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Aluminum garnets display exceptional adaptability in incorporating mismatching elements, thereby facilitating the synthesis of novel materials with tailored properties. This study explored Ce3+-doped Tb3Al5−xScxO12 crystals (where x ranges from 0.5 to 3.0), revealing a novel approach to control luminescence and photoconversion through atomic size mismatch engineering. Raman spectroscopy confirmed the coexistence of garnet and perovskite phases, with Sc substitution significantly influencing the garnet lattice and induced A1g mode softening up to Sc concentration x = 2.0. The Sc atoms controlled sub-eutectic inclusion formation, creating efficient light scattering centers and unveiling a compositional threshold for octahedral site saturation. This modulation enabled the control of energy transfer dynamics between Ce3+ and Tb3+ ions, enhancing luminescence and mitigating quenching. The Sc admixing process regulated luminous efficacy (LE), color rendering index (CRI), and correlated color temperature (CCT), with adjustments in CRI from 68 to 84 and CCT from 3545 K to 12,958 K. The Ce3+-doped Tb3Al5−xScxO12 crystal (where x = 2.0) achieved the highest LE of 114.6 lm/W and emitted light at a CCT of 4942 K, similar to daylight white. This approach enables the design and development of functional materials with tailored optical properties applicable to lighting technology, persistent phosphors, scintillators, and storage phosphors. [ABSTRACT FROM AUTHOR]

Knowledge on the Eemian (MIS 5e) fauna of Poland is based on vertebrate remains from 16 open-air localities and 8 cave sites. Considering the short period of time covered by MIS 5e, the amount of data is surprisingly large. There is still an ongoing debate on whether the age of some assemblages is Eemian, latest Saalian or even earliest Weichselian. There are faunal assemblages or stratigraphically isolated finds with some disputable evidence. The full picture of the evolution of the Eemian vertebrate fauna in the present-day territory of Poland is still far from being complete. The finds of various groups of vertebrates (fishes, amphibians, reptiles, birds and mammals) from the Eemian Interglacial of Poland are analysed in terms of their environmental preferences. A number of thermophilic species or forms which preferred temperate climate conditions are known from this period. Among them, Clethrionomys glareolus, Glis glis, Meles meles, Martes martes, Lynx lynx, Felis silvestris, Sus scrofa, Palaeoloxodon antiquus, and Stephanorhinus kirchbergensis indicate a forest environment. The presence of species that preferred more open environments (Cricetus cricetus, Mammuthus primigenius, Coelodonta antiquitatis, and Equus ferus) is also recorded for the Eemian Interglacial of Poland. Characteristic was the presence of the large broad-toothed and flat-headed Ursus arctos taubachensis, which additionally often outnumbered remains of Ursus spelaeus sensu lato in the contemporary layers. The Eemian vertebrate fauna of Poland consisted of about 150 species (representing 61 genera and 26 families), most of which were recorded earlier from other localities of this age in central and eastern Europe. [ABSTRACT FROM AUTHOR]

β-Hydroxy sulfones are important in organic synthesis. The simplest method of β-hydroxy sulfones synthesis is the hydrogenation of β-keto sulfones. Herein, we report the reducing properties of alkyl aluminum compounds R3Al (R = Et, i-Bu, n-Bu, t-Bu and n-Hex); i-Bu2AlH; Et2AlCl and EtAlCl2 in the hydrogenation of β-keto sulfones. The compounds i-Bu2AlH, i-Bu3Al and Et3Al are the at best reducing agents of β-keto sulfones to β-hydroxy sulfones. In reactions of β-keto sulfones with aluminum trialkyls, hydroalumination products with β-hydroxy sulfone ligands [R2AlOC(C6H5)CH2S(O)2(p-R1C6H4]n [where n = 1,2; 2aa: R = i-Bu, R1 = CH3; 2ab: R = i-Bu, R1 = Cl; 2ba: R = Et, R1 = CH3; 2bb: R = Et, R1 = Cl] and {[Et2AlOC(C6H5)CH2S(O)2(p-ClC6H4]∙Et3Al}n3bb were obtained. These complexes in the solid state have a dimeric structure, while in solutions, they appear as equilibrium monomer–dimer mixtures. The hydrolysis of both the isolated 2aa, 2ab, 2ba, 2bb and 3bb and the postreaction mixtures quantitatively leads to pure racemic β-hydroxy sulfones. Hydroalumination reaction of β-keto sulfones with alkyl aluminum compounds and subsequent hydrolysis of the complexes is a simple and very efficient method of β-hydroxy sulfones synthesis. [ABSTRACT FROM AUTHOR]

The structures and interactions in four new hydrates of substituted piperidines have been studied using X-ray crystallography and quantum chemistry. The piperidine ring substitution leads to a significant reduction in the number of hydrates compared with the parent amine, with 4-methylpiperidine yielding a hemihydrate and a trihydrate; 4-chloropiperidine a monohydrate and a trihydrate, (where the architecture is similar to 4-methylpiperidine trihydrate). Despite many attempts, it did not prove possible to crystallize hydrates with higher molar amine : water ratios. Therefore, trihydrates are probably the most hydrated crystals to be obtained at ambient pressure for both amines. Both trihydrates create identical water layers of the L4(6)5(7)6(8) type and the main structural difference is the arrangement of hydrogen bonds between water layers and amines. Despite this, both trihydrates have the same melting temperature (263 K) and as supported by lattice energy calculations. Chlorine⋯chlorine contacts have no significant impact on the stabilization of the 4-chloropiperidine monohydrate or the 4-chloropiperidine trihydrate. Periodic DFT-D3 calculations show that the energies of the water layers are identical in both cases, and the summed hydrogen bond energies (although arranged differently) are similar. Moreover, in the case of trihydrates, which have a 2-D topology of water⋯water interactions, it is possible to perform DFT calculations for separate layers and to determine the contribution of those interaction energies to the cohesive energy of the whole crystals. [ABSTRACT FROM AUTHOR]

t‐Butyl derivatives play a significant role in the organometallic chemistry of group 13 metals. It was shown on the basis of reactions of t‐Bu3Al·OEt2 with [p‐RC6H4S(O)2C(H)2C(Ph) = O] (where R = CH3, Cl) β‐keto sulfones that the structure of the reaction products depends on the purity of the aluminum compound used. In the reactions, in addition to the expected complexes [p‐RC6H4S(O2)C(H) = C (Ph)‐OAl(t‐Bu)2] [where R = CH3 (2); R = Cl (4)] possessing β‐keto sulfone ligands, complexes with β‐hydroxy sulfone ligands [p‐RC6H4S(O2)C(H)2‐C (Ph)‐OAl(t‐Bu)2] [where R = CH3 (1); R = Cl (3)] were formed. Compounds 1 and 3 were the result of the hydroalumination reaction of the β‐keto sulfone ligands with t‐Bu2AlH, which is an impurity of t‐Bu3Al. These compounds are obtained, for the first time, as intermediate products in the hydrogenation reaction of β‐keto sulfones. In this work, during t‐Bu3Al·OEt2 production t‐Bu2AlH·OEt2 formed as a by‐product. Re‐examination of reaction conditions of AlCl3 with t‐BuMgCl resulted in a control of the t‐Bu2AlH·OEt2 by‐product content in t‐Bu3Al·OEt2. [ABSTRACT FROM AUTHOR]

Although cave bear remains have been described since the end of 18th century, recent discoveries and methods provide new knowledge about the typical representative of Pleistocene megafauna, which did not survive the Last Glacial Maximum. Genetic studies supplemented by morphometric analyses showed that this mammal differentiated in the Late Pleistocene into two main forms called Ursus spelaeus and U. ingressus. The latter is regarded more expansive and replaced the native U. spelaeus in some areas of Western Europe. Taking into account the differences between these bears, it is interesting to determine if these forms became extinct at different or similar times. Therefore, we assessed their extinction times, applying seven methods using 205 dated records of cave bear ascribed to these two forms. The average extinction time of U. spelaeus was about 25,600 cal. yr BP (Before Present) and of U. ingressus about 24,800 cal. yr BP. The estimations showed that that U. ingressus could survive up to ca. 1,000 years longer than its relative U. spelaeus. The longer survival of the former could be related to its greater morphological variability and better adaptation to arid continental environments, as well as a stronger tendency to occasional omnivory. Both bears became extinct within the coldest phase of the last glacial period, Greenland Stadial 3, which implies that climate cooling was the main factor of their extinction. The climate deterioration decreased vegetation productivity, and could also have had negative consequences on the prolonged hibernation period when the bears were more susceptible to the activity of humans and predators. [ABSTRACT FROM AUTHOR]

Complexes containing aminophenolate ligands are considered as very efficient initiators of ring-opening polymerization (ROP). Our systematic studies of the reactions of two selected aminophenols, 2-[( p-tolylamino)methyl]-4-(2,4,4-trimethylpentan-2-yl)phenol (L'H2) and 2-cyclohexylaminomethyl-4-methylphenol (L″H2), with alkyl compounds of aluminium, gallium and zinc resulted in the formation of a variety of products depending on the type of metallic centre and alkyl groups bonded to metal atoms. New trinuclear aluminium complexes (Me5Al3(L′)2 ( 1) and Me5Al3(L″)2 ( 2)), monomeric aluminium ( tBu2Al(L'H) ( 3) and tBu2Al(L″H) ( 5)) and gallium ( tBu2Ga(L'H) ( 4) and tBu2Ga(L″H) ( 6)) compounds, and dinuclear gallium (Et2Ga(L″H)·Et3Ga ( 7)) and zinc ( tBuZn(L″H)]2 ( 8)) complexes were isolated and characterized. The molecular and crystal structures of 7 and 8 were determined on the basis of an X-ray diffraction study. Polymerization tests showed that only three complexes ( 6- 8) had activity in the ROP of ε-caprolactone, whereas 1- 5 were inactive in ROP. [ABSTRACT FROM AUTHOR]

2-Mercapto-1,3-benzothiazole (mbztH) may act as a chelating or bridging ligand. In this study, reactions of mbztH with Me3Ga and Me3In were examined. The products were characterized by NMR spectroscopy, elemental analyses, melting point, and molecular weight determinations. Formation of mononuclear chelating complexes Me2M(mbzt) (M = Ga, In) was observed in solutions. Crystallization of Me2M(mbzt) yielded uncommon non-symmetrical dinuclear complexes Me4M2(mbzt)2, in which one metal is bonded to two sulfurs and the other to two nitrogens. [ABSTRACT FROM PUBLISHER]

Recent palaeogenetic studies indicate a highly dynamic history in collared lemmings ( Dicrostonyx spp.), with several demographical changes linked to climatic fluctuations that took place during the last glaciation. At the western range margin of D. torquatus, these changes were characterized by a series of local extinctions and recolonizations. However, it is unclear whether this pattern represents a local phenomenon, possibly driven by ecological edge effects, or a global phenomenon that took place across large geographical scales. To address this, we explored the palaeogenetic history of the collared lemming using a next-generation sequencing approach for pooled mitochondrial DNA amplicons. Sequences were obtained from over 300 fossil remains sampled across Eurasia and two sites in North America. We identified five mitochondrial lineages of D. torquatus that succeeded each other through time across Europe and western Russia, indicating a history of repeated population extinctions and recolonizations, most likely from eastern Russia, during the last 50 000 years. The observation of repeated extinctions across such a vast geographical range indicates large-scale changes in the steppe-tundra environment in western Eurasia during the last glaciation. All Holocene samples, from across the species' entire range, belonged to only one of the five mitochondrial lineages. Thus, extant D. torquatus populations only harbour a small fraction of the total genetic diversity that existed across different stages of the Late Pleistocene. In North American samples, haplotypes belonging to both D. groenlandicus and D. richardsoni were recovered from a Late Pleistocene site in south-western Canada. This suggests that D. groenlandicus had a more southern and D. richardsoni a more northern glacial distribution than previously thought. This study provides significant insights into the population dynamics of a small mammal at a large geographical scale and reveals a rather complex demographical history, which could have had bottom-up effects in the Late Pleistocene steppe-tundra ecosystem. [ABSTRACT FROM AUTHOR]

Surgical and endovascular revascularization of ischemic legs in patients with peripheral arterial disease (PAD) can damage the arterial wall (endothelial and smooth muscle cells). Hemostatic factors released during endothelial dysfunction can lead to restenosis. 1. Determination of selected endothelial hemostatic factors in PAD patients and a reference group. 2. Prospective observation of new restenosis appearance in PAD patients after endovascular revascularization. 3. Comparison of selected endothelial hemostatic factors between non-restenotic and restenotic PAD patients. 150 PAD patients after endovascular revascularization - 90 men and 60 women, aged 44-88 (mean 65.5) years - were examined. During one-year observation after the revascularization procedures in 38 PAD patients restenosis occurred, when blood samples were also collected. The reference group consisted of 53 healthy persons - 44 men and 9 women, aged 20-56 years. Blood was drawn in the morning into 3.2% sodium citrate at a ratio of 9:1. Tissue factor (TF), tissue factor pathway inhibitor (TFPI), thrombomodulin (TM), von Willebrand factor (vWF) and tissue plasminogen activator (t-PA) were measured in plasma with commercial tests using the enzyme immunoassay. In the plasma of PAD patients after revascularization, the concentrations of TF and vWF were significantly higher, TM lower, TFPI and t-PA similar compared to the reference group. Six months after revascularization the level of TF had increased and vWF had significantly decreased. The endothelial hemostatic factors before and after restenosis did not significantly differ except TF, which after restenosis was higher. Increased TF and vWF levels in PAD patients indicate arterial endothelial cell damage, by atherosclerotic and revascularization processes. In PAD patients with restenosis compared to these patients before restenosis the determined endothelial hemostatic factors, except TF level, did not significantly differ. Perhaps TF participates in restenosis formation. [ABSTRACT FROM AUTHOR]

Spirituality has remained a controversial subject matter of psychological research. In spite of this fact, the volume of research grows alongside the development of civilization processes in the Western world. Mostly, these are analyses of spirituality in the substantial approach, particularly that recognizing spirituality as what the research subjects consider it to be. The views of psychologists of interest in the present analysis can be divided into: overt and hidden ones. The first kind includes concepts of philosophical, psychoanalytic, and humanistic origins (usually not subjected to operationalization); the second kind are those whose authors were not in need of recognizing them as theories of spirituality; nevertheless, they seem to have much in common with spirituality. The proposed solution is spirituality as the process of a unique transformation whose outcome is a more or less successful coping with an existential situation. Since it is possible to distinguish provisionally two types of these situations: one of an ultimate character (transience), and one of a non-ultimate (the existential limitations are more or less harmful); likewise there are two types of possible transformation. In both cases, the transformation is a self-creation unique for a particular kind of an existential situation. The understanding of spirituality as a transformation allows for its operationalization through measuring this experience assumed here to be a marker of the feeling of sacredness. One can measure this experience before a particular situation takes place as well as after the period considered the endpoint of coping with this situation occurs. Spirituality - the transcendence of limitations - is a process occurring within a unique existential context. At the end of the article, the features of a spiritual transformation have been described in order to show a wider account of the process. [ABSTRACT FROM AUTHOR]

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