A simple limit for slope instability

Ross and Thomas have shown that subschemes can K-destabilise polarised varieties, yielding a notion known as slope (in)stability for varieties. Here we describe a special situation in which slope instability for varieties (for example of general type) corresponds to a slope instability type condition for certain bundles, making the computations almost trivial.Comment: 11 page

Overcoming the fear: an autoethnographic narrative of running with epilepsy

Through a phenomenological approach, this article explores the identity conflict that arose within a female runner after diagnosis with epilepsy. Utilising a three month autoethnography to track her experiences of returning to running, the first author narrates the effect of epilepsy on her identity formation. Providing a voice that is absent from a research area dominated by statistics, the reader is asked to involve him/herself in the world of this athlete and in turn embrace the use of narratives as a valuable coping mechanism for those with chronic disorders

Can water management reduce NH3 emissions from urea application in rice paddies?

Ammonia (NH3) is one of the main reactive components of the troposphere and its deposition is a major environmental treat. Rice fields are particular sensitive environment in which NH3 volatilisation can be mitigated according to water management, increasing the effectiveness of the fertiliser and reducing environmental issues. Urea is the most common N-fertiliser used for rice production and the determination of NH3 emissions from different water managements is still far from clear. A two year experiment was designed to quantify NH3 releases from two urea applications, at tillering and at panicle initiation, and with three different treatment of water managements: (i) \u201cDRY\u201d, with fertilisations on dry soil; (ii) \u201cFLD-D\u201d - water seeding continuous flooding - with fertilisations on temporally dried soil surface; (iii) \u201cFLD-W\u201d - water seeding continuous flooding - with fertilisation into standing water. Measurements were carried out on three contiguous plots, one treatment each, of 2650m2 (5053m) in Castello D\u2019Agogna (Italy) during 2015 and 2016; fertilisations provided 70+50 kg N/ha for DRY and 60+40 kg N/ha for FDL-D and FLD-W. NH3 emissions were quantified by means of concentration-based inverse dispersion modelling, applied to a multi-plot design. This low-cost method allows measuring gas concentrations above the soil surface by using integrationtime passive samplers, placed in each plot at 1 m height above soil surface (or crop canopy) and replaced each 6h during the more turbulent daylight hours and kept for 12h during calm night-time. Two additional measurement points assessed background concentration near the plots. Surface to atmosphere exchanges were quantified with the Eulerian short-range dispersion model FIDES-3D (INRA, France) in a multi-plot configuration, in order to tackle with the mutual advection from the three nearby and different sources. Flux were corrected for low turbulence and near-neutrality conditions (u <0.05m/s), jLj < 2m); 15%of the data. Water management played a key-role to control NH3 emissions both at tillering and panicle initiation. When fertilisations occurred directly on soil surface, residual surface humidity was determinant, in fact with soil water contents lower than the field capacity (DRY), the emissions were the lowest, start to emitting when the paddy was re-wetted, and following the circadian trend of air temperatures. Conversely, when the soil surface was not completely dried (i.e. drying time too short; FLD-D) and the soil water content resulting above the field capacity, an unique, intense and rapid NH3 emission peak was produced in the first 24h from the fertiliser distribution. This effect was probably due to the rapid hydrolysis combined to the urease activity on soil surface. When the fertilisation occurred directly into the water (FLD-W), emissions were prolonged over time and assumed intermediate intensities with no main peaks. Water management after the fertilisation spreading affected secondarily the emissions, outlining discrete emission phenomena only when the paddies were dried out. NH3 emissions at tillering and at panicle differentiation were, respectively DRY: 3.2 +/- 0:6% - 5:9%; FLD-D : 17:8 +/- 4:1% - 21:0 +/- 4:2%; FLD-W : 14:5 +/- 4:9% - 17:5 +/- 8:3%

N-acetylcysteine treatment ameliorates the skeletal phenotype of a mouse model of diastrophic dysplasia.

Diastrophic dysplasia (DTD) is a recessive chondrodysplasia caused by mutations in SLC26A2, a cell membrane sulfate-chloride antiporter. Sulfate uptake impairment results in low cytosolic sulfate, leading to cartilage proteoglycan (PG) undersulfation. In this work, we used the dtd mouse model to study the role of N-acetyl-l-cysteine (NAC), a well-known drug with antioxidant properties, as an intracellular sulfate source for macromolecular sulfation. Because of the important pre-natal phase of skeletal development and growth, we administered 30 g/l NAC in the drinking water to pregnant mice to explore a possible transplacental effect on the fetuses. When cartilage PG sulfation was evaluated by high-performance liquid chromatography disaccharide analysis in dtd newborn mice, a marked increase in PG sulfation was observed in newborns from NAC-treated pregnancies when compared with the placebo group. Morphometric studies of the femur, tibia and ilium after skeletal staining with alcian blue and alizarin red indicated a partial rescue of abnormal bone morphology in dtd newborns from treated females, compared with pups from untreated females. The beneficial effect of increased macromolecular sulfation was confirmed by chondrocyte proliferation studies in cryosections of the tibial epiphysis by proliferating cell nuclear antigen immunohistochemistry: the percentage of proliferating cells, significantly reduced in the placebo group, reached normal values in dtd newborns from NAC-treated females. In conclusion, NAC is a useful source of sulfate for macromolecular sulfation in vivo when extracellular sulfate supply is reduced, confirming the potential of therapeutic approaches with thiol compounds to improve skeletal deformity and short stature in human DTD and related disorders

Collagen fibril structure is affected by collagen concentration and decorin.

Collagen fibrils were obtained in vitro by aggregation from acid-soluble type I collagen at different initial concentrations and with the addition of decorin core or intact decorin. All specimens were observed by scanning electron microscopy and atomic force microscopy. In line with the findings of other authors, lacking decorin, collagen fibrils undergo an extensive lateral association leading to the formation of a continuous three-dimensional network. The addition of intact decorin or decorin core was equally effective in preventing lateral fusion and restoring the normal fibril appearance. In addition, the fibril diameter was clearly dependent on the initial collagen concentration but not on the presence/absence of proteoglycans. An unusual fibril structure was observed as a result of a very low initial collagen concentration, leading to the formation of huge, irregular superfibrils apparently formed by the lateral coalescence of lesser fibrils, and with a distinctive coil-structured surface. Spots of incomplete fibrillogenesis were occasionally found, where all fibrils appeared made of individual, interwined subfibrils, confirming the presence of a hierarchical association mechanism