Biodegradation of Dichloromethane and Its Utilization as a Growth Substrate under Methanogenic Conditions

Biodegradation of dichloromethane (DCM) to environmentally acceptable products was demonstrated under methanogenic conditions (35 degrees C). When DCM was supplied to enrichment cultures as the sole organic compound at a low enough concentration to avoid inhibition of methanogenesis, the molar ratio of CH4 formed to DCM consumed (0.473) was very close to the amount predicted by stoichiometric conservation of electrons. DCM degradation was also demonstrated when methanogenesis was partially inhibited (with 0.5 to 1.5 mM 2-bromoethanesulfonate or approximately 2 mM DCM) or completely stopped (with 50 to 55.5 mM 2-bromoethanesulfonate). Addition of a eubacterial inhibitor (vancomycin, 100 mg/liter) greatly reduced the rate of DCM degradation. 14CO2 was the principal product of [14C]DCM degradation, followed by 14CH4 (when methanogenesis was uninhibited) or 14CH3COOH (when methanogenesis was partially or completely inhibited). Hydrogen accumulated during DCM degradation and then returned to background levels when DCM was consumed. These results suggested that nonmethanogenic organisms mediated DCM degradation, oxidizing a portion to CO2 and fermenting the remainder to acetate; acetate formation suggested involvement of an acetogen. Methanogens in the enrichment culture then converted the products of DCM degradation to CH4. Aceticlastic methanogens were more easily inhibited by 2-bromoethanesulfonate and DCM than were CO2-reducing methanogens. When DCM was the sole organic-carbon and electron donor source supplied, its use as a growth substrate was demonstrated. The highest observed yield was 0.085 g of suspended organic carbon formed per g of DCM carbon consumed. Approximately 85% of the biomass formed was attributable to the growth of nonmethanogens, and 15% was attributable to methanogens

The use of an aircraft test stand for VTOL handling qualities studies

The VTOL flight tests stand for testing control concepts on the X-14B VSS aircraft in hover, is described. This stand permits realistic and safe piloted evaluation and checkout of various control systems and of parameter variations within each system to determine acceptability to the pilot. Pilots can use it as a practical training tool to practice procedures and flying techniques and become familiar with the aircraft characteristics. Some examples of test experience are given. The test stand allows the X14B to maneuver in hover from centered position + or - 9.7 deg in roll and + or - 9.3 deg in pitch, about + or - 6 deg in yaw, and + or - 15 cm in vertical translation. The unique vertical free flight freedom enables study of liftoffs and landings with power conditions duplicated. The response on the stand agrees well with that measured in free hovering flight, and pilot comments confirm this

Total anomalous pulmonary venous connection: Results of surgical repair of 100 patients at a single institution

ObjectiveSurgical repair of total anomalous pulmonary venous connection is associated with significant mortality and morbidity, especially in patients with single-ventricle physiology. This study analyzes total anomalous pulmonary venous connection surgical repair results at one institution to identify trends and indicators of positive outcome.MethodsOur cardiac surgery database identified 100 patients undergoing surgical repair of total anomalous pulmonary venous connection (1990–2008): supracardiac (52), cardiac (15), infracardiac (23), and mixed (10). The median age at repair was 14.6 days (range, 0–4 years), and the median weight was 3.5 kg (range, 1.3–15 kg). Patients were divided into 2 groups: biventricular (n = 83) or single-ventricle (n = 17) physiology. All but 1 of the patients with single-ventricle physiology had heterotaxy syndrome (94%), and 13 of 17 patients had supracardiac anatomy.ResultsThere were 12 operative deaths (4 in the biventricular group [5%] and 8 in the single-ventricle group [47%], P < .01) and 9 late deaths (6 in the biventricular group [7%] and 3 in the single-ventricle group [18%], P < .05). Death by total anomalous pulmonary venous connection type was supracardiac (12/52; 23.1%), cardiac (1/15; 6.7%), infracardiac (3/23; 13.0%), and mixed (5/10; 50%). Pulmonary venous obstruction was present in 22 patients in the biventricular group (27%) and in 7 patients in the single-ventricle group (41%; P = .25). Mortality was 9 of 29 (31%) in those with pulmonary venous obstruction and 12 of 71 (17%) in those with nonpulmonary venous obstruction (P = .23). Deep hypothermic circulatory arrest was used in 38 patients (27 in the biventricular group, 32.5%; 11 in the single-ventricle group, 64.7%). Mean deep hypothermic circulatory arrest time was 31.4 ± 10.7 minutes (P = not significant between groups). Median postoperative length of stay was 11 days (range, 0–281 days). Nineteen patients required reoperation for pulmonary venous stenosis (14 in the biventricular group and 5 in the single-ventricle group. P = .045); the median time to reoperation was 104 days (range, 4–753 days).ConclusionPatients with total anomalous pulmonary venous connection with biventricular anatomy have good outcomes. Patients with single-ventricle anatomy have higher mortality and increased risk for pulmonary vein stenosis requiring reoperation. Mortality is highest in patients with mixed-type total anomalous pulmonary venous connection

Radial Flow in Au+Au Collisions at E=0.25-1.15 A GeV

A systematic study of energy spectra for light particles emitted at midrapidity from Au+Au collisions at E=0.25-1.15 A GeV reveals a significant non-thermal component consistent with a collective radial flow. This component is evaluated as a function of bombarding energy and event centrality. Comparisons to Quantum Molecular Dynamics (QMD) and Boltzmann-Uehling-Uhlenbeck (BUU) models are made for different equations of state.Comment: 10 pages of text and 4 figures (all ps files in a uuencoded package)

Sequential Array Cytometry: Multi-Parameter Imaging with a Single Fluorescent Channel

Heterogeneity within the human population and within diseased tissues necessitates a personalized medicine approach to diagnostics and the treatment of diseases. Functional assays at the single-cell level can contribute to uncovering heterogeneity and ultimately assist in improved treatment decisions based on the presence of outlier cells. We aim to develop a platform for high-throughput, single-cell-based assays using well-characterized hydrodynamic cell isolation arrays which allow for precise cell and fluid handling. Here, we demonstrate the ability to extract spatial and temporal information about several intracellular components using a single fluorescent channel, eliminating the problem of overlapping fluorescence emission spectra. Integrated with imaging technologies such as wide field-of-view lens-free fluorescent imaging, fiber-optic array scanning technology, and microlens arrays, use of a single fluorescent channel will reduce the cost of reagents and optical components. Specifically, we sequentially stain hydrodynamically trapped cells with three biochemical labels all sharing the same fluorescence excitation and emission spectrum. These markers allow us to analyze the amount of DNA, and compare nucleus-to-cytoplasm ratio, as well as glycosylation of surface proteins. By imaging cells in real-time we enable measurements of temporal localization of cellular components and intracellular reaction kinetics, the latter is used as a measurement of multi-drug resistance. Demonstrating the efficacy of this single-cell analysis platform is the first step in designing and implementing more complete assays, aimed toward improving diagnosis and personalized treatments to complex diseases

Su bstrate Specificity of Mam malian Folylpolyglutamate Synthetase for 5,1 0-Dideazatetrahydrofolate Analogs

SUMMARY The metabolism of 5,1 0-dideazatetrahydrofolate (DDATH

Citizen-science for the future: Advisory case studies from around the globe

© 2019 Simoniello, Jencks, Lauro, Loftis, Weslawski, Deja, Forrest, Gossett, Jeffries, Jensen, Kobara, Nolan, Ostrowski, Pounds, Roseman, Basco, Gosselin, Reed, Wills and Wyatt. The democratization of ocean observation has the potential to add millions of observations every day. Though not a solution for all ocean monitoring needs, citizen scientists offer compelling examples showcasing their ability to augment and enhance traditional research and monitoring. Information they are providing is increasing the spatial and temporal frequency and duration of sampling, reducing time and labor costs for academic and government monitoring programs, providing hands-on STEM learning related to real-world issues and increasing public awareness and support for the scientific process. Examples provided here demonstrate the wide range of people who are already dramatically reducing gaps in our global observing network while at the same time providing unique opportunities to meaningfully engage in ocean observing and the research and conservation it supports. While there are still challenges to overcome before widespread inclusion in projects requiring scientific rigor, the growing organization of international citizen science associations is helping to reduce barriers. The case studies described support the idea that citizen scientists should be part of an effective global strategy for a sustained, multidisciplinary and integrated observing system