Spontaneous spinning of a magnet levitating over a superconductor

A permanent magnet levitating over a superconductor is found to spontaneously spin, overcoming resistance to air friction. We explain the physics behind this remarkable effect.Comment: See http://physics.ucsd.edu/~jorge/spinning.html for movie clips of the effec

Role of Environmental Sustainability, Psychological and Managerial Supports for Determining Bankers Green Banking Usage Behavior: An Integrated Framework '

PURPOSE: Green banking, an ethical banking concept, concentrates on environmental protection and encourages social and environmental sustainability, perceived cognitive efforts, and subjective norms ensuring ecologically responsive banking services. Consequently, although there have been considerable green banking attempts in Bangladesh, it is yet unknown how environmental sustainability, perceived cognitive effort, and subjective norms affect usage behavior. The present research aims to uncover this gap, extending the Theory of Reasoned Action (TRA) to examine the determinants of the bankers’ green banking usage behavior during COVID-19. METHODS: Data were collected from 366 bankers in Bangladesh using a purposive sampling technique and analyzed with structural equation modeling (SEM) using SMART PLS 3 software. FINDINGS: The study found management support (0.291, t-statistics = 1.978, p 0.000), environmental sustainability (β = 0.278, t-statistics = 2.752, p < 0.001), perceived cognitive efforts (β = 0.401, t-statistics = 3.549, p < 0.000), and subjective norms (β = 0.309, t-statistics = 4.352, p < 0.000) influence bankers’ attitudes. Whereas environmental sustainability (β = 0.503, t-statistics = 3.726, p < 0.001), perceived cognitive efforts (β = 0.103, t-statistics = 2.020, p < 0.002), subjective norms (β = 0.281, t-statistics = 4.607, p < 0.000), and attitudes (= 0.602, t-statistics = 5.523, p 0.015) influence bankers’ green banking usage behavior. Finally, the mediating role of management supports, environmental sustainability, cognitive efforts and subjective norms on green banking usage behavior through attitudes was significant. CONTRIBUTION/CONCLUSION: The study contributed to existing literature validating the proposed holistic framework applying TRA and three contemporary dimensions explaining bankers’ behavior toward green banking practice. Finally, the implementers should focus on green banking practices as green banking is one of the key strategies to protect the environment, assure social justice, and create economic success

Evaluation of a Community-Based Positive Youth Development Program for Adolescents with Greater Psychosocial Needs: Views of the Program Participants

The present study attempted to investigate the perceptions of Chinese secondary school students with greater psychosocial needs of the Tier 2 Program in the community-based phase of P.A.T.H.S. Project in Hong Kong (n=4245). Using a subjective outcome evaluation tool (Form C), the results revealed that a great majority of the students held positive attitudes toward the program, implementers and the effectiveness of the program. Also, the three domains of the program (“program quality”, “implementer quality” and “program effectiveness”) were significantly associated with each other. In line with previous findings, both program content and program implementer quality were significant predictors of program effectiveness. The current findings further reinforce the thesis that the community-based Tier 2 programs of the P.A.T.H.S. Project are effective in promoting the holistic development of adolescents with greater psychosocial needs in Hong Kong

The Wide Integral Field Infrared Spectrograph: Commissioning Results and On-sky Performance

We have recently commissioned a novel infrared ($0.9-1.7$ $\mu$m) integral field spectrograph (IFS) called the Wide Integral Field Infrared Spectrograph (WIFIS). WIFIS is a unique instrument that offers a very large field-of-view (50$^{\prime\prime}$ x 20$^{\prime\prime}$) on the 2.3-meter Bok telescope at Kitt Peak, USA for seeing-limited observations at moderate spectral resolving power. The measured spatial sampling scale is $\sim1\times1^{\prime\prime}$ and its spectral resolving power is $R\sim2,500$ and $3,000$ in the $zJ$ ($0.9-1.35$ $\mu$m) and $H_{short}$ ($1.5-1.7$ $\mu$m) modes, respectively. WIFIS's corresponding etendue is larger than existing near-infrared (NIR) IFSes, which are mostly designed to work with adaptive optics systems and therefore have very narrow fields. For this reason, this instrument is specifically suited for studying very extended objects in the near-infrared such as supernovae remnants, galactic star forming regions, and nearby galaxies, which are not easily accessible by other NIR IFSes. This enables scientific programs that were not originally possible, such as detailed surveys of a large number of nearby galaxies or a full accounting of nucleosynthetic yields of Milky Way supernova remnants. WIFIS is also designed to be easily adaptable to be used with larger telescopes. In this paper, we report on the overall performance characteristics of the instrument, which were measured during our commissioning runs in the second half of 2017. We present measurements of spectral resolving power, image quality, instrumental background, and overall efficiency and sensitivity of WIFIS and compare them with our design expectations. Finally, we present a few example observations that demonstrate WIFIS's full capability to carry out infrared imaging spectroscopy of extended objects, which is enabled by our custom data reduction pipeline.Comment: Published in the Proceedings of SPIE Astronomical Telescopes and Instrumentation 2018. 17 pages, 13 figure

BSAVA Formulary: Your questions answered

A new edition of the BSAVA Small Animal Formulary has been published. Ian Ramsey explains what is in and what is out of this new version

Magnetic Field Strength in the Upper Solar Corona Using White-light Shock Structures Surrounding Coronal Mass Ejections

To measure the magnetic field strength in the solar corona, we examined 10 fast (> 1000 km/s) limb CMEs which show clear shock structures in SOHO/LASCO images. By applying piston-shock relationship to the observed CME's standoff distance and electron density compression ratio, we estimated the Mach number, Alfven speed, and magnetic field strength in the height range 3 to 15 solar radii (Rs). Main results from this study are: (1) the standoff distance observed in solar corona is consistent with those from a magnetohydrodynamic (MHD) model and near-Earth observations; (2) the Mach number as a shock strength is in the range 1.49 to 3.43 from the standoff distance ratio, but when we use the density compression ratio, the Mach number is in the range 1.47 to 1.90, implying that the measured density compression ratio is likely to be underestimated due to observational limits; (3) the Alfven speed ranges from 259 to 982 km/s and the magnetic field strength is in the range 6 to 105 mG when the standoff distance is used; (4) if we multiply the density compression ratio by a factor of 2, the Alfven speeds and the magnetic field strengths are consistent in both methods; (5) the magnetic field strengths derived from the shock parameters are similar to those of empirical models and previous estimates.Comment: Accepted for publication in ApJ, 11 Figures, 1 Tabl

Corrosion of aluminium metal in OPC- and CAC-based cement matrices

Corrosion of aluminium metal in ordinary Portland cement (OPC) based pastes produces hydrogen gas and expansive reaction products causing problems for the encapsulation of aluminium containing nuclear wastes. Although corrosion of aluminium in cements has been long known, the extent of aluminium corrosion in the cement matrices and effects of such reaction on the cement phases are not well established. The present study investigates the corrosion reaction of aluminium in OPC, OPC-blast furnace slag (BFS) and calcium aluminate cement (CAC) based systems. The total amount of aluminium able to corrode in an OPC and 4:1 BFS:OPC system was determined, and the correlation between the amount of calcium hydroxide in the system and the reaction of aluminium obtained. It was also shown that a CAC-based system could offer a potential matrix to incorporate aluminium metal with a further reduction of pH by introduction of phosphate, producing a calcium phosphate cement

Effects of charge doping and constrained magnetization on the electronic structure of an FeSe monolayer

The electronic structural properties in the presence of constrained magnetization and a charged background are studied for a monolayer of FeSe in non-magnetic, checkerboard-, and striped-antiferromagnetic (AFM) spin configurations. First principles techniques based on the pseudopotential density functional approach and the local spin density approximation are utilized. Our findings show that the experimentally observed shape of the Fermi surface is best described by the checkerboard AFM spin pattern. To explore the underlying pairing mechanism, we study the evolution of the non-magnetic to the AFM-ordered structures under constrained magnetization. We estimate the strength of electronic coupling to magnetic excitations involving an increase in local moment and, separately, a partial moment transfer from one Fe atom to another. We also show that the charge doping in the FeSe can lead to an increase in the density of states at the Fermi level and possibly produce higher superconducting transition temperatures