Depth Super-Resolution from Explicit and Implicit High-Frequency Features

We propose a novel multi-stage depth super-resolution network, which progressively reconstructs high-resolution depth maps from explicit and implicit high-frequency features. The former are extracted by an efficient transformer processing both local and global contexts, while the latter are obtained by projecting color images into the frequency domain. Both are combined together with depth features by means of a fusion strategy within a multi-stage and multi-scale framework. Experiments on the main benchmarks, such as NYUv2, Middlebury, DIML and RGBDD, show that our approach outperforms existing methods by a large margin (~20% on NYUv2 and DIML against the contemporary work DADA, with 16x upsampling), establishing a new state-of-the-art in the guided depth super-resolution task

Beyond chemically defined – Characterization of chemically defined cell culture medium for the cultivation of CHO cells

Krattenmacher F. Beyond chemically defined – Characterization of chemically defined cell culture medium for the cultivation of CHO cells. Bielefeld: Universität Bielefeld; 2020.Chemically defined media (CDM) for cell culture are routinely used in industrial processes for recombinant protein production from mammalian expression systems as for example Chinese hamster ovary (CHO) cells. As CDM are nowadays considered as the industry standard the focus has shifted from implementation and improvement of performance to additionally their chemical behavior and the impact on process robustness. Since CDM are highly concentrated aqueous mixtures of versatile chemical compounds one particular problem in this context is the high risk for chemical reactions and instability. Therefore, a major focus of this thesis is the generation of understanding for chemical interactions of CDM compounds and especially the establishment of analytical technologies for the purpose of media characterization. Thus, a mixed mode liquid chromatography tandem mass spectrometry (LC-QqQ-MS) method that is able to simultaneously quantify the majority of media compounds has been developed and validated. This powerful method has been applied to characterize the chemical behavior of feed media under process relevant conditions as preparation and storage. Further on line and off line analytics have been applied to gain insight into CDM chemistry. The application of probes measuring standard parameters have shown the dynamic behavior of chemical key parameters during CDM powder hydration. A Particle probe, such as the focused beam reflectance measurement (FBRM), has been shown to be useful for dissolution behavior investigations of different media recipes or powder compositions. However, it is rather difficult to establish the technology for batch to batch comparison or the monitoring of deviations from the standard preparation conditions. Media preparations with simplified media powders revealed that the compounds ascorbic acid and phosphates cause an apparent drop in dissolved oxygen concentration upon iron compound addition. The combination of the experiments with the newly developed LC QqQ MS method confirmed the comparability of chemical behavior in different media matrixes of most of the CDM compounds but highlighted some differences. Furthermore, measurements with the LC-QqQ-MS showed that the effect of preparation temperature and relevant storage conditions on media stability were negligible. In contrast, measurement of samples over storage time identified unstable compounds. A closer look at the media after storage showed that some formulations formed precipitate during storage and the collection of the solid material on filter membranes revealed their different appearance. Investigations of the material with specialized analytics proved that their identity was heterogeneous. One precipitate that was drawing attention on itself was of silver color and could be shown to consist of Sulphur

Special oils for halal and safe cosmetics

Three types of non conventional oils were extracted, analyzed and tested for toxicity. Date palm kernel oil (DPKO), mango kernel oil (MKO) and Ramputan seed oil (RSO). Oil content for tow cultivars of dates Deglect Noor and Moshkan was 9.67% and 7.30%, respectively. The three varieties of mango were found to contain about 10% oil in average. The red yellow types of Ramputan were found to have 11 and 14% oil, respectively. The phenolic compounds in DPKO, MKO and RSO were 0.98, 0.88 and 0.78 mg/ml Gallic acid equivalent, respectively. Oils were analyzed for their fatty acid composition and they are rich in oleic acid C18:1 and showed the presence of (dodecanoic acid) lauric acid C12:0, which reported to appear some antimicrobial activities. All extracted oils, DPKO, MKO and RSO showed no toxic effect using prime shrimp bioassay. Since these oils are stable, melt at skin temperature, have good lubricity and are great source of essential fatty acids; they could be used as highly moisturizing, cleansing and nourishing oils because of high oleic acid content. They are ideal for use in such halal cosmetics such as Science, Engineering and Technology 75 skin care and massage, hair-care, soap and shampoo products

Batteries and Supercapacitors Aging

Electrochemical energy storage is a key element of systems in a wide range of sectors, such as electro-mobility, portable devices, and renewable energy. The energy storage systems (ESSs) considered here are batteries, supercapacitors, and hybrid components such as lithium-ion capacitors. The durability of ESSs determines the total cost of ownership, the global impacts (lifecycle) on a large portion of these applications and, thus, their viability. Understanding ESS aging is a key to optimizing their design and usability in terms of their intended applications. Knowledge of ESS aging is also essential to improve their dependability (reliability, availability, maintainability, and safety). This Special Issue includes 12 research papers and 1 review article focusing on battery, supercapacitor, and hybrid capacitor aging

Exploiting Spatio-Temporal Coherence for Video Object Detection in Robotics

This paper proposes a method to enhance video object detection for indoor environments in robotics. Concretely, it exploits knowledge about the camera motion between frames to propagate previously detected objects to successive frames. The proposal is rooted in the concepts of planar homography to propose regions of interest where to find objects, and recursive Bayesian filtering to integrate observations over time. The proposal is evaluated on six virtual, indoor environments, accounting for the detection of nine object classes over a total of ∼ 7k frames. Results show that our proposal improves the recall and the F1-score by a factor of 1.41 and 1.27, respectively, as well as it achieves a significant reduction of the object categorization entropy (58.8%) when compared to a two-stage video object detection method used as baseline, at the cost of small time overheads (120 ms) and precision loss (0.92).</p

Mathematically inspired approaches to face recognition in uncontrolled conditions: super resolution and compressive sensing

Face recognition systems under uncontrolled conditions using surveillance cameras is becom-ing essential for establishing the identity of a person at a distance from the camera and providing safety and security against terrorist, attack, robbery and crime. Therefore, the performance of face recognition in low-resolution degraded images with low quality against im-ages with high quality/and of good resolution/size is considered the most challenging tasks and constitutes focus of this thesis. The work in this thesis is designed to further investigate these issues and the following being our main aim: “To investigate face identification from a distance and under uncontrolled conditions by pri-marily addressing the problem of low-resolution images using existing/modified mathemati-cally inspired super resolution schemes that are based on the emerging new paradigm of compressive sensing and non-adaptive dictionaries based super resolution.” We shall firstly investigate and develop the compressive sensing (CS) based sparse represen-tation of a sample image to reconstruct a high-resolution image for face recognition, by tak-ing different approaches to constructing CS-compliant dictionaries such as Gaussian Random Matrix and Toeplitz Circular Random Matrix. In particular, our focus is on constructing CS non-adaptive dictionaries (independent of face image information), which contrasts with ex-isting image-learnt dictionaries, but satisfies some form of the Restricted Isometry Property (RIP) which is sufficient to comply with the CS theorem regarding the recovery of sparsely represented images. We shall demonstrate that the CS dictionary techniques for resolution enhancement tasks are able to develop scalable face recognition schemes under uncontrolled conditions and at a distance. Secondly, we shall clarify the comparisons of the strength of sufficient CS property for the various types of dictionaries and demonstrate that the image-learnt dictionary far from satisfies the RIP for compressive sensing. Thirdly, we propose dic-tionaries based on the high frequency coefficients of the training set and investigate the im-pact of using dictionaries on the space of feature vectors of the low-resolution image for face recognition when applied to the wavelet domain. Finally, we test the performance of the de-veloped schemes on CCTV images with unknown model of degradation, and show that these schemes significantly outperform existing techniques developed for such a challenging task. However, the performance is still not comparable to what could be achieved in controlled en-vironment, and hence we shall identify remaining challenges to be investigated in the future

Orchestration of the neural stem cell fate by NRF2 and TAZ

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Bioquímica. Fecha de lectura: 11-10-2019Neurogenesis is a multiple step process that must be tightly regulated or otherwise results in pathological events. Therefore, a deep characterization of the molecular mechanisms that control the biology of neural stem/progenitor cells (NSPCs) will provide a better understanding of the role of neurogenic niches and new therapeutic strategies for neurodegenerative diseases and brain tumours. In this thesis we have analyzed the regulation of NSCs fate by the transcription factor Nuclear factor (erythroid-derived 2)-like 2 (NRF2), which is considered a master regulator of cellular homeostasis, and the Transcriptional co-activator with PDZ-binding motif (TAZ), a major effector of the Hippo pathway. NRF2 controls the expression of a wide battery of cytoprotective genes that have a tremendous impact on physiological responses such as inflammation, senescence or metabolism. However, its relevance in neurogenesis is just starting to be unveiled. On the other hand, TAZ is a major effector of the Hippo pathway, which plays a key role in tissue homeostasis and organ size control by regulating tissue-specific stem cells. However, the implication of TAZ in neurogenesis has not been analyzed. In this study, we have identified NRF2 as a regulator of hippocampal NSCs self-renewal and differentiation. We show that genetic manipulation of NRF2 results in the modulation of NSPCs differentiation and proliferation capacity. To assess the functional relevance of NRF2 in neurogenesis under pathological conditions, we analyzed the impact of NRF2 deficiency in neurogenesis of the subgranular zone (SGZ) of the hippocampus in a mouse model of Alzheimer´s Disease (AD). We found that NRF2 deficiency results in an accelerated loss of NSCs, loss of synaptic plasticity measured as long term potentiation (LTP) and impaired the execution of cognitive tasks. At the molecular level, we have identified NRF2 enhancer sequences, termed Antioxidant Response Elements (AREs), in the promoter region of the TAZ coding gene. Consequently, we show that genetic and pharmacological manipulation of NRF2 results in the modulation of TAZ gene expression in NSPCs. These findings open a new window to understand the molecular mechanisms underlying NRF2 function in stemness. We have also established a novel role of TAZ as repressor of neuronal differentiation, based on the transcriptional repression of SOX2 and the basic helix-loop-helix (bHLH) factors ASCL1, NEUROG2 and NEUROD1. Data mining of The Cancer Genome Atlas showed a negative correlation between TAZ and the expression of these proneurogenic factors in lower grade gliomas and glioblastomas. We found that TAZ favours glioblastoma CSCs tumorigenic capacity and that genetic modulation of TAZ in these cells inversely correlated with proneurogenic genes expression. Due to the relevance of these proneurogenic factors in the ablation of glioblastoma cancer stem cells (CSCs), this novel TAZ/proneurogenic factors axis may have important implications in the development of this type of brain tumours. The characterization of molecular mechanism governing NSPCs fate provides new insights to harness these cells for brain repair. Overall, this thesis describes a novel role of NRF2 and TAZ in the control of neural stem cell fate, suggesting a new strategy to combat brain pathology