Dominant Color Extraction with K-Means for Camera Characterization in Cultural Heritage Documentation

The camera characterization procedure has been recognized as a convenient methodology to correct color recordings in cultural heritage documentation and preservation tasks. Instead of using a whole color checker as a training sample set, in this paper, we introduce a novel framework named the Patch Adaptive Selection with K-Means (P-ASK) to extract a subset of dominant colors from a digital image and automatically identify their corresponding chips in the color chart used as characterizing colorimetric reference. We tested the methodology on a set of rock art painting images captured with a number of digital cameras. The characterization approach based on the P-ASK framework allows the reduction of the training sample size and a better color adjustment to the chromatic range of the input scene. In addition, the computing time required for model training is less than in the regular approach with all color chips, and obtained average color differences ΔE∗ab lower than two CIELAB units. Furthermore, the graphic and numeric results obtained for the characterized images are encouraging and confirms that the P-ASK framework based on the K-means algorithm is suitable for automatic patch selection for camera characterization purposes

Voluntary control of wearable robotic exoskeletons by patients with paresis via neuromechanical modeling.

BACKGROUND: Research efforts in neurorehabilitation technologies have been directed towards creating robotic exoskeletons to restore motor function in impaired individuals. However, despite advances in mechatronics and bioelectrical signal processing, current robotic exoskeletons have had only modest clinical impact. A major limitation is the inability to enable exoskeleton voluntary control in neurologically impaired individuals. This hinders the possibility of optimally inducing the activity-driven neuroplastic changes that are required for recovery. METHODS: We have developed a patient-specific computational model of the human musculoskeletal system controlled via neural surrogates, i.e., electromyography-derived neural activations to muscles. The electromyography-driven musculoskeletal model was synthesized into a human-machine interface (HMI) that enabled poststroke and incomplete spinal cord injury patients to voluntarily control multiple joints in a multifunctional robotic exoskeleton in real time. RESULTS: We demonstrated patients' control accuracy across a wide range of lower-extremity motor tasks. Remarkably, an increased level of exoskeleton assistance always resulted in a reduction in both amplitude and variability in muscle activations as well as in the mechanical moments required to perform a motor task. Since small discrepancies in onset time between human limb movement and that of the parallel exoskeleton would potentially increase human neuromuscular effort, these results demonstrate that the developed HMI precisely synchronizes the device actuation with residual voluntary muscle contraction capacity in neurologically impaired patients. CONCLUSIONS: Continuous voluntary control of robotic exoskeletons (i.e. event-free and task-independent) has never been demonstrated before in populations with paretic and spastic-like muscle activity, such as those investigated in this study. Our proposed methodology may open new avenues for harnessing residual neuromuscular function in neurologically impaired individuals via symbiotic wearable robots

Lightfastness assessment of Levantine rock art by means of microfading spectrometry

This is the peer reviewed version of the following article: del Hoyo-Meléndez JM, Carrión-Ruiz B, Riutort-Mayol G, Lerma JL. Lightfastness assessment of Levantine rock art by means of microfading spectrometry. Color Res Appl. 2019;44:547 555, which has been published in final form at https://doi.org/10.1002/col.22372. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] The documentation of archeological sites requires the adoption of non-destructive techniques to safeguard the unique legacy coming from prehistoric periods. This article tackles the assessment of lightfastness properties on a rock art site to deter- mine the behavior of motif's color deterioration over time in Remi¿gia Cave, Castello¿n (Spain), which is considered part of a UNESCO World Heritage Site. The measurements were performed using a microfade testing device to analyze the spectral characteristics and the aging properties of the colorant system and various substrates on site. Two scenarios have been identified depending on whether the lightness (L*) parameter of the rocky substrate changes or not in relation with the painted motifs. If the substrate remains stable without any change, red motifs con- taining iron oxide pigments will become more visible. If the substrate becomes lighter, the pigments will experience similar changes. Therefore, the contrast between paintings and support will be considerably enhanced.The authors also would like to thank the Generalitat Valenciana for providing access to the site during the measurement campaigns. Fruitful comments from the Spanish archeologists Prof. Valentín Villaverde and Dra. Esther López-Montalvo are also gratefully acknowledged. The authors acknowledge the research project HAR2014-59873-R from the Spanish Ministerio de Economía y Competitividad for providing financial support.Del Hoyo-Meléndez, JM.; Carrión-Ruiz, B.; Riutort-Mayol, G.; Lerma, JL. (2019). Lightfastness assessment of Levantine rock art by means of microfading spectrometry. Color Research & Application. 44(4):547-555. https://doi.org/10.1002/col.22372S547555444Vileikis, O., Cesaro, G., Santana Quintero, M., van Balen, K., Paolini, A., & Vafadari, A. (2012). Documentation in World Heritage conservation. Journal of Cultural Heritage Management and Sustainable Development, 2(2), 130-152. doi:10.1108/20441261211273635Management Planning for Archaelogical Sites 2002 The Getty Conservation Institute Los Angeles G Palumbo Threats and challenges to the archaeological heritage in the Mediterranean 3 12ICOMOS. ICOMOS World Report 2000 on Monuments and Sites in Danger; 2000.https://www.icomos.org/risk/world_report/2000/risk2000.htm. Accessed October 25 2017.Giesen, M. J., Ung, A., Warke, P. A., Christgen, B., Mazel, A. D., & Graham, D. W. (2014). Condition assessment and preservation of open-air rock art panels during environmental change. Journal of Cultural Heritage, 15(1), 49-56. doi:10.1016/j.culher.2013.01.013Díez-Herrero, A., Gutiérrez-Pérez, I., Lario, J., Cañaveras, J. C., Benavente, D., Sánchez-Moral, S., & Alonso-Azcárate, J. (2009). Analysis of potential direct insolation as a degradation factor of cave paintings in Villar del Humo, Cuenca, Central Spain. Geoarchaeology, 24(4), 450-465. doi:10.1002/gea.20274López-Montalvo, E., Villaverde, V., Roldán, C., Murcia, S., & Badal, E. (2014). An approximation to the study of black pigments in Cova Remigia (Castellón, Spain). Technical and cultural assessments of the use of carbon-based black pigments in Spanish Levantine Rock Art. Journal of Archaeological Science, 52, 535-545. doi:10.1016/j.jas.2014.09.017Hernanz, A., Ruiz-López, J. F., Gavira-Vallejo, J. M., Martin, S., & Gavrilenko, E. (2010). Raman microscopy of prehistoric rock paintings from the Hoz de Vicente, Minglanilla, Cuenca, Spain. Journal of Raman Spectroscopy, 41(11), 1394-1399. doi:10.1002/jrs.2582Domingo, I., Villaverde, V., López-Montalvo, E., Lerma, J. L., & Cabrelles, M. (2013). Latest developments in rock art recording: towards an integral documentation of Levantine rock art sites combining 2D and 3D recording techniques. Journal of Archaeological Science, 40(4), 1879-1889. doi:10.1016/j.jas.2012.11.024Iturbe, A., Cachero, R., Cañal, D., & Martos, A. (2018). Digitalización de cuevas con arte paleolítico parietal de Bizkaia. Análisis científico y divulgación mediante nuevas técnicas de visualización. Virtual Archaeology Review, 9(18), 57. doi:10.4995/var.2018.7579Carrión-Ruiz, B., Blanco-Pons, S., & Lerma, J. L. (2016). DIGITAL IMAGE ANALYSIS OF THE VISIBLE REGION THROUGH SIMULATION OF ROCK ART PAINTINGS. Proceedings of the ARQUEOLÓGICA 2.0 8th International Congress on Archaeology, Computer Graphics, Cultural Heritage and Innovation. doi:10.4995/arqueologica8.2016.3560Fredlund, G., & Sundstrom, L. (2007). Digital infra-red photography for recording painted rock art. Antiquity, 81(313), 733-742. doi:10.1017/s0003598x00095697Cerrillo-Cuenca, E., & Sepúlveda, M. (2015). An assessment of methods for the digital enhancement of rock paintings: the rock art from the precordillera of Arica (Chile) as a case study. Journal of Archaeological Science, 55, 197-208. doi:10.1016/j.jas.2015.01.006Robert, E., Petrognani, S., & Lesvignes, E. (2016). Applications of digital photography in the study of Paleolithic cave art. Journal of Archaeological Science: Reports, 10, 847-858. doi:10.1016/j.jasrep.2016.07.026López-Menchero Bendicho, V. M., Marchante Ortega, Á., Vincent, M., Cárdenas Martín-Buitrago, Á. J., & Onrubia Pintado, J. (2017). Uso combinado de la fotografía digital nocturna y de la fotogrametría en los procesos de documentación de petroglifos: el caso de Alcázar de San Juan (Ciudad Real, España). Virtual Archaeology Review, 8(17), 64. doi:10.4995/var.2017.6820Molada-Tebar, A., Lerma, J. L., & Marqués-Mateu, Á. (2017). Camera characterization for improving color archaeological documentation. Color Research & Application, 43(1), 47-57. doi:10.1002/col.22152Del Hoyo-Meléndez, J. M., Lerma, J. L., López-Montalvo, E., & Villaverde, V. (2015). Documenting the light sensitivity of Spanish Levantine rock art paintings. ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences, II-5/W3, 53-59. doi:10.5194/isprsannals-ii-5-w3-53-2015Whitmore, P. M., Bailie, C., & Connors, S. A. (2000). Micro-fading tests to predict the result of exhibition: progress and prospects. Studies in Conservation, 45(sup1), 200-205. doi:10.1179/sic.2000.45.supplement-1.200Whitmore, P. M., Pan, X., & Bailie, C. (1999). Predicting the Fading of Objects: Identification of Fugitive Colorants through Direct Nondestructive Lightfastness Measurements. Journal of the American Institute for Conservation, 38(3), 395. doi:10.2307/3179999Ford, B. (2011). Non-destructive microfade testing at the National Museum of Australia. AICCM Bulletin, 32(1), 54-64. doi:10.1179/bac.2011.32.1.008Del Hoyo-Meléndez, J. M., & Mecklenburg, M. F. (2010). A survey on the light-fastness properties of organic-based Alaska Native artifacts. Journal of Cultural Heritage, 11(4), 493-499. doi:10.1016/j.culher.2010.01.004Conservation of Ancient Sites on the Silk Road 2010 The Getty Conservation Institute The Getty. Los Angeles JR Druzik Evaluating the light sensitivity of paints in selected wall paintings at the Mogao Grottoes: caves 217 98 and 85 457 463López-Montalvo, E., Roldán, C., Badal, E., Murcia-Mascarós, S., & Villaverde, V. (2017). Identification of plant cells in black pigments of prehistoric Spanish Levantine rock art by means of a multi-analytical approach. A new method for social identity materialization using chaîne opératoire. PLOS ONE, 12(2), e0172225. doi:10.1371/journal.pone.0172225Roldán, C., Murcia-Mascarós, S., Ferrero, J., Villaverde, V., López, E., Domingo, I., … Guillem, P. M. (2010). Application of field portable EDXRF spectrometry to analysis of pigments of Levantine rock art. X-Ray Spectrometry, 39(3), 243-250. doi:10.1002/xrs.1254Roldán García, C., Villaverde Bonilla, V., Ródenas Marín, I., & Murcia Mascarós, S. (2016). A Unique Collection of Palaeolithic Painted Portable Art: Characterization of Red and Yellow Pigments from the Parpalló Cave (Spain). PLOS ONE, 11(10), e0163565. doi:10.1371/journal.pone.0163565Łojewski, T., Thomas, J., Gołąb, R., Kawałko, J., & Łojewska, J. (2011). Note: Light ageing with simultaneous colorimetry via fibre optics reflection spectrometry. 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Frontier in three-dimensional cave reconstruction—3D meshing versus textured rendering

Underground caves and their specific structures are important for geomorphological studies. This paper investigates the capabilities of a new modelling approach advanced for true-to-life three-dimensional (3D) reconstruction of cave with full resolution scan relative to 3D meshing. The cave was surveyed using terrestrial laser scanner (TLS) to acquire high resolution scans. The data was processed to generate a 3D-mesh model and textured 3D model using sub-sampled points and full resolution scan respectively. Based on both point and solid surface representation, comparative analysis of the strengths and weaknesses of the two approaches were examined in terms of data processing efficiency, visualization, interactivity and geomorphological feature representation and identification. The result shows that full scan point representation offers advantage for dynamic visualization over the decimated xyz point data because of high density of points and availability of other surface information like point normal, intensity and height which can be visualized in colour scale. For the reconstructed surface, mesh model is better with respect to interactivity and morphometric but 3D rendering shows superiority in visual reality and identification of micro detail of features with high precision. Complementary use of the two will provide better understanding of the cave, its development and processes

Cellular Basis for Response Diversity in the Olfactory Periphery

An emerging idea in olfaction is that temporal coding of odor specificity can be intrinsic to the primary olfactory receptor neurons (ORNs). As a first step towards understanding whether lobster ORNs are capable of generating odor-specific temporal activity and what mechanisms underlie any such heterogeneity in discharge pattern, we characterized different patterns of activity in lobster ORNs individually and ensemble using patch-clamp recording and calcium imaging. We demonstrate that lobster ORNs show tonic excitation, tonic inhibition, phaso-tonic excitation, and bursting, and that these patterns are faithfully reflected in the calcium signal. We then demonstrate that the various dynamic patterns of response are inherent in the cells, and that this inherent heterogeneity is largely determined by heterogeneity in the underlying intrinsic conductances

Effective Rheology of Bubbles Moving in a Capillary Tube

We calculate the average volumetric flux versus pressure drop of bubbles moving in a single capillary tube with varying diameter, finding a square-root relation from mapping the flow equations onto that of a driven overdamped pendulum. The calculation is based on a derivation of the equation of motion of a bubble train from considering the capillary forces and the entropy production associated with the viscous flow. We also calculate the configurational probability of the positions of the bubbles.Comment: 4 pages, 1 figur

Imipenem resistance of Pseudomonas in pneumonia: a systematic literature review

<p>Abstract</p> <p>Background</p> <p>Pneumonia, and particularly nosocomial (NP) and ventilator-associated pneumonias (VAP), results in high morbidity and costs. NPs in particular are likely to be caused by <it>Pseudomonas aeruginosa </it>(PA), ~20% of which in observational studies are resistant to imipenem. We sought to identify the burden of PA imipenem resistance in pneumonia.</p> <p>Methods</p> <p>We conducted a systematic literature review of randomized controlled trials (RCT) of imipenem treatment for pneumonia published in English between 1993 and 2008. We extracted study, population and treatment characteristics, and proportions caused by PA. Endpoints of interest were: PA resistance to initial antimicrobial treatment, clinical success, microbiologic eradication and on-treatment emergence of resistance of PA.</p> <p>Results</p> <p>Of the 46 studies identified, 20 (N = 4,310) included patients with pneumonia (imipenem 1,667, PA 251; comparator 1,661, PA 270). Seven were double blind, and 7 included US data. Comparator arms included a β-lactam (17, [penicillin 6, carbapenem 4, cephalosporin 7, monobactam 1]), aminoglycoside 2, vancomycin 1, and a fluoroquinolone 5; 5 employed double coverage. Thirteen focused exclusively on pneumonia and 7 included pneumonia and other diagnoses. Initial resistance was present in 14.6% (range 4.2-24.0%) of PA isolates in imipenem and 2.5% (range 0.0-7.4%) in comparator groups. Pooled clinical success rates for PA were 45.2% (range 0.0-72.0%) for imipenem and 74.9% (range 0.0-100.0%) for comparator regimens. Microbiologic eradication was achieved in 47.6% (range 0.0%-100.0%) of isolates in the imipenem and 52.8% (range 0.0%-100.0%) in the comparator groups. Resistance emerged in 38.7% (range 5.6-77.8%) PA isolates in imipenem and 21.9% (range 4.8-56.5%) in comparator groups.</p> <p>Conclusions</p> <p>In the 15 years of RCTs of imipenem for pneumonia, PA imipenem resistance rates are high, and PA clinical success and microbiologic eradication rates are directionally lower for imipenem than for comparators. Conversely, initial and treatment-emergent resistance is more likely with the imipenem than the comparator regimens.</p

Towards an optimal sampling strategy for assessing genetic variation within and among white clover (Trifolium repens L.) cultivars using AFLP

Cost reduction in plant breeding and conservation programs depends largely on correctly defining the minimal sample size required for the trustworthy assessment of intra- and inter-cultivar genetic variation. White clover, an important pasture legume, was chosen for studying this aspect. In clonal plants, such as the aforementioned, an appropriate sampling scheme eliminates the redundant analysis of identical genotypes. The aim was to define an optimal sampling strategy, i.e., the minimum sample size and appropriate sampling scheme for white clover cultivars, by using AFLP data (283 loci) from three popular types. A grid-based sampling scheme, with an interplant distance of at least 40 cm, was sufficient to avoid any excess in replicates. Simulations revealed that the number of samples substantially influenced genetic diversity parameters. When using less than 15 per cultivar, the expected heterozygosity (He) and Shannon diversity index (I) were greatly underestimated, whereas with 20, more than 95% of total intra-cultivar genetic variation was covered. Based on AMOVA, a 20-cultivar sample was apparently sufficient to accurately quantify individual genetic structuring. The recommended sampling strategy facilitates the efficient characterization of diversity in white clover, for both conservation and exploitation

Apoptosis induction in Jurkat cells and sCD95 levels in women's sera are related with the risk of developing cervical cancer

<p>Abstract</p> <p>Background</p> <p>Currently, there is clear evidence that apoptosis plays an important role in the development and progression of tumors. One of the best characterized apoptosis triggering systems is the CD95/Fas/APO-1 pathway; previous reports have demonstrated high levels of soluble CD95 (sCD95) in serum of patients with some types of cancer. Cervical cancer is the second most common cancer among women worldwide. As a first step in an attempt to design a minimally invasive test to predict the risk of developing cervical cancer in patients with precancerous lesions, we used a simple assay based on the capacity of human serum to induce apoptosis in Jurkat cells. We evaluated the relationship between sCD95 levels and the ability to induce apoptosis in Jurkat cells in cervical cancer patients and controls.</p> <p>Methods</p> <p>Jurkat cells were exposed to serum from 63 women (20 healthy volunteers, 21 with cervical intraepithelial neoplasia grade I [CIN 1] and 22 with cervical-uterine carcinoma). The apoptotic rate was measured by flow cytometry using Annexin-V-Fluos and Propidium Iodide as markers. Serum levels of sCD95 and soluble CD95 ligand (sCD95L) were measured by ELISA kits.</p> <p>Results</p> <p>We found that serum from almost all healthy women induced apoptosis in Jurkat cells, while only fifty percent of the sera from women with CIN 1 induced cell death in Jurkat cells. Interestingly, only one serum sample from a patient with cervical-uterine cancer was able to induce apoptosis, the rest of the sera protected Jurkat cells from this killing. We were able to demonstrate that elimination of Jurkat cells was mediated by the CD95/Fas/Apo-1 apoptotic pathway. Furthermore, the serum levels of sCD95 measured by ELISA were significantly higher in women with cervical cancer.</p> <p>Conclusion</p> <p>Our results demonstrate that there is a strong correlation between low levels of sCD95 in serum of normal women and higher apoptosis induction in Jurkat cells. We suggest that an analysis of the apoptotic rate induced by serum in Jurkat cells and the levels of sCD95 in serum could be helpful during the prognosis and treatment of women detected with precancerous lesions or cervical cancer.</p

Increased Anxiety-Like Behavior and Enhanced Synaptic Efficacy in the Amygdala of GluR5 Knockout Mice

GABAergic transmission in the amygdala modulates the expression of anxiety. Understanding the interplay between GABAergic transmission and excitatory circuits in the amygdala is, therefore, critical for understanding the neurobiological basis of anxiety. Here, we used a multi-disciplinary approach to demonstrate that GluR5-containing kainate receptors regulate local inhibitory circuits, modulate the excitatory transmission from the basolateral amygdala to the central amygdala, and control behavioral anxiety. Genetic deletion of GluR5 or local injection of a GluR5 antagonist into the basolateral amygdala increases anxiety-like behavior. Activation of GluR5 selectively depolarized inhibitory neurons, thereby increasing GABA release and contributing to tonic GABA current in the basolateral amygdala. The enhanced GABAergic transmission leads to reduced excitatory inputs in the central amygdala. Our results suggest that GluR5 is a key regulator of inhibitory circuits in the amygdala and highlight the potential use of GluR5-specific drugs in the treatment of pathological anxiety