Abstract
Ultraviolet spectra of Comet 96/P Machholz were obtained during its 2002 perihelion with the UltraViolet Coronagraph Spectrometer instrument on board the SOHO satellite. Emission from H
i
, ...C
ii
, C
iii
, and O
i
is detected near the nucleus. The outgassing rate is in line with the value extrapolated from rates at larger distances from the Sun, and abundances of C and O are estimated. Reconstructed images show a nearly spherical cloud of H
i
Ly
α
emission and an ion tail seen in C
iii
. Radiation pressure on the hydrogen atoms produces a modest distortion of the shape of the Ly
α
cloud as seen from SOHO and Doppler shifts up to 30 km s
−1
in the outer parts of the cloud. We estimate a ratio of C to H
2
O similar to what is observed in other comets, so low carbon abundance does not account for the anomalously low C
2
and C
3
ratios to NH
2
observed at optical wavelengths.
Faraday rotation measures (RMs) of the polarized emission from extragalactic radio sources occulted by the coronal plasma were used to infer the radial profile of the inner heliospheric magnetic ...field near the solar minimum. By inverting LASCO/SOHO polarized brightness (pB) data taken during the observations in May 1997, we retrieved the electron density distribution along the lines of sight to the sources, which allowed us to separate the two plasma properties that contribute to the observed RMs. By comparing the observed RM values with those theoretically predicted by a power law model of the radial component of the coronal magnetic field using a best-fitting procedure, we found that the radial component of the inner heliospheric magnetic field can be nicely approximated by a power law of the form Br = 3.76 r-2.29 G in a range of heights from about 5 to 14 R⊙. Finally, our analysis suggests that the radial computation of the potential field source surface model from the Wilcox Solar Observatory is the preferred choice near solar minimum assuming a radial field in the photosphere and a source surface located at Rss = 2.5 R⊙.
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Despite recent improvements in survival due to advances in treatment, the quality of life of patients with lymphoma may be compromised by the long-term complications of chemotherapy and steroid ...therapy. Among these, a potentially relevant problem is bone loss and the development of fragility fractures.
To provide further evidence of clinical or subclinical skeletal complications in correlation with biological variables and markers of bone disease in patients with complete response to therapy.
A cross-sectional observational study was conducted on subjects diagnosed with lymphoma with subsequent antineoplastic treatment, disease status after therapy defined as complete response disease for at least a year now. We performed: blood chemistry tests, imaging techniques and screening tools for the assessment of functional status and quality of life (SARC-F and mini-Osteoporosis Quality of Life).
Approximately 50% of patients had osteoporosis, with a prevalence of vertebral fractures of 65.5%. In most patients, we found hypovitaminosis D and high levels of parathyroid hormone (PTH). Furthermore, a statistically significant association was observed between high PTH levels and previous lymphoma treatment. Finally, the Mini-Osteoporosis Quality of life (mini-OQLQ) questionnaire demonstrated a loss of quality of life as a consequence of the change in bone status.
Patient treatment design for personalized chemotherapy would be desirable to reduce late effects on bone. Also, early prevention programs need to be applied before starting treatment. The most benefited subpopulations could be not only elderly but also young patients.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this work, we focus on the analysis of a coronal mass ejection (CME) driven shock observed by the Solar and Heliospheric Observatory/Large Angle and Spectrometric Coronagraph Experiment. We show ...that white-light coronagraphic images can be employed to estimate the compression ratio X = Delta *r d / Delta *r u all along the front of CME-driven shocks. X increases from the shock flanks (where X 1.2) to the shock center (where X 3.0 is maximum). From the estimated X values, we infer the Alfven Mach number for the general case of an oblique shock. It turns out that only a small region around the shock center is supercritical at earlier times, while higher up in the corona the whole shock becomes subcritical. This suggests that CME-driven shocks could be efficient particle accelerators at the initiation phases of the event, while at later times they progressively loose energy, also losing their capability to accelerate high-energy particles. This result has important implications on the localization of particle acceleration sites and in the context of predictive space weather studies.
We analyzed the band splitting of a Type II radio burst observed on 1997 May 12 by ground- and space-based radio spectrometers. Type II radio emission is the most evident signature of coronal shock ...waves and the observed band splitting is generally interpreted as due to plasma emission from both upstream and downstream shock regions. From the inferred compression ratio we estimated, using the magnetohydrodynamic (MHD) Rankine-Hugoniot relations, the ambient Alfvén Mach number. By means of the electron density obtained by inverting white-light polarized brightness (pB) coronagraph data and the shock speed inferred from the Type II frequency drift, we finally derived a radial profile for the magnetic field strength in the middle corona. The result was compared with the field profile obtained in May 1997 (but above ~5 R⊙) with Faraday rotation measurements of extragalactic radio sources occulted by the corona. The power law of the form B(r) = 3.76 r-2.29 G inferred in that work nicely describes the combined set of data in a wide range of heliocentric distances (r ≈ 1.8−14 R⊙).
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Mechanical stimulation of trigger hairs on the adaxial surface of the trap of Dionaea muscipula leads to the generation of action potentials and to rapid leaf movement. After rapid closure secures ...the prey, the struggle against the trigger hairs results in generation of further action potentials which inhibit photosynthesis. A detailed analysis of chlorophyll a fluorescence kinetics and gas exchange measurements in response to generation of action potentials in irritated D. muscipula traps was used to determine the 'site effect' of the electrical signal-induced inhibition of photosynthesis. Irritation of trigger hairs and subsequent generation of action potentials resulted in a decrease in the effective photochemical quantum yield of photosystem II (Φ PSII ) and the rate of net photosynthesis (A N ). During the first seconds of irritation, increased excitation pressure in photosystem II (PSII) was the major contributor to the decreased Φ PSII . Within ∼1 min, non-photochemical quenching (NPQ) released the excitation pressure at PSII. Measurements of the fast chlorophyll a fluorescence transient (O-J-I-P) revealed a direct impact of action potentials on the charge separation–recombination reactions in PSII, although the effect seems to be small rather than substantial. All the data presented here indicate that the main primary target of the electrical signal-induced inhibition of photosynthesis is the dark reaction, whereas the inhibition of electron transport is only a consequence of reduced carboxylation efficiency. In addition, the study also provides valuable data confirming the hypothesis that chlorophyll a fluorescence is under electrochemical control.
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In this work, we apply multichannel singular spectrum analysis (MSSA), a data-adaptive, multivariate, non-parametric technique that simultaneously exploits the spatial and temporal correlations of ...the input data to extract common modes of variability, to investigate the intermediate quasi-periodicities of the Fe
xiv
green coronal emission line at 530.3 nm for the period between 1944 and 2008. Our analysis reveals several significant mid-term periodicities in a range from about one to four years that are consistent with the so-called quasi-biennial oscillations (QBOs), which have been detected by several authors using different data sets and analysis methods. These QBOs display amplitudes varying significantly with time and latitude over the six solar cycles (18 to 23) covered by this study. A clear North–South asymmetry is detected both in their intensity and period distribution, with a net predominance of spectral power in the active-region belt of the northern hemisphere. On the other hand, while the QBOs with periods
≳
1.7
years are particularly intense around the polar regions and therefore related to the global magnetic field, the ones with shorter periods are mainly generated at mid-latitudes, in correspondence with the emergence of active regions. Our findings indicate that the North–South asymmetry manifested in the uneven latitudinal distribution of QBOs is a fundamental, albeit puzzling, characteristic of solar activity.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Tumor regression after antiviral therapy (AT) is in favor of an etiological role of hepatitis C virus (HCV) in non-Hodgkin's B-cell lymphomas (NHL).
We carried out a cohort study of 704 consecutive ...HIV-negative, HCV-positive patients with indolent NHL diagnosed and treated from 1993 to 2009 in 39 centers of the Fondazione Italiana Linfomi; 134 patients were managed with AT for lymphoma control.
For entire cohort, 5-year overall survival (OS) was 78% 95% confidence interval (CI): 74%–82% and 5-year progression-free survival (PFS) was 48% (95% CI: 44%–53%). In multivariate analysis, the use of AT during the patients’ life had positive impact on OS. Forty-four of the 100 patients treated with first-line AT achieved a complete remission (CR) and 33 a partial response (PR). HCV-RNA clearance was achieved in 80 patients and was related to lymphoma response. At a median follow-up of 3.6 years, 5-year PFS was 63% (95% CI: 50%–73%). CR + PR rate was 85% with AT as second-line treatment.
AT produces HCV-RNA clearance and consequent tumor regression in most patients with HCV-related indolent NHL. AT used at any time is associated with improved OS. Consequently, AT can be considered an option for patients with indolent lymphomas who do not need immediate cytoreductive treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In the companion Paper I, Mancuso & Raymond (2004) investigated the relationship between type II and coronal mass ejection (CME) activity for a sample of twenty-nine CME/shock events that occurred ...between March and December 1999. Most of the events appeared to lead the type II emission locations by several minutes and the two sets of speeds were not well- correlated, in apparent disagreement with a CME-driven origin interpretation of the coronal shocks. The above discrepancies were attributed to an artifact effect due to geometry, favoring emission at the flanks of the CME leading edges in correspondence with denser low-Alfven-speed coronal structures, where shock strengths are enhanced. An important caveat in the analysis carried out in Paper I is that the conclusions that supported the CME-driven shock front-flank scenario were based on sunward-extrapolated CME trajectories deduced from the analysis of Large Angle and Spectrometric Coronagraph (SOHO/LASCO) observations in the outer corona that might not be accurate at low coronal heights where significant accelerations should be present before the CMEs acquire the speeds inferred by coronagraphic images. In the present paper, we re-examine the above relationship for a subset of ten events by integrating the LASCO measurements with ancillary CME observations taken by other instruments (MLSO/Mk4, SOHO/EIT, and UVCS) at coronal heights comparable to the typical type II radio emissions (1.2-2.5 R_{\odot}). We investigate the bias introduced in the sunward extrapolation of LASCO data and discuss whether the presence of previously undetected CME accelerations at low coronal heights might have affected the conclusions put forth in the CME-driven shock front-flank scenario proposed in Paper I. We show that the new set of observations neither solve the problem of the timing between CMEs and shocks nor improve the correlation between CME and shock speeds, although acceleration effects are found to be important at the typical metric type II heights and must be taken into account for a proper analysis of the CME/shock relationship.
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The study of electrical network systems, integrated with chemical signaling networks, is becoming a common trend in contemporary biology. Classical techniques are limited to the assessment of signals ...from doublets or triplets of cells at a fixed temporal bin width. At present, full characteristics of the electrical network distribution and dynamics in plant cells and tissues has not been established. Here, a 60-channels multielectrode array (MEA) is applied to study spatiotemporal characteristics of the electrical network activity of the root apex. Both intense spontaneous electrical activities and stimulation-elicited bursts of locally propagating electrical signals have been observed. Propagation of the spikes indicates the existence of excitable traveling waves in plants, similar to those observed in non-nerve electrogenic tissues of animals. Obtained data reveal synchronous electric activities of root cells emerging in a specific root apex region. The dynamic electrochemical activity of root apex cells is proposed to continuously integrate internal and external signaling for developmental adaptations in a changing environment.
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