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Abstract  

A simple method for the electrodeposition of elemental arsenic (As) on a metal backing from aqueous solutions has been developed. The method was successfully applied to stable As (75As). Thin (2.5 mg cm−2) coherent, smooth layers of the metalloid on Ti foils (2.5 μm thickness) were obtained. Electrodeposits served as targets for 75As(n,γ) 76As neutron capture experiments at Los Alamos Neutron Science Center (LANSCE). Respective 73As(n,γ) 74As experiments are planned for the near future, and 73As targets will be prepared in a similar fashion utilizing the new electrodeposition method. The preparation of an 73As (half-life 80.3 days) plating bath solution from proton irradiated germanium has been demonstrated. Germanium target irradiation was performed at the Los Alamos Isotope Production Facility (IPF).

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Chañar (Geoffroea decorticans- Fabaceae) is a tree from South America that is normally infected with galls originated by insects. One of its parasites is Allodiplosis crassa (Cecidomyiidae, Diptera) which produces globular galls with sticky prolongations. Since this plant has medicinal uses in Argentina, its infestation could alter the quality of the plant drug. The surface of insect-induced galls usually contains defensive features such as trichomes, increased hardness and an increase in the content of polyphenolic compounds. The objective of this research is to assess the structural and histochemical features of the gall and to compare the content of polyphenolic metabolites in the gall, in the healthy leaf and in lignified stems of G. decorticans. The methanolic extract from the galls showed the highest amount of polyphenolic and proanthocyanidins and the lowest amount of hydroxycinnamic derivatives and flavonoids compared to the methanolic extract of the leaves. The photographs taken from the external surface of the gall showed that some prolongations have heads. The histochemical analysis showed that the prolongations have a high amount of proanthocyanidins and flavonoids; and that the heads are reactive to Sudan III. These phytochemical and histological characteristics may have a defensive role against harmful fungi and parasites that attack the larvae of the A. crassa. The results of this study show the presence of defensive features in an insect-induced gall of a medicinal plant with potential implications in the pharmacological activity of this species. This is the first report of a histochemical and phytochemical study in G. corticans galls.

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Journal of Behavioral Addictions
Authors: Bach Xuan Tran, Giang Hai Ha, Giang Thu Vu, Chi Linh Hoang, Son Hoang Nguyen, Cuong Tat Nguyen, Carl. A. Latkin, Wilson WS Tam, Cyrus S. H. Ho, and Roger C. M. Ho

Abstract

Background and aims

Excessive use of electronic devices has become a major global problem. However, little is known about the development and current landscape of research concerning this field. This study aimed at exploring the overall publication trend and topics of research on the overuse of electronic devices and the Internet from 1971 to 2017.

Methods

We systematically searched the Web of Science (WoS) and Scopus databases for published articles on the excessive use of electronic devices and the Internet. Data regarding the publication volume, international collaborations, and geographical locations were analyzed by bibliometrics analysis. Latent Dirichlet Allocation (LDA) was undertaken to categorize publications into different research topics.

Results

A total of 2,276 papers from the WOS and 600 papers from the Scopus were included. We found a dramatic increase in the number of scientific papers towards addiction to electronic devices and the Internet. The United State led in all publication parameters including the total number of papers and total citations. China, Korea and Taiwan were among the most prolific countries/regions. Smartphone addiction was the main concern, and the relationship between the overuse of electronic devices and the Internet and mental health issues have been highlighted. On the other hand, our study found a limited appearance of discussion on effective treatment and intervention.

Discussion and Conclusion

The findings of this study call for more national and international cooperation in evaluating and intervening addiction to electronic devices and the Internet to gather more knowledge about this phenomenon and evaluate the effectiveness of treatment.

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