The performance of bentonite barriers for high level radioactive waste (HLRW) disposal is currently being tested in various real-and up-scale disposal tests. One of the disposal tests, the ABM test (ABM = alternative buffer material), was conducted by SKB (Svensk Kärnbränslehantering) as a mediumscale experiment at the Äspö hard rock laboratory in Sweden. The present study deals with the second parcel (ABM-II), which was retrieved after 6.5 years with 2.5 years of water saturation and 3–4 years of heating up to 141°C. Nine different bentonites and two marine clays were tested to investigate the performance. The aim of the study was to provide a detailed characterization of the mineralogical and chemical changes that took place in ABM-II, compare the findings with ABM-I (the first of the six test parcels), and try to draw some general conclusions concerning the use of bentonites in such geotechnical barriers. The ABM-II test parcel revealed a set of reactions that a HLRW bentonite might undergo. The most prominent reaction was the rather complete exchange of cations, which was discussed in a second part to this publication (II — cation exchange; Dohrmann and Kaufhold, 2017). The corrosion of the Fe in metal canisters was observed, but no discrete corrosion product was identified. At the interface of bentonite and the metal canister, the formation of smectite-type trioctahedral clay minerals was observed. In contrast to the ABM-I test, anhydrite was present in many of the bentonite blocks of the ABM-II test. In most concepts used for HLRW disposal in crystalline rocks, a temperature below 100°C at the canister surface was applied to avoid boiling. In the ABM-II test, boiling of water was possibly observed. Throughout the experiment, a pressure/water loss was recorded in the upper part of the geotechnical barrier and water was added to maintain pressure in the bentonite. As a result of evaporation, NaCl crusts might have formed and the barrier was partly disintegrated. These results demonstrated that a reasonable assumption is that no boiling of water occurs in disposal concepts in which a pressure loss can occur.

Cathodoluminescence (CL) microscopy and spectroscopy combined with SHRIMP ion probe measurements were carried out on detrital zircons from the Cretaceous Weferlingen quartz sand (Germany) to distinguish and characterize different zircon populations.

Investigations by CL microscopy, SEM-CL and BSE imaging show that there are three main types of zircons (general grain sizes of 100–200 µm): (1) apparently weakly zoned, rounded grains with relict cores, (2) well rounded fragments of optically more or less homogeneous zircon grains showing CL zoning predominantly parallel to the z-axis, and (3) idiomorphic to slightly rounded zircon grains typically showing oscillatory euhedral CL zoning. A fourth type of low abundance is characterized by well-rounded grain fragments with an irregular internal structure showing bright yellow CL.

High-resolution CL spectroscopic analyses reveal that blue CL is mainly caused by an intrinsic emission band centered near 430 nm. Dy3+ is the dominant activator element in all zircons, whereas Sm3+, Tb3+, Nd3+ have minor importance. Yellow CL (emission band between 500 and 700 nm) is probably caused by electron defects localized on the [SiO4] groups (e.g. related to oxygen vacancies) or activation by Yb2+ generated by radiation. Variations of the integral SEM-CL intensity are mainly controlled by the intensity of the broad bands and the Dy3+ peaks.

SHRIMP analysis provides in situ high-resolution U-Pb dating of single zircon grains and confirms different ages for the evaluated different zircon types. The measurements show that the U-Pb ages of the zircons from Weferlingen scatter over a wide range (340 to 1750 Ma), backing up earlier conclusions that the quartz sand from Weferlingen is quite heterogeneous in terms of provenance.

Combined cathodoluminescence (CL) and transmitted light microscopy were used to characterize quartz from flat and steeply dipping quartz veins and from veinlets in banded host rocks from the giant Muruntau Au quartz vein deposit, Kyzyl Kum Desert, western Uzbekistan. The CL examinations were carried out using a ‘hot-cathode’ CL microscope linked to a highly sensitive digital video camera. The multi-stage deformed flat quartz veins and the steeply dipping hydrothermal formations at Muruntau are characterized by quartz with different CL colours, internal structures and degree of secondary alteration. Primary growth zoning of quartz, indiscernible in conventional polarized light was found to occur only in steeply dipping veins. The bulk of the high-grade Au mineralized ‘central’ quartz veins is dominated by one generation of hydrothermal quartz; intense brecciation of these veins is indicated by the occurrence of fragments of zoned quartz crystals. Primary growth zoning in quartz may be revealed not only by variations in the intensity of blue CL and/or by primary fluid inclusions arranged within the zones, but also by secondary inclusions and recrystallization phenomena developed along boundary surfaces between the zones. Using the results from CL imaging and microstructural analysis of the quartz, fluid inclusions investigated earlier were assigned to genetic types; the evidence of probably primary inclusions is of considerable importance for further studies of the geochemical conditions during vein formation. Considering geological and mineralogical data, CL studies of vein quartz may help to reveal the history of precipitation, deformation and recrystallization processes in the Muruntau Au ore field.

Samples of agate and quartz incrustations from different parent volcanic rocks of certain world-wide localities were investigated by EPR, CL and trace element analysis. In all agate samples the following paramagnetic centres were detected:, E′1, [AlO4]0 [FeO4/M+]0 and [GeO4/M+]0. Centres of the type [TiO4/Li+]0 and [TiO4/H+]0, which were detected in quartz of the parent volcanics, are absent in agate. Generally, the abundance of centres (silicon vacancy) and E′1 centres (oxygen vacancy) in agate is remarkably higher than in quartz. The high defect density in agates points to rapid growth of silica from a strongly supersaturated solution probably with a noncrystalline precursor.

CL microscopy reveals internal structures and zoning in agates and quartz incrustations which clearly differ from those discernible by conventional polarizing microscopy. The CL spectra of agates differ from those of quartz from crystalline rocks. At least three broad emission bands were detected in the CL spectra: a blue band of low intensity, a yellow band at about 580 nm, and an intense red band at 650 nm. The CL emission at 650 nm shows some relations to the hydroxyl or alkali content and the abundance of centres and E′1 centres. The emission intensity increases during electron bombardement due to the conversion of different precursors (e.g. ≡Si-O-H, ≡Si-O-Na groups) into hole centres. Another conspicuous feature in the CL spectra of agates is the existence of a yellow emission band centred at around 580 nm. The predominance of the yellow CL emission band and the high concentration of E′1 centres are typical for agates of acidic volcanics and are indicative of a close relationship between the two.

Cathodoluminescence (CL) imaging and spectroscopy, as well as backscattered electron imaging, were used to assign the occurrence of several mineral phases and rock structures in altered nordmarkites and calcite-bearing granites from the Nb-Zr-REE deposits from Khaldzan Buregte and Tsakhir (Mongolian Altai) to three events: (1) intrusion of barren nordmarkites; (2) intrusion of small bodies of calcite-bearing granites with metasomatic alteration of the wall-rocks; and (3) alteration by F-rich fluids.

Unusual red and yellow CL caused by Fe3+ and Mn2+ emission centres were detected in microcline and albite. Fe3+ centres were also established (along with others) in quartz, zircon, and possibly in fluorite.

Magmatic and metasomatic rock structures and internal structures of the minerals coexist in the samples. The primary magmatic features were in part preserved during alteration. In contrast, the internal and the centre structures may be changed during alteration even in non-replaced mineral phases. Euhedral minerals may be formed by secondary processes as shown for lath-shaped albite. The occurrence of pseudomorphs, the inheritance of elements during replacement, and the mechanical effects of secondary minerals on earlier mineral phases during metasomatic growth are proposed as criteria for the reconstruction of the mineral succession in altered rocks. Snowball structures may be formed as a result of metasomatic alteration rather than as a magmatic intergrowth.

LOFT (Large Observatory For X-ray Timing) is one of the four candidate missions currentlyunder assessment study for the M3 mission in ESAs Cosmic Vision program to be launched in2024. LOFT will carry two instruments with prime sensitivity in the 2–30 keV range: a 10m2 class large area detector (LAD) with a <1° collimated field of viewand a wide field monitor (WFM) instrument. The WFM is based on the coded mask principle,and 5 camera units will provide coverage of more than 1/3 of the sky. The prime goal ofthe WFM is to detect transient sources to be observed by the LAD. With its wide field ofview and good energy resolution of <500 eV, the WFM will be an excellent instrumentfor detecting and studying GRBs and X-ray flashes. The WFM will be able to detect~150 gamma ray bursts per year, and a burst alert system will enable thedistribution of ~100 GRB positions per year with a ~1 arcmin locationaccuracy within 30 s of the burst.

We report on the long term X-ray monitoring with Swift, RXTE, Suzaku, Chandra, and XMM-Newton of the outburst of the newly discovered magnetar Swift J1822.3–1606 (SGR 1822-1606), from the first observations soon after the detection of the short X-ray bursts which led to its discovery (July 2011), through the first stages of its outburst decay (April 2012). Our X-ray timing analysis finds the source rotating with a period of P = 8.43772016(2) s and a period derivative Ṗ = 8.3(2) × 10−14 ss−1, which entails an inferred dipolar surface magnetic field of B ≃ 2.7 × 1013 G at the equator. This measurement makes Swift J1822.3–1606 the second lowest magnetic field magnetar (after SGR 0418+5729; Rea et al. 2010). Following the flux and spectral evolution from the beginning of the outburst, we find that the flux decreased by about an order of magnitude, with a subtle softening of the spectrum, both typical of the outburst decay of magnetars. By modeling the secular thermal evolution of Swift J1822.3–1606, we find that the observed timing properties of the source, as well as its quiescent X-ray luminosity, can be reproduced if it was born with a poloidal and crustal toroidal fields of Bp ~ 1.5 × 1014 G and Btor ~ 7 × 1014 G, respectively, and if its current age is ~550 kyr (Rea et al. 2012).

National and international policies have encouraged the establishment of a representative network of marine protected areas (MPAs) in South Africa, with the aim of protecting marine biodiversity. The extent to which these marine and estuarine protected areas (EPAs) represent marine fish species and communities was assessed by comparing their species compositions with those of exploited areas, as sampled using four fishing techniques. Seven hundred fish species were sampled, representing one-third of South Africa's marine fishes. MPAs in coastal habitats scored c. 40% on the Bray-Curtis measure of similarity for species representativeness, but this score declined markedly for offshore ‘trawlable’ fishing grounds. The combined effects of sampling error, temporal variation and the effects of fishing on relative abundance suggest that 80% similarity would be the maximum achieveable. Forty-nine per cent of all fish species that were recorded were found in the 14 MPAs sampled. Redundancy in the MPA network was low, with fish species most commonly being represented in only one MPA or absent. There was greater redundancy in the 33 EPAs, with 40% of species being found in two or more EPAs, but many of these estuaries were adjacent to each other and embedded in large MPAs. Deep water fish communities (>80 m deep) and communities located on the west and south-east coasts of South Africa were most poorly represented by MPAs. Routine fishery surveys provide a robust and repeatable opportunity to assess species representativeness in MPAs, and the method used could form the basis of an operational definition of ‘representative’. In contrast to an assessment based on presence-absence data, this analysis of quantitative data presents a more pessimistic assessment of protection.

Ethnic disparities in chlamydia infections in The Netherlands were assessed, in order to compare two definitions of ethnicity: ethnicity based on country of birth and self-defined ethnicity. Chlamydia positivity in persons aged 16–29 years was investigated using data from the first round of the Chlamydia Screening Implementation (CSI, 2008–2009) and surveillance data from STI centres (2009). Logistic regression modelling showed that being an immigrant was associated with chlamydia positivity in both CSI [adjusted odds ratio (aOR) 2·3, 95% confidence interval (CI) 2·0–2·6] and STI centres (aOR 1·4, 95% CI 1·3–1·5). In both settings, 60% of immigrants defined themselves as Dutch. Despite the difference, classification by self-defined ethnicity resulted in similar associations between (non-Dutch) ethnicity and chlamydia positivity. However, ethnicity based on country of birth explained variation in chlamydia positivity better, and is objective and constant over time and therefore more useful for identifying young persons at higher risk for chlamydia infection.

Population size estimates of waders, gulls and terns passing through or breeding in Central Asia are very scarce, although highly important for global flyway population estimates as well as for targeting local conservation efforts. The Tengiz-Korgalzhyn region is one of the largest wetland complexes in Central Asia. We conducted surveys in this region between 1999 and 2008 and present estimates of population size as well as information on phenology and age structure for 50 species of Charadriiformes. The Tengiz-Korgalzhyn wetlands are especially important for Red-necked Phalaropes Phalaropus lobatus and Ruffs Philomachus pugnax with, respectively, 41% and 13% of their flyway populations using the area during spring migration. The region is also an important post-breeding moulting site for Pied Avocets Recurvirostra avosetta and Black-tailed Godwits Limosa limosa used by, respectively, 5% and 4% of their flyway populations. Besides its key importance as a migratory stopover site, the study area is a key breeding site for the Critically Endangered Sociable Lapwing Vanellus gregarius, the Near Threatened Black-winged Pratincole Glareola nordmanni and for Pallas’s Gull Larus ichthyaetus with 16%, 6% and 5% of their world populations, respectively. We identified 29 individual sites that held more than 1% of the relevant flyway populations of at least one species of Charadriiformes. Including data on other species of waterbirds (mainly waterfowl), there were 93 sites that qualify for Important Bird Areas (IBA). About half of them are protected in a state nature reserve, while an additional 20% are recognised as IBAs. Nevertheless, 28 important sites are currently not recognised as IBAs nor are they protected by other conservation means. These sites require conservation attention.

Two hundred and two house mice (Mus musculus L.) from 29 populations in Europe and North Africa were typed for 16 H-2K and 17 H-2D antigens, each antigen defining a different allele. Among the 13 best characterized populations, 1 to 4 common and 3 to 20 rare antigens were observed. However, an average of 37% of the H-2K and 39% of the H-2D antigens remain to be identified. Ninety-four percent of the 50 mice tested were heterozygous for H-2K antigens and 89% for H-2D antigens. In 4 of the 8 populations tested, the most common H-2K and H-2D antigens occurred in the same individual more often than if randomly associated. Associations between common H-2K and H-2D antigens and excess heterozygosities may be the consequence of the small size and instability of populations composed primarily of related individuals. Estimates of the genetic distances between populations revealed that Danish, Egyptian, and several of the Orkney Island populations were related. These were the only populations in which metacentric chromosomes were not found. In contrast, populations which were antigenically different were also karyotypically different, regardless of taxonomic status of allozymic similarity.

Background. A cardinal feature of schizophrenia is the sufferer's difficulty in interacting appropriately within the social milieu. This deficit has recently been associated with the concept of theory of mind, more commonly construed as a working model to understand behavioural patterns in autistic children. In this paper the complex relationships between theory of mind, IQ and psychoses are addressed.

Methods. Five experimental groups were used; non-psychiatric controls, affective disorder, schizophrenia with normal pre-morbid IQ, schizophrenia with pre-morbid IQ in the mildly learning disabled range, and mild learning disability with no history of psychiatric illness. All subjects were given a first order Theory of Mind Task and if successful, a second order Theory of Mind Task was then administered. All subjects were rated using the Positive and Negative Symptom Scale (PANSS).

Results. Subjects with schizophrenia and subjects with mild learning disability show impaired ability on a second order theory of mind task. However, when patients who are unable to answer reality questions are removed from the analysis specific impairment of theory of mind is only seen in subjects with schizophrenia. Furthermore, this impairment is relatively specific to particular psychopathological clusters in subjects with schizophrenia. Even though the same clusters of psychopathology are also seen in patients with affective disorder, their presence is not associated with poor second order theory of mind performance.

Conclusions. Impaired theory of mind on second order tests is specific to schizophrenia when compared to mild learning disability and affective disorder control groups. Subjects with schizophrenia and pre-morbid mild learning disability show greater impairment than subjects with schizophrenia and a pre-morbid IQ within the normal range.

Mg-doped GaN films grown by metalorganic chemical vapor deposition were characterized by variable-temperature Hall-effect measurements and Fourier-transform infrared absorption spectroscopy. As-grown, thermally activated, and deuterated Mg-doped GaN samples were investigated. The existence of Mg-H complexes in GaN is demonstrated with the observation of a local vibrational mode (LVM) at 3125 cm-1 (8 K). At 300 K this absorption line shifts to 3122 cm-1. The intensity of the LVM line is strongest in absorption spectra of as-grown GaN. Mg which is semi-insulating. Upon thermal activation, the intensity of the LVM line significantly decreases and an acceptor concentration of 2×1019cm-3 is derived from the Hall-effect data. After deuteration at 600°C the resistivity of the Mg-doped GaN increased by four orders of magnitude. A LVM line at 2321 cm-1 (8 K) appears in the absorption spectra which is consistent with the isotopie shift of the vibrational frequency when D is substituted for H.

We report on the OMVPE growth and characterization of AlGalnN and its heterostructures, including measurements of electrical properties (Hall), optical properties (photo- and cathodo- luminescence), structural characteristics (x-ray diffraction and TEM); and also the emission of InGaN/AlGaN heterostructures subject to optical and electrical pumping.

The activation of acceptors was investigated for Mg-doped, heteroepitaxial layers of GaN grown by metalorganic chemical vapor deposition. After growth the samples were exposed to isochronal rapid thermal anneals in the temperature range from 500°C to 775°C. The samples were studied by variable temperature Hall effect measurements and photoluminescence (PL) spectroscopy in the as-grown condition and after each temperature step. The thermal treatment leads to the formation of acceptors which are characterized by an activation energy for ionization in the range between 165 meV and 182 meV. These acceptors are attributed to Mg atoms substituting for Ga in the GaN lattice. The experimental results for the acceptor activation are consistent with the dissociation of electrically inactive acceptor-hydrogen complexes. The reversibility of this process is investigated by the exposure of the activated, p-type GaN samples to atomic hydrogen in a remote-plasma hydrogenation system at 600°C and reactivating at 850°C.

GaN thin films grown by molecular beam epitaxy (MBE) were characterized by Hall effect measurements in the temperature range from 80 K to 500 K and by photoluminescence spectroscopy (PL) at 2 K and at 300 K. These films were grown by MBE utilizing either electron cyclotron resonance (ECR) plasma activated nitrogen gas or thermally cracked hydrogen azide (HN3) as the source of chemically reactive nitrogen. The electrical properties of the GaN films grown by ECR plasma assisted MBE were found to vary with growth parameters, dominated either by shallow donors with activation energies (ΔE)in the range between 10 meV and 30 meV or deep donor levels (ΔE; > 500 meV). GaN grown by (HN3) gas-source MBE exhibited metallic conduction and electron mobilities <1 cm2/Vs. However, these films displayed sharp photoluminescence lines at 3.360 eV and 3.298 eV and no deep level related luminescence, whereas only broad deep level related emission was observed in the PL spectra of the ECR plasma assisted MBE grown GaN films.

Using the double pulse technique with two synchronized lasers, we studied the conditions of ignition and evolution of explosive crystallization. The structure of the resulting crystallized layers is analyzed by TEM. Results of calculations are reported describing the development of the two phase fronts: amorphous/molten and molten/crystalline. It is shown that the system takes more than 500 ns to reach the steady state. The experimental results support the model of creating first a melt nucleus in the amorphous layer followed by the formation of the crystalline nucleus in the molten sphere. Competitive solid phase nucleation and growth in the amorphous layer limit the temperature-time interval of melt nucleation. Defined explosively crystallized areas in laterally structured SOI layers are presented.