Surface-attached bacterial biofilms are self-replicating active liquid crystals and the dominant form of bacterial life on earth (1-4). In conventional liquid crystals and solid-state materials, the ...interaction potentials between the molecules that comprise the system determine the material properties. However, for growth-active biofilms it is unclear whether potential-based descriptions can account for the experimentally observed morphologies, and which potentials would be relevant. Here, we overcame previous limitations of single-cell imaging techniques (5,6) to reconstruct and track all individual cells inside growing three-dimensional (3D) biofilms with up to 10,000 individuals. Based on these data, we identify, constrain, and provide a microscopic basis for an effective cell-cell interaction potential, which captures and predicts the growth dynamics, emergent architecture, and local liquid crystalline order of
biofilms. Furthermore, we show how external fluid flows control the microscopic structure and 3D morphology of biofilms. Our analysis implies that local cellular order and global biofilm architecture in these active bacterial communities can arise from mechanical cell-cell interactions, which cells can modulate by regulating the production of particular matrix components. These results establish an experimentally validated foundation for improved continuum theories of active matter and thereby contribute to solving the important problem of controlling biofilm growth.
Dye sensitized solar cell (DSSC) is one of the most capable solar cell devices to transform sunlight directly into electricity. DSSC can revolutionize the solar energy industry due to its unique ...features and has attracted a lot of attention towards this alternative solar cell technology. DSSC can be manufactured with low-cost materials, easy manufacturing methods, less toxic materials, and most important, allocating feasibility of solar cell fabrication at a low cost as compared to traditional solar cells. The NREL certified power conversion efficiency (PCE) for DSSC is 12.3%, whereas the lab-scale PCE has reached 14.3%. In this paper, we present an introduction and classification of PV technologies and a brief description of DSSC development particularly ruthenium complexes based DSSC. This review also presents the structure, operational principle of DSSC and includes the essential criteria for the components of DSSC to offer a vision for the design of highly efficient DSSC. The research progress made in sensitizers especially in ruthenium complexes based have been summarized with their efficiency, dye structure, short circuit current (Isc), open circuit voltage (Voc) and fill factor (FF).
The importance of gut microbiota in human health and pathophysiology is undisputable. Despite the abundance of metagenomics data, the functional dynamics of gut microbiota in human health and disease ...remain elusive. Urolithin A (UroA), a major microbial metabolite derived from polyphenolics of berries and pomegranate fruits displays anti-inflammatory, anti-oxidative, and anti-ageing activities. Here, we show that UroA and its potent synthetic analogue (UAS03) significantly enhance gut barrier function and inhibit unwarranted inflammation. We demonstrate that UroA and UAS03 exert their barrier functions through activation of aryl hydrocarbon receptor (AhR)- nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent pathways to upregulate epithelial tight junction proteins. Importantly, treatment with these compounds attenuated colitis in pre-clinical models by remedying barrier dysfunction in addition to anti-inflammatory activities. Cumulatively, the results highlight how microbial metabolites provide two-pronged beneficial activities at gut epithelium by enhancing barrier functions and reducing inflammation to protect from colonic diseases.
The COVID‐19 disease caused by the SARS‐CoV‐2 has emerged as a worldwide pandemic and caused huge damage to the lives and economy of more than hundred countries. As on May 10, 2020, more than ...4,153,300 people stand infected from the virus due to an unprecedented rate of transmission and 282,700 have lost their lives because of the disease. In this context, medicinal plants may provide a way to treat the disease by targeting specific essential proteins of the virus. We screened about 51 medicinal plants and found that Tea (Camellia sinensis) and Haritaki (Terminalia chebula) has potential against SARS‐COV‐2 3CLpro, with an IC50 for Green Tea as 8.9 ± 0.5 μg/ml and Haritaki 8.8 ± 0.5 μg/ml. The in‐silico studies suggested that Tea component Thearubigins binds to the cysteine 145 of protease active site and could be a pharmacoactive molecule. We predict that the inhibition in protease activity may be able to halt the SARS‐CoV‐2 replication cycle and therefore, we propose Green Tea, Black Tea, and Haritaki plant extracts as potential therapeutic candidates for SARS‐CoV‐2 infection. Further investigation on role of bioactive constituents of extracts is needed to establish the molecular basis of inhibition and towards expedited drug discovery.
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•Formulation of cellulosic derivative by exploiting radical polymerization method (RPM) is discussed.•Activation of cellulosic texture has been described.•Monomer’s grafting onto ...cellulosic texture from suitable initiators have been elaborated.•Radiation indulged system promote the performance of RPM.•Controlled radical polymerization triggers the cellulose grafting reaction in block polymerization style.
Cellulose is an abundant organic substance found in natural polymer, consists of a linear chain of β glucose residue, which ties from the 1, 4 linkage. Owing to their incredible properties such as bio-renewable, specific tensile strength and bio-degradable, it is being enormously using as a paperboard, drug delivery, fiber production, food packing material, sensitized solar cell, biosorbent, pickering emulsion stabilizer, and battery separator in the modern age of the lithium-ion battery. This review principally points out the radical polymerization method (RPM) for fabricating cellulose derivative. By exploiting RPM, new and improved properties indulging polymer composite of cellulose can successfully fix up by the reaction with the small organic fragment (monomer) such as a methacrylate, methacrylamide, styrene, and butadiene, etc. Radical polymerization has been striking for a long time, due to their procurable process-ability among all the polymerization methods. The most commonly used initiators such as Fenton's reagent, potassium persulfate, and ceric ammonium nitrate are being using to engender free radicals on the cellulose backbone. Other free radical generating techniques like radiation technique (UV + photoinitiator, gamma radiation), plasma treatment, and controlled radical polymerization are being using for grafting purposes. The review summarizes to traditional grafting strategy by common initiators and currently utilizing controlled radical polymerization (CRP) chemistry for polymer synthesis. These methods allow for the formation of functional cellulose, which may possess renovated physical and chemical properties.
Coordinated dynamics of individual components in active matter are an essential aspect of life on all scales. Establishing a comprehensive, causal connection between intracellular, intercellular, and ...macroscopic behaviors has remained a major challenge due to limitations in data acquisition and analysis techniques suitable for multiscale dynamics. Here, we combine a high-throughput adaptive microscopy approach with machine learning, to identify key biological and physical mechanisms that determine distinct microscopic and macroscopic collective behavior phases which develop as Bacillus subtilis swarms expand over five orders of magnitude in space. Our experiments, continuum modeling, and particle-based simulations reveal that macroscopic swarm expansion is primarily driven by cellular growth kinetics, whereas the microscopic swarming motility phases are dominated by physical cell–cell interactions. These results provide a unified understanding of bacterial multiscale behavioral complexity in swarms.
In nature, bacteria primarily live in surface-attached, multicellular communities, termed biofilms
. In medical settings, biofilms cause devastating damage during chronic and acute infections; ...indeed, bacteria are often viewed as agents of human disease
. However, bacteria themselves suffer from diseases, most notably in the form of viral pathogens termed bacteriophages
, which are the most abundant replicating entities on Earth. Phage-biofilm encounters are undoubtedly common in the environment, but the mechanisms that determine the outcome of these encounters are unknown. Using Escherichia coli biofilms and the lytic phage T7 as models, we discovered that an amyloid fibre network of CsgA (curli polymer) protects biofilms against phage attack via two separate mechanisms. First, collective cell protection results from inhibition of phage transport into the biofilm, which we demonstrate in vivo and in vitro. Second, CsgA fibres protect cells individually by coating their surface and binding phage particles, thereby preventing their attachment to the cell exterior. These insights into biofilm-phage interactions have broad-ranging implications for the design of phage applications in biotechnology, phage therapy and the evolutionary dynamics of phages with their bacterial hosts.
Obg-like ATPase 1 (OLA1) protein has GTP and ATP hydrolyzing activities and is important for cellular growth and survival. The human OLA1 gene maps to chromosome 2 (locus 2q31.1), near Titin (TTN), ...which is associated with familial dilated cardiomyopathy (DCM). In this study, we found that expression of OLA1 was significantly downregulated in failing human heart tissue (HF) compared to non-failing hearts (NF). Using the Sanger sequencing method, we characterized the human OLA1 gene and screened for mutations in the OLA1 gene in patients with failing and non-failing hearts. Among failing and non-failing heart patients, we found 15 different mutations in the OLA1 gene, including two transversions, one substitution, one deletion, and eleven transitions. All mutations were intronic except for a non-synonymous 5144A>G, resulting in 254Tyr>Cys in exon 8 of the OLA1 gene. Furthermore, haplotype analysis of these mutations revealed that these single nucleotide polymorphisms (SNPs) are linked to each other, resulting in disease-specific haplotypes. Additionally, to screen the 254Tyr>Cys point mutation, we developed a cost-effective, rapid genetic screening PCR test that can differentiate between homozygous (AA and GG) and heterozygous (A/G) genotypes. Our results demonstrate that this PCR test can effectively screen for OLA1 mutation-associated cardiomyopathy in human patients using easily accessible cells or tissues, such as blood cells. These findings have important implications for the diagnosis and treatment of cardiomyopathy.
The diacylglycerol lipases (DAGLs) hydrolyse diacylglycerol to generate 2-arachidonoylglycerol (2-AG), the most abundant ligand for the CB1 and CB2 cannabinoid receptors in the body. DAGL-dependent ...endocannabinoid signalling regulates axonal growth and guidance during development, and is required for the generation and migration of new neurons in the adult brain. At developed synapses, 2-AG released from postsynaptic terminals acts back on presynaptic CB1 receptors to inhibit the secretion of both excitatory and inhibitory neurotransmitters, with this DAGL-dependent synaptic plasticity operating throughout the nervous system. Importantly, the DAGLs have functions that do not involve cannabinoid receptors. For example, 2-AG is the precursor of arachidonic acid in a pathway that maintains the level of this essential lipid in the brain and other organs. This pathway also drives the cyclooxygenase-dependent generation of inflammatory prostaglandins in the brain, which has recently been implicated in the degeneration of dopaminergic neurons in Parkinson's disease. Remarkably, we still know very little about the mechanisms that regulate DAGL activity—however, key insights can be gleaned by homology modelling against other α/β hydrolases and from a detailed examination of published proteomic studies and other databases. These identify a regulatory loop with a highly conserved signature motif, as well as phosphorylation and palmitoylation as post-translational mechanisms likely to regulate function.
Compared to 2017, India achieved a significant reduction in malaria cases in 2020. Madhya Pradesh (MP) is a tribal dominated state of India with history of high malaria burden in some districts. ...District Mandla of MP state showed a considerable decline in malaria cases between 2000 and 2013, except in 2007. Subsequently, a resurgence of malaria cases was observed during 2014 and 2015. The Malaria Elimination Demonstration Project (MEDP) was launched in 2017 in Mandla with the goal to achieve zero indigenous malaria cases. This project used: (1) active surveillance and case management using T4 (Track fever, Test fever, Treat patient, and Track patient); (2) vector control using indoor residual sprays and long-lasting insecticidal nets; (3) information education communication and behaviour change communication; and (4) regular monitoring and evaluation with an emphasis on operational and management accountability. This study has investigated malaria prevalence trends from 2008 to 2020, and has predicted trends for the next 5 years for Mandla and its bordering districts.
The malaria prevalence data of the district Mandla for the period of January 2008 to August 2017 was obtained from District Malaria Office (DMO) Mandla and data for the period of September 2017 to December 2020 was taken from MEDP data repository. Further, the malaria prevalence data for the period of January 2008 to December 2020 was collected from DMOs of the neighbouring districts of Mandla. A univariate time series and forecast analysis was performed using seasonal autoregressive integrated moving average model.
Malaria prevalence in Mandla showed a sharp decline - 87% (95% CI - 90%, - 84%) from 2017 to 2020. The malaria forecast for Mandla predicts zero cases in the next 5 years (2021-2025), provided current interventions are sustained. By contrast, the model has forecasted a risk of resurgence of malaria in other districts in MP (Balaghat, Dindori, Jabalpur, Seoni, and Kawardha) that were not the part of MEDP.
The interventions deployed as part of MEDP have resulted in a sustainable zero indigenous malaria cases in Mandla. Use of similar strategies in neighbouring and other malaria-endemic districts in India could achieve similar results. However, without adding extra cost to the existing intervention, sincere efforts are needed to sustain these interventions and their impact using accountability framework, data transparency, and programme ownership from state to district level.
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