Showing papers by "Indian Institute of Technology Kharagpur published in 2016"

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

Abstract: In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure flux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation, it is imperative to target by gene knockout or RNA interference more than one autophagy-related protein. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways implying that not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular assays, we hope to encourage technical innovation in the field.

Beamforming for Millimeter Wave Communications: An Inclusive Survey

Abstract: The remarkable growth of wireless data traffic in recent times has driven the need to explore suitable regions in the radio spectrum to meet the projected requirements. In pursuance of this, millimeter wave communications have received considerable attention in the research fraternity. Due to the high path and penetration losses at millimeter wavelengths, antenna beamforming assumes a pivotal role in establishing and maintaining a robust communication link. Beamforming for millimeter wave communications poses a multitude of diverse challenges due to the large channel bandwidth, unique channel characteristics, and hardware constraints. In this paper, we track the evolution and advancements in antenna beamforming for millimeter wave communications in the context of the distinct requirements for indoor and outdoor communication scenarios. We expand the scope of discussion by including the developments in radio frequency system design and implementation for millimeter wave beamforming. We explore the suitability of millimeter wave beamforming methods, both, existing and proposed till midyear 2015, and identify the exciting new prospects unfolding in this domain.

Chapter 4 – Fog Computing: principles, architectures, and applications

Abstract: The Internet of Everything (IoE) solutions gradually bring every object online, and processing data in a centralized cloud does not scale to requirements of such an environment. This is because there are applications such as health monitoring and emergency response that require low latency, so delay caused by transferring data to the cloud and then back to the application can seriously impact the performance. To this end, Fog computing has emerged, where cloud computing is extended to the edge of the network to decrease the latency and network congestion. Fog computing is a paradigm for managing a highly distributed and possibly virtualized environment that provides compute and network services between sensors and cloud data centers. This chapter provides a background and motivations regarding the emergence of Fog computing, and defines its key characteristics. In addition, a reference architecture for Fog computing is presented, and recent related development and applications are discussed.

Fog Computing: Principles, architectures, and applications

Abstract: The Internet of Everything (IoE) solutions gradually bring every object online, and processing data in a centralized cloud does not scale to requirements of such an environment. This is because there are applications such as health monitoring and emergency response that require low latency, so delay caused by transferring data to the cloud and then back to the application can seriously impact the performance. To this end, Fog computing has emerged, where cloud computing is extended to the edge of the network to decrease the latency and network congestion. Fog computing is a paradigm for managing a highly distributed and possibly virtualized environment that provides compute and network services between sensors and cloud data centers. This chapter provides a background and motivations regarding the emergence of Fog computing, and defines its key characteristics. In addition, a reference architecture for Fog computing is presented, and recent related development and applications are discussed.

Groundwater quality and depletion in the Indo-Gangetic Basin mapped from in situ observations

Abstract: Groundwater abstraction from the transboundary Indo-Gangetic Basin comprises 25% of global groundwater withdrawals, sustaining agricultural productivity in Pakistan, India, Nepal and Bangladesh. Recent interpretations of satellite gravity data indicate that current abstraction is unsustainable, yet these large-scale interpretations lack the spatio-temporal resolution required to govern groundwater effectively. Here we report new evidence from high-resolution in situ records of groundwater levels, abstraction and groundwater quality, which reveal that sustainable groundwater supplies are constrained more by extensive contamination than depletion. We estimate the volume of groundwater to 200 m depth to be >20 times the combined annual flow of the Indus, Brahmaputra and Ganges, and show the water table has been stable or rising across 70% of the aquifer between 2000 and 2012. Groundwater levels are falling in the remaining 30%, amounting to a net annual depletion of 8.0 ± 3.0 km3. Within 60% of the aquifer, access to potable groundwater is restricted by excessive salinity or arsenic. Recent groundwater depletion in northern India and Pakistan has occurred within a longer history of groundwater accumulation from extensive canal leakage. This basin-wide synthesis of in situ groundwater observations provides the spatial detail essential for policy development, and the historical context to help evaluate recent satellite gravity data.

Theoretical modelling of fog computing: a green computing paradigm to support IoT applications

Abstract: In this study, the authors focus on theoretical modelling of the fog computing architecture and compare its performance with the traditional cloud computing model. Existing research works on fog computing have primarily focused on the principles and concepts of fog computing and its significance in the context of internet of things ( IoT ). This work, one of the first attempts in its domain, proposes a mathematical formulation for this new computational paradigm by defining its individual components and presents a comparative study with cloud computing in terms of service latency and energy consumption. From the performance analysis, the work establishes fog computing, in collaboration with the traditional cloud computing platform, as an efficient green computing platform to support the demands of the next generation IoT applications. Results show that for a scenario where 25% of the IoT applications demand real-time, low-latency services, the mean energy expenditure in fog computing is 40.48% less than the conventional cloud computing model.

An Approach to Design Highly Durable Piezoelectric Nanogenerator Based on Self-Poled PVDF/AlO-rGO Flexible Nanocomposite with High Power Density and Energy Conversion Efficiency

Abstract: Till date, fabrication of piezoelectric nanogenerator (PNG) with highly durable, high power density, and high energy conversion efficiency is of great concern. Here a flexible, sensitive, cost effective hybrid piezoelectric nanogenerator (HPNG) developed by integrating flexible steel woven fabric electrodes into poly(vinylidene fluoride) (PVDF)/aluminum oxides decorated reduced graphene oxide (AlO-rGO) nanocomposite film is reported where AlO-rGO acts as nucleating agent for electroactive β-phase formation. The HPNG exhibits reliable energy harvesting performance with high output, fast charging capability, and high durability compared with previously reported PVDF based PNGs. This HPNG is capable for harvesting energy from a variety and easy accessible biomechanical and mechanical energy sources such as, body movements (e.g., hand folding, jogging, heel pressing, and foot striking, etc.) and machine vibration. The HPNG exhibits high output power density and energy conversion efficiency, facilitating direct light on different color of several commercial light-emitting diodes instantly and powers up many portable electronic devices like wrist watch, calculator, speaker, and mobile liquid crystal display (LCD) screen through capacitor charging. More importantly, HPNG retains its performance after long compression cycles (≈158 400), demonstrating great promise as a piezoelectric energy harvester toward practical applications in harvesting biomechanical and mechanical energy for self-powered systems.

Stop clickbait: detecting and preventing clickbaits in online news media

Abstract: Most of the online news media outlets rely heavily on the revenues generated from the clicks made by their readers, and due to the presence of numerous such outlets, they need to compete with each other for reader attention To attract the readers to click on an article and subsequently visit the media site, the outlets often come up with catchy headlines accompanying the article links, which lure the readers to click on the link Such headlines are known as Clickbaits While these baits may trick the readers into clicking, in the long-run, clickbaits usually don't live up to the expectation of the readers, and leave them disappointed In this work, we attempt to automatically detect clickbaits and then build a browser extension which warns the readers of different media sites about the possibility of being baited by such headlines The extension also offers each reader an option to block clickbaits she doesn't want to see Then, using such reader choices, the extension automatically blocks similar clickbaits during her future visits We run extensive offline and online experiments across multiple media sites and find that the proposed clickbait detection and the personalized blocking approaches perform very well achieving 93% accuracy in detecting and 89% accuracy in blocking clickbaits

Chemically Delaminated Free‐Standing Ultrathin Covalent Organic Nanosheets

Abstract: Covalent organic nanosheets (CONs) are a new class of porous thin two-dimensional (2D) nanostructures that can be easily designed and functionalized and could be useful for separation applications. Poor dispersion, layer restacking, and difficult postsynthetic modifications are the major hurdles that need to be overcome to fabricate scalable CON thin films. Herein, we present a unique approach for the chemical exfoliation of an anthracene-based covalent organic framework (COF) to N-hexylmaleimide-functionalized CONs, to yield centimeter-sized free-standing thin films through layer-by-layer CON assembly at the air-water interface. The thin-layer fabrication technique presented here is simple, scalable, and does not require any surfactants or stabilizing agents.

Carbon Dots Embedded Magnetic Nanoparticles @Chitosan @Metal Organic Framework as a Nanoprobe for pH Sensitive Targeted Anticancer Drug Delivery.

Abstract: Recently, nanoscale metal organic frameworks (NMOFs) have been demonstrated as a promising carrier for drug delivery, as they possess many advantages like large surface area, high porosity, and tunable functionality. However, there are no reports about the functionalization of NMOFs, which combines cancer-targeted drug delivery/imaging, magnetic property, high drug loading content, and pH-sensitive drug release into one system. Existing formulations for integrating target molecules into NMOF are based on multistep synthetic processes. However, in this study, we report an approach that combines NMOF (IRMOF-3) synthesis and target molecule (Folic acid) encapsulation on the surface of chitosan modified magnetic nanoparticles in a single step. A noticeable feature of chitosan is control and pH responsive drug release for several days. More importantly, doxorubicin (DOX) was incorporated into magnetic NMOF formulation and showed high drug loading (1.63 g DOX g(-1) magnetic NMOFs). To demonstrate the optical imaging, carbon dots (CDs) are encapsulated into the synthesized magnetic NMOF, thereby endowing fluorescence features to the nanoparticles. These folate targeted magnetic NMOF possess more specific cellular internalization toward folate-overexpressed cancer (HeLa) cells in comparison to normal (L929) cells.

Distributed manufacturing: scope, challenges and opportunities

Abstract: This discussion paper aims to set out the key challenges and opportunities emerging from distributed manufacturing (DM). We begin by describing the concept, available definitions and consider its evolution where recent production technology developments (such as additive and continuous production process technologies), digitisation together with infrastructural developments (in terms of IoT and big data) provide new opportunities. To further explore the evolving nature of DM, the authors, each of whom are involved in specific applications of DM research, examine through an expert panel workshop environment emerging DM applications involving new production and supporting infrastructural technologies. This paper presents these generalisable findings on DM challenges and opportunities in terms of products, enabling production technologies and the impact on the wider production and industrial system. Industry structure and location of activities are examined in terms of the democratising impact on participating network actors. The paper concludes with a discussion on the changing nature of manufacturing as a result of DM, from the traditional centralised, large-scale, long lead-time forecast-driven production operations to a new DM paradigm where manufacturing is a decentralised, autonomous near end user-driven activity. A forward research agenda is proposed that considers the impact of DM on the industrial and urban landscape.

Performance evaluation of microalgae for concomitant wastewater bioremediation, CO2 biofixation and lipid biosynthesis for biodiesel application

Abstract: This study was directed towards evaluating the potential of microalgae for simultaneous wastewater treatment, CO2 biofixation and lipid biosynthesis for biofuel application. The cultivation potential of various microalgal species in domestic wastewater (DWW) was studied in shake-flasks. The microalga, Scenedesmus sp. showed superior results in terms of the maximum specific growth rate of 0.44 d− 1, biomass yield of 0.43 g L− 1, biomass productivity of 61.4 mg L− 1 d− 1 and total lipid content of 23.1%. Subsequently, the performance evaluation of Scenedesmus sp. with respect to biomass growth, lipid accumulation, CO2 biofixation rate and nutrient uptake was carried out at different CO2 concentrations in a photobioreactor. The culture supplemented with 2.5% (v/v) CO2 was found most suitable and resulted in highest biomass productivity, total lipid content, lipid productivity, and CO2 consumption rate of 196 mg L− 1 d− 1, 33.3%, 65.17 mg L− 1 d− 1 and 368 mg L− 1 d− 1, respectively. The microalga could bioremediate ammonium, nitrate, phosphate and chemical oxygen demand (COD) efficiently from the wastewater to the extent of 70–98%. The FAME composition of the microalgal lipid was found encouraging for biodiesel application as saturated: unsaturated fatty acid ratio was favorable to about 1.2:1. The study indicates that Scenedesmus sp. can efficiently utilize DWW for its growth instead of using synthetic culture medium and can produce a significant amount of biomass at 2.5% CO2 for biofuel application.

Emerging new generation electrocatalysts for the oxygen reduction reaction

Abstract: The design and development of a new economically viable electrocatalyst for the cathodic reduction of oxygen in fuel cells and metal–air batteries is of significant interest. The high cost, scarcity and lack of durability of traditional Pt-based electrocatalysts limit the widespread implementation of fuel cells for practical applications. The emergence of non-Pt and metal-free electrocatalysts for the oxygen reduction reaction (ORR) is promising in the development of energy conversion devices. In this review, we discuss the emerging new electrocatalysts, non-precious transition metals, metal nitrides and carbides and the nanoscale carbon-based metal-free electrocatalysts, for the ORR. Although the actual ORR mechanism and the active site of these catalysts are not well understood, their catalytic activity is undoubtful. The porosity and chemical and electronic environments of the catalysts control their activity. The activity of these catalysts is discussed in terms of onset potential, durability and their tolerance towards anode fuels. The metal-free heteroatom-doped carbon-based electrocatalysts are highly active in alkaline medium, paving the way for the development of alkaline fuel cells, though their long time durability in an actual fuel cell stack is not well explored. The challenges in the use of these catalysts and the lack of fundamental understanding of the catalytic activity are addressed.

A ternary Cu2O-Cu-CuO nanocomposite: a catalyst with intriguing activity.

Abstract: In this work, the syntheses of Cu2O as well as Cu(0) nanoparticle catalysts are presented. Copper acetate monohydrate produced two distinctly different catalyst particles with varying concentrations of hydrazine hydrate at room temperature without using any surfactant or support. Then both of them were employed separately for 4-nitrophenol reduction in aqueous solution in the presence of sodium borohydride at room temperature. To our surprise, it was noticed that the catalytic activity of Cu2O was much higher than that of the metal Cu(0) nanoparticles. We have confirmed the reason for the exceptionally high catalytic activity of cuprous oxide nanoparticles over other noble metal nanoparticles for 4-nitrophenol reduction. A plausible mechanism has been reported. The unusual activity of Cu2O nanoparticles in the reduction reaction has been observed because of the in situ generated ternary nanocomposite, Cu2O–Cu–CuO, which rapidly relays electrons and acts as a better catalyst. In this ternary composite, highly active in situ generated Cu(0) is proved to be responsible for the hydride transfer reaction. The mechanism of 4-nitrophenol reduction has been established from supporting TEM studies. To further support our proposition, we have prepared a compositionally similar Cu2O–Cu–CuO nanocomposite using Cu2O and sodium borohydride which however displayed lower rate of reduction than that of the in situ produced ternary nanocomposite. The evolution of isolated Cu(0) nanoparticles for 4-nitrophenol reduction from Cu2O under surfactant-free condition has also been taken into consideration. The synthetic procedures of cuprous oxide as well as its catalytic activity in the reduction of 4-nitrophenol are very convenient, fast, cost-effective, and easily operable in aqueous medium and were followed spectrophotometrically. Additionally, the Cu2O-catalyzed 4-nitrophenol reduction methodology was extended further to the reduction of electronically diverse nitroarenes. This concise catalytic process in aqueous medium at room temperature revealed an unprecedented catalytic performance which would draw attention across the whole research community.

Modeling urban floods and drainage using SWMM and MIKE URBAN: a case study

Abstract: To avoid the nuisance of frequent flooding during rainy season, designing an efficient stormwater drainage system has become the need of the hour for present world engineers and urban planners. The present case study deals with providing a solution to stormwater management problem in an urbanized area. Mann–Kendall and Sen’s slope tests are used to perform the trend analysis of rainfall events using daily rainfall data (1956–2012), while the L-moments-based frequency analysis method is employed to estimate the design storm for a small urbanized area in West Bengal, India, using daily annual maximum rainfall (1975–2013). SWMM (Storm Water Management Model) and MIKE URBAN models are used to design an efficient drainage system for the study area. Two-dimensional (2D) MIKE URBAN model is primarily used to overcome the limitation of one-dimensional (1D) SWMM in simulating flood extent and flood inundation. Model simulation results from MIKE URBAN are shown for an extreme rainfall event of July 29, 2013. A multi-purpose detention pond is also designed for groundwater recharge and attenuating the peak of outflow hydrograph at the downstream end during high-intensity rainfall. This study provides an insight into the importance of 2D model to deal with location-specific flooding problems.

Enlightening surface plasmon resonance effect of metal nanoparticles for practical spectroscopic application

Abstract: Surface plasmon resonance (SPR) is the manifestation of a resonance effect due to the interaction of conduction electrons of metal nanoparticles with incident photons. The interaction relies on the size and shape of the metal nanoparticles and on the nature and composition of the dispersion medium. By understanding the mechanistic aspects of the interaction of altered nanoparticle morphologies together with the associated medium effect, a new technology has been developed for careful spectroscopic monitoring. Each change can be followed by various spectroscopic techniques, which lead to sensing applications and imaging events. From successful SPR band monitoring through spectroscopy, new optoelectronic technology and sensors, including color sensors and sensor devices, have been developed. In this review, we discuss the important role of SPR and its efficacy to heighten practical spectroscopic applications.

Computing for rural empowerment: enabled by last-mile telecommunications

Abstract: Increasing economic and educational exposure, and promotion of global health and wellness can be achieved through the power of sharing knowledge, technology, and resources. ICT can play a key role in disseminating such knowledge across the world. But a digital divide exists between urban and rural/remote areas, which results in economic and social disparities across regions. Developing last-mile telecommunication technologies for rural/remote areas is a crucial aspect in providing computing and ICT services that can integrate millions of stakeholders in rural/remote areas globally into the digital age, particularly with the advent of cloud computing. This article focuses on the different aspects of providing last-mile rural telecommunication access such as interfering factors, technology options, and deployment trends. This article aims to guide service providers, industry practitioners, and local entrepreneurs with a technology-and-deployment-trend analysis to choose, deploy, and operate suitable telecommunication networks depending on the unique features of the rural/remote area. Our goal is to bring attention to accessible and affordable technologies with practical considerations.

Dual channel closed-loop supply chain coordination with a reward-driven remanufacturing policy

Abstract: This paper investigates a reward-driven policy, employed in a closed-loop supply chain (CLSC), for acquiring used products earmarked for remanufacture. Under the examined model, a single manufacturer sells products through a retailer as well as directly to end users in a forward supply chain. In the reverse supply chain, three different modes of collection are employed to capture used products for remanufacture: they are through a third party, directly by the manufacturer and from the retailer. Mathematical models for both non-cooperative and centralised scenarios are developed to characterise the pricing decisions and remanufacturing strategies that indicate individual and overall supply chain performance. Optimality of all the proposed models is examined with theory. To coordinate and achieve a win–win outcome for channel members, we proposed a three-way discount mechanism for the manufacturer. Extended numerical investigation provides insights on ways to manage an efficient reward-driven CLSC in a dual...

Innovation, financial development and economic growth in Eurozone countries

Abstract: Using a panel vector auto-regressive model, we study interactions between innovation, financial development and economic growth in 18 Eurozone countries between 1961 and 2013. We focus on whether causality runs between these variables both ways, one way, the other way or not at all. Our empirical results show that development of the financial sector and enhanced innovative capacity in the Eurozone contributes to long-term economic growth in the countries in the region.

Single-Layer Wideband Microwave Absorber Using Array of Crossed Dipoles

Abstract: In this letter, a single-layer wideband absorber with compact thickness is proposed, and its ability to reduce the radar cross section (RCS) is investigated. The absorber consists of two-dimensional array of conductive crossed dipoles with lumped resistor elements on the top of a single-layer FR4 substrate, backed by continuous metallic layer. Simple methodologies for design and analysis of the absorber are presented. The thickness of the fabricated sample is less than 0.077λ L . (wavelength at the lowest cutoff frequency). It offers the 10-dB reflection reduction bandwidth of 70.7% (5.3-11.2 GHz) and full width at half-maximum (FWHM) absorption bandwidth of 104.76% (3.75-12 GHz). The experimentally demonstrated performance of the absorber shows good agreement with the numerical simulations.

Sustainable supply chain practices: an empirical investigation on Indian automobile industry

Abstract: The purpose of this research study is to analyze sustainable supply chain (SSC) management practices for Indian automobile industry and to identify the critical factors for its successful implementation. Despite the fact that SSC has been frequently promoted as a means of improving business competitiveness, little empirical evidence exists in the literature validating its positive link with organizational performance. Sustainable supply chain practices (SSCP) not only help in reducing environmental degradation but it also has social and economic implications (as per tipple bottom line approach). For this purpose, empirical data is collected to measure the SSCP prevailing in Indian automobile industry. A structural equation modeling technique is used to build the measurement and structural models. Later, statistical estimates are used to validate the model that has been built. The data analysis helps to determine whether to accept or reject the hypothesis that has been stated based on the structural model....