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In this work, an approach to the calculation of hydrogen bonding enthalpies is proposed. It employs the correlation proposed by M.H. Abraham, establishing the connection between the equilibrium constant (KHB) and acidity (α2H) and basicity (β2H) parameters: log KHB = 7.354 · α2H · β2H − 1.099. Hydrogen bonding enthalpy (ΔHBH) is found using the compensation relationship with Gibbs energy (ΔHBG): ΔHBG = 0.66 · ΔHBH + 2.5 kJ·mol−1. This relationship enables the calculation of the enthalpy, Gibbs energy and entropy of hydrogen bonding. The validity of this approach was tested against 122 experimental hydrogen bonding enthalpies values available from the literature. The root mean square deviation and average deviation equaled 1.6 kJ·mol−1 and 0.5 kJ·mol−1, respectively.

Abstract Objective A comparison between commercial computer screens and DICOM-calibrated medical screens for characterizing anatomy and diagnosing dental pathologies was performed. The aim of this study was to evaluate and compare the ability of each of those screens to identify root apices and widening of the periodontal ligament (PDL) in the posterior maxillary area. Materials and Methods Digital X-ray images of 53 maxillary molar teeth were examined by means of a commercial computer screen and again two months later with a DICOM screen to compare their ability to help identify and diagnose PDL widening and to locate the root apices of those teeth. Results The DICOM screen had a significantly better ability to identify widened PDLs (from 31.4% to 34.8% of the cases compared to 19% to 26.1% for the commercial screens, P

Abstract Objective examination of the influence of chemical composition changes on the ability of sealers to withstand a pull-out test. Materials and methods Fifty distal or palatal canals of extracted teeth were prepared by Dc Taper files. The teeth were divided into five groups: AH Plus, BJM RCS, Total Fill BC,AH Plus Bioceramic and a group with Gutta Percha with no sealer added. Ten days after obturation, each cone was subjected to the “pull-out test” with the Shimadzo Universal Testing Machine until it was torn or removed from the canal. A force to Stroke graph was generated and the maximum vertex of this graph was recorded. The number of times the cone was torn or removed was recorded. Results The amount of force needed to remove or rupture the cone was significantly higher in all sealer groups compared to the AH Plus Bioceramic group. The force needed for the AH Plus group was double that needed for the AH Plus Bioceramic group 4 (1.87 ± 0.53 N vs 0.93 ± 0.48 N, respectively, P

Winter wheat is one of the most important crops in Ukraine, and modern varieties have the potential to produce high yields under favourable conditions. The realisation of the genetic yield potential of a variety is the result of a complex interaction of genotype and environmental variables. In order to find effective sources of resistance, a collection of winter wheat accessions of different ecological and geographical origin was studied. The research was conducted in 2017-2019 in the Right-Bank Forest-Steppe, and the analysis of plant resistance of the winter wheat collection of the National Centre of Plant Genetic Resources of Ukraine was tested against a synthetic infectious background of septoria, brown rust and smut as opposed to the natural background of powdery mildew, leaf yellowing (pyrenophorosis) and other root rot. The collection of 32 varieties was represented by 9 countries, most of them of Ukrainian origin. In the field, on artificial and natural infectious backgrounds, we identified varieties characterised by group resistance to pathogens of major diseases. The studies of adult plant resistance under conditions of infectious natural background and the use of the method of artificial complex infectious background have established that it is possible to investigate and identify sources of resistance to both individual pathogens and a complex of pathogens. As a result, no accessions were found to possess group resistance against the six pathogens presented. The selected varieties, Zdoba Kyivska, Vykhovanka Odeska and Feonia, can be used as sources of group resistance, which allows for excellent breeding efforts leading to the development of resistant wheat varieties. The selected sources are suitable for inclusion in breeding programmes as starting material for the development of modern high-yielding winter durum wheat varieties resistant to diseases and other environmental factors

(1) Background: In this study, the efficacy of cone-beam computed tomography (CBCT) in detecting dental posts was compared to periapical radiography. (2) Methods: A retrospective evaluation of 53 patients’ periapical radiographs and CBCT images was performed. The presence and type of the intra-canal dental post were initially determined on the periapical images (PA) radiographs’ examination and were then compared to the observer’s ability to detect the dental post on a CBCT image. The effect of the post’s type (metal cast or prefabricated) on its detection on CBCT images was determined. (3) Results: 10.5% of teeth that were identified as having a post on a PA radiograph were not identified as having a post on the CBCT examination (p < 0.05). Approximately 17.6% of teeth that were identified as not having a post on a PA radiograph were identified as having a post on the CBCT examination (p < 0.05). Moreover, 16.3% and 50% of teeth with a prefabricated or cast posts on PA radiographs were falsely identified on the CBCT examination, respectively (p < 0.05). (4) Conclusions: A CBCT image is an insufficient tool for the identification of metal prefabricated and cast posts. A PA image is the recommended radiographic tool for achieving information about the post-endodontic restoration status of teeth candidates for endodontic retreatment in patients with a former CBCT scan.

1,3,5-Tris-(α-naphthyl)benzene is an organic non-electrolyte with notable stability of an amorphous phase. Its glassy and supercooled liquid states were previously studied by spectroscopic and calorimetric methods. Despite the continuing interest in its amorphous state and, particularly, vapor-deposited glasses, the thermodynamic parameters of the vaporization of 1,3,5-tris-(α-naphthyl)benzene have not been obtained yet. Likewise, the reliable evaluation of the thermodynamic parameters of fusion below the melting point, required to establish the thermodynamic state of its glass, is still an unsolved problem. In this work, the heat capacities of crystalline and liquid phases, the temperature dependence of the saturated vapor pressures, fusion and vaporization enthalpies were determined using differential and fast scanning calorimetry and were verified using the estimates based on solution calorimetry. The structural features of 1,3,5-tris-(α-naphthyl)benzene are discussed based on the computations performed and the data on the molecular refractivity. The consistency between the values obtained by independent techniques was demonstrated.

ObjectiveSocial isolation is highly common in late life and is associated with devastating mental health and physical outcomes. This study investigated whether components of social isolation (marital status, perceived social support, and interpersonal problems) predict change in depression severity over the course of a brief adherence intervention delivered in a primary care setting.MethodA sample of 189 older adults with major depressive disorder were randomized to either an adherence intervention, "Treatment Initiation Program," or treatment as usual. Marital status, perceived social support and interpersonal problems were assessed at baseline. A mixed-effects regression was used to test whether these factors predicted the change trajectory in depression severity over 24 weeks.ResultsBeing married (F(2,176) = 6.60; p = 0.001), reporting higher perceived social support (F(2,177) = 4.70; p = 0.01), and fewer interpersonal problems (F(2, 176) = 4.34; p = 0.01) predicted lower depression severity on average over the course of 24 weeks.ConclusionSocial variables such as living in partnership, perceiving others as supportive, and reporting few interpersonal problems may reduce older adults' vulnerability to depression and enhance their ability to benefit from treatment. These findings can guide development of interventions that will target these social factors early in treatment to increase efficacy.

Reversed halo sign (RHS) is a radiological feature described as a focal, rounded area of ground-glass opacity surrounded by a ring of consolidation. In this report we describe two unique radiological cases demonstrating diffuse bilateral infiltrates with multiple RHSs in chest CT scans. Both patients were ultimately diagnosed as having tuberculosis (TB) and had been exposed to silica in the past. This report presents for the first time an association between silica exposure and RHS on CT scans among TB patients. It highlights the importance of having a high index of suspicion for TB in similar scenarios.

The article is devoted to the analysis of the changes that are taking place in the global oil refining industry under the influence of the current recession in the world economy. Despite the recovery of the global economy after the pandemic, nevertheless, the risks of an intensification of the geopolitical conflict have led to an unprecedentedly difficult situation in the energy markets. Newly emerging restrictions in international trade, including in the form of sanctions, have led to risks of unstable development of the oil refining industry. In turn, the uncertainty in the dynamics of world oil prices, as shown in the article, as well as the trends in the transition to a low-carbon economy, make it difficult to predict the development of the oil and gas industry, including oil refining. The serious changes observed in the structure of fuel production and consumption in the United States will have a significant impact on the development of the industry under study in the future, where there is already a shortage of refining capacity and unstable dynamics of prices for petroleum products. The introduction of additional capacities in the world oil refining, as noted in the article, will not have a significant positive impact on the oil product markets in the short term.