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Hypertension affects nearly half of the US population but only 43% achieved blood pressure control with medication alone. Medical devices for hypertension include implantable lead electrodes that stimulate the carotid baroreceptors with promising results, albeit with significant adverse complications. To address these limitations, we have proposed the use of deep peroneal nerve stimulation (DPNS), which elicited a depressor response in anesthetized, breathing supported, spontaneously hypertensive rats (SHR). In this study, we further define the electrical stimulation parameters that optimize the DPNS depressor response, and demonstrated that increasing the pulse duration from 0.15 ms to 1ms, of 1.0 mA pulses at 2 Hz for 10 sec, significantly reduced the mean arterial pressure (MAP) by 8±4 mmHg (p

The vector coding technique has been used to quantify coordination of two joints, segments, and/or planes during cyclic activities, such as walking. Coordination patterns can be identified by categorizing the tangent lines of an angle-angle plot by their direction, termed "coupling angle binning" or "phase binning". In the literature the ranges of directions, or "bins", originally divided by Chang et al. and more recently by Needham et al. have different strengths. Chang's method identifies general patterns with large bins while Needham's method identifies a dominant joint or segment in the pattern. This study created a novel method that incorporates bin categories from both methods, and therefore recognizes both general patterns and a dominant contributor when appropriate. This new method, the SRC method, as well as the two existing methods, were used to quantify knee-ankle coordination in the sagittal plane for healthy individuals and an individual with clubfoot during gait. Similarities and differences in classification between methods were compared and further investigated by interpreting the uncoupled angular data. Each method was then used to evaluate sagittal-coronal coordination of the forefoot in an individual with clubfoot during gait. This was done to demonstrate across-plane coordination analysis, to confirm that the advantages of the combined method extend to coupling pairs with like ranges of motion, and to present a clinical application. It was found that the TSRH binning methods provides a more complete description of coordination by including coordination categories defined by both the Chang and Needham method.

An integrated fluid inclusion and stable isotope study was carried out on hydrothermal veins (Sb-bearing quartz veins, metal-bearing fluorite–barite–quartz veins) from the Schwarzwald district, Germany. A total number of 106 Variscan (quartz veins related to Variscan orogenic processes) and post-Variscan deposits were studied by microthermometry, Raman spectroscopy, and stable isotope analysis. The fluid inclusions in Variscan quartz veins are of the H2O–NaCl–(KCl) type, have low salinities (0–10 wt.% eqv. NaCl) and high Th values (150–350°C). Oxygen isotope data for quartz range from +2.8‰ to +12.2‰ and calculated δ18OH2O values of the fluid are between −12.5‰ and +4.4‰. The δD values of water extracted from fluid inclusions vary between −49‰ and +4‰. The geological framework, fluid inclusion and stable isotope characteristics of the Variscan veins suggest an origin from regional metamorphic devolatilization processes. By contrast, the fluid inclusions in post-Variscan fluorite, calcite, barite, quartz, and sphalerite belong to the H2O–NaCl–CaCl2 type, have high salinities (22–25 wt.% eqv. NaCl) and lower Th values of 90–200°C. A low-salinity fluid (0–15 wt.% eqv. NaCl) was observed in late-stage fluorite, calcite, and quartz, which was trapped at similar temperatures. The δ18O values of quartz range between +11.1‰ and +20.9‰, which translates into calculated δ18OH2O values between −11.0‰ and +4.4‰. This range is consistent with δ18OH2O values of fluid inclusion water extracted from fluorite (−11.6‰ to +1.1‰). The δD values of directly measured fluid inclusion water range between −29‰ and −1‰, −26‰ and −15‰, and −63‰ and +9‰ for fluorite, quartz, and calcite, respectively. Calculations using the fluid inclusion and isotope data point to formation of the fluorite–barite–quartz veins under near-hydrostatic conditions. The δ18OH2O and δD data, particularly the observed wide range in δD, indicate that the mineralization formed through large-scale mixing of a basement-derived saline NaCl–CaCl2 brine with meteoric water. Our comprehensive study provides evidence for two fundamentally different fluid systems in the crystalline basement. The Variscan fluid regime is dominated by fluids generated through metamorphic devolatilization and fluid expulsion driven by compressional nappe tectonics. The onset of post-Variscan extensional tectonics resulted in replacement of the orogenic fluid regime by fluids which have distinct compositional characteristics and are related to a change in the principal fluid sources and the general fluid flow patterns. This younger system shows remarkably persistent geochemical and isotopic features over a prolonged period of more than 100 Ma.

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Contributions to Mineralogy and Petrology, 156 (6), ISSN:0010-7999, ISSN:1432-0967

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