2,701 research outputs found
A one-dimensional model with water-like anomalies and two phase transitions
We investigate a one-dimensional model that shows several properties of
water. The model combines the long-range attraction of the van der Waals model
with the nearest-neighbor interaction potential by Ben-Naim, which is a step
potential that includes a hard core and a potential well. Starting from the
analytical expression for the partition function, we determine numerically the
Gibbs energy and other thermodynamic quantities. The model shows two phase
transitions, which can be interpreted as the liquid-gas transition and a
transition between a high-density and a low-density liquid. At zero
temperature, the low-density liquid goes into the crystalline phase.
Furthermore, we find several anomalies that are considered characteristic for
water. We explore a wide range of pressure and temperature values and the
dependence of the results on the depth and width of the potential well
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Rivers in practice: clinicians' assessments of patients' decision-making capacity
Since the Rivers v. Katz decision in 1986, clinicians in New York State have been required to assess patient decision-making capacity before judicial review of petitions to administer involuntary medication. The authors examined 42 capacity assessments made by psychiatrists at a large state hospital in New York City. Although the capacity assessments were often incomplete and rarely addressed the treatment decision, most clinicians judged patients as lacking capacity to make treatment decisions. The findings suggest that psychiatrists may view capacity assessments as irrelevant because of the manifestly grave nature of patients' illnesses or may not differentiate the capacity assessment from the mental status examination. The capacity assessment may nonetheless be a useful tool because it encourages clinicians to discuss the proposed treatment with patients and to present information more effectively in court
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Outcome of Involuntary Medication in a State Hospital System
Objective: The purpose of the study was to examine the course of involuntarily administered medication in a state hospital population. Method: The authors retrospectively examined the records of all 51 involuntarily medicated patients in six state hospitals in New York City in a single calendar year. Clinical course was recorded for the period of involuntary medication and for 12 months thereafter. These patients were compared to 51 patients on the same wards who accepted medication. Results: Clinicians assessed involuntarily medicated patients as more dangerous to themselves or others and less delusional after treatment than the comparison patients. Long-acting intramuscular antipsychotics were prescribed more frequently for involuntarily medicated patients. No differences were observed in rates of discharge, outpatient cooperation, or rehospitalization. Half of the patients in both groups remained continuously institutionalized, and of those who left the hospital, only 30% of the involuntarily medicated group and 40% of the comparison group took medication as outpatients. Conclusions: For these chronically severely ill patients, involuntary medication did not appear to enhance insight or cooperation or result in rapid return to the community. Involuntary medication is often a necessary short-term, in-hospital management strategy, but it does not replace the need to develop comprehensive, long-term inpatient and community-based approaches to the management of treatment refusal
Suicide and suicide risk
Although recent years have seen large decreases in the overall global rate of suicide fatalities, this trend is not reflected everywhere. Suicide and suicidal behaviour continue to present key challenges for public policy and health services, with increasing suicide deaths in some countries such as the USA. The development of suicide risk is complex, involving contributions from biological (including genetics), psychological (such as certain personality traits), clinical (such as comorbid psychiatric illness), social and environmental factors. The involvement of multiple risk factors in conveying risk of suicide means that determining an individual’s risk of suicide is challenging. Improving risk assessment, for example, by using computer testing and genetic screening, is an area of ongoing research. Prevention is key to reduce the number of suicide deaths and prevention efforts include universal, selective and indicated interventions, although these interventions are often delivered in combination. These interventions, combined with psychological (such as cognitive behavioural therapy, caring contacts and safety planning) and pharmacological treatments (for example, clozapine and ketamine) along with coordinated social and public health initiatives, should continue to improve the management of individuals who are suicidal and decrease suicide-associated morbidity
The Lantern Vol. 15, No. 2, Spring 1947
• Midsummer Afternoon\u27s Dream • Lost Love • The Rocket • Speak Now--- • Unique Experience • The Exile • Chronology • Procrustean Dike • A Faeble • The Paris Story • Inspiration • Gently Spoken • On Shavinghttps://digitalcommons.ursinus.edu/lantern/1041/thumbnail.jp
The Quantity Theory of Money is Valid. The New Keynesians are Wrong!
We test the quantity theory of money (QTM) using a novel approach and a large new sample. We do not follow the usual approach of first differentiating the logarithm of the Cambridge equation to obtain an equation relating the growth rate of real GDP, the growth rate of money and inflation. These variables must then again be ‘integrated’ by averaging in order to obtain stable relationships. Instead we suggest a much simpler procedure for testing directly the stability of the coefficient of the Cambridge equation. For 125 countries and post-war data we find the coefficient to be surprisingly stable. We do not select for high inflation episodes as was done in most empirical studies; inflation rates do not even appear in our data set.
Much work supporting the QTM has been done by economic historians and at the University of Chicago by Milton Friedman and his associates. The QTM was a foundation stone of the monetarist revolution. Subsequently belief in it waned. The currently dominant New Keynesian School, implicitly or explicitly denies the validity of the QTM. We survey this history and argue that the QTM is valid and New Keynesians are wrong
Considering the role of cognitive control in expert performance
© 2014, Springer Science+Business Media Dordrecht. Dreyfus and Dreyfus’ (1986) influential phenomenological analysis of skill acquisition proposes that expert performance is guided by non-cognitive responses which are fast, effortless and apparently intuitive in nature. Although this model has been criticised (e.g., by Breivik Journal of Philosophy of Sport, 34, 116–134 2007, Journal of the Philosophy of Sport, 40, 85–106 2013; Eriksen 2010; Montero Inquiry:An interdisciplinary Journal of Philosophy, 53, 105–122 2010; Montero and Evans 2011) for over-emphasising the role that intuition plays in facilitating skilled performance, it does recognise that on occasions (e.g., when performance goes awry for some reason) a form of ‘detached deliberative rationality’ may be used by experts to improve their performance. However, Dreyfus and Dreyfus (1986) see no role for calculative problem solving or deliberation (i.e., drawing on rules or mental representations) when performance is going well. In the current paper, we draw on empirical evidence, insights from athletes, and phenomenological description to argue that ‘continuous improvement’ (i.e., the phenomenon whereby certain skilled performers appear to be capable of increasing their proficiency even though they are already experts; Toner and Moran 2014) among experts is mediated by cognitive (or executive) control in three distinct sporting situations (i.e., in training, during pre-performance routines, and while engaged in on-line skill execution). We conclude by arguing that Sutton et al. Journal of the British Society for Phenomenology, 42, 78–103 (2011) ‘applying intelligence to the reflexes’ (AIR) approach may help to elucidate the process by which expert performers achieve continuous improvement through analytical/mindful behaviour during training and competition
Validation of the SCID-hu Thy/Liv mouse model with four classes of licensed antiretrovirals.
BackgroundThe SCID-hu Thy/Liv mouse model of HIV-1 infection is a useful platform for the preclinical evaluation of antiviral efficacy in vivo. We performed this study to validate the model with representatives of all four classes of licensed antiretrovirals.Methodology/principal findingsEndpoint analyses for quantification of Thy/Liv implant viral load included ELISA for cell-associated p24, branched DNA assay for HIV-1 RNA, and detection of infected thymocytes by intracellular staining for Gag-p24. Antiviral protection from HIV-1-mediated thymocyte depletion was assessed by multicolor flow cytometric analysis of thymocyte subpopulations based on surface expression of CD3, CD4, and CD8. These mice can be productively infected with molecular clones of HIV-1 (e.g., the X4 clone NL4-3) as well as with primary R5 and R5X4 isolates. To determine whether results in this model are concordant with those found in humans, we performed direct comparisons of two drugs in the same class, each of which has known potency and dosing levels in humans. Here we show that second-generation antiretrovirals were, as expected, more potent than their first-generation predecessors: emtricitabine was more potent than lamivudine, efavirenz was more potent than nevirapine, and atazanavir was more potent than indinavir. After interspecies pharmacodynamic scaling, the dose ranges found to inhibit viral replication in the SCID-hu Thy/Liv mouse were similar to those used in humans. Moreover, HIV-1 replication in these mice was genetically stable; treatment of the mice with lamivudine did not result in the M184V substitution in reverse transcriptase, and the multidrug-resistant NY index case HIV-1 retained its drug-resistance substitutions.ConclusionGiven the fidelity of such comparisons, we conclude that this highly reproducible mouse model is likely to predict clinical antiviral efficacy in humans
Effects of Oral Butyrate on Blood Pressure in Patients with Hypertension:A Randomized, Placebo-Controlled Trial
BACKGROUND: The microbiota-derived short chain fatty acid butyrate has been shown to lower blood pressure (BP) in rodent studies. Nonetheless, the net effect of butyrate on hypertension in humans remains uncovered. In this study, for the first time, we aimed to determine the effect of oral butyrate on BP in patients with hypertension. METHODS: We performed a double-blind randomized placebo-controlled trial including 23 patients with hypertension. Antihypertensive medication was discontinued for the duration of the study with a washout period of 4 weeks before starting the intervention. Participants received daily oral capsules containing either sodium butyrate or placebo with an equivalent dosage of sodium chloride for 4 weeks. The primary outcome was daytime 24-hour systolic BP. Differences between groups over time were assessed using linear mixed models (group-by-time interaction). RESULTS: Study participants (59.0±3.7 years; 56.5% female) had an average baseline office systolic BP of 143.5±14.6 mm Hg and diastolic BP of 93.0±8.3 mm Hg. Daytime 24-hour systolic and diastolic BP significantly increased over the intervention period in the butyrate compared with the placebo group, with an increase of +9.63 (95% CI, 2.02-17.20) mm Hg in daytime 24-hour systolic BP and +5.08 (95% CI, 1.34-8.78) mm Hg in diastolic BP over 4 weeks. Butyrate levels significantly increased in plasma, but not in feces, upon butyrate intake, underscoring its absorption.CONCLUSIONS: Four-week treatment with oral butyrate increased daytime systolic and diastolic BP in subjects with hypertension. Our findings implicate that butyrate does not have beneficial effects on human hypertension, which warrants caution in future butyrate intervention studies. REGISTRATION: URL: https://onderzoekmetmensen.nl/; Unique identifier: NL8924.</p
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