Simplified open repair for anterior chest wall deformities. Analysis of results in 205 patients

SummaryIntroductionPectus deformities are the most frequently seen congenital thoracic wall anomalies. The cause of these conditions is thought to be abnormal elongation of the rib cartilages. We here report our clinical experience and the results of a sternochondroplasty procedure based on the subperichondrial resection of the elongated cartilages.HypothesisThis technique is a valuable surgical strategy to treat the wide variety of pectus deformities.Patients and methodsDuring the period from October 2001 through September 2009, 205 adult patients (171 men and 34 women) underwent pectus excavatum (181), carinatum (19) or arcuatum (5) repair. The patients’ pre and postoperative data were collected using a computerized database, and the results were assessed with a minimum 2-year follow-up.ResultsThe postoperative morbidity rate was minimal and the mortality was nil. The surgeon graded cosmetic results as excellent (72.5%), good (25%) or fair (2.5%), while patients reported better results. Patients with pectus excavatum were found to have much more patent foramen ovale (PFO) than the normal adult population, which occluded after the procedure in 61% of patients, and significant improvement was found in exercise cardiopulmonary function and exercise tolerance at the 1-year follow-up.DiscussionOur sternochondroplasty technique based on the subperichondrial resection of the elongated cartilages allows satisfactory repair of both pectus excavatum and sternal prominence. It is a safe procedure that might improve the effectiveness of surgical therapy in patients with pectus deformities.Level of evidenceLevel IV. Retrospective study

A transactional stress theory of global work demands : A challenge, hindrance, or both?

We integrate research on global work demands (Shaffer et al., 2012) with transactional stress theory to examine both the harmful and beneficial effects of three global work demands—international travel, cognitive flexibility, and nonwork disruption—for employees engaged in global work. We propose that global work demands have indirect, and conditional, effects on burnout and work-to-family conflict (WFC), as well as thriving and work–family enrichment, through employees’ appraisals that their global work is both hindering and challenging, respectively. We tested the hypotheses with a matched sample of 229 global employees and their spouses. We found that cognitive flexibility demands are related to harmful and beneficial outcomes: It increases WFC through hindrance appraisals of the global work, but also increases thriving through challenge appraisals. In comparison, international travel demands have only beneficial outcomes, such that it positively related to employee thriving through challenge appraisals, but only among employees working in jobs that have fewer nonwork disruption demands. Finally, nonwork disruption demands had only harmful effects in that it positively related to burnout and WFC through hindrance appraisals. Exploratory analyses also revealed that nonwork disruption demands negatively related to employee thriving, through challenge appraisals, when employees experienced lower levels of cognitive flexibility demands. These findings contribute to our understanding of how employees may react to their global work demands and to the transactional theory of stress by providing a more nuanced understanding of when and why job demands contribute to appraisals that work is hindering and/or challenging.© 2022, American Psychological Association. This paper is not the copy of record and may not exactly replicate the final, authoritative version of the article. Please do not copy or cite without authors' permission. The final article will be available, upon publication, via its DOI: 10.1037/apl0001009fi=vertaisarvioitu|en=peerReviewed

Experimental investigation of the edge states structure at fractional filling factors

We experimentally study electron transport between edge states in the fractional quantum Hall effect regime. We find an anomalous increase of the transport across the 2/3 incompressible fractional stripe in comparison with theoretical predictions for the smooth edge potential profile. We interpret our results as a first experimental demonstration of the intrinsic structure of the incompressible stripes arising at the sample edge in the fractional quantum Hall effect regime.Comment: 5 pages, 5 figures included. Submitted to JETP Letter

Concave Plasmonic Particles: Broad-Band Geometrical Tunability in the Near Infra-Red

Optical resonances spanning the Near and Short Infra-Red spectral regime were exhibited experimentally by arrays of plasmonic nano-particles with concave cross-section. The concavity of the particle was shown to be the key ingredient for enabling the broad band tunability of the resonance frequency, even for particles with dimensional aspect ratios of order unity. The atypical flexibility of setting the resonance wavelength is shown to stem from a unique interplay of local geometry with surface charge distributions

The OPERA experiment Target Tracker

The main task of the Target Tracker detector of the long baseline neutrino oscillation OPERA experiment is to locate in which of the target elementary constituents, the lead/emulsion bricks, the neutrino interactions have occurred and also to give calorimetric information about each event. The technology used consists in walls of two planes of plastic scintillator strips, one per transverse direction. Wavelength shifting fibres collect the light signal emitted by the scintillator strips and guide it to both ends where it is read by multi-anode photomultiplier tubes. All the elements used in the construction of this detector and its main characteristics are described.Comment: 25 pages, submitted to Nuclear Instrument and Method

Winner-take-all selection in a neural system with delayed feedback

We consider the effects of temporal delay in a neural feedback system with excitation and inhibition. The topology of our model system reflects the anatomy of the avian isthmic circuitry, a feedback structure found in all classes of vertebrates. We show that the system is capable of performing a `winner-take-all' selection rule for certain combinations of excitatory and inhibitory feedback. In particular, we show that when the time delays are sufficiently large a system with local inhibition and global excitation can function as a `winner-take-all' network and exhibit oscillatory dynamics. We demonstrate how the origin of the oscillations can be attributed to the finite delays through a linear stability analysis.Comment: 8 pages, 6 figure

Non-renewal statistics in the catalytic activity of enzyme molecules at mesoscopic concentrations

Recent fluorescence spectroscopy measurements of single-enzyme kinetics have shown that enzymatic turnovers form a renewal stochastic process in which the inverse of the mean waiting time between turnovers follows the Michaelis-Menten equation. Under typical physiological conditions, however, tens to thousands of enzymes react in catalyzing thousands to millions of substrates. We study enzyme kinetics at these physiologically relevant conditions through a master equation including stochasticity and molecular discreteness. From the exact solution of the master equation we find that the waiting times are neither independent nor are they identically distributed, implying that enzymatic turnovers form a non-renewal stochastic process. The inverse of the mean waiting time shows strong departures from the Michaelis-Menten equation. The waiting times between consecutive turnovers are anti-correlated, where short intervals are more likely to be followed by long intervals and vice versa. Correlations persist beyond consecutive turnovers indicating that multi-scale fluctuations govern enzyme kinetics.Comment: 5 pages, 4 figures, to appear in Physical Review Letter