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排序方式: 共有1745条查询结果,搜索用时 15 毫秒
31.
Shang L Jasiobedzki P Greenspan M 《IEEE transactions on pattern analysis and machine intelligence》2007,29(6):976-989
A method is presented for tracking 3D objects as they transform rigidly in space within a sparse range image sequence. The method operates in discrete space and exploits the coherence across image frames that results from the relationship between known bounds on the object's velocity and the sensor frame rate. These motion bounds allow the interframe transformation space to be reduced to a reasonable and indeed tiny size, comprising only tens or hundreds of possible states. The tracking problem is in this way cast into a classification framework, effectively trading off localization precision for runtime efficiency and robustness. The method has been implemented and tested extensively on a variety of freeform objects within a sparse range data stream comprising only a few hundred points per image. It has been shown to compare favorably against continuous domain iterative closest point (ICP) tracking methods, performing both more efficiently and more robustly. A hybrid method has also been implemented that executes a small number of ICP iterations following the initial discrete classification phase. This hybrid method is both more efficient than the ICP alone and more robust than either the discrete classification method or the ICP separately 相似文献
32.
This paper considers methods for knowledge exploitation in security policies for Service-Oriented Architecture (SOA) environments, discovering the modality conflicts in particular. Two algorithms for discovering SOA-specific modality conflicts are proposed. First, a trivial (ad-hoc) approach is presented and further extended by the improved algorithm which offers lower time complexity. The formal verification of the proposal is followed by experimental results confirming the expected supremacy of the improved algorithm. 相似文献
33.
Verleger Rolf; Ja?kowski Piotr; Aydemir Ayta?; van der Lubbe Rob H. J.; Groen Margriet 《Canadian Metallurgical Quarterly》2004,133(4):494
In general, both consciously and unconsciously perceived stimuli facilitate responses to following similar stimuli. However, masked arrows delay responses to following arrows. This inverse priming has been ascribed to inhibition of premature motor activation, more recently even to special processing of nonconsciously perceived material. Here, inverse priming depended on particular masks, was insensitive to contextual requirements for increased inhibition, and was constant across response speeds. Putative signs of motor inhibition in the electroencephalogram may as well reflect activation of the opposite response. Consequently, rather than profiting from inhibition of primed responses, the alternative response is directly primed by perceptual interactions of primes and masks. Thus there is no need to assume separate pathways for nonconscious and conscious processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Piotr Stasiak Dominika Ka
mierczak Karol Jopek Micha Nowicki Marcin Rucinski Radosaw Januchowski 《International journal of molecular sciences》2022,23(10)
Epithelial ovarian cancer has the highest mortality among all gynecological malignancies. The main reasons for high mortality are late diagnosis and development of resistance to chemotherapy. Resistance to chemotherapeutic drugs can result from altered expression of drug-resistance genes regulated by miRNA. The main goal of our study was to detect differences in miRNA expression levels in two doxorubicin (DOX)- and two topotecan (TOP)-resistant variants of the A2780 drug-sensitive ovarian cancer cell line by miRNA microarray. The next aim was to recognize miRNAs as factors responsible for the regulation of drug-resistance genes. We observed altered expression of 28 miRNA that may be related to drug resistance. The upregulation of miR-125b-5p and miR-935 and downregulation of miR-218-5p was observed in both DOX-resistant cell lines. In both TOP-resistant cell lines, we noted the overexpression of miR-99a-5p, miR-100-5p, miR-125b-5p, and miR-125b-2-3p and decreased expression of miR-551b-3p, miR-551b-5p, and miR-383-5p. Analysis of the targets suggested that expression of important drug-resistant genes such as the collagen type I alpha 2 chain (COL1A2), protein Tyrosine Phosphatase Receptor Type K (PTPRK), receptor tyrosine kinase—EPHA7, Roundabout Guidance Receptor 2 (ROBO2), myristoylated alanine-rich C-kinase substrate (MARCK), and the ATP-binding cassette subfamily G member 2 (ABCG2) can be regulated by miRNA. 相似文献
35.
Maciej Dulewicz Agnieszka Kulczyska-Przybik Piotr Mroczko Johannes Kornhuber Piotr Lewczuk Barbara Mroczko 《International journal of molecular sciences》2022,23(15)
Alzheimer’s disease (AD) is a progressive condition and the most common cause of dementia worldwide. The neuropathological changes characteristic of the disorder can be successfully detected before the development of full-blown AD. Early diagnosis of the disease constitutes a formidable challenge for clinicians. CSF biomarkers are the in vivo evidence of neuropathological changes developing in the brain of dementia patients. Therefore, measurement of their concentrations allows for improved accuracy of clinical diagnosis. Moreover, AD biomarkers may provide an indication of disease stage. Importantly, the CSF biomarkers of AD play a pivotal role in the new diagnostic criteria for the disease, and in the recent biological definition of AD by the National Institute on Aging, NIH and Alzheimer’s Association. Due to the necessity of collecting CSF by lumbar puncture, the procedure seems to be an important issue not only from a medical, but also a legal, viewpoint. Furthermore, recent technological advances may contribute to the automation of AD biomarkers measurement and may result in the establishment of unified cut-off values and reference limits. Moreover, a group of international experts in the field of AD biomarkers have developed a consensus and guidelines on the interpretation of CSF biomarkers in the context of AD diagnosis. Thus, technological advancement and expert recommendations may contribute to a more widespread use of these diagnostic tests in clinical practice to support a diagnosis of mild cognitive impairment (MCI) or dementia due to AD. This review article presents up-to-date data regarding the usefulness of CSF biomarkers in routine clinical practice and in biomarkers research. 相似文献
36.
Mateusz Sypniewski Zbigniew J. Krl Joanna Szyda Elbieta Kaja Magdalena Mroczek Tomasz Suchocki Adrian Lejman Maria Stpie Piotr Topolski Maciej Dbrowski Krzysztof Kotlarz Angelika Aplas Micha Wasiak Marzena Wojtaszewska Pawe Zawadzki Agnieszka Pawlak Robert Gil Paula Dobosz Joanna Stojak 《International journal of molecular sciences》2022,23(15)
Background: Severe outcomes of COVID-19 account for up to 15% of all cases. The study aims to check if any gene variants related to cardiovascular (CVD) and pulmonary diseases (PD) are correlated with a severe outcome of COVID-19 in a Polish cohort of COVID-19 patients. Methods: In this study, a subset of 747 samples from unrelated individuals collected across Poland in 2020 and 2021 was used and whole-genome sequencing was performed. Results: The GWAS analysis of SNPs and short indels located in genes related to CVD identified one variant significant in COVID-19 severe outcome in the HADHA gene, while for the PD gene panel, we found two significant variants in the DRC1 gene. In this study, both potentially protective and risk variants were identified, of which variants in the HADHA gene deserve the most attention. Conclusions: This is the first study reporting the association between the HADHA and DRC1 genetic variants and COVID-19 severe outcome based on the cohort WGS analysis. Although all the identified variants are localised in introns, they may be correlated and therefore inherited along with other risk variants, potentially causative to severe outcome of COVID-19 but not discovered yet. 相似文献
37.
爱立信IMS weShare业务有20%的开发与用户视觉体验相关(用户界面、图标、标签以及进度条),其它的80%则主要致力于设备间的系统.与此相对比,用户的体验则完全(100%)有赖于其可接触的事物. 相似文献
38.
Hillock growth kinetics and size distribution were investigated in Al, Al:Si 1% and Al:Si1%:Cu 0.5% layers. Metallization surface was examined by optical, SEM and TEM microscopy, stylus profiling and an automatic method of hillock recognition from a microscope image. The method allowed for counting hillocks in a desired range of their diameter d. Surface density of hillocks was measured as a function of time of furnace annealing at 400°C and as a function of temperature of RTP annealing. A maximum hillock size was found to increase linearly with metallization layer thickness and with logarithm of annealing time. A total area occupied by hillocks was evaluated. Hillock density decreased versus 1/T with an activation energy of 0.28 eV for Al and 0.31 eV for Al:Si. It was found, that a normalized hillock density N may be expressed by a formula N=N0 exp(−cd). Values for N0 and c are given together with a short discussion. 相似文献
39.
Anna Ciechanowska Ilona M. Gora Stanislawa Sabalinska Piotr Ladyzynski 《International journal of molecular sciences》2022,23(12)
Diabetes mellitus causes endothelial dysfunction. The aim of this study was to investigate the effect of normal (5 mmol/L), high (20 mmol/L), and fluctuating (5 and 20 mmol/L changed every day) glucose concentration in the culture medium on the viability of human umbilical vein endothelial cells (HUVECs) co-cultured with human umbilical artery smooth muscle cells (HUASMCs). The cultures were conducted on semi-permeable flat polysulfone (PSU) fibronectin-coated membranes immobilized in self-made inserts. The insert contained either HUVECs on a single membrane or HUASMCs and HUVECs on two membranes close to each other. Cultures were conducted for 7 or 14 days. Apoptosis, mitochondrial potential, and the production of reactive oxygen species and lactate by HUVECs were investigated. The results indicate that fluctuations in glucose concentration have a stronger negative effect on HUVECs viability than constant high glucose concentration. High and fluctuating glucose concentrations slow down cell proliferation compared to the culture carried out in the medium with normal glucose concentration. In conclusion, HUASMCs affect the viability of HUVECs when both types of cells are co-cultured in medium with normal or variable glucose concentration. 相似文献
40.
Joanna ebrowska Olga onierkiewicz Magorzata Ponikowska Micha Puchalski Natalia Krawczun Joanna Makowska Piotr Skowron 《International journal of molecular sciences》2022,23(14)
The obligatory step in the life cycle of a lytic bacteriophage is the release of its progeny particles from infected bacterial cells. The main barrier to overcome is the cell wall, composed of crosslinked peptidoglycan, which counteracts the pressure prevailing in the cytoplasm and protects the cell against osmotic lysis and mechanical damage. Bacteriophages have developed two strategies leading to the release of progeny particles: the inhibition of peptidoglycan synthesis and enzymatic cleavage by a bacteriophage-coded endolysin. In this study, we cloned and investigated the TP84_28 endolysin of the bacteriophage TP-84, which infects thermophilic Geobacillus stearothermophilus, determined the enzymatic characteristics, and initially evaluated the endolysin application as a non-invasive agent for disinfecting surfaces, including those exposed to high temperatures. Both the native and recombinant TP84_28 endolysins, obtained through the Escherichia coli T7-lac expression system, are highly thermostable and retain trace activity after incubation at 100 °C for 30 min. The proteins exhibit strong bacterial wall digestion activity up to 77.6 °C, decreasing to marginal activity at ambient temperatures. We assayed the lysis of various types of bacteria using TP84_28 endolysins: Gram-positive, Gram-negative, encapsulated, and pathogenic. Significant lytic activity was observed on the thermophilic and mesophilic Gram-positive bacteria and, to a lesser extent, on the thermophilic and mesophilic Gram-negative bacteria. The thermostable TP84_28 endolysin seems to be a promising mild agent for disinfecting surfaces exposed to high temperatures. 相似文献