scholarly journals Vibrational spectroscopic study of three Mg–Ni mineral series in white and greenish clay infillings of the New Caledonian Ni-silicate ores

2021 ◽  
Vol 33 (6) ◽  
pp. 743-763
Author(s):  
Emmanuel Fritsch ◽  
Etienne Balan ◽  
Sabine Petit ◽  
Farid Juillot
Keyword(s):  
Near Infrared ◽  
Bound Water ◽  
Oscillatory Zoning ◽  
Weakly Bound ◽  
Layer Silicates ◽  
Naturally Occurring ◽  
Mineral Phases ◽  
Vibrational Bands ◽  
The Individual ◽  
Individual Particles

Abstract. This study presents and discusses infrared spectroscopic data of well characterised, naturally occurring trioctahedral layer silicates of the serpentine (Srp), talc (Tlc), and sepiolite (Sep) mineral groups, which are found in reactivated faults and sequences of white and green clay veins (deweylite and garnierite) of the New Caledonian Ni-silicate ores. Bands assigned to the OH stretching vibrations of these 1:1 and 2:1 layer silicates in both the fundamental and first overtone regions of mid- and near-infrared (MIR and NIR) spectra, respectively, are compared to those reported in the literature for synthetic Mg–Ni series of the Srp and Tlc mineral groups. They are also presented according to the sequences of infillings recognised in the white and green veins of the Ni-silicate ores. The study reveals that serpentine-like (SL) minerals of the first sequences of clay infillings are residues of larger crystals of serpentines (lizardite, chrysotile, and antigorite) and that the newly formed talc-like (TL) minerals and Sep are the main Ni-bearing carriers of the Ni-silicate ores. Decreasing crystal size and order in serpentine species have major effects on vibrational bands. They favour the broadening of the OH stretching bands, the degradation of the signals assigned to the interlayer OH, and the enhancement of the signal related to weakly bound water molecules. The replacement of Mg by Ni in octahedral sites of the 2:1 layer silicates (TL, Sep) of the greenish clay infillings can be traced by specific OH stretching bands related to the Mg3OH, Mg2NiOH, MgNi2OH, and Ni3OH configurations in the fundamental (MIR) and first overtone (NIR) regions of the spectra. The dominance of the Mg3OH and Ni3OH configurations with respect to mixed configurations in the Mg–Ni mineral series of the clay infillings (mostly in the dominant TL minerals) suggests that Mg and Ni segregation is related to separate Mg-rich and Ni-rich mineral phases rather than to a cationic clustering within the individual particles. This segregation of Mg and Ni in discrete mineral phases is related to Mg–Ni oscillatory zoning patterns (banded patterns) and is reproduced at the scale of the Ni-silicate ores between the white (deweylite) and greenish (garnierite) veins of the reactivated faults.

scholarly journals A Synchrony-Based Classification Approach for Predicting Attitudes Using fNIRS

2020 ◽  
Author(s):  
Macrina C Dieffenbach ◽  
Grace S R Gillespie ◽  
Shannon M Burns ◽  
Ian A McCulloh ◽  
Daniel L Ames ◽  
...  
Keyword(s):  
Near Infrared ◽  
Neural Synchrony ◽  
Reference Groups ◽  
Functional Near Infrared Spectroscopy ◽  
Individual Level ◽  
Naturally Occurring ◽  
Neuroscience Research ◽  
Using Data ◽  
The Individual ◽  
Dispositional Differences

Abstract Social neuroscience research has demonstrated that those who are like-minded are also “like-brained.” Studies have shown that people who share similar viewpoints have greater neural synchrony with one another, and less synchrony with people who “see things differently.” Although these effects have been demonstrated at the group level, little work has been done to predict the viewpoints of specific individuals using neural synchrony measures. Furthermore, the studies that have made predictions using synchrony-based classification at the individual level used expensive and immobile neuroimaging equipment (e.g. fMRI) in highly controlled laboratory settings, which may not generalize to real-world contexts. Thus, this study uses a simple synchrony-based classification method, which we refer to as the neural reference groups approach, to predict individuals’ dispositional attitudes from data collected in a mobile “pop-up neuroscience” lab. Using functional near infrared spectroscopy (fNIRS) data, we predicted individuals’ partisan stances on a sociopolitical issue by comparing their neural timecourses to data from two partisan neural reference groups. We found that partisan stance could be identified at above-chance levels using data from dorsomedial prefrontal cortex (dmPFC). These results indicate that the neural reference groups approach can be used to investigate naturally-occurring, dispositional differences anywhere in the world.

scholarly journals Resolving Entangled JH-H-Coupling Patterns for Steroidal Structure Determinations by NMR Spectroscopy

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2643
Author(s):  
Danni Wu ◽  
Kathleen Joyce Carillo ◽  
Jiun-Jie Shie ◽  
Steve S.-F. Yu ◽  
Der-Lii M. Tzou
Keyword(s):  
Nmr Spectroscopy ◽  
1H Nmr Spectroscopy ◽  
Chemical Shifts ◽  
Atomic Level ◽  
Molecular Structures ◽  
Naturally Occurring ◽  
Structure Determinations ◽  
Ligand Interactions ◽  
Synthetic Steroids ◽  
The Individual

For decades, high-resolution 1H NMR spectroscopy has been routinely utilized to analyze both naturally occurring steroid hormones and synthetic steroids, which play important roles in regulating physiological functions in humans. Because the 1H signals are inevitably superimposed and entangled with various JH–H splitting patterns, such that the individual 1H chemical shift and associated JH–H coupling identities are hardly resolved. Given this, applications of thess information for elucidating steroidal molecular structures and steroid/ligand interactions at the atomic level were largely restricted. To overcome, we devoted to unraveling the entangled JH–H splitting patterns of two similar steroidal compounds having fully unsaturated protons, i.e., androstanolone and epiandrosterone (denoted as 1 and 2, respectively), in which only hydroxyl and ketone substituents attached to C3 and C17 were interchanged. Here we demonstrated that the JH–H values deduced from 1 and 2 are universal and applicable to other steroids, such as testosterone, 3β, 21-dihydroxygregna-5-en-20-one, prednisolone, and estradiol. On the other hand, the 1H chemical shifts may deviate substantially from sample to sample. In this communication, we propose a simple but novel scheme for resolving the complicate JH–H splitting patterns and 1H chemical shifts, aiming for steroidal structure determinations.

Misperceptions of Friendly Behavior as Sexual Interest: A Survey of Naturally Occurring Incidents

1987 ◽  
Vol 11 (2) ◽  
pp. 173-194 ◽  
Author(s):  
Antonia Abbey
Keyword(s):  
Gender Differences ◽  
Gender Difference ◽  
Sexual Activity ◽  
Sexual Interest ◽  
Large Percentage ◽  
Future Research ◽  
Naturally Occurring ◽  
Retrospective Reports ◽  
Sexual Intent ◽  
The Individual

The studies described in this article examine retrospective reports of naturally occurring misperceptions of friendliness as sexual interest. Previous research has demonstrated that men perceive other people and situations more sexually than women do. The purpose of this research was to examine how this gender difference in perceptions of sexuality is exhibited in actual interactions between women and men. Two surveys of undergraduates were conducted. The results indicated that a large percentage of both women and men had experienced such misperceptions, although more women had than men. Most of these incidents were quickly resolved without problems; however, others involved some degree of forced sexual activity and left the individual feeling angry, humiliated, and depressed. Gender differences in the characteristics of these incidents and reactions to them are described. The implications of these findings for future research on gender differences in perceptions of sexual intent are discussed.

scholarly journals Comparisons between SCIAMACHY and ground-based FTIR data for total columns of CO, CH<sub>4</sub>, CO<sub>2</sub> and N<sub>2</sub>O

2006 ◽  
Vol 6 (7) ◽  
pp. 1953-1976 ◽  
Author(s):  
B. Dils ◽  
M. De Mazière ◽  
J. F. Müller ◽  
T. Blumenstock ◽  
M. Buchwitz ◽  
...  
Keyword(s):  
Near Infrared ◽  
Polynomial Interpolation ◽  
Global Network ◽  
Target Species ◽  
Time Period ◽  
Order Polynomial ◽  
Temporal And Spatial ◽  
The Individual ◽  
Near Future ◽  
Total Column

Abstract. Total column amounts of CO, CH4, CO2 and N2O retrieved from SCIAMACHY nadir observations in its near-infrared channels have been compared to data from a ground-based quasi-global network of Fourier-transform infrared (FTIR) spectrometers. The SCIAMACHY data considered here have been produced by three different retrieval algorithms, WFM-DOAS (version 0.5 for CO and CH4 and version 0.4 for CO2 and N2O), IMAP-DOAS (version 1.1 and 0.9 (for CO)) and IMLM (version 6.3) and cover the January to December 2003 time period. Comparisons have been made for individual data, as well as for monthly averages. To maximize the number of reliable coincidences that satisfy the temporal and spatial collocation criteria, the SCIAMACHY data have been compared with a temporal 3rd order polynomial interpolation of the ground-based data. Particular attention has been given to the question whether SCIAMACHY observes correctly the seasonal and latitudinal variability of the target species. The present results indicate that the individual SCIAMACHY data obtained with the actual versions of the algorithms have been significantly improved, but that the quality requirements, for estimating emissions on regional scales, are not yet met. Nevertheless, possible directions for further algorithm upgrades have been identified which should result in more reliable data products in a near future.

scholarly journals An Experimental Observation Related To The Pore Space Between Particles Of Cement In Pastes At Early Ages

1988 ◽  
Vol 137 ◽  
Author(s):  
Hamlin M. Jennings
Keyword(s):  
Surface Charge ◽  
Experimental Observation ◽  
Cement Paste ◽  
Pore Space ◽  
The Individual ◽  
Individual Particles

Cement paste of water:cement ratios less than about 0.3 usually are not workable, but workability can be maintained at these lower water:cement ratios by using superplasticizers. A typical explanation [1] of the mechanism behind the effectiveness of superplasticizers is that they adsorb on the surface of cement particles and adjust the surface charge so that the particles become deflocculated. The individual particles flow more easily than larger flocs.

scholarly journals Statement of the Committee of Human Nutrition Science of the Polish Academy of Sciences on the use of dietary supplements containing vitamins and minerals by adults

2021 ◽  
Author(s):  
Agata Wawrzyniak ◽  
Katarzyna Przybyłowicz ◽  
Lidia Wądołowska ◽  
Jadwiga Charzewska ◽  
Danuta Górecka ◽  
...  
Keyword(s):  
Side Effects ◽  
General Population ◽  
Dietary Supplements ◽  
Dietary Supplementation ◽  
Dietary Recommendations ◽  
Nutrition Science ◽  
Naturally Occurring ◽  
The Individual ◽  
Academy Of Sciences ◽  
Usual Diet

The use of dietary supplements (supplementation) is the individual enrichment of the diet with ingredients naturally occurring in food. As a rule, dietary supplements should be used periodically. In nutritional practice, there are many indications for dietary supplementation, but the decision to take dietary supplements should be made by consumers wisely and only in justified situations, when there is a risk that the usual diet does not provide vitamins and minerals in an amount adequate to meet dietary recommendations. However, we should remember about the real dangers of taking too large doses of vitamins and minerals. Many people using dietary supplements, especially several types at the same time, may experience undesirable side effects and deterioration of health, and in addition, people taking medicines may seriously disrupt or weaken the effect of the drug, or even lack the therapeutic effect of the drug. The document presents 10 steps and rules for the use of dietary supplements available on the market, which are addressed to the general population.

scholarly journals Genetic variation in the oxytocin system and its link to social motivation in human infants

2021 ◽  
Author(s):  
Kathleen Marie Krol ◽  
Nauder Namaky ◽  
Mikhail Monakhov ◽  
Poh San Lai ◽  
Richard Ebstein ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Near Infrared ◽  
Social Motivation ◽  
Autism Spectrum ◽  
Brain Asymmetry ◽  
Functional Near Infrared Spectroscopy ◽  
Human Infants ◽  
Frontal Asymmetry ◽  
Frontal Brain ◽  
The Individual

Introduction. Variability in the motivation to approach or withdraw from others displayed in infancy is thought to have long-term effects on human social development. Frontal brain asymmetry has been linked to motivational processes in infants and adults, with greater left frontal asymmetry reflecting motivation to approach and greater right frontal asymmetry reflecting motivation to withdraw. We examined the hypothesis that variability in infants’ social motivation is linked to genetic variation in the endogenous oxytocin system. Specifically, we measured infants’ frontal brain asymmetry and later looking preferences to smiling and frowning individuals and assayed a single-nucleotide polymorphism in the CD38 gene (rs3796863) linked to autism spectrum disorder and reduced peripheral oxytocin levels. Methods. 77 11-month-old infants’ (36 female) brain responses were measured via functional near-infrared spectroscopy (fNIRS) while viewing four individuals display either smiles or frowns directed toward or away from them. This was followed by a person preference test using eyetracking. Results. Frontal brain asymmetry patterns evoked by direct-gaze faces significantly differed as a function of CD38 genotype. Specifically, while non-risk A-allele carriers displayed greater left lateralization to smiling faces (approach) and greater right lateralization to frowning faces (withdrawal), infants with the CC (ASD risk) genotype displayed withdrawal from smiling faces. During eyetracking, A-allele carriers showed a heightened preference for the individual who smiled, while CC infants preferred the individual who frowned.Conclusions. Our findings demonstrate that, from early in human ontogeny, genetic variation in the oxytocin system is linked to variability in brain and behavioral markers of social motivation.

Proof of the no-interaction theorem without hamiltonian and lagrangian formalism

1994 ◽  
Vol 445 (1923) ◽  
pp. 221-229 ◽  
Keyword(s):  
Angular Momentum ◽  
Conservation Laws ◽  
Lagrangian Formalism ◽  
The Individual ◽  
Individual Particles

The proofs of the no-interaction theorem have been given by many authors in the framework of hamiltonian and lagrangian formalism. They are based on the assumption that there is hamiltonian or lagrangian describing the interaction between particles. This paper presents the proof without such an assumption for one, two, three and four particles. We assume the conservation laws for the linear and angular momentum that are the sums of the respective quantities of individual particles. Then there is no interaction, i. e. the worldlines of the individual particles are straight.

scholarly journals The straggling of β-particles

1929 ◽  
Vol 125 (798) ◽  
pp. 420-445 ◽  
Keyword(s):  
Classical Theory ◽  
Experimental Investigations ◽  
Theoretical Treatment ◽  
A Value ◽  
Thin Foils ◽  
New Ideas ◽  
The Subject ◽  
The Individual ◽  
Individual Particles ◽  
Α Particles

When a beam of electric particles is passed through a sheet of matter the energy of the individual particles is reduced. The loss of energy is not the same for all the particles so that particles incident on the foil with the same energy emerge with different energies. This dispersion of the energy caused by the foil is known as the "straggling" of the particles. The straggling of α-particles has been the subject of several experimental investigations, and the theory in this case was adequately developed by Bohr in 1915. In the case of β-particles, however, the straggling was not experimentally investigated until quite recently and no theoretical treatment of the phenomenon has been given, the calculations of Bohr being, as he showed, applicable only to α-particles. The purpose of the work described in this paper is to develop a theory of the straggling of β-particles by thin foils and by means of it to interpret the results of experiment. The paper is arranged as follows. In 2 an account is given of the state of the experimental work on the subject, and in particular the effect of the complications introduced by "scattering" are considered. The formula derived by Bohr for the straggling of electric particles is given in 3 and its inapplicability to β-particles demonstrated. The present calculations of the straggling of β-particles are given in 4. The theory of the straggling of electric particles resolves itself into two parts. The first deals with the dynamics of collisions between electric particles and atoms, and is the same whether we are concerned with the straggling or some other phenomena such as ionisation of "stopping power." This may be called the fundamental theory and its requirements may be summarised in the function ϕ (Q) which express the frequency of collisions in which the electric particle loses energy of amount Q. The second part of the theory is the process of calculating the straggling by means of probability theory from the function ϕ . This may be regarded as the straggling theory proper and it is the main subject of 4. When the present calculations were started it was intended to calculate the straggling on the basis of classical theory only, the value of the function ϕ on this theory being definitely known. However, after some practice with the type of calculation involved it was decided to calculate the straggling for other forms of ϕ . From the results obtained it is possible to deduce the straggling corresponding to any form which ϕ may reasonably have, and if a new theory leads to a value of ϕ different from the classical value, the straggling on the new theory may readily be determined. Alternatively this fuller treatment may be used for the reverse process of calculating from the observed straggling the value of ϕ to which it corresponds. This is considered to be the most convenient procedure and in 5 the form of ϕ which explains the experimental results is deduced. this is compared in 6 with the value of ϕ on classical theory. A brief outline is given in 7 of certain new ideas concerning the nature of collisions of electric particles with electrons and atoms.

A Raman spectroscopic study of the natural carbonophosphates Na3MCO3PO4 (M = Mn, Fe, and Mg)

2021 ◽  
Author(s):  
Ekaterina Fomina ◽  
Evgeniy Kozlov ◽  
Mikhail Sidorov ◽  
Vladimir Bocharov
Keyword(s):  
Natural Increase ◽  
Mineral Species ◽  
Raman Shift ◽  
Russian Science ◽  
Epma Data ◽  
Raman Spectroscopic ◽  
Raman Spectroscopic Study ◽  
Mineral Phases ◽  
Vibrational Bands ◽  
Global Carbon

&lt;p&gt;Along with some other Na-minerals, carbonophosphates indicate a high initial Na activity in carbonatite and kimberlite melts, which is beneficial for petrological reconstructions. Because carbonophosphates are capable of incorporating large-ion lithophile and rare earth elements (REEs) in their structure, they can participate in the transport of these elements. Moreover, due to the presence of both [PO&lt;sub&gt;4&lt;/sub&gt;]&lt;sup&gt;3&amp;#8722;&lt;/sup&gt; and [CO&lt;sub&gt;3&lt;/sub&gt;]&lt;sup&gt;2&amp;#8722; &lt;/sup&gt;groups in carbonophosphates, these mineral phases play an important role in the Earth's global carbon and phosphate cycles. With all these properties, carbonophosphates have long attracted the attention of geologists. Raman spectroscopy appears to be one of the most suitable tools for their diagnosis, since they commonly present in rocks as small inclusions in other mineral grains. Despite this profit, only a few publications contain Raman characteristics of either natural or synthetic carbonophosphates.&lt;/p&gt;&lt;p&gt;We studied and compared Raman spectra of three natural carbonophosphate phases (sidorenkite, bonshtedtite, and bradleyite) with the general formula Na&lt;sub&gt;3&lt;/sub&gt;MCO&lt;sub&gt;3&lt;/sub&gt;PO&lt;sub&gt;4&lt;/sub&gt; (M = Mn, Fe, and Mg, correspondingly). These spectra showed from 21 to 24 vibrational bands, of which the two most intense (963&amp;#177;5 cm&lt;sup&gt;-1&lt;/sup&gt; &amp;#1080; 1074&amp;#177;3 cm&lt;sup&gt;-1&lt;/sup&gt;) correspond to the &amp;#957;1(P&amp;#8211;O) and &amp;#957;1(C&amp;#8211;O) modes. These two bands split due to the occurrence of isomorphic impurities. It was found that the crystallographic orientation of the sample influences the intensity of most bands. A natural increase in the Raman shift was observed for most bands assigned to the same vibrations (the smallest shift in the spectrum is characteristic of sidorenkite, an intermediate - of bonshtedtite, and the largest - of bradleyite).&lt;/p&gt;&lt;p&gt;We propose the following algorithm for the diagnosis of carbonophosphates:&lt;/p&gt;&lt;ul&gt;&lt;li&gt;Checking minerals for belonging to the group of carbonophosphates by the main bands and the characteristic profile of the spectrum;&lt;/li&gt; &lt;li&gt;Testing the hypothesis that the mineral of question is bradleyite based on the analysis of the estimated shift of the main bands;&lt;/li&gt; &lt;li&gt;Diagnosis of a mineral species by peaks located between the main bands;&lt;/li&gt; &lt;li&gt;Validation of the diagnostics by considering the position of the bands at 185&amp;#177;9 cm&lt;sup&gt;-1&lt;/sup&gt;, 208&amp;#177;7 cm&lt;sup&gt;-1&lt;/sup&gt;, 255&amp;#177;5 cm&lt;sup&gt;-1&lt;/sup&gt;, and 725&amp;#177;6 cm&lt;sup&gt;-1&lt;/sup&gt;.&lt;/li&gt; &lt;/ul&gt;&lt;p&gt;The proposed algorithm allows one to perform Raman diagnostics of carbonophosphates in inclusions even in the absence of EPMA data. In the study of carbonatites, kimberlites, and other rocks, the diagnostics of the mineral species of the carbonophosphate group can be important in the petrological aspect.&lt;/p&gt;&lt;p&gt;This research was funded by the Russian Science Foundation, grant number 19-77-10039.&lt;/p&gt;

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