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2021 ◽  
Vol 25 (4) ◽  
pp. 282-289
Author(s):  
Tatjana Yu. Zotova ◽  
Anastasiya A. Lukanina ◽  
Mikhail L. Blagonravov

Relevance . The study of the daily dynamics of blood pressure in arterial hypertension both on the basis of the daily index and on the basis of the time load is a relevant task, since, these indicators are associated in the literature with stable changes in the neurohumoral regulation of the cardiovascular system in arterial hypertension . The aim of the study was to compare data of the time load in patients with arterial hypertension , depending on the nocturnal blood pressure profile, with integrative indicators of the activity of the cardiovascular system in the form of a Circadian index, a structural point of blood pressure, double product. Materials and Methods. The study included 72 patients who were treated at the City Clinical Hospital No 13 in Moscow and signed a voluntary consent to participate in the research and the processing of personal data. Inclusion criteria: arterial hypertension. Exclusion criteria: metabolic syndrome, secondary forms of arterial hypertension and concomitant pathology. Depending on the daily index (DI10% and DI10%) patients were divided into 2 groups: 1 group (N= 32): patients with arterial hypertension without nocturnal decrease in blood pressure (non-dippers and night-pickers100%); Group 2 (N = 40): patients with arterial hypertension who had a nocturnal decrease in blood pressure (dippers and over dippers 100%). All patients and members of the control group (N=15) underwent daily monitoring of blood pressure (24-hour Arterial Blood Pressure Monitoring). The data were statistically processed to determine the 5% level of significance of differences (p0.05) (Students test). In the comparative analysis of integrative indicators at day and at night, a variance analysis was applied. Results and Discussion . As a result of the study, it was found that the values of Circadian Index for blood pressure vary depending on the type of night decrease in blood pressure and the blood pressure time load, while daily index and structural point of blood pressure remain on the same level as a reflection of the hemodynamic allostasis existing in both groups. Conclusion. Reflection of the allostatic load on hemodynamics is change of values of double product and of the structural point of blood pressure compared with the control group. These changes are not associated with the peculiarities of the nocturnal blood pressure profile in patients with hypertension without metabolic syndrome.


2021 ◽  
Vol 14 (2) ◽  
pp. 402-436
Author(s):  
José Luis Blas Arroyo

Abstract Based on the existence of some structural conflict between Spanish and Catalan in certain points of the syntax, this study tests the hypothesis about the influence of the latter on the distribution of queísmo uses (‘Me alegro que vengas’ [‘I’m glad you come’]) in the Spanish spoken in an eastern peninsular variety in contact with Catalan. Using the tools of comparative sociolinguistics, and the analysis of three corpora of contemporary Spanish, the study exhaustively examines the conditioning of this variable. The starting hypothesis is that the influence of the contact can be inferred from the comparison between different magnitudes derived from a multivariable statistical analysis. In addition to several linguistic and extra-linguistic predictors previously analysed in the literature, we also take into account other factor groups that may be particularly informative about that potential influence. Thus, from a structural point of view, we consider the contrast between: a) conjunctive queísmo in verbal structures, in which the structural conflict with Spanish is more evident (‘me acuerdo (de) que vino con su mujer/em recorde Ø que va vindre amb la seua dona’ [‘I remember that he came with his wife’]; and b) pronominal queísmo in relative sentences, in which the coincidence between both languages is greater (‘el día (en) que nos conocimos / el día (en) què ens vam conéixer’). From an extralinguistic perspective, the incidence of two additional factors is also examined: a) the speech community (without contact (Madrid/Alcalá) vs. in contact (Castellón), and b) the main language of the speakers (Spanish/Catalan-Valencian). The results of several mixed-effect regression analyses performed do not support the hypothesis of contact. The distributional differences between the above-mentioned groups are minimal, and in no case significant. On the other hand, the variation is basically affected by the same structural and non-structural predictors, regardless of the speech community or the ethnolinguistic group examined. Even the few divergences that are observed point in a direction contrary to that expected by the contact hypothesis. The study concludes with some potential explanations about these results and the contrast with other cases of syntactic convergence with Catalan.


2021 ◽  
Vol 13 (4) ◽  
pp. 47-58
Author(s):  
George Catalin CRISTEA ◽  
Adriana STEFAN ◽  
George PELIN ◽  
Cristina-Elisabeta PELIN ◽  
Maria SONMEZ ◽  
...  

This paper presents the results of mechanical and tribological characteristics for two composites: PA6 as matrix and 5% aramid whiskers as additive material and PA6 + 10% aramid whiskers, comparing them to those made of PA6 (polyamide 6). To improve the mechanical and thermal properties of polyamide (PA6), the composites were prepared via the Brabender lab mixer and mould forming under given pressure and temperature conditions. Test specimens made of pure PA6 and PA6 mixed with 5 wt.% and 10 wt.% aramid whiskers were subjected to mechanical tests (three-point bending and impact), thermo–mechanical test (HDT - heat deflection temperature), tribological test (block-on-ring) and analyzed from morpho-structural point of view. Compared to the PA6 samples, the mass concentrations of aramid whiskers improved the HDT deflection temperature values. In the case of samples with 5% aramid whiskers, the absorbed energy increased by 13% and for those with 10% aramid whiskers they increased by 30%. Aramid whiskers-doped materials performed much better on severe tribological testing as compared to PA6 samples. Increasing the deflection temperature, also improved their resistance from a tribological point of view.


2021 ◽  
Vol 54 (6) ◽  
Author(s):  
Giorgia Confalonieri ◽  
Giovanna Vezzalini ◽  
Filippo Quattrini ◽  
Simona Quartieri ◽  
Catherine Dejoie ◽  
...  

Cerium exchange by microporous materials, such as zeolites, has important applications in different fields, for example, rare earth element recovery from waste or catalytic processes. This work investigated the Ce-exchange capacity of zeolite L in three different cationic forms (the as-synthesized K form and Na- and NH4-exchanged ones) from a highly concentrated solution. Chemical analyses and structural investigations allowed determination of the mechanisms involved in the exchanges and give new insights into the interactions occurring between the cations and the zeolite framework. Different cation sites are involved: (i) K present in the original LTL in the cancrinite cage (site KB) cannot be exchanged; (ii) the cations in KD (in the 12-membered ring channel) are always exchanged; while (iii) site KC (in the eight-membered ring channel) is involved only when K+ is substituted by NH4 +, thus promoting a higher exchange rate for NH4 + → K+ than for Na+ → K+. In the Ce-exchanged samples, a new site occupied by Ce appears in the centre of the main channel, accompanied by an increase in the number of and a rearrangement of H2O molecules. In terms of Ce exchange, the three cationic forms behave similarly, from both the chemical and structural point of view (exchanged Ce ranges from 38 to 42% of the pristine cation amount). Beyond the intrinsic structural properties of the zeolite L framework, the Ce exchange seems thus also governed by the water coordination sphere of the cation. Complete Ce recovery from zeolite pores was achieved.


Author(s):  
Elena Pulidori ◽  
Anna Lluveras-Tenorio ◽  
Rita Carosi ◽  
Luca Bernazzani ◽  
Celia Duce ◽  
...  

AbstractThis paper presents the results obtained from the thermal analysis of a set of geomaterials (clays, pyroclastic materials, and industrial recycled materials) to be used as raw materials for the synthesis of geopolymers, specifically designed for the conservation of Cultural Heritage (CH) buildings, particularly in seismic hazard zones such as Sicily. X-ray diffraction and gas volumetric analysis (calcimetry) were applied to this set of raw materials in order to characterize the materials from the chemical and structural point of view. Thermogravimetric analysis (TG), TG coupled to Fourier transform infrared spectroscopy (TG-FTIR), and differential scanning calorimetry were used to characterize their thermal behavior. The statistical treatment of the thermogravimetric data by principal component analysis and hierarchical clustering analysis highlights the direct relation between the thermal data and the material composition that will be exploited for the selection of the best materials to obtain geopolymers specifically designed for the conservation of CH buildings.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Gouming Martens

Syntactic freezing has mainly been approached from a structural point of view, recently though, more cognitive approaches in terms of processing costs have been proposed. One such processing account is the additive account. According to this approach, the freezing effect is best explained as an additive effect of two syntactic processes coming together, rather than being a phenomenon on its own. Another processing account argues that the freezing effect is the result of a prosodic garden path according to which extraction can only take place from a prosodically focused constituent. The current study provides empirical evidence for a less discussed factor contributing to the freezing effect, namely a pragmatic one. The pragmatic account requires frozen sentences to have contextually given referents. If no such referent is present, the sentence becomes less acceptable. The need for such a referent comes from the non- default word order associated with frozen sentences, which often highlights/focuses a certain constituent. Several experiments were run to test the pragmatic account. Based on the results it was concluded that pragmatic factors play a significant role in explaining the apparent freezing effects. Other factors however, seem to contribute to this effect as well since this effect cannot be fully explained in terms of pragmatic factors solely.


2021 ◽  
Author(s):  
Manish Sarkar ◽  
Paul Etheimer ◽  
Soham Saha

COVID-19 is caused by SARS-CoV-2 which has affected nearly 220 million people worldwide and death toll close to 5 million as of present day. The approved vaccines are lifesaving yet temporary solutions to such a devastating pandemic. Viroporins are important players of the viral life cycle of SARS-Cov-2 and one of the primary determinants of its pathogenesis. We studied the two prominent viroporins of SARS-CoV-2 (i) Orf3a and (ii) Envelope (E) protein from a structural point of view. Orf3a has several hotspots of mutations which has been reported in SARS-CoV-2 with respect to SARS-CoV-1. Mutations in SARS-CoV-2 Orf3a channel forming residues enhances the formation of a prominent the inter-subunit channel, which was not present in the SARS-CoV-1 Orf3a. This enhanced structural feature can be correlated with higher channelling activity in SARS-CoV-2 than in SARS-CoV-1. On the other hand, E protein is one of the most conserved protein among the SARS-CoV proteome. We found that the water molecules form networks of electrostatic interactions with the polar residues in the E protein putative wetted condition while no water channel formation was observed in the putative dewetted condition. This aqueous medium mediates the non-selective translocation of cations thus affecting the ionic homeostasis of the host cellular compartments. This ionic imbalance leads to increased inflammatory response in the host cell. Our results shed light into the mechanism of viroporin action, which can be leveraged for the development of antiviral therapeutics. Furthermore, our results corroborate with previously published transcriptomic data from COVID-19 infected lung alveolar cells where inflammatory responses and molecular regulators directly impacted by ion channelling were upregulated. These observations overlap with transcript upregulation observed in diseases having acute lung injury, pulmonary fibrosis and Acute Respiratory Distress Syndrome (ARDS).


Author(s):  
Maia Baramidze

The Tao dialect is one of the southern dialects. The remnants of a dialect, spread across once extensive territory, are now preserved in a number of minor villages of Tao (Eliaskhevi, Tsitleqari, Khevai, Quabagi, Phishnarkhevi, Baslekari, Balkhi, Qvenobani, Balkhibari, Gaghmaqobai, Chevreli), as well as in the village, bordering Tao and Klarjeti – Binati.The Tao Georgian is noteworthy due to many aspects.The abstract looks upon some phraseological units, spread in the Tao Georgian dialect.The phraseological units of the Tao Georgian are diverse both from the semantic and structural point of view.The first component of a phraseological unit in Tao dialect is usually the word ‘eye’, the next ones are mostly often the verbs ‘hold (keep)’ or ‘have’, the meaning of the phrase being ‘appealing, taking to or falling in love’: is aqevr vinme gogoze t’vali k’onebia ki. In addition to the mentioned meanings of ‘keep/hold an eye’, more variations are realized through this expression in Tao dialect, such as ‘jinx or overlook in an evil way’: nonas t’valma dimicira.Somatic phraseological units express pain, having as their second consistent component the verb ‘inflamate’: ik’ kar gevdet’, ak’ t’avi ement’o; clikebi ent’eba. Fainting, connected with grief and distress is expressed by phrases, which have brain as their essential component: esa cevda, c’em kac’ma ckva dimilia, cevda ert’i t’ve ar vxedavdi, imaze imaze ckva cevda; aman ckva dimilia.


Author(s):  
Simona BOICIUC

The paper aims to obtain thin films of nickel and zinc through the magnetron-assisted spraying process and their characterization from a structural point of view, of electrical, optical properties and corrosion resistance. It was found that as the intensity and discharge power increase, changes occur in the structure and properties of the deposited films.


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