25 research outputs found
Lignosulfonate as a byproduct of wood pulp production: A potential precursor for the preparation of functional hybrid materials
Functional hybrid materials based on magnesium lignosulfonate and silica were obtained and characterized. Magnesium lignosulfonate is a common waste product of the wood pulp industry, while silica is a well-known inorganic material with exceptional physicochemical properties. In this study, silicas with a spherical particle shape were synthesized using a sol-gel method and alternatively in a nonpolar medium. Silica was found to improve the thermal and electrokinetic properties of the final products. The resulting lignosulfonate/silica hybrid materials were analyzed with the use of advanced techniques and measuring methods: scanning electron microscopy, a laser diffraction method enabling particle size measurements, Fourier transform infrared spectroscopy, elemental analysis, thermogravimetry, electrophoretic light scattering, zeta potential measurements, low-temperature nitrogen sorption, and colorimetric analysis. The results enabled the hybrid materials to be characterized from the point of view of potential applications in various branches of industry (for example as polymer fillers, electroactive blends and biosorbents). We additionally indicate new methods for the utilization of waste products, a category to which lignosulfonate certainly belongs
Olivopontocerebellar artrophy in MRI spectroscopy : case report
Background: Olivopontocerebellar atrophy (OPCA) is an adult-onset disorder. It may occur in a sporadic or familial form. Case report: We present the case of a 62-year-old man with clinical symptoms of progressive cerebellar ataxia. Conclusions: Radiography presented atrophy of the pons and cerebellum. Clinically the syndrome results in progressive ataxia and bulbar dysfunction. Spectroscopy MR shows decrease in NAA/Cr ratio in cerebellum and pons - typical patterns of atrophy
Prognostic factors in Polish patients with BRCA1-dependent ovarian cancer
Background: Treatment outcomes appear to be better for ovarian cancer (OC) patients carrying the BRCA1/2 germline mutation than for patients with sporadic OC. However, most published data are for North American, British and Jewish populations. There have been very few studies on treatment outcomes in Central and Eastern European patients with OC. The aim of this study was to analyse prognostic factors in Polish patients with BRCA1-dependent OC (BRCA1-OC). Methods: The records of patients with OC treated with surgery and chemotherapy at the Centre of Oncology in Kraków, Poland, between 2004 and 2009 were reviewed. Based on family history, a group of 249 consecutive patients fulfilling the criteria for risk of hereditary OC were selected and tested for the germline BRCA1 mutation. Response to combination therapy (surgery and chemotherapy) in the BRCA1-OC group was assessed based on clinical examination, imaging and serum CA125. Results: Germline BRCA1 mutations were detected in 69 of the 249 patients, but three of these patients failed to complete the study. Finally, 66 patients with BRCA1-OC were included in the study group. The median age of the study patients was 49.5 years. All had undergone primary or interval cytoreductive surgery and chemotherapy. Progression occurred in 48 (72.7 %) of the 66 patients and median time to progression was 20 months. The 5-year overall survival rate in was 43.9 % and median survival time was 32.3 months. On multivariate analysis, the endometrial subtype of OC and serum CA125 < 12.5 U/ml at the end of treatment were independent, positive prognostic factors for 5-year overall survival. Conclusion: Prognostic factors for favourable treatment outcomes in Polish patients with BRCA1-OC do not appear to differ from those in patients with sporadic OC. The incidence of the endometrial subtype of OC was relatively high (34.9 %) among women in the study. This was unexpected and has not been reported previously. This subtype of OC was an independent prognostic factor for favourable treatment outcomes
Preparation and Characterization of Multifunctional Chitin/Lignin Materials
Multifunctional chitin/lignin materials were synthesized. In order to combine mechanical milling of the biopolymers with simultaneous mixing, a centrifugal ball mill was utilized. The resulting materials, differing in terms of the proportions of precursors used, underwent detailed physicochemical and dispersive-morphological analysis. On the basis of FT-IR spectra and results of elemental analysis, the efficiency of the preparation of the materials was determined. The influence of the precursors on the thermal stability of the resulting systems was also evaluated. Zeta potential was determined as a function of pH to describe the electrokinetic stability of aqueous dispersions. This is important for evaluating the utility of the materials and indirectly confirms the effectiveness of the proposed method of synthesis of chitin/lignin products. Measurements were performed to determine basic colorimetric parameters, crucial in the production technology of multiple colored materials. It is expected that chitin/lignin materials will find a wide range of applications (biosorbents, polymer fillers, and electrochemical sensors), as they combine the unique properties of chitin with the specific structural features of lignin to provide a multifunctional material
Dual FRET assay for detecting receptor protein interaction with DNA
We present here a new assay that is based on the idea of the molecular beacon. This assay makes it possible to investigate two proteins interacting with DNA at two binding sites that are close to each other. The effectiveness of the test depends on the exclusive binding of three DNA fragments in the presence of two proteins, and the monitoring of the process depends upon observing the quenching of two independent fluorescence donors. As a model we used the components of the heterodimeric ecdysteroid receptor proteins ultraspiracle (Usp) and ecdysone receptor (EcR) from Drosophila melanogaster and a response element from the promoter of the hsp27 gene. The response element consists of two binding sites (half-sites) for the DNA binding domains (DBDs). We have shown that protein–protein interactions mediate cooperative binding of the ecdysteroid receptor DBDs to a hsp27pal response element. The analysis of the microscopic dissociation constants obtained with the DMB led to the conclusion that there was increased affinity of UspDBD to the 5′ half-site in the presence of EcRDBD when the 3′ half-site was occupied, and increased affinity of EcRDBD to the 3′ half-site when the 5′ half-site was occupied
And Guns, and Butter
The defence industry is one of the few remaining industrial islands in the sea of the deindustrialized Polish economy. Given the need to conduct a creative industrial policy, which has been imposed through membership of the EU common market, as well as the opportunities that emerge as a consequence of the defence modernization programme of the Polish Armed Forces, that potential should be adequately utilized for the purposes defined by the state’s security policy, as well as of the need to rebuild the productive, research and educational potential of the Polish economy. That, in turn, requires not only better procedures (reinstating the government’s committee on defence issues) better cadres, as well as an ability to manage an informal network of interdependent interests of the different sectors of economy and administration.Przemysł zbrojeniowy jest jedną z nielicznych przemysłowych wysepek zdezindustrializowanej gospodarki Polski. Wobec politycznej konieczności prowadzenia kreatywnej polityki przemysłowej w ramach wspólnego rynku Unii Europejskiej, a także szans, jakie daje program modernizacji Sił Zbrojnych RP, potencjał „zbrojeniówki” powinien być odpowiednio wykorzystany zarówno do celów bezpieczeństwa państwa, jak i odbudowania potencjału wytwórczego, badawczo-rozwojowego czy edukacyjnego naszej gospodarki. Powodzenie takiej operacji wymaga jednak dalekosiężnej i przemyślanej polityki Ministerstwa Obrony Narodowej oraz umiejętności jej skoordynowania z politykamiprojektowanymi przez Ministerstwa Gospodarki, Skarbu Państwa i Nauki. To z kolei wymaga nie tylko lepszych procedur (reaktywacja międzyresortowego ciała w rodzaju Komitetu Spraw Obronnych Rady Ministrów), lepszych kadr, ale także umiejętności stworzenia nieformalnych sieciowych powiązań interesów różnych sektorów gospodarki i administracji.
Słowa kluczowe: polityka obronna; polityka przemysłowo-zbrojeniowa; reindustrializacja; koordynacja; technologia; podwójne zastosowanie; bezpieczeństwo dosta
Determination of measurement uncertainty by a Monte Carlo method for an RF power sensor calibration system using a VNA
This work proposes a systematic assessment of measuring type A uncertainty (caused by random errors) used in RF power sensor calibration. To reduce A type uncertainty, several successive measurements are repeated. The uncertainty arises from repeatability errors in connectors caused by changes in their electrical properties during repeated mating. The suitability of the METAS UncLib software was analysed and we concluded that software should be developed to take into account the shape of probability density function (PDF) using a Monte Carlo method (MCM), which was lacking in METAS UncLib. The self-developed software was then tested on an example taken from the literature and the superiority of the MCM over the analytical method (GUM) was confirmed. During the calibration of the RF sensor using a vector network analyzer (VNA), a series of repeated measurements were performed and, after applying our MCM software, it was found that the measurement uncertainties calculated by the MCM method were several times larger than those by the GUM. The reason for this was that the correlation between the measured input quantities was not taken into account. When this was done using a covariance matrix and assuming a normal PDF of the input quantities, the results obtained with the GUM and the MCM converged. Our main objective was to investigate the influence of the PDF shape of the input measurement samples on the measurement uncertainty. Taking more than a dozen measurements is too costly, on the other hand, the small sample size prevents a reliable determination of the PDF shape. Finally, to overcome this inconvenience, we have developed a special method that uses the histograms of standardized input data taken at all measurement frequencies under fixed conditions without disconnecting the connectors, to increasing the total number of results which were needed to create the PDF histograms of input quantities
Removal of lead(II) ions by an adsorption process with the use of an advanced SiO2/lignin biosorbent
We demonstrate here that lignin can be successfully combined with silica to create a multifunctional material with considerable sorption capabilities. Experiments were carried out in which a silica/lignin hybrid was used for the removal of lead(II) ions from water solutions. Adsorption kinetics were also determined and preliminary regeneration tests were performed. The effectiveness of the adsorption process depends on the following parameters: contact time of adsorbent and adsorbate (equilibrium times: 5 min for concentration 25 mg/L, 10 min for 50 and 75 mg/L, 60 min for 100 mg/L), pH (optimal pH = 5) and adsorbent mass. The kinetics of the adsorption of lead(II) ions on the SiO2/lignin biosorbent are best described by a pseudo-second-order model. Adsorption isotherms of lead(II) ions were also determined. The experimental data were found to be in agreement with the Langmuir model, and the maximal sorption capacity of the adsorbent with respect to lead(II) was 89.02 mg/g
Hypernetworks build Implicit Neural Representations of Sounds
Implicit Neural Representations (INRs) are nowadays used to represent
multimedia signals across various real-life applications, including image
super-resolution, image compression, or 3D rendering. Existing methods that
leverage INRs are predominantly focused on visual data, as their application to
other modalities, such as audio, is nontrivial due to the inductive biases
present in architectural attributes of image-based INR models. To address this
limitation, we introduce HyperSound, the first meta-learning approach to
produce INRs for audio samples that leverages hypernetworks to generalize
beyond samples observed in training. Our approach reconstructs audio samples
with quality comparable to other state-of-the-art models and provides a viable
alternative to contemporary sound representations used in deep neural networks
for audio processing, such as spectrograms.Comment: ECML202