Covariant Phase Observables in Quantum Mechanics

The aim of this thesis is to present a solution to the quantum phase problem of the single-mode optical field. The solution is based on the use of phase shift covariant normalized positive operator measures. These measures describe realistic direct coherent state phase measurements such as the phase measurement schemes based on eight-port homodyne detection or heterodyne detection. The structure of covariant operator measures and, more generally, covariant sesquilinear form measures is analyzed in this work. Four different characterizations for phase shift covariant normalized positive operator measures are presented. The canonical covariant operator measure is definded and its properties are studied. Finally, some other suggested phase theories are introduced to investigate their connections to the covariant sesquilinear form measures.

In vivo loading increases mechanical properties of scaffold by affecting bone formation and bone resorption rates.

A successful bone tissue engineering strategy entails producing bone-scaffold constructs with adequate mechanical properties. Apart from the mechanical properties of the scaffold itself, the forming bone inside the scaffold also adds to the strength of the construct. In this study, we investigated the role of in vivo cyclic loading on mechanical properties of a bone scaffold. We implanted PLA/β-TCP scaffolds in the distal femur of six rats, applied external cyclic loading on the right leg, and kept the left leg as a control. We monitored bone formation at 7 time points over 35 weeks using time-lapsed micro-computed tomography (CT) imaging. The images were then used to construct micro-finite element models of bone-scaffold constructs, with which we estimated the stiffness for each sample at all time points. We found that loading increased the stiffness by 60% at 35 weeks. The increase of stiffness was correlated to an increase in bone volume fraction of 18% in the loaded scaffold compared to control scaffold. These changes in volume fraction and related stiffness in the bone scaffold are regulated by two independent processes, bone formation and bone resorption. Using time-lapsed micro-CT imaging and a newly-developed longitudinal image registration technique, we observed that mechanical stimulation increases the bone formation rate during 4-10 weeks, and decreases the bone resorption rate during 9-18 weeks post-operatively. For the first time, we report that in vivo cyclic loading increases mechanical properties of the scaffold by increasing the bone formation rate and decreasing the bone resorption rate.

Assistance circulatoire chronique: le point en 2013 [Long-term mechanical circulatory support: where do we stand in 2013?].

With the advent of new technologies, experience with long-term mechanical circulatory support (MCS) is rapidly growing. Candidates to MCS are selected based on concepts, strategies and classifications that are specific to this indication. As results drastically improve, supported by stronger scientific evidence, the trend is towards earlier implantation. An adequate pre-implant follow-up is mandatory in order to avoid missing the best window of opportunity for implantation. While on chronic support, the hemodynamic profile of patients with continuous-flow ventricular assist devices is unique and remarkably influenced by the hydration status. Optimal management of these patients from the pre-implant phase to the long-term support phase requires a multidisciplinary approach that is similar to that already long validated for organ transplantation.

Influence of the quality of nursing on the duration of weaning from mechanical ventilation in patients with chronic obstructive pulmonary disease.

OBJECTIVE: To evaluate the influence of nursing on the duration of weaning from mechanical ventilation in patients with chronic obstructive pulmonary disease. DESIGN: Data were collected prospectively over a 1-yr period (study year) and compared with previously collected prospective data recorded in our chronic obstructive pulmonary disease database during a 5-yr period. SETTING: The medical intensive care unit (ICU) of a university hospital. PATIENTS: Eighty-seven patients with chronic obstructive pulmonary disease. Fifteen patients had chronic obstructive pulmonary disease that required mechanical ventilation for acute exacerbation of their disease (study year), and 72 were patients with chronic obstructive pulmonary disease from the previously collected data. INTERVENTIONS: The ICU course (duration of mechanical ventilation, mortality) was recorded, as well as several respiratory parameters (pulmonary function tests and arterial blood gases in stable conditions, and nutritional status), and they were compared with an "index of nursing." MEASUREMENTS AND MAIN RESULTS: We developed an "index of nursing", comparing the effective workforce of the nurses (number and qualifications) with the ideal workforce required by the number of patients and the severity of their diseases. A value of 1.0 represented a perfect match between the needed and the effectively present nurses, whereas a lesser value signified a diminished available workforce. This index was compared with the complications and duration of weaning from mechanical ventilation. During the first 5 yrs, the duration of mechanical ventilation increased progressively from 7.3 +/- 8.0 to 38.2 +/- 25.8 days (p = .006). A significant inverse correlation between the duration of mechanical ventilation and the nursing index (p = .025) was found. In the sixth comparative year, the number of nurses increased (nursing index = 1.05) and the duration of mechanical ventilation decreased to 9.9 +/- 13 days (p < .001, yr 5 vs. yr 6). CONCLUSIONS: The quality of nursing appears to be a measurable and critical factor in the weaning from mechanical ventilation of patients with chronic obstructive pulmonary disease. Below a threshold in the available workforce of ICU nurses, the weaning duration of patients with chronic obstructive pulmonary disease increases dramatically. Therefore, very close attention should be given to the education and number of ICU nurses.

Biomechanical characterization and in vitro mechanical injury of elderly human femoral head cartilage: comparison to adult bovine humeral head cartilage.

OBJECTIVES: In vitro mechanical injury of articular cartilage is useful to identify events associated with development of post-traumatic osteoarthritis (OA). To date, many in vitro injury models have used animal cartilage despite the greater clinical relevance of human cartilage. We aimed to characterize a new in vitro injury model using elderly human femoral head cartilage and compare its behavior to that of an existing model with adult bovine humeral head cartilage. DESIGN: Mechanical properties of human and bovine cartilage disks were characterized by elastic modulus and hydraulic permeability in radially confined axial compression, and by Young's modulus, Poisson's ratio, and direction-dependent radial strain in unconfined compression. Biochemical composition was assessed in terms of tissue water, solid, and glycosaminoglycan (GAG) contents. Responses to mechanical injury were assessed by observation of macroscopic superficial tissue cracks and histological measurements of cell viability following single injurious ramp loads at 7 or 70%/s strain rate to 3 or 14 MPa peak stress. RESULTS: Confined compression moduli and Young's moduli were greater in elderly human femoral cartilage vs adult bovine humeral cartilage whereas hydraulic permeability was less. Radial deformations of axially compressed explant disks were more anisotropic (direction-dependent) for the human cartilage. In both cartilage sources, tissue cracking and associated cell death during injurious loading was common for 14 MPa peak stress at both strain rates. CONCLUSION: Despite differences in mechanical properties, acute damage induced by injurious loading was similar in both elderly human femoral cartilage and adult bovine humeral cartilage, supporting the clinical relevance of animal-based cartilage injury models. However, inherent structural differences such as cell density may influence subsequent cell-mediated responses to injurious loading and affect the development of OA.

Gross – to – Net Payroll Calculation Program Human Resources Information System (HRIS), 2000

Gross-to-Net is a payroll calculator modeled after the actual payroll calculation used for state employees’ paychecks. This calculator can be used to project changes in net pay when there are changes in pay amounts, hours worked, mandatory and voluntary deductions, including all pre-tax deductions such as retirement, insurances, deferred compensation or flexible spending plans. Federal and state tax withholding, retirement rates, OASDI and Medicare (FICA) are calculated using current rates.

New record of Pterotaenia fasciata (Wiedemann) (Diptera, Ulidiidae) in Brazil, a probably mechanical vector of enteric bacteria

Pterotaenia fasciata is commonly recorded in rural areas in Argentina, but during a Diptera survey study developed in a reservoir which retains storm water from polluted canals in an urban area of Taboão da Serra municipality, SP, Brazil, we could capture P. fasciata adults. Enteric bacteria Escherichia coli T. Escherich, 1885 and Proteus sp. were isolated from P. fasciata collected in traps inside the reservoir and around it. Fecal coliforms and E. coli were found in the water of the reservoir. These records suggest that a high abundance of this species at urban areas with inadequate sewage canals should reveal these muscoid dipterans as mechanical vectors of enteric bacteria.

Measuring mechanical impedance in clayey gravelly soils

Mechanical impedance of clayey and gravelly soils is often needed to interpret experimental results from tillage and other field experiments. Its measurement is difficult with manual and hydraulic penetrometers, which often bend or break in such soils. The purpose of this study was to evaluate the feasibility of a hand-operated "Stolf" impact penetrometer to measure mechanical impedance (soil resistance). The research was conducted in Raleigh, North Carolina, USA (35º 45'N, 78º 42'W, elevation 75 m). Corn was planted on April 19, 1991. Penetrometer measurements were taken on May 10, 1991, in 5 cm intervals to 60 cm at 33 locations on a transect perpendicular to the corn rows in each of four tillage treatments. The data permitted three-dimensional displays showing how mechanical impedance changed with depth and distance along the transect. The impact penetrometer proved to be a useful tool to collect quantitative mechanical impedance data on "hard" clayey and/or gravelly soils which previously were difficult to reliably quantify.

MSISpIC: A Probabilistic Scan Matching Algorithm Using a Mechanical Scanned Imaging Sonar

This paper compares two well known scan matching algorithms: the MbICP and the pIC. As a result of the study, it is proposed the MSISpIC, a probabilistic scan matching algorithm for the localization of an Autonomous Underwater Vehicle (AUV). The technique uses range scans gathered with a Mechanical Scanning Imaging Sonar (MSIS), and the robot displacement estimated through dead-reckoning with the help of a Doppler Velocity Log (DVL) and a Motion Reference Unit (MRU). The proposed method is an extension of the pIC algorithm. Its major contribution consists in: 1) using an EKF to estimate the local path traveled by the robot while grabbing the scan as well as its uncertainty and 2) proposing a method to group into a unique scan, with a convenient uncertainty model, all the data grabbed along the path described by the robot. The algorithm has been tested on an AUV guided along a 600m path within a marina environment with satisfactory results

Wechsel von einem mechanischen Mikrokeratom auf einen Femtosekunden-Laser zur Korrektur von Astigmatismus mittels LASIK: klinische Ergebnisse einer retrospektiven, konsekutiven Vergleichsstudie Moving from a Mechanical Microkeratome to a Femtosecond Laser for LASIK to Correct Astigmatic Patients: Clinical Outcomes of a Retrospective, Consecutive, Comparative Study.

Background: To evaluate outcomes after optimized laser in situ keratomileusis (LASIK) for astigmatism correction with flap created by a mechanical microkeratome or a femtosecond laser. Patients and Methods: In this retrospective study, a total of 102 eyes of 71 consecutive patients were enrolled undergoing optimized LASIK treatments using the Allegretto laser system (WaveLight Laser Technologie AG, Erlangen, Germany). A mechanical microkeratome for flap creation was used (One Use, Moria®) in 46 eyes (31 patients, spherical equivalent [SE] -4.44 D ± 2.4) and a femtosecond laser was used (LDV, Ziemer®) in 56 eyes (40 patients, spherical equivalent [SE] -3.07 D ± 3.3). The two groups were matched for inclusion criteria and were operated under similar conditions by the same surgeon. Results: Overall, the preoperative spherical equivalent was -9.5 diopters (D) to +3.37 D; the preoperative manifest astigmatism was between -1.5 D and -3.5 D. At 6 months postoperatively, the mean postoperative uncorrected distance visual acuity (UDVA) was 0.93 ± 0.17 (range 0.4 to 1.2) in the Moria group and 1.0 ± 0.21 (range 0.6 to 1.6) in the Femto group, which was statistically significant (p = 0.003). Comparing the cylinder power there was a statistical difference between the two groups (p = 0.0015). Conclusions: This study shows that the method of flap creation has a significant impact on postoperative astigmatism with a significantly better postoperative UDVA in the Femto group. These findings suggest that the femtosecond laser provides a better platform for LASIK treatment of astigmatism than the commonly used microkeratome.

Décubitus ventral et syndrome de détresse respiratoire aiguë de l'adulte: de la théorie à la pratique [Prone position mechanical ventilation in the Acute Respiratory Distress syndrome: theoretical and practical considerations].

Mortality of the acute respiratory distress syndrome (ARDS) remains extremely high and only few evidence-based specific treatments are currently available. Protective mechanical ventilation has emerged as the comer stone of the management of ARDS to avoid the occurrence of ventilation-induced lung injuries (VILI). Mechanical ventilation in the prone position has often been considered as a rescue therapy reserved to refractory hypoxemia. Since the publication of the PROSEVA study in 2013, early prone positioning for mechanical ventilation should be recommended to improve survival of patients with severe ARDS. In this article, both the theoretical and practical aspects of mechanical ventilation in prone position are reviewed.

Basis set effects on the energy and hardness profiles of the hydrogen fluoride dimer

In earlier work, the present authors have shown that hardness profiles are less dependent on the level of calculation than energy profiles for potential energy surfaces (PESs) having pathological behaviors. At variance with energy profiles, hardness profiles always show the correct number of stationary points. This characteristic has been used to indicate the existence of spurious stationary points on the PESs. In the present work, we apply this methodology to the hydrogen fluoride dimer, a classical difficult case for the density functional theory methods