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The dinoflagellate Noctiluca scintillans exists in two forms, green and red Noctiluca, with and without the photosynthetic endosymbiont Pedinomonas noctilucae, respectively. In Southeast Asia, green Noctiluca has a northern boundary of distribution in the Luzon Strait and the Vietnamese coast, approximately corresponding to the 25°C isotherm. We examined whether this boundary arose from the growth dependence of Noctiluca on temperature and/or that of P. noctilucae. We analyzed the effect of temperature on growth by examining one and four unialgal cultures of red and green Noctiluca, respectively, and two monocultures of the endosymbiont. Growth dependence on temperature was markedly different between host cells of green Noctiluca and monocultures of the endosymbiont, although some variations in growing temperature were observed among strains of both Noctiluca and the endosymbiont. Green Noctiluca grew at a temperature range of 20–31°C, whereas P. noctilucae did not grow at low temperatures ≤25°C. Growth rates of green Noctiluca were considerably higher when fed compared to monocultures. Our findings demonstrate that the effect of temperature on P. noctilucae growth is a crucial factor controlling the geographical distribution of green Noctiluca in the South China Sea. An implication of this finding is discussed in the context of global warming.

The use of Compton cameras for medical imaging and its interest as a hadron therapy treatment monitoring has increased in the last decade with the development of silicon photomultipliers. MACACO is a Compton camera prototype designed and assembled at the IRIS group of IFIC-Valencia. This Compton camera is based on monolithic Lanthanum (III) Bromide crystals and silicon photomultipliers, and employs the novel TOFPET2 ASIC as readout electronics. This system emerged as an alternative to MACACO II prototype, with the aim of improving its limited time resolution. To test the performance of the ASIC in a Compton camera setup, the prototype was characterized, both in laboratory and in-beam. A time resolution of 1.5 ns was obtained after time corrections, which improves greatly the performance of the MACACO II. Moreover, the results obtained at high photon energies demonstrate the ability of the system to obtain 1 mm displacements of the reconstructed spots. The results reinforce the potential of the system as a monitoring device for hadron therapy., This work has received funding from the Generalitat Valenciana, Spain (AICO/2019070) and from the Spanish Ministerio de Ciencia e Innovación (PID2019-110657RB-100). Group members are supported by UVEG Atracció de Talent, FPU, CDEIGENT, SEJIGENT and Generalitat Valenciana contracts. M.C. Jiménez-Ramos acknowledges the support to this work through a VI PPIT-US contract.

En este estudio fueron evaluadas algunas variedades de cítricos utilizadas como interinjertos en las características del crecimiento inicial de brote primario de la lima persa var. ‘Tahiti’ (Citrus x latifolia Tanaka ex Q. Jiménez) y su relación con características del tallo. Se utilizaron como interinjertos trifoliado ‘Flying Dragon’ (Poncirus trifoliata var. ‘Monstruosa’), trifoliado ‘Rubidoux’ (P. trifoliata var. ‘Rubidoux’) y la propia lima ‘Tahiti’; y como portainjertos se utilizó el naranjo ‘Agrio’ (C. aurantium L.) y limón ‘Volkameriano’ (C. volkameriana Tenn. & Pasq.). Se realizó un diseño de tratamientos factorial 2 x 4. Se midieron siete variables del crecimiento inicial del injerto y seis características del tallo y se correlacionaron entre ellas. El ‘Agrio’ con los interinjertos redujo la longitud, velocidad de crecimiento, diámetro y longitud de entrenudos del brote primario en 18, 22, 12 y 14 % menos respecto a ‘Volkameriano’ con los interinjertos. ’Rubidoux’ sobre ‘Volkameriano’ tuvo los valores más altos en seis variables del crecimiento, pero combinado con ‘Agrio’ indujo características de enanismo en el brote primario de lima ‘Tahiti’. El diámetro de tallo de ambos portainjertos se afectó por el interinjerto. ´Rubidoux’ incrementó el diámetro de ‘Volkameriano’ pero no el de ‘Agrio’, mientras que ‘Flying Dragon’ presentó mayor diámetro que su portainjerto. Se encontraron correlaciones bajas ( -0.22 a 0.50) del diámetro del portainjerto y del interinjerto; del grosor de la corteza del portainjerto y del interinjerto con todas las variables del crecimiento del brote primario de lima ‘Tahiti’.

The applicability extent of hadron therapy for tumor treatment is currently limited by the lack of reliable online monitoring techniques. An active topic of investigation is the research of monitoring systems based on the detection of secondary radiation produced during treatment. MACACO, a multi-layer Compton camera based on LaBr3 scintillator crystals and SiPMs, is being developed at IFIC-Valencia for this purpose. This work reports the results obtained from measurements of a 150 MeV proton beam impinging on a PMMA target. A neural network trained on Monte Carlo simulations is used for event selection, increasing the signal to background ratio before image reconstruction. Images of the measured prompt gamma distributions are reconstructed by means of a spectral reconstruction code, through which the 4.439 MeV spectral line is resolved. Images of the emission distribution at this energy are reconstructed, allowing calculation of the distal fall-off and identification of target displacements of 3 mm.

Objective. To demonstrate the benefits of using an joint image reconstruction algorithm based on the List Mode Maximum Likelihood Expectation Maximization that combines events measured in different channels of information of a Compton camera. Approach. Both simulations and experimental data are employed to show the algorithm performance. Main results. The obtained joint images present improved image quality and yield better estimates of displacements of high-energy gamma-ray emitting sources. The algorithm also provides images that are more stable than any individual channel against the noisy convergence that characterizes Maximum Likelihood based algorithms. Significance. The joint reconstruction algorithm can improve the quality and robustness of Compton camera images. It also has high versatility, as it can be easily adapted to any Compton camera geometry. It is thus expected to represent an important step in the optimization of Compton camera imaging.

Strategic model analysis is required in a continuously changing environment where businesses must respond and fulfill the Sustainable Development Goals. These models must cover all the variables that can affect the environment for doing business within an industry. For this reason, it is proposed to create a sectoral analysis model that integrates the PEST and Porter's five forces analysis. The purpose of this qualitative research is to validate the relevance of the proposed model. The research is carried out based on the perception of a sample of students from the business administration program of the Politecnico Grancolombiano University in Colombia which used the application model proposed during the period 2020-2021. The authors found that with an average rating of 4.48 out of 5, the group of respondents positively values the usefulness of the model proposed.

The response of two chromatography techniques (GC) for electron capture (GC-ECD) and GC-coupled to a mass spectrometer with negative chemical ionization (GC-MS/NCI) was compared to validate the qua...

espanolEl objetivo de la investigacion fue implementar un programa de intervencion psicosocial en ninas/os con sobrepeso u obesidad y que logren identificar habitos alimenticios saludables. Se realizo un muestreo no probabilistico por conveniencia reclutando a 20 ninos y ninas con peso normal (n=4), sobrepeso (n=11) y obesidad (n=5) con un rango de edad de 8 a 12 anos (= 9.65). De la muestra inicial solo 16 ninos y ninas con sobrepeso u obesidad comenzaron el programa de intervencion y solo 9 participantes lo concluyeron. El estudio fue no experimental de tipo descriptivo de corte transversal donde las variables estudiadas fueron la alimentacion emocional, habitos alimenticios, creencias irracionales, funcionamiento familiar y depresion. Para el analisis de los resultados de la bateria se utilizaron tablas cruzadas con el fin de crear un plan de intervencion que respondiera a las necesidades de la poblacion encontrando que los participantes presentaban riesgo de alimentacion emocional, muestran ausencia de actividad fisica y presencia de creencias irracionales en torno a su alimentacion, indicativo de habitos alimenticios no saludables. Finalmente se aplico un pretest-postest, durante el programa de intervencion, donde se llevo a cabo un analisis descriptivo destacando la mejora de los habitos alimenticios de los participantes. EnglishThe objective of the research was to implement a psychosocial intervention program for children who are overweight or obese and enable them to identify healthy eating habits. A non-probability sample for convenience was carried out, recruiting 20 with normal weight (n=4), overweight (n=11) or obese (n=5) boys and girls with an age range of 8 to 12 years ( = 9.65). Of the initial sample, only 16 boys and girls that were overweight or obese started the intervention program and only 9 participants completed it. The study was non-experimental of a cross-sectional, descriptive, correlational type with a quantitative approach where the variables studied were emotional eating, eating habits, irrational beliefs, family functioning, and depression. In the analysis of the results of the battery, crossed tables were used in order to create an intervention plan that responded to the needs of the population, finding that the participants were at risk of emotional feeding, they also showed absence of physical activity and presence of irrational beliefs around their diet, which is an indicative of unhealthy eating habits. Finally, a pretest-posttest was applied during the intervention program, where a descriptive analysis was carried out highlighting improvement in the eating habits of the participants.

Rosmarinic acid is a hydroxycinnamic acid ester commonly found in the Boraginaceae and Lamiaceae plant families. It exhibits various biological activities, including antioxidant, anti-inflammatory, antibacterial, antiallergic, and antiviral properties. Rosmarinic acid is used as a food and cosmetic ingredient, and several pharmaceutical applications have been suggested as well. Rosmarinic acid is currently produced by extraction from plants or chemical synthesis; however, due to limited availability of the plant sources and the complexity of the chemical synthesis method, there is an increasing interest in producing this compound by microbial fermentation. In this study, we aimed to produce rosmarinic acid by engineered baker's yeast

International audience; The IRIS group at IFIC-Valencia has developed a second version of a Compton camera prototype for hadron therapy treatment monitoring, with the aim of improving the performance with respect to its predecessor. The system is composed of three Lanthanum (III) bromide (LaBr 3) crystals coupled to silicon photomultipliers (SiPMs). The detector energy resolution has been improved to 5.6 % FWHM at 511 keV and an angular resolution of 8.0 • has been obtained. Images of a 22 Na point-like source have been reconstructed selecting two and three interaction events. Moreover, the experimental data have been reproduced with Monte Carlo simulations using a Compton camera module (CCMod) in GATE v8.2 obtaining a good correlation.

One factor limiting the current applicability extent of hadron therapy is the lack of a reliable method for real time treatment monitoring. The use of Compton imaging systems as monitors requires the correct reconstruction of the distribution of prompt gamma productions during patient irradiation. In order to extract the maximum information from all the measurable events, we implemented a spectral reconstruction method that assigns to all events a probability of being either partial or total energy depositions. The method, implemented in a list-mode maximum likelihood expectation maximization algorithm, generates a four dimensional image in the joint spatial-spectral domain, in which the voxels containing the emission positions and energies are obtained. The analytical model used for the system response function is also employed to derive an analytical expression for the sensitivity, which is calculated via Monte Carlo integration. The performance of the method is evaluated through reconstruction of various experimental and simulated sources with different spatial and energy distributions. The results show that the proposed method can recover the spectral and spatial information simultaneously, but only under the assumption of ideal measurements. The analysis of the Monte Carlo simulations has led to the identification of two important degradation sources: the mispositioning of the gamma interaction point and the missing energy recorded in the interaction. Both factors are related to the high energy transferred to the recoil electrons, which can travel far from the interaction point and even escape the detector. These effects prevent the direct application of the current method in more realistic scenarios. Nevertheless, experimental point-like sources have been accurately reconstructed and the spatial distributions and spectral emission of complex simulated phantoms can be identified.

In recent decades, PET scanners have been widely used for diagnosis and treatment monitoring in nuclear medicine. The continuous effort of the scientific community has led to improvements in scanner performance. Total-body PET is one of the latest upgrades in PET scanners. These kinds of scanners are able to scan the whole body of the patient with a single bed position, since the scanner tube is long enough for the patient to fit inside. While these scanners show unprecedented efficiency and extended field-of-view, a drawback is their low spatial resolution compared to dedicated scanners. In order to improve the spatial resolution of specific areas when measuring with a total-body PET scanner, the IRIS group at IFIC-Valencia is developing a probe. The proposed setup of the probe contains a monolithic scintillation crystal and a SiPM. The signal of the probe is read out by a TOFPET2 ASIC from PETsys, which has shown good performance for PET in terms of spatial and time resolutions. Furthermore, the PETsys technology generates a trigger signal that will be used to time synchronise the probe and the scanner. The proof-of-concept of the probe will be tested in a Preclinical Super Argus PET/CT scanner for small animals located at IFIC. Preliminary simulations of the scanner and the probe under ideal conditions show a slight improvement in the position reconstruction compared to the data obtained with the scanner, therefore we expect a considerable improvement when using the probe in a total-body PET scanner. Characterisation tests of the probe have been performed with a 22Na point-like source, obtaining an energy resolution of 9.09% for the 511 keV energy peak and a temporal resolution of 619 ps after time walk correction. The next step of the project is to test the probe measuring in temporal coincidence with the scanner.

Compton Cameras are electronically collimated photon imagers suitable for sub-MeV to few MeV gamma-ray detection. Such features are desirable to enable in vivo range verification in hadron therapy, through the detection of secondary Prompt Gammas. A major concern with this technique is the poor image quality obtained when the incoming gamma-ray energy is unknown. Compton Cameras with more than two detector planes (multi-layer Compton Cameras) have been proposed as a solution, given that these devices incorporate more signal sequences of interactions to the conventional two interaction events. In particular, three interaction events convey more spectral information as they allow inferring directly the incident gamma-ray energy. A three-layer Compton Telescope based on continuous Lanthanum (III) Bromide crystals coupled to Silicon Photomultipliers is being developed at the IRIS group of IFIC-Valencia. In a previous work we proposed a spectral reconstruction algorithm for two interaction events based on an analytical model for the formation of the signal. To fully exploit the capabilities of our prototype, we present here an extension of the model for three interaction events. Analytical expressions of the sensitivity and the System Matrix are derived and validated against Monte Carlo simulations. Implemented in a List Mode Maximum Likelihood Expectation Maximization algorithm, the proposed model allows us to obtain four-dimensional (energy and position) images by using exclusively three interaction events. We are able to recover the correct spectrum and spatial distribution of gamma-ray sources when ideal data are employed. However, the uncertainties associated to experimental measurements result in a degradation when real data from complex structures are employed. Incorrect estimation of the incident gamma-ray interaction positions, and missing deposited energy associated with escaping secondaries, have been identified as the causes of such degradation by means of a detailed Monte Carlo study. As expected, our current experimental resolution and efficiency to three interaction events prevents us from correctly recovering complex structures of radioactive sources. However, given the better spectral information conveyed by three interaction events, we expect an improvement of the image quality of conventional Compton imaging when including such events. In this regard, future development includes the incorporation of the model assessed in this work to the two interaction events model in order to allow using simultaneously two and three interaction events in the image reconstruction.

A three-layer Compton Telescope, capable of measuring two and three-interaction events, is being developed at IRIS group (Image Reconstruction, Instrumentation and Simulations for medical imaging applications) of IFIC-Valencia. It is based on continuous LaBr 3 crystals coupled to SiPMs; consequently, a large number of projections can be obtained (high granularity). In order to achieve an accurate reconstruction process, precise estimations of the System Matrix and the Sensitivity Matrix are needed. Given that Monte-Carlo calculations of the aforementioned quantities are computationally expensive due to the high granularity of the imaging device, an analytical model would be advisable. The group has already proposed and assessed a model for two-interaction events. In the present work we propose a similar model for three-interaction events. Whereas three-interaction events allow to obtain the energy of incident gamma-rays without full-absorption requirement, efficiency loss and richer diversity of signal/background events must be handled. In this work we present a preliminary validation of the proposed model, by comparing its performance and predictions with Monte-Carlo simulations. Images of simulated point-like monochromatic sources, as well as a preliminary background study, are also reported.

Background β-Lactam antibiotics are the most common trigger of reactions in children with most of them being nonimmediate (85.5%), but proven allergy after the allergological workup is between 7% and 10%. There is no agreement on how to perform the provocation tests in these types of hypersensitivity reactions. Objective To determine whether or not repeated doses of the β-lactams are required to reproduce a nonimmediate reaction in children. Methods This is a retrospective observational study. We included children under 14 years who were referred for a nonimmediate reaction to β-lactams. All patients underwent a 1-day hospital provocation and were kept under observation at home during the following days for at least the time elapsed between the first dose and the symptoms of the index reaction. If no reaction was triggered, the patient resumed the provocation at home with 2 daily therapeutic doses for an equal of interval time. Results Ninety-seven patients were included in the study. A positive reaction was recorded in 14 of them (14.4%). The short hospital provocation triggered 3 immediate reactions and 8 delayed reactions. The home rechallenge developed 1 immediate reaction and 2 delayed reactions. Conclusions Nonimmediate reactions to β-lactams in children may be triggered with a 1-day provocation test. We suggest to perform a 1-day provocation test followed by an observational period of at least the time interval of the index reaction. If this challenge is negative, an extended home provocation could subsequently be carried out.

El objetivo de la presente investigacion fue estimar la elasticidad ingreso de la disposicion a pagar de los consumidores de servicios ambientales proporcionados por el parque recreativo de los Prismas Basalticos de Huasca de Ocampo, Hidalgo. La importancia del estudio radica en las recomendaciones de politica ambiental para hacer que el ecosistema de los Prismas Basalticos sea sustentable economicamente mediante el cobro diferencial de cuotas de entrada. La metodologia utilizada fue la segmentacion de los consumidores a partir del modelo de analisis de conglomerados en dos etapas. El principal resultado fue la identificacion de tres tipos de consumidores, quienes los de menor ingreso tienen mayor disponibilidad a pagar por mejoras potenciales en los servicios recreativos del parque, mientras que los de mayores ingresos tienen menor disponibilidad a pagar. Los resultados indican que, en los tres tipos de consumidores, la elasticidad ingreso de la disponibilidad al pago por mejoras potenciales a la calidad de los servicios recreativos es menor que la unidad y mayor que cero; es decir, que los servicios recreativos son un bien normal. El resultado es relevante y consistente con los reportados en otras investigaciones.

Saccharomyces cerevisiae is one of the key cell factories for production of chemicals and active pharmaceuticals. For large-scale fermentations, particularly in biorefinery applications, it is desirable to use stress-tolerant industrial strains. However, such strains are less amenable for metabolic engineering than the standard laboratory strains. To enable easy delivery and overexpression of genes in a wide range of industrial S. cerevisiae strains, we constructed a set of integrative vectors with long homology arms and dominant selection markers. The vectors integrate into previously validated chromosomal locations via double cross-over and result in homogenous stable expression of the integrated genes, as shown for several unrelated industrial strains. Cre-mediated marker rescue is possible for removing markers positioned on different chromosomes. To demonstrate the applicability of the presented vector set for metabolic engineering of industrial yeast, we constructed xylose-utilizing strains overexpressing xylose isomerase, xylose transporter and five genes of the pentose phosphate pathway. Electronic supplementary material The online version of this article (doi:10.1007/s10295-015-1684-8) contains supplementary material, which is available to authorized users.

The IRIS group of IFIC-Valencia has developed and fully characterized a first version of MACACO (Medical Applications CompAct COmpton camera), a three-layer Compton telescope based on LaBr 3 crystals and SiPMs for treatment monitoring in hadron therapy. Results obtained in laboratory and beam tests have demonstrated the feasibility of the proposed technology. The limitations of this first version of MACACO have been identified, being energy resolution one of the most critical parameters in the system performance. For this reason, an improved version of the detectors employing a new SiPM array has been assembled. Characterization tests have been performed. Also, coincidence tests have been carried out with two new detectors operated in time coincidence. Point-like sources and an array of 37 point-like sources have been imaged. Tests with the new detectors show a general improvement of the device performance.

A wood type preserved in Oligocene sediments of Coayuca de Andrade, Puebla, Mexico, is described and compared to Loxopterygium Hook. f. (Anacardiaceae). Among the characters that sustain this assignment are growth rings are marked by 2–3 rows of flattened latewood fibers. The vessel elements are circular to oval, predominantly solitary and radial multiples of 2 and 3. The perforation plates are simple, intervascular pits are alternate, oval and polygonal, with lenticular apertures, some of them are coalescent. Axial parenchyma is paratracheal scanty. Rays correspondent to the heterogeneous Kribs type IIB and one to two radial canals occur in multiseriate rays. These same characteristics are important to distinguish it from the extant species in the genus and support the recognition of a new species, Loxopterygium andradensii Mendez-Cardenas et al. The presence of this new species in the Cenozoic of Mexico confirms the importance of Anacardiaceae in the flora and vegetation of low latitude North America, reinforcing the idea that some elements of the Neotropical flora were in North America before the Plio-Pleistocene Great Biotic exchange and that at some point it was important for the diversification of some taxa.

In recent years, it has become recognized that patients with eosinophilic esophagitis (EoE) have an increased risk of multiple autoimmune diseases. Possible shared genetic aetiologies have been observed between EoE and autoimmune diseases. Currently, it is believed that EoE is not associated with a higher risk of neoplasms since such published cases are very rare and there are only isolated reports. Herein, we describe a unique case of EoE due to gluten without coeliac disease. The patient presented some unusual comorbidities, such as hypothyroidism (autoimmune disease) and essential thrombocythemia (neoplasm of haematologic origin).

jir_ 1341 1116 .. 1129 Abstract Background Perception disorders are frequently observed in persons with intellectual disability (ID) and their influence on cognition has been discussed. The objective of this study is to clarify the mecha- nisms behind these alterations by analysing the visual event related potentials early component, the N1 wave, which is related to perception alterations in several pathologies. Additionally, the relationship between N1 and neuropsychological visual tests was studied with the aim to understand its functional significance in ID persons. Method A group of 69 subjects, with etiologically heterogeneous mild ID, performed an odd-ball task of active discrimination of geometric figures. N1a (frontal) and N1b (post-occipital) waves were obtained from the evoked potentials.They also per- formed several neuropsychological tests.

Breeding system of Glandularia peruviana, G. platensis and G. glandulifera was studied through self and cross hand pollination experiments and observations of in vivo pollen tube growth. Self-pollinated flowers produced no fruits in all species. In cross pollination experiments, the reproductive success was 33, 8 and 63% for G. peruviana, G. platensis and G. glandulifera, respectively. In the three species, pollen grains germinated normally on the stigma of self and cross pollinated pistils, further growth of the pollen tube was inhibited at different parts of the style or in the ovary when self pollination occurred. Self-incompatibility system was confirmed since no fruits were obtained in self-pollinated pistils. Pollen tube arriving to the ovary in self-pollinated pistils suggested late acting self incompatibility system.

Arabidopsis thaliana transgenic plants with constitutive overexpression of the aspartic protease gene At2g28010 (named CDS10) showed a bushy, multi-branching dwarf phenotype. In order to obtain compact plants of ornamental interest with an analogous phenotype in Pelargonium zonale, a tall cultivar (Boda Gitana Salmon) was transformed to over express the A. thaliana CDS 10 gene under the 35S promoter. Twenty seven transgenic lines were obtained with different levels of expression after gold particle bombardment and regeneration. Some of them showed indeed a bushy phenotype with a higher number of branches and a dwarf phenotype. However, an increase in the number of branches correlated with a decrease in the number of petals in the flowers. So the plants that were of interest from the compact habit point of view, had lost the double flower trait, and exhibited only 5 petals/flower which were also smaller than those from double flowers from the non transformed plants. Intermediate phenotypes with semi-double flowers and higher number of branches but without a compact phenotype were also observed. In order to determine if it was genotype related two other cultivars were transformed, Mirada Violet and Mirada Simple Pink double and single flower cultivars respectively. Transgenic plants showed indeed a higher number of branches and single flowers. Even if the busy phenotype was of interest in order to get a higher number of cuttings/plant and a compact phenotype, the pleiotropic effects of the overexpression of the A. thaliana CDS 10 gene on the flowers are too strong meaning it is only of interest in single flowered cultivars which are a small share of the market. (Resume d'auteur)

SummaryLeaves and stem segments of in vitro-cultured Calibrachoa excellens were used as explants to obtain transgenic hairy roots after inoculation with the following strains of Agrobacterium rhizogenes: LBA 15834, LBA 8490, LMG 155, and A13. Only leaves showed sensitivity towards Agrobacterium infection. A. rhizogenes strain LBA 15834 was the most virulent among the four strains tested, with 33% of leaves showing root and callus proliferation, while only 10% of the explants showed root and/or callus development using strain A13, and no responses were observed in explants infected with the other two strains used. Two different transformation events were recovered as transgenic plants regenerated from hairy roots via spontaneous organogenesis. These plants showed, to different degrees, the classic symptoms of hairy root disease. PCR analysis of the recovered plants showed the presence of the rol A, rol B, rol C, and rol D genes, and the absence of the vir D1 gene, confirming the absence of Agrobacterium. S...

En este artículo se presentan las propiedades físicas y mecánicas del culmo de Guadua aculeata. El material de estudio se colectó en el predio “Las Margaritas”, Hueytamalco, Puebla, México. El marcado, derribo y ensayo se realizó tomando como referencia las normas ISO 22157-1 ISO e ISO/TR 22157-2. Se presentan valores promedio de los resultados para las secciones inferior, media y superior; se observa que la densidad básica (peso anhidro/volumen verde) varia de 560 a 660 kg/m3 de la base a la parte superior del culmo. Las contracciones totales promedio fueron de 13,9 % en espesor; 7,1 % en diámetro y 0,1 % en longitud. En el caso de las propiedades mecánicas se encontró que el esfuerzo máximo cortante varió de 6,0 a 10,5 MPa; el esfuerzo máximo en compresión paralela a la fibra incrementó de 28,2 a 56,7 MPa de la sección inferior a la superior y su módulo de elasticidad de 13,7 a 20,7 GPa. El módulo de ruptura en flexión de 51,9 a 79,6 MPa y su módulo de elasticidad de 15,1 a 24,1 GPa. La resistencia en tensión paralela a la fibra se incrementó de 58,5 a 92,2 MPa y el módulo de elasticidad en ese esfuerzo de 8,2 a 9,8 GPa. La especie estudiada tiene propiedades físicas, mecánicas y geométricas similares a la G. angustifolia que se utiliza en la construcción en países como Colombia, Costa Rica, Panamá, Venezuela y Ecuador. The physical and mechanical properties of Guadua aculeata culm are shown in this paper. The study material was collected from the locality “Las Margaritas” Hueytamalco, Puebla, Mexico. The marking, felling and testing was performed with reference to ISO standards ISO 22157-1 and ISO/TR 22157-2. The average values of the results of low, middle and upper sections are shown; the basic density (dry weight / green volume) ranged from 560 to 660 kg/m3 of the lower to upper culm section. The average total contractions were 13,9% in thickness; 7,1% in diameter and 0,1% in length. In the case of mechanical properties were found that the maximum shear stress varies from 6,0 to10,5 MPa; the maximum stress in compression parallel to fiber increased from 28,2 to 56,7 MPa from low to top section and the modulus of elasticity from 13,7 to 20,7 GPa. The modulus of rupture in bending varies from 51,9 to 79,6 MPa and the modulus of elasticity from 15,1 to 24,1 GPa. The strength in tension parallel to the fiber also increased from 58,5 to 92,2 MPa and modulus of elasticity ranged from 8,2 to 9,8 GPa. The studied specie has the same physical, mechanical and geometric properties to G. angustifolia that it is used in the construction in countries how Colombia, Costa Rica, Panama, Venezuela and Ecuador.

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Geraniums (Pelargonium spp.) are traditional ornamental plants largely cultivated in Europe and northern America. Vegetative propagation makes them prone to viral infections, which have detrimental effects on crop production and quality. Asymptomatic samples collected in Spain were tested for a range of viruses using ELISA. The tobamovirus, Tobacco mosaic virus (TMV), the cucumovirus, Cucumber mosaic virus (CMV), and several viruses in the family Tombusviridae, namely, Pelargonium line pattern virus (PLPV), Pelargonium flower break virus (PFBV), and Pelargonium leaf curl virus (PLCV), were detected either singly or in combination in 59.2% of 800 samples. PLPV and PFBV infections were confirmed by dot-blot hybridisation. The most relevant viral infection found on Spanish asymptomatic geraniums was by Pelargonium line pattern virus (PLPV). Symptoms did not develop for 3 years on most of the PLPV infected geranium plants under greenhouse conditions.

Meristem culture and/or thermotherapy were used for virus elimination from ornamental Phlox paniculata L. (`Blue Boy', `Orange perfection' and `Starfire') mother plants. Shoot tip, leaf, node and flower ovary explants collected from greenhouse-maintained virus free plants were cultured in vitro for shoot initiation. Adventitious shoot initiation was observed on Murashige and Skoog (MS) medium containing the cytokinin BA with or without the auxin NAA. The addition of 0.4 mg·L-1 thiamine, 0.4 mg·L-1 folic acid, and 40 mg·L-1 adenine sulfate to the MS medium did not improve the regeneration rate. Multiplication and rooting were genotype dependent. Blue Boy and Orange Perfection cultivars regenerated the maximum number of shoots from leaf explants. `Blue Boy' leaf explants from in vitro plants had a lower regeneration rate than explants from greenhouse plants. Cultivar `Starfire' had the highest shoot formation with open flower ovary explants and failed to regenerate from leaf explants. In vitro rooting of adventitious shoots in the presence of auxins (IAA, NAA, or IBA) with or without BA was less effective than ex vitro rooting. Chemical names used: 6-benzyladenine (BA); indole-acetic acid (IAA); indole-3-butyric acid (IBA); α-naphthaleneacetic acid (NAA).

Meristem culture and/or thermotherapy were used to eliminate viruses from ornamental Dianthus gratianopolitanus Vill. (`Spotti' and `Frosty Fire') mother plants. Shoot tip, leaf, node, and ovary explants collected from greenhouse-maintained, virus-free plants were cultured in vitro for shoot initiation on Murashige and Skoog (MS) medium containing BAP, kinetin, or 2-iP with or without IAA or NAA. Culture of shoot tips in MS with 0.57 μm IAA and node explants in MS with 2.46 μm 2-iP is recommended for `Spotti' cultivar. In `Frosty Fire', optimum number of axillary shoots was obtained from shoot tip and node explants in MS without plant regulators. Leaves and ovaries were not adequate explants for D. gratianopolitanus micropropagation because none or only a low percentage of explants regenerated shoots. High levels of cytokinins increased the number of shoots per explant but also increased the production of aberrant phenotypes and induced hyperhydricity. Adventitious shoots rooted in vitro with auxins, but maximum rooting was 97% ex vitro without auxins. This study demonstrated that D. gratianopolitanus can be successfully micropropagated. Chemical names used: 6-benzyladenine (BAP); kinetin (KIN); 6-(γ,γ-dimethylallylamino)-purine (2iP); indole-acetic acid (IAA); indole-3-butyric acid (IBA); α-naphthaleneacetic acid (NAA); gibberellic acid (GA3).