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The effect of organic solvents on alkaline proteases was assessed for native, recombinant, and metagenomically derived alkaline proteases. Their stability and the effects of physicochemical parameters were studied in the presence of hexane. The native enzyme was comparatively more resistant against the organic solvents than the recombinant counterparts. On the other hand, the metagenomically derived alkaline protease was minimally resistant against solvents. A similar trend was apparent for the stability of enzyme in organic solvents. The novelty of this study lies in the fact that the majority of the studies on the solvent tolerance have focused on the mesophilic enzymes, while those from the haloalkaliphilic bacteria have received little attention. The comparative tolerance of the native, recombinant, and metagenomic alkaline proteases against the organic solvent has practical importance. The phylogenetic relatedness among the various protease sequences will be described.

Climate change has been considered among the greatest challenge to living organisms. Medicinal and aromatic plants are no exception to it. The practice of use of therapeutic plant has proved to be particularly important in the health system all over the world. WHO predicted that 60% of the earth population and 80% of the population of 3rd world countries bank on herbal medicine, for their wellbeing requirements. Environmental conditions under the influence of climate change is dreadful not only for declining the quality of planting material but also severely retards public health. Our main idea is to focus on cultivation of local valued plants, training for farmers, preservation of traditional knowledge, developing awareness among people regarding alarming influence of climate change on medicinal plants. Anthropogenic activity-mediated climate change has devastating impacts on species varieties, on the earth. The augmented releases of greenhouse gases in the air; mainly of CO2 is the main reason for climatic changes. Study reveals the true understanding of effect of changing climate scenario on Medicinal plants. Differential patterns of climate change cause abiotic stress and can change the growth physiology, growth pattern, declines in biomass production, changes in phytochemical active constituents and overall changes the quality and safety of medicinal plants.After studying enormous review papers, detailed information regarding repercussions of climate change on therapeutic plants is found to be so negligible as compared to other trade crops, therefore we have tried to highlight the discipline in a comprehensive manner.

A minimum quantity lubrication system using biodegradable cutting fluids has facilitated the excellent machining performance and is observed as more sustainable. In the view of enhancement of machining performance, the utilization of nanofluids with a minimum quantity lubrication system as a cutting fluid delivered noteworthy outcomes. For the present experimental investigation, the monotype nanofluids (copper oxide and zinc oxide) and a hybrid nanofluid (copper oxide/zinc oxide) were synthesized by using a two-step method. Scanning electron microscopy and energy dispersive X-ray analysis were performed to characterize the synthesized nanoparticles. A vegetable oil was utilized as a base fluid and three types of nanofluids were prepared by the addition of a surfactant (butenol). Also, ultrasonication has been performed to avoid the agglomeration of nanoparticles into the base fluid. The thermal conductivity evaluation of prepared nanofluids was carried out by using a hot wire method. The effects of three nanofluids were investigated by considering three machining input variables (cutting speed, feed rate and depth of cut) on response variables (surface roughness and cutting zone temperature) during bearing steel turning under nanofluid minimum quantity lubrication cooling conditions. The multi-objective optimization was performed by using grey relational analysis and found that the hybrid nanofluid (copper oxide/zinc oxide) was noted as the highly effective cooling condition as equated to copper oxide and zinc oxide monotype nanofluid. The hybrid nanofluid (copper oxide/zinc oxide) shows a 65% and 60% reduction in surface roughness on comparing with copper oxide and zinc oxide nanofluids, respectively. Also, the minimization of cutting zone temperature was observed under the hybrid nanofluid (copper oxide/zinc oxide) by 11% and 13% on equating with copper oxide and zinc oxide nanofluids, respectively.

Industry 4.0(I4.0) a German project can influence whole industrial and business system by digital transformation of product design, smart manufacturing and delivered to consumer. Industry 4.0(I4.0) project combines the physical world and digital world together through cyber physical systems and helps SMEs in enhancing production processes and increase productivity through emerging technologies such as Internet of Things and Services, Machine learning, Virtual Reality, cloud computing, business analytics etc. However, adoption and implementation of Industry 4.0 project is not an easy task due to existence of various challenges. In the present study, a survey is conducted with 40 Indian manufacturing and service organisations to get their opinion on Industry 4.0 and the level of adoption of in their organization. The objective of this research is to identify the general awareness and understanding of the concepts of Industry 4.0(I4.0) and its related emerging technologies along with their implementation levels in selected organizations. With the feedback received from the selected organizations, this paper analyzes the results and give some discussion.

Sedimentation in active fluids has come into focus due to the ubiquity of swimming micro-organisms in natural and industrial processes. Here, we investigate sedimentation dynamics of passive particles in a fluid as a function of bacteria E. coli concentration. Results show that the presence of swimming bacteria significantly reduces the speed of the sedimentation front even in the dilute regime, in which the sedimentation speed is expected to be independent of particle concentration. Furthermore, bacteria increase the dispersion of the passive particles, which determines the width of the sedimentation front. For short times, particle sedimentation speed has a linear dependence on bacterial concentration. Mean square displacement data shows, however, that bacterial activity decays over long experimental (sedimentation) times. An advection-diffusion equation coupled to bacteria population dynamics seems to capture concentration profiles relatively well. A single parameter, the ratio of single particle speed to the bacteria flow speed can be used to predict front sedimentation speed., Comment: Soft Matter, (2021). arXiv admin note: substantial text overlap with arXiv:1710.04068

Machining industries are moving towards sustainable production processes. Nanofluid assisted minimum quantity lubrication is the perfect combination in the field of ecological machining process. The objective of current investigation is to evaluate the influence of Cu nanofluid on bearing steel turning operation. L9 orthogonal array employed to perform the experimentation. The output parameters surface roughness and cutting zone temperature were selected. The cutting speed, feed rate and depth of cut are utilized as a machining input parameters. For multi-objective optimization, the grey relational analysis technique was performed to identify the optimum condition. Investigation resulted that Cu nanofluid with minimum quantity lubrication observed as the most significant cooling environment as compared to vegetable cutting fluid. The output parameters surface roughness and cutting zone temperature effectively reduced under Cu nanofluid MQL as compared to vegetable oil centered cutting fluid cooling environment.

Mucosal-associated invariant T (MAIT) cells are abundant innate-like T cells important in antimicrobial immunity. These cells express a semi-invariant T cell receptor that recognizes the Major Histocompatibility Complex (MHC) class I-related protein 1 (MR1) in complex with small metabolite antigens derived from a range of commensal and pathogenic bacteria and yeasts, but not other pathogens such as viruses. Thus, MR1 stimulation of MAIT cells was thought to act as a sensor of bacterial infection and was not directly involved in anti-viral immunity. Surprisingly, viruses have recently been shown to directly impair MR1 antigen presentation by targeting the intracellular pool of MR1 for degradation. In this review, we summarize our current understanding of viral evasion of MR1 presentation pathway, and contrast this to evasion of other related MHC molecules. We examine MAIT cell activity in viral infection with a focus on the role of TCR-mediated activation of these innate-like cells and speculate on the selective pressure for viral evasion of MR1 antigen presentation. Overall, viral evasion of MR1 presentation uncovers a new avenue of research and implies that the MR1-MAIT cell axis is more important in viral immunity than was previously appreciated.

We report the practical synthesis of a key fragment of islatravir (MK-8591), a novel nucleoside reverse transcriptase translocation inhibitor (NRTTI) currently under investigation for treatment and...

Advances in three-dimensional nanofabrication techniques have enabled the development of lightweight solids, such as hollow nanolattices, having record values of specific stiffness and strength, albeit at low production throughput. At the length scales of the structural elements of these solids-which are often tens of nanometers or smaller-forces required for elastic deformation can be comparable to adhesive forces, rendering the possibility to tailor bulk mechanical properties based on the relative balance of these forces. Herein, we study this interplay via the mechanics of ultralight ceramic-coated carbon nanotube (CNT) structures. We show that ceramic-CNT foams surpass other architected nanomaterials in density-normalized strength and that, when the structures are designed to minimize internal adhesive interactions between CNTs, more than 97% of the strain after compression beyond densification is recovered.

Burnishing is becoming a promising surface finishing process to enhance materials surface properties. The control of the various process parameters yields the desired surface characteristics in brass materials. In the current work, free machining brass specimens were burnished by Abrasive Assisted Burnishing(AAB) process and Plain Burnishing (PB) process using ball burnishing tool. Response Surface Methodology was used to design the experiments in which Burnishing Force, Speed, Feed and Number of Passes were chosen as the process parameters. The minimum surface roughness achieved by PB and AAB was 0.1451 µm and 0.1041 µm respectively. The maximum surface hardness achieved using PB and AAB on the brass specimen was 207 HV and 248 HV respectively. The ball burnishing of free machining brass by AAB resulted in better surface characteristics as compared to the PB process.

Blood clots form at the site of vascular injury to seal the wound and prevent bleeding. Clots are in tension as they perform their biological functions and withstand hydrodynamic forces of blood flow, vessel wall fluctuations, extravascular muscle contraction and other forces. There are several mechanisms that generate tension in a blood clot, of which the most well-known is the contraction/retraction caused by activated platelets. Here we show through experiments and modeling that clot tension is generated by the polymerization of fibrin. Our mathematical model is built on the hypothesis that the shape of fibrin monomers having two-fold symmetry and off-axis binding sites is ultimately the source of inherent tension in individual fibers and the clot. As the diameter of a fiber grows during polymerization the fibrin monomers must suffer axial twisting deformation so that they remain in register to form the half-staggered arrangement characteristic of fibrin protofibrils. This deformation results in a pre-strain that causes fiber and network tension. Our results for the pre-strain in single fibrin fibers is in agreement with experiments that measured it by cutting fibers and measuring their relaxed length. We connect the mechanics of a fiber to that of the network using the 8-chain model of polymer elasticity. By combining this with a continuum model of swellable elastomers we can compute the evolution of tension in a constrained fibrin gel. The temporal evolution and tensile stresses predicted by this model are in qualitative agreement with experimental measurements of the inherent tension of fibrin clots polymerized between two fixed rheometer plates. These experiments also revealed that increasing thrombin concentration leads to increasing internal tension in the fibrin network. Our model may be extended to account for other mechanisms that generate pre-strains in individual fibers and cause tension in three-dimensional proteinaceous polymeric networks.

Constitutive modeling of dielectric elastomers has been of long standing interest in mechanics. Over the last two decades rigorous constitutive models have been developed that couple the electrical response of these polymers with large deformations characteristic of soft solids. A drawback of these models is that unlike classic models of rubber elasticity they do not consider the coupled electromechanical response of single polymer chains which must be treated using statistical mechanics. The objective of this paper is to compute the stretch and polarization of single polymer chains subject to a fixed force and fixed electric field using statistical mechanics. We assume that the dipoles induced by the applied electric field at each link do not interact with each other and compute the partition function using standard techniques. We then calculate the stretch and polarization by taking appropriate derivatives of the partition function and obtain analytical results in various limits. We also perform Markov chain Monte Carlo simulations using the Metropolis and umbrella sampling methods, as well as develop a new sampling method which improves convergence by exploiting a symmetry inherent in dielectric polymer chains. The analytical expressions are shown to agree with the Monte Carlo results over a range of forces and electric fields. Our results complement recent work on the statistical mechanics of electro-responsive chains which obtains analytical expressions in a different ensemble.

The antigen presentation molecule MR1 (major histocompatibility complex, class I–related) presents ligands derived from the riboflavin (vitamin B) synthesis pathway, which is not present in mammalian species or viruses, to mucosal-associated invariant T (MAIT) cells. In this study, we demonstrate that varicella zoster virus (VZV) profoundly suppresses MR1 expression. We show that VZV targets the intracellular reservoir of immature MR1 for degradation, while preexisting, ligand-bound cell surface MR1 is protected from such targeting, thereby highlighting an intricate temporal relationship between infection and ligand availability. We also identify VZV open reading frame (ORF) 66 as functioning to suppress MR1 expression when this viral protein is expressed during transient transfection, but this is not apparent during infection with a VZV mutant virus lacking ORF66 expression. This indicates that VZV is likely to encode multiple viral genes that target MR1. Overall, we identify an immunomodulatory function of VZV whereby infection suppresses the MR1 biosynthesis pathway.

Introduction Young adult hip pain is increasingly recognized as an early warning sign for development of debilitating arthritis later in life. Two common causes for young adult hip pain are femoroacetabular impingement (FAI) and dysplasia. Yet, no universal referral pathway exists in the UK for young patients experiencing hip pain. Our aim was to investigate the timeline and journey of patients seen in a specialist young adult hip clinic at a tertiary orthopaedic centre. Method We conducted a case series using a two-part open question questionnaire given to 40 patients at a young adult hip clinic at a tertiary orthopaedic centre between March and November 2019. Results Average time from onset of symptoms to appointment in specialist clinic was 2.9 (± 3.9) years, with range between 1 month and 23 years. Average time between first GP appointment and appointment at a tertiary centre was 2.1 (±2.4) years. A total of 33 (83%) patients were seen in secondary care prior to referral to a specialist clinic at a tertiary centre. Imaging modalities prior to attendance were as follows: 23 (58%) patients had a hip X-ray, 15 (38%) a CT scan, 30 (75%) an MRI scan and 6 (15%) an ultrasound scan of their hip. A total of 23 (58%) patients had corticosteroid injections prior to referral to a specialist clinic. Conclusions Large variation seen in our results highlights an opportunity for service improvement and development of a universal referral pathway to improve patient care and reduce burden on other services.

Congenital anomalies of the C2 vertebra involving the odontoid process are relatively common but anomalies involving posterior elements (lamina) of C2 are rare. Here we describe one such rare case of a 20 year old female patient who presented with the features of high cervical myelopathy due to CVJ anomaly with absent posterior elements of C2 along with C2-C3 spondyloptosis. The patient was operated for C1-C3 fixation & reduction of C2-C3 listhesis leading to improvement in neurological status. Only few such cases of the absent posterior arch of C2 have been reported so far. The available literature has been reviewed.

In the present investigation, a piezo-stack actuator coupled with a flexible diamond shaped frame has been investigated for its mechanical amplification property. The piezo-stack under elec...

Smart Manufacturing (SM) a revolutionary paradigm that aims to improve production systems’ performance in terms of quality, time, cost, and flexibility, as well as human and machine decision-making...

We study the isometric conical deformation of an inextensible elastic sheet in response to a distributed external loading that is normal to the deformed sheet. The sheet is planar in the reference configuration and it deforms into a cone with a flower-shaped cross-section under load. These deformed configurations are distinguished by the number of lobes. We focus on the geometry and energetics of various lobed-cones in the deformed configuration and discuss their relative stability. First, we assume that the displacements are small which leads to linear governing equations for the curvature that we solve analytically to yield sinusoidal solutions. Then, we relax this restriction on the magnitude of the displacement which leads to nonlinear governing equations, which we again solve analytically using Jacobi elliptic functions which are periodic but not sinusoidal. We show that the sinusoidal solution can be recovered in the limit that the external loads are small.

The purpose of this paper is to deliver a review of the implementation of the minimum quantity lubrication (MQL) system for manufacturing method, centring on the application of the MQL during the metal-cutting of workpiece. The application of MQL system was implemented & studied by various eminent investigators in last two decades. Thus, in this paper, experimental investigations of prior research work were discussed and analysed to light on review with significant facts for investigators and industries to optimize the metal-cutting process. During metal-cutting process, previous investigators considered three independent parameters like cutting speed, depth of cut and feed rate. Out of these parameters, feed rate was found to be most influencing parameter for response variables. But, for specific metal-cutting operation specific types of feed rate is required. Hence, the selection of optimum value & type of feed rate for specific machining operation is yet to investigated. This paper explored an evaluation of industry-socio based trial and error approaches and propose scope for improvement from both an economic and an environmental viewpoint. This paper delivers an outline of formerly conducted analysis to propose zones of enhancement in metal-cutting process employing minimum quantity lubrication system

A number of biological tissues and synthetic gels consist of a fibrous network infused with liquid. There have been a few experimental studies of the rheological properties of such gels under applied compressive strain. Their results suggest that a plot of rheological moduli as a function of applied compressive strain has a long plateau flanked by a steeply increasing curve for large compressive strains and a slowly decreasing curve for small strains. In this paper we explain these trends in rheological properties using a chemo-elastic model characterized by a double-well strain energy function for the underlying fibrous network. The wells correspond to rarefied and densified phases of the fibrous network at low and high strains, respectively. These phases can co-exist across a movable transition front in the gel in order to accommodate overall applied compression. We find that the rheological properties of fibrous gels share similarities with a Kelvin–Voigt visco-elastic solid. The storage modulus has its origins in the elasticity of the fibrous network, while the loss modulus is determined by the dissipation caused by liquid flow through pores. The rheological properties can depend on the number of phase transition fronts present in a compressed sample. Our analysis may explain the dependence of storage and loss moduli of fibrin gels on the loading history. We also point to the need for combining rheological measurements on gels with a microstructural analysis that could shed light on various dissipation mechanisms.

Ordered synthesis of one-dimensional nanostructures, such as carbon nanotubes (CNTs), involves competition between the growth kinetics of individual structures, their physical entanglement, and intermolecular forces that cause coupling of structures in close proximity. Specifically, CNT synthesis by chemical vapor deposition can directly produce films and fibers by providing CNT growth sites in close proximity such that the CNTs self-align into macroscopic assemblies. Because CNTs are mechanically coupled during these processes, the question arises as to whether or not mechanical forces intrinsic to the formation of CNT ensembles influence the growth kinetics and quality of CNTs, as can be expected from fundamental theories of mechanochemistry. Here, we study how mechanical forces influence CNT growth by applying controlled compression to CNT forests in situ; and relate the outcomes quantitatively to the CNT morphology and lengthening rate. We find that applied forces inhibit the self-organization of CNTs...

Allosteric interactions in DNA are crucial for various biological processes. These interactions are quantified by measuring the change in free energy as a function of the distance between the binding sites for two ligands. Here we show that trends in the interaction energy of ligands binding to DNA can be explained within an elastic birod model. The birod model accounts for the deformation of each strand as well as the change in stacking energy due to perturbations in position and orientation of the bases caused by the binding of ligands. The strain fields produced by the ligands decay with distance from the binding site. The interaction energy of two ligands decays exponentially with the distance between them and oscillates with the periodicity of the double helix in quantitative agreement with experimental measurements. The trend in the computed interaction energy is similar to that in the perturbation of groove width produced by the binding of a single ligand which is consistent with molecular simulations. Our analysis provides a new framework to understand allosteric interactions in DNA and can be extended to other rod-like macromolecules whose elasticity plays a role in biological functions.

We systematically study linear and nonlinear wave propagation in a chain composed of piecewise-linear bistable springs. Such bistable systems are ideal test beds for supporting nonlinear wave dynamical features including transition and (supersonic) solitary waves. We show that bistable chains can support the propagation of subsonic wave packets which in turn can be trapped by a low-energy phase to induce energy localization. The spatial distribution of these energy foci strongly affects the propagation of linear waves, typically causing scattering, but, in special cases, leading to a reflectionless mode analogous to the Ramsauer-Townsend effect. Furthermore, we show that the propagation of nonlinear waves can spontaneously generate or remove additional foci, which act as effective ``impurities.'' This behavior serves as a new mechanism for reversibly programming the dynamic response of bistable chains.

Water is an inorganic, non-flammable and easily available phase change material (PCM), which can be utilized for cold thermal energy storage (TES) application (melting point at 0°C). Although water has a specific heat of about 4.18 J g–1 K–1 and has melting enthalpy of about 333 J g–1, its application as an insulation layer was constrained. Phase separation (bulk convective movement during phase change, between ice and water), leakage from the container, supercooling during freezing, volumetric expansion and corrosion to the container were the main concerns for water as an insulation layer in TES systems. In this study, a thick non-flowing hydrogel (shape-stabilized PCM) was prepared by adding a small amount of inorganic additive material called LAPONITE® in water. The idea is to propose this thick non-flowing hydrogel as an insulating layer for cold TES application. The effect of this additive on viscosity and thermal properties of the water was studied. The phase change phenomenon of this hydrogel (between –10 and 20°C) was compared with water and the results are discussed.

The Jarzynski relation, as an equality form of the second law of thermodynamics, represents an exact thermodynamic statement that is valid arbitrarily far away from equilibrium. This remarkable relation directly links the equilibrium free energy difference between two states and the probability distribution of the work done along a process that drives the system from one state to the other. Here, we leverage the Jarzynski equality and a local equilibrium assumption, to go beyond the calculation of free energy differences and also extract the dissipation potential from additional measurements of kinematic field variables (strain and velocity fields). The proposed strategy is exemplified over pulling experiments of mass–spring models obeying overdamped Langevin dynamics, which is a prototype for nanorods, fibrous macro-molecules and the Rouse model of polymers. Different interaction potentials, fluid viscosities and bath temperatures are studied, so as to intrinsically control how close or far away the system is from equilibrium. The data-inferred continuum models are then validated against processes governed by different pulling protocols, thereby demonstrating their predictive capability. The methods presented here represent a first step toward full material characterization from non-equilibrium data of macroscopic observables, which could potentially be obtained from experimental observations.

Lay Summary During a kidney transplant, a plastic tube (stent) is placed in the ureter, connecting the new kidney to the bladder, in order to keep the new join open during the initial phase of transplantation. The stent is then removed after a few weeks via a camera procedure (cystoscopy), as it is no longer needed. The present study compared performing this in the operating theatre or in clinic for transplanted patients using a new single-use type of camera with an integrated grasper system. The results have shown that it is safe and cost-effective to do this in clinic, despite patients being susceptible to infection after transplantation.