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Introduction: Carotid artery stenosis is one of the important causes of ischemic stroke. This may be diagnosed by Doppler Ultrasound and Digital Subtraction Angiogram (DSA) both of which have some advantages and disadvantages. Objective: The aim of this study was to assess extra-cranial carotid artery with the help of DSA among patients of ischemic stroke and transient ischemic attack (TIA). Materials and Methods: This observational cross sectional study was conducted in the Department of Neurology in Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka from July 2013 to June 2015 for a period of two years. This study included a total of 50 patients. Diagnostic performance test of DSA was done at 50%, 50-69%, 70-99%, 100% cut off point of stenosis of right internal carotid artery (RICA) and Left internal carotid artery (LICA). Results: The mean age of cases was 61 ± 11.42 years. Out of 50 vessels, maximum cases were diagnosed as

Resistance to algae contamination is an important characteristic of insulators used in overhead power distribution in coastal environments. It is therefore important to understand the parameters governing algae adhesion onto polymer insulator materials such as silicone. Flow cell-based shear experiments were conducted in order to characterize the adhesion strength of algae onto polydimethylsiloxane surfaces, comparing fresh polymer substrates with those that have been soaked in water and saline solutions for 1 month. Both freshwater algae and seawater species could withstand considerably less drag force and were therefore more easily removed when the polymer was soaked in salt water. The polymer surface was found to be unaltered in terms of its roughness, contact angle, and lack of water uptake; no macroscopic surface characterization was therefore able to account for the differences in cell adhesion strength resulting from the soaking treatment. Surface-specific nonlinear vibrational spectroscopy, however, revealed subtle differences in the orientation of surface methyl groups that resulted from the water and saline exposure.

Textile fabrics with functional properties have a huge interest in many applications, including protective clothing, packaging materials, and healthcare, etc. This study aims to modify textile fabric’s surface and investigate the potentiality of Ag nanoparticles for the preparation of value-added and improved functional textiles. It demonstrates the mussel-inspired in-situ deposition of Ag nanoparticles on cotton fabric pre-modified by dopamine molecules. Surface characterization of nano-Ag deposited fabric is done by SEM (Scanning Electron Microscopy) and EDS (Energy Dispersive Spectroscopy) by which the well deposition of Ag nanoparticles is confirmed. The crystalline size of the Ag nanoparticles has been determined by SEM and X-ray diffraction spectroscopy. As functional properties, antimicrobial activity, UV protection, and crease resistance are investigated. The results reveal that the nano-Ag deposition introduces the excellent antibacterial property to cotton fabric against S. aureus (gram-positive) and E. coli (gram-negative). The fabric shows good UV protection power and significant crease resistance. The fabric has also been dyed with reactive dyestuff, and improved dyeing performance is found. Importantly, no significant changes in mechanical properties of the textile cotton fabric are found by surface modification and deposition of Ag nanoparticles.

The aim of the study was to determine serum ferritin level in transfusion dependent thalassaemia patients. A total of 64 transfusion dependent thalassaemia (TDT) patients was included in this cross sectional study from April, 2018 to September, 2019 according to selection criteria. Body iron load was estimated by serum ferritin level. The study sample consisted of 43 male and 21 female TDT patients, with a mean age of 25.5 years. Most of the patients (43.8%) patients had serum ferritin level in between 1000-2500 ng/ml. 12 patients (18.7%) had serum ferritin level >5000 ng/ml and 3 patients (4.7%) had serum ferritin in between 2501-5000 ng/ml. The mean serum ferritin was found 2462.6 ± 2792.7ng/ml with range from 207.0 -11891.2ng/m.

This paper comprehensively reviews driving behaviour in the context of heterogeneous traffic and poor lane discipline condition. Organising such driving behaviour models into two main groups (later...

Unconventional modes of transport (UCMs) play a substantial role in many developing cities in meeting the mobility demand in spite of having negative image in the eyes of the authorities. This manuscript outlines a conjoint framework where various factors affecting sustainability and competitiveness of UCMs are identified through observation study and organized using PESTLE qualitative framework. Afterwards, it presents an AHP-TOPSIS based qualitative approach where inputs from experts as well as major stakeholders (owners/operators, drivers, conductors and passengers) are combined based on the PESTLE framework to fathom the competitiveness of UCMs. Along this process, the manuscript also unveils the business model of UCMs along with their area of operation, advantages and weaknesses. For this, the study uses Dhaka, the capital city of Bangladesh as study area and selects three popular UCMs – locally known as Rickshaw, Easy bike and Leguna. The findings suggest that economic, social and political factors respectively have the highest influence among all factors of PESTLE. Rickshaw was found to be the most competitive followed by Easy bike and Leguna. The study is expected to shed light into the perception and expectation of major stakeholders of UCMs which in turn will provide valuable insight for designing conventional public transport services, and/or, help in slowly integrating the UCMs into the mainstream transportation service through addressing their shortcomings.

Extraordinary self-healing efficiency is rarely observed in mechanically strong hydrogels, which often limits the applications of hydrogels in biomedical engineering. We have presented an approach to utilize a special type of graphene oxide-based crosslinker (GOBC) for the simultaneous improvement of toughness and self-healing properties of conventional hydrogels. The GOBC has been prepared from graphene oxide (GO) by surface oxidation and further introduction of vinyl groups. It has been designed in such a way that the crosslinker is able to form both covalent bonds and noncovalent interactions with the polymer chains of hydrogels. To demonstrate the efficacy of GOBC, it was incorporated in a conventional polyacrylamide (PAM) and polyacrylic acid (PAA) hydrogel matrix, and the mechanical and self-healing properties of the prepared hydrogels were investigated. In PAM-GOBC hydrogels, it has been observed that the mechanical properties such as tensile strength, Young's modulus, and toughness are significantly improved by the incorporation of GOBC without compromising the self-healing efficiency. The PAM-GOBC hydrogel with a modulus of about 0.446 MPa exhibited about 70% stress healing efficiency after 40 h. Whereas, under the same conditions a PAM hydrogel with commonly used crosslinker

Background: BCR-ABL translocation is the most common genetic abnormality associated with adult Acute Lymphoblastic Leukaemia (ALL) with poor outcome. Objective: The aim of the study was to determine the association of myeloid aberrant antigens and the presence of BCR-ABL gene rearrangements in acute lymphoblastic leukaemia (ALL) patients in our context. Method: A total of 38 ALL patients were included in this cross-sectional study from August 2018 to July 2019 according to selection criteria. BCR-ABL was detected by Real Time-Polymerase Chain Reaction (RT-PCR). Results: The median age at diagnosis was 27.5 years with male (76.3%) predominance. Aberrant myeloid markers, e.g.CD13 was present in 9(64.3%) patients who were BCR-ABL positive which was statistically significant (p

The aim of the study was to determine the frequency of hypothyroidism in transfusion dependent thalassaemia patients. A total of 64 transfusion dependent thalassaemia (TDT) patients were included in this cross-sectional study from April, 2018 to September, 2019 according to selection criteria. Thyroid hormone status was assessed by estimation of serum FT4 and serum TSH. Body iron load was estimated by serum ferritin level. The study sample consisted of 43 male and 21 female TDT patients, with a mean age of 25.5 years. Total 28% patients were found hypothyroid, 11% were overt hypothyroid and 17% were subclinical hypothyroid. Mean serum ferritin level was 2462.6 ng/ml. Significant correlation was not found between serum TSH and Serum ferritin level (p = 0.055). Total unit of transfusion (p=0.001) and duration of transfusion therapy (p=0.003) were significantly associated with development of hypothyroidism.

The mechanical performances of hydrogels are greatly influenced by the functionality of cross-linkers and their covalent and non-covalent interactions with the polymer chains. Conventional chemical cross-linkers fail to meet the demand of large toughness and high extensibility for their immediate applications as artificial tissues like ligaments, blood vessels, and cardiac muscles in human or animal bodies. Herein, we synthesized a new graphene oxide-based two-dimensional (2D) cross-linker (GOBC) and exploited the functionality of the cross-linker for the enhancement of toughness and stretchability of a poly(acrylic acid) (PAA) hydrogel. The 2D nanosheets of GO were modified in such a way that they could provide multifunctional sites for both physical and chemical bonding with the polymer chains. Carboxylic acid groups at the surfaces of the GO sheets were coupled with the acrylate functional groups for covalent cross-linking, while the other oxygen-containing functional groups are responsible for physical cross-linking with polymers. The GOBC had been successfully incorporated into the PAA hydrogel and the mechanical properties of the GOBC cross-linked PAA hydrogel (PAA-GOBC) were investigated at various compositions of cross-linker. Seven times enhancement in both toughness and elongation at break has been achieved without compromising on the modulus for the as-synthesized PAA-GOBC compared to the conventional N,N′-methylenebis(acrylamide) (MBA) cross-linked PAA hydrogel. This facile and efficient way of GO modification is expected to lead the development of a high-performance nanocomposite for cutting-edge applications in biomedical engineering.

A combination of strong load-bearing capacity and high swelling degree is desired in hydrogels for many applications including drug delivery, tissue engineering, and biomedical engineering. However, a compromising relationship exists between these two most important characteristics of hydrogels. Improving both of these important properties simultaneously in a single hydrogel material is still beyond the satisfactory limit. Herein, we report a novel approach to address this problem by introducing a silica-based bi-functional 3D crosslinker. Our bi-functional silica nanoparticles (BF-Si NPs) possess amine groups that are able to offer pseudo-crosslinking effects induced by inter-cohesive bonding, and acrylate groups that can form conventional covalent crosslinking in the same hydrogel. We fabricated polyacrylic acid (PAc-Si) and polyacrylamide (PAm-Si) hydrogels using our BF-Si NPs via free radical polymerization to demonstrate this concept. Incorporation of the BF-Si crosslinkers into the hydrogels has resulted in a large enhancement in the mechanical properties compared to conventional hydrogel crosslinked with N,N′-methylene bisacrylamide (MBA). For instance, tensile strength and the toughness increased by more than 6 times and 10 times, respectively, upon replacing MBA with BF-Si in polyacrylamide hydrogel. Moreover, the hydrogels crosslinked with BF-Si exhibited a remarkably elevated level of swelling capacity in the aqueous medium. Our facile yet smart strategy of employing the 3D bi-functional crosslinker for combining high swelling degree and strong mechanical properties in the same hydrogels can be extended to the fabrication of many similar acrylate or vinyl polymer hydrogels.

The development of safe and cost-effective methods for the treatment of dye polluted wastewater has been a great concern among researchers. Herein, we developed a nanocomposite (M3D–PAA–CCN) based on polyacrylic acid (PAA) crosslinked with magnetic 3D crosslinkers (M3D) and carboxylated cellulose nanocrystals (CCN), for the removal of cationic dyes from aqueous solutions. Acrylic-functionalized Fe3O4 nanoparticles were covalently linked to the polymer chains via the form of the 3D crosslinker to introduce magnetic properties into the as-synthesized nanocomposite. The addition of highly dispersive CCN reduced the gel-like properties of the nanocomposite and instead incorporated a diffusive nature, which was more desirable for adsorbents. The surface morphology of the nanocomposite was analyzed by FESEM and the size of the nanocomposite particles was found to be in the range of 60–90 nm. The chemical functionalities and compositions were determined by XPS, FTIR, and EDX analyses whereas TGA confirmed the thermal stability of M3D–PAA–CCN. The maximum adsorption capacity of the M3D–PAA–CCN (332 mg g−1) was measured higher than that of M3D–PAA (114 mg g−1) to a cationic methylene blue (MB) dye indicating the significant contribution of CCN. The adsorption capacity of the as-synthesized M3D–PAA–CCN was found to be highly pH-dependent and the adsorption capacity increased with the increase of pH owing to the greater negative charge as indicated by the higher zeta potential. The adsorption kinetics of MB on the composites was found to follow the pseudo-second-order model. The adsorption capacity was also investigated as a function of concentration to figure out the adsorption mechanism using Langmuir and Freundlich isotherm models. The Langmuir model fitted the adsorption process better as suggested by the relatively smaller nonlinear chi-square value obtained from the fitting parameters.

The study of interfacial properties of thin films such as polymers is an important area of surface science. The application of visible–infrared sum-frequency generation spectroscopy to such systems...

This study investigates the potentiality of Ag nanoparticles for the preparation of value-added and improved functional textiles. It demonstrates the in-situ deposition of Ag nanoparticles on cotton fabric pre-functionalized by dopamine hydrochloride. Surface characterization of nano-Ag deposited fabric is done by SEM (scanning electron microscope) and EDS (energy dispersive spectroscopy) that confirms the shape and deposition of a higher amount of nano-Ag particles. The crystalline size and approximate shape are determined by X-ray diffraction spectroscopy. The results reveal that the nano-Ag deposition brings excellent performance on functional properties of cotton fabric. Antimicrobial activity is found as 82.60% reduction against S.aureus and 92% against E.coli measured by bacterial reduction rate (R%). The fabric also shows good UV protection power and admirable crease resistance. The fabric has also been dyed with reactive dyestuff and enhanced dyeing performance is found due to nano-Ag deposition. However, nano deposition causes a slight change in some important mechanical properties.

Spray generated by ships traveling in cold oceans often leads to topside ice accretion, which can be dangerous to vessels. To develop a full methodology of goal based design for ice accretion there are two critical knowledge gaps, both of which are complex to close, and require new methods and techniques. One is a comparison of ice accretion rates for different structures in the same icing conditions. The second knowledge gap is validation data that compares predicted ice growth rates for all types of ship and offshore structures against observed values. Estimation of the spray flux is a first step in predicting icing accumulation. The amount of spray water, the duration of exposure to the spray, and the frequency at which the spray is generated are all important parameters in estimating the spray flux. Most existing spray flux formulae are based on field observations from small fishing vessels. They consider meteorological and oceanographic parameters but neglect the vessel behavior. Ship heave and pitch motions, together with ship speed and heading relative to the waves, determine the frequency of spray events. Thus the existing formulae are not generally applicable to different sizes and types of vessels. The current study develops simple methods to quantify spray properties in terms that can be applied to vessels of any size or type, which consequently addresses the first knowledge gap. Formulae to estimate water content and spray duration are derived based on principles of energy conservation and dimensional analysis. To estimate spray frequency considering ship motions, a theoretical model is proposed. The model inputs are restricted to ship���s principal particulars, operating conditions, and environmental conditions. Wave-induced motions are estimated using semi-empirical analytical expressions. A novel spray threshold is developed to separate deck wetness frequency from spray frequency. Spray flux estimates are validated against full-scale field measurements available in the open literature and reasonable agreement was obtained. The complex interaction between the structure and a multi-phase fluid, including spray are not fully understood. Limitations of field measurements and model experiments encourage the use of numerical simulation to understand the formation of such spray. In this study, full-scale simulation models of wave-generated sea spray are also developed by implementing a smooth particle hydrodynamics (SPH) method. A three-dimensional (3D) numerical wave tank equipped with a flap-type wave maker and a wave absorber is created to produce regular waves of various heights and steepness. A full-scale medium-size fishing vessel (MFV) is modeled to impact waves in head sea conditions at various forward speeds. Moving ship dynamics with three degree-of-freedom (3-DOF) in waves are resolved instead of mimicking a relative ship speed. The resultant spray water amount is measured using a numerical collection box and compared against field measurements and the theoretical model, where a reasonable agreement is found. The model is able to distinguish between green water and spray water. A multi-phase two-dimensional (2D) simulation is also performed that demonstrates the role of wind in the fragmentation of water sheets into droplets and their distributions over the deck. The simulation results indicate energy released from a surging ship significantly contributes to the generation of spray. An investigation was also performed to explore means to speed up the computationally intensive SPH simulations. A comparison with a traditional CPU (central processing unit) clusters with GPU (graphics processing unit) was performed where GPUs demonstrated faster executions. All the SPH simulations were run on GPUs.

A recommendation system can assist the user to compose an understanding of requirements and propose informed decisions from a lot of complicated knowledge. Recommendation from an analysis of sentiments seems to be a great challenge as user-generated content is represented using human language in several complicated ways. Many studies have focused on common fields such as reviews of electrical items, films, and restaurants, but not enough on health and medical issues. Sentiment analysis of healthcare in general and that of the drug experiences of individuals, in particular, may shed considerable light on how to focus on improving public health and reach the correct decision. In this paper, we design and implement a drug recommender system framework that applies sentiment analysis technologies on drug reviews. The objective of this research is to build a decision-making support platform to help patients to achieve more significant choices in drug selection. Firstly, we propose a sentimental measurement approach to drug reviews and generate ratings on drugs. Secondly, we take how much the drug reviews are useful to users, patient's conditions, and dictionary sentiment polarity of drug reviews into consideration. Then, we fuse those factors into the recommendation system to list appropriate medications. Experiments have been carried out using Decision Tree, K-Nearest Neighbors, and Linear Support Vector Classifier algorithm in rating generation and Hybrid model in recommendation based on the given open dataset. The analysis is carried out to tune the parameters for each algorithm in order to achieve greater performance. Finally, Linear Support Vector Classifier is selected for rating generation to obtain a good trade-off among model accuracy, model efficiency, and model scalability.

In today’s era everybody is trying to be conscious about health. Although, due to workload and busy schedule, one gives attention to the health when any major symptoms occur. But Chronic Kidney Disease (CKD) is a disease which doesn’t shows symptoms it is hard to predict, detect and prevent such a disease and this can lead to permanently health damage, but some machine learning algorithms can come handy in this aspect for their efficient prediction and analysis. By using data of CKD, patients with 25 attributes and 400 records we are going to use various machine learning techniques like Random Forest, Support Vector Machine (SVM), K-Nearest Neighbors (KNN), Decision Tree etc. The purposes of our work is to virtuously predicting Chronic Kidney disease and have a comparative analysis among some of the popular machine learning based approaches based on some performance metrics. In our work, it is found that the Random Forest algorithm outperforming other machine learning based approaches we used in the experiment.

The molecular origin of overcharging at mineral oxide surfaces remains a cause of contention within the geochemistry, physics, and colloidal chemistry communities owing to competing “chemical” vs “physical” interpretations. Here, we combine vibrational sum frequency spectroscopy and streaming potential measurements to obtain molecular and macroscopic insights into the pH-dependent interactions of calcium ions with a fused silica surface. In 100 mM CaCl2 electrolyte, we observe evidence of charge neutralization at pH~10.5, as deducted from a minimum in the interfacial water signal. Concurrently, adsorption of calcium hydroxide cations is inferred from the appearance of a spectral feature at ~3610 cm-1. However, the interfacial water signal increases at higher pH, while adsorbed calcium hydroxide appears to remain constant, indicating that overcharging results from hydrated Ca2+ ions present within the Stern layer. These findings suggest that both specific adsorption of hydrolyzed ions and ion-ion correlations of hydrated ions govern silica overcharging with increasing pH.

Bimetallic nanocatalysts have been gaining huge research attention in the heterogeneous catalysis community recently owing to their tunable properties and multifunctional characteristics. In this work, we fabricated a bimetallic core–shell nanocomposite catalyst by employing a mussel-inspired strategy for immobilizing gold nanoparticles (AuNP) on the surface of nickel nanoparticles (NiNP). NiNPs obtained from the reduction of Ni(II) were first coated with polydopamine to provide the anchoring sites towards the robust immobilization of AuNPs. The as-synthesized nanocomposite (Ni–PD–Au) exhibited outstanding catalytic activity while reducing methylene blue (MB) and 4-nitrophenol (4-NP) yielding rate constants 13.11 min−1 and 4.21 min−1, respectively, outperforming the catalytic efficiency of its monometallic counterparts and other similar reported catalysts by large margins. The superior catalytic efficiency of the Ni–PD–Au was attributed to the well-known synergistic effect, which was experimentally investigated and compared with prior reports. Similar bio-inspired immobilization of AuNPs was also applied on graphene-wrapped NiNPs (Ni-G) instead of bare NiNPs to synthesize another composite catalyst (Ni-G–PD–Au), which yet again exhibited synergistic catalytic activity. A comparative study between the two nanocomposites suggested that Ni–PD–Au excelled in catalytic activity but Ni-G–PD–Au provided noteworthy stability showing ∼100% efficiency over 17 repeated cycles. However, along with excellent synergistic performance, both nanocomposites demonstrated high magnetization and thermal stability up to 350 °C ascertaining their easy separation and sustainability for high-temperature applications, respectively.

Paper and paper products are widely used without any antimicrobial efficacy in our everyday lives and thus can act as potential transporters of many diseases. Herein, we introduce antimicrobial activity to cellulose paper by presenting a tailored mussel-inspired strategy for the sustainable immobilization of silver nanoparticles (AgNPs), which are well-known for the effectiveness in preventing annexation and proliferation of microbes on materials surfaces. First, we functionalized the cellulose paper with succinic acid that eventually reacted with dopamine to give dopamine-modified paper. The dopamine molecules possess excellent adhesion and strong coordination with metal substrates through catechol groups offering a potentially robust interface between AgNPs and the organic structure of the paper. Next, AgNPs were deposited onto the paper by simply immersing dopamine-modified paper in a silver salt solution to accomplish the antimicrobial properties. Field emission scanning electron microscopic study of ...

Ba and Ta co-doped bismuth ferrites with the composition Bi 0.8 Ba 0.2 Fe 1-x Ta x O 3 (where x = 0, 0.05, 0.10 and 0.15) were synthesized employing a solid state reaction method. Rietveld refinement of XRD patterns revealed that Ba doping caused structural transformation in perovskite BFO from rhombohedral ( R 3 c ) to tetragonal ( P 4 mm ) with up to 10% Ta doping. However, with 15% Ta substitution (BBFTO-15) the ceramics exhibited a mixture of tetragonal and rhombohedral structures. Curve fitting of room temperature magnetization vs. magnetic field data showed that the shape of the hysteresis loops for these ceramics were the result of coexistence of single domain and superparamagnetic contributions. For 10% Ta substitution (BBFTO-10), the contribution from superparamagnetic particles was dominant. Polarization with respect to electric field measurements did not yield typical hysteresis loops; instead evidence of high leakage was present in BBFTO-0 and BBFTO-5 while that of BBFTO-10 and BBFTO-15 exhibited a lossy dielectric nature. The I-V characteristics confirmed that Ta doping reduced the leakage current by greater than two orders of magnitude compared to BBFTO-0. It is believed that the reduction in oxygen vacancy in the doped samples was key in reducing the leakage current. As a matter of fact, XPS data revealed a reduction in oxygen vacancy concentration and the percentage of Fe 3+ was also found to increase with increasing Ta doping. Dielectric constant and dielectric loss were also found to decrease with the increase of Ta doping. Impedance spectroscopy confirmed the contribution from multiple impedance components including evidence of a dipolar relaxation that was found in BBFTO-5 and BBFTO-10. Defect associates were proposed to be responsible for such relaxations.

Vibrational sum frequency generation (SFG) spectroscopy was utilized to distinguish different populations of water molecules within the electric double layer (EDL) at the silica/water interface. By systematically varying the electrolyte concentration, surface deprotonation, and SFG polarization combinations, we provide evidence of two regions of water molecules that have distinct pH-dependent behavior when the Stern layer is present (with onset between 10 and 100 mM NaCl). For example, water molecules near the surface in the Stern layer can be probed by the pss polarization combination, while other polarization combinations (ssp and ppp) predominantly probe water molecules further from the surface in the diffuse part of the electrical double layer. For the water molecules adjacent to the surface within the Stern layer, upon increasing the pH from the point-of-zero charge of silica (pH ∼2) to higher values (pH ∼12), we observe an increase in alignment consistent with a more negative surface with increasing...

Specific ion effects (SIEs) are known to influence the acid/base behavior of silica and the interfacial structure of water, yet evidence of the effect of pH on SIEs is lacking. Here broadband vibrational sum frequency generation (SFG) spectroscopy was used to study SIEs on the water structure at the electrical double layer (EDL) of silica as a function of pH and monovalent cation identity from pH 2–12 at 0.5 M salt concentration. SFG results indicate a direct Hofmeister series of cation adsorption at pH 8 (Li+ 10. In addition, an inversion in SFG intensity trends also occurred at pH < 6, which was attributed to contributions from asymmetric cation hydration and EDL overcharging. The highly pH-dependent SIEs for silica/water have implications for EDL models that often assume pH-independent parameters.

The structure of water adjacent to silica is sensitive to the degree of deprotonation of surface silanol groups. As a result, close inspection of signals originating from these water molecules can be used to reveal the surface charge density. We have used nonlinear vibrational spectroscopy of the water O–H stretching band over a temperature range of 10–75 °C to account for the increase in surface potential from deprotonation. We demonstrate that the behavior at the silica surface is a balance between increasing surface charge and a decreasing contribution of water molecules aligned by the surface charge. Together with a model that accounts for two different types of silanol sites, we use our data to report the changes in enthalpy and entropy for deprotonation at each site. This is the first experimental determination of these thermodynamic parameters for hydrated silanol groups at the silica surface, critical to a wide range of geochemical and technological applications.

Here, we report a novel fabrication of a magnetic carbon nanotube-reduced graphene oxide-silver nanocomposite for the adsorption and simultaneous catalytic reduction of two environmental pollutants. Fe3O4 nanoparticles were grown and anchored onto the multi-walled carbon nanotube (CNT) first to generate magnetic CNT (MCNT), which was further coated with polydopamine to enhance the stability of the Fe3O4 particles and introduce new functionalities on the surface. Hydrothermal treatment of the polydopamine-coated MCNT (PD-MCNT) with graphene oxide (GO) produced a highly carbonaceous reduced GO-PD-MCNT (rGO-PD-MCNT), which by itself exhibited very high adsorption capability. The catalytic property was integrated by depositing silver nanoparticles (AgNPs) on the rGO-PD-MCNT by reducing Ag(I) ions. High catalytic efficacy besides fast and efficient adsorption of the as-synthesized nanocomposites was demonstrated at variable pH during the removal of a toxic model dye, methylene blue (MB), and an aromatic nitro compound, 4-nitrophenol (4-NP). The nanocomposites were found to be magnetically separable, easily regenerable through desorption using water and ethanol, and thus highly recyclable (more than 15 cycles). The rare combination of all these properties in a single scaffold makes this nanocomposite potentially useful in a wide range of engineering and environmental applications.

Lycopene was extraction, isolation and purification using recrystallization, column chromatography, and preparative thin layer chromatography (TLC) methods as well as degradation kinetics of lycopene were studied at refrigerated temperature and room temperature for 3 wk from watermelon. Higher lycopene degradation was observed at refrigerated temperature as compared to ambient temperature throughout the storage periods. The highest amount of lycopene retained in recrystallization (101.69 μg/g) followed by column chromatography (18.20 μg/g) and preparative TLC (15.57 μg/g). Color parameters, half-life time (t1/2 ), and color retention (%R) were dependent on extraction, isolation, and purification methods and storage life. Recrystallization and preparative TLC were followed by first order reaction model. Preparative TLC exhibited higher activation energy than did the recrystallization and column chromatography. Therefore, the result shows that recrystallization method could apply to extract and purify lycopene from watermelon that would also be used as a natural colorant as well as value-added product.

Background Type 2 diabetes (T2D) is an interminable illness that makes many types of genetic dysfunction in the human body, particularly to the nerves, veins, kidneys, liver and uterus. T2D existence in a longer period of time may create the risk of building some comorbidities, however the indication of this risk is inadequately comprehended. To address this issue, we studied the transcriptomic data to recognize the link between T2D and its major comorbidities. Methods We developed a quantitative model to investigate the genetic links between T2D and its significant comorbidities. We analyzed gene expression omnibus (GEO) microarray data from T2D, liver cancer (LC), endometrial cancer (EC), xanthoma (Xa), myocardial infarction (MI), embolic stroke (ES), kidney failure (KF), xerostomia (Xe) and control datasets. We constructed gene-disease association networks (GDN), identified signaling and ontological pathways, formed protein-protein interaction (PPI) network employing neighborhood-based benchmarking and multilayer network topology. Results We observed, T2D shared 22, 15, 18, 21, 12, 14 and 13 differentially expressed genes (DEGs) with LC, EC, Xa, MI, ES, KF, and Xe respectively. DEG investigation, signaling and ontological pathways, and PPI network suggest significant links between T2D and the advancement of LC, EC, Xa, MI, ES, KF, and Xe. Conclusions Our systematic approach to identify the genetic links of T2D with the progression of LC, EC, Xa, MI, ES, KF, and Xe by understanding the causal influences of T2D may be helpful to develop therapeutic strategies for T2D and those comorbidities. This study will also be useful to predict comorbidities occurrence and build human awareness against the dangerous effects of T2D.

Noble metal nanoparticles have been widely employed for catalysis owing to their remarkable ability to reduce the activation energy of certain reactions. In this work, we followed a bio-inspired strategy to fabricate two magnetic nanocatalysts comprised of gold (AuNPs) and silver (AgNPs) nanoparticles. Magnetic graphene oxide (MGO), synthesized by deposition of Fe3O4 nanoparticles on graphene oxide (GO), was used as the support material. Inspired by the adhesive property of marine mussel, polydopamine (PDA) was used as the organic linker for robust immobilization of AuNPs and AgNPs on MGO surface to produce MGO-PDA@Au and MGO-PDA@Ag, respectively. We employed a wide range of microscopic and spectroscopic techniques such as HRTEM, FESEM, EDS, XPS, XRD, FTIR etc. to characterize the catalytic nanomaterials. The catalytic performances of these as-fabricated catalysts were investigated by monitoring the reductions of methylene blue (MB) and 4-nitrophenol (4-NP) by NaBH4 as model reactions. Thermogravimetric analysis and magnetization tests were also done to study the thermal stability and magnetic properties of the nanocomposites. The reaction rate constants obtained for both nanocomposites were found to be higher than most of the similar investigations reported elsewhere. In addition, we proposed a comparison of the catalytic performances of gold and silver nanoparticles when immobilized on same supporting material. This comparison provides means to have better insights of the factors affecting the catalytic performances of AuNPs and AgNPs along with identifying their selectivity towards specific catalytic applications.

The industrial revolution in the 20th century led to the evolution of numerous anthropogenic pollutants. Biochar, solid residue obtained from the pyrolysis of naturally available biomass, has attracted the attention of researchers due to its ability to remove these pollutants through adsorption from water and soil backed by various physicochemical properties. In this chapter, adsorptive removal of the pollutants involved is summarized in terms of the mechanisms that control the remediation. Research on heavy metals, organic contaminants, nutrients, oxyanions, and toxic gases considering the precise chemistry of polluted media and the biochar employed has been conducted. Functional improvement of biochar as adsorbent upon further chemical functionalization or fabrication of biochar composite is also discussed, with a focus on these pollutants. Finally, current challenges in biochar adsorptive remediation and future research opportunities required to overcome those challenges have been compiled.

This study reports the antimicrobial activity and improved dyeing performance of cotton knitted fabric by depositing silver nanoparticles on the surface. The cotton fabric is first treated with caustic soda (NaOH) of three different concentrations to activate the hydroxyl groups on the cellulose surface and then the nanoparticles are introduced on fabric surface by direct reduction of silver nitrate salt using ascorbic acid. The presence of silver nanoparticles on the fabric surface is clearly observed by scanning electron micrograph. The elementary analysis is done by energy dispersive spectroscopy and the chemical interaction of cotton fibre with nano silver is characterized by Fourier transform infrared spectrum. In this work, the antimicrobial activity on Ag deposited sample is investigated by quantitative analysis against both Gram positive (S. aureus) and Gram negative (E. coli) bacteria. Results shows a significant antimicrobial activity such as more than 90% bacterial reduction of both Gram positive and Gram negative bacteria are inhibited. The fabric sample is dyed with 2% direct dye and consequently the result shows very good performance in dye exhaustion, colour strength and fastness property. For instance, the incorporation of Ag nanoparticles increases 7% of dyestuff exhaustion and 15% of colour strength of the fabric. However, Ag nanoparticles deposited fabric loses its strength slightly due to the pretreatment using NaOH for the functionalization of cotton.

A new chelating resin was synthesized by modification of Amberlite XAD-4 resin with 1,8-diaminonaphthalene through an azo linkage ( N N ). The synthesized resin was characterized by scanning electron microscope, Fourier transform infrared spectroscope, elemental analysis and thermogravimetric analysis. It was applied to preconcentrate and separate Cu(II), Cd(II) and Pb(II) ions, which were determined subsequently by graphite furnace atomic absorption spectrometry. Various physico-chemical parameters that influence the quantitative preconcentration and recovery of the metals were optimized by both static and dynamic techniques. Among them, optimum pH was in the range 6–7. 2.0 M HNO 3 was selected as eluent. Optimum flow rates of sample and the eluent were found to be 2 and 4 mL min −1 , respectively. Preconcentration factors were 220 for Cu(II) and Cd(II) and 240 for Pb(II), sorption half times ( t 1/2 ) were 5 min for Cu(II) and Cd(II) and 6 min for Pb(II), respectively. The Langmuir, Freundlich and Temkin adsorption isotherms were also studied in detail. The procedure was validated by analysis of a certified reference material (A-11, powder milk). The new method was employed to estimate the metal ion concentrations quantitatively from dairy cow’s milk collected from dairy farm, Savar, Dhaka, Bangladesh.

A polyacrylic acid (PAA) functionalized magnetic Fe3O4 nanoparticle-graphene oxide nanocomposite (PAA/MGO) was synthesized by a facile method. The structure and surface properties of MGO and PAA/MGO composites were characterized by infrared (IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA) and zeta potential measurements. The adsorption of a model dye pollutant, methylene blue (MB), on MGO and PAA/MGO was investigated in batch tests. The functionalization of PAA to MGO significantly enhances the maximum adsorption capacity of MB (at pH = 7) from ∼70 mg g−1 (on MGO) to ∼291 mg g−1 (PAA/MGO). The adsorption of MB on MGO and PAA/MGO was mainly driven by the electrostatic attraction between positively charged MB molecules and negatively charged nanocomposite surfaces, and the higher adsorption capacity of PAA/MGO is mainly attributed to the functionalization of PAA and its higher content of charged carboxyl groups than MGO. The adsorption capacity of MB on both MGO and PAA/MGO adsorbents also increases with increasing solution pH from 3 to 11, due to enhanced electrostatic attraction at high pH conditions. The limited adsorption capacity of MB on MGO and PAA/MGO at pH 3, when electrostatic attraction is almost negligible, indicates that π–π interaction between the GO surface and MB also plays a role in the adsorption process. The PAA/MGO shows a rapid adsorption rate and high adsorption capacity of MB with magnetic properties for easy separation and excellent recyclability, which endows the nanocomposite with great potential for the removal of cationic organic pollutants in wastewater treatment.

We have monitored the interactions of DNA strands immobilized on silica at the buried solid/liquid interface using vibrational sum frequency generation. We find that the nucleobases exhibit net order even prior to hybridization for immobilized single strands. Moreover, varying the temperature of the hybridized samples leads to spectral changes from the thymine nucleobases that are consistent with duplex dissociation.