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Background and Aims: Incretin hormones glucagon-like peptide (GLP)-1 and glucose-dependent insulinotropic polypeptide (GIP) are affected early on in the pathogenesis of metabolic syndrome and type 2 diabetes. Epidemiologic studies consistently link high fructose consumption to insulin resistance but whether fructose consumption impairs the incretin response remains unknown.Methods and Results: As many as 66 obese (BMI 26-40 kg/m2) male subjects consumed fructose-sweetened beverages containing 75 g fructose/day for 12 weeks while continuing their usual lifestyle. Glucose, insulin, GLP-1 and GIP were measured during oral glucose tolerance test (OGTT) and triglycerides (TG), GLP-1, GIP and PYY during a mixed meal test before and after fructose intervention. Fructose intervention did not worsen glucose and insulin responses during OGTT, and GLP-1 and GIP responses during OGTT and fat-rich meal were unchanged. Postprandial TG response increased significantly, p = 0.004, and we observed small but significant increases in weight and liver fat content, but not in visceral or subcutaneous fat depots. However, even the subgroups who gained weight or liver fat during fructose intervention did not worsen their glucose, insulin, GLP-1 or PYY responses. A minor increase in GIP response during OGTT occurred in subjects who gained liver fat (p = 0.049).Conclusion: In obese males with features of metabolic syndrome, 12 weeks fructose intervention 75 g/day did not change glucose, insulin, GLP-1 or GIP responses during OGTT or GLP-1, GIP or PYY responses during a mixed meal. Therefore, fructose intake, even accompanied with mild weight gain, increases in liver fat and worsening of postprandial TG profile, does not impair glucose tolerance or gut incretin response to oral glucose or mixed meal challenge. [ABSTRACT FROM AUTHOR]

Abstract: We present theoretical and numerical studies of nonlinear interactions between a short, intense laser-beam and a plasma containing hot electrons. Such plasmas are frequently observed in fast-ignition experiments where electrons are heated by intense laser beams. Due to the combined effects of relativistic electron mass increase and relativistic ponderomotive force of the intense laser fields, there appear localized laser pulses in association with large amplitude localized positive potentials. The latter can trap and accelerate electrons to ultra-relativistic energies. This is demonstrated by means of computer simulations of the time-dependent nonlinear electromagnetic wave equation, supplemented by the Vlasov and Poisson equations. [Copyright &y& Elsevier]

Abstract: Due to the gravitational force, clouds of dust and gas in the interstellar medium can contract and form stars and planet systems. Here we show that if the dust grains are electrically charged then the self-gravitation can be balanced by the “electrostatic pressure” and the collapse can be halted. In this case, the dust cloud may form soft dust planets, having the weight of a small moon or satellite, but a radius larger than of our Sun. There exist a critical mass beyond which the dust cloud collapses and forms a solid planet. We here present a simple model for the dynamics and equilibrium of self-gravitating dust clouds and apply the model to typical parameters for dust in molecular clouds and in the interstellar medium. [Copyright &y& Elsevier]

Abstract: Recent satellite observations reveal localized whistler wavepackets that are correlated with density and magnetic field perturbations. This can be understood in terms of nonlinear interactions between three-dimensional whistlers and the background plasma density and magnetic field. The relevant equations for such nonlinear wave couplings are presented. Simulation studies of nonlinearly coupled electron whistlers and low-frequency magnetosonic perturbations reveal interesting features of whistler pulse compression and diffraction as well as the formation of magnetosonic wedges behind a three-dimensional (3D) localized whistler pulse. The results are useful for understanding the nonlinear propagation of whistlers in space and laboratory plasmas. We suggest that new experiments should be conducted to verify the 3D nonlinear wave phenomena involving electron whistlers and magnetosonic perturbations that we have described in here. [Copyright &y& Elsevier]

Abstract: We present a theory for finite-amplitude relativistic electron holes, which are localized Bernstein–Greene–Kruskal (BGK) solutions characterized by a trapped population of electrons moving with the electron hole. We find that the relativistic effects can drastically modify the electron hole, which becomes wider and is associated with a larger electrostatic potential, accelerating the electrons to highly relativistic energies. The theory has relevance for understanding the properties of strong localized electric fields in high-energy laser-plasma experiments and in supernovae remnants, where relativistic electron holes are a natural product of streaming instabilities. [Copyright &y& Elsevier]

Abstract: Dispersion properties of low-frequency (in comparison with the ion gyrofrequency) compressional electromagnetic waves in a nonuniform dusty magnetoplasma are presented. By using the plasma hydrodynamic equations together with the Faraday and Ampère laws, we derive a new dispersion relation. The latter is analyzed to show the relationship between various wave modes in dusty plasmas. The results should be useful in understanding the features of compressional electromagnetic waves in nonuniform astrophysical and laboratory dusty magnetoplasmas. [Copyright &y& Elsevier]

Abstract: A prospective study of normoalbuminuric diabetic patients was performed between 1997 and 2002 on 4097 type 1 and 6513 type 2 diabetic patients from the Swedish National Diabetes Register (NDR); mean study period, 4.6 years. The strongest independent baseline risk factors for the development of microalbuminuria (20–200μg/min) were elevated HbA1c and diabetes duration in both types 1 and 2 diabetic patients. Other risk factors were high BMI, elevated systolic and diastolic BP in type 2 patients, and antihypertensive therapy in type 1 patients. A subsequent larger cross-sectional study in 2002 showed that established microalbuminuria was independently associated with HbA1c, diabetes duration, systolic BP, BMI, smoking and triglycerides in types 1 and 2 diabetic patients, and also with HDL-cholesterol in type 2 patients. Relatively few types 1 and 2 patients with microalbuminuria achieved treatment targets of HbA1c < 6.5% (21–48%), BP < 130/85mmHg (33–13%), cholesterol < 5mmol/l (48–46%), triglycerides < 1.7mmol/l (83–48%) and BMI < 25kg/m2 (50–18%), respectively. In conclusion, high HbA1c, BP and BMI were independent risk factors for the development of microalbuminuria in types 1 and 2 diabetic patients. These risk factors as well as triglycerides, HDL-cholesterol and smoking were independently associated with established microalbuminuria. Treatment targets were achieved by a relatively few patients with microalbuminuria. [Copyright &y& Elsevier]

In quantum electrodynamics, photon–photon scattering gives rise to self-interaction terms in Maxwell''s equations. The effect will be non-zero for electromagnetic waves trapped between regions of conducting material, such as two plasma layers. It is shown numerically that this trapping in conjunction with photon–photon scattering can yield self-compression of electromagnetic waves. We discuss the relevance of our results. [Copyright &y& Elsevier]

AIM: To estimate hazard ratio (HR) of first incident fatal/non-fatal cardiovascular diseases (CVD) in female/male type 2 diabetic patients, with tight versus adverse control of HbA1c and blood pressure (BP) at baseline, age 30-70 years, no baseline CVD, followed for mean 5.7 years. METHODS: 2593 patients with tight control of HbA1c <7.5% and BP < or = 140/90 mmHg (median 6.5%/130/80 mmHg), and 2160 patients with adverse control 7.5-9.0%/141-190/91-110 mmHg (median 8.1%/155/85 mmHg). RESULTS: The hazard ratio (HR) for CVD with tight/adverse control was 0.67 (0.55-0.80; p<0.001), adjusting for age, sex, duration, hypoglycaemic treatment, smoking, BMI, lipid-lowering drugs, antihypertensive drugs, microalbuminuria. Adjusted HR for myocardial infarction, coronary heart disease, stroke and total mortality were 0.72 (0.56-0.92; p=0.01), 0.69 (0.55-0.86; p<0.001), 0.62 (0.45-0.84; p<0.001), 1.00 (0.72-1.39). The partial population-attributable risk percent for myocardial infarction, stroke and CVD was 23%, 33%, 29% if adverse HbA1c/BP control could be avoided, while 43%, 38%, 39% with overweight and smoking also avoided. Baseline lower BMI and absence of microalbuminuria were associated with tight control. CONCLUSION: Median difference of HbA1c/BP 1.6%/25/5 mmHg between tight and adverse control considerably reduced the risk of cardiovascular diseases. The findings call for a multi-factorial approach to improve HbA1c, BP, obesity, smoking, and microalbuminuria. [ABSTRACT FROM AUTHOR]