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This current concept, narrative review provides the latest integrated evidence of the musculoskeletal injuries involved with trail running and therapeutic strategies to prevent injury and promote safe participation. Running activities that comprise any form of off-road running (trail running, orienteering, short-long distance, different terrain, and climate) are relevant to this review. Literature searches were conducted to 1) identify types and mechanisms of acute and chronic/overuse musculoskeletal injuries in trail runners, 2) injury prevention techniques most relevant to running trails, 3) safe methods of participation and rehabilitation timelines in the sport. The majority of acute and chronic trail running-related musculoskeletal injuries in trail running occur in the lower leg, primarily in the knee and ankle. More than 70% are due to overuse, and ankle sprains are the most common acute injury. Key mechanisms underlying injury and injury progression include inadequate neuromotor control-balance-coordination, running through fatigue, and abnormal kinematics on variable terrain. Complete kinetic chain prehabilitation programs consisting of dynamic flexibility, neuromotor strength and balance, and plyometrics exercise can foster stable, controlled movement on trails. Patient education about early musculoskeletal pain symptoms and training adjustment can help prevent injury from progressing to serious overuse injuries. Real-time adjustments to cadence, step length, and knee flexion on the trail may also mitigate impact-related risk for injury. After injury occurs, rehabilitation will involve similar exercise components, but it will also incorporate rest and active rest based on the type of injury. Multicomponent prehabilitation can help prevent musculoskeletal injuries in trail runners through movement control and fatigue resistance.

Anti-gravity treadmill training is a therapeutic option to help recovering runners return to activity after injury. This current concept paper provides a synopsis of the latest evidence of the biomechanical and metabolic changes that occur with body weight support (BWS) treadmill training, effects of antigravity treadmill training on clinical outcomes and clinical case studies in injured runners. Literature searches identified studies with descriptive, experimental and interventional designs and case studies that examined acute and chronic use of antigravity treadmills in runners and relevant populations. Laboratory-based studies were included to provide technical considerations for rehabilitation programming. Antigravity treadmills use causes reductions in cadence, ground reaction forces (GRF), GRF impulses, knee and ankle range of motion, and vertical stiffness, with elevations in stride duration, flight time, ground contact time, and plantarflexion. Antigravity treadmills appear useful across a spectrum of injuries in runners, including postsurgical repair of osteochondral defect, stress reactions (medial tibia, pelvis), and lumbar disc herniation. Runners may preserve aerobic fitness, muscle activation patterns, and muscle mass during recovery compared to traditional rehabilitation protocols. Technical considerations for accurate loading include treadmill frame adjustment to appropriate height to ensure accuracy of level of BWS while running, and monitoring for fast cadence to ensure impact loading rates remain low. Speed or grade can be increased to maintain metabolic demand and fitness while minimizing bone and tissue loading. Monitoring for symptom provocation will guide protocol adjustments to BWS and prescriptions. Once able to run pain-free (sustained or interval) >95% BWS for >30 min, the runner is likely ready to safely transition to ground running. Antigravity treadmill training can be considered when available to facilitate smooth transition back to ground running in a conditioned state.

Background Juvenile Idiopathic Arthritis (JIA) is a chronic inflammatory arthritis that impacts biomechanical features of gait. This systematic review describes the effects of JIA on gait motion parameters and walking performance. Methods Six databases were searched (PubMed/Medline, Cochrane, the EBSCOHost database SPORTDiscus, Web of Science, and Embase). Studies were restricted to children with any subtype of JIA who were assessed for gait motion features (kinematic, kinetic, temporalspatial) or walking performance (velocity or distance covered); could include intervention or treatment exposure with measures of gait and gait speed; could involve comparison of gait in JIA to healthy controls. Quality of evidence was assessed using the GRADE system. This systematic review was registered at PROSPERO (CRD42018109582) Results The search yielded 625 papers, 23 of which described biomechanical features of gait and/or assessed walking performance. Twenty studies measured walking velocity and walking ability using simple field tests or laboratory methods. Eleven studies measured temporalspatial parameters such as cadence, step length, stride length, step width, single and double support time. Nine studies evaluated kinetic measurements including joint power, flexion and extension and joint moments. Nine studies evaluated kinematic parameters including range of motion, pelvic tilt, center of motion and trunk sway. Conclusions Key features of gait in children with JIA include slower gait velocity, shortened step length, decreased range of motion at the hip, knee and ankle with trend towards flexion, decreased joint power, anteriorly tilted pelvis and trunk with shifted center of motion. There is a potential to ameliorate JIA-related gait changes with exercise and/or pharmaceutical interventions.

Background Non-therapeutic interventions such as practicing good hand hygiene continue to be the mainstay of protection from SARS-CoV-2 and other emerging respiratory viruses. Methods We have evaluated a range of commercially available personal care products including soaps, handwash liquids and alcohol-based hand sanitizers for antiviral efficacy against a clinical isolate of SARS-CoV-2 using internationally accepted standardized protocols at user-relevant contact time-points and product dilutions. Results All the tested products resulted in 3 to 4 log reduction of SARS-CoV-2 titer. Conclusion Our data re-affirms recommendations by global public health authorities that proper hand hygiene can reduce SARS-CoV-2 viral load significantly which should likely limit spread of the contagion.

Background The study purpose was to determine whether 2-stage revision procedures result in superior outcomes and whether reverse shoulder arthroplasty produced superior outcomes to hemiarthroplasty or anatomic total shoulder arthroplasty at the time of reimplantation. Methods Our prospectively collected database was retrospectively reviewed for all surgically treated infected shoulder arthroplasties between 2006 and 2014. We included 47 patients in this study: 27 underwent a 2-stage revision, and 20 were treated with an antibiotic spacer as definitive treatment. Preoperative laboratory results, intraoperative cultures and pathology findings, recurrence of infection, complications, and outcome measures were compared between treatment groups. Results A recurrent infection developed in 3 patients in the antibiotic spacer group and 2 patients in the 2-stage revision group ( P = .25). A total of 20 procedure-related complications and 11 medical complications occurred between the 2 groups; however, there was no statistically significant difference between groups. The 2-stage group had statistically significantly better Constant scores (58.1 vs. 33.3, P = .04) and elevation (94.4° vs. 48.6°, P = .02) than the antibiotic spacer group. Subanalysis of the 2-stage revision group showed that reverse total shoulder arthroplasties had statistically superior Shoulder Pain and Disability Index, Simple Shoulder Test, American Shoulder and Elbow Surgeons, University of California at Los Angeles, and Constant scores; elevation; and abduction compared with hemiarthroplasties or anatomic total shoulder arthroplasties. Conclusion Two-stage revision procedures and use of an antibiotic spacer for definitive management of periprosthetic shoulder infections appear to be similar and effective in eradicating infections. Two-stage revisions using a reverse total shoulder arthroplasty at the time of reimplantation generate superior range of motion and functional outcome scores.

Distance runners can approach long descents with slow cadence and long steps, or a fast cadence with shorter steps. These approaches differentially affect mechanical loading and energy demand.This study determined the cadence range in which biomechanical loads, caloric unit cost and energy cost were simultaneously minimized during downhill running (DR).Trained runners (N = 40; 25.6 ± 7.2 yr; 42.5% female) participated in this experimental study. Participants ran on an instrumented treadmill while wearing a portable gas analyzer during six conditions: control normal level running (LR) at 0 deg inclination (CON-0); control DR -6 deg inclinaton (CON-6); DR at cadences +/-5% and +/-10% different from CON-6. A motion analysis system was used to capture running motion, and an instrumented treadmill captured force data. Cardiopulmonary measures, rating of perceived exertion (RPE), and biomechanical measures (temporal spatial parameters, peak ground reaction forces [GRF], vertical average loading rate [VALR], impulses) were calculated. Caloric unit cost and energy costs were standardized per unit distance.Running at -10% cadence increased HR by 10 bpm compared to CON-6 (p 0.0001). Vertical excursion of the center of mass and step length were greatest in the cadence -10% and least in the cadence +10% conditions (both p 0.0001). RPEs were higher among all cadence conditions compared to CON-0 (p 0.0001). Caloric unit costs were lowest in CON-6, and +/5% cadence conditions compared to the CON-0 and +/-10% conditions (-2.1% to -12.3%, respectively; p 0.05). Peak GRF and VALR were not different among conditions; vertical impulses were greatest in the -10% condition compared to CON-0, CON-6 and +5% and +10% by 11.3-14.5% (p .001).Changing cadence across level and downhill stretches is likely not necessary and may actually increase perceived effort of running. Running downhill at cadences that range +/-5% of preferred simultaneously minimize caloric unit cost and impulse loading.

For persons with osteoarthritis (OA), nutrition education may facilitate weight and OA symptom management.The primary aim of this study was to determine preferred OA-related nutritional and weight management topics and their preferred delivery modality. The secondary aim was to determine whether there is a disconnect between what patients want to know about nutrition and OA management and what information health-care professionals (HCPs) are providing to patients.The Osteoarthritis Action Alliance surveyed individuals with OA to identify their preferences, categorized in 4 domains:Survey responses from 338 individuals with OA and 104 HCPs were included. The highest preference rankings in each domain were:There is disparity between the nutrition education content preferred by individuals with OA (which often lacks empirical support) and evidence-based topics being discussed by HCPs. HCPs must communicate evidence-based management of joint health and OA symptoms in patient-preferred formats. This study explored the information gap between what individuals with OA want to know and what HCPs believe they need to know.

This study applies Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data and the Mixture Tuned Matched Filtering (MTMF) algorithm to map the sub-pixel distribution of alteration minerals associated with the Masahim volcano, SE Iran for understanding the spatial relationship between alteration minerals and volcano facies. Investigations of the alteration mineralogy were conducted using field-spectroscopy, X-ray diffraction (XRD) analysis and ASTER Short Wave Infrared (SWIR) spectral data. In order to spectrally characterize the stratovolcano deposits, lithological units and alteration minerals, the volcano was divided into three facies: the Central, Proximal, and Medial–distal facies. The reflectance spectra of rock samples show absorption features of a number of minerals including white mica, kaolinite, montmorillonite, illite, goethite, hematite, jarosite, opal, and chlorite. The end-members of key alteration minerals including sericite (phyllic zone), kaolinite (argillic zone) and chlorite (propylitic zone) were extracted from imagery using the Pixel Purity Index (PPI) method and were used to map alteration minerals. Accuracy assessment through field observations was used to verify the fraction maps. The results showed that most prominent altered rocks situated at the central facies of volcano. The alteration minerals were discriminated with the coefficient of determination (R2) of 0.74, 0.81, and 0.68 for kaolinite, sericite, and chlorite, respectively. The results of this study have the potential to refine the map of alteration zones in the Masahim volcano.

Advancing age and adiposity contribute to musculoskeletal degenerative diseases and the development of sarcopenic obesity. The etiology of muscle loss is multifactorial, and includes inflammation, oxidative stress and hormonal changes, and is worsened by activity avoidance due to fear of pain. The risk for mobility disability and functional impairment rises with severity of obesity in the older adult. Performance measures of walking distance, walking speed, chair rise, stair climb, body transfers and ability to navigate obstacles on a course are adversely affected in this population, and this reflects decline in daily physical functioning. Exercise training is an ideal intervention to counteract the effects of aging and obesity. The 18 randomized controlled trials of exercise studies with or without diet components reviewed here indicate that 3–18 month programs that included aerobic and strengthening exercise (2–3 days per week) with caloric restriction (typically 750 kcal deficit/day), induced the greatest change in functional performance measures compared with exercise or diet alone. Importantly, resistance exercise attenuates muscle mass loss with the interventions. These interventions can also combat factors that invoke sarcopenia, including inflammation, oxidative stress and insulin resistance. Therefore, regular multimodal exercise coupled with diet appears to be very effective for counteracting sarocpenic obesity and improving mobility and function in the older, obese adult.

Inadvertent transplantation of an α-1 antitrypsin-deficient liver into an adult man provided a unique opportunity to follow the natural history of morphological changes in serial liver biopsies. After doing well initially, the patient developed liver function test abnormalities 6 years posttransplant, but biopsies at that time and 2 years later revealed only chronic hepatitis with no specific features. It was only upon repeat biopsy 10 years posttransplant that characteristic cytoplasmic inclusions appeared. Genotypic and phenotypic testing of pretransplant and posttransplant specimens confirmed α-1 antitrypsin deficiency in the transplanted liver. Serologic tests for viral hepatitis and autoimmune disease were negative throughout the pretransplant and posttransplant period. The case suggests that patients with chronic hepatitis of unknown etiology should be tested for the possibility of α-1 antitrypsin deficiency and illustrates the prolonged course that may precede the development of typical cytoplasmic inclusions in the liver.

The Neyriz ophiolite occurs along the Zagros suture zone in SW Iran, and is part of a 3000-km obduction belt thrusting over the edge of the Arabian continent during the late Cretaceous. This complex typically consists of altered dunites and peridotites, layered and massive gabbros, sheeted dykes and pillow lavas, and a thick sequence of radiolarites. Reflectance and emittance spectra of Neyriz ophiolite rock samples were measured in the laboratory and their spectra were used as endmembers in a spectral feature fitting (SFF) algorithm. Laboratory spectral reflectance measurements of field samples showed that in the visible through shortwave infrared (VNIR–SWIR) wavelength region the ultramafic and gabbroic rocks are characterized by ferrous-iron and Fe, Mg OH spectral features, and the pillow lavas and radiolarites are characterized by spectral features of ferric-iron and Al OH. The laboratory spectral emittance spectra also revealed a wide wavelength range of Si O spectral features for the ophiolite rock units. After continuum removal of the spectra, the SFF classification method was applied to the VNIR + SWIR 9-band stack, and to the 11-band data set of SWIR and TIR data sets of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor, using field spectra as training sets for evaluating the potential of these data sets in discriminating ophiolite rock units. Output results were compared with the geological map of the area and field observations, and were assessed by the use of confusion matrices. The assessment showed, in terms of kappa coefficient, that the SFF classification method with continuum removal applied to the SWIR data achieved excellent results, which were distinctively better than those obtained using VNIR + SWIR data and TIR data alone.

The accumulation of heavy metals in the biosolid amended soils and the risk of their uptake into different plant parts is a topic of great concern. This study examines the accumulation of several heavy metals and nutrients in soybeans grown on biosolid applied soils and the use of remote sensing to monitor the metal uptake and plant stress. Field and greenhouse studies were conducted with soybeans grown on soils applied with biosolids at varying rates. The plant growth was monitored using Landsat TM imagery and handheld spectroradiometer in field and greenhouse studies, respectively. Soil and plant samples were collected and then analyzed for several elemental concentrations. The chemical concentrations in soils and roots increased significantly with increase in applied biosolid concentrations. Copper (Cu) and Molybdenum (Mo) accumulated significantly in the shoots of the metal-treated plants. Our spectral and Landsat TM image analysis revealed that the Normalized Difference Vegetative Index (NDVI) can be used to distinguish the metal stressed plants. The NDVI showed significant negative correlation with increase in soil Cu concentrations followed by other elements. This study suggests the use of remote sensing to monitor soybean stress patterns and thus indirectly assess soil chemical characteristics.

The objective of the study was to determine whether short-term antioxidant (AOX) supplementation affects insulin sensitivity, endothelial adhesion molecule levels, and oxidative stress in overweight young adults. A randomized, double-blind, controlled study tested the effects of AOXs on measures of insulin sensitivity (homeostasis model assessment [HOMA]) and quantitative insulin sensitivity check index), endothelial adhesion molecules (soluble intercellular adhesion molecule-1, vascular adhesion molecule, and endothelial-leukocyte adhesion molecule-1), adiponectin, and oxidative stress (lipid hydroperoxides) in overweight and normal-weight individuals (N = 48, 18-30 years). Participants received either AOX (vitamin E, 800 IU; vitamin C, 500 mg; beta-carotene, 10 mg) or placebo for 8 weeks. The HOMA values were initially higher in the overweight subjects and were lowered with AOX by week 8 (15% reduction, P = .02). Adiponectin increased in both AOX groups. Soluble intercellular adhesion molecule-1 and endothelial-leukocyte adhesion molecule-1 decreased in overweight AOX-treated groups by 6% and 13%, respectively (P < .05). Plasma lipid hydroperoxides were reduced by 0.31 and 0.70 nmol/mL in the normal-weight and overweight AOX-treated groups, respectively, by week 8 (P < .05). Antioxidant supplementation moderately lowers HOMA and endothelial adhesion molecule levels in overweight young adults. A potential mechanism to explain this finding is the reduction in oxidative stress by AOX. Long-term studies are needed to determine whether AOXs are effective in suppressing diabetes or vascular activation over time.

The objective of this study was to investigate the effects of different construction practices on the spectral characteristics of the concrete. Concrete blocks of identical shape and size (20 × 20 × 6 cm 3 ) were prepared using different treatment processes to establish eight different concrete characteristics. The different concrete treatments were: T C (control), T NC (no cure), T CL (cool cure), T H (heat cure), T HW (high water content), T HC (half cement), T G (gravel), and T L (limestone). Spectral reflectance of all the concrete blocks was obtained in the laboratory from 350–2500 nm spectral range using a portable, hand-held spectroradiometer. The spectral reflectance of the different concrete treatments varied systematically with changes in the concrete characteristics that resulted from different construction practices. Detailed spectral analysis shows that the spectral absorption features around 450, 1380 and 1850 nm are highly correlated with changes in the characteristics of the concrete. The spectral ratios R 600 /R 450 , R 1380 /R 1440, R 1850 /R 1950 and R 2150 /R 880 can clearly differentiate the T NC - and T CL -treated concrete blocks from the other blocks with different concrete treatments. The spectral ratio R 600 /R 450 can differentiate the T C -, T G - and T L -treatments, which were considered to have better concrete quality from the rest of the concrete treatments. The spectral results clearly indicate the potential application of spectral reflectance in assessing concrete characteristics after the concrete has hardened.

The objective of this study was to measure the in situ spectral reflectance of lake water that contains a bloom of Microcystis, a species of cyanobacteria. Reflectance spectra (350–2,500 nm) of lake water near a boat dock in Upper Klamath Lake, Oregon, were collected with a portable spectrora-diometer on a cloud-free day with sunlight as a source of illumination between 0845 to 0915 hours, Pacific Daylight Time (PDT) on 17 August 2004, at a near-normal angle of observation. The averaged spectrum of the lake water containing the Microcystis bloom exhibits reflectance maxima from 550–590 nm and near 710 nm wavelengths and reflectance minima near 630 nm and 675 nm wavelengths. The reflectance gradually decreases from 810–1,000 nm and has very low reflectance in the 1,000–2,500 nm wavelength region. Our results show that the spectral reflectance of Microcystis at this stage of its bloom remains low for wavelengths longer than 1,000 nm in the near-infrared region of the spectrum. These spectral result...

To compare the outcomes of patients who have gone to inpatient rehabilitation after primary total hip arthroplasty (THA) and revision THA.Retrospective, comparative study.Fifty-bed freestanding, university-affiliated rehabilitation hospital.Two hundred fifty-five male and female primary THA patients and 147 male and female revision THA patients.Interdisciplinary inpatient rehabilitation.Length of stay (LOS), FIM instrument score and FIM motor score components, hospital charges, and discharge disposition location.FIM scores improved from admission to discharge by 29.7 and 27.9 points for the primary THA and revision THA groups, respectively (P.05). LOS was shorter for primary THA patients compared with revision THA patients (10.0d vs 11.5d, P.05). FIM efficiency (DeltaFIM/LOS) was greater for primary THA compared with revision THA (3.4 and 2.7 points/day, P.05). Total rehabilitation hospital charges were 11,421 US dollars and 13,707 US dollars for the primary and revision THA groups, respectively, with the mechanical and infection revision THAs incurring the greatest charges (14,596 US dollars and 15,386 US dollars, respectively; P.001). Compared with primary THA, revision THA patients were twice as likely to be discharged to locations other than home.FIM score improvement was lower and LOS and hospital charges were greater in revision THA than in primary THA after rehabilitation. Infection revision THA patients gained less functional independence and were discharged home less often than mechanical or pain revision THA patients; finally, infection and mechanical revision THA accrued the highest hospital charges.

To retrospectively examine the effects of sex and age on the inpatient rehabilitation outcomes of patients after total hip arthroplasty (THA).Exploratory, retrospective study.A university-affiliated rehabilitation hospital.Male and female THA patients (N=332) were stratified into age brackets (65y, 65-84y,or=85y). All patients completed interdisciplinary inpatient rehabilitation.Not applicable.Length of stay (LOS), FIM instrument scores, FIM efficiency (FIM/LOS), hospital costs, and discharge disposition location were collected by chart review.Regardless of age, women had lower FIM scores at admission and discharge than men (P.05). FIM efficiency was 22% to 53% lower for women in primary THA and 16% to 85% lower in revision THA than men (P=.001). Women accrued higher total hospital charges than men (13,099 dollars vs 11,141 dollars; P.05), and were discharged home less frequently than men (84.4% vs 90.9%; P.05). Admission FIM scores were 10.6% and 8.9% lower and discharge FIM scores were 7.3% and 9.2% lower in patients 85 years or older than those less than 65 or 65 to 84 years (P.01). FIM efficiency was 25% to 38% higher in patients less than 85 years than those 85 years and older (P=.015), and 37% higher in men than women (P=.001). Patients 85 years and older were discharged less frequently to home than patients less than 85 years (P.05).All patients made functional improvement after inpatient rehabilitation, but women and patients 85 years and older had longer LOS and lower FIM efficiency, incurred greater hospital charges, and were less likely to be discharged to home than men and younger counterparts.

To measure lumbar extensor strength in overweight (OVW) and nonoverweight (NOVW) elderly adults before and after resistance exercise training (RX).Descriptive, comparative study.University-based wellness center and research facility.Eighty-four adults (age range, 60-83 y) were placed into 1 of 2 groups based on body mass index (BMI): control (NOVW; mean BMI, 22.5 kg/m(2)) or OVW (mean BMI, 29.2 kg/m(2)). Subjects were then randomly assigned to either a resistance exercise (RX) or nonexercising group.Six months of total body RX and isolated lumbar extension exercise.Body composition, isometric lumbar extension strength, and 1-repetition maximum for each of the training exercises.Upper-body strength increased by 18.3% and 17.2% for the NOVW-RX and OVW-RX groups, respectively. Lower-body strength increased by 12.7% and 19.5% for the NOVW-RX and OVW-RX groups, respectively. At baseline, the OVW participants had greater total lumbar extension strength (1067 Nm vs 714 Nm) compared with the NOVW participants (P.05). When expressed per kilogram of fat-free mass, there were no differences in baseline total lumbar extension strength. After RX, lumbar extension strength increased by 58% and 34% for the NOVW-RX and OVW-RX groups, respectively (P.05). No changes in lumbar extension, upper- or lower-body strength were noted for the nontraining groups.OVW subjects were found to have greater absolute and similar relative, upper-body, lower-body, and lumbar extension strength at baseline when compared with their NOVW counterparts. Also, isolated lumbar extension exercise was effective in improving lumbar extensor strength in OVW and NOVW persons.

Communications and imaging experiments conducted in the Arizona desert during July of 2002 with the National Aeronautics and Space Administration (NASA) and the United States Geological Survey (USGS) helped to identify a fundamental suite of scientific instruments focused on surface composition and temperature determination for the calibration and validation of NASA and USGS spaceborne and airborne sensors and to integrate them with a hybrid mobile wireless and satellite network for lunar and planetary exploration and emergency response. The 2002 experiment focused on the exchange of remotely sensed and ground truth geographic information between analysts and field scientists. That experiment revealed several modifications that would enhance the performance and effectiveness of geographic information networks (GIN) for lunar and planetary exploration and emergency response. Phase 2 experiments conducted during June 2003 at the USGS Earth Resources and Observation Systems (EROS) Data Center's geologic imaging test site near Dinosaur National Monument in the NE Utah desert incorporated several of the lessons learned from the 2002 experiment and successfully added five major new components: (1) near-real-time hyperspectral and multispectral satellite image acquisition, (2) remotely controlled and coordinated mobile real-time ground sensor measurements during the imaging satellite overpass, (3) long-delay optimized Transmission Control Protocol/Internet Protocol TCP/IP protocols to improve network performance over geosynchronous communications satellite circuits, (4) distributed, multinode parallel computing on NASA's Internet Power GRID (IPG), and (5) near-real-time validation of satellite imagery as part of a successful test of the NASA-USGS National Emergency Mapping Information System.

The Boeing Landing Suitability Index (BLSI) is a computer algorithm designed at Bowling Green State University for The Boeing Company for the purpose of mapping candidate aircraft operating sites of different “runway” lengths in natural terrain from LANDSAT TM data. Four LANDSAT TM frames (each 115 miles × 115 miles in area) from parts of California, New Mexico, South Dakota, and Louisiana (with annual rainfalls averaging approximately 3.5, 7, 17, and 53 in., respectively, though the Louisiana frame was collected during a drought year that had 28 in. of annual rainfall) were entered as inputs to the BLSI algorithm, which identified pixels in each of the frames that were sufficiently flat, treeless, and absent of surface water to land an aircraft on them, present weather conditions permitting, and perform off-loading, on-loading, and take-off operations. Adjustments were made to the algorithm for differences in annual rainfall. Although no attempt was made before these field trips to force BLSI to map surface firmness, the California Bearing Ratio (CBR) was measured in the field on-site and off-site with dynamic cone penetrometers by a contractor for the Air Force Research Lab (Tyndall AFB in Florida) for several of these candidate aircraft operating sites. We found that all of the sites selected by BLSI that were visited in the field were suitably flat for landing and had no surface water or trees on them (except for one small tree that was younger than the LANDSAT frame employed for that region). Fortunately, most of these candidate aircraft operating sites found by BLSI had firmer ground than their immediate surroundings, as measured from the dynamic cone penetrometers. Our field observations support the hypothesis that BLSI is primarily mapping very subtle, local topographic highs. Such a subtle topographic high, which may rise only few feet from the middle to the edge of a candidate aircraft operating site, usually has a hard pan beneath it, owing to its relatively better drainage, compared with its immediate surrounds. This may account for its greater firmness, compared to its surrounds. Because the slopes are so small and the feature is slightly convex upward, there are no gullies on candidate aircraft operating sites. This causes the subtle topographic highs to be very flat and without rocks, unlike higher-sloped regions, where water in gullies tend to wash rocks. This seems the most reasonable explanation for why a pixel size as gross as 28.5 m (LANDSAT TM bands 1–5 and 7) is adequate to map such features. BLSI displayed as a continuous-toned image has potential for mapping areas of highest trafficability for wheeled vehicles, with lower BLSI values (shown as purple or blue areas) having the greatest trafficability.

Algorithms were developed from LANDSAT 7 ETM+ data for the July 1, 2000 overpass and LANDSAT 5 Thematic Mapper (TM) data for the September 27, 2000 overpass for Path 20 Row 31 (including Toledo, OH) to measure relative phycocyanin content (PC) and turbidity in the western basin of Lake Erie. Water samples were collected from discrete hydrographic stations arranged in a 20×4 km grid adjacent to the Ohio shoreline during a 6-h period spanning each of the two LANDSAT overpasses. The samples were analyzed for chlorophyll (chl) a content and turbidity. In addition, the concentration of phycocyanin, a light-harvesting pigment associated with cyanobacteria, was estimated from the ratio of phycocyanin/chl a in vivo fluorescence (IVPF/IVCF). A dark-object-subtracted, spectral ratio model derived from the July 1, 2000 data was found to be the most robust, when applied to the September 27, 2000 data. The same July 1, 2000 model (or algorithm) for PC was then applied to LANDSAT 7 ETM+ frames for July 16 and August 1, 2002 of the Path 19 Row 31 frame (including Cleveland, OH) and to the August 8, 2002 frame of Path 20 Row 31. Moderate, very low, and high PC values were detected in the western basin of Lake Erie on July 16, August, 1, and August 8, 2002, respectively. On September 17, 2002, local media reported a large Microcystis bloom in the western basin. The high PC values on August 8, 2002 may have represented early stage detection of the large Microcystis bloom that was reported 5 weeks later. The PC algorithm derived in this study will improve our understanding of the temporal and spatial dynamics of cyanobacterial bloom formation in Lake Erie and other systems. It may also serve to alert municipalities to the presence of potentially toxic bloom events.

We have calculated the optical absorption matrix elements for a spherical silicon quantum dot embedded in silicon dioxide with the addition of a parabolic potential which is used to tune the bound state energy levels. The photon absorption from the ground state to the excited states was calculated as a function of the parabolic potential curvature constant and the dot radius which varied between 2 and 6 nm . The results show that we can tune the wavelength in the entire visible range. Furthermore, the absorption cross section was found to change by several orders of magnitude with increasing parabolic potential curvature constant. For large parabolic curvature constant the transition move out of the visible range, and the number of allowed transition increased with the dot radius.

Poster 28 Predictors of Readmission to Acute Care and Mortality in the Inpatient Rehabilitation Setting Among Cardiovascular Patients. Heather K. Vincent, PhD, MS (University of Florida, Gainesville, FL); Sally Gamon, RN; Kevin R. Vincent, MD, PhD. Disclosure: H.K. Vincent, ARA Research Institute, AMRPA; S. Gamon, None; K.R. Vincent, None. Objective: To identify factors associated with readmission to acute care and mortality in the inpatient rehabilitation facility (IRF). Design: Retrospective study. Setting: A free-standing university-affiliated IRF. Participants: Cardiovascular patients who received acute care and subsequent inpatient rehabilitation (N 138; 64.1% men; age, 72.4 11.8y; 80.8% Medicare insured) from December 1, 2002, to March 31, 2006. Diagnoses included coronary artery disease, heart failure, peripheral vascular disease, aneurysms, acute myocardial infarction (MI), heart valve repair or replacement, heart transplant, and peripheral bypass graft. Interventions: Not applicable. Main Outcome Measures: Patient variables (interventions, diagnostic test results, care needs, FIM instrument scores), discharge disposition, readmissions to acute care, and mortality. Results: 15.4% of patients were readmitted to acute care for MI symptoms, failure to thrive, falls, mental status change, and infection. 2.4% of patients expired during rehabilitative care; causes of death included second infarctions, heart failure exacerbation, and blood loss. Patients readmitted to acute care had a longer IRF length of stay (LOS) than remaining patients (23.2 5.1d vs 13.8 7.8d, respectively; P .05) but total IRF charges did not differ statistically ($23,550 vs $19,567, P .279). Ageand sexadjusted regression models revealed that independent predictors of readmission to acute care included presence of dysrhythmias or foot ulcers, an indwelling catheter, angina, peripheral vascular disease, anxiety, lung atelectasis, development of infections, percentage of days active with therapies, and IRF LOS (all models, P .05). Independent predictors of mortality in the IRF included previous infarction prior to rehabilitation, angina, presence of diabetes, and specific admission low FIM subscores (bathing, verbal expression, problem solving, memory, auditory comprehension) (all P .05). Conclusions: Prediction of acute care readmission and mortality is multifaceted, and these preliminary findings can be used to start identifying which patients are less likely to succeed in the IRF.