[1] A three dimensional ray tracing of fast magnetosonic (MS) waves is first performed by using a global core density model and a field-aligned density model. Simulating results show that MS waves are primarily confined within a few degrees of the geomagnetic equator due to magnetospheric reflection. MS waves originating from different L-shells on the dayside can propagate either into or out of the plasmasphere through the plasmapause. In particular, MS waves can propagate eastward (later MLT) or westward (earlier MLT) over a broad region of MLT. The current results further reveal a variety of propagation characteristics, particularly important for the MLT distribution of MS waves.

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Background Malnutrition is a common and critical problem that influences outcome in cancer patients. Body composition reflects a patient’s metabolic profile and physiologic reserves, which might be the true determinant of prognosis. In the present study, which aimed to identify valuable new prognostic indicators, we investigated the association between computed tomography–quantified body composition and short-term outcomes after gastrectomy for gastric cancer.MethodsSkeletal muscle index, mean muscle attenuation, and ratio of visceral-to-subcutaneous adipose tissue area (vsr) were calculated from preoperative computed tomography images. Low skeletal muscle index, low mean muscle attenuation, and high vsr were respectively termed “sarcopenia,” “myosteatosis,” and “visceral obesity.” The association of body composition with postoperative complications and serum markers of nutrition and inflammation after radical gastrectomy were analyzed.ResultsThe overall complication rate was significantly higher in the sarcopenia (62.5% vs. 27.3%, p = 0.001) and myosteatosis groups (38.2% vs. 4%, p = 0.002). Patients with visceral obesity had a higher incidence of inflammatory complications (20.3% vs. 6.5%, p = 0.01). Multivariate logistic regression analysis demonstrated that sarcopenia (p = 0.013), myosteatosis (p = 0.017), and low serum retinol-binding protein (p = 0.019) were independent risk factors for overall complications. Compared with control subjects, patients with sarcopenia had lower postoperative levels of serum retinol-binding protein (p = 0.007), and patients with visceral obesity had higher levels of C-reactive protein (p = 0.026).Conclusions Sarcopenia, myosteatosis, and visceral obesity were significantly associated with increased rates of postoperative complications and affected the postoperative nutrition and inflammation status of patients with gastric cancer.

[1] We report correlated observation of enhanced electromagnetic ion cyclotron (EMIC) waves and dynamic evolution of ring current proton flux collected by Cluster satellite near the location L = 4.5 during March 26-27, 2003, a nonstorm period (D st > À10). Energetic (5-30 keV) proton fluxes are found to drop rapidly (e.g., a half hour) at lower pitch angles, corresponding to intensified EMIC wave activities. By adopting a Gaussian fit to the observed spectra of EMIC waves, we present two-dimensional (2D) numerical simulations which demonstrate that EMIC wave can yield such decrements in proton flux within 30 minutes, consistent with the observational data. The current result provides a further understanding of ring current dynamics driven by wave-particle interaction under different geomagnetic activities.

[1] Simultaneous observations of enhanced fast magnetosonic (MS) waves and distinct proton ring distributions collected by Cluster satellite near the location L = 4-5 on 28 May 2005 are analyzed to study instability of MS waves. A sum of subtracted bi-Maxwellian components is utilized to fit the observed proton (2-10 keV) ring distributions. A ray-tracing simulation is performed to calculate the local growth rate and path-integrated gain of MS waves. Peak growth rates are found to occur at the multiples of proton gyrofrequency mainly in the range 70-120 Hz, and wave gain lies in 40-80 dB, comparable to the observation. Moreover, MS waves primarily locate within a few degrees of the geomagnetic equator and propagate either into or out of the plasmasphere through the plasmapause. The current results provide observational support for instability of fast magnetosonic waves generated by the proton ring distribution.

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Background: Despite the presence of glucagon-like peptide-1 receptor (GLP-1R) in kidney tissues, its direct effect on diabetic nephropathy remains unclear. The transforming growth factor-β₁ (TGF-β₁) and the connective tissue growth factor (CTGF) both induce extracellular matrix accumulation and persistent fibrosis in the glomerular mesangium of patients with diabetic nephropathy. Objective: Herein, we demonstrate that a GLP-1R agonist, exendin-4, exerts renoprotective effects through its influence on TGF-β₁ and CTGF in human mesangial cells (HMCs), cultured in a high glucose medium. Method: HMCs, cultured in a high glucose medium, were used for the current study. The direct effect of exendin-4 on TGF-β₁ and CTGF expression was confirmed in HMCs. MDL-12330A (a specific adenylate cyclase inhibitor) and PKI14-22 (a protein kinase A inhibitor) were used to examine the role of the cAMP signaling pathway in exendin’s anti-fibrosis action. Results: The findings showed that exendin-4 inhibited the proliferation of HMCs, and upregulated the expression of TGF-β₁ and CTGF, induced by high glucose. The effect of exendin-4 is largely dependent on the activation of adenylate cyclase. Conclusion: This study provides new evidence that GLP-1 acts as an antifibrotic agent in HMCs.

[1] A cold electron heating event associated with electromagnetic ion cyclotron (EMIC) waves is observed and modeled. The observational data of particles and waves are collected by the Thermal Emission Imaging System spacecraft at magnetic local time 17.0-17.2. During this event, intense He + band EMIC waves with the peak frequency 0.25 Hz are excited, corresponding to the observed phase space density (PSD) of distinct anisotropic ions. Meanwhile, substantial enhancements in energy flux of cold (1-10 eV) electrons are observed in the same period. The energy flux of electrons below 10 eV is increased by several to tens of times. We use a sum of kappa distribution components to fit the observed ion PSD and then calculate the wave growth rate driven by the anisotropic hot protons. The calculated result is in good agreement with the in situ observation. Then, we investigate whether the excited EMIC waves can transfer energy to cold electrons by Landau resonant absorption and yield electron heating. Using the typical Maxwellian distribution for cold electrons, we evaluate the wave damping rates resulted from the cold electrons in gyroresonance with EMIC waves. The simulating results show that the strong wave growth region in the He + band induced by anisotropic ions corresponds to the strong wave damping region driven by cold electrons. Moreover, cold electrons can be heated efficiently at large wave normal angles. The current results provide a direct observational evidence for EMIC-driven cold electron heating-a potential mechanism responsible for stable auroral red arc.