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Pocket milling remains a key operation in the machining of aerospace structural components. This paper motivates a new combined-mode and feed-direction-dependent stability criteria to minimize pocket machining times, thereby improving productivity. Combined-mode milling models that include the influence of pre-existing slots in the workpiece to determine the optimal combination of engagements for up/down milling conditions are discussed in conjunction with feed-direction dependent stability models that exploit the role of dynamics projected in different feed directions to determine maximum machining stability limits. Model predictions supported by limited experimental validation demonstrate potential productivity gains of up to 60% using this new approach.

In this study, the hardness of polyvinylidene fluoride (PVDF), PVC and PVDF/PVC/GO (2.0 wt%) was estimated using piezoelectric and dielectric properties. The structure morphology was analyzed by Fourier transform infrared spectroscopy (FTIR). With the help of the solution casting technique, GO nanofiller were incorporated into PVDF/PVC matrix to prepare nanocomposites. In the case of PVDF/PVC/GO nanocomposites (2.0 wt%), the d33coefficient is comparatively higher. PVDF havelower dielectric constant, however, may be due to interfacial polarization occurring at the spherulites and at the polymer/filler interfaces. The achieved lower loss tangent (tanδ) for PVDF compared to PVDF/PVC and PVDF/PVC/GO (2.0 wt%) nanocomposites is attributed to PVDF highly insulating nature. The PVDF/PVC/GO (2.0 wt%) nanocomposite exhibited a d33value of ∼26 pm V−1, which was significantly higher than pure PVDF and PVDF/PVC.

Advanced metering infrastructure (AMI) is an important and integral component of Smart Grid. AMI requires a two way communication network to connect metering and load control endpoints spread over the residential area with the head end system. The most challenging part of AMI is to design this last leg of communication network which reliably and securely fulfills the requirement of the coverage, latency, scalability and compliance to country specific standards and regulations at the right cost. RF mesh technology is a proven way to implement the AMI network and this has been proven in the USA where the RF mesh networks have been functioning satisfactorily for more than a decade in the sub 1 GHz Industrial, Scientific and Medical (ISM) band with an available bandwidth of 26 MHz. In comparison, India has a narrow ISM bandwidth of only 2 MHz, which raises a doubt on achievement of AMI functionality within this constrained bandwidth. To carry out a high level feasibility for India, the relevant AMI data load and throughput requirements were estimated on the basis of data collected from published work and also through a survey involving Indian experts from utilities, regulatory bodies and metering companies. Based on the Pareto analysis of the estimated AMI data, the use case of ‘interval data push’ by the residential meters was considered for network simulation in a real world scenario of RF mesh AMI network. Utilizing only 20 % of the network capacity, for the estimated AMI data throughput of about 20 MB/day, the simulation exercise resulted in an estimate of size of network accommodating about 4800 endpoints per collector based on the acceptable latency of 5 s per hop.

The nanocomposites thin film was prepared by adding exfoliated GO in epoxy-hardner solution in different weight ratio. We investigate the thermal and surface properties of epoxy-graphene oxide (GO) nanocomposites using differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) and contact angle measurement method. AFM and contact angle results are supporting that graphene oxide provides the best reinforcement in epoxy. AFM is investigated the dispersion of GO and structural morphology of epoxy nanocomposites. The FTIR results show that exfoliated GO of two-dimensional (2D) shape favors the hardening process of the epoxy matrix, increasing its reaction rate by observing an epoxy stretching frequency at 907 cm−1. The GO modified with amino group of epoxy lead to the increase of crosslinking density. FTIR absorption peak in 1700–1500 cm−1regions is due to amino group. This attributes the significant increase of glass transition temperature of epoxy/GO nanocomposites . The contact angle and surface roughness increases with increase in concentration of GO in epoxy shows roughness induced hydrophobic surface. The solid surface energy was calculated by contact angle favors the good dispersion of GO in epoxy matrix.

The incidences of human pathogenic yeast Candida albicans and its related species acquiring resistance to antifungals have increased considerably, which poses serious problems towards its successful chemotherapy. The resistance of these pathogenic fungi is not restricted to the commonly used triazole compounds but is even encountered, though not often, with polyene derivatives as well. The efflux pump proteins belonging to ABC (ATP Binding Cassette) and MFS (Major Facilitators) super family are the most prominent contributors of multidrug resistance (MDR) in yeasts. The abundance of the drug transporters and their wider specificity suggest that these transporters may not be exclusively drug exporters in yeasts and may have other cellular functions. In this article we focus on some of the recent advances on the structure and function, evolution and transcriptional control of drug efflux proteins of Candida. A short discussion on the physiological relevance of drug transporters is also included.

Background: The platelet fibrinogen receptor, a heterodimer consisting of integrin subunits αIIband β3, is required for platelet aggregation, spreading, and hemostasis. Platelet agonists such as thrombin and adenosine diphosphate (ADP) lead to the activation of αIIbβ3, thereby enhancing its affinity and avidity for binding fibrinogen (inside‐out signaling). Furthermore, fibrinogen binding to αIIbβ3triggers cytoskeletal changes and granule release (outside‐in signaling).Aim: Genetic approaches to characterize the molecular pathways involved in αIIbβ3signaling are not possible with anucleate blood platelets. Therefore, we have established an OP9 stromal cell co‐culture system to generate megakaryocytes from human embryonic stem cells (hESCs).Results: αIIbβ3activation, measured by soluble fibrinogen binding to hESC‐derived megakaryocytes, ▪/GPIbα+cells, is readily detectable following stimulation with known platelet agonists. Dose–response curves for peptide agonists specific for the two platelet thrombin receptors, protease‐activated receptor 1 (PAR1) and PAR4, show a relative responsiveness that mirrors that of human platelets, and sub‐maximal ADP responses are augmented by epinephrine. Moreover, hESC‐derived megakaryocytes undergo lamellipodia formation, actin filament assembly, and vinculin localization at focal adhesions when plated on a fibrinogen‐coated surface, characteristic of αIIbβ3outside‐in signaling. Undifferentiated hESCs genetically modified by lentiviral infection can be cloned and maintained in an undifferentiated state and then differentiated into megakaryocytes capable of αIIbβ3activation.Conclusion: Using hESCs, we have developed a renewable source of human megakaryocytes, and a genetically tractable system for studying megakaryocytopoiesis and αIIbβ3signaling in the native cellular environment.

The analytical solutions for self-similar adiabatic flows behind a strong MGD shock advancing into a nonuniform self-gravitating gas atmosphere are obtained. The density ahead of the shock-front is assumed to satisfy the inverse power of the distance from the centre of explosion. The shock strength heading the disturbance and the total energy of the flow is assumed to be time dependent.