Calcific Myonecrosis of the Upper Extremity: Case Report Rynders, Sara D; Boachie-Adjei, Yaw D., MD; Gaskin, Cree M., MD ...
The Journal of hand surgery (American ed.),
2012, 2012-Jan, 2012-1-00, 20120101, Letnik:
37, Številka:
1
Journal Article
Recenzirano
Calcific myonecrosis is an uncommon late sequela of limb trauma that results in calcification and necrosis of damaged muscle. It almost exclusively occurs in the lower extremity. We present a second ...case of calcific myonecrosis in the upper extremity.
The incidence, indications, and outcomes of coronary angiography (CAG) performed within 30 days following coronary artery bypass graft surgery (CABG) have received limited study.
We reviewed patients ...who underwent CAG within 30 days following CABG between April 2018 and September 2021 at a large quaternary healthcare system.
Of 2209 patients who underwent CABG during the study, 111 (5%) underwent CAG within 30 days following CABG. Mean age was 65 ± 10 years and they had high prevalence of comorbidities. Graft utilization was as follows: left internal mammary artery (LIMA) (84%); saphenous vein graft(s) (SVG) (81%); and right internal mammary artery (RIMA) (22%). The most common presentations/indications for angiography were cardiogenic shock (41%), ST-segment-elevation myocardial infarction (32%), and achieving complete revascularization by percutaneous coronary intervention (PCI) (16%). The LIMA, RIMA, and SVGs were completely/partially occluded in 41 (44%), 10 (42%), and 11 (50%) of patients, respectively. Of the 111 patients who underwent CAG, 55 (50%) underwent PCI, including 47 (85%) to the native vessel and 8 (15%) to the bypass graft, and 19 (17%) underwent repeat sternotomy. Overall, 29 patients (26%) required 30-day readmission following CAG and 19 (17%) died.
The incidence of CAG within 30 days following CABG is approximately 5%. Patients who need CAG following CABG have high complication rates (26% readmission and 17% mortality, respectively, at 30 days).
We examined the effects of a proprietary herbal/botanical supplement (StemSport, Stemtech, San Clemente, CA.) suggested to increase circulating stem cells, decrease inflammation, and attenuate ...exercise induced muscle damage on recovery from delayed onset muscle soreness (DOMS).
Sixteen subjects (male = 7, female = 9; age 23.8 ± 10 years; height 171.9 ± 10 cm, mass 72.2 ± 15 kg) were randomized in a crossover, double-blind, placebo controlled trial to receive a placebo or StemSport supplement (6150 mg/day) for 14 days. DOMS was induced on day 7 for both placebo and active conditions in the non-dominant elbow flexor group with repeated eccentric repetitions. Muscle swelling (biceps girth), elbow flexor isometric strength (hand held dynamometer), muscle pain/tenderness (visual analog scale), range of motion (active elbow flexion and extension), and inflammation (hsCRP, IL6, and TNF-α) were measured at baseline and at 24 h, 48 h, 72 h, and 168 h (1 week) post eccentric exercise. The crossover washout period was ≥14 days.
No significant condition-by-time interactions between placebo and StemSport supplementation were observed with regard to measures of pain (p = 0.59), tenderness (p = 0.71), isometric strength (p = 0.32), elbow flexion (p = 0.45), muscle swelling (p = 0.90), or inflammation (p > 0.90). Decrements in elbow extension range of motion 48 h post-exercise were less after StemSport supplementation (Δ elbow extension 48 h post; StemSport, -2.0 deg; placebo, -10 deg; p = 0.003).
These data suggest that compared to placebo, StemSport supplementation does not improve outcome measures related to muscle recovery after acute upper-arm induced DOMS.
The important task of tracking seismic activity requires both sensitive detection and accurate earthquake location. Approximate earthquake locations can be estimated promptly and automatically; ...however, accurate locations depend on precise seismic phase picking, which is a laborious and time‐consuming task. We adapted a deep neural network (DNN) phase picker trained on local seismic data to mesoscale hydraulic fracturing experiments. We designed a novel workflow, transfer learning‐aided double‐difference tomography, to overcome the 3 orders of magnitude difference in both spatial and temporal scales between our data and data used to train the original DNN. Only 3,500 seismograms (0.45% of the original DNN data) were needed to retrain the original DNN model successfully. The phase picks obtained with transfer‐learned model are at least as accurate as the analyst's and lead to improved event locations. Moreover, the effort required for picking once the DNN is trained is a small fraction of the analyst's.
Plain Language Summary
Seismic sensors are widely used to monitor many energy‐related systems. To monitor these systems effectively, we need to process a very large amount of data, which is very labor intensive. A few deep learning models have been developed to perform these tasks for earthquake‐generated signals. We adopted one of these deep learning models developed for kilometer scale and updated it for signals recorded from a meter‐scale project. This process not only allows us to overcome the significant spatial and temporal scale difference between our data and the data used by the original deep learning model but also significantly reduces the amount of required training data. Our results show that the updated model matches human performance but with a much faster speed. A workflow that combines the deep learning algorithm with existing imaging technologies enables improvements for both monitoring small earthquakes and studying subsurface structure.
Key Points
We successfully applied transfer learning to a neural network for data with orders of difference in spatial and temporal characteristics
We created a novel workflow by combining deep learning and double‐difference seismic imaging
New workflow provides better seismic catalog and larger amount of phase picks compared to human analysts
Fracture injection/shut-in tests are commonly used to measure the state of stress in the subsurface. Injection creates a hydraulic fracture (or in some cases, opens a preexisting fracture), and then ...the pressure after shut-in is monitored to identify fracture closure. Different interpretation procedures have been proposed for estimating closure, and the procedures sometimes yield significantly different results. In this study, direct, in-situ strain measurements are used to observe fracture reopening and closure. The tests were performed as part of the EGS Collab project, a mesoscale project performed at 1.25 and 1.5 km depth at the Sanford Underground Research Facility. The tests were instrumented with the SIMFIP tool, a double-packer probe with a high-resolution three-dimensional borehole displacement sensor. The measurements provide a direct observation of the fracture closure signature, enabling a high-fidelity estimate of the fracture closure stress (ie, the normal stress on the fracture). In two of the four tests, injection created an opening mode fracture, and so the closure stress can be interpreted as the minimum principal stress. In the other two tests, injection probably opened preexisting natural fractures, and so the closure stress can be interpreted as the normal stress on the fractures. The strain measurements are compared against different proposed methods for estimating closure stress from pressure transients. The shut-in transients are analyzed with two techniques that are widely used in the field of petroleum engineering – the ‘tangent’ method and the ‘compliance’ method. In three of the four tests, the tangent method significantly underestimates the closure stress. The compliance method is reasonably accurate in all four tests. Closure stress is also interpreted using two other commonly-used methods – ‘first deviation from linearity’ and the method of (Hayashi and Haimson, 1991). In comparison with the SIMFIP data, these methods tend to overestimate the closure stress, evidently because they identify closure from early-time transient effects, such as near-wellbore tortuosity. In two of the tests, microseismic imaging provides an independent estimate of the size of the fracture created by injection. When combined with a simple mass balance calculation, the SIMFIP stress measurements yield predictions of fracture size that are reasonably consistent with the estimates from microseismic. The calculations imply an apparent fracture toughness 2-3x higher than typical laboratory-derived values.
•Fracture injection/shut-in tests were performed with the SIMFIP tool, enabling strain-based measurements of fracture closure.•SIMFIP results can be compared with conventional methods of estimating closure pressure.•The ‘compliance method’ procedure for estimating closure pressure was reasonably accurate. The ‘tangent method’ was usually too low.•The ‘first deviation from linearity’ and the method of1 tended to overestimate closure pressure, evidently because of early-time transient effects.•Stress estimates were combined with mass balance calculations to estimate fracture size and compared with microseismic.
Enhanced Geothermal Systems could provide a substantial contribution to the global energy demand if their implementation could overcome inherent challenges. Examples are insufficient created ...permeability, early thermal breakthrough, and unacceptable induced seismicity. Here we report on the seismic response of a mesoscale hydraulic fracturing experiment performed at 1.5‐km depth at the Sanford Underground Research Facility. We have measured the seismic activity by utilizing a 100‐kHz, continuous seismic monitoring system deployed in six 60‐m length monitoring boreholes surrounding the experimental domain in 3‐D. The achieved location uncertainty was on the order of 1 m and limited by the signal‐to‐noise ratio of detected events. These uncertainties were corroborated by detections of fracture intersections at the monitoring boreholes. Three intervals of the dedicated injection borehole were hydraulically stimulated by water injection at pressures up to 33 MPa and flow rates up to 5 L/min. We located 1,933 seismic events during several injection periods. The recorded seismicity delineates a complex fracture network comprised of multistrand hydraulic fractures and shear‐reactivated, preexisting planes of weakness that grew unilaterally from the point of initiation. We find that heterogeneity of stress dictates the seismic outcome of hydraulic stimulations, even when relying on theoretically well‐behaved hydraulic fractures. Once hydraulic fractures intersected boreholes, the boreholes acted as a pressure relief and fracture propagation ceased. In order to create an efficient subsurface heat exchanger, production boreholes should not be drilled before the end of hydraulic stimulations.
Key Points
Mesoscale hydraulic fracturing in crystalline rock is observed with multigeophysical sensor array at close proximity
Created fracture network consists of multistrand hydraulic fractures and reactivated preexisting structures
Hydraulic fracture growth is strongly influenced by rock fabric, preexisting fractures, and stress heterogeneities
C8 myotome herpes zoster paresis Kreps, Carly E; Rynders, Sara D; Chhabra, A Bobby ...
The American journal of orthopedics (Belle Mead, N.J.)
41, Številka:
5
Journal Article
Recenzirano
Herpes zoster (HZ) infection is a reactivation of latent varicella zoster virus that causes pain and a rash in a dermatomal distribution. Previous reports suggest that 0.5-5% of HZ infections are ...associated with a myotomal paresis but the incidence may actually be much higher. We present a patient with HZ infection who had persistent right upper extremity weakness after resolution of the rash. Electrodiagnostic studies demonstrated decreased amplitudes in the median and ulnar nerves as well as denervation in the right C8 myotome. Repeat studies showed interval C8 reinnervation as well as normal nerve conduction studies.
•A new methodology for optimal design of a 3D borehole seismic array for microearthquake monitoring in anisotropic media.•Relationships between receiver distributions and standard deviation errors of ...hypocenter locations and focal mechanisms.•Hypocenter locations and focal mechanisms well reconstructed using three seismic receivers in each of six monitoring wells.
Multiple U.S. national laboratories, universities and industrial collaborators are conducting collaborative research under the EGS Collab project supported by the U.S. Department of Energy, to understand the fracture creation and imaging during fracturing in enhanced geothermal systems. Microearthquake hypocenter locations and focal mechanisms are used to monitor hydraulic fracturing growth and characterization at the EGS Collab experimental site at the Sanford Underground Research Facility using seismic receivers in multiple monitoring wells. We develop a methodology for optimal design a 3D borehole seismic array for cost-effective seismic monitoring in anisotropic media using not only the relationship between receiver distributions and standard deviation errors of microearthquake hypocenter locations, but also that between receiver distributions and focal-mechanism inversion errors. Our results indicate that microearthquake hypocenter locations and focal mechanisms can be reasonably well reconstructed for the EGS Collab Experiment I using six monitoring wells, including four fracture-parallel monitoring wells and two orthogonal wells. Eight seismic receivers evenly distributed in four parallel monitoring wells or twelve receivers in all six monitoring wells are required for hypocenter location, and twelve receivers evenly distributed in six wells or sixteen receivers in four wells are needed for focal-mechanism inversion.
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