4,365 research outputs found
Sensory processing in autism across exteroceptive and interoceptive domains
Objective: The current article discusses recent literature on perceptual processing in autism and aims to provide a critical review of existing theories of autistic perception and suggestions for future work. Method: We review findings detailing exteroceptive and interoceptive processing in autism and discuss their neurobiological basis as well as potential links and analogies between sensory domains. Results: Many atypicalities of autistic perception described in the literature can be explained either by weak neural synchronization or by atypical perceptual inference. Evidence for both mechanisms is found across the different sensory domains considered in this review. Conclusions: We argue that weak neural synchronization and atypical perceptual inference might be complementary neural mechanisms that describe the complex bottom-up and top-down differences of autistic perception, respectively. Future work should be sensitive to individual differences to determine if divergent patterns of sensory processing are observed within individuals, rather than looking for global changes at a group level. Determining whether divergent patterns of exteroceptive and interoceptive sensory processing may contribute to prototypical social and cognitive characteristics of autism may drive new directions in our conceptualization of autism
Origin of Nepheline-normative High-K Ankaramites and the Evolution of Eastern Srednogorie Arc in SE Europe
Eastern Srednogorie is part of the Apuseni-Banat-Timok-Srednogorie magmatic belt in SE Europe, the main arc related to the Late Cretaceous subduction and closure of the Tethys Ocean between Africa and Europe. Extrusive and shallow intrusive magmatism in the Eastern Srednogorie is abundant and extremely diverse in composition, covering a wide range from ultramafic volcanic rocks to granites; this provides a unique opportunity to study processes of primitive melt formation and magma evolution in an arc environment. In contrast to other parts of the belt, relatively mafic lavas predominate here. Three magmatic regions are distinguished within Eastern Srednogorie from south to north: Strandzha, Yambol-Burgas and East Balkan. Systematic differences exist between these regions, notably the increased alkalinity of samples from the Yambol-Burgas region in the central part. All rocks display a clear subduction-like signature in their trace-element patterns, particularly the enrichment in large ion lithophile elements and light rare earth elements relative to high field strength elements. A distinct primitive nepheline-normative ankaramite magma type is recognized among the mafic volcanic rocks from the Yambol-Burgas region and melt inclusions entrapped in olivine and clinopyroxene from a cumulitic rock. Lower crustal clinopyroxene and amphibole cumulates carried to the surface as xenoliths in a mafic dike represent a possible source for the ankaramite. Modeling of the melting process suggests that low degrees of batch melting of a clinopyroxene-rich, amphibole-bearing source similar to the cumulate xenoliths at 1 GPa, temperatures of 1240-1300°C, oxidized conditions and a water content of 0·2 wt % reproduce accurately most of the observed major- and trace-element characteristics of the studied ankaramites. The elevated Rb, K2O, Th, Ba content and higher Pb isotope ratios of the predicted liquids compared with the ankaramites are explained by mixing of the ankaramite magma with lherzolite partial melts derived from the subduction-modified mantle wedge. Underplating of such mantle-derived magmas at the crust-mantle boundary in an extensional environment as a response to slab roll-back provides also the necessary heat to melt lower crustal cumulates. Fractional crystallization of mainly clinopyroxene plus olivine and Fe-Ti oxides in a deep (equivalent to 8 kbar pressure) magma chamber produced most of the observed range of shoshonitic basalts and basaltic andesites in Eastern Srednogorie. The more evolved intermediate varieties were probably formed by mixing and crystallization at lower temperatures in lower pressure magma chambers. Whole-rock Sr and Pb isotope compositions indicate variable degrees of admixing of basement rocks to generate the intermediate to acid Late Cretaceous magmas, but assimilation was minimal for magmas with less than 53 wt % SiO2. The proposed model for the evolution of the magmatism in Eastern Srednogorie involves initial formation of the calc-alkaline and high-K arc magmatism in the Strandzha and East Balkan regions, followed by roll-back induced intra-arc rifting and the formation of high-K, shoshonitic and ultra-high-K magmatism, including primitive ankaramites in the Yambol-Burgas regio
Adakite-like and Normal Arc Magmas: Distinct Fractionation Paths in the East Serbian Segment of the Balkan-Carpathian Arc
New age and whole-rock 87Sr/86Sr and 143Nd/144Nd isotopic data are used to assess petrogenetic and regional geodynamic processes associated with Late Cretaceous subvolcanic intrusions within the sparsely studied Timok Magmatic Complex (TMC) and Ridanj-Krepoljin Zone (RKZ) of eastern Serbia. The TMC and RKZ form part of the Apuseni-Banat-Timok-Srednogorie (ABTS) magmatic belt, a Cu-Au mineralized calc-alkaline magmatic arc related to closure of the Tethys Ocean that extends through Romania, Serbia, and Bulgaria in SE Europe. Zircon ages based on U-Pb laser ablation inductively coupled plasma mass spectrometry supplemented by existing isotope dilution thermal ionization mass spectrometry data respectively range from 89 to 79 Ma and from 76 to 71 Ma for the TMC and RKZ. This age pattern corresponds to cross-arc younging away from the European continent. Adakite-like trace element signatures (Y â€18 ppm) are linked with samples that extend across the arc. These overlap in space and time with samples that conform to a normal arc differentiation trend. We performed energy-constrained assimilation-fractional crystallization (EC-AFC) modeling of Sr-La-Nd-Yb concentrations and Sr and Nd isotopic data. Results suggest that the two distinct fractionation trends may be explained in terms of a common mantle-derived parental magma but distinct fractionation and assimilation paths in the lower and upper crust. Petrogenesis of the adakite-like magmas is consistent with extensive high-pressure amphibole fractionation in the lower crust followed by ascent and plagioclase-dominant fractionation and assimilation in the upper crust. In contrast, normal arc signatures appear to have evolved exclusively via an upper-crustal differentiation process. Overall, our interpretation supports mantle wedge melting related to weak extension during progressive rollback of a subducting sla
Studies of the silencing of Baculovirus DNA binding protein
Baculovirus DNA binding protein (DBP) binds preferentially single-stranded DNA in vitro and colocalizes with viral DNA replication sites. Here, its putative role as viral replication factor has been addressed by RNA interference. Silencing of DBP in Autographa californica multiple nucleopolyhedrovirus-infected cells increased expression of LEF-3, LEF-4, and P35. In contrast, expression of the structural genes coding for P39 and polyhedrin was suppressed while expression of genes coding for P10 and GP64 was unaffected. In the absence of DBP, viral DNA replication sites were formed, indicating replication of viral DNA. Electron microscopy studies, however, revealed a loss of formation of polyhedra and virus envelopment, suggesting that the primary role of DBP is viral formation rather than viral DNA replication
HV/HR-CMOS sensors for the ATLAS upgradeâconcepts and test chip results
In order to extend its discovery potential, the Large Hadron Collider (LHC) will have a major upgrade (Phase II Upgrade) scheduled for 2022. The LHC after the upgrade, called High-Luminosity LHC (HL-LHC), will operate at a nominal leveled instantaneous luminosity of 5Ă 1034 cmâ2 sâ1, more than twice the expected Phase I . The new Inner Tracker needs to cope with this extremely high luminosity. Therefore it requires higher granularity, reduced material budget and increased radiation hardness of all components. A new pixel detector based on High Voltage CMOS (HVCMOS) technology targeting the upgraded ATLAS pixel detector is under study. The main advantages of the HVCMOS technology are its potential for low material budget, use of possible cheaper interconnection technologies, reduced pixel size and lower cost with respect to traditional hybrid pixel detector. Several first prototypes were produced and characterized within ATLAS upgrade R&D effort, to explore the performance and radiation hardness of this technology.
In this paper, an overview of the HVCMOS sensor concepts is given. Laboratory tests and irradiation tests of two technologies, HVCMOS AMS and HVCMOS GF, are also given
Radiation-hard active pixel sensors for HL-LHC detector upgrades based on HV-CMOS technology
Luminosity upgrades are discussed for the LHC (HL-LHC) which would make updates to the detectors necessary, requiring in particular new, even more radiation-hard and granular, sensors for the inner detector region.
A proposal for the next generation of inner detectors is based on HV-CMOS: a new family of silicon sensors based on commercial high-voltage CMOS technology, which enables the fabrication of part of the pixel electronics inside the silicon substrate itself.
The main advantages of this technology with respect to the standard silicon sensor technology are: low material budget, fast charge collection time, high radiation tolerance, low cost and operation at room temperature.
A traditional readout chip is still needed to receive and organize the data from the active sensor and to handle high-level functionality such as trigger management. HV-CMOS has been designed to be compatible with both pixel and strip readout.
In this paper an overview of HV2FEI4, a HV-CMOS prototype in 180 nm AMS technology, will be given. Preliminary results after neutron and X-ray irradiation are shown
Dynamical quantum noise in Bose-Einstein condensates
We introduce the study of dynamical quantum noise in Bose-Einstein
condensates through numerical simulation of stochastic partial differential
equations obtained using phase space representations. We derive evolution
equations for a single trapped condensate in both the positive- and Wigner
representations, and perform simulations to compare the predictions of the two
methods. The positive- approach is found to be highly susceptible to the
stability problems that have been observed in other strongly nonlinear, weakly
damped systems. Using the Wigner representation, we examine the evolution of
several quantities of interest using from a variety of choices of initial state
for the condensate, and compare results to those for single-mode models.Comment: 8 figures, submitted to Phys. Rev.
State determination in continuous measurement
The possibility of determining the state of a quantum system after a
continuous measurement of position is discussed in the framework of quantum
trajectory theory. Initial lack of knowledge of the system and external noises
are accounted for by considering the evolution of conditioned density matrices
under a stochastic master equation. It is shown that after a finite time the
state of the system is a pure state and can be inferred from the measurement
record alone. The relation to emerging possibilities for the continuous
experimental observation of single quanta, as for example in cavity quantum
electrodynamics, is discussed.Comment: 12 pages, 4 figures, Revte
Radiation Campaign of HPK Prototype LGAD sensors for the High-Granularity Timing Detector (HGTD)
We report on the results of a radiation campaign with neutrons and protons of
Low Gain Avalanche Detectors (LGAD) produced by Hamamatsu (HPK) as prototypes
for the High-Granularity Timing Detector (HGTD) in ATLAS. Sensors with an
active thickness of 50~m were irradiated in steps of roughly 2 up
to a fluence of . As a function of the
fluence, the collected charge and time resolution of the irradiated sensors
will be reported for operation at
Searches for Higgs bosons: preliminary combined results from the four LEP experiments at = 189 GeV
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