Grid-enhanced X-ray coded aperture microscopy with polycapillary optics

Polycapillary devices focus X-rays by means of multiple reflections of X-rays in arrays of bent glass capillaries. The size of the focal spot (typically 10–100 $\mu$ m) limits the resolution of scanning, absorption and phase-contrast X-ray imaging using these devices. At the expense of a moderate resolution, polycapillary elements provide high intensity and are frequently used for X-ray micro-imaging with both synchrotrons and X-ray tubes. Recent studies have shown that the internal microstructure of such an optics can be used as a coded aperture that encodes high-resolution information about objects located inside the focal spot. However, further improvements to this variant of X-ray microscopy will require the challenging fabrication of tailored devices with a well-defined capillary microstructure. Here, we show that submicron coded aperture microscopy can be realized using a periodic grid that is placed at the output surface of a polycapillary optics. Grid-enhanced X-ray coded aperture microscopy with polycapillary optics does not rely on the specific microstructure of the optics but rather takes advantage only of its focusing properties. Hence, submicron X-ray imaging can be realized with standard polycapillary devices and existing set-ups for micro X-ray fluorescence spectroscopy

SARS-CoV-2 neurotropism and other possible causes of olfactory disorders in COVID-19

Coronavirus disease 2019 (COVID-19) is an acute infectious respiratory disease (AIRD) caused by infection with the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first cases were diagnosed and reported in Wuhan, central China, in November 2019. The disease initially occurred locally. However, the number of infected individuals increased dynamically and spread worldwide. The most common symptoms of the SARS-CoV-2 infection include malaise, fever, dry cough and dyspnoea. Over time, reports of new COVID-19 symptoms included taste and smell disorders. A potential cause of these disorders is related to neurotropism, i.e. the affinity of SARS-CoV-2 to the nervous system. Angiotensin-converting enzyme 2 receptor is essential in the pathogenesis of SARS-CoV-2 infection. The receptor is found in many tissues and organs, including the olfactory epithelium, neurons and neuroglial cells. Another potential cause is neuroinvasiveness, i.e. the ability of the virus to invade the central nervous system, and thereby damage its structures. As a result, olfactory disorders may occur. Other concepts, such as the inflammatory response of the body and the concept of stroke or damage to olfactory supporting cells, are also considered

Identification and determination of ergot alkaloids in Morning Glory cultivars

Seeds of plants from Ipomoea genera contain numerous ergot alkaloids, including psychoactive ergine and ergometrine, and are often abused as so-called “legal highs.” In this work, an analytical method for determination of ergine and ergometrine, and identification of other alkaloids was developed, optimized, and validated. Three extraction techniques, ultrasound-assisted extraction in bath, or with sonotrode, and microwave-assisted extraction were evaluated, and it was concluded that ultrasonic bath is the most suitable technique for extraction of ergot alkaloids. The extraction method was later optimized using a Doehlert experimental design with response surface methodology and used together with the optimized LC-Q-TOF-MS method. The analytical procedure was validated in terms of recovery and matrix effect, repeatability, and intermediate precision. Limits of detection and quantification were 1.0 and 3.0 ng mL(–1), respectively, and were sufficient for determination of ergot alkaloids in Ipomoea seeds. The analysis revealed that from five kinds of seeds purchased from different vendors, only three contained ergot alkaloids. Concentration of alkaloids and their relative abundance was similar in samples representative for whole seeds packs; however, when single seeds were analyzed, significant discrepancies in ergine and ergometrine concentrations were detected. [Figure: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00216-016-9322-5) contains supplementary material, which is available to authorized users

WYDZIAŁ ELEKTRYCZNY POLITECHNIKI ŚLĄSKIEJ – 70 LAT TRADYCJI

The article presents the Faculty of Electrical Engineering of Silesian University of Technology, which celebrated its 70th anniversary last year. The past 70 years are a good opportunity to summarize the changes that have taken place at the Faculty in the scientific, research and didactic fields and to outline plans for the future. The history, the organizational structure of the Faculty and the cooperation with industry are also described in the article.W roku ubiegłym Wydział Elektryczny Politechniki Śląskiej świętował siedemdziesięciolecie swojego istnienia. Jubileusz ten stał się okazją do dokonania podsumowania jego dotychczasowej działalności i nakreślenia planów na najbliższą przyszłość. W artykule zaprezentowano historię i strukturę organizacyjną Wydziału, a także jego działalność dydaktyczną i badawczą oraz współprace z partnerami przemysłowymi

First white beam on a von Hámos spectrometer at the PolyX beamline of SOLARIS

Synchrotrons are brilliant sources of X-ray radiation used in a variety of methods to study the structure of matter and dynamics of processes on the atomic scale. X-ray spectroscopy methods at synchrotrons are typically combined with the beam monochromatization which guarantees better energy resolution but also reduces orders of magnitude the photon flux incident on the sample and thus wastes the vast majority of the photons produced. Here we report on the commissioning of an X-ray spectrometer at the PolyX beamline of SOLARIS specialized in application of white, broadband and monochromatic X-ray beam in multimodal microimaging, microtomography and microscpectroscopic studies. The spectrometer was used to acquire good quality Fe K-edge X-ray absorption spectrum over about 120 eV-range within seconds. In this work we present the first X-ray absorption spectrum measured using a synchrotron white beam in combination with a von Hámos geometry-based spectrometer

Dynamic equivalents for calculation of power system restoration

The power system must be prepared for the situation that all or a major portion of the system is forced out of service. This can exist as result of a particularly severe faults resulting in the loss of stability and the need for many generators to shut down. In 2003 some European power systems (Italy, parts of London and Scandinavia) but also North America has suffered widespread outages. In the United States over the past 15 years, the large-scale blackouts there have been more frequent than can be explained by random damage. If the blackout occurs, the system as quickly as possible must be restored to normal operations. In the event of a total blackout the power system is divided into different subsystems so that in the event of total grid failure, initially each subsystem is to be restored independently. The initial seconds of the restoration are extremely precious and the required operation made at first moment can help in exactly restoration of the system but any error or small delay during the initial action may cause ending in a sudden, catastrophic change. Between many standards which are used for the preparing of the scenario of system restoration is the requirement that the system operator must, at least once a year simulate system restoration using information on blackstart generation, transmission, nonblackstart generation, load, and the restoration plan The simulation must take into consideration whole spectrums of phenomena which occur from the fault begin till the restoration of power system. The dynamic behavior of connected and cooperated power systems need detailed investigation that will recognize their performance during emergency situation within the whole network. For instance the incorrect operation of protection devices (which are designed to isolate the faulted portion without causing a loss of load to the remaining power system) can cause bad consequences included cascaded disconnection of system components and finally blackout. For this purpose the simulation of electromagnetic and electromechanical transient during faults are required for the prediction and recognition of any incorrect operation of automatic protection systems. During the restoration process depending on scenario practically both the electromechanical and electromagnetic transients will occur. In the worst case, if the system has a complete shut down, the open breakers need to be re-closed to connect the loads and the sequence of breaker operations may affect the voltages and the currents. In such situation also the multiple switching operations are possible and the transients expected from the switching action have to be analyzed. It must be taken into account that a restoration sequence staring from two subsystems will require closing a breaker with different voltage levels on the two sides of the breaker, what will result in significant transients. Till now there is not at disposal the universal power system representation which can be used for the simulation of transients during whole restoration process. The representation of the individual network elements and also the subsystem must correspond to the specific frequency range of the particular transient phenomena. A single physical component may have different model representations depending upon the context of the problems. Power system networks, as shown in The need for the fast but also correct analysis of power systems restoration extorts the reduction of subsystems that are outside the focus of investigation. Replacing subsystems that comprise hundreds or thousands of active components with suitable dynamic equivalents will be essential for power system dynamic analysis. The network equivalent model development originates from the need to have readily available detailed only those component they are of primary interest. This arises not only due to the computational time saving but also from the difficulties of modeling and determining of parameters of a large number of components within the subsystem area. However, it is beyond any doubt that the reduction of the network leads to some inaccuracies of the obtained computed results. Therefore in the previous Wisla, 7-9 czerwca 2004 r. strona 10

Effect of diosmin and diosmetin on the level of pro-inflammatory factors in the endothelium artificially induced with inflammatory stimuli

Introduction: Diosmin and its aglycone diosmetin are phlebotropic drugs used in the treatment of chronic venous insufficiency (CVI). Diosmin increases the elasticity and tension of blood vessel walls, exhibits an antiedematous effect, and acts as an anti-inflammatory agent. As it is commonly known that the endothelium layer plays a significant role in the physiology and pathophysiology of the cardiovascular system, this paper investigates the effect of diosmin and diosmetin on modulating the levels of pro-inflammatory factors in an endothelial cell culture (HUVEC) stimulated by lipopolysaccharide (LPS) or phorbol (PMA). Material and methods: A normal human umbilical vein/vascular endothelium cell line HUV-EC-C (HUVEC) was stimulated with lipopolysaccharide (LPS) or phorbol 12-myristate-13-acetate (PMA). Cell viability was assessed using NR and MTT assays. The levels of human IL-1β, IL-6, IL-10, COX-2, and PGE2 were measured using ELISA kits. Results: Depending on the agent used to initiate inflammation, different levels of factors associated with this state were obtained. Diosmetin significantly decreased the levels of pro-inflammatory IL-1β and IL-6 as well as COX-2 in PMA-treated cells. Meanwhile, diosmin did not affect the interleukins but it lowered COX-2 and increased PGE-2. Upon the LPS stimulation of HUVEC cells, diosmetin increased the levels of PGE2, IL-1β, COX-2, and nitric oxide (NO), while diosmin increased NO and IL-6. Conclusion: Diosmin and diosmetin have different impacts on the levels of pro-inflammatory factors depending on the inflammation inducer. Diosmetin more effectively modulated inflammation than diosmin, suggesting that the attachment of the sugar moiety to the aglycone attenuates its activity

Use of Tc99m-nanocolloid for sentinel nodes identification in cervical cancer

BACKGROUND: The initial draining lymph node for a primary tumor is referred to as the “sentinel” node. Firstly adopted in the management of patients with cutaneous melanoma and breast cancer, it is now widely tested in cervical cancer. In patients with cervical cancer, lymph node status is the most important prognostic factor for survival. In patients with cervical cancer FIGO stage I and II pelvic lymph node metastases are expected in 0–16 and 24.5-31% and para-aortic lymph node metastases are expected in 0–22 and 11–19% of patients. The removal of pelvic and para-aortic lymph nodes is essential for assessing the biology of the disease. Lymphoscintigraphy enables the visualisation of lymphatic drainage patterns from a great variety of tumour sites prior to surgery. Therefore, the current procedure is to perform the pre-operative mapping of sentinel nodes by static and/or dynamic lymphoscintigraphy, followed by in vivo identification using a gamma detection probe and selective surgical resection. MATERIAL AND METHODS: Between 2001–2003, 37 patients with cervical cancer FIGO stage I-IIa were seemed to be qualified to undergo lymphoscintigraphy. The day before surgery 99mTc-nanocolloid (100 MBq; 0.5–1.0 ml in volume) was applied in each quadrant of the cervix or around the tumor. The static scintigraphic scans were performed after 2 hours p.i. using a dual-head large-field-of-view Siemens gamma-camera equipped with high resolution collimators. SNs were identified intra-operatively using a handheld gamma detection probe (Navigator GPS-Tyco) and intra-operative lymphatic mapping with blue dye. After a resection of the SNs, a standard radical hysterectomy with pelvic and low para-aortic lymph node dissection was performed. Tumor characteristics were compared with sentinel node detection and with the histopathological and immunohistochemical results. RESULTS: The scintigraphy showed a focal uptake in 35 of the 37 patients. In all women one or more sentinel lymph nodes were identified intra-operatively. Of them, 24 patients had those located bilaterally. Histologically positive SNs were found in 5 women (13.5%). CONCLUSIONS: A combination pre-operatively administered radioactively labelled albumin with blue dye allows the successful detection of SN in patient with cervical cancer. This technique will result in a real advance in the less aggressive management of patients with early stage cervical cancer. Sentinel lymph node status may be representative of the pelvic lymph nodes status in cervical cancer and thus could provide important information for further treatment