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In this paper, we have investigated the molecular dynamics of the associating polymer, poly(mercaptopropyl)methylsiloxane (PMMS), at high pressure (up to p ∼ 505 MPa) by means of broadband dielectric spectroscopy. Previous studies revealed that PMMS exhibits two dielectric relaxation processes observed above the glass transition temperature related, most likely, to either the mobility within self-assemblies or the sub-Rouse mode (α′-slower process) and segmental (α-faster process) dynamics, whereas mechanical measurements revealed only the presence of terminal and segmental relaxations [Tarnacka et al. Macromolecules 2020, 53 (22), 10225−10233]. In order to determine the origin of the dielectric α′-process, further high-pressure experiments were performed. It was found that the timescale separation between relaxation times of segmental (α) and α′-processes is invariant to the compression, and activation volume calculated for both kinds of motions is comparable. These dynamical features are characteristic of the chain relaxation (called usually normal mode) found in type-A polymers. However, because mechanical data excluded identification of the slow dielectric relaxation as normal mode, we assigned it as the sub-Rouse process. This assignment is in the line with previous studies on poly(methylphenyl)siloxane. Further density functional theory computations revealed that the detection of the relatively strong sub-Rouse process is most likely possible due to the presence of a highly polar side group (thiol, −SH, moiety) that gives a strong contribution to dipole moment along the main polymer backbone. Additionally, we demonstrated that the pressure coefficient of the glass transition temperature, dTg/dp, in PMMS is one of the smallest among those reported to date for various polymers (dTg/dp = 156 K/GPa). This quite surprising finding was assigned to the specific interactions formed by the thiol group. Finally, it should be emphasized that high-pressure experiments turned out to be the key element to identify the sub- Rouse mode in dielectric spectraa process that might provide important information about the chain dynamics in polysiloxanes. However, to finally prove this hypothesis, further studies are required to discard the eventual possibility that the slow mode is somehow related to the nanoscopic organization in PMMS.

In this paper, several experimental techniques [X-ray diffraction, differential scanning calorimetry (DSC), thermogravimetry, Fourier transform infrared spectroscopy, and broad-band dielectric spectroscopy] have been applied to characterize the structural and thermal properties, H-bonding pattern, and molecular dynamics of amorphous bosentan (BOS) obtained by vitrification and cryomilling of the monohydrate crystalline form of this drug. Samples prepared by these two methods were found to be similar with regard to their internal structure, H-bonding scheme, and structural (α) dynamics in the supercooled liquid state. However, based on the analysis of α-relaxation times (dielectric measurements) predicted for temperatures below the glass-transition temperature (Tg), as well as DSC thermograms, it was concluded that the cryoground sample is more aged (and probably more physically stable) compared to the vitrified one. Interestingly, such differences in physical properties turned out to be reflected in the lower intrinsic dissolution rate of BOS obtained by cryomilling (in the first 15 min of dissolution test) in comparison to the vitrified drug. Furthermore, we showed that cryogrinding of the crystalline BOS monohydrate leads to the formation of a nearly anhydrous amorphous sample. This finding, different from that reported by Megarry et al. [Carbohydr. Res.2011, 346, 1061−106421492830] for trehalose (TRE), was revealed on the basis of infrared and thermal measurements. Finally, two various hypotheses explaining water removal upon cryomilling have been discussed in the manuscript.

In this work, we employed broad-band dielectric spectroscopy to determine the solubility limits of nimesulide in the Kollidon VA64 matrix at ambient and elevated pressure conditions. Our studies confirmed that the solubility of the drug in the polymer matrix decreases with increasing pressure, and molecular dynamics controls the process of recrystallization of the excess of amorphous nimesulide from the supersaturated drug–polymer solution. More precisely, recrystallization initiated at a certain structural relaxation time of the sample stops when a molecular mobility different from the initial one is reached, regardless of the temperature and pressure conditions. Finally, based on the presented results, one can conclude that by transposing vertically the results obtained at elevated pressures, one can obtain the solubility limit values corresponding to low temperatures. This approach was validated by the comparison of the experimentally determined points with the theoretically obtained values based on the Flory–Huggins theory.

The article represents the next part of the periodical publications of the Department of Economic Research in the field of cost analysis of the Polish international freight transport companies. It summarises and makes comparative assessments of the average unit costs of these companies for the 2019 in relation to the results of the previous period. The survey involved carriers operating on the Eastern markets. The article presents the statistical characteristics of the entities surveyed, taking into account their size, determined based on the number of the fleet’s heavy goods vehicles operated. It also shows how, the average costs of one vehicle-kilometre (veh-km) of mileage for a truck above 12.0 Mg GVW, are shaped, according to the size of the companies and taking into account the destinations of transport. The generic costs structure of the companies examined, has also been analysed. Presented in the tabular and graphic form is the evolution of unit costs for both 2019 and the whole 2009-2019 period.

The article represents the next part of the periodical publications of the Department of Economic Research in the field of cost analysis of the Polish international freight transport companies. It summarises and makes comparative assessments of the average unit costs of these companies for 2019 in relation to the results of the previous period. The survey involved both, the carriers operating on the eastern markets and in the European Union countries. The article presents statistical characteristics of the companies surveyed, taking into account their size, determined, based on the number of the fleet’s heavy goods vehicles being operated. It also shows how the average costs of a single vehicle-kilometre (veh-km) of mileage, for a truck above 12.0 Mg GVW are shaped, according to the size of the companies and taking into account the direction of transport (EU countries). The generic structure of the costs of the companies examined has been analysed. The evolution of unit costs for both 2019 and the whole period 2009-2018 were presented in tabular and graphic form.

Herein, we investigated the molecular dynamics as well as intramolecular interactions in two primary monohydroxy alcohols (MA), 2-ethyl-1-hexanol (2EHOH) and n-butanol (nBOH), by means of broad-band dielectric (BDS) and Fourier transform infrared (FTIR) spectroscopy. The modeling data obtained from dielectric studies within the Rubinstein approach [Macromolecules2013, 46, 7525−7541] originally developed to describe the dynamical properties of self-assembling macromolecules allowed us to calculate the energy barrier (Ea) of dissociation from the temperature dependences of relaxation times of Debye and structural processes. We found Ea ∼ 19.4 ± 0.8 and 5.3 ± 0.4 kJ/mol for the former and latter systems, respectively. On the other hand, FTIR data analyzed within the van’t Hoff relationship yielded the energy barriers for dissociation Ea ∼ 20.3 ± 2.1 and 12.4 ± 1.6 kJ/mol for 2EHOH and nBOH, respectively. Hence, there was almost a perfect agreement between the values of Ea estimated from dielectric and FTIR studies for the 2EHOH, while some notable discrepancy was noted for the second alcohol. A quite significant difference in the activation barrier of dissociation indicates that there are probably supramolecular clusters of varying geometry or a ring-chain-like equilibrium is strongly affected in both alcohols. Nevertheless, our analysis showed that the association/dissociation processes undergoing within nanoassociates are one of the main factors underlying the molecular origin of the Debye process, supporting the transient chain model.

Herein, broadband dielectric (BDS) and Fourier transform infrared spectroscopy (FTIR), together with differential scanning calorimetry (DSC) and X-ray diffraction (XRD), were applied to study the molecular dynamics, molecular interactions as well as physical stability of an amorphous Active Pharmaceutical Ingredient (API)-probucol (PRO)-infiltrated into anodic aluminum oxide (AAO) membranes of pore size, d ~ 10-160 nm. Interestingly, the behavior of examined substance strongly depends on the applied thermal protocol. Remarkably, for the first time, we observed that the structural dynamics of the slowly cooled PRO under confinement is significantly enhanced when compared to thatofthe quenched material. This unusual behavior was interpreted as a result of surface-induced effects (including the formation of well-resolved interfacial H-bonded layer and adsorption-desorption processes near the interface) that are magnified by the extremely high sensitivity to density fluctuation of studied PRO, reflected in the enormous pressure coefficient of the glass transition temperature dTg/dp = 427 K/GPa. In fact, FTIR investigations revealed that PRO tends to self-associate under confinement and forms a strongly bonded interfacial layer, which controls the variation in the structural dynamics of core molecules. Finally, we observed that the tendency to crystallize of confined API is reduced with respect to the bulk, even though the critical size of PRO nuclei (rc ~ 3 nm) is significantly lower than the smallest examined pore size. Nevertheless, after few weeks of storage, the investigated substance crystallized in larger pores, while it remained stable in the nanochannels of d = 10 nm. A combination of XRD and DSC measurements indicated that the infiltrated PRO forms two polymorphs, the stable form I (dominating in bulk) and unstable form II (prevailing under confinement). That means that porous matrices might be used to obtain and maintain prolonged stability of unstable polymorphic forms of API.

In this study, we report the acid-catalyzed and high pressure assisted ring-opening polymerization (ROP) of g-butyrolactone (GBL). The use of a dually-catalyzed approach combining an external physical factor and internal catalyst (trifluoromethanesulfonic acid (TfOH) or p-toluenesulfonic acid (PTSA)) enforced ROP of GBL, which is considered as hardly polymerizable monomer still remaining a challenge for the modern polymer chemistry. The experiments performed at various thermodynamic conditions (T ¼ 278–323 K and p ¼ 700–1500 MPa) clearly showed that the high pressure supported polymerization process led to obtaining well-defined macromolecules of better parameters (Mn ¼ 2200–9700 g mol 1; Đ ¼ 1.05–1.46) than those previously reported. Furthermore, the parabolic-like dependence of both the molecular weight (MW) and the yield of obtained polymers on variation in temperature and pressure at either isobaric or isothermal conditions was also noticed, allowing the determination of optimal conditions for the polymerization process. However, most importantly, this strategy allowed to significantly reduce the reaction time (just 3 h at room temperature) and increase the yield of obtained polymers (up to 0.62 gPGBL/gGBL). Moreover, despite using a strongly acidic catalyst, synthesized polymers remained non-toxic and biocompatible, as proven by the cytotoxicity test we performed in further analysis. Additional investigation (including MALDI-TOF measurements) showed that the catalyst selection affected not only MW and yield but also the linear/cyclic form content in obtained macromolecules. These findings show the way to tune the properties of PGBL and obtain polymer suitable for application in the biomedical industry.

The impact of the chain length or dispersity of polymers in controlling the crystallization of amorphous active pharmaceutical ingredients (APIs) has been discussed for a long time. However, because of the weak control of these parameters in the majority of macromolecules used in pharmaceutical formulations, the abovementioned topic is poorly understood. Herein, four acetylated oligosaccharides, maltose (acMAL), raffinose (acRAF), stachyose (acSTA), and α-cyclodextrin (ac-α-CD) of growing chain lengths and different topologies (linear vs cyclic), mimicking the growing backbone of the polymer, were selected to probe the influence of these structural factors on the crystallization of naproxen (NAP)an API that does not vitrify regardless of the cooling rate applied in our experiment. It was found that in equimolar systems composed of NAP and linear acetylated oligosaccharides, the progress and activation barrier for crystallization are dependent on the molecular weight of the excipient despite the fact that results of Fourier transform infrared studies indicated that there is no difference in the interaction pattern between measured samples. On the other hand, complementary dielectric, calorimetric, and X-ray diffraction data clearly demonstrated that NAP mixed with ac-α-CD (cyclic saccharide) does not tend to crystallize even in the system with a much higher content of APIs. To explain this interesting finding, we have carried out further density functional theory computations, which revealed that incorporation of NAP into the cavity of ac- α-CD is hardly possible because this state is of much higher energy (up to 80 kJ/mol) with respect to the one where the API is located outside of the saccharide torus. Hence, although at the moment, it is very difficult to explain the much stronger impact of the cyclic saccharide on the suppression of crystallization and enhanced stability of NAP with respect to the linear carbohydrates, our studies clearly showed that the chain length and the topology of the excipient play a significant role in controlling the crystallization of this API.

Dielectric studies under various temperature (T) and pressure (p) conditions on five active pharmaceutical ingredients (APIs) with antifungal properties-itraconazole (ITZ), posaconazole (POS), terconazole (TER), ketoconazole (KET), and fluconazole (FLU)-were carried out. We have thoroughly studied the connection between the pressure coefficient of the glass transition temperature (dTg/dp) and the activation volume of both relaxation modes (ΔVα, ΔVδ/α') with respect to the molecular weight (Mw) or molar volume (Vm) in these systems. Besides, high pressure data revealed that the time scale separation between α- and δ- or α'-processes increases with pressure in ITZ and TER. What is more, the activation entropy, which is a measure of cooperativity, calculated from the Eyring model for the secondary (β)-relaxation in ITZ and POS, increased and decreased, respectively, in the compressed samples. To understand these peculiar results, we have carried out X-ray diffraction (XRD) measurements on the pressure-densified glasses and found that pressure may induce frustration in molecular organization and destroy the medium-range order while enhancing the short-range correlations between molecules. This finding allowed us to conclude that varying molecular spatial arrangement is responsible for the extraordinary dynamical behavior of ITZ, POS, and TER at high pressure.

Background: Human milk, in addition to nutrients, contains many biologically active substances including immunoglobulins, growth factors, cytokines, and a diverse population of somatic cells. Breast milk involves no risk of allergy, contains antibodies, and contains factors such as epidermal growth factor (EGF) and erythropoietin, which may promote the growth and repair of skin cells. The discovery of stem cells and the HAMLET complex in breast milk has led to increased interest in human milk as a natural medicine. Aim of the study: The aim of the study was to identify the effect of topical application of breast milk on the separation time of the umbilical cord stump in newborns. Case report: This paper presents the case of a patient who decided to treat her child’s umbilical cord stump with colostrum/breast milk because her two older children had experienced long umbilical stump separation times. As a result of this treatment, separation of the stump occurred 90 hours after labor. There were no abnormalities in the construction of the navel, complications, or separation disorders of the umbilical cord stump. Conclusion: This research demonstrates that colostrum/mother’s milk was used as an easy, cheap, effective, and natural method of umbilical cord care.

Herein we show that the nanostructured interface obtained via modulation of the pore size has a strong impact on the segmental and chain dynamics of two poly(propylene glycol) (PPG) derivatives with various molecular weights (Mn = 4000 g/mol and Mn = 2000 g/mol). In fact, a significant acceleration of the dynamics was observed for PPG infiltrated into ordinary alumina templates (Dp = 36 nm), while bulklike behavior was found for samples incorporated into membranes of modulated diameter (19 nm < Dp < 28 nm). We demostrated that the modulation-induced roughness reduces surface interactions of polymer chains near the interface with respect to the ones adsorbed to the ordinary nanochannels. Interestingly, this effect is noted despite the enhanced wettability of PPG in the latter system. Consequently, as a result of weaker H-bonding surface interactions, the conformation of segments seems to locally mimic the bulk arrangement, leading to bulklike dynamics, highlighting the crucial impact of the interface on the overall behavior of confined materials.

Objectives The aim of the study was assessment of the quality of life of patients infected with HIV. A short version of the WHOQOL-BREF questionnaire, developed by the World Health Organization, was used, which allows simultaneous evaluation of the quality of life in somatic, social, environmental and psychological spheres, and an author-constructed questionnaire. Material and methods The study group included 105 patients (x males, y females) infected with HIV. The quality of life was assessed using the short version of the WHOQOL-BREF questionnaire supplemented with an author-constructed questionnaire, which consisted of 21 closed questions. Results The WHOQOL-BREF questionnaire and authorconstructed questionnaire are reliable tools for the assessment of the quality of life in adults. The results obtained show the good quality of life of patients infected with HIV. Acceptance of own illness and permanent employment are the basic factors affecting the quality of life of HIV infected patients. Conclusions 1. The perceived state of the quality of life strongly depends on many factors, such as physical and family conditions and the attitude towards the patient. 2. Positive attitude and acceptance of one’s own illness has a great impact on further treatment and quality of life. 3. Support and assistance from the loved ones increases the sense of security of infected people and improves their quality of life. 4. The problem of discrimination and stigmatization still affects patients infected with HIV, resulting from insufficient knowledge in Polish society.

Rheumatoid arthritis is a chronic inflammatory disease leading to disability, reduced quality of life, and severe depressive symptoms. Theoretical models and research emphasize the importance of cognitive factors such as illness-related beliefs and cognitive appraisals in the process of adapting to life with a chronic disease. Objectives: The aim of this study was to analyze the role of age, disease duration, and cognitive factors in the level of acceptance of life with rheumatoid arthritis and determine the factors responsible for short-term (one week) changes without the use of interventions. We also assessed differences in predictors between rheumatoid arthritis, vascular diseases, and diabetes. Methods: Data were collected using a panel study. The first part of the analysis included 83 participants who declared a medical diagnosis of rheumatoid arthritis. In the second part of the analysis, in addition to people with rheumatoid arthritis (69 participants), two control groups were also included: diabetes (n = 26) and vascular disease (n = 26). The analysis examined basic sociodemographic and clinical data, cognitive appraisals, illness-related beliefs, and acceptance of living with the disease twice in one week. Results: The relationship between age and levels of acceptance of living with the disease was cubic, but the groups distinguished based on age and disease duration did not differ in terms of the analyzed variables. Cognitive appraisals (both baseline and changes over one week) were responsible for changes in acceptance of living with the disease, although other variables (sociodemographic, clinical, and illness-related beliefs) also played a role. The predictors of change in acceptance of living with the disease differed between analyzed diagnoses. Conclusions: Cognitive factors are an important aspect of the adaptation process to living with an illness. Potential clinical applications and future directions of research are discussed.

The nature of hydrogen bond (HB) interactions is still far from being understood despite intense experimental and theoretical studies on this subject carried out by the leading research centers. In this paper, by a combination of unique high-pressure infrared, dielectric and volumetric data, the intramolecular dynamics of hydroxyl moieties (which provides direct information about Hbonds) was studied along various isolines, i.e., isotherms, isobars, isochrones, and isochores, in a simple monohydroxy alcohol (2-ethyl-1-hexanol). This allowed us to discover that the temperature controls the intermolecular hydrogen bonds, which then affect the intramolecular dynamics of O-H units. Although the role of density fluctuations gets stronger as temperature rises. We also demonstrated a clear connection between the intra- and intermolecular dynamics of the associating liquid at high pressure. The data reported herein open a new perspective to explore this important aspect of the glass transition phenomenon and understand H-bonding interactions at varying thermodynamic conditions.

The study was carried out on alcohol-preferring male Wistar rats. The following drugs were repeatedly (28×) administered: acamprosate (500 mg/kg, p.o.), naltrexone (0.1 mg/kg, i.p), and Pueraria lobata (kudzu) root extract (KU) (500 mg/kg, p.o.) and its isoflavones: daidzin (40 mg/kg, p.o.) and puerarin (150 mg/kg, p.o.). Their effects on a voluntary alcohol intake were assessed. KU and alcohol were also given for 9 days in an experiment on alcohol tolerance development. Finally, total and active ghrelin levels in peripheral blood serum were measured by ELISA method. Acamprosate, naltrexone, daidzin, and puerarin, reducing the alcohol intake, caused an increase in both forms of ghrelin levels. On the contrary, though KU inhibited the alcohol intake and alcohol tolerance development, it reduced ghrelin levels in alcohol-preferring rats. The changes of ghrelin concentration could play a role as an indicator of the currently used drugs. The other effect on the KU-induced shift in ghrelin levels in the presence of alcohol requires further detailed study.

In this work, we examined the effect of the length of alkyl chain attached to the benzene ring on the self-assembling phenomena for a series of phenyl alcohol (PhA) derivatives, from phenylmethanol (benzyl alcohol) to 7-phenyl-1-heptanol, by means of X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared (FTIR) spectroscopy, and Broadband Dielectric Spectroscopy (BDS) methods. XRD data in the reciprocal and real spaces showed a gradual increase in the local order with the elongation of the alkyl chain. However, the position and full width at half maximum of the main diffraction peak exhibited a non-systematic behavior. To better understand this fact, PhAs were subjected to FTIR spectroscopic studies. These investigations revealed that the association degree and the activation energy of dissociation increase as the alkyl chain length grows. On the other hand, BDS data showed a non-monotonic variation in the Kirkwood correlation factor with increasing length of the alkyl chain, indicating a competition between interactions of the non-polar and polar parts of the molecules in the studied PhAs. Finally, it was also found that the molar surface entropy for PhAs increases with the number of methylene groups, approaching values reported for alkanes, which indicates suppression of the surface order for PhAs with a long alkyl chain. This variability of the various parameters as a function of the length of the side chain shows that the interplay between soft interactions has a strong impact on the local structure and intra and intermolecular dynamics of the studied PhAs.

In this paper, broadband dielectric spectroscopy (BDS) has been applied to study the molecular dynamics and crystallization kinetics of the antihyperlipidemic active pharmaceutical ingredient (API), gemfibrozil (GEM), as well as its deuterated (dGEM) and methylated (metGEM) derivatives, characterized by different types and strengths of intermolecular interactions. Moreover, calorimetric and infrared measurements have been carried out to characterize the thermal properties of examined samples and to probe a change in the H-bonding pattern in GEM, respectively. We found that the dielectric spectra of all examined compounds, collected below the glass transition temperature (Tg), reveal the presence of two secondary relaxations (β, γ). According to the coupling model (CM) predictions, it was assumed that the slower process (β) is of JG type, whereas the faster one (γ) has an intramolecular origin. Interestingly, the extensive crystallization kinetics measurements performed after applying two paths, i.e., the standard procedure (cooling and subsequently heating up to the appropriate temperature, Tc), as well as annealing at two temperatures in the vicinity of Tg and further heating up to Tc, showed that the annealing increases the crystallization rate in the case of native API, while the thermal history of the sample has no significant impact on the pace of this process in the two derivatives of GEM. Analysis of the dielectric strength (Δe) of the α-process during annealing, together with the results of Fourier transform infrared spectroscopy (FTIR) measurements, suggested that the reorganization within dimeric structures formed between the GEM molecules is responsible for the observed behavior. Importantly, our results differ from those obtained by Tominaka et al. (Tominaka, S.; Kawakami, K.; Fukushima, M.; Miyazaki, A.Physical Stabilization of Pharmaceutical Glasses Based on Hydrogen Bond Reorganization under Sub-Tg Temperature Mol. Pharm. 2017 14 264 273 10.1021/acs.molpharmaceut.6b00866.), who demonstrated that the sub-Tg annealing of ritonavir (RTV), which is able to form extensive supramolecular hydrogen bonds, protects this active substance against crystallization. Therefore, based on these contradictory reports, one can hypothesize that materials forming H-bonded structures, characterized by varying architecture, may behave differently after annealing in the vicinity of the glass transition temperature.

Infrared and dielectric spectroscopy, X-ray diffraction, and density functional theory computations have been used to study the hydrogen-bonding pattern, molecular dynamics, internal structure, and dipole moment distribution in 2-ethyl-1-hexanol, 2-ethyl-1-hexylamine, 2-ethyl-1-hexanethiol, and 1-phenyl-2-butanol. Dielectric investigations revealed that Kirkwood–Frohlich correlation factor is much larger or lower than the unity in the vicinity of the glass transition, dependent on the compound. It indicates that change in the functionality of the H-bonding moiety influences the architecture of the supramolecular nanoassemblies. Further thorough experimental and theoretical considerations confirmed this hypothesis. Moreover, it was found that not the strength of hydrogen bonds itself, but the diverse population of nanoassociates, their size, and the spatial organization of the molecules in clusters have a strong influence on the appearance/absence as well as the intensity of the Debye relaxation. The resul...

In this paper, we have analyzed structural, thermal, and dynamical properties of four azole antifungals: itraconazole (ITZ), posaconazole (POS), terconazole (TER) and ketoconazole (KET), differing mainly in the length of the rod-like backbone and slightly in side groups. Our investigations clearly demonstrated that the changes in the chemical structure result in a different ability to form the medium-range order (MRO) and variation in thermal and dynamical properties of these pharmaceuticals. Direct comparison of the diffractograms collected for glassy and crystalline materials indicated that the MRO observed in the former phases is related to maintaining the local molecular arrangement of the crystal structure. Moreover, it was shown that once the MRO-related diffraction peaks appear, additional mobility (δ- or α' relaxation), slower than the structural (α)-process, is also detected in dielectric spectra. This new mode is connected to the motions within supramolecular nanoaggregates. Detailed analysis of dielectric and calorimetric data also revealed that the variation in the internal structure and MRO of the examined pharmaceuticals have an impact on the glass transition temperature (Tg) shape of the α-process, isobaric fragility, molecular dynamics in the glassy state and number of dynamically correlated molecules. These findings could be helpful in an understanding the influence of different types of intermolecular MRO on the properties of substances having a similar chemical backbone.

Broadband dielectric spectroscopy (BDS), combined with the X-ray diffraction (XRD) and Fourier transform infrared (FTIR) techniques, was used to study the dynamics of the primary (α) relaxation process and slow mode (SM), as well as structural properties and intermolecular interactions, in the methyl-, isopropyl-, hexyl-, and benzyl derivative of a well-known pharmaceutical, ibuprofen (IBU). Unexpectedly, the XRD and FTIR methods revealed the formation of medium-range ordering together with some molecular organization, which probably leads to the creation of small aggregates at the scale of several microns at lower temperatures. Moreover, high pressure dielectric experiments revealed that the SM (observed in the ambient pressure data) is not detected in the loss spectra of compressed IBU esters, which is consistent with the results reported previously for propylene carbonate and dioxolane derivatives. This finding can be interpreted as connected to either the comparable time scale of the structural dynamics and slow mode or suppression of the motions responsible for the latter process at elevated pressure. Additionally, it was found that the pressure coefficient of the glass transition temperature (dTg/dp) and activation volume (ΔV) change with molecular weight (Mw) in a non-monotonic way. It might be related to various chemical structures, conformations, and intermolecular interactions, as well as different architecture of supramolecular aggregates in the investigated compounds.

In Poland every year, about 600,000 cars are processed by the vehicle dismantling stations, which entails the necessity of utilizing a significant mass of the waste. Entrepreneurs running the disassembling stations are required to obtain a 95% recovery rate and 85% recycling of the weight of vehicles brought into the company during the year. The article presents the results of the eco-balance analysis of utilizing waste from end-of-life vehicles (ELV). The calculations were carried out following the assumptions of the LCA method, based on the ReCiPe2016 procedure. The potential level of environmental impacts is analyzed in 23 environmental categories, included in three groups, defining effects on human health, ecosystems, and resources. The results were presented as environmental points [Pt], which reflect the potential level of environ-mental burdens exerted by the analyzed object. The limits of the tested system include utilization pro-cesses of the waste from vehicles. One end-of-life vehicle was assumed as a functional unit. Particular attention has been paid to the emissions into the air that adversely affects human health and climate change. The results of the analysis showed that the properly conducted car utilization process brings environmental benefits above all in terms related to human health.

In this paper, we report comprehensive studies on the molecular dynamics of a series of poly(propylene glycol) (PPG) derivatives characterized by three different terminal groups and various molecul...

Different experimental techniques were applied to study thermal and structural properties, strength of H-bonds, possible keto-enol tautomerism and molecular dynamics at various thermodynamic conditions in the H-bonded active substance, curcumin (CRM). Dielectric measurements revealed dynamical features of examined compound that are uncharacteristic for the associated systems. This includes enormously large pressure coefficient of the glass transition temperature and prominent drop of the fragility with compression. Simultaneously, the shape of α-process slightly broadened at elevated pressures. Infrared investigations demonstrated that this effect is related to the variation in the population of H-bonds. Moreover, we studied the changes in the structural and dynamical properties of the glasses prepared upon cooling of the melt (ordinary glass, OG) and the one obtained after compression of CRM in the liquid phase and decompression at T = 293 K (dense glass, DG). Interestingly, during the aging of the latter sample, a clear shift of the β-relaxation towards higher frequencies was noted. This unexpected result indicated that the density of DG is probably getting smaller with time. Complementary X-ray diffraction experiments confirmed this supposition. Additionally, they showed that in DG there are traces of polymorph II of CRM that has a higher density than initial crystals (polymorph I). Finally, infrared studies demonstrated that H-bond pattern in DG is slightly different with respect to OG. Furthermore, Raman investigations suggested that probably keto-enol tautomerism might be shifted towards diketo form in the glass obtained at high compression. Our investigations are very interesting in the context of better understanding of the behavior of associated systems at high compression as well as provide a better insight into dynamics of higher density glasses produced at elevated pressures.

In this paper, we explored the influence of both the variation in the molecular weight (Mn = ∼400, 2000, 4000 g/mol) and the terminal groups (hydroxyl, amino, and methoxy) on the molecular dynamics of poly(propylene glycols) confined within anodic aluminum oxide membranes of different pore diameters. All confined samples revealed the presence of two glass transition temperatures related to the vitrification of two, core and interfacial, fractions of polymers. As found, the glass transition temperature of PPG adsorbed on the pore walls increases with a decrease in polymer Mn and scales with the H-bonding ability of a given material. Surprisingly, the glass transition temperature of the core macromolecules decreases with respect to the bulk sample with increasing Mn. To gain insight into the observed quite unexpected anti-correlated behavior of both Tg values, we performed the additional contact angle and surface tension measurements together with the annealing experiments. As shown, there were no differenc...

The behavior of the low- and high-molecular weight glass formers confined in nanoporous templates remains an unsolved puzzle despite the intensive long-term studies in this matter. Special effort is taken to understand the enhancement of segmental or structural dynamics and the depression of the glass-transition temperatures, Tgs in materials infiltrated in pores of the nanometric size. In this paper, we have analyzed dielectric, calorimetric, and contact angle data collected for various systems to determine which factors are responsible for these effects. It turned out that with increasing interfacial energy, molecules attached to the pore walls (interfacial layer) vitrify at higher temperatures. Moreover, the dynamics of core molecules starts to deviate from bulk-like behavior. Therefore, a greater depression of the glass-transition temperature, Tg, of this fraction of molecules is noted. Also, it was found that the sensitivity of structural dynamics to the density fluctuations, quantified by the pressu...

In this paper, the molecular dynamics and thermal properties of representative acetylated linear and cyclic oligosaccharides: acTRE, acRAF, acSTA, ac-α-CD, ac-β-CD, ac-γ-CD, have been investigated by using broadband dielectric spectroscopy and differential scanning calorimetry. We found that there are marked differences in the dynamics of the structural and secondary relaxation processes in both groups of materials. Just to mention a variation in the distribution of the structural relaxation times as well as different evolutions of the glass transition temperature (Tg) and fragility (m) versus molecular weight (Mw), which seem to be affected by the shape of the molecule, strain in the carbohydrate ring and mobility of side acetyl moieties.

Modified oligosaccharides with cyclic topology seem to be promising excipients for the preparation of Amorphous Solid Dispersions (ASDs), especially with those Active Pharmaceutical Ingredients (APIs), which have a strong crystallization tendency from the amorphous/glassy state. Herein, the usefulness of two acetylated cyclodextrins (ac-α-CD and ac-β-CD) with various molecular weights (M

Crowdfunding to stosunkowo nowa i dynamicznie rozwijająca się forma finansowania różnego rodzaju innowacyjnych projektów. Dane pokazują, że crowdfunding to przykład źródła finansowania o sporym znaczeniu dla wielu przedsiębiorstw, szczególnie w początkowej fazie ich rozwoju. Celem pracy jest ocena crowdfundingu w Polsce jako alternatywnego źródła finansowania poprzez zaprezentowanie najefektywniejszej platformy crowdfundingowej dla innowacyjnego produktu turystycznego. Wybrana metoda badawcza polegała na analizie porównawczej platform crowdfundingowych w Polsce. Analiza ta nie pozwoliła wyodrębnić jednego typu platformy, najchętniej stosowanego do finansowania społecznościowego w specyficznym produkcie turystycznym na terenie miasta Krakowa. Jednak udowodniono, że crowdfunding to forma odpowiednia do finansowania projektów innowacyjnych, zwłaszcza start-upów o podwyższonym poziomie ryzyka.

10-Alkylthiocolchicines have been obtained and characterized by spectroscopic methods and their biological activities as: cytotoxic, anti-inflammatory and analgesic activities have been tested. Cytotoxic activity against SKOV-3 ovarian cell line for 10-alkylthiocolchicine analogues was reported and tested compounds showed to be more active than commonly used doxorubicin. Some of tested C-10 alkylthiolated colchicines have been found to exhibit cytotoxicity at levels comparable to that of the natural product—colchicine. 10-Methylthiocolchicine has IC50 = 8 nM and 10-ethylthiocolchicine has IC50 = 47 nM in comparison to colchicine IC50 = 37 nM. Moreover for 10-alkylthioderivatives apoptosis test, cyclin B1 and cell cycle tests were performed. 10-n-Butylthiocolchicine was tested for anti-inflammatory and analgesic activities it showed to produce analgesic rather than anti-inflammatory effect.