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Background Recently, 5 randomized controlled trials confirmed the superiority of endovascular mechanical thrombectomy (EMT) to intravenous thrombolysis in acute ischemic stroke with large-vessel occlusion. The implication is that our health systems would witness an increasing number of patients treated with EMT. However, in-hospital delays, leading to increased time to reperfusion, are associated with poor clinical outcomes. This review outlines the in-hospital workflow of the treatment of acute ischemic stroke at a comprehensive stroke center and the lessons learned in reduction of in-hospital delays. Methods The in-hospital workflow for acute ischemic stroke was described from prehospital notification to femoral arterial puncture in preparation for EMT. Systematic review of literature was also performed with PubMed. Results The implementation of workflow streamlining could result in reduction of in-hospital time delays for patients who were eligible for EMT. In particular, time-critical measures, including prehospital notification, the transfer of patients from door to computed tomography (CT) room, initiation of intravenous thrombolysis in the CT room, and the mobilization of neurointervention team in parallel with thrombolysis, all contributed to reduction in time delays. Conclusions We have identified issues resulting in in-hospital time delays and have reported possible solutions to improve workflow efficiencies. We believe that these measures may help stroke centers initiate an EMT service for eligible patients. [ABSTRACT FROM AUTHOR]

The study here demonstrates the capability of thermography to detect and characterize pinhole defects in a visually transparent anti-reflection (AR) film. The diameter of the pin-holes varies from 0.03 mm to 4 mm. Each inspected area was unevenly heated for 65 s. Thermal images were processed by the following steps: de-trend processing, primary edge detection based on Sobel approximation, and further edge separation based on k-means clustering. Then, the diameter of pinholes was directly measured from binary images. The proposed image processing enables thermography to detect 86 of 90 inspected areas correctly in position. [ABSTRACT FROM AUTHOR]

Background: The initial factor in the occurrence, development, and prognosis of cerebral ischemia is vascular dysfunction in the brain, and vascular remodeling of the brain is the key therapeutic target and strategy for ischemic tissue repair. Catalpol is the main active component of the radix of Rehmannia glutinosa Libosch, and it exhibits potential pleiotropic protective effects in many brain-related diseases, including stroke.Purpose: The present study was designed to investigate whether catalpol protects vascular structure and promotes angiogenesis in cerebral ischemic rats and to identify its possible mechanisms in vivo and in vitro.Study Design: Cerebral ischemic rats and oxygen-glucose deprivation-exposed brain microvascular endothelial cells were used to study the therapeutic potential of catalpol in vivo and in vitro.Methods: First, neurological deficits, histopathological morphology, infarct volume, vascular morphology, vessel density, and angiogenesis in focal cerebral ischemic rats were observed to test the potential treatment effects of catalpol. Then, oxygen-glucose deprivation-exposed brain microvascular endothelial cells were used to mimic the pathological changes in vessels during ischemia to study the effects and possible mechanisms of catalpol in protecting vascular structure and promoting angiogenesis.Results: The in vivo results showed that catalpol reduced neurological deficit scores and infarct volume, protected vascular structure, and promoted angiogenesis in cerebral ischemic rats. The in vitro results showed that catalpol improved oxygen-glucose deprivation-induced damage and promoted proliferation, migration, and in vitro tube formation of brain microvascular endothelial cells. The HIF-1α (hypoxia-inducible factor 1α)/VEGF (vascular endothelial growth factor) pathway was activated by catalpol both in the brains of cerebral ischemic rats and in primary brain microvascular endothelial cells, and the activating effects of catalpol were inhibited by SU1498.Conclusion: The results of both the in vivo and in vitro studies proved that catalpol protects vascular structure and promotes angiogenesis in focal cerebral ischemic rats and that the mechanism is dependent on HIF-1α/VEGF. [ABSTRACT FROM AUTHOR]

• CFRP plates subjected to impact damage are inspected by THz imaging and VT. • Peak-time shift and independent component analysis are used in data processing. • The detection results of THz imaging and VT are quantitatively compared. In this paper, terahertz (THz) imaging and vibro-thermography (VT) are implemented for non-destructive evaluation (NDE) of CFRP subjected to impact damage. THz inspection is well-known for its outstanding detection depth in dielectric materials but unreliable in conductive materials like carbon fiber reinforced plastics (CFRP): an unwanted electro-magnetic wave will be excited under the irradiation of THz waves in conductive molecules and interrupted the reflective waves leading to a blur in the detection results. However, our experimental results showed THz imaging is comparable when it's used to detect surface defects and shallow ones caused by impact loads. We conducted a set of VT tests as a contrast test, and the VT data are processed by Fourier transform and eigenvector decomposition algorithms, i.e. independent component analysis (ICA). Compared with VT, THz imaging show more details on surface defects and shallow-buried ones due to the absence of thermal diffusion effects. THz imaging could perform non-invasive, non-ionizing and non-contact inspection on the impact damage based on the differences in reflective index. In the end, signal-to-noise (SNR) evaluation is used as an effective means to quantitatively compare the results of these two techniques. [ABSTRACT FROM AUTHOR]

Infrared imaging-based machine vision (IRMV) is the technology used to automatically inspect, detect, and analyse infrared images (or videos) obtained by recording the intensity of infrared light emitted or reflected by observed objects. Depending on whether controllable excitation is used during the imaging of infrared rays, thermal IRMV can be categorised into passive thermography and active thermography. Passive thermography is an important supplement to conventional machine vision based on visible light and is a valid imaging tool for self-heating objects such as the human body and electrical power devices. Active thermography is a non-destructive testing method for the quality evaluation and safety assurance of non-self-heating objects. In active thermography, the trend is to inspect rapidly, reliably, and intelligently by introducing multiple-mode excitation sources and artificial intelligence. The rapid development of deep learning makes IRMV more and more intelligent and highly automated, thus considerably increasing its range of applications. This paper reviews the principle, cameras, and thermal data of IRMV and discusses the applications of deep learning applied to IRMV. Case studies of IRMV and deep learning on various platforms such as unmanned vehicles, mobile phones and embedded systems are also reported. [ABSTRACT FROM AUTHOR]

Chansu is a traditional Chinese medicine that is generally recognized as a specific inhibitor of Na + /K + -ATPase. Bufalin, an active component of Chansu, is an endogenous steroid hormone with great potential as a cancer treatment. However, the mechanism by which it exerts its antitumor activity requires further research. Currently, the α1 subunit of Na + /K + -ATPase (ATP1A1) is known to exert important roles in tumorigenesis, and the precise mechanisms underlying the effect of Bufalin on the Na + /K + -ATPase α1 subunit was therefore investigated in this study to determine its role in glioblastoma treatments. The effect of ATP1A1 on the sensitivity of glioblastoma cells to Bufalin was investigated using MTT assays, RT-PCR and siRNA. Western blot was also used to explore the important roles of the ubiquitin-proteasome pathway in the Bufalin-mediated inhibition of ATP1A1. Xenografted mice were used to examine the anti-tumor activity of Bufalin in vivo . LC–MS/MS analysis was performed to determine the ability of Bufalin to traverse the blood-brain barrier (BBB). The results indicated that Bufalin inhibited the expression of ATP1A1 in glioblastoma by promoting the activation of proteasomes and the subsequent protein degradation of ATP1A1, while Bufalin had no effect on ATP1A1 protein synthesis. Bufalin also inhibited the expression of ATP1A1 in xenografted mice and significantly suppressed tumor growth. These data should contribute to future basic and clinical investigations of Bufalin. In conclusion, Bufalin significantly inhibited the expression of ATP1A1 in glioblastoma cells by activating the ubiquitin-proteasome signaling pathway. Bufalin may therefore have the potential to be an effective anti-glioma drug for human glioblastoma in the future. [ABSTRACT FROM AUTHOR]

5-Amino-1,3-dimethlybarbituric acid (5-amino-diMeBA), prepared form 1,3-dimethlybarbituric acid (diMeBA) via the functional group transformation strategy, is first used as the diazonium component to produce heterocyclic dyes, in order to expand the existing research objects in this area. Role-convert synthesis has been successfully achieved from a general coupling component diMeBA to a corresponding diazonium unit 5-amnio-diMeBA, and three pyrazolone/pyridone coupled bi-heterocyclic dyes were yielded. There are multiple possible azo/hydrazone tautomers for them since three ortho -carbonyl groups could serve as the protonated sites for active protons. The configurational confirmation depends on the precise location of heterocyclic hydroxyl groups, which could be deduced by comparing the alterations of two characteristic methyl single peaks in diMeBA moiety in the 1H NMR spectra before and after deprotonation. Our results reveal that three bi-heterocyclic dyes adopt the monohydrazone form in pyrazolone with 4-OH-diMeBA and the monohydrazone form in diMeBA with 6-OH-pyridone, respectively. Further UV–Vis spectra have been carried out to compare the delocalized π -conjugated system for them, together with three BA coupled heterocyclic dyes. In addition, solvatochromic and acid-base titration experiments were performed to verify the strength of intramolecular charge transfer within the whole molecules and the monohydrazone configuration for every bi-heterocyclic dye. [Display omitted] • 5-Amino-diMeBA was first used to synthesize three bi-heterocyclic dyes. • The configuration for these hydrazone dyes is confirmed by NMR and UV–Vis. • Solvatochromic and acid-base discoloration behaviors are studied. [ABSTRACT FROM AUTHOR]

In this paper, the ORC (Organic Rankine cycle) technology is adopted to recover the exhaust waste heat of diesel engine. The thermodynamic, economic and optimization models of the ORC system are established, respectively. Firstly, the effects of four key parameters, including evaporation pressure, superheat degree, condensation temperature and exhaust temperature at the outlet of the evaporator on the thermodynamic performances and economic indicators of the ORC system are investigated. Subsequently, based on the established optimization model, GA (genetic algorithm) is employed to solve the Pareto solution of the thermodynamic performances and economic indicators for maximizing net power output and minimizing total investment cost under diesel engine various operating conditions using R600, R600a, R601a, R245fa, R1234yf and R1234ze as working fluids. The most suitable working fluid used in the ORC system for diesel engine waste heat recovery is screened out, and then the corresponding optimal parameter regions are analyzed. The results show that thermodynamic performance of the ORC system is improved at the expense of economic performance. Among these working fluids, R245fa is considered as the most suitable working fluid for the ORC waste heat application of the diesel engine with comprehensive consideration of thermoeconomic performances, environmental impacts and safety levels. Under the various operating conditions of the diesel engine, the optimal evaporation pressure is in the range of 1.1 MPa–2.1 MPa. In addition, the optimal superheat degree and the exhaust temperature at the outlet of the evaporator are mainly influenced by the operating conditions of the diesel engine. The optimal condensation temperature keeps a nearly constant value of 298.15 K. [ABSTRACT FROM AUTHOR]

Abstract: A dynamic evaporator model of air source heat pump (ASHP), considering the ratio of the latent heat to sensible heat of wet air, is presented to analyze the performance of ASHP under frosting. The performance parameters, such as the heating capacity, COP and the outlet temperature of compressor, are simulated with CYCLEPAD. Then a semi-empirical correlation that predicts frost accumulation on the air-side of fin-tube heat exchanger is developed with dimensionless analysis and also modified by a test conducted under cold-moist conditions in winter. In addition, eight influence factors are considered involving the ambient conditions and structures of heat exchanger, whose effects are analyzed as well. Among them, the equivalent diameter of air flow cross-section in fin-tube deq is especially proposed. Lastly, the relationships between the ratio, the performance parameters and the frost accumulation are discussed in this paper, followed by an evaluation of an optimal defrosting time interval to improve the ASHP’s energy efficiency and operational reliability at cold-moist conditions in central-south China. [Copyright &y& Elsevier]