Scale-dependence of lithological control on topography: Bedrock channel geometry and catchment morphometry in western Scotland

We propose that a scale-dependent topographic signature of erodibility arises due to fluvial and glacial erosion acting on different parts of the landscape at different times. For 14 catchments in western Scotland, we define three levels of substrate erodibility in order of decreasing resistance: quartzite rocks, nonquartzite rocks, and zones of fault-related fracture. Then, using digital topographic and planimetric data coupled with field measurements, we identify regression based scaling relationships between substrate erodibility and morphometric parameters at two spatial scales. Catchment-scale morphometry shows a weak to variable relationship with substrate metrics overall. Erodibility can be inferred from catchment steepness indices (i.e., channel steepness index and relief ratio), but the existence of multiple exceptions could confound a more general application of this approach. Nonetheless, major valley troughs trace fault zones and nonquartzite rocks, leaving much of the higher and steeper ground formed in quartzite. At the reach scale, bedrock channel slope is far more sensitive to substrate erodibility than is channel width. Quartzite outcrops steepen bedrock channels by a factor of 1.5–6.0, and in terms of unit stream power, channels increase their erosional capacity by a factor of 2.7–3.5. Yet only 4%–13% of this increase is due to channel narrowing. Based on a large data set of bedrock channel width (n = 5825) from four rivers, we find that width scales with drainage area (in m<sup>2</sup>) as W = 0.01A<sup>0.28</sup>. Our results are consistent with the view that width-area scaling is similar in all single-thread rivers subject to transport-limited conditions but that for increasingly sediment supply limited settings, erosional thresholds at the channel boundary are the key determinants of bedrock channel width

Foliations of Isonergy Surfaces and Singularities of Curves

It is well known that changes in the Liouville foliations of the isoenergy surfaces of an integrable system imply that the bifurcation set has singularities at the corresponding energy level. We formulate certain genericity assumptions for two degrees of freedom integrable systems and we prove the opposite statement: the essential critical points of the bifurcation set appear only if the Liouville foliations of the isoenergy surfaces change at the corresponding energy levels. Along the proof, we give full classification of the structure of the isoenergy surfaces near the critical set under our genericity assumptions and we give their complete list using Fomenko graphs. This may be viewed as a step towards completing the Smale program for relating the energy surfaces foliation structure to singularities of the momentum mappings for non-degenerate integrable two degrees of freedom systems.Comment: 30 pages, 19 figure

Gene expression and growth factor analysis in early nerve regeneration following segmental nerve defect reconstruction with a mesenchymal stromal cell-enhanced decellularized nerve all

Background: The purpose of this study was to evaluate the molecular mechanisms underlying nerve repair by a decellularized nerve allograft seeded with adiposederived mesenchymal stromal cells (MSCs) and compare it to the unseeded allograft and autograft nerve. Methods: Undifferentiated MSCs were seeded onto decellularized nerve allografts and used to reconstruct a 10 mm gap in a rat sciatic nerve model. Gene expression profiles of genes essential for nerve regeneration and immunohistochemical staining (IHC) for PGP9.5, NGF, RECA-1, and S100 were obtained 2 weeks postoperatively. Results: Semi-quantitative RT-PCR analysis showed that the angiogenic molecule VEGFA was significantly increased in seeded allografts, and transcription factor SOX2 was downregulated in seeded allografts. Seeded grafts showed a significant increase in immunohistochemical markers NGF and RECA-1, when compared with unseeded allografts. Conclusions: MSCs contributed to the secretion of trophic factors. A beneficial effect of the MSCs on angiogenesis was found when compared with the unseeded nerve allograft, but implanted MSCs did not show evidence of differentiation into Schwann cell-like cells

Tumori maligni delle ghiandole salivari della laringe: un'unica review istituzionale

I tumori a istotipo salivare della laringe sono molto rari, con pochi report in letteratura in merito al loro andamento clinico. Nel presente manoscritto discutiamo un'esperienza di 10 anni presso una singola struttura. Abbiamo condotto una review retrospettiva della casistica di un centro di oncologia della testa e del collo di terzo livello. I pazienti sono stati individuati mediante analisi di un database e sono stati revisionati da un Anatomo Patologo testa collo. I dati inerenti la clinica, le modalità di trattamento e gli esiti sono stati prelevati da archivi elettronici. Sono stati inclusi sei pazienti nello studio, con un range di età dai 44 ai 69 anni. Tutti e sei erano affetti da neoplasie maligne a istotipo salivare della laringe. Gli istotipi includevano: tre carcinomi adenoido-cistici (2 sopraglottico, 1 sottoglottico), un carcinoma mucoepidermoidale (sopraglottico), un carcinoma epiteliale-mioepiteliale (sopraglottico), e un adenocarcinoma (transglottico). Tutti sono stati sottoposti a trattamento chirurgico (2 chirurgie laser, 4 open) e 5 dei 6 pazienti sono stati successivamente sottoposti a terapia adjuvante (4 a radioterapia, 1 a radio-chemioterapia concomitante). Un paziente era fumatore; nessun paziente aveva storia di abuso di alcolici. A un follow-up con mediana di 4,5 anni nessuno dei pazienti ha presentato recidiva o metastasi locali o a distanza. I tumori a istotipo salivare della laringe si presentano solitamente in pazienti della seconda/terza età, e possono essere trattati con successo mediante approcci multimodali, con un ottimo controllo locoregionale di malattia

A New Approach to Assess the Gastrocnemius Muscle Volume in Rodents Using Ultrasound; Comparison with the Gastrocnemius Muscle Index

Introduction: The purpose of this study was to determine the reliability and validity of a new non-invasive ultrasound technique to measure gastrocnemius muscle atrophy after nerve denervation in an animal model. Methods: In sixteen rodents an eight mm sciatic nerve gap was created. In the following 8 weeks, each week, two rodents were euthanized and the gastrocnemius muscle was examined using two different ultrasound systems and two investigators. The standardized ultrasound measurement protocol consisted of identifying pre-defined anatomical landmarks: 1) the fibula, 2) the fibular nerve, and 3) the junction between the most distal point of the semitendinosus muscle and gastrocnemius muscle. Consequently, we measured the muscle thickness as the length of the line between the fibula and the junction between the two muscles, perpendicular to the fibular nerve. After the ultrasound recording, the muscle mass was determined. Results: A steep decline of muscle weight of 24% was observed after one week. In the following weeks, the weight further decreased and then remained stable from 6 weeks onwards, resulting in a maximal muscle weight decrease of 82%. The correlation coefficient was >0.96 between muscle diameter and weight using both ultrasound systems. The inter-rater reliability was excellent for both devices on the operated side (ICC of 0.99 for both ultrasound systems) and good for the non-operated site (ICC's: 0.84 & 0.89). The difference between the muscle mass ratio and the muscle thickness ratio was not more than 5% with two outliers of approximately 13%. Discussion: We have developed an innovative, highly reliable technique for quantifying muscle atrophy after nerve injury. This technique allows serial measurements in the same animal over time. This is a significant advantage compared to the conventional technique for quantifying muscle atrophy, which requires sacrificing the animal

Optical application and measurement of torque on microparticles of isotropic nonabsorbing material

We show how it is possible to controllably rotate or align microscopic particles of isotropic nonabsorbing material in a TEM00 Gaussian beam trap, with simultaneous measurement of the applied torque using purely optical means. This is a simple and general method of rotation, requiring only that the particle is elongated along one direction. Thus, this method can be used to rotate or align a wide range of naturally occurring particles. The ability to measure the applied torque enables the use of this method as a quantitative tool--the rotational equivalent of optical tweezers based force measurement. As well as being of particular value for the rotation of biological specimens, this method is also suitable for the development of optically-driven micromachines.Comment: 8 pages, 6 figure

Determinants of the maternal 25-hydroxyvitamin D response to vitamin D supplementation during pregnancy

Context: Current approaches to antenatal vitamin D supplementation do not account for interindividual differences in 25-hydroxyvitamin D (25(OH)D) response.Objective: We assessed which maternal and environmental characteristics were associated with 25(OH)D after supplementation with cholecalciferol.Design: Within-randomization-group analysis of participants in the Maternal Vitamin D Osteoporosis Study trial of vitamin D supplementation in pregnancy.Setting: Hospital antenatal clinics.Participants: A total of 829 pregnant women (422 placebo, 407 cholecalciferol). At 14 and 34 weeks of gestation, maternal anthropometry, health, and lifestyle were assessed and 25(OH)D measured. Compliance was determined using pill counts at 19 and 34 weeks.Interventions: 1000 IU/d of cholecalciferol or matched placebo from 14 weeks of gestation until delivery.Main Outcome Measure: 25(OH)D at 34 weeks, measured in a single batch (Diasorin Liaison).Results: 25(OH)D at 34 weeks of gestation was higher in the women randomized to vitamin D (mean [SD], 67.7 [21.3] nmol/L) compared with placebo (43.1 [22.5] nmol/L; P &lt; .001). In women randomized to cholecalciferol, higher pregnancy weight gain from 14 to 34 weeks of gestation (kg) (? = ?0.81 [95% confidence interval ?1.39, ?0.22]), lower compliance with study medication (%) (? = ?0.28 [?0.072, ?0.48]), lower early pregnancy 25(OH)D (nmol/L) (? = 0.28 [0.16, 0.40]), and delivery in the winter vs the summer (? = ?10.5 [?6.4, ?14.6]) were independently associated with lower 25(OH)D at 34 weeks of gestation.Conclusions: Women who gained more weight during pregnancy had lower 25(OH)D in early pregnancy and delivered in winter achieved a lower 25(OH)D in late pregnancy when supplemented with 1000 IU/d cholecalciferol. Future studies should aim to determine appropriate doses to enable consistent repletion of 25(OH)D during pregnancy.<br/

Muon spin relaxation studies of incommensurate magnetism and superconductivity in stage-4 La2_{2}CuO4.11_{4.11} and La1.88_{1.88}Sr0.12_{0.12}CuO4_{4}

This paper reports muon spin relaxation (MuSR) measurements of two single crystals of the title high-Tc cuprate systems where static incommensurate magnetism and superconductivity coexist. By zero-field MuSR measurements and subsequent analyses with simulations, we show that (1) the maximum ordered Cu moment size (0.36 Bohr magneton) and local spin structure are identical to those in prototypical stripe spin systems with the 1/8 hole concentration; (2) the static magnetism is confined to less than a half of the volume of the sample, and (3) regions with static magnetism form nano-scale islands with the size comparable to the in-plane superconducting coherence length. By transverse-field MuSR measurements, we show that Tc of these systems is related to the superfluid density, in the same way as observed in cuprate systems without static magnetism. We discuss a heuristic model involving percolation of these nanoscale islands with static magnetism as a possible picture to reconcile heterogeneity found by the present MuSR study and long-range spin correlations found by neutron scattering.Comment: 19 pages, 15 figures, submitted to Phys. Rev. B. E-mail: [email protected]

Does antenatal cholecalciferol supplementation affect the mode or timing of delivery? Post hoc analyses of the MAVIDOS randomized controlled trial

Background Observational studies relating maternal 25-hydroxyvitamin D status to timing and mode of delivery have reported inconsistent results. We assessed the effect of antenatal cholecalciferol supplementation on the incidence of preterm birth, delivery mode and post-partum haemorrhage (PPH). Methods MAVIDOS was a randomized, double-blind, placebo-controlled trial of 1000 IU/day cholecalciferol from 14 weeks’ gestation until delivery. Gestational age, mode of delivery [categorized as spontaneous vaginal delivery (SVD), instrumental (including forceps and vacuum extraction) or Caesarean section] and PPH (>500 ml estimated blood loss) were determined from medical records. Results A total of 965 women participated in the study until delivery. Gestation at birth and incidence of preterm birth (cholecalciferol 5.7%, placebo 4.5%, P = 0.43) were similar between the two treatment groups. SVD (versus instrumental or Caesarean delivery) was more likely in women randomized to cholecalciferol [Relative Risk (RR) 1.13, 95% confidence interval (CI) 1.02,1.25] due to lower instrumental (RR 0.68, 95%CI 0.51,0.91) but similar risk of Caesarean delivery (RR 0.94, 95%CI 0.74,1.19). PPH was less common in women randomized to cholecalciferol [32.1% compared with placebo (38.1%, P = 0.054) overall], but similar when stratified by delivery mode. Conclusions Antenatal cholecalciferol supplementation did not alter timing of birth or prevalence of preterm birth but demonstrated a possible effect on the likelihood of SVD

Pregnancy vitamin D supplementation and childhood bone mass at age 4 years : findings from the Maternal Vitamin D Osteoporosis Study (MAVIDOS) randomized controlled trial

In the Maternal Vitamin D Osteoporosis Study (MAVIDOS) randomized trial, vitamin D supplementation in pregnancy did not lead to greater neonatal bone mass across the trial as a whole, but, in a prespecified secondary analysis by season of birth, led to greater neonatal bone mass among winter-born babies. Demonstrating persistence of this effect into childhood would increase confidence in a long-term benefit of this intervention. We investigated whether antenatal vitamin D supplementation increases offspring bone mineralization in early childhood in a prespecified, single-center follow-up of a double-blinded, multicenter, randomized controlled clinical trial based in the UK (MAVIDOS). A total of 1123 women in early pregnancy with a baseline 25-hydroxyvitamin D level 25–100 nmol/L from three research centers (2008–2014) were randomized to 1000 IU/d cholecalciferol or matched placebo from 14 weeks of gestation to delivery. Offspring born at the Southampton, UK research center were assessed at age 4 years (2013–2018). Anthropometry and dual-energy X-ray absorptiometry (DXA) were performed (yielding whole body less head [WBLH] bone mineral content [BMC], areal bone mineral density [aBMD], bone area [BA], and body composition). Of 723 children, 564 (78.0%) children attended the 4-year visit, 452 of whom had a useable DXA. Maternal vitamin D supplementation led to greater WBLH aBMD in the children compared with placebo (mean [95% confidence interval {CI}]: supplemented group: 0.477 (95% CI, 0.472–0.481) g/cm2; placebo group: 0.470 (95% CI, 0.466–0.475) g/cm2, p = 0.048). Associations were consistent for BMC and lean mass, and in age- and sex-adjusted models. Effects were observed across the whole cohort irrespective of season of birth. Maternal-child interactions were observed, with a greater effect size among children with low milk intake and low levels of physical activity. Child weight, height, and body mass index (BMI) were similar by maternal randomization group. These findings suggest a sustained beneficial effect of maternal vitamin D supplementation in pregnancy on offspring aBMD at age 4 years, but will require replication in other trials