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De novo initiation by viral RNA-dependent RNA polymerases often requires a polymerase priming residue, located within a priming loop, to stabilize the initiating NTPs. Polymerase structures from three different non-segmented negative strand RNA virus (nsNSV) families revealed putative priming loops in different conformations, and an aromatic priming residue has been identified in the rhabdovirus polymerase. In a previous study of the respiratory syncytial virus (RSV) polymerase, we found that Tyr1276, the L protein aromatic amino acid residue that most closely aligns with the rhabdovirus priming residue, is not required for RNA synthesis but two nearby residues, Pro1261 and Trp1262, were required. In this study, we examined the roles of Pro1261 and Trp1262 in RNA synthesis initiation. Biochemical studies showed that substitution of Pro1261 inhibited RNA synthesis initiation without inhibiting back-priming, indicating a defect in initiation. Biochemical and minigenome experiments showed that the initiation defect incurred by a P1261A substitution could be rescued by factors that would be expected to increase the stability of the initiation complex, specifically increased NTP concentration, manganese, and a more efficient promoter sequence. These findings indicate that Pro1261 of the RSV L protein plays a role in initiation, most likely in stabilizing the initiation complex. However, we found that substitution of the corresponding proline residue in a filovirus polymerase had no effect on RNA synthesis initiation or elongation. These results indicate that despite similarities between the nsNSV polymerases, there are differences in the features required for RNA synthesis initiation.

It is generally thought that the promoters of non-segmented, negative strand RNA viruses (nsNSVs) direct the polymerase to initiate RNA synthesis exclusively opposite the 3´ terminal nucleotide of the genome RNA by a de novo (primer independent) initiation mechanism. However, recent studies have revealed that there is diversity between different nsNSVs with pneumovirus promoters directing the polymerase to initiate at positions 1 and 3 of the genome, and ebolavirus polymerases being able to initiate at position 2 on the template. Studies with other RNA viruses have shown that polymerases that engage in de novo initiation opposite position 1 typically have structural features to stabilize the initiation complex and ensure efficient and accurate initiation. This raised the question of whether different nsNSV polymerases have evolved fundamentally different structural properties to facilitate initiation at different sites on their promoters. Here we examined the functional properties of polymerases of respiratory syncytial virus (RSV), a pneumovirus, human parainfluenza virus type 3 (PIV-3), a paramyxovirus, and Marburg virus (MARV), a filovirus, both on their cognate promoters and on promoters of other viruses. We found that in contrast to the RSV polymerase, which initiated at positions 1 and 3 of its promoter, the PIV-3 and MARV polymerases initiated exclusively at position 1 on their cognate promoters. However, all three polymerases could recognize and initiate from heterologous promoters, with the promoter sequence playing a key role in determining initiation site selection. In addition to examining de novo initiation, we also compared the ability of the RSV and PIV-3 polymerases to engage in back-priming, an activity in which the promoter template is folded into a secondary structure and nucleotides are added to the template 3´ end. This analysis showed that whereas the RSV polymerase was promiscuous in back-priming activity, the PIV-3 polymerase generated barely detectable levels of back-primed product, irrespective of promoter template sequence. Overall, this study shows that the polymerases from these three nsNSV families are fundamentally similar in their initiation properties, but have differences in their abilities to engage in back-priming.

Solar water splitting has attained much attention in recent years for renewable and clean production of hydrogen from water under irradiation by sunlight. Solar water splitting has been progressively at the forefront of chemical research and also provides a promising path for sustainable hydrogen production. TiO2 has a wide range of applications and is considered as one of the most propitious semiconductors due to its photo-stability, low price and chemical stability. TiO2 nanotubes have been prepared by using electrochemical anodization method followed by organic dye deposited onto the TiO2 nanotubes. rGO-supported TiO2 nanotubes and dye-doped graphene-supported TiO2 nanotubes show more efficient behavior for water splitting as compared to pure TiO2 nanotubes. The surface morphology, elemental composition, structure and size of the nanocrystalline TiO2 nanotubes and dye-doped graphene-supported TiO2 nanotubes were examined by using SEM, XRD, EDX and UV/Visible spectroscopy, respectively. Dye-doped graphene-supported TiO2 nanotubes have been utilized for efficient solar water splitting. [ABSTRACT FROM AUTHOR]

The acid base status of a dairy cow is maintained within a narrow range. The key mechanisms involving blood, cells and lungs, perform this function. Although other minerals have an impact on acid base metabolism, the minerals used in dietary cation-anion balance (DCAB) namely sodium (Na), potassium (K) and chloride (Cl) have the greatest effect. Hence, acid base status implicates other biological functions of dairy cows. Low DCAB prepartum reduces the incidence of milk fever and increases the productivity by simmering down the severity of hypocalcaemia. High DCAB diets have proved to increase dry mater and water intake and production and to mitigate the effects of heat stress.

This research paper deals with the modeling, analysis and simulation of a two degree of freedom pan tilt platform (PTP) for rapidly positioning a camera. The PT?, with 2-revolute joints, is a device that makes possible for the camera to point in a desired direction. The objective of this paper is to derive a mathematical model of the PTP to point in a desired direction. To achieve the objective, a feedback control system with PD controller was analyzed and simulated in section III. The PTP was used on unmanned aerial vehicle to perform visual tracking experiments for moving objects. There is a growing demand for control systems with motion tracking ability. The practicality of this project can be extended to a broad range of applications. Of these, the most apparent use is in defense, where there is a strong emphasis on reliably neutralizing threats without risking human life. Unmanned aerial systems can provide significant reductions in manpower and risk to humans for critical security and defense roles. The applications of PTP m defense and security applications have been increased significantly in recent years. Such applications include target acquisition, intelligence, surveillance and reconnaissance, border patrol, maritime security, search and rescue, and environmental monitoring. Also, several applications for this device exist both in law enforcement and in entertainment.

In this research work, the emphasis is on the study of the effects of friction in the revolute joint for fine manipulation of robotic arm manipulators. The friction model is used to capture the friction in static mode, the breakaway point of displacement and the linear part of the friction when asperity junctions arc broken. The experimental setup is designed to attain Coulomb and viscous friction parameters in the revolute joint with velocity sensor equipped with mechanical system. The velocity sensor detects velocity response as controlled ramp torque is applied to the physical model to evaluate friction in the joint. The physical model is designed and built in MSC ADAMS environment and simulated using the same parameters which were experienced by the real model. The block diagram is drawn in the Simulink: (MATLAB) under same configuration and then simulated. The results, obtained from MSC ADAMS and Simulink, are compared with the experimental data.

Automated synthesis refers to design of physical systems using any of the models proposed for machine intelligence like evolutionary computation, neural networks and fuzzy logic. Mechatronic systems arc mixed or hybrid systems as thcy combine elements from different cncrgy domains. These dynamic systems are inherently complex and capturing underlying energy behavior among interacting sub-systems is difficult owing to the variety in the composition of the mechatronic systems and also due to the limitation imposed by conventional modeling techniques unable to handle more than one energy domain. Bond-Graph modeling and simulation is an advanced domain independent, object oriented and polymorphic graphical description of physical systems. The universal modeling paradigm offered by Bond-Graphs is well suited for mcchatronic systems as it can represent their multi energy domain character using a unified notation scheme. Genetic programming is one of the most promising evolutionary computation techniques. The genetic programming paradigm is modeled on Darwinian concepts of evolution and natural selection. Genetic programming starts from a high level statement of a problem's requirements along with a fitness criterion and attempts to produce a computer program that provides a solution to the problem. Combining unified modeling and analysis tools offered by Bond-Graphs with topologically open ended synthesis and search capability of genetic programming, a novel automated design methodology has been developed for generating mechatronic systems designs using an integrated synthesis, analysis and feedback scheme which comes close to the definition of a true automated invention machine. This research paper is a brief introduction to all concepts associated with automated design of mechatronic systems using Bond-Graphs and genetic programming and explains the novel automated design methodology with a design example.

Composting with efficient microbes is considered a sustainable strategy for effective conversion of agricultural discards into a productive biofertilizer. The present study was designed to isolate fungal strain efficient in releasing hydrolytic enzymes for accelerated decomposition and value addition of press mud (PM). In order to tolerate higher temperatures and pH variations during composting, the analysis specifies the different enzymatic behavior at varied temperature and pH range and the strain was also tested for aflatoxins production to produce biofertilizer safe for crop application. The physicochemical characteristics of PM such as total organic carbon (TOC), C/N ratio, electrical conductivity (EC), cation exchange capacity (CEC), total Kjeldahl nitrogen (TKN), total phosphorus (TP), and total potassium (TK) during composting were also studied as compared to control. The results indicated that among seven fungal isolates, Aspergillus niger (A. niger) PM-4 was selected as the best enzyme producers by producing carboxymethyl cellulase (CMCase) α-Amylase, pectinase, and xylanase at a broader temperature and pH spectrum. Composting of PM with A. niger PM-4 leads to significant reduction in TOC (21.2%), C/N ratio (21.3%), increase in EC (25%), CEC (98%), TKN (10.5%), TP (9.2%), and TK (41%) compared to control with one month maturity duration. The A. niger PM-4 also inhibiting mycotoxin growth (aflatoxins) and its inoculation into PM generated mature biofertilizer with germination index (GI) 96.5% after a month representing a cheaper, effective and sustainable approach for waste utilization. [ABSTRACT FROM AUTHOR]

Spinel ferrites are attaining huge importance in the modern era, due to their incredible properties, which means they are widely used in various fields. Therefore, in this paper a cost-effective and environmentally friendly preparation of Mg0.25Ni0.25Cu0.5−xCoxFe1.97La0.03O4 (x = 0.0, 0.125, 0.25, 0.375, and 0.5) ferrites via the sol–gel auto-combustion method were carried out. How the structural and functional properties varied with the Cu to Co ratio was studied. It was found that the crystallite size (D) was reduced from 47.2 to 27.6 nm as the Co2+ increased from x = 0.0 to 0.5. While the two major absorption bands including the higher frequency band (υ1) and lower frequency band (υ2) lie in the range of 573.80–538.65 cm−1 and 470.37–405.65 cm−1 belong to the spinel matrix. Five active Raman modes were found in the range of wave number 200–800 cm−1 corresponds to the sublattices of the spinel structure. The optical bandgap increased from 0.85 eV to 1.33 eV for x = 0.0 to x = 0.25 and then observed optical band gap was 1.15 eV and 1.46 eV for x = 0.375 to x = 0.5. The resistivity (ρ) was minimum for Co2+ concentration x = 0.25 at low temperature, while at high temperature the resistivity (ρ) was maximum for Co2+ doping x = 0.25. The temperature coefficient of resistance percentage (TCR %) was −2.66%/K at 513 K for x = 0.25, as shown in the graphical abstract. At lower frequencies, the impedance was observed maximum for Co2+ doping x = 0.125 and minimum for x = 0.375. These findings indicate that the as-prepared ferrites are a potential candidate for optoelectrical and bolometric devices. Highlights: Mg0.25Ni0.25Cu0.5−xCoxFe1.97La0.03O4 synthesis via the sol-gel auto-combustion method. The crystallite size was decreased with Co2+ doping. At high temperatures, the resistivity (ρ) was maximum for Co2+ doping x = 0.25. At lower frequency, the impedance was maximum for Co2+ doping x = 0.125. The temperature coefficient of resistance percentage (TCR%) was −2.66%/K at 513 K for x = 0.25. [ABSTRACT FROM AUTHOR]

Fixed bed column studies were carried out to evaluate the performance of natural Ceiba pentandra (kapok) in removal of residual oil from palm oil mill effluent (POME) under varying flow rate and packing density. A multilevel factorial design based on chemical oxygen demand (COD) and turbidity of the effluent was developed. COD was significantly affected by the effects of flow rates. The maximum packing density and flow rate for maximum COD reduction were observed at 0.08 g/cm3and 5ml/min. COD reductions were observed more than 99% at all packing densities and flow rates. Turbidity reduction ranged from 92.9-95.8% at all packing densities and flow rates. Fixed bed column designed had been successfully achieved to remove residual oil from palm oil mill effluent (POME) under different packing densities and flow rates. The results suggest that kapok fiber can be used as a low-cost alternative for the removal of residual oil from palm oil mill effluent (POME). [ABSTRACT FROM AUTHOR]

To assess health risks due to heavy metals, it is essential to quantify them in the vegetables. Hence, this study was conducted to investigate heavy metals (Zn, Ca, and Mg) concentrations in different parts (roots, stems, leaves, and fruits) of tomato plant (Lycopersicon esculentum), sampled from three different locations of Multan district. The collected samples such as roots, leaves, stems, and fruits were oven dried at 110°C and 2 g of each sample was digested with 5 mL of concentrated nitric acid (Merck). These samples were then subjected for analysis of these metals using atomic absorption spectrometry (Hitachi Model A-1800). The results of this study revealed that the concentration of metals in L. esculentum increased in the order of Ca>Mg>Zn. By the comparison of all three metals accumulated in different parts of L. esculentum, we concluded that Ca and Mg are present in higher concentration with the exception of zinc which has rather low toxicity but a severe impact on human health. Results of our investigation show that HRI value for Zn is greater than 1 so it poses potential risks to human health. [ABSTRACT FROM AUTHOR]

A perfect electrically conducting (PEC) cylinder (having a circular cross-section) encapsulated with uniaxial anisotropic chiral medium was studied emphasizing the features of scattering. A conducting sheath helix structure having a varying orientation with respect to the optical axis (or pitch angle) was assumed to be at the outermost surface. This allows alterations in scattering patterns. The echo width of the structure was evaluated under the assumption of parallel polarized oblique incidence of waves. The effect on scattering was evaluated under varying chirality and permittivity of the coating medium along with the variations in the helix pitch angle. The obtained results are compared with those achieved by replacing the chiral coating with a simple anisotropic kind of medium (without chirality). [ABSTRACT FROM AUTHOR]

Byline: Imran S. Sarwar, Afzaal M. Malik The ability to identify and follow a moving object is not only important for human activities, but it is also critical necessity in the use of robots for automation and manufacturing, security applications and for life sciences. This can be achieved by using the two degree of freedom (2-DOF) robotic system with a camera. For this purpose, dynamical models of pan and tilt mechanisms were determined by using Newton-Euler equation. The stability analysis of dynamical models is performed before designing the motion controllers for the 2-DOF robotic system. To perform the analysis and simulation, all the parameters involved in the system dynamics were identified. The objective of this research work is to derive motion controllers for the pan and tilt mechanisms based on dynamical model. These controllers make possible for camera to point in a desired direction within allowable specifications.