Void defects behind the linings are typical in most operating tunnels, and effective methods are needed to identify them. This study presents a self-developed non-destructive detection method called ...transient electromagnetic radar (TER). Measures and algorithms were proposed to improve TER according to the characteristics of the composite lining. The detection depth was increased by adjusting the transmitter current and reducing the primary magnetic field turn-off time. The image resolution was improved using the transient electromagnetic signal enhancement algorithm. Data noise was suppressed using the hybrid algorithm of bipolar superposition and multi-period sampling. The improved TER was subjected to indoor physical model tests and try-outs in a defective railway tunnel to evaluate its actual detection capacity. The results showed that the improved TER had excellent distinguishing capacities on lining-related media and boundaries between different lining layers. It was capable of effectively detecting void defects over 10 cm in size behind the linings. Compared with ground-penetrating radar (GPR), TER is less interfered with by steel bars, and the radar image is more intuitive and clearer. The actual features of the void defects were more accurately reflected with the TER approach, indicating its great superiority in the recognition capacity. This study could help the evaluation of void defects and the subsequent maintenance.
•A new non-destructive detecting technology suitable for composite linings is proposed.•Easily to distinguish medium related to composite lining by the variation of apparent resistivity.•The effective detection of void defects over 10 cm in size behind the lining is realized by TER.
Motivations and place attachment constructs have been previously used as antecedents of behavioral intentions regarding a destination. Nevertheless, previous studies investigating behavioral ...intention models have paid little attention to the influence of motivations on place attachment and the influence of place attachment on behavioral intentions within the same structural model. This article develops an integrated model to investigate these relationships. Data were collected from recreational scuba divers in Catalonia, Spain. The results suggest that personal escape and personal seeking are the main motivations, and these factors influence place dependence and place identity. Other findings indicate that place dependence influences behavioral intentions more than place identity. In addition, the level of involvement in the activity moderates the links between constructs in some of the relationships.
Background and Objective: With the expansion of urbanization and the development of industry, environmental pollution, including sources of drinking water to heavy metals, has become a global ...problem. Therefore, the present study was conducted to measure the concentration of lead and cadmium in the water of Gorgan distribution network. Materials and Methods: This is a descriptive cross-sectional study in which the concentrations of heavy metals lead and cadmium were measured in 25 different stations of the Gorgan drinking water distribution network from April to September 2018 by atomic absorption device. Statistical analysis was used from SPSS ver 22 software. Also, zoning maps based on the concentration of these two metals were prepared by Geographic Information System (GIS) software. Results: The results of measuring the lead and cadmium concentration showed that all measured values are less than national and international standards. In general, the average concentrations of lead and cadmium were 4.38 and 0.1 μg/L, respectively. The results of Kruskal-Wallis test showed that there was a significant difference (p <0.01) between the concentrations obtained from lead metal in different months. Additionally, the distribution map of this lead and cadmium exhibited that in the central areas and some border areas, the concentration of these two metals is higher. Conclusion: According to the obtained results, it can be seen that the concentration of heavy metals lead and cadmium in the water of Gorgan distribution network is within the permitted standards.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
In vitro blood-brain barrier (BBB) models have been widely used to simulate in vivo models due to their low cost, feasibility, and repeatability. To serve as a valid substitute, the in vitro BBB ...should have the similar barrier function as that in vivo. This chapter summarizes the detailed methods for quantifying the barrier function, e.g., the permeability of the BBB to water, ions, and solutes for an in vitro BBB generated on the Transwell filter.
The present study investigates wavenumber‐4 (wave‐4) structure in the longitude variation of zonal and meridional winds observed by the Michelson Interferometer for Global High‐resolution ...Thermospheric Imaging (MIGHTI) instrument onboard the Ionospheric Connection Explorer (ICON) satellite. The amplitude of the wave‐4 pattern in meridional wind displays semi‐annual variation with equinoctial maxima whereas its seasonal variation in zonal wind shows maxima during August–October at the equatorial and low latitudes. The wave‐4 longitude variation maximizes at lower thermospheric heights (below 130 km) in zonal and meridional winds. It is considered primarily driven by the non‐migrating eastward propagating diurnal tide with zonal wavenumber‐3 (DE3) in the zonal wind. However, the amplitude of DE3 tide in the meridional wind does not show any enhancement during September–October. The seasonal variations of the wave‐4 amplitude and the DE3 tide are not similar in the zonal and meridional winds. The migrating ter‐diurnal tide (TW3) exhibits significant amplitudes during March–April and September–November in the meridional wind. In addition, the latitude variation of non‐migrating TE1 tide shows maximum amplitude during September–October. These results suggest that the non‐linear interaction between the TW3 and TE1 tides can serve as a potential source for the wave‐4 longitude variation in the meridional wind at lower thermospheric altitudes.
Plain Language Summary
The four peaked longitudinal structure observed in ionosphere and thermosphere has long been investigated to determine its seasonal and inter‐annual variability in many parameters, as well as its sources, which can be of lower atmospheric origin. Earlier studies have shown that wave‐4 structure in the longitude variation of thermospheric zonal wind has large amplitudes between June and October. The investigation of ICON‐MIGHTI zonal wind confirms this. The wave‐4 pattern in the longitude variation of the meridional wind reveals that it has maxima during equinox different from the zonal wind. The DE3 tide is the primary contributor to the wave‐4 pattern in zonal wind. The DE3 shows large amplitudes during March–April however, it is weak during September–October in meridional wind. The source of wave‐4 pattern in the meridional wind is investigated. In meridional wind, the seasonal variation of migrating ter‐diurnal TW3 tide shows large amplitudes (40 m/s) during March–April and September–November. The non‐migrating ter‐diurnal TE1 tide shows enhanced amplitudes during September–October which suggests that the non‐linear interaction between the TW3 and TE1 tides can generate wave‐4 longitude structure in meridional wind at lower thermospheric altitudes. This study indicates the existence of other possible sources for the wave‐4 pattern observed in thermosphere.
Key Points
Wave‐4 longitude structure in thermospheric meridional wind shows semi‐annual variation with equinoctial maxima at 100–110 km
Though DE3 tide does not show any enhancement during September–October, TW3 tide is found to be dominant in the meridional wind
It is suggested that the non‐linear interaction between TW3 and TE1 tides can generate wave‐4 structure in thermospheric meridional wind
The potential application of a single Fe atom decorated C24N24 fullerene (Fe@C24N24) as a highly active catalyst for the CO oxidation is investigated through the dispersion-corrected DFT ...calculations. Three different CO oxidation reaction pathways, including the Eley-Rideal (ER), the Langmuir-Hinshelwood (LH) and the termolecular Eley-Rideal (TER) are investigated comparably. Our results indicate that the CO oxidation would like to occur via the TER mechanism owing to its small activation energies. The calculated energy barrier for the rate-determining step of the TER pathway is 0.35 eV. The results reveal that Fe@C24N24 can be regarded as an innovative metal-free catalyst for the low temperature oxidation of toxic CO.
Display omitted
•The adsorption behaviors of O2 and CO molecules over the Fe@C24N24 were discussed.•Fe@C24N24 as a highly active catalyst for the oxidation of CO•TER mechanism is the most energetically favorable one for the oxidation of CO over Fe@C24N24.
OBJECTIVES:We assessed the effectiveness of ToT from VR laparoscopic simulation training in 2 studies. In a second study, we also assessed the TER. ToT is a detectable performance improvement between ...equivalent groups, and TER is the observed percentage performance differences between 2 matched groups carrying out the same task but with 1 group pretrained on VR simulation. Concordance between simulated and in-vivo procedure performance was also assessed.
DESIGN:Prospective, randomized, and blinded.
PARTICIPANTS:In Study 1, experienced laparoscopic surgeons (n = 195) and in Study 2 laparoscopic novices (n = 30) were randomized to either train on VR simulation before completing an equivalent real-world task or complete the real-world task only.
RESULTS:Experienced laparoscopic surgeons and novices who trained on the simulator performed significantly better than their controls, thus demonstrating ToT. Their performance showed a TER between 7% and 42% from the virtual to the real tasks. Simulation training impacted most on procedural error reduction in both studies (32- 42%). The correlation observed between the VR and real-world task performance was r > 0·96 (Study 2).
CONCLUSIONS:VR simulation training offers a powerful and effective platform for training safer skills.
OPTN/SRTR 2017 Annual Data Report: Pancreas Kandaswamy, R.; Stock, P. G.; Gustafson, S. K. ...
American journal of transplantation,
February 2019, 2019-02-00, 20190201, Letnik:
19, Številka:
S2
Journal Article
Recenzirano
Odprti dostop
In 2017, 1492 patients were added to the pancreas transplant waiting list, 964 listed as active, a slight increase from 2016. This is significant because for the first time in the past decade, the ...steady downward trend in additions to the waiting list has been reversed. Proportions of pancreas donors with cerebrovascular accident as cause of death decreased, with a concomitant increase in proportions with anoxia and head trauma. This is partly a result of the national opioid crisis, and it reflects increasing use of younger donors for pancreas transplant. The 2017 outcome report remains compromised by previous variation in reporting graft failure. Although the OPTN Pancreas Transplantation Committee has approved more precise definitions of pancreas graft failure, implementation of these definitions took place recently, and the data are not reflected in this report.
A CP2–127–06 Melcor module is incorporated into a radiative cooling (RC) system to work as a thermoelectric refrigerator (TER) at daytime and a thermoelectric generator (TEG) in nighttime. Through ...analysis of the single RC system, only a small temperature span between environment and building can be achieved. However, the temperature span can be significantly improved by combining RC and TER. The TER's input electrical current is optimized to obtain the maximum coefficient of performance (COP) 4.85 and the maximum cooling power density (CPD) 9.64 × 103 W m−2. Making trade-off between COP and CPD, the optimal regions of the COP, CPD, temperatures of cold side and hot side, and electrical current are determined. Further, the RC-TEG system's maximum power density 5.10 W m−2 and maximum efficiency 0.369% and the corresponding optimal conditions are obtained. With increasing the area ratio of emitter to TER or TEG, the performances of the systems are firstly improved and then remain almost unchanged. This work may provide guidance for building's thermal management at daytime and power generation in nighttime.
•Two RC-TER and RC-TEG systems are constructed by utilizing CP2–127–06 Melcor module.•Thermal-electrical coupling properties and parametric optimal designs are studied.•TER's maximum COP 4.47 and CPD 3.11 × 103 W m−2 are obtained under given conditions.•RC-TEG system's maximum power density 4.78 W m−2 and efficiency 0.418% are obtained.•Basis for building's cooling at daytime and power generation in nighttime are provided.
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