9 research outputs found
Koncepcja uk艂adu odzyskiwania energii z ruroci膮gu szybowego.
Przedmiotem artyku艂u jest koncepcja uk艂adu odzyskiwania energii ze strugi wody technologicznej transportowanej do wyrobisk ruroci膮giem przeciwpo偶arowym w szybie. Przedstawiono problem projektowania mini turbiny oraz dob贸r pozosta艂ych urz膮dze艅 uk艂adu. Oszacowano ilo艣膰 rocznie produkowanej energii elektrycznej oraz okres zwrotu nak艂ad贸w inwestycyjnych
Characterization and quality control of 2.5 MV beam in TrueBeam medical linear accelerator
Praca skupia si臋 na charakterystyce oraz procesie kontroli jako艣ci nowej, megawoltowej energii promieniowana, kt贸ra zosta艂a zaimplementowana w medycznym akceleratorze liniowym Varian TruBeam. U偶ycie wi膮zki promieniowania o efektywnym potencjale przyspieszaj膮cym 2,5 MV redukuje dawk臋 promieniowania, jak膮 otrzymuje pacjent w trakcie obrazowania o oko艂o 50% oraz zapewnia znacznie lepsz膮 jako艣膰 obrazu. W celu kontroli jako艣ci nowej energii promieniowania dokonano pe艂nej charakterystyki wi膮zki poprzez wyznaczanie procentowej dawki g艂臋boko艣ciowej, pomiar profili i kalibracj臋 mocy dawki, wykonano test Winstona-Lutza, a tak偶e oceniono jako艣膰 obrazowania z u偶yciem fantomu Leeds TOR 18FG. Wyznaczone parametry umo偶liwi艂y opracowanie protok贸艂 QA, kt贸re stosowane s膮 w praktyce klinicznej.This work describes the characteristics and quality control process of the new megavoltage energy, which was implemented on the Varian TruBeam medical linear accelerator. New beam, generated by 2,5 MV nominal accelerating potential reduces the dose of radiation received by the patient during imaging process by 50% and provides better image quality. In order to control the quality of 2,5 MV beam, full beam characteristic was performed by measure a percent depth dose, beam profiles and outputs calibration, the Winston-Lutz test was performed. The image quality was evaluated using the Leeds TOR 18FG phantom was evaluated. The determined parameters allowed to develop QA protocol, which are used in clinical routine
Quality Assurance in Nuclear Medicine. Routine tests of quality control of PET and PET/CT systems
Jednym z warunk贸w zapewnienia i utrzymania wysokiego poziomu jako艣ci bada艅 diagnostycznych w medycynie nuklearnej jest wykonywanie test贸w kontroli jako艣ci zgodnie z zaleceniami i regulacjami prawnymi. Testy podstawowe kontroli jako艣ci, b臋d膮ce jednym z element贸w systemu kontroli jako艣ci w zak艂adach medycyny nuklearnej, s膮 nieodzown膮 cz臋艣ci膮 rutynowej pracy klinicznej. Niniejsza praca ma na celu przedstawienie procedur wykonywania test贸w podstawowych kontroli jako艣ci dla skaner贸w PET i PET/CT.One of the conditions for ensuring and maintaining a high level of quality diagnostic exams in nuclear medicine is to perform quality control tests in accordance with legal recommendations and regulations. Basic quality control tests, which are one of the elements of the quality control system in nuclear medicine departments, are a very important part of routine clinical work. This work aims to present the procedures for performing basic quality control tests for PET and PET/CT scanners
Comparison of three different phantoms used for Winston-Lutz test with Artiscan software
BackgroundOne of the most important test in every quality assurances process of medical linear accelerators is the Winston-Lutz test, allowing an evaluation of the treatment isocentre in the light of uncertainty of the position of the collimator, the gantry and the couch.AimThe purpose of this work was analysis of the results of the Winston-Lutz test performed with three different phantoms for two different accelerators.Materials and methodsMeasurements were performed on two Varian machines: TrueBeam equipped with aS1200 EPID and TrueBeam equipped with aS1000 EPID. During the study three different phantoms dedicated for verification of the radiation isocentre were used: PTW Isoball, AQUILAB Isocentre Phantom and Varian Isocentre Cube. Analysis of the DICOM images was performed in Artiscan software.ResultsFor TrueBeam with as1200 EPID, gantry MV isocentre was about 0.18鈥痬m larger for Varian Isocentre Cube than for two other phantoms used in this study. The largest variability of this parameter was observed for the couch. The results differed to 1.16鈥痬m. For TrueBeam with as1000 EPID, results for collimator isocentre with PTW Isoball phantom were about 0.10鈥痬m larger than for two other phantoms. For the gantry, results obtained with Varian Isocentre Cube were 0.21鈥痬m larger.ConclusionThe obtained results for all three phantoms are within the accepted tolerance range. The largest differences were observed for treatment couch, which may be related to the phantom mobility during couch movement
Smart Polymeric Nanocarriers of Met-enkephalin
This study describes a novel approach
to polymeric nanocarriers
of the therapeutic peptide met-enkephalin based on the aggregation
of thermoresponsive polymers. Thermoresponsive bioconjugate poly颅((di颅(ethylene
glycol) monomethyl ether methacrylate)-<i>ran</i>-(oligo颅(ethylene
glycol) monomethyl ether methacrylate) is synthesized by AGET ATRP
using modified met-enkephalin as a macroinitiator. The abrupt heating
of bioconjugate water solution leads to the self-assembly of bioconjugate
chains and the formation of mesoglobules of controlled sizes. Mesoglobules
formed by bioconjugates are stabilized by coating with cross-linked
two-layer shell via nucleated radical polymerization of <i>N</i>-isopropylacrylamide using a degradable cross-linker. The targeting
peptide RGD, containing the fluorescence marker carboxyfluorescein,
is linked to a nanocarrier during the formation of the outer shell
layer. In the presence of glutathione, the whole shell is completely
degradable and the met-enkephalin conjugate is released. It is anticipated
that precisely engineered nanoparticles protecting their cargo will
emerge as the next-generation platform for cancer therapy and many
other biomedical applications
Poly[tri(ethylene glycol) ethyl ether methacrylate]-Coated Surfaces for Controlled Fibroblasts Culturing
Well-defined
thermosensitive poly颅[tri颅(ethylene glycol) monoethyl ether methacrylate]
(P颅(TEGMA-EE)) brushes were synthesized on a solid substrate by the
surface-initiated atom transfer radical polymerization of TEGMA-EE.
The polymerization reaction was initiated by 2-bromo-2-methylpropionate
groups immobilized on the surface of the wafers. The changes in the
surface composition, morphology, philicity, and thickness that occurred
at each step of wafer functionalization confirmed that all surface
modification procedures were successful. Both the successful modification
of the surface and bonding of the P颅(TEGMA-EE) layer were confirmed
by X-ray photoelectron spectroscopy (XPS) measurements. The thickness
of the obtained P颅(TEGMA-EE) layers increased with increasing polymerization
time. The increase of environmental temperature above the cloud point
temperature of P颅(TEGMA-EE) caused the changes of surface philicity.
A simultaneous decrease in the polymer layer thickness confirmed the
thermosensitive properties of these P颅(TEGMA-EE) layers. The thermosensitive
polymer surfaces obtained were evaluated for the growth and harvesting
of human fibroblasts (basic skin cells). At 37 掳C, seeded cells
adhered to and spread well onto the P颅(TEGMA-EE)-coated surfaces. A
confluent cell sheet was formed within 24 h of cell culture. Lowering
the temperature to an optimal value of 17.5 掳C (below the cloud
point temperature of the polymer, <i>T</i><sub>CP</sub>,
in cell culture medium) led to the separation of the fibroblast sheet
from the polymer layer. These promising results indicate that the
surfaces produced may successfully be used as substrate for engineering
of skin tissue, especially for delivering cell sheets in the treatment
of burns and slow-healing wounds
Metabolic syndrome is associated with similar long-term prognosis in non-obese and obese patients. An analysis of 45 615 patients from the nationwide LIPIDOGRAM 2004-2015 cohort studies
Aims We aimed to evaluate the association between metabolic syndrome (MetS) and long-term all-cause mortality. Methods The LIPIDOGRAM studies were carried out in the primary care in Poland in 2004, 2006 and 2015. MetS was diagnosed based on the National Cholesterol Education Program, Adult Treatment Panel III (NCEP/ATP III) and Joint Interim Statement (JIS) criteria. The cohort was divided into four groups: non-obese patients without MetS, obese patients without MetS, non-obese patients with MetS and obese patients with MetS. Differences in all-cause mortality was analyzed using Kaplan-Meier and Cox regression analyses. Results 45,615 participants were enrolled (mean age 56.3, standard deviation: 11.8 years; 61.7% female). MetS was diagnosed in 14,202 (31%) by NCEP/ATP III criteria, and 17,216 (37.7%) by JIS criteria. Follow-up was available for 44,620 (97.8%, median duration 15.3 years) patients. MetS was associated with increased mortality risk among the obese (hazard ratio, HR: 1.88 [95% CI, 1.79-1.99] and HR: 1.93 [95% CI 1.82-2.04], according to NCEP/ATP III and JIS criteria, respectively) and non-obese individuals (HR: 2.11 [95% CI 1.85-2.40] and 1.7 [95% CI, 1.56-1.85] according to NCEP/ATP III and JIS criteria respectively). Obese patients without MetS had a higher mortality risk than non-obese patients without MetS (HR: 1.16 [95% CI 1.10-1.23] and HR: 1.22 [95%CI 1.15-1.30], respectively in subgroups with NCEP/ATP III and JIS criteria applied). Conclusions MetS is associated with increased all-cause mortality risk in non-obese and obese patients. In patients without MetS obesity remains significantly associated with mortality. The concept of metabolically healthy obesity should be revised