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Carbonyl sulfide and carbon disulfide: Large-scale distributions over the western Pacific and emissions from Asia during TRACE-P
An extensive set of carbonyl sulfide (OCS) and carbon disulfide (CS2) observations were made as part of the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) project, which took place in the early spring 2001. TRACE-P sampling focused on the western Pacific region but in total included the geographic region 110°E to 290°E longitude, 5°N to 50°N latitude, and 0–12 km altitude. Substantial OCS and CS2 enhancements were observed for a great many air masses of Chinese and Japanese origin during TRACE-P. Over the western Pacific, mean mixing ratios of long-lived OCS and shorter-lived CS2 showed a gradual decrease by about 10% and a factor of 5–10, respectively, from the surface to 8–10 km altitude, presumably because land-based sources dominated their distribution during February through April 2001. The highest mean OCS and CS2levels (580 and 20 pptv, respectively, based on 2.5° × 2.5° latitude bins) were observed below 2 km near the coast of Asia, at latitudes between 25°N and 35°N, where urban Asian outflow was strongest. Ratios of OCS versus CO for continental SE Asia were much lower compared to Chinese and Japanese signatures and were strongly associated with biomass burning/biofuel emissions. We present a new inventory of anthropogenic Asian emissions (including biomass burning) for OCS and CS2 and compare it to emission estimates based on regional relationships of OCS and CS2 to CO and CO2. The OCS and CS2 results for the two methods compare well for continental SE Asia and Japan plus Korea and also for Chinese CS2 emissions. However, it appears that the inventory underestimates Chinese emissions of OCS by about 30–100%. This difference may be related to the fact that we did not include natural sources such as wetland emissions in our inventory, although the contributions from such sources are believed to be at a seasonal low during the study period. Uncertainties in OCS emissions from Chinese coal burning, which are poorly characterized, likely contribute to the discrepancy
Method for Flavor Tagging in Neutral B Meson Decays
A method is proposed for tagging the flavor of neutral mesons in the
study of CP-violating decay asymmetries. The method makes use of a possible
difference in interactions in or systems with isospins 1/2
and 3/2, and would be particularly clean if the systems can be
detected as ``'' resonances.Comment: Submitted to Phys. Rev. D. 11 pages, LaTeX, Technion-PH-92-40 / PITHA
92/39 / EFI 92-5
Metabolomics and lipidomics reveal perturbation of sphingolipid metabolism by a novel anti-trypanosomal 3-(oxazolo[4,5-b]pyridine-2-yl)anilide
Introduction: Trypanosoma brucei is the causative agent of human African trypanosomiasis, which is responsible for thousands of deaths every year. Current therapies are limited and there is an urgent need to develop new drugs. The anti-trypanosomal compound, 3-(oxazolo[4,5-b]pyridine-2-yl)anilide (OXPA), was initially identified in a phenotypic screen and subsequently optimized by structure–activity directed medicinal chemistry. It has been shown to be non-toxic and to be active against a number of trypanosomatid parasites. However, nothing is known about its mechanism of action.
Objective: Here, we have utilized an untargeted metabolomics approach to investigate the biochemical effects and potential mode of action of this compound in T. brucei.
Methods: Total metabolite extracts were analysed by HILIC-chromatography coupled to high resolution mass spectrometry.
Results: Significant accumulation of ceramides was observed in OXPA-treated T. brucei. To further understand drug-induced changes in lipid metabolism, a lipidomics method was developed which enables the measurement of hundreds of lipids with high throughput and precision. The application of this LC–MS based approach to cultured bloodstream-form T. brucei putatively identified over 500 lipids in the parasite including glycerophospholipids, sphingolipids and fatty acyls, and confirmed the OXPA-induced accumulation of ceramides. Labelling with BODIPY-ceramide further confirmed the ceramide accumulation following drug treatment.
Conclusion: These findings clearly demonstrate perturbation of ceramide metabolism by OXPA and indicate that the sphingolipid pathway is a promising drug target in T. brucei.No Full Tex
Identification of Neutral B Mesons Using Correlated Hadrons
The identification of the flavor of a neutral meson can make use of
hadrons produced nearby in phase space. Examples include the decay of
``'' resonances or the production of hadrons as a result of the
fragmentation process. Some aspects of this method are discussed, including
time-dependent effects in neutral decays to flavor states, to eigenstates
of CP and to other states, and the effects of possible coherence between
and in the initial state. We study the behavior of the leading
hadrons in -quark jets and the expected properties of resonances.
These are extrapolated from the corresponding resonances, of whose
properties we suggest further studies.Comment: To be submitted to Phys. Rev. D. 26 pages, LaTeX, figures not
included (available upon request). Technion-PH-93-32 / EFI 93-4
Detection of intrinsic source structure at ~3 Schwarzschild radii with Millimeter-VLBI observations of SAGITTARIUS A*
We report results from very long baseline interferometric (VLBI) observations
of the supermassive black hole in the Galactic center, Sgr A*, at 1.3 mm (230
GHz). The observations were performed in 2013 March using six VLBI stations in
Hawaii, California, Arizona, and Chile. Compared to earlier observations, the
addition of the APEX telescope in Chile almost doubles the longest baseline
length in the array, provides additional {\it uv} coverage in the N-S
direction, and leads to a spatial resolution of 30 as (3
Schwarzschild radii) for Sgr A*. The source is detected even at the longest
baselines with visibility amplitudes of 4-13% of the total flux density.
We argue that such flux densities cannot result from interstellar refractive
scattering alone, but indicate the presence of compact intrinsic source
structure on scales of 3 Schwarzschild radii. The measured nonzero
closure phases rule out point-symmetric emission. We discuss our results in the
context of simple geometric models that capture the basic characteristics and
brightness distributions of disk- and jet-dominated models and show that both
can reproduce the observed data. Common to these models are the brightness
asymmetry, the orientation, and characteristic sizes, which are comparable to
the expected size of the black hole shadow. Future 1.3 mm VLBI observations
with an expanded array and better sensitivity will allow a more detailed
imaging of the horizon-scale structure and bear the potential for a deep
insight into the physical processes at the black hole boundary.Comment: 11 pages, 5 figures, accepted to Ap
Molecular tools for bathing water assessment in Europe:Balancing social science research with a rapidly developing environmental science evidence-base
The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science-policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2Â h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96Â h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations
It's time to address fear of cancer recurrence in family caregivers: usability study of an virtual version of the Family Caregiver—Fear Of Recurrence Therapy (FC-FORT)
BackgroundFamily caregivers of cancer survivors experience equal or greater levels of fear of cancer recurrence (FCR) than survivors themselves. Some interventions have demonstrated their ability to reduce FCR among cancer survivors and dyads (patient and caregivers). However, to date, no validated intervention exists to focus solely on family caregiver's FCR.ObjectivesThis study aimed to (1) adapt the evidence-based in-person Fear Of Recurrence Therapy (FORT) for family caregivers (referred here in as FC-FORT) and to a virtual delivery format and (2) test its usability when offered virtually.MethodsThe adaptation of FC-FORT was overseen by an advisory board and guided by the Information Systems Research Framework. Following this adaptation, female family caregivers and therapists were recruited for the usability study. Participants took part in 7 weekly virtual group therapy sessions, a semi-structured exit interview and completed session feedback questionnaires. Therapists were offered a virtual training and weekly supervision. Fidelity of treatment administration was assessed each session. Quantitative data were analyzed using descriptive statistics. Exit interviews were transcribed verbatim using NVivo Transcription and coded using conventional content analysis. Results were presented back to the advisory board to further refine FC-FORT.ResultsThe advisory board (n = 16) met virtually on 7 occasions to adapt FC-FORT (i.e., patient manuals, virtual format) and discuss recruitment strategies. Minor (e.g., revised text, adapted materials to virtual format) and major adaptations (e.g., added and rearranged sessions) were made to FC-FORT and subsequently approved by the advisory board. Four family caregivers and three therapists took part in the first round of the usability testing. Six family caregivers and the same three therapists took part in the second round. Overall, participants were very satisfied with FC-FORT's usability. Qualitative analysis identified 4 key themes: usability of FC-FORT, satisfaction and engagement with content, group cohesion, and impact of FC-FORT. All participants indicated that they would recommend FC-FORT to others as is.ConclusionsUsing a multidisciplinary advisory board, our team successfully adapted FC-FORT and tested its usability using videoconferencing. Results from this study indicate that the efficacy and acceptability of FC-FORT are now ready to be tested in a larger pilot study
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