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Noble gas transport through geologic media has important applications in the characterization of underground nuclear explosions (UNEs). Without accurate transport models, it is nearly impossible to distinguish between xenon signatures originating from civilian nuclear facilities and UNEs. Understanding xenon transport time through the earth is a key parameter for interpreting measured xenon isotopic ratios. One of the most challenging aspects of modeling gas transport time is accounting for the effect of variable water saturation of geological media. In this study, we utilize bench-scale laboratory experiments to characterize the diffusion of krypton, xenon, and sulfur hexafluoride (SF6) through intact zeolitic tuff under different saturations. We demonstrate that the water in rock cores with low partial saturation dramatically affects xenon transport time compared to that of krypton and SF6 by blocking sites in zeolitic tuff that preferentially adsorb xenon. This leads to breakthrough trends that are strongly influenced by the degree of the rock saturation. Xenon is especially susceptible to this phenomenon, a finding that is crucial to incorporate in subsurface gas transport models used for nuclear event identification. We also find that the breakthrough of SF6 diverges significantly from that of noble gases within our system. When developing field scale models, it is important to understand how the behavior of xenon deviates from chemical tracers used in the field, such as SF6 (Carrigan et al., 1996). These new insights demonstrate the critical need to consider the interplay between rock saturation and fission product sorption during transport modeling, and the importance of evaluating specific interactions between geomedia and gases of interest, which may differ from geomedia interactions with chemical tracers.

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An underground nuclear explosion (UNE) generates radioactive gases that can be transported through fractures to the ground surface over timescales of hours to months. If detected, the presence of particular short-lived radionuclides in the gas can provide strong evidence that a recent UNE has occurred. By drawing comparisons between sixteen similar historical U.S. UNEs where radioactive gas was or was not detected, we identified factors that control the occurrence and timing of breakthrough at the ground surface. The factors that we evaluated include the post-test atmospheric conditions, local geology, and surface geology at the UNE sites. The UNEs, all located on Pahute Mesa on the Nevada National Security Site (NNSS), had the same announced yield range (20-150 kt), similar burial depths in the unsaturated zone, and were designed and performed by the same organization during the mid-to-late 1980s. Results of the analysis indicate that breakthrough at the ground surface is largely controlled by a combination of the post-UNE barometric pressure changes in the months following the UNE, and the volume of air-filled pore space above the UNE. Conceptually simplified numerical models of each of the 16 historical UNEs that include these factors successfully predict the occurrence (5 of the UNEs) or lack of occurrence (remaining 11 UNEs) of post-UNE gas seepage to the ground surface. However, the data analysis and modeling indicates that estimates of the meteorological conditions and of the post-UNE, site-specific subsurface environment including air-filled porosity, in combination, may be necessary to successfully predict late-time detectable gas breakthrough for a suspected UNE site.

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Identifying differential responses between sexes following traumatic brain injury (TBI) can elucidate the mechanisms behind disease pathology. Peripheral and central inflammation in the pathophysiology of TBI can increase sleep in male rodents, but this remains untested in females. We hypothesized that diffuse TBI would increase inflammation and sleep in males more so than in females. Diffuse TBI was induced in C57BL/6J mice and serial blood samples were collected (baseline, 1, 5, 7 days post-injury [DPI]) to quantify peripheral immune cell populations and sleep regulatory cytokines. Brains and spleens were harvested at 7DPI to quantify central and peripheral immune cells, respectively. Mixed-effects regression models were used for data analysis. Female TBI mice had 77%-124% higher IL-6 levels than male TBI mice at 1 and 5DPI, whereas IL-1ß and TNF-α levels were similar between sexes at all timepoints. Despite baseline sex differences in blood-measured Ly6Chigh monocytes (females had 40% more than males), TBI reduced monocytes by 67% in TBI mice at 1DPI. Male TBI mice had 31%-33% more blood-measured and 31% more spleen-measured Ly6G+ neutrophils than female TBI mice at 1 and 5DPI, and 7DPI, respectively. Compared with sham, TBI increased sleep in both sexes during the first light and dark cycles. Male TBI mice slept 11%-17% more than female TBI mice, depending on the cycle. Thus, sex and TBI interactions may alter the peripheral inflammation profile and sleep patterns, which might explain discrepancies in disease progression based on sex.

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We demonstrate that although barometric pressures are complicated signals comprised of numerous frequencies, it is a subset of these frequencies that drive the overwhelming majority of gas transport in fractured rock. Using an inverse numerical analysis, we demonstrate that a single barometric component with seasonally modulated amplitude approximates gas transport due to a measured barometric signal. If past barometric tendencies are expected to continue at a location, the identification of this frequency can facilitate accurate long term predictions of barometrically induced gas transport negating the need to consider stochastic realizations of future barometric variations. Additionally, we perform an analytical analysis that indicates that there is a set of barometric frequencies, consistent with the inverse numerical analysis, with high production efficiency. Based on the corroborating inverse numerical and analytical analyses, we conclude that there is a set of dominant gas transport frequencies in barometric records.

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We used hydrogeologic models to assess how fault-zone properties promote or inhibit the downward propagation of fluid overpressures from a basal reservoir injection well (150 m from fault zone, Q = 5000 m3 /day) into the underlying crystalline basement rocks. We varied the permeability of the fault-zone architectural components and a crystalline basement weathered layer as part of a numerical sensitivity study. Realistic conduit-barrier style fault zones effectively transmit elevated pore pressures associated with 4 years of continuous injection to depths of approximately 2.5 km within the crystalline basement while compartmentalizing fluid flow within the injection reservoir. The presence of a laterally continuous, relatively low-permeability altered/weathered basement horizon (kaltered layer = 0.1 × kbasement ) can limit the penetration depth of the pressure front to approximately 500 m. On the other hand, the presence of a discontinuous altered/weathered horizon that partially confines the injection reservoir without blocking the fault fluid conduit promotes downward propagation of pressures. Permeability enhancement via hydromechanical failure was found to increase the depth of early-time pressure front migration by a factor of 1.3 to 1.85. Dynamic permeability models may help explain seismicity at depths of greater than 10 km such as is observed within the Permian Basin, NM.

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Introducción: trabajadores que realizan mantenimiento en alcantarillados se exponen a riesgos disergonomicos que pueden desencadenar patologías osteomusculares. Métodos: estudio descriptivo, con fuente primaria de información, previa obtención de consentimiento informado a un censo de trabajadores (43) que realizan labores de mantenimiento en una empresa de servicios públicos de Colombia. Se exploraron variables socio-demográficas, económicas, de salud y laborales. El riesgo ergonómico fue evaluado con el cuestionario RULA. Se realizaron análisis descriptivos y de asociación, con una confianza del 95% y error del 5%. Resultados: trabajadores con 43 años (±12 años), 44,2% eran oficiales de mantenimiento de aguas, con peso normal y sobre peso, prevalencia de diabetes 5,1%, artrosis y lesión de tejidos blandos 12,5%, fumadores activos un 12,8% y 37,2% con dolor en miembros superiores. El 86,0% realizaba labores que requieren cambios urgentes, 25,6% con diagnóstico de síndrome del manguito de rotadores y 7,0% manguito de rotadores y epicondilitis lateral y/o medial de codo. Aumento de desórdenes musculo esqueléticos con el aumento del tiempo de labor, haber tenido cirugía de hombro o antecedentes de accidentes en hombro y mayor edad. Conclusiones: se evidencia la necesidad de adelantar acciones preventivas y correctivas en la población de estudio, características como el tiempo en su oficio, la labor que se desempeña y la edad, se asocian con mayor riesgo de desórdenes musculoesqueléticos

Introduction: workers who perform maintenance in sewage systems are exposed to disergonomic risks that can trigger osteomuscular diseases. Methods: a descriptive study, with a primary source of information, after obtaining informed consent to a census of workers (43) who perform maintenance tasks in a public utility company in Colombia. Socio-demographic, economic, health and labor variables were explored. The ergonomic risk was evaluated with the RULA questionnaire. Descriptive and association analyzes were performed, with 95% confidence and 5% error. Results: of te workers aged 43 (± 12 years), 44.2% were water maintenance officers, with normal weight and overweight, prevalence of diabetes 5.1%, osteoarthritis and soft tissue injury 12.5%, active smokers 12.8% and 37.2% with pain in upper limbs. 86.0% performed tasks requiring urgent changes, 25.6% with a diagnosis of rotator cuff and 7.0% rotator cuff and lateral and/or medial elbow epicondylitis. The increase of musculoskeletal disorders with increased labor time, was associated to having had shoulder surgery or a history of shoulder accidents and older age. Conclusions: there is evidence of the need to carry out preventive and corrective actions in the study population, characteristics such as time in office, the work performed and age, are associated with increased risk of musculoskeletal disorders

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There is a considerable controversy about whether western Amazonia was ever covered by marine waters during the Miocene [23 to 5 Ma (million years ago)]. We investigated the possible occurrence of Miocene marine incursions in the Llanos and Amazonas/Solimões basins, using sedimentological and palynological data from two sediment cores taken in eastern Colombia and northwestern Brazil together with seismic information. We observed two distinct marine intervals in the Llanos Basin, an early Miocene that lasted ~0.9 My (million years) (18.1 to 17.2 Ma) and a middle Miocene that lasted ~3.7 My (16.1 to 12.4 Ma). These two marine intervals are also seen in Amazonas/Solimões Basin (northwestern Amazonia) but were much shorter in duration, ~0.2 My (18.0 to 17.8 Ma) and ~0.4 My (14.1 to 13.7 Ma), respectively. Our results indicate that shallow marine waters covered the region at least twice during the Miocene, but the events were short-lived, rather than a continuous full-marine occupancy of Amazonian landscape over millions of years.

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La distribución geográfica del carcinoma hepatocelular (CHC) depende de la incidencia y prevalencia de sus agentes etiológicos en los diferentes lugares. Esto ha llevado a la realización de un mapa que muchas veces puede coincidir con las características de dichas entidades causales; las más importantes son la hepatitis B, la hepatitis C e incluso el alcohol en algunas regiones del mundo. Las estadísticas informadas en cuanto a raza, edad y sexo también dependen mucho de estas causas, y por eso en algunos casos los datos pueden ser similares, pero bien vale la pena recordarlos.

The geographical distribution of hepatocellular carcinoma (HCC) depends on the incidence and prevalence of related etiological agents in different places. This has led to the creation of a map upon which the characteristics of these causal entities can often be matched. The most important are hepatitis B, hepatitis C and even alcohol in some regions. The statistics are also reported in terms of race, age and sex and are heavily relied upon in these cases as well. In some cases the data may be similar which is well worth remembering.

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La hepatitis autoinmune es una entidad que se puede presentar en forma asintomática, como hepatitis aguda o como cirrosis hepática; el diagnóstico se basa en criterios clínicos, de laboratorio basados en niveles elevados de inmunoglobulina G y autoanticuerpos y en criterios histológicos como la hepatitis de interfase, la presencia de células plasmáticas e infiltrado linfocitario, en casos de difícil diagnóstico se pueden utilizar los sistemas de puntuación original o modificado. El tratamiento se basa en la utilización de inmunosupresores como corticoides y azatioprina que cambiaron la historia natural de la enfermedad.

Autoimmune hepatitis is a condition which can be asymptomatic or can present as acute hepatitis or liver cirrhosis. Diagnosis is based on clinical criteria and laboratory criteria. Laboratory criteria include elevated levels of immunoglobulin G and/or autoantibodies and histological criteria such as hepatitis interface, the presence of plasma cells and lymphocytic infiltrate. In difficult to diagnose cases original or modified scoring systems can be used. Treatment is based on the use of immunosuppressants such as corticosteroids and azathioprine that have changed the natural history of disease.

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A hospital that is seeking ways to cut costs without compromising care should resist the temptation to lay off staff and instead make it a priority to improve efficiencies. This approach requires a formal program to identify and analyze all of the hospital's processes. The focus of the analysis should be to determine which activities are being performed efficiently, which are being performed inefficiently, and which are unnecessary. This effort will achieve the greatest success if it is customer-centric.

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