Étude du rapport entre la géométrie des fils et la rugosité des tissus

La suavidad de los tejidos es difícilmente cuantificable puesto que está asociada a una serie de sensaciones subjetivas. Se ha intentado evaluar objetivamente mediante diversos métodos. Uno de los parámetros cuantificables más importantes, que diversos autores relacionan con el tacto de los tejidos es su aspereza o rugosidad superficial. En este trabajo se estudia la relación entre la rugosidad superficial de una serie de tejidos y la deformación filar de los hilados que los constituyen; la deformación filar depende de la geometría de los hilados y esta, a su vez está condicionada por diversas variables. En el trabajo se establecen las relaciones entre la deformación filar y la composición, título y torsión de los hilados de PES/CV, en un intento de poder establecer como influyen estas variables en la rugosidad de los tejidos.The smoothness of the fabrics is hardly quantifies since is associated to a series of subjective sensations. It has been tried to evaluate objectively by means of diverse methods. One of the more important measurable parameters that diverse authors relate to the smoothless of a fabric is its superficial roughness. The present work studies the relationship between the superficial roughness of a series of fabrics and the deformation of the yarns that constitute them. The yarn deformation depends on the geometry of the yarn and this is, as well, depending of diverse variables. In the work the relationships between the yarn deformation and the account and torsion of yarns of different PES/CV compositions are also studied in an attempt of how these variables influence the superficial roughness of the fabrics.La douceur des tissus est difficilement quantifiable car elle est associée à une série de sensations subjectives. Elle a fait l'objet d'une tentative d'évaluation objective à l'aide de plusieurs méthodes. L'un des paramètres quantifiables les plus importants, que divers auteurs associent au tact des tissus, est leur âpreté ou rugosité superficielle. Cette étude porte sur le rappot entre la rugosité superficielle d'un série de tissus et la déformation filaire des filés qui les constituent; la déformation filaie dépend de la géométrie des filés et celle-ci est, à son tour, conditionnée par plusieurs variables. Des rapports son établis entre la déformation filaire et la composition, le titre et la torsion des filés de PES/CV, pour tenter d'établir comment ces variables jouent sur la rugosité des tissus

Conjunctival tumors in children: histopathologic diagnosis in 165 cases

ABSTRACT Purpose: Conjunctival tissue tumors have a varied presentation, and few series studies on pediatric patients have been published. The objective of this paper is to report the histopathologic diagnoses (spanning over 1988-2013) of conjunctival tumors in children younger than 14 years. Methods: We conducted a retrospective, descriptive, and observational study by reviewing the database of all children in whom a conjunctival tumor was surgically removed at Hospital de Ojos y Oídos "Dr. Rodolfo Robles V.," Benemérito Comité Pro Ciegos y Sordos de Guatemala. The data pertaining to gender, age, and histopathologic diagnosis of all cases was collected. The same ocular pathologist made all diagnoses. Results: One hundred sixty-five cases were found, with a mean age of 7.88 years, being 91 (55.15%) male subjects. Melanocytic lesions were the most common tumors found (30.91% of cases), with only one case (0.60%) being malignant. Conclusions: Melanocytic lesions were the most common tumors found, and of all the cases, only one was malignant; this was in a patient with xeroderma pigmentosum. These findings are consistent with those reported in other studies regarding the frequencies of the histopathology of conjunctival tumors in the pediatric population

Long-term Occupancy (1900–2015) of an Egyptian Vulture Nest

Peer reviewe

Spectrum Coexistence of LEO and GSO Networks: An Interference-Based Design Criteria for LEO Inter-Satellite Links

As small satellites become more capable through miniaturized electronics and on-board processing, constellations of low-cost satellites lunched in Low- Earth Orbit (LEO) become feasible. The increase in the number of LEO satellites drives the need for frequency coexistence between the LEO constellation systems with the already existing geostationary (GSO) satellite networks. In this context, it is crucial to design the communication links paying special attention to interference analysis. This is particularly true when the LEO satellite constellation exploit inter-satellite communication links (ISL). In this paper, a radio frequency interference analysis based on simulation of the dynamic satellite constellation is presented and the design parameters of the inter-satellite links are analyzed. The results suggest that carefully choosing the design parameters of the intersatellite links, spectrum coexistence of LEO and GSO networks may be possible.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Spectrum Coexistence of LEO and GSO Networks: An Interference-Based Design Criteria for LEO Inter-Satellite Links

As small satellites become more capable through miniaturized electronics and on-board processing, constellations of low-cost satellites lunched in Low- Earth Orbit (LEO) become feasible. The increase in the number of LEO satellites drives the need for frequency coexistence between the LEO constellation systems with the already existing geostationary (GSO) satellite networks. In this context, it is crucial to design the communication links paying special attention to interference analysis. This is particularly true when the LEO satellite constellation exploit inter-satellite communication links (ISL). In this paper, a radio frequency interference analysis based on simulation of the dynamic satellite constellation is presented and the design parameters of the inter-satellite links are analyzed. The results suggest that carefully choosing the design parameters of the intersatellite links, spectrum coexistence of LEO and GSO networks may be possible.Sociedad Argentina de Informática e Investigación Operativa (SADIO

A first approach to the Paleoentomology present in the Quaternarian sites of Atapuerca (Burgos, Spain): the subfossil oribatid fauna (Acari, Oribatida)

8 páginas, 3 figuras, 2 tablas.[ES] Los yacimientos cuaternarios de la Sierra de Atapuerca ofrecen interés mundial por haber hospedado varias especies de homínidos que vivieron en el último millón de años. En este contexto, durante la campaña de excavaciones de 2003 se realizó un muestreo puntual en algunos de sus yacimientos para obtener los primeros datos de restos de artrópodos que pudieran conservarse en los mismos. En este trabajo se presentan los resultados obtenidos de ácaros subfósiles pertenecientes al suborden de los oribátidos (Acari, Oribatida). Después de procesar los sedimentos, se obtuvieron un total de 7 individuos en el conjunto de los yacimientos muestreados, de los cuales 6 aparecieron en Gran Dolina en un nivel con datación en torno a los 300.000 años. Los ejemplares, identificados en su mayoría a nivel taxonómico de especie, pertenecen a las familias Cosmochthoniidae, Scheloribatidae, Oribatulidae y Hemileiidae. Dado el conocimiento que se dispone de la biología de los taxones encontrados, que pertenecen a géneros y especies presentes en la actualidad, se han realizado inferencias sobre los ambientes pretéritos en que los animales vivieron.[EN] The Atapuerca Quaternarian sites are of worldwide interest due to the presence of human remains belonging to the last million years. The oribatid mites (Acari, Oribatida) found in several archaeological samples extracted from the Atapuerca Quaternarian deposits, have been analyzed during the 2003 excavation campaign to study the Palaeoentomology of the site. The oribatid mite fauna consists of 7 individuals, 6 of which were obtained from Gran Dolina site (about 300.000 years old) and belong to families Cosmochthoniidae, Scheloribatidae, Oribatulidae and Hemileiidae. Most of the taxa were identified to species level. The results obtained were used as a basis to reconstruct the paleo-environments of the site in correspondence with the biological and ecological preferences of the taxa.Las investigaciones entomológicas de Atapuerca se realizaron dentro del Proyecto BOS2003-08938-C03-02.Peer reviewe

Paper-based chromatic toxicity bioassay by analysis of bacterial ferricyanide reduction

Water quality assessment requires a continuous and strict analysis of samples to guarantee compliance with established standards. Nowadays, the increasing number of pollutants and their synergistic effects lead to the development general toxicity bioassays capable to analyse water pollution as a whole. Current general toxicity methods, e.g. Microtox®, rely on long operation protocols, the use of complex and expensive instrumentation and sample pre-treatment, which should be transported to the laboratory for analysis. These requirements delay sample analysis and hence, the response to avoid an environmental catastrophe. In an attempt to solve it, a fast (15 min) and low-cost toxicity bioassay based on the chromatic changes associated to bacterial ferricyanide reduction is here presented. E. coli cells (used as model bacteria) were stably trapped on low-cost paper matrices (cellulose-based paper discs, PDs) and remained viable for long times (1 month at -20 °C). Apart from bacterial carrier, paper matrices also acted as a fluidic element, allowing fluid management without the need of external pumps. Bioassay evaluation was performed using copper as model toxic agent. Chromatic changes associated to bacterial ferricyanide reduction were determined by three different transduction methods, i.e. (i) optical reflectometry (as reference method), (ii) image analysis and (iii) visual inspection. In all cases, bioassay results (in terms of half maximal effective concentrations, EC50) were in agreement with already reported data, confirming the good performance of the bioassay. The validation of the bioassay was performed by analysis of real samples from natural sources, which were analysed and compared with a reference method (i.e. Microtox). Obtained results showed agreement for about 70% of toxic samples and 80% of non-toxic samples, which may validate the use of this simple and quick protocol in the determination of general toxicity. The minimum instrumentation requirements and the simplicity of the bioassay open the possibility of in-situ water toxicity assessment with a fast and low-cost protocolPostprint (author's final draft

Novel aromatic ring-hydroxylating dioxygenase genes from coastal marine sediments of Patagonia

<p>Abstract</p> <p>Background</p> <p>Polycyclic aromatic hydrocarbons (PAHs), widespread pollutants in the marine environment, can produce adverse effects in marine organisms and can be transferred to humans through seafood. Our knowledge of PAH-degrading bacterial populations in the marine environment is still very limited, and mainly originates from studies of cultured bacteria. In this work, genes coding catabolic enzymes from PAH-biodegradation pathways were characterized in coastal sediments of Patagonia with different levels of PAH contamination.</p> <p>Results</p> <p>Genes encoding for the catalytic alpha subunit of aromatic ring-hydroxylating dioxygenases (ARHDs) were amplified from intertidal sediment samples using two different primer sets. Products were cloned and screened by restriction fragment length polymorphism analysis. Clones representing each restriction pattern were selected in each library for sequencing. A total of 500 clones were screened in 9 gene libraries, and 193 clones were sequenced. Libraries contained one to five different ARHD gene types, and this number was correlated with the number of PAHs found in the samples above the quantification limit (<it>r </it>= 0.834, <it>p </it>< 0.05). Overall, eight different ARHD gene types were detected in the sediments. In five of them, their deduced amino acid sequences formed deeply rooted branches with previously described ARHD peptide sequences, exhibiting less than 70% identity to them. They contain consensus sequences of the Rieske type [2Fe-2S] cluster binding site, suggesting that these gene fragments encode for ARHDs. On the other hand, three gene types were closely related to previously described ARHDs: archetypical <it>nahAc</it>-like genes, <it>phnAc</it>-like genes as identified in <it>Alcaligenes faecalis </it>AFK2, and <it>phnA1</it>-like genes from marine PAH-degraders from the genus <it>Cycloclasticus</it>.</p> <p>Conclusion</p> <p>These results show the presence of hitherto unidentified ARHD genes in this sub-Antarctic marine environment exposed to anthropogenic contamination. This information can be used to study the geographical distribution and ecological significance of bacterial populations carrying these genes, and to design molecular assays to monitor the progress and effectiveness of remediation technologies.</p

Diseño y construcción de un banco de supercapacitores

En el presente informe se detallan el diseño y la construcción de un banco de supercapacitores (SC) junto con las simulaciones realizadas durante el proceso de diseño y las mediciones realizadas una vez construido. El mismo fue confeccionado con 20 elementos de 400 [F] nominales, combinados de forma de lograr una tensión nominal de 27 [V] y una capacidad nominal de 80 [F]. Se desarrollan todos los fundamentos teóricos básicos sobre supercapacitores y sistemas de balanceo para comprender su funcionamiento. El banco construido incorpora un novedoso método de balanceo de tensiones de celda basado en transistores mosfet, elemental para el funcionamiento del mismo al resguardar tanto la salud del usuario como de los SC. Además posee un sensor de corriente, sensores de temperatura y un amplificador de tensión aislado.The present work specifies the designing and construction processes of a supercapacitor bank. In order to comprehend the operation of the entire system, all the theoretical and fundamental knowledge about it is introduced. To begin with, there is a brief introduction of ultracapacitors (SC) and, taken that information into account, the supercapacitor bank is implemented with ultracapacitors. The elements are arranged to obtain a nominal working voltage of about 26.5 [V], with 82.5 [F] properly measured. A balancing method for each cell of the supercapacitor stack is needed, as well as an analog temperature sensor, a current Hall Effect sensor, and an optocoupled isolated voltage sensor. The bank is designed to be implemented in a complex functional hybrid energy generation system. Finally, a set of measures on the system are presented to verify the design, to characterize both the supercapacitor stack and the chosen balancing system method.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Spectrum Coexistence of LEO and GSO Networks: An Interference-Based Design Criteria for LEO Inter-Satellite Links

As small satellites become more capable through miniaturized electronics and on-board processing, constellations of low-cost satellites lunched in Low- Earth Orbit (LEO) become feasible. The increase in the number of LEO satellites drives the need for frequency coexistence between the LEO constellation systems with the already existing geostationary (GSO) satellite networks. In this context, it is crucial to design the communication links paying special attention to interference analysis. This is particularly true when the LEO satellite constellation exploit inter-satellite communication links (ISL). In this paper, a radio frequency interference analysis based on simulation of the dynamic satellite constellation is presented and the design parameters of the inter-satellite links are analyzed. The results suggest that carefully choosing the design parameters of the intersatellite links, spectrum coexistence of LEO and GSO networks may be possible.Sociedad Argentina de Informática e Investigación Operativa (SADIO