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Cholera has been extremely pervasive during the past four decades and continues to remain a significant public health concern. The disease has plagued humankind in the form of seven pandemics since the last two centuries. There is considerable scientific evidence based on research on cholera and its etiologic agent Vibrio cholerae , however we are still unable to accurately forecast and pre-empt the occurrence of cholera outbreaks. The commentary discusses the contrasts and contradictions of cholera, its control and its unpredictable nature. Through a multi-sectoral approach and broad stakeholder collaboration cholera control is possible with meticulous country-level planning for early detection and response to outbreaks. The commentary reiterates that every potential death on account of cholera is preventable because of the available knowledge and tools to effectively prevent and treat cholera. [ABSTRACT FROM AUTHOR]

Although enzymes are gifted with unique and unprecedented catalytic activity and selectivity over a wide range of pollutants, still their stability related issues often hinder their application in real environmental conditions. In this study, agro-industrially produced crude laccase was concentrated using ultrafiltration. Crude laccase was immobilized on pine wood (BC-PW), pig manure (BC-PM) and almond shell (BC-AS) biochar microparticles. Immobilization of laccase was investigated at various laccase activities on micro-biochars and the release (desorption) of the enzyme has been studied. It was observed that for all the biochars, as the initial concentration of laccase increased in the crude solution, the binding capacity and as result immobilization efficiency also increased. BC-PM was found to be the most effective (31.4 ± 3.1 U g −1 ) at 10 U mL −1 of enzyme activity followed by BC-AS (24.3 ± 4.8 U g −1 ) and BC-PW (14.58 ± 3.3 U g −1 ). In addition, the biochars were functionalized with citric acid for possible surface modifications and the effect of biochars for the adsorption of enzymes has been investigated. Isotherm studies of enzyme loading onto biochar established homogeneous monolayer adsorption as the major mechanism. The desorption of laccase from all biochars followed pseudo-second-order model. Immobilized laccase exhibited superior storage ability and shelf-life which were three times higher than free laccase. Finally, the immobilized laccase was used for the degradation of micropollutant, DCF and near 100% removal was obtained within 5 h at an environmentally relevant concentration (500 μg L −1 ). [ABSTRACT FROM AUTHOR]

Biochars were prepared from feedstocks pinewood and pig manure. Biochar microparticles obtained through grinding were evaluated for the removal of emerging contaminant diclofenac (DCF) and the underlying mechanism were thoroughly studied. Characterization of biochar was carried out using particle size analyzer, SEM, BET, FT-IR, XRD, XPS and zeta potential instrument. Pig manure biochar (BC-PM) exhibited excellent removal efficiency (99.6%) over pine wood biochar (BC-PW) at 500 µg L −1 of DCF (environmentally significant concentration). Intraparticle diffusion was found to be the major process facilitated the adsorption. BC-PW followed pseudo first-order kinetics whereas BC-PM followed pseudo second-order kinetics. Pine wood biochar was largely affected by pH variations whereas for pig manure biochar, pH effects were minimal owing to its surface functional groups and DCF hydrophobicity. Thermodynamics, presence of co-existing ions, initial adsorbate concentration and particles size played substantial role in adsorption. Various isotherms models were also studied and results are presented. [ABSTRACT FROM AUTHOR]

Diclofenac (DCF) is a prevalent anti-inflammatory drug used throughout the world. Intensive researches carried out in the past few decades have confirmed the global ubiquity of DCF in various environmental compartments. Its frequent occurrence in freshwater environments and its potential toxicity towards several organisms such as fish and mussels makes DCF an emerging environmental contaminant. At typical detected environmental concentrations, the drug does not exhibit toxic effects towards living organisms, albeit chronic exposure may lead to severe effects. For DCF, about 30–70% removal has been obtained through the conventional treatment system in wastewater treatment plant being the major primary sink. Thus, the untreated DCF will pass to surface water. DCF can interact with other inorganic contaminants in the environment particularly in wastewater treatment plant, such as metals, organic contaminants and even with DCF metabolites. This process may lead to the creation of another possible emerging contaminant. In the present context, environmental fate of DCF in different compartments such as soil and water has been addressed with an overview of current treatment methods. In addition, the toxicity concerns regarding DCF in aquatic as well as terrestrial environment along with an introduction to the metabolites of DCF through consumption as well as abiotic degradation routes are also discussed. Further studies are required to better assess the fate and toxicological effects of DCF and its metabolites and must consider the possible interaction of DCF with other contaminants to develop an effective treatment method for DCF and its traces. [ABSTRACT FROM AUTHOR]

Biochar microparticles were prepared from three different types of biochar, derived from waste materials, such as pine wood (BC-PW), pig manure (BC-PM) and cardboard (BC-PD) under various pyrolysis conditions. The microparticles were prepared by dry grinding and sequential sieving through various ASTM sieves. Particle size and specific surface area were analyzed using laser particle size analyzer. The particles were further characterized using scanning electron microscope (SEM). The adsorption capacity of each class of adsorbent was determined by methylene blue adsorption tests in comparison with commercially available activated carbon. Experimental results showed that dye adsorption increased with initial concentration of the adsorbate and biochar dosage. Biochar microparticles prepared from different sources exhibited improvement in adsorption capacity (7.8 ± 0.5 mg g −1 to 25 ± 1.3 mg g −1 ) in comparison with raw biochar and commercially available activated carbon. The adsorption capacity varied with source material and method of production of biochar. The maximum adsorption capacity was 25 mg g −1 for BC-PM microparticles at 25 °C for an adsorbate concentration of 500 mg L −1 in comparison with 48.30 ± 3.6 mg g −1 for activated carbon. The equilibrium adsorption data were best described by Langmuir model for BC-PM and BC-PD and Freundlich model for BC-PW. [ABSTRACT FROM AUTHOR]

Abstract: High-pressure X-ray diffraction and Raman studies on holmium sesquioxide (Ho2O3) have been carried out up to a pressure of ∼17GPa in a diamond-anvil cell at room temperature. Holmium oxide, which has a cubic or bixbyite structure under ambient conditions, undergoes an irreversible structural phase transition at around 9.5GPa. The high-pressure phase has been identified to be low symmetry monoclinic type. The two phases coexist to up to about 16GPa, above which the parent phase disappears. The high-pressure laser-Raman studies have revealed that the prominent Raman band ∼370cm−1 disappears around the similar transition pressure. The bulk modulus of the parent phase is reported. [Copyright &y& Elsevier]

Surface functional groups on biochars are one of the key features which determine biochar properties and their potential applications. In this study, biochars obtained from various feedstocks, such as pinewood, pig manure, and almond shell were functionalized using organic acids, such as acetic acid, citric acid, tartaric acid, oxalic acid, and malic acid. For pinewood biochar, citric and acetic acids were found to be effective and citric acid was more efficient in terms of grafting –COOH groups (40% improvement). Tartaric, oxalic and citric acids were found to be effective based on FTIR data for pig manure biochar, however, the effect of acids were minimal on functionalization. Similarly, citric and oxalic acids were found to be effective for almond shell biochar. Citric acid functionalization increased total acidic functional groups by 23%, 10%, and 26%, respectively for pinewood, pig manure, and almond shell. Citric acid-functionalized biochars showed higher removal of the environmentally relevant concentration (500 μg L−1) of emerging contaminant, diclofenac (DCF). For pinewood biochar, at equilibrium, the diclofenac removal increased from 65 to 80%. For almond shell biochar, under similar conditions, the diclofenac removal efficiency increased from 58 to 84%. Image 100566 • Micro-biochars were functionalized using various organic acids. • Feedstock and organic acids were influential in functionalization. • Functionalized biochars showed improved and new functional groups on the surface. • Functionalized biochars exhibited enhanced adsorption potential towards diclofenac. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Biochar microparticles are thoroughly characterized. • Adsorption of 4.10 mg g−1 was observed for diclofenac with pig manure biochar. • Influence of porous and surface characteristics on adsorption was investigated. • Immobilized laccase on pinewood biochar enhanced degradation of diclofenac. • Column studies and dynamic modeling gives further insight for scaling up. Abstract Laccase bound biochar as a fixed-bed column for the removal of emerging contaminant, diclofenac (DCF) provides novel insights into valorization of waste materials, application of environmentally benign sorbents and removal of DCF with possibilities of scaling up for larger applications. Micro-biochar prepared from pine wood (BC-PW) and pig manure (BC-PM) were evaluated for the removal of DCF at environmentally relevant concentrations under continuous fixed–fed column operating conditions. Biochars were characterized for particle size, total metals, elemental composition, surface area, porosity, surface texture, and functional groups. The ligninolytic enzyme laccase was immobilized on micro-biochars and tested for removal/biodegradation of DCF under optimized conditions obtained from adsorption column experiments At an environmentally relevant concentration (500 μg L−1), BC-PM exhibited an adsorption capacity of 4.10 mg g-1 with bed mass: 2 g, flow rate: 2 mL min-1 and at pH: 6.5. For all biochars, uptake of DCF through a fixed-bed column was dependent on the mass of adsorbent (bed height) and DCF concentration. Adsorption capacity decreased with increasing bed height whereas increased with increasing DCF concentration. The Thomas and Yoon–Nelson models were successfully applied to predict the breakthrough curves, indicating that these models were used for designing and scaling – up fixed-bed biochar columns. [ABSTRACT FROM AUTHOR]

Aberropia leads to decrease in image quality due to higher order aberrations (HOA). Correction of these HOA poses a great challenge to clinicians. A case report is presented here where a 30 year old male visited with complaints of cloudy vision, diplopia in reduced illumination along with inferior vertical elongation of light during night time in the right eye since 6 years. The unaided visual acuity was found to be 0.0 Log MAR units and near acuity was N6. The patient did not accept any correction in subjective refraction. The aberrometry findings revealed vertical trefoil and vertical coma of -0.33 μm and 0.53 μm in the right eye and -0.07 μm and 0.12 μm in the left eye. Orbscan revealed a difference of 30 μm and 25 μm between the anterior and posterior float for the right and left eye respectively. Due to the significant increase in irregular astigmatism, vertical coma and vertical trefoil in the right eye, rigid gas permeable lenses and Rose K lenses were tried, but the symptoms did not reduce. This was due to the increase in posterior corneal astigmatism as the posterior float was more than 25 μm in the right eye which led to a diagnosis of early keratoconus. As the decrease in pupil size reduces HOA, a pin hole (2.5 mm pupil) soft contact lens was tried which reduced the symptoms. Hence a novel method is proposed to eliminate HOA which corrects aberropia by using pin hole soft contact lenses. [ABSTRACT FROM AUTHOR]