764 research outputs found
Integral and Rxte/Asm Observations on Igr J17098-3628
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 20 keV, IBIS/ISGRI caught an outburst in
March 2005, lasting for 5 days with detection significance of 73
(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 2 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
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
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
We report on an analysis of X- and -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 significance
detection in the 20-100 keV band, while the COMPTEL 6-years data provide a
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 -rays, the source shows
persistent emission over years. The hard X-ray spectrum is well represented by
a power-law model, with in the 20-250 keV band. This photon
index is well consistent with the previous report of obtained
at 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 to at a break energy keV. At MeV energies, the
spectrum softens to . These results, together with the EGRET
measurement at MeV, constitute a broad-band spectrum containing the
peak of the power output at MeV energies, similar to most high-luminosity
-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
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
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
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.
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
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