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Mechanisms underlying the protective effects of blueberry extract against ultraviolet radiation in a skin cell co-culture system
摘要： Ultraviolet radiation induces skin damage, inflammation, and aging. To explore the protective effects of blueberry extract (BE) against ultraviolet-C (UV-C) radiation, we analysed human skin keratinocyte (HaCaT) and human foreskin fibroblast (HFF) cells alone or in a co-culture, treated or not with BE, after exposure to UV-C. Surprisingly, MMP-1 was significantly up-regulated in HFF cells and in the co-cultured cell group in response to UV-C irradiation (8 mJ/cm2), but not in HaCaT cells. As expected, BE had a significantly protective effects; it decreased DNA fragmentation and inhibited MMP-1 and inflammatory factors expression in response to UV-C radiation. In addition, BE reduced the accumulation of proteins (MMP-1, c-fos, and c-jnu) in the MAPK (mitogen-activated protein kinase) pathway after UV-C radiation. Taken together, these results showed that BE exerted a protective effect against UV-C irradiation, and modulated MMP-1 production through MAPK signalling by direct and indirect pathways in HaCaT and HFF cells.
关键词： UVC,MAPK signals,Anti-ultraviolet,Co-culture models,Blueberry extracts
更新于2025-09-09 09:28:46
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Using reflectance to explain vegetation biochemical and structural effects on sun-induced chlorophyll fluorescence
摘要： The growing availability of global measurements of sun-induced chlorophyll fluorescence (SIF) can help in improving crop monitoring, especially the monitoring of photosynthetic activity. However, variations in top-of-canopy (TOC) SIF cannot be directly interpreted as physiological changes because of the confounding effects of vegetation biochemistry (i.e. pigments, dry matter and water) and structure. In this study, we propose an approach of using radiative transfer models (RTMs) and TOC reflectance to estimate the biochemical and structural effects on TOC SIF, as a necessary step in retrieving physiological information from TOC SIF. The approach was assessed by using airborne (HyPlant) reflectance and SIF data acquired over an agricultural experimental farm in Germany on two days, before and during a heat event in summer 2015 with maximum temperatures of 27°C and 34°C, respectively. The results show that over 76% variation among different crops in SIF observations was explained by variation in vegetation biochemistry and structure. In addition, the changes of vegetation biochemistry and structure explained as much as 73% variation between the two days in far-red SIF, and 40% variation in red SIF. The remaining unexplained variation was mostly attributed to the variability in physiological status. We conclude that reflectance provides valuable information to account for biochemical and structural effects on SIF and to advance analysis of SIF observations. The combination of RTMs, reflectance and SIF opens new pathways to detect vegetation biochemical, structural and physiological changes.
关键词： Canopy structure,Radiative transfer models,Chlorophyll fluorescence,HyPlant,Airborne,Reflectance
更新于2025-09-09 09:28:46
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Study on a Twice Transfer Alignment Based on Dual Model
摘要： This paper proposes a twice rapid transfer alignment algorithm based on dual models in order to solve the problems such as long convergence time, poor accuracy, and heavy computation burden resulting from the traditional nonlinear error models. The quaternion matching method based on quaternion error model along with the extended Kalman filter (EKF) is applied to deal with the large misalignment in the first phase. Then in the second transfer alignment phase, velocity plus attitude matching method as well as classical Kalman filter is adopted. The simulation and the results of vehicle tests demonstrate that this method combines the advantages of both nonlinear and linear error models with the guarantee of accuracy and fastness.
关键词： quaternion error model,extended Kalman filter,transfer alignment,dual models,velocity plus attitude matching
更新于2025-09-09 09:28:46
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[Systems & Control: Foundations & Applications] Uncertainty in Complex Networked Systems (In Honor of Roberto Tempo) || Networked Quantum Systems
摘要： This chapter presents a survey of results in the area of networked quantum systems. The chapter includes background material on quantum linear system models and finite level quantum system models. Different forms of these models are discussed and the issue of physical realizability is addressed. Also, the Kalman decomposition for linear quantum systems is described. The use of optical linear quantum networks in the physical realization of quantum systems is discussed for both the passive and non-passive case.
关键词： networked quantum systems,finite level quantum system models,quantum linear system models,Kalman decomposition,physical realizability,optical linear quantum networks
更新于2025-09-04 15:30:14
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Sensing Multi Business Model Innovationvia Advanced Sensor Technology
摘要： The ability to innovate Business Models (BM) and do Multi Business Model Innovation (MBMI) has become more complicated today, but also a very hot topic in many businesses and even for governments. As BM’s lifetime are becoming shorter and shorter, BM’s are also changing typologies and a larger part of these becomes disruptive. Danish Government already in 2017 formed a disruption council – as a reflection on this evolvement – its primary task was to discuss, analyze and come up with proposals for how businesses and society should prepare for future MBMI, disruptive BM’s and Business Model Ecosystems (BMES) [1–4, 6, 7, 16]. Sensing BM’s seems to hold some solutions to meet this development. The academic classification of Sensing BM’s and Sensing MBMI have until now been very fragmented defined. The Sensing BM and Sensing MBMI have not been clearly defined, also compared to other types of BM’s and Business Model Innovation (BMI). Several businesses believe they innovate Sensing BM’s (SBM), Operate Industrial 4.0 with advanced sensors – but are challenged when asked to classify SBM and SBMI. The paper addresses – when can a BM be classified as a SBM. In relation to this topic – When can a business be classified as doing SBMI. The aim of the paper is: (1) to add to the development of conceptual framework models and typologies [10–12] for classifying SBM’s and disruptive, radical and incremental SBM’s and SBMIs. (2) to add to the development of MBMI framework and language using advanced sensor and wireless technologies. The preliminary research was supported by a BM and BMI framework [29], combined with advanced sensing technology, enabling researchers to observe and do experiments with SBM’s and SBMI.
关键词： Sensing Business Models,Sensor Technology,Digitalization of Business Models and Business Model Innovation,Sensing Business Model Innovation
更新于2025-09-04 15:30:14
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Highly Accurate and Fully Automatic 3D Head Pose Estimation and Eye Gaze Estimation Using RGB-3D Sensors and 3D Morphable Models
摘要： This work addresses the problem of automatic head pose estimation and its application in 3D gaze estimation using low quality RGB-D sensors without any subject cooperation or manual intervention. The previous works on 3D head pose estimation using RGB-D sensors require either an offline step for supervised learning or 3D head model construction, which may require manual intervention or subject cooperation for complete head model reconstruction. In this paper, we propose a 3D pose estimator based on low quality depth data, which is not limited by any of the aforementioned steps. Instead, the proposed technique relies on modeling the subject’s face in 3D rather than the complete head, which, in turn, relaxes all of the constraints in the previous works. The proposed method is robust, highly accurate and fully automatic. Moreover, it does not need any offline step. Unlike some of the previous works, the method only uses depth data for pose estimation. The experimental results on the Biwi head pose database confirm the efficiency of our algorithm in handling large pose variations and partial occlusion. We also evaluated the performance of our algorithm on IDIAP database for 3D head pose and eye gaze estimation.
关键词： 3D eye gaze estimation,3D head pose estimation,RGB-D sensors,3D morphable models,iterative closest point
更新于2025-09-04 15:30:14
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Modelling dark current and hot pixels in imaging sensors
摘要： A Gaussian mixture model with a structured covariance matrix was used to analyse image data recorded by a digital sensor under darkness to model the effects of temperature and duration of exposure on the expected value and on the variance of the sensor dark current, separately for ordinary and possibly defective pixels. The model accounts for two components of variance within each latent type: random noise in each image and lack of uniformity within the sensor; both components are allowed to depend on experimental conditions. The results seem to indicate that the dependence of the expected value of dark current on duration of exposure and temperature cannot be represented by a simple parametric model. The latent class model detects the presence of at least two types of hot pixels. If we order the latent classes in decreasing order of the class weights, the corresponding expected values and variances increase. The covariance structure that emerges from our analysis has an important implication: the sign and the relative size of pixels deviations from uniformity are invariant to experimental conditions.
关键词： components of variance,dark current,hot pixels,latent class models,dark frames,Gaussian mixtures
更新于2025-09-04 15:30:14
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Forecasting Solar Activity with Computational Intelligence Models
摘要： It is vital to accurately predict solar activity, in order to decrease the plausible damage of electronic equipment in the event of a large high-intensity solar eruption. Recently, we have proposed BELFIS (Brain Emotional Learning-based Fuzzy Inference System) as a tool for the forecasting of chaotic systems. The structure of BELFIS is designed based on the neural structure of fear conditioning. The function of BELFIS is implemented by assigning adaptive networks to the components of the BELFIS structure. This paper especially focuses on performance evaluation of BELFIS as a predictor by forecasting solar cycles 16 to 24. The performance of BELFIS is compared with other computational models used for this purpose, and in particular with adaptive neuro-fuzzy inference system (ANFIS).
关键词： Adaptive Neuro-Fuzzy Inference System,Solar Activity Forecasting,Computational Intelligence Models,Brain Emotional Learning-based Fuzzy Inference System,Solar cycles
更新于2025-09-04 15:30:14
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3D Culture Models of Malignant Mesothelioma Reveal a Powerful Interplay Between Photodynamic Therapy and Kinase Suppression Offering Hope to Reduce Tumor Recurrence
摘要： In this issue, Cramer et al. introduce 3D culture models of metastatic mesothelioma to investigate basic cancer biology and new combination therapies for combating this complex and lethal disease. The results suggest that erlotinib-enhanced photodynamic therapy (PDT) could further improve the efficacy of intraoperative light-activation to mop up residual tumor deposits in the clinic following surgical removal of macroscopic mesothelioma metastases.
关键词： malignant mesothelioma,tumor recurrence,3D culture models,photodynamic therapy,kinase suppression
更新于2025-09-04 15:30:14
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Wiring the depressed brain: optogenetic and chemogenetic circuit interrogation in animal models of depression
摘要： The advent of optogenetics and chemogenetics has revolutionized the study of neural circuit mechanisms of behavioral dysregulation in psychiatric disease. These powerful technologies allow manipulation of specific neurons to determine causal relationships between neuronal activity and behavior. Optogenetic tools have been key to mapping the circuitry underlying depression-like behavior in animal models, clarifying the contribution of the ventral tegmental area, nucleus accumbens, medial prefrontal cortex, ventral hippocampus, and other limbic areas, to stress susceptibility. In comparison, chemogenetics have been relatively underutilized, despite offering unique advantages for probing long-term effects of manipulating neuronal activity. The ongoing development of optogenetic tools to probe in vivo function of ever-more specific circuits, combined with greater integration of chemogenetic tools and recent advances in vivo imaging techniques will continue to advance our understanding of the circuit mechanisms of depression.
关键词： chemogenetics,neural circuits,optogenetics,animal models,depression
更新于2025-09-04 15:30:14