2,936 research outputs found
Quantification of virus syndrome in chili peppers
One of the most important problems to produce chili crops is the presence of diseases caused by pathogen agents, such as viruses, therefore, there is a substantial necessity to better predict the behavior of the diseases of these crops, determining a more precise quantification of the diseaseâs syndrome that allows the investigators to evaluate better practices, from handling to the experimental level and will permit producers to take opportunistic corrective action thereby, reducing production loses and increasing the quality of the crop. This review discussed methods that have been used for the quantification of disease in plants, specifically for chili peppers crops, thereby, suggesting a better alternative for the quantification of the diseaseâ syndromes in regards to this crop. The result of these reflections indicates that most methods used for quantification are based on visual assessments, discarding differences of data between distinctive evaluators. These methods generate subjective results.Key words: Quantification, plant diseases, severity, syndrome, viruses
Use of elicitors as an approach for sustainable agriculture
Plant pathogens are responsible for large declines in agricultural production. Their control is carried out mainly by chemical and frequently proposed biological methods to reduce their environmental impact. On the other hand, plant-pathogen or microbe interactions generate multiple signals within plants activating defense mechanism, some of which can also be induced by elicitors (protective molecules). Elicitor-induced plant signaling serves as a guide to a series of intracellular events that end in activation of transduction cascades and hormonal pathways triggering induced resistance (IR) and consequently activation of plant immunity to environmental stresses. So, it is necessary to understand where and how elicitors act in cellular defense mechanism of crops, to improve protection and management for sustainable crop. Therefore this review focused on main topics that guide induced resistance and therefore activation of plant immune response.Keywords: Elicitors, defense mechanism, Immune response, Induced resistance, MAP
Development of efficient recirculation system for Tilapia (Oreochromis niloticus) culture using low cost materials
In the current experiment, a recirculation system was built using low cost materials that are available locally and its performance was tested. The performance evaluation procedure was carried out in an aquaculture system in greenhouse with sex-reversed male Nile tilapia (Oreochromis niloticus) production in Querétaro State, Mexico. The recirculation system had four sections (sediment collector, gravel and sand filters, biofilter and clarification) in order to eliminate the organic matter produced by the fish excretion material and uneaten food, as well as, the nitrogenous compounds undesirable in the water tanks, such as, total ammonia nitrogen (TAN). The monitored variables include: temperature, dissolved oxygen, pH, visibility, TAN, nitrites and nitrates. The obtained data were compared with previous studies to evaluate the achieved state of the system. This research clearly demonstrated that it is feasible to use the proposed configuration in aquaculture systems in areas where water source is limited. Consequently, the obtained results represent an environmental standpoint for the conservation of water use in the aquaculture industry and also constitute an important contribution to the aquaculture and farmers who receive minimal economic support.Key words: Water recirculation, aquaculture, sustainability, low cost, water use efficiency
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,
CarriĂłn-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 RemiÂżgia Cave, CastelloÂżn (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. ValentĂn Villaverde and Dra. Esther
LĂłpez-Montalvo are also gratefully acknowledged. The
authors acknowledge the research project HAR2014-59873-R
from the Spanish Ministerio de EconomĂa y Competitividad
for providing financial support.Del Hoyo-MelĂ©ndez, JM.; CarriĂłn-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.2013.01.013DĂez-Herrero, A., GutiĂ©rrez-PĂ©rez, I., Lario, J., Cañaveras, J. C., Benavente, D., SĂĄnchez-Moral, S., & Alonso-AzcĂĄrate, 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.20274LĂłpez-Montalvo, E., Villaverde, V., RoldĂĄn, C., Murcia, S., & Badal, E. (2014). An approximation to the study of black pigments in Cova Remigia (CastellĂłn, 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-LĂłpez, 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., LĂłpez-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). DigitalizaciĂłn de cuevas con arte paleolĂtico parietal de Bizkaia. AnĂĄlisis cientĂfico y divulgaciĂłn mediante nuevas tĂ©cnicas de visualizaciĂłn. Virtual Archaeology Review, 9(18), 57. doi:10.4995/var.2018.7579CarriĂłn-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 ARQUEOLĂGICA 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., & SepĂșlveda, 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.2016.07.026LĂłpez-Menchero Bendicho, V. M., Marchante Ortega, Ă., Vincent, M., CĂĄrdenas MartĂn-Buitrago, Ă. J., & Onrubia Pintado, J. (2017). Uso combinado de la fotografĂa digital nocturna y de la fotogrametrĂa en los procesos de documentaciĂłn de petroglifos: el caso de AlcĂĄzar de San Juan (Ciudad Real, España). Virtual Archaeology Review, 8(17), 64. doi:10.4995/var.2017.6820Molada-Tebar, A., Lerma, J. L., & MarquĂ©s-Mateu, Ă. (2017). Camera characterization for improving color archaeological documentation. Color Research & Application, 43(1), 47-57. doi:10.1002/col.22152Del Hoyo-MelĂ©ndez, J. M., Lerma, J. L., LĂłpez-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-MelĂ©ndez, 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 463LĂłpez-Montalvo, E., RoldĂĄn, C., Badal, E., Murcia-MascarĂłs, 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 chaĂźne opĂ©ratoire. PLOS ONE, 12(2), e0172225. doi:10.1371/journal.pone.0172225RoldĂĄn, C., Murcia-MascarĂłs, S., Ferrero, J., Villaverde, V., LĂłpez, 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.1254RoldĂĄn GarcĂa, C., Villaverde Bonilla, V., RĂłdenas MarĂn, I., & Murcia MascarĂłs, S. (2016). A Unique Collection of Palaeolithic Painted Portable Art: Characterization of Red and Yellow Pigments from the ParpallĂł Cave (Spain). PLOS ONE, 11(10), e0163565. doi:10.1371/journal.pone.0163565Ćojewski, T., Thomas, J., GoĆÄ
b, R., KawaĆko, J., & Ćojewska, J. (2011). Note: Light ageing with simultaneous colorimetry via fibre optics reflection spectrometry. Review of Scientific Instruments, 82(7), 076102. doi:10.1063/1.3606645Ruppert, D., Wand, M. P., & Carroll, R. J. (2009). Semiparametric regression during 2003â2007. Electronic Journal of Statistics, 3(0), 1193-1256. doi:10.1214/09-ejs525ISO11664â2:2007(E)/CIE S 014â2/E:2006 ColorimetryâPart 2: Standard Illuminants for Colorimetry.http://cie.co.at/index.php?i_ca_id=484. Accessed October 25 2017.ISO11664â1:2007(E)/CIE S 014â1/E:2006 CIE ColorimetryâPart 1: Standard Colorimetric Observers.http://cie.co.at/index.php?i_ca_id=483. Accessed October 25 2017.Arkivprodukter. The Blue Wool Standards.www.arkivprodukter.no. Accessed November 23 2017.Bacci, M., Cucci, C., Mencaglia, A. A., Mignani, A. G., & Porcinai, S. (2004). Calibration and Use of Photosensitive Materials for Light Monitoring in Museums. Studies in Conservation, 49(2), 85-98. doi:10.1179/sic.2004.49.2.85ISO 12647â2. International Standard for the Production of HalfâTone Colour.2004;2004
Does timing of decisions in a mixed duopoly matter?
We determine the endogenous order of moves in a mixed pricesetting duopoly. In contrast to the existing literature on mixed oligopolies we establish the payo equivalence of the games with an exogenously given order of moves if the most plausible equilibrium is realized in the market. Hence, in this case it does not matter whether one becomes a leader or a follower. We also establish that replacing a private firm by a public firm in the standard Bertrand-Edgeworth game with capacity constraints increases social welfare and that a pure-strategy equilibrium always exists
Spectra of supernovae in the nebular phase
When supernovae enter the nebular phase after a few months, they reveal
spectral fingerprints of their deep interiors, glowing by radioactivity
produced in the explosion. We are given a unique opportunity to see what an
exploded star looks like inside. The line profiles and luminosities encode
information about physical conditions, explosive and hydrostatic
nucleosynthesis, and ejecta morphology, which link to the progenitor properties
and the explosion mechanism. Here, the fundamental properties of spectral
formation of supernovae in the nebular phase are reviewed. The formalism
between ejecta morphology and line profile shapes is derived, including effects
of scattering and absorption. Line luminosity expressions are derived in
various physical limits, with examples of applications from the literature. The
physical processes at work in the supernova ejecta, including gamma-ray
deposition, non-thermal electron degradation, ionization and excitation, and
radiative transfer are described and linked to the computation and application
of advanced spectral models. Some of the results derived so far from
nebular-phase supernova analysis are discussed.Comment: Book chapter for 'Handbook of Supernovae,' edited by Alsabti and
Murdin, Springer. 51 pages, 14 figure
Clinical impact of Doppler reference charts on management of smallâforâgestationalâage fetuses: need for standardization
Objective
To assess clinical variability in the management of smallâforâgestationalâage (SGA) fetuses according to different published Doppler reference charts for umbilical artery (UA) and fetal middle cerebral artery (MCA) Doppler indices and cerebroplacental ratio (CPR).
Methods
We performed a systematic search of MEDLINE, EMBASE, CINAHL and the Web of Science databases from 1954 to 2018 for studies with the sole aim of creating fetal Doppler reference values for UA, MCA and CPR. The top cited articles for each Doppler parameter were included. Variability in Doppler values at the following clinically relevant cutâoffs was assessed: UAâpulsatility index (PI)â>â95th percentile; MCAâPI <â5th percentile; and CPR <â5th percentile. Variability was calculated for each week of gestation and expressed as the percentage difference between the highest and lowest Doppler value at the clinically relevant cutâoffs. Simulation analysis was performed in a cohort of SGA fetuses (n â=â617) to evaluate the impact of this variability on clinical management.
Results
From a total of 40 studies that met the inclusion criteria, 19 were analyzed (13 for UAâPI, 10 for MCAâPI and five for CPR). Wide discrepancies in reported Doppler reference values at clinically relevant cutâoffs were found. MCAâPI showed the greatest variability, with differences of up to 51% in the 5th percentile value at term. Variability in the 95th percentile of UAâPI and the 5th percentile of CPR at each gestational week ranged from 21% to 41% and 15% to 33%, respectively. As expected, on simulation analysis, these differences in Doppler cutâoff values were associated with significant variation in the clinical management of SGA fetuses, despite using the same protocol.
Conclusions
The choice of Doppler reference chart can result in significant variation in the clinical management of SGA fetuses, which may lead to suboptimal outcomes and inaccurate research conclusions. Therefore, an attempt to standardize fetal Doppler reference ranges is needed
FASTKIT: A Mobile Cable-Driven Parallel Robot for Logistics
International audienceThe subject of this paper is about the design, modeling, control and performance evaluation of a low cost and versatile robotic solution for logistics. The robot under study, named FASTKIT, is obtained from a combination of mobile robots and a Cable-Driven Parallel Robot (CDPR). FASTKIT addresses an industrial need for fast picking and kitting operations in existing storage facilities while being easy to install, keeping existing infrastructures and covering large areas. The FASTKIT prototype consists of two mobile bases that carry the exit points of the CDPR. The system can navigate autonomously to the area of interest. Once the desired position is attained, the system deploys the CDPR in such a way that its workspace corresponds to the current task specification. The system calculates the required mobile base position from the desired workspace and ensures the controllability of the platform during the deployment. Once the system is successfully deployed, the set of stabilizers are used to ensure the prototype structural stability. Then the prototype gripper is moved accurately by the CDPR at high velocity over a large area by controlling the cable tension
Challenges of Profile Likelihood Evaluation in Multi-Dimensional SUSY Scans
Statistical inference of the fundamental parameters of supersymmetric
theories is a challenging and active endeavor. Several sophisticated algorithms
have been employed to this end. While Markov-Chain Monte Carlo (MCMC) and
nested sampling techniques are geared towards Bayesian inference, they have
also been used to estimate frequentist confidence intervals based on the
profile likelihood ratio. We investigate the performance and appropriate
configuration of MultiNest, a nested sampling based algorithm, when used for
profile likelihood-based analyses both on toy models and on the parameter space
of the Constrained MSSM. We find that while the standard configuration is
appropriate for an accurate reconstruction of the Bayesian posterior, the
profile likelihood is poorly approximated. We identify a more appropriate
MultiNest configuration for profile likelihood analyses, which gives an
excellent exploration of the profile likelihood (albeit at a larger
computational cost), including the identification of the global maximum
likelihood value. We conclude that with the appropriate configuration MultiNest
is a suitable tool for profile likelihood studies, indicating previous claims
to the contrary are not well founded.Comment: 21 pages, 9 figures, 1 table; minor changes following referee report.
Matches version accepted by JHE
ESR1 gene promoter region methylation in free circulating DNA and its correlation with estrogen receptor protein expression in tumor tissue in breast cancer patients
[Background]
Tumor expression of estrogen receptor (ER) is an important marker of prognosis, and is predictive of response to endocrine therapy in breast cancer. Several studies have observed that epigenetic events, such methylation of cytosines and deacetylation of histones, are involved in the complex mechanisms that regulate promoter transcription. However, the exact interplay of these factors in transcription activity is not well understood. In this study, we explored the relationship between ER expression status in tumor tissue samples and the methylation of the 5âČ CpG promoter region of the estrogen receptor gene (ESR1) isolated from free circulating DNA (fcDNA) in plasma samples from breast cancer patients.
[Methods]
Patients (nâ=â110) with non-metastatic breast cancer had analyses performed of ER expression (luminal phenotype in tumor tissue, by immunohistochemistry method), and the ESR1-DNA methylation status (fcDNA in plasma, by quantitative methylation specific PCR technique).
[Results]
Our results showed a significant association between presence of methylated ESR1 in patients with breast cancer and ER negative status in the tumor tissue (pâ=â0.0179). There was a trend towards a higher probability of ESR1-methylation in those phenotypes with poor prognosis i.e. 80% of triple negative patients, 60% of HER2 patients, compared to 28% and 5.9% of patients with better prognosis such as luminal A and luminal B, respectively.
[Conclusion]
Silencing, by methylation, of the promoter region of the ESR1 affects the expression of the estrogen receptor protein in tumors of breast cancer patients; high methylation of ESR1-DNA is associated with estrogen receptor negative status which, in turn, may be implicated in the patientâs resistance to hormonal treatment in breast cancer. As such, epigenetic markers in plasma may be of interest as new targets for anticancer therapy, especially with respect to endocrine treatment.The study was funded, in part, by a grant from the Ministerio de EducaciĂłn y Ciencia (CICYT: SAF 2004â00889)
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