211 research outputs found
Implicit indefinite objects at the syntax-semantics-pragmatics interface: a probabilistic model of acceptability judgments
Optionally transitive verbs, whose Patient participant is semantically obligatory but
syntactically optional (e.g., to eat, to drink, to write), deviate from the transitive prototype
defined by Hopper and Thompson (1980). Following Fillmore (1986), unexpressed objects
may be either indefinite (referring to prototypical Patients of a verb, whose actual entity
is unknown or irrelevant) or definite (with a referent available in the immediate intra- or
extra-linguistic context). This thesis centered on indefinite null objects, which the literature
argues to be a gradient, non-categorical phenomenon possible with virtually any transitive
verb (in different degrees depending on the verb semantics), favored or hindered by several
semantic, aspectual, pragmatic, and discourse factors. In particular, the probabilistic
model of the grammaticality of indefinite null objects hereby discussed takes into account
a continuous factor (semantic selectivity, as a proxy to object recoverability) and four
binary factors (telicity, perfectivity, iterativity, and manner specification).
This work was inspired by Medina (2007), who modeled the effect of three predictors
(semantic selectivity, telicity, and perfectivity) on the grammaticality of indefinite null
objects (as gauged via Likert-scale acceptability judgments elicited from native speakers
of English) within the framework of Stochastic Optimality Theory. In her variant of the
framework, the constraints get floating rankings based on the input verb’s semantic
selectivity, which she modeled via the Selectional Preference Strength measure by Resnik
(1993, 1996). I expanded Medina’s model by modeling implicit indefinite objects in two
languages (English and Italian), by using three different measures of semantic selectivity
(Resnik’s SPS; Behavioral PISA, inspired by Medina’s Object Similarity measure; and
Computational PISA, a novel similarity-based measure by Cappelli and Lenci (2020)
based on distributional semantics), and by adding iterativity and manner specification as
new predictors in the model.
Both the English and the Italian five-predictor models based on Behavioral PISA explain
almost half of the variance in the data, improving on the Medina-like three-predictor
models based on Resnik’s SPS. Moreover, they have a comparable range of predicted
object-dropping probabilities (30-100% in English, 30-90% in Italian), and the predictors
perform consistently with theoretical literature on object drop. Indeed, in both models,
atelic imperfective iterative manner-specified inputs are the most likely to drop their
object (between 80% and 90%), while telic perfective non-iterative manner-unspecified
inputs are the least likely (between 30% and 40%). The constraint re-ranking probabilities
are always directly proportional to semantic selectivity, with the exception of Telic End
in Italian. Both models show a main effect of telicity, but the second most relevant factor
in the model is perfectivity in English and manner specification in Italian
PISA: A measure of Preference In Selection of Arguments to model verb argument recoverability
Our paper offers a computational model ofthe semantic recoverability of verb arguments,tested in particular on direct objects and In-struments. Our fully distributional model isintended to improve on older taxonomy-basedmodels, which require a lexicon in addition tothe training corpus. We computed the selec-tional preferences of 99 transitive verbs and173 Instrument verbs as the mean value of thepairwise cosine similarity between their argu-ments (a weighted mean between all the argu-ments, or an unweighted mean with the top-mostkarguments).Results show that ourmodel can predict the recoverability of objectsand Instruments, providing a similar result tothat of taxonomy-based models but at a muchcheaper computational cost
Argomenti e aggiunti nei verbi italiani: uno studio computazionale
La classificazione dei complementi di un verbo1 relativamente alla loro argumenthood2 non sempre è agevole: se infatti è possibile definire senza dubbio “argomenti” i dipendenti obbligatori di un verbo e, viceversa, “aggiunti” quelli opzionali, la situazione cambia in casi meno chiari di questi. Il presente elaborato intende offrire al lettore una rassegna esauriente sullo stato dell’arte in materia di argomenti e aggiunti, partendo dalle definizioni fino ad arrivare ai modelli teorici e alle strategie computazionali elaborate per operare il discrimine nella pratica; si discuteranno nel dettaglio i criteri ideati per diagnosticare l’argumenthood e i metodi computazionali coi quali tali strumenti acquistano correlati distribuzionali e statistici applicabili a studi dati empirici o estratti da corpora
On the nature of charge-transfer excitations for molecules in aqueous solution: a polarizable QM/MM study
We illustrate the effect of solvation on the nature of electronic excitations of organic molecules which possess excited states of charge-transfer character. The analysis is carried out using both a continuum model and a polarizable QM/MM method that treats the solvent atomistically and embeds each atom in the solvent with a fluctuating charge which responds to the solute quantum-mechanical electrostatic potential in a self-consistent manner. We also show how solvation dynamics can influence the nature of the excited state of molecular systems. The application of the model to aqueous solutions of doxorubicin and a substituted polythiophene derivative shows that the solvent significantly affects the nature the excited states, which results in an enhanced or reduced charge-transfer character as measured using two of the most popular indices for evaluating the distance traveled by the electrons upon excitation
Rethinking Chronic Kidney Disease in the Aging Population
The process of aging population will inevitably increase age-related comorbidities including chronic kidney disease (CKD). In light of this demographic transition, the lack of an age-adjusted CKD classification may enormously increase the number of new diagnoses of CKD in old subjects with an indolent decline in kidney function. Overdiagnosis of CKD will inevitably lead to important clinical consequences and pronounced negative effects on the health-related quality of life of these patients. Based on these data, an appropriate workup for the diagnosis of CKD is critical in reducing the burden of CKD worldwide. Optimal management of CKD should be based on prevention and reduction of risk factors associated with kidney injury. Once the diagnosis of CKD has been made, an appropriate staging of kidney disease and timely prescriptions of promising nephroprotective drugs (e.g., RAAS, SGLT-2 inhibitors, finerenone) appear crucial to slow down the progression toward end-stage kidney disease (ESKD). The management of elderly, comorbid and frail patients also opens new questions on the appropriate renal replacement therapy for this subset of the population. The non-dialytic management of CKD in old subjects with short life expectancy features as a valid option in patient-centered care programs. Considering the multiple implications of CKD for global public health, this review examines the prevalence, diagnosis and principles of treatment of kidney disease in the aging population
GREASE II. A phase II randomized, 12-month, parallel-group, superiority study to evaluate the efficacy of a Modified Atkins Diet in Autosomal Dominant Polycystic Kidney Disease patients
Introduction
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a condition that causes progressive renal function decline. Preclinical data suggest the presence of a profound metabolic derangement in ADPKD. Cystic cells shift their energy metabolism from oxidative phosphorylation to aerobic glycolysis, show inhibition of fatty acid oxidation and become glutamine and arginine dependent. Recent preclinical experiences have suggested beneficial effect in terms of reduction of cystic size, interstitial fibrosis and disease progression, targeting these deregulated metabolic pathways by ketosis induction. The dietetic approach to ADPKD, because of low cost and absence of toxicity, represents an interesting therapeutic strategy.
Methods and analysis
The protocol describes a phase II clinical trial that will evaluate the effect on Total Kidney Volume, safety and tolerability of a ketogenic diet in a selected ADPKD population. The trial will have, as secondary objective, the evaluation of the ability of the ketogenic diet to slow down the renal function decline. This will be a 12-month randomized, parallel group, two arm, superiority trial with 1:1 allocation to evaluate the efficacy of a Modified Atkins Diet protocol compared to a balanced normocaloric diet on 90 ADPKD patients.
Dissemination
The study results will be released to the patients and the medical community
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