Rutile is a common accessory mineral that occurs in a wide spectrum of metamorphic rocks, such as in blueschists, eclogites, and granulites and as one of the most stable detrital heavy minerals in ...sedimentary rocks. The advent of rutile trace element thermometry has generated increased interest in a better understanding of rutile formation. This study documents important analytical advances in in situ LA-ICP-MS U/Pb geochronology of rutile: (1) Matrix matching, necessary for robust in situ dating is fulfilled by calibrating and testing several rutile standards (R10, R19, WH-1), including the presentation of new TIMS ages for the rutile standard R19 (489.5 +/- A 0.9 Ma; errors always stated as 2 s). (2) Initial common lead correction is routinely applied via Pb-208, which is possible due to extremely low Th/U ratios (usually < 0.003) in most rutiles. Employing a 213 nm Nd:YAG laser coupled to a quadrupole ICP-MS and using R10 as a primary standard, rutile U/Pb concordia ages for the two other rutile standards (493 +/- A 10 Ma for R19; 2640 +/- A 50 Ma for WH-1) and four rutile-bearing metamorphic rocks (181 +/- A 4 Ma for Ivrea metapelitic granulite; 339 +/- A 7 Ma for Saidenbach coesite eclogite; 386 +/- A 8 Ma for Fjortoft UHP metapelite; 606 +/- A 12 Ma for Andrelandia metepelitic granulite) always agree within 2% with the reported TIMS ages and other dating studies from the same localities. The power of in situ U/Pb rutile dating is illustrated by comparing ages of detrital rutile and zircon from a recent sediment from the Christie Domain of the Gawler Craton, Australia. While the U/Pb age spectrum from zircons show several pronounced peaks that are correlated with magmatic episodes, rutile U/Pb ages are marked by only one pronounced peak (at ca 1,675 Ma) interpreted to represent cooling ages of this part of the craton. Rutile thermometry of the same detrital grains indicates former granulite-facies conditions. The methods outlined in this paper should find wide application in studies that require age information of single spots, e.g., provenance studies, single-crystal zoning and texturally controlled dating.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The experience of cotherapy has been sparsely addressed in the literature. This qualitative study’s goals were to explore (a) the usefulness of cotherapy as a training model (b) the impact of ...cotherapy on services provided; (c) the impact of being trained in a cotherapy model; and (d) factors that both facilitated and hindered the process of cotherapy. The authors conducted a focus group interview with seven participants who graduated from a COAMFTE accredited MFT master’s program. Participants unanimously reported they believed cotherapy impacted client outcomes and training. They also expressed that cotherapists’ unwillingness to address issues within the cotherapy team negatively impacted the cotherapy relationship and client outcomes. Data analysis yielded four main themes, including cotherapy as a vehicle for personal growth, accountability in the cotherapy relationship, need for safety in the cotherapy relationship, and cotherapy team’s need for supervision.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The partitioning of rare earth elements (REE) between zircon, garnet and silicate melt was determined using synthetic compositions designed to represent partial melts formed in the lower crust during ...anatexis. The experiments, performed using internally heated gas pressure vessels at 7 kbar and 900–1000 °C, represent equilibrium partitioning of the middle to heavy REE between zircon and garnet during high‐grade metamorphism in the mid to lower crust. The DREE (zircon/garnet) values show a clear partitioning signature close to unity from Gd to Lu. Because the light REE have low concentrations in both minerals, values are calculated from strain modelling of the middle to heavy REE experimental data; these results show that zircon is favoured over garnet by up to two orders of magnitude. The resulting general concave‐up shape to the partitioning pattern across the REE reflects the preferential incorporation of middle REE into garnet, with DGd (zircon/garnet) ranging from 0.7 to 1.1, DHo (zircon/garnet) from 0.4 to 0.7 and DLu (zircon/garnet) from 0.6 to 1.3. There is no significant temperature dependence in the zircon–garnet REE partitioning at 7 kbar and 900–1000 °C, suggesting that these values can be applied to the interpretation of zircon–garnet equilibrium and timing relationships in the ultrahigh‐T metamorphism of low‐Ca pelitic and aluminous granulites.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Gait abnormalities such as Trendelenburg gait (TG) in patients who have hip osteoarthritis (OA) have traditionally been evaluated using clinicians’ visual assessment. Recent advances in portable ...inertial gait sensors offer more sensitive, quantitative methods for gait assessment in clinical settings. This study sought to compare sensor-derived metrics in a cohort of hip OA patients when stratified by clinical TG severity.
There were 42 patients who had hip OA and were grouped by TG severity (mild, moderate, and severe) through visual assessment by a single arthroplasty surgeon who had > 30 years of experience. After informed consent, wireless inertial sensors placed at the midpoint of the intercristal line collected gait parameters including pelvic shift, support time, toe-off symmetry, impact, and cadence. Clinical data on hip strength, range of motion, and Kellgren-Lawrence grade were collected.
Worsening TG severity had a higher mean Kellgren-Lawrence grade (2.5 versus 3.2 versus 3.4; P = .014) and reduced passive hip abduction (P = .004). Severe TG group demonstrated predominantly contralateral pelvic shift (n = 9 of 10, 90.0%), while ipsilateral shift was more frequently detected in moderate (n = 10 of 18, 55.6%) and mild groups (n = 9 of 14, 64.3%; P = .021). Contralateral single support time bias was greatest in severe TG (35.7% versus 50.0 versus 90.0%; P = .027). Asymmetric toe-off, impact, and support times were observed in all groups.
Traditional understanding of TG is that truncal shift occurs to the ipsilateral side. Using sensor-based measurements, the present study demonstrates a shift of the weight-bearing axis toward the contralateral side with increasing TG severity, which has not been previously described. Inertial sensors are feasible, quantitative gait measuring tools, and may reveal subtle patterns not readily discernible by traditional methods.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Separated longitudinal and transverse structure functions for the reaction 1H(e,e(')pi(+))n were measured in the momentum transfer region Q2 = 0.6--1.6 (GeV/c)(2) at a value of the invariant mass W = ...1.95 GeV. New values for the pion charge form factor were extracted from the longitudinal cross section by using a recently developed Regge model. The results indicate that the pion form factor in this region is larger than previously assumed and is consistent with a monopole parametrization fitted to very low Q2 elastic data.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Body mass index (BMI), American Society of Anesthesiologists (ASA) score, and Elixhauser Comorbidity Index are measures that are utilized to predict perioperative outcomes, though little is known ...about their comparative predictive effects. We analyzed the effects of these indices on costs, operating room (OR) time, and length of stay (LOS) with the hypothesis that they would have a differential influence on each outcome variable.
A retrospective review of the institutional database was completed on primary TKA patients from 2015 to 2018. Univariable and multivariable models were constructed to evaluate the strength of BMI, ASA, and Elixhauser comorbidities for predicting changes to total hospital and surgical costs, OR time, and LOS.
In total, 1313 patients were included. ASA score was independently predictive of all outcome variables (OR time, LOS, total hospital and surgical costs). BMI, however, was associated with intraoperative resource utilization through time and cost, but only remained predictive of OR time in an adjusted model. Total Elixhauser comorbidities were independently predictive of LOS and total hospital cost incurred outside of the operative theater, though they were not predictive of intraoperative resource consumption.
Although ASA, BMI, and Elixhauser comorbidities have the potential to impact outcomes and cost, there are important differences in their predictive nature. Although BMI is independently predictive of intraoperative resource utilization, other measures like Elixhauser and ASA score were more indicative of cost outside of the OR and LOS. These data highlight the differing impact of BMI, ASA, and patient comorbidities in impacting cost and time consumption throughout perioperative care.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study aims to establish evidence for the widespread existence of preserved high-resolution trace element variations in speleothems that may have climatic significance. Ion microprobe analysis of ...speleothems reveals that annual to sub-annual variations in element chemistry exist at five, shallow western European cave sites (Crag Cave, County Kerry and Ballynamintra, County Waterford, Ireland; Uamh an Tartair, Sutherland, Scotland; Grotte Pere-Noel, Belgium; Grotta di Ernesto, NE Italy) with widely varying climatic, geomorphic and geological settings. The variations are not restricted to species (Mg, Sr and Ba) known to substitute directly for Ca in the calcite lattice, but include H, F, Na and P. Phosphorus (as phosphate) displays the greatest variability and may have the most significance as a proxy for the seasonal temperature cycle because of its role as a nutrient element. The technique allows estimation of growth rate of speleothems at any interval of interest, which is one of several possible uses in palaeoclimatology.
The materials and techniques for both primary and revision total hip arthroplasty (THA) have changed over time. This study evaluated if the indications for revision THA, rates of components utilized ...(femoral or acetabulum, both, or head/liner exchange), length of stay (LOS), and payments to surgeons and facilities have also changed.
A retrospective study, utilizing the PearlDiver database, of 38,377 revision THA patients from January 2010 through December 2018 was performed. Data included the indication for revision, components revised (femoral or acetabulum, both, or head/liner exchange), LOS, and payments. Indications and components were analyzed by logistic regression (Dunnett’s post hoc test). Revision totals were analyzed with a linear regression model. Analysis of variance assessed changes in LOS and payments.
Patients’ median age was 67 years (Q1-Q3: 59-74), and 58.7% were female. Revisions for dislocation decreased between 2010 and 2018 (odds ratio OR 0.82, 95% confidence interval CI 0.68-0.98). Revisions for component loosening increased (OR 1.54, 95% CI 1.25-1.91). Dislocation remained the most common indication (19.3%), followed by PJI (17.3%) and loosening (17.1%). Both-component (OR:1.45; 95% CI:1.25-1.67) and femoral component only revisions increased; acetabular component only and head/liner exchanges decreased. Acetabular (OR 0.57, 95% CI 0.47-0.70) and head/liner exchange (OR 0.29, 95% CI 0.20-0.43) revisions decreased, while both component exchange (OR 1.45, 95% CI 1.25-1.67) and femoral revisions (OR 1.17, 95% CI 0.99-1.37) increased. Average LOS (−0.68 days; P < .001) and surgeon payments decreased (−$261.8; P < .001) while facility payments increased ($4,211; P < .001).
Indications for revision THA in this database study changed over time, with revision for dislocation decreasing and revision for loosening increasing over time. Both component and femoral revisions increased, and acetabular component and head/liner exchanges decreased. It is possible that these associations could be attributed to a number of details, the method of femoral fixation, surgical approach, and cementing, all of which require additional study.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Secondary ionization mass spectrometry (SIMS) U/Pb dating of zircon has been applied to rocks of the Lewisian Complex of South Harris (Outer Hebrides, NW Scotland), yielding insights into the complex ...geological evolution of this region and enhancing our understanding of terranes in the Lewisian Gneiss Complex. Results show that tonalite - trondhjemite - granodiorite magmatism occurred in the Tarbert Terrane between c. 2850 and 2830 Ma, equivalent to similar rocks in other parts of the Outer Hebrides. Magmatism was accompanied or closely followed by high-grade metamorphism at c. 2830 Ma, the first reported occurrence of such an event at this time. These rocks were affected by a subsequent high-grade metamorphic event at c. 2730 Ma, which has correlatives both in the Outer Hebrides and in the mainland Lewisian Gruinard Terrane. These data suggest that the "terranes" forming the Outer Hebrides and parts of the mainland Lewisian were once contiguous and were fragmented by post-2730 Ma events. The c. 1700-1660 Ma ages from felsic sheets and pegmatites within the Langavat Shear Zone may record the reassembly of these crustal fragments.
When colonizing new regions, invading species might compete strongly with phylogenetically related species native to the regions they are colonizing, eventually leading to coexistence or ...displacement. In the southeast of the United States, recently established coyotes (Canis latrans) compete with red fox (Vulpes vulpes) and gray fox (Urocyon cinereoargenteus), although it remains unclear if competition is leading to resource partitioning or displacement by species. Using nitrogen and carbon stable isotopes, we tested the hypothesis that coyotes compete with foxes for food resources, with canids partitioning those resources to mitigate competition. We compared diets of canids in the southeast to those in the Plains region of the United States, a region where all three species historically have coexisted. We analyzed 217 hair samples from both regions pre-1960, prior to coyote colonization of the southeast, and post-2000, after coyotes were ubiquitous there, to assess differences in diet among species for both regions (southeast versus Plains and time periods, pre- versus postcolonization by coyotes). Modeling revealed significant dietary overlap among historical and contemporary populations in the southeast. Historically, all species partitioned resources in the Plains. Contemporarily, red fox and coyotes co-occurring in the Plains overlapped in diet; however, gray fox diet did not overlap with those of red fox and coyotes. Absence of partitioning in diet among co-occurring canids in the southeast indicates that interspecific competition could be strong in the region. Competition among canid populations in the southeast could lead to further resource partitioning among species that promotes coexistence or competitive exclusion of smaller fox species where coyote populations are abundant.
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