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Alteration and abnormal epigenetic mechanisms can lead to the aberration of normal biological functions and the occurrence of several diseases. The histone deacetylase (HDAC) family of enzymes is one of the prime regulators of epigenetic functions modifying the histone proteins, and thus, regulating epigenetics directly. HDAC1 is one of those HDACs which have important contributions to cellular epigenetics. The abnormality of HDAC is correlated to the occurrence, progression, and poor prognosis in several disease conditions namely neurodegenerative disorders, cancer cell proliferation, metastasis, chemotherapy resistance, and survival in various cancers. Therefore, the progress of potent and effective HDAC1 inhibitors is one of the prime approaches to combat such diseases. In this study, both regression and classification-based molecular modelling studies were conducted on some AR-42 derivatives as HDAC1 inhibitors to elucidate the crucial structural aspects that are responsible for regulating their biological responses. This study revealed that the molecular polarizability, van der Waals volume, the presence of aromatic rings as well as the higher number of hydrogen bond acceptors might affect prominently their inhibitory activity and might be responsible for proper fitting and interactions at the HDAC1 active site to pertain effective inhibition.

Objectives The wide spectrum of clinical outcomes to SARSCoV-2 exposure suggests that early immune responses play a pivotal role 1 We aim to describe early, longitudinal, local (nasal mucosal lining fluid) and systemic (peripheral blood) cytokine and cellular immune responses to SARS-CoV-2 in a symptomatic index case and their household contacts with detailed clinical and virological phenotyping We hypothesise that immune responses at symptom onset would correlate with outcomes Methods Participants from the London area are referred to INSTINCT study by general practitioners as suspected, or Public Health England as laboratory-confirmed, cases (ethical review details: IRAS 282820, approved 24 04 2020) Households are visited the day after identification and again on days 7, 15 and 28 Clinical and exposure questionnaires, samples of environment (surface swabs and air);oropharynx (swabs);nasal mucosa (synthetic absorptive matrix) and blood, and daily symptom diaries are collected Samples are analysed by PCR, serology, 20-plex cytokine assay and flow cytometry in institutional laboratories Results The index case was the first SARS-CoV-2 PCR-positive recruit of INSTINCT, confirmed on oropharyngeal swab 5 days after symptom onset Contacts 1 and 2, the spouse and daughter, became symptomatic 2 days after the index case and were confirmed PCR-positive 3 days after symptom onset The three PCR-positive individuals seroconverted during follow-up Contact 3, the son, remained asymptomatic, PCRand serology-negative throughout (figure 1a-b) None required hospitalisation Swabs of the kettle and fridge handles were positive for virus, while other household surfaces and air samples were negative Induction, peak and decline of interferonl-1 and IP-10 levels were captured in nasal mucosa, with lower serum levels (figures 1c-f) Conclusion These data demonstrate the ability of the INSTINCT household contact study to capture early immune responses in mild SARS-CoV-2 infection, not captured by COVID-19 hospital cohort studies Early nasal mucosal cytokine responses to SARS-CoV-2 infection are not reflected in serum The correlations observed provide cogent hypotheses that will be tested in the larger INSTINCT cohort, with implications for COVID-19 risk stratification, therapeutics, prophylaxis and vaccinology

Background: The SARS-CoV-2 Delta variant is highly transmissible and spreading globally but a detailed understanding of community transmission risks in highly vaccinated populations is lacking. Methods: Between September 2020 and August 2021, we recruited 510 community contacts of 422 UK COVID-19 cases to a cohort study. A total of 7194 upper respiratory tract (URT) samples were tested from sequential daily sampling of participants for up to 20 days. We analysed transmission risk by vaccination status for 139 contacts exposed to the Delta variant. We compared viral load (VL) trajectories from fully-vaccinated cases of Delta infection (n=19) with unvaccinated Delta (n=10), Alpha (n=39) and pre-Alpha (n=49) infections. Findings: The household secondary attack rate for fully-vaccinated contacts exposed to Delta was 19.7% (95%CI:11.6-31.3%), compared with 35.7% (95%CI:16.4-61.2%) in the unvaccinated. One third of infections in Delta-exposed contacts arose from fully-vaccinated index cases and one half of infected contacts were also fully-vaccinated. Seven transmission events between fully vaccinated index-contact pairs occurred. Genomic analysis confirmed transmission pathways between fully-vaccinated individuals within three households. Peak VL was similar in vaccinated and unvaccinated individuals with Delta variant infection but vaccinated Delta cases saw significantly faster VL decline than unvaccinated Alpha or Delta cases. Within infected individuals, faster VL growth was correlated with higher peak VL and slower decline. Interpretation: Although vaccination reduces the risk of Delta infection and causes some changes to viral kinetics, fully-vaccinated individuals with breakthrough infections have peak URT VL similar to unvaccinated cases and can efficiently transmit infection in household settings, including to fully vaccinated contacts. Funding: National Institute for Health Research (Award:NIHR200927) Declaration of Interest: The authors declare no relevant conflicts. Ethical Approval: The study was approved by the Health Research Authority (Research Ethics Committee reference: 20/NW/0231).

Cancer, the seventh most fatal disease in the world, poses a long struggle to combat this deadly disease. Economically and pharmacologically important members of Zingiberaceae plant family have helped to eradicate a number of ailments worldwide. This review highlights gingers and their wide spectrum of medicinal values focussing on their role as anticancer agents with facts and data obtained from literature review performed using PubMed, PMC, ScienceDirect, Google Scholar in a systematic way. Among the many genera underlined in this review, several species of Hedychium have emerged as potential cancer treatments with remarkable activity against different forms of tumour. However this genus is not much explored to unravel its value to medical research. Several species have been found to have cytotoxic, antiinflammatory, antioxidant and antitumour activities but not many attempts made to establish the plant principles as anticancer agents.

Vascular wilt (caused by Fusarium udum) is the most important disease of pigeonpea. Breeding strategies are needed to develop durable resistance against this pathogen. Knowledge of the genetic and pathogenic variability among isolates of F. udum is essential for effective deployment of resistance. Thirteen isolates of F. udum, collected from three regions of India were studied using cultural characteristics, molecular variability and pathogenicity. The isolates of F. udum showed variability in aerial and radial mycelium growth, colour of mycelia, substrate pigmentation, length and septation of macro- and microconidia. Amplified fragment length polymorphism (AFLP) analysis of the isolates determined seven phylogenetic groups. Pathogenesis and progress of wilt on susceptible pigeonpea cultivars varied and pathogenic isolates from the same phylogenetic group exhibited similarities in timing of infection and colonization. Non-pathogenic isolates formed separate clusters in the phylogenetic tree. The timing of fungal invasion, vascular clogging, drooping of shoots, and wilt establishment were demonstrated for the first time in pigeonpea. Vascular clogging occurred with susceptible cultivars at 78–84, 54–60, 48–60 and 36–48 h post inoculation (HPI) when inoculated with isolates of F. udum from AFLP groups 1, 3, 6 and 7, respectively. Subsequently, susceptible cultivars inoculated with isolates from the same groups exhibited wilt at 144–168, 120–144, 96–120 and 72–96 HPI, respectively. This study contributes to characterising vascular wilt of pigeonpea.

The nonlinear propagation of dust–ion acoustic (DIA) waves in an obliquely propagating magnetized dusty plasma, consisting of bi-maxwellian electrons (namely lower and higher temperature maxwellian electrons), negatively charged immobile dust grains, and inertial ions is rigorously investigated by deriving the Zakharov–Kuznetsov equation. Later, the multidimensional instability of the DIA solitary waves (DIASWs) is analyzed using the small-k perturbation technique. It is investigated that the nature of the DIASWs, the instability criterion, and the growth rate of the perturbation mode are significantly modified by the external magnetic field and the propagation directions of both the nonlinear waves and their perturbation modes. The implications of the results obtained from this investigation in space and laboratory dusty plasmas are briefly discussed.

A rigorous theoretical investigation has been made on multi-dimensional instability of obliquely propagating electrostatic dust-ion-acoustic (DIA) solitary structures in a magnetized dusty electronegative plasma which consists of Boltzmann electrons, nonthermal negative ions, cold mobile positive ions, and arbitrarily charged stationary dust. The Zakharov-Kuznetsov (ZK) equation is derived by the reductive perturbation method, and its solitary wave solution is analyzed for the study of the DIA solitary structures, which are found to exist in such a dusty plasma. The multi-dimensional instability of these solitary structures is also studied by the small-k (long wave-length plane wave) perturbation expansion technique. The combined effects of the external magnetic field, obliqueness, and nonthermal distribution of negative ions, which are found to significantly modify the basic properties of small but finite-amplitude DIA solitary waves, are examined. The external magnetic field and the propagation directions of both the nonlinear waves and their perturbation modes are found to play a very important role in changing the instability criterion and the growth rate of the unstable DIA solitary waves. The basic features (viz. speed, amplitude, width, instability, etc.) and the underlying physics of the DIA solitary waves, which are relevant to many astrophysical situations (especially, auroral plasma, Saturn’s E-ring and F-ring, Halley’s comet, etc.) and laboratory dusty plasma situations, are briefly discussed.

Introduction : Composite resins have become one of the most commonly used direct restorative materials for anterior and posterior teeth. Objectives : To observe and analyze the gap at the resin dentin interface in class II cavities restored with light cure composite resin in four experimental groups employing 37% phosphoric acid or self etching monomers and restored with /without light cure flowable composite resin. Methods: 40 sound maxillary first premolars, extracted due to orthodontic reasons was taken, distoproximal cavities were prepared and divided into 4 groups. Teeth of Group 1 was etched by 37% Phosphoric acid and light cure flowable composite resin was used, in group 2 ,two coats of self etching acidic monomer were applied and light cure flowable composite resin was used. Teeth of group 3 was etched with 37% phosphoric acid and restored without light cure flowable composite resin and in group 4, two coats of self etching acidic monomer were applied and restored without using light cure flowable composite resin material. Thermocycling was done after finishing and polishing and viewed under scanning electron microscope to observe and analyze the gap between tooth and the restoration. Result: Gap was observed at dentin-composite resin interface in all 4 groups. Results were evaluated by F-test and Manwhitney U test. No statistically significant difference was found. Conclusion: Use of flowable composite resin liner and the etching technique do not have any influence on the gap. DOI: http://dx.doi.org/10.3126/hren.v10i2.6571 Health Renaissance 2012; Vol 10 (No.2); 98-104

We demonstrate the distinct glassy transport phenomena associated with the phase separated and spin-glass-like phases of La0.85Sr0.15CoO3, prepared under different heat-treatment conditions. The low-temperature annealed (phase-separated) sample, exhibits a small change in resistance, with evolution of time, as compared to the high-temperature annealed (spin glass) one. However, the resistance change as a function of time, in both cases, is well described by a stretched exponential fit, signifying the slow dynamics. Moreover, the ultraviolet spectroscopy study evidences a relatively higher density of states in the vicinity of EF for low-temperature annealed sample and this correctly points to its less semiconducting behavior.

The dust-ion-acoustic solitary waves (DIA SWs) in an unmagnetized dusty plasma containing non-thermal electrons, cold mobile positive ions, and stationary arbitrarily (positively and negatively) charged static dust have been theoretically studied. The reductive perturbation technique has been employed to derive the Korteweg-de Vries equation, which admits SW solutions under certain conditions. It has been also shown that the basic features (amplitude, width, speed, etc.) of DIA SWs are significantly modified by the polarity of dust and non-thermal electrons. The implications of our results in space and laboratory dusty plasma situations are briefly discussed.

We present a comparative study of the near fermi-level electronic structure of single crystal and highly oriented pyrolytic graphite (HOPG). Angle resolved photoelectron spectroscopy and angle resolved inverse photoelectron spectroscopy have been used to probe the occupied and unoccupied electronic states, respectively. The band dispersions showed by single crystal graphite along its Γ K and Γ M symmetry directions were found to be in agreement with calculated band structure of graphite. The π bands of single crystal graphite were found to have a splitting of ∼ 0.5 eV at the K-point. We also observe the presence of a quasiparticle peak below EF at the K point at low temperature which indicates a strong electron–phonon coupling in graphite. In HOPG, the M and K points like features were found to be present in the same radial direction due to the superposition of the Γ M and Γ K directions. Results from our angle resolved inverse photoemission spectroscopy present the dispersion of the conduction band states, particularly the lower π ⁎ band. We have also found the presence of some non-dispersive features in both the valence and the conduction bands.

The nucleosome, which is composed of DNA wrapped around a histone octamer, is a fundamental unit of chromatin and is duplicated during the eukaryotic DNA replication process. The evolutionarily conserved histone chaperone cell cycle gene 1 (CCG1) interacting factor A/anti-silencing function 1 (CIA/Asf1) is involved in histone transfer and nucleosome reassembly during DNA replication. CIA/Asf1 has been reported to split the histone (H3–H4)2 tetramer into histone H3–H4 dimer(s) in vitro, raising a possibility that, in DNA replication, CIA/Asf1 is involved in nucleosome disassembly and the promotion of semi-conservative histone H3–H4 dimer deposition onto each daughter strand in vivo. Despite numerous studies on the functional roles of CIA/Asf1, its mechanistic role(s) remains elusive because of lack of biochemical analyses. The biochemical studies described here show that a V94R CIA/Asf1 mutant, which lacks histone (H3–H4)2 tetramer splitting activity, does not form efficiently a quaternary complex with histones H3–H4 and the minichromosome maintenance 2 (Mcm2) subunit of the Mcm2-7 replicative DNA helicase. Interestingly, the mutant enhances nascent DNA strand synthesis in a cell-free chromosomal DNA replication system using Xenopus egg extracts. These results suggest that CIA/Asf1 in the CIA/Asf1–H3–H4–Mcm2 complex, which is considered to be an intermediate in histone transfer during DNA replication, negatively regulates the progression of the replication fork.

The early solar observations of Covington (1947) established a good relation between 10.7 cm solar flux and the presence of sunspots on solar disk. The first spatially resolved observation with a two-element interferometer at arc min resolution by Kundu (1959) found that the radio source at 3 cm has a core-halo structure; the core is highly polarized and corresponds to the umbra of a sunspot with magnetic fields of several hundred gauss, and the halo corresponds to the diffuse penumbra or plage region. The coronal temperature of the core was interpreted as due to gyroresonance opacity produced by acceleration of electrons gyrating in a magnetic field. Since the opacity is produced at resonant layers where the frequency matches harmonics of the gyrofrequency, the radio observation could be utilized to measure the coronal magnetic field. Since this simple interferometric observation, the next step for solar astronomers was to use arc second resolution offered by large arrays at cm wavelengths such as Westerbrock Synthesis Radio Telescope and the Very Large Array, which were primarily built for cosmic radio research. Currently, the Owens Valley Solar Array operating in the range 1-18 GHz and the Nobeyama Radio Heliograph at 17 and 34 GHz are the only solar dedicated radio telescopes. Using these telescopes at multiple wavelengths it is now possible to explore three dimensional structure of sunspot associated radio sources and therefore of coronal magnetic fields. We shall present these measurements at wavelengths ranging from 1.7 cm to 90 cm and associated theoretical developments.

Mcm2–7 is recruited to eukaryotic origins of DNA replication by origin recognition complex, Cdc6 and Cdt1 thereby licensing the origins. Cdc6 is essential for origin licensing during DNA replication and is readily destabilized from chromatin after Mcm2–7 loading. Here, we show that after origin licensing, deregulation of Cdc6 suppresses DNA replication in Xenopus egg extracts without the involvement of ATM/ATR-dependent checkpoint pathways. DNA replication is arrested specifically after chromatin binding of Cdc7, but before Cdk2-dependent pathways and deregulating Cdc6 after this step does not impair activation of origin firing or elongation. Detailed analyses revealed that Cdc6 deregulation leads to strong suppression of Cdc7-mediated hyperphosphorylation of Mcm4 and subsequent chromatin loading of Cdc45, Sld5 and DNA polymerase α. Mcm2 phosphorylation is also repressed although to a lesser extent. Remarkably, Cdc6 itself does not directly inhibit Cdc7 kinase activity towards Mcm2–4–6–7 in purified systems, rather modulates Mcm2–7 phosphorylation on chromatin context. Taken together, we propose that Cdc6 on chromatin acts as a modulator of Cdc7-mediated phosphorylation of Mcm2–7, and thus destabilization of Cdc6 from chromatin after licensing is a key event ensuring proper transition to the initiation of DNA replication.

We have studied the occupied and unoccupied electron states of the Pr 1 - x Ca x MnO 3 ( x = 0.2 , 0.33 and 0.4) near the Fermi level across their ferromagnetic–antiferromagnetic phase boundary using ultraviolet photoemission spectroscopy and inverse photoemission spectroscopy. The photoemission data show that the pseudogap formation in these compounds occur over an energy scale of 0.48 ± 0.02 eV . From a combined analysis of the photoemission and inverse photoemission results, we have estimated the charge transfer energy in these compounds to be ∼ 2.8 ± 0.2 eV . The results have been explained on the basis of the theoretical models that describe the electronic phase separation.

A preliminary checklist of Tamaricaceae in the Indian subcontinent has been prepared on the basis of primary observations of different taxa belonging to this family in wild habitats and on secondary observations based on examining herbarium specimens and taxonomic literature. On the Indian subcontinent (comprising Bangladesh, Bhutan, Myanmar, Nepal, Pakistan, Sri Lanka and India), the family Tamaricaceae is poorly represented (20% of all species). The present paper deals with a brief review of distribution, endemism, possible fossil ancestry, economic potential and survival threat on existing taxa, etc. The present status of endemism of Tamaricaceae in Indian subcontinent (22.5% in 2002–2007) has been compared to the data of previous investigations (50% in 1939–1940) done in nineteenth century. The decreasing rate of endemism either indicates decreasing number of endemic taxa or increasing span of distribution of pan-endemic taxa belonging to this family. For better understanding of the functional aspects...

Although initiation of DNA replication is considered to be highly coordinated through multiple protein–DNA and protein–protein interactions, it is poorly understood how particular locations within the eukaryotic chromosome are selected as origins of DNA replication. Here, we discuss recent reports that present structural information on the interaction characteristics of the archaeal orthologues of the eukaryotic origin recognition complex with their cognate binding sequences.1,2 Since the archaeal replication system is postulated as a simplified version of the one in eukaryotes, by analogy, these works provide insights into the functions of the eukaryotic initiator proteins. BioEssays 30:208–211, 2008. © 2008 Wiley Periodicals, Inc.

Observations of a solar flare at 617 MHz with the Giant Meter-wave Radio Telescope (GMRT) are used to study the morphology of flare radio emission at decimetric wavelengths. There has been very little imaging in the 500 – 1000 MHz frequency range, but it is of great interest, since it corresponds to densities at which energy is believed to be released in solar flares. This event has a very distinctive morphology at 617 MHz: the radio emission is clearly resolved by the 30″ beam into arc-shaped sources seeming to lie at the tops of long loops, anchored at one end in the active region in which the flare occurs, with the other end lying some 200 000 km away in a region of quiet solar atmosphere. Microwave images show fairly conventional behaviour for the flare in the active region: it consists of two compact sources overlying regions of opposite magnetic polarity in the photosphere. The decimetric emission is confined to the period leading up to the impulsive phase of the flare, and does not extend over a wide frequency range. This fact suggests a flare mechanism in which the magnetic field at considerable height in the corona is destabilized a few minutes prior to the main energy release lower in the corona. The radio morphology also suggests that the radiating electrons are trapped near the tops of magnetic loops, and therefore may have pitch angles near 90˚.

We describe a flare of GOES class M5.7 that was observed simultaneously by RHESSI (Ramaty High Energy Solar Spectroscopic Imager) and NoRH (Nobeyama Radio Heliograph). The flare occurred in AR 9866 located near the disk center. The hard X-ray (HXR), microwave, EIT, and TRACE 195 A observations indicate that the flaring region consisted of a complex of multiple loops. In the microwave domain the source morphology, the timing, the polarization characteristics, and the photospheric magnetic fields clearly indicate that it is of a class characterized as a "double loop" configuration, meaning two systems of magnetic flux, each consisting of many smaller loops. The observations suggest the existence of a small loop system created by the emergence of new flux, which interacts with an old flux system, and of a remote flare site that is observed primarily in radio. The former is the main flare site where we observe microwave, HXR, and EUV emissions. In HXR there are two main identifiable loop systems. The first is an elongated one filled with energetic electrons primarily emitting lower energy (12-25 keV) HXR with a colocated microwave source; this source has distinct footpoints at higher X-ray energies. The second loop system is implied by compact HXR sources in opposite magnetic polarities separated by a distance greater than the length of the first loop system. Spectroscopic analysis of the RHESSI data shows that the spectrum can be fitted with a thick-target model with a thermal component and a broken power-law component of the electron energy distribution. This model is used to address the thermal/nonthermal and radio/HXR electron number problems.

Aims. We present a summary of the analysis of thirty microflares, observed simultaneously by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) in hard X-rays and by Nobeyama RadioHeliograph (NoRH) in microwaves (17 GHz). Methods. We used microflares observed by RHESSI in the energy range 3-25 keV, and for larger events, up to 35 keV. The observations were made 2002, May 2-6. Results. We describe the imaging characteristics of these microflares including their locations in hard X-rays and microwaves and the relative positions of the micro-flaring sources. We discuss the brightness temperatures, emission measures and their hard X-ray spectral properties. We see small (mini) flaring loops clearly in NoRH and RHESSI images. The microwave emission often seems to come from the RHESSI foot points (for higher energies), and from the entire small (mini) flaring loop (for lower energies). Sometimes the two (microwave and hard X-ray) sources coincide, at other times they are at opposite ends of a mini flaring loop. Typically, the hard X-ray spectrum of the microwave associated RHESSI microflares can be fit by an isothermal component at low energies (below 10 or 12 keV) and a nonthermal component at higher energies (above 12 keV). Conclusions. Microflares in hard X-rays and in microwaves behave like normal flares in many respects. They can have both thermal and nonthermal components appearing in bremsstrahlung and gyrosynchrotron radiation.

We consider manifestations of accelerated electrons in microwave and hard X-ray emissions from solar flares. To meet our objectives, we discuss two events — those of 1999 March 16 and February 16. The first event is a short-duration burst, while the second is a long-duration event. An analysis of the first event leads to the conclusion that: 1) a seemingly single-loop configuration can actually be a double-loop one, and 2) it is possible that the pitch-angle distribution of the radio-emitting electrons can be anisotropic with practically no non-zero pitch angles. The second event shows seemingly intersecting flaring loops, and the formation of a post-eruptive arcade that can proceed as a series of double-loop interactions. From these and other published results, we conclude that: 1) doubleloop configurations can be responsible for flares showing diverse morphologies and time profiles; 2) the pitch-angle distribution of accelerated electrons can be strongly anisotropic, with an excess of small angles, contributing to a rather narrow energy range of the microwave-emitting electrons.

The members of the family Theaceae are distributed in tropical and subtropical regions, in America and Asia, a few in Africa. In Indian subcontinent (comprising of Bangladesh, Bhutan, Myanmar, Nepal, Pakistan, Sri Lanka and India), it is well-represented (50% of the total taxa). The present paper deals with distribution, phytoendemism, possible fossil ancestry, potential survival threat on existing taxa etc. of Theaceae in Indian subcontinent.

International audience; We present an analysis of five microflares, three observed simultaneously by RHESSI in hard X-rays and Nobeyama RadioHeliograph (NoRH) in microwaves (17 GHz) and two observed by RHESSI and Nancay RadioHeliograph (NRH) at metric wavelengths (150-450 MHz). Since we have no radio imaging telescopes simultaneously operating at microwave and meter wavelengths in the same time zone, we are obliged to use a different set of metric events in contrast to that used for comparison with the two radio wavelengths. We are interested in using the locations and other imaging characteristics of the events from both RHESSI and radio observations instead of just temporal correlation. So we have used the Nancay (France) metric radioheliograph at 150-450 MHz for this purpose. Here we describe the properties of five events - three in microwaves and two at metric wavelengths. We discuss the brightness temperatures, emission measures and the hard X-ray spectral properties of these microevents. One sees small (mini) flaring loops clearly in NoRH and RHESSI images. The microwave emission often seems to come from the RHESSI foot points (for higher energies), and from the entire small (mini) flaring loop (for lower energies).The RHESSI microflares seem to be associated in position with metric type III bursts. Frequently, the hard X-ray spectrum of the microwave associated RHESSI microflares can be fit by a thermal component at low energies (˜3-12 keV) and a nonthermal component at higher energies (˜12-20 keV).

We describe two flares of GOES class M5.7 and 1.5 which were observed simultaneously by RHESSI (Ramaty High Energy Solar Spectroscopic Imager) and NoRH (Nobeyama Radio Heliograph). Both flares exhibit slow motions suggestive of changing magnetic shear, loop expansion, or gradual reconnection. One flare is clearly a coronal hard X-ray and microwave flare.

We present the long term variation of solar corona based on SOHO/EIT observations from 1996 to 2004. EIT provides diagnostics of bulk corona in three channels with overlapping temperature range from 0.5 MK to 2.7 MK and with high spatial resolution. We find that the coronal emission measure increases by a factor of 4 from $2.0\times10^{27}$ cm $^{-5}$ at the solar minimum to $8.0\times10^{27}$ cm $^{-5}$ at the solar maximum. In the meantime, the overall temperature of the corona increases from 1.3 MK to 1.7 MK To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We discuss a filament eruption/coronal mass ejection (CME) event associated with a flare of GOES class M2.8 that occurred on 2001 November 17. This event was observed by the Nobeyama Radio Heliograph (NoRH) at 17 and 34 GHz. NoRH observed the filament during its eruption both as a dark feature against the solar disk and a bright feature above the solar limb. The high cadence of the radio data allows us to follow the motion of the filament at high time resolution to a height of more than half a solar radius. The filament eruption shows a very gradual onset and then a rapid acceleration phase coincident with the launch of a fast halo CME. Soft X-ray and extreme-ultraviolet (EUV) images show heating in a long loop underneath the filament prior to the flare. The NoRH height-time plot of the filament shows a roughly constant gradual acceleration for 1 hr, followed by a very abrupt acceleration coincident with the impulsive phase of the associated flare, and then a phase of constant velocity or much slower acceleration. This pattern is identical to that recently found to occur in the motion of flare-associated CMEs, which also show a sharp acceleration phase closely tied to the impulsive phase of the flare. When the rapid acceleration occurs in this event, the flare site and the filament are separated by ~0.5 R☉, making it unlikely that a disturbance propagates from one location to the other. Models in which a disruption of the large-scale coronal magnetic field simultaneously permits the acceleration of the filament and the flare energy release seem to be a better explanation for this event.