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The report presents the fabrication and application of a highly versatile, magnetic and robust iridium based photoredox nanocatalyst. Herein, Ir(PPy)3 based photocatalyst sites have been chemically engineered over the magnetic nanoparticles to encompass the captivating features of homogeneous iridium photocatalyst with the magnetically recyclable core. A household photoreactor was designed and fabricated to achieve highly selective visible light driven oxidative C-H arylation and C-H cyanation under sustainable and ambient reaction conditions utilizing the Ir@PyBz@ASMNPs photoredox nanocatalyst. The environment friendly Ir@PyBz@ASMNPs shows excellent photocatalytic activity, broad substrate adaptability and outstanding recyclability compared to the analogous homogeneous catalysts. Indeed, the Ir@PyBz@ASMNPs possess some key features including high surface area, high iridium metal loading and excellent stability. This work is expected to enlighten and provide new insights in the rational design of high performance and recoverable photoredox nanocatalyst through surface engineering strategy.

The Fe3O4-functionalized graphene oxide (Fe3O4@GO-SO3H) and waterborne epoxy (WEP) nanocomposites (WEP/Fe3O4@GO-SO3H) were fabricated via co-precipitation followed by sulfonation, and the effects of modified GO on mechanical behaviors of the WEP nanocomposites were further examined. The synthesized Fe3O4@GO-SO3H hybrid was analyzed and confirmed by FTIR, Raman, XRD, and TGA. It was convinced from the FESEM and the related analyses that the covalent functionalization of graphene oxide with Fe3O4 nanoparticles followed by sulfonation with 3-mercaptopropyl trimethoxysilane was encouraging to equal distribution in the WEP system. Meanwhile, the tight mutual sharing interfaces amid WEP and Fe3O4@GO-SO3H promote the stress transfer. As the content of Fe3O4@GO-SO3H increases, the tensile strength of WEP increases, but the totaling more than 0.2 wt% Fe3O4@GO-SO3H yields unfavorable results. When the filler content of Fe3O4@GO-SO3H arises to 0.2 wt%, the tensile strength of the nanocomposites was found to be 257% higher than that of the blank group. Besides, the DMA shows that the storage modulus and tanδ of the WEP/Fe3O4@GO-SO3H was remarkably enhanced due to the strong interactions between Fe3O4@GO-SO3H and WEP. The improved thermal stability and conductivity of the WEP nanocomposites was also achieved. It could be concluded that the appropriate quantity of Fe3O4@GO-SO3H toting up can significantly improve the mechanical properties of WEP/Fe3O4@GO-SO3H nanocomposites.

Ni, Cu and Cu–Ni nanostructures have been fabricated and homogeneously embedded on ultrathin two-dimensional (2D) carbon nitride (g-C3N4), and the surface morphology and composition of the resulting hybrid nanostructures were studied by XRD, TEM, HRTEM-elemental mapping, Raman spectroscopy and XPS. The new hierarchical hetero-structures dropcasted on GC anodes have been visualised by SEM and their catalytic performance have been examined in methanol electrooxidation reaction (MOR) under alkaline conditions. Nanosized Ni particles dispersed finely over g-C3N4 are very active electrocatalysts with MOR onset at potential 0.35 V and charge transfer resistance 0.12 kΩ. The stability of modyfied GC electrodes, examined under chronoamperometric conditions showed that for electrode loading with 4% (wt. %) of NiO the stable current density ca. 36 A g−1 (12 A cm2) was obtained during whole experiment (up to 160 min). For all catalyst studied the curent density obtained during MOR reaction was enhanced when electrode was iluminated by UV light λ∼400 nm, and the highest value were obtained for 4% Ni/CN catalyst ca. 127 A g−1 (22 A cm2). The Cu incorporation in the hybrid material evoke loss of activity mostly due to Cu+ irreversible reduction/oxidation to Cu° and Cu2+, CuO segregation and influencing electron transfer process which results in the increasing in the redox potential. These results represent an important step towards light-enhanced electro-reactive systems and sensors in which heterojunction formation can facilitate electron-hole separation and enable more efficient energy transfer.

Waterborne polyurethane (WPU) has been broadly used as adhesive and coating materials in many applications. In this work, the graphene oxide-silica (GOSI) nanocomposites, used as nanofillers in the WPU matrix, were produced by functionalizing graphene oxide with epoxy groups and nanosilica with amine groups using silane terminated coupling agents. The nanocomposite surface structures were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The polymer nanocomposite films show the excellent improvement in the mechanical and thermal properties. In the fractured surface study of the composite films by SEM, it was observed that the agglomeration of GO appears while the GOSI is uniformly distributed in the WPU matrix. Furthermore, the WPU/GOSI have regained the maximum tensile strength properties after two weeks of hydrolysis. The GOSI nanocomposites have enhanced interfacial crosslinking with the WPU matrix which is the prime reason for such development in the mechanical properties. The screen printing method was illustrated to cast the thin and transparent layer WPU nanocomposites on the leather surfaces. The WPU/GOSI coatings exhibit outstanding tear resistance, surface adhesiveness, and abrasion resistance properties. This approach of using GOSI composites as nanofiller in the polymer matrix may pave a novel path for surface coating strategies.

The current and estimated energy demand and their potential sources of supply indicate a daunting future for humanity on the planet unless sustainable solutions are developed. The scarcity, high cost and the potential environmental and health concerns related to widely used noble-metals make the situation even worse. Thus, active participation from scientific and industrial communities is essential to replace noble-metal (or any metal) based processes with more sustainable alternatives. In that context, recent developments in heteroatom-doped (especially nitrogen) nanocarbons and their wide-ranging applications show promises towards substituting the processes, which normally utilize expensive, scarce and hazardous materials. Herein, a brief overview of nitrogen-doped nanocarbons (NNCs) is provided highlighting their significance and sustainable prospects.

MK2 (p38MAPK-activated protein kinase 2) is essential for tumor necrosis factor (TNF) biosynthesis, mainly operating by post-transcriptional regulation. Deletion of the gene encoding MK2 strongly reduced serum TNF and protected against endotoxic shock, demonstrating the positive role of p38MAPK/MK2 in TNF signaling at the level of ligand expression. Recent evidence indicates that MK2 directly phosphorylates the TNF receptor interactor RIPK1 and suppresses its activity, thereby limiting TNF-mediated apoptosis and necroptosis – pointing to a more complex, double-edged role of MK2 in TNF signaling. In addition, novel MK2 substrates have emerged in the DNA damage response, autophagy, and obesity, making MK2 a multifunctional kinase at the crossroads of stress response and cell death. We therefore propose a more general role of p38MAPK/MK2 signaling in the timely coordinated onset and resolution of inflammation and beyond.

Measures of temperament have been previously related to gain and intake in beef cattle. Intake effects may be partially mediated through social interactions in that some temperament measures may directly relate to social dominance behavior. To examine the relationships between temperament, growth, and social dominance behavior, thirty-two crossbred steers were used in a 56-d randomized complete block design experiment with a 2 × 2 factorial treatment structure. Temperament treatments (assigned on d −7) were chute exit velocity (EV; slow vs. fast) and objective chute score (OCS; low vs. high), a novel temperament measure, defined as the coefficient of variation of recorded weight values collected at five Hz for 10 s while an animal’s head was restrained in a chute. Electronic ear tags with accelerometers were used to continuously measure animal activity. Social dominance behaviors were quantified using video records of 2 h intervals directly following feeding for d 1–13. Dominance was calculated as average dominance index and David’s score. Jugular blood samples were collected to analyze antibody response to leptospirosis vaccines. There were no EV by OCS interactions (P ≥ 0.23) for average daily gain (ADG) or antibody titers. High OCS steers gained 0.26 kg/d more than low OCS steers (P

Triple-negative breast cancer is an aggressive form of breast cancer with few therapeutic options if it recurs after adjuvant chemotherapy. RNA interference could be an alternative therapy for metastatic breast cancer, where small interfering RNA (siRNA) can silence the expression of aberrant genes critical for growth and migration of malignant cells. Here, we formulated a siRNA delivery system using lipid-substituted polyethylenimine (PEI) and hyaluronic acid (HA), and characterized the size, ζ-potential and cellular uptake of the nanoparticulate delivery system. Higher cellular uptake of siRNA by the tailored PEI/HA formulation suggested better interaction of complexes with breast cancer cells due to improved physicochemical characteristics of carrier and HA-binding CD44 receptors. The siRNAs against specific phosphatases that inhibited migration of MDA-MB-231 cells were then identified using library screen against 267 protein-tyrosine phosphatases, and siRNAs to inhibit cell migration were further validated. We then assessed the combinational delivery of a siRNA against CDC20 to decrease cell growth and a siRNA against several phosphatases shown to decrease migration of breast cancer cells. Combinational siRNA therapy against CDC20 and identified phosphatases PPP1R7, PTPN1, PTPN22, LHPP, PPP1R12A and DUPD1 successfully inhibited cell growth and migration, respectively, without interfering the functional effect of the co-delivered siRNA. The identified phosphatases could serve as potential targets to inhibit migration of highly aggressive metastatic breast cancer cells. Combinational siRNA delivery against cell cycle and phosphatases could be a promising strategy to inhibit both growth and migration of metastatic breast cancer cells, and potentially other types of metastatic cancer. Statement of Significance The manuscript investigated the efficacy of a tailored polymeric siRNA delivery system formulation as well as combinational siRNA therapy in metastatic breast cancer cells to inhibit malignant cell growth and migration. The siRNA delivery was undertaken by non-viral means with PEI/HA. We identified six phosphatases that could be critical targets to inhibit migration of highly aggressive metastatic breast cancer cells. We further report on specifically targeting cell cycle and phosphatase proteins to decrease both malignant cell growth and migration simultaneously. Clinical gene therapy against metastatic breast cancer with effective and safe delivery systems is urgently needed to realize the potential of molecular medicine in this deadly disease and our studies in this manuscript is intended to facilitate this endeavor.

A conventional plasmonic Ag-AgCl photocatalyst consists of Ag nanoparticles (AgNPs) and AgCl. Here, we converted a small amount of Ag+ on the surfaces of AgCl particles into single-atom Ag(0) (SAAg). SAAg was characterized with high-angle annular dark field aberration corrected (HAADF AC)-STEM and quantified with electron spin resonance (ESR). The obtained AgEG/Mg(OH)2 material was efficient and afforded excellent selectivity control between hydrodehalogenation and deiodination-borylation under visible light irradiation. SAAg acted as the 1e−-reducing site of the photocatalyst and its loading is linearly correlated with the initial reaction rate. While the quantity of SAAg was only 6.0 × 10–8 mol g−1, the TOF of SAAg reached 1.4 × 104 h−1. The oxidation state of SAAg retained 0 in both the resting and the working states. This study suggests SAAg may be an effective cocatalyst in general for reductive dehalogenation of organic halides.

The knowledge on thermo-kinetics, synergistic effect, and reaction mechanism of pyrolysis/co-pyrolysis of biomass with plastics is crucial for designing efficient reactor system and subsequently the pyrolysis/co-pyrolysis process. The present work explores thermal response, kinetics, reaction mechanism and thermodynamic analysis of pyrolysis and co-pyrolysis of individual corn cob (CC) and polyethylene (PE), and their blend in the ratio of 3:1 (w/w). Thermogravimetric analysis (TGA) data was obtained under inert atmosphere at various heating rates of 10, 20, and 30 °C/min and synergistic effect in the co-pyrolysis of CC and PE is discussed. The obtained TGA data was processed using various model-free isoconversional methods like KAS, FWO, Friedman, Starink, and Vyazovkin for determination of kinetics of pyrolysis/co-pyrolysis process of CC and PE. Average activation energy for CC pyrolysis was estimated to be 240 ± 51.25 kJ/mol, 240 ± 51.51 kJ/mol, 237 ± 49.67 kJ/mol, and 245 ± 52.10 kJ/mol according to KAS, Starink, FWO, and Vyazovkin models, respectively. Statistical analysis showed that the variation in reported values of activation energy was not significantly different (p = 0.994). Similar statistically insignificant difference was also observed for pyrolysis of PE and co-pyrolysis of CC and PE. Results showed that co-pyrolysis (CC + PE) requires 10% less activation energy than pyrolysis of CC alone. For the co-pyrolysis process, the extent of synergistic effect was discussed by difference in mass loss (ΔW). Investigation also revealed that residue left for co-pyrolysis of CC and PE is 50% less than pyrolysis of CC alone showing synergistic effect during co-pyrolysis. Thermodynamic parameters were calculated to illustrate complex mechanism of the process. Third order reaction, 3D diffusion Jander, and Ginstling–Brounshtein (D4) models were found to be best fitted for CC pyrolysis, PE pyrolysis, and co-pyrolysis, respectively. Results obtained are expected to be useful in the design of corn cob and waste polyethylene co-pyrolysis systems.

We present the first bottom-up approach to synthesize Fe(III)-functionalized carbon dots (CDs) from molecular precursors without the need of conventional thermal or microwave treatment and additional reagents. Specifically, sonication of xylene in the presence of anhydrous FeCl 3 results in oxidative coupling of the aromatic substrate towards Fe(III)-functionalized CDs. The as-prepared CDs are spherical in shape with a size of 3–8 nm, highly dispersible in organic solvents and display wavelength-dependent photoluminescence (PL). The iron ions attached to the surface endow the CDs with superior catalytic activity for olefin hydrogenation with excellent conversion and selectivity (up to 100%). The Fe(III)-CDs are more effective in the hydrogenation of a series of electron donating or withdrawing olefin substrates compared to conventional homogeneous or heterogeneous Fe(III)-based catalysts. The as-prepared heterogeneous nanocatalyst can be used repeatedly without any loss of catalytic activity. Importantly, the stability of the new catalysts can be easily monitored by PL intensity or quantum yield measurements, which certainly opens the doors for real time monitoring in a range of applications. Additionally, to the best of our knowledge, for the first time, the oxidative property of Fe-CDs was also explored in decomposition of hydrogen peroxide in water with the first order rate constant of 0.7 × 10 −2 min −1 , proving the versatile catalytic properties of such hybrid systems.

Engineered nanocages have emerged at the forefront of nanomaterial investigation as they possess tremendous potential to boost key chemical processes owing to their hollow architectures that can help in achieving high reactivity. With an intention to make profitable use of their morphological features guided chemical activity, we developed dispersable Co3O4 nanocages decorated with nickel nanoparticles for accessing a broad spectrum of pharmaceutically and biologically active N-heterocyclic quinoxaline nuclei using α-dicarbonyls and 1,2-diamines as precursor reagents. For designing Co3O4 nanocages, we employed a simple and scalable method involving Kirkendall effect in which thermal decomposition of Co3[Co(CN)6]2 was carried out thereafter, nanocages were loaded with Ni nanoparticles to obtain the final Ni@Co3O4 catalyst. Results revealed that Ni@Co3O4 catalyst possesses immense potential to accelerate condensation of diamines and di-carbonyls in absence of any additives under mild reaction conditions. The superior catalytic efficiency has been attributed to the hollow architecture of the nanocatalyst comprising of abundant catalytic sites. This protocol exhibits several remarkable attributes such as mild reaction conditions outstanding functional group tolerance, high yield, immense durability and reusability for six subsequent runs.

Gold nanoparticles (∼13 nm, 4 wt% Au) dispersed on reduced graphene oxide (Au/rGO) surface were prepared via the reduction of gold (III) chloride using sodium citrate on reduced graphene oxide support. The chemical, morphological, and size analyses of Au/rGO by XRD, XPS, TEM, HR-TEM/EDS, AAS, and Raman spectroscopy revealed that the hybrid material comprised of a well-defined rGO support decorated with gold nanoparticles. The ensuing catalyst was evaluated for the oxidation of ethyl benzenes (yields up to 95%) and oxidative esterification of aldehydes (73–97%) using oxygen as an environmentally friendly oxidant in good to excellent yields; reusable and recyclable catalyst displayed high activity without the use of toxic organic solvents.

Synthesis of novel C2-symmetric 1,2- 1,3- and 1,4- bis-sulfinamides and their use as effective ligands in rhodium (I) catalyzed asymmetric conjugate addition of arylboronic acids to cyclohexenone and cyclopentenones is described. C2-symmetry as well as chirality at the sulfur center in the ligand is crucial for the high enantioselectivity in the 1,4-addition reaction. It was also observed that the conjugate addition proceeded with good selectivity with Wilkinson's catalyst as the rhodium source.

Formal total synthesis of (+)-stemoamide is accomplished from 5-benzyloxypentanal. Key transformation in the synthesis is the conjugate addition of aza-allylanion obtained from allyl amine to an unsaturated ester.

It was studied a benign one-pot synthesis of a steam and SO2 stable molybdenum promoted cobalt catalyst supported on SBA-15 for CO oxidation runs at 730 C. The physicochemical properties of the catalyst were analyzed by XRD, SEM/HRTEM, UV–vis, Raman spectroscopy, XPS, H2-TPR, and NH3-TPD. Well-dispersed Co3O4 and, molybdenum species allowed to maintain CO conversion close to 90 % against 55 % over the non-Mo-promoted Co-catalyst. That promising behavior was attributed to the strong Co-Mo interaction that improved the acidic properties, which strongly decreased deactivation by SO2 and water steam. The impregnated catalyst presented formation of aggregated MoO3 species and Co3O4 mainly inside the SBA-15 mesopores, leading to lower CO oxidation activity and lower catalytic stability in the presence of the above interfering compounds. Thus, the one-pot prepared molybdenum promoted cobalt catalyst supported over mesoporous silica SBA-15 emerges as a potential alternative to substitute CO oxidation catalysts based on noble metals.

Total synthesis of (+)-γ-lycorane is accomplished from (S)-ethyl lactate. Key disconnections in the synthesis involve an iterative Claisen and Overman rearrangement reactions to install the chiral centers in the tetrahydroindole moiety while, Pictet-Spengler reaction is used for the synthesis of the isoquinoline unit.

The constant urge to boost the versatility of unsaturated polyester (UP) in the burgeoning area of automotive and aircraft industries has shifted the focus on developing high performance UP based nanocomposites with remarkable thermal, mechanical, and electrical properties. The current work traverses through the innovative method to contrive functionalized graphene oxide (f-GO)/UP nanocomposites. Graphene oxide, synthesized from graphite using modified Hummers’ method, manifests into f-GO (GO-MAH and GO-NH2) via surface chemical functionalization. Different loadings of f-GO were assimilated within UP matrix through in-situ polymerization. The comprehensive properties of the nanocomposites enhance, despite addition of f-GO as low as 0.04 wt%, which itself gives a scrupulous vindication of proper dispersion of fillers and formation of exfoliated and intercalated nanostructures, with SEM images furnishing the inference of meticulous dispersion. The fabricated nanocomposites exhibit tensile strength augmentation by 75.2% for ultralow content of 0.08 wt% f-GO. Furthermore, the 0.10 wt% addition of f-GO within UP displays 53.8% increase in storage modulus and thermal decomposition temperature at 10% mass loss boosts by 70.3 °C, while the electrical conductivity surges by 109 S/m. The surface functionalized graphene oxide and their interaction with UP played a vital role in their property enhancement.