Event Weighted Tests for Detecting Periodicity in Photon Arrival Times

This paper treats the problem of detecting periodicity in a sequence of photon arrival times, which occurs, for example, in attempting to detect gamma-ray pulsars. A particular focus is on how auxiliary information, typically source intensity, background intensity, and incidence angles and energies associated with each photon arrival should be used to maximize the detection power. We construct a class of likelihood-based tests, score tests, which give rise to event weighting in a principled and natural way, and derive expressions quantifying the power of the tests. These results can be used to compare the efficacies of different weight functions, including cuts in energy and incidence angle. The test is targeted toward a template for the periodic lightcurve, and we quantify how deviation from that template affects the power of detection

Thermopower of an SU(4) Kondo resonance under an SU(2) symmetry-breaking field

We calculate the thermopower of a quantum dot described by two doublets hybridized with two degenerate bands of two conducting leads, conserving orbital (band) and spin quantum numbers, as a function of the temperature $T$ and a splitting $\delta$ of the quantum dot levels which breaks the SU(4) symmetry. The splitting can be regarded as a Zeeman (spin) or valley (orbital) splitting. We use the non-crossing approximation (NCA), the slave bosons in the mean-field approximation (SBMFA) and also the numerical renormalization group (NRG) for large $\delta$. The model describes transport through clean C nanotubes %with weak disorder and in Si fin-type field effect transistors, under an applied magnetic field. The thermopower as a function of temperature $S(T)$ displays two dips that correspond to the energy scales given by the Kondo temperature $T_K$ and $\delta$ and one peak when $k_BT$ reaches the charge-transfer energy. These features are much more pronounced than the corresponding ones in the conductance, indicating that the thermopower is a more sensitive probe of the electronic structure at intermediate or high energies. At low temperatures ($T \ll T_K$) $T_K S(T)/T$ is a constant that increases strongly near the degeneracy point $\delta=0$. We find that the SBMFA fails to provide an accurate description of the thermopower for large $\delta$. Instead, a combination of Fermi liquid relations with the quantum-dot occupations calculated within the NCA gives reliable results for $T \ll T_K$.Comment: 8 pages, 7 figure

Fijación externa en las fracturas-luxaciones centrales de cadera: a propósito de 3 casos

Se presentan tres casos de fractura-luxación central de cadera tratados mediante estabilización y reducción progresiva con fijación externa. Las ventajas de este tratamiento con respecto al tratamiento conservador o quirúrgico son la estabilización inmediata y la sencillez de realización. Los resultados de fijación externa obtenidos en estos pacientes demuestran una rehabilitación y deambulación precoz e independiente. La recuperación clínica y funcional fue satisfactoria en dos casos. En otro caso, con mala reducción quirúrgica previa, el resultado fue pobre.Three cases of central fracture-dislocation of the hip treated by stabilization and progressive reduction by means of external fixation are presented. The advantages of this procedure over the conservative or even the surgical treatment are the early stabilization and the fact that the technique is a step-forward procedure. The results obtained in these patients with external fixation of the hip led to a good rehabilitation and to an early independent ambulation. The clinical and functional recovery of these patients was satisfactory in two cases. In other with previous failed open reduction the result was poor

Explaining Aviation Safety Incidents Using Deep Temporal Multiple Instance Learning

Although aviation accidents are rare, safety incidents occur more frequently and require a careful analysis to detect and mitigate risks in a timely manner. Analyzing safety incidents using operational data and producing event-based explanations is invaluable to airline companies as well as to governing organizations such as the Federal Aviation Administration (FAA) in the United States. However, this task is challenging because of the complexity involved in mining multi-dimensional heterogeneous time series data, the lack of time-step-wise annotation of events in a flight, and the lack of scalable tools to perform analysis over a large number of events. In this work, we propose a precursor mining algorithm that identifies events in the multidimensional time series that are correlated with the safety incident. Precursors are valuable to systems health and safety monitoring and in explaining and forecasting safety incidents. Current methods suffer from poor scalability to high dimensional time series data and are inefficient in capturing temporal behavior. We propose an approach by combining multiple-instance learning (MIL) and deep recurrent neural networks (DRNN) to take advantage of MIL's ability to learn using weakly supervised data and DRNN's ability to model temporal behavior. We describe the algorithm, the data, the intuition behind taking a MIL approach, and a comparative analysis of the proposed algorithm with baseline models. We also discuss the application to a real-world aviation safety problem using data from a commercial airline company and discuss the model's abilities and shortcomings, with some final remarks about possible deployment directions

Importance of species‐specific antigens in the serodiagnosis of Chlamydia trachomatis reactive arthritis

Objectives. To determine the most sensitive and specific method of anti‐Chlamydia antibody measurement for the serodiagnosis of Chlamydia trachomatis reactive arthritis. Methods. Immunoblotting, enzyme‐linked immunosorbent assays using six synthetic peptides or recombinant antigens and a microimmunofluorescence test were used to determine the presence of IgG, IgM and IgA in serum samples from 17 patients with C. trachomatis reactive arthritis. Twenty patients with other inflammatory arthropathies without evidence of urogenital C. trachomatis infection were used as controls. Results. The best association of sensitivity (76%) and specificity (85%) was obtained when IgG and/or IgA reactivity to two species‐specific antigens was determined. These antigens were synthetic peptides, derived from species‐specific epitopes in the variable domain IV of the major outer membrane protein (MOMP) (Labsystems, Finland) and recombinant polypeptide encoded by open reading frame 3 of the plasmid (pgp3). Conclusions. IgG and/or IgA anti‐MOMP‐derived peptides and anti‐pgp3 could be useful for the diagnosis of probable C. trachomatis reactive arthriti

Parent-child interaction in Nigerian families: conversation analysis, context and culture

This paper uses a conversation analysis (CA) approach to explore parent child interaction (PCI) within Nigerian families. We illustrate how speech and language therapists (SLTs), by using CA, can tailor recommendations according to the interactional style of each individual family that are consonant with the family’s cultural beliefs. Three parent-child dyads were videoed playing and talking together in their home environments. The analysis uncovered a preference for instructional talk similar to that used in the classroom. Closer examination revealed that this was not inappropriate when considering the context of the activities and their perceived discourse role. Furthermore, this was not necessarily at the expense of responsivity or semantic contingency. The preference for instructional talk appeared to reflect deeply held cultural beliefs about the role of adults and children within the family and it is argued that the cultural paradigm is vitally important to consider when evaluating PCI. Given a potential risk that such young children may be vulnerable in terms of language difficulties, we offer an example of how PCI can be enhanced to encourage language development without disrupting the naturally occurring talk or the underlying purpose of the interaction

Escoliosis congénitas causadas por hemivertebras

Presentamos un estudio retrospectivo de 26 pacientes diagnosticados de escoliosis congénitas causadas por hemivertebras, liemos analizado la evolución de las curvas según el tipo de hemivértebra, su localización y el tratamiento recibido. Se han obtenido los peores resultados en las niñas, cuando el diagnóstico se realizó después de los 10 años de edad, en las curvas localizadas en la región toracolumbar, en las hemivértebras múltiples y, dentro de ellas, en las unilaterales segmentadas no adyacentes y en los pacientes tratados ortopédicamente.A retrospective study of 26 patients with congenital scoliosis due to hemivertebra was conducted. Curve progression was analysed regarding the type of hemivertebra, its localization, and the applied treatment. The worst results were found in girls, in cases who were diagnosed with more than to years of age, in thoraco-lumbar curves, in multiple hemivertebra, especially in non-adjacent segmented unilateral hemivertebra and, finally, in patients treated with orthopaedic methods

Expressiveness modulo Bisimilarity of Regular Expressions with Parallel Composition (Extended Abstract)

The languages accepted by finite automata are precisely the languages denoted by regular expressions. In contrast, finite automata may exhibit behaviours that cannot be described by regular expressions up to bisimilarity. In this paper, we consider extensions of the theory of regular expressions with various forms of parallel composition and study the effect on expressiveness. First we prove that adding pure interleaving to the theory of regular expressions strictly increases its expressiveness up to bisimilarity. Then, we prove that replacing the operation for pure interleaving by ACP-style parallel composition gives a further increase in expressiveness. Finally, we prove that the theory of regular expressions with ACP-style parallel composition and encapsulation is expressive enough to express all finite automata up to bisimilarity. Our results extend the expressiveness results obtained by Bergstra, Bethke and Ponse for process algebras with (the binary variant of) Kleene's star operation.Comment: In Proceedings EXPRESS'10, arXiv:1011.601

What chemical species are responsible for new particle formation and growth in the Netherlands? A hybrid positive matrix factorization (PMF) analysis using aerosol composition (ACSM) and size (SMPS)

Aerosol formation acts as a sink for gas-phase atmospheric species that controls their atmospheric lifetime and environmental effects. To investigate aerosol formation and evolution in the Netherlands, a hybrid positive matrix factorization (PMF) analysis was conducted using observations from May, June, and September 2021 collected in the rural site of Cabauw in the central part of the Netherlands. The hybrid input matrix consists of the full organic mass spectrum acquired from a time-of-flight aerosol chemical speciation monitor (ToF-ACSM), ACSM inorganic species concentrations, and binned particle size distribution concentrations from a scanning mobility particle sizer (SMPS). These hybrid PMF analyses discerned four factors that describe aerosol composition variations: two size-driven factors that are related to new particle formation (NPF) and growth (F4 and F3), as well as two bulk factors driven by composition, not size (F2 and F1). The distribution of chemical species across these factors shows that different compounds are responsible for nucleation and growth of new particles. The smallest-diameter size factor (F4) contains ammonium sulfate and organics and typically peaks during the daytime. Newly formed particles, represented by F4, are mainly correlated with wind from the southwesterly-westerly and easterly sectors that transport sulfur oxides (SOx), ammonia (NH3), and organic precursors to Cabauw. As the particles grow from F4 to F3 and to bulk factors, nitrate and organics play an increasing role, and the particle loading diurnal cycle shifts from daytime to a nighttime maximum. Greater organics availability makes secondary organic aerosol (SOA) more influential in summertime aerosol growth, principally due to volatility differences produced by seasonal variation in photooxidation and temperature.</p