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51.
The article presents research on ergonomics, biophysical comfort and safety of protective clothing. The resistance of the structural, thermal and mechanical properties of five fabrics (CBXS400, GG200T, Twaron CT736, Dyneema HB26 and T1790C), differing in geometry and raw material composition used in space suits, to dangerous ionizing radiation (β and γ) occurring in space was tested. For both types of radiation, four identical one-time doses in the range of 25–100 kGy were used. The effect of the applied absorbed doses of β and γ radiation on the parameters of textiles influencing ergonomics and safety of the cosmonaut’s work was verified by structural tests (micro-computed tomography and optical microcopy), thermal resistance tests (sweating guarded-hotplate) and strength tests (tensile testing machine). Experimental studies of thermal properties are supplemented with heat transport simulations using the finite volume method performed with 3D models of real textiles. The greatest reduction of thermal resistance for Twaron CT736 (−0.0667 m2·°C·W−1 for 100 kGy of β-radiation) and Dyneema HB26 (−0.0347 m2·°C·W−1 for 50 kGy of β-radiation) is observed. Strength tests have shown that all tested textiles are resistant to both types of radiation. Three textiles were selected to create a three-layer assembly with potential application in a cosmonaut’s glove (Extravehicular Activity—EVA). 相似文献
52.
IntroductionRetroperitoneal fibrosis (RPF) is a rare disease associated with the formation of hard inflammatory and fibrous tissue in the retroperitoneum. Taking into consideration the fact that RPF is a rare disease with different subtypes, we compared the basal clinical and biochemical characteristics of the vascular and urorenal subtypes.Patients and methodsFrom January 2005 until December 2021, 27 patients were identified as vascular subtype (18 males) and 11 as urorenal subtype (9 males).ResultsPatients with a primary urorenal origin had significantly worse kidney function as reflected by serum creatinine and eGFR (both p < 0.001); they also had higher serum cholesterol (p < 0.01). Hypertension, diabetes, hyperlipidemia and nicotinism were significantly more prevalent in vascular subtype (all p < 0.001).ConclusionVascular subtype is more prevalent in our study with more cardiovascular risk factor present. Due to the diversity of symptoms, diagnosis of RPF becomes a challenge for specialists as well as therapy. 相似文献
53.
Katarzyna Kobiela-Mendrek Marcin Bczek Jan Broda Monika Rom Ingvild Espelien Ingun Klepp 《Materials》2022,15(9)
Wool of mountain sheep, treated nowadays as a waste or troublesome byproduct of sheep husbandry, was used for the production of sound-absorbing materials. Felts of two different thicknesses were produced from loose fibres. Additionally, two types of yarn, ring spun and core rug, were obtained. The yarns were used for the production of tufted fabric with cut and loop piles. During the examinations, basic parameters of the obtained materials were determined. Then, according to standard procedure with the use of impedance tube, the sound absorption coefficient was measured, and the noise reduction coefficient (NRC) was calculated. It was revealed that felt produced from coarse wool exhibits high porosity, and its sound absorbing capacity is strongly related to the felt thickness. For thicker felt the NRC achieved 0.4, which is comparable with the NRC of commercial ceiling tiles. It was shown that the crucial parameter influencing the sound absorption of the tufted fabrics was the pile height. For both types of yarns, when the height of the pile was increased from 12 to 16 mm, the NRC increased from 0.4 to 0.42. The manufactured materials made from local wool possess good absorption capacity, similar to commercial products usually made from more expensive wool types. The materials look nice and can be used for noise reduction as inner acoustic screens, panels, or carpets. 相似文献
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Autoimmune pancreatitis is a rare form of pancreatitis characterized by responsiveness to steroid therapy and an often relapsing disease course. The mainstay of therapy is oral corticotherapy. Associations of interstitial nephritis with various autoimmune disorders have been described. We hereby report the case of a 69-year-old Caucasian man with a 2-year history of autoimmune pancreatitis, who presented with impairment of kidney function, proteinuria, and hypertension. Renal histopathology showed severe diffuse interstitial nephritis. With oral prednisone and ACE inhibitor therapy, complete recovery of kidney function was not achieved and proteinuria persisted. Therefore, mycophenolate mofetil was initiated. After 8 weeks, serum creatinine decreased, and a nearly complete and sustained resolution of proteinuria was seen, while tapering oral steroid doses. With autoreactive T cells playing a major role in the pathogenesis of both diseases, a common etiology of pancreatitis and interstitial nephritis can be assumed, and the beneficial effects of an inhibitor of lymphocyte proliferation, such as mycophenolate mofetil, can be explained. We infer from our case that mycophenolate mofetil can be effective in the control of simultaneous autoimmune pancreatitis and interstitial nephritis. 相似文献
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Monika D. Kraszewska Małgorzata Dawidowska Maria Kosmalska Łukasz Sędek Władysław Grzeszczak Jerzy R. Kowalczyk Tomasz Szczepański Michał Witt 《Blood cells, molecules & diseases》2013,50(1):33-38
T‐cell acute lymphoblastic leukemia is a heterogeneous malignancy originating from developing lymphocyte precursors likely due to mutations in genes regulating thymocyte differentiation. Here, we characterized mutation status of BCL11B and FLT3 genes, presumably involved in T-ALL, together with FBXW7 and NOTCH1 as known players in T-ALL in 65 pediatric T-cell acute lymphoblastic leukemia patients. We also aimed at the assessment of prognostic value of NOTCH1 and FBXW7 mutations in ALL-IC BFM 2002 protocol.FLT3 and BCL11B mutations were detected in 3% and 2% of patients, respectively. FBXW7 mutations were observed in 8% of patients, while NOTCH1 was mutated in 40%. No correlation was found between NOTCH1 and FBXW7 mutations and traditionally used clinical factors or molecular features. In total we have detected nine mutations, which have not been previously described by others. Eight of them were found in NOTCH1 and one in BCL11B gene.Observed frequencies of NOTCH1 and FBXW7 are in line with previous reports, thus confirming postulated participation of these two genes in T-ALL pathomechanism. Moreover, we report on mutation frequency of FLT3 and BCL11B, not extensively studied in T-ALL so far. Finally, we suggest a putative role of BLC11B as an oncogene in T-ALL pathogenesis. 相似文献
58.
Monika Koziel Dan Corcoran Isabelle O'Callaghan Roy D. Sleator Brigid Lucey 《Diagnostic microbiology and infectious disease》2013
A total of 717 faeces samples were tested prospectively using the EntericBio Panel II® detection system (Serosep, Limerick, Ireland), in parallel with routine laboratory testing, which combines the EntericBio® system with retrospective culture of each specimen where a target is detected. Discrepancy analysis was conducted using molecular methods. The EntericBio Panel II® assay produced 585 negative and 132 positive results, namely, Campylobacter spp. (n = 66); SLT 1 and/or SLT 2 (n = 64); Salmonella spp. (n = 5); and Shigella spp. (n = 0). Three samples were positive for more than 1 target. Of these results, 4 Campylobacter spp. detections and 4 SLT 1/ SLT 2 detections remained unconfirmed, and the system failed to detect 2 Campylobacter spp. targets detected by routine laboratory detection. The sensitivity, specificity, positive predictive value, negative predictive value, and efficiency were calculated to be 98.4%, 98.7%, 93.9%, 99.7%, and 98.6%, respectively. 相似文献
59.
Bijak M Mayr W Rakos M Hofer C Lanmüller H Rafolt D Reichel M Sauermann S Schmutterer C Unger E Russold M Kern H 《Artificial organs》2002,26(3):224-227
An eight-channel stimulation system, currently intended for stimulation of lower extremities, was developed and is introduced. The major development goals were easy handling, modularity to make the system easily adaptable for other functional electrical stimulation (FES) applications, and a wide stimulation parameter range for application-specific parameter optimization. For paraplegic stepping, the system worn by the patient consists of 2 four-channel stimulation modules, a central unit holding the battery and circuitry for power management and communication control, a wireless remote control unit, and a palmtop computer as the main control and input device. A software package for Microsoft Windows supports the design and optimization of stimulation sequences in the rehabilitation center. First tests with patients familiar with FES showed smoother movements during stepping and acceptable good handling. In combination with the PC software, the required stimulation sequences could be created in a very short time. 相似文献
60.