Paradigma Politik Nahdlatul Ulama (NU) dalam Bernegara

NU selalu terlihat politis. Latar sejarahnya sendiri sebagai gejala politis, minimal, dalam perspektif politik Islam, baik di level nasional maupun Internasional. Spirit lahirnya sebagai jam'iyyah berbasis simbol dan kekuatan ulama (kiai), senantiasa mengundang banyak tanya dan keterkaguman. Ibarat pedang, NU memiliki dua mata yang jernih dan tajam serta sangat berbahaya kalau dibiarkan menusuk sesuatu, termasuk menyangkut perpolitikan tanah air. Paradigma politik NU serba unik, cair, tapi menggetarkan

Do Overconfident Investors Trade Excessively in the Capital Market? Evidences in an Experimental Research Setting

The existence of overconfident investors in capital markets has been the subject of much researches in the past. Using the market data, these previous researches demonstrates that overconfident investors tend to trade excessively, leading to losses. The current experimental research addresses these issues in the Indonesia Capital Market. According to its methodology, participants are classified into three groups based on their score of overconfidence: moderate, more overconfident, and less overconfident investors. The research design employs the state of no available market information, good news signals, and bad news signals as treatments. The result demonstrates that the more overconfident investors perform higher trading value than those who are less overconfident in all artificialmarkets leading to transaction losses, except that in the bad news market. In that bad news market, the more and the less overconfident investors gain profits, and the moderateinvestors suffer from trading losses

Influence of femoral component design on proximal femoral bone mass after total hip replacement : a randomized controlled trial

Background: In this randomized controlled trial (RCT), we compared bone remodeling and bone turnover between 2 total hip arthroplasty implants—the short, proximally porous-coated Tri-Lock Bone-Preservation Stem and a conventional, fully-coated Corail prosthesis—over a 2-year postoperative period. Methods: Forty-six participants received the Tri-Lock prosthesis and 40 received the Corail prosthesis. At baseline, the 2 groups had similar demographics, proximal femoral bone mineral density (BMD), bone turnover markers, radiographic canal flare index, and patient-reported outcome measure (PROM) scores. Outcomes were measured at weeks 26, 52, and 104. Results: Loss of periprosthetic bone, measured by high-sensitivity dual x-ray absorptiometry region-free analysis (DXA-RFA), was identified at the calcar and proximal-lateral aspect of the femur in both prosthesis groups (p 0.05). The adverse-event rate was also similar between the groups (p > 0.05). Conclusions: This RCT shows that prostheses intended to preserve proximal femoral bone do not necessarily perform better in this regard than conventional cementless designs. DXA-RFA is a sensitive tool for detecting spatially complex patterns of periprosthetic bone remodeling. Level of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence

A low frequency sub-arcsecond view of powerful radio galaxies in rich-cluster environments: 3C 34 and 3C 320

Models of radio galaxy physics have been primarily based on high frequency ($\geqslant$1 GHz) observations of their jets, hotspots, and lobes. Without highly resolved low frequency observations, which provide information on older plasma, our understanding of the dynamics of radio galaxies and their interaction with their environment is limited. Here, we present the first sub-arcsecond (0.3") resolution images at 144 MHz of two powerful radio galaxies situated in rich cluster environments, namely 3C 34 and 3C 320, using the International Low Frequency Array Telescope. We detect for the first time at low frequencies a plethora of structures in these objects, including strikingly large filaments across the base of the lobes in both sources, which are spatially associated with dense regions in the ambient medium. For 3C 34 we report a spectral flattening in the region of the central filament, suggesting that the origin of the filaments is related to the presence of large-scale ordered magnetic fields. We also report periodic total intensity and spectral index banding of diffuse emission in the eastern lobe, seen for the first time in radio galaxy lobes. The hotspot complexes are resolved into multiple fragments of varying structure and spectral index; we discuss the implications for particle acceleration and jet termination models. We find at most smooth gradients in the spectral behaviour of the hotspot structure suggesting that particle acceleration, if present, may be occurring throughout the complex, in contrast to simple models, but different jet termination models may apply to both sources.Comment: 16 pages, 7 figures, 2 tables. Accepted for publication in Monthly Notices of the Royal Astronomical Society, 2023 February 0

Multi-frequency characterisation of remnant radio galaxies in the Lockman Hole field

Context. Remnant radio galaxies represent an important phase in the life-cycle of radio active galactic nuclei. It is suggested that in this phase, the jets have switched off and the extended emission is fading rapidly. This phase is not well-studied due to the lack of statistical samples observed at both low and high frequencies. Aims. In this work, we study a sample of 23 candidate remnant radio galaxies previously selected using the Low Frequency Array at 150 MHz in the Lockman Hole field. We examine their morphologies and study their spectral properties to confirm their remnant nature and revise the morphological and spectral criteria used to define the initial sample. Methods. We present new observations with the Karl G. Jansky Very Large Array at 6000 MHz at both high and low resolution. These observations allowed us to observe the presence or absence of cores and study the spectral curvature and steepness of the spectra of the total emission expected at these high frequencies for the remnant candidates. Results. We confirm 13 out of 23 candidates as remnant radio sources. This corresponds to 7% of the full sample of active, restarted, and remnant candidates from the Lockman Hole field. Surprisingly, only a minority of remnants reside in a cluster (23%). The remnant radio galaxies show a range of properties and morphologies. The majority do not show detection of the core at 6000 MHz and their extended emission often shows ultra-steep spectra (USS). However, there are also remnants with USS total emission and a detection of the core at 6000 MHz, possibly indicating a variety of evolutionary stages in the remnant phase. We confirm the importance of the combination of morphological and spectral criteria and this needs to be taken into consideration when selecting a sample of remnant radio sources

Radio spectral properties and jet duty cycle in the restarted radio galaxy 3C388

© ESO 2020. The original publication is available at https://doi.org/10.1051/0004-6361/202037457.Context. Restarted radio galaxies represent a unique tool for investigating the duty cycle of the jet activity in active galactic nuclei (AGN). The radio galaxy 3C388 has long been claimed to be a peculiar example of an AGN with multi-epoch activity because it shows a very sharp discontinuity in the GHz spectral index distribution of its lobes. Aims. We present here for the first time a spatially resolved study of the radio spectrum of 3C388 down to MHz frequencies aimed at investigating the radiative age of the source and constraining its duty cycle. Methods. We used new low-frequency observations at 144 MHz performed with the Low Frequency Array and at 350 MHz performed with the Very Large Array that we combined with archival data at higher frequencies (614, 1400, and 4850 MHz). Results. We find that the spectral indices in the lower frequency range, 144-614 MHz, have flatter values (αlow ∼0.55-1.14) than those observed in the higher frequency range, 1400-4850 MHz, (αhigh ∼0.75-1.57), but they follow the same distribution across the lobes, with a systematic steepening towards the edges. However, the spectral shape throughout the source is not uniform and often deviates from standard models. This suggests that mixing of different particle populations occurs, although it remains difficult to understand whether this is caused by observational limitations (insufficient spatial resolution and/or projection effects) or by the intrinsic presence of multiple particle populations, which might be related to the two different outbursts. Conclusions. Using single-injection radiative models, we compute that the total source age is ≲ 80 Myr and that the duty cycle is about ton/ttot ∼ 60%, which is enough to prevent the intracluster medium from cooling, according to X-ray estimates. While to date the radio spectral distribution of 3C388 remains a rare case among radio galaxies, multi-frequency surveys performed with new-generation instruments will soon allow us to investigate whether more sources with the same characteristics exist.Peer reviewe

Remnant radio-loud AGN in the Herschel-ATLAS field

Only a small fraction of observed active galactic nuclei (AGN) display large-scale radio emission associated with jets, yet these radio-loud AGN have become increasingly important in models of galaxy evolution. In determining the dynamics and energetics of the radio sources over cosmic time, a key question concerns what happens when their jets switch off. The resulting ‘remnant' radio-loud AGN have been surprisingly evasive in past radio surveys, and therefore statistical information on the population of radio-loud AGN in their dying phase is limited. In this paper, with the recent developments of Low-Frequency Array (LOFAR) and the Very Large Array, we are able to provide a systematically selected sample of remnant radio-loud AGN in the Herschel-ATLAS field. Using a simple core-detection method, we constrain the upper limit on the fraction of remnants in our radio-loud AGN sample to 9 per cent, implying that the extended lobe emission fades rapidly once the core/jets turn off. We also find that our remnant sample has a wide range of spectral indices (−1.5 ⩽ α1400150 ⩽ −0.5), confirming that the lobes of some remnants may possess flat spectra at low frequencies just as active sources do. We suggest that, even with the unprecedented sensitivity of LOFAR, our sample may still only contain the youngest of the remnant population