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We measure the central stellar velocity dispersion function for quiescent galaxies in a set of nine northern clusters in the redshift range 0.18 < z < 0.29 and with strong lensing arcs in Hubble Space Telescope images. The velocity dispersion function links galaxies directly to their dark matter halos. From dense SDSS and MMT/Hectospec spectroscopy, we identify 222–463 spectroscopic members in each cluster. We derive physical properties of cluster members including redshift, , and central stellar velocity dispersion and we include a table of these measurements for 3419 cluster members. We construct the velocity dispersion functions for quiescent galaxies with > 1.5 and within R200. The cluster velocity dispersion functions all show excesses at σ ≳ 250 km s−1 compared to the field velocity dispersion function. The velocity dispersion function slope at large velocity dispersion (σ > 160 km s−1) is steeper for more massive clusters, consistent with the trend observed for cluster luminosity functions. The spatial distribution of galaxies with large velocity dispersion at radii larger than R200 further underscores the probable major role of dry mergers in the growth of massive cluster galaxies during cluster assembly. [ABSTRACT FROM AUTHOR]

We describe a robust technique based on the ULySS IDL code for measuring velocity dispersions of galaxies observed with the MMT's fiber-fed spectrograph, Hectospec. This procedure is applicable to all Hectospec spectra having a signal-to-noise ratio ≳5 and weak emission lines. We estimate the internal error in the Hectospec velocity dispersion measurements by comparing duplicate measurements of 171 galaxies. For a sample of 984 galaxies with a median z = 0:10, we compare velocity dispersions measured by Hectospec through a 1.5" diameter optical fiber with those measured by the Sloan Digital Sky Survey (SDSS) and Baryon Oscillation Spectral Survey (BOSS) through 3" and 2" diameter optical fibers, respectively. The systematic differences between the Hectospec and the SDSS/BOSS measurements are <7% for velocity dispersions between 100 and 300 km s-1; the differences are no larger than the differences among the three BOSS velocity dispersion reductions. We analyze the scatter about the fundamental plane and find no significant redshift-dependent systematics in our velocity dispersion measurements to z ~ 0:6. This analysis also confirms our estimation of the measurement errors. In 1 hr in good conditions, we demonstrate that we achieve 30 km s-1 velocity dispersion errors for galaxies with an SDSS r fiber magnitude of 21. [ABSTRACT FROM AUTHOR]

Abstract Due to the long-term health risks now associated with hormone replacement therapy, many menopausal women are actively seeking alternative treatments. One such alternative is black cohosh (Actaea racemosa , syn. Cimicifuga racemosa ), which has been used in the United States for the treatment of gynecologic complaints for more than 100 years. Review of the published clinical data suggests that black cohosh may be useful for the treatment of menopausal symptoms, such as hot flashes, profuse sweating, insomnia, and anxiety. Results from the most recently published trial, however, indicate that black cohosh is not effective for the treatment of menopausal symptoms in breast cancer survivors being treated with tamoxifen. Because the overall quality of the published clinical trials is low, two new randomized, double-blind, placebo-controlled clinical trials are currently underway in the United States. To date, only one standardized black cohosh extract has been tested clinically; the current recommended dose is 40–80 mg per day. At least 4–12 weeks of treatment may be required before any therapeutic benefits may be apparent. Adverse reactions such as nausea, vomiting, headaches, dizziness, mastalgia, and weight gain have been observed in clinical trials. No drug interactions are reported in the medical literature. The estrogenic effects of black cohosh are controversial, and the more recent data indicate that black cohosh extracts may have an anti-estrogenic activity. Owing to potential effects on sex hormones, however, black cohosh should not be administered to children or during pregnancy and lactation. [ABSTRACT FROM AUTHOR]

This article presents a letter to the editor regarding an earlier article by E. Amster regarding the efficacy of herbal supplements.

Low-mass early-type galaxies, including dwarf spheroidals (dSph) and brighter dwarf ellipticals (dE), dominate the galaxy population in groups and clusters. Recently, an additional early-type population of more extended ultradiffuse galaxies (UDGs) has been identified, sparking a discussion on the potential morphological and evolutionary connections between the three classifications. Here, we present the first measurements of spatially resolved stellar kinematics from deep integrated-light spectra of KDG 64 (UGC 5442), a large dSph galaxy in the M 81 group. From these data, we infer stellar population properties and dark matter halo parameters using Jeans dynamical modelling. We find an old, metal-poor stellar population with no young stars and a dark matter mass fraction of ∼90 per cent within the half-light radius. These properties and the position of KDG 64 on the Fundamental Plane indicate that it is a local analogue of smaller UDGs in the Coma and Virgo clusters and is probably a transitional dSph-UDG object. Its evolutionary path cannot be uniquely established from the existing data, but we argue that supernovae feedback and tidal heating played key roles in shaping KDG 64. [ABSTRACT FROM AUTHOR]

HectoMAP is a dense redshift survey of 95,403 galaxies based primarily on MMT spectroscopy with a median redshift z = 0.345. The survey covers 54.64 deg2 in a 1.°5 wide strip across the northern sky centered at a decl. of 43.°25. We report the redshift, the spectral indicator D n 4000, and the stellar mass. The red-selected survey is 81% complete for 55,962 galaxies with (g − r) > 1 and r < 20.5; it is 72% complete for 32,908 galaxies with (g − r) > 1, (r − i) > 0.5 and 20.5 < r < 21.3. Comparison of the survey basis SDSS photometry with the HSC-SSP photometry demonstrates that HectoMAP provides complete magnitude-limited surveys based on either photometric system. We update the comparison between the HSC-SSP photometric redshifts with HectoMAP spectroscopic redshifts; the comparison demonstrates that the HSC-SSP photometric redshifts have improved between the second and third data releases. HectoMAP is a foundation for examining the quiescent galaxy population (63% of the survey), clusters of galaxies, and the cosmic web. HectoMAP is completely covered by the HSC-SSP survey, thus enabling a variety of strong- and weak-lensing investigations. [ABSTRACT FROM AUTHOR]

A validated and reproducible high-performance liquid chromatography (HPLC) method with in-line evaporative light scattering and photodiode array detection was developed for the analysis of major constituents in Black Cohosh (Cimicifuga racemosa L.). The method is based on the baseline chromatographic separation of 18 compounds reported to be present in Black Cohosh on a C-18 column (5 μm, 4.6 mm×250 mm) with water (0.05% trifluoroacetic acid, TFA)–acetonitrile–water as the mobile phase, and their in-line detection using photodiode array detector (PDA) and evaporative light scattering detector (ELSD). Sixteen of these (caffeic acid, ferulic acid, isoferulic acid, cimicifugoside H-1, cimiracemoside A, cimicifugoside H-2, (26R)-actein, 26-deoxycimicifugoside, (26S)-actein, 23-epi-26-deoxyactein, 23-OAc-shengmanol-3-O-β-d-xyloside, 26-deoxyactein, 25-OAc-cimigenol-3-O-α-l-arabinoside, 25-OAc-cimigenol-3-O-β-d-xyloside, cimigenol-3-O-α-l-arabinoside, cimigenol-3-O-β-d-xyloside) were detected to be present and quantifiable. The reputed two flavonoid constituents (kaempferol and formononetin) were not detectable.The validation of the method included tests for sensitivity, linearity, reproducibility, recovery and stability. The detection limits were found to be in the range of 26–55 ng (10 μl per injection) in ELSD for the 16 constituents of Black Cohosh. The exponential linear calibration curves were observed for all the constituents tested with r2 being >0.99. The reproducibility of the method was evaluated by analyzing three sets of controls on three consecutive days (n=3) with R.S.D. (%) and relative error (%) <8.14 and 11.27%, respectively. The observed recovery rates were better than 91.75%. The stability of Black Cohosh methanolic sample solution was assessed by consecutively analyzing the methanolic solutions prepared from liquid extract (Sample A), powered extract (Sample B), milled plant material (Sample C) and one of the commercial product (Sample D1) for the content of 16 major constituents with the relative standard deviations (R.S.D., %) <6.39%, indicating the sample matrix of Black Cohosh is stable.Contrary to literature reports, kaempferol and formononetin were not detected in either our field collected plant materials or commercial products of Black Cohosh in the current assay. [Copyright &y& Elsevier]

The dominant physical processes responsible for the formation and longevity of giant gaseous and stellar discs in galaxies remain controversial. Although they are rare (less than 10 confirmed as of now), giant low-surface brightness (gLSB) discy galaxies provide interesting insights given their extreme nature. We describe observations of UGC 1378 including deep spectroscopy with the Russian 6-m telescope and multiband imaging with Binospec at the MMT. Galaxy UGC 1378 has both high surface brightness and an extended low surface brightness discs. Our stellar velocity dispersion data for the high surface brightness, Milky Way sized, disc appears inconsistent with a recent major merger, a widely discussed formation scenario for the very extended low surface brightness disc. We estimate the star formation rates (SFRs) from archival Wide-Field Infrared Survey Explorer data. The SFR surface density in the LSB disc is low relative to its gas density, consistent with recent gas accretion. We argue that the unusually large size of UGC 1378's disc may be the product of a rich gas reservoir (e.g. a cosmic filament) and an isolated environment that has preserved the giant disc. [ABSTRACT FROM AUTHOR]

We describe the new spectroscopic data reduction pipeline for the multi-object MMT/Magellan Infrared Spectrograph. The pipeline is implemented in IDL as a stand-alone package and is publicly available in both stable and development versions. We describe novel algorithms for sky subtraction and correction for telluric absorption. We demonstrate that our sky subtraction technique reaches the Poisson limit set by the photon statistics. Our telluric correction uses a hybrid approach by first computing a correction function from an observed stellar spectrum, and then differentially correcting it using a grid of atmosphere transmission models for the target airmass value. The pipeline provides a sufficient level of performance for real time reduction and thus enables data quality control during observations. We reduce an example dataset to demonstrate the high data reduction quality. [ABSTRACT FROM AUTHOR]

Megacam is a large-format optical camera that can be operated at the f/5 Cassegrain foci of the MMT on Mount Hopkins, Arizona, and the Magellan Clay telescope at Las Campanas Observatory, Chile. Megacam's focal plane is composed of 36 closely packed e2v CCD42-90 CCDs, each with 2048 × 4608 pixels, assembled in an 18; 432 × 18; 432 array. Two additional CCD42-90s are provided for autoguiding and focus control. The CCDs have 13:5 µm square pixels that subtend 0:"08 at the f/5 foci, yielding a 250 × 250 field-of-view. The camera system includes a focal plane shutter, two filter wheels, two liquid nitrogen reservoirs, a central chamber that holds the CCD mosaic array, and two electronics boxes. Megacam is equipped with a variety of broadband and narrowband filters. Software features include automatic calculation of twilight flat exposure times. [ABSTRACT FROM AUTHOR]

Weak lensing provides an important route toward collecting samples of clusters of galaxies selected by mass. Subtle systematic errors in image reduction can compromise the power of this technique. We use the B-mode signal to quantify this systematic error and to test methods for reducing this error. We show that two procedures are efficient in suppressing systematic error in the B-mode: (1) refinement of the mosaic CCD warping procedure to conform to absolute celestial coordinates and (2) truncation of the smoothing procedure on a scale of 10′. Application of these procedures reduces the systematic error to 20% of its original amplitude. We provide an analytic expression for the distribution of the highest peaks in noise maps that can be used to estimate the fraction of false peaks in the weak-lensing κ-signal-to-noise ratio (S/N) maps as a function of the detection threshold. Based on this analysis, we select a threshold S/N = 4.56 for identifying an uncontaminated set of weak-lensing peaks in two test fields covering a total area of ∼3 deg2. Taken together these fields contain seven peaks above the threshold. Among these, six are probable systems of galaxies and one is a superposition. We confirm the reliability of these peaks with dense redshift surveys, X-ray, and imaging observations. The systematic error reduction procedures we apply are general and can be applied to future large-area weak-lensing surveys. Our high-peak analysis suggests that with an S/N threshold of 4.5, there should be only 2.7 spurious weak-lensing peaks even in an area of 1000 deg2, where we expect ∼2000 peaks based on our Subaru fields. [ABSTRACT FROM AUTHOR]

We compare galaxy clusters selected in Chandra and XMM-Newton X-ray observations of the 4 deg2 Deep Lens Survey (DLS) F2 field to the cluster samples previously selected in the same field from a sensitive weak-lensing shear map derived from the DLS and from a detailed galaxy redshift survey—the Smithsonian Hectospec Lensing Survey (SHELS). Our Chandra and XMM-Newton observations cover 1.6 deg2 of the DLS F2 field, including all 12 weak-lensing peaks above a signal-to-noise ratio of 3.5, along with 16 of the 20 SHELS clusters with published velocity dispersions >500 km s–1. We detect 26 extended X-ray sources in this area and confirm 23 of them as galaxy clusters using the optical imaging. Approximately 75% of clusters detected in either X-ray or spectroscopic surveys are found in both; these follow the previously established scaling relations between velocity dispersion, LX, and TX. A lower percentage, 60%, of clusters are in common between X-ray and DLS samples. With the exception of a high false-positive rate in the DLS weak-lensing search (5 out of 12 DLS candidates appear to be false), differences between the three cluster detection methods can be attributed primarily to observational uncertainties and intrinsic scatter between different observables and cluster mass. [ABSTRACT FROM AUTHOR]

We relate transitions in galaxy structure and gas content to refueling, here defined to include both the external gas accretion and the internal gas processing needed to renew reservoirs for star formation. We analyze two z = 0 data sets: a high-quality ∼200 galaxy sample (the Nearby Field Galaxy Survey, data release herein) and a volume-limited ∼3000 galaxy sample with reprocessed archival data. Both reach down to baryonic masses ∼109M☼ and span void-to-cluster environments. Two mass-dependent transitions are evident: (1) below the “gas-richness threshold” scale (V ∼ 125 km s–1), gas-dominated quasi-bulgeless Sd-Im galaxies become numerically dominant; while (2) above the “bimodality” scale (V ∼ 200 km s–1), gas-starved E/S0s become the norm. Notwithstanding these transitions, galaxy mass (or V as its proxy) is a poor predictor of gas-to-stellar mass ratio Mgas/M*. Instead, Mgas/M* correlates well with the ratio of a galaxy's stellar mass formed in the last Gyr to its preexisting stellar mass, such that the two ratios have numerically similar values. This striking correspondence between past-averaged star formation and current gas richness implies routine refueling of star-forming galaxies on Gyr timescales. We argue that this refueling underlies the tight Mgas/M* versus color correlations often used to measure “photometric gas fractions.” Furthermore, the threshold and bimodality scale transitions reflect mass-dependent demographic shifts between three refueling regimes—accretion-dominated, processing-dominated, and quenched. In this picture, gas-dominated dwarfs are explained not by inefficient star formation but by overwhelming gas accretion, which fuels stellar mass doubling in ≲1 Gyr. Moreover, moderately gas-rich bulged disks such as the Milky Way are transitional, becoming abundant only in the narrow range between the threshold and bimodality scales. [ABSTRACT FROM AUTHOR]

Abstract: Background: Since ephedra-containing dietary supplements were banned from the US market, manufacturers changed their formulations by eliminating ephedra and replacing with other botanicals, including Citrus aurantium, or bitter orange. Bitter orange contains, among other compounds, synephrine, a chemical that is chemically similar to ephedrine. Since ephedrine may have cardiovascular effects, the goal of this study was to investigate the cardiovascular effects of various doses of bitter orange extract and pure synephrine in rats. Method: Female Sprague–Dawley rats were dosed daily by gavage for 28days with synephrine from two different extracts. One extract contained 6% synephrine, and the other extract contained 95% synephrine. Doses were 10 or 50mg synephrine/kg body weight from each extract. Additionally, caffeine was added to these doses, since many dietary supplements also contain caffeine. Telemetry was utilized to monitor heart rate, blood pressure, body temperature and QT interval in all rats. Results and conclusion: Synephrine, either as the bitter orange extract or as pure synephrine, increased heart rate and blood pressure. Animals treated with 95% synephrine showed minimal effects on heart rate and blood pressure; more significant effects were observed with the bitter orange extract suggesting that other components in the botanical can alter these physiological parameters. The increases in heart rate and blood pressure were more pronounced when caffeine was added. None of the treatments affected uncorrected QT interval in the absence of caffeine. [Copyright &y& Elsevier]

The use of botanicals and dietary supplements derived from natural substances as an adjunct to an improved quality of life or for their purported medical benefits has become increasingly common in the United States. This review addresses the safety assessment and regulation of food products containing these substances by the U.S. Food and Drug Administration (FDA). The issue of safety is particularly critical given how little information is available on the toxicity of some of these products. The first section uses case studies for stevia and green tea extracts as examples of how FDA evaluates the safety of botanical and herbal products submitted for consideration as Generally Recognized as Safe under the Federal Food, Drug, and Cosmetics Act. The 1994 Dietary Supplement Health Education Act (DSHEA) created a regulatory framework for dietary supplements. The article also discusses the regulation of this class of dietary supplements under DSHEA and addresses the FDA experience in analyzing the safety of natural ingredients described in pre-market safety submissions. Lastly, we discuss an ongoing interagency collaboration to conduct safety testing of nominated dietary supplements. [ABSTRACT FROM AUTHOR]

We use a dense, complete redshift survey, the Smithsonian Hectospec Lensing Survey (SHELS), covering a 4 deg2 region of a deep imaging survey, the Deep Lens Survey (DLS), to study the optical spectral properties of Wide-field Infrared Survey Explorer (WISE) 22 μm selected galaxies. Among 507 WISE 22 μm selected sources with (S/N)22 μm ⩾ 3 (≈S22 μm ≳ 2.5 mJy), we identify the optical counterparts of 481 sources (∼98%) at R < 25.2 in the very deep, DLS R-band source catalog. Among them, 337 galaxies at R < 21 have SHELS spectroscopic data. Most of these objects are at z < 0.8. The infrared (IR) luminosities are in the range 4.5 × 108(L☼) ≲ LIR ≲ 5.4 × 1012(L☼). Most 22 μm selected galaxies are dusty star-forming galaxies with a small (<1.5) 4000 Å break. The stacked spectra of the 22 μm selected galaxies binned in IR luminosity show that the strength of the [O III] line relative to Hβ grows with increasing IR luminosity. The optical spectra of the 22 μm selected galaxies also show that there are some (∼2.8%) unusual galaxies with very strong [Ne III] λ3869, 3968 emission lines that require hard ionizing radiation such as active galactic nuclei (AGNs) or extremely young massive stars. The specific star formation rates (sSFRs) derived from the 3.6 and 22 μm flux densities are enhanced if the 22 μm selected galaxies have close late-type neighbors. The sSFR distribution of the 22 μm selected galaxies containing AGNs is similar to the distribution for star-forming galaxies without AGNs. We identify 48 dust-obscured galaxy candidates with large (≳ 1000) mid-IR to optical flux density ratio. The combination of deep photometric and spectroscopic data with WISE data suggests that WISE can probe the universe to z ∼ 2. [ABSTRACT FROM AUTHOR]