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Drivers and fleets are increasingly turning to the hundreds of light-duty, alternative fuel, and advanced technology vehicle models that reduce petroleum use, save on fuel costs, and cut emissions. This guide provides a comprehensive list of the 2015 light-duty models that use alternative fuels or advanced fuel-saving technologies.
This annual report of the Alternative Fuel Transportation Program, which ensures compliance with DOE regulations covering state government and alternative fuel provider fleets pursuant to the Energy Policy Act of 1992 (EPAct), as amended, provides fleet compliance results for manufacturing year 2014 / fiscal year 2015.
The 2015 Renewable Energy Data Book provides facts and figures on energy and electricity use, renewable electricity in the United States, global renewable energy development, wind power, solar power, geothermal power, biopower, hydropower, marine and hydrokinetic power, hydrogen, renewable fuels, and clean energy investment.
Soon after the onset of an eruption, model forecasts of ash dispersal are used to mitigate the hazards to aircraft, infrastructure, and communities downwind. However, it is a significant challenge to constrain the model inputs during an evolving eruption. Here we demonstrate that volcanic lightning may be used in tandem with satellite detection to recognize and quantify changes in eruption style and intensity. Using the eruption of Calbuco volcano in southern Chile on 22 and 23 April 2015, we investigate rates of umbrella cloud expansion from satellite observations, occurrence of lightning, and mapped characteristics of the fall deposits. Our remote sensing analysis gives a total erupted volume that is within uncertainty of the mapped volume (0.56 ± 0.28 km3 bulk). Furthermore, observations and volcanic plume modeling further suggest that electrical activity was enhanced both by ice formation in the ash clouds >10 km above sea level and development of a low-level charge layer from ground-hugging currents.
Various physical processes are known to cause acceleration, loss, and transport of energetic electrons in the Earth's radiation belts, but their quantitative roles in different time and space need further investigation. During the largest storm over the past decade (17 March 2015), relativistic electrons experienced fairly rapid acceleration up to ~7 MeV within 2 days after an initial substantial dropout, as observed by Van Allen Probes. In the present paper, we evaluate the relative roles of various physical processes during the recovery phase of this large storm using a 3-D diffusion simulation. By quantitatively comparing the observed and simulated electron evolution, we found that chorus plays a critical role in accelerating electrons up to several MeV near the developing peak location and produces characteristic flat-top pitch angle distributions. By only including radial diffusion, the simulation underestimates the observed electron acceleration, while radial diffusion plays an important role in redistributing electrons and potentially accelerates them to even higher energies. Moreover, plasmaspheric hiss is found to provide efficient pitch angle scattering losses for hundreds of keV electrons, while its scattering effect on > 1 MeV electrons is relatively slow. Although an additional loss process is required to fully explain the overestimated electron fluxes at multi-MeV, the combined physical processes of radial diffusion and pitch angle and energy diffusion by chorus and hiss reproduce the observed electron dynamics remarkably well, suggesting that quasi-linear diffusion theory is reasonable to evaluate radiation belt electron dynamics during this big storm.
Trapped electrons in Earth's outer Van Allen radiation belt are influenced profoundly by solar phenomena such as high-speed solar wind streams, coronal mass ejections (CME), and interplanetary (IP) shocks. In particular, strong IP shocks compress the magnetosphere suddenly and result in rapid energization of electrons within minutes. It is believed that the electric fields induced by the rapid change in the geomagnetic field are responsible for the energization. During the latter part of March 2015, a CME impact led to the most powerful geomagnetic storm (minimum Dst = -223 nT at 17 March, 23 UT) observed not only during the Van Allen Probe era but also the entire preceding decade. Magnetospheric response in the outer radiation belt eventually resulted in elevated levels of energized electrons. The CME itself was preceded by a strong IP shock whose immediate effects vis-a-vis electron energization were observed by sensors on board the Van Allen Probes. The comprehensive and high-quality data from the Van Allen Probes enable the determination of the location of the electron injection, timescales, and spectral aspects of the energized electrons. The observations clearly show that ultrarelativistic electrons with energies E > 6 MeV were injected deep into the magnetosphere at L ≈ 3 within about 2 min of the shock impact. However, electrons in the energy range of ≈250 keV to ≈900 keV showed no immediate response to the IP shock. Finally, electric and magnetic fields resulting from the shock-driven compression complete the comprehensive set of observations that provide a full description of the near-instantaneous electron energization.
Abstract Sea breezes penetrate inland more than 100 km. Using 7 years of meteorological observations, we have identified 470 cases of deep inland (>100 km) penetrating sea breezes at the Savannah River Site between March and October (27% of days) of 2015–2021. We compared measurements of temperature, dewpoint temperature, incoming solar radiation, cloud fraction, and lightning on days of sea breeze initiation, the day after the sea breeze passage, and all other nonsea breeze (NSB) days for these 8 months over the 7 years. Days of sea breeze initiation were found to have lower cloud fraction, higher temperature, and greater incoming solar radiation compared with NSB days. Variations occurred by time of year as days after the sea breeze passage were found to have higher dewpoint temperature than NSB days in the spring. Lightning density measurements indicated that residual sea breeze conditions could drive earlier initiation of deep convection on days following the sea breeze than normal non sea breeze days. This data set provides a 7‐year record of sea breezes which can be leveraged for future studies.
Oxygen inventory of the global ocean has declined in recent decades potentially due to the warming-induced reduction in solubility as well as the circulation and biogeochemical changes associated with ocean warming and increasing stratification. Earth System Models predict continued oxygen decline for this century with profound impacts on marine ecosystem and fisheries. Observational constraint on the rate of oxygen loss is crucial for assessing the ability of models to accurately simulate these changes. There are only a few observational assessments of the global oceanic oxygen inventory reporting a range of oxygen loss. This study develops a gridded data set of dissolved oxygen for the global oceans using optimal interpolation method. The resulting gridded product includes full-depth map of dissolved oxygen as 5-year moving average from 1965 to 2015 with uncertainty estimates. The uncertainty can come from unresolved small-scale and high-frequency variability and mapping errors. The multi-decadal trend of global dissolved oxygen is in the range of -281 to -373 Tmol/decade. This estimate is more conservative than previous works. In this study, the grid points far from the observations are essentially set equal to zero anomaly from the climatology. Calculating global inventory with this approach produces a relatively conservative estimate; thus, the results from this study likely provide a useful lower bound estimate of the global oxygen loss.
This letter concerns an article recently published in Current Opinion in Biotechnology by Baroukh et al. entitled "Mathematical modeling of unicellular microalgae and cyanobacteria metabolism for biofuel production" (2015 Mar 26; 33:198-205). The issue we wish to bring to light is the authors’ claim that dynamic metabolic models including Hybrid Cybernetic Model (HCM) (Kim et al., 2008; Song et al., 2009) and Lumped HCM (L-HCM) (Song and Ramkrishna, 2010; 2011) are based on the balanced growth hypothesis so that they are unable to simulate the accumulation of intracellular metabolites. This is a misrepresentation of these models due to the following reasons.
Exposure to high levels of road traffic noise at the most exposed building facade is increasing, both due to urbanization and due to overall traffic increase. This study investigated how different noise reduction measures would influence the noise exposure on a city-wide scale in Gothenburg, a city in Sweden with approximately 550,000 inhabitants. Noise exposure was estimated under several different scenarios for the period 2015–2035, using the standardized Nordic noise prediction method together with traffic flow measurements and population statistics. The scenarios were based on reducing speed limits, reducing traffic flows, introducing more electrically powered vehicles and introducing low-noise tires and pavements. The most effective measures were introducing low-noise tires or pavements, which in comparison to business as usual produced between 13% and 29% reduction in the number of inhabitants exposed above 55 dB equivalent level.
Highlights: • Lack of data on maternal exposure to toxic and trace elements in Africa. • Longitudinal blood measurements of Pb, Cd, Zn, Cu and Mn during pregnancy in Benin. • Evidence of maternal exposure to Pb and Cd. • Identification of potential sources for Pb exposure during pregnancy. During pregnancy, fetal development can be hindered by maternal exposure to toxic elements and abnormal concentrations of trace elements. Few data are available in African countries. Our goal was to assess the body burden of lead (Pb), cadmium (Cd), manganese (Mn), zinc (Zn) and copper (Cu) in pregnant women in Benin. The study was carried out in Sô-Ava district, from November 2015 to April 2016. Sixty women were recruited from the RECIPAL pre-conceptional cohort study. In all women, blood samples were collected during the first trimester of pregnancy. Thirty-two women had additional maternal and cord blood samples collected at delivery. Blood samples were analyzed by inductively coupled plasma mass spectrometry. At delivery, Cd median (IQR) concentration in maternal blood was 0.34 µg/L (0.24–0.46) in this non-smoking population. Pb median (IQR) concentration in maternal blood at delivery was 37.4 µg/L (30.5–52.0), with 31.3% of blood Pb levels above the 50 μg/L threshold. These pregnant women lived in semi-rural lakeside villages. Potential sources of Pb exposure identified during pregnancy were having water supply by drill pump and activities such as smoking fish by the woman and fishing by the household head. At delivery, Zn, Cu, and Mn median (IQR) concentrations in maternal blood were, respectively, 5415 μg/L (4894–5822), 1609 μg/L (1295–1771) and 16.0 μg/L (12.5–20.8). Pb, Cd, Mn and Cu blood concentrations were significantly higher at delivery than during the first trimester of pregnancy. Pb, Cd, Zn and Cu concentrations were significantly lower in cord blood than in maternal blood, contrary to Mn concentration, which was significantly higher in cord blood than in maternal blood at delivery. This exploratory study is the first one performed in Benin, and warns us about exposition of women from Sô-Ava district to Pb and Cd during pregnancy.
After four years of sometimes contentious negotiations (that at one point required a two-year extension from the U.S. Congress), the United States and Republic of Korea signed a new nuclear cooperation agreement in the summer of 2015. These negotiations caused strain in one of the closest bilateral relationships the U.S. has in Asia – a regional priority for the foreign policy of the Obama administration. This paper examines energy conflict within the confines of an otherwise cooperative and productive partnership. It examines the strategic, technical, economic, and political factors that extended the negotiation period and the creative compromises that led to a final agreement. It then considers the potential pit-falls in implementing the agreement and the implications, in terms of process and substance, for future negotiations regarding civilian nuclear cooperation.
Purpose: Radiation oncology relies on rapidly evolving technology and highly complex processes. The US Food and Drug Administration collects reports of adverse events related to medical devices. We sought to characterize all events involving radiation oncology devices (RODs) from the US Food and Drug Administration's postmarket surveillance Manufacturer and User Facility Device Experience (MAUDE) database, comparing these with non–radiation oncology devices. Methods and Materials: MAUDE data on RODs from 1991 to 2015 were sorted into 4 product categories (external beam, brachytherapy, planning systems, and simulation systems) and 5 device problem categories (software, mechanical, electrical, user error, and dose delivery impact). Outcomes included whether the device was evaluated by the manufacturer, adverse event type, remedial action, problem code, device age, and time since 510(k) approval. Descriptive statistics were performed with linear regression of time-series data. Results for RODs were compared with those for other devices by the Pearson χ{sup 2} test for categorical data and 2-sample Kolmogorov-Smirnov test for distributions. Results: There were 4234 ROD and 4,985,698 other device adverse event reports. Adverse event reports increased over time, and events involving RODs peaked in 2011. Most ROD reports involved external beam therapy (50.8%), followed by brachytherapy (24.9%) and treatment planning systems (21.6%). The top problem types were software (30.4%), mechanical (20.9%), and user error (20.4%). RODs differed significantly from other devices in each outcome (P<.001). RODs were more likely to be evaluated by the manufacturer after an event (46.9% vs 33.0%) but less likely to be recalled (10.5% vs 37.9%) (P<.001). Device age and time since 510(k) approval were shorter among RODs (P<.001). Conclusions: Compared with other devices, RODs may experience adverse events sooner after manufacture and market approval. Close postmarket surveillance, improved software design, and manufacturer–user training may help mitigate these events.
Purpose: To quantify and determine the relationship between oncology departmental/division heads and private industry vis-à-vis potential financial conflict of interests (FCOIs) as publicly reported by the Centers for Medicare and Medicaid Services Open Payments database. Methods and Materials: We extracted the names of the chairs/chiefs in medical oncology (MO) and chairs of radiation oncology (RO) for 81 different institutions with both RO and MO training programs as reported by the Association of American Medical Colleges. For each leader, the amount of consulting fees and research payments received in 2015 was determined. Logistic modeling was used to assess associations between the 2 endpoints of receiving a consulting fee and receiving a research payment with various institution-specific and practitioner-specific variables included as covariates: specialty, sex, National Cancer Institute designation, PhD status, and geographic region. Results: The majority of leaders in MO were reported to have received consulting fees or research payments (69.5%) compared with a minority of RO chairs (27.2%). Among those receiving payments, the average (range) consulting fee was $13,413 ($200-$70,423) for MO leaders and $6463 ($837-$16,205) for RO chairs; the average research payment for MO leaders receiving payments was $240,446 ($156-$1,234,762) and $295,089 ($160-$1,219,564) for RO chairs. On multivariable regression when the endpoint was receipt of a research payment, those receiving a consulting fee (odds ratio [OR]: 5.34; 95% confidence interval [CI]: 2.22-13.65) and MO leaders (OR: 5.54; 95% CI: 2.62-12.18) were more likely to receive research payments. Examination of the receipt of consulting fees as the endpoint showed that those receiving a research payment (OR: 5.41; 95% CI: 2.23-13.99) and MO leaders (OR: 3.06; 95% CI: 1.21-8.13) were more likely to receive a consulting fee. Conclusion: Leaders in academic oncology receive consulting or research payments from industry. Relationships between oncology leaders and industry can be beneficial, but guidance is needed to develop consistent institutional policies to manage FCOIs.
Multiple efforts have been made in recent years to establish national benchmarks for research productivity among US radiation oncology residents. Morgan et al found a mean of 1.01 first-author, PubMed-searchable articles published by US radiation oncology residents over 4 years of residency between 2002 and 2007, whereas Verma et al found a mean of 1.97 first-author, PubMed-searchable articles published by members of the graduating US radiation oncology residency classes of 2014 and 2015. In this study, we sought to establish new national benchmarks for US radiation oncology resident research productivity and characterize the scholarly work produced by graduating US radiation oncology residents.
Rupture in the 2015 M7.8 Gorkha earthquake nucleated at the downdip edge of the Main Himalayan Thrust (MHT) near the transition from interseismic locking to aseismic creep beneath the Tibetan plateau, and propagated incompletely towards the Main Frontal Thrusts (MFT). Despite the imposition of a substantial static strain in the mid-décollement, afterslip on the MHT within a year of the earthquake had decayed to negligible levels. Earthquakes that incompletely rupture the MHT (7 < Mw < 7.9) have been relatively common in the past two centuries, and as a consequence heterogeneous patches of stored elastic strain must exist throughout the Himalaya similar to that emplaced by the Gorkha earthquake. We show that these patches of stored strain are not dissipated by creep or by subsequent updip earthquakes, with the possible exceptions of a sequence of moderate earthquakes to the west of the great 1950 Assam earthquake, and to the east of the Kangra 1905 earthquake. It is thus considered likely that mid-décollement strain newly imposed by the Gorkha earthquake, and other recent incomplete ruptures will be incorporated in the rupture of a future much larger earthquake. Incomplete ruptures (i.e. those that nucleate downdip but fail to rupture the frontal thrusts) appear to occur preferentially in parts of the central Himalaya characterized by relatively narrow transition regions of interseismic decoupling (<30 km downdip). Assuming uniform strain at failure these narrow zones are unable to store large amounts of strain energy compared to wide zones of interseismic decoupling. Since the transition from fully locked to a fully creeping rheology depends partly on temperature, to first order the width of the interseismic decoupling transition zone depends on the local dip of the MHT. Where the decoupling zone is narrow (25 km) moderate earthquakes (6 < Mw < 7) are observed to occur at intervals of a few hundred years. Where the transition zone is wide (e.g. Kashmir and Assam, 150 km) great earthquakes nucleate at long time intervals (millennia). Because the cumulative moment release of moderate earthquakes in regions of narrow seismic decoupling is insufficient to keep up with plate convergence, we conclude that megaquakes that eventually sweep through these regions are augmented by the heterogenous fossil strain of former incomplete ruptures. Because great earthquakes in the central Himalaya are inferred to nucleate from moderate earthquakes near the base of the MHT, the preparation zones of these moderate earthquakes may provide opportunities for forecasting the approach of future great earthquakes.
The collection and evaluation of family health history in a clinical setting presents an opportunity to discuss cancer risk, tailor cancer screening recommendations, and identify people with an increased risk of carrying a pathogenic variant who may benefit from referral to genetic counseling and testing. National recommendations for breast and colorectal cancer screening indicate that men and women who have a first-degree relative affected with these types of cancers may benefit from talking to a healthcare provider about starting screening at an earlier age and other options for cancer prevention. The prevalence of reporting a first-degree relative who had cancer was assessed among adult respondents of the 2015 National Health Interview Survey who had never had cancer themselves (n = 27,999). We found 35.6% of adults reported having at least one first-degree relative with cancer at any site. Significant differences in reporting a family history of cancer were observed by sex, age, race/ethnicity, educational attainment, and census region. Nearly 5% of women under age 50 and 2.5% of adults under age 50 had at least one first-degree relative with breast cancer or colorectal cancer, respectively. We estimated that 5.8% of women had a family history of breast or ovarian cancer that may indicate increased genetic risk. A third of U.S. adults who have never had cancer report a family history of cancer in a first-degree relative. Furthermore, this finding underscores the importance of using family history to inform discussions about cancer risk and screening options between healthcare providers and their patients.
The 30 May 2015 Mw 7.9 Bonin earthquake, one of the largest and deepest earthquakes ever recorded by modern seismology, provides a unique opportunity to study the source process and physical mechanisms of deep-focus earthquakes. We develop a novel back-projection technique that allows source imaging in full three-dimensional space with high depth resolution. Our results indicate an initial SW-NE bilateral source propagation followed by a northwest source extension. The multiple-source inversion reveals a two-step source process with propagating directions near-perpendicular to each other, consistent with the 3D back-projection result. The spatial distribution and focal mechanisms of the sub-events cannot be modeled by a single planar rupture, which may display a curved rupture plane or sub-events crossing multiple fault interfaces. Thus, the complex source process can be best explained by stress or structure heterogeneity within the deep slab.