Remote observations of the solar photospheric light scattered by electrons (the K-corona) and dust (the F-corona or zodiacal light) have been made from the ground during eclipses
and from space at ...distances as small as 0.3 astronomical units
to the Sun. Previous observations
of dust scattering have not confirmed the existence of the theoretically predicted dust-free zone near the Sun
. The transient nature of the corona has been well characterized for large events, but questions still remain (for example, about the initiation of the corona
and the production of solar energetic particles
) and for small events even its structure is uncertain
. Here we report imaging of the solar corona
during the first two perihelion passes (0.16-0.25 astronomical units) of the Parker Solar Probe spacecraft
, each lasting ten days. The view from these distances is qualitatively similar to the historical views from ground and space, but there are some notable differences. At short elongations, we observe a decrease in the intensity of the F-coronal intensity, which is suggestive of the long-sought dust free zone
. We also resolve the fine-scale plasma structure of very small eruptions, which are frequently ejected from the Sun. These take two forms: the frequently observed magnetic flux ropes
and the predicted, but not yet observed, magnetic islands
arising from the tearing-mode instability in the current sheet. Our observations of the coronal streamer evolution confirm the large-scale topology of the solar corona, but also reveal that, as recently predicted
, streamers are composed of yet smaller substreamers channelling continual density fluctuations at all visible scales.
The incidence of stroke is predicted to rise because of the rapidly ageing population. However, over the past two decades, findings of randomised trials have identified several interventions that are ...effective in prevention of stroke. Reliable data on time-trends in stroke incidence, major risk factors, and use of preventive treatments in an ageing population are required to ascertain whether implementation of preventive strategies can offset the predicted rise in stroke incidence. We aimed to obtain these data.
We ascertained changes in incidence of transient ischaemic attack and stroke, risk factors, and premorbid use of preventive treatments from 1981–84 (Oxford Community Stroke Project; OCSP) to 2002–04 (Oxford Vascular Study; OXVASC).
Of 476 patients with transient ischaemic attacks or strokes in OXVASC, 262 strokes and 93 transient ischaemic attacks were incident events. Despite more complete case-ascertainment than in OCSP, age-adjusted and sex-adjusted incidence of first-ever stroke fell by 29% (relative incidence 0·71, 95% CI 0·61–0·83, p=0·0002). Incidence declined by more than 50% for primary intracerebral haemorrhage (0·47, 0·27–0·83, p=0·01) but was unchanged for subarachnoid haemorrhage (0·83, 0·44–1·57, p=0·57). Thus, although 28% more incident strokes (366 vs 286) were expected in OXVASC due to demographic change alone (33% increase in those aged 75 or older), the observed number fell (262 vs 286). Major reductions were recorded in mortality rates for incident stroke (0.63, 0.44–0.90, p=0.02) and in incidence of disabling or fatal stroke (0·60, 0·50–0·73, p<0·0001), but no change was seen in case-fatality due to incident stroke (17·2% vs 17·8%; age and sex adjusted relative risk 0·85, 95% CI 0·57-1·28, p=0·45). Comparison of premorbid risk factors revealed substantial reductions in the proportion of smokers, mean total cholesterol, and mean systolic and diastolic blood pressures and major increases in premorbid treatment with antiplatelet, lipid-lowering, and blood pressure lowering drugs (all p<0.0001).
The age-specific incidence of major stroke in Oxfordshire has fallen by 40% over the past 20 years in association with increased use of preventive treatments and major reductions in premorbid risk factors.
Aims
. We present the design and pre-launch performance of the Solar Orbiter Heliospheric Imager (SoloHI) which is an instrument prepared for inclusion in the ESA/NASA Solar Orbiter mission, ...currently scheduled for launch in 2020.
Methods
. The goal of this paper is to provide details of the SoloHI instrument concept, design, and pre-flight performance to give the potential user of the data a better understanding of how the observations are collected and the sources that contribute to the signal.
Results
. The paper discusses the science objectives, including the SoloHI-specific aspects, before presenting the design concepts, which include the optics, mechanical, thermal, electrical, and ground processing. Finally, a list of planned data products is also presented.
Conclusions
. The performance measurements of the various instrument parameters meet or exceed the requirements derived from the mission science objectives. SoloHI is poised to take its place as a vital contributor to the science success of the Solar Orbiter mission.
In this study, the androgen-receptor inhibitor enzalutamide improved progression-free and overall survival in men with castration-resistant metastatic prostate cancer who had not received ...chemotherapy.
Prostate cancer is the most commonly diagnosed cancer and the sixth leading cause of cancer-related death among men worldwide.
1
Strategies to block androgen-receptor signaling have formed the backbone of prostate-cancer therapy since the first description of the hormonal dependence of this cancer in 1941.
2
Advances in endocrine therapies have improved survival in men with high-risk locoregional prostate cancer.
3
,
4
However, new hormonal agents have been shown to extend survival in men with metastatic castration-resistant disease.
5
–
9
In most patients who are treated for advanced recurrent prostate cancer with androgen-deprivation therapy (comprising a luteinizing hormone–releasing hormone LHRH analogue or orchiectomy with . . .
Coronal Mass ejections (CMEs) are enormous eruptions of magnetized plasma expelled from the Sun into the interplanetary space, over the course of hours to days. They can create major disturbances in ...the interplanetary medium and trigger severe magnetic storms when they collide with the Earth's magnetosphere. It is important to know their real speed, propagation direction and 3-D configuration in order to accurately predict their arrival time at the Earth. Using data from the SECCHI coronagraphs onboard the STEREO mission, which was launched in October 2006, we can infer the propagation direction and the 3-D structure of such events. In this review, we first describe different techniques that were used to model the 3-D configuration of CMEs in the coronagraph field of view (up to 15 R⊙). Then, we apply these techniques to different CMEs observed by various coronagraphs. A comparison of results obtained from the application of different reconstruction algorithms is presented and discussed.
Palaeolithic cave art in Borneo Aubert, M; Setiawan, P; Oktaviana, A A ...
Nature (London),
12/2018, Letnik:
564, Številka:
7735
Journal Article
Recenzirano
Figurative cave paintings from the Indonesian island of Sulawesi date to at least 35,000 years ago (ka) and hand-stencil art from the same region has a minimum date of 40 ka
. Here we show that ...similar rock art was created during essentially the same time period on the adjacent island of Borneo. Uranium-series analysis of calcium carbonate deposits that overlie a large reddish-orange figurative painting of an animal at Lubang Jeriji Saléh-a limestone cave in East Kalimantan, Indonesian Borneo-yielded a minimum date of 40 ka, which to our knowledge is currently the oldest date for figurative artwork from anywhere in the world. In addition, two reddish-orange-coloured hand stencils from the same site each yielded a minimum uranium-series date of 37.2 ka, and a third hand stencil of the same hue has a maximum date of 51.8 ka. We also obtained uranium-series determinations for cave art motifs from Lubang Jeriji Saléh and three other East Kalimantan karst caves, which enable us to constrain the chronology of a distinct younger phase of Pleistocene rock art production in this region. Dark-purple hand stencils, some of which are decorated with intricate motifs, date to about 21-20 ka and a rare Pleistocene depiction of a human figure-also coloured dark purple-has a minimum date of 13.6 ka. Our findings show that cave painting appeared in eastern Borneo between 52 and 40 ka and that a new style of parietal art arose during the Last Glacial Maximum. It is now evident that a major Palaeolithic cave art province existed in the eastern extremity of continental Eurasia and in adjacent Wallacea from at least 40 ka until the Last Glacial Maximum, which has implications for understanding how early rock art traditions emerged, developed and spread in Pleistocene Southeast Asia and further afield.
Context.
The launch of Parker Solar Probe (PSP) in 2018, followed by Solar Orbiter (SO) in February 2020, has opened a new window in the exploration of solar magnetic activity and the origin of the ...heliosphere. These missions, together with other space observatories dedicated to solar observations, such as the Solar Dynamics Observatory, Hinode, IRIS, STEREO, and SOHO, with complementary in situ observations from WIND and ACE, and ground based multi-wavelength observations including the DKIST observatory that has just seen first light, promise to revolutionize our understanding of the solar atmosphere and of solar activity, from the generation and emergence of the Sun’s magnetic field to the creation of the solar wind and the acceleration of solar energetic particles.
Aims.
Here we describe the scientific objectives of the PSP and SO missions, and highlight the potential for discovery arising from synergistic observations. Here we put particular emphasis on how the combined remote sensing and in situ observations of SO, that bracket the outer coronal and inner heliospheric observations by PSP, may provide a reconstruction of the solar wind and magnetic field expansion from the Sun out to beyond the orbit of Mercury in the first phases of the mission. In the later, out-of-ecliptic portions of the SO mission, the solar surface magnetic field measurements from SO and the multi-point white-light observations from both PSP and SO will shed light on the dynamic, intermittent solar wind escaping from helmet streamers, pseudo-streamers, and the confined coronal plasma, and on solar energetic particle transport.
Methods.
Joint measurements during PSP–SO alignments, and magnetic connections along the same flux tube complemented by alignments with Earth, dual PSP–Earth, and SO-Earth, as well as with STEREO-A, SOHO, and BepiColumbo will allow a better understanding of the in situ evolution of solar-wind plasma flows and the full three-dimensional distribution of the solar wind from a purely observational point of view. Spectroscopic observations of the corona, and optical and radio observations, combined with direct in situ observations of the accelerating solar wind will provide a new foundation for understanding the fundamental physical processes leading to the energy transformations from solar photospheric flows and magnetic fields into the hot coronal plasma and magnetic fields and finally into the bulk kinetic energy of the solar wind and solar energetic particles.
Results.
We discuss the initial PSP observations, which already provide a compelling rationale for new measurement campaigns by SO, along with ground- and space-based assets within the synergistic context described above.
Abstract Aims/hypothesis This study was conducted to determine the optimal monthly subcutaneous dose of canakinumab (a human monoclonal anti-human IL-1β antibody) needed to improve glucose control in ...metformin-treated patients with type 2 diabetes mellitus (T2DM). Methods This was a parallel-group, randomized, double-blind, multicentre, placebo-controlled study designed to assess the effect on HbA1c and the safety/tolerability of four monthly doses of canakinumab (5, 15, 50, or 150 mg) as an add-on to metformin over 4 months. Results Patients ( n = 551; mean age 54.1 years; mean baseline HbA1c 7.4%) were randomized and treated in a double-blind fashion to canakinumab 5 mg ( n = 93), 15 mg ( n = 95), 50 mg ( n = 92), 150 mg ( n = 92) or placebo ( n = 179) monthly. There was no dose response detected between active canakinumab doses, but all doses numerically lowered HbA1c (primary endpoint) from baseline between 0.19% and 0.31% (placebo-unadjusted), with maximal effect noted in the 50 mg dose of canakinumab (−0.18% difference vs placebo; multiplicity-adjusted, P = 0.13902) as reported earlier (Ridker et al., 2012). No other glycaemic control parameters (FPG, fasting insulin, plasma glucose AUC0–4h , 2-h PPG, peak glucose, C-peptide AUC0–4h , peak C-peptide, insulin AUC0–4h , peak insulin, ISR0–2h , HOMA-β and HOMA-IR) showed any meaningful changes by canakinumab therapy. Canakinumab treatment was safe and well tolerated. There were no relevant differences in adverse events between the canakinumab and placebo groups. Conclusions/interpretation A 4-month course of monthly canakinumab (50 mg) produced a numerical reduction of HbA1c in T2DM patients on metformin, potentially by improving beta-cell function. The safety and tolerability profile of canakinumab was consistent with prior trials. Trial registration Registry: http://www.ClinicalTrials.gov , Registration No.: NCT00900146
Acidity is a critical component of the apple fruit consumption experience. In previous biparental family studies, two large-effect acidity QTLs were reported using freshly harvested fruit. Objectives ...of this study were to determine the number and location of QTLs for acidity variation in a large apple breeding program and ascertain the quantitative effects and breeding relevance of QTL allelic combinations at harvest and after commercially relevant periods of cold storage. Pedigree-connected germplasm of 16 full-sib families representing nine important breeding parents, genotyped for the 8K SNP array, was assessed for titratable acidity at harvest and after 10- and 20-week storage treatments, for three successive seasons. Using pedigree-based QTL mapping software, FlexQTL™, evidence was found for only two QTLs, on linkage groups 16 (the reported
Ma
locus) and LG 8 (here called
Ma3
) that jointly explained 66 ± 5% of the phenotypic variation. An additive allele dosage model for the two QTLs effectively explained most acidity variation, with an average of + 1.8 mg/L at harvest per high-acidity allele. The more high-acidity alleles, the faster the depletion with storage, with all combinations appearing to eventually converge to a common baseline. All parent cultivars and selections had one or two of the four possible high-acidity alleles. Each QTL had a rare second high-acidity allele with stronger or reduced effect. Diagnostic SNP markers were identified for QTL alleles derived from distinct sources. Combined QTL effects highlighted utility of the DNA-based information in new cultivar development for targeting desired fruit acidity levels before or after storage.
The genetic programs that promote retention of self-renewing leukemia stem cells (LSCs) at the apex of cellular hierarchies in acute myeloid leukemia (AML) are not known. In a mouse model of human ...AML, LSCs exhibit variable frequencies that correlate with the initiating MLL oncogene and are maintained in a self-renewing state by a transcriptional subprogram more akin to that of embryonic stem cells (ESCs) than to that of adult stem cells. The transcription/chromatin regulatory factors Myb, Hmgb3, and Cbx5 are critical components of the program and suffice for Hoxa/Meis-independent immortalization of myeloid progenitors when coexpressed, establishing the cooperative and essential role of an ESC-like LSC maintenance program ancillary to the leukemia-initiating MLL/Hox/Meis program. Enriched expression of LSC maintenance and ESC-like program genes in normal myeloid progenitors and poor-prognosis human malignancies links the frequency of aberrantly self-renewing progenitor-like cancer stem cells (CSCs) to prognosis in human cancer.
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