Anticonvulsant activity of furanocoumarins and the essential oil obtained from the fruits of Heracleum crenatifolium

The anticonvulsant activity of furanocoumarins, coumarin mixture and the essential oil obtained from the fruits of Heracleum crenatifolium was examined against maximal electroshock (MES)-induced seizures in mice. Bergapten showed significant anticonvulsant activity. The furanocoumarins isolated from the fruits of the plant were identified using thin-layer chromatography, melting points and spectroscopic methods (IR, MS, ¹H NMR) as isobergapten (1), pimpinellin (2), bergapten (3), isopimpinellin (4), sphondin (5) and byak-angelicol (6). The essential oil content of the fruits were found as 5.5%. Twenty-two compounds representing 99.3% of the essential oil obtained from the fruits of H. crenatifolium were determined and the major components were identified as octanol and octyl acetate (3.1% and 88.4% respectively) by GC and GC–MS.     

Methodological reviews and analyses on the emerging research trends and progresses of thermoelectric generators

Thermoelectric generator is among the earliest initiated electricity‐harvesting methods. It is a very potential power harvester that can convert wasteful thermal energy into electricity. However, it often suffers from low energy conversion rate due to its inconsistent heat source, inefficient thermoelectric material (or thermoelement) performance, and incompetent structural issues. Progressively for the first time, detailed methodological surveys and analyses are made for bulk, thick, and thin films in this review. This is in order to accommodate better insights and comprehensions on the emerging trends and progresses of thermoelectric generators from 1989 to 2017. The research interests in thermoelectric generators have started back in 1989, and have continuously experienced emerging progresses in the number of studies over the last years. The methodological reviews and analyses of thermoelectric generator showed that almost 46.6% of bulk and 46.1% of thick and thin film research works, respectively, are actively progressed in 2014 to 2017. Nearly 86.2% of bulk and 44.1% of thick and thin film thermoelectric generators are realizing in between 0.001 and 4 μW cm^?2 K^?2, while 43.1% of thick and thin films are earning among 10^?6 to 0.001 μW cm^?2 K^?2. The highest achievement made until now is 2.5 W cm^?2 at a temperature difference of 140 K and thermoelectric efficiency factor of 127.55 μW cm^?2 K^?2. This achievement remarked positive elevation for the field and interest in thermoelectric power generation. Consecutively, the research trends of fundamental devices' structure, thermoelement, fabrication, substrate, and heat source characteristics are analyzed too, along with the desired improvement highlights for the applications of thermoelectric generators.     

Chemically modified guar gum and ethyl acrylate composite as a new corrosion inhibitor for reduction in hydrogen evolution and tubular steel corrosion protection in acidic environment

The paper deals with the synthesis of Guar gum and ethyl acrylate (GG-EEA) composite. The synthesized natural polysaccharide composite was used as a corrosion inhibitor to reduce hydrogen evolution and P110 steel corrosion protection in 15% HCl (Hydrochloric acid). The primary corrosion techniques like weight loss, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) was used to analyze the corrosion inhibition process. The PDP proposed that GG-EEA composite is a mixed-type corrosion inhibitor and inhibits corrosion by blocking the active sites presenting over the metal surface. The corrosion inhibition performance of GG alone is 77.5%, and that of GG-EEA is 92.3% at 500 mg/L. The adsorption of GG-EEA onto P110 steel is spontaneous and mixed type, i.e., both physical and chemical. The conformation of GG-EEA molecule adsorption was done using a scanning electron microscope (SEM), Energy dispersive x-ray spectroscopy (EDX), Atomic force microscopy (AFM), and X-ray photoelectron spectroscopy studies. Density functional theory (DFT) analysis was done to explore the active sites over the inhibitor in metal-inhibitor interaction. Molecular dynamic simulation (MD) simulations study reveals that GG-EEA has more adsorption capacity than GG alone.     

An overview of heavy metal removal from wastewater using magnetotactic bacteria

Considering the increase in water contamination by heavy metal discharge, water quality experts are focusing on innovative future technologies for wastewater treatment. There are a number of physical, chemical and biological processes for acquiring high‐quality effluents; however, these treatment technologies have shown some limitations regarding their specific pollutant removal efficiencies, vulnerability to environmental pollutants, higher cost and energy requirements, excessive sludge volume and toxicity issues. Therefore, this review/concept paper focuses on the application of magnetotactic bacteria (MTB) in the removal of heavy metal from wastewater and also proposes a model application of MTB‐based treatment process. The unique property of the MTB is to move along the periphery of the applied external magnetic fields due to nano sized magnetosomes (MS). MS are basically the biomineral crystals of either magnetite (Fe₃O₄) or greigite (Fe₃S₄) with a size range of 30–120 nm. Moreover, challenging aspects concerning MTB employment in the removal of heavy metal from wastewater also are discussed in detail for the consideration of experts who are involved in the development of new treatment technologies or for retrofications of existing processes. © 2018 Society of Chemical Industry     

Effect of a Staphylococcus epidermidis-extracted slime factor on human natural killer cell activity

A slime factor produced by Staphylococcus epidermidis was a complex glycoconjugate extracted by the phenol extraction method. The potential stimulatory or inhibitory capacity of the phenol-extracted slime (PES) was tested on human natural killer cell cytotoxic activity. Various concentrations of the PES preparation were incubated with the effector cells 30 min before and during the assay period. The PES factor inhibited natural killer cell cytotoxic activity at a concentration of 250 micrograms/ml and at higher concentrations (p < 0.05). The inhibition of natural killer cell cytotoxic activity may probably be related to the complex composition of the slime substance.     

Call setup time standards

Call setup time will be important in the future due to the new ways in which customers will use the network. This study presents two models to estimate call setup time. One model for multi frequency (MF) and the other for common channel signalling (CCS).     

Endometrial pattern in diethylstilboestrol-exposed women undergoing in-vitro fertilization may be the most significant predictor of pregnancy outcome

The objective of this study was to compare prospectively pregnancy outcome as it is related to ultrasonic endometrial echo pattern in women exposed to diethylstilboestrol (DES) in utero by their mother's consumption with women not exposed to DES, all of whom were undergoing in-vitro fertilization (IVF). Pregnancy outcome relative to endometrial thickness and pattern was evaluated in 540 cycles of IVF including DES (n = 50) and non-DES-exposed (n = 490) women. Endometrial patterns were designated as p1 = solid; p2 = ring; and p3 = intermediate. DES patients exhibited p1 more often than the majority of the non-DES-exposed group. There was no significant difference in endometrial thickness among the cycles where p1 was noted when comparing the DES (10.3 mm) with the non-DES-exposed (10.7 mm) groups. Notably, within the group exhibiting p1, no pregnancies occurred in the 18 cycles of DES-exposed women compared with a 39.2% clinical pregnancy and 36.5% delivery rate in the non-DES-exposed controls (P < 0.0001 and P = 0.008 respectively). Pregnancy rates were not significantly different in the cycles where the other endometrial patterns were found when comparing the two groups. The impact of uterine shape on pregnancy outcome was also investigated. A T-shaped uterine configuration was noted in 11 out of 18 (61.1%) cycles of DES-exposed women with pattern p1 compared with nine out of 23 (39.1%) with pattern p2. Of cycles where a T-shaped uterus was demonstrated, none out of 11 (0%) with pattern p1 compared with four out of nine (44.4%) with pattern p2 resulted in pregnancy (P = 0.026). These data suggest that endometrial pattern is one of the most significant variables for pregnancy outcome in DES-exposed women undergoing IVF.     

Are RNGs Achilles’ Heel of RFID Security and Privacy Protocols?

Security and privacy concerns have been growing with the increased utilisation of RFID technology in our daily lives. To mitigate these issues, numerous privacy-friendly authentication protocols have been published in the last decade. Random number generators (RNGs) are necessarily used in RFID tags to provide security and privacy. However, low-end RNGs can be the weakest point in a protocol scheme and using them might undesirably cause severe security and privacy problems. On the other hand, having a secure RNG with large entropy might be a trade-off between security and cost for low-cost RFID tags. Furthermore, RNGs used in low-cost RFID tags might not work properly in time. Therefore, we claim that the vulnerability of using an RNG deeply influences the security and privacy level of the RFID system. To the best of our knowledge, this concern has not been considered in the RFID literature. Motivated by this need, in this study, we first revisit Vaudenay’s privacy model which combines the early models and presents a new mature privacy model with different adversary classes. Then, we extend the model by introducing RANDOMEYE privacy, which allows analyzing the security of RNGs in RFID protocols. We further apply our extended model to two existing RFID schemes.