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The close correlation observed between emission state and spin-down rate change of pulsars has many implications both for the magnetospheric physics and the neutron star interior. The middle-aged pulsar PSR J0738-4042, which had been observed to display variations in the pulse profile associated with its spin-down rate change due to external effects, is a remarkable example. In this study, based on the 12.5 yr combined public timing data from UTMOST and Parkes, we have detected a new emission-rotation correlation in PSR J0738-4042 concurrent with a glitch. A glitch that occurred at MJD 57359 (5) (2015 December 3) with Δν/ν ∼ 0.36(4) × 10−9 is the first glitch event observed in this pulsar, and is probably the underlying cause of the emission-rotation correlation. Unlike the usual post-glitch behaviours, the braking torque on the pulsar has continued to increase over 1380 d, corresponding to a significant decrease in |$\ddot{\nu }$|⁠. As for changes in the pulse profile after the glitch, the relative amplitude of the leading component weakens drastically, while the middle component becomes stronger. A combined model of crustquake induced platelet movement and vortex creep response is invoked to account for this rare correlation. In this scenario, magnetospheric state-change is naturally linked to the pulsar-intrinsic processes that give rise to a glitch. [ABSTRACT FROM AUTHOR]

PSR J1048 |$-$| 5832 (B1046 |$-$| 58) is a Vela-like pulsar that has exhibited multiple glitch events. In this study, we analyse the timing data spanning nearly 16 yr, acquired from both the Fermi Gamma-ray Space Telescope and the Parkes 64 m radio telescope. As a result, a total of five glitches are detected within this data set. Among them, a previously unknown small glitch is newly found at MJD 56985(9) (November 24, 2014), making it the smallest glitch recorded from this source so far. The increments of the spin frequency and its first derivative are |$\Delta \nu \approx 2.2(3) \times 10^ {-8}$|  Hz, and |$\Delta \dot{\nu } \approx 3(2) \times 10^ {-15}$|  s |$^{-2}$|⁠ , respectively. Significant changes in the integrated normalized mean pulse profile are detected following three of the five glitch events, notably in the radio band. Although no evidence of a correlation is found between the spin-down rate and profile evolution, the jump phenomenon of |$W_{55}$| (pulse width at the 55% peak amplitude) after the glitch in the narrow mode suggests that the glitch may influence the profile change. We discuss the influence of glitches on the pulsar's emission properties in terms of platelet motion by a crustquake and also put constraints on the equation of state from the moment of inertia and response time-scales of involved superfluid layers inside the neutron star. [ABSTRACT FROM AUTHOR]

We investigate the energy spectrum of systems of two, three, and four spin-1/2 fermions with short range attractive interactions both exactly and within the scattering length approximation. The formation of molecular bound states and the ferromagnetic transition of the excited scattering state are examined systematically as a function of the two-body scattering length. Identification of the upper branch (scattering states) is discussed and a general approach valid for systems with many particles is given. We show that an adiabatic ferromagnetic transition occurs, but at a critical transition point kFa much higher than predicted from previous calculations, almost all of which use the scattering length approximation. In the four-particle system the discrepancy is a factor of 2. The exact critical interaction strength calculated in the four-particle system is consistent with that reported by experiment. To make comparisons with the adiabatic transition, we study the quench dynamics of the pairing instability using the eigenstate wave functions. [ABSTRACT FROM AUTHOR]

In this work, resistance spot welding of Mg alloy AZ31 sheets was investigated in as received and acid cleaned surface conditions. As received sheets had higher contact resistance which required lower current thresholds for weld initiation and for four root t nugget size (where t is sheet thickness). However, it also led to both serious expulsion and internal defects. The fracture mode of welds in as received sheets was interfacial failure while that of the acid cleaned specimens shifted from interfacial to nugget pullout and exhibited better strength. The acid cleaned sheets also produced less damage on electrode tip faces. [ABSTRACT FROM AUTHOR]

Product development is complicated systematic engineering. The development of a successful product is achieved through cooperation between various design teams and utilisation of a number of design resources that exist in various disciplines, organisations and locations. As product complexity increases, product designers are required to collaborate with others to develop high-quality products. In this process, an effective solution is required from a knowledge resources provider for them to be able to acquire and share knowledge resources in various teams, locations, and domains. Based on the Internet, a solution for a knowledge resources provider, called a web-based product development support system (WPDSS), is proposed in this paper. The structure and implementation of the WPDSS system are both discussed in detail. Issues concerning development of the WPDSS system such as system structure, knowledge representation, and knowledge searches are investigated. Based on design of a rotor-bearing system of turbine machinery, a prototype of the WPDSS is developed to validate the feasibility of the proposed solution. [ABSTRACT FROM AUTHOR]

The article states that due to the potential integration of microelectronics and optoelectronics, the growth of Gallium nitride (GaN) on silicon (Si) substrates attracts a lot of attention. A major challenge in the growth of GaN on Si is the large mismatch of the in-plane thermal expansion coefficient, which leads to cracking in the GaN layer when cooling the heterostructure from the growth temperature to room temperature. The authors in this article report on the growth and properties of epitaxial GaN layers on Si compound using metalorganic chemical vapor deposition.

We present a timing analysis of PSR J1602–5100 using approximately seven years of observations from the Parkes 64-m radio telescope. A slow glitch that occurred between 2008 September 24 and 2010 May 14 (MJDs 54733 and 55330) is identified. During this time, the pulsar showed a slow exponential growth in the spin frequency ν , and the spin-down rate | ν ˙ | suddenly decreased to a peak value, followed by a linear return to its initial value. Our measurements of the maximum Δ ν and Δ ν ˙ are 176 nHz and 3.58 × 10 − 15 s − 2 , corresponding to fractional sizes of 152 × 10 − 9 (Δ ν / ν) and − 38.6 × 10 − 3 (Δ ν ˙ / ν ˙) , respectively. This is the largest slow glitch observed so far. Moreover, more complex changes in the shape of the pulse profile are considered to be associated with this unusual glitch activity. [ABSTRACT FROM AUTHOR]

We present timing solutions from the Fermi-LAT observations of gamma-ray pulsars PSR J0835 − 4510 (Vela), PSR J1023−5746, PSR J2111+4606, and PSR J2229+6114. Data ranges for each pulsar extend over a decade. From data analysis, we have identified a total of 20 glitches, 11 of which are new discoveries. Among them, 15 glitches are large ones with Δν/ν ≳ 10−6. PSR J1023−5746 is the most active pulsar with glitch activity parameter being A g = 14.5 × 10−7 yr−1 in the considered data span and should be a target for frequently glitching Vela-like pulsars in future observations. We have done fits within the framework of the vortex creep model for 16 glitches with Δν/ν ≳ 10−7. By theoretical analysis of these glitches, we are able to obtain important information on the structure of neutron star, including moments of inertia of the superfluid regions participated in glitches and coupling time-scales between various stellar components. The theoretical prediction for the time to the next glitch from the parameters of the previous one is found to be in qualitative agreement with the observed inter-glitch time-scales for the considered sample. Recoupling time-scales of the crustal superfluid are within the range of theoretical expectations and scale inversely with the spin-down rate of a pulsar. We also determined a braking index n = 2.63(30) for PSR J2229+6114 after glitch-induced contributions have been removed. [ABSTRACT FROM AUTHOR]

Single phase AlN nanowires are fabricated by a sublimation method. They were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), typical selected area electron diffraction (SAED) and high-resolution transmission electron microscopy (HRTEM). The SEM and TEM images show that most of the nanowires have diameters of about 10-60 nm. The crystal structure of AlN nanowires revealed by XRD, SAED and HRTEM shows the AlN nanowires have a wurtzite structure. [ABSTRACT FROM AUTHOR]

The correlation between colossal magnetocapacitance (CMC) and colossal magnetoresistance (CMR) in CdCr2S4 system has been revealed. The CMC is induced in polycrystalline Cd0.97In0.03Cr2S4 by annealing in cadmium vapor. At the same time, an insulator-metal transition and a concomitant CMR are observed near the Curie temperature. In contrast, after the same annealing treatment, CdCr2S4 displays a typical semiconductor behavior and does not show magnetic field dependent dielectric and electric transport properties. The simultaneous occurrence or absence of CMC and CMR effects implies that the CMC in the annealed Cd0.97In0.03Cr2S4 could be explained qualitatively by a combination of CMR and Maxwell-Wagner effect. [ABSTRACT FROM AUTHOR]

A ferromagnetic shape memory alloy was utilized to construct a Ni43Mn41Co5Sn11/Pb(Zr,Ti)O3 laminate. Large direct and converse magnetoelectric (ME) effects were observed at resonance frequencies around the martensitic transition temperature of Ni43Mn41Co5Sn11 alloy, and the temperature affects the ME properties remarkably. The ME coefficients respond almost linearly to the applied ac electric or magnetic field. The mechanism of both direct and converse ME effects in the laminate is discussed. [ABSTRACT FROM AUTHOR]

Background. To evaluate iodine status and the prevalence of thyroid disorders in different populations of Zhoushan Island, China. Methods. A total of 3284 inhabitants of Zhoushan Island were surveyed, including 1389 urban residents, 737 salt workers, 502 peasants, 362 fishermen, and 294 monks from Mount Putuo. All subjects, except for salt workers, consumed iodized salt. A thyroid ultrasound was performed and serum levels of thyroid hormones and thyroid peroxidase antibody were measured. Results. The median urinary iodine concentration was significantly higher in subjects who consumed iodized salt than in those who consumed non-iodized salt. No significant differences were noted in the prevalence of thyroid ultrasound abnormalities and functional thyroid disorders between subjects who consumed non-iodized and iodized salt except between salt workers and monks from Mount Putuo. The prevalence of thyroid ultrasound abnormalities differed significantly between males and females and was positively correlated with advanced age (r=0.212, P<0.001). Conclusions. Iodine intake is considered adequate, more than adequate, or excessive amongst the study populations. The prevalence of both thyroid ultrasound abnormalities and functional thyroid disorders is extremely high in Zhoushan Island. Advanced age and female gender are significant predictors of thyroid ultrasound abnormalities. [ABSTRACT FROM AUTHOR]

InAs quantum dots (QDs) were successfully formed in single-crystalline Si by sequential ion implantation and subsequent milliseconds range flash lamp annealing (FLA). Samples were characterized by μ-Raman spectroscopy, Rutherford Backscattering Spectrometry (RBS) high-resolution transmission electron microscopy (HRTEM) and low temperature photoluminescence (PL). The Raman spectrum shows two peaks at 215 and 235 cm corresponding to the transverse optical (TO) and longitudinal optical (LO) InAs phonon modes, respectively. The PL band at around 1.3 μm originates from the InAs QDs with an average diameter 7.5±0.5 nm and corresponds to the increased band gap energy due to the strong quantum confinement size effect. The FLA of 20 ms is sufficient for InAs QDs formation. It also prevents the out-diffusion of implanted elements. Moreover, the silicon layer amorphized during ion implantation is recrystallized by solid-phase epitaxial regrowth during FLA. [ABSTRACT FROM AUTHOR]

To evaluate the role of interleukin-6 (IL-6) in arthritis induced by Staphylococcus aureus, a chicken model was developed for study. A total of 120 healthy broilers (8 wk old) were randomly divided into 4 groups. Two groups were injected with 0.35 mL of Staph. aureus (7.1 × 109 cfu/mL) into the right hock joints and the other 2 were injected with 0.35 mL of sterile saline into the same joints. One group of each of the 2 treatment groups was fed levofloxacin at a dose of 5 mg/kg of BW on the third day postinoculation for 4 successive days. Chicken blood samples were obtained on d 0, 1, 4, 7, 14, 21, 28, and 35 postinoculation. Chicken IL-6 (chIL-6) activities and concentrations in serum were quantified by B9 bioassay and human IL-6 ELISA, respectively. The results showed that chIL-6 activities and concentrations were reduced (P < 0.05) in the serum of infected broilers treated with levofloxacin compared with birds injected only with Staph. aureus. Levofloxacin treatment had no effect on IL-6 activities and concentrations in uninfected broilers. There was a strong correlation (r = 0.91) between serum chIL-6 activities by the B9 bioassay and serum IL-6 concentrations determined by the human IL-6 ELISA. We concluded that chIL-6 is involved in the progression of chicken arthritis induced by Staph. aureus, and that it contributes to disease incidence and mortality. [ABSTRACT FROM AUTHOR]

We present a study of the magnetic properties of oxidized Co nanoparticles with an average grain size of 3 nm, embedded in an amorphous Al2O3 matrix. These nanoparticles can be considered as imperfect Co-core CoO-shell systems. Magnetization measurements after magnetic field cooling show a vertical shift of the hysteresis loop, while no exchange bias is observed. With a simple model, we show that there is a critical grain size for hybrid ferromagnetic-antiferromagnetic particles, below which exchange bias is absent for any ratio of ferromagnetic and antiferromagnetic constituents. The reason is that the interfacial exchange energy dominates over other energies in the system due to a large surface-to-volume ratio in the nanoparticles. [ABSTRACT FROM AUTHOR]