Bolus dynamic computed tomography in the evaluation of pulmonary sequestration

Three cases of pulmonary sequestration evaluated by bolus dynamic computed tomography are described. The computed tomography appearance and the differential diagnosis are discussed. It is important to recognize the advantages of the bolus dynamic technique in the evaluation of pulmonary sequestration as it may eliminate the need for further studies.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26560/1/0000099.pd

Interaction of cylindrical polymer brushes in dilute and semi-dilute solution

We present a systematic study of flexible cylindrical brush-shaped macromolecules in a good solvent by small-angle neutron scattering (SANS), static light scattering (SLS), and by dynamic light scattering (DLS) in dilute and semi-dilute solution. The SLS and SANS data extrapolated to infinite dilution lead to the shape of the polymer that can be modeled in terms of a worm-like chain with a contour length of 380 nm and a persistence length of 17.5 nm. SANS data taken at higher polymer concentration were evaluated by using the polymer reference interaction site model (PRISM). We find that the persistence length reduce from 17.5 nm at infinite dilution to 5.3 nm at the highest concentration (volume fraction 0.038). This is comparable with the decrease of the persistence length in semi-dilute concentration predicted theoretically for polyelectrolytes. This finding reveals a softening of stiffness of the polymer brushes caused by their mutual interaction

Epigenetic mechanisms in virus-induced tumorigenesis

About 15–20% of human cancers worldwide have viral etiology. Emerging data clearly indicate that several human DNA and RNA viruses, such as human papillomavirus, Epstein–Barr virus, Kaposi’s sarcoma-associated herpesvirus, hepatitis B virus, hepatitis C virus, and human T-cell lymphotropic virus, contribute to cancer development. Human tumor-associated viruses have evolved multiple molecular mechanisms to disrupt specific cellular pathways to facilitate aberrant replication. Although oncogenic viruses belong to different families, their strategies in human cancer development show many similarities and involve viral-encoded oncoproteins targeting the key cellular proteins that regulate cell growth. Recent studies show that virus and host interactions also occur at the epigenetic level. In this review, we summarize the published information related to the interactions between viral proteins and epigenetic machinery which lead to alterations in the epigenetic landscape of the cell contributing to carcinogenesis

Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.

Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field

Comparing of Young’s modulus of shamotte refractories determined by static and dynamic methods

W ramach pracy wyznaczono i porównano wartości modułu sprężystości podłużnej wyrobu szamotowego, wyznaczonego trzema metodami: statyczną przy ściskaniu oraz dwoma dynamicznymi – rezonansową i ultradźwiękową. Najniższe wartości mierzonych modułów uzyskano metodą statyczną, najwyższe dynamiczną – ultradźwiękową. Wyniki uzyskane metodą rezonansową były o kilka do kilkunastu procent wyższe od tych otrzymanych metodą statyczną, a metodą ultradźwiękową były wyższe o 30%. Omówiono różnice w uzyskanych wynikach, wskazując ich przyczyny. Dyskusję na ten temat oparto na rozważaniach teoretycznych i doniesieniach literaturowych.The paper presents the modulus of elasticity of shamotte refractories determined by three different methods: static during compression and two dynamic resonance and ultrasonic. The lowest values of modulus were obtained by the static method, the highest ones by the dynamic ultrasonic method. The results obtained by the resonance method were a few to several percent higher than those obtained by the static method. The results obtained by the ultrasonic method have values ca. thirty percent higher then those obtained by the static method. The differences in the obtained results were discussed and the reasons of these differences were indicated. Discussion about the differences in the results obtained by static and dynamic methods was based on theoretical considerations and literature reports

Comparative tests of thermal shock resistance of magnesite material

Odporność na wstrząsy cieplne decyduje o wyborze materiału w przypadku jego użytkowania w warunkach, w których występuje gradient temperatury. Obejmuje to wyroby stosowane w procesach wysokotemperaturowych, prowadzonych zarówno w sposób okresowy, jak i ciągły. Odporność na wstrząsy cieplne określana jest w sposób empiryczny poprzez umowną ocenę skutków wywołanych przez bezpośrednie poddawanie wyrobów cyklicznym zmianom temperatury. W celu oznaczania odporności na wstrząsy cieplne zostało opracowanych wiele metod pomiarowych, umożliwiających szacowanie efektywnego czasu pracy wyrobu w warunkach zmiennej temperatury. Metoda pomiarowa jest tym doskonalsza, im warunki badania bardziej odwzorowują autentyczne warunki pracy badanego materiału. Wymóg ten jest jednak bardzo trudny, a wręcz niemożliwy do spełnienia w warunkach laboratoryjnych. W niniejszej pracy dokonano przeglądu metod oznaczania odporności na wstrząsy cieplne materiałów ogniotrwałych. Wzięto pod uwagę zarówno metody znormalizowane, jak i nieznormalizowane opisane w dostępnej literaturze. Opisane metody porównano i wskazano najistotniejsze różnice w metodyce oraz sposobie prezentacji wyniku badania oraz omówiono słabe strony tych metod. Zaprezentowano wyniki porównawczych badań odporności na wstrząsy cieplne materiału magnezytowego uzyskane w dwóch niezależnych laboratoriach. Badania zostały przeprowadzone według wcześniej określonej metodyki i miały na celu ustalenie wpływu warunków przeprowadzenia badania na wynik końcowy.Thermal shock resistance determines the choice of material for applications in temperature gradient conditions. This includes products used in batch and continuous high temperature processes. Thermal shock resistance is determined empirically by evaluation of the effects of direct sample treatment by cyclic changes of temperature. There have been developed many methods of thermal shock resistance determination. This methods allow to determine the effective time of the product live under conditions of variable temperature. The measuring method is the more accurate when the more test conditions are closer to real working conditions of the testes material. This requirement is very difficult or even impossible to meet in the laboratory. This paper presents the review of the methods for the thermal shock resistance testing of refractory materials. Both the standardised and not standardised methods described in the literature are presented. These methods were compared and identified the most important differences in methodology and presentation of the test results. The weaknesses of the presented methods were discussed. The results of comparative tests of thermal shock resistance of magnesite material obtained in two independent laboratories were presented. Tests were carried out according to predetermined methodology. The tests aimed to determine the influence of test conditions on the result