Digital second-order phase-locked loop

A digital second-order phase-locked loop is disclosed in which a counter driven by a stable clock pulse source is used to generate a reference waveform of the same frequency as an incoming waveform, and to sample the incoming waveform at zero-crossover points. The samples are converted to digital form and accumulated over M cycles, reversing the sign of every second sample. After every M cycles, the accumulated value of samples is hard limited to a value SGN = + or - 1 and multiplied by a value delta sub 1 equal to a number of n sub 1 of fractions of a cycle. An error signal is used to advance or retard the counter according to the sign of the sum by an amount equal to the sum

Black-holes, topological strings and large N phase transitions

The counting of microstates of BPS black-holes on local Calabi-Yau of the form ${\mathcal O}(p-2)\oplus{\mathcal O}(-p) \longrightarrow S^2$ is explored by computing the partition function of q-deformed Yang-Mills theory on $S^2$. We obtain, at finite $N$, the instanton expansion of the gauge theory. It can be written exactly as the partition function for U(N) Chern-Simons gauge theory on a Lens space, summed over all non-trivial vacua, plus a tower of non-perturbative instanton contributions. In the large $N$ limit we find a peculiar phase structure in the model. At weak string coupling the theory reduces to the trivial sector and the topological string partition function on the resolved conifold is reproduced in this regime. At a certain critical point, instantons are enhanced and the theory undergoes a phase transition into a strong coupling regime. The transition from the strong coupling phase to the weak coupling phase is of third order.Comment: 16 pages, 3 figures; Invited talk given at QG05, Cala Gonone (Italy), September 200

Black Holes and Causal Structure in Anti-de Sitter Isometric Spacetimes

The observation that the 2+1 dimensional BTZ black hole can be obtained as a quotient space of anti-de Sitter space leads one to ask what causal behaviour other such quotient spaces can display. In this paper we answer this question in 2+1 and 3+1 dimensions when the identification group has one generator. Among other things we find that there does not exist any 3+1 generalization of the rotating BTZ hole. However, the non-rotating generalization exists and exhibits some unexpected properties. For example, it turns out to be non-static and to possess a non-trivial apparent horizon.Comment: LaTeX, 22 pages, 10 postscript figures, uses epsf.te

The Rat and the Ship's Captain: A Dialogue-poem (muḥāwara) from the Gulf, with some comments on the social and literary-historical background of the genre

No abstrac

Probing linguistic change in Arabic vernaculars: a sociohistorical perspective

It is received wisdom in variationist sociolinguistics that linguistic and social factors go hand in hand in structuring variability in language and any consequent instances of language change. We address the complexity of such factors by exploring data from several Arabic dialects in the eastern Arab World. We demonstrate that language change does not always follow expected phonological trajectories, even in cases where older changes are reconstructed to have operated along so-called universal patterns. In our explanation of recent changes in these dialects, we emphasise the role of social motivations for language change and the interactions between these social constraints and purely linguistic ones. Our analysis of change is supported by historical accounts of variation and change in Arabic. We illustrate how general principles of sociolinguistic theory apply to the Arabic data and provide additional layers of sociolinguistic information that highlight the importance of diverse data for evaluating cross-linguistic generalisations

Clima Social Familiar Y Consumo De Alcohol En Adolescentes De La Institucion Educativa Secundaria Industrial De Quilcapunco, Putina - 2022.

Objetivo: Determinar la relación entre el clima social familiar y consumo de alcohol en estudiantes de la Institución Educativa Secundaria Industrial de Quilcapunco, 2022. Metodología: Investigación con enfoque cuantitativo, de tipo básico y correlacional, con diseño no experimental, de corte transversal. Se utilizó la técnica de la encuesta, cuyos instrumentos fueron: Escala de Clima Familiar (FES) y Cuestionario de consumo de alcohol (AUDIT). Para el procesamiento de datos se utilizó el software SPSS, y para la verificación de hipótesis la prueba estadística de la correlación de Speerman. Participantes: La muestra de estudio estuvo conformada por 60 estudiantes de tercero, cuarto y quinto año de la Institución Educativa Secundaria Industrial de Quilcapunco, quienes fueron seleccionados mediante un muestreo no probabilístico por conveniencia. Resultados: De forma general, el 40% de estudiantes presentó un clima social familiar “regular”, el 38% mostró un clima “bueno”, el 17% un clima “malo” y el 5% un clima familiar “muy bueno”. En relación a la variable consumo de alcohol, se determinó que el 82% de estudiantes tienen “bajo” consumo de alcohol, el 15% mostró un consumo “medio” y, finalmente, el 3% presentó un consumo “alto” de alcohol. Conclusiones: Se verificó que existe relación entre las variables clima social familiar y consumo de alcohol en estudiantes de la Institución Educativa Secundaria Industrial de Quilcapunco, con una significación bilateral de 0,00 y una correlación de -0,58

The nanosyntax of spatial deixis

This paper provides a fine-grained morphosyntactic analysis of spatial deixis. We propose that the universal core of spatial deixis is a three-way contrast: Proximal close to speaker', Medial close to hearer', and Distal far from speaker and hearer'. This system arises from three features merged as heads in a single universal functional sequence: Dx(3) > Dx(2) > Dx(1). The hierarchy is understood in terms of superset-subset relations, such that Proximal [Dx(1)] is a subset of Medial [Dx(2) [Dx(1)]], which in turn is a subset of Distal [Dx(3) [Dx(2) [Dx(1)]]]. Evidence comes from patterns of syncretism and morphological containment in the demonstrative systems of a number of genetically diverse languages. Regarding syncretisms, languages can show a transparent three-way morphological contrast, or some sort of syncretism: Medial/Proximal vs. Distal, Distal/Medial vs. Proximal, or a totally syncretic Distal/Medial/Proximal (i.e. a neutral demonstrative). These syncretisms entail that the features responsible for the Proximal and Medial readings be adjacent and that the features responsible for the Distal and Medial readings be adjacent in the fseq. Regarding containment, we show that Proximal can be structurally contained within Medial and that Medial can be structurally contained within Distal, meaning that Medial structures are larger than Proximal structures, and that Distal structures are larger than Medial structures, confirming our hierarchy. We show that these facts are naturally accounted for by nanosyntactic principles of spellout. We end the paper by accounting for potential counterexamples and other issues

Social integration and dialect divergence in coastal Palestine

The history of Palestine has caused communities to be displaced and relocated, entailing that speech communities have been dismantled and created anew. The coastal cities of Jaffa and Gaza exemplify this reality. This study analyzes speakers from Jaffa, some of whom remained there and others residing in Gaza as refugees. Through an examination of three variables, (ʕ), (AH), and (Q), we shed light on the effects of dialect contact while highlighting the link between dialect contact and identity formation and maintenance. All three variables are found to be in varied states of change as a result of contact with other varieties of Arabic, as well as with Modern Hebrew. We conclude that (Q), through its high social salience, works to create and maintain a sense of community identity for Jaffan refugees in Gaza at a time when the speech of the larger Jaffa community is undergoing substantial linguistic change

A cross dialectal view of the Arabic dative alternation

This paper is concerned with the syntax of ditransitive verbs in Arabic.We concentrate on the vernaculars, focussing in particular on three geographically spread dialects: Egyptian Cairene Arabic, the dominant vernacular in Egypt, Hijazi Arabic, spoken in Western Saudi Arabia and Maltese, a mixed language with a Magrebi/Siculo-Arabic stratum. We show that all three exhibit an alternation (the dative alternation) between a ditransitive ('double object') construction and a corresponding prepositional dative construction, and outline a number of differences between these constructions in the different varieties of Arabic. We consider the distribution of verbs exhibiting the dative alternation in the light of Ryding's (2011) observations concerning Modern Standard Arabic

Concomitant optic nerve transection and chorioretinitis sclopetaria

BACKGROUND: Optic nerve transection and chorioretinitis sclopetaria may occur following blunt ocular trauma. However, simultaneous occurrence has not yet been reported. We report the first case of concomitant optic nerve transection and chorioretinitis sclopetaria. CASE PRESENTATION: A 12- year- old boy with history of BB gun injury to his right eye was referred for loss of vision. His visual acuity was counting fingers at one meter in the right eye and with 3+ relative afferent pupillary defect (RAPD). On slit lamp examination, the right eye appeared normal except for 1+ vitreous reaction. Fundus examination of the right eye revealed a pale disc with superior retinal scar and diffuse submacular fibrosis compatible with chorioretinitis sclopetaria. Orbital CT- scans showed transection of the optic nerve by the BB gun pellet, which was lodged at the orbital apex. CONCLUSION: BB gun injury may cause concomitant optic nerve transection and chorioretinitissclopetaria