2,562 research outputs found
Hybrid Pixel Detector Development for the Linear Collider Vertex Tracker
In order to fully exploit the physics potential of the future high energy
e+e- linear collider, a Vertex Tracker able to provide particle track
extrapolation with very high resolution is needed. Hybrid Si pixel sensors are
an attractive technology due to their fast read-out capabilities and radiation
hardness. A novel pixel detector layout with interleaved cells has been
developed to improve the single point resolution. Results of the
characterisation of the first processed prototypes by electrostatic
measurements and charge collection studies are discussed.Comment: 5 pages, 1 figure, to appear in the Proceedings of the 9th Int.
Workshop on Vertex Detectors, Lake Michigan MI (USA), September~200
Artifacts with uneven sampling of red noise
The vast majority of sampling systems operate in a standard way: at each tick
of a fixed-frequency master clock a digitizer reads out a voltage that
corresponds to the value of some physical quantity and translates it into a bit
pattern that is either transmitted, stored, or processed right away. Thus
signal sampling at evenly spaced time intervals is the rule: however this is
not always the case, and uneven sampling is sometimes unavoidable.
While periodic or quasi-periodic uneven sampling of a deterministic signal
can reasonably be expected to produce artifacts, it is much less obvious that
the same happens with noise: here I show that this is indeed the case only for
long-memory noise processes, i.e., power-law noises with . The resulting artifacts are usually a nuisance although they can be
eliminated with a proper processing of the signal samples, but they could also
be turned to advantage and used to encode information.Comment: 5 figure
Teacher perspectives on the introduction of linguistics in the languages classroom: Evidence from a co-creation project on French, German and Spanish
Linguistics is conspicuously absent from language teaching in UK schools. A-level cultural topics cover a range of themes such as cyber-society, cultural heritage, and multiculturalism, but the approach taken to these topics is not informed by linguistics. In previous work (Sheehan et al. 2021), we have argued that this is an unfortunate omission not only because linguistics is appealing to many language students and perceived by them to be useful, but also because the existing cultural topics could be significantly enriched by the inclusion of the critical/analytical study of language itself (Corr et al. 2019). In this paper, we provide concrete examples of how linguistics can be integrated into the existing A-level curriculum for Modern Foreign Languages (MFL) in England and Wales. Reporting on a project in which teachers trialled linguistics materials co-created by us (a group of academics) and experienced languages teachers, we present evidence that linguistics materials are perceived to be both highly novel but nonetheless compatible with the existing A-level curriculum. Data from questionnaires and semi-structured interviews with participating teachers also shows that: (i) these new materials can be taught with little or no prior experience of linguistics; and (ii) adding linguistics materials to the curriculum leads to significant impacts on teacher and pupil attitudes towards language(s). Despite some challenges, which we also discuss, the results highlight again the great potential of linguistics as a component of language teaching and the contribution that it can make to the enrichment of the discipline
A classification of smooth embeddings of 3-manifolds in 6-space
We work in the smooth category. If there are knotted embeddings S^n\to R^m,
which often happens for 2m<3n+4, then no concrete complete description of
embeddings of n-manifolds into R^m up to isotopy was known, except for disjoint
unions of spheres. Let N be a closed connected orientable 3-manifold. Our main
result is the following description of the set Emb^6(N) of embeddings N\to R^6
up to isotopy.
The Whitney invariant W : Emb^6(N) \to H_1(N;Z) is surjective. For each u \in
H_1(N;Z) the Kreck invariant \eta_u : W^{-1}u \to Z_{d(u)} is bijective, where
d(u) is the divisibility of the projection of u to the free part of H_1(N;Z).
The group Emb^6(S^3) is isomorphic to Z (Haefliger). This group acts on
Emb^6(N) by embedded connected sum. It was proved that the orbit space of this
action maps under W bijectively to H_1(N;Z) (by Vrabec and Haefliger's
smoothing theory). The new part of our classification result is determination
of the orbits of the action. E. g. for N=RP^3 the action is free, while for
N=S^1\times S^2 we construct explicitly an embedding f : N \to R^6 such that
for each knot l:S^3\to R^6 the embedding f#l is isotopic to f.
Our proof uses new approaches involving the Kreck modified surgery theory or
the Boechat-Haefliger formula for smoothing obstruction.Comment: 32 pages, a link to http://www.springerlink.com added, to appear in
Math. Zei
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The cost of a primary care-based childhood obesity prevention intervention
Background: United States pediatric guidelines recommend that childhood obesity counseling be conducted in the primary care setting. Primary care-based interventions can be effective in improving health behaviors, but also costly. The purpose of this study was to evaluate the cost of a primary care-based obesity prevention intervention targeting children between the ages of two and six years who are at elevated risk for obesity, measured against usual care. Methods: High Five for Kids was a cluster-randomized controlled clinical trial that aimed to modify children’s nutrition and TV viewing habits through a motivational interviewing intervention. We assessed visit-related costs from a societal perspective, including provider-incurred direct medical costs, provider-incurred equipment costs, parent time costs and parent out-of-pocket costs, in 2011 dollars for the intervention (n = 253) and usual care (n = 192) groups. We conducted a net cost analysis using both societal and health plan costing perspectives and conducted one-way sensitivity and uncertainty analyses on results. Results: The total costs for the intervention group and usual care groups in the first year of the intervention were 64,522, 12,192 (95% CI [13,174]). The mean costs for the intervention and usual care groups were 255, 63 (95% CI [69]) per child, respectively, for a incremental difference of 191, $202]) per child. Children in the intervention group attended a mean of 2.4 of a possible 4 in-person visits and received 0.45 of a possible 2 counseling phone calls. Provider-incurred costs were the primary driver of cost estimates in sensitivity analyses. Conclusions: High Five for Kids was a resource-intensive intervention. Further studies are needed to assess the cost-effectiveness of the intervention relative to other pediatric obesity interventions. Trial registration ClinicalTrials.gov Identifier: NCT00377767
Early Implementation of THAM for ICP Control: Therapeutic Hypothermia Avoidance and Reduction in Hypertonics/Hyperosmotics
Background. Tromethamine (THAM) has been demonstrated to reduce intracranial pressure (ICP). Early consideration for THAM may reduce the need for other measures for ICP control. Objective. To describe 4 cases of early THAM therapy for ICP control and highlight the potential to avoid TH and paralytics and achieve reduction in sedation and hypertonic/hyperosmotic agent requirements. Methods. We reviewed the charts of 4 patients treated with early THAM for ICP control. Results. We identified 2 patients with aneurysmal subarachnoid hemorrhage (SAH) and 2 with traumatic brain injury (TBI) receiving early THAM for ICP control. The mean time to initiation of THAM therapy was 1.8 days, with a mean duration of 5.3 days. In all patients, after 6 to 12 hours of THAM administration, ICP stability was achieved, with reduction in requirements for hypertonic saline and hyperosmotic agents. There was a relative reduction in mean hourly hypertonic saline requirements of 89.1%, 96.1%, 82.4%, and 97.0% for cases 1, 2, 3, and 4, respectively, comparing pre-to post-THAM administration. Mannitol, therapeutic hypothermia, and paralytics were avoided in all patients. Conclusions. Early administration of THAM for ICP control could potentially lead to the avoidance of other ICP directed therapies. Prospective studies of early THAM administration are warranted
Association of Vitamin E Intake at Early Childhood with Alanine Aminotransferase Levels at Mid-Childhood
The extent to which vitamin E (alpha-tocopherol) intake early in childhood is associated with alanine aminotransferase (ALT) level later in childhood is unknown. The objective of this research is to test the hypothesis that higher alpha-tocopherol intake during early childhood is associated with lower odds of elevated ALT levels during mid-childhood, and to examine how body mass index (BMI) influences these relationships. We studied 528 children in Project Viva. Mothers reported child dietary intake at early childhood visits (median 3.1 years) using a validated food frequency questionnaire. At mid-childhood (median 7.6 years), we collected child blood and anthropometric data. The main outcome was elevated sex-specific mid-childhood ALT level (≥ 22.1 units/liter for females and ≥ 25.8 units/liter for males). In multivariable logistic regression models, we assessed the association of energy-adjusted alpha-tocopherol intake with ALT levels, adjusting for child age, sex, race/ethnicity, diet, and age-adjusted, sex-specific BMIz at mid-childhood. Among children in this study, 48% were female, 63% were non-Hispanic white, 19% were non-Hispanic black, and 4% Hispanic/Latino. Mean alpha-tocopherol intake was 3.7±1.0 mg/day (range 1.4-9.2) at early childhood. At mid-childhood, mean BMIz was 0.41±1.0 units and 22% had an elevated ALT level. In multivariable-adjusted logistic regression models, children with higher early childhood vitamin E intake had lower odds of elevated mid-childhood ALT [adjusted odds ratio (AOR) 0.62 (95% CI: 0.39-0.99)] for quartiles 2-4 compared with the lowest quartile of intake. Findings persisted after accounting for early childhood diet [0.62 (0.36, 1.08)] and were strengthened after additionally accounting for mid-childhood BMIz [0.56 (0.32, 0.99)].
Conclusion: In this cohort, higher early childhood intake of alpha-tocopherol was associated with lower odds of elevated mid-childhood ALT level
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