique structures of complexes between proteins and Food and Drug Administration (FDA)-approved small-molecule drugs. We show that GCMC correctly predicts 81.4% of nonbulk crystallographic water sites to within 1.4 Å. However, our analysis demonstrates that the reported performance of water prediction methods is highly sensitive to the way in which the performance is measured. We also find that crystallographic water sites with more protein/ligand hydrogen bonds and stronger electron density are more reliably predicted by GCMC. An analysis of water networks revealed that more than half of the structures contain at least one ligand-contacting water network. In these cases, displacement of a water site by a ligand modification might yield unexpected results if the larger network is destabilized. Cooperative effects between waters should therefore be explicitly considered in structure-based drug design.
Topics: Water; Ligands; Proteins; Computer Simulation; Pharmaceutical Preparations; Binding Sites; Protein Binding
PubMed: 36469670
DOI: 10.1021/acs.jcim.2c01225 -
The Plant Genome Mar 2020Root anatomical phenes have important roles in soil resource capture and plant performance; however, their phenotypic plasticity and genetic architecture is poorly...
Root anatomical phenes have important roles in soil resource capture and plant performance; however, their phenotypic plasticity and genetic architecture is poorly understood. We hypothesized that (a) the responses of root anatomical phenes to water deficit (stress plasticity) and different environmental conditions (environmental plasticity) are genetically controlled and (b) stress and environmental plasticity are associated with different genetic loci than those controlling the expression of phenes under water-stress and well-watered conditions. Root anatomy was phenotyped in a large maize (Zea mays L.) association panel in the field with and without water deficit stress in Arizona and without water deficit stress in South Africa. Anatomical phenes displayed stress and environmental plasticity; many phenotypic responses to water deficit were adaptive, and the magnitude of response varied by genotype. We identified 57 candidate genes associated with stress and environmental plasticity and 64 candidate genes associated with phenes under well-watered and water-stress conditions in Arizona and under well-watered conditions in South Africa. Four candidate genes co-localized between plasticity groups or for phenes expressed under each condition. The genetic architecture of phenotypic plasticity is highly quantitative, and many distinct genes control plasticity in response to water deficit and different environments, which poses a challenge for breeding programs.
Topics: Gene Expression Regulation; Plant Roots; Soil; Water; Zea mays
PubMed: 33016634
DOI: 10.1002/tpg2.20003 -
Nature Chemistry Sep 2022The solvation of ions changes the physical, chemical and thermodynamic properties of water, and the microscopic origin of this behaviour is believed to be ion-induced...
The solvation of ions changes the physical, chemical and thermodynamic properties of water, and the microscopic origin of this behaviour is believed to be ion-induced perturbation of water's hydrogen-bonding network. Here we provide microscopic insights into this process by monitoring the dissipation of energy in salt solutions using time-resolved terahertz-Raman spectroscopy. We resonantly drive the low-frequency rotational dynamics of water molecules using intense terahertz pulses and probe the Raman response of their intermolecular translational motions. We find that the intermolecular rotational-to-translational energy transfer is enhanced by highly charged cations and is drastically reduced by highly charged anions, scaling with the ion surface charge density and ion concentration. Our molecular dynamics simulations reveal that the water-water hydrogen-bond strength between the first and second solvation shells of cations increases, while it decreases around anions. The opposite effects of cations and anions on the intermolecular interactions of water resemble the effects of ions on the stabilization and denaturation of proteins.
Topics: Anions; Cations; Hydrogen; Spectrum Analysis, Raman; Water
PubMed: 35773490
DOI: 10.1038/s41557-022-00977-2 -
Environment International Dec 2018The microbial safety of swimming pool waters (SPWs) becomes increasingly important with the popularity of swimming activities. Disinfection aiming at killing microbes in... (Review)
Review
The microbial safety of swimming pool waters (SPWs) becomes increasingly important with the popularity of swimming activities. Disinfection aiming at killing microbes in SPWs produces disinfection by-products (DBPs), which has attracted considerable public attentions due to their high frequency of occurrence, considerable concentrations and potent toxicity. We reviewed the latest research progress within the last four decades on the regulation, formation, exposure, and treatment of DBPs in the context of SPWs. This paper specifically discussed DBP regulations in different regions, formation mechanisms related with disinfectants, precursors and other various conditions, human exposure assessment reflected by biomarkers or epidemiological evidence, and the control and treatment of DBPs. Compared to drinking water with natural organic matter as the main organic precursor of DBPs, the additional human inputs (i.e., body fluids and personal care products) to SPWs make the water matrix more complicated and lead to the formation of more types and greater concentrations of DBPs. Dermal absorption and inhalation are two main exposure pathways for trihalomethanes while ingestion for haloacetic acids, reflected by DBP occurrence in human matrices including exhaled air, urine, blood, and plasma. Studies show that membrane filtration, advanced oxidation processes, biodegradation, thermal degradation, chemical reduction, and some hybrid processes are the potential DBP treatment technologies. The removal efficiency, possible mechanisms and future challenges of these DBP treatment methods are summarized in this review, which may facilitate their full-scale applications and provide potential directions for further research extension.
Topics: Disinfection; Humans; Swimming Pools; Water
PubMed: 30392941
DOI: 10.1016/j.envint.2018.10.024 -
Brazilian Journal of Biology = Revista... 2021Water stress executes severe influences on the plant growth and development through modifying physio-chemical properties. Therefore, a field experiment was designed to...
Water stress executes severe influences on the plant growth and development through modifying physio-chemical properties. Therefore, a field experiment was designed to evaluate the antioxidant status and their enhancements strategies for water stress tolerance in chickpea on loam and clay loam soils under agro-ecological conditions of Arid Zone Research Institute, Bahawalpur (29.3871 °N, 71.653 °E) and Cholistan farm near Derawer (28.19°N, 71.80°E) of Southern Punjab, Pakistan during winter 2014-15. Experimental treatments comprised of two chickpea cultivars i.e. Bhakhar 2011 (drought tolerant) and DUSHT (drought sensitive), two water stress levels i.e. water stress at flowering stage and water stress at flowering + pod formation + grain filling stage including well watered (control) and two exogenous application of osmoprotectants i.e. glycine betaine (GB) 20 ppm and proline 10 uM including distilled water (control). Results indicated that water stress at various growth stages adversely affects the growth, yield and quality attributes of both chickpea cultivars. Exogenous application of GB and proline improved the growth, yield and quality parameters of both chickpea cultivars even under water stress conditions. However, superior results were obtained with exogenously applied GB on Bhakhar 2011 under well-watered conditions. Similarly, foliar spray of GB on chickpea cultivar Bhakhar 2011 under stress at flowering + pod formation + grain filling stage produced maximum superoxide dismutase, peroxidase and catalase contents. These results suggested that application of GB mitigates the adverse effects of water stress and enhanced tolerance in chickpea mainly due to higher antioxidant enzymes activity, demonstrating the protective measures of plant cells in stress condition. Hence, antioxidants status might be a suitable method for illustrating water stress tolerance in chickpea.
Topics: Antioxidants; Cicer; Dehydration; Pakistan; Water
PubMed: 33978079
DOI: 10.1590/1519-6984.237809 -
Journal of Colloid and Interface Science Dec 2022Understanding the microscopic driving force of water wetting is challenging and important for design of materials. The relations between structure, dynamics and hydrogen...
HYPOTHESIS
Understanding the microscopic driving force of water wetting is challenging and important for design of materials. The relations between structure, dynamics and hydrogen bonds of interfacial water can be investigated using molecular dynamics simulations.
EXPERIMENTS AND SIMULATIONS
Contact angles at the alumina (0001) and (112‾0) surfaces are studied using both classical molecular dynamics simulations and experiments. To test the superhydrophilicity, the free energy cost of removing waters near the interfaces are calculated using the density fluctuations method. The strength of hydrogen bonds is determined by their lifetime and geometry.
FINDINGS
Both surfaces are superhydrophilic and the (0001) surface is more hydrophilic. Interactions between surfaces and interfacial waters promote a templating effect whereby the latter are aligned in a pattern that follows the underlying lattice of the surfaces. Translational and rotational dynamics of interfacial water molecules are slower than in bulk water. Hydrogen bonds between water and both surfaces are asymmetric, water-to-aluminol ones are stronger than aluminol-to-water ones. Molecular dynamics simulations eliminate the impacts of surface contamination when measuring contact angles and the results reveal the microscopic origin of the macroscopic superhydrophilicity of alumina surfaces: strong water-to-aluminol hydrogen bonds.
Topics: Aluminum Oxide; Hydrogen Bonding; Hydrophobic and Hydrophilic Interactions; Molecular Dynamics Simulation; Water
PubMed: 35964442
DOI: 10.1016/j.jcis.2022.07.164 -
International Journal of Biometeorology Jun 2024Balneotherapy includes practices and methods using medically and legally recognized mineral-medicinal waters, muds and natural gases from natural springs for therapeutic... (Review)
Review
Balneotherapy includes practices and methods using medically and legally recognized mineral-medicinal waters, muds and natural gases from natural springs for therapeutic purposes. One of the most widely used method in balneotherapy is bathing with thermal mineral water. In the course of the years, scientific community has produced an increasing number of evidences that this practice is an effective method for treating signs and symptoms of several pathologies such as rheumatic, cardiovascular and dermatological diseases. This systematic review is aimed at evaluating the effect of balneotherapy with thermal water baths as a treatment to manage signs and symptoms of patients affected by all types of dermatological diseases. The systematic review was conducted according to the PRISMA Statement, and its protocol was registered on PROSPERO platform (CRD42022295913). The research was performed on the databases Pubmed, Scopus, Web of Science and Cochrane. We included clinical trials evaluating the effects of balneotherapy using thermal mineral water baths for managing dermatological diseases in humans, published in English and Italian language. Eight studies were included, seven of them enrolled adults affected by psoriasis and one studied atopic dermatitis patients. The common result of all the articles included was a clear improvement of signs and symptoms of psoriasis and eczematous diseases after use of thermal mineral water baths. These effects seem to be strictly related to physical and chemical properties of thermal water used for balneotherapy. However, studies in this field are still limited to support robust evidence of the effectiveness of balneotherapy using thermal mineral water baths and often their quality is low. Thus, new clinical studies need to be carried out, using more correct methods for conducting the studies and for processing statistical data.
Topics: Humans; Balneology; Mineral Waters; Skin Diseases; Baths; Dermatitis, Atopic; Psoriasis
PubMed: 38530467
DOI: 10.1007/s00484-024-02649-x -
Proceedings of the National Academy of... Oct 2016The Pleistocene global dispersal of modern humans required the transit of arid and semiarid regions where the distribution of potable water provided a primary constraint...
The Pleistocene global dispersal of modern humans required the transit of arid and semiarid regions where the distribution of potable water provided a primary constraint on dispersal pathways. Here, we provide a spatially explicit continental-scale assessment of the opportunities for Pleistocene human occupation of Australia, the driest inhabited continent on Earth. We establish the location and connectedness of persistent water in the landscape using the Australian Water Observations from Space dataset combined with the distribution of small permanent water bodies (springs, gnammas, native wells, waterholes, and rockholes). Results demonstrate a high degree of directed landscape connectivity during wet periods and a high density of permanent water points widely but unevenly distributed across the continental interior. A connected network representing the least-cost distance between water bodies and graded according to terrain cost shows that 84% of archaeological sites >30,000 y old are within 20 km of modern permanent water. We further show that multiple, well-watered routes into the semiarid and arid continental interior were available throughout the period of early human occupation. Depletion of high-ranked resources over time in these paleohydrological corridors potentially drove a wave of dispersal farther along well-watered routes to patches with higher foraging returns.
Topics: Archaeology; Australia; Geography; Human Migration; Humans; Models, Theoretical; Water; Water Resources
PubMed: 27671630
DOI: 10.1073/pnas.1608470113