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This paper discusses how narratives in Mexican Sign Language (LSM) have become relevant in two ways: the first is related to the acquisition and development of LSM at early ages; the second responds to the use of picture books as a strategy to bring Deaf children closer to written Spanish, which has given rise to the interpretation and translation of literary works aimed at children; in turn, this demands the adaptation of these texts in order to offer them appropriately to their recipients. This is ongoing research that is part of a research project in which the acquisition of SLM as a first and second language is studied from the perspective of the bilingual/intercultural educational model offered to Deaf students in Mexico. From the analysis of the narratives in LSM that are offered to Deaf children to strengthen their competence in sign language and their literacy in a second language, we recognize the importance of discussing the role of cultural and linguistic mediation of teachers and interpreters, deaf and hearing, for the achievement of these objectives. [ABSTRACT FROM AUTHOR]

Introduction: The increasing presence of plastics in aquatic ecosystems has been considered as an emerging global environmental problem. Studies have shown that microplastics can be ingested by a variety of aquatic organisms. The natural variability and importance of the sardine resource are sufficient reasons to evaluate the presence of these particles in stomach contents, and thus generate information about the ingestion implications of these emerging contaminants. Objective: To evaluate the presence of microplastics in the stomach contents of sardines and their correlation with the physiological and reproductive condition of the fish studied. Methodology: We evaluated a total of 800 sardines between April and May 2022. We measured total length and weight, and determined the condition factor and the gonadosomatic index. We removed the digestive tract and weighed the stomach both empty and full, as well as the stomach contents to determine the repletion and emptiness index. We correlated the determined variables with the abundance of microplastics. We extracted microplastics and characterized them physically. Results: The filling index presented monthly differences with an average of 0.311. The average vacancy index was 0.276. The average abundance of microplastics was 3 066 items, with monthly differences and interaction with respect to sex and a frequency of appearance of 70.125 %, with a total of 2 402 fibers and 57 fragments. Black fibers were the most abundant (947 items). Low and positive correlations were found between the abundance of microplastics, the gonadosomatic index and the weight of the organisms. Conclusions: These results cannot be conclusive as to the consequences caused by this emerging pollutant. Further study is necessary, including laboratory tests with standardized methodologies. [ABSTRACT FROM AUTHOR]

Introduction: The Cedeño Turtle Camp has been the least researched site in the Fonseca Gulf, where Olive Ridley Turtles in Honduras have been protected since 1975. Objective: To evaluate the nesting of Olive Ridley turtles (Lepidochelys olivacea) during the closed season from 2011 to 2021 in Campamento Tortuguero Cedeño, Choluteca, Honduras. Methods: From 2011 to 2021, daily monitoring of nesting activities was conducted during the closed season from the 1st to 25th of September. Patrols were conducted between 6:00-18:00 h, and 18:00-5:00 h. The total number of nesting turtles was recorded, and their eggs were collected and transported to the hatchery, where clutch and hatchling performance were tabulated. Results: A total of 1 065 L. olivacea turtles were recorded, 95 051 eggs collected, 1 065 nests marked on three beaches that were relocated in artificial hatcheries and a successful hatching of 62 747 hatchlings. Las Doradas beach was the site with the highest number of nesting turtles, followed by Los Delgaditos and lastly Cedeño. The average nesting frequency was 96 nests. From 2011 to 2021 the nest collection effort increased by 91.6 %, from 84 to 161 nests. The number of people patrolling was associated with the number of nests detected on the beaches. Conclusion: Monitoring and conservation efforts for L. olivacea in the Campamento Tortuguero Cedeño show a positive trend in nesting with a greater increase in Playa Las Doradas. This scenario proves the functionality of the closed season in this area. [ABSTRACT FROM AUTHOR]

Introduction: We know of no studies on the microsporogenesis of the cocoa plant, and little is known about the ultrastructure of its pollen grains. Objective: To describe microsporogenesis and ultrastructure of pollen grains in T. cacao. Methods: We processed over 30 flowers for each floral stage and stained with Safranin-Alcian Blue, PASAmidoblack and Lacmoid. For transmission microscopy we processed samples on resin and stained with toluidine blue. For scanning electron microscopy, we fixed and dehydrated in 2.2-dimethoxypropane, critically dried and coated with gold. Results: Anthers differentiated by a cellular mass at the ends distal to the staminal filaments. During development, the anther wall has several cellular layers reduced, at maturity, to the epidermis and endothecium. Microspore mother cells divide by meiosis to form tetrads. The tapetum is secretory and intact until the grains are released, to later degenerate. Pollen grains are isopolar, spheroidal, small, tricolpate. Ultrastructure has a semi-tectate sporodermis, with reticulate ornamentation, and heterobrochated reticulum with the muri without ornamentation. Exine is deposited before intine. The orbicles are individual, smooth, and varied in size. There is abundant pollenkitt on the tectum and between the columellae. The intine is thin, but develops widely in the colpus areas, forming a compact internal intine and an unusual external intine with a columellated appearance. Conclusion: Anther structure and development follows the angiosperm pattern. Simultaneous microsporogenesis and centripetal deposition of the sporodermis are known from Malvaceae, but intine characters are novel for the family. [ABSTRACT FROM AUTHOR]

This article aims to show some results of the development of extractive production and environmental conflict in two provinces of Costa Rica. Most of the analyzed conflicts were caused by residual contamination from extractive units. In most cases, the local judicial system has not been able to provide solutions to conflicts. [ABSTRACT FROM AUTHOR]

Introduction: Dendrochronological studies in Mexico have been mainly based on conifers, while hardwood species have been little studied. This has been the case of the genus Quercus, which has a high taxonomic diversity in the country but has not been previously studied for dendrochronological issues, despite the ecological and economic values of oak species. Objective: In the present investigation, the dendroclimatic potential of Quercus sideroxyla in Northwestern Mexico was determined, as well as its relationship with climatic variables such as precipitation and temperature. Methods: The research was carried out in the state of Durango, Chavarría Viejo with coordinates (23°43' N & -105°33' W). Samples of 5 cm to 7cm were collected in two sites under forest exploitation and processed by conventional dendrochronological techniques. Results: A chronology of total ring width was developed, which was composed of 30 samples from 16 trees for the period from 1917 to 2018 (101 years). Inter-series intercorrelation values of 0.43, mean sensitivity of 0.36, signal-to-noise ratio of 3.53 and first-order autocorrelation (0.58) were obtained. Regarding the climate-growth relationship, the ring width index values were correlated with data from the climatic station nearest to the study site, where winter-spring precipitation (January-May) was the variable with the greatest influence on the growth of the species. Conclusions: Based on the dendrochronological parameters, the high potential of the species that were used in dendroclimatic studies in the region has demonstrated that the response of the species to precipitation is similar to that of the conifers with which the Quercus sideroxyla shares its habitat with. [ABSTRACT FROM AUTHOR]

Introduction: Studies on microsporogenesis, micromorphology and structure of pollen grains in Malvaceae are scarce. Objectives: To describe the process of microsporogenesis and micromorphological aspects of pollen grains in A. rosea. Methods: Androphores were processed according to standard protocols for sectioning in paraffin. The obtained sections were stained with Safranin-Alcian blue, Aniline blue was used for immature and unfixed anthers and for resin sections of the androphores, Toluidine blue. Ultrathin sections were observed with transmission electron microscopy. For observation with scanning electron microscopy the material was fixed and dehydrated in 2.2 dimethoxypropane, dried to a critical point and coated with gold. Results: Anthers differentiate from a cell mass at the distal ends of the stamen filaments. The wall of the mature anther presents an outer layer of epidermal cells and an inner layer, the endothecium. Microspore mother cells divide by mitosis and then undergo meiosis to form tetrads. The tapetum is initially cellular and forms a single layer of cells and then loses cellular integrity by invading the microsporangium locule, forming a periplasmodia, by the time the pollen grains are released it degenerated. During sporodermis formation, exine is first deposited and then intine. Pollen grains are pantoporate, apolar, with radial symmetry, spheroidal, with spines, bacula, granules and microgranules. Tectum is perforated with foveolae arranged homogeneously over the whole surface and pollenkit is present. Exine is broad and consists of a thick 3.5 to 4 µm endexine and a thin ektexine (0.6-0.7 µm). The ultrastructure shows columellae forming the infratectum. Capitate glandular unicellular nectariferous trichomes covers the whole surface of the stamen filaments. Conclusions: The structure and development of the anthers follows the known patterns for angiosperms. Simultaneous microsporogenesis and centripetal deposit of the sporodermis have been previously described for Malvaceae. [ABSTRACT FROM AUTHOR]

Introduction: Despite the fact that T. cacao is an important species worldwide for cocoa production, little is known about the micromorphology and structure of anthers and pollen grains. Objectives: To describe and analyze the structure and micromorphology of the anthers and pollen grains of 10 elite genotypes of this important tropical species. Methods: More than 30 anthers of flowers in anthesis were taken of the 10 elite genotypes of T. cacao from the ex situ germplasm bank of the Suiza-Agrosavia Research Center (Rionegro, Santander-Colombia). The anthers with the pollen grains were fixated and processed according to the standard protocols for embedding and sectioning in paraffin. Sections obtained (3 μm thick) were stained with SafraninAlcian blue to discriminate structures with primary and secondary walls and total polyphenols. Additionally, the samples were also stained with the PAS-Amidoblack technique was used to differentiate between structural and reserve polysaccharides as well as proteins. Toluidine blue staining was used for the determination of sporopollenin and polyphenols and finally Alcian blue-PAS-Hematoxylin staining was applied for additional descriptions. Observations were made using photonic microscopy and epifluorescence microscopy. For observation with scanning electron microscopy (SEM) the anthers with the pollen grains were fixed and dehydrated in 2.2 Dimethoxypropane, then desiccated to critical point and finally coated with gold. Results: the anthers are dithecal and supported by a long filament made up of an epidermal stratum, parenchymal tissue, and a vascular bundle. The dehiscence occurs longitudinally through the stomium. The anther wall is made up of a monostratified epidermal layer, followed by a layer of endothecial cells with lignified fibrillar thickenings, cellular remnants of tapetum and abundant orbicules can be seen covering the cavity of the microsporangia. The epidermal and parenchymal tissues of the anthers are abundant in polyphenols. Orbicules are generally spherical, psilated, and these exhibit the same staining and fluorescence reactions as exine from pollen grains. The pollen grains are monades, isopolar, small (16-19µm) with circular amb, spheroidal, tricolpate with medium or short colpi (5-10µm) with sculptured membrane, semitectate, reticulated, heterobrochate, sculptured or non- sculptured walls, with microgranules of different size or scabrate. The statistical analyzes showed that there are significant differences in the size of the pollen grains (P ˂ 0.05). It is observed that the smallest pollen grains are those of the TCS 19 genotype (16.890 µm) and are different from the other genotypes, and among these there are no significant differences. Only two genotypes (SCC 19 and SCA 6) showed pollenkit and only one has perforated walls (SCA 6). Conclusions: The structure and micromorphology of the anthers of T. cacao are similar to those described for other Malvaceae. Likewise, the pollen grains showed variations in size, ornamentation of the sporoderm and the lumen of the reticulum and the presence of pollenkitt. However, no relationship was observed between the micromorphological characters analyzed in the pollen grains and the pollen compatibility models reported for these genotypes. [ABSTRACT FROM AUTHOR]

Introduction: There are few studies concerning the morpho-anatomical and histochemical alterations caused by powdery mildew in H. macrophylla leaves in the scientific literature. Objective: To describe and analyze anatomical and histochemical aspects of this pathosystem. Methods: More than 90 leaves of H. macrophylla (both healthy and infected leaves by powdery mildew) were collected in the nursery El Jardín del Eden, Rionegro, Antioquia, Colombia. To carry out the identification of the mycopathogen, sections were stained with Lactophenol Blue, and contrasted with specialized taxonomic keys. Transverse fragments 1 cm thick were fixed in a mixture of formalin, alcohol, and acetic acid. These were subsequently dehydrated using an ethanol series, clarified in Xylene, and finally embedded in Paraplast plus® to obtain 5 µm sections. Schiff's periodic acid reaction (PAS) was used to detect structural and reserve polysaccharides, Ruthenium Red for pectins, Ponseau S and Lacmoid for callose, ferric chloride for polyphenols, Sudan Black for lipids and Uvitex 2B-Hematoxylin for chitin. The sections were observed using a Nikon 80i eclipse® photon microscope, with Uvitex 2B-Hematoxylin-stained sections examined by epifluorescence using a UV-2A filter. For the observation and description of the samples by scanning electron microscopy, healthy and infected leaves were fixed and dehydrated in 100 % methanol, critical point dried, and coated with gold. Results: H. macrophylla leaves are isobilateral and homobaric, with adaxial and abaxial epidermis of a single cellular layer. The palisade parenchyma consists of a layer of short cells, while the spongy parenchyma forms 6 to 7 cellular layers. All vascular bundles in the leaf blade are closed collaterals. Abundant idioblasts with raphides may be observed in the mesophyll, and starch is the main reserve carbohydrate present in the tissues. The leaves are hypostomatic and exhibit a paracytic pattern of superficial stomata which possess large substomatal cavities. The morphological data observed indicate that the mycopathogen is related to the genus Erysiphe. The epidermal cells affected by the pathogen exhibit thickened walls, granular cytoplasm, and papillae or cell wall appositions in the outer periclinal walls. With the deterioration of the epidermis, the underlying tissues are affected and become necrotic. Histochemical test indicate that infected plants thicken and reinforce their epidermal cell walls with primary wall materials; primarily cutin, pectins, and callose. When stained with Sudan Black, the presence of dark-colored agglomerates in the cytoplasm of epidermal cells may be related to plant defense mechanisms; and those observed in mesophilic cells to the disorganization of membrane systems. Polyphenols accumulate in the cytoplasm of infected epidermal cells. The fungal material present in epidermal tissues was clearly differentiated when stained with fluorochrome to detect chitin. Conclusions: Species of the genus Erysiphe are causative agents of powdery mildew in H. macrophylla. Necrosis of the epidermal cells is observed in response to the mycopathogen, possibly due to hypersensitive response. [ABSTRACT FROM AUTHOR]

Introduction: Research about the ontogeny of sori, sporangia, receptacular paraphyses and sporogenesis of leptosporangiate ferns are scarce in the scientific literature. Objectives: To describe and analyze the ontogeny of sori, sporangia, receptacular paraphyses and sporogenesis of Phymatosorus scolopendria. Methods: Fertile fronds of P. scolopendria were collected in the campus of the Universidad de Antioquia, Medellín, Colombia, during the months March and May (annual rain season) of 2017. The fertile fronds of the samples at different developmental stages were fixed and processed according to the standard protocols for embedding and sectioning in paraffin and resin. Sections of 0.5 μm obtained in resin were stained with Toluidine blue, which differentially stains primary and secondary walls, highlights the cell nucleus and sporopolenin and secondarily stains polyphenols. For detailed descriptions, additional sections were processed with Safranin-Alcian blue, allowing the distinction of components of primary and secondary walls, nuclei, cuticle and polyphenols; Hematoxylin-Alcian blue to enhance nuclei and primary walls and Phloroglucinol-HCl for lignin. Observations and photographic records were done with a photonic microscope. For the observations and descriptions with scanning electron microscopy (SEM), the sori were dehydrated with 2,2-dimethoxypropane, critical point dried and coated with gold. Results: The sori are exindusiate, superficial, vascularized and have mixed development; they are associated with uniseriate and multicellular receptacle paraphyses. During the development of the sori, the epidermal cells of the receptacle that will form the sporangia are the first differentiated followed by those forming the receptacle paraphyses. The sporangium is leptosporangiate, with long stalks formed by one or two cell rows. The annulus of the sporangia displays secondary walls with U-shaped thickenings rich in lignin. The meiosis is simultaneous and the spore tetrads are arranged in a decussate or tetragonal shape. The cellular tapetum is initially unistratified but becomes bistratified after a periclinal division. The cells of the internal strata of the cellular tapetum loose structural integrity giving rise to a plasmodial tapetum that invades the meiotic sporocytes. During the sporoderm development, the sporopollenin-composed exospore is the first formed followed by the endospore, composed by cellulose, pectin and carboxylated polysaccharides; the process ends with the perispore. Polyphenols were mainly detected on vacuoles in cells of the sporangium, paraphysis and receptacle. When the time comes for the spore maturation, the remnants of cellular and the plasmodial tapeta have fully degenerated. Abundant orbicles are seen near the spores in the sporangial cavity. Conclusions: The ontogeny of the sporangia and sporogenesis of P. scolopendria are similar to the previously described for leptosporangiate ferns. Furthermore, in P. scolopendria, the receptacle paraphyses of the sori have a role protecting the sporangium during the early development stages. [ABSTRACT FROM AUTHOR]

Introduction: Histopathological and histochemical aspects linked to the attack of fungal rusts to plants, as well as its relation with the different spore stages are topics rather scarce in the scientific literature. Objective: To describe and analyze the histopathological and histochemical aspects of Cymbopogon citratus and its relation with the different stages of the spores from the rust fungi Puccinia nakanishikii. Methods: During the months April and August 2013, leaves healthy and infected by Puccinia nakanishikii were collected in the Northwestern scarp of the Bucaramanga-Colombia plateau. The samples with injuries on diverse developmental stages were fixated and processed according to the standard protocols for embedding and sectioning in paraffin and resin. Sections obtained from paraffin (5-7 μm) were stained with Safranin-Alcian blue and Alcian blue-Hematoxylin. On the other hand, sections obtained from resin (0.5 μm) were stained with Toluidine blue. Further, freehand sections were obtained for an autofluorescence analysis. The observations and photographic record were done via photonic microscope and epifluorescence microscope. For the observations via scanning electron microscopy (SEM), the samples were fixated in Glutaraldehyde, dehydrated with 2,2 dimethoxypropane, then desiccated to critical point and finally coated with gold. Results: The leaves are generally hypostomatic, with long and short epidermic cell forming parallel rows and showing unicellular prickle trichomes and micro-trichomes. The abaxial surface is covered by epicuticular wax forming a dense layer. The adaxial epidermis is formed by groupings of bulliform cells and epidermal cells with rectangular or squared contour. In the mesophyll, there is no differentiation between palisade and spongy parenchyma, its anatomy reflects the C4 metabolism. The formation of uredosori and teliosori both hypophyllous was observed. Urediniospores are the reinfecting agents phase, they have 4-5 equatorial germ pores and echinulate wall. Teliospores have smooth wall and a persistent pedicel. The urediniospores form a germ tube, generally on the abaxial leaf surface, these tubes develop towards the stomata reaching the mesophyll interior. No appressorium were observed. The epidermis limiting the uredosorus detaches due the development and pressure that exert both the urediniospores and capitate paraphyses. As the infection progresses, autofluorescense of the chlorophyll is lost and the cells undergo necrotic processes. Afterwards, the phloem collapses and the xylem becomes slightly disorganized. At this moment, the infection is extended along the whole leaf blade, resulting in the leaf death and the plant defoliation. On advanced stages of the infection, the uredosori showed pycnidia, probably belonging to the hyperparasite Sphaerellopsis, these structures were closely associated to the rust infected tissues. Conclusions: Puccinia nakanishikii develops on the leaves of Cymbopogon citratus producing uredosori and teliosori. Urediniospores are the reinfective stage, teliospores were only observed at late stages of the infection. The epidermis and photosynthetic tissue are severely affected by cell necrosis. The vascular tissues are deeply affected on the advances stages of the infection. [ABSTRACT FROM AUTHOR]

In many instances, crisis drive changes that mark societal evolution. This has applied to naturesociety relationships by the analysis whereby crises determine this type of relationships and viceversa. This essay examines some possible avenues of action, motivated by the COVID-19 pandemic, towards more resilient and sustainable societies. Furthermore, it briefly examines the relationship between infectious diseases and human environmental actions, as well as some initiatives that are being promoted to engender social changes towards sustainability. [ABSTRACT FROM AUTHOR]

Introduction: The ontogeny of sporangia and furthermore the structure and function of the receptacle scales showed by the sori of some fern species are topics scarcely represented in the scientific literature. Objectives: To describe and analyze the ontogeny of sporangia and receptacle scales of Pleopeltis macrocarpa. Methods: During March and April of 2017, fertile fronds of P. macrocarpa were collected from tree stems located in the plant nursery “El Edén de las flores", municipality of Rionegro, Antioquia, Colombia. The samples were fixed and processed according to the standard protocols for embedding and sectioning in paraffin and resin. Sections obtained in resin (0.5 μm) were stained with Toluidine blue. The additional descriptions of the anatomy and histochemistry required specific reagents, applied for the determination of primary walls, secondary walls, nuclei, lignin, polyphenols, polysaccharides, pectic substances and cellulose. The observations and photographic records were performed by photonic and epifluorescence microscopy. For the scanning electron microscopy (SEM) technique, the sori were dehydrated with 2,2- Dimethoxypropane, dried to critical point and coated with gold. Results: The sori are superficial, vascularized and have mixed development, covered by receptacle scales that detach as the sporangia reaches maturity. The leptosporangiate type sporangium have long stalks of primary walls, the annulus of the sporangia shows secondary walls with “U" shaped thickenings rich in lignin. The epidermal cells of the receptacle originate the sporangia and receptacle scales. The mitotic division events of these two structures are initially similar, but then diverge for the reproductive and vegetative differentiation of these two organs. Meiosis is simultaneous and the spore tetrads are arranged in a decussate or tetragonal shape. The cellular tapetum is initially unstratified but becomes bistratified by mitotic division. The inner layer of the tapetum cells break originating a plasmodial tapetum. During the sporoderm development, the first structure formed is the exospore, composed of sporopolenin, followed by the endospore composed of cellulose, pectin and carboxilated polysaccharides, and finally the perispore. The histochemistry and epifluorescence results indicate that both the sporangia and immature receptacle scales have cell walls of cellulosic. These structures as well as those of the sporangium wall cells maintain its composition during maturation. Whereas, the epidermal wall cells of the shields from the mature receptacle scales are characterized by thickened cuticle. The polyphenols are present during all the development stages of the sporangia and receptacle scales. Starch is abundant in the early stages of development of the receptacle cells and sporangial primordia. Conclusions: The ontogeny of the sporangia of P. macrocarpa is similar to the described for leptosporangiate ferns. The receptacle scales are mainly protective structures, its morphology and cell wall composition prevent desiccation or humidity loss of the sporangia during the labile stages of development. These results agree with the protective function attributed to the peltated pluricellular scales present in the vegetative structures of drought tolerant species of ferns and angiosperms. [ABSTRACT FROM AUTHOR]

For the control of Rhipicephalus microplus, cattle tick, pyrethroid compounds are used among others. The study of the mechanisms of resistance to pyrethroids in this tick has shown the presence of mutations in the sodium channel gen, the target site of acaricide. The main objective of the present study was to detect the T2134A polymorphism in the sodium channel gene that has been related to pyrethroid resistance in carriers. To do so, 182 ticks R. microplus were collected in two farms with a history of resistance to this type of acaricide and were subjected to a dip test of females in a cypermethrin solution prepared at the recommended dose for field use, obtaining six susceptible, 92 resistants and 84 moderately resistants. DNA is extracted from all specimens using QIAamp DNA Mini Kit® and processed by conventional PCR using allelespecific primers to amplify a segment of domain IIIS6 of the sodium channel gene. The resulting amplicons were detected by electrophoresis in 2 % agarose gels stained with GelRed® and visualized with ultraviolet light. In the same way, 20 samples were sequenced of the three susceptible phenotypes, moderately resistant and resistant and the resulting sequences were aligned through the Mega 7 program and compared with the sequences stored in the GenBank®. The information of the population of R. Microplus studied did not show the expected mutation but a different mutation in the site 2134. We also observed the substitution of a thymine but by a cytosine, T2134C, which changes to a phenylalanine by a leucine, a difference from the previously identified mutation, that the change from phenylalanine to isoleucine. This shows the presence of a polymorphism that has not been reported in this species of tick and that would generate a new molecular marker of pyrethroid resistance for populations of this mite. [ABSTRACT FROM AUTHOR]

This article evidences that local productive system in Atlantic/Caribbean region in Costa Rica, based on banana and pineapple plantations for export, is responsible of severe damage to nature and could not resolve social problems like poverty. This conclusion is based on analysis of numerous scientific and technical literatures about environmental and social effects of productive activities in Atlantic/Caribbean region, between 1990 and 2015. This situation contradicts the objectives of Sustainable Development model established in Costa Rica, aimed at protection of nature and resolving needs of people. [ABSTRACT FROM AUTHOR]

The longitudinally analysis about official data and governmental plans and actions for Chorotega region´s development, including what governments promised and materialized, has demonstrated the successful region´s integration process to national economic and social model in the study period. Thus, this territory had received important public investment in social services and productive infrastructure that built main projects in tourism and agriculture areas, but is had been not enough to resolve traditional social problems like unemployment and poverty. [ABSTRACT FROM AUTHOR]

In Charophyceae, the oosporangia and antheridia are the respective female and male structures of sexual reproduction. These organs are characterized by their morphological complexity and usefulness in taxonomy and systematics. Here we described the structural and ultraestructural details of Chara hydropitys gametogenesis. The fertile material from the algae was collected in a tributary stream of the Río Meléndez in Cali, Colombia (3°21'23'N - 76°32'5.2''W) in March 2011. The specimens were fixed and processed following the standard protocols for inclusion in resin. Thin sections (0.3-0.5 μm) were stained with toluidine O and were observed by photonic microscopy and additional ultrathin sections (60-90 nm) were observed by transmission electron microscopy (TEM); other samples were processed and observed by scanning electron microscopy (SEM). We found that the oosporangia are covered with spiral cells, forming 10-12 convolutions and ends in five coronula cells. The immature oosporangia wall is formed by two layers that correspond to the wall of the spiral cells and to the oosphere. In mature stages, the oosporangia wall is composed by six additional layers, three of them are provided by the oosphere and the other three are provided by the spiral cells. Oosphere size increases progressively while the spiral cells grow and divide. The cytoplasm of the immature oosphere does not exhibit conspicuous cytoplasmic inclusions, nevertheless, with the maturation, the number of starch granules increases, occupying most of the cell volume. In the spiral cells of the mature oosporangia we observed large number of chloroplast with starch accumulations, between thylakoid lamellae and a vacuole that occupies almost the entire cell. By using SEM it was possible to appreciate, that the external wall of the oospore, more accurately, on the fossa area, shows verrucose micro-ornamentations with verrucae elevations. In mature antheridia, shield cells are strongly pigmented orange due to the presence of a large number of plastoglobules between thylakoid lamellae. The spermatogenous filaments are developed from cells of the secondary capitulum; those, by unidirectional and sincronic mitotic divisions develop the spermatocytes. The biflagellate antherozoids are developed from the haploid cells by spermiogenesis. The subcellular events related with these division and differentiation processes, include first, chromatin condensation, loss of nucleoli and more activity in dictyosomes. Subsequently, retracts the cytoplasm and the organelles are aligned along the condensed nucleus and flagellar apparatus. Mature antherozoids emerge through a side wall pore of the spermatocytes. All the described events showed that the gametogenesis processes and the gametes structural details in general, are widely conserved in this algae group. [ABSTRACT FROM AUTHOR]

The aim of the article is to follow a historical conception of regional integration contained in the constitutions of Central America between 1952 (OCAS) and 1986 (Esquipulas I and ii). The comparison of the notion of integration to which it aspires each Central American nation and that is reflected in its constitutional texts is made. It is concluded that at the beginning of the XXI century, Central America is a region with integrated societies but not amalgamated. [ABSTRACT FROM AUTHOR]

This article identifies the main social and environmental results derived from tourism development in Guanacaste's coasts, through the analysis of theoretical, scientific and statistical data, as well as information collected through interviews with local activists. It is considered that tourism development is guilty of intensive appropriation of nature and overexploitation of the aquifers that supply local communities, as well, the emergence of social movements against developers and government, to control access to environmental resources considered basics to subsistence. [ABSTRACT FROM AUTHOR]

During the second half of the twentieth century, the state settled the Chorotega region's isolation from the rest of the country through the construction of modern land routes and the establishment of dynamic production systems. However, this process of modernization and technological change failed to reverse the serious social problems such as poverty, unemployment and inequality. [ABSTRACT FROM AUTHOR]

Wild specimens of Vanilla planifolia represent a vital part of this resource primary gene pool, and some plants have only been reported in Oaxaca, Mexico. For this reason, we studied its geographical distribution within the state, to locate and describe the ecological characteristics of the areas where they have been found, in order to identify potential areas of establishment. The method comprised four stages: 1) the creation of a database with herbarium records, 2) the construction of the potential distribution based on historical herbarium records for the species, using the model of maximum entropy (MaxEnt) and 22 bioclimatic variables as predictors; 3) an in situ systematic search of individuals, based on herbarium records and areas of potential distribution in 24 municipalities, to determine the habitat current situation and distribution; 4) the description of the environmental factors of potential ecological niches generated by MaxEnt. A review of herbarium collections revealed a total of 18 records of V. planifolia between 1939 and 1998. The systematic search located 28 plants distributed in 12 sites in 95 364 Km2. The most important variables that determined the model of vanilla potential distribution were: precipitation in the rainy season (61.9 %), soil moisture regime (23.4 %) and precipitation during the four months of highest rainfall (8.1 %). The species potential habitat was found to be distributed in four zones: wet tropics of the Gulf of Mexico, humid temperate, humid tropical, and humid temperate in the Pacific. Precipitation oscillated within the annual ranges of 2 500 to 4 000 mm, with summer rains, and winter precipitation as 5 to 10 % of the total. The moisture regime and predominating climate were udic type I (330 to 365 days of moisture) and hot humid (Am/A(C) m). The plants were located at altitudes of 200 to 1 190 masl, on rough hillsides that generally make up the foothills of mountain systems, with altitudes of 1 300 to 2 500 masl. In natural conditions, distribution of the species is not limited to high evergreen forests, since it was also found in mountain mesophyll and tropical evergreen forests. The location of new specimens of V. planifolia in its wild condition reduces the potential distribution area by 66 %. This area is fragmented into three geographically separated areas. Habitat reduction was due to the increased number of located plants that define the environmental conditions into a more accurate level. Conservation actions can thus be designed and implemented, focusing on more specific areas within the state of Oaxaca, Mexico. [ABSTRACT FROM AUTHOR]

Studies on reproductive aspects, spore morphology and ultrastructure of Lycopodiaceae are not very common in the scientific literature, and constitute essential information to support taxonomic and systematic relationships among the group. In order to complete existing information, adding new and broader contributions on these topics, a comparative analysis of the sporogenesis ultrastructure, with emphasis on cytological aspects of the sporocyte coat development, tapetum, monoplastidic and polyplastidic meiosis, sporoderm ontogeny and ornamentation of the mature spores, was carried out in 43 taxa of eight genera of the Lycopodiaceae: Austrolycopodium, Diphasium, Diphasiastrum, Huperzia (including Phlegmariurus), Lycopodium, Lycopodiella, Palhinhaea and Pseudolycopodiella growing in the Andes of Colombia and the Neotropics. For this study, the transmission electron microscopy (TEM) samples were collected in Cauca and Valle del Cauca Departments, while most of the spores for scanning electron microscopy (SEM) analysis were obtained from herbarium samples. We followed standard preparation procedures for spore observation by TEM and SEM. Results showed that the sporocyte coat is largely composed by primary wall components; the sporocyte develop much of their metabolic activity in the production of their coat, which is retained until the spores release; protective functions for the diploid cells undergoing meiosis is postulated here for this layer. The abundance of dictyosomes in the sporocyte cytoplasm was related to the formation and development of the sporocyte coat. Besides microtubule activity, the membrane of sporocyte folds, associated with electrodense material, and would early determine the final patterns of spore ornamentation. Monoplastidic condition is common in Lycopodium s.l., whereas polyplastidic condition was observed in species of Huperzia and Lycopodiella s. l.. In monoplastidic species, the tapetum presents abundant multivesicular bodies, while in polyplastidic species, the secretory activity of the tapetum is less intense. Sporoderm development is centripetal, exospore is the first formed layer, then the endospore and, if present, perispore is the final deposited layer. Adult spores of the Lycopodiaceae showed two patterns of ornamentation: negative or caviform (foveolate spores) and positive or muriform ornamentation, the latter with two subtypes (rugate and reticulate spores). The spores of Huperzia are characteristically foveolate, the rugate spores were found in a few species of Huperzia and in all of the Lycopodiella s. l. taxa studied, while Lycopodium s.l. spores bear reticulate ornamentation. Numerous ornamentation traits are diagnostic at the specific level. The types of ornamentation found do not support the recent extreme fragmentation of the family in several genera, but could match, a priori, with the idea of three subfamilies. The findings of sporogenesis, extremely similar in all taxa studied, point more to consider fewer genera, more comprehensive, than the recent, marked splitting of the family. [ABSTRACT FROM AUTHOR]

El artículo discurre sobre la obra de la filósofa española Esperanza Guisán acerca del utilitarianismo y la ética. El autor comenta sobre la capacidad humana de ser moral, según Guisán, y describe la relación entre la ética y la razón y la pasión. También se considera los aspectos filosóficos de la condición humana, incluyendo la felicidad y la bondad.

(Lycopodiaceae). Studies on reproductive aspects of Lycopodiaceae are not very abundant in the scientific literature, and constitute essential information to support taxonomic and systematic relationships among the group. Here we present a detailed study of the ontogeny of sporangia and sporogenesis, and the chemical determination of several compounds generated during spore formation. The analyses were performed in 14 taxa of six genera of the family, Diphasiastrum, Diphasium, Huperzia (a genus which is treated here including Phlegmariurus), Lycopodiella, Lycopodium and Palhinhaea. Specimens were collected in three departments from the Colombian Andes between 1 454-3 677m altitude. Ontogeny was studied in small, 1cm long pieces of strobili and axis, which were fixed in glutaraldehyde or FAA, dehydrated in alcohol, embedded in LR White, sectioned in 0.2-0.5μm and stained with toluidine blue (TBO), a metachromatic dye that allows to detect both sporopollenin and lignin or its precursors, during these processes. For other studies, paraplast plus-embedded sections (3-5μm) were stained with safranin-fast green and alcian blue-hematoxylin. Chemical tests were also conducted in sections of fresh sporangia at different stages of maturity using alcian blue (mucopolysaccharides), Lugol solution (starch), Sudan III (lipids), phloroglucinol (lignin) and orcein (chromosomes). Sections were observed with photonic microscope equipped with differential interference contrast (DIC) and fluorescence microscopy (for spore and sporangium walls unstained). Strobili and sporangia were dehydrated with 2.2 dimethoxypropane, critical point dried and coated with gold for scanning electron microscopy (SEM). Our results indicated that the ontogeny of sporangia and sporogenesis were very similar to the previously observed in Huperzia brevifolia. Cutinisation occurs in early stages of development of sporangium cell walls, but in their final stages walls become lignified. As for the sporoderm development, the exospore is the first layer formed, composed by sporopollenin. The endospore deposits as a thin inner layer composed of cellulose, pectin and carboxylated polysaccharides. The perispore, if present, deposits at last. Mucopolysaccharides were found on the sporocyte coat and its abundance in sporangial cavity persists up to the immature tetrads stage, and then disappears. The lipids were abundant in the sporocytes, tetrads and spores, representing the main source of energy of the latter. In contrast, starch is not detected in the spores, but is abundant in premeiotic sporocytes and immature tetrads, developmental stages of high cellular metabolic activity. Intrinsic fluorescence corroborates the presence of lignin and cutin in the sporangium wall, while the sporopollenin is restricted to the exospore. The transfusion cells and the perispore are not always present. However, the processes of ontogeny and sporogenesis are extremely similar throughout the taxa studied, suggesting that they represent conservative family traits, nonspecific or generic. [ABSTRACT FROM AUTHOR]

Studies on some reproductive traits in Equisetum species are scarce and valuable to understand species distribution. Therefore, a detailed study of the sporogenesis process and spore development in E. bogotense is presented, with an analysis of the main events during meiosis, maturation of spores, spore wall ultrastructure, orbicules and elaters. Specimens were collected from 500 to 4 500m in Cauca, Colombia. Strobili at different maturation stages were fixed, dehydrated, embedded in resin, and ultra-microtome obtained sections were stained with Toluidine blue. Observations were made with optical microscopy with differential interference contrast illumination technique (DIC), transmission and scanning electron microscopy (TEM and SEM). Ultrathin sections (70-80µm) for TEM observations were stained with uranyl acetate and lead citrate; while samples for SEM observations, were fixed, dehydrated in 2.2-dimethoxypropane and dried at critical point as in standard methods. Strobili have numerous mature sporangiophores, each one with a peltate structure, the scutellum, bearing five-six sessile sporangia attached to the axis of strobilus by the manubrium. Immature sporocytes (spore mother cells) are tightly packed within the young sporangia. The sporocytes quickly undergo meiosis, by passing the stage of archesporium and give origin to tetrads of spores. The tapetum loses histological integrity during early stages of sporogenesis, intrudes as a plasmodial mass into the cavity of the sporangium, partially surrounding premeiotic sporocytes, and then, tetrads and adult spores. The tapetum disintegrates towards the end of the sporogenesis, leaving spores free within the sporangial cavity. Spores present several cytological changes that allow them to achieve greater size and increase the number of plastids, before reaching the adult stage. Sporoderm includes three layers external to the cytoplasmic membrane of the spore cell, and they are pseudoendospore, exospore and perispore. Viewed with SEM, the exospore is smooth to rugulate, with micro perforations, while the perispore is muriform, rugate, with narrow, delicate, discontinuous, randomly distributed folds delimiting incomplete, irregular areolae, externally covered by of different size, densely distributed orbicules. These orbicules are also found all over the external face and margins of the elaters, while the internal face is smooth and lack orbicules. Viewed with TEM, the exospore is a thick layer of fine granular material, while perispore is a thinner layer of dense, separate orbicules. The elaters are composed by two layers of fibrillar material: an inner layer with longitudinally oriented fibrils and an outer, thicker and less dense layer with fibrils transversely fibrils and abundant, external orbicules. It is suggested that the processes of ontogeny and characters of the sporoderm are relatively constant in Equisetum; however, sporogenesis in E. bogotense is synchronous and this condition has been observed so far only in E. giganteum, a tropical genus also found in Colombia. [ABSTRACT FROM AUTHOR]

Studies on the ontogeny of the strobilus, sporangium and reproductive biology of this group of ferns are scarce. Here we describe the ontogeny of the strobilus and sporangia, and the process of sporogenesis using specimens of E. giganteum from Colombia collected along the Rio Frio, Distrito de Sevilla, Piedecuesta, Santander, at 2 200m altitude. The strobili in different stages of development were fixed, dehydrated, embedded in paraffin, sectioned using a rotatory microtome and stained with the safranin O and fast green technique. Observations were made using differential interference contrast microscopy (DIC) or Nomarski microscopy, an optical microscopy illumination technique that enhances the contrast in unstained, transparent. Strobili arise and begin to develop in the apical meristems of the main axis and lateral branches, with no significant differences in the ontogeny of strobili of one or other axis. Successive processes of cell division and differentiation lead to the growth of the strobilus and the formation of sporangiophores. These are formed by the scutellum, the manubrium or pedicel-like, basal part of the sporangiophore, and initial cells of sporangium, which differentiate to form the sporangium wall, the sporocytes and the tapetum. There is not formation of a characteristic arquesporium, as sporocytes quickly undergo meiosis originating tetrads of spores. The tapetum retains its histological integrity, but subsequently the cell walls break down and form a plasmodium that invades the sporangial cavity, partially surrounding the tetrads, and then the spores. Towards the end of the sporogenesis the tapetum disintegrates leaving spores with elaters free within the sporangial cavity. Two layers finally form the sporangium wall: the sporangium wall itself, with thickened, lignified cell walls and an underlying pyknotic layer. The mature spores are chlorofilous, morphologically similar and have exospore, a thin perispore and two elaters. This study of the ontogeny of the spore-producing structures and spores is the first contribution of this type for a tropical species of the genus. Fluorescence microscopy indicates that elaters and the wall of the sporangium are autofluorescent, while other structures induced fluorescence emitted by the fluorescent dye safranin O. The results were also discussed in relation to what is known so far for other species of Equisetum, suggesting that ontogenetic processes and structure of characters sporoderm are relatively constant in Equisetum, which implies important diagnostic value in the taxonomy of the group. [ABSTRACT FROM AUTHOR]

Alexander F. Skutch published six papers in La Revista de Filosofía de la Universidad de Costa Rica. This paper focuses mainly on important ethical concepts and the criticism of humanism present therein. [ABSTRACT FROM AUTHOR]

Huperzia brevifolia is one of the dominant species of the genus Huperzia living in paramos and superparamos from the Colombian Andes. A detailed study of the sporangium's ontogeny and sporogenesis was carried out using specimens collected at 4200m above sea level, in Parque Natural Nacional El Cocuy, Colombia. Small pieces of caulinar axis bearing sporangia were fixed, dehydrated, paraffin embedded, sectioned in a rotatory microtome, and stained using the common Safranin O-Fast Green technique; handmade cross sections were also made, stained with aqueous Toluidine Blue (TBO). The sporangia develops basipetally, a condition that allows observation of all the developmental stages taking place throughout the caulinar axis of adult plants. Each sporangium originates from a group of epidermal cells, axilar to the microphylls. These cells undergo active mitosis, and produce new external and internal cellular groups. The sporangium wall and the tapetum originate from the external group of cells, while the internal cellular group leads to the sporogenous tissue. Meiosis occur in the sporocytes and produce simultaneous types tetrads, each one giving rise four trilete spores, with foveolate ornamentation. During the sporangium ripening, the outermost layer of the wall develops anticlinally, and inner periclinal thickenings and the innermost one perform as a secretory tapetum, which persists until the spores are completely mature. All other cellular layers colapse. Rev. Biol. Trop. 57 (4): 1141-1152. Epub 2009 December 01. [ABSTRACT FROM AUTHOR]

Thomas Harriot (England) and Galileo Galilei (Venice) made telescopic observations and drawings of the lunar relief. Although Harriot preceded the Florentine philosopher, Galileo, by means of Renaissance's pictorial perspective could interpret his perceptions in a way significant to produce the suitable material to overthrow the peripatetic conception of our satellite. [ABSTRACT FROM AUTHOR]

The article analyzes the formation of the Central American political regional community in the beginnings of the XX century. It is emphasized in the study of the process of Central American political integration starting from the Treaty of Corinth of 1902 and the later subscription of the Treaty of Peace, friendship and Trade of 1906, undersigned in San José, Costa Rica. The central concept of the article is that of political community, from which is approached the Central American regional socio-political dynamics and its relationship with the processes of regional integration. [ABSTRACT FROM AUTHOR]

Temporal and spatial distribution of ants in a light gradient, in a coffee agroforestry system, Turrialba, Costa Rica. Shade trees are frequently present in coffee (Coffea arabica L.) agroforestry systems of Mesoamerica. These systems can harbor a rich entomofauna, including ants, which could be predators of key pests in these systems. However, the role of shade on the distribution and abundance of these ants is unknown, yet such knowledge could suggest guidelines for manipulating certain environmental conditions of their habitat, thereby achieving their conservation and increase. Therefore, we studied the effect of shade on the spatial and temporal distribution of three ant species (Solenopsis geminata, Pheidole radoszkowskii and Crematogaster curvispinosa) that may prey on the coffee berry borer, Hypothenemus hampei (Coleoptera: Scolytidae), and the mahogany shootborer, Hypsipyla grandella (Lepidoptera: Pyralidae). To do this, abundance was evaluated across a sun-shade gradient in a coffee plantation with four alternate plots (from pure sun to total shade) in Turrialba, Costa Rica. In the community that was studied 28 species of ants were collected, of which S. geminata was the dominant species (79 % of the total individuals), followed by P. radoszkowskii (16 %). S. geminata and C. curvispinosa preferred sunny areas, while P. radoszkowskii showed no defined preference. Likewise, with respect to location, S. geminata predominated in the soil, while P. radoszkowskii and C. curvispinosa predominated in coffee bushes. [ABSTRACT FROM AUTHOR]

With the intention to approximate an assessment of quality of life of inhabitants in our country, indices were developed from continuous statistics, for the period 1990 to 2003. Two aggregation methods were utilized to obtain annual marks for the indices. Beyond the global score for quality of life, scores for each dimension used in developing the index were obtained. These indices are just a proposal because of the lack of data availability and peer discussions on this subject. Nevertheless, results allow seeing that from 1990 to 2003, quality of life has reached medium levels with a trend to deterioration. [ABSTRACT FROM AUTHOR]

The article presents a historical pursuit of how environmental education has suffered and of how this has moved from the 1980s to the 20th century including tendencies related to sustainable development. The transformation is analyzed focusing on the suffering of nature and the notion of "object," modeled from the XVIII century Emilio of Rousseau, and how it ends up becoming the modern conception of ecosystems. [ABSTRACT FROM AUTHOR]

The paper deals with the need to make the Declaration more precise, as well as the search for mechanisms that would allow the practical application of the ethical wealth contained therein. [ABSTRACT FROM AUTHOR]

This study presents a statistical analysis conducted to determine a model which detects students at risk of academic failure at the Costa Rica Institute of Technology. The population is composed of students who were admitted to undergraduate programs in 1995. The dependent variable was the students' performance for seven years: drop-outs in the first semester, drop-outs in the second semester, drop-outs in any other semester, students currently registered and graduate students. The independent variables were: the Institute's entrance examination score and its components (High School, Math and Oral Components of the Academic Aptitude Test), type of high school (private or public, academic, technical or agricultural) geographic area, academic achievement indicators during the first semester, gender and major. A Logistic Regression Analysis model was used for an accurate classification of the 79.9% of the students in the categories of undergraduate and graduate. The model includes indicators of both academic performance and the number credits obtained in the students' majors. [ABSTRACT FROM AUTHOR]

The paper discusses the historical context of the Helsinki Declaration's (HD) formulation. Reference is made to the criminal research for which the Nazis stood trial at Nuremberg, as well as other postwar research abuses. Other documents are considered apart from the HD, for instance the Nuremberg Code, the Geneva Declaration and the International Code of Medical Ethics. This serves as an introduction to an analysis and assessment of the HD's evolution, developed in the following articles. [ABSTRACT FROM AUTHOR]

Livestock is an economic activity, dedicated to the breeding of animal species to take advantage of them and of its derivative products, as well as of livestock exploitation itself. However, when relating it to the sustainable use of natural resources in Northwest Mexico, there can be seen some situations that need to be addressed. The present study aims to analyze the production and conservation status of natural resources of beef cattle activity in the cow-calf system in Sonora, Mexico. The diagnosis was based on aspects of regionalization of livestock, the specific characteristics and issues of the systems, and the productive status of rangelands. The results showed that, despite the existence of signs of wildlife utilization and the importance of protecting the habitat status for livestock development in the state of Sonora, Mexico, it is important to implement a series of actions in order to increase the sustainable productivity of soil, soil water resources, the recovery of vegetation cover, improvement of livestock management practices, needs of research and technology transfer, as well as institutional linkage and training of professional human resources. [ABSTRACT FROM AUTHOR]

Opsanus beta is a permanent species in the Alvarado Lagoon System (ALS), Veracruz and eventhough it is not of economic importance, it might be actively involved in the energy transfer of the system. Currently, there is no information about the reproductive and ecological characteristics of this common fish, so this work aimed to evaluate those aspects, and to contribute with some ecological features. For this, a total of six sampling sites were selected and studied from April 2008 to December 2012. Per site, we determined fish seasonality, feeding, sex ratio, gonadosomatic index, hepatosomatic and condition factors for both sexes, as well as the fecundity and length-weight relationships. We also considered some environmental parameters such as temperature, water temperature, depth, salinity and pH. Our results on the environmental parameters analysis did not show significant differences for the study period; besides, salinity data confirmed an oligohaline environment and the rest of the physico-chemical parameters, varied in accordance with the climatic pattern in the area. We captured a total of 519 fishes, 311 (59.9 %) males and 208 (41.1 %) females; the proportion of males resulted favorable against females throughout the study. The standard length found along the study period showed that the average was higher in males than in females. The trophic spectrum was composed of 13 food items, principally crustaceans, molluscs and fishes; in addition, cannibalism was observed over young individuals during March and April. The most advanced stages of gonadal maturation were recorded from November to March for males, and from November to February in females; generally, the Gonadosomatic index (IGS) recorded the highest values from November to April. The Hepatosomatic Index (IHS) and the Condition Factor (FC) presented an inverse relationship with the Gonadosomatic index (IGS). The fecundity of this species ranged from 96 to 428 oocytes per female. The weight-length relationship by sexes and seasons, showed a higher growth rate for males than for females, and an allometric growth type. The biological and ecological information of O. beta in ALS evidenced the importance of this species and its ecological role in the structure and dynamics of these aquatic communities. This species may be used as a model for future proposals dealing with the management and sustainable use of this ecosystem. [ABSTRACT FROM AUTHOR]

Biodegradation of phenol in treated water from the oil industry to re-use in agricultural crops. Oil exploitation and the usage of its derivatives have undeniably contributed to the technological advance worldwide. This industrial activity, however, generates several by-products that can threaten environmental sustainability. Seawage, for example, can contain organic pollutants and heavy metals; therefore, its deposition must be preceded by adequate water treatment. In this study, we isolated, characterized, and molecularly identified eight bacteria on the basis of their capability to degrade phenol. First, we determined the rates of bacterial growth and phenol degradation using different concentrations of the aromatic hydrocarbon (500, 800 and 1 200 mg / L), and then used sequential statistical designs to select optimal conditions for its degradation. Results showed that all isolated strains were capable of degrading phenol as the sole carbon source; the degradation kinetics and phenol tolerance, however, widely varied among strains. We chose the strain Pseudomonas sp. Sps1 for further studies due to its remarkable tolerance and capability to degrade phenol. By using a Plackett Burman design, followed by a fractionated factorial design in which several carbon, nitrogen, and phosphorus sources were evaluated, and phenol degradation was used as the response variable, we found optimal conditions for phenol degradation by Sps1. Finally, we compared phenol degradation in seawage by the use or not of the optimal conditions established by the statistical methods. Results showed that biostimulation dramatically increased phenol degradation compared with the control. In conclusion, we found that bioaugmentation with the native bacteria Sps1 and a statistically-based biostimulation approach provided an economically and environmentally friendly alternative for the removal of pollutants from oil industry sewage. [ABSTRACT FROM AUTHOR]

C. acutus is cataloged in critical danger in Colombia. We studied its population at Bahia Portete, in order to survey the nesting activities and to obtain valuable information for a conservation management program. This study was undertaken with the participation of the Wayuü community using the Agreement Conservation Model, and took place during July 2007, August 2008, June and August 2009, and March to August 2010 and 2011. Sampling surveys were made by the use of transects along the coast, in order to find nests. For each nesting area found, we recorded the nests biometrics, eggs and hatchlings, fertility of the eggs and reproductive events. We explored a total of 55.12 km, and determined four nesting areas. Colonial nesting and the environmental variables were factors that affected the hatchling success. From the total of nests found, 37% were oriented towards North, and 48% were built next to Stenocereus griseus. Juyui island substrate was mostly constituted by sand (71.9%, 71.44%). The average number of eggs by nest was 28.42 ± 6.63, the largest egg diameter was 71.84 ± 3.54 mm, the average nest weight was 81.54 ± 9.99 g, and the hatchlings presented an average length of 25.47 ± 1.16 cm. For this specific site in Colombia, the reproductive period begins in March and ends in August. The few areas of nesting and the 95% fertility suggest the performance of a conservation management program for this species at Bahía Portete. Rev. Biol. Trop. 65 (1): 211-228. Epub 2017 March 01. [ABSTRACT FROM AUTHOR]