Quantum Multiobservable Control

We present deterministic algorithms for the simultaneous control of an arbitrary number of quantum observables. Unlike optimal control approaches based on cost function optimization, quantum multiobservable tracking control (MOTC) is capable of tracking predetermined homotopic trajectories to target expectation values in the space of multiobservables. The convergence of these algorithms is facilitated by the favorable critical topology of quantum control landscapes. Fundamental properties of quantum multiobservable control landscapes that underlie the efficiency of MOTC, including the multiobservable controllability Gramian, are introduced. The effects of multiple control objectives on the structure and complexity of optimal fields are examined. With minor modifications, the techniques described herein can be applied to general quantum multiobjective control problems.Comment: To appear in Physical Review

Common internal parasites of swine

Swine performance can be seriously affected by internal parasites of various kinds. Even light infestations of some internal parasites can cause unthriftiness and poor performance. In a survey of internal parasites on swine farms in Missouri, a high percentage of all farms had one or more kinds of parasites. Animals on about half of these farms had levels high enough to need treatment. Producers can reduce loss from parasites by planned prevention programs and use of improved treatment techniques.John C. Rea (Department of Animal Husbandry, College of Agriculture), Bonnard Moseley (School of Veterinary Medicine)Revised 1/7

Time-optimal Unitary Operations in Ising Chains II: Unequal Couplings and Fixed Fidelity

We analytically determine the minimal time and the optimal control laws required for the realization, up to an assigned fidelity and with a fixed energy available, of entangling quantum gates ($\mathrm{CNOT}$) between indirectly coupled qubits of a trilinear Ising chain. The control is coherent and open loop, and it is represented by a local and continuous magnetic field acting on the intermediate qubit. The time cost of this local quantum operation is not restricted to be zero. When the matching with the target gate is perfect (fidelity equal to one) we provide exact solutions for the case of equal Ising coupling. For the more general case when some error is tolerated (fidelity smaller than one) we give perturbative solutions for unequal couplings. Comparison with previous numerical solutions for the minimal time to generate the same gates with the same Ising Hamiltonian but with instantaneous local controls shows that the latter are not time-optimal.Comment: 11 pages, no figure

The concordance of MRI and arthroscopy in traumatic meniscal lesions in children

SummaryIntroductionTraumatic meniscal lesions in children must be diagnosed quickly and efficiently as a priority in order to conserve the meniscus and safeguard the future of the knee. They are often isolated and difficult to identify clinically. In the diagnostic work up stage, an excessive resort to diagnostic arthroscopy has given way to increasing use of MRI by radiologists without pediatric specialization. The present study examined the agreement between MRI aspect and arthroscopic exploration in traumatic meniscal lesions in children.Patients and methodsSixty-nine knees in children aged 9 to 16 years having undergone MRI followed by arthroscopy for knee trauma between 1995 and 2008 were included in a retrospective design. Discoid meniscus was excluded. Files were reviewed by a single clinician and MRI scans by a radiologist specialized in pediatric pathology. Cases of epiphyseal fusion were excluded. All files were analyzable. Agreement with arthroscopic findings as reference was assessed for presence, location and type of meniscal lesion.ResultsOverall agreement with arthroscopy was respectively 78% and 82% on first and second MRI readings: 77% and 80% for the medial, and 78% and 84% for the lateral meniscus. On the first reading, there were 13 false positives for the medial and 5 for the lateral meniscus, versus 9 and 0 respectively on second reading. Overall sensitivity was 70% on first reading and 64% on second, and overall specificity 81% and 90%, respectively.DiscussionThe present results, in line with the literature, may appear encouraging, but hide considerable disparity between analysis of the medial and of the lateral meniscus: MRI overestimated medial and underestimated lateral meniscus lesions.ConclusionMRI serves only as a support and does not provide sure diagnosis of meniscus lesion. Interpretation should take account of the clinical examination and the pediatric orthopedic specialist's experience.Level of evidenceLevel IV, retrospective study

The Eukaryotic Promoter Database (EPD): recent developments

The Eukaryotic Promoter Database (EPD) is an annotated non-redundant collection of eukaryotic POL II promoters, for which the transcription start site has been determined experimentally. Access to promoter sequences is provided by pointers to positions in nucleotide sequence entries. The annotation part of an entry includes description of the initiation site mapping data, cross-references to other databases, and bibliographic references. EPD is structured in a way that facilitates dynamic extraction of biologically meaningful promoter subsets for comparative sequence analysis. Recent efforts have focused on exhaustive cross-referencing to the EMBL nucleotide sequence database, and on the improvement of the WWW-based user interfaces and data retrieval mechanisms. EPD can be accessed at http://www.epd.isb-sib.c

Geometric Approach to Pontryagin's Maximum Principle

Since the second half of the 20th century, Pontryagin's Maximum Principle has been widely discussed and used as a method to solve optimal control problems in medicine, robotics, finance, engineering, astronomy. Here, we focus on the proof and on the understanding of this Principle, using as much geometric ideas and geometric tools as possible. This approach provides a better and clearer understanding of the Principle and, in particular, of the role of the abnormal extremals. These extremals are interesting because they do not depend on the cost function, but only on the control system. Moreover, they were discarded as solutions until the nineties, when examples of strict abnormal optimal curves were found. In order to give a detailed exposition of the proof, the paper is mostly self\textendash{}contained, which forces us to consider different areas in mathematics such as algebra, analysis, geometry.Comment: Final version. Minors changes have been made. 56 page

Does prenatal diagnosis modify neonatal treatment and early outcome of children with esophageal atresia?

OBJECTIVE: Our study aimed at (1) evaluating neonatal treatment and outcome of neonates with either a prenatal or a postnatal diagnosis of esophageal atresia (EA) and (2) analyzing the impact of prenatal diagnosis on outcome based on the type of EA. STUDY DESIGN: We conducted a population-based study using data from the French National Register for infants with EA born from 2008-2010. We compared prenatal, maternal, and neonatal characteristics among children with prenatal vs postnatal diagnosis and EA types I and III. We defined a composite variable of morbidity (anastomotic esophageal leaks, recurrent fistula, stenosis) and death at 1 year. RESULTS: Four hundred sixty-nine live births with EA were recorded with a prenatal diagnosis rate of 24.3%; 82.2% of EA type I were diagnosed prenatally compared with 17.9% of EA type III (P < .001). Transfer after birth was lower in case of prenatal diagnosis (25.6% vs 82.5%; P < .001). The delay between birth and first intervention did not differ significantly among groups. The defect size was longer among the prenatal diagnosis group (2.61 vs 1.48 cm; P < .001). The composite variables were higher in prenatal diagnosis subset (44% vs 27.6%; P = .003) and in EA type I than in type III (58.1% vs 28.3%; P < .001). CONCLUSION: Despite the excellent survival rate of EA, cases with antenatal detection have a higher morbidity rate related to the EA type (type I and/or long gap). Even though it does not modify neonatal treatment and the 1-year outcome, prenatal diagnosis allows antenatal parental counselling and avoids postnatal transfers

Saturation of a spin 1/2 particle by generalized Local control

We show how to apply a generalization of Local control design to the problem of saturation of a spin 1/2 particle by magnetic fields in Nuclear Magnetic Resonance. The generalization of local or Lyapunov control arises from the fact that the derivative of the Lyapunov function does not depend explicitly on the control field. The second derivative is used to determine the local control field. We compare the efficiency of this approach with respect to the time-optimal solution which has been recently derived using geometric methods.Comment: 12 pages, 4 figures, submitted to new journal of physics (2011