Influence of industrial by-products on the behavior of geopolymer concrete for sustainable development

433-445Carbon dioxideemission in cement industries is a great concern for environment, which is increasing day by day. Therefore, it is very essential to find a possible material that can be used as a replacement of cement. Geopolymer concrete is a kind of inorganic concrete elucidating the formal usage of industrial and natural waste in either single or combined form. Geopolymers are amorphous covalently bonded by a 3D network of inorganic molecules of aluminosilicate material. The formation of geopolymer concrete is greatly influenced by several factors such as binder chemical reaction, curing temperature/period, molarity of the solution, and rate of polymerization. The curing temperature helps in deciding the properties of geopolymer. Performance variables for geopolymer concrete such as selection of alkaline binder with pozzolana (Fly ash, slag, silica fume etc.) and interrelationship of GPC, reinforcing agent in geopolymer concrete with components responsible for durability are summarized in detail. The durability of concrete is reviewed with structure with shrinkage-resistant, resistant to sulfate attack, and consequences of carbonation. The various consequences of corrosion are also summarized in last of present review paper. Different research findings in this paper proves successfully that geopolymer is better construction material as compare to cement-based concrete

Influence of industrial by-products on the behavior of geopolymer concrete forsustainable development

Carbon dioxide emission in cement industries is a great concern for environment, which is increasing day by day.Therefore, it is very essential to find a possible material that can be used as a replacement of cement. Geopolymer concreteis a kind of inorganic concrete elucidating the formal usage of industrial and natural waste in either single or combinedform. Geopolymers are amorphous covalently bonded by a 3D network of inorganic molecules of aluminosilicate material.The formation of geopolymer concrete is greatly influenced by several factors such as binder chemical reaction, curingtemperature/period, molarity of the solution, and rate of polymerization. The curing temperature helps in deciding theproperties of geopolymer. Performance variables for geopolymer concrete such as selection of alkaline binder withpozzolana (Fly ash, slag, silica fume etc.) and interrelationship of GPC, reinforcing agent in geopolymer concrete withcomponents responsible for durability are summarized in detail. The durability of concrete is reviewed with structure withshrinkage-resistant, resistant to sulfate attack, and consequences of carbonation. The various consequences of corrosion arealso summarized in last of present review paper. Different research findings in this paper proves successfully thatgeopolymer is better construction material as compare to cement-based concrete

VIPP2 interacts with VIPP1 and HSP22E/F at chloroplast membranes and modulates a retrograde signal for HSP22E/F gene expression

VIPP proteins aid thylakoid biogenesis and membrane maintenance in cyanobacteria, algae, and plants. Some members of the Chlorophyceae contain two VIPP paralogs termed VIPP1 and VIPP2, which originate from an early gene duplication event during the evolution of green algae. VIPP2 is barely expressed under nonstress conditions but accumulates in cells exposed to high light intensities or H2O2, during recovery from heat stress, and in mutants with defective integration (alb3.1) or translocation (secA) of thylakoid membrane proteins. Recombinant VIPP2 forms rod-like structures in vitro and shows a strong affinity for phosphatidylinositol phosphate. Under stress conditions, >70% of VIPP2 is present in membrane fractions and localizes to chloroplast membranes. A vipp2 knock-out mutant displays no growth phenotypes and no defects in the biogenesis or repair of photosystem II. However, after exposure to high light intensities, the vipp2 mutant accumulates less HSP22E/F and more LHCSR3 protein and transcript. This suggests that VIPP2 modulates a retrograde signal for the expression of nuclear genes HSP22E/F and LHCSR3. Immunoprecipitation of VIPP2 from solubilized cells and membrane-enriched fractions revealed major interactions with VIPP1 and minor interactions with HSP22E/F. Our data support a distinct role of VIPP2 in sensing and coping with chloroplast membrane stress

Structural basis for VIPP1 oligomerization and maintenance of thylakoid membrane integrity

Vesicle-inducing protein in plastids 1 (VIPP1) is essential for the biogenesis and maintenance of thylakoid membranes, which transform light into life. However, it is unknown how VIPP1 performs its vital membrane-remodeling functions. Here, we use cryo-electron microscopy to determine structures of cyanobacterial VIPP1 rings, revealing how VIPP1 monomers flex and interweave to form basket-like assemblies of different symmetries. Three VIPP1 monomers together coordinate a non-canonical nucleotide binding pocket on one end of the ring. Inside the ring's lumen, amphipathic helices from each monomer align to form large hydrophobic columns, enabling VIPP1 to bind and curve membranes. In vivo mutations in these hydrophobic surfaces cause extreme thylakoid swelling under high light, indicating an essential role of VIPP1 lipid binding in resisting stress-induced damage. Using cryo-correlative light and electron microscopy (cryo-CLEM), we observe oligomeric VIPP1 coats encapsulating membrane tubules within the Chlamydomonas chloroplast. Our work provides a structural foundation for understanding how VIPP1 directs thylakoid biogenesis and maintenance

Adipocyte-derived extracellular vesicles increase insulin secretion through transport of insulinotropic protein cargo

Adipocyte-derived extracellular vesicles (AdEVs) are membranous nanoparticles that convey communication from adipose tissue to other organs. Here, to delineate their role as messengers with glucoregulatory nature, we paired fluorescence AdEV-tracing and SILAC-labeling with (phospho)proteomics, and revealed that AdEVs transfer functional insulinotropic protein cargo into pancreatic β-cells. Upon transfer, AdEV proteins were subjects for phosphorylation, augmented insulinotropic GPCR/cAMP/PKA signaling by increasing total protein abundances and phosphosite dynamics, and ultimately enhanced 1st-phase glucose-stimulated insulin secretion (GSIS) in murine islets. Notably, insulinotropic effects were restricted to AdEVs isolated from obese and insulin resistant, but not lean mice, which was consistent with differential protein loads and AdEV luminal morphologies. Likewise, in vivo pre-treatment with AdEVs from obese but not lean mice amplified insulin secretion and glucose tolerance in mice. This data suggests that secreted AdEVs can inform pancreatic β-cells about insulin resistance in adipose tissue in order to amplify GSIS in times of increased insulin demand

Toxicity of the Herbicide Atrazine: Effects on Lipid Peroxidation and Activities of Antioxidant Enzymes in the Freshwater Fish Channa Punctatus (Bloch)

The present study was undertaken to evaluate the toxicity and effects of a commercial formulation of the herbicide atrazine (Rasayanzine) on lipid peroxidation and antioxidant enzyme system in the freshwater air breathing fish Channa punctatus. The 12, 24, 48, 72 and 96 h LC50 of atrazine, calculated by probit analysis, were determined to be 77.091, 64.053, 49.100, 44.412 and 42.381 mg·L−1, respectively, in a semi static system with significant difference (p < 0.05) in LC10–90 values obtained for different times of exposure. In addition to concentration and time dependent decrease in mortality rate, stress signs in the form of behavioral changes were also observed in response to the test chemical. In fish exposed for 15 days to different sublethal concentrations of the herbicide (1/4 LC50 = ∼10.600 mg·L−1, 1/8 LC50 = ∼5.300 mg·L−1 and 1/10 LC50 = ∼4.238 mg·L−1) induction of oxidative stress in the liver was evidence by increased lipid peroxidation levels. The antioxidants superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) responded positively in a concentration dependent pattern, thus, suggesting the use of these antioxidants as potential biomarkers of toxicity associated with contaminations exposure in freshwater fishes

Genomes of trombidid mites reveal novel predicted allergens and laterally-transferred genes associated with secondary metabolism

Trombidid mites have a unique lifecycle in which only the larval stage is ectoparasitic. In the superfamily Trombiculoidea (“chiggers”), the larvae feed preferentially on vertebrates, including humans. Species in the genus Leptotrombidium are vectors of a potentially fatal bacterial infection, scrub typhus, which affects 1 million people annually. Moreover, chiggers can cause pruritic dermatitis (trombiculiasis) in humans and domesticated animals. In the Trombidioidea (velvet mites), the larvae feed on other arthropods and are potential biological control agents for agricultural pests. Here, we present the first trombidid mites genomes, obtained both for a chigger, Leptotrombidium deliense, and for a velvet mite, Dinothrombium tinctorium

Kryo-EM-Studien des Vesikel-induzierenden Protein in Plastiden

Vesicle Inducing Protein in Plastids (Vipp1) is one of the essential proteins for thylakoid biogenesis in both chloroplasts and cyanobacteria. However, the molecular structure and the exact function of Vipp1 is not yet known. Using cryo-electron tomography and sub-tomogram averaging, we showed that CrVipp1 rods can engulf liposome membranes containing phosphatidylinositol-4-phosphate (PI4P). Using single-particle cryo-electron microscopy, we solved the molecular structure of SynVipp1. We found that SynVipp1 predominantly assembled into barrel-like rings.Das Vesikel-induzierende Protein in Plastiden (Vipp1) ist sowohl in Chloroplasten als auch in Cyanobakterien eines der wichtigsten Proteine für die Thylakoidbiogenese. Jedoch sind Molekularstruktur und die genaue Funktion von Vipp1 bisher unbekannt. Mit Hilfe der Kryoelektronentomografie und der Untertomogrammittelung zeigten wir, dass CrVipp1 Liposomen umschließt, deren Membranen Phosphatidylinositol-4-phosphate (PI4P) enthalten. Mit der Einzelpartikelanalyse lösten wir die Molekularstruktur von SynVipp1, das bevorzugt in fassförmige Ringe assembliert

Cutaneous zygomycosis: A possible postoperative complication in immunocompetent individuals

Fungi in the class of zygomycetes usually produce serious infections in diabetics and immunocompromised hosts. Cutaneous zygomycosis is a less common form, with an unpredictable extent of anatomical involvement and clinical course. Here, we report two cases of primary cutaneous zygomycosis as postoperative complications in otherwise healthy females. Zygomycosis was suspected and specimens from the surgical debridement were examined by microbiological and histopathological studies for confirming the clinical diagnosis. Rapid diagnosis, liposomal amphotericin B, and proper debridement of affected tissue are necessary to avoid a fatal outcome