Plasma membrane tension regulates many key cellular processes. It is modulated by, and can modulate, membrane trafficking. However, the cellular pathway(s) involved in this interplay is poorly understood. Here we find that, among a number of endocytic processes operating simultaneously at the cell surface, a dynamin independent pathway, the CLIC/GEEC (CG) pathway, is rapidly and specifically upregulated upon a sudden reduction of tension. Moreover, inhibition (activation) of the CG pathway results in lower (higher) membrane tension. However, alteration in membrane tension does not directly modulate CG endocytosis. This requires vinculin, a mechano-transducer recruited to focal adhesion in adherent cells. Vinculin acts by controlling the levels of a key regulator of the CG pathway, GBF1, at the plasma membrane. Thus, the CG pathway directly regulates membrane tension and is in turn controlled via a mechano-chemical feedback inhibition, potentially leading to homeostatic regulation of membrane tension in adherent cells.

Access to clean and safe water supply remains inadequate in many developing countries. One of the key challenges is to remove pathogenic bacteria from the water supply via effective water disinfection technologies to prevent the spread of diseases and to ensure the safety of consumers. Herein, a highly effective point-of-use (on-demand) water disinfection technology, in the form of a polymeric scaffold called macroporous antimicrobial polymeric gel (MAPG), is demonstrated. MAPG is easy to fabricate, completely organic and possess inherent antimicrobial property which makes it non-reliant on inorganic compounds such as silver where the long-term toxicity remains unknown. MAPG is highly bactericidal and can disinfect bacteria-contaminated water (ca. 108 CFU mL−1) at a capacity of about >50 times the mass of the organic material used, inactivating >99% of both Gram-negative and Gram-positive bacteria including Escherichia coli, Vibrio cholerae and Staphylococcus aureus within 20 minutes of treatment. When fabricated in a syringe, MAPG eliminates E. coli from contaminated water source by >8.0 log10 reduction in bacteria counts (i.e., no viable bacteria were detected after treatment), and the syringe can be reused multiple times without losing potency. The MAPG technology is not only restricted to water disinfection but may also be applicable in other bacteria inactivation applications.

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Organic−inorganic hybrid lead halide perovskites have shown significant progress in the last few years having achieved efficiencies over 25% at the lab scale. The sequential deposition technique has provided a robust approach in the perovskite film fabrication. However, obtaining a reproducible and quality perovskite film has always been challenging because of the highly crystalline and ordered (001) oriented underlying PbI 2 film. Here, we report a simple solution approach to fabricate a PbI 2 residue-free, superior grade perovskite film by using a compositional engineered PbI 2 −precursor solution. We demonstrate that the Pb−precursor film crystallized into a R-centered Hexagonal metric lattice with (h0l), (hk0), and (00l) orientations provides a more efficient and quicker conversion into perovskites compared to conventional (001) oriented 2H-PbI 2 . A porous and multi-oriented PbI 2 film is prepared by rationally incorporating a volumetric fraction of Pb(Ac) 2 •3H 2 O in the typical PbI 2 /dimethylformamide precursor solution, which significantly improves the surface features of PbI 2 as well as the structural properties. As a result, a compact, smooth, and large grain perovskite can be obtained by accomplishing a full conversion with comparatively much less reaction time. Furthermore, a comprehensive mechanism of structural modification of PbI 2 and the role of its orientation in ameliorating the reaction kinetics has been demonstrated.

Segmentation of foreground and background has been an important research problem arising out of many applications including video surveillance. A method commonly used for segmentation is "background subtraction" or thresholding the difference between the estimated background image and current image. Adaptive Gaussian mixture based background modelling has been proposed by many researchers for increasing the robustness against environmental changes. However, all these methods, being computationally intensive, need to be optimized for efficient and real-time performance especially at a higher image resolution. In this paper, we propose an improved foreground/background segmentation method which uses Experiential Sampling technique to restrict the computational efforts in the region of interest. We exploit the fact that the region of interest in general is present only in a small part of the image, therefore, the attention should only be focused in those regions. The proposed method shows a significant gain in processing speed at the expense of minor loss in accuracy. We provide experimental results and detailed analysis to show the utility of our method.

Sequential deposition route is widely investigated in fabricating perovskite thin films for state‐of‐the‐art perovskite photovoltaics. However, concerns such as lower morphological control, phase purity, and remnant unreacted salts methylammonium iodide (MAI and PbI2) are raised, which can significantly deteriorate optoelectronic properties, hence the operational durability of the devices. Herein, a facile two‐step method to prepare high‐quality perovskite thin films with reproducibility is reported, as‐spun PbI2 is annealed at varying thermal input under controlled rate, and a trend in converted perovskite film properties is noted. Specifically, PbI2 thin film annealed at 200 °CC results in 20x intensified crystallinity with pinholes free and a subsequent reduction in the crystal microstrain. In addition, it provides higher surface roughness to load more MAI [in iso‐propyl alcohol (IPA)]; therefore, a higher perovskite conversion is achieved. This method enables a significant efficiency enhancement in the treated sample (Pero@PbI2‐200 °C) as compared with controlled film; it retains around 90% initial efficiency after 384 h of ambient exposure. Furthermore, a facile intermediate solvent treatment method to gain the complete conversion of PbI2 into perovskite is also reported. This study highlights the importance of morphological control in governing optoelectronic properties, hence the efficiency and stability of perovskite solar cells.

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Butadiene rubber (BR) is one of the most useful and second most produced rubber worldwide. Polymerization of 1,3-butadiene (BD) is a highly stereospecific reaction that offers a wide variety of BR with different microstructures and influences the fundamental properties of the rubber. Since the first successful polymerization of conjugated diene using the Ziegler–Natta–based catalyst (TiCl4 or TiCl3 with aluminum alkyls) in 1954, the research on producing synthetic rubber with an appropriate catalyst system has been accelerated. Subsequently, various research groups are actively engaged in designing active catalyst systems based on a suitable combination of transition metal complexes with alkyl-aluminum and successfully using them in BD polymerization. Although various scientific inventions have proven their significance for the production of high-quality BR, with the rising demands in improving the quality of the product, research on developing new catalyst systems with enhanced catalytic activity and high stereoselectivity is still in progress. The present review focuses on the synthesis of BR using various transition metal catalysts and discusses their microstructures. The catalysts based on new-generation metal complexes with phosphorus, nitrogen, and oxygen donor ligands (e.g., phosphines, imines, 1,10-phenanthroline, and imino-pyridines) have been introduced. The role that catalysts play in the production of BR with different microstructures (i.e., high-cis, high-trans or low-cis, low-trans polybutadiene) has also been described. The combination of catalyst (transition metal complex) and suitable co-catalyst (alkyl-aluminum) is the major factor influencing the reaction and microstructure of the resulting polymer. This report focuses on the effect of transition metal catalysts (i.e., lithium [Li], titanium [Ti], zirconium [Zr], iron [Fe], cobalt [Co], nickel [Ni], and neodymium [Nd]) on the activity and stereoselectivity of polymers such as 1,4-cis-, 1,4-trans-, and 1,2-vinyl-polybutadiene.