Less Is More: The Physiological Basis for Tapering in Endurance, Strength, and Power Athletes

Taper, or reduced-volume training, improves competition performance across a broad spectrum of exercise modes and populations. This article aims to highlight the physiological mechanisms, namely in skeletal muscle, by which taper improves performance and provide a practical literature-based rationale for implementing taper in varied athletic disciplines. Special attention will be paid to strength- and power-oriented athletes as taper is under-studied and often overlooked in these populations. Tapering can best be summarized by the adage “less is more” because maintained intensity and reduced volume prior to competition yields significant performance benefits

Optimized reprocessing of documents using stored processor state

Variable Data Printing (VDP) allows customised versions of material such as advertising flyers to be readily produced. However, VDP is often extremely demanding of computing resources because, even when much of the material stays invariant from one document instance to the next, it is often simpler to re-evaluate the page completely rather than identifying just the portions that vary. In this paper we explore, in an XML/XSLT/SVG workflow and in an editing context, the reduction of the processing burden that can be realised by selectively reprocessing only the variant parts of the document. We introduce a method of partial re-evaluation that relies on re-engineering an existing XSLT parser to handle, at each XML tree node, both the storage and restoration of state for the underlying document processing framework. Quantitative results are presented for the magnitude of the speed-ups that can be achieved. We also consider how changes made through an appearance-based interactive editing scheme for VDP documents can be automatically reflected in the document view via optimised XSLT re-evaluation of sub-trees that are affected either by the changed script or by altered data

Tracking sub-page components in document workflows

Documents go through numerous transformations and intermediate formats as they are processed from abstract markup into final printable form. This notion of a document workflow is well established but it is common to find that ideas about document components, which might exist in the source code for the document, become completely lost within an amorphous, unstructured, page of PDF prior to being rendered. Given the importance of a component-based approach in Variable Data Printing (VDP) we have developed a collection of tools that allow information about the various transformations to be embedded at each stage in the workflow, together with a visualization tool that uses this embedded information to display the relationships between the various intermediate documents. In this paper, we demonstrate these tools in the context of an example document workflow but the techniques described are widely applicable and would be easily adaptable to other workflows and for use in teaching tools to illustrate document component and VDP concepts

Optimized reprocessing of documents using stored processor state

Variable Data Printing (VDP) allows customised versions of material such as advertising flyers to be readily produced. However, VDP is often extremely demanding of computing resources because, even when much of the material stays invariant from one document instance to the next, it is often simpler to re-evaluate the page completely rather than identifying just the portions that vary. In this paper we explore, in an XML/XSLT/SVG workflow and in an editing context, the reduction of the processing burden that can be realised by selectively reprocessing only the variant parts of the document. We introduce a method of partial re-evaluation that relies on re-engineering an existing XSLT parser to handle, at each XML tree node, both the storage and restoration of state for the underlying document processing framework. Quantitative results are presented for the magnitude of the speed-ups that can be achieved. We also consider how changes made through an appearance-based interactive editing scheme for VDP documents can be automatically reflected in the document view via optimised XSLT re-evaluation of sub-trees that are affected either by the changed script or by altered data

Fiber Type Profile and its Relation to Wilks Coefficient in Both Male and Female Powerlifters

While powerlifters tend to display higher fast-twitch fiber content, it is unknown if this content predicts competitive performance via Wilks coefficient. Purpose: to 1) compare the myosin heavy chain (MHC) fiber type (FT) profiles between powerlifters and sedentary controls of both sexes, and 2) determine if fast-twitch fiber content predicts Wilks coefficient. Methods: Twelve actively competing powerlifters (PL; n=6M/6F; age=21±1.0y; 3.0±1.8y competing; 7.3±6.6 meets attended) and ten sedentary controls (CON; n=5M/5F; age=19.4±2.0y) underwent vastus lateralis muscle biopsies, with samples analyzed for MHC isoform content via mixed homogenate SDS-PAGE. Individual MHC isoform differences between group and sex were analyzed using a 3x2x2 (FT [MHC I, IIa, & IIx] x group [PL & CON] x sex [male & female]) ANOVA and MHC IIa content was compared to Wilks coefficient using Pearson correlation coefficient at pResults: Male PL MHC isoform distribution was 50±6% I, 45±6% IIa, and 5±11% IIx, vs 46±6% I, 53±6 IIa, and 0% IIx in PL females. Conversely, male CON MHC distribution was 33±5% I, 38±7% IIa, and 30±8% IIx, vs 35±9% I, 44±8% IIa, and 21±17% IIx in CON females. Analysis revealed a significant FT main effect (pConclusions:These results illustrate powerlifters have higher MHC I and IIa proportions, as well as lower MHC IIx content compared to sedentary controls. While overall limited by sample size, MHC IIa content does not appear to be a significant predictor of powerlifting Wilks coefficient, suggesting this characteristic alone does not define powerlifter skill variations

Predicting the redshift 2 Halpha luminosity function using [OIII] emission line galaxies

Upcoming space-based surveys such as Euclid and WFIRST-AFTA plan to measure Baryonic Acoustic Oscillations (BAOs) in order to study dark energy. These surveys will use IR slitless grism spectroscopy to measure redshifts of a large number of galaxies over a significant redshift range. In this paper, we use the WFC3 Infrared Spectroscopic Parallel Survey (WISP) to estimate the expected number of Halpha (Ha) emitters observable by these future surveys. WISP is an ongoing HST slitless spectroscopic survey, covering the 0.8-1.65micron wavelength range and allowing the detection of Ha emitters up to z~1.5 and [OIII] emitters to z~2.3. We derive the Ha-[OIII] bivariate line luminosity function for WISP galaxies at z~1 using a maximum likelihood estimator that properly accounts for uncertainties in line luminosity measurement, and demonstrate how it can be used to derive the Ha luminosity function from exclusively fitting [OIII] data. Using the z~2 [OIII] line luminosity function, and assuming that the relation between Ha and [OIII] luminosity does not change significantly over the redshift range, we predict the Ha number counts at z~2 - the upper end of the redshift range of interest for the future surveys. For the redshift range 0.7<z<2, we expect ~3000 galaxies/deg^2 for a flux limit of 3x10^{-16} ergs/s/cm^2 (the proposed depth of Euclid galaxy redshift survey) and ~20,000 galaxies/deg^2 for a flux limit of ~10^{-16} ergs/s/cm^2 (the baseline depth of WFIRST galaxy redshift survey).Comment: Minor revisions to match accepted ApJ versio

Tendon Collagen Fibril Identification via Phase Contrast Microscopy

Tendons play a key role in the musculoskeletal system as their main functions are to connect muscles to bones, provide shock absorption, and increase range of motion and the efficiency of locomotion. Due to the tendons’ hierarchical structure, the ability to image subfibrillar units plays a key role in visualizing how changes at the microscopic level affect the macroscopic structure and function. PURPOSE: To provide an accessible method for confirming the separation of tendon tissue to the collagen fibril level. METHODS: Previously frozen (-80°C) 657BL/6J mouse tendons were treated with a chemical and mechanical extraction technique which led to the separation of the whole tendon to tendon subunits. The tendon complex was then imaged with phase contrast microscopy (PCM), which is an illumination technique under an optical microscope. Collagen fibrils were then confirmed with high-resolution imaging by atomic force microscopy (AFM). RESULTS: Quantitative analysis of the AFM images (n=38 fibril sections) revealed fibrils of 4 distinct sizes with an average D-banding period of 66 nm ± 2.1 and an average fibril height of 63 nm ± 23.5. CONCLUSION: The smallest subunits of the processed tendon complex visualized with PCM were confirmed to be collagen fibrils under high resolution imaging with the AFM. Quantitative analysis of AFM images revealed the 66 nm D-banding pattern in collagen fibrils of different sizes as described in previous literature. These findings provide a new method of confirming the presence of collagen fibrils utilizing an accessible mode of imaging and is applicable to tissue that has been previously frozen

Diterpenoids of terrestrial origin

Covering January to December 2017; previous review Nat. Prod. Rep., 2017, 34, 1233–1243. This review covers the isolation and chemistry of diterpenoids from terrestrial as opposed to marine sources and includes labdanes, clerodanes, abietanes, pimaranes, kauranes, cembranes and their cyclization products. There are 228 references

Modeling and mapping isotopic patterns in the Northwest Atlantic derived from loggerhead sea turtles

Stable isotope analysis can be used to infer geospatial linkages of highly migratory species. Identifying foraging grounds of marine organisms from their isotopic signatures is becoming de rigueur as it has been with terrestrial organisms. Sea turtles are being increasingly studied using a combination of satellite telemetry and stable isotope analysis; these studies along with those from other charismatic, highly vagile, and widely distributed species (e.g., tuna, billfish, sharks, dolphins, whales) have the potential to yield large datasets to develop methodologies to decipher migratory pathways in the marine realm. We collected tissue samples (epidermis and red blood cells) for carbon (delta C-13) and nitrogen (delta N-15) stable isotope analysis from 214 individual loggerheads (Caretta caretta) in the Northwest Atlantic Ocean (NWA). We used discriminant function analysis (DFA) to examine how well delta C-13 and delta N-15 classify loggerhead foraging areas. The DFA model was derived from isotopic signatures of 58 loggerheads equipped with satellite tags to identify foraging locations. We assessed model accuracy with the remaining 156 untracked loggerheads that were captured at their foraging locations. The DFA model correctly identified the foraging ground of 93.0% of individuals with a probability greater than 66.7%. The results of the external validation (1) confirm that assignment models based on tracked loggerheads in the NWA are robust and (2) provide the first independent evidence supporting the use of these models for migratory marine organisms. Additionally, we used these data to generate loggerhead-specific delta C-13 and delta N-15 isoscapes, the first for a predator in the Atlantic Ocean. We found a latitudinal trend of delta C-13 values with higher values in the southern region (20-25 degrees N) and a more complex pattern with delta N-15, with intermediate latitudes (30-35 degrees N) near large coastal estuaries having higher delta N-15-enrichment. These results indicate that this method with further refinement may provide a viable, more spatially-explicit option for identifying loggerhead foraging grounds

Behavioral phenotypes revealed during reversal learning are linked with novel genetic loci in diversity outbred mice.

Impulsive behavior and impulsivity are heritable phenotypes that are strongly associated with risk for substance use disorders. Identifying the neurogenetic mechanisms that influence impulsivity may also reveal novel biological insights into addiction vulnerability. Our past studies using the BXD and Collaborative Cross (CC) recombinant inbred mouse panels have revealed that behavioral indicators of impulsivity measured in a reversal-learning task are heritable and are genetically correlated with aspects of intravenous cocaine self-administration. Genome-wide linkage studies in the BXD panel revealed a quantitative trait locus (QTL) on chromosome 10, but we expect to identify additional QTL by testing in a population with more genetic diversity. To this end, we turned to Diversity Outbred (DO) mice; 392 DO mice (156 males, 236 females) were phenotyped using the same reversal learning test utilized previously. Our primary indicator of impulsive responding, a measure that isolates the relative difficulty mice have with reaching performance criteria under reversal conditions, revealed a genome-wide significant QTL on chromosome 7 (max LOD score = 8.73, genome-wide corrected