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Characterization of Gromov Hyperbolic Short Graphs

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Acta Mathematica Sinica,English Series 2014年第2期30卷 197-212页

作者： José manuel rodriguez Departamento de Matemticas Universidad Carlos III de MadridAvenida de la Universidad 30

To decide when a graph is Gromov hyperbolic is,in general,a very hard *** this paper,we solve this problem for the set of short graphs（in an informal way,a graph G is r-short if the shortcuts in the cycles of G have length less than r）：an r-short graph G is hyperbolic if and only if S9r（G）is finite,where SR（G）：=sup{L（C）：C is an R-isometric cycle in G}and we say that a cycle C is R-isometric if dC（x,y）≤dG（x,y）＋R for every x,y∈C.

关键词： Short graph Gromov hyperbolicity Gromov hyperbolic graph infinite graphs geodesics

Open avenues for carotenoid biofortification of plant tissues

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Plant Communications 2023年第1期4卷 228-237页

作者： Luca Morelli manuel rodriguez-Concepcion Institute for Plant Molecular and Cell Biology(IBMCP) CSIC-Universitat Polite`cnica de Vale`ncia46022 ValenciaSpain Department of Biology&CESAM&ECOMARE Universidade de Aveiro3810-193 AveiroPortugal

Plant carotenoids are plastidial isoprenoids that function as photoprotectants,pigments,and precursors of apocarotenoids such as the hormones abscisic acid and *** do not produce carotenoids but need to obtain them from their diet as precursors of retinoids,including vitamin *** also provide numerous other health *** attempts to improve the carotenoid profile of different crops have been carried out by manipulating carotenoid biosynthesis,degradation,and/or ***,we will focus on open questions and emerging subjects related to the use of biotechnology for carotenoid *** impressive achievements,new efforts should be directed to extend the use of genome-editing technologies to overcome regulatory constraints and improve consumer acceptance of the carotenoid-enriched *** challenge is to prevent off-target effects like those resulting from altered hormone levels and metabolic *** on biofortification of green tissues should also look for new ways to deal with the negative impact that altered carotenoid contents may have on *** a carotenoid-enriched product has been obtained,additional effort should be devoted to confirming that carotenoid intake from the engineered food is also *** involves ensuring post-harvest stability and assessing bioaccessibility of the biofortified product to confirm that release of carotenoids from the food matrix has not been negatively *** addressing these challenges will ensure new milestones in carotenoid biotechnology and biofortification.

关键词： biofortification biotechnology carotenoids plastidial isoprenoids vitamin A

Factors affecting the spatial distribution and breeding habitat of an insular cliff-nesting raptor community

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Current Zoology 2018年第2期64卷 173-181页

作者： Beneharo rodriguez Airam rodriguez Felipe SIVERIO manuel SIVERIO Canary Islands' Ornithology and Natural History Group (GOHNIC) La Malecita s/n 38480 Buenavista del NorteTenerife Canary Islands Spain Department of Evolutionary Ecology Estacion Biologica de DoSana (CSIC)Avda. Americo Vespucio s/n Seville 41092 Spain

The specific spatial distribution and habitat association--strongly influenced by environmental fac- tors or competitive interactions--are major issues in ecology and conservation. We located and georeferenced nesting sites of five cliff-nesting raptors （Egyptian vulture Neophron percnopterus [a locally extinct species], common buzzard Buteo buteo, osprey Pandion haliaetus, common kes- trel Falco tinnunculus, Barbary falcon Falco peregrinus pelegrinoides）, and common raven Corvus corax on one of the most biodiverse hotspot within the Canary Islands （Teno, Tenerife）. We used generalized linear models to evaluate the factors affecting abundance, richness, and intra- and interspecific interactions. Raptor abundance increased with slope, shrub-covered area, and habitat diversity, and decreased with altitude, and forested and grassed areas. Richness increased with slope and decreased with altitude. Threatened species （osprey, Barbary falcon, and raven） occu- pied cliffs farther away from houses and roads, and more rugged areas than the non-threatened species. The models suggested that the probability of cliff occupation by buzzards, falcons, and rav- ens depended only on inter-specific interactions. Buzzard occupation increased with the distance to the nearest raven and kestrel nests, whereas falcons and ravens seek proximity to each other. Teno holds between 75% and 100% of the insular breeding populations of the most endangered species （osprey and raven）, indicating the high conservation value of this area. Our study suggests that the preservation of rugged terrains and areas of low human pressure are key factors for raptor conservation and provide basic knowledge on the community structure and habitat associations to develop appropriated management actions for these fragile island populations.

关键词： Canary Islands competitive interactions human disturbances habitat threatened species.

Plant geranylgeranyl diphosphate synthases: every (gene) family has a story

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aBIOTECH 2021年第3期2卷 289-298页

作者： M.Victoria Barja manuel rodriguez-Concepcion Centre for Research in Agricultural Genomics(CRAG)CSIC-IRTA-UAB-UB Campus UAB Bellaterra08193 Barce-lonaSpain Institute for Plant Molecular and Cell Biology(BMCP) CSIC-Universitat Politecnica de Valencia46022 ValenciaSpain

Plant isoprenoids(also known as terpenes or terpenoids)are a wide family of primary and secondary metabolites with multiple *** particular,most photosynthesis-related isoprenoids(including carotenoids and chlorophylls)as well as diterpenes and polyterpenes derive from geranylgeranyl diphosphate(GGPP)produced by GGPP synthase(GGPPS)enzymes in several cell *** genomes typically harbor multiple copies of differentially expressed genes encoding GGPPS-like *** sequence comparisons allow to identify potential GGPPS candidates,experimental evidence is required to ascertain their enzymatic activity and biologi cal ***,functional analyses of the full set of potential GGPPS paralogs are only available for a handful of plant *** we review our current knowledge on the GGPPS families of the model plant Arabidopsis thaliana and the crop species rice(0ryza sativa),pepper(Capsicum annuum)and tomato(Solanum lycopersicum).The results indicate that a major determinant of the biological role of particular GGPPS paralogs is the expression profile of the corresponding genes even though specific interactions with other proteins(including GGPP-consuming enzymes)might also contribute to *** some species,however,a single GGPPS isoforms appears to be responsible for the production of most if not all GGPP required for cell *** the mechanisms regulating GGPPS activity in particular cell compartments,tissues,organs and plant species will be very useful for future metabolic engineering approaches aimed to manipulate the accumulation of particular GGPP-derived products of interest without negatively impacting the levels of other isoprenoids required to sustain essential cell functions.

关键词： Geranylgeranyl diphosphate GGPP GGPP synthase Isoprenoid Isoprenyl transferase

Wavelet-based deconvolution of ultrasonic signals in nondestructive evaluation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1748-1756页

作者： HERRERA Roberto Henry OROZCO Rubén rodriguez manuel Department of Informatics University of Cienfuegos Cienfuegos 59430 Cuba CEETI Central University of Las Villas Santa Clara 54830 Cuba Department of Physics Central University of Las Villas Santa Clara 54830 Cuba

In this paper, the inverse problem of reconstructing reflectivity function of a medium is examined within a blind deconvolution framework. The ultrasound pulse is estimated using higher-order statistics, and Wiener filter is used to obtain the ultrasonic reflectivity function through wavelet-based models. A new approach to the parameter estimation of the inverse filtering step is proposed in the nondestructive evaluation field, which is based on the theory of Fourier-Wavelet regularized deconvolution (ForWaRD). This new approach can be viewed as a solution to the open problem of adaptation of the ForWaRD framework to perform the convolution kernel estimation and deconvolution interdependently. The results indicate stable solutions of the esti- mated pulse and an improvement in the radio-frequency (RF) signal taking into account its signal-to-noise ratio (SNR) and axial resolution. Simulations and experiments showed that the proposed approach can provide robust and optimal estimates of the reflectivity function.

关键词： Blind deconvolution Ultrasonic signals processing Wavelet regularization

New Insights into Plant Isoprenoid Metabolism

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Molecular Plant 2012年第5期5卷 964-967页

作者： Pablo Pulido Catalina Perello manuel rodriguez-Concepcion Department of Molecular Genetics Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB Campus UAB Bellaterra 08193 BarcelonaSpain

Isoprenoids are a hugely diverse family of compounds derived from the C5 precursors isopentenyl diphosphate （IPP） and dimethylallyl diphosphate （DMAPP）. Although all free-living organisms synthesize isoprenoids, they are particularly abun- dant and diverse in plants, with tens of thousands structures known to date. The highest variety of plant isoprenoids are specialized （secondary） metabolites that participate in the interaction of plants with their environment. These include pigments, volatiles, and defense compounds, some of which have applications in industry and agriculture.

关键词： Metabolism Insight Plant

Treatment, residual chlorine and season as factors affecting variability of trihalomethanes in small drinking water systems

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Frontiers of Environmental Science & Engineering 2015年第1期9卷 171-179页

作者： Roberta DYCK Genevieve COOL manuel rodriguez Rehan SADIQ School of Engineering University of British Columbia Okanagan Kelowna V1V 1V7 Canada Ecole superieure d'amenagement du territoire Universite Laval Quebec G1V 0A6 Canada

Seasonal variability in source water can lead to challenges for drinking water providers related to operational optimization and process control in treatment facilities. The objective of this study is to investigate seasonal variability of water quality in municipal small water systems （〈 3000 residents） supplied by surface waters. Residual chlorine and trihalomethanes （THM） were measured over seven years （2003-2009）. Comparisons are made within each system over time, as well as between systems according to the type of their treatment technologies. THM concentrations are generally higher in the summer and autumn. The seasonal variability was generally more pronounced in systems using chlorination plus additional treatment. Chloroform, total THM （TTHM） and residual chlorine concentrations were generally lower in systems using chlorination plus additional treatment. Conversely, brominated THM concentrations were higher in systems using additional treatment. Residual chlorine was highest in the winter and lowest in the spring and summer. Seasonal variations were most pronounced for residual chlorine in systems with additional treatment. There was generally poor correlation between THM concentrations and concentrations of residual chlorine. Further study with these data will be beneficial in finding determinants and indicators for both quantity and variability of disinfection byproducts and other water quality parameters.

关键词： drinking water residual chlorine seasonal variability small municipal systems treatment technologies trihalomethanes

Concentrations of disinfection by-products in swimming pool following modifications of the water treatment process:An exploratory study

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Journal of Environmental Sciences 2017年第8期29卷 163-172页

作者： Robert Tardif manuel rodriguez Cyril Catto Ginette Charest-Tardif Sabrina Simard Department of Environmental and Occupational Health School of Public HealthUniversité de Montréal NSERC Industrial Research Chair on Drinking Water Université Laval

The formation and concentration of disinfection by-products（DBPs） in pool water and the ambient air vary according to the type of water treatment process used. This exploratory study was aimed at investigating the short-term impact of modifications of the water treatment process on traditional DBP levels（e.g., trihalomethanes（THMs）, chloramines） and emerging DBPs（e.g., Halonitromethanes, Haloketones, NDMA） in swimming pool water and/or air. A sampling program was carried to understand the impact of the following changes made successively to the standard water treatment process： activation of ultraviolet（UV）photoreactor, halt of air stripping with continuation of air extraction from the buffer tank,halt of air stripping and suppression of air extraction from the buffer tank, suppression of the polyaluminium silicate sulfate（PASS） coagulant. UV caused a high increase of Halonitromethanes（8.4 fold）, Haloketones（2.1 fold）, and THMs in the water（1.7 fold） and, of THMs in the air（1.6 fold） and contributed to reducing the level of chloramines in the air（1.6fold） and NDMA in the water（2.1 fold）. The results highlight the positive impact of air stripping in reducing volatile contaminants. The PASS did not change the presence of DBPs, except for the THMs, which decrease slightly with the use of this coagulant. This study shows that modifications affecting the water treatment process can rapidly produce important and variable impacts on DBP levels in water and air and suggests that implementation of any water treatment process to reduce DBP levels should take into account the specific context of each swimming pool.

关键词： Disinfection by-products Swimming pool UV rays Air stripping Chloramines Emerging DBPs NDMA

Bone metastases as initial presentation of hepatocellular carcinoma

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World Journal of Hepatology 2017年第29期9卷 1158-1165页

作者： Luzdivina Monteserin Alicia Mesa Maria Soledad fernandez-Garcia Arantza Gadanon-Garcia manuel rodriguez María Varela Department of Gastroenterology and Hepatology Complejo Asistencial Universitario de León Department of Radiology Hospital Universitario Central de Asturias Department of Pathology Hospital Universitario Central de Asturias Department of Traumatology Hospital Universitario Central de Asturias Liver Unit Hospital Uni-versitario Central de Asturias

Extra-hepatic spread is present in 5% to 15% of patients with hepatocellular carcinoma(HCC) at the time of diagnosis. The most frequent sites are lung and regional lymph nodes. Here, we report 3 cases of unsuspected HCC with symptoms due to bone lesions as initial presentation. Morphological characteristics and immunohistochemistry from the examined bone were the key data for diagnosis. None of the patients had an already known chronic liver disease. Differential diagnoses with HCC upon ectopic liver disease or hepatoid adenocarcinoma were shown. Therapy with the orally active multikinase inhibitor sorafenib plus symptomatic treatment was indicated.

关键词： Hepatocellular carcinoma Bone metastases Liver cirrhosis Sorafenib