Essays on the economics of human capital and health

This thesis consists of three essays on the topic of early determinants of human capital and health. Chapter 2 explores the average effect of selective schooling, assigning pupils to different secondary schools by ability, on adult health, well-being and labour market outcomes, adding timely evidence to the debate on the reintroduction of selective schools in England. Selection bias is addressed by balancing pre-treatment characteristics, followed by OLS and IV regressions. Findings show that selective schooling does not affect most measures of long-term health and well-being. However, it affects educational aspirations and it raises adult wages for both high- and low-ability pupils, compared to a mixed-ability system. Chapter 3 analyses the effect of selective schooling on long-term human capital for the marginal admitted pupil, comparing attendance to an academic school to its vocational alternative. Identification relies on a fuzzy regression discontinuity design, using proxies of entry test scores for selective secondary schools in England. Discontinuities in school assignment are estimated directly from the data. For the marginal admitted student, selective school attendance positively affects educational attainment, but this effect is conditional on having a favourable background. Other adult labour market and health outcomes are not affected. Chapter 4 investigates the effect of birth order of children in the family on risky behaviours and non-cognitive skills in adolescence. The paper uses a mother fixed-effect strategy to account for the endogeneity of fertility decisions and data from a UK household panel. Having older siblings is linked to a higher probability of engaging in early drinking, drug use and skipping school, and to lower non-cognitive skills. The link is stronger for boys and higher socio-economic status families. Differences in parental investments and the influence of older siblings explain part of the observed birth order effects

NMR study of CyaY and YFHJ, two proteins involved in iron metabolism

From the Summary: In this thesis we apply Nuclear Magnetic Resonance to gain insights into the structures and functions of the two proteins CyaY and YFHJ. The overall material is organised in eight chapters, an introduction and a conclusion. Chapter 1: In this chapter the basis of Nuclear Magnetic Resonance are provided, with reference to its application to the study of biological macromolecules Chapter 2: This chapter describes the 2D and 3D NMR experiments that allow the assignment of a protein\u2019s spectra. Chapter 3: Here a short description of the bioinformatic tools and software packages available to extract information on macromolecules is provided. The material is organised following the proteins\u2019 level of structure it refers to: first there is a short description of the web databases and the programs that can be used to extract information from the primary sequence of a protein, then an elucidation of the programs useful to analyse the secondary structure and some details on the one applied in this study to calculate the 3D structure; finally, the available tools for structure comparison and refinement are reported. Chapter 4: This chapter summarises what is known about Friedreich\u2019s ataxia and frataxin. Chapter 5: Here the study of CyaY iron binding site by means of NMR is presented. In the first part of the chapter the problems and advantages of using paramagnetic probes in NMR are briefly discussed. Chapter 6: This chapter reviews the systems involved in iron-sulphur clusters\u2019 biosynthesis with particular attention to the proteins encoded by the bacterial Iron Sulphur Cluster operon. Chapter 7: An elucidation of the 3D structure determination process of the protein YFHJ is reported. In the first part circular dichroism and its application in biomolecular studies are discussed. Chapter 8: This chapter illustrates the functional characterisation of the protein YFHJ by means of NMR, mass spectrometry and fluorescence polarisation. The techniques used are elucidated in the initial paragraphs

Post‐budburst hand finishing of winter spur pruning can delay technological ripening without altering phenolic maturity of Merlot berries

Background and Aims Global warming can lead to technological ripening occurring in advance of phenolic maturity for red wine cultivars. This study evaluated the effect of post‐budburst winter pruning on the phenology, yield components, berry composition and phenolic maturity in Vitis vinifera L. cv. Merlot. Methods and Results Mechanically pre‐pruned vines followed up with hand pruning during winter (Control) were compared to vines that were mechanically pre‐pruned and followed up with hand pruning after budburst when distal buds developed shoots with either three unfolded leaves (DF3) or eight unfolded leaves (DF8). Late pruning delayed budburst, flowering and, to a lesser extent, veraison. The delays were greater for DF8 than DF3 treatments. Yield decreased by about 40 and 71% in DF3 and DF8 vines, respectively, while sugar accumulation and reduction of TA were delayed by both pruning treatments. The concentration of anthocyanin and tannin and of extractable anthocyanin and tannin (of skin and seeds analysed separately) were not influenced by the DF3 treatment while tannin concentration increased in DF8 berries. Conclusions Delaying hand pruning of mechanically pre‐pruned vines until after budburst of distal nodes can delay technological ripening without affecting the concentration of anthocyanin and tannin of berries. Yield, however, is substantially reduced. Significance of the Study We verified the feasibility of a cost‐effective technique that can be adopted to counteract the hastening of sugar accumulation and organic acid decline caused by global warming on valuable black grapes

Bioactive sphene-based ceramic coatings on cpTi substrates for dental implants: An in vitro study

Titanium implant surface modifications have been widely investigated to favor the process of osseointegration. The present work aimed to evaluate the effect of sphene (CaTiSiO5) biocoating, on titanium substrates, on the in vitro osteogenic differentiation of Human Adipose-Derived Stem Cells (hADSCs). Sphene bioceramic coatings were prepared using preceramic polymers and nano-sized active fillers and deposited by spray coating. Scanning Electron Microscopy (SEM) analysis, surface roughness measurements and X-ray diffraction analysis were performed. The chemical stability of the coatings in Tris-HCl solution was investigated. In vitro studies were performed by means of proliferation test of hADSCs seeded on coated and uncoated samples after 21 days. Methyl Thiazolyl-Tetrazolium (MTT) test and immunofluorescent staining with phalloidin confirmed the in vitro biocompatibility of both substrates. In vitro osteogenic differentiation of the cells was evaluated using Alizarin Red S staining and quantification assay and real-time PCR (Polymerase Chain Reaction). When hADSCs were cultured in the presence of Osteogenic Differentiation Medium, a significantly higher accumulation of calcium deposits onto the sphene-coated surfaces than on uncoated controls was detected. Osteogenic differentiation on both samples was confirmed by PCR. The proposed coating seems to be promising for dental and orthopedic implants, in terms of composition and deposition technology

Vine Physiology, Yield Parameters and Berry Composition of Sangiovese Grape under Two Different Canopy Shapes and Irrigation Regimes

Vitis vinifera L. adapts well to a scarce availability of water in the soil. However, in recent decades, the combination of thermal stress with prolonged water scarcity could have dramatic consequences on the vine’s physiological status. In this paper, we evaluated the effects of two canopy shapes and two irrigation regimes at veraison on vine physiology, yield parameters and grape composition through biochemical and molecular approaches. The water shortage strongly influenced the physiology of Sangiovese only when the stress was moderate to severe. Neither the water stress limited to veraison nor the canopy shape were able to influence the yield parameters and sugar content, and a strong induction of the expression of the genes involved in the biosynthesis of anthocyanins was recorded only in conditions of moderate-to-severe stress. This phenomenon led to an increase in the anthocyanin content in berry skins until the end of veraison. Conversely, no significant effects occurred in terms of biochemical and molecular performance after re-watering and at harvest. Though the shape of the canopy could play a role only under elevated temperature and prolonged drought, severe water stress can affect the vine physiology and berry ripening during the veraison stag

Phosphorylation of S776 and 14-3-3 Binding Modulate Ataxin-1 Interaction with Splicing Factors

Ataxin-1 (Atx1), a member of the polyglutamine (polyQ) expanded protein family, is responsible for spinocerebellar ataxia type 1. Requirements for developing the disease are polyQ expansion, nuclear localization and phosphorylation of S776. Using a combination of bioinformatics, cell and structural biology approaches, we have identified a UHM ligand motif (ULM), present in proteins associated with splicing, in the C-terminus of Atx1 and shown that Atx1 interacts with and influences the function of the splicing factor U2AF65 via this motif. ULM comprises S776 of Atx1 and overlaps with a nuclear localization signal and a 14-3-3 binding motif. We demonstrate that phosphorylation of S776 provides the molecular switch which discriminates between 14-3-3 and components of the spliceosome. We also show that an S776D Atx1 mutant previously designed to mimic phosphorylation is unsuitable for this aim because of the different chemical properties of the two groups. Our results indicate that Atx1 is part of a complex network of interactions with splicing factors and suggest that development of the pathology is the consequence of a competition of aggregation with native interactions. Studies of the interactions formed by non-expanded Atx1 thus provide valuable hints for understanding both the function of the non-pathologic protein and the causes of the disease