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We discuss the apparent paradox that the energy released in a fission bomb explosion is independent of the energy ϵ liberated by each fissioning nucleus. The paradox is resolved by noting that a larger value of ϵ results in a shorter "burn time"; this stops the chain reaction sooner and results in fewer nuclei being fissioned. Editor's Note: Both awe-inspiring and terrifying, a nuclear explosion is a spectacular display of microscopic physics profoundly affecting the human scale. This paper explores the physics of nuclear explosions and addresses the counter-intuitive fact that the total energy released by a fission bomb is independent of the energy released in a single fission. While this was known to the scientists who developed the atomic bomb, much of their work is classified and their knowledge remains inaccessible to the general public. With only a few historical documents to go on, the authors of this article attempt to recreate a calculation by Manhattan Project scientists and clearly show why the total energy yield is independent of the energy released by each fissioning nucleus. This article will be of interest to readers interested in nuclear physics or in the history of the Manhattan Project. [ABSTRACT FROM AUTHOR]

Treatments for organ‐confined prostate cancer include external beam radiation therapy, radical prostatectomy, radiotherapy/brachytherapy, cryoablation and high‐intensity focused ultrasound. None of these are cancer‐specific and are commonly accompanied by side effects, including urinary incontinence and erectile dysfunction. Moreover, subsequent surgical treatments following biochemical recurrence after these interventions are either limited or affected by the scarring present in the surrounding tissue. Carnosine (β‐alanyl‐L‐histidine) is a histidine‐containing naturally occurring dipeptide which has been shown to have an anti‐tumorigenic role without any detrimental effect on healthy cells; however, its effect on prostate cancer cells has never been investigated. In this study, we investigated the effect of carnosine on cell proliferation and metabolism in both a primary cultured androgen‐resistant human prostate cancer cell line, PC346Flu1 and murine TRAMP‐C1 cells. Our results show that carnosine has a significant dose‐dependent inhibitory effect in vitro on the proliferation of both human (PC346Flu1) and murine (TRAMP‐C1) prostate cancer cells, which was confirmed in 3D‐models of the same cells. Carnosine was also shown to decrease adenosine triphosphate content and reactive species which might have been caused in part by the increase in SIRT3 also shown after carnosine treatment. These encouraging results support the need for further human in vivo work to determine the potential use of carnosine, either alone or, most likely, as an adjunct therapy to surgical or other conventional treatments. [ABSTRACT FROM AUTHOR]

A superconducting Transition-Edge Sensor (TES) with low- T c is essential in high resolution calorimetric detection. With the motivation of developing sensitive calorimeters for applications in cryogenic neutrinoless double beta decay searches, we have been investigating methods to reduce the T c of an Ir film down to 20 mK. Utilizing the proximity effect between a superconductor and a normal metal, we found two room temperature fabrication recipes for making Ir-based low- T c films. In the first approach, an Ir film sandwiched between two Au films, a Au/Ir/Au trilayer, has a tunable T c in the range of 20–100 mK depending on the relative thicknesses. In the second approach, a paramagnetic Pt thin film is used to create the Ir/Pt bilayer with a tunable T c in the same range. We present a detailed study of fabrication and characterization of Ir-based low- T c films and compare the experimental results to the theoretical models. We show that Ir-based films with a predictable and reproducible critical temperature can be consistently fabricated for use in large scale detector applications. [ABSTRACT FROM AUTHOR]

The Microchannel X-ray Telescope (MXT) will be the first focusing X-ray telescope based on a narrow field "Lobster-Eye" optical design to be flown on a satellite, namely the Sino-French mission SVOM. SVOM will be dedicated to the study of Gamma-Ray Bursts and more generally time-domain astrophysics. The MXT telescope is a compact (focal length ∼ 1.15 m) and light (< 42 kg) instrument, sensitive in the 0.2–10 keV energy range. It is composed of an optical system, based on micro-pore optics (MPOs) of 40 μ m pore size, coupled to a low-noise pnCDD X-ray detector. In this paper we describe the expected scientific performance of the MXT telescope, based on the End-to-End calibration campaign performed in fall 2021, before the integration of the SVOM payload on the satellite. [ABSTRACT FROM AUTHOR]

Purpose: Combined acetabular and pelvic ring injuries represent a unique subset of pelvic trauma and little is known regarding their complications and outcomes. We sought to further evaluate these injury patterns and quantify their outcomes. Methods: A retrospective review at a single level 1 trauma center was performed on all patients with operatively treated combined ring and acetabulum injuries during a seven-year period. Main outcome measurements include all-cause complication including residual neurologic deficit, deep infection, conversion to total hip arthroplasty, deep venous thrombosis and mortality. Results: Seventy operatively treated combined ring and acetabulum patients with one-year follow-up were reviewed. The overall complication rate was 44%. Hip dislocation occurred in 40% of the cohort and was significantly associated with residual neurologic deficit and all-cause complication. Angiography with embolization was not associated with an increased rate of deep infection. Open acetabular approaches had a significantly higher complication rate compared to percutaneous procedures. Delay to definitive fixation greater than 36 h trended toward but did not reach association with all complications. Conclusion: Combined injuries to the acetabulum and pelvic ring have high rates of complications. No individual fracture patterns were identified as risk factors, but hip dislocation was associated with an increased rate of complications. When possible, percutaneous reduction and fixation of acetabular fractures and early definitive fracture fixation lead to lower rates of complications. Use of angiography with embolization appears to be safe and does not increase the risk of infection or other complications. [ABSTRACT FROM AUTHOR]

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We are developing a low- T c TES-based large-area and low-threshold detector targeting a variety of potential applications. The detector consists of a 50.8-mm-diameter Si wafer as the substrate and radiation absorber, a single Ir/Pt bilayer TES sensor in the center, and normal metal Au pads added to the TES to strengthen the TES–absorber thermal coupling. Tight TES–absorber thermal coupling improves detector sensitivity and response uniformity. Here, we report on the electron–phonon (e–ph) coupling strengths for the Ir/Pt bilayer and Au that are measured with our prototype detectors and TES devices. We found that a second weak thermal link besides the one due to e–ph coupling in Ir/Pt or Au was required to explain our data. With the effects of the second weak link accounted for, the extracted e–ph coupling constant Σ for Ir/Pt bilayer in the T c range between 32 and 70 mK is 1.9 × 10 8 WK - 5 m - 3 , and Σ 's for Au at 40 mK and 55 mK are 2.2 × 10 9 WK - 5 m - 3 and 3.2 × 10 9 WK - 5 m - 3 , respectively. [ABSTRACT FROM AUTHOR]

Advances in the development of prediction tools for wave overtopping allow now for overtopping volumes to be estimated with good accuracy, with the combined use of mean overtopping rates and maximum wave by wave overtopping volumes in a sequence of wave overtopping events. While previous literature has tended to focus on mean overtopping rates at coastal structures, limited studies have investigated the wave by wave overtopping volumes at coastal sea defences; in particular, a paucity of studies have focussed on the prediction of the shape parameter in the Weibull distribution (i.e., Weibull b) of overtopping volumes. This study provides new insights on the probability distribution of individual wave overtopping volumes at plain vertical seawalls by analysing the measured Weibull b values derived from a series of laboratory experiments on seawalls performed on a wide range of wave conditions and crest freeboards. The influence of wave conditions (wave steepness, significant wave height), structural parameters (crest freeboard, toe water depth), impulsiveness, probability of overtopping waves, and overtopping discharge on Weibull b parameter were examined, and then compared with the well-established empirical formulae. For the conditions covered within this study, it was found that the probability distribution of wave-by-wave overtopping volumes follow a 2-parameter Weibull distribution. No apparent differences in Weibull b values were reported with the variation of incident wave steepness and impulsiveness parameter. Results of this study revealed that Weibull b values at vertical walls, subjected to non-impulsive wave conditions, can be predicted reasonably well using relative freeboard and relative overtopping rates. A new unified formula is proposed for the estimation of Weibull b values at vertical walls under impulsive and non-impulsive wave attack. [ABSTRACT FROM AUTHOR]

The formation of the vortex-antivortex-vortex (v-av-v) metastable remanent states in elongated magnetic elements have been systematically investigated using micromagnetic modeling. It is demonstrated that the v-av-v magnetization pattern can be effectively stabilized by exciting the single vortex state with an external RF field. Furthermore, we show that a set of different polarity combinations of the vortex cores can be achieved by adjusting the frequency and amplitude of the excitation field. The corresponding dynamic response in time- and frequency-domain has also been presented. Owing to the diversity of the collective modes with different vortex-antivortex combinations, this system may open promising perspectives in the area of spin transfer torque oscillators. [ABSTRACT FROM AUTHOR]

The ability to read and compose original scientific literature is critical to educating informed citizens, yet may be severely lacking in undergraduate curricula. We developed a linked course offering in fall 2017 consisting of a 16-student group taking an introductory biology course paired with a first-year composition course. The composition course focused specifically on scientific literature composed in the Introduction, Methods, Results, and Discussion (IMRaD) structure. In the composition course, instruction focused on helping students conceptualize and compose proposals, poster presentations, and manuscripts based on their lab activities. We surveyed for prior experience with scientific literature and self-reported reading and writing confidence. Participants in the linked courses showed an improvement in self-reported ability and confidence in writing compared to a control group that did not participate. We assembled a rubric assessing correct IMRaD structure and used it to assess composition before and after the linked courses. Adherence to IMRaD improved significantly for the Methods section. Our experiences indicate that learning communities can be useful pedagogies to provide students with confidence and learning gains that facilitate use of information and communication. [ABSTRACT FROM AUTHOR]

One way of making a transition-edge sensor (TES) is by utilizing the proximity effect, in which the T C of a superconducting film is reduced with a normal metal film in metallic contact. The T C of a bilayer TES can be estimated by solving the Usadel equations with given boundary conditions. The classical boundary conditions of a bilayer include a specific interface resistance being temperature-independent. In this paper, we will introduce a temperature-dependent specific interface resistance. By fitting the measured T C data of Ir/Au bilayers from the literature to a T C calculation model, we will compare the fit parameters and fit errors with the temperature-dependent specific interface resistance described in this work and with the classical temperature-independent specific interface resistance. [ABSTRACT FROM AUTHOR]

Frequency-domain multiplexing is a readout technique for transition-edge sensor bolometer arrays used on modern cosmic microwave background experiments, including the SPT-3G receiver. Here, we present design details and performance measurements for a low-parasitic frequency-domain multiplexing readout. Reducing the parasitic impedance of the connections between cryogenic components provides a path to improve both the crosstalk and noise performance of the readout. Reduced crosstalk will in turn allow higher-multiplexing factors. We have demonstrated a factor of two improvement in parasitic resistance compared to SPT-3G hardware. Reduced parasitics also permits operation of lower-resistance bolometers optimized for improved readout noise performance. We demonstrate that a module in the prototype system has comparable readout noise performance to an SPT-3G module when operated with dark TES bolometers in the laboratory. [ABSTRACT FROM AUTHOR]

We have developed a new transition-edge sensor material with critical temperature (Tc) in the range 100–200 mK. The new material is a solid solution of two superconducting components, MoxNb1−x, co-sputtered from two high-purity single-component targets (Mo and Nb). The Tc has a minimum (dTc/dx = 0) at an intermediate concentration of the components. We have optimized the deposition parameters and composition to provide films with a sharp superconducting transition at ~ 150 mK. We investigated structural features of the films and surface morphology using X-ray diffraction (XRD) and scanning electron microscopy. The XRD measurements indicate that the grown films are polycrystalline, with a preferred orientation along the (110) crystal direction and a clear correlation between superconducting properties and film microstructure. [ABSTRACT FROM AUTHOR]

Purpose: To determine whether cytomegalovirus is causally associated with breast cancer and whether cytomegalovirus should be categorised as an oncogenic virus. Methods: We undertook a review of published epidemiological and laboratory studies, using established causal criteria: Bradford Hill criteria to determine whether cytomegalovirus is associated with breast cancer; and Evans/Mueller criteria to determine whether cytomegalovirus should be categorised as an oncogenic virus. Results: Although there are inconsistencies in the findings of published epidemiological and laboratory studies, these may be explained by factors such as: differences in timing of blood samples, differences in selection of cases and controls, or high cytomegalovirus seroprevalence among participants in the epidemiological studies; and, in the laboratory studies, differences in sample preparations, age of sample, whether or not paired breast cancer and normal breast tissue samples were used, differences in the tests, primers and/or antibodies used, differences in histological types of breast cancer studied, and/or features of the virus. Conclusions: Overall, the results of published studies of cytomegalovirus and breast cancer suggest cytomegalovirus is a causal factor for at least some types of breast cancer. If the evidence for a link between cytomegalovirus and breast cancer continues to strengthen, further research could lead to: targeted screening; therapy using antiviral drugs; and, perhaps, primary prevention of a significant proportion of breast cancer. Vaccination against viruses has already been shown to be effective in preventing cervix and liver cancer; cytomegalovirus vaccines are already under development. [ABSTRACT FROM AUTHOR]

Context. In the cooling process of a non-accreting neutron star, the composition and properties of the crust are thought to be fixed at the finite temperature where nuclear reactions fall out of equilibrium. A lower estimate for this temperature is given by the crystallization temperature, which can be as high as 7 ✕ 109 K in the inner crust, potentially leading to sizeable differences with respect to the simplifying cold-catalyzed matter hypothesis. Aims. We extend a recent work on the outer crust to the study of the crystallization of the inner crust and the associated composition in the one-component plasma approximation. Methods. The finite temperature variational equations for non-uniform matter in both the liquid and the solid phases are solved using a compressible liquid-drop approach with parameters optimized on four different microscopic models that cover current uncertainties in nuclear modeling. Results. We consider the effect of the different nuclear ingredients with their associated uncertainties separately: the nuclear equation of state, the surface properties in the presence of a uniform gas of dripped neutrons, and the proton shell effects arising from the ion single-particle structure. Our results suggest that the highest source of model dependence comes from the smooth part of the nuclear functional. Conclusions. We show that shell effects play an important role at the lowest densities close to the outer crust, but the most important physical ingredient to be settled for a quantitative prediction of the inner crust properties is the surface tension at extreme isospin values. [ABSTRACT FROM AUTHOR]

Micropore optics have recently been implemented in a lobster eye geometry as a compact X-ray telescope. Fields generated by rare-earth magnets are used to reduce the flux of energetic electrons incident upon the focal plane detector in such a setup. We present the design and implementation of the electron diverters for X-ray telescopes of two upcoming missions: the microchannel X-ray telescope onboard the space-based multiband astronomical variable objects monitor and the soft X-ray instrument onboard the solar wind magnetosphere ionosphere link explorer. Electron diverters must be configured to conform to stringent limits on their total magnetic dipole moment and be compensated for any net moment arising from manufacturing errors. The two missions have differing designs, which are presented and evaluated in terms of the fractions of electrons reaching the detector, as determined by relativistic calculations of electron trajectories. The differential flux of electrons to the detector is calculated, and the integrated electron background is determined for both designs. [ABSTRACT FROM AUTHOR]

Exchange bias effects have been studied in elliptical dots composed of ferromagnetic Ni80Fe20–antiferromagnetic Ir20Mn80 bilayers. The magnetization reversal mechanisms and magnetic configurations have been investigated by magneto-optic Kerr effect and magnetic force microscopy. Although the obtained bias fields in these dots are relatively small, the magnetization reversal is found to be influenced by the ferromagnetic–antiferromagnetic coupling. Namely, for some off-axis angles of measurement, the magnetization reversal mechanism of the Ni80Fe20–Ir20Mn80 ellipses depends on whether exchange bias is induced along the minor or major axis of the ellipses. Hence, exchange bias is shown to be an effective means for tailoring the magnetization reversal of elliptical dots after sample fabrication. [ABSTRACT FROM AUTHOR]

An in situ environmental transmission electron microscopy study of the nucleation and growth of oxide islands during the early-stage oxidation of (001) Cu1-xAux alloys (x<=38 at. %) was undertaken in order to investigate the effects of alloying on oxide island nucleation behavior and growth kinetics. The kinetic data reveal that Au enhances the nucleation density of oxide islands and suppresses their growth rate. Our results provide insight into reasons for the decreased passivation properties of Cu when alloyed with Au. [ABSTRACT FROM AUTHOR]

We explore the magnetic properties of Co and Fe on a Pt(997) vicinal single crystal by means of reflection high energy electron diffraction and the surface magneto-optical Kerr effect. Both Co and Fe are grown at room temperature as wedges with thickness ranging from 0 to 3.5 ML (monolayer). We find that Co and Fe show layer-by-layer growth followed by three dimensional growth as the coverage increases due to the large lattice mismatch. Co and Fe exhibit ferromagnetism down to 0.2 ML coverage due to the strong anisotropy. The symmetry breaking at the surface results in the magnetic easy axis of the atomic layers along the surface normal direction. The coercivity of both Fe and Co atomic layers fit an exponential decay with temperature that can be understood as being due to thermally activated, nonequilibrium spin dynamics. The magnetic anisotropy energy per atom is extracted by fitting the experimental data. [ABSTRACT FROM AUTHOR]

The original estimate of the fissility of very heavy nuclei made by Meitner and Frisch can be derived without resorting to Rayleigh's theory of vibrating liquid drops and Legendre polynomials. A simple expression, familiar from the theory of the Wilson cloud chamber, suffices. [ABSTRACT FROM AUTHOR]

Rib fractures are associated with significant morbidity and mortality. Ultrasound-guided thoracic paravertebral catheter insertion has been described for the management of pain secondary to rib fractures. We conducted a retrospective observational study of all patients with rib fractures who had a paravertebral catheter inserted for analgesia provision over a 4-year period. Data from the Trauma Audit and Research Network were used to compare patients with rib fractures who were managed with paravertebral catheters to those managed with systemic analgesia. A total of 314 consecutive paravertebral catheters were inserted in 290 patients. Five (1.9%) catheters were removed due to ineffective analgesia. Other minor complications occurred in three cases (0.96%). The proportion of rib fracture patients managed with paravertebral catheters increased from 31/200 (15.5%) in the first year of study to 81/168 (48.2%) in the fourth; over this time-period the observed:predicted mortality ratio fell from 1.04 to 0.66. Proportional hazard regression with and without propensity score matching demonstrated a reduction in mortality associated with paravertebral catheter use, but this became statistically non-significant when time-dependent analysis was used. Paravertebral catheters are a safe and effective technique for rib fracture analgesia; however, our data were insufficient to demonstrate any improvement in mortality. [ABSTRACT FROM AUTHOR]

A very slight change in some nuclear properties would have been enough to make the fission chain reaction impossible. If the alpha-decay energy of 235U, the only naturally occurring fissile nuclide, were just 0.1 MeV higher than it actually is so little would remain in the Earth that extracting a critical mass would be close to impossible. Moreover, even with a sufficient abundance of 235U, if its scission point were shifted inwards by at most 2 fm not enough secondary neutrons would be emitted for a chain reaction to be possible. Speculating within the framework of the multiverse concept, we ask whether there could be a universe similar to ours in which intelligent life can emerge but in which the fission chain reaction is impossible. [ABSTRACT FROM AUTHOR]

Summary: Adolescents affected by overweight or obesity report similar quality of life to adolescents with cancer. While weight management is important for physiological outcomes, it is unclear whether weight management improves quality of life in this age group. This meta‐analysis assessed the impact of multicomponent weight management interventions on quality of life in adolescents affected by overweight or obesity. Ovid PsycINFO, Ovid Medline, Ovid Embase, Cochrane Library, Scopus and CINAHL Plus databases were searched up to July 2017. Eight eligible studies were randomized controlled trials of multicomponent weight management interventions for adolescents (10 to 19 years) affected by overweight or obesity, with quality of life and weight measurements. Meta‐analyses determined a positive effect on quality of life (mean difference 0.20 [0.11, 0.29]; p < 0.01) and weight (mean difference 0.30 [0.12, 0.47]; p < 0.01) following intervention. There was no correlation between weight loss and improvements in quality of life (R2 = 0.103). Rather than weight loss, intervention factors such as parental involvement, group settings and a focus on psychosocial well‐being appeared linked to improvements in quality of life. The reduced quality of life reported by this group may be due to social consequences of obesity, rather than actual weight. [ABSTRACT FROM AUTHOR]

The theory of the nuclear energy-density functional is used to provide a unified and thermodynamically consistent treatment of all regions of cold non-accreting neutron stars. In order to assess the impact of our lack of complete knowledge of the density dependence of the symmetry energy on the constitution and the global structure of neutron stars, we employ four different functionals. All of them were precision fitted to essentially all the nuclear mass data with the Hartree–Fock–Bogoliubov method and two different neutron-matter equations of state based on realistic nuclear forces. For each functional, we calculate the composition, the pressure–density relation, and the chemical potentials throughout the star. We show that uncertainties in the symmetry energy can significantly affect the theoretical results for the composition and global structure of neutron stars. To facilitate astrophysical applications, we construct analytic fits to our numerical results. [ABSTRACT FROM AUTHOR]

Microscopic simulation is used to clarify the status of stochastic theories of homogeneous chemical systems operating in the multiple steady state region. The results demonstrate the failure of the Langevin approach, but show excellent agreement with the master equation formulation. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A microscopic computer experiment is set up to investigate the statistical properties of far from equilibrium homogeneous chemical systems undergoing instabilities. Sustained periodic behavior of limit cycle type is observed. Both the frequency and the amplitude of the oscillations are found to be in good agreement with the macroscopic description. A comparison with the stochastic theory of chemical systems based on master equation formalism is also carried out. The dynamical and static correlation functions obtained by these two procedures are in very good agreement. [ABSTRACT FROM AUTHOR]

Describes a study which compared the structure and stoichiomestry of the films on aluminum[sub2]oxygen[sub3] with the films on yttria-stabilized zirconium dioxide (YSZ) and magnesium oxide. Importance of aluminum[sub2]oxygen[sub3] substrate; Superconducting onset temperature of the film; Features of film-substrate interactions.

Investigates axial profiles of thermal wall loading and radiation output in a direct current vortex-stabilized arc. Information on the theory; Description of the experimental apparatus; Results of the experiments.

Investigates the effect of uniaxial deformation on the giant magnetoresistance (GMR) effect in melt-spun Co-Cu ribbons. Increase of structural disorder and resistivity; Degradation of the GMR effect; Effect of the deformation of the metastable alloy prior to precipitation of the Co particles on the particle nucleation process.

Deals with a study which examined the antiferromagnetic coupling between two magnetic layers across intervening nonmagnetic layers found in iron/chromium sandwiches. Growth and characterization of the sandwiches; Basic principles of magnetic coupling; Oscillation of the magnetic coupling in the sandwiches.

We report the fabrication process, magnetic behavior, as well as the surface modification of ferromagnetic microdisks suspended in aqueous solution. They posses unique properties such as high magnetization of saturation, zero remanence due to spin vortex formation, intrinsic spin resonance at low frequencies, and the capability of delivering various biomolecules at once. Furthermore, because of their anisotropic shape, our magnetic particles rotate under alternating magnetic fields of small amplitude. This can be used to promote the idea of advanced therapies, which include combined drug delivery and magnetomechanical cell destruction when targeting tumor cells. The approach enables us to fabricate suitable magnetic carriers with excellent size tolerances, and then release them from the wafer into solution, ready for surface modification and therapeutic use. The particles have a magnetic core and are covered with few nanometers of gold on each side to provide stability at ambient conditions as well as biocompatibility and selective adhesion functions. A successful attempt to bind thiolates, including SH-modified antibody, to the disk’s surface was demonstrated. [ABSTRACT FROM AUTHOR]

In two-phase nanocomposite magnets, open recoil loops have shown to be sensitive to interphase interfacial conditions and have been often used to characterize the interphase exchange coupling. Typically, the open recoil loops are attributed to the soft phase volume that is decoupled from the hard phase. Our element-specific magnetic measurements on bilayer Sm–Co/Fe exchange-spring magnets reveal that open recoil loops are present not only in the soft Fe layer but also in the hard Sm–Co layer and that the Fe- and Sm-specific remanence curves are similar to each other. The experimental results and micromagnetic modeling reveal that the observed open recoil loops can originate from the anisotropy variations in the hard Sm–Co layer. [ABSTRACT FROM AUTHOR]

This paper reports on the modeling of turbulent reacting flow using the advanced Spectral Line Weighted-sum-of-gray-gases (SLW) method for prediction of the gas thermal radiative transfer. Predictions using the traditional weighted-sum-of-gray-gases radiation submodel are compared to the more advanced SLW treatment of radiation transfer. For the problem considered, the results reveal little difference in the predicted H2O and CO2 concentrations between the two radiation submodels. Further, the predicted furnace mass-averaged exit temperature for both radiation submodels is unchanged. However, there is considerable difference in the predicted radiative and thermal structure in the flame zone, albeit at considerably higher computational expense. The use of the more rigorous SLW model significantly affects the accurate resolution of the local radiative heating and local temperature in the flame region. It is concluded that the more advanced SLW model should be used when seeking to resolve accurately the detailed flame structure. [ABSTRACT FROM AUTHOR]

Charging subscription fees for content distributed through the Internet has emerged as a commonly adopted business model. This has drawn the attention of academics seeking to understand which factors motivate individuals’ willingness to pay for online content. We assert that one important determinant is social influence. For this study, we conceptualized an individual’s social environment as consisting of three levels, the micro, meso, and macro levels. We identified constructs existing at each of these levels—satisfaction, peer group preferences, and reputation, respectively—and examined the influence that they exerted on both willingness to pay and on each other in the context of online video games, specifically, massively multiplayer online games. Our results suggested that all levels of social influence play a role in an individual’s product valuation process. [ABSTRACT FROM AUTHOR]

The article presents a retrospective review of candidiasis in laryngeal biopsies. It mentions that patients who had undergone laryngeal biopsy and used inhaled corticosteroids (ICS). It notes that spacer units were recommended for patients taking ICS to reduce candidiasis rate in the upper aero-digestive tract.

It is demonstrated here that an already ideal exchange-spring magnet can be further improved by intermixing the interface. This is counter-intuitive to the general expectation that optimal exchange- spring magnet behavior requires an ideal, atomically coherent soft-hard interface. Epitaxial Sm- Co/Fe thin-film exchange-spring bilayers are thermally processed, by annealing or high-temperature deposition, to induce interdiffusion. With increasing processing temperature, the hysteresis loop becomes more single-phase-like, yet the magnetization remains fully reversible. The interface is characterized via synchrotron x-ray scattering and electron microscopy elemental mapping. The magnetization behavior is modeled by assuming a graded interface where the material parameters vary continuously. The simulations produce demagnetization curves similar to experimental observations. [ABSTRACT FROM AUTHOR]

Co has been epitaxially grown onto flat and modified Ru(0001) substrates via molecular beam epitaxy at elevated temperature and characterized ex situ with atomic force and magnetic force microscopy. On flat Ru(0001), Co grows into three-dimensional Co islands (dots) of ∼20–900 nm or a flat Co film network with deep holes (antidots) in truncated pyramidal shapes, which randomly distribute on the surface. When the Ru surface morphology is modified via either scratches or e-beam lithography, the dots align along the edges of the surface features (∼4–100 nm deep), and form dot chains, wires, arrays, and dots around lithographic patterns. The dots exhibit in-plane single domains with magnetic easy axis along the edges of these surface features. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Remagnetization processes in a SmCo/NdCo exchange spring system are studied using superconducting quantum interference device magnetometry and magneto-optical imaging. The magneto-optical images reveal that the reversal of the soft NdCo layer and its return to the polarized state at cycling around the exchange bias field occur due to the asymmetric nucleation and growth of twisted-phase domains. The observed peculiarities of the domain-wall kinetics are discussed and a way of tailoring exchange biased systems by regulating the motion of the twisted-phase domains is suggested. [ABSTRACT FROM AUTHOR]

Submicron quasihexagonal Co dots and dot chains have been grown epitaxially on Ru(0001) substrate with molecular beam epitaxy and investigated with magnetic force microscopy. All the dots exhibit in-plane single domains. The magnetization of the dots in a chain prefers to align along the chain direction due to inter-dot magnetostatic interactions. Micromagnetic calculations suggest that the observed single domains are metastable energetically and both vortex and single domain can exist in zero field. The inter-dot magnetostatic coupling, modeled with a dot pair, introduces a uniaxial anisotropy with easy axis along the pair/chain direction. The induced anisotropy field decreases with increasing inter-dot distance and approaches the dipolar limit. [ABSTRACT FROM AUTHOR]

A method for the analysis of temperature and field dependent magnetization data near the Curie temperature T[sub C] is devised, which allows the reliable determination of critical exponents even in strongly inhomogeneous ferromagnets. It is shown, both experimentally and theoretically, that the field-induced broadening of the ferromagnetic phase transition follows a power law with a characteristic critical exponent β-δ where β and δ are the conventional temperature and field dependent critical exponents of the magnetization. Experimental results on inhomogeneous La[sub 2/3]Ca[sub 1/3]MnO[sub 3] films yield critical exponents β = 0.3682 ± 0.0033 and δ = 4.76 ± 0.32, even though the intrinsic T[sub C] distribution width is larger than the field-induced effect. [ABSTRACT FROM AUTHOR]

We have studied the magnetic stability in exchange-bias and exchange-spring systems during repeated reversal of the pinned layer. The samples were prepared by epitaxial sputter deposition. The exchange-biased system consists of a combination of ferromagnetic and antiferromagnetic Fe/Cr superlattices. The exchange-spring system is a bilayer structure made of hard Sm-Co and soft Fe ferromagnetic layers. The magnetic properties were investigated using the magneto-optic Kerr effect during repeated reversal of the soft layer magnetization by field cycling up to 10[sup 7] times. The experimentally observed decay behaviors are discussed in terms of microstructure and spin configuration of the pinning layers. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]