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Summary

To control the quality of Euonymus fortunei (Turcz.) Hand.-Mazz., a simple and reliable method of high-performance liquid chromatography (HPLC) coupled with photodiode array detector (PAD) was developed for both fingerprint analysis and quantitative determination. Four representative flavonoids, namely, kaempferol-3-O-β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl-7-O-β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranoside (I), kaempferol-3,7-O-α-dirhamnopyranoside (II), apigenin-7-O-β-D-glucopyranoside (III), and kaempferol-3-(4″-O-acetyl)-O-α-L-rhamnopyranoside-7-O-α-L-r hamnopyranoside (IV) isolated from E. fortunei, were used as reference compounds and simultaneously determined by the validated HPLC method. The unique properties of the chromatographic fingerprint were validated by analyzing 11 batches of E. fortunei, E. japonicus, E. laxiflorus, E. myrianthus, and E. hamiltonianus samples. Our results revealed that the chromatographic fingerprint combined with similarity measurement could efficiently identify and distinguish E. fortunei from the other investigated Euonymus species.

Open access
Nanopages
Authors:
Robert Vajtai
,
Sujit K. Biswas
,
Binqing Wei
,
Gouwen Meng
,
Yung Joon Jung
, and
Pulickel M. Ajayan

Single and multiwalled carbon nanotubes have attracted significant interest due to their one-dimensional structure and unique electrical and mechanical properties. Among the wide variety of their potential applications most importantly they offer potential to serve as building blocks for future electronic device architectures [1, 2, 3, 4, 5, 6]. Carbon nanotubes may serve as active or passive electronic elements; and as passive elements they may serve as interconnects both on short and long ranges [7, 8]. The most essential prerequisite for realizing CNT architectures is to be able to grow nanotubes at controlled sites, in predetermined orientations and to form interconnections. Significant progresses in growing aligned carbon nanotube films have been made recently with a combined approach of the floating catalyst method using pre-patterned templates and chemical vapor deposition (CVD) [9, 10, 11, 12]. Recently we summarized our work on growing architectures of carbon nanotubes, which might be integrated into microelectronic circuits [13]. While the predefined growth of the above mentioned large nanotube structures is important and receives a lot of attention characterization of the product also deserves similarly high attention being a key for future applications and giving the real importance and purpose of the growth efforts. In this paper, we report some of our works, which are directed towards electrical tests on CNTs, namely high current carrying capacity; vertically organized multiwalled nanotubes showing the possible usage of highly ordered and well-shaped tubes; and characterization of singlewalled nanotube junctions.

Open access
Nanopages
Authors:
S. Talapatra
,
T. Kim
,
B. Q. Wei
,
S. Kar
,
R. Vajtai
,
G. V. S. Sastry
,
M. Shima
,
D. Srivastava
, and
P. M. Ajayan

We report on the room temperature ferromagnetism observed in heat treated nanocrystalline diamonds. By systematic annealing of nanocrystalline diamond, graphitic nanoclusters having finite magnetization with well-defined hysteresis and coercivity, and a Curie temperature (TC) well above 400 K (estimated TC ~ 590 K), were synthesized. Using detailed analysis of the structural modification at various annealing stages, with Raman Spectroscopy and High Resolution Transmission Electron Microscopy, we show that the carbon bonding configuration has important consequence to the observed magnetism in these samples. These findings could lead to controlled fabrication of metal free magnetic carbon system.

Open access

Patrinia scabra Bunge has long been used in clinic as a traditional Chinese medicine for treating leukemia and cancer and regulating host immune response. Despite their wide use in China, no report on system analysis on their chemical constituents is available so far. The current study was designed to profile the fingerprint of ethyl acetate extract of it, and in addition, to characterize the major fingerprint peaks and determine their quantity. Therefore, a detailed gradient high-performance liquid chromatography was described to separate more than 30 compounds with satisfactory resolution in P. scabra Bunge. Based on the chromatograms of 10 batches samples, a typical high-performance liquid chromatographic (HPLC) fingerprint was established with 23 chromatographic peaks being assigned as common fingerprint peaks. Furthermore, a quadrupole time of flight mass spectrometry (Q-TOF/MS) was coupled for the characterization of major compound. As (+)-nortrachelogenin was the most predominant compound in P. scabra Bunge, the quantification on it was also carried out with the method being validated. As a result, (+)-nortrachelogenin was found to be from 1.33 to 2.21 mg g−1 in this plant material. This rapid and effective analytical method could be employed for quality assessment of P. scabra Bunge, as well as pharmaceutical products containing this herbal material.

Open access
Journal of Behavioral Addictions
Authors:
John B. Saunders
,
Wei Hao
,
Jiang Long
,
Daniel L. King
,
Karl Mann
,
Mira Fauth-Bühler
,
Hans-Jürgen Rumpf
,
Henrietta Bowden-Jones
,
Afarin Rahimi-Movaghar
,
Thomas Chung
,
Elda Chan
,
Norharlina Bahar
,
Sophia Achab
,
Hae Kook Lee
,
Marc Potenza
,
Nancy Petry
,
Daniel Spritzer
,
Atul Ambekar
,
Jeffrey Derevensky
,
Mark D. Griffiths
,
Halley M. Pontes
,
Daria Kuss
,
Susumu Higuchi
,
Satoko Mihara
,
Sawitri Assangangkornchai
,
Manoj Sharma
,
Ahmad El Kashef
,
Patrick Ip
,
Michael Farrell
,
Emanuele Scafato
,
Natacha Carragher
, and
Vladimir Poznyak

Online gaming has greatly increased in popularity in recent years, and with this has come a multiplicity of problems due to excessive involvement in gaming. Gaming disorder, both online and offline, has been defined for the first time in the draft of 11th revision of the International Classification of Diseases (ICD-11). National surveys have shown prevalence rates of gaming disorder/addiction of 10%–15% among young people in several Asian countries and of 1%–10% in their counterparts in some Western countries. Several diseases related to excessive gaming are now recognized, and clinics are being established to respond to individual, family, and community concerns, but many cases remain hidden. Gaming disorder shares many features with addictions due to psychoactive substances and with gambling disorder, and functional neuroimaging shows that similar areas of the brain are activated. Governments and health agencies worldwide are seeking for the effects of online gaming to be addressed, and for preventive approaches to be developed. Central to this effort is a need to delineate the nature of the problem, which is the purpose of the definitions in the draft of ICD-11.

Open access

Including gaming disorder in the ICD-11: The need to do so from a clinical and public health perspective

Commentary on: A weak scientific basis for gaming disorder: Let us err on the side of caution (van Rooij et al., 2018)

Journal of Behavioral Addictions
Authors:
Hans-Jürgen Rumpf
,
Sophia Achab
,
Joël Billieux
,
Henrietta Bowden-Jones
,
Natacha Carragher
,
Zsolt Demetrovics
,
Susumu Higuchi
,
Daniel L. King
,
Karl Mann
,
Marc Potenza
,
John B. Saunders
,
Max Abbott
,
Atul Ambekar
,
Osman Tolga Aricak
,
Sawitri Assanangkornchai
,
Norharlina Bahar
,
Guilherme Borges
,
Matthias Brand
,
Elda Mei-Lo Chan
,
Thomas Chung
,
Jeff Derevensky
,
Ahmad El Kashef
,
Michael Farrell
,
Naomi A. Fineberg
,
Claudia Gandin
,
Douglas A. Gentile
,
Mark D. Griffiths
,
Anna E. Goudriaan
,
Marie Grall-Bronnec
,
Wei Hao
,
David C. Hodgins
,
Patrick Ip
,
Orsolya Király
,
Hae Kook Lee
,
Daria Kuss
,
Jeroen S. Lemmens
,
Jiang Long
,
Olatz Lopez-Fernandez
,
Satoko Mihara
,
Nancy M. Petry
,
Halley M. Pontes
,
Afarin Rahimi-Movaghar
,
Florian Rehbein
,
Jürgen Rehm
,
Emanuele Scafato
,
Manoi Sharma
,
Daniel Spritzer
,
Dan J. Stein
,
Philip Tam
,
Aviv Weinstein
,
Hans-Ulrich Wittchen
,
Klaus Wölfling
,
Daniele Zullino
, and
Vladimir Poznyak

The proposed introduction of gaming disorder (GD) in the 11th revision of the International Classification of Diseases (ICD-11) developed by the World Health Organization (WHO) has led to a lively debate over the past year. Besides the broad support for the decision in the academic press, a recent publication by van Rooij et al. (2018) repeated the criticism raised against the inclusion of GD in ICD-11 by Aarseth et al. (2017). We argue that this group of researchers fails to recognize the clinical and public health considerations, which support the WHO perspective. It is important to recognize a range of biases that may influence this debate; in particular, the gaming industry may wish to diminish its responsibility by claiming that GD is not a public health problem, a position which maybe supported by arguments from scholars based in media psychology, computer games research, communication science, and related disciplines. However, just as with any other disease or disorder in the ICD-11, the decision whether or not to include GD is based on clinical evidence and public health needs. Therefore, we reiterate our conclusion that including GD reflects the essence of the ICD and will facilitate treatment and prevention for those who need it.

Open access