91 research outputs found
The dynamics of the non-heme iron in bacterial reaction centers from Rhodobacter sphaeroides
AbstractWe investigate the dynamical properties of the non-heme iron (NHFe) in His-tagged photosynthetic bacterial reaction centers (RCs) isolated from Rhodobacter (Rb.) sphaeroides. Mössbauer spectroscopy and nuclear inelastic scattering of synchrotron radiation (NIS) were applied to monitor the arrangement and flexibility of the NHFe binding site. In His-tagged RCs, NHFe was stabilized only in a high spin ferrous state. Its hyperfine parameters (IS=1.06±0.01mm/s and QS=2.12±0.01mm/s), and Debye temperature (θD0~167K) are comparable to those detected for the high spin state of NHFe in non-His-tagged RCs. For the first time, pure vibrational modes characteristic of NHFe in a high spin ferrous state are revealed. The vibrational density of states (DOS) shows some maxima between 22 and 33meV, 33 and 42meV, and 53 and 60meV and a very sharp one at 44.5meV. In addition, we observe a large contribution of vibrational modes at low energies. This iron atom is directly connected to the protein matrix via all its ligands, and it is therefore extremely sensitive to the collective motions of the RC protein core. A comparison of the DOS spectra of His-tagged and non-His-tagged RCs from Rb. sphaeroides shows that in the latter case the spectrum was overlapped by the vibrations of the heme iron of residual cytochrome c2, and a low spin state of NHFe in addition to its high spin one. This enabled us to pin-point vibrations characteristic for the low spin state of NHFe
Rapid-FISH – fast and reliable method of detecting common numerical chromosomal aberrations in prenatal diagnosis
Abstract Objective: In recent years, new possibilities of prenatal diagnosis have opened up, due to the development of techniques which guarantee shorter time of obtaining results. One of those methods, called Rapid-FISH (rapid fluorescence in situ hybridization), for detecting numerical aberrations of chromosomes 13, 18, 21, X and Y without culturing, enables to have the results in 2-5 days. The time necessary to obtain fetal karyotype result with the usage of the classical cytogenetic methods is about 2-3 weeks and depends mainly on the culture growth rate. Design: The aim of the study was to evaluate the effectiveness of the Rapid-FISH technique in detecting numerical chromosome aberrations of 13, 21, 18, X and Y in amniocytes’ nuclei from amniotic fluid. Materials and Methods: Rapid-FISH and cytogenetic analysis has been performed for 161 pregnancies in the Department of Genetics at Wroclaw Medical University during years 2005 and 2006. The FISH was performed using AneuVysion kit (Vysis), according to a standard protocol. Results: All normal and abnormal results were confirmed by classical cytogenetic method (GTG banding and karyotyping). Additional chromosomal aberrations, not possible to be detected in FISH, were observed in case of two patients with normal results from FISH analysis. Conclusions: Rapid-FISH is a reliable and fast method for detecting numerical chromosomal aberrations in prenatal diagnosis and should be implemented as a routine diagnostic procedure in pregnancies with high risk of fetal aneuploidy (of chromosomes 13, 18, 21, X i Y)
Effects of second-generation antipsychotics on selected markers of one-carbon metabolism and metabolic syndrome components in first-episode schizophrenia patients
Nonlinear Effects in Osmotic Volume Flows of Electrolyte Solutions through Double-Membrane System
Infobright for analyzing social sciences data
There are considerable challenges in analyzing, interpreting, and reporting word-based social sciences data. Infobright data warehousing technology was used to analyze a typical data set from the social sciences. Infobright was found to require augmentation for analyzing qualitative data provided as short stories by human subjects. A requirements specification for mining data that are subject to interpretation is proposed and left to the Infobright designers to implement should they so choose. Infobright was chosen as a system for implementing the data set because its rough set based intelligence appears to be extensible with moderate effort to implement the data warehousing requirements of word based data. © 2009 Springer-Verlag Berlin Heidelberg
The instrumental method of determination of total phosphorus content in fly ash
Nowelizacja normy PN-EN 450-1:2012 wprowadza liczne zmiany dotyczące
częstotliwości oraz metod badań dla popiołów lotnych stosowanych do
produkcji betonu. Zmiany te dotyczą m.in. oznaczenia całkowitej zawartości
fosforu, który należy oznaczać według ISO 29581-2 – Cement-Test methods.
Part 2: Chemical analysis by X-ray fluorescence (metoda referencyjna).
Dzięki temu, że norma PN-EN 450-1:2012 pozwala na zastosowanie
metod własnych, postanowiono przygotować alternatywną metodę badawczą
oznaczenia całkowitej zawartości fosforu w popiele lotnym. Opracowano
metodę kolorymetryczną wykorzystującą powstawanie barwnego kompleksu
fosforomolibdenianu antymonu, który w reakcji z kwasem askorbinowym
(jako reduktorem) tworzy kompleks błękitu molibdenowego, a zawartość fosforu
wyznacza się spektrofotometrycznie, na podstawie absorbancji kompleksu
przy długości fali 880 nm, przeliczając zgodnie ze wzorem zawartym
w opracowanej instrukcji jako procent masy P2O5.
Przygotowana metoda została doświadczalnie potwierdzona i udokumentowana
na podstawie obiektywnego dowodu, że zostały spełnione wszelkie
aspekty gwarantujące poprawność wyniku.The amendment to the standard PN-EN 450-1:2012 introduces a number
of changes in the frequency and test methods for fly ash used in concrete.
These changes relate, among others to indication of the total phosphorus
content, which should be measured according to ISO 29581-2 – Cement –
Test methods. Part 2: Chemical analysis by X-ray fluorescence (reference
method). Thanks to the PN-EN 450-1:2012 allows the use of own methods,
decided to prepare an alternative test method for determination of total phosphorus
content in fly ash. The developed method is a colorimetric method
utilizing the formation of a colored complex of antimony phosphomolybdate,
which is in reaction with ascorbic acid (as a reductor) forms a complex of
molybdenum blue, and the phosphorus content is determined by spectrophotometry
by the absorbance of the complex at 880 nm, converting in the
format set in the instructions as % by mass of P2O5.
Prepared method was experimentally confirmed and documented on the basis
of impartial evidence, that all aspects ensuring the correctness of the
result were fulfilled
Multi-parametric evaluation of spa waters captured from the south-west of Poland
Wody zdrojowe występują w różnych miejscach na ziemi, jednak Polska to kraj bogaty w ich źródła. Skład chemiczny wód podziemnych zależy od sposobu ich zasilania, właściwości hydrodynamicznych warstwy wodonośnej oraz oddziaływań antropogenicznych. Wody lecznicze mają podwyższony poziom charakterystycznych składników mineralnych, przez co ich odpowiednie proporcje mogą wspomagać leczenie lub eliminować różnego rodzaju schorzenia. W pracy zaprezentowano charakterystykę, skład chemiczny oraz właściwości wybranych wód zdrojowych pochodzących z różnych części południowo-zachodniej Polski. W próbkach wód pobranych z sześciu punktów przeprowadzono ocenę zawartości metali oraz jonów. Otrzymane wyniki porównano do wartości maksymalnych zawartych w Rozporządzeniu Ministra Środowiska [12]. Przekroczone wartości maksymalne zanotowano dla zawartości manganu oraz jonów azotynowych w wodzie pobranej z uzdrowiska Świeradów Zdrój. Analiza wód z pozostałych uzdrowisk nie wykazała przekroczeń maksymalnych wartości określonych przez Ministra Środowiska, ale stężenia wybranych analitów są podwyższone.Spring water waters are found in various places on earth, but Poland is a country rich in their sources. The chemical composition of groundwater depends on the method of their supply, hydrodynamic properties of the aquifer and anthropogenic interactions. Healing waters have an elevated level of characteristic minerals, which allows their proper proportions to support treatment or eliminate various diseases. The work presents the characteristics, chemical composition and properties of selected spa waters from different parts of south-western Poland. In water samples taken from six points, the content of metals and ions was assessed. The obtained results were compared to the maximum values contained in the Regulation of the Minister of the Environment [12]. Exceeded maximum values were noted for the content of manganese and nitrite ions in water taken from the spa Świeradów Zdrój. Analysis of waters from other spas did not show exceedances of the maximum values set by the Minister of the Environment, but the concentrations of selected analytes are increased
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