789 research outputs found
Toxic compounds in honey
No full textThere is a wealth of information about the nutritional and medicinal properties of honey. However, honey may contain compounds that may lead to toxicity. A compound not naturally present in honey, named 5‐hydroxymethylfurfural (HMF), may be formed during the heating or preservation processes of honey. HMF has gained much interest, as it is commonly detected in honey samples, especially samples that have been stored for a long time. HMF is a compound that may be mutagenic, carcinogenic and cytotoxic. It has also been reported that honey can be contaminated with heavy metals such as lead, arsenic, mercury and cadmium. Honey produced from the nectar of Rhododendron ponticum contains alkaloids that can be poisonous to humans, while honey collected from Andromeda flowers contains grayanotoxins, which can cause paralysis of limbs in humans and eventually leads to death. In addition, Melicope ternata and Coriaria arborea from New Zealand produce toxic honey that can be fatal. There are reports that honey is not safe to be consumed when it is collected from Datura plants (from Mexico and Hungary), belladonna flowers and Hyoscamus niger plants (from Hungary), Serjania lethalis (from Brazil), Gelsemium sempervirens (from the American Southwest), Kalmia latifolia, Tripetalia paniculata and Ledum palustre. Although the symptoms of poisoning due to honey consumption may differ depending on the source of toxins, most common symptoms generally include dizziness, nausea, vomiting, convulsions, headache, palpitations or even death. It has been suggested that honey should not be considered a completely safe food. Copyright © 2013 John Wiley & Sons, Ltd
The effect of surface treatments and graphene-based modifications on mechanical properties of natural jute fiber composites: A review
Full text linkNatural fiber reinforced composites (FRC) are of great interests, because of their biodegradability, recyclability, and environmental benefits over synthetic FRC. Natural jute FRC could provide an environmentally sustainable, light weight, and cost-effective alternative to synthetic FRC. However, the application of natural jute FRC is limited because of their poor mechanical and interfacial properties. Graphene and its derivatives could potentially be applied to modify jute fiber surface for manufacturing natural FRC with excellent mechanical properties, and lower environmental impacts. Here, we review the physical and chemical treatments, and graphene-based modifications of jute fibers, and their effect on mechanical properties of jute FRC. We introduce jute fiber structure, chemical compositions, and their potential applications first. We then provide an overview of various surface treatments used to improve mechanical properties of jute FRC. We discuss and compare various graphene derivative-based surface modifications of jute fibers, and their impact on the performance of FRC. Finally, we provide our future perspective on graphene-based jute fibers research to enable next generation strong and sustainable FRC for high performance engineering applications without conferring environmental problems
Suppl_Material - Pharmacokinetics and Bioavailability Study of a Prednisolone Tablet as a Single Oral Dose in Bangladeshi Healthy Volunteers
No full textSuppl_Material for Pharmacokinetics and Bioavailability Study of a Prednisolone Tablet as a Single Oral Dose in Bangladeshi Healthy Volunteers by Tafsir Bashar, Mohd Nazmul Hasan Apu, Md Shaki Mostaid, Md Saiful Islam, and Abul Hasnat in Dose-Response</p
Smart electronic textile‐based wearable supercapacitors
Full text linkElectronic textiles (e-textiles) have drawn significant attention from the scientific and engineering community as lightweight and comfortable next-generation wearable devices due to their ability to interface with the human body, and continuously monitor, collect, and communicate various physiological parameters. However, one of the major challenges for the commercialization and further growth of e-textiles is the lack of compatible power supply units. Thin and flexible supercapacitors (SCs), among various energy storage systems, are gaining consideration due to their salient features including excellent lifetime, lightweight, and high-power density. Textile-based SCs are thus an exciting energy storage solution to power smart gadgets integrated into clothing. Here, materials, fabrications, and characterization strategies for textile-based SCs are reviewed. The recent progress of textile-based SCs is then summarized in terms of their electrochemical performances, followed by the discussion on key parameters for their wearable electronics applications, including washability, flexibility, and scalability. Finally, the perspectives on their research and technological prospects to facilitate an essential step towards moving from laboratory-based flexible and wearable SCs to industrial-scale mass production are presented
Scalable production of 2D material heterostructure textiles for high-performance wearable supercapacitors
Full text linkWearable electronic textiles (e-textiles) have emerged as a promising platform for seamless integration of electronic devices into everyday life, enabling nonintrusive monitoring of human health. However, the development of efficient, flexible, and scalable energy storage solutions remains a significant challenge for powering such devices. Here, we address this challenge by leveraging the distinct properties of two-dimensional (2D) material based heterostructures to enhance the performance of wearable textile supercapacitors. We report a highly scalable and controllable synthesis method for graphene and molybdenum disulfide (MoS2) through a microfluidization technique. Subsequently, we employ an ultrafast and industry-scale hierarchical deposition approach using a pad-dry method to fabricate 2D heterostructure based textiles with various configurations suitable for wearable e-textiles applications. Comparative analyses reveal the superior performance of wearable textile supercapacitors based on 2D material heterostructures, demonstrating excellent areal capacitance (∼105.08 mF cm-2), high power density (∼1604.274 μW cm-2) and energy density (∼58.377 μWh cm-2), and outstanding capacitive retention (∼100% after 1000 cycles). Our findings highlight the pivotal role of 2D material based heterostructures in addressing the challenges of performance and scalability in wearable energy storage devices, facilitating large-scale production of high-performance wearable supercapacitors
Metal-Organic Framework (MOF)-based smart e-textile supercapacitors
No full textWearable electronic textiles, also known as e-textiles, have surfaced as a promising means of seamless and unobstructed incorporation of electronic health monitoring gadgets into our daily routines. Yet, creating high-performance and flexible energy storage solutions still presents a notable hurdle in advancing these technologies. Nevertheless, creating efficient, adaptable, and expandable energy storage solutions continues to pose a noteworthy obstacle in powering these devices. This study demonstrates a facile strategy to design and fabricate MOF-based smart wearable e-textiles for all-solid-state textile supercapacitors. We report the fabrication of highly flexible and washable e-textiles by exploiting screen printing, pad-dry coating and inkjet print technology utilising a standalone MOF. The fabricated e-textiles were used as electrodes for an all-solid-state textile supercapacitor. The high areal capacitance of ~221.51 mF cm-2, ~359.4 mF cm-2 and ~353.5 mF cm-2 were achieved at a scan rate of 1 mVs-1 for screen print, pad-dry coating and inkjet printing technology respectively. With high energy densities of ~123.06 µWh cm−2 (screen print), ~199.66 µWh cm−2 (coating) and ~196.39 µWh cm−2 (inkjet print) and very high-power densities ~55 377.5 µW cm−2 (screen print) ~55 291.54 µW cm−2 (coating) ~54 385.38 µW cm−2 (inkjet print), the supercapacitors also showed outstanding capacitance retention (⁓97.4-97.9%) after 1 000 cycles. Our findings successfully demonstrate the potential of MOF-based smart textiles for wearable electronics applications, especially opening a new pathway for high-performance textile-based energy storage solutions.<br/
Prospect of phytoaccumulation of arsenic by Brassica juncea (L.) in Bangladesh
No full textThe phytoaccummulation of arsenic by Brassica juncea (L.) was investigated for varying concentrations selected within the range that is evident in Bangladeshi soil. B. juncea (Rai and BARI-11) was grown in the hydroponic media under greenhouse condition with different concentrations (0.5, 1.0, 15, 30, 50 and 100 ppm) of sodium arsenite. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) was used to analyze the data. Mapping of potential area of phytoaccumulation of arsenic by B. juncea was done using Geographic information system (GIS). Arsenic was detected at lower concentrations (0.5 and 1.0 ppm) only at root system of the plant. For higher concentrations (15, 30, and 50 ppm) arsenic was detected both in the root and shoot systems. The results suggested that at 15 and 50 ppm uptake was higher compared to 30 ppm. For 100 ppm of arsenic no plant growth was observed. In Bangladesh, where concentration of arsenic is at lower level and present only at rooting zone, B. juncea may be used for phytoaccumulation of arsenic keeping usual agronomic practices. However, for higher concentrations, B. juncea can be regarded as a good accumulator of arsenic where uptake of arsenic was up to 1% of total biomass of the plant.</p
Optical biosensing strategies for DNA methylation analysis
No full textDNA methylation is an epigenetic modification of DNA, where a methyl group is added at the fifth carbon of the cytosine base to form 5 methyl cytosine (5mC) without altering the DNA sequences. It plays important roles in regulating many cellular processes by modulating key genes expression. Alteration in DNA methylation patterns becomes particularly important in the aetiology of different diseases including cancers. Abnormal methylation pattern could contribute to the pathogenesis of cancer either by silencing key tumor suppressor genes or by activating oncogenes. Thus, DNA methylation biosensing can help in the better understanding of cancer prognosis and diagnosis and aid the development of therapies. Over the last few decades, a plethora of optical detection techniques have been developed for analyzing DNA methylation using fluorescence, Raman spectroscopy, surface plasmon resonance (SPR), electrochemiluminescence and colorimetric readouts. This paper aims to comprehensively review the optical strategies for DNA methylation detection. We also present an overview of the remaining challenges of optical strategies that still need to be focused along with the lesson learnt while working with these techniques
Physicochemical and Antioxidant Properties of Algerian Honey
No full textThe aim of the present study was to characterize the physical, biochemical and antioxidant properties of Algerian honey samples (n = 4). Physical parameters, such as pH, moisture content, electrical conductivity (EC), total dissolved solids (TDS), color intensity, total sugar and sucrose content were measured. Several biochemical and antioxidant tests were performed to determine the antioxidant properties of the honey samples. The mean pH was 3.84 ± 0.01, and moisture the content was 13.21 ± 0.16%. The mean EC was 0.636 ± 0.001, and the mean TDS was 316.92 ± 0.92. The mean color was 120.58 ± 0.64 mm Pfund, and the mean 5-hydroxymethylfurfural (HMF) content was 21.49 mg/kg. The mean total sugar and reducing sugar contents were 67.03 ± 0.68 g/mL and 64.72 ± 0.52 g/g, respectively. The mean sucrose content was 2.29 ± 0.65%. High mean values of phenolic (459.83 ± 1.92 mg gallic acid/kg), flavonoid (54.23 ± 0.62 mg catechin/kg), ascorbic acid (159.70 ± 0.78 mg/kg), AEAC (278.15 ± 4.34 mg/kg), protein (3381.83 ± 6.19 mg/kg) and proline (2131.47 ± 0.90) contents, as well as DPPH (39.57% ± 4.18) and FRAP activities [337.77 ± 1.01 µM Fe (II)/100 g], were also detected, indicating that Algerian honey has a high antioxidant potential. Strong positive correlations were found between flavonoid, proline and ascorbic acid contents and color intensity with DPPH and FRAP values. Thus, the present study revealed that Algerian honey is a good source of antioxidants
Inkjet‐printed 2D heterostructures for smart textile micro‐supercapacitors
No full textWearable electronic textiles (e-textiles) have emerged as promising healthcare solutions, offering point-of-care diagnostics while maintaining breathability, comfort, durability, and environmental stability with strong mechanical performance. However, the lack of thin and flexible power supplies hinders their practical adoption. In this regard, textile-based micro-energy storage devices present an appealing solution. Inkjet printing offers the capability to produce high-quality prints with sharp details and versatile substrate compatibility, making it an ideal choice for a wide array of printing applications. Here, the preparation of a range of inkjet-printable 2D material inks is reported for the fabrication of ultra-flexible and machine-washable textile micro-supercapacitors. Then 2D material heterostructures are proposed to enhance the performance of textile supercapacitors. This study reveals that a unique combination of highly conductive graphene with an insulator hexagonal boron nitride (h-BN) can enhance the areal capacitance of graphene-based textile supercapacitors by ≈82.48%. The heterostructure-based supercapacitors also demonstrate higher energy (≈18.06 µWh cm −2) and power densities (≈4333.33 µW cm −2) with excellent capacitance retention (≈95% after 1000 cycles). These findings on inkjet-printed heterostructure-based supercapacitors may herald a new era for the future application of high-performance micro-supercapacitors within textile-based wearable technology.</p
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