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Approximately 30% of patients with schizophrenia experience auditory hallucinations that are refractory to antipsychotic medications. Here, we evaluated the feasibility and efficacy of transcranial alternating current stimulation (tACS) that we hypothesized would improve auditory hallucination symptoms by enhancing synchronization between the frontal and temporo-parietal areas of the left hemisphere.
22 participants were randomized to one of three arms and received twice daily, 20 min sessions of sham, 10 Hz 2 mA peak-to-peak tACS, or 2 mA tDCS over the course of 5 consecutive days. Symptom improvement was assessed using the Auditory Hallucination Rating Scale (AHRS) as the primary outcome measure. The Positive and Negative Syndrome Scale (PANSS) and the Brief Assessment of Cognition in Schizophrenia (BACS) were secondary outcomes.
Primary and secondary behavioral outcomes were not significantly different between the three arms. However, effect size analyses show that tACS had the greatest effect based on the auditory hallucinations scale for the week of stimulation (1.31 for tACS; 1.06 and 0.17, for sham and tDCS, respectively). Effect size analysis for the secondary outcomes revealed heterogeneous results across measures and stimulation conditions.
To our knowledge, this is the first clinical trial of tACS for the treatment of symptoms of a psychiatric condition. Further studies with larger sample sizes are needed to better understand the effect of tACS on auditory hallucinations.
Dolfi, Guralnick, Praeger and Spiga asked whether there exist infinitely many primitive groups of twisted wreath type with non-trivial coprime subdegrees. Here, we settle this question in the affirmative. We construct infinite families of primitive twisted wreath permutation groups with non-trivial coprime subdegrees. In particular, we define a primitive twisted wreath group G(m, q) constructed from the non-abelian simple group PSL(2, q) and a primitive permutation group of diagonal type with socle PSL(2, q)m, and determine many subdegrees for this group. A consequence is that we determine all values of m and q for which G(m, q) has non-trivial coprime subdegrees. In the case where m = 2 and
, we obtain a full classification of all pairs of non-trivial coprime subdegrees.
The value of the nosological distinction between non-affective and affective psychosis has frequently been challenged. We aimed to investigate the transdiagnostic dimensional structure and associated characteristics of psychopathology at First Episode Psychosis (FEP). Regardless of diagnostic categories, we expected that positive symptoms occurred more frequently in ethnic minority groups and in more densely populated environments, and that negative symptoms were associated with indices of neurodevelopmental impairment.
This study included 2182 FEP individuals recruited across six countries, as part of the EUropean network of national schizophrenia networks studying Gene–Environment Interactions (EU-GEI) study. Symptom ratings were analysed using multidimensional item response modelling in Mplus to estimate five theory-based models of psychosis. We used multiple regression models to examine demographic and context factors associated with symptom dimensions.
A bifactor model, composed of one general factor and five specific dimensions of positive, negative, disorganization, manic and depressive symptoms, best-represented associations among ratings of psychotic symptoms. Positive symptoms were more common in ethnic minority groups. Urbanicity was associated with a higher score on the general factor. Men presented with more negative and less depressive symptoms than women. Early age-at-first-contact with psychiatric services was associated with higher scores on negative, disorganized, and manic symptom dimensions.
Our results suggest that the bifactor model of psychopathology holds across diagnostic categories of non-affective and affective psychosis at FEP, and demographic and context determinants map onto general and specific symptom dimensions. These findings have implications for tailoring symptom-specific treatments and inform research into the mood-psychosis spectrum.
We investigate the behaviour of Tamagawa numbers of semistable principally polarised abelian varieties in extensions of local fields. In particular, we give a simple formula for the change of Tamagawa numbers in totally ramified extensions and one that computes Tamagawa numbers up to rational squares in general extensions. As an application, we extend some of the existing results on the p-parity conjecture for Selmer groups of abelian varieties by allowing more general local behaviour. We also give a complete classification of the behaviour of Tamagawa numbers for semistable 2-dimensional principally polarised abelian varieties that is similar to the well-known one for elliptic curves. The appendix explains how to use this classification for Jacobians of genus 2 hyperelliptic curves given by equations of the form y2 = f(x), under some simplifying hypotheses.
Relational security is an important component of care and risk assessment in mental health services, but the utility of available measures remains under-researched. This study analysed the psychometric properties of two relational security tools, the See Think Act (STA) scale and the Relational Security Explorer (RSE).
The STA scale had good internal consistency and could highlight differences between occupational groups, whereas the RSE did not perform well as a psychometric measure.
The measures provide unique and complimentary perspectives on the quality of relational security within secure services, but have some limitations. Use of the RSE should be restricted to its intended purpose; to guide team discussions about relational security, and services should refrain from collecting and aggregating this data. Until further research validates their use, relational security measurement should be multidimensional and form part of a wider process of service quality assessment.
A randomized clinical trial was conducted to evaluate the efficacy of interpersonal psychotherapy (IPT) for ethnically and racially diverse, economically disadvantaged women with major depressive disorder. Non-treatment-seeking urban women (N = 128; M age = 25.40, SD = 4.98) with infants were recruited from the community. Participants were at or below the poverty level: 59.4% were Black and 21.1% were Hispanic. Women were screened for depressive symptoms using the Center for Epidemiologic Studies Depression Scale; the Diagnostic Interview Schedule was used to confirm major depressive disorder diagnosis. Participants were randomized to individual IPT or enhanced community standard. Depressive symptoms were assessed before, after, and 8 months posttreatment with the Beck Depression Inventory—II and the Revised Hamilton Rating Scale for Depression. The Social Support Behaviors Scale, the Social Adjustment Scale—Self-Report, and the Perceived Stress Scale were administered to examine mediators of outcome at follow-up. Treatment effects were evaluated with a growth mixture model for randomized trials using complier-average causal effect estimation. Depressive symptoms trajectories from baseline through postintervention to follow-up showed significant decreases among the IPT group compared to the enhanced community standard group. Changes on the Perceived Stress Scale and the Social Support Behaviors Scale mediated sustained treatment outcome.
The purpose of this work is the development and control of a high temperature reactor for the production of engineered nanoparticles, taking advantage from our previous studies on combustion-generated fine carbonaceous particles. The reactor consists of a laminar premixed flame, homogenously doped with monodisperse droplets of metal precursors dissolved or dispersed in volatile solvents. The droplets are generated by a vibrating orifice aerosol generator, and injected directly into the burner. Fuel-lean and stoichiometric flames allow producing pure metal oxide particles of nanometric sizes.
Particles are collected by thermophoresis inserting a cold substrate in the flame by means of a pneumatic actuator. Morphological and dimensional analysis are performed on the collected particles by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). SEM and AFM allow inferring both qualitative and quantitative information on many physical properties including size, morphology, surface texture and roughness.
Experimental results have been obtained from a premixed stoichiometric flame of ethylene and air, doped with 75 microns droplets of magnesium nitrate hexahydrate dissolved in ethanol. Roughly monodisperse magnesium oxide particles, having a desired size ranging from 50 nm down to 7 nm, have been produced by altering the precursor concentration in the solution and the residence time of the synthesis process.
We used mandatory public reporting as an impetus to perform a statewide study to define risk factors for surgical site infection. Among women who underwent abdominal hysterectomy, blood transfusion was a significant risk factor for surgical site infection in patients who experienced blood loss of less than 500 mL.
People who use cannabis have an increased risk of psychosis an effect attributed to the active ingredient δ9-tetrahydrocannabinol (Δ9-THC). There has recently been concern over an increase in the concentration of Δ9-THC in the cannabis available in many countries.
To investigate whether people with a first episode of psychosis were particularly likely to use high-potency cannabis.
We collected information on cannabis use from 280 cases presenting with a first episode of psychosis to the South London & Maudsley National Health Service (NHS) Foundation Trust, and from 174 healthy controls recruited from the local population.
There was no significant difference between cases and controls in whether they had ever taken cannabis, or age at first use. However, those in the cases group were more likely to be current daily users (OR = 6.4) and to have smoked cannabis for more than 5 years (OR = 2.1). Among those who used cannabis, 78% of the cases group used high-potency cannabis (sinsemilla, ‘skunk’) compared with 37% of the control group (OR 6.8).
The finding that people with a first episode of psychosis had smoked higher-potency cannabis, for longer and with greater frequency, than a healthy control group is consistent with the hypothesis that Δ9-THC is the active ingredient increasing risk of psychosis. This has important public health implications, given the increased availability and use of high-potency cannabis.
Current polyamide 11 and 12 are lacking in fire retardancy and high strength/high heat resistance characteristics for fabricated parts that are required for performance driven applications. The introduction of selected nanoparticles such as carbon nanofibers (CNFs), combined with a conventional intumescent flame retardant (FR) additive into the polyamide 11/polyamide 12 (PA11/PA12) by melt processing conditions has resulted in a family of intumescent polyamide nanocomposites. These intumescent PA11 and PA12 nanocomposites exhibit enhanced polymer performance characteristics, i.e., fire retardancy, high strength, and high heat resistance and are expected to expand the market opportunities for resin manufacturers. The overall objective of this research is to develop improved PA11 and PA12 polymers with enhanced flame retardancy, thermal, and mechanical properties for selective laser sintering (SLS) rapid manufacturing. Arkema RILSAN® PA11 polymer was examined with CNFs and Clairant Exolit® OP 1230 intumescent FR additive. They were used to create a family of FR intumescent PA11-CNF nanocomposites. Transmission electron microscopy (TEM) was used to determine the degree of CNFs and intumescent FR additive dispersion in PA11. Injection molded specimens were fabricated for material properties measurements. Thermal stability of these polymer nanocomposites (PNs) was examined by TGA. Flammability and thermal properties of these PNs were obtained using the cone calorimeter, UL 94 test method, and heat deflection temperature.
A few years ago a battered infant was admitted to
a California hospital. After a period of observation
and testing, the physicians concluded that the infant had
been beaten so badly that his brain was almost completely
destroyed, leaving him permanently unconscious. The hospital
had just adopted a policy specifying that life-sustaining
treatment for permanent unconsciousness was futile and,
therefore, not indicated. According to this policy, after
suitable subspecialty consultations and deliberations,
including efforts to gain parental agreement and documentation
of unanimous ethics committee support, the patient's
physician had the authority to discontinue life-sustaining
treatment. The infant's physician wished to do this.
The mother, however, who was the prime battery suspect,
insisted that the baby be kept alive.
Lutzomyia lichyi (Floch & Abbonenc) is a suggested secondary vector of Leishmania in Colombia. Taxonomically, L. lichyi is very closely related to the L. longipalpis (Lutz & Neiva) species complex. Male members of the complex can be distinguished by their sex pheromones which are produced in papules found grouped together in pale patches on tergites 3 or tergites 3 and 4. Male L. lichyi also have papules, very similar in appearance to those of the L. longipalpis species complex but distributed on tergites 4, 5, 6 and 7. Chemical analysis of male L. lichyi hexane extracts has revealed the presence of two novel oxygenated methylsesquiterpenes. The two major oxygenated terpenes found in the extract of L. lichyi males are tentatively characterized as a primary and tertiary alcohol. The mass spectrum of the proposed primary alcohol is very similar to the published mass spectrum of 3-methyl-α-himachalene, the sex pheromone produced by the Jacobina chemotype of the L. longipalpis complex. The mass spectrum of the proposed tertiary alcohol also has similarities to the 3-methyl-α-himachalene sex pheromone.