Phase-reference VLBI Observations of the Compact Steep-Spectrum Source 3C 138

We investigate a phase-reference VLBI observation that was conducted at 15.4 GHz by fast switching VLBA antennas between the compact steep-spectrum radio source 3C 138 and the quasar PKS 0528+134 which are about 4$^\circ$ away on the sky. By comparing the phase-reference mapping with the conventional hybrid mapping, we demonstrate the feasibility of high precision astrometric measurements for sources separated by 4$^\circ$. VLBI phase-reference mapping preserves the relative phase information, and thus provides an accurate relative position between 3C 138 and PKS 0528+134 of $\Delta\alpha=-9^m46^s.531000\pm0^s.000003$ and $\Delta\delta=3^\circ6^\prime26^{\prime\prime}.90311\pm0^{\prime\prime}.00007$ (J2000.0) in right ascension and declination, respectively. This gives an improved position of the nucleus (component A) of 3C 138 in J2000.0 to be RA=$05^h 21^m 9^s.885748$ and Dec=$16^\circ 38' 22''.05261$ under the assumption that the position of calibrator PKS 0528+134 is correct. We further made a hybrid map by performing several iterations of CLEAN and self-calibration on the phase-referenced data with the phase-reference map as an input model for the first phase self-calibration. Compared with the hybrid map from the limited visibility data directly obtained from fringe fitting 3C 138 data, this map has a similar dynamic range, but a higher angular resolution. Therefore, phase-reference technique is not only a means of phase connection, but also a means of increasing phase coherence time allowing self-calibration technique to be applied to much weaker sources.Comment: 9 pages plus 2 figures, accepted by PASJ (Vol.58 No.6

Ising-type Magnetic Anisotropy in CePd2_2As2_2

We investigated the anisotropic magnetic properties of CePd$_2$As$_2$ by magnetic, thermal and electrical transport studies. X-ray diffraction confirmed the tetragonal ThCr$_2$Si$_2$-type structure and the high-quality of the single crystals. Magnetisation and magnetic susceptibility data taken along the different crystallographic directions evidence a huge crystalline electric field (CEF) induced Ising-type magneto-crystalline anisotropy with a large $c$-axis moment and a small in-plane moment at low temperature. A detailed CEF analysis based on the magnetic susceptibility data indicates an almost pure $\langle\pm5/2 \rvert$ CEF ground-state doublet with the dominantly $\langle\pm3/2 \rvert$ and the $\langle\pm1/2 \rvert$ doublets at 290 K and 330 K, respectively. At low temperature, we observe a uniaxial antiferromagnetic (AFM) transition at $T_N=14.7$ K with the crystallographic $c$-direction being the magnetic easy-axis. The magnetic entropy gain up to $T_N$ reaches almost $R\ln2$ indicating localised $4f$-electron magnetism without significant Kondo-type interactions. Below $T_N$, the application of a magnetic field along the $c$-axis induces a metamagnetic transition from the AFM to a field-polarised phase at $\mu_0H_{c0}=0.95$ T, exhibiting a text-book example of a spin-flip transition as anticipated for an Ising-type AFM.Comment: 9 Pages, 8 figure

Impact of Empowerment Theory-Based Nursing Intervention on the Quality of Life and Negative Emotions of Patients Diagnosed with Brain Metastasis Post Breast Cancer Surgery

Rongge Jiang,1 Haibai Liu,2 Xue Jiang,2 Ding Wang,2 Xiaoyu Li,2 Yi Shang3 1Neurosurgery Department 1, Baoding No.1 Central Hospital, Baoding, 071000, People’s Republic of China; 2Department of Nursing, Shijiazhuang Medical College, Shijiazhuang, 050599, People’s Republic of China; 3Department of Mammary, Shijiazhuang Fourth Hospital, Shijiazhuang, 050000, People’s Republic of ChinaCorrespondence: Xiaoyu Li, Shijiazhuang Medical College, No. 1 Tongxin Road, Lingshou County, Shijiazhuang, Hebei, 050599, People’s Republic of China, Tel + 8613603117321, Email [email protected]: This study explores the impact of a nursing intervention grounded in empowerment theory, focusing on behavioral change, on brain metastasis patients post-breast cancer surgery.Methods: Between June 2021 and June 2023, 102 patients diagnosed with brain metastasis after breast cancer surgery at Bao Ding No.1 Central Hospital were randomized into two groups. The control group (51 patients) received standard nursing care, while the observation group (51 patients) participated in a behavioral change nursing intervention influenced by empowerment theory. The evaluation metrics included measures of negative emotions, compliance with treatment protocols, overall quality of life, and nursing satisfaction, assessed at multiple time points during the study period.Results: The intervention led to significant reductions in negative emotions for all patients when compared to their pre-intervention statuses, with the observation group exhibiting notably lower depression and anxiety scores at one and three months post-intervention (P < 0.05). Additionally, this group achieved higher compliance scores and demonstrated greater improvements in quality of life than the control group (P < 0.05). Nursing satisfaction was also significantly higher in the observation group, with 96.08% reporting high satisfaction compared to 80.39% in the control group (P < 0.05).Conclusion: Implementing a nursing intervention that emphasizes behavioral changes and leverages empowerment theory significantly enhances the quality of life, reduces negative emotions, boosts compliance with treatment, and increases nursing satisfaction among patients with brain metastasis following breast cancer surgery. This suggests that such interventions could be a valuable component of postoperative care for this patient population.Keywords: behavioral change, empowerment theory, negative emotions, nursing intervention, brain metastasis, breast cancer, quality of lif

Low threshold lasing emissions from a single upconversion nanocrystal.

Cross-relaxation among neighboring emitters normally causes self-quenching and limits the brightness of luminescence. However, in nanomaterials, cross-relaxation could be well-controlled and employed for increasing the luminescence efficiency at specific wavelengths. Here we report that cross-relaxation can modulate both the brightness of single upconversion nanoparticles and the threshold to reach population inversion, and both are critical factors in producing the ultra-low threshold lasing emissions in a micro cavity laser. By homogenously coating a 5-μm cavity with a single layer of nanoparticles, we demonstrate that doping Tm3+ ions at 2% can facilitate the electron accumulation at the intermediate state of 3H4 level and efficiently decrease the lasing threshold by more than one order of magnitude. As a result, we demonstrate up-converted lasing emissions with an ultralow threshold of continuous-wave excitation of ~150 W/cm2 achieved at room temperature. A single nanoparticle can lase with a full width at half-maximum as narrow as ~0.45 nm

The First Release of the CSTAR Point Source Catalog from Dome A, Antarctica

In 2008 January the 24th Chinese expedition team successfully deployed the Chinese Small Telescope ARray (CSTAR) to DomeA, the highest point on the Antarctic plateau. CSTAR consists of four 14.5cm optical telescopes, each with a different filter (g, r, i and open) and has a 4.5degree x 4.5degree field of view (FOV). It operates robotically as part of the Plateau Observatory, PLATO, with each telescope taking an image every 30 seconds throughout the year whenever it is dark. During 2008, CSTAR #1 performed almost flawlessly, acquiring more than 0.3 million i-band images for a total integration time of 1728 hours during 158 days of observations. For each image taken under good sky conditions, more than 10,000 sources down to 16 mag could be detected. We performed aperture photometry on all the sources in the field to create the catalog described herein. Since CSTAR has a fixed pointing centered on the South Celestial Pole (Dec =-90 degree), all the sources within the FOV of CSTAR were monitored continuously for several months. The photometric catalog can be used for studying any variability in these sources, and for the discovery of transient sources such as supernovae, gamma-ray bursts and minor planets.Comment: 1 latex file and 9 figures The paper is accepted by PAS

The Center of Activity in the CSS Superluminal Source 3C 138

We present the results from the first quasi-simultaneous multi-frequency (2.3, 5.0, 8.4 and 15 GHz) Very Long Baseline Interferometry (VLBI) observations of a compact steep spectrum (CSS) superluminal source 3C138. For the first time, the spectral distribution of the components within its central 10 milli-arcsecond (mas) region was obtained. This enables us to identify the component at the western end as the location of the nuclear activity on the assumption that the central engine is associated with one of the detected components. The possibility that none of these visible components is the true core is also discussed. The new measurements further clarify the superluminal motions of its inner jet components. The multi-frequency data reveal a convex spectrum in one jet component, inferring the existence of free-free absorption by the ambient dense plasma.Comment: 14 pages, 4 figures, accepted by Ap

The sky brightness and transparency in i-band at Dome A, Antarctica

The i-band observing conditions at Dome A on the Antarctic plateau have been investigated using data acquired during 2008 with the Chinese Small Telescope ARray. The sky brightness, variations in atmospheric transparency, cloud cover, and the presence of aurorae are obtained from these images. The median sky brightness of moonless clear nights is 20.5 mag arcsec^{-2} in the SDSS $i$ band at the South Celestial Pole (which includes a contribution of about 0.06 mag from diffuse Galactic light). The median over all Moon phases in the Antarctic winter is about 19.8 mag arcsec^{-2}. There were no thick clouds in 2008. We model contributions of the Sun and the Moon to the sky background to obtain the relationship between the sky brightness and transparency. Aurorae are identified by comparing the observed sky brightness to the sky brightness expected from this model. About 2% of the images are affected by relatively strong aurorae.Comment: There are 1 Latex file and 14 figures accepted by A

High-Redshift SDSS Quasars with Weak Emission Lines

We identify a sample of 74 high-redshift quasars (z>3) with weak emission lines from the Fifth Data Release of the Sloan Digital Sky Survey and present infrared, optical, and radio observations of a subsample of four objects at z>4. These weak emission-line quasars (WLQs) constitute a prominent tail of the Lya+NV equivalent width distribution, and we compare them to quasars with more typical emission-line properties and to low-redshift active galactic nuclei with weak/absent emission lines, namely BL Lac objects. We find that WLQs exhibit hot (T~1000 K) thermal dust emission and have rest-frame 0.1-5 micron spectral energy distributions that are quite similar to those of normal quasars. The variability, polarization, and radio properties of WLQs are also different from those of BL Lacs, making continuum boosting by a relativistic jet an unlikely physical interpretation. The most probable scenario for WLQs involves broad-line region properties that are physically distinct from those of normal quasars.Comment: Updated to match version published in ApJ. 20 pages, 12 figure

The PLATO Dome A Site-Testing Observatory : instrumentation and first results

The PLATeau Observatory (PLATO) is an automated self-powered astrophysical observatory that was deployed to Dome A, the highest point on the Antarctic plateau, in 2008 January. PLATO consists of a suite of site-testing instruments designed to quantify the benefits of the Dome A site for astronomy, and science instruments designed to take advantage of the unique observing conditions. Instruments include CSTAR, an array of optical telescopes for transient astronomy; Gattini, an instrument to measure the optical sky brightness and cloud cover statistics; DASLE, an experiment to measure the statistics of the meteorological conditions within the near-surface layer; Pre-HEAT, a submillimeter tipping radiometer measuring the atmospheric transmission and water vapor content and performing spectral line imaging of the Galactic plane; and Snodar, an acoustic radar designed to measure turbulence within the near-surface layer. PLATO has run completely unattended and collected data throughout the winter 2008 season. Here we present a detailed description of the PLATO instrument suite and preliminary results obtained from the first season of operation

Impact of antimalarial (AM) on serum lipids in systemic lupus erythematosus (SLE) patients

Background: Dyslipidemia is a common disorder in systemic lupus erythematosus (SLE) patients. It is still inconclusive whether antimalarial drugs could affect the serum lipids in SLE patients, therefore we conducted a systematic review and meta-analysis of available data to address this issue. Methods: We comprehensively searched the databases of PubMed, EMBASE and Cochrane Library from date of inception to Sep 2018 for both randomized controlled trials (RCTs) and observational studies. Review Manager 5.3 software was used for analysis. We performed meta-analysis using random-effects model and weighted the mean difference (WMD) and its 95% confidence interval (CI). The Q test was used to assess the presence of heterogeneity and the I 2 index was used to quantify the extent of heterogeneity. Results: In total, 8 studies met our selection criteria including 2 RCTs, 2 cohort studies, and 4 case-control studies. There were 717 patients (336 patients in CQ (chloroquine) or HCQ (hydroxychloroquine) group, and 381 patients in control group (SLE patients without the therapy of AM)). Compared with the control group, TC, TG, LDL-C, VLDL-C were associated with a significant decrease, respectively (WMD = −21.40 mg/dL, 95% CI −27.62 to −15.18, P < .00001), (WMD = −29.07 mg/dL, 95% CI −45.28 to −12.86, P = .0004), (WMD = −16.25 mg/dL, 95% CI −28.82 to −3.68, P = .01), (WMD = −6.41 mg/dL, 95% CI −12.39 to 0.44, P = .04), however the change of HDL-C did not reach statistically significance (WMD = 4.42 mg/dL, 95% CI −1.21 to 10.06, P = .12). Conclusions: CQ or HCQ can infect the serum lipids in SLE patients. However, these results should be interpreted with cautions since lacking sufficient RCTs