5,013 research outputs found
Using GES DISC Data to Study Kilauea Volcano of 2018
Kilauea volcano in Hawaii which erupted in early May 2018 injected massive amount of SO2 and ash into the atmosphere. The lava flow during the eruption destroyed many home and neighborhoods. The SO2 plume during the eruption of Kilauea volcano is analyzed from May to August 2018 using multiple satellite products such as Level 2 TROPspheric Monitoring Instrument (TROPOMI) and Level 3 Ozone Monitoring Instrument (OMI) from the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC). GES DISC hosts multi-disciplinary Earth science data sets that can be used to analyze natural disasters, such as the Kilauea volcano. Additionally, GES DISC's Giovanni tool can be used to visualize these data. We acquired OMI through the subsetting function, which is processed by the GES DISC in-house developed backend software Level3/4 Regrider and Subsetter (L34RS) and TROPOMI using OPeNDAP.Data from the OMI OMSO2e product showed elevated levels of SO2 amounts during the eruption between May to August 2018. Similarly, ground-based stations at Hawaii Volcanoes National Park recorded higher SO2 concentrations during the same time period. This study uses wind direction from Modern-Era Retrospective analysis for Research and Applications, version 2 (MERRA-2) to analyze the transport and dispersion of SO2 plume and map lava flows from the volcano using thermal images from Visible Infrared Imaging Radiometer Suite (VIIRS). Furthermore, satellite observations combined with socioeconomic and public health data are used to analyze its impact in public health
Primary enucleation for group D retinoblastoma in the era of systemic and targeted chemotherapy: the price of retaining an eye
BACKGROUND: Chemotherapy is increasingly used as primary treatment for group D retinoblastoma, whereas primary enucleation is considered to have a diminishing role. This study aimed to compare the management course, including number of examinations under anaesthesia (EUAs), of group D patients treated by enucleation versus chemotherapy. METHODS: A retrospective analysis of 92 group D patients, of which 40 (37 unilateral) underwent primary enucleation and 52 (17 unilateral) were treated with intravenous chemotherapy. Number of EUAs was compared between the treatment groups with respect to the whole cohort, using univariate and multivariate analysis, and to unilateral cases only. RESULTS: Patients were followed up for a median of 61 months (mean: 66, range: 14-156), in which time primary enucleated patients had on average seven EUAs and chemotherapy-treated patients 21 EUAs (p<0.001). Chemotherapy, young age, bilateral disease, multifocal tumours, familial and germline retinoblastoma were found on univariate analysis to correlate with increased number of EUAs (p≤0.019). On multivariate analysis, however, only treatment type and presentation age were found significant (p≤0.001). On subanalysis of the unilateral cases, patients undergoing primary enucleation had in average seven EUAs, as compared with 16 in the chemotherapy group (p<0.001). Of the 55 unilateral-presenting patients, a new tumour developed in the fellow eye only in a single familial case. CONCLUSION: Group D patients' families should be counselled regarding the significant difference in number of EUAs following primary enucleation versus chemotherapy when deciding on a treatment strategy. In this regard, primary enucleation would be most beneficial for older patients with unilateral disease
Chlorination Disinfection By-products and Pancreatic Cancer Risk
Chlorination disinfection by-products (CDBPs) are produced during the treatment of water with chlorine to remove bacterial contamination. CDBPs have been associated with an increased risk of bladder cancer. There is also some evidence that they may increase the risk of pancreatic cancer. We report results from a population-based case–control study of 486 incident cases of pancreatic cancer and 3,596 age- and sex-matched controls. Exposure to chlorination by-products was estimated by linking lifetime residential histories to two different databases containing information on CDBP levels in municipal water supplies. Logistic regression analysis found no evidence of increased pancreatic cancer risk at higher CDBP concentrations (all odds ratios < 1.3). Null findings were also obtained assuming a latency period for pancreatic cancer induction of 3, 8, or 13 years
Aerosol and splatter generation with rotary handpieces used in restorative and orthodontic dentistry:a systematic review
Abstract: Introduction: The COVID-19 pandemic has caused major disruptions in dental care globally, in part due to the potential for contaminated aerosol to be generated by dental activities. This systematic review assesses the literature for changes in aerosol-contamination levels when rotary instruments are used, (1) as distance increases from patient’s mouth; (2) as time passes after the procedure; and (3) when using different types of handpieces. Methods: The review methods and reporting are in line with PRISMA statements. A structured search was conducted over five platforms (September 2021). Studies were assessed independently by two reviewers. To be eligible studies had to assess changes in levels of aerosol contamination over different distances, and time points, with rotary hand instruments. Studies’ methodologies and the sensitivity of the contamination-measurement approaches were evaluated. Results are presented descriptively. Results: From 422 papers identified, 23 studies were eligible. All investigated restorative procedures using rotary instruments and one study additionally looked at orthodontic bracket adhesive material removal. The results suggest contamination is significantly reduced over time and distance. However, for almost all studies that investigated these two factors, the sizes of the contaminated particles were not considered, and there were inconclusive findings regarding whether electric-driven handpieces generate lower levels of contaminated particles. Conclusion: Aerosol contamination levels reduce as distances, and post-procedure times increase. However, there was sparce and inconsistent evidence on the clearing time and no conclusions could be drawn. High-speed handpieces produce significantly higher levels of contamination than slow-speed ones, and to a lesser extent, micro-motor handpieces. However, when micro-motor handpieces were used with water, the contamination levels rose and were similar to high-speed handpiece contamination levels
Phenotypic relationships between docility and reproduction in Angus heifers
Citation: White, K. L., Bormann, J. M., Olson, K. C., Jaeger, J. R., Johnson, S., Downey, B., . . . Weaber, R. L. (2016). Phenotypic relationships between docility and reproduction in Angus heifers. Journal of Animal Science, 94(2), 483-489. doi:10.2527/jas2015-9327The objective of this study was to elucidate the phenotypic relationships between docility and first-service AI conception rate in heifers. Data (n = 337) collected from 3 cooperator herds in Kansas at the start of synchronization protocol included exit velocity (EV), chute score (CS), fecal cortisol (FC), and blood serum cortisol (BC). Data were analyzed using logistic regression with 30-d pregnancy rate as the dependent variable. The model included the fixed effect of contemporary group and the covariates FC, BC, EV, CS, BW, and age. Correlation coefficients were calculated between all continuous traits. Pregnancy rate ranged from 34% to 60% between herds. Blood cortisol positively correlated with EV (r = 0.22, P < 0.01), negatively correlated with age (r = -0.12, P < 0.03), and tended to be negatively correlated with BW (r = -0.10, P = 0.09). Exit velocity was positively correlated with CS (r = 0.24, P < 0.01) and negatively correlated with BW (r = -0.15, P < 0.01) and age (r = -0.12, P < 0.03). Chute score negatively correlated with age (r = -0.14, P < 0.01), and age and BW were moderately positively correlated (r = 0.42, P < 0.01), as expected. Older, heavier animals generally had better temperament, as indicated by lower BC, EV, and CS. The power of our test could detect no significant predictors of 30-d pregnancy for the combined data from all ranches. When the data were divided by ranch, CS (P < 0.03) and BW (P < 0.01) were both significant predictors for 30-d pregnancy for ranch 1. The odds ratio estimate for CS has an inverse relationship with pregnancy, meaning that a 1-unit increase in average CS will reduce the probability of pregnancy at ranch 1 by 48.1%. Weight also has a negative impact on pregnancy because a 1-kg increase in BW will decrease the probability of pregnancy by 2.2%. Fertility is a complex trait that depends on many factors; our data suggest that docility is 1 factor that warrants further investigation
Universal quantum control of two-electron spin quantum bits using dynamic nuclear polarization
One fundamental requirement for quantum computation is to perform universal
manipulations of quantum bits at rates much faster than the qubit's rate of
decoherence. Recently, fast gate operations have been demonstrated in logical
spin qubits composed of two electron spins where the rapid exchange of the two
electrons permits electrically controllable rotations around one axis of the
qubit. However, universal control of the qubit requires arbitrary rotations
around at least two axes. Here we show that by subjecting each electron spin to
a magnetic field of different magnitude we achieve full quantum control of the
two-electron logical spin qubit with nanosecond operation times. Using a single
device, a magnetic field gradient of several hundred milliTesla is generated
and sustained using dynamic nuclear polarization of the underlying Ga and As
nuclei. Universal control of the two-electron qubit is then demonstrated using
quantum state tomography. The presented technique provides the basis for single
and potentially multiple qubit operations with gate times that approach the
threshold required for quantum error correction.Comment: 11 pages, 4 figures. Supplementary Material included as ancillary
fil
A Synthesis of Global Urbanization Projections
This chapter reviews recent literature on global projections of future urbanization, covering the population, economic and physical extent perspectives. We report on several recent findings based on studies and reports on global patterns of urbanization. Specifically, we review new literature that makes projections about the spatial pattern, rate, and magnitude of urbanization change in the next 30–50 years. While projections should be viewed and utilized with caution, the chapter synthesis reports on several major findings that will have significant socioeconomic and environmental impacts including the following: By 2030, world urban population is expected to increase from the current 3.4 billion to almost 5 billion; Urban areas dominate the global economy – urban economies currently generate more than 90 % of global Gross Value Added; From 2000 to 2030, the percent increase in global urban land cover will be over 200 % whereas the global urban population will only grow by a little over 70 %. Our synthesis of recent projections suggest that between 50%–60% of the total urban land in existence in 2030 will be built in the first three decades of the 21st century.
Challenges and limitations of urban dynamic projections are discussed, as well as possible innovative applications and potential pathways towards sustainable urban futures
Coupling molecular spin states by photon-assisted tunneling
Artificial molecules containing just one or two electrons provide a powerful
platform for studies of orbital and spin quantum dynamics in nanoscale devices.
A well-known example of these dynamics is tunneling of electrons between two
coupled quantum dots triggered by microwave irradiation. So far, these
tunneling processes have been treated as electric dipole-allowed
spin-conserving events. Here we report that microwaves can also excite
tunneling transitions between states with different spin. In this work, the
dominant mechanism responsible for violation of spin conservation is the
spin-orbit interaction. These transitions make it possible to perform detailed
microwave spectroscopy of the molecular spin states of an artificial hydrogen
molecule and open up the possibility of realizing full quantum control of a two
spin system via microwave excitation.Comment: 13 pages, 9 figure
- …