600 research outputs found

    Removal of acid gases and oxides of nitrogen from space cabin atmospheres

    Get PDF
    Removal of acid gases and oxides of nitrogen from spacecraft cabin atmospheres at ambient temperature

    Life history and population dynamics of the finetooth shark (Carcharhinus isodon) in the northeastern Gulf of Mexico

    Get PDF
    The life history and population dynamics of the finetooth shark (Carcharhinus isodon) in the north-eastern Gulf of Mexico were studied by determining age, growth, size-at-maturity, natural mortality, productivity, and elasticity of vital rates of the population. The von Bertalanffy growth model was estimated as Lt=1559 mm TL (1–e–0.24 (t+2.07)) for females and Lt = 1337 mm TL (1–e–0.41 (t+1.39)) for males. For comparison, the Fabens growth equation was also fitted separately to observed size-at-age data, and the fits to the data were found to be similar. The oldest aged specimens were 8.0 and 8.1 yr, and theoretical longevity estimates were 14.4 and 8.5 yr for females and males, respectively. Median length at maturity was 1187 and 1230 mm TL, equivalent to 3.9 and 4.3 yr for males and females, respectively. Two scenarios, based on the results of the two equations used to describe growth, were considered for population modeling and the results were similar. Annual rates of survivorship estimated through five methods ranged from 0.850/yr to 0.607/yr for scenario 1 and from 0.840/yr to 0.590/yr for scenario 2. Productivities were 0.041/yr for scenario 1 and 0.038/yr for scenario 2 when the population level that produces maximum sustain-able yield is assumed to occur at an instantaneous total mortality rate (Z) equaling 1.5 M, and were 0.071/yr and 0.067/yr, when Z=2 M for scenario 1 and 2, respectively. Mean generation time was 6.96 yr and 6.34 yr for scenarios 1 and 2, respectively. Elasticities calculated through simulation of Leslie matrices averaged 12.6% (12.1% for scenario 2) for fertility, 47.7% (46.2% for scenario 2) for juvenile survival, and 39.7% (41.6% for scenario 2) for adult survival. In all, the finetooth shark exhibits life-history and population characteristics intermediate to those of sharks in the small coastal complex and those from some large coastal species, such as the blacktip shark (Carcharhinus limbatus)

    Characterization of Men with Hemophilia B and Factors Associated with Treatment Practices, Participating in the Community Counts Registry from 2014 to 2018.

    Get PDF
    Hemophilia B is an inherited, X-linked, bleeding disorder caused by a mutation of the clotting factor 9 (FIX) gene. The mutation reduces the amount of FIX protein and results in spontaneous and trauma-related bleeding episodes. In 1994, approximately 2,800 men with hemophilia B (MWHB) were treated at hemophilia treatment centers (HTCs) in the United States (US). To date, studies examining health outcomes for MWHB in the US have not been compared across disease severities. Treatment of MWHB has become more complex with changes in prophylaxis practices in the US and the introduction of novel treatment products. Observational studies that describe health outcomes among MWHB and current treatment practices are important to inform future clinical practices. These cross-sectional analyses used data from MWHB enrolled in the Community Counts surveillance Registry (Registry) from 2014 to 2018. The first paper compared the sample of MWHB in the Registry to the population of MWHB who received treatment in HTCs and described the demographic, clinical factors, and health outcomes across disease severities. From 2014-2018, the population of MWHB who received care in HTCs included 4,816 MWHB, of which 2091 participated in the Registry. The second paper examined demographic, clinical factors, and health outcomes associated with treatment regimen, prophylaxis versus episodic; and used a marginal model. The final model included ethnicity, health insurance, history of a joint bleed, and interactions between severity by chronic pain as well as age by history of central venous access device utilization. The third paper examined demographic, clinical factors, and health outcomes associated with treatment product type utilization, standard half-life products versus extended half-life products, among MWHB on continuous prophylaxis; and used a marginal model. The final model included disease severity, enrollment year, HTC region, and percent of missed treatment dose. The second and third paper demonstrated that patient-level treatment outcomes were clustered by the HTCs where they received care. Future studies should examine the treatment dosage and frequency of administration of treatment products for MWHB on prophylaxis and replicate these studies for hemophilia A to determine if the factors associated with treatment are similar for all men with hemophilia

    Period-Luminosity Relations Derived from the OGLE-III Fundamental Mode Cepheids

    Full text link
    In this Paper, we have derived Cepheid period-luminosity (P-L) relations for the Large Magellanic Cloud (LMC) fundamental mode Cepheids, based on the data released from OGLE-III. We have applied an extinction map to correct for the extinction of these Cepheids. In addition to the VIW band P-L relations, we also include JHK and four Spitzer IRAC band P-L relations, derived by matching the OGLE-III Cepheids to the 2MASS and SAGE datasets, respectively. We also test the non-linearity of the Cepheid P-L relations based on extinction-corrected data. Our results (again) show that the LMC P-L relations are non-linear in VIJH bands and linear in KW and the four IRAC bands, respectively.Comment: 6 pages, 3 figures and 3 tables, ApJ accepte

    Inflammation and oxidative stress in multiple sclerosis:Consequences for therapy development

    Get PDF
    CNS inflammation is a major driver of MS pathology. Differential immune responses, including the adaptive and the innate immune system, are observed at various stages of MS and drive disease development and progression. Next to these immune-mediated mechanisms, other mediators contribute to MS pathology. These include immune-independent cell death of oligodendrocytes and neurons as well as oxidative stress-induced tissue damage. In particular, the complex influence of oxidative stress on inflammation and vice versa makes therapeutic interference complex. All approved MS therapeutics work by modulating the autoimmune response. However, despite substantial developments in the treatment of the relapsing-remitting form of MS, approved therapies for the progressive forms of MS as well as for MS-associated concomitants are limited and much needed. Here, we summarize the contribution of inflammation and oxidative stress to MS pathology and discuss consequences for MS therapy development

    Intake of Lycopene and other Carotenoids and Incidence of Uterine Leiomyomata: A Prospective Ultrasound Study

    Get PDF
    BACKGROUND: Uterine leiomyomata (UL) are the leading indication for hysterectomy in the United States. Dietary supplementation with lycopene was associated with reduced size and incidence of oviduct leiomyoma in the Japanese quail. Two US prospective cohort studies of women reported little association between intake of lycopene, or other carotenoids, and UL incidence. However, these studies relied on self-reported physician-diagnosed UL, which is prone to misclassification. OBJECTIVE: This study examines the association between dietary intake of carotenoids and UL incidence. DESIGN: Data were derived from the Study of the Environment, Lifestyle, and Fibroids, a prospective cohort study. Women completed self-administered baseline questionnaires on demographic characteristics, reproductive history, and lifestyle, including a 110-item validated food frequency questionnaire, from which dietary intakes of carotenoids-including alpha carotene, beta carotene, cryptoxanthin, lutein-zeaxanthin, and lycopene-and vitamin A were estimated. PARTICIPANTS/SETTING: One thousand two hundred thirty Black women aged 23 to 35 years who did not have a previous diagnosis of UL, cancer, or autoimmune disease were eligible for enrollment (2010-2012). Participants were residents of the Detroit, MI, metropolitan area. MAIN OUTCOME MEASURES: Transvaginal ultrasound was used to assess UL at baseline and 20, 40, and 60 months of follow-up. STATISTICAL ANALYSES PERFORMED: Cox regression was used to estimate hazard ratios and 95% CIs, adjusted for energy intake, age at menarche, education, body mass index, parity, age at first birth, years since last birth, current use of oral contraceptives or progestin-only injectables, alcohol intake, and cigarette smoking. RESULTS: Among 1,230 women without prevalent UL at baseline, 301 incident UL cases during follow-up were identified. Intakes of lycopene, other carotenoids, and vitamin A were not appreciably associated with UL incidence. Hazard ratios comparing quartiles 2 (2,376 to 3,397 μg/day), 3 (3,398 to 4,817 μg/day), and 4 (≥4,818 μg/day) with quartile 1 (\u3c2,376 μg/day) of lycopene intake were 1.03 (95% CI 0.72 to 1.47), 1.22 (95% CI 0.86 to 1.72), and 0.95 (95% CI 0.67 to 1.36), respectively. CONCLUSIONS: Study findings do not support the hypothesis that greater carotenoid intake is associated with reduced UL incidence

    Hybrid Equation/Agent-Based Model of Ischemia-Induced Hyperemia and Pressure Ulcer Formation Predicts Greater Propensity to Ulcerate in Subjects with Spinal Cord Injury

    Get PDF
    Pressure ulcers are costly and life-threatening complications for people with spinal cord injury (SCI). People with SCI also exhibit differential blood flow properties in non-ulcerated skin. We hypothesized that a computer simulation of the pressure ulcer formation process, informed by data regarding skin blood flow and reactive hyperemia in response to pressure, could provide insights into the pathogenesis and effective treatment of post-SCI pressure ulcers. Agent-Based Models (ABM) are useful in settings such as pressure ulcers, in which spatial realism is important. Ordinary Differential Equation-based (ODE) models are useful when modeling physiological phenomena such as reactive hyperemia. Accordingly, we constructed a hybrid model that combines ODEs related to blood flow along with an ABM of skin injury, inflammation, and ulcer formation. The relationship between pressure and the course of ulcer formation, as well as several other important characteristic patterns of pressure ulcer formation, was demonstrated in this model. The ODE portion of this model was calibrated to data related to blood flow following experimental pressure responses in non-injured human subjects or to data from people with SCI. This model predicted a higher propensity to form ulcers in response to pressure in people with SCI vs. non-injured control subjects, and thus may serve as novel diagnostic platform for post-SCI ulcer formation. © 2013 Solovyev et al

    Effects of local hypothermia-rewarming on physiology, metabolism and inflammation of acutely injured human spinal cord.

    Get PDF
    In five patients with acute, severe thoracic traumatic spinal cord injuries (TSCIs), American spinal injuries association Impairment Scale (AIS) grades A-C, we induced cord hypothermia (33 °C) then rewarming (37 °C). A pressure probe and a microdialysis catheter were placed intradurally at the injury site to monitor intraspinal pressure (ISP), spinal cord perfusion pressure (SCPP), tissue metabolism and inflammation. Cord hypothermia-rewarming, applied to awake patients, did not cause discomfort or neurological deterioration. Cooling did not affect cord physiology (ISP, SCPP), but markedly altered cord metabolism (increased glucose, lactate, lactate/pyruvate ratio (LPR), glutamate; decreased glycerol) and markedly reduced cord inflammation (reduced IL1β, IL8, MCP, MIP1α, MIP1β). Compared with pre-cooling baseline, rewarming was associated with significantly worse cord physiology (increased ICP, decreased SCPP), cord metabolism (increased lactate, LPR; decreased glucose, glycerol) and cord inflammation (increased IL1β, IL8, IL4, IL10, MCP, MIP1α). The study was terminated because three patients developed delayed wound infections. At 18-months, two patients improved and three stayed the same. We conclude that, after TSCI, hypothermia is potentially beneficial by reducing cord inflammation, though after rewarming these benefits are lost due to increases in cord swelling, ischemia and inflammation. We thus urge caution when using hypothermia-rewarming therapeutically in TSCI
    • …
    corecore