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101.
Rovee-Collier Carolyn; Schechter Amy; Shyi Gary C.; Shields Pamela J. 《Canadian Metallurgical Quarterly》1992,28(2):307
The contribution of specific contextual attributes to recognition of a well-learned cue was examined in 4 experiments with 6-mo-olds. 24 hrs after learning to move a given mobile in a distinctive visual surround by kicking, recognition of the training cue was tested in either the original context or in one in which only a single contextual attribute was altered. Retrieval was completely disrupted by all form changes involving the deletion of angles and by a chromatic figure/ground reversal, but a discriminable change in form color had no effect. Although infants displayed partial retention in a degraded context after 1 day, they displayed no retention when a reminder was administered in the same degraded context after 20 days. These data reveal that infants do not encode contextual information holistically; moreover, they imply a privileged status for highly specific information about the incidental setting in which an event occurs. Unless this same highly specific information is perceptually identified at the time of testing, the memory of that event will not be retrieved. Data are consistent with the hypothesis that the visual context serves as an initial attention gate for memory retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Lett Heather S.; Blumenthal James A.; Babyak Michael A.; Catellier Diane J.; Carney Robert M.; Berkman Lisa F.; Burg Matthew M.; Mitchell Pamela; Jaffe Allan S.; Schneiderman Neil 《Canadian Metallurgical Quarterly》2007,26(4):418
Objective: To compare the impact of network support and different types of perceived functional support on all-cause mortality or nonfatal reinfarction for patients with a recent acute myocardial infarction (AMI). Design: Participants were recruited from the Enhancing Recovery in Coronary Heart Disease (ENRICHD) trial; 2,481 AMI patients with depression or low social support were randomized to a cognitive-behavioral intervention or to a usual care control group. Data collection for certain measures of social support was limited: 2,466 participants completed the ENRICHD Social Support Inventory; 2,457 completed the Perceived Social Support Scale; 1,296 completed the Social Network Questionnaire; and 707 completed the Interpersonal Support and Evaluation List, Tangible Support subscale. Patients also completed the Beck Depression Inventory and were followed for up to 4.5 years. Main Outcome Measure: Time to death or nonfatal reinfarction. Results: Over the follow-up period, 599 patients (24%) died or had a nonfatal AMI. Survival models controlling age, sex, race, socioeconomic status, smoking, antidepressant use, and a composite measure of increased risk revealed that higher levels of perceived social support were associated with improved outcome for patients without elevated depression but not for patients with high levels of depression. Neither perceived tangible support nor network support were associated with more frequent adverse events. Conclusion: AMI patients should be assessed for multiple dimensions of perceived functional support and depression to identify those at increased psychosocial risk who may benefit from treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
104.
Mark H. Van Benthem Todd W. LaneRyan W. Davis Pamela D. LaneMichael R. Keenan 《Chemometrics and Intelligent Laboratory Systems》2011,106(1):115-124
Demand for a renewable liquid-phase fuel has reinvigorated interest in the development of novel biofuels from algae. The effects of fluctuating nutrients, temperature, and predation which arise in algal aquaculture necessitate novel analytical methods to assess and optimize the health of these cultures. In this article we describe the use of trilinear modeling to these ends, using imaging data of endogenous fluorescence from the marine diatom, Thalassiosira pseudonana, collected on a hyperspectral fluorescence confocal microscope (HSF-CM). By combining the spatial and spectral data with the additional physical parameter introduced by the varying photobleach rates of endogenous fluorophores, we obtain a means for employing trilinear analysis in this system. In this case, analysis was implemented using the method of parallel factors analysis (PARAFAC) which alleviates the rotational ambiguities involved in multivariate analysis of 2-way data. By imposing a nutrient limitation in our diatom culture, and collecting single cell microscopy data at various time points during the nutritional stress, PARAFAC results reveal evolution of the spectral emission characteristics of six components and a background as a result of incremental photobleaching. Although the underlying mechanisms for these observations are not addressed, the differences observed between nutritively normal and nutritively stressed cells provide signatures for early detection of health deterioration in the algal culture. Finally, the combination of hyperspectral fluorescence microscopy with PARAFAC is generally applicable for the study of complex biological systems with endogenous fluorescence. 相似文献
105.
106.
Riccardo Bernardini Roberto Rinaldo Andrea Vitali Pamela Zontone 《Signal, Image and Video Processing》2011,5(1):49-60
In this paper we propose and compare different distributed video coding (DVC) schemes based on the use of the wavelet transform,
which naturally allows for spatial and other forms of scalability. In particular, we propose a hybrid encoder which utilizes
channel codes, and evaluate its performance in the absence of a feedback channel. The proposed scheme uses statistical models
for the estimation of the required bitrate at the encoder. We also propose a scheme that is based on a modulo reduction procedure
and does not use channel codes at the receiver/transmitter. These schemes are compared with more conventional coders that
do not or only partially exploit the distributed coding paradigm. Experimental results show that the considered schemes have
good performance when compared with similar asymmetric video compression schemes, and that DVC can be an interesting option
in appropriate scenarios. 相似文献
107.
Intersection crashes between cars and vulnerable road users (VRUs), such as pedestrians and bicyclists, often result in injuries and fatalities. Advanced driver assistance systems (ADASs) can prevent, or mitigate, these crashes. To derive functional requirements for such systems, an understanding of the underlying contributing factors and the context in which the crashes occur is essential. The aim of this study is to use microscopic and macroscopic crash data to explore the potential of information and warning providing ADASs, and then to derive functional sensor, collision detection, and human–machine interface (HMI) requirements. The microscopic data were obtained from the European project SafetyNet. Causation charts describing contributing factors for 60 car-to-VRU crashes had been compiled and were then also aggregated using the SafetyNet Accident Causation System (SNACS). The macroscopic data were obtained from the Swedish national crash database, STRADA. A total of 9702 crashes were analyzed. The results show that the most frequent contributing factor to the crashes was the drivers’ failure to observe VRUs due to reduced visibility, reduced awareness, and/or insufficient comprehension. An ADAS should therefore help drivers to observe the VRUs in time and to enhance their ability to interpret the development of events in the near future. The system should include a combination of imminent and cautionary collision warnings, with additional support in the form of information about intersection geometry and traffic regulations. The warnings should be deployed via an in-vehicle HMI and according to the likelihood of crash risk. The system should be able to operate under a variety of weather and light conditions. It should have the capacity to support drivers when their view is obstructed by physical objects. To address problems that vehicle-based sensors may face in this regard, the use of cooperative systems is recommended. 相似文献
108.
Panagiota Kakni Roman Truckenmüller Pamela Habibovi Martijn van Griensven Stefan Giselbrecht 《International journal of molecular sciences》2022,23(23)
The mammalian intestinal epithelium contains more immune cells than any other tissue, and this is largely because of its constant exposure to pathogens. Macrophages are crucial for maintaining intestinal homeostasis, but they also play a central role in chronic pathologies of the digestive system. We developed a versatile microwell-based intestinal organoid-macrophage co-culture system that enables us to recapitulate features of intestinal inflammation. This microwell-based platform facilitates the controlled positioning of cells in different configurations, continuous in situ monitoring of cell interactions, and high-throughput downstream applications. Using this novel system, we compared the inflammatory response when intestinal organoids were co-cultured with macrophages versus when intestinal organoids were treated with the pro-inflammatory cytokine TNF-α. Furthermore, we demonstrated that the tissue-specific response differs according to the physical distance between the organoids and the macrophages and that the intestinal organoids show an immunomodulatory competence. Our novel microwell-based intestinal organoid model incorporating acellular and cellular components of the immune system can pave the way to unravel unknown mechanisms related to intestinal homeostasis and disorders. 相似文献
109.
Stefanie A. Khler Lisa Brandl Pamela L. Strissel Laura Gloßner Arif B. Ekici Miriam Angeloni Fulvia Ferrazzi Veronika Bahlinger Arndt Hartmann Matthias W. Beckmann Markus Eckstein Reiner Strick 《International journal of molecular sciences》2022,23(18)
Methylene blue (MB) is a dye used for histology with clinical importance and intercalates into nucleic acids. After MB staining of formalin fixed paraffin embedded (FFPE) muscle invasive bladder cancer (MIBC) and normal urothelium, specific regions could be microdissected. It is not known if MB influences RNA used for gene expression studies. Therefore, we analyzed MIBC using five different RNA isolation methods comparing patient matched FFPE and fresh frozen (FF) tissues pre-stained with or without MB. We demonstrate a positive impact of MB on RNA integrity with FF tissues using real time PCR with no interference of its chemical properties. FFPE tissues showed no improvement of RNA integrity, which we propose is due to formalin induced nucleotide crosslinks. Using direct multiplex RNA hybridization the best genes for normalization of MIBC and control tissues were identified from 34 reference genes. In addition, 5SrRNA and 5.8SrRNA were distinctive reference genes detecting <200 bp fragments important for mRNA analyses. Using these normalized RNAs from MB stained MIBC and applying multiplex RNA hybridization and mRNA sequencing, a minimal gene expression panel precisely identified luminal and basal MIBC tumor subtypes, important for diagnosis, prognosis and chemotherapy response. 相似文献
110.
Tamara T. Haque Pamela A. Frischmeyer-Guerrerio 《International journal of molecular sciences》2022,23(18)
Mast cells (MC) are a key effector cell in multiple types of immune responses, including atopic conditions. Allergic diseases have been steadily rising across the globe, creating a growing public health problem. IgE-mediated activation of MCs leads to the release of potent mediators that can have dire clinical consequences. Current therapeutic options to inhibit MC activation and degranulation are limited; thus, a better understanding of the mechanisms that regulate MC effector functions in allergic inflammation are necessary in order to develop effective treatment options with minimal side effects. Several cytokines have been identified that play multifaceted roles in regulating MC activation, including TGFβ, IL-10, and IL-33, and others that appear to serve primarily anti-inflammatory functions, including IL-35 and IL-37. Here, we review the literature examining cytokines that regulate MC-mediated allergic immune responses. 相似文献