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Abstract  

An understanding of the mechanisms by which water molecules are held within a substance or at its surface, either by physical or chemical processes, is of importance in the formulation, preparation and storage of a wide variety of substances. The traditional experimental techniques which have been used to make measurements on samples exposed to specific levels of relative humidity, (e.g. using desiccators containing saturated salt solutions), are slow, laborious, inaccurate, and provide a limited amount of data. This paper describes the conception, operation, and facilities of a new system which by employing recently developed electronic components and transducers, significantly advances the performance capability for moisture sorption analysis.

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Abstract

The glass transition temperature (Tg) regions of polymers and composites were studied using static force thermomechanometry and modulated temperature thermomechanometry (mT-TM). Modulated temperature allowed measurement of linear thermal expansion coefficient and glass transition as reversing phenomena, independent of any residual cure and relaxations that are non-reversing in nature. The reversing dimension change curves were well defined with continuous expansion that increased after Tg, though sensitivity decreased with crosslinking and fibre content. The non-reversing dimension change curves showed the maximum variation and revealed complex changes, and the non-reversing characteristics were confirmed by repeated scans, both upon cooling or re-heating. Non-reversing curves showed contractions with increasing temperature. Lissajous figures demonstrated that temperature modulation deviated significantly from linear response in the temperature range below Tg, and during the Tg range, steady state was not maintained. Measurements made in mT-TM mode were compared with modulated force TM where Tg was revealed as a peak in loss modulus or tan(δ), whilst reversing events were consistent with changes in storage modulus.

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Abstract  

In this work, we describe and evaluate the use of the Fourier transform infra red (FTIR) spectroscopy in DRIFT mode (diffuse reflectance infra red Fourier transform) in an environmental device to follow the functional evolution of cellulose during thermal treatments. The potentialities (and difficulties) of the technic are given.

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Why aren't the social sciences Darwinian?

Introduction to a special issue of the Journal of Evolutionary Psychology

Journal of Evolutionary Psychology
Authors: Alex Mesoudi, Djuke Veldhuis, and Robert A. Foley

Abstract

At the inception of the social sciences in the late 19th century, early psychologists, anthropologists, archaeologists and sociologists frequently proposed evolutionary explanations for social phenomena. Yet by the mid-20th century Darwin's theory had virtually disappeared from the social sciences, and most social scientists continue to reject evolutionary approaches within their disciplines. This special issue of the Journal of Evolutionary Psychology contains six papers each of which addresses the question of why social scientists rejected evolution, and why they still do. Three broad reasons are identified by our contributors. First, many social scientists past and present hold distorted views of evolution leading to, in our view, an unfounded rejection of evolutionary theory. This distortion might be addressed by improved education and communication of evolutionary theory. Second, many past applications of evolutionary theory to social phenomena have been inadequate for explaining the kinds of phenomena that social scientists are most interested in, such as rapid cultural change and the emergence of large-scale cooperative institutions. This situation is changing as modern Darwinian approaches incorporate behavioural flexibility, group-level explanations and culture. Finally, certain strands of the social sciences have rejected the scientific method in general, instead adopting non-scientific perspectives such as social constructionism. While this is a broader epistemological issue, the application of evolutionary methods to social phenomena may provide the best and most direct support for the value of the scientific method.

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Scientometrics
Authors: Kathryn Riley, Robert Multhauf, and A. Donovan

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Abstract

Background and aims

The primary objective of the present research is to investigate the drivers of technological addiction in college students — heavy users of Information and Communication Technology (ICT). The study places cell phone and instant messaging addiction in the broader context of consumption pathologies, investigating the influence of materialism and impulsiveness on these two technologies. Clearly, cell phones serve more than just a utilitarian purpose. Cell phones are used in public and play a vital role in the lives of young adults. The accessibility of new technologies, like cell phones, which have the advantages of portability and an ever increasing array of functions, makes their over-use increasingly likely.

Methods

College undergraduates (N = 191) from two U.S. universities completed a paper and pencil survey instrument during class. The questionnaire took approximately 15–20 minutes to complete and contained scales that measured materialism, impulsiveness, and mobile phone and instant messaging addiction.

Results

Factor analysis supported the discriminant validity of Ehrenberg, Juckes, White and Walsh's (2008) Mobile Phone and Instant Messaging Addictive Tendencies Scale. The path model indicates that both materialism and impulsiveness impact the two addictive tendencies, and that materialism's direct impact on these addictions has a noticeably larger effect on cell phone use than instant messaging.

Conclusions

The present study finds that materialism and impulsiveness drive both a dependence on cell phones and instant messaging. As Griffiths (2012) rightly warns, however, researchers must be aware that one's addiction may not simply be to the cell phone, but to a particular activity or function of the cell phone. The emergence of multi-function smart phones requires that research must dig beneath the technology being used to the activities that draw the user to the particular technology.

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Abstract  

The part I of this work discusses the potentialities and limits of the in situ spectroscopic analysis of cellulose by Diffuse Reflectance Infrared Fourier Transform in an environment device. In this paper, we describe: the in situ evolutions of cellulose from 25 to 270C under N2 or air; the evolution of a partially thermolyzed cellulose residue during thermal treatment from 25 to 450C and finally the oxidation in air of a cellulose char at 300C. We observe a limited evolution of the cellulose below 270C. Only some carbonyle groups issued from rearrangement of cellulose chains are formed. The thermal treatment of the thermolyzed residue leads to a progressive aromatization of the solid between 270 and 450C. The oxidation in air induces the formation of oxygenated groups (carbonyles, carboxylic acids, lactones) and proceeds by reaction on both aliphatic and aromatic sites. Some dehydration of carboxylic groups to anhydrides are observed.

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Introduction

Once thought a rarely used drug, LSD use is steadily increasing among US adults. A greater understanding of social factors and psychological determinants leading to lifetime LSD use can assist health educators and professionals in treating this growing problem. This study analyzed psychosocial factors related to LSD use among a national sample of adults.

Methods

A secondary data analysis of the 2017 National Survey on Drug Use and Health was performed.

Results

Results from the final multivariate logistic regression revealed that those who were male, African American or Hispanic, used alcohol, ecstasy, marijuana, inhalants, cocaine, and cigarettes before the age of 21 years, thought about suicide, got a kick out of doing things risky, and tested oneself to do risky things were more likely to use LSD.

Conclusions

This suggests that psychodynamic processes, for example, possible activation of emotional conflicts – can take place spontaneously – during ayahuasca intake in this particular setting. Some participants attributed symbolic meaning to the visionary content, which was more likely to take place in psychotherapeutically motivated clients. The specific setting influence as well as corresponding expectations of the participants in native wisdom could have considerable influence on experiences and interpretations, such as communication with entities as well as receiving personal teachings.

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Abstract  

Titanium nitride films /3.0 and 3.8 microns/ deposited by the magnetron sputtering technique on silicon substrates and the commercially procured compound sputter target material are characterized for their bulk compositions by non-destructive 14 MeV neutron activation analysis /NAA/. The practical sensitivity and precision obtained under the present experimental conditions are 0.7 mg and 5% in the case of titanium and 0.1 mg and 8% in the case of nitrogen, respectively. The bulk composition of the films seems to conform to stoichiometric nitride, TiN, while the presence of oxygen could not be precluded in the compound target material.

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Central European Geology
Authors: Olle Selinus, Robert B. Finkelman, Jose A. Centeno, and Mark Cave
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