52 research outputs found
Cytomegalovirus infection is a risk factor for tuberculosis disease in infants.
Immune activation is associated with increased risk of tuberculosis (TB) disease in infants. We performed a case-control analysis to identify drivers of immune activation and disease risk. Among 49 infants who developed TB disease over the first 2 years of life, and 129 healthy matched controls, we found the cytomegalovirus-stimulated (CMV-stimulated) IFN-γ response to be associated with CD8+ T cell activation (Spearman's rho, P = 6 × 10-8). A CMV-specific IFN-γ response was also associated with increased risk of developing TB disease (conditional logistic regression; P = 0.043; OR, 2.2; 95% CI, 1.02-4.83) and shorter time to TB diagnosis (Log Rank Mantel-Cox, P = 0.037). CMV+ infants who developed TB disease had lower expression of NK cell-associated gene signatures and a lower frequency of CD3-CD4-CD8- lymphocytes. We identified transcriptional signatures predictive of TB disease risk among CMV ELISpot-positive (area under the receiver operating characteristic [AUROC], 0.98, accuracy, 92.57%) and -negative (AUROC, 0.9; accuracy, 79.3%) infants; the CMV- signature was validated in an independent infant study (AUROC, 0.71; accuracy, 63.9%). A 16-gene signature that previously identified adolescents at risk of developing TB disease did not accurately classify case and control infants in this study. Understanding the microbial drivers of T cell activation, such as CMV, could guide new strategies for prevention of TB disease in infants
Influence of selected parameters of processing with the water-ice jet on the efficiency of the removal of varnish coats
W artykule omówiono obróbkę powłok lakierniczych wysokociśnieniową strugą wodną domieszkowaną cząstkami suchego lodu CO₂. Zaprezentowano wyniki badań nad przydatnością takiej metody do usuwania powłok lakierniczych stosowanych w przemyśle samochodowym.This article covers processing of varnish coats with a high-pressure water jet with CO₂ dry ice additions. The results were presented of investigations concerning the usability of this method for the removal of those varnish coats that are used in motor industry
Thermal impact of the water-ice jet during the removal of varnish coats
W artykule omówiono oddziaływanie termiczne, jakie wywiera wysokociśnieniowa struga wodnolodowa na powłokę lakierniczą oraz materiał podłoża. Rozpatrzono kierunek rozchodzenia się ciepła zgodny z posuwem strugi oraz występujący w głąb materiału.The article covers a thermal impact of a high-pressure water-ice jet on the varnish coat and the base material. The direction was considered of the propagation of heat that is compliant with the jet feed and the one that occurs inside the material
Qualitative aspects of the removal of varnish with the water-ice jet
W artykule omówiono oddziaływanie wysokociśnieniowej strugi wodno-lodowej na powierzchnie lakiernicze. Zaprezentowano także rezultaty uzyskane w wyniku działania strugi na materiał podłoża po usunięciu powłok lakierniczych.This article covers the impact of a high-pressure jet on varnish surface. Furthermore, those results were presented that were obtained as a result of the action on the jet on the base material after the removal of varnish coats
An evaluation of the usefulness of using CO2 dry ice particles in surface treatment
W artykule przedstawiono wyniki termodynamicznych analiz cząstek suchego lodu w czasie kreowania wysokociśnieniowej strugi wodno-lodowej. Zaprezentowano efekty badań eksperymentalnych wpływu wydatku suchego lodu na wydajność usuwania powłok lakierniczych strugą wodno-lodową. Dokonano oceny stanu powierzchni podłoża, które po obróbce nie wykazuje żadnych zmian w stosunku do stanu pierwotnego.The paper covers theoretical analyses and experimental results aimed at an evaluation of the usefulness of CO2 dry ice particles for the removal of varnish coats. In the first section, there is performed a thermodynamic analysis of CO2 dry ice particles of the temperature lower than the sublimation temperature, during the creation of a water-ice jet. In this case, there was determined the impact of individual treatment parameters (Figs. 2 and 3) that are of significance to the mechanical properties of dry ice particles. Furthermore, a thermodynamic analysis of a high-pressure water-ice jet for ice particles of the temperature being equal to the sublimation temperature is conducted. It was established that during the transport of dry ice particles from a tank to a concentric multi-hole nozzle, a maximum of 4.7% of CO2 could be sublimated. Additionally, in a high-pressure water-ice jet, where 30% of dry ice will be sublimated, the water jet temperature will be reduced by a maximum of 1.03 K, when the initial air temperature is 293 K and the initial water temperature is also 293 K. In the further part of the paper, the influence of the dry ice expenditure on the treatment efficiency (Fig. 6) is discussed. There was found the occurrence of the maximum limiting expenditure of dry ice particles, with the use of which the best cleaning results are obtained. There was also carried out an analysis of the macro- and micro-structure of the substrate surface, from which varnish coats were removed with the aid of a high-pressure water-ice jet
Modeling of the undershot working system hydraulic excavators
W artykule przedstawiono modelowanie konstrukcji układu roboczego koparki hydraulicznej w wybranym programie typu CAD. Zaprezentowano poszczególne elementy składowe oraz wyniki badań wytrzymałościowych.This paper presents the modeling of construction of the hydraulic excavator working system in the CAD program. Presented individual components and the results of strength tests
Modeling motorcycle frame structure with electric drive
The article describes on the example of the motorcycle frame, the possibility of the use of CAD/CAE in the design process for part modeling and simulation of stresses occurring in them.W artykule, na przykładzie ramy motocykla, przedstawiono wykorzystanie w procesie projektowania systemów CAD/CAE do modelowania części i symulacji występujących w nich naprężeń
Interpretation of measurement results of surface coating removal efficiency by water-ice jet
W artykule przedstawiono wyniki pomiarów powierzchniowej wydajności usuwania powłok lakierniczych wysokociśnieniową strugą wodno-lodową przy zastosowaniu różnych dysz. Wyniki badań eksperymentalnych poddano aproksymacji z zastosowaniem iloczynu funkcji wykładniczych. Aproksymacje wykonano z zastosowaniem metody optymalizacji nieliniowej funkcji wielu zmiennych. Odpowiednio dobrana funkcja aproksymująca pozwoliła na ekstrapolację wyników i wybór dysz, które należy poddać dalszym badaniom.New realizations of technical coatings require regeneration of the structures already in service. In this case the significant importance is to carefully remove the old coating, to ensure intactness of the substrate material. One method is to use air jets doped ice particles, or jets such as the stream of cryogenic liquid nitrogen or ammonia. Measurements results of the surface coating removal efficiency by high-pressure stream of water ice using different nozzles are presented in the paper. It was found that irrespective of the pressure water jets, and expense of dry ice treatment, best performance is obtained for the four-hole nozzle having a hole diameter of water amounting to dw = 1,2 mm. Measurement results were approximated using the optimization method for the nonlinear function of many variables. Mathematical description of the measurement results by multiplying the efficiency ratio, ratio dependent on the pressure, and rate-dependent sufficient number of layers removed correctly is given in the paper (approximation error of about 9%). Suitably chosen approximating function allowed for the extrapolation and for the choice of nozzles. They should be subjected to further experiments. Research should be conducted for the maximum pressures possible to application, because the use of lower pressures is not justified in the described experiments. Extreme values of hole diameters less influence on pressure. Similarly, the layer number does not affects the value of the optimum parameters
Use of CAD systems on the example of construction crane folding with hydraulic drive
W artykule przedstawiono model konstrukcji składanego żurawia z napędem hydraulicznym wykonany w wybranym programie typu CAD. Zaprezentowane poszczególne elementy składowe żurawia ze szczególnym uwzględnieniem zastosowanych rozwiązań konstrukcyjnych.This paper presents a model of the construction crane folding with hydraulic drive made by CAD program. Presented individual crane components with particular reference to the solutions of construction
- …