| 1. |
- Aad, G, et al.
(författare)
-
- 2015
-
swepub:Mat__t
|
|
| 2. |
- Fenstermacher, M.E., et al.
(författare)
-
DIII-D research advancing the physics basis for optimizing the tokamak approach to fusion energy
- 2022
-
Ingår i: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 62:4
-
Tidskriftsartikel (refereegranskat)abstract
- DIII-D physics research addresses critical challenges for the operation of ITER and the next generation of fusion energy devices. This is done through a focus on innovations to provide solutions for high performance long pulse operation, coupled with fundamental plasma physics understanding and model validation, to drive scenario development by integrating high performance core and boundary plasmas. Substantial increases in off-axis current drive efficiency from an innovative top launch system for EC power, and in pressure broadening for Alfven eigenmode control from a co-/counter-I p steerable off-axis neutral beam, all improve the prospects for optimization of future long pulse/steady state high performance tokamak operation. Fundamental studies into the modes that drive the evolution of the pedestal pressure profile and electron vs ion heat flux validate predictive models of pedestal recovery after ELMs. Understanding the physics mechanisms of ELM control and density pumpout by 3D magnetic perturbation fields leads to confident predictions for ITER and future devices. Validated modeling of high-Z shattered pellet injection for disruption mitigation, runaway electron dissipation, and techniques for disruption prediction and avoidance including machine learning, give confidence in handling disruptivity for future devices. For the non-nuclear phase of ITER, two actuators are identified to lower the L-H threshold power in hydrogen plasmas. With this physics understanding and suite of capabilities, a high poloidal beta optimized-core scenario with an internal transport barrier that projects nearly to Q = 10 in ITER at ∼8 MA was coupled to a detached divertor, and a near super H-mode optimized-pedestal scenario with co-I p beam injection was coupled to a radiative divertor. The hybrid core scenario was achieved directly, without the need for anomalous current diffusion, using off-axis current drive actuators. Also, a controller to assess proximity to stability limits and regulate β N in the ITER baseline scenario, based on plasma response to probing 3D fields, was demonstrated. Finally, innovative tokamak operation using a negative triangularity shape showed many attractive features for future pilot plant operation.
|
|
| 3. |
|
|
| 4. |
- Lind, Lars, et al.
(författare)
-
Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)
- 2021
-
Ingår i: eLife. - : eLife Sciences Publications Ltd. - 2050-084X. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions.
|
|
| 5. |
|
|
| 6. |
- Bixby, H., et al.
(författare)
-
Rising rural body-mass index is the main driver of the global obesity epidemic in adults
- 2019
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 569:7755, s. 260-4
-
Tidskriftsartikel (refereegranskat)abstract
- Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.
|
|
| 7. |
- Barucca, G., et al.
(författare)
-
The potential of Λ and Ξ- studies with PANDA at FAIR
- 2021
-
Ingår i: European Physical Journal A. - : Springer Nature. - 1434-6001 .- 1434-601X. ; 57:4
-
Tidskriftsartikel (refereegranskat)abstract
- The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: p¯ p→ Λ¯ Λ and p¯ p→ Ξ¯ +Ξ-. The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA.
|
|
| 8. |
- Mishra, A, et al.
(författare)
-
Diminishing benefits of urban living for children and adolescents' growth and development
- 2023
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 615:7954, s. 874-883
-
Tidskriftsartikel (refereegranskat)abstract
- Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.
|
|
| 9. |
|
|
| 10. |
|
|
| 11. |
|
|
| 12. |
|
|
| 13. |
- Andreoni, I., et al.
(författare)
-
Follow Up of GW170817 and Its Electromagnetic Counterpart by Australian-Led Observing Programmes
- 2017
-
Ingår i: Publications Astronomical Society of Australia. - : Cambridge University Press (CUP). - 1323-3580 .- 1448-6083. ; 34
-
Forskningsöversikt (refereegranskat)abstract
- The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (similar to 2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
|
|
| 14. |
|
|
| 15. |
- Yao, S. T., et al.
(författare)
-
Waves in Kinetic-Scale Magnetic Dips : MMS Observations in the Magnetosheath
- 2019
-
Ingår i: Geophysical Research Letters. - : AMER GEOPHYSICAL UNION. - 0094-8276 .- 1944-8007. ; 46:2, s. 523-533
-
Tidskriftsartikel (refereegranskat)abstract
- Kinetic scale magnetic dips (KSMDs), with a significant depression in magnetic field strength, and scale length close to and less than one proton gyroradius, were reported in the turbulent plasmas both in recent observation and numerical simulation studies. These KSMDs likely play important roles in energy conversion and dissipation. In this study, we present observations of the KSMDs that are labeled whistler mode waves, electrostatic solitary waves, and electron cyclotron waves in the magnetosheath. The observations suggest that electron temperature anisotropy or beams within KSMD structures provide free energy to generate these waves. In addition, the occurrence rates of the waves are higher in the center of the magnetic dips than at their edges, implying that the KSMDs might be the origin of various kinds of waves. We suggest that the KSMDs could provide favorable conditions for the generation of waves and transfer energy to the waves in turbulent magnetosheath plasmas. Plain Language Summary The Earth's magnetosheath is a turbulent plasma environment where energy conversion, particle acceleration, and mass and momentum transport take place. Many of these key processes involve kinetic-scale physics. However, in-depth studies from previous missions are limited by their lower spacecraft data resolution. The recent Magnetospheric Multiscale (MMS) mission provides us with a large amount of high-temporal cadence data for studying kinetic-scale physics in the magnetosheath. In this study, we report whistler mode waves, electrostatic solitary waves and electron cyclotron waves within kinetic-scale magnetic dips (KSMDs) that can be generated in the turbulent magnetosheath. These waves could be excited by electron temperature anisotropy or beams. As is well known, plasma waves are important processes in converting energy, accelerating and scattering electrons and ions, and modifying the distributions of charged particles. If plasma instabilities develop within the KSMDs, the resulting waves could absorb free energy from plasma particles and may propagate out of the KSMDs. Thus, our discoveries could significantly advance the understanding of energy conversion and dissipation for kinetic-scale turbulence. This study provides a new reference not only for observations in space physics but also for related basic plasma theories and numerical simulations.
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
- Fullman, N., et al.
(författare)
-
Measuring progress and projecting attainment on the basis of past trends of the health-related Sustainable Development Goals in 188 countries: an analysis from the Global Burden of Disease Study 2016
- 2017
-
Ingår i: Lancet. - 0140-6736 .- 1474-547X. ; 390:10100, s. 1423-1459
-
Tidskriftsartikel (refereegranskat)abstract
- Background The UN's Sustainable Development Goals (SDGs) are grounded in the global ambition of "leaving no one behind". Understanding today's gains and gaps for the health-related SDGs is essential for decision makers as they aim to improve the health of populations. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016), we measured 37 of the 50 health-related SDG indicators over the period 1990-2016 for 188 countries, and then on the basis of these past trends, we projected indicators to 2030. Methods We used standardised GBD 2016 methods to measure 37 health-related indicators from 1990 to 2016, an increase of four indicators since GBD 2015. We substantially revised the universal health coverage (UHC) measure, which focuses on coverage of essential health services, to also represent personal health-care access and quality for several non-communicable diseases. We transformed each indicator on a scale of 0-100, with 0 as the 2.5th percentile estimated between 1990 and 2030, and 100 as the 97.5th percentile during that time. An index representing all 37 health-related SDG indicators was constructed by taking the geometric mean of scaled indicators by target. On the basis of past trends, we produced projections of indicator values, using a weighted average of the indicator and country-specific annualised rates of change from 1990 to 2016 with weights for each annual rate of change based on out-of-sample validity. 24 of the currently measured health-related SDG indicators have defined SDG targets, against which we assessed attainment. Findings Globally, the median health-related SDG index was 56.7 (IQR 31.9-66.8) in 2016 and country-level performance markedly varied, with Singapore (86.8, 95% uncertainty interval 84.6-88.9), Iceland (86.0, 84.1-87.6), and Sweden (85.6, 81.8-87.8) having the highest levels in 2016 and Afghanistan (10.9, 9.6-11.9), the Central African Republic (11.0, 8.8-13.8), and Somalia (11.3, 9.5-13.1) recording the lowest. Between 2000 and 2016, notable improvements in the UHC index were achieved by several countries, including Cambodia, Rwanda, Equatorial Guinea, Laos, Turkey, and China; however, a number of countries, such as Lesotho and the Central African Republic, but also high-income countries, such as the USA, showed minimal gains. Based on projections of past trends, the median number of SDG targets attained in 2030 was five (IQR 2-8) of the 24 defined targets currently measured. Globally, projected target attainment considerably varied by SDG indicator, ranging from more than 60% of countries projected to reach targets for under-5 mortality, neonatal mortality, maternal mortality ratio, and malaria, to less than 5% of countries projected to achieve targets linked to 11 indicator targets, including those for childhood overweight, tuberculosis, and road injury mortality. For several of the health-related SDGs, meeting defined targets hinges upon substantially faster progress than what most countries have achieved in the past. Interpretation GBD 2016 provides an updated and expanded evidence base on where the world currently stands in terms of the health-related SDGs. Our improved measure of UHC offers a basis to monitor the expansion of health services necessary to meet the SDGs. Based on past rates of progress, many places are facing challenges in meeting defined health-related SDG targets, particularly among countries that are the worst off. In view of the early stages of SDG implementation, however, opportunity remains to take actions to accelerate progress, as shown by the catalytic effects of adopting the Millennium Development Goals after 2000. With the SDGs' broader, bolder development agenda, multisectoral commitments and investments are vital to make the health-related SDGs within reach of all populations. Copyright The Authors. Published by Elsevier Ltd. This is an Open Access article published under the CC BY 4.0 license.
|
|
| 19. |
- Piao, S. L., et al.
(författare)
-
The carbon budget of terrestrial ecosystems in East Asia over the last two decades
- 2012
-
Ingår i: Biogeosciences. - : Copernicus GmbH. - 1726-4189. ; 9:9, s. 3571-3586
-
Tidskriftsartikel (refereegranskat)abstract
- This REgional Carbon Cycle Assessment and Processes regional study provides a synthesis of the carbon balance of terrestrial ecosystems in East Asia, a region comprised of China, Japan, North and South Korea, and Mongolia. We estimate the current terrestrial carbon balance of East Asia and its driving mechanisms during 1990-2009 using three different approaches: inventories combined with satellite greenness measurements, terrestrial ecosystem carbon cycle models and atmospheric inversion models. The magnitudes of East Asia's terrestrial carbon sink from these three approaches are comparable: -0.293 +/- 0.033 PgC yr(-1) from inventory-remote sensing model-data fusion approach, -0.413 +/- 0.141 PgC yr(-1)(not considering biofuel emissions) or -0.224 +/- 0.141 PgC yr(-1) (considering biofuel emissions) for carbon cycle models, and -0.270 +/- 0.507 PgC yr(-1) for atmospheric inverse models. Here and in the following, the numbers behind +/- signs are standard deviations. The ensemble of ecosystem modeling based analyses further suggests that at the regional scale, climate change and rising atmospheric CO2 together resulted in a carbon sink of -0.289 +/- 0.135 PgC yr(-1), while land-use change and nitrogen deposition had a contribution of -0.013 +/- 0.029 PgC yr(-1) and -0.107 +/- 0.025 PgC yr(-1), respectively. Although the magnitude of climate change effects on the carbon balance varies among different models, all models agree that in response to climate change alone, southern China experienced an increase in carbon storage from 1990 to 2009, while northern East Asia including Mongolia and north China showed a decrease in carbon storage. Overall, our results suggest that about 13-27% of East Asia's CO2 emissions from fossil fuel burning have been offset by carbon accumulation in its terrestrial territory over the period from 1990 to 2009. The underlying mechanisms of carbon sink over East Asia still remain largely uncertain, given the diversity and intensity of land management processes, and the regional conjunction of many drivers such as nutrient deposition, climate, atmospheric pollution and CO2 changes, which cannot be considered as independent for their effects on carbon storage.
|
|
| 20. |
- Tang, X. X., et al.
(författare)
-
Coverage Performance of Joint Transmission for Moving Relay Enabled Cellular Networks in Dense Urban Scenarios
- 2017
-
Ingår i: IEEE Access. - 2169-3536 .- 2169-3536. ; 5, s. 13001-13009
-
Tidskriftsartikel (refereegranskat)abstract
- Communication plays a significant role in terms of providing connectivity for urban users as well as sensors in smart cities. It has been shown that better communication capability for vehicular users can be obtained by introducing moving relays (MRs). With MRs, it is possible for macro base stations and moving relays to serve non-vehicular macro-users by performing coordinated multipoint (CoMP) joint transmission (JT). A bias-based CoMP scheme for MR enabled cellular network is analyzed in this paper. Motivated by antenna design constraints, in this paper, we assume that the outdoor antenna system of the MR can only be used for the moving backhaul link, i.e., the in-vehicle antenna system is also serving the non-vehicular macro-users. Using the stochastic geometry approach, a tractable model of the network is proposed. Based on the proposed model, integral expressions for CoMP-JT probability and coverage probability of non-vehicular macro user equipment are derived. Simulations verify the accuracy of the derived expressions. The results show that the probability for macro user equipment to be served with CoMP-JT is up to 70% when the intensity of MRs is ten times that of MBSs. This paper also includes a performance comparison among the analyzed scheme and related works. CoMP-JT with MRs provides better coverage performance for nearby macro user equipment. It can be found that the coverage gain of CoMP increases when the intensity of MRs increases within a certain range. Simulation results provide insights for practical system design in smart cities, such as the optimal MR intensity and the feasibility for opening access of MRs to macro user equipment.
|
|
| 21. |
|
|
| 22. |
- Xu, X., et al.
(författare)
-
Modeling and Analyzing the Cross-tier Handover in Heterogeneous Networks
- 2017
-
Ingår i: IEEE Transactions on Wireless Communications. - 1558-2248 .- 1536-1276. ; 16:12, s. 7859-7869
-
Tidskriftsartikel (refereegranskat)abstract
- IEEE Denser deployments of heterogeneous networks (HetNets) lead to more frequent handovers, which results in a decline of user experience as well as heavy signaling overheads to the network. Therefore, the study on handover is of great importance especially in dense HetNets. In this paper, we focus on the analysis of cross-tier handover from the macro cell tier to the small cell tier, which shows the highest handover failure rate in current standards and industry studies. Using the stochastic geometry, we propose an analytical model for the cross-tier handover processes in the HetNet. Based on the derived analytical model, the closed-form expressions for the key handover performance metrics, including the handover rate, handover failure rate and ping-pong rate, are deduced as functions of the base station density, time to trigger and user mobility. Simulation results verify the accuracy of the proposed analytical model and closed-form theoretical analyses, which provide guidance for the deployments of HetNets and corresponding handover strategies.
|
|
| 23. |
- Zhong, Z. H., et al.
(författare)
-
Evidence for Whistler Waves Propagating Into the Electron Diffusion Region of Collisionless Magnetic Reconnection
- 2022
-
Ingår i: Geophysical Research Letters. - : American Geophysical Union (AGU). - 0094-8276 .- 1944-8007. ; 49:7
-
Tidskriftsartikel (refereegranskat)abstract
- Despite a growing number of observations of whistler waves in/around the reconnection diffusion region, the origin of the whistler waves in the diffusion region and their role in reconnection remain elusive. This paper investigates the whistler-mode waves within an electron-scale reconnecting current sheet observed by the Magnetospheric Multiscale mission on 23 December 2016. These whistlers were observed in both the electron diffusion region (EDR) and the immediate inflow region of the electron-scale magnetic reconnection site. The dispersion relation of these whistlers is measured and compared to predictions from linear theory for the first time in these regions. The comparison shows that the field-aligned drifting electron component critically modifies the dispersion relation of whistlers in the EDR due to the Doppler-shift effects. We demonstrate that these whistlers propagated into the EDR from outside rather than locally excited, however, they did not provide sufficiently large anomalous dissipation in this EDR.
|
|
| 24. |
|
|
| 25. |
|
|
| 26. |
- Arzoumanian, Doris, et al.
(författare)
-
Dust polarized emission observations of NGC 6334: BISTRO reveals the details of the complex but organized magnetic field structure of the high-mass star-forming hub-filament network
- 2021
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 647
-
Tidskriftsartikel (refereegranskat)abstract
- Context. Molecular filaments and hubs have received special attention recently thanks to new studies showing their key role in star formation. While the (column) density and velocity structures of both filaments and hubs have been carefully studied, their magnetic field (B-field) properties have yet to be characterized. Consequently, the role of B-fields in the formation and evolution of hub-filament systems is not well constrained. Aims. We aim to understand the role of the B-field and its interplay with turbulence and gravity in the dynamical evolution of the NGC 6334 filament network that harbours cluster-forming hubs and high-mass star formation. Methods. We present new observations of the dust polarized emission at 850 μm toward the 2 pc × 10 pc map of NGC 6334 at a spatial resolution of 0.09 pc obtained with the James Clerk Maxwell Telescope (JCMT) as part of the B-field In STar-forming Region Observations (BISTRO) survey. We study the distribution and dispersion of the polarized intensity (PI), the polarization fraction (PF), and the plane-of-The-sky B-field angle (χB_POS) toward the whole region, along the 10 pc-long ridge and along the sub-filaments connected to the ridge and the hubs. We derived the power spectra of the intensity and χBPOS along the ridge crest and compared them with the results obtained from simulated filaments. Results. The observations span 3 orders of magnitude in Stokes I and PI and 2 orders of magnitude in PF (from 0.2 to 20%). A large scatter in PI and PF is observed for a given value of I. Our analyses show a complex B-field structure when observed over the whole region ( 10 pc); however, at smaller scales (1 pc), χBPOS varies coherently along the crests of the filament network. The observed power spectrum of χBPOS can be well represented with a power law function with a slope of-1.33 ± 0.23, which is 20% shallower than that of I. We find that this result is compatible with the properties of simulated filaments and may indicate the physical processes at play in the formation and evolution of star-forming filaments. Along the sub-filaments, χBPOS rotates frombeing mostly perpendicular or randomly oriented with respect to the crests to mostly parallel as the sub-filaments merge with the ridge and hubs. This variation of the B-field structure along the sub-filaments may be tracing local velocity flows of infalling matter in the ridge and hubs. Our analysis also suggests a variation in the energy balance along the crests of these sub-filaments, from magnetically critical or supercritical at their far ends to magnetically subcritical near the ridge and hubs. We also detect an increase in PF toward the high-column density (NH2 â 1023 cm-2) star cluster-forming hubs. These latter large PF values may be explained by the increase in grain alignment efficiency due to stellar radiation from the newborn stars, combined with an ordered B-field structure. Conclusions. These observational results reveal for the first time the characteristics of the small-scale (down to 0.1 pc) B-field structure of a 10 pc-long hub-filament system. Our analyses show variations in the polarization properties along the sub-filaments that may be tracing the evolution of their physical properties during their interaction with the ridge and hubs. We also detect an impact of feedback from young high-mass stars on the local B-field structure and the polarization properties, which could put constraints on possible models for dust grain alignment and provide important hints as to the interplay between the star formation activity and interstellar B-fields.
|
|
| 27. |
|
|
| 28. |
|
|
| 29. |
|
|
| 30. |
|
|
| 31. |
- Eswaraiah, Chakali, et al.
(författare)
-
The JCMT BISTRO Survey: Revealing the Diverse Magnetic Field Morphologies in Taurus Dense Cores with Sensitive Submillimeter Polarimetry
- 2021
-
Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 912:2
-
Tidskriftsartikel (refereegranskat)abstract
- We have obtained sensitive dust continuum polarization observations at 850 μm in the B213 region of Taurus using POL-2 on SCUBA-2 at the James Clerk Maxwell Telescope as part of the B-fields in STar-forming Region Observations (BISTRO) survey. These observations allow us to probe magnetic field (B-field) at high spatial resolution (∼2000 au or ∼0.01 pc at 140 pc) in two protostellar cores (K04166 and K04169) and one prestellar core (Miz-8b) that lie within the B213 filament. Using the Davis-Chandrasekhar-Fermi method, we estimate the B-field strengths in K04166, K04169, and Miz-8b to be 38 ± 14, 44 ± 16, and 12 ± 5 μG, respectively. These cores show distinct mean B-field orientations. The B-field in K04166 is well ordered and aligned parallel to the orientations of the core minor axis, outflows, core rotation axis, and large-scale uniform B-field, in accordance with magnetically regulated star formation via ambipolar diffusion taking place in K04166. The B-field in K04169 is found to be ordered but oriented nearly perpendicular to the core minor axis and large-scale B-field and not well correlated with other axes. In contrast, Miz-8b exhibits a disordered B-field that shows no preferred alignment with the core minor axis or large-scale field. We found that only one core, K04166, retains a memory of the large-scale uniform B-field. The other two cores, K04169 and Miz-8b, are decoupled from the large-scale field. Such a complex B-field configuration could be caused by gas inflow onto the filament, even in the presence of a substantial magnetic flux.
|
|
| 32. |
|
|
| 33. |
- Hwang, Jihye, et al.
(författare)
-
The JCMT BISTRO Survey: A Spiral Magnetic Field in a Hub-filament Structure, Monoceros R2
- 2022
-
Ingår i: Astrophysical Journal. - : American Astronomical Society. - 1538-4357 .- 0004-637X. ; 941:1
-
Tidskriftsartikel (refereegranskat)abstract
- We present and analyze observations of polarized dust emission at 850 μm toward the central 1 × 1 pc hub-filament structure of Monoceros R2 (Mon R2). The data are obtained with SCUBA-2/POL-2 on the James Clerk Maxwell Telescope (JCMT) as part of the B-fields in Star-forming Region Observations survey. The orientations of the magnetic field follow the spiral structure of Mon R2, which are well described by an axisymmetric magnetic field model. We estimate the turbulent component of the magnetic field using the angle difference between our observations and the best-fit model of the underlying large-scale mean magnetic field. This estimate is used to calculate the magnetic field strength using the Davis–Chandrasekhar–Fermi method, for which we also obtain the distribution of volume density and velocity dispersion using a column density map derived from Herschel data and the C18O (J = 3 - 2) data taken with HARP on the JCMT, respectively. We make maps of magnetic field strengths and mass-to-flux ratios, finding that magnetic field strengths vary from 0.02 to 3.64 mG with a mean value of 1.0 ± 0.06 mG, and the mean critical mass-to-flux ratio is 0.47 ± 0.02. Additionally, the mean Alfvén Mach number is 0.35 ± 0.01. This suggests that, in Mon R2, the magnetic fields provide resistance against large-scale gravitational collapse, and the magnetic pressure exceeds the turbulent pressure. We also investigate the properties of each filament in Mon R2. Most of the filaments are aligned along the magnetic field direction and are magnetically subcritical.
|
|
| 34. |
- Sun, Y. H., et al.
(författare)
-
Theoretical studies on nonlinear optical properties of two newly synthesized compounds : PVPHC and DPVPA
- 2004
-
Ingår i: Chemical Physics Letters. - : Elsevier BV. - 0009-2614 .- 1873-4448. ; 394:03-jan, s. 176-181
-
Tidskriftsartikel (refereegranskat)abstract
- The nonlinear optical properties of two newly synthesized molecules 9-(4-{2-[4-(2-pyridin-4-yl-vinyl)-phenyl]-vinyl}-phenyl)-9H-carbazole (PVPHC) and diphenyl-(4-{2-[4-(2-pyridin-4-yl-vinyl)-phenyl]-vinyl}-phenyl)-amine (DPVPA) have been studied using hybrid density functional theory at B3LYP level. A few-state model, as well as response theory, have been employed to calculate their two-photon absorption cross-sections. The theoretical results are in good agreement with the experimental measurements available. It is found that the maximal two-photon absorption cross-sections of these compounds can be well described by a three-state model and both compounds have large two-photon absorption cross-section in optical regime. Strong charge-transfer process upon excitation has been revealed, indicating that these two compounds are good candidates as two-photon polymerization initiators.
|
|
| 35. |
- Sun, Y. H., et al.
(författare)
-
Theoretical studies on nonlinear optical properties of two newly synthesized compounds : EPVPC and OPVPC
- 2005
-
Ingår i: Chinese Physics. - : IOP Publishing. - 1009-1963 .- 1741-4199. ; 14:1, s. 115-119
-
Tidskriftsartikel (refereegranskat)abstract
- The nonlinear optical properties of two newly synthesized molecules 9-Ethyl-3-{2-[4-(2-Pyridin-4-yl-vinyl)-phenyl]vinyl}-9H-carbazole (EPVPC) and 9-Octadecyl-3-{2-[4-(2-Pyridin-4-yl-vinyl)-phenyl]-vinyl}-9H-carbazole (OPVPC) have been studied with hybrid density functional theory (DFT/B3LYP). The generalized few-state model is employed to calculate the two-photon absorption cross sections of the compounds. The theoretical results are in good agreement with the available experimental measurements. It is found that the maximal two-photon absorption (TPA) cross sections of the compounds can be well described by a three-state model. The numerical simulation shows that both compounds have large two-photon absorption (TPA) cross sections and, furthermore, OPVPC displays a little stronger TPA activity than EPVPC in a lower frequency region.
|
|
| 36. |
- Zhao, Q., et al.
(författare)
-
Retention of C-14-labeled multiwall carbon nanotubes by humic acid and polymers: Roles of macromolecule properties
- 2016
-
Ingår i: Carbon. - : Elsevier BV. - 0008-6223. ; 99, s. 229-237
-
Tidskriftsartikel (refereegranskat)abstract
- Developing methods to measure interactions of carbon nanotubes (CNTs) with soils and sediments and understanding the impact of soil and sediment properties on CNT deposition are essential for assessing CNT environmental risks. In this study, we utilized functionalized carbon-14 labeled nanotubes to systematically investigate retention of multiwall CNTs (MWCNTs) by 3 humic acids, 3 natural biopolymers, and 10 model solid-phase polymers, collectively termed macromolecules. Surface properties, rather than bulk properties of macromolecules, greatly influenced MWCNT retention. As shown via multiple linear regression analysis and path analysis, aromaticity and surface polarity were the two most positive factors for retention, suggesting retention was regulated by pi-pi stacking and hydrogen bonding interactions. Moreover, MWCNT deposition was irreversible. These observations may explain the high retention of MWCNT in natural soils. Moreover, our findings on the relative contribution of each macromolecule property on CNT retention provide information on macromolecule selection for removal of MWCNTs from wastewater and provide a method for measuring CNT interactions with organic macromolecules. Published by Elsevier Ltd.
|
|
| 37. |
|
|
| 38. |
- Zhu, X., et al.
(författare)
-
Biodegradation mechanism of microcystin-LR by a novel isolate of Rhizobium sp. TH and the evolutionary origin of the mlrA gene
- 2016
-
Ingår i: International Biodeterioration & Biodegradation. - : Elsevier. - 0964-8305 .- 1879-0208. ; 115, s. 17-25
-
Tidskriftsartikel (refereegranskat)abstract
- The frequent presence of microcystin (MC) in eutrophic water bodies worldwide poses a serious threat to ecosystems. Biodegradation has been extensively investigated as a main pathway for MC attenuation, and an mlr-dependent mechanism of MC degradation have been elucidated in detail. However, the evolutionary origin and the distribution of mlr genes in MC-degrading bacteria is poorly understood. In this study, a novel Rhizobium sp. TH, which is the first α-proteobacterial MC-degrading bacterium other than Sphingomonadales, was isolated. Strain TH degraded MC via the mlr-dependent mechanism with a first-order rate constant of 0.18–0.29 h−1 under near-natural conditions. The partial length mlr gene cluster was sequenced, and the function of its key gene, mlrA, was verified by heterologous expression in Escherichia coli. Phylogenetic analyses show that the mlrA gene initially arose in α-proteobacteria by vertical evolution, and the two strains from β- and γ-proteobacteria acquired it by horizontal gene transfer. Therefore, the mlrA gene mainly exists in α-proteobacteria but is seldom present in other bacteria. A pair of primers matching well with mlrA sequences reported so far were designed and could be used to determine the MC-degrading mechanism for novel isolates or to screen for MC-degrading ability among environmental samples.
|
|
| 39. |
-
- 2019
-
Tidskriftsartikel (refereegranskat)
|
|
| 40. |
- Ageron, M., et al.
(författare)
-
ANTARES : The first undersea neutrino telescope
- 2011
-
Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 656:1, s. 11-38
-
Tidskriftsartikel (refereegranskat)abstract
- The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given. (C) 2011 Elsevier B.V. All rights reserved.
|
|
| 41. |
- Ageron, M., et al.
(författare)
-
Studies of a full-scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements
- 2007
-
Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 581:3, s. 695-708
-
Tidskriftsartikel (refereegranskat)abstract
- full-scale mechanical prototype line was deployed to a depth of 2500 m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion study, line parameter data were taken using miniature autonomous data loggers and shore-based optical time domain reflectometry. Details of the mechanical prototype line, the electromechanical cable and data acquisition are presented. Data taken during the immersion study revealed deficiencies in the pressure resistance of the electromechanical cable terminations at the entry points to the electronics containers. The improvements to the termination, which have been integrated into subsequent detection lines, are discussed. The line also allowed deep-sea acoustic measurements with a prototype hydrophone system. The technical setup of this system is described, and the first results of the data analysis are presented. (c) 2007 Elsevier B.V. All rights reserved.
|
|
| 42. |
- An, Junghwa, et al.
(författare)
-
Permanent Genetic Resources added to Molecular Ecology Resources Database 1 October 2009-30 November 2009
- 2010
-
Ingår i: Molecular Ecology Resources. - : Wiley. - 1755-098X .- 1755-0998. ; 10:2, s. 404-408
-
Tidskriftsartikel (refereegranskat)abstract
- This article documents the addition of 411 microsatellite marker loci and 15 pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Acanthopagrus schlegeli, Anopheles lesteri, Aspergillus clavatus, Aspergillus flavus, Aspergillus fumigatus, Aspergillus oryzae, Aspergillus terreus, Branchiostoma japonicum, Branchiostoma belcheri, Colias behrii, Coryphopterus personatus, Cynogolssus semilaevis, Cynoglossus semilaevis, Dendrobium officinale, Dendrobium officinale, Dysoxylum malabaricum, Metrioptera roeselii, Myrmeciza exsul, Ochotona thibetana, Neosartorya fischeri, Nothofagus pumilio, Onychodactylus fischeri, Phoenicopterus roseus, Salvia officinalis L., Scylla paramamosain, Silene latifo, Sula sula, and Vulpes vulpes. These loci were cross-tested on the following species: Aspergillus giganteus, Colias pelidne, Colias interior, Colias meadii, Colias eurytheme, Coryphopterus lipernes, Coryphopterus glaucofrenum, Coryphopterus eidolon, Gnatholepis thompsoni, Elacatinus evelynae, Dendrobium loddigesii Dendrobium devonianum, Dysoxylum binectariferum, Nothofagus antarctica, Nothofagus dombeyii, Nothofagus nervosa, Nothofagus obliqua, Sula nebouxii, and Sula variegata. This article also documents the addition of 39 sequencing primer pairs and 15 allele specific primers or probes for Paralithodes camtschaticus.
|
|
| 43. |
- Astier, P., et al.
(författare)
-
Extending the supernova Hubble diagram to z similar to 1.5 with the Euclid space mission
- 2014
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 572, s. A80-
-
Tidskriftsartikel (refereegranskat)abstract
- We forecast dark energy constraints that could be obtained from a new large sample of Type Ia supernovae where those at high redshift are acquired with the Euclid space mission. We simulate a three-prong SN survey: a z < 0.35 nearby sample (8000 SNe), a 0.2 < z < 0.95 intermediate sample (8800 SNe), and a 0.75 < z < 1.55 high-z sample (1700 SNe). The nearby and intermediate surveys are assumed to be conducted from the ground, while the high-z is a joint ground-and space-based survey. This latter survey, the Dark Energy Supernova Infra-Red Experiment (DESIRE), is designed to fit within 6 months of Euclid observing time, with a dedicated observing programme. We simulate the SN events as they would be observed in rolling-search mode by the various instruments, and derive the quality of expected cosmological constraints. We account for known systematic uncertainties, in particular calibration uncertainties including their contribution through the training of the supernova model used to fit the supernovae light curves. Using conservative assumptions and a 1D geometric Planck prior, we find that the ensemble of surveys would yield competitive constraints: a constant equation of state parameter can be constrained to sigma(omega) = 0.022, and a Dark Energy Task Force figure of merit of 203 is found for a two-parameter equation of state. Our simulations thus indicate that Euclid can bring a significant contribution to a purely geometrical cosmology constraint by extending a high-quality SN Ia Hubble diagram to z similar to 1.5. We also present other science topics enabled by the DESIRE Euclid observations.
|
|
| 44. |
- Butler-Laporte, G, et al.
(författare)
-
Exome-wide association study to identify rare variants influencing COVID-19 outcomes: Results from the Host Genetics Initiative
- 2022
-
Ingår i: PLoS genetics. - : Public Library of Science (PLoS). - 1553-7404 .- 1553-7390. ; 18:11, s. e1010367-
-
Tidskriftsartikel (refereegranskat)abstract
- Host genetics is a key determinant of COVID-19 outcomes. Previously, the COVID-19 Host Genetics Initiative genome-wide association study used common variants to identify multiple loci associated with COVID-19 outcomes. However, variants with the largest impact on COVID-19 outcomes are expected to be rare in the population. Hence, studying rare variants may provide additional insights into disease susceptibility and pathogenesis, thereby informing therapeutics development. Here, we combined whole-exome and whole-genome sequencing from 21 cohorts across 12 countries and performed rare variant exome-wide burden analyses for COVID-19 outcomes. In an analysis of 5,085 severe disease cases and 571,737 controls, we observed that carrying a rare deleterious variant in the SARS-CoV-2 sensor toll-like receptor TLR7 (on chromosome X) was associated with a 5.3-fold increase in severe disease (95% CI: 2.75–10.05, p = 5.41x10-7). This association was consistent across sexes. These results further support TLR7 as a genetic determinant of severe disease and suggest that larger studies on rare variants influencing COVID-19 outcomes could provide additional insights.
|
|
| 45. |
- Cao, Hong Min, et al.
(författare)
-
The loud and the quiet: Searching for radio counterparts of two radio-weak BL Lac candidates with VLBI
- 2019
-
Ingår i: Monthly Notices of the Royal Astronomical Society: Letters. - : Oxford University Press (OUP). - 1745-3925 .- 1745-3933. ; 482:1, s. L34-L39
-
Tidskriftsartikel (refereegranskat)abstract
- BL Lac objects are known to have compact jets inclined to our line of sight at a small angle, showing prominent radio emission. Two radio-weak BL Lac candidates with no counterparts in current radio surveys were recently reported by Massaro et al. Both sources were selected as candidate low-energy counterparts of unassociated Fermi γ -ray sources. We carried out very long baseline interferometry (VLBI) observations with the European VLBI Network (EVN) at 5 GHz to explore their radio properties at the milliarcsecond (mas) scale. One target, J1410+7405, is clearly detected with the EVN. Its measured 5-GHz flux density, 2.4 mJy, is consistent with recent interferometricmeasurementswith theKarlG. JanskyVery LargeArray, suggesting that the radio emission is confined to the inner ≲10-mas region. J1410+7405 is therefore identified as a radio-loud jetted active galactic nucleus, and its brightness temperature exceeds ~109 K. Its properties are similar to those of other γ -ray-detected BL Lac objects. On the other hand, the second target, J0644+6031, remains undetected with the EVN with a 6s brightness upper limit of 0.12 mJy beam-1. This source is thus radio-quiet, confirming its peculiarity, or possibly questioning its BL Lac nature.
|
|
| 46. |
- Carlson, A. D., et al.
(författare)
-
A new evaluation of the neutron data standards
- 2017
-
Ingår i: ND 2016. - : EDP Sciences. - 9782759890200
-
Konferensbidrag (refereegranskat)abstract
- Evaluations are being done for the H(n,n), 6Li(n,t), 10B(n,αγ), 10B(n,α), C(n,n), Au(n,γ), 235U(n,f) and 238U(n,f) standard cross sections. Evaluations are also being done for data that are not traditional standards including: the Au(n,γ) cross section at energies below where it is considered a standard; reference cross sections for prompt gamma-ray production in fast neutron-induced reactions; reference cross sections for very high energy fission cross sections; the 235U thermal neutron fission spectrum and the 252Cf spontaneous fission neutron spectrum and the thermal constants.
|
|
| 47. |
- Carlson, A. D., et al.
(författare)
-
Evaluation of the Neutron Data Standards
- 2018
-
Ingår i: Nuclear Data Sheets. - : Elsevier BV. - 0090-3752 .- 1095-9904. ; 148, s. 143-188
-
Tidskriftsartikel (refereegranskat)abstract
- With the need for improving existing nuclear data evaluations, (e.g., ENDF/B-VIII.0 and JEFF-3.3 releases) the first step was to evaluate the standards for use in such a library. This new standards evaluation made use of improved experimental data and some developments in the methodology of analysis and evaluation. In addition to the work on the traditional standards, this work produced the extension of some energy ranges and includes new reactions that are called reference cross sections. Since the effort extends beyond the traditional standards, it is called the neutron data standards evaluation. This international effort has produced new evaluations of the following cross section standards: the H(n,n), Li-6(n,t), B-10(n, alpha), B-10(n,alpha(1)gamma), C-nat(n,n), Au(n,gamma), U-235(n,f) and U-238(n,f). Also in the evaluation process the U-238(n,gamma) and Pu-239(n,f) cross sections that are not standards were evaluated. Evaluations were also obtained for data that are not traditional standards: the Maxwellian spectrum averaged cross section for the Au(n,gamma) cross section at 30 keV; reference cross sections for prompt gamma-ray production in fast neutron-induced reactions; reference cross sections for very high energy fission cross sections; the Cf-252 spontaneous fission neutron spectrum and the U-235 prompt fission neutron spectrum induced by thermal incident neutrons; and the thermal neutron constants. The data and covariance matrices of the uncertainties were obtained directly from the evaluation procedure.
|
|
| 48. |
- Dang, D. F., et al.
(författare)
-
Manipulating backbone structure with various conjugated spacers to enhance photovoltaic performance of D-A-type two-dimensional copolymerse
- 2014
-
Ingår i: Organic Electronics: physics, materials, applications. - : Elsevier BV. - 1566-1199. ; 15:11, s. 2876-2884
-
Tidskriftsartikel (refereegranskat)abstract
- A class of low band-gap two-dimensional conjugated polymers of PBDTT-FQ PBDTT-TQ PBDTT-BTQ and PBDTT-TTQ was designed and synthesized, which contains the same di(alkylthiophene)-substituted benzo[1,2-b:4,5-b']dithiophene (BDTT) and 6,7-difluoro-quinoxaline (Q) units, as well as various conjugated spacers of furan, thiophene, bithiophene and thieno[3,2-b]thiophene in the main chain. Significant effect of the varied spacers between the BDTT and Q units on the thermal, optical, electrochemical and photovoltaic properties was investigated and observed for these two-dimensional copolymers in the polymer solar cells. The maximum power conversion efficiency of 5.9% with a short circuit current of 13.7 mA/cm(2) and a fill factor of 0.56 was obtained for the PBDTT-TQ with thiophene spacer in the bulk hetero-junction PSCs using [6,6]-phenyl-C-71-butyric acid methyl ester as acceptor.
|
|
| 49. |
- Du, QQ, et al.
(författare)
-
Generation of mega brown adipose tissue in adults by controlling brown adipocyte differentiation in vivo
- 2022
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 1091-6490. ; 119:40, s. e2203307119-
-
Tidskriftsartikel (refereegranskat)abstract
- Brown adipose tissue (BAT) is a highly specialized adipose tissue in its immobile location and size during the entire adulthood. In response to cold exposure and other β3-adrenoreceptor stimuli, BAT commits energy consumption by nonshivering thermogenesis (NST). However, the molecular machinery in controlling the BAT mass in adults is unknown. Here, we show our surprising findings that the BAT mass and functions can be manipulated in adult animals by controlling BAT adipocyte differentiation in vivo. Platelet-derived growth factor receptor α (PDGFα) expressed in BAT progenitor cells served a signaling function to avert adipose progenitor differentiation. Genetic and pharmacological loss-of-function of PDGFRα eliminated the differentiation barrier and permitted progenitor cell differentiation to mature and functional BAT adipocytes. Consequently, an enlarged BAT mass (megaBAT) was created by PDGFRα inhibition owing to increases of brown adipocyte numbers. Under cold exposure, a microRNA-485 (miR-485) was identified as a master suppressor of the PDGFRα signaling, and delivery of miR-485 also produced megaBAT in adult animals. Noticeably, megaBAT markedly improved global metabolism, insulin sensitivity, high-fat-diet (HFD)-induced obesity, and diabetes by enhancing NST. Together, our findings demonstrate that the adult BAT mass can be increased by blocking the previously unprecedented inhibitory signaling for BAT progenitor cell differentiation. Thus, blocking the PDGFRα for the generation of megaBAT provides an attractive strategy for treating obesity and type 2 diabetes mellitus (T2DM).
|
|
| 50. |
|
|
