Quantifying the Effect of Non-Larmor Motion of Electrons on the Pressure Tensor

In space plasma, various effects of magnetic reconnection and turbulence cause the electron motion to significantly deviate from their Larmor orbits. Collectively these orbits affect the electron velocity distribution function and lead to the appearance of the "non-gyrotropic" elements in the pressure tensor. Quantification of this effect has important applications in space and laboratory plasma, one of which is tracing the electron diffusion region (EDR) of magnetic reconnection in space observations. Three different measures of agyrotropy of pressure tensor have previously been proposed, namely, A∅ _e , D_ng and Q. The multitude of contradictory measures has caused confusion within the community. We revisit the problem by considering the basic properties an agyrotropy measure should have. We show that A∅ _e , D_ng and Q are all defined based on the sum of the principle minors (i.e. the rotation invariant I ₂) of the pressure tensor. We discuss in detail the problems of I ₂-based measures and explain why they may produce ambiguous and biased results. We introduce a new measure AG constructed based on the determinant of the pressure tensor (i.e. the rotation invariant I ₃) which does not suffer from the problems of I ₂-based measures. We compare AG with other measures in 2 and 3-dimension particle-in-cell magnetic reconnection simulations, and show that AG can effectively trace the EDR of reconnection in both Harris and force-free current sheets. On the other hand, A∅ _e does not show prominent peaks in the EDR and part of the separatrix in the force-free reconnection simulations, demonstrating that A∅ _e does not measure all the non-gyrotropic effects in this case, and is not suitable for studying magnetic reconnection in more general situations other than Harris sheet reconnection.

Osteogenesis-promoting activity of composites SBA-15 mesoporous particles carrying oxytocin in vitro and in vivo

This study analyzes the performance of SBA-15 mesoporous particles carrying oxytocin (OT) in promoting osteogenesis in vitro and in vivo. The SBA-15 particles synthesized in the previous studies (about 30 μm in diameter and containing 10 nm deep pores) were loaded with the drug oxytocin and cultured with human osteosarcoma MG-63 cell line in vitro. The influence of particles on cell proliferation was studied. The level of the osteogenic marker (alkaline phosphatase and type I collagen) was measured. For in vivo studies, the connectivity defects of rabbit skull were prepared, and SBA-15 suspensions were regularly injected at the defect sites. The changes in the defect site calcium salt deposition were measured, and morphological changes were observed by microscopy. The material had to promote effect on osteogenesis-related indicators such as alkaline phosphatase and collagen I in bone sarcoma cell line MG-63. In vivo, the calcium salt deposition in OT/SBA-15 group was significantly higher than in the blank group. SBA-15 carriers appeared to persist in the region of the defect after the injection and release the drugs slowly, thus playing a more distinct role in promoting bone repair of local bone defects. The results showed that SBA-15 particles with OT could slow the release drugs and could help in promoting osteogenesis.

Aortic dissection is associated with reduced polycystin-1 expression, an abnormality that leads to increased ERK phosphorylation in vascular smooth muscle cells

The vascular smooth muscle cell (VSMC) phenotypic switch is a key pathophysiological change in various cardiovascular diseases, such as aortic dissection (AD), with a high morbidity. Polycystin-1 (PC1) is significantly downregulated in the VSMCs of AD patients. PC1 is an integral membrane glycoprotein and kinase that regulates different biological processes, including cell proliferation, apoptosis, and cell polarity. However, the role of PC1 in intracellular signaling pathways remains poorly understood. In this study, PC1 downregulation in VSMCs promoted the expression of SM22α, ACTA2 and calponin 1 (CNN1) proteins. Furthermore, PC1 downregulation in VSMCs upregulated phospho-MEK, phospho-ERK and myc, but did not change phospho-JNK and phospho-p38. These findings suggest that the MEK/ERK/myc signaling pathway is involved in PC1-mediated human VSMC phenotypic switch. Opposite results were observed when an ERK inhibitor was used in VSMCs downregulated by PC1. When the C-terminal domain of PC1 (PC1 C-tail) was overexpressed in VSMCs, the expression levels of phosphor-ERK, myc, SM22α, ACTA2 and CNN1 proteins were downregulated. The group with the overexpressed mutant protein (S4166A) in the PC1 C-tail showed similar results to the group with the downregulated PC1 in VSMCs. These results suggest that the Ser at the 4166 site in PC1 is crucial in the PC1 mediated MEK/ERK/myc signaling pathway, which might be the key pathophysiological cause of AD.

Characterization of Haemonchus contortus P-glycoprotein-16 and its interaction with the macrocyclic lactone anthelmintics

Anthelmintic resistance in veterinary nematodes, including Haemonchus contortus, has become a limitation to maintaining high standards of animal health. Resistance in this parasite, to all drug families including the macrocyclic lactones (MLs) is a serious issue worldwide. Mechanisms of resistance to the MLs appear to be complex and to include the elimination of these compounds by ABC transporter-like proteins present in nematodes. In order to investigate the potential involvement of ABC transporters in ML resistance in H. contortus, we have characterized the functionality of the ABC transporter H. contortus P-glycoprotein-16 (Hco-PGP-16) expressed in mammalian cells. This has included a study of its interaction with different MLs, including the avermectins, abamectin (ABA) and ivermectin (IVM), and the milbemycin, moxidectin (MOX). Hco-PGP-16 transport activity was studied using the fluorophore Rhodamine 123 (Rho 123). Transfected cells expressing Hco-PGP-16 accumulated less than 50% of Rho 123 than control cells, suggesting an active transport of this tracer dye by Hco-PGP-16. The influence of the MLs on the Rho123 transport by Hco-PGP-16 was then investigated. A marked inhibition of Rho123 transport by ABA and IVM was observed. In contrast, MOX showed less effect on inhibition of Rho123 transport by Hco-PGP-16, and the inhibition was not saturable. The difference in the interaction of the avermectins and MOX with Hco-PGP-16 may help explain the slower rate of development of resistance to MOX compared with the avermectins in H. contortus.

Evaluation of collected outcome measures in axial spondyloarthritis in daily-care rheumatology settings: the experience of the RHEVER network

OBJECTIVES

Nowadays, the recommended measures for optimal monitoring of axial Spondyloarthritis (ax-SpA) disease activity are either BASDAI and CRP, or ASDAS-CRP. However, there could be a gap between recommendations and daily practice. We aimed to determine the measures collected by rheumatologists in an ax-SpA follow-up visit, and to determine the impact of a meeting (where rheumatologists reached a consensus on the measures to be collected) on the collection of such measures.

METHODS

A consensual meeting of a local network of 32 rheumatologists proposed, four months later, to report at least the BASDAI score in the medical file of every ax-SpA patient at every follow-up visit. An independent investigator reviewed the medical files of 10 consecutive patients per rheumatologist, seen twice during the year (e.g. before and after the meeting). The most frequently collected measures were assessed, and then, the frequency of collection before and after the meeting was compared.

RESULTS

A total of 456 medical files from 228 patients were reviewed. Treatment (>60%), CRP (51.3%) and total BASDAI (28.5%) were the most reported measures in medical files. Before/After the meeting, the frequencies of collected measures in medical files were 28.5%/51.7%, 51.3%/52.2%, 16.7%/31.6% and 0.9%/6.1% for BASDAI, CRP, BASDAI + CRP and ASDAS, respectively reaching a statistically significance for BASDAI, ASDAS and BASDAI+CRP (p<0.05).

CONCLUSIONS

This study revealed a low rate of systematic report of the recommended outcome measures in ax-SpA. However, it suggests that a consensual meeting involving practicing rheumatologists might be relevant to improve the implementation of such recommendations.

Bidirectional energy cascades and the origin of kinetic Alfvénic and whistler turbulence in the solar wind

The observed steep kinetic scale turbulence spectrum in the solar wind raises the question of how that turbulence originates. Observations of keV energetic electrons during solar quiet time suggest them as a possible source of free energy to drive kinetic turbulence. Using particle-in-cell simulations, we explore how the free energy released by an electron two-stream instability drives Weibel-like electromagnetic waves that excite wave-wave interactions. Consequently, both kinetic Alfvénic and whistler turbulence are excited that evolve through inverse and forward magnetic energy cascades.

Microstructure evolution and photoluminescence in nanocrystalline Mg(x)Zn(1 - x)O thin films

The effects of Mg concentration and annealing temperature on the characteristics of nanocrystalline Mg(x)Zn(1 - x)O thin films (where x = 0-0.4) were studied using electron microscopy and photoluminescence. The films were prepared by a sol-gel method. The solid solubility limit of MgO in ZnO for the sol-gel-derived Mg(x)Zn(1 - x)O films in the present study was determined to be ∼ 20 at.%. Microstructural characterization of the films showed that the wurtzite crystallites decrease in size with increase in Mg concentration up to the solubility limit. Increasing Mg concentration beyond the solubility limit resulted in a decrease in crystallinity of the films. The bandgap energy was found to increase with Mg concentration whereas the linewidth first increased and then decreased when the Mg concentration was increased beyond the solubility limit. Photoluminescence properties have been correlated to the microstructure of the films. A growth mechanism for Mg(x)Zn(1 - x)O nanocrystalline films under the present processing conditions has also been proposed.

Jet deflection by very weak guide fields during magnetic reconnection

Previous 2D simulations of reconnection using a standard model of initially antiparallel magnetic fields have detected electron jets outflowing from the x point into the ion outflow exhausts. Associated with these jets are extended "outer electron diffusion regions." New PIC simulations with an ion to electron mass ratio as large as 1836 (an H(+) plasma) now show that the jets are strongly deflected and the outer electron diffusion region is broken up by a very weak out-of-plane magnetic guide field, even though the diffusion rate itself is unchanged. Jet outflow and deflection are interpreted in terms of electron dynamics and are compared to recent measurements of jets in the presence of a small guide field in Earth's magnetosheath.

Nonlinear development of streaming instabilities in strongly magnetized plasma

The nonlinear development of streaming instabilities in the current layers formed during magnetic reconnection with a guide field is explored. Theory and 3D particle-in-cell simulations reveal two distinct phases. First, the parallel Buneman instability grows and traps low velocity electrons. The remaining electrons then drive two forms of turbulence: the parallel electron-electron two-stream instability and the nearly perpendicular lower-hybrid instability. The high velocity electrons resonate with the turbulence and transfer momentum to the ions and low velocity electrons.

Electron acceleration from contracting magnetic islands during reconnection

A long-standing problem in the study of space and astrophysical plasmas is to explain the production of energetic electrons as magnetic fields 'reconnect' and release energy. In the Earth's magnetosphere, electron energies reach hundreds of thousands of electron volts (refs 1-3), whereas the typical electron energies associated with large-scale reconnection-driven flows are just a few electron volts. Recent observations further suggest that these energetic particles are produced in the region where the magnetic field reconnects. In solar flares, upwards of 50 per cent of the energy released can appear as energetic electrons. Here we show that electrons gain kinetic energy by reflecting from the ends of the contracting 'magnetic islands' that form as reconnection proceeds. The mechanism is analogous to the increase of energy of a ball reflecting between two converging walls--the ball gains energy with each bounce. The repetitive interaction of electrons with many islands allows large numbers to be efficiently accelerated to high energy. The back pressure of the energetic electrons throttles reconnection so that the electron energy gain is a large fraction of the released magnetic energy. The resultant energy spectra of electrons take the form of power laws with spectral indices that match the magnetospheric observations.

Effects of huang qi wu wu decoction on plasma proteins in 70 cases of chronic pulmonary heart disease

Simple immune agar diffusion test was used to assay the contents of 12 plasma proteins in 70 cases of chronic pulmonary heart disease treated by Huang Qi Wu Wu Decoction ([symbol: see text]), with the other 70 cases who were not given Huang Qi Wu Wu Decoction as the control group. The total clinical effective rate in the treatment group was 90.0%, while that in the control group was 75.7%, with a statistically significant difference between the two groups (P < 0.05). In the treatment group, the levels of prealbumin, transferrin and fibronectin elevated obviously after treatment, and the contents of C-reactive protein, ceruloplasmin, haptoglobin, alpha 1-antitrypsin and alpha 1-acid glycoprotein decreased markedly (P < 0.01). In the control group, only the levels of ceruloplasmin and C-reactive protein decreased significantly (P < 0.05). It is shown that Huang Qi Wu Wu Decoction may enhance the therapeutic effects for pulmonary heart disease, regulate the metabolism of plasma proteins, and improve the life quality of the patients.

Decentralized optimal traffic engineering in the internet

Distributed optimal traffic engineering in the presence of multiple paths has been found to be a difficult problem to solve. In this paper, we introduce a new approach in an attempt to tackle this problem. This approach has its basis in nonlinear control theory. More precisely, it relies on the concept of Sliding Modes. We develop a family of control laws, each of them having the property that the steady-state network resource allocation yields the maximum of the given utility function, subject to the network resource constraints. These control laws not only allow each ingress node to independently adjust its traffic sending rate but also provide a scheme for optimal traffic load redistribution among multiple paths. The only nonlocal information needed is binary feedback from each congested node in the path. Moreover, the algorithms presented are applicable to a large class of utility functions, namely, utility functions that can be expressed as the sum of concave functions of the sending rates. We show that the technique can be applied not only to rate adaptive traffic with multiple paths, but also to assured service traffic with multiple paths. Preliminary case studies show that this technique is potentially very useful for optimal traffic engineering in a multiple-class-of-service and multiple-path enabled Internet, e.g., differentiated services enabled multi-protocol label switching networks.

Cryptococcal pneumonia simulating chronic eosinophilic pneumonia

We report two cases of cryptococcal pneumonia in which the roentgenographic picture closely mimicked that for chronic eosinophilic pneumonia. Caution in use of corticosteriods based on this roentgenographic pattern is stressed.

Relationship between plantar pressure distribution under the foot and insole comfort

In this paper, four pairs of insoles with different comfort characteristics were used to investigate the relationship between the pressure distribution under the foot and running shoe comfort. Fourteen male subjects were tested in four insole conditions by walking and running on a treadmill. The pressure at the plantar surface of the foot was measured by using an EMED pressure-measuring insole. For walking there were significantly higher pressures and forces in the midfoot area and significantly lower pressures in the medial forefoot and hallux area by wearing the most comfortable insole compared with wearing the least comfortable insole. The shift of the pressure from forefoot to midfoot for the most comfortable insole provided an even distribution of the pressure at the plantar surface of the foot. The results also demonstrated that the path of centre of force at the plantar surface of the foot moved to the lateral aspect of the foot for the most comfortable insole. For running, only the pressure in the medial forefoot area was found significantly lower for the most comfortable insole than for the least comfortable insole. The results of this study indicated that the pressure distribution between the plantar surface of the foot and the shoe could detect the change of shoe comfort. Thus it is a suggestion that pressure measurement may be related to understand factors important for shoe comfort. Comfort of sport shoes is important for the appropriate execution of sport activities. Additionally, comfort may influence fatigue and possibly the development of injuries. The quantification of comfort of sport shoes and the understanding of mechanical and/or biological functions related to it may be enhanced with the use of pressure measurements between the plantar surface of the foot and the shoe sole.