ENTREPRENEURSHIP EDUCATION: DO STUDENT-COMPANIES OFFER SUPERIOR VALUE?

An entrepreneurship course for academic students is expected to be a vital stimulus to promote entrepreneurship and the setup of creative new businesses. But do the students learn the right things? A comparison is made between the more classic “business plan” course and the setup of an actual student company.entrepreneurship, education, students

Entrepreneurship education : do student-companies offer superior value?

An entrepreneurship course for academic students is expected to be a vital stimulus to promote entrepreneurship and the setup of creative new businesses. But do the students learn the right things? A comparison is made between the more classic“ business plan” course and the setup of an actual student company

No more replicating portfolios : a simple convex combination to understand the risk-neutral valuation method for the multi-step binomial valuation of a call option

This paper covers the valuation, from beginning to implementation, of a European call option on a stock using the multi-step binomial model in a risk-neutral world. The aim is to introduce this model in a simple but rather unconventional way. The usual presentation of the risk-neutral valuation, see Hull (2009), among others, relies on replicating portfolios. For most practitioners, this technique looks rather mysterious. We present a new transparent analysis requiring no replicating portfolios. The new finding to understand why the risk-neutral pricing is consistent with investors being risk-averse is the notion of a convex combination

No more replicating portfolios : a simple convex combination to understand the risk-neutral valuation method for the multi-step binomial valuation of a call option

This paper covers the valuation, from beginning to implementation, of a European call option on a stock using the multi-step binomial model in a risk-neutral world. The aim is to introduce this model in a simple but rather unconventional way. The usual presentation of the risk-neutral valuation, see Hull (2009),among others, relies on replicating portfolios. For most practitioners, this technique looks rather mysterious. We present a new transparent analysis requiring no replicating portfolios. The new finding to understand why the risk-neutral pricing is consistent with investors being risk-averse is the notion of a convex combination.investments, stock, Black-Scholes, volatility

The thyroglobulin gene: structure and control of expression

info:eu-repo/semantics/publishe

Human High Temperature Requirement Serine Protease A1 (HTRA1) Degrades Tau Protein Aggregates

Protective proteases are key elements of protein quality control pathways that are up-regulated, for example, under various protein folding stresses. These proteases are employed to prevent the accumulation and aggregation of misfolded proteins that can impose severe damage to cells. The high temperature requirement A (HtrA) family of serine proteases has evolved to perform important aspects of ATP-independent protein quality control. So far, however, no HtrA protease is known that degrades protein aggregates. We show here that human HTRA1 degrades aggregated and fibrillar tau, a protein that is critically involved in various neurological disorders. Neuronal cells and patient brains accumulate less tau, neurofibrillary tangles, and neuritic plaques, respectively, when HTRA1 is expressed at elevated levels. Furthermore, HTRA1 mRNA and HTRA1 activity are up-regulated in response to elevated tau concentrations. These data suggest that HTRA1 is performing regulated proteolysis during protein quality control, the implications of which are discussed

Restricted location of PSEN2/γ-secretase determines substrate specificity and generates an intracellular Aβ pool

gamma-Secretases are a family of intramembrane-cleaving proteases involved in various signaling pathways and diseases, including Alzheimer's disease (AD). Cells co-express differing gamma-secretase complexes, including two homologous presenilins (PSENs). We examined the significance of this heterogeneity and identified a unique motif in PSEN2 that directs this gamma-secretase to late endosomes/lysosomes via a phosphorylation-dependent interaction with the AP-1 adaptor complex. Accordingly, PSEN2 selectively cleaves late endosomal/lysosomal localized substrates and generates the prominent pool of intracellular A beta that contains longer A beta; familial AD (FAD)-associated mutations in PSEN2 increased the levels of longer A beta further. Moreover, a subset of FAD mutants in PSEN1, normally more broadly distributed in the cell, phenocopies PSEN2 and shifts its localization to late endosomes/lysosomes. Thus, localization of gamma-secretases determines substrate specificity, while FAD-causing mutations strongly enhance accumulation of aggregation-prone A beta 42 in intracellular acidic compartments. The findings reveal potentially important roles for specific intracellular, localized reactions contributing to AD pathogenesis

A mutation affecting the sodium/proton exchanger, SLC9A6, causes mental retardation with tau deposition

We have studied a family with severe mental retardation characterized by the virtual absence of speech, autism spectrum disorder, epilepsy, late-onset ataxia, weakness and dystonia. Post-mortem examination of two males revealed widespread neuronal loss, with the most striking finding being neuronal and glial tau deposition in a pattern reminiscent of corticobasal degeneration. Electron microscopic examination of isolated tau filaments demonstrated paired helical filaments and ribbon-like structures. Biochemical studies of tau demonstrated a preponderance of 4R tau isoforms. The phenotype was linked to Xq26.3, and further analysis identified an in-frame 9 base pair deletion in the solute carrier family 9, isoform A6 (SLC9A6 gene), which encodes sodium/hydrogen exchanger-6 localized to endosomal vesicles. Sodium/hydrogen exchanger-6 is thought to participate in the targeting of intracellular vesicles and may be involved in recycling synaptic vesicles. The striking tau deposition in our subjects reveals a probable interaction between sodium/proton exchangers and cytoskeletal elements involved in vesicular transport, and raises the possibility that abnormalities of vesicular targeting may play an important role in more common disorders such as Alzheimer’s disease and autism spectrum disorders