Acute and chronic exercise in patients with HFrEF: Evidence of structural and functional plasticity and intact angiogenic signaling in skeletal muscle

This study examined the response to acute submaximal exercise and the effect of training in patients with heart failure with reduced ejection fraction (HFrEF). The acute angiogenic response to submaximal exercise in HFrEF after small muscle mass training is debated. The direct Fick method, with vascular pressures, was performed across the leg during knee-extensor exercise (KE) at 50% of maximum work rate (WRmax) in patients (n = 6) and controls (n = 6) and then after KE training in patients. Muscle biopsies facilitated the assessment of skeletal muscle structure and vascular endothelial growth factor (VEGF) mRNA levels. Prior to training, HFrEF exhibited significantly higher leg vascular resistance (LVR) (approximate to 15%) and significantly greater noradrenaline spillover (approximate to 385%). Apart from mitochondrial volume density, which was significantly lower (approximate to 22%) in HFrEF, initial skeletal muscle structure, including capillarity, was not different between groups. Resting VEGF mRNA levels, and the increase with exercise, was not different between patients and controls. Following training, LVR was no longer elevated and noradrenaline spillover was curtailed. Skeletal muscle capillarity increased with training, as assessed by capillary-to-fibre ratio (approximate to 13%) and number of capillaries around a fibre (N-CAF) (approximate to 19%). VEGF mRNA was now not significantly increased by acute exercise. Muscle fibre cross-sectional area and percentage area of type I fibres both increased significantly with training (approximate to 18% and approximate to 21%, respectively), while the percentage area of type II fibres fell significantly (approximate to 11%), and mitochondrial volume density now exceeded that of controls. These data reveal structural and functional plasticity and appropriate angiogenic signalling in skeletal muscle of HFrEF patients

Vale of York 3-D borehole interpretation and cross-sections study

The Vale of York between Doncaster and Scunthorpe in the south and York and Bugthorpe in the north is largely underlain by bedrock of the Sherwood Sandstone Group – one of the regions principal aquifers. Significant superficial deposits of Quaternary age overlie the Sherwood Sandstone. This study aims to investigate the nature of these superficial deposits with respect to their relationship with the underlying aquifer. The Vale of York project area represents a varied glaciated terrain, consisting of pro-glacial finegrained sediments, coarser glaciofluvilal sediments and extensive glacial tills. These diverse superficial units vary in thickness throughout the project area. The hydrogeological nature of the natural superficial sequence is consequently highly variable. Units may be considered as aquitards, while others may act as aquifers, providing a potential pathway to the underlying sandstone. The classification of lithologies as aquifer or aquitard is described in detail in this report. To investigate the hydrogeological nature of the superficial sequence, six east-west and three north-south lithostratigraphical cross-sections were constructed. A range of geoscientific information was considered, including existing geological mapping and over 3000 fully attributed and coded boreholes. The cross-sections show a subdivision of the superficial sequence into lithostratigraphical units. Each unit is described in detail in this report. In addition, a series of thematic maps were generated from the lithological component of the digital borehole data. Total superficial aquifer and superficial aquitard maps show how the lithological nature of the superficial sequence varies across the area. Rockhead elevation and superficial thickness maps indicate where the sandstone aquifer outcrops at the ground surface. In summary, four main lithostratigraphical units overlie the Sherwood Sandstone Group aquifer in the project area: a basal sequence of glaciofluvial sand and gravel (interpreted as a superficial aquifer), glaciolacustrine laminated silt & clay (aquitard), glacial till comprising sandy gravelly clay (aquitard), and a cover sequence of fluvial and aeolian sand, clay and peat (aquifer / aquitard). The correlations illustrate that in certain areas, superficial deposits are thin or absent and that in these areas the Sherwood Sandstone aquifer comes directly to ground surface

How to Open the Treasure Chest? Optimising DNA Extraction from Herbarium Specimens

Herbarium collections are potentially an enormous resource for DNA studies, but the use of herbarium specimens in molecular studies has thus far been slowed down by difficulty in obtaining amplifiable DNA. Here we compare a set of commercially available DNA extraction protocols and their performance in terms of DNA purity and yield, and PCR amplification success as measured by using three differentially sized markers, the rbcL barcoding marker (cpDNA), the LEAFY exon 3 (nrDNA), and the trnL(UAA) P6 loop (cpDNA). Results reveal large differences between extraction methods, where DNA purity rather than yield is shown to be strongly correlated with PCR success. Amplicon size shows similarly strong correlation with PCR success, with the shortest fragment showing the highest success rate (78%, P6 loop, 10–143 base pairs (bp)) and the largest fragment the lowest success (10%, rbcL, 670 bp). The effect of specimen preparation method on PCR success was also tested. Results show that drying method strongly affects PCR success, especially the availability of fragments longer than 250 bp, where longer fragments are more available for PCR amplification in air dried material compared to alcohol dried specimens. Results from our study indicate that projects relying on poor-quality starting material such as herbarium or scat samples should focus on extracting pure DNA and aim to amplify short target regions

In vivo and in vitro evidence that intrinsic upper- and lower-limb skeletal muscle function is unaffected by ageing and disuse in oldest-old humans

Aim: To parse out the impact of advanced ageing and disuse on skeletal muscle function, we utilized both in vivo and in vitro techniques to comprehensively assess upper- and lower-limb muscle contractile properties in 8 young (YG; 25 6 years) and 8 oldest-old mobile (OM; 87 5 years) and 8 immobile (OI; 88 4 years) women. Methods: In vivo, maximal voluntary contraction (MVC), electrically evoked resting twitch force (RT), and physiological cross-sectional area (PCSA) of the quadriceps and elbow flexors were assessed. Muscle biopsies of the vastus lateralis and biceps brachii facilitated the in vitro assessment of single fibre-specific tension (Po). Results: In vivo, compared to the young, both the OM and OI exhibited a more pronounced loss of MVC in the lower limb [OM (60%) and OI (75%)] than the upper limb (OM = 51%; OI = 47%). Taking into account the reduction in muscle PCSA (OM = 10%; OI = 18%), only evident in the lower limb, by calculating voluntary muscle-specific force, the lower limb of the OI (40%) was more compromised than the OM (13%). However, in vivo, RT in both upper and lower limbs (approx. 9.8 N m cm 2) and Po (approx. 123 mN mm 2), assessed in vitro, implies preserved intrinsic contractile function in all muscles of the oldest-old and were well correlated (r = 0.81). Conclusion: These findings suggest that in the oldest-old, neither advanced ageing nor disuse, per se, impacts intrinsic skeletal muscle function, as assessed in vitro. However, in vivo, muscle function is attenuated by age and exacerbated by disuse, implicating factors other than skeletal muscle, such as neuromuscular control, in this diminution of function. Keywords in vitro, in vivo, oldest-old, sarcopeni

Case-Analysis for Rippling and Inductive Proof

Rippling is a heuristic used to guide rewriting and is typically used for inductive theorem proving. We introduce a method to support case-analysis within rippling. Like earlier work, this allows goals containing if-statements to be proved automatically. The new contribution is that our method also supports case-analysis on datatypes. By locating the case-analysis as a step within rippling we also maintain the termination. The work has been implemented in IsaPlanner and used to extend the existing inductive proof method. We evaluate this extended prover on a large set of examples from Isabelle’s theory library and from the inductive theorem proving literature. We find that this leads to a significant improvement in the coverage of inductive theorem proving. The main limitations of the extended prover are identified, highlight the need for advances in the treatment of assumptions during rippling and when conjecturing lemmas

Total photoproduction cross-section at very high energy

In this paper we apply to photoproduction total cross-section a model we have proposed for purely hadronic processes and which is based on QCD mini-jets and soft gluon re-summation. We compare the predictions of our model with the HERA data as well as with other models. For cosmic rays, our model predicts substantially higher cross-sections at TeV energies than models based on factorization but lower than models based on mini-jets alone, without soft gluons. We discuss the origin of this difference.Comment: 13 pages, 9 figures. Accepted for publication in EPJC. Changes concern added references, clarifications of the Soft Gluon Resummation method used in the paper, and other changes requested by the Journal referee which do not change the results of the original versio

Iron valence in double-perovskite (Ba,Sr,Ca)2FeMoO6: Isovalent substitution effect

In the Fe-Mo based B-site ordered double-perovskite, A2FeMoO6.0, with iron in the mixed-valence II/III state, the valence value of Fe is not precisely fixed at 2.5 but may be fine-tuned by means of applying chemical pressure at the A-cation site. This is shown through a systematic 57Fe Mossbauer spectroscopy study using a series of A2FeMoO6.0 [A = (Ba,Sr) or (Sr,Ca)] samples with high degree of Fe/Mo order, the same stoichiometric oxygen content and also almost the same grain size. The isomer shift values and other hyperfine parameters obtained from the Mossbauer spectra confirm that Fe remains in the mixed-valence state within the whole range of A constituents. However, upon increasing the average cation size at the A site the precise valence of Fe is found to decrease such that within the A = (Ba,Sr) regime the valence of Fe is closer to II, while within the A = (Sr,Ca) regime it is closer to the actual mixed-valence II/III state. As the valence of Fe approaches II, the difference in charges between Fe and Mo increases, and parallel with this the degree of Fe/Mo order increases. Additionally, for the less-ordered samples an increased tendency of clustering of the anti-site Fe atoms is deduced from the Mossbauer data.Comment: 19 pages, 6 figures, submitted to Phys. Rev.

The Ties that Double Bind Us: Career, Emotion and Narrative Coping in Difficult Working Relationships

This article examines through an autoethnographic account how career aspirations and constraints may lead individuals to endure emotionally aversive situations. It presents evidence that individuals in such situations engage in emotion‐focused coping through narrative, illustrated by the author’s autoethnographic narrative of a difficult working relationship which developed into a double bind situation. The paper suggests that narrative coping in response to a double bind can actually serve to reify and prolong such situations. The paper concludes that autoethnographic research does not lend itself to simple organisational solutions. Possible avenues for further research are outlined and discussed