Clinical Importance of Transthoracic Echocardiography with Direct Input from Treating Physicians.

BACKGROUND: The recent report that appropriately performed echocardiographic examinations result in active changes in management in only one third of patients has challenged the validity of current appropriate use criteria. Limited information exists about the clinical importance of transthoracic echocardiography (TTE) to guide management and rule out important alternative pathology. METHODS: The clinical impact of inpatient TTE performed at the Mayo Clinic over a 20-week period between October 14, 2013, and March 3, 2014, was investigated. Studies were included if they were ordered within 72 hours of admission, and treating physicians participated in a real-time survey regarding the clinical importance of TTE. Appropriate use was determined by two independent investigators, with differences adjudicated by a third investigator. Clinical impact was derived from physicians' survey responses and independently confirmed by chart review. RESULTS: Of the 539 transthoracic echocardiographic examinations included in this study, 512 (95%) were appropriate, 16 (3%) may be appropriate and 11 (2%) rarely appropriate. Although only 48% of participating physicians actively changed management on the basis of findings on TTE, 97% responded that TTE answered their clinical questions, and 95% would still order TTE in similar clinical contexts. CONCLUSIONS: Most early inpatient transthoracic echocardiographic studies at our institution were appropriate and answered specific clinical questions important for management decisions in the opinion of the treating physician. Confirming a plan of care already in place and ruling out alternative pathology may be as important clinically as uncovering new findings or changing management.

Feasibility of Using Low-Cost Motion Capture for Automated Screening of Shoulder Motion Limitation after Breast Cancer Surgery.

OBJECTIVE: To determine if a low-cost, automated motion analysis system using Microsoft Kinect could accurately measure shoulder motion and detect motion impairments in women following breast cancer surgery. DESIGN: Descriptive study of motion measured via 2 methods. SETTING: Academic cancer center oncology clinic. PARTICIPANTS: 20 women (mean age = 60 yrs) were assessed for active and passive shoulder motions during a routine post-operative clinic visit (mean = 18 days after surgery) following mastectomy (n = 4) or lumpectomy (n = 16) for breast cancer. INTERVENTIONS: Participants performed 3 repetitions of active and passive shoulder motions on the side of the breast surgery. Arm motion was recorded using motion capture by Kinect for Windows sensor and on video. Goniometric values were determined from video recordings, while motion capture data were transformed to joint angles using 2 methods (body angle and projection angle). MAIN OUTCOME MEASURE: Correlation of motion capture with goniometry and detection of motion limitation. RESULTS: Active shoulder motion measured with low-cost motion capture agreed well with goniometry (r = 0.70-0.80), while passive shoulder motion measurements did not correlate well. Using motion capture, it was possible to reliably identify participants whose range of shoulder motion was reduced by 40% or more. CONCLUSIONS: Low-cost, automated motion analysis may be acceptable to screen for moderate to severe motion impairments in active shoulder motion. Automatic detection of motion limitation may allow quick screening to be performed in an oncologist's office and trigger timely referrals for rehabilitation.

Observation of hole accumulation in Ge/Si core/shell nanowires using off-axis electron holography.

Hole accumulation in Ge/Si core/shell nanowires (NWs) has been observed and quantified using off-axis electron holography and other electron microscopy techniques. The epitaxial [110]-oriented Ge/Si core/shell NWs were grown on Si (111) substrates by chemical vapor deposition through the vapor-liquid-solid growth mechanism. High-angle annular-dark-field scanning transmission electron microscopy images and off-axis electron holograms were obtained from specific NWs. The excess phase shifts measured by electron holography across the NWs indicated the presence of holes inside the Ge cores. Calculations based on a simplified coaxial cylindrical model gave hole densities of (0.4 ± 0.2) /nm(3) in the core regions.

Spreading of liquid AuSi on vapor-liquid-solid-grown Si nanowires.

Vapor-liquid-solid growth of high-quality Si nanowires relies on the stability of the liquid metal seed. In situ transmission electron microscopy shows that liquid AuSi seed spreads along the sidewalls of Si nanowires for some growth conditions. This liquid thin film phase separates to form solid Au clusters as the nanowire is quenched below the solidus temperature. The length that the liquid film spreads from the seed and its thickness can be explained by considering the spreading thermodynamics of droplets on cylinders.

Kinetically induced kinking of vapor-liquid-solid grown epitaxial si nanowires.

Epitaxial Si nanowires grown from Au seeds using the vapor-liquid-solid method begin growing normal to the Si(111) substrate atop a tapered base. After a kinetically determined length, the NWs may kink away from [111] to another crystallographic direction. The smallest NWs prefer growth along 110 while larger Si NWs choose either 111 or 112 based on whether growth conditions favor Au-free sidewalls. "Vertical" growth normal to the Si(111) substrate is obtained only for slowly growing NWs with Au-decorated sidewalls. At the fastest growth rates, single-crystal Si NWs smoothly, continuously, and randomly vary their growth directions, producing a morphology that is qualitatively different than highly kinked growth.