pp-adic quotient sets

For $A \subseteq \mathbb{N}$, the question of when $R(A) = \{a/a' : a, a' \in A\}$ is dense in the positive real numbers $\mathbb{R}_+$ has been examined by many authors over the years. In contrast, the $p$-adic setting is largely unexplored. We investigate conditions under which $R(A)$ is dense in the $p$-adic numbers. Techniques from elementary, algebraic, and analytic number theory are employed in this endeavor. We also pose many open questions that should be of general interest.Comment: 24 page

Liposome Enhanced Detection of Amyloid Protein Aggregates.

Thioflavin-T is used to image amyloid aggregates because of the excellent turn-on fluorescence properties, but binding affinities are low. By mounting multiple dye units on the surface of a vesicle, the binding affinity for α-synuclein fibrils is increased by three orders of magnitude, and the optical response is increased. Cooperative interactions of the dye headgroup and lipid with the protein provide a general strategy for the construction of multivalent amyloid probes based on vesicles.Engineering and Physical Sciences Research Council (EP/R005397/1 and EP/P008224/1)

L’Amministrazione come “pretesa” nel processo di integrazione europea

Sommario: 1. Premessa; 2. Convergenze nei principi e differenze nei metodi; 3. L’integrazione degli ordinamenti mediante l’integrazione dei principi: il cittadino europeo e le sue pretese nei confronti dell’amministrazione; 4. Dai principi generali del diritto comunitario allo statuto giuridico del rapporto cittadino-amministrazione tra diritto interno e diritto comunitario

Promoting Industrial Cultural Heritage by Augmented Reality: Application and Assessment

Backgrund: Recent improvements of augmented reality technologies have boosted the design and the development of new solutions to support the user when visiting cultural sites. Each kind of multimedia information can be conveyed to the user in a new and intriguing way. On the other hand, a model to evaluate this kind of AR solutions for cultural heritage still misses. Objective: This paper aims to bridge the gap between applications and assessment by proposing a multivariate evaluation model and its application for an Android mobile augmented reality application designed to support the user during the visit of the historical industrial site of Carpano in Turin, Italy. This site is now a museum that keeps alive the memory of antique procedures and industrial machineries. Method: The proposed assessment model is based on a star like representation, which is often used to denote multivariate models; the length of each ray denotes the value of the corresponding variate. A three-level scale has been chosen for the proposed star-like representation: full length corresponds to the high-maximum level, medium length corresponds to the fair-average level and short length corresponds to the poor-null level. Results: The proposed AR application has been used by 13 people who, at the end of the experience, filled a questionnaire. Subjective feedbacks allowed us to evaluate the application usability. Moreover, the multivariate evaluation model has been applied to the AR application, thus outlining advantages and drawbacks. Conclusion: The presented multivariate evaluation model considers several different elements that can have an impact on the user experience; it also takes into account the coherence of the multimedia material used to augment the visit, as well as the impact of different thematic routes, is assessed

Lithium abundances in globular clusters

Lithium is created during the Big Bang nucleosynthesis and it is destroyed in stellar interiors at relatively low temperatures. However, it should be preserved in the stellar envelopes of unevolved stars and progressively diluted during mixing processes. In particular, after the first dredge-up along the RGB, lithium should be completely destroyed, but this is not what we observe today in globular clusters. This element allows to test stellar evolutionary models, as well as different types of polluters for second population stars in the multiple population scenarios. Due to the difficulty in the measurement of the small available lithium line, few GCs have been studied in details so far. Literature results are not homogeneous for what concerns type of stars, sample sizes, and chemical analysis methods. The Gaia-ESO survey allows us to study the largest sample of GCs stars (about 2000, both dwarfs and giants) for which the lithium has been analysed homogeneously

Opettajan yritysyhteistyöaktiivisuuden ja organisaation tuen merkitys yrittäjyyden opettamisessa

Tämän tutkimuksen tavoitteena on selvittää 1) miten opettajan oma yritysyhteistyöaktiivisuus ja 2) opettajan kokema organisaation tuki vaikuttavat yrittäjyydessä käytettävien opetusmenetelmien käyttöön. Lisäksi tavoitteena on selvittää, millainen merkitys opettajan aiemmalla yrittäjyystaustalla on. Tutkimuksen aineisto perustuu Opettajan yrittäjyysmittaristo -työkalulla kerättyyn dataan. Opettajan yrittäjyysmittaristo on verkkopohjainen itsearviointijärjestelmä, jonka avulla opettaja voi itsearvioida sekä kehittää toimintaansa yrittäjyyden edistäjänä. Itsearviointityökalu sisältää 72 kysymystä liittyen yrittäjyyden edistämisen eri osa-alueisiin. Dataa on kerätty tietokantaan vuosina 2014-2016. Tulokset osoittavat, että sekä yritysyhteistyöaktiivisuudella että opettajan kokemalla organisationaalisella tuella on vaikutusta siihen, kuinka aktiivisesti ja monipuolisesti opettaja hyödyntää erilaisia opetusmenetelmiä yrittäjyyden opettamisessa. Näistä vielä suurempi merkitys on opettajan omalla yritysyhteistyöaktiivisuudella. Tulokset osoittavat myös, että sekä yritysyhteistyöaktiivisuuden että opettajan kokeman organisaation tuen vaikutus opetusmenetelmien käyttöön on vielä suurempi niiden opettajien kohdalla, joilla itsellään on aiempaa kokemusta omasta yrittäjyydestä. Avainsanat: ammattikorkeakoulu, opettaja, yrittäjyyden edistäminen, yrittäjyys, mittaristo, yritysyhteisty

Toxicity, Physiological, and Ultrastructural Effects of Arsenic and Cadmium on the Extremophilic Microalga Chlamydomonas acidophila

The cytotoxicity of cadmium (Cd), arsenate (As(V)), and arsenite (As(III)) on a strain of Chlamydomonas acidophila, isolated from the Rio Tinto, an acidic environment containing high metal(l)oid concentrations, was analyzed. We used a broad array of methods to produce complementary information: cell viability and reactive oxygen species (ROS) generation measures, ultrastructural observations, transmission electron microscopy energy dispersive x-ray microanalysis (TEM–XEDS), and gene expression. This acidophilic microorganism was affected differently by the tested metal/metalloid: It showed high resistance to arsenic while Cd was the most toxic heavy metal, showing an LC50 = 1.94 µM. Arsenite was almost four-fold more toxic (LC50= 10.91 mM) than arsenate (LC50 = 41.63 mM). Assessment of ROS generation indicated that both arsenic oxidation states generate superoxide anions. Ultrastructural analysis of exposed cells revealed that stigma, chloroplast, nucleus, and mitochondria were the main toxicity targets. Intense vacuolization and accumulation of energy reserves (starch deposits and lipid droplets) were observed after treatments. Electron-dense intracellular nanoparticle-like formation appeared in two cellular locations: inside cytoplasmic vacuoles and entrapped into the capsule, around each cell. The chemical nature (Cd or As) of these intracellular deposits was confirmed by TEM–XEDS. Additionally, they also contained an unexpected high content in phosphorous, which might support an essential role of poly-phosphates in metal resistance