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The study was designed to document the phytodiversity and vegetation dynamics of Chour Valley, Hazara Division, Pakistan during 2018–19. Sum of 115 plant species belonged to 48 families were documented. The leading family was Rosaceae with 14 plant species followed by Asteraceae (11 species). The data were analyzed for classification through two way indicator species Analysis and ordination through CCA and DCA to find differences in directories of plants communities and their habitats kind. Five plants communities were identified including, Abies-Pinus-Rheum, Picea-Cyperus-Oxalis, Rumex-Urtica-Cyperus, Picea-Betula-Viburnum and Berberis-Clematis-Potentilla communities. It was observed that the distribution of species and community structure was directly correlated to altitude, slope aspect and soil characteristics. It was also noticed that forest in the study area are continuously degraded and will go in vanishing, until conservation and restoration measures are adopted in priority basis.

Natural products are known to control diabetes and its associated complications. Leaves of Hedera nepalensis are used to cure diabetes in the folklore system of medicines. The present study was designed to evaluate the in vivo antidiabetic and wound healing potentials of ethanol extract of Hedera nepalensis. Ethanolic extract (Hn.Cr) was prepared by maceration and was chemically characterized by HPLC methods. Antioxidant and antimicrobial properties were assessed in three in vitro models. Toxicity profile of Hn.Cr was evaluated in acute toxicological studies. Alloxan-induced diabetes model was used to access the antidiabetic attributes of Hn.Cr. Excision wound healing model was used to access the wound healing potential of Hn.Cr in alloxan-induced diabetic rats. HPLC analysis of Hn.Cr revealed the presence of phenolic and flavonoids compounds. Data of in vitro antioxidant assays showed that Hn.Cr has moderate radical scavenging potential. In vitro antimicrobial testing results revealed that Hn.Cr was active against bacterial strains (Gram +ve and Gram -ve) while no activity was observed against fungal strains used in the current study. Acute toxicity study results showed that extract was safe up to the dose of 5000 mg/kg. In vivo antidiabetic study revealed that Hn.Cr significantly (p

With the advancement of technology, the maximum data hiding capacity and security of cover objects have become a very challenging task for researchers, particularly in text carrier. Text carrier depicts low hiding capacity but more secure for the detection of confidential information. It demands novelty in data hiding algorithms. In this regard, a novel algorithm is proposed by using steganography and cryptography together for the enhancement of capacity and security of confidential data. The recommended algorithm uses a linguistic steganography method to conceal data into the Arabic text carrier. In the described algorithm, the identification of secret information from text files is hard due to less redundant bits in the text as compared to the image, audio, and video steganographic mediums. The current solution uses Unicode characters such as Zero-Width-Character (ZWC) and Zero-Width-Joiner (ZWJ) to hide the secret information. Before hiding confidential information, secret data is encrypted by using bit inversion due to which algorithm achieved high security. It is observed from the simulation results that the proposed algorithm successfully achieved high cover medium capacity, security, and robustness.

Mycotoxins are known as natural food toxins produced by certain fungi grown on various crops during pre-harvest and post-harvest conditions. During analysis, sample selection and extraction followed by clean-up is an essential process for accurate detection. These steps ensured the accuracy, precision as well as the reliability, and reproducibility of results. There are various techniques available for the detection of mycotoxins in food and food products. However, Liquid chromatography with tandem mass spectrometry (LC–MS/MS) is the most widely used technique. It can be used effectively to detect multiple mycotoxins as well as masked or modified mycotoxins with acceptable accuracy and precision. Therefore, the review has focused on discussing the co-occurrence, masked mycotoxins, sampling, the extraction of mycotoxins, and LC–MS/MS as an analytical tool for the accurate and precise detection mycotoxins.

S-adenosylmethionine decarboxylase (SAMDC) mediates the biosynthesis of polyamines (PAs) and plays a positive role in plants’ response to adversity stress tolerance. In this study, we isolated a SAMDC gene from white clover, which is located in mitochondria. It was strongly induced when white clover exposed to drought (15% PEG6000), salinity (200 mM NaCl), 20 μM spermidine, 100 μM abscisic acid, and 10 mM H2O2, especially in leaves. The INVSc1 yeast introduced with TrSAMDC1 had tolerance to drought, salt, and oxidative stress. Overexpression of TrSAMDC1 in Arabidopsis showed higher fresh weight and dry weight under drought and salt treatment and without growth inhibition under normal conditions. Leaf senescence induced by drought and saline was further delayed in transgenic plants, regardless of cultivation in 1/2 MS medium and soil. During drought and salt stress, transgenic plants exhibited a significant increase in relative water content, maximum photosynthesis efficiency (Fv/Fm), performance index on the absorption basis (PIABS), activities of antioxidant protective enzymes such as SOD, POD, CAT, and APX, and a significant decrease in accumulation of MDA and H2O2 as compared to the WT. The concentrations of total PAs, putrescine, spermidine, and spermidine in transgenic lines were higher in transgenic plants than in WT under normal and drought conditions. These results suggested that TrSAMDC1 could effectively mitigate abiotic stresses without the expense of production and be a potential candidate gene for improving the drought and salt resistance of crops.

Single-atom catalysts show a promising future in many reactions even though great challenges still remain such as facile synthesis and long stability. In this work, a single-atom Pd catalyst attached to a designed N8 Lewis base species (Pd1-N8/CNT) is synthesized with cyclic voltammetry (CV) method. The catalyst demonstrates long stability and enhanced C2H4 selectivity in selective hydrogenation of acetylene at 40 °C. CV is carried out in a three-electrode setup with PdO/CNT as the working electrode in NaN3 solution. HAADF-STEM confirms single-atom Pd sites are successfully isolated. XPS measurements and Bader charge calculations indicate N8 is effectively synthesized on CNT substrate after CV treatment while single-atom Pd is stabilized by attaching to the end N of N8. Acetylene-temperature programed desorption (C2H2-TPD) and density functional theory (DFT) calculations suggest C2H2 favors the π bonding on single Pd atom, while H2 dissociates on the N atom (next to Pd) instead of conventionally on Pd. The synergistic effect favors C2H4 formation but prevents full hydrogenation of acetylene to C2H6. This work opens up a new perspective to design and synthesize more selective catalysts with isolated single-atom sites.

This study deals with the optimization of best working conditions in molten melt for the production of hydrogen (H2) gas. Limited research has been carried out on how electrochemical process occurs through steam splitting via molten hydroxide. 54 combinations of cathode, anode, temperature and voltage have been investigated for the optimization of best working conditions with molten hydroxide for hydrogen gas production. All these electrochemical investigations were carried out at 225 to 300°C temperature and 1.5 to 2.5 V applied voltage values. The current efficiency of 90.5, 80.0 and 68.6% has been achieved using stainless steel anodic cell with nickel, stainless steel and platinum working cathode respectively. For nickel cathode, an increase in the current directly affected the hydrogen gas flow rate at cathode. It can be hypothesized from the noted results that increase in current is directly proportional to operating temperature and applied voltage. Higher values were noted when the applied voltages increased from 1.5 to 2.5 V at 300°C, the flow rate of hydrogen gas increased from 1.5 to 11.3 cm3 min−1, 1.0 to 13 cm3 min−1 in case of electrolysis @ stainless steel and @ graphite anode respectively. It is observed that the current efficiency of stainless steel anodic cell was higher than the graphite anodic cell. Therefore, steam splitting with the help of molten salts has shown an encouraging alternate to current methodology for H2 fuel production.

New avibactam derivatives in which amide moiety is replaced by substituted amidine groupings were obtained in several steps, the key step having involved the conversion of 2-positioned cyano group of the 1,6-diazabicyclo[3.2.1]-octane framework into the amidine one. Synergistic antibacterial activity of the new compounds in combination with meropenem infers the agonistic effect of these derivatives against β-lactamases.

© 2020 Hydrogen Energy Publications LLC There are still gaps in the field of reference electrode that is needed to assist electrolysis in high temperature electrolytes (e.g. molten hydroxides) for H2 gas production. This research aims to fill the gaps by preparing Ni/Ni(OH)2 reference electrode and more importantly testing its effectiveness against important performance factors including; ion conducting membrane (e.g. mullite tubes), internal electrolyte composition, working temperature and electrochemical control (e.g. potential scan rate). Then, this reference electrode was used to study the electrocatalytic activity various cheaper working electrode materials including; stainless steel (St.st), Ni, Mo and Ag in comparison with Pt by the means of chronoamperometry and voltammetry. The effect of introducing steam into electrolyte (eutectic mixture of NaOH and KOH) on the electrocatalytic activity of these working electrodes was also studied. It was observed that the potential of hydrogen evolution with different working electrodes followed an order as; Pt > Ni > St. st > Ag > Mo (positive to negative). The performance of each working electrode was confirmed through chronoamperometry for hydrogen evolution at a constant potential of −0.7 V. It was also found in cyclic voltammetry and confirmed by chronoamperometry that the introduction of steam was apparent as increasing the current density at cathodic limit for hydrogen evolution. This study could help to develop non-precious metal electrodes for the production of hydrogen fuel. In future, there will be a potential in the threshold concentration of steam for H2 gas production.

Point cloud processing has gained consideration for 3D object recognition and classification tasks. In this context, an important task is to detect the distinct and repeatable 3D keypoints. Many 3D keypoint detectors with low repeatability and distinctiveness have been proposed. The detection of highly repeatable and distinct keypoints is still an open problem. To address this issue, we propose a fuzzy logic and Histogram of Normal Orientation (HoNO)-based 3D keypoint detection scheme for Point Cloud (PC) data. To measure saliency, we exploit the structure of the PC and compute the eigenvalues of the covariance matrix and the HoNO to measure saliency. The histogram (HoNO) salient value is computed by the kurtosis values, which estimate the spread of the histogram. From the kurtosis and smallest eigenvalues, we compute the difference of the kurtosis values and the difference of the smallest eigenvalues of the query point against all the neighbouring points. The difference of kurtosis values and difference of smallest eigenvalues are applied to a fuzzy rule-based scheme for the keypoints detection. We compare the proposed algorithm with the state-of-the-art 3D keypoint detectors on five benchmark datasets. Experimental results demonstrate the superior performance of the proposed detector on most of the benchmark datasets both in terms of absolute and relative repeatability.