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Proof of correlation between psychotic spectrum disorders and suicide are found in literature, as well as between cannabis use disorder (CUD) and suicide and between CUD and schizophrenia. The study population of the selected papers consists of subjects diagnosed with schizophrenia spectrum or cannabis or SCs induced psychosis. Our objective is to assess how suicide risk (defined as suicidal ideation/attempt or death by suicide) in this population may vary with exposure to cannabis or one of its main active compounds. We searched PubMed, Scopus and Psycinfo database from January 2010 to February 2022. Study designs of the included articles are distributed as follows: 6 cross-sectional studies, 3 cohort studies, 1 case-control studies, 1 randomized double-blind study, 1 case report. Selected cohort studies seem to agree in identifying an increased suicide risk in patients with schizophrenia spectrum disorders when exposed to cannabis use. The case-control study and selected cross-sectionals provide contradictory data. However, qualitative analysis seem to point toward a positive correlation between cannabis use and increased suicidal risk in patients with schizophrenia spectrum disorders. In conclusion, emerging data on the correlation between cannabis use and suicide risk in patients with schizophrenia or other schizophrenic spectrum disorders are insufficient to draw firm conclusions. Nonetheless these studies seem to suggest a positive correlation of cannabis use with increased suicide risk, particularly regarding first episode psychosis (FEP) and male gender. Clinicians should be aware of the possibility of a higher risk of suicidal behavior associated specifically with cannabis use for men and patients during FEP.

Management of negative symptoms is one of the most challenging and important unmet needs of schizophrenia treatment. Negative symptoms together with positive symptoms result in significant psychosocial impairment and poor quality of life. Existing studies on atypical antipsychotics reported limited treatment adherence due to higher prevalence of treatment-emergent adverse events, such as diabetes, weight gain, hyperlipidemia, hyperprolactinemia and hypertension. A compound with greater affinity for dopamine D2/D3 receptors may improve negative symptoms, mood, and cognitive impairment associated with schizophrenia. In 2015, the US FDA has approved cariprazine, a partial D2/D3 agonist for treatment of schizophrenia, mania or mixed episodes. Midlands and Lancashire Commissioning Support Unit, UK (2019) has particularly suggested cariprazine for the treatment of predominant negative symptoms of schizophrenia. India's Central Drugs Standard Control Organization (CDSCO) has approved cariprazine in 2021 for the treatment of schizophrenia, manic or mixed episodes associated with bipolar I disorder. A ten-fold greater affinity for D3 receptors and partial agonism to serotonin receptors, along with longer half-lifemake cariprazine distinct when compared with other atypical antipsychotics. Cariprazine is also reported to have fewer incidents of metabolic and hormonal adverse events, and has been shown to provide better relapse prevention. Recent evidence indicates promising effect of cariprazine in ameliorating negative symptoms as well as psychotic symptoms in patients with schizophrenia. In addition, improved adherence to treatment (adjunctive/monotherapy) with cariprazine in patients having inadequate response to an ongoing antipsychotic treatment has also been clinically established. This review presents the evidence-based safety and efficacy of cariprazine for treatment of predominant negative symptoms of schizophrenia. [ABSTRACT FROM AUTHOR]

Background: Natural Cannabis (NC) and Synthetic Cannabinoids (SCs) use can increase the risk and exacerbate the course of psychotic disorders. These could be influenced by the Aberrant Salience (AS) construct. It refers to an excess of attribution of meaning to stimuli that are otherwise regarded as neutral, thereby transform them into adverse, dangerous, or mysterious entities. This leads the patient to engage in aberrant and consequently incorrect interpretative efforts concerning the normal perception of reality and its relationship with our analytical abilities. AS appears to play a significant role in the onset and perpetuation of psychotic disorders. The internal conflict arising from aberrant attributions of significance leads to delusional thoughts, ultimately culminating in the establishment of a self-sustaining psychosis. Aims: To examine the differences between psychoses course not associated with cannabis use and those associated with NC-use and SCs-use, in terms of psychotic and dissociative symptoms, AS, global functioning and suicidal ideation. Methods: A sample of 62 patients with First Episode Psychosis (FEP) was divided into 3 groups: non cannabis users (non-users, N = 20); NC-users or rather Delta-9-tetrahydrocannabinol (THC) users (THC-users, N = 21); SCs-users, commonly referred to as SPICE-users (SPICE-users, N = 20). Each group underwent assessments at the onset of psychotic symptoms, as well as at the 3 months and 6 months marks, utilizing a range of psychopathological scales. These included the Positive and Negative Syndrome Scale (PANSS) for investigating psychotic symptoms, the Global Assessment of Functioning (GAF) scale for assessing overall functioning, the Dissociative Experiences Scale (DES-II) for measuring dissociative symptoms, the Scale for Suicide Ideation (SSI) for evaluating suicidal ideation and the Aberrant Salience Inventory (ASI) scale for gauging AS. Results: SPICE-users showed more severe and persistent positive symptoms, while negative symptoms were mostly represented among non-users. Nonusers showed better recovery than SPICE-users in global functioning. All groups showed a decrease in both ASI scores and subscale scores. SPICE-users exhibited higher global AS scores and less improvement in this aspect compared to other groups. Conclusion: This study may help understanding the role of AS in both nonsubstance-related and substance-induced psychosis. This knowledge may lead clinician to a better diagnosis and identify patient-tailored psychopharmacological treatment. [ABSTRACT FROM AUTHOR]

The study of the development of visuospatial memory processes is useful for devising personalized educational interventions as well as for understanding the changes in cognitive functioning in an era characterized by technological progress. The present research is aimed at investigating spatial working memory ability in children that attended the first three years of primary school by means of the Brick Game Task (BGT), a novel visuospatial working memory test. BGT is a small-scale ecological test inspired by behavioral walking tasks with nine white bricks in different spatial configurations as well as to Corsi Block-Tapping test. 228 Italian children (121 F; mean age: 7.22 ± 1.18) were assigned to three groups based on the primary school class attended: Group 1 (N = 85; 40 F; mean age 6.18 ±.5), Group 2 (N = 61; 36 F; mean age 7.2 ±.83), and Group 3 (N = 82; 44 F; mean age 8.32 ±.94). All participants were asked to complete the Digit Span test, the Corsi Block-Tapping test, and to explore the three spatial configurations of the BGT with the form of Matrix, M-BGT, Cluster, CL-BGT, Cross, CR-BGT. MANOVA revealed a main significant effect for Group (F12,434 = 15.06; p <.0001) indicating that the group of older obtained a better global executive performance than 1 and 2 groups. Multiple linear regression indicated that Corsi Block-Tapping test performance and Age significantly predicted the M-BGT score. Moreover, Corsi Block-Tapping test and Digit Span significantly predicted the CL-BGT performance, showing how a higher score results in a better CL- BGT performance. Finally, Corsi Block-Tapping test, Digit Span, and Age were positively associated with the CR- BGT performance. The present findings evidenced that novel BGT is a sensible visuospatial working memory task suggesting thus its use to assess the children's executive performance in ecological way. These results open to the development of personalized educational interventions. [ABSTRACT FROM AUTHOR]

Emerging semiconductors for energy and information applications increasingly consist of compounds with much higher structural and chemical complexity than their unary and binary predecessors. Often, such complexity has limited the ultimate potential of new materials due to challenges with carrier concentration control in the face of native defects. For example, native defects in ordered vacancy compound Hg2GeTe4 impose challenging requirements for extrinsic doping to achieve carrier concentration levels suitable for thermoelectric performance. Here, we address this challenge by performing first-principles defect analysis on 16 extrinsic dopants under different synthetic conditions in Hg2GeTe4. Eight of these dopants (Au, Ag, Cu, Li, In, Ga, Zn, Sc) are predicted to tune the carrier concentration over three orders of magnitude. The remaining eight dopants (Na, Mg, Y, La, Sb, Bi, Br, I) have high formation energy and are predicted to have minimal impact. Samples with the eight most promising dopants were synthesized from elemental precursors and their transport property measurements are in excellent agreement with predicted values. Consistent with theory, degenerate n-type doping proves to be unavailable, and extrinsic compensating defects are understood to be the primary barrier. The p-type dopants were found to be effective; we obtained degenerate carrier concentration with Ag and decent thermoelectric performance (zT = 0.4 at 473 K). Shifting the Fermi level to the valence band edge reduces the concentration of VHg−2 and associated ionized defect scattering. Such observations highlight the interwoven network of dependencies when doping multinary semiconductors, and emphasize the importance of theory-experimental collaborations when exploring new materials. [ABSTRACT FROM AUTHOR]

Diamond like semiconductors (DLS) have emerged as candidates for thermoelectric energy conversion. Towards understanding and optimizing performance, we present a comprehensive investigation of the electronic properties of two DLS phases, quaternary Cu2HgGeTe4 and related ordered vacancy compound Hg2GeTe4, including thermodynamic stability, defect chemistry, and transport properties. To establish the thermodynamic link between the related but distinct phases, the stability region for both is visualized in chemical potential space. In spite of their similar structure and bonding, we show that the two materials exhibit reciprocal behaviors for dopability. Cu2HgGeTe4 is degenerately p-type in all environments despite its wide stability region, due to the presence of low-energy acceptor defects VCu and CuHg and is resistant to extrinsic n-type doping. Meanwhile Hg2GeTe4 has a narrow stability region and intrinsic behavior due to the relatively high formation energy of native defects, but presents an opportunity for bi-polar doping. While these two compounds have similar structure, bonding, and chemical constituents, the reciprocal nature of their dopability emerges from significant differences in band edge positions. A Brouwer band diagram approach is utilized to visualize the role of native defects on carrier concentrations, dopability, and transport properties. This study elucidates the doping asymmetry between two solid-solution forming DLS phases Cu2HgGeTe4 and Hg2GeTe4 by revealing the defect chemistry of each compound, and suggests design strategies for defect engineering of DLS phases. [ABSTRACT FROM AUTHOR]

A growing body of literature is concerned with 'healing' our cities, fostering an ethic of care for urban nature and creating more socially and environmentally just cities. At the same time, urban biodiversity is the focus of an increasing number of projects at multiple scales. However, in contrast to the ethos of multispecies 'entanglement' and 'becoming with' that typically animates this research, large numbers of animals 'entangled' in the machinations of our cities constitute a 'nature' that remains mostly unseen. And yet, it is the local and global practices these animals are part of – associated with food, entertainment, education, companionship and research – and the persistent relations of use and exploitation that underpin them, that are most directly implicated in the ongoing environmental degradation, destruction of habitats and extinction of species that create the 'problem' of urban biodiversity. We therefore argue that a persistent anthropocentrism is hampering efforts to respond effectively to the findings and recommendations of the IPCC, IPBES, FAO and others. Based on a thorough literature search and review of 65 articles concerned with urban 'nature' and multispecies relations, we demonstrate a prevailing hierarchy in how, and more importantly which, nonhuman species are being represented. Parallels are noted from recent social movements and the work of scholars from complementary fields. We highlight the dangers posed by this selective remit of care and concern and suggest critical animal studies as a way to adjust the frame and extend the boundaries of dominant thinking about what constitutes 'nature'. In conclusion, we call for researchers concerned with urban nature and biodiversity to adopt more critical and repoliticized understandings of 'nature' and multispecies relations – ones that are better poised to challenge practices involving commodified animals and slow the pace of environmental destructions and losses they are associated with. [ABSTRACT FROM AUTHOR]

The paper considers the cultural exploitation of bears, especially white ones, from the late sixteenth century to the present, both in drama and literary fiction and in the bear pits, theatres, circuses, zoos, and natural habitats in which real biological bears have found themselves mythologized and marketed. Beginning and ending with Bryndís Snæbjörnsdóttir and Mark Wilson's art project nanoq: flat out and bluesome (2006), the argument explores the use and abuse of fictive and real white bears in the changing contexts of Elizabethan and Jacobean politics and performance history, eighteenth and nineteenth century colonialism, and present day anxieties about habitat degradation and global warming, and also in the light of the perennial and "almost inescapable anthropomorphism" which, as Snæbjörnsdóttir and Wilson point out, causes us to see the bear as "a potent symbol" rather than a creature with its own life experience and autonomy. In addition to nanoq: flat out and bluesome, which attempts to break its audience out of that mind-set by confronting them with the mortal remains and individual histories of 34 taxidermic bears, the paper discusses George Peele's The Old Wives Tale (c. 1594), the anonymous 1590s play Mucedorus, Ben Jonson's masque Oberon, the Fairy Prince (1611), Laurence Sterne's Tristram Shandy (1760), Robert Bage's Jacobin novel Hermsprong (1796), James Hogg's novella The Surpassing Adventures of Allan Gordon (1834), Philip Pullman's Northern Lights (1995), Yoko Tawada's Memoirs of a Polar Bear (2016), and Martin Rowe's The Polar Bear in the Zoo (2013). [ABSTRACT FROM AUTHOR]