Repozytorium Uniwersytetu Śląskiego RE-BUŚ
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Vapor-Deposited Thin Films: Studying Crystallization and α-relaxation Dynamics of the Molecular Drug Celecoxib
No full textCrystallization is one of the major challenges in using glassy solids for
technological applications. Considering pharmaceutical drugs, maintaining a stable
amorphous form is highly desirable for improved solubility. Glasses prepared by the
physical vapor deposition technique got attention because they possess very high stability,
taking thousands of years for an ordinary glass to achieve. In this work, we have
investigated the effect of reducing film thickness on the α-relaxation dynamics and
crystallization tendency of vapor-deposited films of celecoxib (CXB), a pharmaceutical
substance. We have scrutinized its crystallization behavior above and below the glasstransition
temperature (Tg). Even though vapor deposition of CXB cannot inhibit
crystallization completely, we found a significant decrease in the crystallization rate with decreasing film thickness. Finally, we have
observed striking differences in relaxation dynamics of vapor-deposited thin films above the Tg compared to spin-coated counterparts
of the same thickness
Changes in Species and Functional Diversity of the Herb Layer of Riparian Forest despite Six Decades of Strict Protection
No full textThe herb layer of temperate forests contributes to long-term forest ecosystem functioning
and provisioning of ecosystem services. Therefore, a thorough understanding of its dynamics in the
face of environmental changes is essential. This paper focuses on the species and functional diversity
of the herb layer of riparian forests to verify how these two community components changed over
time and under strict protection. The understory vegetation was surveyed on 42 semi-permanent
plots in three time periods between 1960 and 2020. The overall pattern in vegetation changes that
related to species richness and diversity, functional structure, and habitat conditions was analyzed
using ordination and permutation techniques. We found significant changes in species composition
and the functional structure of herbaceous vegetation over the last six decades. Forests were
enriched with nutrient-demanding and alien species. A significant increase in functional diversity
and the proportion of species with high SLA and canopy height was also observed, whereas changes
in habitat conditions were insignificant. The observed trends indicate that the strict protection of
forest communities within small and isolated reserves does not fully protect their species composition.
Forest reserves should be surrounded by unmanaged forests and spatially connected to allow
species mobility
Dielectric and electric properties of Ba0.996La0.004Ti0.999O3 ceramics doped with europium and hafnium ions
Get PDFLanthanum-modified BaTiO3 electroceramic materials have superior dielectric and piezoelectric
properties. Ba0.996La0.004Ti0.999O3 (BLT4) seems to be a serious candidate for ultracondensator
applications. This manuscript describes the results of hafnium and europium modification of BLT 4
ceramics. The pure and doped ceramic materials were synthesized by the conventional mixed oxide
method. The microstructure of obtained samples was examined by scanning electron microscope. The
investigations reveal strong correlations between the presence of admixture and the grain size, which
was especially visible in the case of the hafnium dopant. The frequency and temperature dielectric
characteristics measurements revealed a decrease in electric permittivity. Moreover, the impedance
spectroscopy investigations showed severe changes in grains and grain-boundary resistivity, which
was connected with changes in electric conductivity
Sugar decorated star-shaped (co)polymerswith resveratrol-based core – physicochemicaland biological properties
Get PDFStar-shaped glycopolymers due to the attractive combination of the physicochemical, morphological, self-assembly properties along with biological activity have gained increased attention as innovative agents in novel cancer therapies. Unfortunately, the production of these highly desirable biomaterials remains a challenge in modern macromolecular chemistry. The main reason for that is the low polymerizability of ionic glycomonomers originated from their steric congestion and the occurrence of ionic interactions that generally negatively influence the polymerization progress and hinder controllable reaction pathway. In this work, the new ionic sugar monomer was (co)polymerized for the first time via Activator Generated by Electron Transfer Atom Transfer Radical Polymerization (AGET ATRP) using a three-arm resveratrol-based core to obtain star-like (co)polymers. The obtained products were examined in terms of their physicochemical properties and morphology. Aside from the synthesis of these new glycopolymers, also a thorough description of their thermal properties, ability to self-assembly, the formation of stable superstructures was studied in detail. It was found that examined (co)polymers did not show any heterogeneities and phase separation, while their variation of glass transition temperature (Tg) was strictly related to the change in the number of glycomonomer. Also, the stability and shapes of formed superstructures strictly depend on their composition and topology. Finally, we have shown that synthesized carbohydrate-based polymers revealed high antiproliferative activity against several cancer cell lines (i.e., breast, colon, glioma, and lung cancer). The cytotoxic activity was particularly observed for star-shaped polymers that were systematically enhanced with the growing concentration of amine moieties and molecular weight. The results presented herein suggest that synthesized star-shaped glyco(co)polymers are promising as drug or gene carriers in anticancer therapies or anti-tumor agents, depending on their cytotoxicity.
Graphical abstrac
Electrical conductivity and dielectric relaxation in Ag1-xLixNbO3
Get PDFThe broadband electrical properties of Ag1xLixNbO3 (ALNx) ceramics (x 0.1) together
with AgNbO3 (AN) crystals were studied over a wide temperature interval of 20–800 K. For ALNx
with x 0.05, a very diffused ferroelectric phase transition was observed. The position of the dielectric
permittivity maximum in this phase transition is strongly frequency-dependent and is described
well by the Vogel–Fulcher law. The freezing temperature decreases when the lithium concentration
increases. Below the ferroelectric phase transition temperature, the dielectric dispersion is mainly
caused by ferroelectric domain dynamics. Moreover, for ALN3 and ALN5 ceramics at very low
temperatures (below 100 K), behavior typical of dipolar glasses is observed. At higher temperatures
(above 650 K for ALN5), electrical conductivity effects become important. The DC conductivity
increases with temperature according to the Arhenius law and the activation energy is highest in
the antiferroelectric phase. Moreover, the activation energy is strongly dependent on the lithium
concentration and it is greatest when x = 0.02
Wprowadzenie
Get PDF"Publikacja, którą oddajemy w Państwa ręce, jest ekwiwalentem VII Ogólnopolskiego
Sympozjum Naukowego Neurodydaktyki. Zdajemy sobie sprawę, że nie zastąpi
tego, czym jest dla uczestników bezpośrednie spotkanie. Z naszych zeszłorocznych doświadczeń
wynika, że nie jest tego w stanie dać także namiastka w postaci formy zdalnej.
Dlatego w tym roku zdecydowaliśmy się na taką formę intelektualnego spotkania.
Od początku istnienia Sympozjum naszą intencją było zbliżenie do siebie praktyków
edukacji oraz przedstawicieli tych dziedzin nauki, którzy proces ten widzą jako podmiot
swoich refl eksji i badań. Nie chodziło jedynie o wymianę doświadczeń i wiedzy, lecz
także o tworzenie przestrzeni wspólnego działania i wzajemnych inspiracji. Pretekstem,
który miał do tego zbliżenia posłużyć, była silnie wkraczająca w obszar dydaktyki neurobiologia
z jej fascynującymi odkryciami. Szybko okazało się, że sama wiedza o ludzkim
mózgu nie przynosi rozwiązań konkretnych problemów, z jakimi zderza się edukacja, jeśli
nie zostanie włączona w szerszy kontekst. Neurodydaktyka jest użytecznym i cennym narzędziem
interpretacji, nie jest jednak zbiorem gotowych rozwiązań. Wyjaśnia, dlaczego
pewne zjawiska są takie, a nie inne, wskazuje granice naszych możliwości i odpowiedzialności,
ale nie jest sposobem na usprawiedliwienie wyborów, jakich dokonujemy. Te pozostają
poza granicami naukowej jednoznaczności." (fragm.
Characteristics of natural background radiation in the GIG Experimental Mine ‘Barbara’, Poland
Get PDFUnderground locations can be used in various ways for scientific and economic purposes. One of the main factors influencing the safety level in the underground mine workings is natural radioactivity. The article presents research carried out on the natural radioactivity in shallow mine workings at the GIG Experimental Mine ‘Barbara’. The description of the natural radiation includes radon determination in the air, in situ gamma spectrometry, neutron flux measurements, and laboratory measurements of 226,228Ra, 40K, and 234,238U isotopes using gamma and alpha spectrometry techniques. In the measurement chamber at the depth 46 m (122 m w.e.) in the sandstone layer, the photon flux registered at the 7–3150 keV energy range is equal to 17.6 ± 1.9 cm−2s−1, the gamma-ray dose rate is 0.200 ± 0.029 µSv/h, and the thermal neutron flux is equal to (8.6 ± 1.1) × 10−6 cm−2s−1. After closing the measurement chamber and turning off ventilation, a significant ingrowth of 222Rn content was observed, reaching the value of 4040 ± 150 Bq/m3. An increased gamma-ray flux and thermal neutron flux were observed in the investigated location
miR172 Regulates WUS during Somatic Embryogenesis in Arabidopsis via AP2
No full textIn plants, the embryogenic transition of somatic cells requires the reprogramming of the
cell transcriptome, which is under the control of genetic and epigenetic factors. Correspondingly,
the extensive modulation of genes encoding transcription factors and miRNAs has been indicated
as controlling the induction of somatic embryogenesis in Arabidopsis and other plants. Among
the MIRNAs that have a differential expression during somatic embryogenesis, members of the
MIRNA172 gene family have been identified, which implies a role of miR172 in controlling the
embryogenic transition in Arabidopsis. In the present study, we found a disturbed expression of
both MIRNA172 and candidate miR172-target genes, including AP2, TOE1, TOE2, TOE3, SMZ and
SNZ, that negatively affected the embryogenic response of transgenic explants. Next, we examined
the role of AP2 in the miR172-mediated mechanism that controls the embryogenic response. We
found some evidence that by controlling AP2, miR172 might repress the WUS that has an important
function in embryogenic induction. We showed that the mechanism of the miR172-AP2-controlled
repression of WUS involves histone acetylation. We observed the upregulation of the WUS transcripts
in an embryogenic culture that was overexpressing AP2 and treated with trichostatin A (TSA),
which is an inhibitor of HDAC histone deacetylases. The increased expression of the WUS gene
in the embryogenic culture of the hdac mutants further confirmed the role of histone acetylation in
WUS control during somatic embryogenesis. A chromatin-immunoprecipitation analysis provided
evidence about the contribution of HDA6/19-mediated histone deacetylation to AP2-controlled WUS
repression during embryogenic induction. The upstream regulatory elements of the miR172-AP2-
WUS pathway might involve the miR156-controlled SPL9/SPL10, which control the level of mature
miR172 in an embryogenic culture
KS0 meson production in inelastic p+p interactions at 158 GeV /c beam momentum measured by NA61/SHINE at the CERN SPS
Get PDFA. Acharya, H. Adhikary, K. K. Allison, N. Amin, E. V. Andronov, T.Antic, V. Babkin, M. Baszczyk, S. Bhosale, A. Blondel, M. Bogomilov, Y. Bondar, A. Brandin, A.Bravar, W.Brylinski, J. Brzychczyk, M. Buryakov, O. Busygina, A. Bzdak, H. Cherif, M. Cirkovic, M. Csanad, J. Cybowska, T. Czopowicz, A. Damyanova, N. Davis, M. Deliyergiyev, M. Deveaux, A. Dmitriev,W. Dominik, P. Dorosz, J. Dumarchez, R. Engel, G. A. Feofilov, L. Fields, Z. Fodor, A.Garibov, M.Gazdzicki, O. Golosov, V. Golovatyuk, M. Golubeva, K. Grebieszkow, F. Guber, A. Haesler, S. N. Igolkin, S. Ilieva, A. Ivashkin, S. R. Johnson, K. Kadija, N. Kargin, E. Kashirin, M. Kiełbowicz, V. A. Kireyeu, V. Klochkov, V. I. Kolesnikov, D.Kolev, A. Korzenev, V. N. Kovalenko, B. Kozłowski, A. Krasnoperov, W. Kucewicz, M. Kuich, A. Kurepin, D. Larsen, A. László, T. V. Lazareva, K. Łojek, V. V. Lyubushkin, M. Mackowiak-Pawłowska, Z. Majka, B. Maksiak, A. I. Malakhov, A. Marcinek, A. D. Marino, K.Marton, H.-J. Mathes, T. Matulewicz, V.Matveev, G. L. Melkumov, A. O. Merzlaya, B. Messerly, Ł.Mik, S. Morozov, Y. Nagai, M. Naskret, V. Ozvenchuk, O. Panova, V. Paolone, O. Petukhov, I. Pidhurskyi, R. Płaneta, P. Podlaski, B. A. Popov, B. Porfy, M. Posiadała-Zezula, D. S. Prokhorova, D. Pszczel, J. Puzovic, M. Ravonel, D. Röhrich, E. Rondio, B. T. Rumberger, M. Rumyantsev, A. Rustamov, M. Rybczynski, A. Rybicki, S. Sadhu, A. Sadovsky, I. Selyuzhenkov, A. Yu. Seryakov, P. Seyboth, M. Słodkowski, P. Staszel, G. Stefanek, J. Stepaniak, M. Strikhanov, H. Ströbele, T. Šuša, A. Taranenko, A. Tefelska, D. Tefelski, V. Tereshchenko, A.Toia, R. Tsenov, L. Turko, M. Unger, D. Uzhva, F. F. Valiev, D. Veberiˇc, V. V. Vechernin, A. Wickremasinghe, O. Wyszyński, A. Zaitsev, E. D. Zimmerman, R. ZwaskaThe production of K0
S mesons in inelastic p+p
collisions at beam momentum 158 GeV/c (
√
sNN =
17.3 GeV) was measured with the NA61/SHINE spectrometer
at the CERN Super Proton Synchrotron. Doubledifferential
distributions were obtained in transversemomentum
and rapidity. The mean multiplicity of K0
S was determined
to be 0.162±0.001(stat.)±0.011(sys.). The results
on K0
S production are compared with model predictions
(EPOS 1.99, SMASH 2.0, PHSD and UrQMD 3.4 models)
as well as with published world data
Pre-operative high-dose-rate brachytherapy in early-stage cervical cancer: long-term single-center results
Get PDFPurpose: The aim of the study was to report the outcomes of pre-operative high-dose-rate brachytherapy (pHDRBT),
followed by hysterectomy in patients with early cervical cancer.
Material and methods: From January, 1998 to December, 2003, 113 women with IB1, IB2, and IIA1 cervical cancer
(according to International Federation of Gynecology and Obstetrics [FIGO] 2018) were treated with pHDR-BT, and
6 to 8 weeks later followed by radical hysterectomy. Patients found to have positive lymph nodes, residual cervical
cancer, involved parametria, or lymphovascular space invasion (LVSI) received post-operative adjuvant therapy.
Results: Post-operatively, 81.4% of patients had a complete response to pHDR-BT in the cervix, and 18.6% had
residual cervical cancer. Failures occurred in 11/113 (9.7%) patients (all were stage IIA1), with pelvic recurrences in
5/113 (4.4%) and distant metastasis (DM) in 6/113 (5.3%). The 5- and 10-year disease-free survival (DFS) rates were
100% for IB1 and IB2, and 86.4% and 81.3% for IIA1, respectively. Lymph node involvement and/or residual cervical
cancer correlated with worse DFS. Two vesicovaginal fistulas were observed (one in a patient treated only with pHDRBT
and one in a woman, who underwent adjuvant external-beam radiotherapy [EBRT]). Two rectovaginal fistulas and
one case of proctitis were observed in patients treated with adjuvant EBRT.
Conclusions: pHDR-BT in early cervical cancer is well-tolerated and effective in sterilizing tumor cells in the cervix.
The growing number of publications in this area may help define an optimal therapeutic scheme, but randomized trials
are required to determine the best candidates for this treatment modality.
In our opinion, cervical cancer patients with FIGO stage IIA1 are not good candidates for pHDR-BT, and could be
given this treatment only after rigorous selection, including assessment with state-of-the-art imaging, due to higher
probability of treatment failure