Electrochemical and microfabrication strategies for remotely operated heavy metal sensor networks for water analysis : the dual challenges of calibration-less measurement and sample pretreatment.

Current heavy metal monitoring in water utilizes sophisticated instrumental methods at centralized laboratories. For many applications, a preferable approach is the deployment of remote sensor networks. To this end, electrochemical methods in conjunction with microfabricated sensors potentially offer the required sensitivity and practical advantages including inexpensive sensors, reduced need for manual operation, reduced energy requirements, and also takes advantage of existing technologies such as communications networks for real-time data acquisition. The remote sensor platform developed herein consists of a photo-lithographically patterned gold electrode on SiO2 substrate within a custom stopped-flow thin-layer cell (TLC). Metal concentrations were evaluated by anodic stripping coulometry (ASC), where it was possible to pre-concentrate all dissolved metals from the finite TLC volume in about a minute. Unlike previously reported ASC approaches which rely on either linear sweep voltammetry or chronopotentiometry, the ASC variant described herein utilizes a potential step to simultaneously strip all deposited metals. The use of a double potential step ASC method also allowed in situ blank subtraction without the need for a separate blank solution. To achieve selectivity, several deposition potentials are used to pre-concentrate only those metals which can be reduced at a given potential. This method is demonstrated to be capable of measuring 500 ppb As(III) to better than 10% error even in the presence of high interferent levels (1.3 ppm Cu2+, 500 ppb Cd2+, 500 ppb Pb2+, and 5 ppm Zn2+). Similar performance was possible for As(III) spiked Ohio River water after pH adjustment. For more negatively reduced metals, dissolved oxygen (DO) reduction interferes with stripping analysis. An indirect in-line electrochemical DO removal device (EDOR), utilizing a silver cathode to reduce DO in a fluidically isolated chamber from the sample stream, was therefore developed. This device is capable of 98 % DO removal at flow rates approaching 50 µL/min with power consumption as low as 165 mW hr L-1. Besides our specific stripping application, this device is well suited for Lab on Chip (LOC) applications where miniaturized DO removal and/or regulation are desirable

Consociational Democracy and Peripheral Capitalism in Late-Modernising Societies: A Political Economy of Lebanon

Following the assassination of Prime Minister Hariri in 2005, Lebanon witnessed vigorous debate over the nature of its political system raising the question of whether it is based on consociation between confessions or consensus and balance of power between political factions. Lebanon has traditionally alternated between several extremes: from ‘the happy phenomenon’, a liberal example of self-perpetuating prosperity and ‘the only Arab democracy’ to a haven for warlords and the scene for recurring political impasses and violence. Underpinning these extremes, however, is the national myth that Lebanon is the ‘Switzerland of the East’. Whether this refers to its mountainous geography, freewheeling capitalism, salience of the tertiary sector or the politico-cultural cantonisation of the country is the subject matter of this research. This study explores political economy and political culture in Lebanon by locating the confessional subcultures within the theoretical framework of ‘hybrid modernities’. The research presented in this study, hence, aims to make sense of the perennial cycles of conflict and political impasses which have scarred modern Lebanese history. This is done by critically examining the intersections between consociationalism as a political superstructure, peripheral capitalism as a political economy and confessionalism as a political paradigm. The theory of ‘hybrid modernities’ is utilised in an attempt to redefine ‘modernity’ as an inclusionary and dynamic process whereby multiple socio-cultural projects are continually constructed and reconstructed through negotiation and conflict, hence, producing a hybrid order. Conflict is, therefore, interpreted as a mechanism of redistribution and negotiation between multiple subnational centres as opposed to a modality of state-society relations. Accordingly, the vulnerabilities of modernity and the unintelligibility of its constellations are mitigated not through bureaucratic universalism and the logics of the market, but through asymmetric relations of power between zu‘ama (patrons) and their ’atbā‘ (clients). The pervasiveness of political patronage, therefore, is not a relic of pre-modernity but a ‘modern’ and adaptive response to the disarticulations of Lebanese capitalism. Patron-client dyads capitalise on and reinforce social relations within vertical segments, hence, modernising and instrumentalising ‘the confession’. Social change, therefore, emanates from the subnational periphery (the confession) and targets the subnational and, eventually, the national centre. In responding to the aims and objectives of this study, ethnographic research was conducted to explore the intersections between the disarticulations of late developmentalism in Lebanon and the social construction of ‘imagined communities’. Focusing on the triangulation of consociationalism, peripheral capitalism and confessionalism as the political modus operandi in Lebanon and the Shi‘a as a subnational ‘imagined community’, this research explores the intersections between political economy and political culture in the production of multiple hybrid modernities within the multicentred Lebanese system. This is achieved by examining the political economy dynamics of the social construction of ‘the Shi‘a’ as well as the ontological worldviews and modus vivendi which underpin its socio-cultural project. In this context, Hezbollah is conceptualised as the ‘cohesive core’ of a social movement which articulates its own authenticated modernity and produces social change through a dynamic and bidirectional process facilitated by the party’s monolithic non-state welfare sector, civil society, media and the ulema

A Rising Star? Halal Consumer Protection Laws

The objective of this paper is to explore the legal aspects of the nascent halal regime in the United States. In Part I, an introduction to halal dietary laws is given. In Part II, a summary history of the halal industry—both business and legal—is exposited. Part III is an in-depth analysis of possible key learnings that can be gleaned from the kosher regime in America. Here, the similarities and differences between kosher and halal, a brief look at kosher developments, and the constitutional issues that have recently been plaguing kosher statutes are explored. Part IV attempts to tie the three previous sections together and considers the practical obstacles a successful halal regime will need to overcome. Finally, Part V concludes with a few suggestions and a look ahead

Preparation and Characterizations of Chitosan/Citral Nanoemulsions and their Antimicrobial Activity

Background and Objective: The antimicrobial activity of essential oils has been long recognized, however, they easily evaporate and/or decompose during preparation, owing to direct exposure to heat, pressure and light. The current study deals with the formulation and characterization of bio-based oil in water nanoemulsions and their antimicrobial activity against plant pathogens.Material and Methods: Citral oil and low molecular weight chitosan were used for preparation of nanoemulsions in the presence of sodium tripolyphosphate. Nanoemulsions were prepared by adding dropwise citral at different ratios into an aqueous solution containing chitosan, sodium tripolyphosphate and surfactant with continuous stirring and then ultrasonication. The success of formulation was confirmed by dynamic light scattering and scanning electron microscopy techniques. Physical stability and viscosity were investigated in details. The antimicrobial activity was evaluated against Erwinia carotovora, Aspergillus niger and Rhizopus stolonifer. Results and Conclusion: The nanoemulsions had a polydispersity index ranged from 0.508 to 0.614 and particle size from 27 to 1283 nm. The highest antimicrobial activity was observed with F1 formulation (EC50 = 23, 278 and 221 mg L-1, against Erwinia carotovora, Aspergillus niger and Rhizopus stolonifer, respectively). Based on the antimicrobial activity, the prepared chitosan/citral nanoemulsions can be a cost-effective way to protect crops from microbial pathogens. Because such formulations contain bioactive products, the development of resistant pathogens can be delayed.Conflict of Interest: The authors declare no conflict of interest.

Activation and contraction of human ‘vascular’ smooth muscle cells grown from circulating blood progenitors

Blood outgrowth smooth muscle cells offer the means to study vascular cells without the requirement for surgery providing opportunities for drug discovery, tissue engineering and personalised medicine. However, little is known about these cells which has meant their therapeutic potential remains unexplored. Our objective was to investigate for the first time the ability of blood outgrowth smooth muscle cells and vessel derived smooth muscle cells to sense the thromboxane mimetic U46619 by measuring intracellular calcium elevation and contraction. U46619 (10 26 -6 M) increased cytosolic calcium in blood outgrowth smooth muscle cells fibroblasts. Increased calcium signal peaked between 10-20 seconds after U46619 in both smooth muscle cell types. Importantly, U46619 (10-9 to 10-6 M) induced concentration-dependent contractions of both blood outgrowth smooth muscle cells and vascular smooth muscle cells but not in fibroblasts. In summary, we show that functional responses of blood outgrowth smooth muscle cells are in line with vascular smooth muscle cells providing critical evidence of their application in biomedical research

Four-leg active power filter control with SUI-PI controller

Four-leg active power filter is considered one of the greatest vital active filters that are frequently used in industrial applications, especially those that need to be controlled in each individual phase. Also, to control the neutral current that created because of a lot of unbalanced and non-linear loads. In this paper, the used active filter was controlled by a proposed control method which can achieve simplicity and intelligence at the same time. The novelty of this paper is using the proposed controller with Four-leg active power filter. This controller relies on instantaneous reactive power theory, which used to create the required currents that are injected into the network via the used active filter to remove the problems created by unbalanced and non-linear loads. It is also maintained that the current source a pure sinusoidal wave. The system is implemented on MATLAB/Simulink. The simulation results proved the preference of the proposed controller than the conventional proportional-integration controller, where it reduced the percentage of total harmonic distortion for the current source

Recent Developments in Nanomaterials-Based Drug Delivery and Upgrading Treatment of Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading causes of morbidity and mortality worldwide. However, despite the recent developments in the management of CVDs, the early and long outcomes vary considerably in patients, especially with the current challenges facing the detection and treatment of CVDs. This disparity is due to a lack of advanced diagnostic tools and targeted therapies, requiring innovative and alternative methods. Nanotechnology offers the opportunity to use nanomaterials in improving health and controlling diseases. Notably, nanotechnologies have recognized potential applicability in managing chronic diseases in the past few years, especially cancer and CVDs. Of particular interest is the use of nanoparticles as drug carriers to increase the pharmaco-efficacy and safety of conventional therapies. Different strategies have been proposed to use nanoparticles as drug carriers in CVDs; however, controversies regarding the selection of nanomaterials and nanoformulation are slowing their clinical translation. Therefore, this review focuses on nanotechnology for drug delivery and the application of nanomedicine in CVDs

Human microbiome and its association with health and diseases

Human microbiota are distinct communities of microorganisms that resides at different body niches. Exploration of the human microbiome has become a reality due to the availability of powerful metagenomics and metatranscriptomic analysis technologies. Recent advances in sequencing and bioinformatics over the past decade help provide a deep insight into the nature of the host-microbial interactions and identification of potential deriver genes and pathways associated with human health, well-being, and predisposition to different diseases. In the present review, we outline recent studies devoted to elucidate the possible link between the microbiota and various type of diseases. The present review also highlights the potential utilization of microbiota as a potential therapeutic option to treat a wide array of human diseases