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Abstract: In this paper we propose a specific sandwich immunoassay method for human-immunoglobulin G (HIgG). This immunoassay protocol takes advantage of sandwich binding of primary and secondary antibodies for increased specificity. Polystyrene microspheres (PS) serve as immobilizing support, site for sandwich immunoassay and then subsequently used for chemiluminescence (CL) detections. In this sandwich immunoassay, PS microspheres were modified with the primary anti-HIgG (Ab1) via electrostatic interaction, while CdTe nanoparticles (CdTeNPs) were modified with horseradish peroxidase labeled anti-HIgG (Ab2) via covalent binding. Antigen HIgG (Ag) was specifically captured by the first and secondary antibody and form sandwich immunoassay format. Combination of the remarkable sensitivity of CL method and the use of CdTe NPs as anti-HIgG–HRP carrier for the enzymatic signal amplification, provide a linear response range of HIgG from 0.01 to 300ngmL−1 with an extremely low detection limit of 0.3pgmL−1. This immunoassay system has many desirable merits including sensitivity, accuracy, and little required instrumentation. The assay results were compared with enzyme-linked immunosorbent assay (ELISA), and showed relatively good reliability. Significantly the new protocol may become quite promising technique for protein immune-detection as well as DNA analysis and other biological analyses. [Copyright &y& Elsevier]

Abstract: In this paper we developed an entirely new and highly sensitive luminol–H2O2 flow injection chemiluminescence system using the enhancement effect of CdTe quantum dots–IgG bioconjugates. Immunoglobulin G (IgG) as a kind of bio-molecule was conjugated to different sized CdTe semiconductor quantum dots (QDs). Using PL spectra and CL intensity profiles, it was found that chemiluminescence resonance energy transfer (CRET) was possibly occurring between CdTe–IgG bioconjugate and luminol. Under optimum conditions, increase of IgG concentration in CdTe–IgG bioconjugate resulted enhancing effect on CL intensity of luminol–H2O2 system. Moreover quenching effects on CL intensity by addition of different proteases can construct turn off biosensor for these proteases with low detection limits and wide linear range. Furthermore, the effects of various organic and inorganic species on CdTe–IgG bioconjugates enhanced luminol–H2O2 CL system were also studied in this paper. [Copyright &y& Elsevier]

Abstract: A highly sensitive flow-injection chemiluminescent method for the direct determination of pyrogallol compounds has been developed. Proposed method is based on the enhanced effect of pyrogallol compounds on the chemiluminescence signals of KMnO4–H2O2 system in slightly alkaline medium. Three important pyrogallol compounds, pyrogallic acid, gallic acid and tannic acid, have been detected by this method, and the possible mechanism of the CL reaction is also discussed. The proposed method is simple, convenient, rapid (60samplesh−1), and sensitive, has a linear range of 8×10−10 molL−1 to 1×10−5 molL−1, for pyrogallic acid, with a detection limit of 6×10−11 molL−1, 4×10−8 molL−1 to 5×10−3 molL−1 for gallic acid with a detection limit of 9×10−10 molL−1, and 8×10−8 molL−1 to 5×10−2 molL−1 for tannic acid, with a detection limit of 2×10−9 molL−1, respectively. The relative standard deviation (RSD, n =15) was 0.8, 1.1 and 1.3% for 5×10−6 molL−1 pyrogallic acid, gallic acid and tannic acid, respectively. The proposed method was successfully applied to the determination of pyrogallol compounds in tea and coffee samples. [Copyright &y& Elsevier]

Land is a pricy and scarce resource, particularly in urban areas. If it is utilized effectively, suitable sites can be allocated for urban wastewater safe disposal through effluents treatment and reuse. This study used multicriteria decision-making approach known as weighted linear combination to map the suitability of an on-site natural wastewater treatment system in the urban and industrial environments—selecting Faisalabad City in Pakistan as the study area. Location of the study region in a water-scarce zone increases the scope of the untreated wastewater disposal into land and water bodies as well as its reuse for irrigation. Data on climate parameters (i.e., temperature, rainfall, and evapotranspiration), geophysical parameters, (i.e., including soil, topography, depth to groundwater table, and groundwater electrical conductivity), and socioeconomic parameters (i.e., land cover maps and proximity from roads/railways and rivers/canals) are used for the development of weighted linear combination based suitability index maps. Analytical hierarchical process-based heuristic approach is adapted to estimate the relative importance of all the parameters. Weights with less than 0.10 consistency ratio are used in the preparation of the final suitability map. The land area required for the proposed on-site wastewater treatment system is estimated as a function of climatic factors and wastewater characteristics. Adoption of the proposed multicriteria framework helped identifying four potentially environment-friendly and economically viable sites. The results show that geospatial multicriteria framework could efficiently help urban planners in sustainable wastewater management, particularly in developing countries where climate-change-induced water scarcity and associated health issues are critical. • Better wastewater management in cities is critical for socio-ecological well-being. • A spatial framework for siting an on-site wastewater treatment plant is proposed. • The framework identifies potential ergonomic sites in a decentralized manner. • The framework acts as a decision-support-system for urban planning/design. • The application of the spatial framework is equally useful for other urban regions. [ABSTRACT FROM AUTHOR]

A green approach was employed for the synthesis of heterostructures of g-C 3 N 4 @MoO 3 and characterized by XRD, UV–vis, SEM and FTIR techniques to evaluate the structural, morphological, and optical features of the heterostructures. The XRD analysis revealed the high crystallinity and intensity of g-C 3 N 4 /MoO 3 higher than the g-C 3 N 4 and MoO 3. The g-C 3 N 4 shows a crumpled layered arrangement and a MoO 3 rod-like structure. The refractive index (n), bandgap energy (E g) and extinction coefficient (k) (optical properties) are determined by UV–vis spectroscopy. The g-C 3 N 4 /MoO 3 optical properties like k (2.15), n (2.37), dielectric coefficient (0.43), electronegativity (0.739) and bandgap energy (2.75 eV) were enhanced significantly. In visible region, the g-C 3 N 4 /MoO 3 demonstrated excellent performance for the degradation of RhB dye. The mobility and detachment of electron-hole pairs in type-II heterojunction semiconductors are responsible for the enhancement of photocatalytic activity (PCA) in visible region, which can be utilized for the dyes remediation in effluents under natural sunlight irradiation. [Display omitted] • A green route was employed for graphatic-C 3 N 4 @MoO 3 heterostructure synthesis. • Characterization was done by XRD, UV–vis, SEM and FTIR techniques. • The optical properties enhanced of g-C 3 N 4 @MoO 3 versus g-C 3 N 4 and MoO 3. • g-C 3 N 4 @MoO 3 showed promising catalytic activity under visible light irradiation. [ABSTRACT FROM AUTHOR]

Achieving Sustainable Development Goal (SDG)-4 prerequisites quality education provisioning. In this context, we present important insights and references for educational interventions/investments to be tailored to local necessities in Pakistan. Several spatial statistical models such as the Global Moran's I-based spatial autocorrelation, multivariate clustering, and the Cluster and Outlier model are used to explore geographic heterogeneities and patterns. Additionally, significant determinants among several socio-economic, spatio-environmental, and infrastructural variables are identified for education status (EdS) using regression. As a result, a large geographic inequality regarding EdS is found in Pakistan. While a strong spatial association is evident, the districts in northern Punjab are identified as significant hotspots—higher EdS clusters (∼22% of total districts, 95% confidence). Majority of the 44% poorly performing districts belong to Balochistan province (95% confidence). Overall, the educational status in Punjab is higher as compared with other provinces. We find that four out of seven potential factors (i.e., poverty, urbanization, electricity accessibility, and school infrastructure) are statistically significant determinants of EdS. Among these, poverty is the most strongly associated (mean coefficient value −18.848) factor to control EdS. The results have important implications to decision-making for immediate or gradual actions in the context of spatially equitable provisioning of quality education through an informed prioritization (i.e., low performing districts). Based on the findings, while rigorous measures are needed for low performing regions and the identified determinants to improve education status, this study sheds light on the mechanisms to achieve SDG4, consequently promoting human well-being through educating communities. • Pakistan's EdS is analyzed at the district-level. • Spatial-statistical techniques are coupled for EdS profiling. • While 44% districts show very poor EdS, poverty is the most significantly associated. • Lowest EdS is observed for districts in Balochistan province. • Results provide important references for policy, decisions, and actions to achieve SDG4. [ABSTRACT FROM AUTHOR]

Abstract: Polymers either serve as shielding or capping agents to restrict the nanoparticle size. This study demonstrates the polymer depositions and their effects in synthesis and sharp stabilization of gold nanoparticles (AuNPs) and to develop gold/silver nanoalloys (Au/Ag nanoalloys). Effects of different polymers are tested to justify their role in synthesis and stability of phloroglucinol (PG) coated AuNPs and Au/Ag nanoalloys. Cationic and anionic i.e. [Polydiallyldimethylammonium]+ (PDDA), [Polyethyleneimine]+ (PEI), [Polystyrene sulfonate]2− (PSS) and neutral polymer Polychlorotriflouroethylene (PCTFE) produce praiseworthy stable AuNPs and Au/Ag nanoalloy. To prove polymer effects characterization protocols including UV–vis, Fluorescence (PL), IR and AFM imaging are performed to fully investigate the mechanism and size characteristics of these nanoparticles/nanoalloys. In this study sharp size controlling/sheilding effects were observed particularly with cationic polymers simply through the favorable electrostatic interactions with the terminal ends of PG Potent/significant detection of doxorubicin (DOX, an antileukemic agent) via fluorescence resonance energy transfer (FRET) between PEI shielded AuNPs (AuNPEI) and DOX was achieved upto 10pM level, while PDDA protected AuNPs facilitated the detection of ascorbic acid based on fluorescence enhancement effects in wide range (10–200nM) and with detection limit of 200pM. Similarly sensing performance of PEI stabilized Au/Ag nanoalloys on addition of halides (Cl−, Br-, I−) is evaluated through red shifted SPR along with continuous increase in absorbance and also through AFM. Moreover the addition of halide ions also helped the regeneration of AuNPs by taking away silver from the Au/Ag nanoalloys enabling their detections upto subnanomolar levels. [Copyright &y& Elsevier]

[Display omitted] • Lumbrokinases are group of serine proteases. • Serine found at position 214 in lumbrokinase improved the activity of lumbrokinase. • In silico tools were used for characterization of mutant Lk-6 proteins. • Serine-Valin214 substitution were direct activation of breaking Arg561-Val562 bond. • The results of this study are step forward towards engineering smart lumbrokinases. Lumbrokinases (LKs) belong to the group serine proteases capable to prevent thrombosis through the proteolysis of both plasminogen-bound and plasminogen-free fibrin molecules. The article presents improved activity of Lumbrokinase-6 (Lk-6) by suggesting the substitution of a Serine found at position 214 (Lk-6) with three other amino acids namely Glutamic acid, Proline and Valine. To characterize the stability, enzyme-substrate interaction and improved activity of three mutant Lk-6 proteins (Lk-Glu214, Lk-Pro214, Lk-Val214) In Silico tools were utilized. Subsequently, Lk-6 wild type and three mutant proteins were subjected to structure prediction, molecular modeling, phylogeny, molecular docking and Protein-Protein Interaction (PPI) using the In Silico tools. Collection and analysis of results revealed that substituted mutation at Ser214 with Valine214 can appreciably stabilize the overall structure of Lk-6 protein and makes its interaction with plasminogen activator physically powerful for higher plasmin activation. Similarly, Serine214 to Valine214 substitution resulted the direct activation of plasmin breakage at the Arg561-Val562 bond. The Arg-Val at position 561–562 in plasminogen and its connection at catalytic site have significantly shown that the predicted residue Valine214 could be further examined through genetic engineering of Lk-6 protein. Therefore, such results are potential steps towards the engineering of smart and active Lks. [ABSTRACT FROM AUTHOR]

• A novel technique to enhance the proficiency of deep face recognition system. • Improving softmax by margining both multiplicative angular and additive cosine margin. • Most significant way to use these margins by not dividing into piece-wise function. • For testing, datasets have massive variation on age, pose and expression in face images. • Results has achieved on widely used benchmark datasets with low computational power. Face recognition in digital images or video frames has several real-world applications in the modern zone of computer vision. Loss function plays a vital role in deep face recognition. Recently, several loss functions have been proposed in classification techniques to reduce the number of model errors. Among several loss functions, softmax loss implemented either multiplicative angular or additive cosine margin. These individual margins have less capacity to reduce the model's errors. To fill this gap; we proposed a hybrid angularly discriminative features by combining multiplicative angular and additive cosine margin to improve the efficiency of angular softmax loss and large margin cosine. We trained proposed model using CASIA-WebFace dataset and testing has been performed on Labeled Face in the Wild (LFW), YouTube Faces (YTF), VGGFace1 and VGGFace2. The experimental result shows 99.77% accuracy on LFW dataset whereas 96.40% accuracy achieved on YTF dataset which is higher than the existing similar state-of-the-art techniques. [ABSTRACT FROM AUTHOR]

Abstract: Conventional synthesis of silver nanoparticles employs a reducing agent and a capping agent. In this report water-soluble silver nanoparticles (AgNPs) were prepared facilely by chemical reduction of Ag(I) ions. 4-Amino-3-(d-gluco-pentitol-1-yl)-4,5-dihydro-1,2,4-triazole-5-thione (AGTT) was used both as reducing and stabilizing agent. Direct heating methodology was found to be more suitable for achieving particles with a hydrodynamic diameter of ∼20nm. AGTT exists as tautomer in solution form and our studies indicate that –NH2 group is involved in the reduction and stabilization of Ag+ and thione (Δ=S) group of AGTT is possibly involved in stabilizing the nanoparticles via coordinate covalent linkage. Characterization of synthesized silver nanoparticles was performed by UV–vis, FT-IR and by FESEM. Based on the absorption properties of synthesized AgNPs, we used AgNPs to detect bovine serum albumin (BSA) and AgNPs-BSA composite nanoprobe was further applied to detect Cu2+ based on absorbance recovery. The proposed method has advantages over existing methods in terms of rapid synthesis and stability of AgNPs and their applications. Analysis is reproducible, cost effective and highly sensitive. The lowest detectable concentration of BSA in this approach is 3nM, and for Cu2+ it can detect upto 200pM. [Copyright &y& Elsevier]

Abstract: This paper presents the synthesis of aqueous CdTe QDs embedded silica nanoparticles by reverse microemulsion method and their applications as fluorescence probes in bioassay and cell imaging. With the aim of embedding more CdTe QDs in silica spheres, we use poly(dimethyldiallyl ammonium chloride) to balance the electrostatic repulsion between CdTe QDs and silica intermediates. By modifying the surface of CdTe/SiO2 composite nanoparticles with amino and methylphosphonate groups, biologically functionalized and monodisperse CdTe/SiO2 composite nanoparticles can be obtained. In this work, CdTe/SiO2 composite nanoparticles are conjugated with biotin-labeled mouse IgG via covalent binding. The biotin-labeled mouse IgG on the CdTe/SiO2 composite nanoparticles surface can recognize FITC-labeled avidin and avidin on the surface of polystyrene microspheres by protein–protein binding. Finally, the CdTe/SiO2 composite nanoparticles with secondary antibody are used to label the MG63 osteosarcoma cell with primary antibody successfully, which demonstrates that the application of CdTe/SiO2 composite nanoparticles as fluorescent probes in bioassay and fluorescence imaging is feasible. [Copyright &y& Elsevier]