Distribution of snow accumulation on some glaciers of Spitsbergen

We describe the spatial variability of snow accumulation on three selected gla− ciers in Spitsbergen (Hansbreen, Werenskioldbreen and Aavatsmarkbreen) in the winter seasons of 1988/89, 1998/99 and 2001/2002 respectively. The distribution of snow cover is determined by the interrelationships between the direction of the glacier axes and the domi− nant easterly winds. The snow distribution is regular on the glaciers located E−W, but is more complicated on the glaciers located meridionally. The western part of glaciers is more predisposed to the snow accumulation than the eastern. This is due to snowdrift intensity. Statistical relationships between snow accumulation, deviation of accumulation from the mean values and accumulation variability related to topographic parameters such as: alti− tude, slope inclination, aspect, slope curvature and distance from the edge of the glacier have been determined. The only significant relations occured between snow accumulation and altitude (r = 0.64–0.91)

Redukcja ekspozycji na promieniowanie podczas ablacji migotania przedsionków z wykorzystaniem systemu elektroanatomicznego 3D zintegrowanego z fluoroskopią w codziennej praktyce klinicznej

Introduction. Fluoroscopy integration with three dimensional (3D) electroanatomical mapping system may allow dose reduction while invasive electrophysiological procedures. In this retrospective study we present real-population experience with integrated model. Material and methods. Ninety-six patients with paroxysmal atrial fibrillation (AF) after radiofrequency pulmonary vein isolation have been analyzed. In 48 patients, 3D mapping system integrated with fluoroscopy (Carto 3 UniVu) has been used. Clinical and peri-procedural data, inclusive, fluoroscopy time and dose, in-hospital complications and efficacy rate at 6 months have been compared. Results. Patients treated with classic 3D mapping system were significantly older (p = 0.036). Both fluoroscopy mean time (11.6 ± 4.3 vs. 6.7 ± 2.9 minutes, p < 0.05) and a median of the fluoroscopy dose [460.0 (IQR: 288.0–785.5) vs. 271.0 (IQR 145.0–535.0) mGy, p < 0.05] have been significantly reduced by using Carto3 UniVu. Total procedure time was comparable between groups. Periprocedural complications and recurrence of clinical arrhythmia rate in 6-month follow-up were comparable. Conclusions. Utilization of novel 3D mapping systems with classic fluoroscopy integration supports the radiation time and the dose reduction during AF ablation procedure, without any adverse impact on the total procedure time, complication or success rate. This real-life population results corresponds with previously presented prospective studies.Wstęp. Integracja obrazu fluoroskopowego z systemem obrazowania elektroanatomicznego 3D może zmniejszać ekspozycję na promieniowanie jonizujące podczas zabiegów elektrofizjologicznych. W tym retrospektywnym badaniu zaprezentowano wyniki stosowania zintegrowanego systemu elektroanatomicznego u pacjentów poddawanych ablacji migotania przedsionków w codziennej praktyce. Materiał i metody. Przeanalizowano 96 pacjentów z napadowym migotaniem przedsionków poddanych zabiegowi izolacji żył płucnych prądem o częstotliwości radiowej. U 48 z nich wykorzystano system elektroanatomiczny 3D zintegrowany z fluoroskopią (Carto 3 UniVu). U pozostałych zastosowano klasyczny system elektroanatomiczny 3D (Carto 3). Analizie poddano dane kliniczne, a także okołozabiegowe, w szczególności dawkę i czas skopii, a także częstość powikłań i nawrotu arytmii w okresie 6 miesięcy. Wyniki. Pacjenci leczeni z użyciem klasycznego systemu 3D byli istotnie starsi (p = 0,036). We wszystkich przypadkach uzyskano całkowitą izolację żył płucnych. Zarówno średni czas skopii (11,6 ± 4,3 vs. 6,7 ± 2,9 min; p &lt; 0,05), jak i mediana dawki (460,0 [IQR 288,0–785,5] vs. 271,0 [IQR 145,0–535,0] mGy; p &lt; 0,05) były istotnie mniejsze u pacjentów w grupie, w której stosowano Carto 3 UniVu. Całkowity czas zabiegu w obu grupach był porównywalny. Częstości powikłań okołozabiegowych oraz nawrotu klinicznej arytmii były porównywalne w obu grupach. Wnioski. Wykorzystanie nowego systemu elektroanatomicznego 3D zintegrowanego z klasyczną fluoroskopią pozwala na zmniejszenie ekspozycji na promieniowanie jonizujące podczas zabiegów ablacji migotania przedsionków, nie wpływając jednocześnie negatywnie na czasu zabiegu, ryzyko komplikacji czy skuteczność. Dane te, uzyskane w toku codziennej praktyki, korespondują z wcześniejszymi dowodami uzyskanymi z badań klinicznych

Interpreting myocardial perfusion scintigraphy using single-photon emission computed tomography. Part 1

This article discusses the protocol for myocardial perfusion scintigraphy performed with single-photon emission computed tomography (SPECT). Indications for SPECT are listed with consideration given to the results of the increasingly more common angio-CT examinations of the coronary arteries (multislice computed tomography). The paper also presents basic information about interpreting the results, including the scores of left ventricle myocardial perfusion using the 17-segment polar map, and explains the concept of total perfusion deficit

Wide-field magnetometry using nitrogen-vacancy color centers with randomly oriented micro-diamonds

Magnetometry with nitrogen-vacancy (NV) color centers in diamond has gained significant interest among researchers in recent years. Absolute knowledge of the three-dimensional orientation of the magnetic field is necessary for many applications. Conventional magnetometry measurements are usually performed with NV ensembles in a bulk diamond with a thin NV layer or a scanning probe in the form of a diamond tip, which requires a smooth sample surface and proximity of the probing device, often limiting the sensing capabilities. Our approach is to use micro- and nano-diamonds for wide-field detection and mapping of the magnetic field. In this study, we show that NV color centers in randomly oriented submicrometer-sized diamond powder deposited in a thin layer on a planar surface can be used to detect the magnetic field. Our work can be extended to irregular surfaces, which shows a promising path for nanodiamond-based photonic sensors

Optical magnetometry based on nanodiamonds with nitrogen-vacancy color centers

Nitrogen-vacancy color centers in diamond are a very promising medium for many sensing applications such as magnetometry and thermometry. In this work, we study nanodiamonds deposited from a suspension onto glass substrates. Fluorescence and optically detected magnetic resonance spectra recorded with the dried-out nanodiamond ensembles are presented and a suitable scheme for tracking the magnetic-field value using a continuous poly-crystalline spectrum is introduced. Lastly, we demonstrate a remote-sensing capability of the high-numerical-aperture imaging fiber bundle with nanodiamonds deposited on its end facet

Integration of fluorescent, NV-rich nanodiamond particles with AFM cantilevers by focused ion beam for hybrid optical and micromechanical devices

In this paper, a novel fabrication technology of atomic force microscopy (AFM) probes integrating cantilever tips with an NV-rich diamond particle is presented. Nanomanipulation techniques combined with the focused electron beam-induced deposition (FEBID) procedure were applied to position the NV-rich diamond particle on an AFM cantilever tip. Ultrasonic treatment of nanodiamond suspension was applied to reduce the size of diamond particles for proper geometry and symmetry. The fabricated AFM probes were tested utilizing measurements of the electrical resistance at highly oriented pyrolytic graphite (HOPG) and compared with a standard AFM cantilever performance. The results showed novel perspectives arising from combining the functionalities of a scanning AFM with optically detected magnetic resonance (ODMR). In particular, it offers enhanced magnetometric sensitivity and the nanometric resolution

Przezczaszkowa ultrasonografia dopplerowska (TCD) u chorych z poszerzonym układem komorowym : poszukiwanie dodatkowych wskaźników kwalifikacji do zabiegu implantacji układu zastawkowego

Background: Ventriculomegaly without increased intracranial pressure is observed both in normal-pressure hydrocephalus (NPH) and idiopathic cerebral atrophy (CA). Investigating additional parameters to differentiate these diseases is important for a good qualification of shunt implantation. The study presents the influence of intravenous administration of acetazolamide on cerebral blood flow velocity (BFV) and cerebrovascular reactivity (CVR) in 23 patients with ventriculomegaly and symptoms of cognitive function disorders. The aim was to establish the differences in the dynamic cerebral hemodynamics parameters in NPH and CA patients. Material/Methods: Measurement of BFV was performed in 23 patients using transcranial Doppler (TCD) ultrasonography before and 20 minutes after intravenous administration of 1000 mg acetazolamide. CVR was calculated as the percent change from the baseline mean BFV value and assessed bilaterally in the middle (MCA), anterior (ACA), posterior (PCA), and internal carotid cerebral (ICA) arteries in the intracranial part. Additionally, BFV was evaluated in selected patients during a lumbar infusion test. The patients were divided into 2 groups: those with NPH and those with CA. Results: BFV values were decreased both in the NPH and the CA group compared with the control group (healthy volunteers of the same age). There were no significant differences between the two groups. In the CA group a complete lack of CVR was observed in all examined arteries. In the NPH group, CVR was maintained, while mean BFV (MFV) changed 37±4% in the MCA, 26±6% in the ACA, 33±5% in the PCA, and 30±4% in the ICA. There were statistically significant differences in CVR values between the groups. A decrease in initial BFV in all examined intracranial arteries and a complete lack of CVR is characteristic of the CA group. Conclusions: Maintenance of CVR and a simultaneous decrease in BFV is a characteristic of the NPH group, but among the patients in that group we found differences in cerebrovascular response to acetozolamide, In both groups there were no significant differences in BFV in the MCA during the lumbar infusion test. The acetazolamide test appears as an additional factor in the differential diagnosis of NPH and CA

QUALITY OF GROUNDWATER AND AQUATIC HUMIC SUBSTANCES FROM MAIN RESERVOIRE OF GROUND WATER No. 333

The conducted research included the estimation of the quality of groundwater from the Main Reservoir of Ground Water No. 333 area in Opole District, Poland. The groundwater in the analyzed region shows high diversity in quality. The main threat for the quality of water in this region is the human household activity. The main pollutants of groundwater are: dissolved phosphorus, nitrate and ammonium. The quality and quantity of dissolved humic substances in groundwater were also investigated. The results showed that the contents of water-extractable organic carbon varied. Presently, the analyzed groundwater is characterized by large differences in dissolved forms of organic carbon. During migration of the soil solution through the soil profile to groundwater, dissolved humic substances undergo qualitative and quantitative changes. Correlation analysis between the quantity of carbon in soil and aquatic humic substances, especially fulvic acids, indicates the possibility of their translocation in soil profiles and their transformation and migration to groundwater. This conclusion can be confirmed by FT-IR-analysis