Change in charge carrier dynamics by incorporating ionic liquid into poly ethylene oxide–based sodium acetate polymer electrolytes

Poly (ethylene oxide) based sodium ion conducting solid polymer electrolytes films (salt NaCH3COO) with varying amounts of an ionic liquid, 1-ethyl 3-methylimidazolium thiocyante were prepared by solution-cast method. All the prepared samples were characterized in detail for their ion transport characteristics at room temperature and temperature dependent behavior as well using electrochemical impedance spectroscopy. The measurement of ionic conductivity shows the many fold enhancement due the incorporation of ionic liquid in the polymer electrolyte matrix. The charge carrier density and mobility of charge carriers has been calculated and used for explaining the conductivity variations in these films. The increase in conductivity has been explained in terms of plasticization effect of ionic liquid and number of charge carriers per unit volume of electrolyte.

Trans Fatty Acid Analysis of Frying Oil Using ATR-FTIR Spectroscopy: A Study on Indian Traditional Snack Foods

Background: Trans Fatty Acid (TFA) content in oil is an important quality parameter due to its adverse health effect. This study was aimed to examine the TFA content in the frying oil used by street food vendors in India for two traditional snack foods. Methods: Totally, 143 oil samples were collected at different frying times (0, 2, and 4 h) from five different vendors for Samosa and Jalebi. TFA levels of the oil samples were analyzed by Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATRFTIR). Statistical analyses were carried out using SPSS software version 23.0. Results: ATR-FTIR spectra exhibited an increase in peak intensity at 966 cm-1 with different frying time in both frying oil samples, indicating the formation of TFA. The TFA content in oils fried at 4 h was significantly higher than the ones at 0 and 2 intervals. It was found that 3 out of 74 (4%) Samosa fried oils and 12 out of 69 (17.4%) Jalebi fried oils were over the maximum allowed regulatory limit of TFA (5%). Jalebi fried oils had significantly higher TFA content than Samosa fried oils. Conclusion: The increase in frying time decreased the peroxide values and increased saturated fatty acids and TFA values of oils used for both food items. The local vendors and consumers should be educated by national authorities regarding health risk of TFA in street fried snacks.

Electrical, thermal, and dielectric studies of ionic liquid-based polymer electrolyte for photoelectrochemical device

In this work, solution cast method was adapted for the preparation of 1-ethyl-3-methylimidazolium dicyanamide (EMImDCN)-doped solid polymer electrolyte. Optimum composition of polymer electrolyte (polyethylene oxide + sodium iodide) was treated as the host polymer. The ionic conductivity was further enhanced by adding low-viscosity ionic liquid (IL) EMImDCN. Electrical, thermal, dielectric, and photoelectrochemical properties of polymer host and IL-doped solid polymer electrolyte (ILDPE) are presented in detail. An electrochemical device, that is, dye-sensitized solar cell was fabricated using maximum conducting ILDPE film, which shows short-circuit current density of 0.118 mA/cm2, open-circuit voltage of 0.71 V, and overall efficiency of 0.061% at 1 sun condition.

Low-viscosity ionic liquid–doped solid polymer electrolytes

Polymer electrolyte films based on poly(ethylene oxide) doped with salt sodium nitrate and ionic liquid (IL; 1-ethyl 3-methylimidazolium thiocyanate) have been prepared and characterized by differential scanning calorimetry (DSC) and impedance spectroscopy. The relative percentage of crystallinity of polymer electrolytes has been calculated by using DSC thermograms and electrical properties by using impedance spectroscopy. The incorporation of IL in polymer matrix increases the conductivity of polymer electrolyte. The maximum value of ionic conductivity of polymer electrolyte is found to be 1.93 × 10−4 S m−1 with 9 wt% IL.

PVDF-HFP and 1-ethyl-3-methylimidazolium thiocyanate–doped polymer electrolyte for efficient supercapacitors

The sole aim of the present article is to develop an ionic liquid (IL)-doped solid polymer electrolyte for an electrochemical double-layer capacitor (EDLC). A solution cast technique was adopted to develop a solid polymer electrolyte of poly (vinylidene fluoride-co-hexafluoropropylene) as host polymer and low-viscosity IL (1-ethyl-3-methylimidazolium thiocyanate) as dopant. Electrochemical impedance spectroscopy measurement showed a six orders of magnitude enhancement in conductivity ( σ) by IL doping. A linear sweep voltammetric investigation of the electrolyte films exhibited a good electrochemical stability window of 3.6 V. Polarized optical microscopy of the synthesized films revealed a reduction in crystallinity by IL doping. Infrared spectroscopy further affirms the composite nature of the film. The maximum conductivity value of 2.65 mS/cm is obtained for 80% of the ionic-doped system. Using maximum conductivity film and porous carbon-based electrodes, we have developed EDLCs that show a specific capacitance value of 2.36 F/g.

Electrical and structural properties of multi-walled carbon nanotube–doped polymer electrolyte for photo electrochemical device

The present investigation deals with the preparation of multi-walled carbon nanotube (MWCNT)-doped plasticized polymer electrolyte. The nanocomposite has been prepared using solution casting method. Complex impedance spectroscopy study revealed the utmost room temperature conductivity of 5.6 × 10−4 S/cm when optimized plasticized polymer electrolyte (poly(ethyl methacrylate)+30% sodium iodide+60% ethylene carbonate) was doped with 7% MWCNT. Temperature dependence of conductivity showed Arrhenius behavior. The surface morphology and crystalline–amorphous deviation of the composite was observed using scanning electron microscope. Perfect complexation of various components of the composite was confirmed from Fourier-transform infrared spectroscopy and X-ray diffraction (XRD) data. The transference number measurement was done to calculate the proportionate amount of ionic and electronic conductivity. A dye sensitized solar cell has been fabricated using maximum ionic conductivity of solid polymer electrolyte and its electrical parameters measured at 1 sun condition.

Most commercial insulin assays fail to detect recombinant insulin analogues

Insulin assays are utilized in various clinical scenarios, including the assessment of insulin therapy compliance or of suspected insulin overdose. In an interpretative exercise carried out by UK National External Quality Assessment Service (NEQAS), serum sent to the participating laboratories was spiked with 30 pmol/L of the short-acting insulin analogue Human Actrapid. Only two out of 24 participant laboratories had sufficient assay cross-reactivity with Actrapid to interpret the results as suggestive of insulin administration. The development of specific insulin assays has led to deterioration in the ability to detect non-compliance or overdose with recombinant insulin treatment. Clinicians should be aware of this significant limitation, which could lead to misdiagnosis.

Liquorice and soy sauce, a life-saving concoction in a patient with Addison's disease

Addison's disease is a relatively common disorder to endocrinologists, but is rare and potentially fatal when presenting acutely. Treatment now involves replacement of glucocorticoids and mineralocorticoids with synthetic compounds, although historically patients took common salt and plant-based preparations. We describe the case of a 42-year-old woman who self-treated undiagnosed Addison's disease for several years with soy sauce and liquorice sticks. She presented with a four-week history of decreased energy, malaise and postural dizziness. Our patient described an unusual diet of liquorice sticks and soy sauce, consuming around 46 g of salt per week. There was a family history of Type 1 diabetes mellitus. Physical examination was unremarkable, although subsequent investigation confirmed Addison's disease. Liquorice provided glycyrrhizic acid and glycyrrhetinic acid, which act on 11-beta hydroxysteroid dehydrogenase enzymes. In this case, the net effect was potentiation of glucocorticoid action on renal mineralocorticoid receptors in the context of failing adrenocortical steroid production. The case highlights the importance of taking a dietary history to aid diagnosis.

Shear Thickening Behaviour of Composite Propellant Suspension under Oscillatory Shear

Composite propellant suspensions consist of highly filled polymeric system wherein solid particles of different sizes and shapes are dispersed in a polymeric matrix. The rheological behaviour of a propellant suspension is characterised by viscoplasticity and shear rate and time dependant viscosity. The behaviour of composite propellant suspension has been studied under amplitude sweep test where tests were performed by continuously varying strain amplitude (strain in %, γ) by keeping the frequency and temperature constant and results are plotted in terms of log γ (strain amplitude) vs logGʹ and logGʺ (Storage modulus and loss modulus, respectively). It is clear from amplitude sweep test that dynamic moduli and complex viscosity show marked increase at critical strain amplitude after a plateau region, infering a shear thickening behaviour.

Synthesis and properties of polyaniline, poly(o-anisidine), and poly[aniline-co-(o-anisidine)] using potassium iodate oxidizing agent

Polyaniline (PANI), poly( o-anisidine), and poly[aniline-co-( o-anisidine)] were synthesized by chemical oxidative polymerization with potassium iodate as an oxidizing agent in a hydrochloric acid (HCl) medium. The self-doped, doped, and undoped forms of these polymers were characterized by infrared spectroscopy, ultraviolet–visible spectroscopy, and the conductivity method. The observed decrease in the conductivity of the copolymer and poly( o-anisidine) with respect to PANI was attributed to the incorporation of methoxy moieties into the PANI chain. The homopolymer attained conductivity in the range of 3.75 × 10−3 to 7.40 S cm−1 after doping with HCl. The conductivity of the undoped form of poly[aniline-co-( o-anisidine)] and poly( o-anisidine) was observed to be lower than 10−5 S cm−1. The conductivity of the polymer sample decreased in the following order: PANI → poly[aniline-co-( o-anisidine)] → poly( o-anisidine). The undoped form of poly[aniline-co-( o-anisidine)] had good solubility in common organic solvents.

Mutation at codon 442 in the rpoB gene of Mycobacterium leprae does not confer resistance to rifampicin

BACKGROUND

Rifampicin is the major drug in the treatment of leprosy. The rifampicin resistance of Mycobacterium leprae results from a mutation in the rpoB gene, encoding the β subunit of RNA polymerase. As M. leprae is a non-cultivable organism observation of its growth using mouse food-pad (MFP) is the only Gold Standard assay used for confirmation of "in-vivo" drug resistance.

OBJECTIVE

Any mutation at molecular level has to be verified by MFP assay for final confirmation of drug resistance in leprosy.

MATERIAL AND METHODS

In the present study, M. leprae strains showing a mutation only at codon 442 Gln-His and along with mutation either at codon 424 Val-Gly or at 438 Gln-Val within the Rifampicin Resistance Determining Region (RRDR) confirmed by DNA sequencing and by high resolution melting (HRM) analysis were subjected for its growth in MFP.

RESULT AND CONCLUSION

The M. leprae strain having the new mutation at codon 442 Gln-His was found to be sensitive to all the three drugs and strains having additional mutations at 424 Val-Gly and 438 Gln-Val were conferring resistance with Multi drug therapy (MDT) in MFP. These results indicate that MFP is the gold standard method for confirming the mutations detected by molecular techniques.

Vitamin D receptor expression levels determine the severity and complexity of disease progression among leprosy reaction patients

We studied the roles of vitamin D and its receptor, VDR, in the progression of leprosy. The majority of individuals with leprosy from Kolkata, India, with a type 1 or type 2 reaction have low levels of vitamin D₃ in serum samples. Interestingly, individuals with a type 2 reaction associated with neuritis/erythema nodosum leprosum had very low VDR mRNA expression levels, ranging from 5% to 10%, compared to that of healthy control subjects; these patients also had a high bacilli index, ranging from 3+ to 5+. This is the first report to indicate that VDR expression levels may determine the complexity and severity of the progression of leprosy.

Synthesis, characterization, and dye-sensitized solar cell fabrication using solid biopolymer electrolyte membranes

Solid biopolymer-based electrolytes have been synthesized and characterized. Potassium iodide (KI) and iodine have been added in a biopolymer (sago palm) matrix to develop solid polymer electrolyte. Relationships between electrical and ionic transport parameters have been studied in detail, and the mechanism for ion transport has been proposed. Impedance spectroscopy reveals a significant enhancement in ionic conductivity by salt doping and the conductivity maxima was obtained at 50 wt% of KI concentration and also the system displays Arrhenius behavior. Dielectric phenomenon, mobility, charge carrier density, and diffusion coefficient also supports the conductivity data. Fourier transform infrared spectroscopy confirms the formation of a complex structure, while X-ray diffraction and optical microscopy affirms the complex structure as well as a reduction of crystallinity in the biopolymer electrolyte by salt doping. A dye-sensitized solar cell fabricated using fluorine-doped tin oxide–titanium dioxide (N3 dye)/maximum conducting electrolyte showed the short-circuit current density of 2.91 × 10−4 A cm−2, open-circuit voltage of 0.58 V, and efficiency of 0.57% at 1 sun condition.

Increased drug resistance is associated with reduced glucose levels and an enhanced glycolysis phenotype

BACKGROUND AND PURPOSE

The testing of anticancer compounds in vitro is usually performed in hyperglycaemic cell cultures, although many tumours and their in vivo microenvironments are hypoglycaemic. Here, we have assessed, in cultures of tumour cells, the effects of reduced glucose levels on resistance to anticancer drugs and investigated the underlying cellular mechanisms.

EXPERIMENTAL APPROACH

PIK3CA mutant (AGS, HGC27), and wild-type (MKN45, NUGC4) gastric cancer cells were cultured in high-glucose (HG, 25 mM) or low-glucose (LG, 5 mM) media and tested for sensitivity to two cytotoxic compounds, 5-fluorouracil (5-FU) and carboplatin, the PI3K/mTOR inhibitor, PI103 and the mTOR inhibitor, Ku-0063794.

KEY RESULTS

All cells had increased resistance to 5-FU and carboplatin when cultured in LG compared with HG conditions despite having similar growth and cell cycle characteristics. On treatment with PI103 or Ku-0063794, only the PIK3CA mutant cells displayed increased resistance in LG conditions. The PIK3CA mutant LG cells had selectively increased p-mTOR, p-S6, p-4EBP1, GLUT1 and lactate production, and reduced reactive oxygen species, consistent with increased glycolysis. Combination analysis indicated PI103 and Ku-0063794 were synergistic in PIK3CA mutant LG cells only. Synergism was accompanied by reduced mTOR signalling and increased autophagy.

CONCLUSIONS AND IMPLICATIONS

Hypoglycaemia increased resistance to cytotoxic agents, especially in tumour cells with a high dependence on glycolysis. Dual inhibition of the PI3K/mTOR pathway may be able to attenuate such hypoglycaemia-associated resistance.

Electronic and optical properties of pristine and boron–nitrogen doped graphyne nanotubes

The band gaps and optical responses of graphyne nanotubes can be engineered through the selection of the BN doping site and the chirality.

A deterministic thermostat for controlling temperature using all degrees of freedom

We propose a new thermostat that uses all the phase space variables for controlling temperature and thus differs from the existing thermostats that control either the kinetic (e.g., Nose Hoover) or the configurational (e.g., Braga Travis) degrees of freedom. Our thermostat is a special case of the set of equations proposed by Kusnezov et al. [Ann. Phys. 204, 155 (1990)] and is derived using the extended system method. We show that it generates a canonical phase-space distribution. The performance of the thermostat is compared with those of Nose-Hoover kinetic thermostat and Braga-Travis configurational thermostat for a system (i) in thermal equilibrium, (ii) subjected to sudden temperature changes, and (iii) in steady state non-equilibrium under thermal conduction. We observe that all three thermostats perform similarly for systems in equilibrium. However, our thermostat performs the best in the thermal conduction problem by generating a consistent temperature profile across the conduction length. We expect this thermostat to be useful in other non-equilibrium scenarios as well.

Vitamin-D supplementation in prediabetes reduced progression to type 2 diabetes and was associated with decreased insulin resistance and systemic inflammation: an open label randomized prospective study from Eastern India

Vitamin-D supplementation in vitamin-D insufficient/deficient prediabetes individuals is associated with significantly lower progression to diabetes (6/55 vs. 13/49; p=0.04) and higher reversal to normoglycemia (23/55 vs. 10/49; p=0.02), associated with decreased insulin resistance and systemic inflammation (TNFα and IL6). Baseline vitamin-D and 2h blood glucose independently predicted progression to diabetes.

Development of an eco-friendly method to convert life expired composite propellant into liquid fertilizer

Large quantity of composite propellants is produced as waste due to life expiry of missiles/rejection of propellant lots during manufacturing. The environmental protection agency does not allow the hazardous materials for open burning/open detonation. Therefore, a systematic study has been carried out to develop a method for the disposal of composite propellant into liquid fertilizer without affecting the environment. In this study, propellant compositions were digested in dilute nitric acid followed by neutralization with 5M KOH solution to get precipitated out aluminium as aluminium hydroxide and finally the obtained liquid was treated with orthophosphoric acid for further neutralization. The liquid fertilizer, thus, obtained was characterized for nitrate and phosphate content using ion chromatography while ICP-AES was used for the estimation of potassium, aluminium and other noxious metallic elements such as Pb, Cd, As, Cr, Cu, Ni and Zn. The analyses data indicate that liquid fertilizer is free from aluminium and noxious metallic elements while ratio of nitrogen, phosphorous and potassium are close to the Indian NPK value.

Detection of mycoplasma contamination in cell substrates using reverse transcription-PCR assays

AIMS

To assess the limit of detection (LOD) and the feasibility of 16S rRNA-based reverse transcription-PCR (RT-PCR) assays for advanced detection of mycoplasma contamination in cell substrates.

MATERIALS AND METHODS

The RT-PCR approach is based on detecting the 16S rRNA molecules that, in contrast to genomic bacterial DNA, are represented by multiple copies in mycoplasma cell. The number of 16S rRNA molecules in mycoplasma cells of five species i.e. Mycoplasma arginini, Myc. fermentans, Myc. hyorhinis, Myc. orale and Acholeplasma laidlawii, all known to be frequent cell line contaminants in industrial and research laboratories, was measured using molecular methods. The results of two independently prepared mycoplasma cultures harvested at the stationary phase of their growth showed that the 16S rRNA copy number per cell varied in the range from about 400 to 2000 copies, depending on species, but stayed close between different preparations of one species. The assessment of the LOD of the in-house 16S rRNA-based RT-PCR was performed using samples of MDCK cell culture spiked with different amounts of five aforementioned mycoplasma species. To minimize the bias in methods comparison, the LOD of the RT-PCR assay was expressed in terms of genome equivalents (GEs) and compared with that determined for highly optimized 16S rDNA-based mycoplasma testing methods previously described in scientific literature.

CONCLUSIONS

The results of the study showed that the in-house 16S rRNA-based RT-PCR assay was able to reliably detect the presence of less than one mycoplasma GE that is at least 10-fold higher of the LOD previously determined for well-optimized 16S rDNA-based assays developed and described by other researchers.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of the study showed that rapid RT-PCR methods based on the detection of bacterial 16S rRNA are able to expedite mycoplasma testing of cell cultures (1-2 days vs 28 days) and to ensure the limits of detection comparable to that of currently used culture-based mycoplasma testing methods.

Studies on the effect of plasticiser and addition of toluene diisocyanate at different temperatures in composite propellant formulations

Different composite propellant mixtures have been prepared using ammonium perchlorate, aluminium powder and hydroxyl terminated polybutadiene by varying the percentage of plasticiser and addition of toluene diisocyanate at different temperatures, and studied their different properties such as viscosity build-up, mechanical and ballistic properties and sensitivity. The data on different plasticiser level indicate that on decreasing the plasticiser content, there is a significant enhancement in end of mix viscosity, tensile strength and modulus while elongation decreases drastically. The data on sensitivity of the studied mixtures reveal that on decreasing the percentage of plasticiser, the sensitivity increases, accordingly. Further, the data on the effect of addition of TDI at different temperatures (35-60 degrees C) infer that on increasing the addition temperature of TDI there is a decrease in end of mix viscosity i.e. 800Pas at 35 degrees C to 448Pas at 60 degrees C. Moreover, there is no effect on mechanical and ballistic properties on higher temperature addition of TDI was observed.

Adenosine deaminase estimation and multiplex polymerase chain reaction in diagnosis of extra-pulmonary tuberculosis

SETTING

Extra-pulmonary tuberculosis (EPTB), including mycobacteriosis, contributes 15-20% of all tuberculosis (TB) cases. The diagnosis of EPTB remains elusive because of the inadequate sensitivity of routine and conventional bacteriological methods for the detection of Mycobacterium tuberculosis and related organisms in clinical specimens such as cerebrospinal fluid (CSF), pleural fluid and peritoneal fluid.

OBJECTIVE

To develop a better diagnostic marker for EPTB.

DESIGN

In our study, 179 cases of EPTB were analysed for acid-fast bacilli (AFB) smear, adenosine deaminase activity (ADA) and multiplex polymerase chain reaction (PCR). Although estimation of ADA is helpful, its sensitivity and specificity varies widely. On the other hand, a multiplex PCR using amplicons such as IS6110, dnaJ gene and hsp65 genes has high sensitivity (60-88%) and specificity (81-100%).

RESULTS

On comparing AFB and ADA results with PCR, the PCR is clearly more effective than AFB (P < 0.001) and ADA estimation (P < 0.02) in CSF. The same result was observed with peritoneal fluid (P < 0.001 vs. P < 0.05) and pleural fluid (P < 0.001 and P < 0.05).

CONCLUSION

The study shows that multiplex PCR remains the best tool and is a much better marker for diagnosing EPTB.

Alteration of timing of secretion of vascular endothelial growth factors is responsible for progression of diabetic retinopathy

Diabetic retinopathy is one of the most common complications in diabetes mellitus due to persistent hyperglycaemia. Various biochemical mechanisms have been suggested to cause this complication. The authors' present study which included 100 patients of type-2 diabetes mellitus with different stages of diabetic retinopathy and without retinopathy shows that initiation of diabetic retinopathy is associated with increased anaerobic glycolysis and accelerated oxidative stress. Progression of this complication is guided by increased secretion of vascular endothelial growth factors. It is our assumption that increased secretion of vascular endothelial growth factors in early part of this disease e.g. before occurrence of morphological abnormality may modify this complication.

Primary tuberculosis of thyroid gland: a rare case report

Tuberculosis of the thyroid gland is a rare entity, and primary tuberculosis of thyroid is even uncommon. At one time, it was believed that thyroid gland is relatively immune to tuberculosis. There are about 200 cases of thyroid tuberculosis that had been reported in world literature. These include 156 cases reviewed by Goldfarb et al (Am J Med 1965;38:825) and 1 each by Crompton et al (Tubercle 1969;50:61-64), Johnson et al (Br J Surg 1973;60:668-669), Emry (J Laryngol Otol 1980;94:553-558), and Kukreja and Sharma ML (Ind J Surg 1982;44:190-192), and a histologic diagnosis by Das et al (Acta Cytol 1992;36:517-522) and Mondal and Patra (J Laryngol Otol 1995;109:36-38). Almost all cases had primary foci elsewhere in the body. Isolated tuberculosis of the thyroid gland is extremely rare, with few reported cases; when it does occur, it may prove difficult to diagnose (J Laryngol Otol 1980;94:553-558). Among the different manifestations of tuberculous thyroiditis, abscess of the thyroid appears to be the rarest and the most dangerous (Tubercle 1969;50:61-64). Sachs et al (Am J Med 1988;85:573-575) reported 4 cases of tuberculous thyroiditis that were diagnosed preoperatively, the rest of the cases were diagnosed either from surgical specimen or from autopsy. A case of primary tuberculosis of thyroid gland presenting as abscess and diagnosed preoperatively is reported here.

Waste explosives and other hazardous materials--hazard potential and remedial measures: an overview

A large amount of energetic materials including propellants, high explosives, pyrotechnics are subjected to disposal either due to expiry of their useful life or rejection in the manufacturing process. The environmental regulations do not allow the hazardous materials for open burning / detonation in view of the health hazard involved in these operations. The present paper describes the hazard potential of energetic materials and associated hazardous chemicals. It also deals with global technological status for remedial measures of hazardous chemicals along with their merits and demerits.