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71.
Sagar Chhetri Abeer Alsadoon Thair Al‐Dala'in P. W. C. Prasad Tarik A. Rashid Angelika Maag 《Computational Intelligence》2021,37(1):578-595
Accurate fall detection for the assistance of older people is crucial to reduce incidents of deaths or injuries due to falls. Meanwhile, vision‐based fall detection system has shown some significant results to detect falls. Still, numerous challenges need to be resolved. The impact of deep learning has changed the landscape of the vision‐based system, such as action recognition. The deep learning technique has not been successfully implemented in vision‐based fall detection system due to the requirement of a large amount of computation power and requirement of a large amount of sample training data. This research aims to propose a vision‐based fall detection system that improves the accuracy of fall detection in some complex environments such as the change of light condition in the room. Also, this research aims to increase the performance of the pre‐processing of video images. The proposed system consists of Enhanced Dynamic Optical Flow technique that encodes the temporal data of optical flow videos by the method of rank pooling, which thereby improves the processing time of fall detection and improves the classification accuracy in dynamic lighting condition. The experimental results showed that the classification accuracy of the fall detection improved by around 3% and the processing time by 40–50 ms. The proposed system concentrates on decreasing the processing time of fall detection and improving the classification accuracy. Meanwhile, it provides a mechanism for summarizing a video into a single image by using dynamic optical flow technique, which helps to increase the performance of image preprocessing steps. 相似文献
72.
Adapting physico-chemical characterization techniques for in situ studies of real heterogeneous catalysts during conditioning, reaction, and deactivation processes is a research topic of growing importance. Up to now, in most studies only one single in situ technique is applied. However, new trends are focused on using a portfolio of several in situ methods to obtain comprehensive information on structure-reactivity relationships. This review discusses such application examples with the aim to point out the particular benefits that arise from multitechnique approaches for understanding processes like formation of active sites, interaction of those sites with reactant molecules, and catalyst deactivation. Except for Fourier-transform infrared spectroscopy and quasi-in situ X-ray photoelectron spectroscopy, the examples deal mainly with the combined use of bulk techniques such as electron paramagnetic resonance, ultraviolet/visible diffuse reflection spectroscopy, laser-Raman spectroscopy, temperature-programmed spectroscopy, X-ray diffraction, and X-ray absorption spectroscopy. However, although not being surface-sensitive per se, these techniques provide results relevant for the catalyzed reaction. Illustrative case studies comprise the investigation of (i) vanadia-based catalysts during selective oxidation and ammoxidation of toluene and during methanol synthesis, (ii) supported chromium oxides during octane aromatization, (iii) zeolite crystallization and catalysis, and (iv) a Cu/ZnO catalyst during methanol synthesis. 相似文献
73.
Eleni Lioliou Angelika Zimmermann Leslie Willcocks Lan Gao 《Information Systems Journal》2014,24(6):503-535
This study aims to contribute to the literature on IT outsourcing governance by advancing our understanding of mechanisms of substitution and complementarity between formal and relational governance. Our study illustrates certain conditions under which substitution and complementarity can occur and depicts a two‐way causal relationship between them. Our examination further provides a more in‐depth assessment of relational governance by using the concept of the psychological contract. Our results demonstrate that the psychologically binding nature of the psychological contract makes it a particularly forceful substitute to formal governance, while its associations with other relationship aspects make it a forceful complement. 相似文献
74.
Prior research has shown that the success of offshoring is affected by relational behaviours of the employees involved in an offshoring collaboration. However, hardly anything is known about the attitudes that onshore colleagues hold towards offshoring, and how such offshoring attitudes affect relational behaviours towards offshore colleagues. We therefore present an interpretivist, qualitative case study that explores the offshoring attitudes of German information technology developers. We found that offshoring attitudes affected relational behaviours towards Indian offshore colleagues, in terms of (1) treating Indian colleagues as fellow team members as opposed to suppliers; (2) spending more or less effort in communication and knowledge transfer; and (3) supporting vs. avoiding the task transfer. These relational behaviours fed back into participants' offshoring attitudes, leading to vicious and virtuous circles. The circles created two contrasting configurations of offshoring attitudes and relational behaviours, driven by opposing forces within the departmental context. Our findings highlight the value of taking a configurational perspective for understanding offshoring success and for identifying drivers that need to be managed in order to achieve favourable configurations. We suggest that future research should further expand the typology of attitude‐behaviour configurations and could apply theories of efficacy, self‐reinforcing spirals and planned behaviour. 相似文献
75.
Ulrich Sommer Tiziana Siciliano Celina Ebersbach Alicia-Marie K. Beier Matthias B. Stope Korinna Jhrens Gustavo B. Baretton Angelika Borkowetz Christian Thomas Holger H. H. Erb 《International journal of molecular sciences》2022,23(3)
Prostate-specific membrane antigen (PSMA) is an essential molecular regulator of prostate cancer (PCa) progression coded by the FOLH1 gene. The PSMA protein has become an important factor in metastatic PCa diagnosis and radioligand therapy. However, low PSMA expression is suggested to be a resistance mechanism to PSMA-based imaging and therapy. Clinical studies revealed that androgen receptor (AR) inhibition increases PSMA expression. The mechanism has not yet been elucidated. Therefore, this study investigated the effect of activation and inhibition of androgen signaling on PSMA expression levels in vitro and compared these findings with PSMA levels in PCa patients receiving systemic therapy. To this end, LAPC4, LNCaP, and C4-2 PCa cells were treated with various concentrations of the synthetic androgen R1881 and antiandrogens. Changes in FOLH1 mRNA were determined using qPCR. Open access databases were used for ChIP-Seq and tissue expression analysis. Changes in PSMA protein were determined using western blot. For PSMA staining in patients’ specimens, immunohistochemistry (IHC) was performed. Results revealed that treatment with the synthetic androgen R1881 led to decreased FOLH1 mRNA and PSMA protein. This effect was partially reversed by antiandrogen treatment. However, AR ChIP-Seq analysis revealed no canonical AR binding sites in the regulatory elements of the FOLH1 gene. IHC analysis indicated that androgen deprivation only resulted in increased PSMA expression in patients with low PSMA levels. The data demonstrate that AR activation and inhibition affects PSMA protein levels via a possible non-canonical mechanism. Moreover, analysis of PCa tissue reveals that low PSMA expression rates may be mandatory to increase PSMA by androgen deprivation. 相似文献
76.
Katarzyna Piechowska Angelika Baranowska-czkowska Krzysztof Z. czkowski Jolanta Konieczkowska Mariola Siwy Marharyta Vasylieva Pawe Gnida Pawe Nitschke Ewa Schab-Balcerzak 《International journal of molecular sciences》2022,23(10)
The paper presents synthesis and characterization of nine new thiazolyl-(phenyldiazenyl)-2H-chromen-2-one dyes. The impact of substituent structure in thiazole ring in the synthesized azocoumarin derivatives on electrochemical properties, photoisomerization process and photovoltaic response was examined. The dyes were electrochemically active and undergo reduction and oxidation processes. They showed low electrochemically estimated energy band gap in the range of 1.71–2.13 eV. Photoisomerization process of the synthesized molecules was studied in various solvents such as ethanol, chloroform and N,N-dimethylformamide (DMF) upon the UV illumination. It was found that novel azodyes showed reversible trans-cis-trans isomerization and exhibited long thermal back to the trans form, that was even 7 days in DMF. Selected azocoumarin were molecularly dispersed in polystyrene for preparation of guest-host azopolymer systems to study the cis-trans thermal isomerization of obtained dyes in solid state. The photovoltaic activity of the azochromophores was tested in bulk-heterojunction solar cells. They acting as weak donors in device with structure ITO/PEDOT:PSS/dye:PC70BM/Al. No photovoltaic response of cells with azocoumarin derivatives bearing 4-fluorobenzene, 3,4-dichlorobenzene, or 4-(1-adamantyl) unit was found. Additionally, dye which showed the best activity was examined in three-component solar cells ITO/PEDOT:PSS/PTB7:PC70BM:dye/PFN/Al. 相似文献
77.
Anna Mietelska-Porowska Justyna Domaska Andrew Want Angelika Wickowska-Gacek Dominik Chutoraski Maciej Koperski Urszula Wojda 《International journal of molecular sciences》2022,23(9)
The term Western diet (WD) describes the consumption of large amounts of highly processed foods, rich in simple sugars and saturated fats. Long-term WD feeding leads to insulin resistance, postulated as a risk factor for Alzheimer’s disease (AD). AD is the main cause of progressive dementia characterized by the deposition of amyloid-β (Aβ) plaques and neurofibrillary tangles consisting of the hyperphosphorylated tau (p-Tau) protein in the brain, starting from the entorhinal cortex and the hippocampus. In this study, we report that WD-derived impairment in insulin signaling induces tau and Aβ brain pathology in wild-type C57BL/6 mice, and that the entorhinal cortex is more sensitive than the hippocampus to the impairment of brain insulin signaling. In the brain areas developing WD-induced insulin resistance, we observed changes in p-Tau(Thr231) localization in neuronal subcellular compartments, indicating progressive tauopathy, and a decrease in amyloid precursor protein levels correlating with the appearance of Aβ peptides. These results suggest that WD promotes the development of AD and may be considered not only a risk factor, but also a modifiable trigger of AD. 相似文献
78.
H. G. O. Becker G. Israel Angelika Kalauch D. Pfeifer 《Advanced Synthesis \u0026amp; Catalysis》1982,324(6):947-954
Properties and Thermal Reactions from Complexes of Arene Diazonium Salts with Crown Ethers In contrast to 18-crown-6, the substituted crown ethers Benzo-18-crown-6, Dibenzo-18-crown-6, and Naphtho-18-crown-6 form in solution complexes with p-CH3 C6H4 N2+BF4-characterized by a broad charge transfer absorption up to 550 nm. The formation constants lg Kc are 2,32 2,16 and 1,44 for Benzo-, Dibenzo-, and Naphtho-18-crown-6, respectively. Formation enthalpy ΔH = −7,5 kJ/mol and entropy ΔS = +18 J/K mol are measured in the case of p-Cl C6H4 N2+BF4− and Dibenzo-18-crown-6 (20°). Kc depends on substituents in the arene ring of the diazonium salt; ϱ = +0,8. Thermal dediazoniation in the presence of Crown ethers results in high yields of the corresponding arene. This is explained by a fast radical chain reaction between the diazonium salt and the polyether (Meerwein-Reduction). 相似文献
79.
Katrin Kittler Monika Schreiner Angelika Krumbein Stefanie Manzei Matthias Koch Sascha Rohn Ronald Maul 《Food chemistry》2012
Toxin-producing cyanobacterial species are increasingly being found in freshwater systems. However, literature on the impact of many cyanobacterial toxins on plants is scarce. Cylindrospermosin (CYN), a secondary metabolite of cyanobacteria such as Cylindrospermopsis and Aphanizomenon species, is a potent hepatotoxin and protein synthesis inhibitor. Worryingly, CYN is increasingly found in surface and drinking water worldwide causing human and animal intoxications. Further, exposure of crop plants to CYN by irrigation with contaminated water has already been shown. Therefore, in this study, horticulturally important and highly consumed Brassica species were investigated to determine the level of CYN in the leaves after exposure of the roots to the toxin. Treatment of Brassica oleracea var. sabellica, Brassica juncea, and Sinapis alba under varying experimental conditions showed significant CYN uptake, with CYN levels ranging from 10% to 21% in the leaves compared to the CYN concentration applied to the roots (18–35 μg/l). In seedlings, CYN concentrations of up to 49 μg/g fresh weight were observed. Thus, crop plants irrigated with CYN-containing water may represent a significant source of this toxin within the food chain. 相似文献
80.
Stephanie Eichhorn Angelika Hrschlger Markus Steiner Josef Laimer Bettina M Jensen Serge A Versteeg Isabel Pablos Peter Briza Laurian Jongejan Neil Rigby Juan A Asturias Antonio Portols Montserrat Fernandez‐Rivas Nikolaos G Papadopoulos Adriano Mari Lars K Poulsen Peter Lackner Ronald van Ree Fatima Ferreira Gabriele Gadermaier 《Molecular nutrition & food research》2019,63(18)