767 research outputs found

    Integral and Rxte/Asm Observations on Igr J17098-3628

    Full text link
    To probe further the possible nature of the unidentified source IGR J17098-3628, we have carried out a detailed analysis of its long-term time variability as monitored by RXTE/ASM, and of its hard X-ray properties as observed by INTEGRAL. INTEGRAL has monitored this sky region over years and significantly detected IGR J17098-3628 only when the source was in this dubbed active state. In particular, at \ge 20 keV, IBIS/ISGRI caught an outburst in March 2005, lasting for \sim5 days with detection significance of 73σ\sigma (20-40 keV) and with the emission at << 200 keV. The ASM observations reveal that the soft X-ray lightcurve shows a similar outburst to that detected by INTEGRAL, however the peak of the soft X-ray lightcurve either lags, or is preceded by, the hard X-ray (>>20 keV) outburst by \sim2 days. This resembles the behavior of X-ray novae like XN 1124-683, hence it further suggests a LMXB nature for IGR J17098-3628. While the quality of the ASM data prevents us from drawing any definite conclusions, these discoveries are important clues that, coupled with future observations, will help to resolve the as yet unknown nature of IGR J17098-3628.Comment: 15 pages, 7 figure, accepted in PAS

    Recovery of histidine-tagged nucleocapsid protein of Newcastle disease virus using immobilised metal affinity chromatography

    Get PDF
    An immobilised metal affinity packed bed adsorption chromatography (IMA-PBAC) for the purification of recombinant nucleocapsid protein (NP) of Newcastle disease virus (NDV) directly from clarified feedstock was developed. The XK 16/20 (i.d. = 16 mm) was used as a packed bed column and Streamline chelating adsorbent immobilised with Ni2+ ion was used as IMA adsorbent. This purification method has resulted in a 59% adsorption and 5.6% recovery of NP protein. Adsorbed NP proteins were successfully recovered using a two-step elution protocol which employed elution buffer 1 containing 50 mM imidazole to eliminate contaminating proteins and elution buffer 2 containing 350 mM imidazole to recover the NP protein at pH 8 with flow velocity of 10 cm h−1. About 70% of the adsorbed NP protein was eluted. The purity of the recovered NP protein was about 70% and the volume of processing fluid was reduced by a factor of 4. The antigenic features of purified NP proteins were confirmed by enzyme-linked immunosorbent assay (ELISA) analysis

    Purification of recombinant nucleocapsid protein of Newcastle disease virus from unclarified feedstock using expanded bed adsorption chromatography

    Get PDF
    In the present work, a single-step purification of recombinant nucleocapsid protein (NP) of the Newcastle disease virus (NDV) directly from unclarified feedstock using an expanded bed adsorption chromatography (EBAC) was developed. Streamline 25 column (ID = 25 mm) was used as a contactor and Streamline chelating adsorbent immobilized with Ni2+ ion was used as affinity adsorbent. The dynamic binding capacity of Ni2+-loaded Streamline chelating adsorbent for the NP protein in unclarified feedstock was found to be 2.94 mg ml−1 adsorbent at a superficial velocity of 200 cm h−1. The direct purification of NP protein from unclarified feedstock using expanded bed adsorption has resulted in a 31% adsorption and 9.6% recovery of NP protein. The purity of the NP protein recovered was about 70% and the volume of processing fluid was reduced by a factor of 10. The results of the present study show that the IMA-EBAC developed could be used to combine the clarification, concentration and initial purification steps into a single-step operation

    High energy properties of PKS 1830-211

    Full text link
    We report on an analysis of X- and γ\gamma-ray observations of PKS 1830-211, based on the long-term campaigns carried out by \emph{INTEGRAL} and COMPTEL. The \emph{INTEGRAL} data currently available present a 33σ33\sigma significance detection in the 20-100 keV band, while the COMPTEL 6-years data provide a 5.2σ5.2\sigma significance detection in the 1-3 MeV energy band. At hard X-rays, \emph{INTEGRAL} and supplementary \emph{SWIFT} observations show flux variability on timescales of months. At γ\gamma-rays, the source shows persistent emission over years. The hard X-ray spectrum is well represented by a power-law model, with Γ1.3\Gamma \sim 1.3 in the 20-250 keV band. This photon index is well consistent with the previous report of Γ1.3\Gamma \sim 1.3 obtained at E>3.5E > 3.5 keV from the best fit of \emph{XMM-Newton} data with a broken power law model. The joint \emph{XMM-Newton}/\emph{INTEGRAL} spectrum presented here is then fit with a broken power-law model and the parameters are refined compared to the previous. The results show the photon index changes from 1.0\sim 1.0 to 1.3\sim 1.3 at a break energy 4\sim 4 keV. At MeV energies, the spectrum softens to Γ2.2\Gamma \sim 2.2. These results, together with the EGRET measurement at E100E \ge 100 MeV, constitute a broad-band spectrum containing the peak of the power output at MeV energies, similar to most high-luminosity γ\gamma-ray blazars. The measured spectral characterstics are then discussed in the framework of the gravitational lens effects.Comment: accepted for Ap

    MiniZero: Comparative Analysis of AlphaZero and MuZero on Go, Othello, and Atari Games

    Full text link
    This paper presents MiniZero, a zero-knowledge learning framework that supports four state-of-the-art algorithms, including AlphaZero, MuZero, Gumbel AlphaZero, and Gumbel MuZero. While these algorithms have demonstrated super-human performance in many games, it remains unclear which among them is most suitable or efficient for specific tasks. Through MiniZero, we systematically evaluate the performance of each algorithm in two board games, 9x9 Go and 8x8 Othello, as well as 57 Atari games. For two board games, using more simulations generally results in higher performance. However, the choice of AlphaZero and MuZero may differ based on game properties. For Atari games, both MuZero and Gumbel MuZero are worth considering. Since each game has unique characteristics, different algorithms and simulations yield varying results. In addition, we introduce an approach, called progressive simulation, which progressively increases the simulation budget during training to allocate computation more efficiently. Our empirical results demonstrate that progressive simulation achieves significantly superior performance in two board games. By making our framework and trained models publicly available, this paper contributes a benchmark for future research on zero-knowledge learning algorithms, assisting researchers in algorithm selection and comparison against these zero-knowledge learning baselines. Our code and data are available at https://rlg.iis.sinica.edu.tw/papers/minizero.Comment: Submitted to IEEE Transactions on Games, under revie

    2-[(1,3-Benzothia­zol-2-yl)imino­meth­yl]-4-bromo­phenol

    Get PDF
    In the title compound, C14H9BrN2OS, the dihedral angle between the benzene rings is 3.1 (3)°. An intra­molecular O—H⋯N(imine) hydrogen bond occurs. The crystal structure is stabilized by weak inter­molecular C—H⋯O inter­actions

    Efficacy of multidomain interventions to improve physical frailty, depression and cognition: data from cluster- randomized controlled trials

    Full text link
    BackgroundFrailty is the pre- eminent exigency of aging. Although frailty- related impairments are preventable, and multidomain interventions appear more effective than unimodal ones, the optimal components remain uncertain.MethodsWe devised multidomain interventions against physical and cognitive decline among prefrail/frail community- dwelling - ¥65- year- olds and evaluated these in complementary cluster- randomized trials of efficacy and participant empowerment. The Efficacy Study compared ~3- monthly telephone consultations vs. 16, 2 h sessions/year comprising communally partaken physical and cognitive training plus nutrition and disease education; the Empowerment Study compared the standard Efficacy Study multidomain intervention (Sessions 1- 10) vs. an enhanced version redesigned to empower and motivate individual participants. Changes from baseline in physical, functional, and cognitive performance were measured after 6 and 12 months in the Efficacy Study and after 6 months in the Empowerment Study, with post- intervention follow- up at 9 months. Primary outcomes are as follows: Cardiovascular Health Study frailty score; gait speed; handgrip strength; and Montreal Cognitive Assessment (MoCA). Secondary outcomes are as follows: instrumental activities of daily living; metabolic equivalent of task (MET); depressed mood (Geriatric Depression Scale- 5 - ¥2); and malnutrition (Mini- Nutritional Assessment short- form - ¤11). Intervention effects were analyzed using a generalized linear mixed model.ResultsEfficacy Study participants (n = 1082, 40 clusters) were 75.1 ± 6.3 years old, 68.7% women, and 64.7% prefrail/frail; analytic clusters: 19 intervention (410/549 completed) vs. 21 control (375/533 completed). Empowerment Study participants (n = 440, 14 clusters) were 75.9 ± 7.1 years old, 83.6% women, and 56.7% prefrail/frail; analytic clusters: seven intervention (209/230 completed) vs. seven control (189/210 completed). The standard and enhanced multidomain interventions both reduced frailty and significantly improved aspects of physical, functional, and cognitive performance, especially among - ¥75- year- olds. Standard multidomain intervention decreased depression [odds ratio 0.56, 95% confidence interval (CI) 0.32, 0.99] and malnutrition (odds ratio 0.45, 95% CI 0.26, 0.78) by 12 months and improved concentration at Months 6 (0.23, 95% CI 0.04, 0.42) and 12 (0.46, 95% CI 0.22, 0.70). Participant empowerment augmented activity (4.67 MET/h, 95% CI 1.64, 7.69) and gait speed (0.06 m/s, 95% CI 0.00, 0.11) at 6 months, with sustained improvements in delayed recall (0.63, 95% CI 0.20, 1.06) and MoCA performance (1.29, 95% CI 0.54, 2.03), and less prevalent malnutrition (odds ratio 0.39, 95% CI 0.18, 0.84), 3 months after the intervention ceased.ConclusionsPragmatic multidomain intervention can diminish physical frailty, malnutrition, and depression and enhance cognitive performance among community- dwelling elders, especially - ¥75- year- olds; this might supplement healthy aging policies, probably more effectively if participants are empowered.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/1/jcsm12534.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/2/10.1002_jcsm.12534_Fig_S4.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/3/jcsm12534_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/4/10.1002_jcsm.12534_Fig_S2.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/5/10.1002_jcsm.12534_Table_S3.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/6/10.1002_jcsm.12534_Fig_S3.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/7/10.1002_jcsm.12534_Appendix_S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/8/10.1002_jcsm.12534_Table_S2.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/9/10.1002_jcsm.12534_Table_S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156002/10/10.1002_jcsm.12534_Fig_S1.pd

    Bilateral Habenula deep brain stimulation for treatment-resistant depression: clinical findings and electrophysiological features.

    Get PDF
    Deep brain stimulation (DBS) of structures in the brain's reward system is a promising therapeutic option for patients with treatment-resistant depression (TRD). Recently, DBS of the habenula (HB) in the brain's anti-reward system has also been reported to alleviate depressive symptoms in patients with TRD or bipolar disorder (BD). In this pilot open-label prospective study, we explored the safety and clinical effectiveness of HB-DBS treatment in seven patients with TRD or BD. Also, local field potentials (LFPs) were recorded from the patients' left and right HB to explore the power and asymmetry of oscillatory activities as putative biomarkers of the underlying disease state. At 1-month follow-up (FU), depression and anxiety symptoms were both reduced by 49% (n = 7) along with substantial improvements in patients' health status, functional impairment, and quality of life. Although the dropout rate was high and large variability in clinical response existed, clinical improvements were generally maintained throughout the study [56%, 46%, and 64% reduction for depression and 61%, 48%, and 70% reduction for anxiety at 3-month FU (n = 5), 6-month FU (n = 5), and 12-month FU (n = 3), respectively]. After HB-DBS surgery, sustained improvements in mania symptoms were found in two patients who presented with mild hypomania at baseline. Another patient, however, experienced an acute manic episode 2 months after surgery that required hospitalization. Additionally, weaker and more symmetrical HB LFP oscillatory activities were associated with more severe depression and anxiety symptoms at baseline, in keeping with the hypothesis that HB dysfunction contributes to MDD pathophysiology. These preliminary findings indicate that HB-DBS may offer a valuable treatment option for depressive symptoms in patients who suffer from TRD or BD. Larger and well-controlled studies are warranted to examine the safety and efficacy of HB-DBS for treatment-refractory mood disorders in a more rigorous fashion
    corecore