The role of the stratospheric polar vortex for the austral jet response to greenhouse gas forcing

Future shifts of the austral midlatitude jet are subject to large uncertainties in climate model projections. Here we show that, in addition to other previously identified sources of inter-model uncertainty, changes in the timing of the stratospheric polar vortex breakdown modulate the austral jet response to greenhouse gas forcing during summertime (December-February). The relationship is such that a larger delay in vortex breakdown favors a more poleward jet shift, with an estimated 0.7-0.8-degree increase in jet shift per 10 days delay in vortex breakdown. The causality of the link between the timing of the vortex breakdown and the tropospheric jet response is demonstrated through climate modeling experiments with imposed changes in the seasonality of the stratospheric polar vortex. The vortex response is estimated to account for about 30% of the inter-model variance in the shift of the summertime austral jet, and about 45% of the mean jet shift

Post-Operative Rehabilitation for Scapular Muscle Reattachment: A Case Report

Background and Purpose: Scapular muscle detachment is a rare orthopedic problem that has been described in the literature in patients following traumatic events involving traction, direct trauma, or a motor vehicle accident. The purpose of this case report is to describe the post-operative rehabilitation following scapular muscle reattachment surgery. Unique to this case report is the patient\u27s perspective, an orthopedic physical therapist with 25 years of experience. Case Description: A 47-year-old female physical therapist experienced a traction injury to bilateral upper extremities during a medical procedure resulting in bilateral rhomboid, and bilateral lower trapezius muscles were detached from the medial scapular border. Reconstruction of the left scapulothoracic musculature occurred five and one-half years post-injury with the right repaired one year later. This case report describes the rehabilitation program that took one-year to recover for each arm with a period of protected motion for 16-weeks and gradual return to function as a manual physical therapist over a period of one-year. Outcomes: The American Shoulder and Elbow Surgeons (ASES) Standardized Assessment Form and pain-free range of motion was used pre- and postoperatively. Left and right shoulder pre-operative ASES scores were 68 and 72, respectively. At the one-year post-operative the left shoulder was rated at 82 and the right shoulder was 90. Pain-free range of motion was achieved in both arms by one year. Functional limitations requiring strength overhead were the slowest to return and were not completely back at one year following either surgery. Discussion: Rehabilitation protocols for scapular muscle reattachment surgery are not commonly available to allow physical therapists to guide their patients and structure a rehabilitation program. This case report provides a sample pre-operative set of educational guidelines and a post-operative protocol for use after scapular reattachment surgery. This case report is unique because it offers a patient perspective who is a physical therapist and underwent this surgery twice. Therefore, providing insight on how to prepare for such a unique operation. The slow recovery is due to three issues 1) the prolonged time from injury to diagnosis created significant muscle wasting and muscular imbalance of surrounding tissues, 2) once this tissue was repaired it requires months of protection to recover, 3) the involved scapulothoracic muscle have to regain adequate strength as the foundation for upper extremity functions. Level of evidence: Level 5

Simulator study of stall/post-stall characteristics of a fighter airplane with relaxed longitudinal static stability

A real-time piloted simulation was conducted to evaluate the high-angle-of-attack characteristics of a fighter configuration based on wind-tunnel testing of the F-16, with particular emphasis on the effects of various levels of relaxed longitudinal static stability. The aerodynamic data used in the simulation was conducted on the Langley differential maneuvering simulator, and the evaluation involved representative low-speed combat maneuvering. Results of the investigation show that the airplane with the basic control system was resistant to the classical yaw departure; however, it was susceptible to pitch departures induced by inertia coupling during rapid, large-amplitude rolls at low airspeed. The airplane also exhibited a deep-stall trim which could be flown into and from which it was difficult to recover. Control-system modifications were developed which greatly decreased the airplane susceptibility to the inertia-coupling departure and which provided a reliable means for recovering from the deep stall

Sum Rules for Multi-Photon Spectroscopy of Ions in Finite Symmetry

Models describing one- and two-photon transitions for ions in crystalline environments are unified and extended to the case of parity-allowed and parity- forbidden p-photon transitions. The number of independent parameters for characterizing the polarization dependence is shown to depend on an ensemble of properties and rules which combine symmetry considerations and physical models.Comment: 16 pages, Tex fil

Do Scapular Kinematics Alter during the Performance of the Scapular Assistance Test and Scapular Retraction Test: A Pilot Study

Objective: To describe to what degree and in what plane biomechanical alterations occur during the performance of the Scapular Retraction test (SRT) and Scapular Assistance Test (SAT). Design: Laboratory Pilot Study Participants: Eight symptomatic and 7 asymptomatic subjects were instrumented with electromagnetic sensors. Main Outcome Measures: The SRT and SAT were performed with the scapula stabilized and unstabilized. The scapular kinematic variables of posterior tilt, internal rotation, upward rotation, protraction, and elevation were measured during both tests. Results: Descriptive analysis of scapular kinematics suggested that posterior tilt was primarily increased during both clinical tests in both groups. Both groups decreased in scapular elevation, indicating that the scapula was being depressed during the SRT. There was no meaningful change in force during the SRT. Conclusion: These findings indicate that both the SRT and SAT appear to alter scapular motion in both groups. The interpretations of these results are limited due to the small sample size and large confidence intervals, but suggest that these tests change specific positions of the scapula. Further research into these tests is needed to confirm these biomechanical alterations, and to determine the value of these tests when developing rehabilitation protocols in patients with shoulder pain

Level of Patient-Physician Agreement in Assessment of Change Following Conservative Rehabilitation for Shoulder Pain

Background Assessment of health-related status has been shown to vary between patients and physicians, although the degree of patient–physician discordance in the assessment of the change in status is unknown. Methods Ninety-nine patients with shoulder dysfunction underwent a standardized physician examination and completed several self-reported questionnaires. All patients were prescribed the same physical therapy intervention. Six weeks later, the patients returned to the physician, when self-report questionnaires were re-assessed and the Global Rating of Change (GROC) was completed by the patient. The physician completed the GROC retrospectively. To determine agreement between patient and physician, intra-class correlation (ICC) coefficient and Pearson’s r using the 15-point GROC and weighted kappa using a consolidated three-point GROC were calculated. Results Utilizing the 15-point GROC, complete agreement was observed in 37 of 99 patients (37%). ICC and Pearson’s r between patient and physician were 0.62 and 0.63, respectively. Utilizing a consolidated three-point GROC, complete agreement was observed in 76 of 99 patients (77%). Weighted kappa was 0.62. Conclusions Assessment of change reported by the patient demonstrates moderate to good agreement with physician assessment. These findings indicate that the GROC does reflect and represent similar assessment of change in health status by patients and physicians. This can aid discussion of both past treatment results and future treatment plans

Air Traffic Management Technology Demostration: 1 Research and Procedural Testing of Routes

NASA's Air Traffic Management Technology Demonstration-1 (ATD-1) will operationally demonstrate the feasibility of efficient arrival operations combining ground-based and airborne NASA technologies. The ATD-1 integrated system consists of the Traffic Management Advisor with Terminal Metering which generates precise time-based schedules to the runway and merge points; Controller Managed Spacing decision support tools which provide controllers with speed advisories and other information needed to meet the schedule; and Flight deck-based Interval Management avionics and procedures which allow flight crews to adjust their speed to achieve precise relative spacing. Initial studies identified air-ground challenges related to the integration of these three scheduling and spacing technologies, and NASA's airborne spacing algorithm was modified to address some of these challenges. The Research and Procedural Testing of Routes human-in-the-loop experiment was then conducted to assess the performance of the new spacing algorithm. The results of this experiment indicate that the algorithm performed as designed, and the pilot participants found the airborne spacing concept, air-ground procedures, and crew interface to be acceptable. However, the researchers concluded that the data revealed issues with the frequency of speed changes and speed reversals

Coulomb-oscillator duality in spaces of constant curvature

In this paper we construct generalizations to spheres of the well known Levi-Civita, Kustaanheimo-Steifel and Hurwitz regularizing transformations in Euclidean spaces of dimensions 2, 3 and 5. The corresponding classical and quantum mechanical analogues of the Kepler-Coulomb problem on these spheres are discussed.Comment: 33 pages, LaTeX fil

Air Traffic Management Technology Demostration Phase 1 (ATD) Interval Management for Near-Term Operations Validation of Acceptability (IM-NOVA) Experiment

The Interval Management for Near-term Operations Validation of Acceptability (IM-NOVA) experiment was conducted at the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) in support of the NASA Airspace Systems Program's Air Traffic Management Technology Demonstration-1 (ATD-1). ATD-1 is intended to showcase an integrated set of technologies that provide an efficient arrival solution for managing aircraft using Next Generation Air Transportation System (NextGen) surveillance, navigation, procedures, and automation for both airborne and ground-based systems. The goal of the IMNOVA experiment was to assess if procedures outlined by the ATD-1 Concept of Operations were acceptable to and feasible for use by flight crews in a voice communications environment when used with a minimum set of Flight Deck-based Interval Management (FIM) equipment and a prototype crew interface. To investigate an integrated arrival solution using ground-based air traffic control tools and aircraft Automatic Dependent Surveillance-Broadcast (ADS-B) tools, the LaRC FIM system and the Traffic Management Advisor with Terminal Metering and Controller Managed Spacing tools developed at the NASA Ames Research Center (ARC) were integrated into LaRC's Air Traffic Operations Laboratory (ATOL). Data were collected from 10 crews of current 757/767 pilots asked to fly a high-fidelity, fixed-based simulator during scenarios conducted within an airspace environment modeled on the Dallas-Fort Worth (DFW) Terminal Radar Approach Control area. The aircraft simulator was equipped with the Airborne Spacing for Terminal Area Routes (ASTAR) algorithm and a FIM crew interface consisting of electronic flight bags and ADS-B guidance displays. Researchers used "pseudo-pilot" stations to control 24 simulated aircraft that provided multiple air traffic flows into the DFW International Airport, and recently retired DFW air traffic controllers served as confederate Center, Feeder, Final, and Tower controllers. Analyses of qualitative data revealed that the procedures used by flight crews to receive and execute interval management (IM) clearances in a voice communications environment were logical, easy to follow, did not contain any missing or extraneous steps, and required the use of an acceptable workload level. The majority of the pilot participants found the IM concept, in addition to the proposed FIM crew procedures, to be acceptable and indicated that the ATD-1 procedures could be successfully executed in a nearterm NextGen environment. Analyses of quantitative data revealed that the proposed procedures were feasible for use by flight crews in a voice communications environment. The delivery accuracy at the achieve-by point was within +/-5 sec, and the delivery precision was less than 5 sec. Furthermore, FIM speed commands occurred at a rate of less than one per minute, and pilots found the frequency of the speed commands to be acceptable at all times throughout the experiment scenarios

Reliability of an Observational Method Used to Assess Tennis Serve Mechanics in a Group of Novice Raters

Background: Previous research has developed an observational tennis serve analysis (OTSA) tool to assess serve mechanics. The OTSA has displayed substantial agreement between the two health care professionals that developed the tool; however, it is currently unknown if the OTSA is reliable when administered by novice users. Purpose: The purpose of this investigation was to determine if reliability for the OTSA could be established in novice users via an interactive classroom training session. Methods: Eight observers underwent a classroom instructional training protocol highlighting the OTSA. Following training, observers participated in two different rating sessions approximately a week apart. Each observer independently viewed 16 non-professional tennis players performing a first serve. All observers were asked to rate the tennis serve using the OTSA. Both intra and inter-observer reliability were determined using Kappa coefficients. Results: Kappa coefficients for intra and inter-observer agreement ranged from 0.09 to 0.83 depending on the body position. A majority of all body positions yeilded moderate agreement and higher. Conclusion: This study suggests that the majority of components associated with the OTSA are reliable and can be taught to novice users via a classroom training session