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El presente artículo ofrece una perspectiva comparada de las percepciones y experiencias de profesorado universitario de Chile, México, Ecuador y Colombia en la educación remota de emergencia por COVID-19, durante el año 2020, permitiendo visualizar desafíos y orientaciones para la gestión de la educación superior. Se realizó un estudio mixto concurrente en el que participaron 1008 docentes de enseñanza superior que realizaron clases en ese año. Se destacan de forma transversal los sentimientos de ansiedad, apatía y estrés experimentados por el profesorado. Los participantes de Chile mostraron una percepción más baja en la calidad de la relación docente-estudiante, en la autoeficacia docente y la experiencia de emociones agradables. Se reportan como ventajas los aprendizajes asociados al uso de tecnologías, la percepción de seguridad en el hogar y una mejor gestión del tiempo. Desde la integración de datos se devela un foco pedagógico en Colombia y Chile versus un foco centrado en la relación profesorado-alumnado en México y Ecuador respecto de los procesos de enseñanza aprendizaje. Se plantean reflexiones respecto de la integración de la dimensión emocional en los procesos de enseñanza-aprendizaje remotos, y la necesidad de avanzar en la reducción de brechas tecnológicas y digitales en docentes y estudiantes.

A water flow and velocity aluminum-coated Fiber Bragg Grating sensor system for open channels was designed, simulated and tested. The sensing head was designed, ruggedized and customized to measure velocities at different depths, in order to calculate the discharge in open channels. This paper shows, for the first time to our knowledge, the simulation of such kind of fiber sensors in open channels. This work was supported in part by projects PID2019-107270RB-C02, funded by MCIN/AEI/10.13039/501100011033 and FEDER “A way to make Europe”, and TED2021-130378B-C22 funded by MCIN/AEI/10.13039/501100011033 and European Union “Next generation EU”/PTR.

A Mg-based composite material has been produced by the consolidation at room temperature of a Mg-5wt.% Ni-2wt.% Nb2O5 powder mixture subjected to high-pressure torsion (HPT), one of the processing methods to induce severe plastic deformations. The microstructure, density, and microhardness of the consolidated disks were characterized after the application of up to 30 revolutions in torsion under compression stresses of 3 and 5 GPa. According to the density measurements, the composite was consolidated in full after the application of five revolutions, although disks subjected to only one revolution exhibited densities close to the maximum measured value. On the other hand, grain size and microhardness measurements showed that differences existed at locations near the center and the periphery of the HPT-processed disks. Under the stress of 5 GPa, the grain size in the central regions stabilized at about 0.35 μm after five revolutions, while at the peripherical regions it gradually decreased with an increasing number of revolutions down to about 0.15 μm after 30 revolutions. In turn, the microhardness measured along a diametral cross section steadily increased with the number of revolutions between 1 and 10 revolutions, maintaining a gradient from the center to the periphery in all cases. With the application of 20 and 30 revolutions, only the peripheral regions increased considerably in hardness. It was discovered that the magnesium particles in the initial powder mixture had formed an oxide—hydroxide surface layer, which changed the expected final density of the consolidated material by about 2 to 4.5%. This superficial contamination of the Mg powders did not prevent the material from achieving full consolidation.

Despite the dominance of the Caribbean as the leading cruise destination in the world, research that focuses on the network of cruise ports in the region is limited. To fill this research gap, the current study carried out social network analysis (SNA) to inquire into cruise port interconnections and their influence on the operation of the entire Caribbean port network. The results are summarized as follows: First, in terms of connections among ports linked to the Caribbean region, a European port and a Southampton harbor exhibit the most significant in-degree and out-degree centrality. Nevertheless, ports within the Caribbean region are still significantly represented as regards both indexes. Second, in the matter of port influence, Caribbean ports are considerably the most important with respect to hub and authority centrality (HAC), especially those located in Florida and the eastern Caribbean. This research contributes to industry through its presentation of an extended panorama of the cruise network in the region, subjecting several ports to respective analyses that describe their principal characteristics and attractiveness in the industry.

Wetlands are crucial hydrological features that provide benefits, including ecosystem services and habitat conservation, protection from flooding associated with sea level rise and extreme events, water storage and treatment, recreation, and aesthetics, among others. Peru is one of the few countries in Latin America that has not developed a national wetland inventory. While this can in part be attributed to the limited availability of peer-reviewed publications in the English literature, a larger quantity of Peruvian wetland-related publications are available in Spanish, and are less accessible to the global population. In this paper, we developed an extensive review and synthesis of the Spanish literature, including university theses, peer-reviewed articles, and government reports. Our report focuses on evaluating the state of the art of Peruvian wetlands in terms of temporal evolution, geographical distribution, vested institutions, research topics (e.g., water quality, fauna, flora, microorganisms, etc.), and advances toward the conservation of wetlands. The analysis identified 274 wetland-related publications in Spanish (188 theses, 83 peer-reviewed, and 6 government reports) and a temporal increase in dissemination over the past two decades. The reports encompassed 161 distinct wetlands distributed nationwide; however, most of the investigations focused on only a few wetland bodies with a disproportionate concentration in just three administrative regions. This reveals that wetland-related research is unevenly distributed in Peru, and highlights a need to extend this knowledge to underrepresented systems and regions. Although Peru ranks third in South America for protected (Ramsar) wetland areas, case studies have revealed that wetlands in the country are vulnerable to human activities. Recent national legislation established in 2021 should help to address this challenge, as before this time, there was a more decentralized approach, whereby each administrative region held responsibility for the protection of their own wetlands. Collective findings indicate that research activity should be increased nationally in order to better understand the function and benefits of wetlands throughout Peru, in addition to the continued development and enforcement of regulations designed to protect these valuable ecosystems. Finally, since a national Peruvian wetland inventory is urgently needed, this analysis provides a baseline for this development of, as well as identifying gaps in, knowledge needed for appropriate national representation.

Infections with globally disseminated Shiga toxin-producing

Factor VII Activating protease (FSAP) has a protective effect in diverse disease conditions as inferred from studies in FSAP-/- mice and humans deficient in FSAP activity due to single-nucleotide polymorphism. The zymogen form of FSAP in plasma is activated by extracellular histones that are released during tissue injury or inflammation or by positively charged surfaces. However, it is not clear whether this activation mechanism is specific and amenable to manipulation. Using a phage display approach, we have identified a Cys-constrained 11 amino acid peptide, NNKC9/41, that activates pro-FSAP in plasma. The synthetic linear peptide has a propensity to cyclize through the terminal Cys groups, of which the antiparallel cyclic dimer, but not the monocyclic peptide, is the active component. Other commonly found zymogens in the plasma, related to the hemostasis system, were not activated. Binding studies with FSAP domain deletion mutants indicate that the N-terminus of FSAP is the key interaction site of this peptide. In a monoclonal antibody screen, we identified MA-FSAP-38C7 that prevented the activation of pro-FSAP by the peptide. This antibody bound to the LESLDP sequence (amino acids 30-35) in an intrinsically disordered stretch in the N-terminus of FSAP. The plasma clotting time was shortened by NNKC9/41, and this was reversed by MA-FSAP-38C7, demonstrating the utility of this peptide. Peptide NNKC9/41 will be useful as a tool to delineate the molecular mechanism of activation of pro-FSAP, elucidate its biological role, and provide a starting point for the pharmacological manipulation of FSAP activity. ispartof: ACS CHEMICAL BIOLOGY vol:17 issue:9 pages:2631-2642 ispartof: location:United States status: published

Hp infection was found to alter metaplasia and accelerate dysplasia in mice. Thus, Hp can promote gastric preneoplastic progression, in addition to its known role in initiating chronic inflammation., More than 80% of gastric cancer is attributable to stomach infection with Helicobacter pylori (Hp). Gastric preneoplastic progression involves sequential tissue changes, including loss of parietal cells, metaplasia and dysplasia. In transgenic mice, active KRAS expression recapitulates these tissue changes in the absence of Hp infection. This model provides an experimental system to investigate additional roles of Hp in preneoplastic progression, beyond its known role in initiating inflammation. Tissue histology, gene expression, the immune cell repertoire, and metaplasia and dysplasia marker expression were assessed in KRAS+ mice +/−Hp infection. Hp+/KRAS+ mice had severe T-cell infiltration and altered macrophage polarization; a different trajectory of metaplasia; more dysplastic glands; and greater proliferation of metaplastic and dysplastic glands. Eradication of Hp with antibiotics, even after onset of metaplasia, prevented or reversed these tissue phenotypes. These results suggest that gastric preneoplastic progression differs between Hp+ and Hp− cases, and that sustained Hp infection can promote the later stages of gastric preneoplastic progression.

More than 80% of gastric cancer is attributable to stomach infection with Helicobacter pylori (Hp), even though the bacterium is not always present at time of diagnosis. Infection is thought to lead to cancer by promoting the accumulation of oncogenic mutations downstream of inflammation; once oncogenic pathways become activated, infection may become dispensable for cancer development. Gastric preneoplastic progression involves sequential changes to the tissue, including loss of parietal cells, spasmolytic polypeptide-expressing metaplasia (SPEM), intestinal metaplasia (IM) and dysplasia. In mice, active KRAS expression recapitulates these tissue changes in the absence of Hp infection. This model provides an experimental system to investigate whether Hp infection has additional roles in preneoplastic progression, beyond initiating inflammation. Mice were assessed by evaluating tissue histology, gene expression changes, the immune cell repertoire, and expression of metaplasia and dysplasia markers. Compared to Hp-/KRAS+ mice, Hp+/KRAS+ mice had i) severe T cell infiltration and altered macrophage polarization; ii) altered expression of metaplasia markers, including increased expression of CD44v9 (SPEM) and decreased expression of TFF3 (IM); iii) more dysplastic (TROP2+) glands; and iv) greater proliferation of metaplastic and dysplastic glands. Hp was able to persistently colonize the stomach during the onset of these tissue changes, and eradication of Hp with antibiotics prevented metaplastic, dysplastic and proliferation marker changes. Collectively, these results suggest that gastric preneoplastic progression differs between Hp+ and Hp-cases, and that sustained Hp infection can promote the later stages of gastric preneoplastic progression, in addition to its established role in initiating chronic inflammation.

The toxigenic conversion of Escherichia coli strains by Shiga toxin-converting (Stx) bacteriophages were prominent and recurring events in the stepwise evolution of enterohemorrhagic E. coli (EHEC) O157:H7 from an enteropathogenic (EPEC) O55:H7 ancestor. Atypical, attenuated isolates have been described for both non-sorbitol fermenting (NSF) O157:H7 and SF O157:NM serotypes, which are distinguished by the absence of Stx, the characteristic virulence hallmark of Stx-producing E. coli (STEC). Such atypical isolates either never acquired Stx-phages or may have secondarily lost stx during the course of infection, isolation, or routine subculture; the latter are commonly referred to as LST (Lost Shiga Toxin)-isolates. In this study we analyzed the genomes of 15 NSF O157:H7 and SF O157:NM strains from North America, Europe, and Asia that are characterized by the absence of stx, the virulence hallmark of STEC. The individual genomic basis of the Stx (-) phenotype has remained largely undetermined as the majority of STEC genomes in public genome repositories were generated using short read technology and are in draft stage, posing a major obstacle for the high-resolution whole genome sequence typing (WGST). The application of LRT (long-read technology) sequencing provided us with closed genomes, which proved critical to put the atypical non-shigatoxigenic NSF O157:H7 and SF O157:NM strains into the phylogenomic context of the stepwise evolutionary model. Availability of closed chromosomes for representative Stx (-) NSF O157:H7 and SF O157:NM strains allowed to describe the genomic basis and individual evolutionary trajectories underlying the absence of Stx at high accuracy and resolution. The ability of LRT to recover and accurately assemble plasmids revealed a strong correlation between the strains' featured plasmid genotype and chromosomally inferred clade, which suggests the coevolution of the chromosome and accessory plasmids. The identified ancestral traits in the pSFO157 plasmid of NSF O157:H7 strain LSU-61 provided additional evidence for its intermediate status. Taken together, these observations highlight the utility of LRTs for advancing our understanding of EHEC O157:H7/NM pathogenome evolution. Insights into the genomic and phenotypic plasticity of STEC on a lineage- and genome-wide scale are foundational to improve and inform risk assessment, biosurveillance, and prevention strategies.

El desarrollo de aplicaciones web ha alcanzado gran popularidad a lo largo del mundo. Disímiles son las aplicaciones que se realizan que responden a la solución de diversos problemas sociales. En la búsqueda de visiones y soluciones globales, en los últimos años se ha popularizado el concepto de Experiencia de Usuario o Diseño de Experiencias de Usuario. Una de las disciplinas que integran este concepto es el Diseño Emocional el cual aborda que el producto puede evocar emociones de forma explícita, expresando afecto; o implícita, a través de su estética. Todo producto intenta emular estados afectivos con la intención de modelar así los estados afectivos o emocionales del usuario. En el presente trabajo se evidencia un estudio preliminar desarrollado en la investigación en curso con el propósito de demostrar la necesidad de incluir en el proceso de desarrollo de aplicaciones web del centro de Geoinformática y Señales Digitales una estrategia basada en el diseño emocional.

Zohar Amar and Efraim Levy cover a rarely-touched topic on early medieval Arabic medicine. Although the title Arabian Drugs in Early Medieval Mediterranean Medicine suggests that the book primarily focuses on Arab medicine, by seeking the roots of Arab medicine the authors delve into the medical history of Arab neighbors from Greeks and Persians to Indians. By carefully examining the usage of various plants, herbs, and other remedies that originated from the Greek, Indian, and Persian societies, the authors seek to find how these societies contributed to the development of early medieval Arabic medicine. The book further traces the origins of pharmacology prior to the development of Arab medicine. Relying on an ancient Greek source, materia medica, a book of collected pharmacological knowledge, the authors find heavy Greek influence on the development of Arab medicine. Materia medica guided physicians to help their patients from the first century AD to the twentieth century and has been expanded over the centuries.

The volume fraction of red blood cells (RBCs) in a capillary affects the degree to which platelets are promoted to marginate to near a vessel wall and form blood clots. In this work we investigate the relationship between RBC hematocrit and platelet adhesion activity. We perform experiments flowing blood samples through a microfluidic channel coated with type 1 collagen and observe the rate at which platelets adhere to the wall. We compare these results with three-dimensional boundary integral simulations of a suspension of RBCs and platelets in a periodic channel where platelets can adhere to the wall. In both cases, we find that the rate of platelet adhesion varies greatly with the RBC hematocrit. We observe that the relative decrease in platelet activity as hematocrit falls shows a similar profile for simulation and experiment.

Refrigeration of platelets (4°C) provides the possibility of improving transfusion practice over the current standard-of-care, room temperature (RT) storage. However, the increased level of platelet activation observed at 4°C in vitro is cause for concern of uncontrolled thrombosis in vivo. In this study, we assessed the safety of 4°C-stored platelets by evaluating their response to physiologic inhibitors prostacyclin (PGI2) and nitric oxide (NO). Apheresis platelets were collected from healthy donors (n = 4) and tested on Day 1 (fresh) or Day 5 (RT- and 4°C-stored) after treatment with PGI2 and NO or not for: thrombin generation; factor V (FV) activity; intracellular free calcium, cAMP and cGMP; ATP release; TRAP-induced activation; aggregation to ADP, collagen, and TRAP, and adhesion to collagen under arterial flow. Data were analyzed using two-way ANOVA and post-hoc Tukey test for multiple comparisons, with significance set at P

More than 80% of gastric cancer is attributable to stomach infection with Helicobacter pylori (Hp). Gastric preneoplastic progression involves sequential tissue changes, including loss of parietal cells, metaplasia and dysplasia. In transgenic mice, active KRAS expression recapitulates these tissue changes in the absence of Hp infection. This model provides an experimental system to investigate additional roles of Hp in preneoplastic progression, beyond its known role in initiating inflammation. Tissue histology, gene expression, the immune cell repertoire, and metaplasia and dysplasia marker expression were assessed in KRAS+ mice +/−Hp infection. Hp+/KRAS+ mice had severe T-cell infiltration and altered macrophage polarization; a different trajectory of metaplasia; more dysplastic glands; and greater proliferation of metaplastic and dysplastic glands. Eradication of Hp with antibiotics, even after onset of metaplasia, prevented or reversed these tissue phenotypes. These results suggest that gastric preneoplastic progression differs between Hp+ and Hp− cases, and that sustained Hp infection can promote the later stages of gastric preneoplastic progression.

Desde su surgimiento, el objetivo fundamental del estándar OBD [On Board Diagnostics] ha sido el control de los gases emitidos por los automóviles y de sus efectos en el medio ambiente. Este proyecto implementa un sistema basado en el protocolo OBD-II sobre un bus CAN [Controller Area Network], que permite visualizar variables en tiempo real y realizar un diagnóstico del estado del automóvil que muestra los códigos de funcionamiento, falla y rendimiento energético. Los sistemas de diagnóstico abordo permiten conocer los códigos de fallo almacenados y un gran número de variables de especial relevancia, como la velocidad, el nivel de combustible y el nivel de emisión de dióxido de carbono, en tiempo real. Se implementó un sistema OBD-II centrado en el extremo del bus, que corresponde al escáner o unidad de diagnóstico, en una placa Arduino Mega 2560 conectada a un módulo compuesto transceiver-controller CAN. El scanner posee una conexión USB que facilita visualizar los datos recuperados de forma versátil en una PC a través de una interfaz gráfica creada en LabVIEW™. From its origin, the main objective of the OBD [On Board Diagnostics] standard has been the control of the gases emitted by the vehicles and its corresponding effects in the environment. This project implements a system based on the OBD-II protocol over a CAN [Controller Area Network] bus, which allows the visualization of variables in real-time and the performing of a diagnosis of the vehicle state showing the operating, failure, and energy consumption codes. The on board diagnosis systems allow to retrieve the stored failure codes together with a large number of variables –important for the diagnosis– such as speed, fuel level, and CO2 [Carbon Dioxide] emissions in real-time. We implemented an OBD- II system located at the end of the test vehicle (a bus) –which corresponds to the scanner or diagnosis unit– in an Arduino Mega 2560 development board connected to a CAN transceiver-controlled composed module. The scanner has a USB connection that eases the graphical visualization of data in a PC through an interface created in LabVIEW.

En esta investigación se presenta el desarrollo y validación de dos propuestas de solución mediante técnicas de procesamiento de información visual para la estimación y corrección del error en el desplazamiento del robot humanoide NAO debido a factores inherentes a su sistema de locomoción. La primera propuesta se basa en la detección de líneas mediante la transformada de Hough y la segunda se basa en el registro de imágenes utilizando como información la textura del suelo. El espacio de pruebas donde se desarrollan las técnicas es un laberinto fabricado en madera con una superficie de 180 cm x 300cm y paredes de 60 cm de altura. Se evalúa cada técnica al determinar el error de posición tanto en desplazamientos como en rotaciones después de recorrer una distancia determinada para alcanzar una posición final deseada, evaluando los tiempos de procesamiento para finalmente determinar cuál de las dos técnicas es más adecuada para realizar la corrección de posicionamiento dentro del entorno estructurado seleccionado. En el penúltimo capítulo de esta tesis se describen algunas aplicaciones que se han podido lograr gracias al desarrollo de este trabajo de investigación, donde se destaca la participación en la competencia internacional RoboCup 2017 en Nagoya Japón.

In July 2010, the United Nations General Assembly explicitly recognized the human right to water and sanitation, reaffirming that clean drinking water is essential for the realization of all the human rights. Therefore, controlling water quality should be a priority. In this context, it is interesting to make a simple, sustainable and low-cost system, in order take control over water quality parameters. This project main goal is to design and implement a water quality monitoring system on distribution networks to population or another interesting environment. It incorporates a quick alert system of flooding on low-altitude zones. It has mobile communication interface, over GSM, GPRS or 3G network, to send alarm and monitoring signals En julio de 2010, la Asamblea General de las Naciones Unidas reconoció el derecho humano al agua y al saneamiento, reafirmando que el acceso a agua potable limpia es esencial para la realización de todos los derechos humanos. Por lo tanto, controlar la calidad del agua debe ser una prioridad. En este marco, es interesante realizar un sistema sencillo, sostenible y de bajo costo, que facilite el control de los parámetros de calidad del agua. El objetivo general de este trabajo es diseñar e implementar un sistema de de monitoreo de la calidad del agua en redes de distribución a la población u otros escenarios donde sea necesaria analizar la potabilidad de la misma. Además, incorpora un sistema de alerta ante la posible inundación de los embalses en zonas bajas o de interés general. Dispone de una interfaz de comunicaciones móviles, soportado sobre la red GSM, GPRS y 3G, para el envío de señales de monitoreo y alarma.

Study objective Serious adverse outcomes associated with skin and soft tissue infections are uncommon, and current hospitalization rates appear excessive. It would be advantageous to be able to differentiate between patients who require high-level inpatient services and those who receive little benefit from hospitalization. We sought to identify characteristics associated with the need for high-level inpatient care among emergency department patients presenting with skin and soft tissue infections. Methods We conducted a nonconcurrent review of existing records to identify emergency department (ED) patients treated for skin and soft tissue infections. For each case, we recorded the presence or absence of select criteria and whether the patient needed high-level care, defined as ICU admission, operating room surgical intervention, or death as the primary outcome. We applied recursive partitioning to identify the principal criteria associated with high-level care. Results We identified 2,923 patients, including 84 experiencing high-level events. Recursive partitioning identified 6 variables associated with high-level outcomes: abnormal computed tomography, magnetic resonance imaging, or ultrasonographic imaging result; systemic inflammatory response syndrome; history of diabetes; previous infection at the same location; older than 65 years; and an infection involving the hand. One or more of these variables were present in all 84 patients requiring high-level care. Conclusion A limited number of simple clinical characteristics appear to be able to identify skin and soft tissue infection patients who require high-level inpatient services. Further research is needed to determine whether patients who do not exhibit these criteria can be safely discharged from the ED.

Este trabajo tuvo como objetivo analizar la relación entre los estilos de aprendizaje y el aprendizaje colaborativo en cursos virtuales en una Universidad de Educación Superior en cursos a distancia. El estudio se realizó bajo un enfoque metodológico de tipo cualitativo, en un curso virtual transversal de primer semestre de educación superior a través de bitácoras de observación, comportamientos en el aula virtual y cuestionarios aplicados a los estudiantes.Se presentan los hallazgos sobre los comportamientos del aprendizaje colaborativo en los estudiantes según sus estilos de aprendizaje, examinando múltiples formas de organización de equipos de trabajo, destacando aspectos como comunicación, interacción, argumentación crítica, desempeño grupal e individual, liderazgo y actitud propositiva, relacionando los estilos de aprendizaje y el aprendizaje colaborativo a partir de la conformación de los equipos de trabajo. La evidencia parece demostrar que los estudiantes agrupados en equipos con distintos estilos de aprendizaje obtienen una mayor integración y logro de objetivos.

Four genotypes of carioca bean were accelerate aged (40 0C/75% relative humidity) and evaluated to determine if differences in postharvest darkening trait was an enzymatic or non-enzymatic process. Chromaticity a* was the colour parameter with major alterations, and increase in chromaticity b* often masked the reddish of tegument. Peroxidase activity was not detected. Polyphenoloxidase remained active along the storage time, but its activity was higher in the lighter genotypes. Flavonoid, proanthocyanidin and total phenol content were much higher in darker genotypes, although just this last component presented significant alterations. Genotypes showed different susceptibilities to the darkening independent of phenolic content. Results of principal response curves analyse suggested different pathways for the darkening process: darkening in lighter genotypes seem to be mostly due to polyphenoloxidase activity while in dark ones there are the combination of enzymatic and non-enzymatic oxidation. Made available in DSpace on 2022-05-20T11:12:32Z (GMT). No. of bitstreams: 1 CNPAF-2016-pzb.pdf: 1410426 bytes, checksum: 89e4fdb4183930d9e459166ccfe77983 (MD5) Previous issue date: 2016

Jatropha elliptica (Pohl) Oken, popularly known as teiu potato, is widely used in folk medicine as a purgative and in the treatment of snake bites. There is no scientific data on the physicochemical characterization or anti-nutritional compounds, nor are there any reports on the application of this root in the production of flours for food purposes. Thus, the objective of this work was to contribute with new knowledge concerning the production yield of teiu potato root flour, characterize its physical, chemical and technological properties, and determine its anti-nutritional and toxicological factors. The flour was obtained on three repetitions (batches) and all analyses were carried out in triplicate for each repetition. The flour production yield was 34.29%, and the product obtained was an orange powder with a carbohydrate content of 77.55 g·100 g-1, high contents of total dietary fiber (22.8 g·100 g-1), protein (8.3 g·100 g-1) and ash (3.5 g·100 g-1), and a low lipid (0.8 g·100 g-1) content. The thermogram of the flour showed three endothermic peaks: temperature of gelatinization of the flour starch (77.42 °C); glass transition (106.55 °C) and protein and lipid-amylose complexes (131.77 °C). The flour presented antioxidant potential (89.59% of DPPH discoloration), a high concentration of phenolic compounds (12.67 mg eq gallic acid·100 g-1), nitrates (4.4 g·Kg-1), tannins (5.4 g tannic acid·100 g-1) and trypsin inhibitors (4.3 UTI·mg-1). The teiu potato flour requiring further, more profound studies before being indicated for human nutrition, due to the presence of anti-nutritional factors and the toxicity presented in the test with Artemia salina.

BACKGROUND: Whole blood (WB) has been used in combat since World War I as it is readily available and replaces every element of shed blood. Component therapy has become standard; however, recent military successes with WB resuscitation have revived the debate regarding wider WB use. Characterization of optimal WB storage is needed. We hypothesized that refrigeration preserves WB function and that a pathogen reduction technology (PRT) based on riboflavin and ultraviolet light has no deleterious effect over 21 days of storage. STUDY DESIGN AND METHODS: WB units were stored for 21 days either at 4 C or 22 C. Half of each temperature group underwent PRT, yielding four final treatment groups (n = 8 each): CON 4 (WB at 4 C); CON 22 (WB at 22 C); PRT 4 (PRT WB at 4 C); and PRT 22 (PRT WB at 22 C). Testing was at baseline, Days 1-7, 10, 14, and 21. Assays included coagulation factors; platelet activation, aggregation, and adhesion; and thromboelastography (TEG). RESULTS: Prothrombin time (PT) and partial thromboplastin time increased over time; refrigeration attenuated the effects on PT (p /= 0.009). Aggregation decreased over time (p /= 0.001); losses were attenuated by refrigeration (p /= 0.001). Refrigeration preserved TEG parameters (p /= 0.001) and PRT 4 samples remained within normal limits throughout the study. Refrigeration in combination with PRT inhibited fibrinolysis (p /= 0.001) and microparticle formation (p /= 0.031). Cold storage increased shear-induced platelet aggregation and ristocetin-induced platelet agglutination (p /= 0.032), as well as GPIb-expressing platelets (p /= 0.009). CONCLUSION: The in vitro hemostatic function of WB is largely unaffected by PRT treatment and better preserved by cold storage over 21 days. Refrigerated PRT WB may be suitable for trauma resuscitation. Clinical studies are warranted.

Seeds from endemic Brazilian fruits (Mangaba, Cagaita, Jatobá and Araticum), previously confirmed to be toxic using Artemia salina bioassay were exposed to different temperatures and heating times aiming to test inhibitory effects on toxicity, as a first approach to characterize and identify toxic compounds and their thermal stability. After treatment, water extracts from kernels were filtered and added to Artemia cultures for 24 hours after which the survival of cultures was calculated. The inhibitory effect of temperature on toxicity was significant, whereas toxins from Mangaba and Cagaita were the most labile, showing 90% Artemia survival after heating at 78 °C for 2 minutes and 10 minutes, respectively. The most resistant toxins were those found in Araticum seeds which remained active (0% Artemia survival), even after heating at 160 °C for 12 min. Response surfaces and statistical multivariate analysis showed a significant effect for both temperature and heating time (linear fit) on Cagaita and Mangaba toxicity reduction, while the temperature factor was more significant in Jatobá samples. The results confirm the need to adopt safety procedures during the manufacture of industrialized derivatives for these fruits, in order to minimize toxicity risks after their consumption.

The primary purpose of this study was to investigate the effect that turbulent pipe flow has on the electrochemical behaviour of a 3-amino-1,2,4-triazole (aminotriazole or 3-AT)-based corrosion inhibitor. The experiments were carried out in a 4-L laboratory pipe loop. A metallic ring made of API X52 pipeline steel was located in a linear segment of the pipe loop and acted as a test electrode. The test environment used in all experiments was a 3% NaCl solution saturated with CO2 at 20 °C. The range of Reynolds number studied was from 6518 to 32118, assuring turbulent flow conditions in the pipe loop. Electrochemical impedance spectroscopy (EIS) was used to determine the electrochemical behavior of the steel in the environment at different flow rates and inhibitor concentrations. It was found that the electrochemical impedance of the system is dependent on both exposure time and flow conditions (Reynolds number). It was also detected that EIS data can give information on the persistence of the inhibitor film formed upon the metal surface. Therefore, in order to qualify the performance of the corrosion inhibitor, it is necessary to define the flow conditions at which it is intended to work.

O objetivo do trabalho foi identificar métodos para superar a dormência e promover a germinação de sementes de Stryphnodendron adstringens e Stryphnodendron polyphyllum. Sementes de ambas as espécies foram submetidas aos seguintes tratamentos desuperação de dormência: testemunha, escarificação mecânica (lixa número 220), H2O quente (temperatura inicial de 87oC) por 5 e por 15 minutos, escarificação química com H2SO4 (95%) por 30, 45, 60, 75, 90 e 105 minutos, choque térmico 1 (0oC e 50% UR por 1h e após imersão em água por 10 min. Ti=85oC Tf=57oC), choque térmico 2 (40oC e 40%UR por 6 h e após imersão em água por 10 min. Ti=0oC Tf=3oC), choque térmico 3 (40oC e 40% UR por 6h e após imersão em água por 10 min Ti=25oC Tf=25oC). Conclui-se que sementes pertencentes ao mesmo gênero, mas de espécies diferentes, respondem de forma diversa a alguns tratamentos de superação de dormência. Para ambas as espécies, a escarificação das sementes com H2SO4 (45 minutos) ou lixa são métodos que podem ser utilizados com máxima eficiência para a superação da dormência e promoção da germinação.The aim of this research was to identify methods for breaking dormancy and promoting germination of Stryphnodendron adstringens and S. polyphyllum seeds. Seeds of both species were submitted to the following treatments for breaking dormancy: control; mechanical scarification (sandpaper number 220); hot water (initial temperature of 87°C) for 5 and 15 minutes; chemical scarification with H2SO4 (95%) for 30, 45, 60, 75, 90 and 105 minutes; thermalshock 1 (0°C and 50% RH for 1 h and thereafter 10 minutes into water Ti=85°C, Tf=57°C); thermic shock 2 (40°C and 40% RH for 6 h and thereafter 10 minutes into water, Ti=0°C, Tf=3°C); thermal shock 3 (40°C and 40% RH for 6h and thereafter 10 minutes into water, Ti=25°C, Tf=25°C). We concluded that seeds belonging to samegenus but from different species answered differently to some treatments for breaking dormancy. Chemical scarification with H2SO4 (45 minutes) and mechanical scarification with sandpaper are methods that can be employed with efficiency to break dormancy and promote germination for both species.

Artemia salina bioassay was used to assess toxicity of seeds and kernels of Brazilian fruits from cerrado (central high plains region) and other inner regions of the country. Water extracts of the kernels were filtered and added to Artemia cultures containing ten individuals per mL. Dose - response curves were constructed, and LD50 values were calculated. Pure potassium cyanide standard was used to draw a calibration curve for comparison to detect the presence of cyanide in the samples tested. Extracts of the seeds of araticum, mangaba, cagaita, jatoba, and tucuma were found toxic to Artemia salina, and some of the dose - response curves were very similar in shape to those obtained with pure potassium cyanide standards, while the samples of baru, caja-manga, siriguela, trauma, and veludo showed no toxicity at all. The Guignard test, specific for cyanide detection, showed negative results in all toxic samples, suggesting the presence of other toxic compounds rather than cyanide. The comparison of araticum dose - response curve with those of other annonaceous fruits suggests the presence acetogenins as the main toxic compounds in the seeds. These results could be useful to prevent poisoning by industrial derivatives of the fruits studied.

Introduction. A critical challenge faced by sustainability science is to develop robust strategies to cope with highly uncertain social and ecological dynamics. The increasing intensity with which human societies utilize (limited) natural resources is fueling the global debate and urging the development of resource management methodologies/policies to effectively deal with very demanding socio-bio-economical issues. Unfortunately, despite concerted efforts by governments, many natural resources continue to be poorly managed. The collapse of many fisheries worldwide is the most notable example (Clark, 2006; Clark et al., 2006; Holland, Gudmundsson; Myers, Worm 2003; Sethi et al., 2005) but other examples include forests (Moran, Ostrom), groundwater basins (Shah, 2000), and soils (ISRIC, 1990). The suggested causes are varied but (Clark, 2006) highlights two: (1) lack of consideration of economic incentives actually faced by economic agents and (2) uncertainty associated with the dynamics of biological populations. In the case of fisheries, Clark notes that “complexity and uncertainty will always limit the extent to which the effects of fishing can be understood or predicted” (Clark, 2006, p. 98). This suggests that we need policies capable of effectively managing natural resource systems despite the fact that we understand them poorly at best. Real-World Management Issues. Real-world resource management must address three components: goal setting, practical (robust) implementation, and learning. Clark and others (Clark, 2007; 2006; Clark et al., 2006) have recently noted that practical implementation issues are frequently at the root of fishery management failures. For most fisheries, the necessary institutional contexts exist (Wilen, Homans) and we know what to do, yet management efforts fail. This suggests a need to focus on the actual process of resource management. For example, how can managers make decisions with incomplete information concerning how the resource and the resource users will respond to management actions? Design of Robust Policies for Uncertain Natural Resource Systems: Application to the Classic Gordon-Schaefer Fishery Model

Made available in DSpace on 2014-06-11T19:30:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-09Bitstream added on 2014-06-13T19:39:48Z : No. of bitstreams: 1 camara_atr_me_botfca.pdf: 536810 bytes, checksum: 57f5286522d61f84e18be56157805a7d (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Sementes recalcitrantes sempre apresentam dificuldades em seu armazenamento, tornandose um problema para produtores de mudas que muitas vezes não têm como realizar a semeadura logo após a colheita das sementes ou necessitam produzir mudas em diferentes épocas do ano, além de dificultar a conservação de germoplasma. As sementes de ingá, depois de colhidas, perdem sua viabilidade rapidamente, geralmente não ultrapassando 15 dias. As espécies de sementes recalcitrantes normalmente não utilizam bancos de sementes como estratégia de regeneração em condições naturais. Observações ecológicas têm mostrado que é mais comum sua regeneração natural ser por meio de bancos de plântulas. O objetivo do trabalho foi avaliar o armazenamento de sementes pré-germinadas de Inga vera Willd., provenientes de frutos em dois estádios diferentes de maturação, em três condições diferentes de umidade de substrato e em baixa temperatura. Os frutos de Inga vera Willd. colhidos foram separados em duas categorias, de acordo com sua coloração de casca, entre verdes e maduros. Após seu beneficiamento, as sementes foram prégerminadas e armazenadas em substrato sem adição de água (testemunha), com 30 e 60% de umidade sob baixa temperatura (10°C), por um ano. O armazenamento feito a 30 e 60% de umidade mostrou-se com melhor eficiência, tanto para plântulas provenientes de frutos verdes, como as de frutos maduros. Entre os dois tipos de frutos, observou-se que as plântulas obtidas de vagem verde, obtiveram melhor desempenho sob as condições de armazenamento, em relação àquelas obtidas de vagem madura. Podem ser armazenadas por até quatro meses, mantendo 50% de sobrevivência das plântulas do lote, quando o armazenamento é feito sob baixa temperatura (10 ± 5°C) e em substrato com 30 e 60% de umidade. Após um período de armazenamento... Recalcitrant seeds always present difficulties for storage procedures, becoming a problem for seedling producers that often have no choice to sow them immediately after seed harvest or when they need to produce seedlings through different times by the year. Inga seeds, once harvested, lose quickly their viability, often not exceeding a period of 15 days. Species of recalcitrant seeds do not use seed banks as regeneration strategy into the natural environment. Ecological observations have shown that is common occur their natural regeneration through seedling banks. The objective of this work was to evaluate pregerminated seed storage of Inga vera Willd. from two fruit maturation stages, under different conditions of substrate humidity, and under low temperature. The collected fruits of I. vera 9were splited into two types, according to their color, between unripe and ripe. After the processing of those seeds, they were pre-germinated on substrate and stored in substrate with no water addition (control), 30, and 60% humidity under low temperature (10°C) for a year. The storage made under 30 and 60% humidity showed to be the best for both, seedlings from unripe and ripe fruits. Between two types of fruits, we observed that the seedlings from unripe fruits, presented better performance under storage conditions, when compared to those obtained from mature fruits. They can be stored for until four months, with 50% of seedling survivals when stored under low temperature (10 ± 5°C) and with 30 and 60% of substrate humidity. After a year of seedling storage it was possible to get until 10% of survival... (Complete abstract click electronic access below)

An important feature of the GENESIS 3 simulator (G-3) is that its use is structured following an ideal user-workflow with a focus on actual experimental paradigms rather than the process of computational simulation by itself. This organization reflects the likely growing importance of linking models to real experiments and experimental data. As a consequence, the software architecture of the G-3 simulator allows it to be connected directly to independent databases that store models, experimental protocols, libraries of numerical solvers, repositories of results and aggregated analysis, and ultimately, tutorials and publications, as well as real time experimental protocols such as dynamic clamping procedures. In this paper, we present and explain the details of the database interfaces that support this functionality and show examples of data-driven modeling methods. The ideal user-workflow consists of 5 steps: (1) Construct model, (2) Design experiment, (3) Run simulation, (4) Check and analyze results, including experimentally, and (5) Iterate. In principle, each of these steps provides the foundation for databases that collectively define the scope and content of a modeling project. We provide three concrete and already implemented examples of the relationship between steps in the ideal user workflow and the databases that support them. 1. Construct Model: The G-3 software component that implements this first step in the ideal user workflow is called the Model-Container. It natively supports a dedicated data format (NDF) for computational models in neuroscience. The Model-Container has a built-in database of NDF models and also interfaces with arbitrary external model representations, including currently both NeuroML and NineML protocols. We show how to add new computational models to this database as well as how to interface to new model databases. 2. Design Experiment: The second step in the ideal user workflow connects the G-3 simulator to a database of generic experimental protocols such as current injection and current or voltage clamp. These protocols can be adjusted by a user to define specific experimental procedures. Note that these procedures are stored independently of the specification of the computational model, and can also, in principle, be obtained from any experimental source of data. We will demonstrate how the separation of the steps for model construction and experimental design allow, in principle, any model to be combined with any experimental procedure without requiring the procedure to be specifically designed for a given model. 3. Iterate: This final step in the ideal user workflow closes the loop between output of results and model construction. It can be used to define the differences in configuration between simulations belonging to the same simulation project, research project, educational tutorial or scientific publication. Further, this step can be automated in order to identify strengths, weaknesses, or deficits of a specific model. As such it becomes a powerful tool for pre-review of a model before its publication. In this presentation we will demonstrate how G-3 interfaces to a variety of existing databases which are accordingly then linked to model development and simulation. In principle this capability should accelerate a shift from purely procedural to data-driven modeling with important consequences for computational modelling methodology, and especially new forms of model publication and scientific communication.

Within this paper, control-relevant vehicle design concepts are examined using a widely used 3 DOF (plus flexibility) nonlinear model for the longitudinal dynamics of a generic carrot-shaped scramjet powered hypersonic vehicle. The impact of elevator size and placement on control-relevant static properties (e.g. level-flight trimmable region, trim controls, Angle of Attack (AOA), thrust margin) and dynamic properties (e.g. instability and right half plane zero associated with flight path angle) are examined. Elevator usage has been examine for a class of typical hypersonic trajectories.

This paper makes use of the direct heuristic dynamic programming design in a nonlinear tracking control setting with filtered tracking error. A Lyapunov stability approach is used for the stability analysis of the tracking system. It is shown that the closed-loop tracking error and the approximating neural network weight estimates retain the property of uniformly ultimate boundedness under the presence of neural network approximation error and bounded unknown disturbances under certain conditions.

Scramjet powered hypersonic vehicles represent the next critical step toward achieving NASA's vision for Highly Reliable Reusable Launch Systems (HRRLS), affordable space access, planetary re-entry systems, and global reach vehicles. The design of such vehicles is a very interdisciplinary and highly complex problem. As such, the development of varying fidelity mathematical models for assessing overall stability and performance during the design process is very important. In particular, developing “low-order” models with “sufficient fidelity” to capture control-centric phenomena becomes vital in early stages of vehicle design. Historically, the early stage vehicle design process never incorporated control related considerations. The design obtained by such practice is not optimal and can often lead to poor design from a stability and performance view point. This paper presents control-relevant modeling efforts which will facilitate quick iterative control analysis and design during early stages of vehicle design. The paper is intended to be of an introductory nature and presents the high level modeling framework and associated challenges. An example linear 6 DOF model with some representative analysis is also given to demonstrate the applicability of the tool suite.

A welded Zr-2.5%Nb plate with a texture similar to that of a CANDU* nuclear reactor pressure tube has been studied to determine the texture variations in the fusion zone and the heat affected zone (HAZ). The texture of the HAZ is explained by preferential growth of (001)[110] grains in the high-temperature bcc phase, with subsequent variant selection on cooling to enhance the volume fraction of (0002) normals perpendicular to the line of the weld. The same texture is observed in the fusion zone along with a (001)[100] texture component arising from solidification. The textures of the fusion zone and HAZ are not expected to increase the susceptibility of the welded plate to delayed hydride cracking.

O objetivo do trabalho foi identificar métodos para superar a dormência e promover a germinação de sementes de Stryphnodendron adstringens e Stryphnodendron polyphyllum. Sementes de ambas as espécies foram submetidas aos seguintes tratamentos de superação de dormência: testemunha, escarificação mecânica (lixa número 220), H2O quente (temperatura inicial de 87ºC) por 5 e por 15 minutos, escarificação química com H2SO4 (95%) por 30, 45, 60, 75, 90 e 105 minutos, choque térmico 1 (0ºC e 50% UR por 1h e após imersão em água por 10 min. Ti=85ºC Tf=57ºC), choque térmico 2 (40ºC e 40% UR por 6 h e após imersão em água por 10 min. Ti=0ºC Tf=3ºC), choque térmico 3 (40ºC e 40% UR por 6h e após imersão em água por 10 min Ti=25ºC Tf=25ºC). Conclui-se que sementes pertencentes ao mesmo gênero, mas de espécies diferentes, respondem de forma diversa a alguns tratamentos de superação de dormência. Para ambas as espécies, a escarificação das sementes com H2SO4 (45 minutos) ou lixa são métodos que podem ser utilizados com máxima eficiência para a superação da dormência e promoção da germinação. The aim of this research was to identify methods for breaking dormancy and promoting germination of Stryphnodendron adstringens and S. polyphyllum seeds. Seeds of both species were submitted to the following treatments for breaking dormancy: control; mechanical scarification (sandpaper number 220); hot water (initial temperature of 87°C) for 5 and 15 minutes; chemical scarification with H2SO4 (95%) for 30, 45, 60, 75, 90 and 105 minutes; thermal shock 1 (0°C and 50% RH for 1 h and thereafter 10 minutes into water Ti=85°C, Tf=57°C); thermic shock 2 (40°C and 40% RH for 6 h and thereafter 10 minutes into water, Ti=0°C, Tf=3°C); thermal shock 3 (40°C and 40% RH for 6h and thereafter 10 minutes into water, Ti=25°C, Tf=25°C). We concluded that seeds belonging to same genus but from different species answered differently to some treatments for breaking dormancy. Chemical scarification with H2SO4 (45 minutes) and mechanical scarification with sandpaper are methods that can be employed with efficiency to break dormancy and promote germination for both species.

The aim of this research was to identify methods for breaking dormancy and promoting germination of Stryphnodendron adstringens and S. polyphyllum seeds. Seeds of both species were submitted to the following treatments for breaking dormancy: control; mechanical scarification (sandpaper number 220); hot water (initial temperature of 87°C) for 5 and 15 minutes; chemical scarification with H2SO4 (95%) for 30, 45, 60, 75, 90 and 105 minutes; thermal shock 1 (0°C and 50%RH for 1h and thereafter 10 minutes into water Ti=85°C, Tf=57°C); thermic shock 2 (40°C and 40% RH for 6h and thereafter 10 minutes into water, Ti=0°C, Tf=3°C); thermal shock 3 (40°C and 40% RH for 6h and thereafter 10 minutes into water, Ti=25°C, Tf=25°C). We concluded that seeds belonging to same genus but from different species answered differently to some treatments for breaking dormancy. Chemical scarification with H2SO4 (45 minutes) and mechanical scarification with sandpaper are methods that can be employed with efficiency to break dormancy and promote germination for both species. O objetivo do trabalho foi identificar métodos para superar a dormência e promover a germinação de sementes de Stryphnodendron adstringens e Stryphnodendron polyphyllum. Sementes de ambas as espécies foram submetidas aos seguintes tratamentos de superação de dormência: testemunha, escarificação mecânica (lixa número 220), H2O quente (temperatura inicial de 87ºC) por 5 e por 15 minutos, escarificação química com H2SO4 (95%) por 30, 45, 60, 75, 90 e 105 minutos, choque térmico 1 (0ºC e 50%UR por 1h e após imersão em água por 10 min Ti=85oC Tf=57oC), choque térmico 2 (40ºC e 40%UR por 6h e após imersão em água por 10 min Ti=0ºC Tf=3ºC), choque térmico 3 (40ºC e 40%UR por 6h e após imersão em água por 10 min Ti=25ºC Tf=25ºC). Conclui-se que sementes pertencentes ao mesmo gênero, mas de espécies diferentes, respondem de forma diversa a alguns tratamentos de superação de dormência. Para ambas as espécies, a escarificação das sementes com H2SO4 (45 minutos) ou lixa são métodos que podem ser utilizados com máxima eficiência para a superação da dormência e promoção da germinação.

O objetivo do trabalho foi identificar métodos para superar a dormência e promover a germinação de sementes de Stryphnodendron adstringens e Stryphnodendron polyphyllum. Sementes de ambas as espécies foram submetidas aos seguintes tratamentos de superação de dormência: testemunha, escarificação mecânica (lixa número 220), H2O quente (temperatura inicial de 87ºC) por 5 e por 15 minutos, escarificação química com H2SO4 (95%) por 30, 45, 60, 75, 90 e 105 minutos, choque térmico 1 (0ºC e 50%UR por 1h e após imersão em água por 10 min Ti=85oC Tf=57oC), choque térmico 2 (40ºC e 40%UR por 6h e após imersão em água por 10 min Ti=0ºC Tf=3ºC), choque térmico 3 (40ºC e 40%UR por 6h e após imersão em água por 10 min Ti=25ºC Tf=25ºC). Conclui-se que sementes pertencentes ao mesmo gênero, mas de espécies diferentes, respondem de forma diversa a alguns tratamentos de superação de dormência. Para ambas as espécies, a escarificação das sementes com H2SO4 (45 minutos) ou lixa são métodos que podem ser utilizados com máxima eficiência para a superação da dormência e promoção da germinação.

Introduction The acute traumatic coagulopathy (ATC) which develops within 30 min following severe trauma with tissue damage and shock is defined by an increased prothrombin time (PT) and international normalized ratio (INR). While reduced thrombin might be expected in conjunction with elevated PT, recent clinical studies reveal paradoxically elevated thrombin generation potential in patients with ATC. We therefore hypothesized that the quantity of thrombin and the timing of thrombin-fibrinogen interactions both have an impact on clot quality; the exuberant production of thrombin found in trauma results in improper clot formation. Methods In vitro studies were conducted in human blood products and simplified synthetic plasma (consisting of purified human coagulation factors in HEPES buffered saline). Turbidimetry was used to observe fibrin crosslinking, while thromboelastography (TEG) was used to quantify clot formation parameters. Quantitation of fibrin(ogen) degradation products (FDPs) was conducted with the STA-R Evolution coagulation analyzer and by ELISA. A fluorogenic substrate was used to observe thrombin generation. Results Increasing the amount of prothrombin or thrombin (0-1400nM) in prothrombin-immunodepleted citrated plasma resulted in reduced clot times. The same dose response was examined in a buffered mixture of fibrinogen (300 mg/dl), FXIII (31.25nM), Ca2+ (2mM), and FXa (170nM-only used with prothrombin samples). However, while increasing prothrombin increased clot strength in both FII-deficient plasma and in the synthetic plasma, direct addition of thrombin decreased clot strength and by 3-fold at 1000nM versus 100nM (Figure 1; *p An examination of FDPs from plasmin-degraded fibrinogen ± thrombin ± FXIII showed that FDPs from both crosslinked and uncrosslinked fibrin had 4-fold higher amounts of fibrin monomer and D-dimer than those produced from plasmin digestion of pure fibrinogen. When FDPs from thrombin +fibrinogen ± FXIII were supplemented back into fresh fibrinogen (0-50% of the final mixture) and allowed to clot again, there was a concentration-dependent decrease in fibrin formation rate (control: 0.15 OD/min; 50% FDP: 0.07 OD/min; p Conclusions The dose responses of prothrombin versus thrombin reveal the significance of the timing of these reactions on proper clot formation. The conversion of prothrombin to thrombin mediated through FXa and FVa results in strong clots under normal circumstances. These results were reflected in both turbidimetry and TEG, indicating that fibrin crosslinking is being hindered by the presence of excess thrombin even in the presence of the antithrombin III. Additionally, FDPs from crosslinked substrates reduce new clot-making efficiency. Excess thrombin and significant increases in FDPs (which can result from fibrinolytic feedback loops) both contribute to an in vitro phenotype that may represent an underlying factor in the development of ATC. Disclosures No relevant conflicts of interest to declare.

Reactive oxygen species have been implicated as a cause of cancer and aging in mammals. Mice deficient for the antioxidant enzyme CuZn-superoxide dismutase (Sod1) have a decreased life span and an elevated incidence of liver cancer. To test the hypothesis that the cancer-prone phenotype in such mice is due to accelerated spontaneous mutation accumulation, we crossed these mutants with mice harboring a neutral lacZ mutation reporter gene. At 2 months of age, the lacZ mutation frequency in the liver of the hybrid animals was already twice as high as in littermate controls of the same age. This difference in mutation frequency increased to >3-fold at 6 months of age, after which it did not increase any further. Characterization of the mutation spectra in liver of the Sod1-null mice indicated mainly GC-to-TA transversions and GC-to-AT transitions, signature mutations of oxidative stress. The accelerated mutation accumulation in liver was accompanied by an increased frequency of apoptotic cells, as indicated by an increase in both terminal deoxyribonucleotidyl transferase–mediated dUTP nick end labeling– and caspase 3–stained cells at 6 and 12 months of age. In kidney, an elevated mutation frequency above controls of ∼2.5-fold was found not earlier than at 6 months. No increased mutation accumulation was observed in brain or spleen. These results support the hypothesis, that oxidative stress is an important causal factor of cancer in mammals. (Cancer Res 2005; 65(24): 11271-5)