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Epoxy resins coatings are commonly found in corrosion protection coatings but the presence of water can affect their adhesion to the substrate, often weakening the adhesion of the coating to the solid, reducing its efficiency. Nevertheless, small amounts of water can enhance the epoxy/substrate interactions. In this work, the interphase region of an epoxy precursor and metal oxide substrates is investigated using molecular simulations and it is found that water accumulates between the epoxy layer and the solid substrate. At high water concentrations (9â wt %) the interaction between the epoxy precursor and the solid surface is weakened regardless of the nature of the solid, but at low water concentrations the nature of the solid surface becomes important. For hematite, the presence of water decreases the strength of adhesion but for goethite the presence of a small amount of water (3â wt %) enhances the adhesion to the surface resulting in a densification at the interface.
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Epoxy-based coatings are widely used in a range of industries as protective coatings. The performance of the final solid-polymer system is dependent on the physicochemical properties of the interface and the interaction between the polymer and the solid substrate. In this study, we perform atomistic molecular dynamics simulations to investigate the binding of a common component in epoxy resins, diglycidyl ether of bisphenol A (DGEBA), on two iron oxide surfaces, hematite (0001) and magnetite (100), and investigate the effect of surface hydroxylation on the binding energy. We show that adsorption of DGEBA on hematite is more favorable than on magnetite and that the adsorbed molecules are highly localized on the pristine hematite surface but mobile on highly hydroxylated hematite surfaces and magnetite surfaces irregardless of surface hydroxylation fraction. A high degree of hydroxylation significantly reduces the binding energy of DGEBA on hematite but not on magnetite. The free-energy calculations confirm the trends observed upon hydroxylation, but the magnitude of the potential of mean force is lower than the binding energy due to the entropic contributions. Therefore, it can be suggested that DGEBA will adsorb more strongly on a surface containing a higher content of hematite than magnetite and that the presence of hydroxyl groups will weaken this adsorption. The presence of hydroxyl groups increases mobility of the chains, which can affect the coating rigidity.
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AFM-IR combines the chemical sensitivity of infrared spectroscopy with the lateral resolution of scanning probe microscopy, allowing nanoscale chemical analysis of almost any organic material under ambient conditions. As a result, this versatile technique is rapidly gaining popularity among materials scientists. Here, we report a previously overlooked source of data and artifacts in AFM-IR analysis; reflection from the buried interface. Periodic arrays of gold on glass are used to show that the overall signal in AFM-IR is affected by the wavelength-dependent reflectivity and thermal response of the underlying substrate. Excitingly, this demonstrates that remote analysis of heterogeneities at the buried interface is possible alongside that of an overlying organic film. On the other hand, AFM-IR users should carefully consider the composition and topography of underlying substrates when interpreting nanoscale infrared data. The common practice of generating ratio images, or indeed the normalization of AFM-IR spectra, should be approached with caution in the presence of substrate heterogeneity or variable sample thickness.
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BACKGROUND: Antisocial personality disorder (AsPD) is associated with poor mental health, criminality, substance use and relationship difficulties. This review updates Gibbon 2010 (previous version of the review). OBJECTIVES: To evaluate the potential benefits and adverse effects of psychological interventions for adults with AsPD. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, 13 other databases and two trials registers up to 5 September 2019. We also searched reference lists and contacted study authors to identify studies. SELECTION CRITERIA: Randomised controlled trials of adults, where participants with an AsPD or dissocial personality disorder diagnosis comprised at least 75% of the sample randomly allocated to receive a psychological intervention, treatment-as-usual (TAU), waiting list or no treatment. The primary outcomes were aggression, reconviction, global state/functioning, social functioning and adverse events. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: This review includes 19 studies (eight new to this update), comparing a psychological intervention against TAU (also called 'standard Maintenance'(SM) in some studies). Eight of the 18 psychological interventions reported data on our primary outcomes. Four studies focussed exclusively on participants with AsPD, and 15 on subgroups of participants with AsPD. Data were available from only 10 studies involving 605 participants. Eight studies were conducted in the UK and North America, and one each in Iran, Denmark and the Netherlands. Study duration ranged from 4 to 156 weeks (median = 26 weeks). Most participants (75%) were male; the mean age was 35.5 years. Eleven studies (58%) were funded by research councils. Risk of bias was high for 13% of criteria, unclear for 54% and low for 33%. Cognitive behaviour therapy (CBT) + TAU versus TAU One study (52 participants) found no evidence of a difference between CBT + TAU and TAU for physical aggression (odds ratio (OR) 0.92, 95% CI 0.28 to 3.07; low-certainty evidence) for outpatients at 12 months post-intervention. One study (39 participants) found no evidence of a difference between CBT + TAU and TAU for social functioning (mean difference (MD) -1.60 points, 95% CI -5.21 to 2.01; very low-certainty evidence), measured by the Social Functioning Questionnaire (SFQ; range = 0-24), for outpatients at 12 months post-intervention. Impulsive lifestyle counselling (ILC) + TAU versus TAU One study (118 participants) found no evidence of a difference between ILC + TAU and TAU for trait aggression (assessed with Buss-Perry Aggression Questionnaire-Short Form) for outpatients at nine months (MD 0.07, CI -0.35 to 0.49; very low-certainty evidence). One study (142 participants) found no evidence of a difference between ILC + TAU and TAU alone for the adverse event of death (OR 0.40, 95% CI 0.04 to 4.54; very low-certainty evidence) or incarceration (OR 0.70, 95% CI 0.27 to 1.86; very low-certainty evidence) for outpatients between three and nine months follow-up. Contingency management (CM) + SM versus SM One study (83 participants) found evidence that, compared to SM alone, CM + SM may improve social functioning measured by family/social scores on the Addiction Severity Index (ASI; range = 0 (no problems) to 1 (severe problems); MD -0.08, 95% CI -0.14 to -0.02; low-certainty evidence) for outpatients at six months. 'Driving whilst intoxicated' programme (DWI) + incarceration versus incarceration One study (52 participants) found no evidence of a difference between DWI + incarceration and incarceration alone on reconviction rates (hazard ratio 0.56, CI -0.19 to 1.31; very low-certainty evidence) for prisoner participants at 24 months. Schema therapy (ST) versus TAU One study (30 participants in a secure psychiatric hospital, 87% had AsPD diagnosis) found no evidence of a difference between ST and TAU for the number of participants who were reconvicted (OR 2.81, 95% CI 0.11 to 74.56, P = 0.54) at three years. The same study found that ST may be more likely to improve social functioning (assessed by the mean number of days until patients gain unsupervised leave (MD -137.33, 95% CI -271.31 to -3.35) compared to TAU, and no evidence of a difference between the groups for overall adverse events, classified as the number of people experiencing a global negative outcome over a three-year period (OR 0.42, 95% CI 0.08 to 2.19). The certainty of the evidence for all outcomes was very low. Social problem-solving (SPS) + psychoeducation (PE) versus TAU One study (17 participants) found no evidence of a difference between SPS + PE and TAU for participants' level of social functioning (MD -1.60 points, 95% CI -5.43 to 2.23; very low-certainty evidence) assessed with the SFQ at six months post-intervention. Dialectical behaviour therapy versus TAU One study (skewed data, 14 participants) provided very low-certainty, narrative evidence that DBT may reduce the number of self-harm days for outpatients at two months post-intervention compared to TAU. Psychosocial risk management (PSRM; 'Resettle') versus TAU One study (skewed data, 35 participants) found no evidence of a difference between PSRM and TAU for a number of officially recorded offences at one year after release from prison. It also found no evidence of difference between the PSRM and TAU for the adverse event of death during the study period (OR 0.89, 95% CI 0.05 to 14.83, P = 0.94, 72 participants (90% had AsPD), 1 study, very low-certainty evidence). AUTHORS' CONCLUSIONS: There is very limited evidence available on psychological interventions for adults with AsPD. Few interventions addressed the primary outcomes of this review and, of the eight that did, only three (CM + SM, ST and DBT) showed evidence that the intervention may be more effective than the control condition. No intervention reported compelling evidence of change in antisocial behaviour. Overall, the certainty of the evidence was low or very low, meaning that we have little confidence in the effect estimates reported. The conclusions of this update have not changed from those of the original review, despite the addition of eight new studies. This highlights the ongoing need for further methodologically rigorous studies to yield further data to guide the development and application of psychological interventions for AsPD and may suggest that a new approach is required.
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Transtorno da Personalidade Antissocial/terapia , Psicoterapia/métodos , Adulto , Agressão/psicologia , Transtorno da Personalidade Antissocial/mortalidade , Transtornos Relacionados ao Uso de Cocaína/terapia , Terapia Cognitivo-Comportamental/métodos , Dirigir sob a Influência , Feminino , Humanos , Masculino , Prisioneiros/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Reincidência/estatística & dados numéricos , Recompensa , Resultado do TratamentoRESUMO
BACKGROUND: Antisocial personality disorder (AsPD) is associated with rule-breaking, criminality, substance use, unemployment, relationship difficulties, and premature death. Certain types of medication (drugs) may help people with AsPD. This review updates a previous Cochrane review, published in 2010. OBJECTIVES: To assess the benefits and adverse effects of pharmacological interventions for adults with AsPD. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, 13 other databases and two trials registers up to 5 September 2019. We also checked reference lists and contacted study authors to identify studies. SELECTION CRITERIA: Randomised controlled trials in which adults (age 18 years and over) with a diagnosis of AsPD or dissocial personality disorder were allocated to a pharmacological intervention or placebo control condition. DATA COLLECTION AND ANALYSIS: Four authors independently selected studies and extracted data. We assessed risk of bias and created 'Summary of findings tables' and assessed the certainty of the evidence using the GRADE framework. The primary outcomes were: aggression; reconviction; global state/global functioning; social functioning; and adverse events. MAIN RESULTS: We included 11 studies (three new to this update), involving 416 participants with AsPD. Most studies (10/11) were conducted in North America. Seven studies were conducted exclusively in an outpatient setting, one in an inpatient setting, and one in prison; two studies used multiple settings. The average age of participants ranged from 28.6 years to 45.1 years (overall mean age 39.6 years). Participants were predominantly (90%) male. Study duration ranged from 6 to 24 weeks, with no follow-up period. Data were available from only four studies involving 274 participants with AsPD. All the available data came from unreplicated, single reports, and did not allow independent statistical analysis to be conducted. Many review findings were limited to descriptive summaries based on analyses carried out and reported by the trial investigators. No study set out to recruit participants on the basis of having AsPD; many participants presented primarily with substance abuse problems. The studies reported on four primary outcomes and six secondary outcomes. Primary outcomes were aggression (six studies) global/state functioning (three studies), social functioning (one study), and adverse events (seven studies). Secondary outcomes were leaving the study early (eight studies), substance misuse (five studies), employment status (one study), impulsivity (one study), anger (three studies), and mental state (three studies). No study reported data on the primary outcome of reconviction or the secondary outcomes of quality of life, engagement with services, satisfaction with treatment, housing/accommodation status, economic outcomes or prison/service outcomes. Eleven different drugs were compared with placebo, but data for AsPD participants were only available for five comparisons. Three classes of drug were represented: antiepileptic; antidepressant; and dopamine agonist (anti-Parkinsonian) drugs. We considered selection bias to be unclear in 8/11 studies, attrition bias to be high in 7/11 studies, and performance bias to be low in 7/11 studies. Using GRADE, we rated the certainty of evidence for each outcome in this review as very low, meaning that we have very little confidence in the effect estimates reported. Phenytoin (antiepileptic) versus placebo One study (60 participants) reported very low-certainty evidence that phenytoin (300 mg/day), compared to placebo, may reduce the mean frequency of aggressive acts per week (phenytoin mean = 0.33, no standard deviation (SD) reported; placebo mean = 0.51, no SD reported) in male prisoners with aggression (skewed data) at endpoint (six weeks). The same study (60 participants) reported no evidence of difference between phenytoin and placebo in the number of participants reporting the adverse event of nausea during week one (odds ratio (OR) 1.00, 95% confidence interval (CI) 0.06 to 16.76; very low-certainty evidence). The study authors also reported that no important side effects were detectable via blood cell counts or liver enzyme tests (very low-certainty evidence). The study did not measure reconviction, global/state functioning or social functioning. Desipramine (antidepressant) versus placebo One study (29 participants) reported no evidence of a difference between desipramine (250 to 300 mg/day) and placebo on mean social functioning scores (desipramine = 0.19; placebo = 0.21), assessed with the family-social domain of the Addiction Severity Index (scores range from zero to one, with higher values indicating worse social functioning), at endpoint (12 weeks) (very low-certainty evidence). Neither of the studies included in this comparison measured the other primary outcomes: aggression; reconviction; global/state functioning; or adverse events. Nortriptyline (antidepressant) versus placebo One study (20 participants) reported no evidence of a difference between nortriptyline (25 to 75 mg/day) and placebo on mean global state/functioning scores (nortriptyline = 0.3; placebo = 0.7), assessed with the Symptom Check List-90 (SCL-90) Global Severity Index (GSI; mean of subscale scores, ranging from zero to four, with higher scores indicating greater severity of symptoms), at endpoint (six months) in men with alcohol dependency (very low-certainty evidence). The study measured side effects but did not report data on adverse events for the AsPD subgroup. The study did not measure aggression, reconviction or social functioning. Bromocriptine (dopamine agonist) versus placebo One study (18 participants) reported no evidence of difference between bromocriptine (15 mg/day) and placebo on mean global state/functioning scores (bromocriptine = 0.4; placebo = 0.7), measured with the GSI of the SCL-90 at endpoint (six months) (very low-certainty evidence). The study did not provide data on adverse effects, but reported that 12 patients randomised to the bromocriptine group experienced severe side effects, five of whom dropped out of the study in the first two days due to nausea and severe flu-like symptoms (very low-certainty evidence). The study did not measure aggression, reconviction and social functioning. Amantadine (dopamine agonist) versus placebo The study in this comparison did not measure any of the primary outcomes. AUTHORS' CONCLUSIONS: The evidence summarised in this review is insufficient to draw any conclusion about the use of pharmacological interventions in the treatment of antisocial personality disorder. The evidence comes from single, unreplicated studies of mostly older medications. The studies also have methodological issues that severely limit the confidence we can draw from their results. Future studies should recruit participants on the basis of having AsPD, and use relevant outcome measures, including reconviction.
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Transtorno da Personalidade Antissocial/tratamento farmacológico , Psicotrópicos/uso terapêutico , Adulto , Agressão/efeitos dos fármacos , Transtornos Relacionados ao Uso de Álcool/tratamento farmacológico , Amantadina/uso terapêutico , Ansiedade/tratamento farmacológico , Bromocriptina/uso terapêutico , Desipramina/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nortriptilina/uso terapêutico , Fenitoína/uso terapêutico , Placebos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
HYPOTHESIS: Interphase properties in composites, adhesives and protective coatings can be predicted on the basis of interfacial interactions between polymeric precursor molecules and the inorganic surface during network formation. The strength of molecular interactions is expected to determine local segmental mobility (polymer glass transition temperature, Tg) and cure degree. EXPERIMENTS: Conventional analysis techniques and atomic force microscopy coupled with infrared (AFM-IR) are applied to nanocomposite specimens to precisely characterise the epoxy-amine/iron oxide interphase, whilst molecular dynamics simulations are applied to identify the molecular interactions underpinning its formation. FINDINGS: Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and high-resolution AFM-IR mapping confirm the presence of nanoscale under-cured interphase regions. Interfacial segregation of the molecular triethylenetetraamine (TETA) cross-linker results in an excess of epoxy functionality near synthetic hematite, (Fe2O3) magnetite (Fe3O4) and goethite (Fe(O)OH) particle surfaces. This occurs independently of the variable surface binding energies, as a result of entropic segregation during the cure. Thermal analysis and molecular dynamics simulations demonstrate that restricted segmental motion is imparted by strong interfacial binding between surface Fe sites in goethite, where the position of surface hydroxyl protons enables synergistic hydrogen bonding and electrostatic binding to Fe atoms at specific sites. This provides a strong driving force for molecular orientation resulting in significantly raised Tg values for the goethite composite samples.
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Compostos Férricos , Óxido Ferroso-Férrico , Aminas , InterfaseRESUMO
Background: Data from case series suggest that clozapine may benefit inpatients with borderline personality disorder (BPD), but randomised trials have not been conducted. Methods: Multicentre, double-blind, placebo-controlled trial. We aimed to recruit 222 inpatients with severe BPD aged 18 or over, who had failed to respond to other antipsychotic medications. We randomly allocated participants on a 1:1 ratio to receive up to 400 mg of clozapine per day or an inert placebo using a remote web-based randomisation service. The primary outcome was total score on the Zanarini Rating scale for Borderline Personality Disorder (ZAN-BPD) at 6 months. Secondary outcomes included self-harm, aggression, resource use and costs, side effects and adverse events. We used a modified intention to treat analysis (mITT) restricted to those who took one or more dose of trial medication, using a general linear model fitted at 6 months adjusted for baseline score, allocation group and site. Results: The study closed early due to poor recruitment and the impact of the COVID-19 pandemic. Of 29 study participants, 24 (83%) were followed up at 6 months, of whom 21 (72%) were included in the mITT analysis. At 6 months, 11 (73%) participants assigned to clozapine and 6 (43%) of those assigned to placebo were still taking trial medication. Adjusted difference in mean total ZAN-BPD score at 6 months was -3.86 (95% Confidence Intervals = -10.04 to 2.32). There were 14 serious adverse events; 6 in the clozapine arm and 8 in the placebo arm of the trial. There was little difference in the cost of care between groups. Interpretation: We recruited insufficient participants to test the primary hypothesis. The study findings highlight problems in conducting placebo-controlled trials of clozapine and in using clozapine for people with BPD, outside specialist inpatient mental health units. Trial registration: ISRCTN18352058. https://doi.org/10.1186/ISRCTN18352058.
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This is the protocol for a review and there is no abstract. The objectives are as follows: To evaluate the effects of pharmacological interventions for people with Schizotypal Personality Disorder (SzPD).
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This is the protocol for a review and there is no abstract. The objectives are as follows: To evaluate the effects of pharmacological interventions for people with paranoid personality disorder (PPD).
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Patients in medium secure hospitals may be at particularly increased risk of coronavirus disease 2019 (COVID-19) infection and complications. We undertook a service evaluation involving all current in-patients within a single, English medium secure hospital to describe the uptake of the COVID-19 vaccine among this population. Data regarding capacity to consent to the vaccine, acceptance/refusal of this (and reasons for refusal) and demographics was retrospectively collected from the patients' clinical records and analysed. In total, 85 patients (92.4% of eligible patients) had capacity to decide if they wanted the COVID-19 vaccine. Of these 68 (80.0%) consented and 17 (20.0%) declined to consent. A similar proportion of patients aged under and over 40 years old consented to have the vaccine. Those from a Black Asian minority ethnic background were more likely to decline the vaccine than White British patients. The reasons for capacitous refusal appeared similar to those seen in the general population.
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This is the protocol for a review and there is no abstract. The objectives are as follows: To evaluate the potential beneficial and adverse effects of psychological interventions for people with obsessive-compulsive personality disorder and to make recommendations for future areas of research.
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BACKGROUND: Antisocial personality disorder (AsPD) is associated with a wide range of disturbance including persistent rule-breaking, criminality, substance use, unemployment, homelessness and relationship difficulties. OBJECTIVES: To evaluate the potential beneficial and adverse effects of psychological interventions for people with AsPD. SEARCH STRATEGY: Our search included CENTRAL Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, PsycINFO, ASSIA, BIOSIS and COPAC. SELECTION CRITERIA: Prospective, controlled trials in which participants with AsPD were randomly allocated to a psychological intervention and a control condition (either treatment as usual, waiting list or no treatment). DATA COLLECTION AND ANALYSIS: Three authors independently selected studies. Two authors independently extracted data. We calculated mean differences, with odds ratios for dichotomous data. MAIN RESULTS: Eleven studies involving 471 participants with AsPD met the inclusion criteria, although data were available from only five studies involving 276 participants with AsPD. Only two studies focused solely on an AsPD sample. Eleven different psychological interventions were examined. Only two studies reported on reconviction, and only one on aggression. Compared to the control condition, cognitive behaviour therapy (CBT) plus standard maintenance was superior for outpatients with cocaine dependence in one study, but CBT plus treatment as usual was not superior for male outpatients with recent verbal/physical violence in another. Contingency management plus standard maintenance was superior for drug misuse for outpatients with cocaine dependence in one study but not in another, possibly because of differences in the behavioural intervention. However, contingency management was superior in social functioning and counselling session attendance in the latter. A multi-component intervention utilising motivational interviewing principles, the 'Driving Whilst Intoxicated program', plus incarceration was superior to incarceration alone for imprisoned drink-driving offenders. AUTHORS' CONCLUSIONS: Results suggest that there is insufficient trial evidence to justify using any psychological intervention for adults with AsPD. Disappointingly few of the included studies addressed the primary outcomes defined in this review (aggression, reconviction, global functioning, social functioning, adverse effects). Three interventions (contingency management with standard maintenance; CBT with standard maintenance; 'Driving Whilst Intoxicated program' with incarceration) appeared effective, compared to the control condition, in terms of improvement in at least one outcome in at least one study. Each of these interventions had been originally developed for people with substance misuse problems. Significant improvements were mainly confined to outcomes related to substance misuse. No study reported significant change in any specific antisocial behaviour. Further research is urgently needed for this prevalent and costly condition.
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Transtorno da Personalidade Antissocial/terapia , Psicoterapia/métodos , Adulto , Agressão/psicologia , Transtornos Relacionados ao Uso de Cocaína/terapia , Terapia Cognitivo-Comportamental/métodos , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , RecompensaRESUMO
BACKGROUND: Previous studies have demonstrated high levels of childhood adversity and familial criminality in offender patients with schizophrenia and/or personality disorder, but few have directly compared these groups. AIMS: To compare the parenting histories of offender patients with schizophrenia with those with personality disorder. We hypothesised that rates of family criminality and experiences of disrupted parenting would be higher in the personality disorder group than the schizophrenia group. METHOD: A retrospective case-control methodology compared the family background and childhood experiences of patients with either schizophrenia or personality disorder (n = 3088) admitted to any of the English high-security hospitals. RESULTS: Compared with those with schizophrenia, patients with personality disorder had experienced higher rates of family criminality, parental separation, and multiple changes of caregiver and institutional care. There was no significant difference in the prevalence of family psychiatric history between the groups. DISCUSSION: Although our hypotheses were sustained, we were impressed that rates of disruption to parenting were high in the schizophrenia group as well as in the personality disorder group. Less than a third of the personality disorder group had survived childhood without a change in parenting, but this was true for about half of the schizophrenia group, too. Family work tailored for people with schizophrenia is needed, even though within personality disorder services, a greater demand for disorder-sensitive family work is likely to be encountered.
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Internação Compulsória de Doente Mental , Transtornos da Personalidade/psicologia , Prisioneiros/psicologia , Psicologia do Esquizofrênico , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Inglaterra , Relações Familiares , Feminino , Hospitais Psiquiátricos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Pigment distributions have a critical role in the corrosion protection properties of organic paint coatings, but they are difficult to image in 3D over statistically significant volumes and at sufficiently high spatial resolutions required for detailed analysis. Here we report, for the first time, large volume analytical serial sectioning tomography of an organic composite coating using a xenon Plasma Focused Ion Beam (PFIB) combined with secondary electron imaging, energy dispersive X-ray (EDX) spectrum imaging (SI) and electron backscattered diffraction (EBSD). Together these techniques provide a comprehensive quantitative description of the physical orientation and distribution of the pigments within a model marine ballast tank coating, as well as their crystallographic and elemental characterisation. Polymers and organic materials are challenging because of their propensity for ion beam damage and possible beam heating effects. Our novel, optimised block preparation technique permits automated data acquisition with minimal operator intervention, and can have significant applications for the structural and chemical characterisation of a wide range of organic materials. Our results revealed that the paint contained 7.5 vol% aluminium flakes and 25 vol% quartz particles. The aluminium flakes were oriented parallel to the substrate surface, which is beneficial in terms of the corrosion protection capability of the coating.
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Polyphosphate corrosion inhibitors are increasingly marketed as chromate replacements for coil coated steel. The mechanisms underpinning corrosion prevention by these species is, however, not fully understood; corrosion inhibition is ordinarily assessed using electrochemical techniques, followed by ex-situ surface analysis. As a result, the formation of a clear film over cathodic sites is known to contribute to corrosion prevention, but little is known about its formation. Here, we apply advanced microscopy techniques (in-situ fluid cell AFM, SEM-EDX, and AFM-IR nano-chemical analysis) to examine early cathodic film formation by strontium aluminium polyphosphate (SAPP) in detail. For a model cut edge system, it is found that cathodic inhibition dominates during the first 24 hours of immersion, and surprisingly, that strontium carbonate impurities play a significant role. Rapidly precipitated zinc carbonate provides protection almost immediately after immersion, before the film structure evolves to include (poly)phosphate species. This suggests that the purposeful inclusion of carbonates may provide a new, environmentally sound approach to enhancing inhibitor efficacy.
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The first direct observation of a chemically heterogeneous nanostructure within an epoxy resin is reported. Epoxy resins comprise the matrix component of many high performance composites, coatings and adhesives, yet the molecular network structure that underpins the performance of these industrially essential materials is not well understood. Internal nodular morphologies have repeatedly been reported for epoxy resins analyzed using SEM or AFM, yet the origin of these features remains a contentious subject, and epoxies are still commonly assumed to be chemically homogeneous. Uniquely, in this contribution we use the recently developed AFM-IR technique to eliminate previous differences in interpretation, and establish that nodule features correspond to heterogeneous network connectivity within an epoxy phenolic formulation.
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OBJECTIVE: Outcomes for any mental health service will vary with the characteristics of those admitted as well as with the clinical provision of the service itself. This study aims to explore, for a medium secure forensic service in England, temporal changes in (1) characteristics of those admitted and (2) outcome after discharge and (3) to examine whether such changes are related. METHOD: Baseline characteristics and reconviction outcomes were derived from multiple data sources for 550 first admissions to a medium secure forensic unit for a 20-year period. Time to reconviction was examined using Kaplan-Meier analysis and Cox regression. RESULTS: Over time, severity of admissions increased, as did discharges to prison; discharges to non-secure hospitals reduced. Risk of reconviction increased by 3.9%-4.2% for each year of admission from 1983, which was explained by the increased admission of higher-risk patients. CONCLUSION: This medium secure service admitted patients with increasing levels of risk; reoffending rates reflect admission characteristics. Service funding decisions should take account of the characteristics of those admitted. SIGNIFICANT OUTCOMES: This study indicates that the profile of patients admitted over a 20-year period increased in severity. Over time, reconviction after discharge occurred earlier after release. This increase in reconviction was explained by the type of patient admitted. LIMITATIONS: Examination of a cohort from a single medium secure unit limits the generalizability of the findings. The study focuses on a criminological outcome measure (i.e. reconviction); other domains may be equally relevant (e.g. the relief of psychological distress). Examining an entire series of admissions introduces heterogeneity by, for example, considering the outcome of men and women together.