Early Cretaceous biogeographic and oceanographic synthesis of Leg 123 (off Northwestern Australia)

Biogeographic observations made by Leg 123 shipboard paleontologists for Lower Cretaceous nannofossils, foraminifers, radiolarians, belemnites, and inoceramids are combined in this chapter to evaluate the paleoceanographic history of the northwestern Australian margin and adjacent basins. Each fossil group is characterized at specific intervals of Cretaceous time and compared with data from Tethyan and Southern Hemisphere high-latitude localities. Special attention is given to the biogeographic observations made for the Falkland Plateau (DSDP Legs 36 and 71) and the Weddell Sea (ODP Leg 113). Both areas have yielded valuable Lower Cretaceous fossil records of the circumantarctic high latitudes. In general, the Neocomian fossil record from DSDP and ODP sites off northwestern Australia has important southern high-latitude affinities and weak Tethyan influence. The same is true for the pelagic lithofacies: radiolarian chert and/or nannofossil limestone, dominant in the Tethyan Lower Cretaceous, are minor lithologies in the Exmouth-Argo sites. These observations, together with the young age of the Argo crust and plate tectonic considerations, suggest that the Argo Basin was not part of the Tethys Realm. The biogeography of the Neocomian radiolarian and nannofossil assemblages suggests opening of a seaway during the Berriasian that connected the circumantarctic area with the Argo Basin, which resulted in the influx of southern high-latitude waters. This conclusion constrains the initial fit and break-up history of Gondwana. Our results favor the loose fit of the western Australian margin with southeast India by Ricou et al. (1990), which accounts for a deeper water connection with the Weddell-Mozambique basins via drowned marginal plateaus as early as the Berriasian. In fits of the du Toit-type (1937), India would remain attached to Antarctica, at least until the late Valanginian, making such a connection impossible. After the Barremian, increasing Tethyan influence is evident in all fossil groups, although southern high-latitude taxa are still present. Biogeographic domains, such as the southern extension of Nannoconus and Ticinella suggest paleolatitudes of about 50°S for the Exmouth-Argo area. Alternatively, if paleolatitudes of about 35° are accepted, these biogeographic limits were displaced northward at least 15° along Australia in comparison to the southern Atlantic. In this case, the proto-circumantarctic current was deflected northward into an eastern boundary current off Australia and carried circumantarctic cold water into the middle latitudes. Late Aptian/early Albian time is characterized by mixing of Tethyan and southern faunal elements and a significant gradient in Albian surface-water temperatures over 10° latitude along the Australian margin, as indicated by planktonic foraminifers. Both phenomena may be indicative of convergence of temperate and antarctic waters near the Australian margin. High fertility conditions, reflected by radiolarian cherts, are suggestive of coastal upwelling during that time

A Search for Cosmic Microwave Background Anisotropies on Arcminute Scales with Bolocam

We have surveyed two science fields totaling one square degree with Bolocam at 2.1 mm to search for secondary CMB anisotropies caused by the Sunyaev- Zel'dovich effect (SZE). The fields are in the Lynx and Subaru/XMM SDS1 fields. Our survey is sensitive to angular scales with an effective angular multipole of l_eff = 5700 with FWHM_l = 2800 and has an angular resolution of 60 arcseconds FWHM. Our data provide no evidence for anisotropy. We are able to constrain the level of total astronomical anisotropy, modeled as a flat bandpower in C_l, with frequentist 68%, 90%, and 95% CL upper limits of 590, 760, and 830 uKCMB^2. We statistically subtract the known contribution from primary CMB anisotropy, including cosmic variance, to obtain constraints on the SZE anisotropy contribution. Now including flux calibration uncertainty, our frequentist 68%, 90% and 95% CL upper limits on a flat bandpower in C_l are 690, 960, and 1000 uKCMB^2. When we instead employ the analytic spectrum suggested by Komatsu and Seljak (2002), and account for the non-Gaussianity of the SZE anisotropy signal, we obtain upper limits on the average amplitude of their spectrum weighted by our transfer function of 790, 1060, and 1080 uKCMB^2. We obtain a 90% CL upper limit on sigma8, which normalizes the power spectrum of density fluctuations, of 1.57. These are the first constraints on anisotropy and sigma8 from survey data at these angular scales at frequencies near 150 GHz.Comment: 68 pages, 17 figures, 2 tables, accepted for publication in Ap

Use of Guided Wave Inspections to Monitor the Integrity of Nuclear Power Station Boilers

This paper describes a ground-breaking application of guided wave testing for the nuclear power industry. Hartlepool and Heysham 1 power stations in the UK contain boilers of a unique ‘pod’ design in which the spiral boiler tubes are supported from above by a central vertical ‘spine’, which is a tubular component approximately 520mm in diameter and 21m long with complex changes in cross-section and attachments along its length. There are 32 boilers in the two stations. The gas which has passed through the reactor core flows down over the boiler tubes, heating the water inside. Only the top 2m of each spine is accessible above the top of the boiler pod. Plant Integrity Ltd was engaged by to inspect these ‘spine’ supports in 2003 using its Teletest guided wave system at statutory outages, which occur on a 3-year interval for each reactor. The Teletest tool was positioned in the only accessible place, just below the inlet header which protrudes approximately 2m from the top of the boiler. A procedure was developed to enable the full 21m length of the spine inside the boiler pod itself to be examined. During one of the regular Teletest inspections, at Heysham 1 power station in September 2013, a significant change in response was detected from the central part of one of the boiler spines. As a result, two of the eight boilers at Heysham 1 Reactor 1 were shut down pending further investigations. The indication was confirmed to be a structurally significant crack in the spine concerned. The crack detected was at the exact position and of the approximate extent reported by Teletest, which had detected the flaw from some 10m away. All four reactors at Hartlepool and Heysham 1 power stations were shut down in the latter part of 2014 while a new safety case for return to service of the remaining boilers was made. There is currently no viable alternative to guided wave inspection for monitoring the integrity of these boiler spines and a significant programme of work has been carried out to demonstrate the performance of Teletest for detection of flaws in these components under a variety of circumstances in order to support the safety case for operation. This has involved theoretical modelling, review of information contained in historical inspection data, practical tests on a full scale mock-up component, development of high temperature Teletest tooling to allow in- service tests and production of automated Teletest data collection equipment to allow real time in-service monitoring of the spines. TWI’s and Plant Integrity’s support enabled all four reactors to be returned to service before the end of 2014

A Fluctuation Analysis of the Bolocam 1.1mm Lockman Hole Survey

We perform a fluctuation analysis of the 1.1mm Bolocam Lockman Hole Survey, which covers 324 square arcmin to a very uniform point source-filtered RMS noise level of 1.4 mJy/beam. The fluctuation analysis has the significant advantage of utilizing all of the available data. We constrain the number counts in the 1-10 mJy range, and derive significantly tighter constraints than in previous work: the power-law index is 2.7 (+0.18, -0.15), while the amplitude is equal to 1595 (+85,-238) sources per mJy per square degree, or N(>1 mJy) = 940 (+50,-140) sources/square degree (95% confidence). Our results agree extremely well with those derived from the extracted source number counts by Laurent et al (2005). Our derived normalization is about 2.5 times smaller than determined by MAMBO at 1.2mm by Greve et al (2004). However, the uncertainty in the normalization for both data sets is dominated by the systematic (i.e., absolute flux calibration) rather than statistical errors; within these uncertainties, our results are in agreement. We estimate that about 7% of the 1.1mm background has been resolved at 1 mJy.Comment: To appear in the Astrophysical Journal; 22 pages, 9 figure

Hydrogen sulfide protects renal grafts against prolonged cold ischemia-reperfusion injury via specific mitochondrial actions

This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1111/ajt.14080 This article is protected by copyright. All rights reserved.Accepted manuscript online: 15 October 2016Ischemia-reperfusion injury (IRI) is unavoidably caused by loss and subsequent restoration of blood flow during organ procurement and prolonged IRI results in increased rates of delayed graft function and early graft loss. The endogenously produced gasotransmitter, hydrogen sulfide (H2 S), is a novel molecule that mitigates hypoxic tissue injury. The current study investigates the protective mitochondrial effects of H2 S during in vivo cold storage and subsequent renal transplantation (RTx) and in vitro cold hypoxic renal injury. Donor allografts from Brown Norway rats treated with University of Wisconsin (UW) solution + H2 S (150 μM NaSH) during prolonged (24-hour) cold (4°C) storage exhibited significantly (p1000-fold compared to similar levels of the non-specific H2 S donor, GYY4137 and also improved syngraft function and survival following prolonged cold storage compared to UW. H2 S treatment mitigates cold IRI-associated renal injury via mitochondrial actions and could represent a novel therapeutic strategy to minimize the detrimental clinical outcomes of prolonged cold IRI during RTx.This work was supported by grants from Physicians Services Incorporated and the Canadian Urological Association (AS) and by a Frederick Banting and Charles Best Canada Graduate Scholarships Doctoral Award from the Canadian Institutes of Health Research (IL). MW and MEW would like to thank the Medical Research Council UK (MR/M022706/1) for their generous research support. RT would like to acknowledge the Brian Ridge Scholarship for support