2,225 research outputs found

    Water Management Strategies for Improved Coalbed Methane Production in the Black Warrior Basin

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    The modern coalbed methane industry was born in the Black Warrior Basin of Alabama and has to date produced more than 2.6 trillion cubic feet of gas and 1.6 billion barrels of water. The coalbed gas industry in this area is dependent on instream disposal of co-produced water, which ranges from nearly potable sodium-bicarbonate water to hypersaline sodium-chloride water. This study employed diverse analytical methods to characterize water chemistry in light of the regional geologic framework and to evaluate the full range of water management options for the Black Warrior coalbed methane industry. Results reveal strong interrelationships among regional geology, water chemistry, and gas chemistry. Coalbed methane is produced from multiple coal seams in Pennsylvanian-age strata of the Pottsville Coal Interval, in which water chemistry is influenced by a structurally controlled meteoric recharge area along the southeastern margin of the basin. The most important constituents of concern in the produced water include chlorides, ammonia compounds, and organic substances. Regional mapping and statistical analysis indicate that the concentrations of most ionic compounds, metallic substances, and nonmetallic substances correlate with total dissolved solids and chlorides. Gas is effectively produced at pipeline quality, and the only significant impurity is N{sub 2}. Geochemical analysis indicates that the gas is of mixed thermogenic-biogenic origin. Stable isotopic analysis of produced gas and calcite vein fills indicates that widespread late-stage microbial methanogenesis occurred primarily along a CO{sub 2} reduction metabolic pathway. Organic compounds in the produced water appear to have helped sustain microbial communities. Ammonia and ammonium levels increase with total dissolved solids content and appear to have played a role in late-stage microbial methanogenesis and the generation of N{sub 2}. Gas production tends to decline exponentially, whereas water production tends to decline hyperbolically. Hyperbolic decline indicates that water volume is of greatest concern early in the life of a coalbed methane project. Regional mapping indicates that gas production is controlled primarily by the ability to depressurize permeable coal seams that are natively within the steep part of the adsorption isotherm. Water production is greatest within the freshwater intrusion and below thick Cretaceous cover strata and is least in areas of underpressure. Water management strategies include instream disposal, which can be applied effectively in most parts of the basin. Deep disposal may be applicable locally, particularly where high salinity limits the ability to dispose into streams. Artificial wetlands show promise for the management of saline water, especially where the reservoir yield is limited. Beneficial use options include municipal water supply, agricultural use, and industrial use. The water may be of use to an inland shrimp farming industry, which is active around the southwestern coalbed methane fields. The best opportunities for beneficial use are reuse of water by the coalbed methane industry for drilling and hydraulic fracturing. This research has further highlighted opportunities for additional research on treatment efficiency, the origin of nitrogen compounds, organic geochemistry, biogenic gas generation, flow modeling, and computer simulation. Results of this study are being disseminated through a vigorous technology transfer program that includes web resources, numerous presentations to stakeholders, and a variety of technical publications

    Immune features that afford protection from clinical disease versus sterilizing immunity to Bordetella pertussis infection in a nonhuman primate model of whooping cough

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    The respiratory bacterial infection caused by Bordetella pertussis (whooping cough) is the only vaccine-preventable disease whose incidence has been increasing over the last 3 decades. To better understand the resurgence of this infection, a baboon animal model of pertussis infection has been developed. Naïve baboons that recover from experimental pertussis infection are resistant both to clinical disease and to airway colonization when re-challenged. In contrast, animals vaccinated with acellular pertussis vaccine and experimentally challenged do not develop disease, but airways remain colonized for 4-6 weeks. We explored the possibility that the IgG antibody response to pertussis infection is qualitatively different from antibodies induced by acellular pertussis vaccination. IgG was purified from pertussis-convalescent baboons shown to be resistant to pertussis disease and airway colonization. Purified IgG contained high titers to pertussis toxin, pertactin, and filamentous hemagglutinin. This pertussis-immune IgG or control IgG was passively transferred to naïve, juvenile baboons before experimental airway pertussis inoculation. The control animal that received normal IgG developed a typical symptomatic infection including leukocytosis, cough and airway colonization for 4 weeks. In contrast, baboons that received convalescent IgG maintained normal WBC counts and were asymptomatic. However, despite remaining asymptomatic, their airways were colonized for 4-6 weeks with B. pertussis. All animals developed IgG and IgA anti-pertussis antibody responses. Interestingly, the clearance of B. pertussis from airways coincided with the emergence of a serum anti-pertussis IgA response. These studies demonstrate that passive administration of pertussis-specific IgG from previously infected animals can prevent clinical disease but does not affect prolonged airway colonization with B. pertussis. This outcome is similar to that observed following acellular pertussis vaccination. Understanding immune mechanisms—other than IgG—that are capable of preventing airway colonization with B. pertussis will be critical for developing more effective vaccines to prevent whooping cough

    Effects of nintedanib in patients with limited cutaneous systemic sclerosis and interstitial lung disease

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    OBJECTIVES: To investigate the course of interstitial lung disease (ILD) and the effects of nintedanib in patients with limited cutaneous systemic sclerosis (lcSSc). METHODS: In the SENSCIS trial, patients with SSc-ILD were randomised to receive nintedanib or placebo. Patients who completed the SENSCIS trial were eligible to enter SENSCIS-ON, in which all patients received open-label nintedanib. RESULTS: Among 277 patients with lcSSc treated in the SENSCIS trial, the rate (SE) of decline in FVC (mL/year) over 52 weeks was -74.5 (19.2) in the placebo group and -49.1 (19.8) in the nintedanib group (difference: 25.3 [95% CI -28.9, 79.6]). Among 249 patients with data at week 52, mean (SE) changes in FVC at week 52 were -86.4 (21.1) mL in the placebo group and -39.1 (22.2) mL in the nintedanib group. Among 183 patients with lcSSc who participated in SENSCIS-ON and had data at week 52, mean (SE) changes in FVC from baseline to week 52 of SENSCIS-ON were -41.5 (24.0) mL in patients who took placebo in the SENSCIS trial and initiated nintedanib in SENSCIS-ON and -45.1 (19.1) mL in patients who took nintedanib in the SENSCIS trial and continued it in SENSCIS-ON. CONCLUSION: Patients with lcSSc may develop progressive fibrosing ILD. By targeting pulmonary fibrosis, nintedanib slows decline in lung function in patients with lcSSc and ILD. TRIAL REGISTRATION: ClinicalTrials.gov (https://www.clinicaltrials.gov), NCT02597933 and NCT03313180

    Assessment and detection of pain in noncommunicative severely brain-injured patients.

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    peer reviewedDetecting pain in severely brain-injured patients recovering from coma represents a real challenge. Patients with disorders of consciousness are unable to consistently or reliably communicate their feelings and potential perception of pain. However, recent studies suggest that patients in a minimally conscious state can experience pain to some extent. Pain monitoring in these patients is hence of medical and ethical importance. In this article, we will focus on the possible use of behavioral scales for the assessment and detection of pain in noncommunicative patients

    Solid malignancies among etanercept‐treated patients with granulomatosis with polyangiitis (Wegener's): Long‐term followup of a multicenter longitudinal cohort

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    Objective An association between therapeutic inhibition of tumor necrosis factor (TNF) and solid malignancies was observed during the Wegener's Granulomatosis Etanercept Trial (WGET), which included 180 patients with granulomatosis with polyangiitis (Wegener's) (GPA). The present study was conducted to determine the malignancy risk beyond the time of exposure to study therapy. Methods The occurrence and type of solid malignancies were ascertained using a standardized data form. Data collected included vital status, histologic findings, and therapeutic interventions. The Surveillance, Epidemiology, and End‐Results database was used to estimate a standardized incidence rate (SIR) for solid malignancies. Results Post‐trial followup data were available for 153 patients (85% of the original cohort), with a median followup time of 43 months. Fifty percent of these patients had received etanercept. There were no differences in demographic characteristics between the etanercept and placebo groups. Thirteen new solid malignancies were detected, 8 in the etanercept group and 5 in the placebo group. Compared to the general population, the risk of solid malignancies in the etanercept group was increased (SIR 3.92 [95% confidence interval 1.69–7.72]), but was not different from the risk in the placebo group compared to the general population (SIR 2.89 [95% confidence interval 0.94–6.73]). All solid malignancies occurred in patients who had been exposed to cyclophosphamide. The overall duration of disease and a history of malignancy before trial enrollment were associated with the development of malignancy during post‐trial followup. Conclusion The incidence of solid malignancy remained increased during long‐term followup of the WGET cohort. However, this could not be attributed solely to etanercept exposure during the trial. Anti‐TNF therapy with etanercept appears to further increase the risk of malignancy observed in patients with GPA treated with cytotoxic agents and should be avoided in these patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87143/1/30394_ftp.pd

    Ovarian reserve diminished by oral cyclophosphamide therapy for granulomatosis with polyangiitis (Wegener's)

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    Objective Standard treatment for severe granulomatosis with polyangiitis (Wegener's) (GPA) is daily oral cyclophosphamide (CYC), a cytotoxic agent associated with ovarian failure. In this study, we assessed the rate of diminished ovarian reserve in women with GPA who received CYC versus methotrexate (MTX). Methods Patients in the Wegener's Granulomatosis Etanercept Trial received either daily CYC or weekly MTX and were randomized to etanercept or placebo. For all women ages <50 years, plasma samples taken at baseline or early in the study were evaluated against samples taken later in the study to compare levels of anti‐Müllerian hormone (AMH) and follicle‐stimulating hormone (FSH), endocrine markers of remaining egg supply. Diminished ovarian reserve was defined as an AMH level of <1.0 ng/ml. Results Of 42 women in this analysis (mean age 35 years), 24 had CYC exposure prior to enrollment and 28 received the drug during the study. At study entry, women with prior CYC exposure had significantly lower AMH, higher FSH, and a higher rate of early menstruation cessation. For women with normal baseline ovarian function, 6 of 8 who received CYC during the trial developed diminished ovarian reserve, compared to 0 of 4 who did not receive CYC ( P < 0.05). Changes in AMH correlated inversely with cumulative CYC dose ( P < 0.01), with a 0.74 ng/ml decline in AMH level for each 10 gm of CYC. Conclusion Daily oral CYC, even when administered for less than 6 months, causes diminished ovarian reserve, as indicated by low AMH levels. These data highlight the need for alternative treatments for GPA in women of childbearing age.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88079/1/20605_ftp.pd

    Association of Pulmonary Hemorrhage, Positive Proteinase 3, and Urinary Red Blood Cell Casts With Venous Thromboembolism in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

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    Objective To assess the frequency of venous thromboembolism (VTE) events in the Rituximab in Antineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis (RAVE) trial and identify novel potential risk factors. Methods VTE events in 197 patients enrolled in the RAVE trial were analyzed. Baseline demographic and clinical characteristics were recorded, and univariate and multivariate analyses were performed to identify factors associated with VTE in ANCA-associated vasculitis (AAV). Results VTE occurred in 16 patients (8.1%) with an overall average time to event of 1.5 months (range 1.0-2.75). In univariate analyses with calculation of hazard ratios (HRs) and 95% confidence intervals (95% CIs), heart involvement (HR 17.408 [95% CI 2.247-134.842]; P = 0.006), positive proteinase 3 (PR3)-ANCA (HR 7.731 [95% CI 1.021-58.545]; P = 0.048), pulmonary hemorrhage (HR 3.889 [95% CI 1.448-10.448]; P = 0.008), and the presence of red blood cell casts (HR 15.617 [95% CI 3.491-69.854]; P <0.001) were associated with the onset of VTE. In multivariate models adjusted for age and sex, the significant associations between VTE events and heart involvement (HR 21.836 [95% CI 2.566-185.805]; P = 0.005), PR3-ANCA (HR 9.12 [95% CI 1.158-71.839]; P = 0.036), pulmonary hemorrhage (HR 3.91 [95% CI 1.453-10.522]; P = 0.007), and urinary red blood cell casts (HR 16.455 [95% CI 3.607-75.075]; P <0.001) remained. Conclusion Patients diagnosed as having AAV with pulmonary hemorrhage, positive PR3-ANCA, heart involvement, and the presence of red blood cell casts are at an increased risk to develop VTE. Further studies are needed to confirm and expand these findings and to explore the mechanisms of hypercoagulability in these patients with the aim of informing potential targets for therapeutic intervention

    Three-dimensional anisotropic pressure free boundary equilibria

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    Free boundary three-dimensional anisotropic pressure magnetohydrodynamic equilibria with nested magnetic flux surfaces are computed through the minimisation of the plasma energy functional W=Vd3x[B2/(2μ0)+p/(Γ1)]W={\int}_{V}{d^3}x\left[{B^2}/(2\mu_0)+p_{||}/(\Gamma-1)\right]. The plasma–vacuum interface is varied to guarantee the continuity of the total pressure [p+B2/(2μ0)]\left[{p}_{\perp}+{B^2}/(2\mu_0)\right] across it and the vacuum magnetic field must satisfy the Neumann boundary condition that its component normal to this interface surface vanishes. The vacuum magnetic field corresponds to that driven by the plasma current and external coils plus the gradient of a potential function whose solution is obtained using a Green's function method. The energetic particle contributions to the pressure are evaluated analytically from the moments of the variant of a bi-Maxwellian distribution function that satisfies the constraint BFh=0{\bf B\cdot\nabla}{\cal F}_h=0. Applications to demonstrate the versatility and reliability of the numerical method employed have concentrated on high-β off-axis energetic particle deposition with large parallel and perpendicular pressure anisotropies in a 2-field period quasiaxisymmetric stellarator reactor system. For large perpendicular pressure anisotropy, the hot particle component of the pperpendicular distribution localises in the regions where the energetic particles are deposited. For large parallel pressure anisotropy, the pressures are more uniform around the flux surfaces
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