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Polysaccharides are abundantly available from farm, forest, and microbial resources. They are used in myriad applications. It has been established in the authors' laboratory that their performance is enhanced considerably on purification, grafting by polyacrylamide (PAM), and subsequent hydrolysis as well as cationization. The most significant performance is enhanced in flocculation where it has been found that the modified polysaccharides outperform existing flocculants in national and international markets. Similar effects are observed in their performance in turbulent drag reduction (DR), percolation, and rheology. The present article outlines the details of materials, mechanisms, and practical applications of these novel materials.saccharides may have many low-molecular-weight impurities. The biodegradability of polysaccharides reduces their shelf life and needs to be suitably controlled. In various applications, their required dosages are large and their solutions and flocs lose stability and strength because of biodegradability. However, by purification [5], grafting [5], hydrolysis [6], and cationization [7], useful polymeric materials can be developed for varied applications.Effluent disposal is a major problem nowadays all over the world. Industrial development has created hazards and environmental problems. Hence, environmental concern and depletion of raw material resources have forced scientists and technologists to develop materials from renewable agricultural and plant resources to protect the environment from pollution.Recycling of domestic wastewater, industrial effluents, and mineral-processing effluents has been accepted by the application of synthetic flocculants for solid-liquid separation due to economic and environmental considerations all over the world [8][9][10]. When polymers are involved in a solid-liquid separation by an aggregation process of colloidal particles, the process is termed "flocculation" [10]. In general, flocculation is caused by the addition of a minute quantity of chemicals known as "flocculants". Both inorganic and organic flocculants are used in various kinds of flocculation phenomena [11]. Among the inorganic flocculants, the salts of multivalent metals like aluminum and iron are mostly used. The organic flocculants are essentially polymeric in nature. Both synthetic and natural water-soluble polymers are used as flocculants [8][9][10][11]. Some of the most important types of synthetic polymers are polyacrylamide (PAM), poly(acrylic acid), poly(styrene sulfonic acid), poly(diallyl dimethyl ammonium chloride) (DADMAC), etc., the synthetic effluents are available in all three ionic formscationic, anionic, and nonionic. Among the natural polymers, starch, guar gum, alginates, and products based on chitin, glue, and gelatin are used as flocculants and retention aids. The extensive use of polymers as flocculants is due to their low dosage (1-5 ppm), inertness to pH changes, formation of large cohesive flocs, and versatile tailorability. Large tonnage use of inorganic comp...

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<b><i>Background:</i></b> Hemorrhagic transformation (HT) is a complication that occurs spontaneously or after thrombolysis in acute ischemic stroke (AIS) and can increase morbidity and mortality. The association of biomarkers with the risk of HT has been variably reported. We conducted a systematic review of the literature and meta-analysis and sought to compare blood biomarkers associated with HT and its subtypes by evaluating its predictability and correlation with outcome in AIS. <b><i>Methods:</i></b> The study protocol was registered in the PROSPERO database (CRD42020201334) and adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Among 2,230 articles identified from Cochrane Library, PubMed, and Web of Science databases, 30 quality-appraised articles were found eligible. Meta-analysis was conducted for matrix metalloproteinase-9 (MMP-9), cellular fibronectin (c-Fn), ferritin, S100 calcium-binding protein B (S100B), and neutrophil-lymphocyte ratio (NLR). We also reviewed biomarkers for correlation with the functional outcome at 90 days from stroke onset (poor outcome modified Rankin scale &#x3e;2). <b><i>Results:</i></b> The pooled diagnostic odds ratio (DOR_pooled) was the highest for baseline c-Fn levels (299.253 [95% CI, 20.508–4,366.709]), followed by MMP-9 (DOR_pooled, 29.571 [95% CI 17.750–49.267]) and ferritin (DOR_pooled, 24.032 [95% CI 2.557–225.871]). However, wide confidence intervals for ferritin and c-Fn suggested lesser reliability of the markers. Patients with MMP-9 levels ≥140 ng/mL were 29.5 times at higher risk of developing symptomatic HT after AIS (area under the curve = 0.881). S100B (DOR_pooled, 6.286 [95% CI, 1.861–21.230]) and NLR (DOR_pooled, 5.036 [95% CI, 2.898–8.749]) had lower diagnostic accuracies. Among the markers not included for meta-analysis, caveolin-1, thrombin-activated fibrinolysis inhibitor, plasminogen activator inhibitor-1, and soluble ST2 were highly sensitive. Elevated levels of MMP-9, ferritin, and NLR were found to be associated with poor functional outcomes and mortality. <b><i>Conclusion:</i></b> Of the 5 biomarkers, there was enough evidence that MMP-9 has higher diagnostic accuracy for predicting the risk of HT before thrombolysis. MMP-9, ferritin, and NLR also predicted poor short-term outcomes.

An electrothermal flow induced chaotic mixing in microfluidic systems is studied analytically and numerically. The flow is induced due to the Coulombic and dielectric forces arising from the variation of the dielectric properties with respect to the temperature in the presence of an electric field. The numerical model is validated using an analytical solution derived for basic flow patterns in a simplified geometry. The computational model has been used to illustrate the mixing in microcavity and T-sensor constructs. The simulations predict the chaotic nature of the mixing process, where the material interface evolution shows exponential growth.