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Due to its inaccessibility, no complete and coherent data set exists for the composition of modern fast‐spreading oceanic crust. We sampled outcrops through 6,500 m of fossil oceanic crust in the Oman Ophiolite (Wadi Gideah Transect) that is regarded as best analogue of fast‐spreading crust on land. Here we report a complete set of whole‐rock major and trace element data displaying systematic and contrasting compositional trends in lower and upper gabbros being correlated with stratigraphic depth. A significant discontinuity in crystallization regime is observed at ∼3,525 m above the mantle‐crust boundary: gabbros below ∼3,525 m have in general very low incompatible element mass fractions which develop upwards in a barely noticeable way to more differentiated compositions while Mg# decreases. More pronounced trends indicating progressive fractionation of ascending melts can be observed for incompatible elements and their element ratios as a consequence of in situ crystallization. Locally, more variable compositions within narrow depth intervals testify for advanced differentiation in situ within individual sills. Gabbros above ∼3,525 m become significantly more evolved and show considerable variations in composition. Fractional crystallization and mixing processes in a transient axial melt lens control the composition of isotropic “varitextured” gabbros and sheeted dike basalts where fractionation of high field strength elemental ratios is minor. New average compositions of fast‐spread (paleo) oceanic crust are reported for major and 38 trace elements. Comparison with new data from Wadi Khafifah close to Wadi Gideah suggests robustness of crustal accretion processes in both space and time. Oceanic crust covers more than two‐thirds of Earth's surface but, due to limited accessibility, no single coherent compositional profile that would allow for understanding the processes how oceanic crust is formed has been obtained up to now. We sampled a transect through 6.5 km of fossil lower oceanic crust of the Samail ophiolite (Sultanate of Oman, Wadi Gideah) that is regarded as best analogue of fast‐spreading oceanic crust on land, and analyzed all samples with a wide selection of techniques. Here, we present whole rock data and see systematic compositional trends correlating with stratigraphic depth. Distribution trends of incompatible trace elements suggest that lower, layered gabbros are made of cumulus crystals that crystallize in situ, separating from the ascending parental magma. We also find gabbros with variable compositions at intermediate depth intervals that could originate from melts crystallizing and differentiating in sills. In contrast, compositions of upper non‐layered gabbros above ∼3,525 m above the mantle‐crust boundary are controlled by fractional crystallization and mixing processes in transient melt lenses. New average compositions of (paleo) oceanic crust are reported for major and 38 trace elements. Comparison with new data from Wadi Khafifah close to Wadi Gideah suggests robustness of accretion processes in both space and time. A coherent compositional transect through fossil oceanic crust for major and 38 trace elements, compositions for Samail oceanic crustSystematic but contrasting compositional trends correlate with stratigraphic depth over 6,500 m of plutonic crustA discontinuity at ～3,525 m above Moho separates lower cumulate gabbros crystallized in situ from upper gabbros fractionated in melt lens A coherent compositional transect through fossil oceanic crust for major and 38 trace elements, compositions for Samail oceanic crust Systematic but contrasting compositional trends correlate with stratigraphic depth over 6,500 m of plutonic crust A discontinuity at ～3,525 m above Moho separates lower cumulate gabbros crystallized in situ from upper gabbros fractionated in melt lens

Oceanic gabbros are the most abundant rocks close to Earth's surface. Here we present new data from a consistent profile through the paleocrust of the Samail Ophiolite (Oman), which is thought to provide the best analog for modern fast‐spreading oceanic crust. Incompatible trace elements of co‐existing plagioclase and clinopyroxene fractionate from the mineral core to rim and up section from layered to foliated to varitextured gabbros. Layered gabbro parental melts correspond to mid‐ocean‐ridge basalts (MORB), and plagioclase Ca# shows a pronounced inverse zonation. Likely, they crystallized in situ from hydrous melts, compositionally buffered by replenishment at equilibrium to MORB and near steady‐state boundary conditions. Further upsection, the compositional variability increases. Foliated gabbro rim and core compositions indicate increased fractionation and disequilibrium to MORB, triggered by open‐system fractional crystallization within a heterogeneous magma plumbing structure, characterized by magma mixing, varying ambient water activities, and boundary conditions. Varitextured gabbros are chemically diverse with parental melts partially more primitive than MORB, suggesting that primitive melts directly reach the axial melt lens (AML). REE‐in‐plagioclase‐clinopyroxene thermometry compared to and supported by anorthite‐in‐plagioclase thermometry reveals a relationship of TREEAn${T}_{\text{REE}}^{\text{An}}$[°C] = 6.1 ± 0.2 × An + 706 ± 19. Crystallization temperatures of the layered gabbros cover a narrow range of 1216 ± 14°C. Considerable temperature variability of 1077–1231°C is observed further upsection, featuring a thermal minimum within the foliated gabbros. This minimum is assumed to represent a zone where the fractionated descending crystal mushes originating from the AML meet with evolved liquids expelled from deeper crustal levels. Our findings suggest hybrid accretion of fast‐spread crust. Oceanic crust, the crystalline basement beneath the ocean‐floor sediments is difficult to be sampled by shipboard drilling operations, but can be obducted onto continents by tectonic movement of lithospheric crustal fragments to form ophiolites. These rock formations serve as an analog to in‐situ crust. They can be samples along a profile from extrusive basaltic rocks to gabbros to the upper mantle giving access to the earth's interior. The geochemical and thermal evolution along a profile of paleocrust is crucial for gaining knowledge of the crust's accretional dynamics and formation processes. Our data suggest that the lower part the layered gabbros, are formed by a fundamentally different process than the upper foliated, and varitextured gabbros. While geochemical signatures systematically evolve upsection and the temperature structure is homogeneous for the lower part, the upper part is characterized by much higher dynamics and lower crystallization temperatures. Therefore, the crust forms in a hybrid process, where the lower part is dominated by near steady‐state in situ crystallization in equilibrium with the parental melt. The upper part is formed in a more heterogeneous environment, dominated by subsiding crystal mushes, which mix with more primitive melts under disequilibrium conditions, yielding enhanced chemical variability. Geochemical profiles reveal continuous evolution of incompatible elements for the layered, and diverse fractionation for the upper gabbrosREE and anorthite thermometry shows a homogenous temperature structure for the lower, and a variable temperature record for the upper crustBoth suggests a hybrid model, with lower crust replenished in situ accretion and upper crust melt mixing and variable equilibrium dynamics Geochemical profiles reveal continuous evolution of incompatible elements for the layered, and diverse fractionation for the upper gabbros REE and anorthite thermometry shows a homogenous temperature structure for the lower, and a variable temperature record for the upper crust Both suggests a hybrid model, with lower crust replenished in situ accretion and upper crust melt mixing and variable equilibrium dynamics

Abstract: The problem of estimating the numbers of motor units N in a muscle is embedded in a general stochastic model using the notion of thinning from point process theory. In the paper a new moment type estimator for the numbers of motor units in a muscle is denned, which is derived using random sums with independently thinned terms. Asymptotic normality of the estimator is shown and its practical value is demonstrated with bootstrap and approximative confidence intervals for a data set from a 31-year-old healthy right-handed, female volunteer. Moreover simulation results are presented and Monte-Carlo based quantiles, means, and variances are calculated for N ∈{300,600,1000}. [Copyright &y& Elsevier]

Many applications of regression models involve ordinal categorical predictors. Two common approaches for handling ordinal predictors are to form a set of dummy variables, or employ a two stage approach where dimension reduction is first applied and then the response is regressed against the predicted latent indices. Both approaches have drawbacks, with the former running into a high-dimensional problem especially if interactions are considered, while the latter separates the prediction of the latent indices from the construction of the regression model. To overcome these challenges, a new approach called the LASSO on Latent Indices (LoLI) for handling ordinal predictors in regression is proposed, which involves jointly constructing latent indices for each or for groups of ordinal predictors and modeling the response directly as a function of these. LoLI borrows strength from the response to more accurately predict the latent indices, leading to better estimation of the corresponding effects. Furthermore, LoLI incorporates a LASSO type penalty to perform hierarchical selection, with interaction terms selected only if both parent main effects are included. Simulations show that LoLI can outperform the dummy variable and two stage approaches in selection and prediction performance. Applying LoLI to an Australian household-based panel identified three dimensions of psychosocial workplace quality (job demands, stress, and security) which affect an individual's mental health in an additive and pairwise interactive manner. [ABSTRACT FROM AUTHOR]

Using commercially available microarray technology, we investigated a series of transcriptional adaptations caused by atrophy of rat m. soleusdue to 35 days of hindlimb suspension. We detected 395 out of 1,200 tested transcripts, which reflected 1%–5% of totally expressed genes. From various cellular functional pathways, we detected multiple genes that spanned a 200‐fold range of gene expression levels. Statistical analysis combining L1 regression with the sign test based on the conservative Bonferroni correction identified 105 genes that underwent transcriptional adaptations with atrophy. Generally, expressional changes were discrete (<50%) and pointed in the same direction for genes belonging to the same cellular functional units. In particular, a distinct expressional adaptation of genes involved in fiber transformation; that is, metabolism, protein turnover, and cell regulation were noted and matched to corresponding transcriptional changes in nutrient trafficking. Expressional changes of extracellular proteases, and of genes involved in nerve‐muscle interaction and excitation‐contraction coupling identify previously not recognized adaptations that occur in atrophic m. soleus. Considerations related to technical and statistical aspects of the array approach for profiling the skeletal muscle genome and the impact of observed novel adaptations of the m. soleustranscriptome are put into perspective of the physiological adaptations occurring with muscular atrophy.