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The dependence of the response of the kidneys in terms of hemodynamics and tubular function to somatosensory stimulation on the renal nerve is investigated in anesthetized rats with intact or resected renal nerves stimulated with subcutaneous injection of capsaicin. The pressor and antinatriuresis response was abolished in subjects with resected renal nerves.

The magnitude and pattern of the renal sympathetic nerve activity responses and the functional correlates were compared to two distinct cases in hypertensive and normotensive rats by subcutaneously treating the rodents with capsaicin. Both the exposure to poisonous fumes and the administration of capsaicin had caused the stimulation of the somatosensory system, which led to the increase in blood pressure. The changes in renal hemodynamics and decreased water and sodium excretion were all found to be minimal.

This study examined the effect of leptin and orexin‐A on autonomic baroreflex control in conscious Wistar rats exposed to high‐fat (45% fat) or normal (3.4%) diet for 4 weeks. Renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP) and heart rate (HR) were monitored during the generation of baroreflex gain curves and acute volume expansion (VEP). Intracerebroventricular (ICV) leptin (1 μg/min) increased RSNA in the normal diet group (0.31 ± 0.04 vs 0.23 ± 0.03 mV/s) and MAP in the high‐fat diet group (115 ± 5 vs 105 ± 5 mm Hg, P <.05). Orexin‐A (50 ng/min) increased RSNA, HR and MAP in the high‐fat diet group (0.26 ± 0.03 vs 0.22 ± 0.02 mV/s, 454 ± 8 vs 417 ± 12 beats/min, 117 ± 1 vs 108 ± 1 mm Hg) and the normal diet group (0.18 ± 0.05 vs 0.17 ± 0.05 mV/s, 465 ± 10 vs 426 ± 6 beats/min, 116 ± 2 vs 104 ± 3 mm Hg). Baroreflex sensitivity for RSNA was increased during ICV leptin by 50% in the normal diet group, compared to 14% in the high‐fat diet group (P <.05). Similarly, orexin‐A increased baroreflex sensitivity by 56% and 50% in the high‐fat and normal diet groups, respectively (all P <.05). During ICV saline, VEP decreased RSNA by 31 ± 5% (P <.05) after 10 minutes and the magnitude of this response was blunted during ICV infusion of leptin (17 ± 2%, P <.05) but not orexin‐A in the normal diet group. RSNA response to VEP was not changed during ICV leptin or orexin‐A in the high‐fat diet group. These findings indicate possible central roles for leptin and orexin‐A in modulating the baroreflexes under normal or increased fat intake in conscious rats and potential therapeutic approaches for obesity associated hypertension. [ABSTRACT FROM AUTHOR]

Recovering sparse signals from compressed measurements has received much attention in recent years. Considering that measurement errors always exist, an improved orthogonal matching pursuit (OMP) method which is called Searching Forward OMP (SFOMP), is proposed in this letter. The proposed SFOMP method is designed for compressive sensing and sparse signal recovery in the noisy environment. To improve the recovery performance, the SFOMP method incorporates a searching forward strategy to find the column leading to a minimum norm of residual error among the added candidates in each iteration. Numerical results show that, compared with other commonly used methods, this method provides a higher recovery signal‐to‐noise ratio, more accurate reconstruction of support set, and a competitive computational complexity with noisy measurements. [ABSTRACT FROM AUTHOR]

The potential application of surface modified nano‐SiO2 (NS) particles with poly (dimethyl diallyl ammonium chloride) (PDDA) has been reported in other fields, but not in civil construction. This paper aims to assess the influence of surface modified NS with PDDA on the early‐age hydration of cement paste, where cement is replaced by 0.3%, 1% and 3% of NS particle. PDDA can be introduced onto the surface of NS via long‐distance charge pairs. Calorimetric measurements of cement pastes with 0.35 w/b (water/binder) ratio show that NS particles accelerate the cement hydration, while PDDA retards it. Moreover, the cement hydration is controlled by PDDA at lower dosage of NS/PDDA particle, which delays the exothermic peaks of cement hydration, while the cement hydration is controlled by NS particle aggregates at higher dosage of NS/PDDA particle. Based on the results above, the mechanism of the adsorption of NS/PDDA particle on cement particle surfaces is proposed. [ABSTRACT FROM AUTHOR]