This article presents an antiwindup propor- tional-integral (PI) controller, using a saturating integrator, for a single-input and single-output (SISO) stable nonlinear plant, whose steady-state ...input-output map is increasing. We prove that, under reasonable assumptions, there exists an upper bound on the controller gain such that for any constant reference input, the corresponding equilibrium point of the closed-loop system is exponentially stable, with a "large" region of attraction. When the state of the closed-loop system converges to this equilibrium point, then the tracking error tends to zero. The closed-loop stability analysis employs Lyapunov methods in the framework of the singular perturbations theory. Finally, we show that if the plant satisfies the asymptotic gain property, then the closed-loop system is globally asymptotically stable for any sufficiently small controller gain. The effectiveness of the proposed PI controller is proved by showing how it performs as part of the control algorithm of a synchronverter (a special type of dc to ac power converter).
This paper presents a novel anti-windup proportional–integral controller for stable multi-input multi-output nonlinear plants. We use tools from projected dynamical systems theory to force the ...integrator state to remain in a desired (compact and convex) region, such that the plant input steady-state values satisfy the operational constraints of the problem. Under suitable monotonicity assumptions on the plant steady-state input–output map, we use singular perturbation theory results to prove the existence of a sufficiently small controller gain ensuring closed-loop (local) exponential stability and reference tracking for a feasible set of constant references. We suggest a particular controller design, which embeds (when possible) the right inverse of the plant steady-state input–output map. The relevance of the proposed controller scheme is validated through an application in the power systems domain, namely, the output (active and reactive) power regulation for a grid-connected synchronverter.
Lam and Esfeld have argued that, within Bohmian mechanics, the wave function can be interpreted as a physical structure instantiated by the fundamental particles posited by the theory. Further, to ...characterize the nature of this structure, they appeal to the framework of Ontic Structural Realism (OSR), thereby proposing a structuralist interpretation of Bohmian mechanics. However, I shall point out that OSR denotes a family of distinct views, each of which maintains a different account about the relation between structures and objects, and entails a different kind of ontology. Thus, in this paper I will show how to articulate the structuralist approach to Bohmian Mechanics accordingly to the different standard versions of OSR, and I will evaluate these alternatives. Moreover, I will propose a novel and
sui generis
kind of structuralist interpretation of Bohmian Mechanics, based on the framework of metaphysical coherentism.
Spontaneous collapse theories of quantum mechanics turn the usual Schrödinger equation into a stochastic dynamical law. In particular, in this paper I will focus on the GRW theory. Two philosophical ...issues that can be raised about GRW concern (a) the
ontology
of the theory, in particular the nature of the wave function and its role within the theory, and (b) the interpretation of the
objective probabilities
involved in the dynamics of the theory. During the last years, it has been claimed that we can take advantage of dispositional properties in order to develop an ontology for GRW theory, and also in order to ground the objective probabilities which are postulated by it. However, in this paper I will argue that the dispositional interpretations which have been discussed in the literature so far are either flawed or—at best—incomplete. If we want to endorse a dispositional interpretation of GRW theory we thus need an extended account which specifies the precise nature of those properties and which makes also clear how they can correctly ground all the probabilities postulated by the theory. Thus, after having introduced several different kinds of probabilistic dispositions, I will try to fill the gap in the literature by proposing a novel and complete dispositional account of GRW, based on what I call
spontaneous weighted multi-track propensities.
I claim that such an account can satisfy both of our desiderata.
Abstract The past few decades have seen a marked change in the composition of commonly smoked cannabis. These changes primarily involve an increase of the psychoactive compound ∆9 ...-tetrahydrocannabinol (THC) and a decrease of the potentially therapeutic compound cannabidiol (CBD). This altered composition of cannabis may be linked to persistent neuroanatomic alterations typically seen in regular cannabis users. In this review, we summarize recent findings from human structural neuroimaging investigations. We examine whether neuroanatomic alterations are 1) consistently observed in samples of regular cannabis users, particularly in cannabinoid receptor–high areas, which are vulnerable to the effects of high circulating levels of THC, and 2) associated either with greater levels of cannabis use (e.g., higher dosage, longer duration, and earlier age of onset) or with distinct cannabinoid compounds (i.e., THC and CBD). Across the 31 studies selected for inclusion in this review, neuroanatomic alterations emerged across regions that are high in cannabinoid receptors (i.e., hippocampus, prefrontal cortex, amygdala, cerebellum). Greater dose and earlier age of onset were associated with these alterations. Preliminary evidence shows that THC exacerbates, whereas CBD protects from, such harmful effects. Methodologic differences in the quantification of levels of cannabis use prevent accurate assessment of cannabis exposure and direct comparison of findings across studies. Consequently, the field lacks large “consortium-style” data sets that can be used to develop reliable neurobiological models of cannabis-related harm, recovery, and protection. To move the field forward, we encourage a coordinated approach and suggest the urgent development of consensus-based guidelines to accurately and comprehensively quantify cannabis use and exposure in human studies.
The effectiveness of interventions to increase influenza vaccination uptake in people aged 60 years and older varies by country and participant characteristics. This review updates versions published ...in 2010 and 2014.
To assess access, provider, system, and societal interventions to increase the uptake of influenza vaccination in people aged 60 years and older in the community.
We searched CENTRAL, which includes the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE, Embase, CINAHL, and ERIC for this update, as well as WHO ICTRP and ClinicalTrials.gov for ongoing studies to 7 December 2017. We also searched the reference lists of included studies.
Randomised controlled trials (RCTs) and cluster-randomised trials of interventions to increase influenza vaccination in people aged 60 years or older in the community.
We used standard methodological procedures as specified by Cochrane.
We included three new RCTs for this update (total 61 RCTs; 1,055,337 participants). Trials involved people aged 60 years and older living in the community in high-income countries. Heterogeneity limited some meta-analyses. We assessed studies as at low risk of bias for randomisation (38%), allocation concealment (11%), blinding (44%), and selective reporting (100%). Half (51%) had missing data. We assessed the evidence as low-quality. We identified three levels of intervention intensity: low (e.g. postcards), medium (e.g. personalised phone calls), and high (e.g. home visits, facilitators).Increasing community demand (12 strategies, 41 trials, 53 study arms, 767,460 participants)One successful intervention that could be meta-analysed was client reminders or recalls by letter plus leaflet or postcard compared to reminder (odds ratio (OR) 1.11, 95% confidence interval (CI) 1.07 to 1.15; 3 studies; 64,200 participants). Successful interventions tested by single studies were patient outreach by retired teachers (OR 3.33, 95% CI 1.79 to 6.22); invitations by clinic receptionists (OR 2.72, 95% CI 1.55 to 4.76); nurses or pharmacists educating and nurses vaccinating patients (OR 152.95, 95% CI 9.39 to 2490.67); medical students counselling patients (OR 1.62, 95% CI 1.11 to 2.35); and multiple recall questionnaires (OR 1.13, 95% CI 1.03 to 1.24).Some interventions could not be meta-analysed due to significant heterogeneity: 17 studies tested simple reminders (11 with 95% CI entirely above unity); 16 tested personalised reminders (12 with 95% CI entirely above unity); two investigated customised compared to form letters (both 95% CI above unity); and four studies examined the impact of health risk appraisals (all had 95% CI above unity). One study of a lottery for free groceries was not effective.Enhancing vaccination access (6 strategies, 8 trials, 10 arms, 9353 participants)We meta-analysed results from two studies of home visits (OR 1.30, 95% CI 1.05 to 1.61) and two studies that tested free vaccine compared to patient payment for vaccine (OR 2.36, 95% CI 1.98 to 2.82). We were unable to conduct meta-analyses of two studies of home visits by nurses plus a physician care plan (both with 95% CI above unity) and two studies of free vaccine compared to no intervention (both with 95% CI above unity). One study of group visits (OR 27.2, 95% CI 1.60 to 463.3) was effective, and one study of home visits compared to safety interventions was not.Provider- or system-based interventions (11 strategies, 15 trials, 17 arms, 278,524 participants)One successful intervention that could be meta-analysed focused on payments to physicians (OR 2.22, 95% CI 1.77 to 2.77). Successful interventions tested by individual studies were: reminding physicians to vaccinate all patients (OR 2.47, 95% CI 1.53 to 3.99); posters in clinics presenting vaccination rates and encouraging competition between doctors (OR 2.03, 95% CI 1.86 to 2.22); and chart reviews and benchmarking to the rates achieved by the top 10% of physicians (OR 3.43, 95% CI 2.37 to 4.97).We were unable to meta-analyse four studies that looked at physician reminders (three studies with 95% CI above unity) and three studies of facilitator encouragement of vaccination (two studies with 95% CI above unity). Interventions that were not effective were: comparing letters on discharge from hospital to letters to general practitioners; posters plus postcards versus posters alone; educational reminders, academic detailing, and peer comparisons compared to mailed educational materials; educational outreach plus feedback to teams versus written feedback; and an intervention to increase staff vaccination rates.Interventions at the societal levelNo studies reported on societal-level interventions.Study funding sourcesStudies were funded by government health organisations (n = 33), foundations (n = 9), organisations that provided healthcare services in the studies (n = 3), and a pharmaceutical company offering free vaccines (n = 1). Fifteen studies did not report study funding sources.
We identified interventions that demonstrated significant positive effects of low (postcards), medium (personalised phone calls), and high (home visits, facilitators) intensity that increase community demand for vaccination, enhance access, and improve provider/system response. The overall GRADE assessment of the evidence was moderate quality. Conclusions are unchanged from the 2014 review.
Lo scritto analizza il ruolo del terzo settore e del volontariato nel contesto dell’amministrazione penitenziaria. A partire dalle origini, passando dal dibattito in assemblea costituente, si ...ripercorre l’evoluzione normativa che ha riconosciuto un sempre maggiore spazio all’intervento del volontariato che il terzo settore può inverare. Trattandosi di un momento di grande fermento normativo, alla luce di alcune recenti riforme, tra cui la c.d. Riforma Cartabia, lo scritto precisa rischi e potenzialità del terzo settore in un contesto peculiare quale quello volto ad accogliere – in termini simbolici e pratici – chi sia privato della libertà personale, collocandoli nel quadro costituzionale. Sono in particolare i principi di solidarietà, di pari dignità, il principio personalista e il finalismo rieducativo a deporre per un sempre maggiore spazio del terzo settore nel contesto penitenziario, ferma restando la necessità di marcare una distanza rispetto a ruoli e funzioni dell’amministrazione pubblica, anche al fine di evitare che risultino non visibili le vistose inefficienze nei servizi trattamentali.
The processing of rewards and losses are crucial to everyday functioning. Considerable interest has been attached to investigating the anticipation and outcome phases of reward and loss processing, ...but results to date have been inconsistent. It is unclear if anticipation and outcome of a reward or loss recruit similar or distinct brain regions. In particular, while the striatum has widely been found to be active when anticipating a reward, whether it activates in response to the anticipation of losses as well remains ambiguous. Furthermore, concerning the orbitofrontal/ventromedial prefrontal regions, activation is often observed during reward receipt. However, it is unclear if this area is active during reward anticipation as well. We ran an Activation Likelihood Estimation meta‐analysis of 50 fMRI studies, which used the Monetary Incentive Delay Task (MIDT), to identify which brain regions are implicated in the anticipation of rewards, anticipation of losses, and the receipt of reward. Anticipating rewards and losses recruits overlapping areas including the striatum, insula, amygdala and thalamus, suggesting that a generalised neural system initiates motivational processes independent of valence. The orbitofrontal/ventromedial prefrontal regions were recruited only during the reward outcome, likely representing the value of the reward received. Our findings help to clarify the neural substrates of the different phases of reward and loss processing, and advance neurobiological models of these processes.
Parkinson's disease (PD) is a progressive and chronic neurodegenerative disease of the central nervous system. Early treatment for PD is efficient; however, long-term systemic medication commonly ...leads to deleterious side-effects. Strategies that enable more selective drug delivery to the brain using smaller dosages, while crossing the complex brain-blood barrier (BBB), are highly desirable to ensure treatment efficacy and decrease/avoid unwanted outcomes. Our goal was to design and test the neurotherapeutic potential of a forefront nanoparticle-based technology composed of albumin/PLGA nanosystems loaded with dopamine (ALNP-DA) in 6-OHDA PD mice model. ALNP-DA effectively crossed the BBB, replenishing dopamine at the nigrostriatal pathway, resulting in significant motor symptom improvement when compared to Lesioned and L-DOPA groups. Notably, ALNP-DA (20 mg/animal dose) additionally up-regulated and restored motor coordination, balance, and sensorimotor performance to non-lesioned (Sham) animal level. Overall, ALNPs represent an innovative, non-invasive nano-therapeutical strategy for PD, considering its efficacy to circumvent the BBB and ultimately deliver the drug of interest to the brain.
To review population-based studies of the prevalence and incidence of epilepsy worldwide and use meta-analytic techniques to explore factors that may explain heterogeneity between estimates.
The ...Preferred Reporting Items for Systematic Reviews and Meta-Analyses standards were followed. We searched MEDLINE and EMBASE for articles published on the prevalence or incidence of epilepsy since 1985. Abstract, full-text review, and data abstraction were conducted in duplicate. Meta-analyses and meta-regressions were used to explore the association between prevalence or incidence, age group, sex, country level income, and study quality.
A total of 222 studies were included (197 on prevalence, 48 on incidence). The point prevalence of active epilepsy was 6.38 per 1,000 persons (95% confidence interval 95% CI 5.57-7.30), while the lifetime prevalence was 7.60 per 1,000 persons (95% CI 6.17-9.38). The annual cumulative incidence of epilepsy was 67.77 per 100,000 persons (95% CI 56.69-81.03) while the incidence rate was 61.44 per 100,000 person-years (95% CI 50.75-74.38). The prevalence of epilepsy did not differ by age group, sex, or study quality. The active annual period prevalence, lifetime prevalence, and incidence rate of epilepsy were higher in low to middle income countries. Epilepsies of unknown etiology and those with generalized seizures had the highest prevalence.
This study provides a comprehensive synthesis of the prevalence and incidence of epilepsy from published international studies and offers insight into factors that contribute to heterogeneity between estimates. Significant gaps (e.g., lack of incidence studies, stratification by age groups) were identified. Standardized reporting of future epidemiologic studies of epilepsy is needed.
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