Highly sensitive biomolecular fluorescence detection using nanoscale ZnO platforms

Fluorescence detection is currently one of the most widely used methods in the areas of basic biological research, biotechnology, cellular imaging, medical testing, and drug discovery. Using model protein and nucleic acid systems, we demonstrate that engineered nanoscale zinc oxide structures can significantly enhance the detection capability of biomolecular fluorescence. Without any chemical or biological amplification processes, nanoscale zinc oxide platforms enabled increased fluorescence detection of these biomolecules when compared to other commonly used substrates such as glass, quartz, polymer, and silicon. The use of zinc oxide nanorods as fluorescence enhancing substrates in our biomolecular detection permitted sub-picomolar and attomolar detection sensitivity of proteins and DNA, respectively, when using a conventional fluorescence microscope. This ultrasensitive detection was due to the presence of ZnO nanomaterials which contributed greatly to the increased signal-to-noise ratio of biomolecular fluorescence. We also demonstrate the easy integration potential of zinc oxide nanorods into periodically patterned nanoplatforms which, in turn, will promote the assembly and fabrication of these materials into multiplexed, high-throughput, optical sensor arrays. These zinc oxide nanoplatforms will be extremely beneficial in accomplishing highly sensitive and specific detection of biological samples involving nucleic acids, proteins and cells, particularly under detection environments involving extremely small sample volumes of ultratrace-level concentrations.     

Sedimentation of a circular disk in power law fluids

The continuity and momentum equations have been solved numerically for the two-dimensional steady flow of power law fluids over a thin circular disk oriented normal to the direction of flow. Extensive results on the individual and total drag coefficients are obtained as functions of the power law flow behavior index (0.4 < or = n < or = 1.0), Reynolds number (1 < or = Re < or = 100) and the blockage ratio, disk-to-cylinder diameter ratio (0.02 < or = e < or = 0.5), which can be used to estimate the settling velocity of a circular disk. The numerical predictions of drag are consistent with the scant experimental results available in the literature.     

Study of the formation of perovskite type lanthanum ruthenates by heating their hydrous precursor

Emanation thermal analysis (ETA), differential thermal analysis (DTA), thermogravimetry (TG), evolved gas analysis with mass spectrometric detection (EGA-MS), and X-ray diffraction (XRD) were used to investigate the formation of perovskite type lanthanum ruthenates on heating their hydroxide precursor in argon from 20 to 1200 degrees C. The co-precipitated lanthanum-ruthenium mixed hydroxide containing a small amount of carbonates was used as a precursor. The mass loss corresponding to the release of water and CO(2) from the precursor was determined by TG and EGA (MS), respectively. The ETA characterized the exposure of sample surface after release of water and CO(2), as well as microstructure development corresponding to the crystallization and structure ordering of LaRuO(3) and La(3.5)Ru(4.0)O(13) perovskite phases. The obtained information on formation of phases and their transformation is useful for optimizing their synthesis protocols for achieving the desired physical properties, and to estimate the thermal stability of these materials to be used as catalysts.     

Ultrasensitive polyaniline-nickel oxide cladding modified with urease immobilized intrinsic optical fiber urea biosensor

Herein, we report a polyaniline-nickel oxide (PANI-NiO) nanocomposite as an efficient immobilization matrix for development the optical fiber urea biosensor. Optical fiber sensing probe was developed by removing some portion of optical fiber at middle and modified with PANI-NiO matrix. After the modification of cladding removed portion, it was immobilized with enzyme urease via glutaraldehyde as a bi-functional cross-linking agent. The physicochemical and optical properties of the PANI-NiO matrix were explored by X-ray diffraction, scanning electron microscopy, ultraviolet–visible, and Fourier transform infrared spectroscopic techniques. The characteristic features and performance of the developed sensor were evaluated via recording the output power and modal power distribution by means of a charge-coupled device camera. The developed urea biosensor exhibits a selective response towards urea concentrations in the linear range 1 nM–100 mM with a lower detection limit of 1 nM. Sensor recorded as a 40 days stability and response time ~1 min. Thus, the obtained experimental results of the developed sensor promote its applicability with practical prospects in diverse field.     

Kinetics of hydroformylation of camphene using rhodium-phosphite catalyst

Kinetics of hydroformylation of camphene was investigated in the presence of [Rh(CO)₂(acac)]/P(OPh)₃ catalyst in a temperature range of 363–383 K. The influence of parameters such as stirring speed, camphene, catalyst, ligand concentrations, and partial pressures of H₂ and CO on the activity and selectivity of the catalyst has been studied. The rate showed a first-order dependence with respect to catalyst and camphene concentrations. The effect of partial pressure of hydrogen showed fractional order dependence. The plots of rate versus excess ligand, that is, (P(OPh)₃) concentration and rate versus CO partial pressure passed through maxima and showed typical substrate/ligand inhibited kinetics. An empirical rate equation has been proposed and found to be in good agreement with the observed rate data. The kinetic parameters and activation energy were also evaluated.     

Discovery of a Novel Mycobacterial F-ATP Synthase Inhibitor and its Potency in Combination with Diarylquinolines

The F₁F_O-ATP synthase is required for growth and viability of Mycobacterium tuberculosis and is a validated clinical target. A mycobacterium-specific loop of the enzyme's rotary γ subunit plays a role in the coupling of ATP synthesis within the enzyme complex. We report the discovery of a novel antimycobacterial, termed GaMF1, that targets this γ subunit loop. Biochemical and NMR studies show that GaMF1 inhibits ATP synthase activity by binding to the loop. GaMF1 is bactericidal and is active against multidrug- as well as bedaquiline-resistant strains. Chemistry efforts on the scaffold revealed a dynamic structure activity relationship and delivered analogues with nanomolar potencies. Combining GaMF1 with bedaquiline or novel diarylquinoline analogues showed potentiation without inducing genotoxicity or phenotypic changes in a human embryonic stem cell reporter assay. These results suggest that GaMF1 presents an attractive lead for the discovery of a novel class of anti-tuberculosis F-ATP synthase inhibitors.     

Recent Advances and Developments of in vitro Evaluation of Heterocyclic Moieties on Cancer Cell Lines

Besides worthy development in cancer therapy, cancer is still one of the leading causes of death, worldwide. The future burden of cancer will probably be even larger because people are adopting poor lifestyles with poor diet, frequently smoking and less physical activity. The effective anticancer drugs having efficacy and selectivity with low toxicity is still a challenge for the scientific fraternity. The advances in the cancer study have its origin on the availability of different types of experimental model systems that review the various forms of this disease. Cell lines emerge as a feasible alternative for anticancer activities, being at the same time easy to manipulate and molecularly characterize. Heterocycles are key structural components of many of the anti‐cancer drugs available on the market today. Indeed, of the novel molecular anti‐cancer agents approved by the FDA between 2010 and 2017, almost two‐thirds contained heterocyclic rings within their structures. This review summarizes and provides updated literature on heterocyclic compounds using various cancer cell lines reported during the period of 2014–2017 together with the structure‐activity relationships.     

Monitoring and Accelerating Methods of Corrosion for Reinforced Concrete: A Review

Corrosion is the irreversible, interfacial reaction of metals in the presence of an electrochemical environment which ultimately results in the deterioration of metals. Corrosion of reinforcement is the major problem in the reinforced concrete (RC) structure. Corrosion of reinforcement is a slow process because of the protective layer of concrete. Even in a severely corrosive environment corrosion process takes time to be initiated and propagated. Since to carry out research work, some techniques are required to accelerate the corrosion process in the shortest period. To overcome this problem, in the past, many researchers use a different method to accelerate the corrosion of steel in concrete. In this paper, a review is presented of various techniques used for accelerated corrosion testing. The suitability of reviewed methods on corrosion acceleration for several research works is presented. After that few case studies review to make use of various predicted empirical models and an experimental technique for predicting corrosion rate and the assessment of the remaining life of the structure. And finally, the paper is concluded by comparing the natural method of corrosion and the accelerated method of corrosion and the future scope of accelerated corrosion.     

Evaluating Properties of Green Concrete Produced Using Waste Marble Powder,Quarry Dust,and Paper Pulp

Industrial waste locks are used as raw materials to reduce harmful effects on the environment and improve environmental performance. Marble clay powder can be used as a filling aid and can fill voids in concrete structures. This article will show you how to use a maximum natural sand alternative in concrete with marble powder and quarry dust. The challenge of the 21st century is to change to a new form that can support the natural system. This necessitates a radical rethinking of how to give the community infrastructure and housing. Making a concerted effort to develop novel, innovative, and alternative construction materials may be necessary. Jungles of concrete around cause's impact on the Environment and it would result in climate change. Mankind must avoid the use of things that are detrimental to the environment. So in this paper, it is decided to address the issue by adopting the use of the green concrete concept which is environmentally friendly. Green concrete is concrete made up using industrial wastes such as marble powder, quarry dust, wood ash, paper pulp, etc. Green concrete, which is capable of sustainable development, helps to reduce the consumption of natural resources, energy use, and environmental pollution. Green concrete is more cost-effective than ordinary concrete and reduces the cost of resultant concrete by 14%–20%. It is also observed that the alkali-aggregate reaction and sulfate attack resistance of concrete are both significantly improved. Green concrete is a useful tool for lowering environmental pollution and enhancing concrete's resistance to harsh conditions. All stages of infrastructure construction and rehabilitation will follow this trend of using new cement and techniques. Green concrete's adaptability and its performance derivatives will meet a variety of future needs.