Utilization of passive sonic telemetry as indicators of movement and nesting of the Northern Diamondback Terrapin (Malaclemys terrapin terrapin)

Numerous anthropogenic factors pose serious threats to estuarine ecosystems and the organisms inhabiting them. Bulkheading (i.e., construction of shoreline walls), dredging, boating, shoreline development, over-harvesting, and pollution are some of the major human impacts to estuaries in North America. The diamondback terrapin (Malaclemys terrapin) is an ideal species for determining the effects of human impacts to estuarine wildlife, because their habitat use and behavior uniquely utilize both land and aquatic habitats that comprise estuaries. The objective of this study is to determine the home range and nest site selection of diamondback terrapins in relation to anthropogenic impacts in Barnegat Bay Estuary, New Jersey. We will use passive sonic telemetry technology and multiple Submersible Underwater Receivers (SURs) to remotely track free-ranging terrapins throughout the Bay. We will position SURs in arrays throughout areas of the Bay where we have marked terrapins over the last three years to monitor the movements of individual terrapins. Fifteen terrapins will be outfitted with sonic transmitters per site, which will send signals to the SUR when terrapins are within range. Frequency, date, and time of signal reception will be logged remotely by each SUR. From these data we will determine the individual terrapin whose signal was received, and movements of individuals throughout the monitored areas. Gravid (i.e., egg-bearing) females will be closely monitored to determine the nest site(s) used. Reproductive success of nests will be determined for each monitored female. Wherever possible we will determine the cause(s) of nest failure. Our study will be critical in determining the direct and indirect effects of anthropogenic impacts to terrapins in areas of known high terrapin densities. These findings will aid in management decisions regarding both aquatic (e.g., boat) and land (e.g., beach) uses in relation to ensuring the viability of wildlife resources within the Barnegat Bay Estuary

Fragmentation and disk formation in high-mass star formation: the IRAM large program CORE

Interstellar matter and star formatio

ILLUMINATING THE DARKEST GAMMA-RAY BURSTS WITH RADIO OBSERVATIONS

We present X-ray, optical, near-infrared (IR), and radio observations of gamma-ray bursts (GRBs) 110709B and 111215A, as well as optical and near-IR observations of their host galaxies. The combination of X-ray detections and deep optical/near-IR limits establish both bursts as "dark." Sub-arcsecond positions enabled by radio detections lead to robust host galaxy associations, with optical detections that indicate z ≾ 4 (110709B) and z ≈ 1.8-2.9 (111215A). We therefore conclude that both bursts are dark due to substantial rest-frame extinction. Using the radio and X-ray data for each burst we find that GRB 110709B requires A_V^(host) ≳ 5.3 mag and GRB 111215A requires A_V^(host) ≳ 8.5 mag (assuming z = 2). These are among the largest extinction values inferred for dark bursts to date. The two bursts also exhibit large neutral hydrogen column densities of N H, int ≳ 10^(22) cm^(–2) (z = 2) as inferred from their X-ray spectra, in agreement with the trend for dark GRBs. Moreover, the inferred values are in agreement with the Galactic A_V -N_H relation, unlike the bulk of the GRB population. Finally, we find that for both bursts the afterglow emission is best explained by a collimated outflow with a total beaming-corrected energy of E_γ + E_K ≈ (7-9) × 10^(51) erg (z = 2) expanding into a wind medium with a high density, Ṁ ≈ (6-20) x 10^(-5) M_☉ yr^(–1) (n ≈ 100-350 cm^(–3) at ≈ 10^(17) cm). While the energy release is typical of long GRBs, the inferred density may be indicative of larger mass-loss rates for GRB progenitors in dusty (and hence metal rich) environments. This study establishes the critical role of radio observations in demonstrating the origin and properties of dark GRBs. Observations with the JVLA and ALMA will provide a sample with sub-arcsecond positions and robust host associations that will help to shed light on obscured star formation and the role of metallicity in GRB progenitors

Towards a holographic dual of large-N_c QCD

We study N_f D6-brane probes in the supergravity background dual to N_c D4-branes compactified on a circle with supersymmetry-breaking boundary conditions. In the limit in which the resulting Kaluza--Klein modes decouple, the gauge theory reduces to non-supersymmetric, four-dimensional QCD with N_c colours and N_f << N_c flavours. As expected, this decoupling is not fully realised within the supergravity/Born--Infeld approximation. For N_f = 1 and massless quarks, m_q = 0, we exhibit spontaneous chiral symmetry breaking by a quark condensate, \neq 0, and find the associated massless `pion' in the spectrum. The latter becomes massive for m_q > 0, obeying the Gell-Mann--Oakes--Renner relation: M_pi^2= - m_q / \f_pi^2. In the case N_f > 1 we provide a holographic version of the Vafa--Witten theorem, which states that the U(N_f) flavour symmetry cannot be spontaneously broken. Further we find N_f^2 - 1 unexpectedly light pseudo-scalar mesons in the spectrum. We argue that these are not (pseudo) Goldstone bosons and speculate on the string mechanism responsible for their lightness. We then study the theory at finite temperature and exhibit a phase transition associated with a discontinuity in the chiral condensate. D6/anti-D6 pairs are also briefly discussed.Comment: 43 pages, LaTeX; v3: Scalar vs. pseudo-scalar nature of mesons clarified, references added. v4: Small change in Acknowledgment

Meson Spectroscopy in AdS/CFT with Flavour

We compute the meson spectrum of an N=2 super Yang-Mills theory with fundamental matter from its dual string theory on AdS_5 x S_5 with a D7-brane probe. For scalar and vector mesons with arbitrary R-charge the spectrum is computed in closed form by solving the equations for D7-brane fluctuations; for matter with non-zero mass m_q it is discrete, exhibits a mass gap of order m_q / sqrt(g_s N) and furnishes representations of SO(5) even though the manifest global symmetry of the theory is only SO(4). The spectrum of mesons with large spin J is obtained from semiclassical, rotating open strings attached to the D7-brane. It displays Regge-like behaviour for J << sqrt(g_s N), whereas for J >> sqrt(g_s N) it corresponds to that of two non-relativistic quarks bound by a Coulomb potential. Meson interactions, baryons and `giant gauge bosons' are briefly discussed.Comment: LaTeX, 39 pages, 4 figures, uses epsf. v2: typos corrected. references adde

The Young Planetary System K2-25: Constraints on Companions and Starspots

The abundance of planets with orbital periods of a few to tens of days suggests that exoplanets experience complex dynamical histories. Planets in young stellar clusters or associations have well-constrained ages and therefore provide an opportunity to explore the dynamical evolution of exoplanets. K2-25b is a Neptune-sized planet in an eccentric, 3.48 day orbit around an M4.5 dwarf star in the Hyades cluster (650 Myr). In order to investigate its non-zero eccentricity and tight orbit, we analyze transit timing variations (TTVs) which could reveal clues to the migration processes that may have acted on the planet. We obtain 12 nonconsecutive transits using the MEarth observatories and long-term photometric monitoring, which we combine with 10 transits from the Spitzer Space Telescope and 20 transits from K2. Tables of MEarth photometry accompany this work. We fit each transit lightcurve independently. We first investigate whether inhomogeneities on the stellar surface (such as spots or plages) are differentially affecting our transit observations. The measured transit depth does not vary significantly between transits, though we see some deviations from the fiducial transit model. We then looked for TTVs as evidence of a nontransiting perturber in the system. We find no evidence for >1 M ? mass companions within a 2:1 period ratio, or for >5 M ? mass planets within a 7:2 period ratio

Short-term cost-effectiveness of one-stage implant-based breast reconstruction with an acellular dermal matrix versus two-stage expander-implant reconstruction from a multicentre randomized clinical trial

Background: Implant-based breast reconstruction (IBBR) is the most commonly performed reconstructive procedure and its economic impact is significant. This study aimed to analyse whether a direct one-stage IBBR with use of an acellular dermal matrix (ADM) is more cost-effective than two-stage (expander-implant) breast reconstruction. Methods: The BRIOS (Breast Reconstruction In One Stage) study was an open-label multicentre RCT in which women scheduled for skin-sparing mastectomy and immediate IBBR were randomized between one-stage IBBR with ADM or two-stage IBBR. Duration of surgery and hospital stay, and visits for the primary surgery, unplanned and cosmetic procedures were recorded. Costs were estimated at an institutional level. Health status was assessed by means of the EuroQol Five Dimensions 5L questionnaire. Results: Fifty-nine patients (91 breasts) underwent one-stage IBBR with ADM and 62 patients (92 breasts) two-stage IBBR. The mean(s.d.) duration of surgery in the one-stage group was significantly longer than that for two-stage IBBR for unilateral (2⋅52(0⋅55) versus 2⋅02(0⋅35) h; P < 0⋅001) and bilateral (4⋅03(1⋅00) versus 3⋅25(0⋅58) h; P = 0⋅017) reconstructions. Costs were higher for one-stage compared with two-stage IBBR for both unilateral (€12 448 (95 per cent c.i. 10 722 to 14 387) versus €9871 (9373 to 10 445) respectively; P = 0⋅025) and bilateral (€16 939 (14 887 to 19 360) versus €13 383 (12 414 to 14 669); P = 0⋅002) reconstructions. This was partly related to the use of relatively expensive ADM. There was no difference in postoperative health status between the groups. Conclusion: One-stage IBBR with ADM was associated with higher costs, but similar health status, compared with conventional two-stage IBBR. Registration number: NTR5446 (http://www .trialregister.nl)

Predictors of complications after direct-to-implant breast reconstruction with an acellular dermal matrix from a multicentre randomized clinical trial

Background: In the multicentre randomized trial BRIOS (Breast Reconstruction In One Stage), direct-to-implant (DTI) breast reconstruction with an acellular dermal matrix (ADM) was associated with a markedly higher postoperative complication rate compared with two-stage tissue expander/implant breast reconstruction. This study aimed to identify factors that contribute to the occurrence of complications after DTI ADM-assisted breast reconstruction. Methods: Data were obtained from the BRIOS study, including all patients treated with DTI ADM-assisted breast reconstruction. Logistic regression analyses were performed to identify factors predictive of postoperative complications. Results: Fifty-nine patients (91 breasts) were included, of whom 27 (35 breasts) developed a surgical complication. Reoperations were performed in 29 breasts (32 per cent), with prosthesis removal in 22 (24 per cent). In multivariable analyses, mastectomy weight was associated with complications (odds ratio (OR) 1·94, 95 per cent c.i. 1·33 to 2·83), reoperations (OR 1·70, 1·12 to 2·59) and removal of the implant (OR 1·55, 1·11 to 2·17). Younger patients (OR 1·07, 1·01 to 1·13) and those who received adjuvant chemotherapy (OR 4·83, 1·15 to 20·24) more frequently required reoperation. In univariable analyses, adjuvant radiotherapy showed a trend towards more complications (OR 7·23, 0·75 to 69·95) and removal of the implant (OR 5·12, 0·76 to 34·44), without reaching statistical significance. Conclusion: Breast size appeared to be the most significant predictor of complications in DTI ADM-assisted breast reconstruction. The technique should preferably be performed in patients with small to moderate sized breasts. Registration number: NTR5446 (http://www.trialregister.nl)

Robo-AO M-dwarf Multiplicity Survey: Catalog

We analyze observations from Robo-AO's field M dwarf survey taken on the 2.1 m Kitt Peak telescope and perform a multiplicity comparison with Gaia DR2. Through its laser-guided, automated system, the Robo-AO instrument has yielded the largest adaptive optics M dwarf multiplicity survey to date. After developing an interface to visually identify and locate stellar companions, we selected 11 low-significance Robo-AO detections for follow-up on the Keck II telescope using NIRC2. In the Robo-AO survey we find 553 candidate companions within 4″ around 534 stars out of 5566 unique targets, most of which are new discoveries. Using a position cross-match with DR2 on all targets, we assess the binary recoverability of Gaia DR2 and compare the properties of multiples resolved by both Robo-AO and Gaia. The catalog of nearby M dwarf systems and their basic properties presented here can assist other surveys which observe these stars, such as the NASA TESS mission