Amplitude and phase representation of quantum invariants for the time dependent harmonic oscillator

The correspondence between classical and quantum invariants is established. The Ermakov Lewis quantum invariant of the time dependent harmonic oscillator is translated from the coordinate and momentum operators into amplitude and phase operators. In doing so, Turski's phase operator as well as Susskind-Glogower operators are generalized to the time dependent harmonic oscillator case. A quantum derivation of the Manley-Rowe relations is shown as an example

MRAP deficiency impairs adrenal progenitor cell differentiation and gland zonation

Melanocortin 2 receptor accessory protein (MRAP) is a single transmembrane domain accessory protein and a critical component of the hypothamo-pituitary-adrenal axis. MRAP is highly expressed in the adrenal gland and is essential for adrenocorticotropin hormone (ACTH) receptor expression and function. Human loss-of-function mutations in MRAP cause familial glucocorticoid (GC) deficiency (FGD) type 2 (FGD2), whereby the adrenal gland fails to respond to ACTH and to produce cortisol. In this study, we generated Mrap-null mice to study the function of MRAP in vivo. We found that the vast majority of Mrap−/− mice died at birth but could be rescued by administration of corticosterone to pregnant dams. Surviving Mrap−/− mice developed isolated GC deficiency with normal mineralocorticoid and catecholamine production, recapitulating FGD2. The adrenal glands of adult Mrap−/− mice were small, with grossly impaired adrenal capsular morphology and cortex zonation. Progenitor cell differentiation was significantly impaired, with dysregulation of WNT4/β-catenin and sonic hedgehog pathways. These data demonstrate the roles of MRAP in both steroidogenesis and the regulation of adrenal cortex zonation. This is the first mouse model of isolated GC deficiency and reveals the role of MRAP in adrenal progenitor cell regulation and cortex zonatio

The Formal Dynamism of Categories: Stops vs. Fricatives, Primitivity vs. Simplicity

Minimalist Phonology (MP; Pöchtrager 2006) constructs its theory based on the phonological epistemological principle (Kaye 2001) and exposes the arbitrary nature of standard Government Phonology (sGP) and strict-CV (sCV), particularly with reference to their confusion of melody and structure. For Pöchtrager, these are crucially different, concluding that place of articulation is melodic (expressed with elements), while manner of articulation is structural. In this model, the heads (xN and xO) can license and incorporate the length of the other into their own interpretation, that is xN influences xO projections as well as its own and vice versa. This dynamism is an aspect of the whole framework and this paper in particular will show that stops and fricatives evidence a plasticity of category and that, although fricatives are simpler in structure, stops are the more primitive of the two. This will be achieved phonologically through simply unifying the environment of application of the licensing forces within Pöchtrager's otherwise sound onset structure. In doing so, we automatically make several predictions about language acquisition and typology and show how lenition in Qiang (Sino-Tibetan) can be more elegantly explained

Generalized Hamiltonian structures for Ermakov systems

We construct Poisson structures for Ermakov systems, using the Ermakov invariant as the Hamiltonian. Two classes of Poisson structures are obtained, one of them degenerate, in which case we derive the Casimir functions. In some situations, the existence of Casimir functions can give rise to superintegrable Ermakov systems. Finally, we characterize the cases where linearization of the equations of motion is possible

Two clinical markers for DLD in monolingual Italian speakers: what can they tell us about second language learners with DLD?

A large number of children worldwide are only exposed to their L2 around 3 years of age and can exhibit linguistic behaviours that resemble those of a child with Developmental Language Disorder (DLD). This can lead to under- or over-identification of DLD in this population. This study endeavors to contribute to overcoming this problem, by determining whether two specific clinical markers used with the Italian monolingual population can also be used with early L2 acquiring children, namely clitic production and non-word repetition. Our study involved two groups of 5-year-old L2 learners of Italian from various language backgrounds; 18 children had been referred to Speech and Language Therapy (SLT) services (EL2_DLD), and 30 children were typically developing (EL2_TD). The participants completed an Italian clitic production task and a non-word repetition task based on Italian phonotactics. Data was also collected from the participants' caregivers with the ALDeQ Parental Questionnaire to obtain information about the children's L1. Our results suggest that non-word repetition and clitic production in Italian are potentially useful for identifying L2 learners of Italian with DLD, at the age of 5 years. The repetition of non-words is highly accurate in identifying children with DLD among the participants, while clitic production is somewhat less discriminative in this sample. This study is a first step towards uncovering clinical markers that could be used to determine the presence of DLD in children acquiring their L2

Equivalence between free quantum particles and those in harmonic potentials and its application to instantaneous changes

This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedIn quantum physics the free particle and the harmonically trapped particle are arguably the most important systems a physicist needs to know about. It is little known that, mathematically, they are one and the same. This knowledge helps us to understand either from the viewpoint of the other. Here we show that all general time-dependent solutions of the free-particle Schrodinger equation can be mapped to solutions of the Schrodinger equation for harmonic potentials, both the trapping oscillator and the inverted `oscillator'. This map is fully invertible and therefore induces an isomorphism between both types of system, they are equivalent. A composition of the map and its inverse allows us to map from one harmonic oscillator to another with a different spring constant and different center position. The map is independent of the state of the system, consisting only of a coordinate transformation and multiplication by a form factor, and can be chosen such that the state is identical in both systems at one point in time. This transition point in time can be chosen freely, the wave function of the particle evolving in time in one system before the transition point can therefore be linked up smoothly with the wave function for the other system and its future evolution after the transition point. Such a cut-and-paste procedure allows us to describe the instantaneous changes of the environment a particle finds itself in. Transitions from free to trapped systems, between harmonic traps of different spring constants or center positions, or, from harmonic binding to repulsive harmonic potentials are straightforwardly modelled. This includes some time dependent harmonic potentials. The mappings introduced here are computationally more efficient than either state-projection or harmonic oscillator propagator techniques conventionally employed when describing instantaneous (non-adiabatic) changes of a quantum particle's environmentPeer reviewe

Anaphora Resolution in Near-Native Speakers of Italian

This study presents data from an experiment on the interpretation of intrasentential anaphora in Italian by native Italian speakers and by English speakers who have learned Italian as adults and have reached a near-native level of proficiency in this language. The two groups of speakers were presented with complex sentences consist-ing of a main clause and a subordinate clause, in which the subor-dinate clause had either an overt pronoun or a null subject pronoun. In half of the sentences the main clause preceded the subordinate clause (forward anaphora) and in the other half the subordinate clause preceded the main clause (backward anaphora). Participants performed in a picture verification task in which they had to indi-cate the picture(s) that corresponded to the meaning of the subor-dinate clause, thus identifying the possible antecedents of the null or overt subject pronouns. The patterns of responses of the two groups were very similar with respect to the null subject pronouns in both the forward and backward anaphora conditions. Compared to native monolingual speakers, however, the near-natives had a significantly higher preference for the subject of the matrix clause as a possible antecedent of overt subject pronouns, particularly in the backward anaphora condition. The results indicate that near-native speakers have acquired the syntactic constraints on pronom-inal subjects in Italian, but may have residual indeterminacy in the interface processing strategies they employ in interpreting pronom-inal forms

Developmental language disorder: Early predictors, age for the diagnosis, and diagnostic tools. A scoping review

Background. Developmental Language Disorder (DLD) is frequent in childhood and may have long-term sequelae. By employing an evidence-based approach, this scoping review aims at identifying (a) early predictors of DLD; (b) the optimal age range for the use of screening and diagnostic tools; (c) effective diagnostic tools in preschool children. Methods. We considered systematic reviews, meta-analyses, and primary observational studies with control groups on predictive, sensitivity and specificity values of screening and diagnostic tools and psycholinguistic measures for the assessment of DLD in preschool children. We identified 37 studies, consisting of 10 systematic reviews and 27 primary studies. Results. Delay in gesture production, receptive and/or expressive vocabulary, syntactic comprehension, or word combination up to 30 months emerged as early predictors of DLD, a family history of DLD appeared to be a major risk factor, and low socioeconomic status and environmental input were reported as risk factors with lower predictive power. Optimal time for screening is suggested between age 2 and 3, for diagnosis around age 4. Because of the high variability of sensitivity and specificity values, joint use of standardized and psycholinguistic measures is suggested to increase diagnostic accuracy. Conclusions. Monitoring risk situations and employing caregivers\u2019 reports, clinical assessment and multiple linguistic measures are fundamental for an early identification of DLD and timely interventions

Generation of kisspeptin-responsive GnRH neurons from human pluripotent stem cells

© 2017 Elsevier B.V. GnRH neurons are fundamental for reproduction in all vertebrates, integrating all reproductive inputs. The inaccessibility of human GnRH-neurons has been a major impediment to studying the central control of reproduction and its disorders. Here, we report the efficient generation of kisspeptin responsive GnRH-secreting neurons by directed differentiation of human Embryonic Stem Cells and induced-Pluripotent Stem Cells derived from a Kallman Syndrome patient and a healthy family member. The protocol involves the generation of intermediate Neural Progenitor Cells (NPCs) through long-term Bone morphogenetic protein 4 inhibition, followed by terminal specification of these NPCs in media containing Fibroblast Growth Factor 8 and a NOTCH inhibitor. The resulting GnRH-expressing and -secreting neurons display a neuroendocrine gene expression pattern and present spontaneous calcium transients that can be stimulated by kisspeptin. These in vitro generated GnRH expressing cells provide a new resource for studying the molecular mechanisms underlying the development and function of GnRH neurons

Expression of progenitor markers is associated with the functionality of a bioartificial adrenal cortex

This work was in part supported by the International Fund Congenital Adrenal Hyperplasia (IFCAH) (to SRB), by the Deutsche Forschungsgemeinschaft (CRC-TRR 127 (to SRB and BL), CRC-TRR 205 (to SRB, BL and CS), IRTG 2251 (to SRB, BL and CS), and CRU 252 (to SRB and BL)), the German Academic Exchange Service (DAAD) (to GRB) and The TransCampus initiative between TU Dresden and King’s College London (to SRB). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript