Formation of the mass density peak at the magnetospheric equator triggered by EMIC waves

We report a simultaneous observation of two band electromagnetic ion cyclotron(EMIC)waves and toroidal Alfvén waves by the Van Allen Probe mission.Through wave frequency analyses,the mass densityρis found to be locally peaked at the magnetic equator.Perpendicular fluxes of ions(<100 eV)increase simultaneously with the appearances of EMIC waves,indicating a heating of these ions by EMIC waves.In addition,the measured ion distributions also support the equatorial peak formation,which accords with the result of the frequency analyses.The formation of local mass density peaks at the equator should be due to enhancements of equatorial ion concentrations,which are triggered by EMIC waves’perpendicular heating on low energy ions.

Clinical correlations between chronic hepatitis C infection and decreasing bone mass density after treatment with interferon-alpha

Objective: To compare the bone mass density in chronic hepatitis patients before and after interferon-a treatment.Methods: A total of 70 patients with chronic hepatitis C were treated with interferon-a and were evaluated. The treatment dosage was three million IU three times a week for one year. All the patients underwent bone mass density detection at lumbar spine and femoral neck before and after the interferon-a treatment. All the necessary information such as age,sex, and laboratory test, history of occurrence of fractures, lifestyle, and menopause status was collected by interviewers face-to-face from participants at the research visit. Smoking was categorized by whether participants were nonsmokers or smokers. Menopause was designated if there had been complete cessation of menses for more than 12 months. All statistical analyses were performed by SPSS version 14(SPSS, Inc., Chicago, IL, USA).Results: Among 70 patients, 52% were male, 48% were female and the mean age was(57.0 ± 9.6) years(range: 24–79). Twenty-nine percent of the patients had a history of smoking. The mean body mass index was(24.4 ± 3.6) kg/m^2(range: 18.4–35.3). Of the70 cases, 21 had high fibrosis-4. The prevalence of overall fracture history was 2.9%(two patients).Conclusions: Chronic hepatitis C virus infection did increase the risk of development of metabolic bone disease in this cohort. Indeed, greater reduction of bone mass density occurs in advanced liver fibrosis. The bone loss in earlier stages of chronic hepatitis C infection is likely to result from increased bone reduction rather than decreased bone formation. Overall, these observations suggest an important role for chronic hepatitis C virus infection in increased bone turnover in osteodystrophy pathogenesis.

Thermospheric mass density measurement from precise orbit ephemeris

Atmospheric drag, which can be inferred from orbit information of low-Earth orbiting （LEO） satellites, provides a direct means of measuring mass density. The temporal resolution of derived mass density could be in the range from minutes to days, depending on the pre- cision of the satellite orbit data. This paper presents two methods potentially being able to estimate thermosphere mass density from precise obit ephemeris with high temporal resolution. One method is based on the drag perturbation equation of the semi-major axis and the temporal resolution of retrieved density could be ~lB0 s for CHAMP satellite. Another method generates corrections to densities computed from a baseline density model through a Kalman filter orbit drag coefficient determination （KFOD） process and the temporal resolution of derived density could be as high as 30 s for CHAMP satellite. The densities estimated from these two methods are compared with densities obtained from accelerometer data of CHAMP satellite. When the accelerometer data based densities are used as reference values, the mean relative accuracy of the densities derived from precision orbit data using the two methods is within approximately 10%. An application of the derived densities shows that the derived densities can reduce orbit predication errors.

Valence band structure and density of states effective mass model of biaxial tensile strained silicon based on k·p theory

After constructing a stress and strain model, the valence bands of in-plane biaxial tensile strained Si is calculated by k·p method. In the paper we calculate the accurate anisotropy valance bands and the splitting energy between light and heavy hole bands. The results show that the valance bands are highly distorted, and the anisotropy is more obvious. To obtain the density of states （DOS） effective mass, which is a very important parameter for device modeling, a DOS effective mass model of biaxial tensile strained Si is constructed based on the valance band calculation. This model can be directly used in the device model of metal-oxide semiconductor field effect transistor （MOSFET）. It also a provides valuable reference for biaxial tensile strained silicon MOSFET design.

Preliminarily study of Saturn’s upper atmosphere density by observing Cassini plunging via China’s deep space station

When the Cassini spacecraft finally plunged into the Saturnian atmosphere on 2017 September15,China’s deep space telescope pointed to Saturn to observe Cassini and study the Saturnian upper neutral atmosphere.In this first Chinese Saturnian radio science experiment,X band Doppler velocity radio science data between the deep space telescope and the Cassini spacecraft were obtained.After removing Saturnian and solar gravity effects,Earth rotation effect,the remaining Saturnian atmosphere drag information was retrieved in the Cassini final plunge progress.Saturn’s upper neutral atmosphere mass density profile is approximately estimated based on atmosphere mass density derived principally by real orbit measurement data.Saturn’s upper neutral atmosphere mass density from 76000 km to 1400 km is estimated from the orbit measurement data,the mass density results are about from 1.4×10^-15 kg cm^-3 to 2.5×10^-14 kg cm^-3.

An acoustic bending waveguide designed by anisotropic density-near-zero metamaterial

Anisotropic metamaterial with only one component of the mass density tensor near zero （ADNZ） is proposed to control the sound wave propagation. We find that such an anisotropic metamaterial can be used to realize perfect bending waveguides. According to a coordinate transformation, the surface waves on the input and output interfaces of the ADNZ metamaterial induces the sound energy flow to be redistributed and match smoothly with the propagating modes inside the metamaterial waveguide. According to the theory of bending waveguide, we realize the ＂T＂-type sound shunting and convergence, as well as acoustic channel selection by embedding small-sized defects. Numerical calculations are performed to confirm the above effects.

Effect of reactive surface area of minerals on mineralization trapping of CO_2 in saline aquifers

The reactive surface area, an important parameter controlling mineral reactions, affects the amount of mineralization trapping of CO2 which affects the long-term CO2 storage. The effect of the reactive surface area on the mineralization trapping of CO2 was numerically simulated for CO2 storage in saline aquifers. Three kinds of minerals, including anorthite, calcite and kaolinite, are involved in the mineral reactions. This paper models the relationship between the specific surface area and the grain diameter of anorthite based on experimental data from literature （Brantley and Mellott, 2000）. When the reactive surface areas of anorthite and calcite decrease from 838 to 83.8 m^2/m^3, the percentage of mineralization trapping of CO： after 500 years decreases from 11.8% to 0.65%. The amount of dissolved anorthite and the amounts of precipitated kaolinite and calcite decrease significantly when the reactive surface areas ofanorthite and calcite decrease from 838 to 83.8 m2/m3. Calcite is initially dissolved in the brine and then precipitates during the geochemical reactions between CO2-H20 and the minerals. Different reactive surface areas of anorthite and calcite lead to different times from dissolution to precipitation. The pH of the brine decreases with decreasing reactive surface areas of anorthite and calcite which influences the acidity of the saline aquifer. The gas saturation between the upper and lower parts of the saline aquifer increases with decreasing reactive surface areas of anorthite and calcite. The mass density distribution of brine solution shows that the CO2^＋brine solution region increases with decreasing reactive surface areas ofanorthite and calcite.

Numerical simulation of carbon arc discharge for graphene synthesis without catalyst

In this study, graphene sheets are prepared under a hydrogen atmosphere without a catalyst, and the growth mechanism of graphene by direct current arc discharge is investigated experimentally and numerically. The size and layer numbers of graphene sheets increase with the arc current.Distributions of temperature, velocity, and mass fraction of carbon are obtained through numerical simulations. A high current corresponds to a high saturation temperature, evaporation rate, and mass density of carbon clusters. When the carbon vapor is saturated, the saturation temperatures are 3274.9, 3313.9, and 3363.6 K, and the mass densities are 6.4×1022,8.42×1022, and 1.23×1023 m-3 under currents of 150, 200, and 250 A, respectively. A hydrogen-induced marginal growth model is used to explain the growth mechanism. Under a high current, the condensation coefficient and van der Waals force increase owing to the higher saturation temperature and mass density of carbon clusters, which is consistent with experimental results.

How the Redshift of Gravitons Explains Dark Matter and Dark Energy

The theory that gravitons lose energy by way of gravitational redshift while traveling in a gravitational field is applied to the expansion of the universe and to spiral and dwarf galaxy rotation curves using General Relativity. This is a graviton self interaction model which derives an expansion equation which is identical in form to the standard Lambda Cold Dark Matter model. In the domain of galaxies, spiral and dwarf galaxy rotation curves are matched using only baryonic mass. Thus, the requirement for dark matter and dark energy in the universe is replaced by this paradigm.

Light Speed Expansion and Rotation of a Very Dark Machian Universe Having Internal Acceleration

We present a Machian model of Quantum Cosmology with full dark matter and light speed expansion and rotation. During galaxy formation and evolution, fraction of dark matter transforms to visible matter with a relation of the form, m_vis = constant * (m_dark)2/3. Using this relation and replacing MOND’s “critical acceleration” with “current cosmic maximum angular acceleration”, galactic flat rotation speed range of (50 to 500) km/sec can be fitted well. Estimated flat rotation speeds of DD168, Milky Way and UGC12591 are 49.96 km/sec, 199.66 km/sec and 521.75 km/sec respectively. Based on these striking coincidences, it is possible to say that, MOND’s approach is implicitly connected with cosmological estimation of 95% invisible matter. With reference to SPARC data for flat rotation speeds and current cosmic maximum angular acceleration, galactic total mass can be estimated. Considering galactic total mass, galactic visible mass and dark mass can be estimated. Proceeding further, galactic working radii, angular velocity and visible matter density can be estimated. Estimated Milky Way’s effective radius is 293 kpc. Even though, this model is free from “big bang”, “inflation”, “dark energy”, “flatness” and “red shift” issues, at 2.722 K, estimated present Hubble parameter is 66.24 km/sec/Mpc, cosmic radius is 146.3 times of the Hubble radius, angular velocity is 146.3 times lower than the Hubble parameter and cosmic age is 146.3 times of the Hubble age. With future observations and advanced telescopes, it may be possible to see far distant galaxies and very old stars far beyond the current observable cosmic radius.

Giant Magnetostrictive Material Loudspeaker System Acoustic Radiation Simulation

An infinite panel model of giant magnetostrictive material loudspeaker system （GMMLS） is proposed by making use of finite element method（FEM）. Bending wave eigenfunction is introduced to describe the acoustic radiation condition of the panel. Far-field response in different conditions is calculated by changing the mass surface density. Conclusion is obtained by analyzing the curves simulated, that panel which has larger mass surface density can hardly generate far-field acoustic radiation for lower frequency, while the panel has smaller mass surface density generates far-field acoustic radiation for lower frequency evenly and stronger.

Impact of utility-scale solar photovoltaic array on the aeolian sediment transport in Hobq Desert, China

Deserts are ideal places to develop ground-mounted large-scale solar photovoltaic (PV) powerstation. Unfortunately, solar energy production, operation, and maintenance are affected bygeomorphological changes caused by surface erosion that may occur after the construction of the solar PVpower station. In order to avoid damage to a solar PV power station in sandy areas, it is necessary toinvestigate the characteristics of wind-sand movement under the interference of solar PV array. The studywas undertaken by measuring sediment transport of different wind directions above shifting dunes andthree observation sites around the PV panels in the Hobq Desert, China. The results showed that the twoparameterexponential function provides better fit for the measured flux density profiles to the near-surfaceof solar PV array. However, the saltation height of sand particles changes with the intersection anglebetween the solar PV array and wind direction exceed 45°. The sediment transport rate above shifting duneswas always the greatest, while that around the test PV panels varied accordingly to the wind direction.Moreover, the aeolian sediment transport on the solar PV array was significantly affected by wind direction.The value of sand inhibition rate ranged from 35.46% to 88.51% at different wind directions. When theintersection angle exceeds 45°, the mean value of sediment transport rate above the solar PV array reducesto 82.58% compared with the shifting dunes. The results of our study expand our understanding of theformation and evolution of aeolian geomorphology at the solar PV footprint. This will facilitate the designand control engineering plans for solar PV array in sandy areas that operate according to the wind regime.

As Regards the Speed in a Medium of the Electromagnetic Radiation Field

The velocity of the electromagnetic radiation in a perfect dielectric, containing no charges and no conduction currents, is explored and determined on making use of the Lorentz transformations. Besides the idealised blackbody radiation, whose vacuum propagation velocity is the universal constant c, being this value independent of the observer, there is another behaviour of electromagnetic radiation, we call inertial radiation, which is characterized by an electromagnetic inertial density , and therefore, it happens to be described by a time-like Poynting four-vector field which propagates with velocity . is found to be a relativistic invariant expressible in terms of the relativistic invariants of the electromagnetic field. It is shown that there is a rest frame, where the Poynting vector is equal to zero. Both phase and group velocities of the electromagnetic radiation are evaluated. The wave and eikonal equations for the dynamics of the radiation field are formulated.

Salmon calcitonin in prevention of osteoporosis in maintenance dialysis patients

Background Renal osteodystrophy is one of the commonest complications of chronic renal failure. It may have a severe impact on the quality of life of patients on maintenance dialysis therapy. Besides post-menopausal women and elderly people, the dialysis patients are another high risk group. But at present, there is no research on how to prevent osteoporosis in maintenance dialysis patients. This study was conducted to observe the bone density of maintenance dialysis patients and to evaluate the clinical outcomes and safety of different administration dosage of salmon calcitonin to prevent osteoporosis in maintenance dialysis patients. Methods One hundred and forty-eight patients on maintenance dialysis were involved in the 12-month, randomized, controlled trial. Fifty patients （experiment I group） received subcutaneous injection of salmon calcitonin （50 U） three times a week for 12 months. Fifty patients （experiment II group） received subcutaneous injection of salmon calcitonin （100 U） three times a week for 12 months. At the same time, both of them received oral calcium carbonate 1500 mg tid and rocaltrol 0.25 pg qn for 12 months. The control group only received oral calcium carbonate 1500 mg tid and rocaltrol 0.25 μg qn for 12 months. The levels of bone mass density （BMD） of the lumbar spine and femoral neck, serum intact parathyroid hormone （iPTH）, osteocalcin （OC）, calcium, phosphorus, alkaline phosphatase （ALP） were assessed at baseline and then again after 3, 6 and 12 months of treatment. Results The values of BMD at the lumbar spine and femoral neck before the treatment were not significantly different from those 3, 6, and 12 months after the treatment in trial groups I and II （all P 〉0.05） and there were no significant differences in the BMD values at different time points between trial groups I and II. In the control group, the BMD values at the lumbar spine and femoral neck 3, 6, and 12 months after the beginning of trial were significantly lower than those before the trial, and significantly lower than the corresponding values of trial groups I and II （all P 〈0.05）. The serum OC 3, 6, and 12 months after the treatment was significantly lower than that before the experiment （all P 〈0.05） in the control group. However, there was no significant difference in the value of serum OC before and 3, 6, and 12 months after the treatment in trial groups land II （all P 〉0.05）. Conclusions The dose of salmon calcitonin 50 U three times a week plus calcium carbonate and active vitamin D can effectively preserve the BMD and prevent bone loss in maintenance dialysis patients, and it is well tolerated by patients on maintenance dialysis.

Size-dependent dissociation of small cobalt clusters on ultrathin NaCI films

Mass-selected anionic cobalt clusters of two different sizes （Co2 and Co13） were deposited onto ultrathin NaC1 films grown on an Au（111） substrate. Using scanning tunneling microscopy experiments and density functional theory simulations, we show that the deposited Co2 cluster dissociates and that the resulting Co atoms dope the NaCI surface by substituting Na ions. In contrast, the larger Co13 cluster does not dissociate and remains stable on top of the NaC1 film. The size- dependent fragmentation of clusters is an important aspect in the understanding of the chemical interaction between size-selected small aggregates of atoms and supporting surfaces.