Compositional and Dynamic Controls on Mafic—Silicic Magma Interactions at Continental Arc Volcanoes: Evidence from Cordón El Guadal, Tatara-San Pedro Complex, Chile

Heterogeneous andesitic and dacitic lavas on Cordón El Guadal bear on the general problem of how magmas of differing compositions and physical properties interact in shallow reservoirs beneath continental arc volcanoes. Some of the lavas contain an exceptionally large proportion (<40%) of undercooled basaltic andesitic magma in various states of disaggregation. Under-cooled mafic magma occurs in the silicic lavas as large (<40 cm) basaltic andesitic magmatic inclusions, as millimeter-sized crystal-clots of Mg-rich olivine phenocrysts plus adhering Carich plagioclase microphenocrysts (An50-70), and as uniformly distributed, isolated phenocrysts and microphenocrysts. Compositions and textures of plagioclase phenocrysts indicate that inclusion-forming magmas are hybrids formed by mixing basaltic and dacitic melts, whereas textural features and compositions of groundmass phases indicate that the andesitic and dacitic lavas are largely mechanical mixtures of dacitic magma and crystallized basaltic andesitic magma. This latter observation is significant because it indicates that mechanical blending of undercooled mafic magma and partially crystallized silicic magma is a possible mechanism for producing the common porphyritic texture of many calc-alkaline volcanic rocks. The style of mafic-silicic magma interaction at Cordon El Guadal was strongly dependent upon the relative proportions of the endmembers. Equally important in the Guadal system, however, was the manner in which the contrasting magmas were juxtaposed. Textural evidence preserved in the plagioclase phenocrysts indicates that the transition from liquid-liquid to solid-liquid mixing was not continuous, but was partitioned into periods of magma chamber recharge and eruption, respectively. Evidently, during periods of recharge, basaltic magmas rapidly entrained small amounts of dacitic magma along the margins of a turbulent injection fountain. Conversely, during periods of eruption, dacitic magma gradually incorporated small parcels of basaltic andesitic magma. Thus, the coupled physical-chemical transition from mixed inclusions to commingled lavas is presumably not coincidental. More likely, it probably provides a partial record of the dynamic processes occurring in shallow magma chambers beneath continental are volcanoe

Clinical measurements versus patient-reported outcomes: analysis of the American Shoulder and Elbow Surgeons physician assessment in patients undergoing reverse total shoulder arthroplasty.

BackgroundThe American Shoulder and Elbow Surgeons (ASES) score is composed of a patient-reported portion and a physician assessment. Although the patient-reported score is frequently used to assess postoperative outcomes after shoulder arthroplasty, no previous studies have used the physician-assessment component. This study evaluated the relationship of the ASES physician-assessment measurements with patient-reported shoulder and general health outcomes.MethodsA retrospective review of a prospectively collected multicenter database was used to analyze patients who underwent primary reverse total shoulder arthroplasty (RTSA) from 2012 to 2015 with a minimum 2-year follow-up. ASES physician-assessment and patient-reported components and 12-Item Short Form Health Survey (SF-12) general health questionnaires were obtained preoperatively and 2 years postoperatively. The relationship between ASES physician measurements with ASES patient-reported outcome (PRO) scores and SF-12 Physical and Mental domain scores was assessed with Pearson correlation coefficients.ResultsIncluded were 74 patients (32 men; mean age, 69.2 years; body mass index, 29.4 kg/m2). Preoperative physician measurements and PRO scores were not significantly correlated. Postoperatively, only the ASES physician-measured active (R = 0.54, P &lt; .01) and passive forward flexion (R = 0.53, P &lt; .01) demonstrated moderate correlation with ASES patient scores. The remaining clinical measurements had no significant correlations with ASES patient or SF-12 scores. During the 2-year period, only improvements in active forward flexion correlated with improvements in ASES patient scores (R = 0.36, P &lt; .01).ConclusionsLittle correlation exists between clinical measurements from the ASES physician component and PROs, including the ASES patient-reported and SF-12 general health surveys, in RTSA patients. Improvement in active forward flexion is the only clinical measurement correlated with PRO improvement at 2 years

Do Outcomes of Arthroscopic Subscapularis Tendon Repairs Depend on Rotator Cuff Fatty Infiltration?

Background:Rotator cuff fatty infiltration has been correlated with poorer radiographic and clinical outcomes in supraspinatus and infraspinatus tendon repairs, but this has not been well-studied in subscapularis tendon repairs. Purpose:To evaluate the influence of preoperative rotator cuff fatty infiltration on postoperative outcomes for patients undergoing arthroscopic subscapularis tendon repair. Study Design:Cohort study; Level of evidence, 3. Methods:Patients who underwent arthroscopic subscapularis repair between 2010 and 2016 were retrospectively identified, and demographic data and surgical findings were recorded. The extent of fatty infiltration was determined on preoperative magnetic resonance imaging by the Fuchs modification of the Goutallier classification. At the most recent follow-up, patients completed the Patient-Reported Outcomes Measurement Information System for Upper Extremity (PROMIS-UE) computer adaptive test and a postoperative visual analog scale for pain. The distribution of fatty infiltration was compared between patients undergoing subscapularis tendon repair versus subscapularis tendon repair combined with a posterior cuff repair. Outcomes were compared for patients using Goutallier grade 0-1 versus grade ≥2 changes in each rotator cuff muscle. Multivariate linear regression analysis was performed to evaluate the influence of muscle quality, as well as demographic factors, on PROMIS-UE scores. Significance was defined as P &lt; .05. Results:There were 140 shoulders included (mean age, 61.8 years; 42.1% female; mean follow-up, 51.7 months). The prevalence of Goutallier grade 2 changes or higher was significantly greater in patients with multitendon repair relative to isolated subscapularis tendon repair. For the overall group of all patients undergoing subscapularis tendon repair, whether in isolation or as part of a multitendon repair, PROMIS-UE scores were significantly lower for patients with infraspinatus muscle grade 2 or higher Goutallier changes relative to grade 0 or 1. After adjustment for age, body mass index, patient sex, and fatty infiltration in other rotator cuff muscles, poor infraspinatus muscle quality remained the only significant predictor for lower PROMIS-UE scores. Conclusion:Patients undergoing arthroscopic subscapularis tendon repair with poor infraspinatus muscle quality had worse patient-reported outcomes. This was true whether subscapularis tendon repair was isolated or was performed in conjunction with supraspinatus and infraspinatus tendon repairs

Automated Data Management Information System (ADMIS)

ADMIS stores and controls data and documents associated with manned space flight effort. System contains all data oriented toward a specific document; it is primary source of reports generated by the system. Each group of records is composed of one document record, one distribution record for each recipient of the document, and one summary record

Tibial Tubercle Osteotomy and Medial Patellofemoral Ligament Imbrication for Patellar Instability Due to Trochlear Dysplasia.

BackgroundThe treatment of patellar instability in the setting of trochlear dysplasia is challenging.Purpose/hypothesisThe purpose of this study was to evaluate outcomes for the treatment of recurrent patellar dislocations due to trochlear dysplasia using anteromedialization tibial tubercle osteotomy combined with medial patellofemoral ligament (MPFL) imbrication. We hypothesized that the treatment of patellar instability with tibial tubercle osteotomy and MPFL imbrication would result in improved patient satisfaction and decrease patellar instability events in patients with prior instability and trochlear dysplasia.Study designCase series; Level of evidence, 4.MethodsWe performed a retrospective analysis of patients who underwent MPFL imbrication and concomitant anteromedialization tibial tubercle osteotomy for recurrent patellofemoral instability at a single institution. The minimum follow-up was 1 year. Patient demographic information including age at the time of surgery, sex, body mass index (BMI), tibial tubercle-trochlear groove (TT-TG) distance, and grade of trochlear dysplasia was collected along with relevant operative data. Postoperatively, recurrent dislocation events as well as Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index, and Kujala scores were collected, and satisfaction was ascertained by asking patients whether they would undergo the procedure again.ResultsA total of 37 knees from 31 patients (23 female) with a mean follow-up of 3.8 years (range, 1-8.9 years) were included. The mean patient age was 28.8 years (range, 14-45 years), the mean BMI was 24 kg/m2 (range, 20-38 kg/m2), and the mean preoperative TT-TG distance was 18.9 mm (range, 8.4-32.4 mm). Two knees were classified as low-grade trochlear dysplasia (Dejour A) and 35 as high-grade trochlear dysplasia (Dejour B-D). At final follow-up, patients reported mean KOOS subscale scores of 86.5 (Pain), 79.8 (Symptoms), 93.9 (Activities of Daily Living), 74.3 (Sports/Recreation), and 61.9 (Quality of Life), as well as a mean Kujala score of 81.3. Mean patient satisfaction was 8.3 of 10. The majority of knees (86.5%; 32/37) remained stable without recurrent instability after this procedure, while 13.5% (5 knees) suffered a recurrent dislocation, with 2 requiring revision surgery. Eight knees (21.6%) underwent subsequent hardware removal.ConclusionAnteromedialization tibial tubercle osteotomy with MPFL imbrication can improve recurrent patellofemoral instability and provide significant clinical benefit to patients with trochlear dysplasia

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Narratives of urban female adolescents in South Africa: dietary and physical activity practices in an obesogenic environment

Objectives: The objectives of this study were to investigate the narratives pertaining to dietary and physical activity practices by female adolescents in Soweto.Design: This was exploratory qualitative research, using duo interviews (pairs of best friends) (n = 29) from adolescent females.Setting: The setting was three urban high schools in the township of Soweto, South Africa.Subjects: Subjects were twenty-nine pairs of Grade 12 female adolescents predominantly, with a mean age of 18 years (15.3-21.6, standard deviation 1.1).Outcome measures: The outcome measure was body mass index, interpreted in relation to eating practices and exercise participation.Results: Locally prepared convenience foods were reported to replace home-prepared breakfast. The majority of participants did not prioritise eating breakfast at home, but purchased deep-fried dough balls (“fat” cakes) from vendors before school. Lunch boxes were also not commonly used as participants preferred to use spending money to purchase food from the school tuck shop. Kotas, “fat” cakes and snacks were popular lunch choices because of their affordability, convenience, peer influence and popularity. Respondents engaged in minimal active recreationalactivities. A lack of facilities and concerns about safety were barriers to activity.Conclusion: This study highlights the importance of investigating the immediate social context as a potential intervention point to improve the lifestyle of adolescents, to enable them to make the affordable and convenient choice, the healthier choice. Keywords: adolescent, eating, consumption, nutrition, physical activity, obesity, urban, South Afric