Thermostatistical description of small systems in nonequilibrium conditions: Energy conversion and harvesting

Hysteresis cycles are very important features of energy conversion and harvesting devices, such as batteries. The efficiency of these may be strongly affected by the physical size of the system. Here, we show that in systems which are small enough, the existence of physical boundaries which produce nonhomogeneities of the interaction potential gives rise to inflections and barriers in the associated free energy. This in turn brings on irreversible processes which can be triggered under suitable external conditions imposed by a heat bath. As an example, by controlling the temperature, the state of a small system may be impelled to oscillate between two different structural configurations or aggregation states avoiding equilibrium coexistence and therefore dissipating energy. This cyclical behavior associated with a hysteresis cycle may be prototypical of energy conversion, storage, or generating nanodevices, as exemplified by Li-ion insertion batteries.

Effectiveness of psychotropic medications in the maintenance phase of bipolar disorder:a meta-analysis of randomized controlled trials

The purpose of this meta-analysis was to examine the efficacy of maintenance treatments for bipolar disorder. Placebo-controlled or active comparator bipolar maintenance clinical trials of ≥6 months' duration with at least 15 patients/treatment group were identified using Medline, EMBASE, clinicaltrials.gov, and Cochrane databases (1993 to July 2010). The main outcome measure was relative risk for relapse for patients in remission. Twenty trials (5,364 patients) were identified. Overall, lithium and quetiapine were the most studied agents (eight and five trials, respectively). The majority of studies included patients who had previously responded to treatment for an acute episode. All interventions, with the exception of perphenazine+mood stabilizer, showed a relative risk for manic/mixed or depressive relapse below 1.0, although there was variation in the statistical significance of the findings vs. placebo. No monotherapy was associated with a significantly reduced risk for both manic/mixed and depressed relapse. Of the combination treatments, only quetiapine+lithium/divalproex, was associated with a significantly reduced risk vs. comparator (placebo+lithium/valproate) for relapse at both the manic/mixed and depressed poles of bipolar illness. Limitations for the analysis include differences in study durations and definitions of relapse. In conclusion, available maintenance therapies show considerable variation in efficacy. The efficacy of lithium and divalproex has been confirmed, but newer therapies, such as a number of atypical antipsychotics were also shown to be effective in bipolar disorder. Efficacy of all maintenance interventions needs to be balanced against the safety and tolerability profiles of individual agents.

Efficacy and safety of aripiprazole in the treatment of bipolar disorder: a systematic review.

Abstract BACKGROUND: The current article is a systematic review concerning the efficacy and safety of aripiprazole in the treatment of bipolar disorder. METHODS: A systematic Medline and repositories search concerning the usefulness of aripiprazole in bipolar disorder was performed, with the combination of the words 'aripiprazole' and 'bipolar'. RESULTS: The search returned 184 articles and was last updated on 15 April 2009. An additional search included repositories of clinical trials and previous systematic reviews specifically in order to trace unpublished trials. There were seven placebo-controlled randomised controlled trials (RCTs), six with comparator studies and one with add-on studies. They assessed the usefulness of aripiprazole in acute mania, acute bipolar depression and during the maintenance phase in comparison to placebo, lithium or haloperidol. CONCLUSION: Aripiprazole appears effective for the treatment and prophylaxis against mania. The data on bipolar depression are so far negative, however there is a need for further study at lower dosages. The most frequent adverse effects are extrapyramidal signs and symptoms, especially akathisia, without any significant weight gain, hyperprolactinaemia or laboratory test changes.

Jäänhoitokoneen voimansiirron kehittäminen

Diplomityön tavoitteena oli tutkia jäänhoitokoneen nykyisen voimanlähteen mahdollista korvaamista eri tekniikkaan perustuvilla voimanlähteillä. Teoriaosassa tutustutaan jäänhoidon historiaan eli mistä tarve jäänhoitokoneiden suunnitteluun ja valmistukseen on syntynyt. Samoin esitellään jäähoidon koko prosessi ja eri käyttövoimanlähteet mitä maailmalla jäänhoitokoneissa on käytössä. Käytännön osuus keskittyy aluksi esittelemään jäänhoitokoneen nykyisen toimintaperiaatteen, siinä käytetyt komponentit sekä kartoittaa koko järjestelmän heikkoudet ja vahvuudet. Osuudessa selvitetään myös kahden nykyisestä poikkeavien voimanlähteiden toimintaperiaatteet sekä niiden mahdollisuudesta korvata jäänhoitokoneen nykyinen järjestelmä. Näiden osalta selvitetään myös vaihtoehtoisten tekniikoiden heikkoudet ja vahvuudet. Työn tuloksena selvisi, että uudet korvaavat voimanlähteet ovat vielä kehitysvaiheessa eikä siis vielä tarpeeksi valmiita, suorituskykyisiä tai saasteettomia korvaamaan nykyistä 0-päästöistä sähkömoottorijärjestelmää. Sen sijaan kehitysehdotuksena syntyi idea nykyisen järjestelmän optimoimisesta paremman hyötysuhteen ja sitä mukaa akkujen eliniän parantamiseksi.

Antipsychotic polypharmacy in a regional health service: a population-based study

Background To analyse the extent and profile of outpatient regular dispensation of antipsychotics, both in combination and monotherapy, in the Barcelona Health Region (Spain), focusing on the use of clozapine and long-acting injections (LAI). Methods Antipsychotic drugs dispensed for people older than 18 and processed by the Catalan Health Service during 2007 were retrospectively reviewed. First and second generation antipsychotic drugs (FGA and SGA) from the Anatomical Therapeutic Chemical classification (ATC) code N05A (except lithium) were included. A patient selection algorithm was designed to identify prescriptions regularly dispensed. Variables included were age, gender, antipsychotic type, route of administration and number of packages dispensed. Results A total of 117,811 patients were given any antipsychotic, of whom 71,004 regularly received such drugs. Among the latter, 9,855 (13.9%) corresponded to an antipsychotic combination, 47,386 (66.7%) to monotherapy and 13,763 (19.4%) to unspecified combinations. Of the patients given antipsychotics in association, 58% were men. Olanzapine (37.1%) and oral risperidone (36.4%) were the most common dispensations. Analysis of the patients dispensed two antipsychotics (57.8%) revealed 198 different combinations, the most frequent being the association of FGA and SGA (62.0%). Clozapine was dispensed to 2.3% of patients. Of those who were receiving antipsychotics in combination, 6.6% were given clozapine, being clozapine plus amisulpride the most frequent association (22.8%). A total of 3.800 patients (5.4%) were given LAI antipsychotics, and 2.662 of these (70.1%) were in combination. Risperidone was the most widely used LAI. Conclusions The scant evidence available regarding the efficacy of combining different antipsychotics contrasts with the high number and variety of combinations prescribed to outpatients, as well as with the limited use of clozapine. Background To analyse the extent and profile of outpatient regular dispensation of antipsychotics, both in combination and monotherapy, in the Barcelona Health Region (Spain), focusing on the use of clozapine and long-acting injections (LAI). Methods Antipsychotic drugs dispensed for people older than 18 and processed by the Catalan Health Service during 2007 were retrospectively reviewed. First and second generation antipsychotic drugs (FGA and SGA) from the Anatomical Therapeutic Chemical classification (ATC) code N05A (except lithium) were included. A patient selection algorithm was designed to identify prescriptions regularly dispensed. Variables included were age, gender, antipsychotic type, route of administration and number of packages dispensed. Results A total of 117,811 patients were given any antipsychotic, of whom 71,004 regularly received such drugs. Among the latter, 9,855 (13.9%) corresponded to an antipsychotic combination, 47,386 (66.7%) to monotherapy and 13,763 (19.4%) to unspecified combinations. Of the patients given antipsychotics in association, 58% were men. Olanzapine (37.1%) and oral risperidone (36.4%) were the most common dispensations. Analysis of the patients dispensed two antipsychotics (57.8%) revealed 198 different combinations, the most frequent being the association of FGA and SGA (62.0%). Clozapine was dispensed to 2.3% of patients. Of those who were receiving antipsychotics in combination, 6.6% were given clozapine, being clozapine plus amisulpride the most frequent association (22.8%). A total of 3.800 patients (5.4%) were given LAI antipsychotics, and 2.662 of these (70.1%) were in combination. Risperidone was the most widely used LAI. Conclusions The scant evidence available regarding the efficacy of combining different antipsychotics contrasts with the high number and variety of combinations prescribed to outpatients, as well as with the limited use of clozapine.

On the molecular basis of ion permeation in the epithelial Na+ channel.

The epithelial Na+ channel (ENaC) is highly selective for Na+ and Li+ over K+ and is blocked by the diuretic amiloride. ENaC is a heterotetramer made of two alpha, one beta, and one gamma homologous subunits, each subunit comprising two transmembrane segments. Amino acid residues involved in binding of the pore blocker amiloride are located in the pre-M2 segment of beta and gamma subunits, which precedes the second putative transmembrane alpha helix (M2). A residue in the alpha subunit (alphaS589) at the NH2 terminus of M2 is critical for the molecular sieving properties of ENaC. ENaC is more permeable to Li+ than Na+ ions. The concentration of half-maximal unitary conductance is 38 mM for Na+ and 118 mM for Li+, a kinetic property that can account for the differences in Li+ and Na+ permeability. We show here that mutation of amino acid residues at homologous positions in the pre-M2 segment of alpha, beta, and gamma subunits (alphaG587, betaG529, gammaS541) decreases the Li+/Na+ selectivity by changing the apparent channel affinity for Li+ and Na+. Fitting single-channel data of the Li+ permeation to a discrete-state model including three barriers and two binding sites revealed that these mutations increased the energy needed for the translocation of Li+ from an outer ion binding site through the selectivity filter. Mutation of betaG529 to Ser, Cys, or Asp made ENaC partially permeable to K+ and larger ions, similar to the previously reported alphaS589 mutations. We conclude that the residues alphaG587 to alphaS589 and homologous residues in the beta and gamma subunits form the selectivity filter, which tightly accommodates Na+ and Li+ ions and excludes larger ions like K+.

Neuropeptide Y and corticotropin-releasing hormone in CSF mark response to antidepressive treatment with citalopram.

Neuropeptides appear to play a role in the pathophysiology of depression and electroconvulsive treatment and lithium affect these compounds in human cerebrospinal fluid (CSF) and rodent brain. Consequently, we investigated whether long-term treatment with the selective serotonin reuptake inhibitor (SSRI) citalopram (Cit) would also affect neuropeptides in CSF of depressed patients. Changes in CSF monoamine metabolites were also explored. CSF concentrations of corticotropin-releasing hormone (CRH)-like immunoreactivity (-LI), neuropeptide Y (NPY)-LI, and Cit were determined in 21 patients with major depression. Lumbar puncture was performed in the morning at baseline and was repeated after at least 4 wk of Cit treatment (40 mg/d). The severity of depression was assessed by the Hamilton Rating Scale for Depression (HAMD). Cit treatment was associated with a significant increase in NPY-LI and decrease in CRH-LI. An evaluation of the relationship between changes in concentrations of NPY-LI, CRH-LI, and the clinical response showed significant correlations between these parameters. Significant NPY and CRH changes in CSF following treatment as well as correlations to changes in HAMD support the hypothesis that these two peptides play a role in affective disorders and are markers of therapeutic response.

Freezing Point Depressions of Dilute Solutions of Alkali Metal Chlorides and Bromides

Freezing point depressions (¿Tf) of dilute solutions of several alkali metal chlorides and bromides were calculated by means of the best activity coefficient equations. In the calculations, Hückel, Hamer and Pitzer equationswere used for activity coefficients. The experimental ¿Tf values available in the literature for dilute LiCl, NaCl and KBr solutions can be predicted within experimental error by the Hückel equations used. The experimental ¿Tf values for dilute LiCl and KBr solutions can also be accurately calculated by corresponding Pitzer equations and those for dilute NaCl solutions by the Hamer equation for this salt. Neither Hamer nor Pitzer equations predict accurately the freezing points reported in the literature for LiBr and NaBr solutions. The ¿Tf values available for dilute solutions of RbCl, CsCl or CsBr are not known at the moment accurately because the existing data for these solutions are not precise. The freezing point depressions are tabulated in the present study for LiCl, NaCl and KBr solutions at several rounded molalities. The ¿Tf values in this table can be highly recommended. The activity coefficient equations used in the calculation of these values have been tested with almost allhigh-precision electrochemical data measured at 298.15 K.

From symmetric glycerol derivatives to dissymmetric chlorohydrins

The anticipated worldwide increase in biodiesel production will result in an accumulation of glycerol for which there are insufficient conventional uses. The surplus of this by-product has increased rapidly during the last decade, prompting a search for new glycerol applications. We describe here the synthesis of dissymmetric chlorohydrin esters from symmetric 1,3-dichloro-2-propyl esters obtained from glycerol. We studied the influence of two solvents: 1,4-dioxane and 1-butanol and two bases: sodium carbonate and 1-butylimidazole, on the synthesis of dissymmetric chlorohydrin esters. In addition, we studied the influence of other bases (potassium and lithium carbonates) in the reaction using 1,4-dioxane as the solvent. The highest yield was obtained using 1,4-dioxane and sodium carbonate.

Assessment of dissolution techniques for the analysis of ceramic samples by plasma spectrometry

In this study, 13 ceramic samples were subjected to dissolution using three different procedures: (a) acid attack in open PTFE vessels with a mixture of HF-HClO4, (b) fusion of the sample with lithium metaborate and (c) microwave digestion in PTFE bombs. The samples used in the study had been previously analyzed by neutron activation analysis (NAA), X-ray fluorescence (XRF) and X-ray diffraction (XRD) and they cover a wide range of ceramics fired in different atmospheres and temperatures as well as different mineralogical and chemical compositions. The effectiveness of each procedure is evaluated in terms of its ability to dissolve the various mineralogical phases of the samples, of the number of elements that can be determined and of the time needed for the whole scheme of analysis to be completed.

Pharmacovigilance [Pharmacovigilance update].

The main pharmacovigilance updates in 2014 are reviewed. Ivabradine: increased risk of cardiovascular death and myocardial infarction in patients with symptomatic angina treated with high dosages. Clopidogrel: rare observations of acquired hemophilia. Orlistat: may reduce the absorption of HIV antiretrovirals. Ponatinib: increased risk of arteriopathy and thrombosis. Axitinib: significant risk of heart failure (class effect). Tocilizumab: possible causal relationship with the emergence or aggravation of psoriasis. Lithium: hypercalcemia and hyperparathyroidism commonly observed. Sildenalfil: suspected causal association with melanoma, so far not proven, Methylphenidate: rare observations of priapism. St John's wort (Hypericum): reduced effectiveness of hormonal contraceptives, including implants.

L'hémodiayse intermittente, irremplaçable dans certains cas d'intoxications sévères [Intermittent hemodialysis, irreplaceable in specific cases of severe poisoning].

Le médecin praticien est souvent bien sensibilisé aux indications à l'hémodialyse au cours de l'insuffisance rénale sévère, que celle-ci soit aiguë ou chronique. En dehors des indications traditionnelles à une épuration extrarénale, il existe certaines situations comme des intoxications (metformine, éthylène glycol ou lithium) et d'autres conditions (hypercalcémie, lyse tumorale), dans lesquelles l'hémodialyse intermittente représente le traitement le plus efficace, voire le seul. Bien que ces situations demeurent peu fréquentes, il est décisif de les reconnaître rapidement The medical practitioner is in general well aware of the indications for hemodialysis in severe, acute or chronic renal insufficiency. Apart from the traditional indications for renal replacement therapy, there are some cases such as metfomin and ethylene glycol poisoning, lithium intoxication severe hypercalcemia and tumor lysis syndrome, in which intermittent hemodialysis is the most effective treatment, or sometimes the only effective one. Although these situations remain infrequent, it is crucial to recognize them as quickly as possible.

Teholähdepiirilevyn suunnittelu akkukäyttöiseen laitteeseen

Teholähdepiirilevyn suunnittelu etenkin kooltaan pieneen akkukäyttöiseen laitteeseen on monivaiheinen suunnitteluprosessi. Teholähdetopologioiden valinta levylle määrää heti alkuunsa kuinka vakaata jännitettä levyllä voidaan tuottaa, kuinka suuria tehoja siitä voidaan ottaa, miten paljon häiriöitä levy tuottaa ympäristöönsä ja ennen kaikkea, kun akkukäyttöisestä laitteesta on kysymys, kuinka hyvään hyötysuhteeseen sillä voidaan päästä. Suunnittelun kannalta hakkuriteholähde on teholähdetopologioista vaativin. Tässä työssä paneudutaankin tarkemmin boost-hakkuriteholähteen suunnitteluun. Pelkkä hakkurin komponenttien mitoitus ei takaa teholähteelle parasta mahdollista toimintaa, vaan myös piirilevysuunnittelulla on suuri merkitys. Akkukäyttöisen laitteen teholähdepiirilevyn suunnittelu ei rajoitu yksinomaan teholähteiden suunnitteluun vaan levy sisältää usein myös muuta oheiselektroniikkaa, yleensä ainakin laitteen käynnistyselektroniikan sekä akun latausjärjestelmän. Etenkin akun latausjärjestelmän suunnittelu saattaa muodostua hyvinkin monimutkaiseksi tehtäväksi. Tässä työssä onkin tutkittu muutaman yleisimmän akkutyypin latausmenetelmiä. Työssä suunnitellaan myös käytännössä teholähdepiirilevy akkukäyttöiseen mittalaitteeseen. Levyn toimintaa tutkitaan erinäisin mittauksin, joilla pyritään selvittämään levyn heikkoudet. Näiden heikkouksien pohjalta levystä suunnitellaan paranneltu versio. Tällekin levylle tehdään samat mittaukset kuin edelliselle versiolle, joista selviää parannusten onnistuminen.

Hyperpolarized (6) Li as a probe for hemoglobin oxygenation level.

Hyperpolarization by dissolution dynamic nuclear polarization (DNP) is a versatile technique to dramatically enhance the nuclear magnetic resonance (NMR) signal intensity of insensitive long-T1 nuclear spins such as (6) Li. The (6) Li longitudinal relaxation of lithium ions in aqueous solutions strongly depends on the concentration of paramagnetic species, even if they are present in minute amounts. We herein demonstrate that blood oxygenation can be readily detected by taking advantage of the (6) Li signal enhancement provided by dissolution DNP, together with the more than 10% decrease in (6) Li longitudinal relaxation as a consequence of the presence of paramagnetic deoxyhemoglobin. Copyright © 2015 John Wiley & Sons, Ltd.

Filmes de óxidos anódicos de nióbio: efeito eletrocrômico e cinética da reação de eletro-intercalação

The aim of this work is to study the electrochromism and the reaction kinetics of lithium electrointercalation in anodic niobium oxide films. The oxide grown in an acid environment by application of an alternating potential shows interference colour (iridescence) and when reduced in lithium perclorate/PC solution, the intercalation of Li+ ions and electrons causes a reversible colour change (electrochromism), characterized here by electrochemical and optical measurements. A model where the reaction kinetics is dominated by diffusion of ionic pairs (Li+, e-) in the oxide film permitted the reproduction of current and absorbance temporal dependence, confirming the relationship between the electrochromic and electrochemical reactions. From the results obtained, a relation was established where the colour change is associated to the reduction of Nb+5 to Nb+4 ions with simultaneous cations injection.