Angiotensin II type 2 receptors facilitate reinnervation of phenol-lesioned vascular calcitonin gene-related peptide (CGRP)-containing nerves in rat mesenteric arteries

The present study was designed to investigate involvement of angiotensin (Ang) II type 2 receptors (AT2 receptors) in restoration of perivascular nerve innervation injured by topical phenol treatment. Male Wistar rats underwent in vivo topical application of 10% phenol around the superior mesenteric artery. After phenol treatment, animals were subjected to immunohistochemistry of the third branch of small arteries, Western blot analysis of AT2 receptor protein expression in dorsal root ganglia (DRG) and studies of mesenteric neurogenic vasoresponsiveness. Ang II (750 ng/kg/day), nerve growth factor (NGF; 20 μg/kg/day) and PD123,319 (AT2 receptor antagonist; 10 mg/kg/day) were intraperitoneally administered for 7 days using osmotic mini-pumps immediately after topical phenol treatment. Losartan (AT1 receptor antagonist) was administered in drinking water (0.025%). Phenol treatment markedly reduced densities of both calcitonin gene-related peptide (CGRP)-like immunoreactivity (LI)- and neuropeptide Y (NPY)-LI-containing fibers. NGF restored densities of both nerve fibers to the Sham control level. Coadministration of Ang II and losartan significantly increased the density of CGRP-LI-fibers but not NPY-LI-fibers compared with saline control. The increase of the density of CGRP-LI-fibers by coadministration of Ang II and losartan was suppressed by adding PD123,319. Coadministration of Ang II and losartan ameliorated reduction of CGRP nerve-mediated vasodilation of perfused mesenteric arteries caused by phenol treatment. The AT2 receptor protein expression detected in DRG was markedly increased by NGF. These results suggest that selective stimulation of AT2 receptors by Ang II facilitates reinnervation of mesenteric perivascular CGRP-containing nerves injured by topical phenol application in the rat.</p

High-Resolution Spectroscopy of Ursa Major Moving Group Stars

We use new and extant literature spectroscopy to address abundances and membership for UMa moving group stars. We first compare the UMa, Coma, and Hyades H-R diagrams via a homogeneous set of isochrones, and find that these three aggregates are essentially coeval. Our spectroscopy of cool UMa dwarfs reveals striking abundance anomalies--trends with Teff, ionization state, and excitation potential--like those recently seen in young cool M34, Pleaides, and Hyades dwarfs. In particular, the trend of rising 7774 Ang-based OI abundance with declining Teff is markedly subdued in UMa compared to the Pleiades, suggesting a dependence on age or metallicity. Despite disparate sources of Li data,our homogeneous analysis indicates that UMa members evince remarkably small scatter in the Li-Teff plane for Teff>5200 K. Significant star-to-star scatter suggested by previous studies is seen for cooler stars. Comparison with the consistently determined Hyades Li-Teff trend reveals differences qualitatively consistent with this cluster's larger [Fe/H] (and perhaps slightly larger age). However, quantitative comparison with standard stellar models indicates the differences are smaller than expected, suggesting the action of a fourth parameter beyond age, mass, and [Fe/H] controlling Li depletion.Comment: To appear in Publ. Astron. Soc. Pacif. (September 2005

Examining Simple Joint Macroeconomic and Term-Structure Models: A Practitioner's Perspective

The primary objective of this paper is to compare a variety of joint models of the term structure of interest rates and the macroeconomy. To this end, we consider six alternative approaches. Three of these models follow from the work of Diebold and Li (2003) with a generalization in Bolder (2006). The fourth model is a regression-based approach motivated entirely by empirical considerations. The fifth model follows from the seminal work of Ang and Piazzesi (2003), who suggest a joint macro-finance model in a discrete-time affine setting. The final model, which we term an observed-affine model, represents an adjustment to the Ang-Piazzesi model that essentially relaxes restrictions on the state-variable dynamics by making them observable. The observed-affine model is similar in spirit to work by Colin-Dufresne, Goldstein, and Jones (2005) and Cochrane and Piazzesi (2006). Using monthly Canadian data from 1973 to 2005, we compare each of these models in terms of their out-of-sample ability to forecast the transition density of zero-coupon rates. We also examine a simple approach aimed at permitting a subset of the parameters in the non-affine models to vary over time. We find, similar to Bolder (2006), that the Diebold and Li (2003) motivated approaches provide the most appealing modelling alternative across our different comparison criteria.Econometric and statistical methods; Financial Markets; Interest rates

Massive MIMO 1-Bit DAC Transmission: A Low-Complexity Symbol Scaling Approach

We study multi-user massive multiple-input single-output (MISO) systems and focus on downlink transmission, where the base station (BS) employs a large antenna array with low-cost 1-bit digital-to-analog converters (DACs). The direct combination of existing beamforming schemes with 1-bit DACs is shown to lead to an error floor at medium-to-high SNR regime, due to the coarse quantization of the DACs with limited precision. In this paper, based on the constructive interference we consider both a quantized linear beamforming scheme where we analytically obtain the optimal beamforming matrix, and a non-linear mapping scheme where we directly design the transmit signal vector. Due to the 1-bit quantization, the formulated optimization for the non-linear mapping scheme is shown to be non-convex. To solve this problem, the non-convex constraints of the 1-bit DACs are firstly relaxed, followed by an element-wise normalization to satisfy the 1-bit DAC transmission. We further propose a low-complexity symbol scaling scheme that consists of three stages, in which the quantized transmit signal on each antenna element is selected sequentially. Numerical results show that the proposed symbol scaling scheme achieves a comparable performance to the optimization-based non-linear mapping approach, while its corresponding complexity is negligible compared to that of the non-linear scheme.Comment: 15 page

PENGARUH KONSENTRASI Li YANG DI-DOPING KE DALAM KATALIS MgO TERHADAP REAKSI TRANSESTERIFIKASI MINYAK SAWIT

Proses transesterifikasi dengan menggunakan katalis heterogen telah banyak dikaji untuk menggantikan peranan katalis KOH dan NaOH. Pendopingan ion litium (Li) ke dalam oksida logam Mampu meningkatkan aktivitas katalis heterogen dalam reaksi transesterifikasi. Penelitian ini dilakukan untuk- memberikan informasi mengenai pengaruh konsentrasi ion Li+ yang didoping ke dalam magnesium oksida (MgO) terhadap reaksi transesterifikasi minyak-sawit dengan kadar asam lemak bebas (ALB) yang tinggi menjadi metil ester, pada temperatur 120°C, rasio methanol: minyak- = 12:1, jumlah katalis 2,5 % putaran 800 rpm selam 2,5 jam menggunakan reaktor bertekanan. Variabel penelitian adalah konsentrasi Li yang didoping ke dalam MgO, yaitu 2 % 4 % 6 % 8 % 10 % Adapun parameter uji yang dilakukan adalah kandungan metil ester yang diperoleh dari hasil reaksi transesterifikasi dengan analisa Gas Chromtographi. Hasil penelitian menunjukkan bahwa konsentrasi Li yang di-doping pada MgO Paling optimum adalah 4 % dengan hasil 84,9808 % metil ester

Eucommia ulmoides

Cortex Eucommiae (Du-zhong) is the dried bark of the Eucommia ulmoides Oliv. The natural products identified from Du-zhong include lignans, iridoids, flavonoids, polysaccharides, terpenes, and proteins, Liu et al. (2012). Lignans, the main bioactive components, were protective against hypertensive renal injury in spontaneous hypertensive rats in our previous study, Li et al. (2012). Moreover, Eucommia lignans also diminished aldose reductase (AR) overexpression in the kidney, Li et al. (2012). However, the pathological mechanism underlying the protective effects of Eucommia lignans remains unknown. Cellular proliferation was reported to contribute to important pathological changes in hypertensive renal injuries, and increased angiotensin II (Ang II) expression was reported to be essential for target-organ damage during hypertension. Ang II is the main effective peptide in the renin-angiotensin system and is considered to be a key mediator in the development of hypertensive nephropathy, Rüster and Wolf (2011). Our preliminary results showed that Eucommia lignans had inhibitory effects on Ang II-induced proliferation of rat mesangial cells. In the present study, we investigated the effects of Eucommia ulmoides on Ang II-induced proliferation and apoptosis of rat mesangial cells. Cell cycle-related genes P21 and P27, and cell apoptosis-related genes Bax and Bcl-2, were determined

Alternative comparison in underspecified degree operators

This paper proposes a new theory for the recurrent ambiguities between the meaning of comparison, additivity, and continuation (CAC) across languages. The theory has two pillars. One is a semantic reanalysis of CAC meanings. I will show that all three meanings can be cashed out via comparisons between alternatives, and that by doing so we can establish inherent logical connections between them. The second pillar is a de-compositional analysis of lexical items expressing CAC meanings (henceforth CAC operators), which makes use of their logical connections to derive the ambiguities as results of underspecification.

A simple and novel method to obtain an FSR free silicon ring resonator

A simple and novel method to make a silicon ring resonator without the limit of free spectral range (FSR) is presented. For many applications, a ring resonator is desired with an ultra-wide FSR, a high quality factor, a large extinction ratio and low-fabrication complexity. In this paper we propose a novel method to obtain such a ring resonator, which is a single all-silicon micro-ring with a FSR as large as 150 nm around 1550 nm. It's based on the well-known phenomenon of resonance splitting