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The Late Jurassic–Early Cretaceous interval represents a prolonged marine deoxygenation period particularly in the Boreal–Arctic basins, the controlling factors of which remain poorly understood. Two drill cores totalling >450 m cover the Kimmeridgian–Barremian succession in contrasting locations in an evolving half-graben system (basin centre and near the footwall crest) in Wollaston Forland, NE Greenland; they provide an exceptional c. 20 myr long window into palaeoenvironmental development and changes in redox conditions within a detailed tectonostratigraphic framework. Synthesis of a multidisciplinary dataset including sedimentology, inorganic geochemistry and previously published organic geochemistry indicates that, despite continuous black mudstone accumulation from the Kimmeridgian to the Ryazanian, seafloor anoxia was intermittent in the Kimmeridgian, whereas more sustained anoxia or euxinia occurred in the middle Volgian–early Ryazanian. Correlation to reported contemporaneous successions along the Greenland margin indicates that protracted rifting and generation of localized seafloor topography were among the major drivers both of seafloor deoxygenation and current funnelling and amplification during the Jurassic–Cretaceous transition. Consequently, distribution of seaway current activity and dysoxia, anoxia and euxinia varied spatially, allowing fully oxygenated and anoxic pockets to coexist. Supplementary material: A facies table, summary of geochemistry data, geochemistry raw data and a sedimentological log from Store Koldewey are available at https://doi.org/10.6084/m9.figshare.c.6442539 [ABSTRACT FROM AUTHOR]

Due to its remarkable tolerance to high energy ionizing radiation, GaN has recently attracted attention as a promising material for dosimetry applications. However, materials issues that lead to persistent photoconductivity, poor sensitivity, and requirements for large operational voltages have been hurdles to realization of the full potential of this material. Here we demonstrate that the introduction of a two‐dimensional electron gas channel, through the addition of AlGaN/GaN heterointerfaces, can be used to create intrinsic amplification of the number of electrons that can be collected from single ionization events, yielding exceptionally large sensitivities in ultralow dose rate regimes. Furthermore, anomalous photo‐responses, which severely limit response times of GaN‐based devices, can be eliminated using these heterostructures. Measurements using focused monochromatic synchrotron radiation at 1–20 keV, as well as focused 20 MeV protons, reveal that these devices provide the capability for high sensitivity and resolution real time monitoring, which is competitive with and complementary to state‐of‐the‐art detectors. Therefore, AlGaN/GaN heterostructure devices are extremely promising for future applications in fields ranging from high energy physics to medical imaging.

The Barremian–Aptian upper Khami Group and Albian–Campanian Bangestan Group have been studied at outcrop in Lurestan, SW Iran. The upper Khami Group comprises a thin deltaic wedge (Gadvan Fm) transgressively overlain by shelfal carbonates (Dariyan Fm). The Dariyan Fm can be divided into lower and upper units separated by a major intra-Aptian fracture-controlled karst. The top of the Daryian Fm is capped by the Arabian plate-wide Aptian–Albian unconformity. The overlying Bangestan Group includes the Kazhdumi, Sarvak, Surgah and Ilam formations. The Kazhdumi Fm represents a mixed carbonate-clastic intrashelf basin succession, and passes laterally (towards the NE) into a low-angle Orbitolina-dominated muddy carbonate ramp/shoal (Mauddud Mbr). The Mauddud Mbr is capped by an angular unconformity and karst of latest Albian–earliest Cenomanian age. The overlying Sarvak Fm comprises both low-angle ramp and steeper dipping (5–10°) carbonate shelf/platform systems. Three regionally extensive karst surfaces are developed in the latest Cenomanian–Turonian interval of the Sarvak Fm, and are interpreted to be related to flexure of the Arabian plate margin due to the initiation of intra-oceanic deformation. The Surgah and Ilam Fm represent clastic and muddy carbonate ramp depositional systems respectively. Both The Khami and Bangestan groups have been affected by spectacularly exposed fracture-controlled dolomitization. Dolomite bodies are 100 m to several km in width, have plume-like geometry, with both fracture (fault/joint) and gradational diagenetic contacts with undolomitized country rock. Sheets of dolomite extend away from dolomite bodies along steeply dipping fault/joint zones, and as strata-bound bodies preferentially following specific depositional/diagenetic facies or stratal surfaces. There is a close link between primary depositional architecture/facies and secondary dolomitization. Vertical barriers to dolomitization are low permeability mudstones, below which dolomitizing fluids moved laterally. Where these barriers are cut by faults and fracture corridors, dolomitization can be observed to have advanced upwards, indicating that faults and joints were fluid migration conduits. Comparisons to Jurassic–Cenozoic dolomites elsewhere in Iran, Palaeozoic dolomites of North America and Neogene dolomites of the Gulf of Suez indicate striking textural, paragenetic and outcrop-scale similarities. These data imply a common fracture-controlled dolomitization process is applicable regardless of tectonic setting (compressional, transtensional and extensional).

An integrated structural and stratigraphic study of the Hammam Faraun fault block, Suez Rift, Egypt, provides insights into the tiff-initiation tectonostratigraphic evolution of the crustal-scale normal fault blocks. The shallow marine to offshore Tayiba Formation (Lower Oligocene) represents the youngest preserved pre-rift unit, and key stratal surface development indicates that relative sea-level variations exerted a marked control on its stratigraphic evolution. A major sea-level fall, which may have been a regional (i.e. eustatic) event, occurred during the mid-Oligocene and was synchronous with the onset of riffing. A major erosional unconformity (the base synrift unconformity) formed in response to the sea-level fall and defines a series of NNE-SSW- to NE-SW-trending palaeovalleys up to 40 m deep by 500 m wide, which are infilled by continental deposits and volcanic rocks of the Abu Zenima Formation (Upper Oligocene-Lower Miocene). During the rift initiation, palaeovalleys controlled depositional patterns and the evolving fault-controlled topography was insufficient to modify drainage patterns. Through time, however, surface-breaking faults began to exert a marked control on deposition. This study indicates the complexity that can occur during the rift-initiation phase caused by extrabasinal factors such as eustatic sea-level variations and antecedent drainage. [ABSTRACT FROM AUTHOR]

Aging populations and rising health costs have created the need to care for more patients in their own homes. Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO) is developing a project, Hospital Without Walls, which aims to provide continuous monitoring of patients in certain diagnostic categories. The key technology is a miniature, wearable, low-power radio that can transmit vital sign and activity information to a home computer, from which data may be sent by telephone line and the Internet to appropriate medical professionals. The initial clinical scenario for this work is monitoring of elderly patients who have presented to hospitals following repeated falls. Accelerometers built into the radio sets will monitor activity and detect and characterise falls. Simultaneous measurement of heart rate will provide information about abnormalities of cardiovascular physiology at the time of a fall. The system has been tested in laboratory conditions and is being adapted for initial clinical trials.

Summary To differentiate between B virus and HSV isolates from monkeys and man monoclonal antibodies (mabs) were produced to herpesvirus simiae (B virus) and herpes simplex type 1 and 2 (HSV-1 and HSV-2). Mabs were tested by indirect immunofluorescence (IFAT) for reactivity against herpesviruses from Asiatic monkeys (B virus), African monkeys (SA 8 virus), and man (HSV-1, HSV-2, varicella-zoster virus, cytomegalovirus, and Epstein-Barr virus). Mabs could be divided into groups A-E displaying specific reactivity for B virus (A); reactivity with both B virus and SA 8 but not HSV (B); reactivity with B virus, SA 8 virus and HSV strains (C); specific reactivity with HSV-1 (D); and specific reactivity with HSV-2 (E). Two of the B virus specific mabs were able to differentiate between cynomolgus and rhesus strains of B virus. None of the mabs reacted with human varicella-zoster virus, cytomegalovirus, or Epstein-Barr virus. A panel of mabs for the unequivocal identification of B virus isolates from monkey or man is proposed.

Reaction of 5-chloromethyl-3-phenyl-4,5-dihydroisoxazole with potassium t-butoxide in dimethyl sulphoxide gives 4-phenyl-2-oxa-3- azabicyclo[3,1,0]hex-3-ene in high yield and reaction of the 5-(1?- chloroethyl) homologue gives high yields of the diastereoisomeric 6- methyl derivatives of the bicyclic system. Some unsuccessful attempts to convert these bicyclic compounds into substituted cyclo-propanols and cyclopropenes are described.

Report of a meeting of the Tethyan Working Group, held at the University of Edinburgh, on 25-26 April 1991. The conveners were I. R. Sharp, T. Ustaomer, P. Degnan, A. H. F. Robertson and J. E. Dixon.

Gallium nitride has a remarkable tolerance to high energy ionizing radiation, but its full potential has not yet been realized due to material issues that lead to persistent photoconductivity, poor sensitivity, and requirements for large operational voltages. However, J. D. Howgate et al. (pp. 1562–1567) demonstrate that the introduction of a two‐dimensional electron gas channel, through the construction of AlGaN/GaN heterointerfaces, can be used to create “photomultiplier” equivalent amplification, while eliminating persistent photoconductivity, under operation with single volt bias at room temperature. These results are extremely promising for future ionizing radiation detector technologies for applications ranging from high energy physics to medical imaging. This is demonstrated on the front cover image, where a 3 × 3 mm flashlight bulb was scanned with ultra‐low dose rate (thousands of photons per second) focused X‐rays, clearly revealing the 50 μm thick spiral filament and the cavity in which it is mounted. Furthermore, such an image could be obtained within milliseconds via device miniaturization using conventional microelectronics techniques that allow for fabrication of integrated two‐dimensional pixel detectors. These extreme sensitivities could, for example, enable patient exposures to harmful ionizing radiation to be dramatically reduced or offer low power personal dosimeters capable of giving real‐time warning to radiation exposure.