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Cenozoic extension in the Western Mediterranean has been related to the dynamics of back‐arc domains. Although, in most of its orogenic belts extension propagated into the fore‐arc nappe domains. Here we revisit the structure, metamorphism and radiometric ages of the Tunisian Tell, where HP/LT rocks (350°C at 0.8 GPa), were exhumed by the sequential activity of extensional detachments after heating and decompression (410°C–440°C at 0.6–0.3 GPa) in a plate convergent setting. Normal faults thinning the Tunisian Tell detached at two different crustal levels. The shallower one cuts down into the Atlas Mesozoic sequence, involving Tellian Triassic evaporites in the hanging‐wall forming halokinetic structures in the Mejerda basin late Miocene. The deeper‐detachment bounds metamorphic domes formed by marbles and metapsammites from the Atlas domain. Illite crystallinity on Triassic rocks shows epizonal to anchizonal values, at deep and intermediate structural depths of the Tell‐Atlas nappe belt, respectively. New U‐Pb 49.78 ± 1.28 Ma rutile ages from Tellian metabasites, together with existing phlogopite 23–17 Ma K‐Ar ages in Atlas marbles from the footwall of the deepest detachment, indicate a polymetamorphic evolution. The Tell rocks underthrusted the Kabylian flysch in the early Eocene. Further, early Miocene shortening thrusted the metabasites over lower‐grade sediments, producing HP/LT metamorphism and ductile stretching at the base of the Atlas belt. The exhumation of midcrustal roots of Western Mediterranean nappe belts after tectonic shortening is a common feature related to tearing at the edges of the subduction systems and inboard delamination of their subcontinental lithospheric mantle. Plain Language Summary: Mountain belts are formed by shortened sedimentary rocks. The Tell cordillera in Northern Tunisia is interpreted as a classic mountain belt developed through protracted shortening from the late Cretaceous until Present, formed by folded and overthrusted rocks, and intruded by salt bodies. However, we show here that conversely, some of the supposed salt bodies are formed by metamorphic rocks that were originally buried at depths of approximately 26 km. Moreover, the remaining salt structures in the Tunisian Tell formed in relation to the late‐stage thinning and collapse of the mountain belt, as they intrude through extensional faults into late Miocene sediments. We characterize the temperature and pressure conditions reached by the metamorphic rocks and obtain a 49 Ma age of an early metamorphic event by radiometric dating of rutile. Metamorphic rocks where also exhumed in other Western Mediterranean mountain belts like the Betics, Rif, Algerian Tell after the main shortening stage. We relate this process to delamination, a deep mantle tectonic mechanism, which strips the nappe belt crustal domain from its underlying mantle root. Key Points: The Tunisian Tell hosts High‐Pressure Low‐Temperature (HP/LT) domes underlying late Miocene extensional detachments, driven by slab delaminationMetamorphic and rutile U‐Pb data shows that rocks in Northern Tunisia reached HP/LT conditions in the early Eocene and early MioceneHalokinetic structures in Northern Tunisia are rooted in the Mejerda detachment and related to late Miocene extension [ABSTRACT FROM AUTHOR]

Abstract: Two orthogonal extensional systems produced the extensional collapse of the Tell and Atlas thrust belts in northern Tunisia during the Late Miocene to Pliocene in a context of NW‐SE plate convergence between Africa and Eurasia. The older extensional system shows several low‐angle normal faults (LANFs) and associated high‐angle faults with ENE‐directed transport that produced half‐grabens and hanging‐wall syncline basins during the late Tortonian to Messinian. The direction of extension swinged towards the SE during the Messinian, cutting into, and tilting the previous detachments. Extension was accompanied by the extrusion of 8‐Ma rhyodacites and Messinian basalts, together with the development of mineralized fault breccias. Plio‐Quaternary NW‐SE directed shortening formed inversion arrowhead structures, reverse faults, refolded extensional rollover anticlines and folded the LANFs. ENE‐directed extension is concomitant with the opening of the Tyrrhenian basin. We consequently think that both processes are related and that tearing of the Calabrian slab along the northern Tunisia coast drove the ENE‐directed extension. Meanwhile, the SE‐directed extension that followed was probably related to SE‐directed peeling back of the Tunisian continental lithospheric mantle during NW subduction of the Maghrebian margin. This extension propagated eastwards from the late Tortonian until the Pliocene following the SE migrating subduction front and favored by lateral slab tearing along the Tunisian Atlas dextral Subduction Transfer Edge Propagator boundary. This new hypothesis for the tectonic evolution of northern Tunisia shows for the first time the importance of crustal extension in the denudation of the Tunisian Atlas and Tell foreland thrust belts and its relation to deep mantle tectonic mechanisms. [ABSTRACT FROM AUTHOR]

Large strike-slip faults in the eastern Betics are interpreted to have developed in a transcurrent setting in response to 4-6 mm/yr of Africa-Iberia NW-SE convergence. However, here we show that some of these faults are transfer faults accommodating heterogeneous late Miocene extension. The North Cabrera dextral fault and other E-W to NE-SW strike-slip faults in the Sorbas basin were transfer faults produced under SW-NE extension. These faults together with related normal faults form the main boundaries of two sedimentary depocenters active between the Serravallian and the Tortonian. The older North Cabrera depocenter extended between the Serravallian and the early Tortonian (approximately 13.8 to 9 Ma), while the younger Gacía depocenter formed in response to late Tortonian extension (approximately 9 to 7.5 Ma). The latter formed to the west of the North Cabrera depocenter by a listric fan of normal faults with SW directed transport that are linked by dextral and sinistral transfer fault segments. These faults root on a low-angle detachment cutting into the exhumed high-pressure Nevado-Filabride complex rocks at ~0.8 km depth. The present work reveals that (1) this extension was partially coeval with and kinematically linked to sinistral displacement along the Carboneras fault farther south in the Níjar basin; (2) this westward directed extension produced elongated core complexes and tilted blocks to the north of the Carboneras fault and magmatic accretion upon thinned continental crust to the south, probably in response to slab tearing or detachment and associated edge delamination of the Iberian continental lithospheric mantle beneath the Betics. [ABSTRACT FROM AUTHOR]

Under field conditions water is often inadequate for satisfactory seedling establishment. This research investigated the field emergence and plant density of two lines (AB-medium and CD-tall) of sand bluestem (Andropogon hallii Hack.) and three generations of selection (Syn-0, Syn-1, and Syn-2). Populations AB-medium Syn-1 and AB-medium Syn-2 were developed from AB-medium Syn-0 using two cycles of recurrent selection for increased seed germination at a low water potential. Similarly, CD-tall Syn-1 and CD-tall Syn-2 were developed from CD-tall Syn-0. Our objective was to verify if the increase in seed germination of selected populations would also lead to an increase in field emergence and plant density. Field testing involved planting the six lines in a randomized block design replicated four times at three locations over a 3-yr period. Field emergence and plant density were determined using a frequency grid method at 30, 60, and 90 d after planting (DAP). Percentage field emergence and plant density varied only with sand bluestem line (P < 0.01), generation of selection (P < 0.01), and number of DAP (P < 0.05). Field emergence averaged 52.5, 57.4, and 61.1% for generation Syn-0, Syn-1, and Syn-2, respectively. Plant density averaged 13.8, 15.2, and 16.1 plants m-2 for generation Syn-0, Syn-1, and Syn-2, respectively. Therefore, selection for increased seed germination in sand bluestem also resulted in greater field emergence and higher plant density. [ABSTRACT FROM AUTHOR]

The combination of metamorphic petrology tools and in situ laser 40Ar/39Ar dating on phengite (linking time of growth, compositions and P–T conditions) enables us to identify a detailed P–T–d–t path for the still debated tectonometamorphic evolution of the Nevado-Filabride complex and infer new geodynamic-scale constraints. Our data show an isothermal decompression (at 550 °C) from 20 kbar for the Bédar-Macael unit and 14 kbar for the Calar Alto unit down to c. 3–4 kbar for both units at 2.8 mm year−1. At 22–18 Ma, this first part of the exhumation is followed by a final exhumation at 0.6 mm year−1 along a high-temperature low-pressure (HTLP) gradient of c. 60 °C km−1. The age of the peak of pressure is not precisely known but it is shown that it is around 30 Ma and possibly older, which is at variance with recent models suggesting a younger age for high-pressure (HP) metamorphism. Most of the exhumation is related to late-orogenic extension from c. 30 to 22–18 Ma. Thus the formation of the main ductile extensional shear zone, the Filabres Shear Zone (FSZ), occurred at 22–18 Ma and is clearly associated with a top-to-the-west shear sense once the FSZ is well localized. The transition from ductile to brittle then occurred at c. 14 Ma. The final exhumation, accommodated by brittle deformation, occurred from c. 14 to 9 Ma and was accompanied, from 12 to 8 Ma, by the formation of nearby extensional basins. The duration of the extensional process is c. 20 Myr which argues in favour of a progressive slab retreat from c. 30 to 9 Ma. The change in the shape of the P–T path at 22–18 Ma together with strain localization along the main top-to-the-west shear zone suggests that this date corresponds to a change in the direction of slab retreat from southwards to westwards. [ABSTRACT FROM AUTHOR]

Richards FH, Rea G. Reproductive decision making before and after predictive testing for Huntington's disease: an Australian perspective.A retrospective study examined both pre- and post-result reproductive decision making for 281 people at risk for Huntington's disease aged 18–45 years who had undergone predictive testing in one centre in Australia between 1990 and 2002. Forty-eight per cent of subjects had one or more pre-result pregnancies, and of these, three had prenatal linkage testing. One high-risk (50%) pregnancy was terminated. Four couples chose an alternative reproductive option. Following testing, data were available for 231 subjects, and no significant difference was found between mutation carriers and non-carriers in the occurrence of post-result pregnancies. This contrasts with the finding of a recent European study, although the outcome of the present study may have been influenced by loss of follow-up data for 50 subjects. Five carriers (17%) had a total of six prenatal tests. Four showed a carrier result and these pregnancies were terminated. Two carriers utilized an alternative reproductive option (donor insemination and pre-implantation genetic diagnosis). The results of this study confirm previous findings of a low uptake of prenatal testing and alternative reproductive options by people at risk for Huntington's disease undergoing predictive testing. [ABSTRACT FROM AUTHOR]

Thermobarometry using mica-chlorite local equilibria and structural analysis of three tectonic units of the Alpujarride complex in the southeastern Betics indicate that rocks that underwent low-pressure/low-temperature metamorphism are found below higher-grade blueschist facies rocks. Moreover, the high-pressure/low-temperature (HP/LT) units underwent contrasting (P-T) and structural evolutions. The structurally highest unit was exhumed in a typical postorogenic high-temperature geothermal context in the andalusite stability field, while the intermediate unit was exhumed following a cooling and decompression P-T path within the kyanite stability field. The superposition of the three units occurred during the lower Miocene related with north directed brittle-ductile shear zones and associated north vergent overturned folds, after postorogenic exhumation of the top unit. The coexistence of thrusting with lower and middle Miocene brittle extensional systems active in shallower levels of the Alboran orogenic wedge implies that extension was synorogenic. These data strengthen the hypothesis that rocks thinned by postorogenic extension during the latest Oligocene and lower Miocene were entrained in the lower to middle Miocene Alboran orogenic wedge. [ABSTRACT FROM AUTHOR]

Deals with the use of recordings, tapes and transcriptions in teaching French language in high school. Use of recordings in both aural and oral training in foreign language; Information on the use of the aural-oral approach of the Arlington State College, North Texas in language teaching; Description of the videotape 'Living French.'

The early (Devonian) collisional stage in SW Iberia has been investigated through the analysis of deformation in the Cubito-Moura schists, the main lithology of an Allochthonous Complex putatively rooted in the suture between the Ossa-Morena and South Portuguese zones. The first deformation in these schists (D1) is recorded as a S1-L1 mylonitic fabric well preserved in early quartz veins. Subsequent D2 deformation caused the main folds and the main (S2) foliation. After restoration, the stretching lineation (L1) trends at a small angle with the Ossa-Morena/South Portuguese suture. This trend, together with the top-to-the-east kinematics determined from quartz microfabric is indicative of an oblique left-lateral collisional scenario in SW Iberia. Chlorite-white K-mica-quartz ± chloritoid multi-equilibrium calculations yield P-T conditions in the range 0.9-1.2 GPa and 300-400 °C, during the first collisional stage. P-T conditions during D2 were 0.3-0.8 GPa and 400-450 °C, thus indicating an important stage of exhumation of the Allochthonous Complex during these two collisional events, after subduction of the Ossa-Morena Zone margin under the South Portuguese Zone continental crust. In the general context of the Variscan orogen, dominated by dextral collision, the left-lateral convergence in SW Iberia can be explained in terms of the Avalonian salient represented by the South Portuguese Zone, which would impinge between Iberia and Morocco. [ABSTRACT FROM AUTHOR]

BRWD3 has been described as a cause of X-linked intellectual disability, but relatively little is known about the specific phenotype. We report the largest BRWD3 patient series to date, comprising 17 males with 12 distinct null variants and 2 partial gene deletions. All patients presented with intellectual disability, which was classified as moderate (65%) or mild (35%). Behavioral issues were present in 75% of patients, including aggressive behavior, attention deficit/hyperactivity and/or autistic spectrum disorders. Mean head circumference was +2.8 SD (2.8 standard deviations above the mean), and mean BMI was +2.0 SD (in the context of a mean height of +1.3 SD), indicating a predominant macrocephaly/obesity phenotype. Shared facial features included a tall chin, prognathism, broad forehead, and prominent supraorbital ridge. Additional features, reported in a minority (<30%) of patients included cryptorchidism, neonatal hypotonia, and small joint hypermobility. This study delineates the clinical features associated with BRWD3 null variants and partial gene deletions, and suggests that BRWD3 should be included in the differential diagnosis of patients with an overgrowth-intellectual disability (OGID) phenotype, particularly in male patients with a mild or moderate intellectual disability associated with macrocephaly and/or obesity., (© 2019 Wiley Periodicals, Inc.)