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In this paper, we describe the process that we used to create a new corpus of children’s emotional speech. We used a Wizard of Oz (WoZ) setting to induce different emotional reactions in children during speech-based interactions with two robots. We recorded the speech spoken in Mexican Spanish by 174 children (both sexes) between 6 and 11 years of age. The recordings were manually segmented and transcribed. The segments were then labeled with two types of emotional-related paralinguistic information: emotion and attitude. The corpus contained 2093 min of audio recordings (34.88 h) divided into 19,793 speech segments. The Interactive Emotional Children’s Speech Corpus (IESC-Child) can be a valuable resource for researchers studying affective reactions in speech communication during child-computer interactions in Spanish and for creating models to recognize acoustic paralinguistic information. IESC-Child is available to the research community upon request.

Due to the problems presented in current traditional/biometric security systems, the interest to use new security systems, have been increasing. This paper explores the use of brain signals EEG-based during imagined speech in order to use it as a new biometric measure for Subjects identification and thus create a new biometric security system. The main contribution of this paper are two methods for feature extraction, first to improve the signal-to-noise ratio the Common Average Reference was applied. The first method was based on Discrete Wavelet Transform, and the second method was based on statistical features directly from the raw signal. The proposed methods were tested in a dataset of 27 Subjects who performed 33 repetitions of 5 imagined words in Spanish. The results show the feasibility of the task with accurate identification of the Subject, regardless of the imagined word used and using a commercial EEG system (EMOTIV EPOC). In addition, the scope of the method is displayed by decreasing the training data, as well as the number of active sensors for the identification task. Using the proposed method with future improvements and implementing it in a low-cost device can be a new and valuable biometric security system.

E-communication represents a major threat to users who are exposed to a number of risks and potential attacks. Detecting these risks with as much anticipation as possible is crucial for prevention. However, much research so far has focused on forensic tools that can be applied only when an attack has been performed. This paper proposes a novel and effective methodology for the early detection of threats in written social media. The goal is to recognize a potential attack before it is consummated, and using a minimum amount of information. The proposed approach considers the use of profile-based representations (PBRs) for this goal. PBRs have multiple benefits, including non-sparsity, low dimensionality, and a proved discriminative power. Moreover, representations for partial documents can be derived naturally with PBRs, which makes them suitable for the addressed problem. Results include empirical evidence on the usefulness of PBRs in the early recognition setting for two tasks in which anticipation is critical: sexual predator detection and aggressive text identification. These results reveal, on the one hand, that PBRs achieve state of the art performance when using full-length documents (i.e., the classical task), and, on the other hand, that the proposed methodology outperforms previous work on early recognition of sexual predators by a considerable margin, while obtaining state of the art performance in aggressive text identification. To the best of our knowledge, these are the best results reported on early recognition for the approached problems. We foresee this work will pave the way for the development of novel methodologies for the problem and will motivate further research from the intelligent systems and text mining communities.

EEG-based Brain–Computer Interfaces (BCI) are an alternative technique that aims to integrate people with severe motor disabilities to their environment. However, they still are not used in everyday life because BCIs are controlled by means of few intuitive electrophysiological sources. To address this problem, work has been carried out with the objective of classifying EEG signals recorded while imagining speech. In this paper, the emerging techniques of sonification and textification are applied to EEG signals, which allows us to characterize EEG signals as either an audio signal or a text document. The aim is to analyze whether these techniques can help to do a better discrimination or to highlight patterns, and assess which of the two methods performs better in order to improve classification results of unspoken words. For proving this we processed signals, from 27 subjects, with and without the application of the proposed methods of sonification and textification. The average accuracy rate using the original EEG signals, the EEG sonified signals and the EEG textified signals are 58.41 ± 12.41%, 63.82 ± 13.44% and 83.34 ± 6.12%, respectively. It can be clearly noticed that the methods of sonification and textification of EEG improve the classification rates obtained using the EEG signals in their original form.

"Pinaceae is the most species rich conifer family in Mexico. Here we describe the diversity and geographic distribution of the family in the state of Puebla based on revision of herbarium specimens and field exploration. 572 georeferenced records for 15 species and 1 variety were mapped. These were included in potential distribution models to predict the most species-rich regions in the state and quantify the known species distributions in 10 ? × 10 ? (latitudinal × longitudinal) cells. The conservation status of each taxon was evaluated by calculating its area of occupation and conservation category within the state. A species–accumulation curve agreed with the number of taxa employed, suggesting that the family is relatively well sampled. The resulting potential distribution models indicated that the regions of highest predicted diversity in the state correspond well to the actual diversity estimates, although in some sites more species were predicted than were recorded. The Sierra Madre Oriental and the Trans-Mexican Volcanic Belt were the biogeographic regions with the greatest known and potential richness. Finally, the regional evaluation of conservation status provides relevant information for local conservationists and authorities, given that 12 of the 16 taxa were determined to be at risk. © 2017 Universidad Nacional Autónoma de México, Instituto de Biología. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )."

Resumen La Sierra Madre Oriental ha perdido hasta el 30% de su vegetacion, lo que hace imperativo conocer mejor su biodiversidad, asi como las variables ambientales que explican su distribucion. En la Sierra Madre Oriental es posible diferenciar 4 regiones climaticas, pero nunca se ha evaluado su relacion con la biodiversidad. Se propone una evaluacion con base en los dominios climaticos que la caracterizan y analizar su relacion con la diversidad floristica, representada por la familia Asteraceae. Se definieron dominios mediante analisis multivariados, utilizando datos de 19 parametros climaticos con el paquete ANUCLIM, a 1 km2. A partir de una clasificacion no jerarquica, se hizo posteriormente una reclasificacion jerarquica empleando la metrica de Gower y un agrupamiento utilizando el metodo UPGMA. Se reconocen 277 dominios climaticos en la Sierra Madre Oriental, los cuales se emplearon para explicar sus relaciones con la vegetacion y para estimar la riqueza de Asteraceae en dichos dominios. El bosque templado es el bioma con mayor riqueza de especies y tiene una alta correlacion geografica con uno de los dominios climaticos obtenidos. Los resultados permiten aportar informacion que seguramente sera de utilidad para definir futuras acciones de conservacion de la biodiversidad en la region.

This study evaluated low salinity effect on acute Hg toxicity and bioconcentration capacity in L. vannamei juveniles (8.4 ± 0.7 g), because this species is frequently exposed to hypo-osmotic environments in its natural habitat, and in farming ponds. Hg LC50 values were 1723, 1272, 983 and 536 μg L−1 at salinity of 5 ppt (parts per thousand); 2203, 1740, 1340 and 873 μg L−1 at 10 ppt; and 7013, 5693, 1759 and 1534 μg L−1 at 25 ppt for 24, 48, 72 and 96 h, respectively. After 96 h, acute Hg toxicity in shrimp was significantly higher in salinity of 5 ppt than in 25 ppt; likewise, Hg bioconcentration in shrimp exposed to different Hg treatments was statistically greater in salinity of 5 ppt than in 25 ppt. The chemical speciation calculated in experimental waters suggested that neutral chemical Hg species (HgCl2 and HgClOH) were the most bioavailable because their fractions (51–62%) increased when salinity decreased. Therefore, the inverse relationship between Hg toxicity and salinity was due to osmotic stress and the neutral chemical Hg species fractions that increased at lower salinities. Hg bioconcentration factors indicated that the higher Hg waterborne concentrations were the most saturated uptake and storage mechanisms in shrimp. Thus, Hg concentrations in organisms did not increase in proportion to waterborne Hg concentrations in the three salinities. These results support the hypothesis of an effect of low salinity on Hg toxicity and bioconcentration capacity in L. vannamei. The safe Hg concentrations 5.4, 8.7 and 15.3 μg L−1 were proposed for shrimp exposed to salinity of 5, 10 and 25 ppt, respectively. This information allows recognizing risky environments for both wild and cultured healthy growth of these shrimp, which can help decision makers on coastal management and shrimp pond managers to have better water quality.

It was searched the minimal subset of channels for imagined speech.Channel selection was approached as multi-objective to obtain a Pareto front.A fuzzy system inference was applied to find a promising solution from Pareto front.Channel selection had a statistically similar performance to the use of all channels.It was observed a dependence between features and classes of imagined speech. One of the main purposes of brain-computer interfaces (BCI) is to provide persons of an alternative communication channel. This objective was firstly focused on handicapped subjects but nowadays its scope has increased to healthy persons. Usually, BCIs record brain activity using electroencephalograms (EEG), according to four main neuro-paradigms (slow cortical potentials, motor imagery, P300 component and visual evoked potentials). These analytical paradigms are not intuitive and are difficult to implement. Accordingly, this work researches an alternative neuro-paradigm called imagined speech, which refers to the internal pronunciation of words without emitting sounds or doing facial movements. Specifically, the present research is focused on the recognition of five Spanish words corresponding to the English words "up," "down," "left," "right" and "select", with which a computer cursor could be controlled. We perform an offline computer automatic classification procedure of a dataset of EEG signals from 27 subjects. The method implements a channel selection composed of two stages; the first one obtains a Pareto front and is approached as a multi-objective optimization problem dealing with the error rate and the number of channels; the second stage selects a single solution (channel combination) from the front, applying a fuzzy inference system (FIS). We assess the method's performance through a channel combination and a test set not used to generate the front. Several FIS configurations were explored to evaluate if a FIS is able to select channel combinations that improve or, at least, keep the obtained accuracies using all channels for each subject's data. We found that a FIS configuration, FIS3×3 (three membership functions for both input variables: error rate and the number of channels), obtained the best trade-off between the number of fuzzy rules and its accuracy (68.18% using around 7 channels). Also, the FIS3×3 obtained a similar statistically accuracy compared to the use of all channels (70.33%). Results of our method demonstrate the feasibility of using a FIS to automatically select a solution from the Pareto front to select channels applied to a problem of imagined speech classification. The presented method outperforms previous works in accuracy and showed a dependence relationship between EEG data and imagined words.

An updated inventory of the native vascular plants of Mexico records 23,314 species, distributed in 2,854 genera, 297 families, and 73 orders. The flora includes 1,039 species of ferns and lycophytes, 149 gymnosperms, and 22,126 angiosperms. On average, the number of synonyms per species is 1.3 (mode=1). The number of species places Mexico as the country with the fourth largest floristic richness in the world, although among the non-insular countries, by its number of endemic species (about 50%) is second only surpassed by South Africa. The species distribution among higher taxonomic categories, and the richness and endemism values in the 32 states of Mexico are discussed. This compilation allows us to assess the flora's contribution to the overall Mexican biodiversity.

The phytochemical study of the aerial parts of Verbesina sphaerocephala A. Gray afforded six sesquiterpene lactones of cadinene type, five of them described for the first time, along with known phenyl propanoids, terpenoids, and phenolic compounds. Structures on new compounds were elucidated by spectroscopic techniques including CD and X-ray analyses, and known compounds were identified by comparing their spectral data with those previously reported. Cadinene-like sesquiterpene lactones could be characteristic metabolites of V. sphaerocephala.

The Author Profiling (AP) task aims to reveal as much as possible information from a given author's document (e.g., age, gender, etc.). AP is crucial for several applications, ranging from customized advertising to computer forensics, psychology, and entertainment. Nonetheless, the AP task is far from being solved, particularly in social media domains, where the nature of documents hinder the applicability of state-of-the-art text mining tools (e.g., because of spelling-grammar errors, huge vocabularies, and the presence of many out-of-vocabulary terms). Currently, most of the work in AP for social media has been devoted to the development of descriptive features, which are used under standard representations, such as the Bag-of-Words (BoW). Nevertheless, BoW-like representations have some well known shortcomings, namely: (i) the sparsity and high dimensionality of the representation, and (ii) the failure to capture relationships, other than mere occurrence, among terms. This paper focuses on the study of alternative document representations that can deal with such issues. We propose a representation for documents that capture discriminative and subprofile-specific information of terms. Under the proposed representation, terms are represented in a vector space that captures discriminative information. Then, term representations are aggregated to represent the content of a document. In this manner, documents are represented in a low-dimensional (and discriminative) space which is non-sparse. We evaluate the effectiveness of the proposed representation on several corpora from the social media domain. The proposed representation is compared to the standard BoW representation and a wide variety of state-of-the-art AP approaches. Experimental results reveal that the proposed representation outperforms most of the reference methodologies. Furthermore, we show that the proposed representation is in agreement with previous studies on handcrafted attributes for AP.

ResumenEn México los sistemas de áreas protegidas no dan respuestas a las demandas de conservación de la biodiversidad. Se necesita evaluar la eficiencia de las ya establecidas y emplear algoritmos adecuados que informen cómo seleccionar sitios adicionales para conservar la mayor biodiversidad. El uso de algoritmos metaheurísticos, como los implementados en el software ConsNet, asegura la representatividad de atributos de conservación (por ejemplo, especies) considerados subrogados de la biodiversidad en hábitats naturales. Con datos de la distribución geográfica de especies de la familia Asteraceae, distribuidas en la región del Bajío, México, se generaron modelos de nicho ecológico haciendo uso del programa MaxEnt. Los modelos se emplearon como sustitutos de la biodiversidad para definir sitios idóneos para su conservación. Los sitios definidos se ubicaron mediante un análisis de complementariedad con algoritmos implementados en ConsNet. Se definió una red de áreas de conservación en regiones con vegetación primaria y se determinaron zonas irremplazables, por ser sitios donde se distribuyen especies restringidas a su territorio. La red de áreas de conservación obtenida tiene una baja coincidencia geográfica con las áreas naturales protegidas decretadas en el Bajío. Consideramos que este trabajo puede ser una propuesta útil para evaluar y eventualmente redefinir las áreas prioritarias de conservación en el Bajío y regiones adyacentes.AbstractIn Mexico, the natural protected areas do not fulfill the biodiversity conservation demands and many of them lack of clear mechanisms for management and conservation of their natural resources. It is necessary to evaluate how efficient are those already established and to employ adequate algorithms that maximize complementarity and other biological aspects required in the conservation of biodiversity. Actually, the use of meta-heuristic algorithms, as those implemented in ConsNet software ensure representativeness of conservation items (for example species), considered biodiversity surrogates for regions still including natural habitats. With geographical distribution data, the ecological niche models of species of the family Asteraceae distributed in the Bajio region in central Mexico were carried out using the MaxEnt program. Such models were employed as biodiversity surrogates to determining important areas for biodiversity conservation using the algorithms implemented in ConsNet. A network of conservation areas (RAC) where natural vegetation still persists was built and located places considered as irreplaceable because contain species restricted to their territory. The RAC obtained shows low coincidence with the extant natural protected areas in the Bajio region. We considered this study could help to evaluate and eventually re-define the natural protected system of the region.

Stramentopappus congestiflorus Redonda-Martínez and Villaseñor (Asteraceae: Vernonieae: Leiboldiinae) from Sierra de Juárez in Oaxaca, Mexico, is described and illustrated. It is distinguished from the other species of the genus by its tightly-clustered capitula forming glomerules and by fewer florets per capitulum. A key to the 2 species is provided.

Mexico maintains several databases with biotic or abiotic information that enable large scale-studies (for example, at a resolution of 1 km2); unfortunately, there is no information at this resolution for soil properties. The goal of this paper was to generate a set of soil variables to address this absence. We evaluated 4400 soil samples taken on Mexican territory. The following nine soil properties were evaluated for each sample: Ca, K, Mg, Na, organic C, organic matter, electrical conductivity, sodium absorption ratio, and pH. With the use of geostatistical methods, a layer was generated for each soil property after six different semivariance models were evaluated. The kriging model (simple, ordinary, or universal) was selected as the best semivariance method with a 10-fold cross-validation approach. Exponential, pentaspherical, and spherical models were selected with ordinary and universal kriging methods to spatially predict the soil properties. Five classes for each soil map were generated. The nine soil properties were classified primarily as slightly low or medium according to their distribution throughout Mexican territory.

An important task in plagiarism detection is determining and measuring similar text portions between a given pair of documents. One of the main difficulties of this task resides on the fact that reused text is commonly modified with the aim of covering or camouflaging the plagiarism. Another difficulty is that not all similar text fragments are examples of plagiarism, since thematic coincidences also tend to produce portions of similar text. In order to tackle these problems, we propose a novel method for detecting likely portions of reused text. This method is able to detect common actions performed by plagiarists such as word deletion, insertion and transposition, allowing to obtain plausible portions of reused text. We also propose representing the identified reused text by means of a set of features that denote its degree of plagiarism, relevance and fragmentation. This new representation aims to facilitate the recognition of plagiarism by considering diverse characteristics of the reused text during the classification phase. Experimental results employing a supervised classification strategy showed that the proposed method is able to outperform traditionally used approaches. 2012 Elsevier Ltd. All rights reserved., This work was done under partial support of CONACyT project Grants: 134186, and Scholarships: 258345/224483. This work is the result of the collaboration in the framework of the WIQEI IRSES project (Grant No. 269180) within the FP 7 Marie Curie. The work of the last author was in the framework of the VLC/CAMPUS Microcluster on Multimodal Interaction in Intelligent Systems.

In this paper we report the results obtained from experiments with a database of emotional speech in English in order to find the most important acoustic features to estimate Emotion Primitives which determine the emotional content on speech. We are interested in exploiting the potential benefits of continuous emotion models, so in this paper we demonstrate the feasibility of applying this approach to annotation of emotional speech and we explore ways to take advantage of this kind of annotation to improve the automatic classification of basic emotions.

Question answering (QA) is the task of automatically answering a question posed in natural language. Currently, there exists several QA approaches, and, according to recent evaluation results, most of them are complementary. That is, different systems are relevant for different kinds of questions. Somehow, this fact indicates that a pertinent combination of various systems should allow to improve the individual results. This paper focuses on this problem, namely, the selection of the correct answer from a given set of responses corresponding to different QA systems. In particular, it proposes a supervised multi-stream approach that decides about the correctness of answers based on a set of features that describe: (i) the compatibility between question and answer types, (ii) the redundancy of answers across streams, as well as (iii) the overlap and non-overlap information between the question-answer pair and the support text. Experimental results are encouraging; evaluated over a set of 190 questions in Spanish and using answers from 17 different QA systems, our multi-stream QA approach could reach an estimated QA performance of 0.74, significantly outperforming the estimated performance from the best individual system (0.53) as well as the result from best traditional multi-stream QA approach (0.60).

Centro de Investigaciones Biologicas del Noroeste (CIBNOR), La Paz, B.C.S. 23096, Mexico b Unidad de Acuacultura y Manejo Ambiental, Centro de Investigacion en Alimentacion y Desarrollo (CIAD), Apdo. Postal 711, Mazatlan, Sinaloa 82000, Mexico abstract article i nfo We studied the effects of four strains of Bacillus isolated from the guts of healthy wild adult shrimp on sur- vival and rate of development of whiteleg shrimp Litopenaeus vannamei larvae to understand how endemic Bacillus probiotic strains improve the health of larvae. This included bacterial isolation, assays of hemolytic activity, antagonism against pathogenic Vibrio species, growth, and adhesion to shrimp intestinal mucus, and molecular identification. Bacillus strains were tested on larval shrimp using a daily concentration of 1×10 5 CFU mL -1 , starting each bioassay at nauplii V at a density of 225 nauplii L �1 . Inoculations of four nat- ural, commercial products and antibiotic oxytetracycline were added directly to the water. All treatments in- duced a significant increase in survival compared to the control, with strain YC5-2 showing the highest survival (~67%), followed by Alibio MR (~57%). A mix of two strains induced the highest rate of development

Muon telescopes have multiple applications in the area of cosmic ray research. We are currently building such a detector with the objective of comparing the ground penetration of muon vs. electron-gamma signals originated in cosmic ray showers. The detector is composed by a set of three parallel dual-layer scintillator planes, buried at fixed depths ranging from 120 to 600 g / cm 2 . Each layer is 4 m 2 and is composed by 49 rectangular strips of 4 cm × 2 m , oriented at a 90 ∘ angle with respect to its companion layer, which gives an xy -coincidence pixel of 4 × 4 cm 2 . The scintillators are MINOS extruded polystyrene strips, with an embedded Bicron BC92 wavelength shifting (WLS) fibers, of 1.5 mm in diameter. Light is collected by Hamamatsu H7546B multi-anode PMTs of 64 pixels. The front-end (FE) electronics works in counting mode and signals are transmitted to the surface DAQ stage using low-voltage differential signaling (LVDS). Any strip signal above threshold opens a GPS-tagged 2 μ s data collection window. Data, including signal and background, are acquired by a system of FPGA (Spartan 2E) boards and a single-board computer (TS7800).

Michoacan, as one of the most species-rich provinces of Mexico and with high levels of endemism, was used for testing the potential of a conservation approach based on biodiversity as determined by scientists and local stakeholder's preferences. The resulting zones covered over 17% of the area of Michoacan in 18 zones. As a result of this study the first “large” tropical dry forest biosphere reserve in Mexico is currently being established. In conclusion, landscape-based conservation zoning based on local stakeholders' perspectives as well as on critical biodiversity indicators, proved to be effective for achieving science-based and politically acceptable nature conservation schemes.

Chromosome evolution (including polyploidy, dysploidy, and structural changes) as well as hybridization and introgression are recognized as important aspects in plant speciation. A suitable group for investigating the evolutionary role of chromosome number changes and reticulation is the medium-sized genus Melampodium (Millerieae, Asteraceae), which contains several chromosome base numbers (x = 9, 10, 11, 12, 14) and a number of polyploid species, including putative allopolyploids. A molecular phylogenetic analysis employing both nuclear (ITS) and plastid (matK) DNA sequences, and including all species of the genus, suggests that chromosome base numbers are predictive of evolutionary lineages within Melampodium. Dysploidy, therefore, has clearly been important during evolution of the group. Reticulate evolution is evident with allopolyploids, which prevail over autopolyploids and several of which are confirmed here for the first time, and also (but less often) on the diploid level. Within sect. Melampodium, the complex pattern of bifurcating phylogenetic structure among diploid taxa overlain by reticulate relationships from allopolyploids has non-trivial implications for intrasectional classification.

Several studies have proposed a group of morpho-functional traits as determinants of the ecological strategy of species. Among these, four morpho-functional traits are considered to be relevant in determining a plant’s ecological strategy: specific leaf area (SLA), height at maturity (Hmax), wood density (WD), and seed mass (SM). We examined the variation of these traits and attempted to identify functional groups among 33 tree species with different biogeographical affinities from a montane cloud forest. Covariation among the four traits was examined using Principal Component Analysis (PCA) and species clustering. Bivariate trait relationships were evaluated through two methods: cross-species correlations, and evolutionary divergence correlations using phylogenetically independent contrasts (PICs). Correlations between attributes were overall weak, the most obvious ones being between Hmax and SM, and between Hmax and WD; this latter trait pair was also correlated in PICs. In both analyses SLA was unrelated to all other traits. In the PCA ordination the first two axes explained 66.9% of the between-species variation. Despite a largely continuous between-species variation, species clustering allowed differentiation of two main groups. Observed trait correlations were consistent with those reported for other floras, with the important exception of the independent behaviour of SLA. This study indicates a variety of comparable successful life history strategies among the studied species. The effect of phylogeny in trait covariation was unimportant, in fact, a mixture of clades was represented in several groups among the species they contained, suggesting among-lineage convergence.

The new eremophilanolide 1 , the known eremophilane derivatives 2 and 3 , already described as part of mixtures, the known compounds hyperin, 2″-acetylhyperin and two calenduladiol esters were isolated from Roldana lineolata . Their structures were determined by spectroscopic methods. Compounds 1 and 2 as well as their acetylated and oxidized derivatives were tested against several fungi strains. Eremophilanolide 1 showed a mild activity against Trichophyton mentagrophytes .

We describe the design and performance of a hybrid extensive air shower detector array built on the Campus of the University of Puebla ( 19 ∘ N , 90 ∘ W , 800 g / cm 2 ) to measure the energy, arrival direction and composition of primary cosmic rays with energies around 1 PeV, i.e., around the knee of the cosmic ray spectrum. The array consists of 3 water Cherenkov detectors of 1.86 m 2 cross-section and 12 liquid scintillator detectors of 1 m 2 distributed in a square grid with a detector spacing of 20 m over an area of 4000 m 2 . We discuss the calibration and stability of the array for both sets of detectors and report on preliminary measurements and reconstruction of the lateral distributions for the electromagnetic (EM) and muonic components of extensive air showers. We also discuss how the hybrid character of the array can be used to measure mass composition of the primary cosmic rays by estimating the relative contents of muons with respect to the EM component of extensive air showers. This facility is also used to train students interested in the field of cosmic rays.

Intrusive and extrusive igneous stones are natural sources of aggregates in volcanic regions. This article describes the mechanical properties of concrete elaborated with these two types of coarse aggregates. Portland cement Type I was used to prepare four different admixtures: two with crushed intrusive volcanic gravel, one with and the other without accelerating additive; and two with extrusive volcanic gravel, one with and the other without superplasticizer additive. The four admixtures, cured on a saturated bed of sand, had a slump of 100 mm. Tests of compressive strength, splitting tensile strength, modulus of rupture and dynamical elastic modulus were performed on the concrete specimens at ages of 3, 7, 14, 21, 28 and 45 days. All of these concretes proved to possess excellent mechanical behavior. This is important because it means that it is possible to lower the overall cost of concrete by using cheap and abundant aggregates.

Fourteen species of Aphyllophorales (Basidiomycotina) were tested for the presence of dyes. The species with the greatest dye potential was Phaeolus schweinitzii , from which five colours, all of excellent intensity, were obtained.

were extracted withMeOHuntiltheextractgaveanegativeDragendor!test.Thesolventwasevaporatedtoone-tenthofitsvolume;acidi"edwith2.5%aq.H2SO4(topH1),stirredovernightwith Zn powder (32.0g) at room temperature and "ltered. The acidic "ltrate waswashed with CHCl3, basi"ed with aq. NH3(to pH10), and extracted with CHCl3.The organic solution dried over Na2SO4, was concentrated to yield 4.56g of alkal-oidal extract. This was submitted to consecutive CCs on silica gel (60 GF254Merck,1:15) elutingwith CHCl3}MeOH19: 1, to give retrorsine(1, 60.1mg), mp 209}2113(SegallandDallas,1983),senecionine(2,89.4mg),mp235-73(SegallandDallas,1983),andretrorsinehydrochloride(1zHCl,14.0mg).Thelesspolarfractionswerecombinedandpuri"edbyCCelutedwithhexane-EtOAc9:1a!ordingmethyl

The aerial parts of Perymenium hintonii gave, in addition to known coumarins, flavonoids and triterpenes, two new phytane-type diterpenes named tuxpanolide and isotuxpanolide. Their structures were elucidated by 1D and 2D NMR techniques.

The structure and absolute configuration of the new 13-membered macrocyclic alkaloids mulgediifoline and oxyretroisosenine were determined on the basis of chemical reactions and conventional spectral studies including differential nOe and 2D NMR techniques, COSY, HETCOR, COLOC, HMBC and NOESY. The absolute stereochemistry of the already known compounds retroisosenine and cis -nemorensic acid was assigned unambiguously.