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Double neutron star (DNS) systems offer excellent opportunities to test gravity theories. We report the timing results of PSR J1901+0658, the first pulsar discovered in the FAST Galactic Plane Pulsar Snapshot (GPPS) Survey. Based on timing observations by FAST over 5 yr, we obtain the phase-coherent timing solution and derive the precise measurements of its position, spin parameters, orbital parameters, and dispersion measure. It has a period of 75.7 ms, a period derivative of 2.169(6) × 10−19 s s−1, and a characteristic age of 5.5 Gyr. This pulsar is in an orbit with a period of 14.45 d and an eccentricity of 0.366. One post-Keplerian parameter, periastron advance, has been well-measured as being 0.00531(9) deg yr−1, from which the total mass of this system is derived to be 2.79(7) M⊙. The pulsar has the mass upper limit of 1.68 M⊙, so the lower limit for the companion mass is 1.11 M⊙. Because PSR J1901+0658 is a partially recycled pulsar in an eccentric binary orbit with such a large companion mass, it should be in a DNS system according to the evolution history of the binary system. [ABSTRACT FROM AUTHOR]

We report five new fast radio bursts (FRBs) discovered from the Galactic Plane Pulsar Snapshot (GPPS) survey by the Five-hundred-meter Aperture Spherical radio Telescope (FAST): FRB 20210126, FRB 20210208, FRB 20210705, FRB 20211005, and FRB 20220306. To date, no repeating bursts from these FRB sources have been detected in the follow-up monitoring observations, leading to their classification as potential one-off events. We obtain the basic parameters for these bursts, including position, dispersion measure, pulse width, spectral index, scattering time-scale, etc. The fluences and flux densities are generally lower in comparison to the values observed in one-off bursts discovered by other telescopes. Among the observed bursts, polarization data for four bursts were recorded during observations. Consequently, we obtain polarization profiles and Faraday rotation measures for these bursts. [ABSTRACT FROM AUTHOR]

Timing observations are crucial for determining the basic parameters of newly discovered pulsars. Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST) with the L-band 19-beam receiver covering the frequency range of 1.0–1.5 GHz, the FAST Galactic Plane Pulsar Snapshot (GPPS) Survey has discovered more than 600 faint pulsars with flux densities of only a few or a few tens of μJy at 1.25 GHz. To obtain accurate position, spin parameters and dispersion measure of a pulsar, and to calculate derived parameters such as the characteristic age and surface magnetic field, we collect available FAST pulsar data obtained either through targeted follow-up observations or through coincidental survey observations with one of the 19 beams of the receiver. From these data we obtain time of arrival (TOA) measurements for 30 newly discovered pulsars as well as for 13 known pulsars. We demonstrate that the TOA measurements acquired by the FAST from any beams of the receiver in any observation mode (e.g. the tracking mode or the snapshot mode) can be combined to get timing solutions. We update the ephemerides of 13 previously known pulsars and obtain the first phase-coherent timing results for 30 isolated pulsars discovered in the FAST GPPS Survey. Notably, PSR J1904+0853 is an isolated millisecond pulsar, PSR J1906+0757 is a disrupted recycled pulsar, and PSR J1856+0211 has a long period of 9.89 s that can constrain pulsar death lines. Based on these timing solutions, all available FAST data have been added together to obtain the best pulse profiles for these pulsars. [ABSTRACT FROM AUTHOR]

As radio telescopes become more sensitive, radio frequency interference (RFI) is becoming more important for interesting signals of radio astronomy. There is a demand for developing an automatic, accurate and efficient RFI mitigation method. Therefore, we have investigated an RFI detection algorithm. First, we introduce an asymmetrically reweighted penalized least squares (ArPLS) method to estimate the baseline more accurately. After removing the estimated baseline, several novel strategies were proposed based on the SumThreshold algorithm for detecting different types of RFI. The threshold parameter in SumThreshold can be determined automatically and adaptively. The adaptiveness is essential for reducing human intervention and for the online RFI processing pipeline. Applications to data from the Five-hundred-meter Aperture Spherical Telescope (FAST) show that the proposed scheme based on ArPLS and SumThreshold is superior to some typically available methods for RFI detection with respect to efficiency and performance. [ABSTRACT FROM AUTHOR]

Purpose: To review the published data describing the incidence, etiology, management, and outcomes of flank hernia.Methods: A retrospective review of articles identified with an online search (using the terms "flank hernia", "flank bulge", "lateral hernia", "retroperitoneal aorta hernia", and "open radical nephrectomy") was performed. Studies exclusively on lumbar hernia or subcostal hernia were excluded.Results: All articles retained for analysis (N = 26) were uncontrolled series or case reports; there were no controlled trials. The incidence of incisional hernia in the flank was ~ 17% (total patients analyzed = 1,061). Flank hernia repair was accomplished successfully with a variety of techniques, with overall mean rates of perioperative complications, chronic post-procedure pain, and recurrence equal to 20, 11, and 7%, respectively. Mesh utilization was universal.Conclusions: The available data of outcomes of flank hernia repair are not of high quality, and recommendations essentially consist of expert opinions. Operative approach (open vs. laparoscopic) and mesh insertion details have varied, but reasonable results appear possible with a number of techniques. [ABSTRACT FROM AUTHOR]

The levitation forces of a bulk YBCO superconductor in gradient varying high and low magnetic fields generated from a superconducting magnet were investigated. The magnetic field intensity of the superconducting magnet was measured when the exciting current was 90 A. The magnetic field gradient and magnetic force field were both calculated. The YBCO bulk was cooled by liquid nitrogen in field-cooling (FC) and zero-field-cooling (ZFC) condition. The results showed that the levitation forces increased with increasing the magnetic field intensity. Moreover, the levitation forces were more dependent on magnetic field gradient and magnetic force field than magnetic field intensity. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Pulmonary surfactant-associated protein B (SP-B), which is synthesized and secreted by alveolar epithelial type II cells, is crucial for normal functioning of pulmonary surfactant. Degeneration of pulmonary surfactant is the essential cause of acute lung injury (ALI). ALI is often studied in animal models using oleic acid, and the effects of oleic acid on pulmonary surfactant and SP-B are not clear. In this study, we examined the effects of oleic acid on the A549 cell line which resembles the alveolar epithelial type II cells. MATERIALS AND METHODS: A549 cells were exposed for 24 hours to 300, 400, 500 or 600 µM of oleic acid. Cell morphological changes were observed using an inverted microscope, and cell proliferation was quantified with the Cell Counting Kit-8. Extracellular SP-B levels were assessed by ELISA, whereas intracellular SP-B expression by Western blot. RESULTS: Oleic acid caused dose-dependent changes in cell morphology of A549 cells and decreased their proliferation. This was accompanied by release of SP-B into extracellular supernatants and corresponding decrease of intracellular levels of this protein. CONCLUSIONS: Oleic acid causes a dose-dependent injury to A549 cells, release of SP-B into extracellular compartment, and decrease of intracellular SP-B expression. Our findings provide mechanistic insights into animal modeling of ALI with oleic acid. [ABSTRACT FROM AUTHOR]

Bonding behaviour with different rolling reductions was discussed by peeling test in order to determine critical reduction of thin aluminium clad steel strip bonded by cold rolling. The morphology and element distribution at the interface were observed and analysed using scanning electron microscope and energy dispersive spectrometer method, respectively. The initial bond reduction of 15-25% was suggested and the minimum reduction of 35-37% was determined based on the peel force data. At the reduction of 35%, normal stress per unit bonded length is calculated as about 3.1 N/mm, and effective peeling length of 0.035 mm is determined through the theoretical analysis, which can be used to calculate the interface bond strength by peeling test. [ABSTRACT FROM AUTHOR]

By developing a wind-vehicle-bridge coupling dynamic analysis system, the impact coefficient of traffic lows on a cable-stayed bridge and its probabilistic distribution are studied in the paper. Some important influence factors of the impact coefficient, such as the vehicle-bridge coupling effect, traveling velocity, and traffic density, are analyzed. The influence of the coupling effect between a bridge deck's buffeting and vehicles' vibration on the impact coefficient of traffic lows on a cable-stayed bridge is paid due attention to. The results show that vehicle-bridge coupling effect and surface roughness exert important influence on the impact effect of a cable-stayed bridge. Considering that impact coefficient of traffic lows on a bridge bears the characteristics of randomness, the paper, on the basis of a large number of samples, interprets the influence of traveling velocity and traffic density in view of its probabilistic distribution. In view of results derived from the coupling dynamic analysis, it is suggested that the impact coefficient be 25% for all spans of a long cable-stayed bridge like the Sutong Yangtze Bridge. [ABSTRACT FROM AUTHOR]

Based on the minimal energy principle, the shape prediction models of the 0·5 mm pitch, 16 pin quad flat no lead (QFN) package solder joints were developed. The influence of the process parameters including the pad length, the pad width and the stand-off on the solder joint shape of QFN was studied. Utilising the surface coordinate exported from the QFN solder joint shape prediction models, finite element analysis (FEA) models were set up and then the non-linear FEA of the QFN solder joints under thermal cycles was performed by ANSYS. The stress–strain distribution within the solder joints and the maximum strain range of the solder joint were determined. The thermal fatigue life of the QFN solder joint was calculated based on the maximum strain range and the Coffin–Manson equation. The results show that the process parameters influence the QFN solder joint shape distinctly, and the QFN solder joint with different pad lengths, pad widths and stand-offs has various stress–strain distributions and fatigue life. The QFN solder joint with a pad length of 0·7 mm, a pad width of 0·28 mm and a stand-off of 0·125 has a fatigue life of 252 cycles under thermal cycles. [ABSTRACT FROM AUTHOR]

The article present a case study of a 34-year-old man with 13-year history of type 1 diabetes mellitus presented with diabetic ketoacidosiscoma. It mentions abdominal computed tomography (CT) scan showed a mildly enlarged liver with increased density as compared with spleen; and also mentions the patient was diagnosed with glycogenic hepatopathy (GH) due to diabetes mellitus.