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In this work, we conducted a comparative analysis of the metal ion sensing capabilities of two pyridine‐end oligo p‐phenylenevinylene compounds featuring different alkyl substituents (−C4H9 and −C16H33) within a micelle medium. Our findings revealed a correlation between the positioning of the probe molecules within the micelle and the length of the alkyl chains, impacting their self‐assembly tendencies and optical characteristics. The compound with shorter alkyl chains demonstrated a superior affinity towards Hg2+ ions, whereas exposure to the compound with longer alkyl substituent resulted in a color‐changing response with both Cu2+and Hg2+ ions. Intriguingly, the sensitivity towards Hg2+ ions heightened with increasing alkyl chain length. This trend persisted in non‐polar solvents like THF. The capacity to modulate sensing efficacy solely by adjusting the length of the alkyl chains represents a relatively uncommon occurrence in the existing literature. This discovery suggests promising prospects for engineering sensory devices equipped with adaptable sensitivity. [ABSTRACT FROM AUTHOR]

Flexible dibenzimidazole based amphiphilic probe with indole as terminal residue has been synthesized using simple one‐step oxidative condensation. The compound formed nanoaggregates in the aqueous medium probably via extended intermolecular hydrogen bonding network involving benzimidazole moieties. The compound in monomer form (in THF) showed metal ion‐induced bathochromic shift, while in aggregate state (in water) metal coordination leads to hypsochromic shift. Moreover, in THF medium, compound interacts with large number of metal ions, whereas optical response was specifically observed with Hg2+ and Ag+ in the aqueous medium. Discrimination between Hg2+ and Ag+ was achieved using chloride as masking agent. Mechanistic investigations indicate formation of coordination‐driven supramolecular assembly where both benzimidazole and indole moieties participate in metal ion binding. The changes in microenvironment, such as local hydrophobicity, pH etc. showed distinct impact on metal ion sensing properties, both in terms of selectivity and sensitivity. Finally, the quantitative estimation of mercury, beyond its permissible level, was achieved in various natural water samples. [ABSTRACT FROM AUTHOR]

In the present work, we report a thermoresponsive hydrogel formed by the self-assembly of compounds 1 and 2 Milli Q water. Both hydrogels showed thixotropic behavior. Atomic force microscopy (AFM) studies confirm the fiber-like microstructure of compounds 1 and 2, but denser fibers were observed in the case of compound 1. The hydrogel formed by compound 1 detected Cu2+, Fe3+, and Hg2+, whereas the hydrogel of 2 showed a change in the optical signal, specifically upon adding Cu2+ and Hg2+. Mechanistically, adding metal ions to the hydrogel resulted in the formation of a (1:1) complex with Fe3+ and Hg2+ and (2:1) with Cu2+. The detection of metal ions has also been achieved in real-life samples, such as in tap water. Low-cost portable gel-coated paper strips have also been developed for the onsite detection of these metal ions. [ABSTRACT FROM AUTHOR]

Naked‐eye detection of an analyte at an ultralow concentration in a complex mixture is the ultimate goal of an analytical chemist. Over the years, with a wide range of sophisticated analytical techniques based on, for example, various microscopies (TEM, SEM, AFM), surface plasmon resonance (SPR) and surface‐enhanced Raman spectroscopy (SERS), one can achieve as low as single‐molecule detection. Despite their excellent sensitivities, these methods are often found to be unsuitable for on‐location analysis of real‐life samples due to limitations such as the requirement for advanced instrumental facilities and skilled technicians, high‐cost maintenance, and multi‐step sample preparation procedures. On the other hand, using the concept of molecular amplification a similar level of sensitivity can be achieved with changes in color or fluorescence as the output response. Unlike previous related reviews, in this work we chose not to focus on the different kinds of amplification strategies (target, label, signal, or receptor amplification) nor on the species responsible for generating reporter molecules (catalysts, macromolecules, metal surfaces, and supramolecular aggregates). Instead, herein we have attempted to discuss how the concept of molecular amplification has helped in the trace‐level detection of ionic analytes (for example, anions, heavy metal pollutants and charged biological molecules). [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) paradigm is a predominant research domain for smart cities, smart villages, society, and industry 4.0. The introduction of Unmanned Aircraft Systems (UAS) in an ultra-low latency network with fog, dews, and edge computing gives the researcher ample scope to establish a decentralized architecture for ultra-high-speed message exchange between IoT devices. This work mainly focused on Social Internet of Things ecosystem and its design to efficiently handle large group social gatherings, events, and emergency service management. We propose a layered message transfer framework for the social IoT scenario. We also establish network connection through flying ad hoc network architecture. The standard IoT message transfer protocol is redesigned by amalgamating with an opportunistic routing mechanism and deployed within 6G software-defined network (SDN) slice. We use seven distinguished network slices for different services and corresponding access. The study reveals nearly 99% of message delivery rate with a latency upper bound of 2300 ms by opportunistic message transfer scheme in a dense network scenario for QoS 2. It also shows 95% of the bandwidth utilization per slice and 97% of network coverage under SDN in quality of service level 2. [ABSTRACT FROM AUTHOR]

Pyrene-based fluorogenic amphiphilic probe (1) has been synthesized, which can form a thixotropic (injectable) hydrogel in the aqueous medium. The biocompatible hydrogel, so formed, is involved in the thermoresponsive, sustainable delivery of two anticancer drugs, Doxorubicin (DOX) and Mitoxantrone (MT). A substantial difference in the extent of drug release is noticed at 25 and 37 °C, even at physiological pH. The cumulative releases of ~80% and ~70% for DOX and MT, respectively, from the drug-loaded hydrogel samples, are observed for 72 h. In both cases, drug molecule release follows zero-order kinetics and non-Fickian diffusion pathways. The excellent stability of 1 against proteinase enzyme suggests that the present system can be used for sustainable, targeted release of drug molecules under in-vivo conditions. As expected, DOX-loaded hydrogels kill cancer cells more efficiently than the free drug (i.e., DOX). A pyrene-based amphiphilic probe has been synthesized, which can form a thixotropic hydrogel in the aqueous medium. The biocompatible hydrogel was involved in the thermoresponsive, sustainable delivery of two anticancer drugs, Doxorubicin (DOX) and Mitoxantrone (MT). Moreover, the DOX-loaded hydrogel could kill cancer cells more efficiently than the free drug. [ABSTRACT FROM AUTHOR]

• Design fluorescent phenazine probes using easily-scalable synthetic procedure. • Dual mode, ratiometric response towards Ag+ ion. • Metal ion-coordinated supramolecular aggregates with CT characteristics. • Critical role of terminal alkyl residues in metal ion coordination. • Selective, naked-eye, reversible sensing of iodide ions. The selective and sensitive detection of silver ions (Ag+) and iodide ions (I−) is of paramount importance in various scientific and industrial domains. In this paper, we present phenazine-based fluorescence probes, synthesized through a scalable and straightforward procedure, for the simultaneous sensing of Ag+ and I−ions in solution phase. The introduction of Ag+ led to ratiometric changes, manifesting in alterations of both solution color (from colorless to yellow) and fluorescence signal (from blue to cyan). Mechanistic investigations unveil that Ag+ coordinate with the phenazine nitrogen ends, forming self-assembled nanostructures characterized by significant charge-transfer properties. Moreover, we observed that the nature of the terminal alkyl residue played a pivotal role in governing the binding interaction with Ag+, with aliphatic residues featuring positively charged quaternary nitrogen ends exhibiting notably reduced responses. Additionally, the in-situ formed metal complex, comprising 1.Ag+, proved to be highly effective in selectively analyzing I− ions. The exceptional binding affinity of Ag+ for I− ions, marked by an exceptionally low solubility product constant, facilitated the sequestration of Ag+, ultimately leading to the formation of free probe in the reaction medium. Our research showcases the capability of phenazine-based probes in selective ion sensing applications, and their adjustable properties position them as promising options for a range of analytical and diagnostic uses. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present work, we have synthesized amphiphilic anthraimidazoldione derivative that can form nanoassembly in the aqueous medium. The π-conjugated backbone with facile intramolecular charge transfer from the substituted aryl residue to anthraquinone unit attributed to the profound orange color. Despite having the metal ion chelating aminoethyl acetamide unit, the compound showed no interaction with metal ions in the aqueous medium. However, a highly selective color-changing response, from orange to yellow (Δλ ∼52 nm), was observed upon addition of Hg2+ ion at micellar interface. Also, a turn-on fluorescence response (∼5.2-fold) was witnessed with Hg2+. It was observed that in addition to hydrophobic microenviroment, the orientation of molecules at water-surfactant interface also responsible for the chromogenic response towards Hg2+ ion. The mechanistic investigation indicated that Hg2+ ion coordinates with the aminoethyl acetamide unit, resulting restriction in the extent of intramolecular charge transfer. Considering such highly ratiometric response, the present system has been employed for analysis of Hg2+ ion in diluted urine and blood serum samples. The high recovery values (95.4 % to 104.3 %) with relatively low standard deviations (< 4.2 %) indicated that the present system is fairly successful in screening of complex real-life samples. Finally, we have designed low-cost, reusable, chemically modified paper strips for on-location, rapid analysis of mercury ions. [Display omitted] • Amphiphilic anthraimidazoldione derivatives form nanoassembly in water. • Nanomolar level detection of metal ion at micelle-water interface. • Metal ion coordination with aminoethyl acetamide unit, resulting in restricted ICT. • Analysis of Hg2+ ion in diluted urine and blood serum samples. • Chemically-modified paper strips for rapid, on-site detection of Hg2+. [ABSTRACT FROM AUTHOR]

[Display omitted] Pyrene-laced 'fluorescent' amphiphiles have been designed with a C4-alkyl chain as 'hydrophobic spacer' and sugar moiety as hydrophilic residue. The amphiphile containing acetylacetohydrazide as a bridging unit (1) showed gel formation both in water and ethanol medium, while no gelation was observed with compound (2) with acetohydrazide as bridging unit. Accordingly, the self-assembly behavior of 1 was thoroughly investigated both in water and EtOH medium (as well as in their mixtures) in addition to their physicochemical properties. Though the gel formation kinetics was slower in water medium, the hydrogel showed superior mechanical strength (and thixotropic behavior) and improved thermal stability compared to the ethanolic gel. In water, the percolating H-bonding network with high cohesive force restricts the dynamics of the probe molecules, leading to some extent limited intermolecular interactions. However, hydrophobic interactions in water medium can result in the formation of rather 'compact' nano-assembly (H-type aggregation) with prominent π-π stacking interactions. Such unique solvent-dependency of 1 was further utilized to screen commercially available beverages in terms of their alcohol contents and probe adulteration in beverages. Besides, the hydrogel also showed excellent stimuli responsiveness, a gel-to-sol transition, accompanied by fluorescence color change, was observed in the presence of insulin. [ABSTRACT FROM AUTHOR]

A reversible chromogenic probe based on a pyrene-linked bispicolyl amphiphile has been utilized for ratiometric, nanomolar level (LOD: 1.3 nM) detection of glyphosate in Brij-58 micelle medium. The probe shows a change in solution color from greenish-yellow to colorless with Cu2+ ions along with fluorescence quenching. When the solution was subsequently exposed to glyphosate, a ratiometric color-change from colorless to greenish-yellow was noticed, in addition to a turn-on fluorescence (green) response. Mechanistic investigations indicate dissociation of the preformed metal complex (1-Cu2+) in the presence of glyphosate, which triggers the release of unbound probe in the reaction medium. When 1-Hg2+ was used as the recognition template instead of 1-Cu2+, no interaction was observed with glyphosate. Considering its high sensitivity, 1-Cu2+ was further utilized for screening of real-life samples, such as water, soil, crops and packaged food items. Finally, the present sensory system is utilized for fluorescence bioimaging of intracellular glyphosate. [ABSTRACT FROM AUTHOR]

Predicting patients with major depression (MDD) is currently a difficult task. Magnetic resonance imaging (MRI) data analysis may provide insight into individual patient responses, allowing for more customized treatment decisions. Due to the absence of brain MRI data for MDD patients, a transfer learning (TL) method developed is used using calculation criteria. Combining an Inception‐v3 neural network with a typical pre‐trained neural network, the move learning‐based Inception‐v3 was proposed for the classification of MDD MRI datasets. An experiment was performed on the classification of eight semantic emotions (defined by IMAPS). Compared to other methods, the proposed method performs high efficiency for 90–10% and 80–20% (positive and negative classes), normal (N), unnormal (UN), and average/total sets, and for 70–30%, accuracy (A) is 92.90%, area under the curve (AUC) is 94.23%, and average precision score (APS) is 95.75%. Individual patients' responses to emotional stimulation can be predicted using the proposed methods, which can provide guidance in diagnosis and prognosis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ppb-level, ratiometric detection of pyrophosphate: Signal amplification. • Pyrophosphate induced demetallation which led to disassembly of probe molecule. • Electronic influence of spacer unit: rigid vs flexible spacer. • Detection in diluted blood serum samples and inside living cells. • On-location rapid detection using low-cost, reusable paper strips. In the present work, we have designed and synthesized two dimeric fluorescein derivatives with flexible salen (1) or a rigid salophen (2) linker unit. The Fe(III) complexes of these compounds ([ 1.Fe]+ and [ 2.Fe]+) showed changes in solution color specifically upon addition of inorganic pyrophosphate (PPi) at pH 7.0 in PBS buffer. Along this, we also observe appearance of green fluorescence (turn-on) in the prescence of PPi. The mechanistic studies suggested PPi-induced demetallation process, which led to disassembly for molecular structure in the aqueous medium and release of highly fluorescent fluorescein aldehyde. The disassembly process was found to be dependent on electronic structure, rigidity of the linker unit, temperature, and local pH etc. The selectivity as well as sensitivity of [ 1.Fe]+ towards PPi was also found to be superior than that observed with [ 2.Fe]+. Since each disassembly process released two signalling unit (fluorescein), we could observe a huge increment in FL intensity even with small quantity of PPi (<10 µM). Finally, the sensory system was utilized for detection of PPi in diluted blood serum samples and inside living mammalian cells (HeLa, cervical cancer cells). Chemically-modified paper strips have been developed for the detection of PPi in water samples at outside laboratory conditions. [ABSTRACT FROM AUTHOR]

Fluorescent nanoaggregates (FNAs) based on phenanthroline-based amphiphiles show changes in solution color from colorless to yellow upon addition of both Hg2+ (LOD ∼4 ppb) and CH3Hg+ (LOD ∼18 ppb). However, the extent of fluorescence quenching is more prominent with Hg2+ (∼12 fold) than with CH3Hg+ (∼4 fold). Also, unlike Hg2+, the interaction of CH3Hg+ needs more time, ∼10 min at room temperature. Experimental evidence indicates that both mercury species coordinate with the phenanthroline unit and facilitate the charge transfer interaction while destabilizing the nanoassembly. The lower charge density on CH3Hg+ along with its large size compared to Hg2+ may be the reason for such observations. Interestingly, FNAs show a selective response towards CH3Hg+ when pre-treated with EDTA. Further, analysis of heavy metal pollutants in drinking water and biological samples was performed. High recovery values ranging from 96% to 103.0% were estimated along with relatively small standard deviations (<3%). Low-cost, reusable test strips were designed for rapid, on-site detection of mercury species. Further, the in situ formed metal complexes are allowed to interact with thiol-containing amino acids. As expected, CH3Hg+, being less thiophillic, endures less interaction with cysteine. Mechanistic investigations indicate that thiolated amino acids can bind with the metal ion center and form a tertiary complex (cooperative interaction). [ABSTRACT FROM AUTHOR]

Highly colored oxidized 3,3/‐di(indolyl)arylmethanes (DIAM) based probes have been synthesized in good yield using modified single‐step synthesis. The internal charge transfer state of the molecules as well as protonation equilibrium of indolyl units are dominated by the electronic nature of substituents (R=−CH3, −NMe2, −NO2 etc) present on the central aryl moiety. However, irrespective to the nature of the substituents, all compounds (HL) show selective chromogenic response towards basic anions, like F− and H2PO4− etc in CH3CN. At low concentration, both analytes induce hypsochromic shifts in absorption maximum owing to the formation of H‐bonded complex (HL....A). However, only F− ion at high concentration results in a large bathochromic shift (▵λ∼90 nm) at λmax, probably due to the formation of deprotonated receptor (L−), attributed by higher stability of H‐bonded [HF2−] dimer. Thus, one can easily discriminate between these ions via color‐changing response. On the other hand, HSO4− being an acidic anion results in protonation of indolyl nitrogen center (H2L+) even at low concentration in CH3CN‐H2O (1 : 1) mixture medium, leading to bathochromic shift of absorption maxima. [ABSTRACT FROM AUTHOR]

In recent years, luminescent supramolecular coordination complexes (SCCs), including 2D‐metallacycles and 3D‐metallacages have been utilised for biomolecular analysis. Unlike small‐molecular probes, the dimensions, size, shape, and flexibility of these complexes can easily be tuned by combining ligands designed with particular geometries, symmetries and denticity with metal ions with strong geometrical binding preferences. The well‐defined cavities that result, in combination with the other non‐covalent interactions that can be programmed into the ligand design, facilitate great selectivity towards guest binding. In this Review we will discuss the application of luminescent metallacycles and cages in the binding and detection of a wide range of biomolecules, such as carbohydrates, proteins, amino acids, and biogenic amines. We aim to explore the effect of the structural diversity of SCCs on the extent of biomolecular sensing, expressed in terms of sensitivity, selectivity and detection range. [ABSTRACT FROM AUTHOR]

• This work proposes a Modified VGG19 deep-learning architecture to diagnose the Chest X-Rays. • This work computes the essential handcrafted features from the Chest X-Rays. • This work introduces an Ensemble of Features Scheme (EFS) by integrating the deep-features and the handcrafted features. • Serial fusion and PCA based selection is implemented in EFS to choose primary feature set. • Experimental results demonstrate superior performance of Modified VGG19 in comparison with AlexNet, VGG16, VGG19 and ResNet50. Pneumonia is one of the major illnesses in children and aged humans due to the Infection in the lungs. Early analysis of pneumonia is necessary to prepare for a possible treatment procedure to regulate and cure the disease. This research aspires to develop a Deep-Learning System (DLS) to diagnose the lung abnormality using chest X-ray (radiograph) images. The proposed work is implemented using; (i) Conventional chest radiographs and (ii) Chest radiograph treated with a threshold filter. The initial experimental evaluation is carried out using the traditional DLS, such as AlexNet, VGG16, VGG19 and ResNet50 with a SoftMax classifier. The results confirmed that, VGG19 provides better classification accuracy (86.97%) compared to other methods. Later, a customized VGG19 network is proposed using the Ensemble Feature Scheme (EFS), which combines the handcrafted features attained with CWT, DWT and GLCM with the Deep-Features (DF) achieved using Transfer-Learning (TL) practice. The performance of customized VGG19 is tested using different classifiers, such as SVM-linear, SVM-RBF, KNN classifier, Random-Forest (RF) and Decision-Tree (DT). The result confirms that VGG19 with RF classifier offers better accuracy (95.70%). When the similar experiment is repeated using threshold filter treated chest radiographs, the VGG19 with RF classifier offered superior classification accuracy (97.94%). This result confirms that, proposed DLS will work well on the benchmark images and in the future, it can be considered to diagnose clinical grade chest radiographs. To create your abstract, type over the instructions in the template box below. Fonts or abstract dimensions should not be changed or altered. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Social media conveys a reachable platform for users to share information. The inescapable practice of social media has produced remarkable volumes of social data. Social media gathers the data in both structured-unstructured and formal-informal ways as users are not concerned with the exact grammatical structure and spelling when interacting with each other by means of various social networking websites (Twitter, Facebook, YouTube, LinkedIn, etc.). People are increasingly involved in and dependent on social media networks for data, news and opinions of other handlers on a variety of topics. The strong dependence on social media network sites contributes to enormous data generation characterized by three issues: scale, noise, and variety. Such problems also hinder social network data to be evaluated manually, resulting in the correct use of statistical analytical methods. Mining social media data can extract significant patterns that can be advantageous for consumers, users, and business. Pattern mining offers a wide variety of methods to detect valuable knowledge from huge datasets, such as patterns, trends, and rules. In this work, data was collected comprised of users' opinions and sentiments and then processed using a significant number of pattern mining methods. The results were then further analyzed to attain meaningful information. The aim of this paper is to deliver a summary and a set of strategies for utilizing the ubiquitous pattern mining approaches, and to recognize the challenges and future research guidelines of dealing out social media data. [ABSTRACT FROM AUTHOR]

Speech Emotion Recognition (SER) has been widely used in many fields, such as smart home assistants commonly found in the market. Smart home assistants that could detect the user's emotion would improve the communication between a user and the assistant enabling the assistant to offer more productive feedback. Thus, the aim of this work is to analyze emotional states in speech and propose a suitable algorithm considering performance verses complexity for deployment in smart home devices. The four emotional speech sets were selected from the Berlin Emotional Database (EMO-DB) as experimental data, 26 MFCC features were extracted from each type of emotional speech to identify the emotions of happiness, anger, sadness and neutrality. Then, speaker-independent experiments for our Speech emotion Recognition (SER) were conducted by using the Back Propagation Neural Network (BPNN), Extreme Learning Machine (ELM), Probabilistic Neural Network (PNN) and Support Vector Machine (SVM). Synthesizing the recognition accuracy and processing time, this work shows that the performance of SVM was the best among the four methods as a good candidate to be deployed for SER in smart home devices. SVM achieved an overall accuracy of 92.4% while offering low computational requirements when training and testing. We conclude that the MFCC features and the SVM classification models used in speaker-independent experiments are highly effective in the automatic prediction of emotion. [ABSTRACT FROM AUTHOR]

Naked-eye sensing of phytic acid, one of the most abundant antinutrients, was achieved in 100% water medium using a charge transfer complex, composed of pyranine and methyl viologen. Since both the ingredients are commercially available, the design of such sensory systems needs zero synthetic effort, which essentially makes it economically viable. Only the physical mixture of both of these compounds showed a color-changing response from brown to yellow in the presence of phytic acid with a turn-on fluorescence response (LOD: 0.56 nM). The electrostatic interaction leads to charge pairing between phytic acid and methyl viologen, which releases free pyranine in solution. Considering its high sensitivity, low-cost test strips were developed for the on-site detection of phytic acid, even in remote locations. Additionally, estimation of phytic acid was achieved in grain samples with a sufficiently high accuracy, as evident from a sufficiently low relative standard deviation (<5%). [ABSTRACT FROM AUTHOR]

A Pyrene-based amphiphile with C4-alkanoyl spacer and lactose (PyLac) self-assembles in the aqueous media to form an injectable hydrogel. It shows preferential binding with Cholera Toxin (CT) via its terminal galactose residue, and hence can be employed for the selective detection of CT via color-changing response. [ABSTRACT FROM AUTHOR]

Traditional optical probes primarily work on the concept of one‐to‐one recognition strategy. Therefore, simultaneous detection of multiple anions is difficult using this kind of sensory systems. Similarly, designing of multi‐responsive array‐based materials is synthetically challenging as well as difficult to optimize. Thus, researchers across the globe became interested in developing single molecular probes, capable of detecting multiple anions (or anionic biomolecules) by simultaneously activating optically distinguishable output channels. Here, the modes of interaction largely depend on the structural features of the binding sites (cleft size, number of available coordination sites etc.), characteristics of the anions (ionic radius, hydration enthalpy, basicity, coordination number, pka of corresponding acids etc.) and the microenvironment around the probe molecules (micropolarity, viscosity, dielectric constant etc.) in the host matrix. In this review, we are mostly focusing on the structure‐activity relationships of such multiple anions sensing optical probes and their stimuli‐responsive properties. [ABSTRACT FROM AUTHOR]

Commercially available fluorogenic probe, 2‐ (2‐hydroxyphenyl) benzimidazole has been involved in detecting phosgene via ratiometric color changing response (cyan to blue). Mechanistic studies indicate formation of oxazolidone ring via double carbamylation reaction with phosgene, which significantly curb the extent of excited‐state proton transfer. On the other hand, involvement of weakly alkaline phenolic group as nucleophilic site ensures high specificity over structurally similar competitive analyte, such as triphosgene. Moreover, the present system can detect as low as 14.5 nM phosgene, which is ∼140 fold lower than the threshold value (2 ppm), known to cause immediate danger to health and life (IDLH). Also, detection of phosgene in gaseous state was achieved using dye‐coated paper strips (LOD: ∼0.16 ppm). A quenching in blue fluorescence was noticed when the strips were exposed to phosgene gas phase. Since no sophisticated analytical instrument, trained personnel or constant power supply is required, these paper‐based sensory devices are inexpensive and highly user‐friendly. [ABSTRACT FROM AUTHOR]

Multiresponsive smart optical probe based on p‐phenylene vinylene backbone is designed for simultaneous sensing of multiple ions, such as Cu2+, Zn2+ and F− at pH 7.4. A rapid color change from colorless to deep yellow is observed upon addition of both Cu2+ and Zn2+ ion. However, under long UV lamp, the green‐colored emission of the probe is specifically quenched in the presence of Cu2+, while Zn2+ induces change in the emission color from green to yellow. On the contrary, F−, unlike Cu2+ and Zn2+, does not render any change in visible color, however, an emission quenching, similar to that of Cu2+ addition, was noticed. The binding of metal ions to the central bipyridine core diminishes the 'conformational flexibility' and facilitates 'ligand to metal ion' charge transfer. On the contrary, addition of fluoride triggers the cleavage of silyl ether groups and results in the photo‐induced electron transfer from free hydroxyl groups to the core aromatic unit. Thus, we can detect as well as discriminate these three ions (Cu2+, Zn2+ and F−) simultaneously by comparing the respective output signals. Further, a sustainable strategy has been developed for on‐site detection of toxic ions using reusable, low‐cost paper strips. Most importantly, the current method is found to be fairly effective in quantifying (as evident by relatively smaller standard deviation values) the presence of toxic metal ions, above permissible levels, in a wide range of natural water samples. Further, estimation of fluoride is achieved in commercially available toothpaste and mouthwash products. [ABSTRACT FROM AUTHOR]

The handwritten digit recognition issue turns into one of the well-known issues in machine learning and computer vision applications. Numerous machine learning methods have been utilized to resolve the handwritten digit recognition problem. However, sometimes the digit is not completely present in the image due to issues related to scanning or environmental conditions (light, illumination, dirt, etc.). Although different efficient methodologies of handwritten digit recognition are proposed, there is not much work done on fragmented handwritten digit recognition. The objective of the proposed research work is to handle this circumstance to assemble a consistent digit recognition system that can precisely handle three types (English, Bangla, and Devanagari) of fragmented handwritten digit images. To solve the confusion, a technique is created to classify handwritten digits based on geometrical functions that are utilized to calculate handwritten digit features to assess if a digit belongs to a specific class. A grading scheme and a set of specified fuzzy rules determine the performance of classification. Experiments have been directed on the three familiar datasets, i.e., MNIST database (English), NumtaDB (Bangla) and Deva numeral database (Devanagari). Since fragmented digit delivers a lesser amount of information, the work also attempts to create a tentative size threshold above which outcomes become erratic and whether such thresholds are standardized or vary depending on other factors. Since the fragmented handwritten digital image does not have a public database, a method is formed to produce repeatable fragmented handwritten digital images from the entire image. Experimental outcomes validate that the proposed approach is effective in recognizing fragmented handwritten digits to an acceptable degree of fragmentation. [ABSTRACT FROM AUTHOR]

Flying Ad-Hoc networks (FANET) are the extended paradigm of the mobile Ad-Hoc networks and, perhaps, one of the most emerging research domains in the current era. A huge number of tangible applications have been developed in this domain. The main advantages of such networks are their easy deployment, scalability, and robustness. However, the sparseness of these networks is an inherent characteristic that is known to be a bottleneck. The main objective of this work was to provide an alternative solution for the intermittently connected FANET by considering the philosophy of the Delay Tolerant Network (DTN) approach. To realize the functionality of the DTN protocols in a three-dimensional (3D) space, a social FANET model is proposed. FANET nodes are supposed to have a sparse node density. Fundamentally, the proposed DTN assisted Flying Ad hoc Network exploits the DTN routing and mobility features. The new mobility modeling for 3D spaces was re-engineered and tested with well-known routing protocols to analyze the performance of the model based on node speed, density, buffer, latency, message overhead, and power consumption. The effectiveness of 3D mobility models has also been compared against the one of classical models. The obtained results reflect a significant enhanced performance of the suggested DTN protocol for sparse FANET in a social scenario. [ABSTRACT FROM AUTHOR]

The current letter presents a new model of creating flexible interconvertible logic circuits by using various chemical components as inputs out of a specifically designed molecule. Very distinct output optical signals were received when Hg2+ and F− ions were incorporated as specific inputs. Interestingly, the degrees of responses, as quantified by spectral changes, were altered in the presence of specific masking agents or water. Thus, to obtain the intended results, multiple concentration modulated reversible and irreversible spectroscopic experiments were designed in a case-specific manner to examine the changes in absorption spectra at multiple channels. Beyond conventional logic gates like NOR, OR, AND, and NAND, we were also competent to create several integrated logic circuits including IMPLICATION, INHIBIT, TRANSFER, and NOT-TRANSFER. It's amazing how simple it is to switch the sort of logic sense in this case thanks to optical toggling. [Display omitted] • Concentration regulated spectroscopic studies with Hg(II) & F−. • Design a series of trivial logic gates like NOR, OR, AND, and NAND out of the differential optical responses. • Integrated logic circuits, such as IMPLICATION, INHIBIT, TRANSFER, and NOT-TRANSFER, have been proposed. • Amazingly, optical toggling makes it straightforward to change the type of logic sense under such situations. [ABSTRACT FROM AUTHOR]

Bisindolyl based chromogenic probe with a bispicolyl binding site has been designed, that can form nanoscopic aggregates in water medium. The compound showed selective chromogenic response towards Cu2+ and Hg2+, solution color changes from red to light brown immediately as a result. Interestingly, we can specifically excite either monomer or aggregate species by choosing a suitable excitation channel. The compound showed turn-off response selectively upon addition of Hg2+ when excite at monomer excitation channel (λ ex = 390 nm). On the contrary, fluorescence quenching was observed with both Cu2+ and Hg2+ ions when excited through the aggregate channel (λ ex = 470 nm). Not only selectivity, but the sensitivity of the compound towards target metal ions depends on the excitation wavelength. Further, the detection of metal ions, such as Cu2+ and Hg2+ is performed in the biological matrices, such as diluted blood serum and plasma samples, etc. Finally, bioimaging of Hg2+ is achieved both in bacterial (E. Coli) and mammalian (HEK293T) cells. [Display omitted] • Design Bisindolyl based chromogenic probe with a bispicolyl binding site. • pH-sensitive nanoscopic aggregates formation in the aqueous medium. • Excitation-dependent modulation in sensing property: selectivity vs sensitivity. • Analysis of heavy metal pollutants in biological fluids. • Intracellular imaging of Cu2+ and Hg2+ ions. [ABSTRACT FROM AUTHOR]

• pH-sensitive nanoscopic aggregate formation in the aqueous medium. • Combinatorial effect of TICT and AIE on fluorescence response. • Dual mode, parts-per-billion level sensing of bisulfate ions. • Analysis of water samples and care-kit products for bisulfate. • Low-cost paper strips for on-site, rapid detection purpose. A donor-acceptor based fluorogenic probe, 4-(2-pyren-1-yl-vinyl) pyridine, 1 is synthesized that can form pH-sensitive nanoscopic aggregates in the aqueous medium. The fluorescence response of 1 in apolar solvents originates from LE state, while in polar solvents, it is dominated by TICT state. On the contrary, emissions from both TICT and AIE states is observed in water. A change in solution color from pale yellow to deep yellow is observed specifically upon the addition of HSO 4 ¯ ions with a concomitant change in fluorescence color. The mechanistic investigations indicate the hydrogen bonding interaction of HSO 4 ¯ ions with the pyridine nitrogen end, which can effectively alter the extent of charge transfer. Moreover, the interaction with HSO 4 ¯, leading to larger aggregate formation. Further, the current system is involved in the analysis of water samples and screening care-kit products. Finally, the dye-coated paper strips are designed for cost-effective, on-location detection of HSO 4 ¯. [Display omitted] [ABSTRACT FROM AUTHOR]

The common image related artifacts during image acquisition are noise caused due to external interference and imbalance in illumination. Uneven illumination correction incorporates a penalty term that performs intensity distribution, and transfer between pre-defined uniformly illuminated and non-uniformly illuminated sub-regions of the input scale image. Many methods exist in the literature to address illumination correction. In this study, an overview of illumination models, estimation, unevenly illuminated image processing, non-uniform illumination correction, background correction techniques, and shadow correction are delivered. Various real-life applications, in the field of remote sensing imaging, automatic medical diagnosis of different diseases, underground imaging, and document imaging depend on image quality and illumination conditions. Some of the related work done by different researchers in solving illumination correction is discussed in a sequel. Assessment of correction quality is difficult because of non-availability of unilluminated images. Some of the objective assessment techniques are also discussed in this survey. This study aims at putting forward an all-inclusive discussion on the application of non-uniform image processing by means of various existing correction models in a wide application domain, and their frequently encountered challenges. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Naked-eye sensing of Cu2+ and Hg2+ in physiological media. • Role of signaling unit in determining the stoichiometry of probe-metal ion complexes. • Estimation of toxic metal ions in natural water samples and also in presence of serum albumin. • Low-cost reusable paper strips for on-location detection purpose. Abstract Easy to synthesize probes are designed using bispicolyl moiety as the receptor unit with two different signaling moieties, anthraquinone and bisindolyl. Both the compounds show 'naked-eye' sensing of Cu2+ and Hg2+ in ∼100% aqueous medium. Not only selectivity, the compounds also show high sensitivity towards the target metal ions, as evident by their sufficiently low detection limits. The present system can detect Cu2+ as low as 0.06 ppm and Hg2+ up to 0.03 ppm from visible color change. The sensors are found equally effective in the detection of metal ions even in the protein-bound state. The impact of the signaling unit on the sensing properties of probes having same binding units has been observed and investigated. Mechanistic investigations revealed that variations in signaling unit influence the p K a of the bispicolyl nitrogens, which subsequently controls the stoichiometry of the probe-metal ion complexes as well as their luminescence property. Additionally, high specificity and good accuracy with recovery values ranging from 98.0 to 104.0% were obtained during Cu2+/Hg2+ estimation in spiked water samples. Low cost, reusable paper strips were developed for on-site detection of the metal ions which does not require the assistance of an optical instrument. [ABSTRACT FROM AUTHOR]

Abstract Plants species recognition is one of the most important research topics in the biological sciences. Although leaves are convenient markers for identification, a major drawback is that they are prone to be damaged easily by various environmental and biological factors. The proposed research work aimed to tackle this situation by proposing a leaf recognition system that can specifically handle fragmented leaf images. As leaf images are fragmented they can not be recognize based on shape features. Here a novel approach is proposed by using the combination of fuzzy-color and edge-texture histogram in order to recognize fragmented leaf images. First, the dataset leaf images that are similar to the query fragmented leaf image is identified by using bag-of-feature. Then, the combined feature is used to generate the feature vector. Since fragmented leaves provide less information, this work also attempted to derive a fragment size threshold beyond which results become unpredictable, and whether such thresholds are universal or vary depending on other factors. The efficacy of the proposed method was studied using a multi-layer-perceptron classifier. As there is no public database of the fragmented image, a method was designed to create the reproducible each fragmented leaf image from the whole corresponding one. [ABSTRACT FROM AUTHOR]

Despite decades‐long extensive research, probes that provide a comprehensive description of the lipid membrane microenvironment are still lacking. Here, a "smart" pyrene‐terpyridine probe for multiparametric sensing of lipid membranes is reported. The complexity of the associated local microenvironment can be described by the distinct features of the probe fluorescence. The self‐assembly of the probe molecules in phospholipid bilayers was sensitive to membrane order and phase state. The self‐assembled probes showed a unique emission, influenced by dye–dye interactions and excited‐state charge transfer. Moreover, this emission was sensitive to interfacial hydration, with very specific changes in emission wavelengths and fluorescence lifetimes upon variation of lipid compositions and properties. In parallel, changes in the lipid order and hydration affected the ground‐state interactions in the dye aggregates and, thus, could be measured through ratiometric changes in the excitation and emission readouts. In addition, fluorescence anisotropy measurements provided another way to study the nature of dye aggregates in lipid bilayers. Overall, this report demonstrates how multiple aspects of the membrane microenvironment can be sensed through the unique fluorescence signatures of this "smart" probe in lipid membranes, and it establishes a new paradigm in lipid‐membrane sensing. Probing lipid membranes: An amphiphilic pyrene‐based probe for comprehensive and multimodal readout of phospholipid membranes is described. [ABSTRACT FROM AUTHOR]

Two specific chemical receptive fields of brain, namely the amygdala and the orbital-frontal cortex, are related to valence and arousal in medical experiments. Functional magnetic resonance imaging (fMRI), which is a noninvasive, repeatable, and atomical tool for medical imaging in clinic system, was widely used in affective computing; however, it faces its dataset processing difficulty for dimensional reduction as well as for decreasing the computational complexity. In addition, features extraction from those de-dimensionality datasets is a challenging issue. The current work solved the de-dimensionality issue by using some preprocessing algorithms including clustering, morphological segmenting, and locality preserving projection. In order to keep useful information in fMRI dataset for reduction process, improved neighborhood pixel-based locality preserving projection (NP-LPP) algorithm was addressed and continuously for feature extraction operating using Otsu weighted sum of histogram. Furthermore, a modified covariance power spectral density (MC-PSD) separately in an fMRI Valence-Arousal experiments was measured. The results were analyzed and compared with affective norms English words system. The experiments established that the proposed methods of NP-LPP effectively simplified high complexity of fMRI, and Otsu weighted sum of histogram exhibited superior performance for features extraction compared to the MC-PSD through the calculation root mean standard error. The current proposed method provided a potential application and promising research direction on human semantic retrieval through medical imaging dataset. [ABSTRACT FROM AUTHOR]

Robotics are extensively utilized in modern industry to replace human labor and achieve high automation and flexibility. In order to produce large-size products, two-sided assembly lines are widely applied, where robotics can be employed to operate tasks on workstations. Since the applied traditional optimization methods are limited, the current work presented a new discrete cuckoo search algorithm to solve the two-sided robotic assembly line balancing problem. The original cuckoo search algorithm was modified by employing neighbor operations. Furthermore, a new procedure to generate individuals to replace the abandoned nests was developed to enhance the intensification. Since the considered problem has two subproblems, namely the robot allocation and assembly line balancing, the present work extended the cuckoo search algorithm to cooperative coevolutionary paradigm by dividing the cuckoos into two sub-swarms, each addressing a subproblem. In order to emphasize the exploration, a restart mechanism was employed. The proposed discrete algorithm’s evolution process and convergence were compared with another two popular optimization algorithms, namely the genetic algorithm and particle swarm optimization algorithm. Computational study on the proposed algorithms and other five recent algorithms along with statistical analysis demonstrated that the proposed methods yielded promising results. [ABSTRACT FROM AUTHOR]

A reversible ‘turn-on’ sensor has been designed for ‘naked-eye’ detection of oxalate at nanomolar concentration (∼12.5 nM) at pH 7.4. The sensory system shows a highly specific response towards oxalate among a wide range of antinutrients and biologically relevant anionic species. Mechanistic investigations indicate that oxalate can turn the pink-colored solution colorless by dissociating the preformed metal complex. Additionally, high specificity and good accuracy with recovery values ranging from 93.3 to 105.0% were obtained during oxalate estimation in spiked water and human urine samples, confirming the suitability of the present method in estimating trace-level of oxalate in complex matrices. With these results, quantitative estimations of endogenous oxalate were achieved in more than twenty-five different agricultural crops. Finally, low-cost, portable paper strips were developed for on-site detection of oxalate. [ABSTRACT FROM AUTHOR]

A donor–acceptor based conjugated microporous polymer, PER@NiP-CMOP-1, has been synthesized which can achieve highly sensitive stereo-specific “Turn ON” biosensing of an aminoglycoside up to the ppb level. The coordination-driven inhibition of photo-induced electron transfer (d-PET) for d-electrons and the rotational freezing are the key factors for the recovery of the emission. [ABSTRACT FROM AUTHOR]

An amphiphilic pyrene–terpyridine (Pytpy) probe forms novel, fluorescent nanoaggregates in phospholipid membranes. This unique membrane-driven self-assembly of Pytpy shows large Stokes shifts and long-lived fluorescent states and efficiently reports on vesicle–micelle transition through ratiometric changes. Strikingly, Pytpy can even distinguish between bilayer-like domains and more-dynamic micelle-like ‘rim’ phases that co-exist in mixed assemblies (bicelles). [ABSTRACT FROM AUTHOR]

Dengue fever detection and classification have a vital role due to the recent outbreaks of different kinds of dengue fever. Recently, the advancement in the microarray technology can be employed for such classification process. Several studies have established that the gene selection phase takes a significant role in the classifier performance. Subsequently, the current study focused on detecting two different variations, namely, dengue fever (DF) and dengue hemorrhagic fever (DHF). A modified bag-of-features method has been proposed to select the most promising genes in the classification process. Afterward, a modified cuckoo search optimization algorithm has been engaged to support the artificial neural (ANN-MCS) to classify the unknown subjects into three different classes namely, DF, DHF, and another class containing convalescent and normal cases. The proposed method has been compared with other three well-known classifiers, namely, multilayer perceptron feed-forward network (MLP-FFN), artificial neural network (ANN) trained with cuckoo search (ANN-CS), and ANN trained with PSO (ANN-PSO). Experiments have been carried out with different number of clusters for the initial bag-of-features-based feature selection phase. After obtaining the reduced dataset, the hybrid ANN-MCS model has been employed for the classification process. The results have been compared in terms of the confusion matrix-based performance measuring metrics. The experimental results indicated a highly statistically significant improvement with the proposed classifier over the traditional ANN-CS model. [ABSTRACT FROM AUTHOR]

Abstract: Herein, we report the formation of a highly luminescent, pH‐sensitive, thermoreversible nanoaggregate in pure aqueous medium through the self‐agglomeration of carbazole‐based amphiphiles. The self‐assembly process restricted the intramolecular motion of the molecules and induced a change in its emission signal from blue to cyan, owing to an aggregation‐induced emission (AIE) effect. A similar type of ratiometric response was also observed in the presence of human serum albumin (HSA). However, in this case, the molecular motion of the flexible fluorescent probe was restricted by its embedded microenvironment, owing to a motion‐induced change in emission (MICE) effect, not by aggregation. Moreover, the probe showed quite high selectivity for HSA over other serum albumin proteins. Our carbazole‐based fluorescent probes are a unique example of the ratiometric sensing of HSA through the sole involvement of reversible noncovalent interactions. Considering the important of HSA in clinical diagnosis, a wide range of biological fluids, such as human urine, saliva, and plasma, were screened to analyze their HSA content. In addition, this system was also employed for the detection of trypsin at subnanomolar concentrations through the digestion of HSA. [ABSTRACT FROM AUTHOR]

Excitation-dependent tuning of the emission behavior of fluorescent organic nanoparticles (FONs) with two simple luminescent pyrenyl–pyridyl conjugates as model systems is demonstrated. In the case of the compound with a flexible bis-picolyl moiety, the simultaneous presence of multiple ground-state species with distinct absorption and emission characteristics can be observed. The relative ratios of these species can easily be modulated, and it is possible to selectively stimulate any one of them individually by choosing an appropriate excitation channel. Moreover, at high concentration, a drastic change in the nature of the self-assembly is observed, which shifts from donor–acceptor-type self-assembly to exciplex-type self-agglomeration. On the contrary, the compound containing a rigid terpyridine unit has only a single ground state and shows no such tunable emission. However, it can exhibit multiple emission bands in water, whereby the positions of their emission maxima depend on the extent of aggregation-induced planarization of the probe molecules. Overall, this work demonstrates multimodal modulation of FON emission and a gives insight into how molecular order can translate into complete switching of nanoparticle self-assembly and photophysics. [ABSTRACT FROM AUTHOR]

Abstract: Excitation‐dependent tuning of the emission behavior of fluorescent organic nanoparticles (FONs) with two simple luminescent pyrenyl–pyridyl conjugates as model systems is demonstrated. In the case of the compound with a flexible bis‐picolyl moiety, the simultaneous presence of multiple ground‐state species with distinct absorption and emission characteristics can be observed. The relative ratios of these species can easily be modulated, and it is possible to selectively stimulate any one of them individually by choosing an appropriate excitation channel. Moreover, at high concentration, a drastic change in the nature of the self‐assembly is observed, which shifts from donor–acceptor‐type self‐assembly to exciplex‐type self‐agglomeration. On the contrary, the compound containing a rigid terpyridine unit has only a single ground state and shows no such tunable emission. However, it can exhibit multiple emission bands in water, whereby the positions of their emission maxima depend on the extent of aggregation‐induced planarization of the probe molecules. Overall, this work demonstrates multimodal modulation of FON emission and a gives insight into how molecular order can translate into complete switching of nanoparticle self‐assembly and photophysics. [ABSTRACT FROM AUTHOR]

Easily synthesizable amphiphilic probes have been designed for the detection of Al3+ exclusively at mesoscopic interfaces. The surface charge of the surfactant assemblies and the fluidity of the lipid aggregates show pronounced effects on the extent of Al3+ detection. Excellent sensitivity has been observed specifically in the presence of anionic surfactants and the lipid membranes with more sol-like characteristics. Moreover, a variation in the modes of Al3+ complexation is observed on shifting from one regioisomer to another. For instance, the para isomer exhibits a 1 : 2 stoichiometry with the Al3+ ion, while for the ortho-isomer, it is a 1 : 1 interaction. Considering the excellent sensitivity of the probe molecule towards Al3+, the present system has been utilized for the estimation of soluble aluminum content in acidic soil samples as well as in pharmaceutical tablets. Low-cost paper strips are developed for rapid, on-site detection of Al3+ without involving advanced instruments or trained technicians. Finally, the bioimaging of Al3+ is achieved in cervical cancer (HeLa) cells. [ABSTRACT FROM AUTHOR]

Cancer data analysis is significant to detect the codes that are responsible for cancer diseases. It is significant to find out the coding regions from diseases infected biological data. The infected data will be helpful to design proper drugs and will be supportable in laboratory assessments. Codes bear specific meaning on various features as well as symptoms of diseases. Coding of biological data is a key area to get exact information on animals to discover the desired medicine. In the current work, four different machine learning approaches such as support vector machine (SVM), principal component analysis (PCA) technique, neural mapping skyline filtering (NMSF) and Fisher’s discriminant analysis (FDA) were applied for data reduction and coding area selection. The experimental analysis established that the SVM outperforms PCA and FDA. However, due to the mapping facility, NMSF outperforms SVM. Thus, the NMSF achieved the preeminent results among the four techniques. Matthews’s correlation coefficient was used to evaluate the accuracy, specificity, sensitivity, F-measures and error rate of the four methods that are used to determine the coding area. Detailed experimental analysis included comparison study among the four classifiers for the deoxyribonucleic acid dataset. [ABSTRACT FROM AUTHOR]

The segmentation of medical images by computational methods has been claimed by the medical community, which has promoted the development of several algorithms regarding different tissues, organs and imaging modalities. Nowadays, skin melanoma is one of the most common serious malignancies in the human community. Consequently, automated and robust approaches have become an emerging need for accurate and fast clinical detection and diagnosis of skin cancer. Digital dermatoscopy is a clinically accepted device to register and to investigate suspicious regions in the skin. During the skin melanoma examination, mining the suspicious regions from dermoscopy images is generally demanded in order to make a clear diagnosis about skin diseases, mainly based on features of the region under analysis like border symmetry and regularity. Predominantly, the successful estimation of the skin cancer depends on the used computational techniques of image segmentation and analysis. In the current work, a social group optimization (SGO) supported automated tool was developed to examine skin melanoma in dermoscopy images. The proposed tool has two main steps, mainly the image pre-processing step using the Otsu/Kapur based thresholding technique and the image post-processing step using the level set/active contour based segmentation technique. The experimental work was conducted using three well-known dermoscopy image datasets. Similarity metrics were used to evaluate the clinical significance of the proposed tool such as Jaccard's coefficient, Dice's coefficient, false positive/negative rate, accuracy, sensitivity and specificity. The experimental findings suggest that the proposed tool achieved superior performance relatively to the ground truth images provided by a skin cancer physician. Generally, the proposed SGO based Kapur's thresholding technique combined with the level set based segmentation technique is very effective for identifying melanoma dermoscopy digital images with high sensitivity, specificity and accuracy. [ABSTRACT FROM AUTHOR]

Chromogenic probe with oxidized bis-indolyl scaffold has been synthesized for the detection of a nerve gas mimicking agent, DCNP (diethyl cyanophosphonate) at pH 8.0 in water. The mechanism of interaction was proposed as the release of cyanide ion through the indole group mediating the hydrolysis of phosphorous-hetero atom bond and, thereafter, the Michael addition of the liberated CN− ion to the electron deficient C=C bond of the bis-indolyl moiety. The reaction featured a remarkable change in color from red to colorless at ambient condition. Then, low-cost and portable paper strips were designed for a rapid and on-site vapor phase detection of DCNP without involving any sophisticated instrument or skilled personnel. Finally, a dye assembled inorganic nanocomposite material was devised to achieve a more sensitive ‘turn-on’ detection of DCNP in water. [ABSTRACT FROM AUTHOR]

Excitation triggered alteration in the sensing behavior of fluorescent nanoaggregates was explored in water, considering caffeine as the "target analyte". Merely by changing the excitation wavelength, we could specifically excite either the monomeric species or the fluorescent nano-aggregates. The monomer showed highly sensitive interaction with caffeine despite poor selectivity, while the "strongly associated" fluorescent nano-aggregates displayed relatively high selectivity with low sensitivity. In addition, the extent of self-aggregation was also found to be influenced by the micropolarity of the local surroundings and the electronics of the core carbazole unit. Furthermore, the present protocol was utilized for the estimation of caffeine in different beverages and biological fluids with reasonably high accuracy. Inexpensive, portable paper strips were designed for a rapid, on-site detection of caffeine without involving sophisticated instruments or trained technicians. [ABSTRACT FROM AUTHOR]

Easily synthesizable, fluorescent, organic nanoaggregates have been utilized, for the first time, in the selective recognition of d-(−)-ribose at pH 5.5 in water. In the self-assembled form, the reactive sites of the monomer units can be properly organized to form an effective 'recognition cleft' for ribose (limit of detection ≈23 μ m), in which binding mainly occurs through a combination of hydrogen-bonding and CH⋅⋅⋅π interactions. The degree of agglomeration shows a profound influence on the extent of ribose sensing. A reduction in the optical response (≈1.8-fold) is observed when ribose is allowed to interact with nanoaggregates of smaller dimensions (a decrease in the hydrodynamic diameter from (≈212.7±10.2) to (≈44.6±3.5) nm). The protocol is also utilized for the estimation of ribose in human urine samples and oral supplements. Low-cost paper strips have also been developed for rapid, on-site detection of ribose without involving any sophisticated instruments or skilled personnel. [ABSTRACT FROM AUTHOR]

Wireless technology development has increased rapidly due to it?s convenience and cost effectiveness compared to wired applications, particularly considering the advantages offered by Wireless Sensor Network (WSN) based applications. Such applications exist in several domains including healthcare, medical, industrial and home automation. In the present study, a home-based wireless ECG monitoring system using Zigbee technology is considered. Such systems can be useful for monitoring people in their own home as well as for periodic monitoring by physicians for appropriate healthcare, allowing people to live in their home for longer. Health monitoring systems can continuously monitor many physiological signals and offer further analysis and interpretation. The characteristics and drawbacks of these systems may affect the wearer?s mobility during monitoring the vital signs. Real-time monitoring systems record, measure, and monitor the heart electrical activity while maintaining the consumer?s comfort. Zigbee devices can offer low-power, small size, and a low-cost suitable solution for monitoring the ECG signal in the home, but such systems are often designed in isolation, with no consideration of existing home control networks and smart home solutions. The present study offers a state of the art review and then introduces the main concepts and contents of the wireless ECG monitoring systems. In addition, models of the ECG signal and the power consumption formulas are highlighted. Challenges and future perspectives are also reported. The paper concludes that such mass-market health monitoring systems will only be prevalent when implemented together with home environmental monitoring and control systems. [ABSTRACT FROM AUTHOR]

An easily synthesized fluorescein-based luminescent dye has been utilized for the dual-mode detection of histamine at nanomolar concentrations at pH 7.0 in water. The specific response to histamine was achieved by imidazole-catalyzed 'imine formation' reaction. The protocol was subsequently applied for the estimation of histamine in complex biological milieu such as human blood serum and urine samples. Furthermore, the dose-dependent cellular uptake of histamine and de novo synthesis (by thapsigargin treatment) was visualized in RAW 264.7, a mouse macrophage cell line. We have also developed portable paper strips for rapid, on-site detection of histamine without involving costly instruments. [ABSTRACT FROM AUTHOR]