scholarly journals Metabolomics-based analysis of miniature flask contents identifies tobacco mixture use among the ancient Maya

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mario Zimmermann ◽  
Korey J. Brownstein ◽  
Luis Pantoja Díaz ◽  
Iliana Ancona Aragón ◽  
Scott Hutson ◽  
...  
Keyword(s):  
Analytical Techniques ◽  
Chemical Compounds ◽  
Ancient Maya ◽  
Organic Residues ◽  
Ceramic Vessel ◽  
Museum Exhibitions ◽  
Maya Area ◽  
Formed Part ◽  
First Time ◽  
Archaeological Excavations

AbstractA particular type of miniature ceramic vessel locally known as “veneneras” is occasionally found during archaeological excavations in the Maya Area. To date, only one study of a collection of such containers successfully identified organic residues through coupled chromatography–mass spectrometry methods. That study identified traces of nicotine likely associated with tobacco. Here we present a more complete picture by analyzing a suite of possible complementary ingredients in tobacco mixtures across a collection of 14 miniature vessels. The collection includes four different vessel forms and allows for the comparison of specimens which had previously formed part of museum exhibitions with recently excavated, untreated containers. Archaeological samples were compared with fresh as well as cured reference materials from two different species of tobacco (Nicotiana tabacum and N. rustica). In addition, we sampled six more plants which are linked to mind-altering practices through Mesoamerican ethnohistoric or ethnographic records. Analyses were conducted using UPLC-MS metabolomics-based analytical techniques, which significantly expand the possible detection of chemical compounds compared to previous biomarker-focused studies. Results include the detection of more than 9000 residual chemical features. We trace, for the first time, the presence of Mexican marigold (Tagetes lucida) in presumptive polydrug mixtures.

Amphilochius of Iconium and Lycaonian Asceticism

2011 ◽  
Vol 101 ◽  
pp. 185-205
Author(s):  
Peter Thonemann
Keyword(s):  
Late Antiquity ◽  
Fourth Century ◽  
Orthodox Christian ◽  
Ascetic Communities ◽  
Formed Part ◽  
First Time

AbstractNon-orthodox Christian asceticism in Late Antiquity is known to us largely through the distorting lens of orthodox heresiology. This paper aims to reassess the character of the ascetic communities of rural Lycaonia in the fourth century a.d. in the light of the surviving funerary and ecclesiastical epigraphy, including three inscriptions published here for the first time. We are fortunate to be able to read these texts in the light of a neglected work of orthodox polemic, Amphilochius’ Against False Asceticism, the work of an embattled orthodox bishop at Iconium in the late 370s a.d. This treatise formed part of a successful campaign to stigmatize the Lycaonian ascetics as heretics, a position which was enshrined in Theodosius’ anti-heretical legislation of a.d. 381–3.

Sphere-like CoS with nanostructures as peroxidase mimics for colorimetric determination of H2O2 and mercury ions

RSC Advances ◽  
2016 ◽  
Vol 6 (71) ◽  
pp. 66963-66970 ◽  
Author(s):  
Haiguan Yang ◽  
Junqi Zha ◽  
Peng Zhang ◽  
Yuhao Xiong ◽  
Linjing Su ◽  
...  
Keyword(s):  
Solvothermal Method ◽  
Analytical Techniques ◽  
Colorimetric Determination ◽  
Mercury Ions ◽  
Peroxidase Mimics ◽  
First Time ◽  
Facile Solvothermal Method

CoS, which was prepared using a facile solvothermal method, and characterized using various analytical techniques, was demonstrated for the first time to exhibit intrinsic peroxidase-like activity.

scholarly journals A visual method based on Lewis dot electron structures (VISLEDS) for teaching inorganic formulation

2020 ◽  
Author(s):  
Abigail Jimenez
Keyword(s):  
Secondary School ◽  
Cognitive Load ◽  
Secondary School Students ◽  
Chemical Compounds ◽  
School Students ◽  
Visual Method ◽  
Set Up ◽  
Visual Description ◽  
First Time ◽  
Theory Framework

Chemistry is usually seen as a difficult subject for secondary school students. One topic they struggle is when they face chemistry formulation for the first time. The concept of oxidation number is difficult for them. The level of abstraction required is still developing in their minds. We must help them visualise it, to understand bonding and, finally, the symbolic representation of chemical compounds.We find in chemistry a visual description for bond formation: Lewis diagrams. They explicitly show molecular bonds as paired electrons. By using this simple idea, we can introduce formulation to secondary school students. Starting with binary chemical compounds, included in 3rd year of secondary schools in Spain, we can set up the foundations for their future chemistry studies. Of course, the difficulty must be progressively introduced.In this work, we show how a visual method based on Lewis diagrams improves the performance of students when writing formulae of binary chemical compounds. One important difference with current literature on how Lewis dot structures are used in education, is that, while they are usually presented as a learning goal, here we use them as a means to an end.Our results suggest that the improvement is higher for students with previous lower academic performance, low scores in linguistic competencies, and high scores in visual and artistic competencies. Most importantly, it does not worsen performance for students with high scores in linguistic competencies and low scores in visual and artistic competencies. Mathematical competencies do not seem to be so good predictors for students’ performance.Finally, within the Cognitive Load Theory framework, we show how cognitive working load, as well as an approximation of extraneous cognitive load, can be estimated by using information theory measures involving the mistakes students make.

SECOND MILLENNIUM B.C. CHRONOLOGY AND THE ‘GREAT SETTLEMENT SHANG’ (14TH–11TH CENTURIES B.C.): INTRODUCTION

2020 ◽  
pp. 86-95
Author(s):  
Marina Е. Kuznetsova-Fetisova ◽  
Keyword(s):  
East Asia ◽  
19Th Century ◽  
Historical Data ◽  
Political History ◽  
Henan Province ◽  
Writing System ◽  
Place Of Origin ◽  
First Time ◽  
Political Figure ◽  
Archaeological Excavations

Second half of the II millennium B.C. can be considered as the time when the first writing system appeared in East Asia in the form of oracle bone inscriptions jiagu wen (甲骨文). For the first time those inscriptions sparked academic interest and received recognition at the end of 19th century, though their place of origin remained a mystery for some time. At the end of the 1920s Archaeological department of Institute of History and Philology Academia Sinica initiated archaeological excavations near modern city of Anyang, Henan province, PRC, because it was implied that the oracle bones with inscriptions had originated there. Archaeological excavations reveled a great ancient center in Anyang, including a cult center, workshops, and cemeteries including royal necropolis. Due to the fact that names of rulers, known from the transmitted texts, were often mentioned in those inscriptions, it was possible to identify the site as the last capital of Shang-Yin dynasty, so-called ‘Great Settlement Shang’ (14th–11th centuries B.C.). All these make the complex rather unique for its time, as it gives us a chance to connect pre-historical and historical data. Researchers managed to determine two relative chronologies (based on archaeological and epigraphic sources) and later to interconnect them and relate to the events mentioned in transmitted texts on early political history. Still, there is a number of problems in correlating those relative chronologies with absolute dates. Up to now the greatest project to coordinate chronology of the II millennium B.C. has been the project “Chronology of the Three Dynasties: Xia–Shang–Zhou” in 1996–2000, initiated by the Chinese political figure Song Jiang. Regardless of some international criticism of the projects’ results, a great number of scholars make use of them in their studies.

3. The divine king

2020 ◽  
pp. 23-42
Author(s):  
Matthew Restall ◽  
Amara Solari
Keyword(s):  
Classic Period ◽  
Ancient Maya ◽  
Regional Variations ◽  
Short Biography ◽  
Maya Area

“The divine king” begins with a short biography of the Maya k’uhul ajaw (supreme lord or king) known as 18-Rabbit. During the Classic period, rulers were viewed as divine kings or queens, like 18-Rabbit and Lady K’abel (“Waterlily-Hand”). The ancient Maya used a combination of a cyclical calendar and a linear calendar called the “Long Count.” The Maya area experienced regular intrusions from imperial Teotihuacan, often leading to economic and diplomatic partnerships. Most Mayas experienced war in their lifetimes. The “Collapse” at the end of the Classic period could more accurately be called a transition, with major regional variations. Some well-known Maya sites flourished after the Collapse.

scholarly journals Non-Isothermal Sublimation Kinetics of 2,4,6-Trinitrotoluene (TNT) Nanofilms

Molecules ◽  
2019 ◽  
Vol 24 (6) ◽  
pp. 1163 ◽  
Author(s):  
Walid Hikal ◽  
Brandon Weeks
Keyword(s):  
Activation Energy ◽  
Analytical Techniques ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
Absorbance Spectroscopy ◽  
Calculated Activation Energy ◽  
Sublimation Kinetics ◽  
Sublimation Rates ◽  
First Time ◽  
Kinetics Of

Non-isothermal sublimation kinetics of low-volatile materials is more favorable over isothermal data when time is a crucial factor to be considered, especially in the subject of detecting explosives. In this article, we report on the in-situ measurements of the sublimation activation energy for 2,4,6-trinitrotoluene (TNT) continuous nanofilms in air using rising-temperature UV-Vis absorbance spectroscopy at different heating rates. The TNT films were prepared by the spin coating deposition technique. For the first time, the most widely used procedure to determine sublimation rates using thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC) was followed in this work using UV-Vis absorbance spectroscopy. The sublimation kinetics were analyzed using three well-established calculating techniques. The non-isothermal based activation energy values using the Ozawa, Flynn–Wall, and Kissinger models were 105.9 ± 1.4 kJ mol−1, 102.1 ± 2.7 kJ mol−1, and 105.8 ± 1.6 kJ mol−1, respectively. The calculated activation energy agreed well with our previously reported isothermally-measured value for TNT nanofilms using UV-Vis absorbance spectroscopy. The results show that the well-established non-isothermal analytical techniques can be successfully applied at a nanoscale to determine sublimation kinetics using absorbance spectroscopy.

scholarly journals Genotoxic and Carcinogenic Potential of Compounds Associated with Electronic Cigarettes: A Systematic Review

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Isaac Armendáriz-Castillo ◽  
Santiago Guerrero ◽  
Antonella Vera-Guapi ◽  
Tiffany Cevallos-Vilatuña ◽  
Jennyfer M. García-Cárdenas ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Human Health ◽  
Conflicts Of Interest ◽  
Electronic Cigarettes ◽  
Chemical Compounds ◽  
Electronic Cigarette ◽  
Eligibility Criteria ◽  
Carcinogenic Potential ◽  
Chemical Abstracts Service ◽  
First Time

Background. Many studies, comparing the health associated risks of electronic cigarettes with conventional cigarettes focus mainly on the common chemical compounds found between them. Aim. Review chemical compounds found exclusively in electronic cigarettes and describe their toxic effects, focusing on electronic-cigarette-only and dual electronic-cigarette and conventional cigarette users. Data Sources. Literature search was carried out using PubMed. Study Eligibility Criteria. Articles related exclusively to conventional and electronic cigarettes’ chemical composition. Articles which reported to be financed from tobacco or electronic cigarettes industries, not reporting source of funding, not related to the chemical composition of electronic and conventional cigarettes and not relevant to tobacco research were excluded. Methods and Results. Chemical compounds reported in the selected studies were tabulated using the Chemical Abstracts Service registry number for chemical substances information. A total of 50 chemical compounds were exclusively reported to be present in electronic cigarettes. Crucial health risks identified were: eye, skin, and respiratory tract irritation, with almost 50% of incidence, an increment of 10% in cytotoxic effects, when compared to compounds in common with conventional cigarettes and around 11% of compounds with unknown effects to human health. Limitations. Articles reporting conflicts of interest. Conclusions and Implications of Key Findings. Despite being considered as less harmful for human health, compounds found in electronic cigarettes are still a matter of research and their effects on health are yet unknown. The use of these devices is not recommended for first time users and it is considered hazardous for dual users.

scholarly journals GC-MS Chemical Characterization of Main Components of Smilax Domingensis Wild. in Cuba

2018 ◽  
Vol 5 (4) ◽  
pp. 79 ◽  
Author(s):  
Pilar A. Soledispa ◽  
José González ◽  
Armando Cuéllar ◽  
Julio Pérez ◽  
Max Monan
Keyword(s):  
Mass Spectra ◽  
Chemical Constituents ◽  
Chemical Characterization ◽  
Ethanolic Extract ◽  
Chemical Compounds ◽  
Chemical Components ◽  
Analytical Technique ◽  
Main Components ◽  
First Time

A preliminary chemical characterization of main components of ethanolic extract with dried rhizomes of Smilax domingensis Wid. that grow in Cuba was done using a GCMS-QP2010 Ultra Shimadzu and the mass spectra of the compounds found in the extract was matched with the National Institute of Standards and Technology (NIST) library. After sample derivatization 125 chemical compounds were registered by the equipment and from them, 35 different chemical components were characterized and reported for the first time from this part of the plant in our country. The results demonstrate the developed method could be employed as a rapid and versatile analytical technique for identification of chemical constituents and quality control of Smilax domingensis.

scholarly journals Synthesis, Characterization and Mechanical Properties of Nanocomposites Based on Novel Carbon Nanowires and Polystyrene

2020 ◽  
Vol 10 (17) ◽  
pp. 5737
Author(s):  
Vasilis Kostas ◽  
Maria Baikousi ◽  
Nektaria-Marianthi Barkoula ◽  
Aris Giannakas ◽  
Antonios Kouloumpis ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Analytical Techniques ◽  
Polymer Nanocomposite ◽  
Precipitation Method ◽  
Templating Method ◽  
Polymer Properties ◽  
Wide Range ◽  
First Time ◽  
Range Of Values ◽  
Carbon Nanowires

Carbon into polymer nanocomposite is so far a common additive for the enhancement of the polymer properties. The properties of the polymer, such as thermal, and especially its mechanical properties, are improved by the homogeneously dispersed carbon nanoparticles on the polymer matrix. In this study, carbon wires in nano dimensions are, for the very first time, synthesized via the hard templating method from the silicate matrix MCM-41, and used as nano additives of polystyrene. The carbon nanowires were chemically oxidized, and further modified by attaching octadecylamine molecules, for the development of organic functionalities onto carbon nanowires surface. The nanocomposite materials of polystyrene with the modified carbon nanowires were prepared by a solution-precipitation method at three nano additive to polymer loadings (1, 3 and 5 wt%). The as-derived nanocomposites were studied with a combination of characterization and analytical techniques. The results showed that the thermal and mechanical properties of the polystyrene nanocomposites gradually improved while increasing nano-additive loading until 3 wt%. More specifically, the 3 wt% loading sample showed the best mechanical properties, while the 5 wt% sample was difficult to achieve satisfactory dispersion of carbon nanowires and consequently has a wide range of values.

Facebook and your corporate reputation

2016 ◽  
Vol 32 (11) ◽  
pp. 1-3
Keyword(s):  
Case Studies ◽  
Corporate Reputation ◽  
Design Methodology ◽  
Reading Time ◽  
Content Type ◽  
Pertinent Information ◽  
The Rich ◽  
Formed Part ◽  
First Time ◽  
Practical Implications

Purpose This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies. Design/methodology/approach This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context. Findings The year 2016 will in part be remembered, like all years divisible by four since 1896, by the Olympic spectacle that emanated for the first time from Brazil’s most famous city, Rio de Janeiro. But will it be the success, or the scandal that lingers longest in the memory? As with all modern Olympics, it was a blend of astonishing achievements, colorful celebration and sudden scandals – banned athletes, drug cheats, badly behaved swimmers and dodgy decisions all formed part of the rich canvas that enthralls millions each time it is held. Practical implications The paper provides strategic insights and practical thinking that have influenced some of the world’s leading organizations. Originality/value The briefing saves busy executives and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy-to-digest format.

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