Competitive adsorption of multiple proteins to nanoparticles: the Vroman effect revisited

Proteins adsorbed from the blood plasma change nanoparticles inter- actions with the surrounding biological environment. In general, the ad- sorption of multiple proteins has a non-monotonic time dependence, that is, proteins adsorbed at first may slowly be replaced by others. This “Vro- man effect” leads to a highly dynamic protein corona on nanoparticles that profoundly influences the immune response of the body. Thus, the temporal evolution of the corona must be taken into account when consid- ering applications of nanocarriers in, e.g., nanomedicine or drug delivery. Up to now, the Vroman effect is explained solely in terms of diffusion: Smaller proteins which diffuse faster are adsorbed first while larger ones, having a stronger interaction with the surface, are preferred at equilib- rium. Here we use dynamic density functional theory (DDFT) including steric and electrostatic interactions to provide a full model for the tem- poral evolution of the protein corona. In particular, we demonstrate that proper consideration of all interactions leads to Vroman-like adsorption signatures in widely different scenarios. Moreover, consideration of ener- getic terms predicts both competitive as well as co-operative adsorption. In this way, DDFT provides a reacher picture of the evolution of the dynamic protein coron

Theory and simulation of DNA-coated colloids: a guide for rational design.

By exploiting the exquisite selectivity of DNA hybridization, DNA-coated colloids (DNACCs) can be made to self-assemble in a wide variety of structures. The beauty of this system stems largely from its exceptional versatility and from the fact that a proper choice of the grafted DNA sequences yields fine control over the colloidal interactions. Theory and simulations have an important role to play in the optimal design of self assembling DNACCs. At present, the powerful model-based design tools are not widely used, because the theoretical literature is fragmented and the connection between different theories is often not evident. In this Perspective, we aim to discuss the similarities and differences between the different models that have been described in the literature, their underlying assumptions, their strengths and their weaknesses. Using the tools described in the present Review, it should be possible to move towards a more rational design of novel self-assembling structures of DNACCs and, more generally, of systems where ligand-receptor are used to control interactions.This is the final version of the article. It first appeared from the Royal Society of Chemistry via http://dx.doi.org/10.1039/C5CP06981

Financial and Accounting Approaches in Lease Appraisal

The determination of the residual debt at a given date of a lease agreement, when it occurs the case of insolvency or continuous arrears (i.e. an early termination, before the maturity of the lease plan), is often regulated by the contract, which fixes penalties and some kind of impairment reimbursement. Both the lessor and the lessee are required to calculate separately for the amount of the outstanding debt and the sum of the impairment reimbursement and of the penalties. In this paper, the authors propose a model for a precise quantification of the residual debt, the damage impairment and the penalty shares based on three rates: the contractual rate, the implicit internal rate(s) of return and the market prime rate. This model is consistent with both finance and accounting perspectives. The developed methodology can also be proven capable to detect early any usury behavior, when it is given a threshold by the law or when it can be inferred from the market, therefore improving decision making and the forecasting of actual costs of the agreement

A survey on Italian compost dairy barns

Compost-bedded pack barns, generally known as compost dairy barns, are alternative housing systems for dairy cows. In these barns, the whole surface of the resting area is covered with a deep-bedded pack that is frequently stirred in order to incorporate fresh manure into the pack and to enhance the evaporation of water. Experiences with compost bedded pack barns for dairy cows are reported in literature from the USA, Israel, the Netherlands and Austria. The main advantages of these housing systems regard animal welfare and manure management. Since 2006, this housing system has been applied consistently in Italy. However, scientific knowledge about Italian compost barns is still lacking. This study aims at describing housing system, assessing producers’ satisfaction and measuring performance of dairy cows housed in compost bedded pack barns. Ten commercial dairy farms in northern Italy was involved in the study. All pens in each farm were surveyed to determine the surface of total available area, bedded area and pack depth. In order to investigate management practices, labor requirement, consumption of bedding materials and producers satisfaction, a questionnaire was submitted to each farm manager. The temperature of the bedded pack was measured in each farm during summer and winter. Moreover, data from Italian Breeder Association were collected for each herd over a period of one year (from September 2011 to September 2012). For the ten compost barns involved in the study the average total available area was 10.9 m2 per cow and the average pack area was 6.7 m2 per cow. The bedded pack was aerated 1.4 times per day. The most commonly used bedding material in these farms was dry sawdust. The consumption of bedding materials was 8.1 m3 per cow per year. A clear tendency to inverse correlation was found between the space per cow and the amount of bedding needed per cow (R2= 0.395; p-value=0.051). Operations related to pack management require 4.1 hours of labor per cow per year. Direct relationship was found between the bedded area space per cow and the annual labor required for pack management per cow (R2=0.505; p-value=0.048). Performance of cows housed in compost barns included in this study was encouraging and although some concerns about the cost of bedding, overall producers were satisfied with this housing system

A general theory of DNA-mediated and other valence-limited interactions

We present a general theory for predicting the interaction potentials between DNA-coated colloids, and more broadly, any particles that interact via valence-limited ligand-receptor binding. Our theory correctly incorporates the configurational and combinatorial entropic factors that play a key role in valence-limited interactions. By rigorously enforcing self-consistency, it achieves near-quantitative accuracy with respect to detailed Monte Carlo calculations. With suitable approximations and in particular geometries, our theory reduces to previous successful treatments, which are now united in a common and extensible framework. We expect our tools to be useful to other researchers investigating ligand-mediated interactions. A complete and well-documented Python implementation is freely available at http://github.com/patvarilly/DNACC .Comment: 18 pages, 10 figure

Mobile linkers on DNA-coated colloids: valency without patches.

Colloids coated with single-stranded DNA (ssDNA) can bind selectively to other colloids coated with complementary ssDNA. The fact that DNA-coated colloids (DNACCs) can bind to specific partners opens the prospect of making colloidal "molecules." However, in order to design DNACC-based molecules, we must be able to control the valency of the colloids, i.e., the number of partners to which a given DNACC can bind. One obvious, but not very simple approach is to decorate the colloidal surface with patches of single-stranded DNA that selectively bind those on other colloids. Here we propose a design principle that exploits many-body effects to control the valency of otherwise isotropic colloids. Using a combination of theory and simulation, we show that we can tune the valency of colloids coated with mobile ssDNA, simply by tuning the nonspecific repulsion between the particles. Our simulations show that the resulting effective interactions lead to low-valency colloids self-assembling in peculiar open structures, very different from those observed in DNACCs with immobile DNA linkers.This is the author's accepted manuscript. The final version is published by APS in Physical Review Letters (http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.113.128303)

GEOGRAFÍAS DEL DIÁLOGO Y PROCESOS TRADUCTIVOS EN CARMEN MARTÍN GAITE - GEOGRAFIE DEL DIALOGO E PROCESSI TRADUTTIVI IN CARMEN MARTÍN GAITE

ABSTRACT (IT) Questa tesi costituisce il primo studio sistematico delle traduzioni di Carmen Mart\uedn Gaite, e del ruolo cruciale che svolsero nella sua opera e nella sua vita. I principali obbiettivi di ricerca sono la definizione del significato della traduzione nella biografia intellettuale della scrittrice e, rovesciando la prospettiva, l\u2019influenza del suo approccio letterario nella pratica traduttiva e nello sviluppo di una teoria implicita della traduzione. Carmen Mart\uedn Gaite selezionava le opere da tradurre a partire dai propri interessi letterari ed esistenziali, e stabiliva innumerevoli connessioni dialogiche, avanti e indietro nel tempo, tra i testi e gli autori tradotti e la propria scrittura, attraverso annotazioni nei Cuadernos de todo, prologhi, note di traduzione, recensioni, citazioni e le pi\uf9 diverse declinazioni intertestuali della sua produzione narrativa. Nel tradurre, la scrittrice faceva ricorso alle proprie capacit\ue0 letterarie per mediare tra l\u2019autore del testo, i lettori intesi come imprescindibili \u2018interlocutori\u2019, e il traduttore stesso, di cui sottolineava il ruolo interpretativo. Inoltre, Carmen Mart\uedn Gaite sosteneva la necessita di un maggior riconoscimento del traduttore, considerato un \u201cdemiurgo della parola\u201d al pari dello scrittore, con il quale condivide l\u2019impegno e le responsabilit\ue0 etiche ed estetiche. L\u2019approccio traduttivo di Carmen Mart\uedn Gaite interpella le teorie della traduzione contemporanee da un punto di vista narrativo e comunicativo, ed \ue8 caratterizzato dall\u2019integrazione dei requisiti etici ed estetici, dettati da una pratica orientata al lettore, con la visibilit\ue0 intenzionale del traduttore, ottenuta mediante l\u2019uso creativo dei paratesti. La ricerca \ue8 iniziata con la raccolta di tutti i dati di pubblicazione delle traduzioni di Carmen Mart\uedn Gaite e dei rispettivi paratesti (in particolare, prologhi e note del traduttore). Una volta fissato l\u2019ordine cronologico di pubblicazione, il lavoro di ricerca ha affrontato lo studio delle molteplici relazioni tra ogni traduzione e le opere della scrittrice. Il risultato di questi due aspetti dell\u2019indagine \ue8 presentato nelle ventiquattro sezioni che descrivono le caratteristiche principali di ogni testo tradotto, i suoi collegamenti con le circostanze della vita e della riflessione letteraria di Carmen Mart\uedn Gaite, e la sua influenza a lungo termine sul lavoro e il pensiero della scrittrice. Dopo un capitolo iniziale le diverse sezioni sono raggruppate in capitoli che corrispondono a quattro diversi periodi individuati nel lavoro e nella vita dell\u2019autrice. Il secondo capitolo si snoda negli anni del silenzio narrativo tra Ritmo lento e Retah\uedlas. Il terzo copre la stagione creativa successiva alla pubblicazione di El cuarto de atr\ue1s. Il quarto, segnato dal lutto e dalla rigenerazione, si conclude con la pubblicazione di Caperucita en Manhattan. Il quinto, infine, comprende gli ultimi anni di Carmen Mart\uedn Gaite, interamente dedicati alla letteratura. L\u2019ultimo capitolo della tesi, che corrisponde alla terza tappa della ricerca, svolge le questioni di maggior rilievo emerse in particolare dall\u2019esame dalle sue traduzioni di tre opere di Natalia Ginzburg. La proposta di alcuni esempi della pratica traduttiva di Carmen Mart\uedn Gaite \ue8 posta in relazione dialogica con un breve testo sulla traduzione della stessa scrittrice, con i principali contributi teorici dei Translation Studies, e con le riflessioni sul tema di Jos\ue9 Ortega y Gasset e Octavio Paz.ABSTRACT (EN) The thesis is the first in-depth study of the translations of Carmen Mart\uedn Gaite, and takes as its premise the pivotal role of translation in her life and literature. The main research objective is an investigation of the importance of translation in the writer\u2019s intellectual biography, and, from another perspective, the impact of her literary approach on her practice, and implicit theory, of translation. Firstly, Carmen Mart\uedn Gaite determined which works to translate on the basis of her literary and existential concerns in a given moment. She established countless dialogical connections between the translated texts (and authors) and her own work, through entries in the Cuadernos de todo, prologues to the translated texts, translation notes, reviews, quotations, and frequent intertextual nuances in her own novels. Secondly, Carmen Mart\uedn Gaite drew on her literary skills to mediate between a text\u2019s author, its readers, highly regarded as \u2018interlocutors\u2019, and its translator, whom she saw as playing an interpretative role. Her translation strategies combined the deliberate visibility of the translator, obtained through a creative use of paratexts, with the aesthetic and communication values of a target-oriented practice, and questioned contemporary translation theories from a narrative and communicative point of view. At the same time, she called for the recognition of the translator as a \u2018demiurge of the word\u2019, equal to the writer in terms of his or her commitment to ethical and aesthetic responsibilities. The research commenced with an assessment of the publication data of Gaite\u2019s translations, and the collection of all related paratexts (in particular, prologues and translator\u2019s notes). Having established the chronological order of publication, the research continued with an investigation of the relationship between each translation and Mart\uedn Gaite\u2019s own works. The results of these two research phases are presented in twenty-four sections that describe the salient features and peculiarities of each translation text, the connections between that text and the circumstances of Mart\uedn Gaite\u2019s life and literary reflections past and present, and its long-term influence on her work and thought. After the first preliminary chapter, the sections are grouped according to four distinct periods in the life and works of the author. The second chapter deals with the \u2018narrative silence\u2019 between Ritmo lento and Retah\uedlas. The third covers the creative season from the publication of El cuarto de atr\ue1s to the death of Gaite\u2019s daughter. The fourth, a time of mourning and regeneration, concludes with the publication of Caperucita en Manhattan. Finally, the fifth chapter encompass the last years of Carmen Mart\uedn Gaite\u2019s life, entirely devoted to literature. The last chapter of the thesis, corresponding to the final part of the research, consists of a reflection on Mart\uedn Gaite\u2019s translation of three original works by the Italian author Natalia Ginzburg. The different sections address some general questions in the translation practice of Carmen Mart\uedn Gaite and elucidate the findings with commentary and examples, comparing a short text on translation by the author herself with the leading contemporary contributions to Translation Studies, and with the reflections of Ortega y Gasset and Octavio Paz on translation.ABSTRACT (ES) La tesis doctoral que aqu\ued se presenta constituye el primer estudio sistem\ue1tico sobre la labor traductora de Carmen Mart\uedn Gaite, y sobre el papel crucial de las traducciones en su vida y obra. Los principales objetivos de investigaci\uf3n son la definici\uf3n del significado de la actividad de traducci\uf3n en la biograf\ueda intelectual de la escritora y, desde una perspectiva opuesta, pero complementaria, la influencia de su planteamiento literario en su pr\ue1ctica traductora y en el desarrollo de una teor\ueda impl\uedcita de la traducci\uf3n. Carmen Mart\uedn Gaite seleccionaba entre los encargos de traducci\uf3n las obras que estimulaban sus intereses literarios y existenciales en un determinado momento, y establec\ueda innumerables conexiones dial\uf3gicas entre los textos, los autores traducidos y su propia obra, como testifican muchas entradas en los Cuadernos de todo, as\ued como los pr\uf3logos, notas, rese\uf1as y citas relativas a sus traducciones, adem\ue1s de las frecuentes reelaboraciones intertextuales presentes en su obra narrativa. En la labor traductora, la escritora se aprovechaba de su competencia literaria para mediar entre el autor del texto y los lectores, siempre muy valorados como imprescindibles \u201cinterlocutores\u201d, reservando para el traductor un papel interpretativo. Asimismo, sostuvo la necesidad de un mayor reconocimiento para los traductores, que consideraba \u201cdemiurgos de la palabra\u201d, tal como los escritores, con los cuales comparten el compromiso art\uedstico y la responsabilidad hacia el lector. En su labor traductora, que se contrasta en la tesis con las teor\uedas traductol\uf3gicas contempor\ue1neas, Carmen Mart\uedn Gaite integraba los requisitos \ue9ticos y est\ue9ticos dictados por una pr\ue1ctica orientada hacia el lector, con la visibilidad del traductor, obtenida intencionadamente mediante el uso creativo de los paratextos. En la primera etapa de la investigaci\uf3n se ha fijado el corpus completo y el orden cronol\uf3gico de publicaci\uf3n de todas las traducciones, recogiendo tambi\ue9n copia de todos los respectivos paratextos (en particular pr\uf3logos y notas de la traductora). Posteriormente, el trabajo se ha focalizado en la multitud de interrelaciones entre cada uno de los textos traducidos y la obra de la escritora. El resultado de estos dos aspectos de la investigaci\uf3n se presenta en los veinticuatro apartados que describen las caracter\uedsticas principales de cada texto, sus conexiones con las circunstancias de la vida y de la reflexi\uf3n literaria de Carmen Mart\uedn Gaite, y su influencia a largo plazo en el trabajo y el pensamiento de la escritora. Los diferentes apartados est\ue1n agrupados a lo largo de los cap\uedtulos que van del 2 al 5, que corresponden a los cuatro per\uedodos individuados en el recorrido art\uedstico y existencial de la escritora. El primero se desarrolla en los a\uf1os de silencio narrativo entre Ritmo Lento y Retah\uedlas. El segundo ocupa la fase creativa siguiente a la publicaci\uf3n de El cuarto de atr\ue1s. El tercero, marcado por el luto y la regeneraci\uf3n, concluye con la publicaci\uf3n de Caperucita en Manhattan, y el cuarto abarca los \ufaltimos a\uf1os de vida de Carmen Mart\uedn Gaite, dedicados \uedntegramente a la literatura. El sexto cap\uedtulo de la tesis, que corresponde a la tercera y \ufaltima etapa de la investigaci\uf3n, se centra en las cuestiones de mayor relieve traductol\uf3gico surgidas, en particular, del an\ue1lisis de las traducciones de tres obras de la autora italiana Natalia Ginzburg. En los diferentes apartados en los que est\ue1 dividido, se ponen en relaci\uf3n dial\uf3gica algunos ejemplos de la pr\ue1ctica traductora de Carmen Mart\uedn Gaite con un breve texto de la misma autora sobre la traducci\uf3n, con los principales planteamientos te\uf3ricos, y con las reflexiones sobre este tema de Octavio Paz y Jos\ue9 Ortega y Gasset