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Following democracy's global advance in the late 20th century, recent patterns of democratic erosion or 'backsliding' have generated extensive scholarly debate. Backsliding towards autocracy is often the work of elected leaders operating within democratic institutions, challenging conventional thinking about the logic of democratic consolidation, the enforcement of institutional checks and balances, and the development and reproduction of democratic norms. This volume tackles these challenges head-on, drawing theoretical insights from classic literature on democratic transitions and consolidation to help explain contemporary challenges to democracy. It offers a comparative perspective on the dynamics of democratic backsliding, the changing character of authoritarian threats, and the sources of democratic resiliency around the world. It also integrates the institutional, civil society, and international dimensions of contemporary challenges to democracy, while providing coverage of Western and Eastern Europe, South and Southeast Asia, Africa, Latin America, and the United States.
Artificial intelligence is dramatically reshaping scientific research and is coming to play an essential role in scientific and technological development by enhancing and accelerating discovery across multiple fields. This book dives into the interplay between artificial intelligence and the quantum sciences; the outcome of a collaborative effort from world-leading experts. After presenting the key concepts and foundations of machine learning, a subfield of artificial intelligence, its applications in quantum chemistry and physics are presented in an accessible way, enabling readers to engage with emerging literature on machine learning in science. By examining its state-of-the-art applications, readers will discover how machine learning is being applied within their own field and appreciate its broader impact on science and technology. This book is accessible to undergraduates and more advanced readers from physics, chemistry, engineering, and computer science. Online resources include Jupyter notebooks to expand and develop upon key topics introduced in the book.
Diagnosis in psychiatry faces familiar challenges. Validity and utility remain elusive, and confusion regarding the fluid and arbitrary border between mental health and illness is increasing. The mainstream strategy has been conservative and iterative, retaining current nosology until something better emerges. However, this has led to stagnation. New conceptual frameworks are urgently required to catalyze a genuine paradigm shift.
Methods
We outline candidate strategies that could pave the way for such a paradigm shift. These include the Research Domain Criteria (RDoC), the Hierarchical Taxonomy of Psychopathology (HiTOP), and Clinical Staging, which all promote a blend of dimensional and categorical approaches.
Results
These alternative still heuristic transdiagnostic models provide varying levels of clinical and research utility. RDoC was intended to provide a framework to reorient research beyond the constraints of DSM. HiTOP began as a nosology derived from statistical methods and is now pursuing clinical utility. Clinical Staging aims to both expand the scope and refine the utility of diagnosis by the inclusion of the dimension of timing. None is yet fit for purpose. Yet they are relatively complementary, and it may be possible for them to operate as an ecosystem. Time will tell whether they have the capacity singly or jointly to deliver a paradigm shift.
Conclusions
Several heuristic models have been developed that separately or synergistically build infrastructure to enable new transdiagnostic research to define the structure, development, and mechanisms of mental disorders, to guide treatment and better meet the needs of patients, policymakers, and society.
Three Cannings brothers describe their intertwined but separate careers in Canadian biology: Rob as an entomologist, Syd as an entomologist and conservation biologist, and Dick as an ornithologist and politician. They emphasise the influence on their lives of the British Columbia’s Okanagan Valley where they grew up, the naturalist family in which they were raised, and the mentors who inspired them in their work. Bird study and nature interpretation in BC Parks were early enthusiasms and influences. Biological research, museum work, nature conservation, public education, and writing have dominated their careers. In Dick’s case, his public life has culminated in a decade of Canadian federal politics as a member of Parliament.
This article is modified from the closing plenary address presented at Entomology 2022, the joint annual meeting of the Entomological Society of America, the Entomological Society of Canada, and the Entomological Society of British Columbia, in Vancouver, British Columbia, Canada, 16 November 2022. The presentation also acted as the 2022 Heritage Lecture of the Entomological Society of Canada.
Vaccines have revolutionised the field of medicine, eradicating and controlling many diseases. Recent pandemic vaccine successes have highlighted the accelerated pace of vaccine development and deployment. Leveraging this momentum, attention has shifted to cancer vaccines and personalised cancer vaccines, aimed at targeting individual tumour-specific abnormalities. The UK, now regarded for its vaccine capabilities, is an ideal nation for pioneering cancer vaccine trials. This article convened experts to share insights and approaches to navigate the challenges of cancer vaccine development with personalised or precision cancer vaccines, as well as fixed vaccines. Emphasising partnership and proactive strategies, this article outlines the ambition to harness national and local system capabilities in the UK; to work in collaboration with potential pharmaceutic partners; and to seize the opportunity to deliver the pace for rapid advances in cancer vaccine technology.
Psychiatrists are often called to see nonpsychiatric patients in medical settings. Two potential reasons for a consult are neuroleptic malignant syndrome and serotonin syndrome; both are potential emergencies. They differ in cause and pathophysiology. However, they have certain things in common: Both are rare and may go unrecognized or misdiagnosed. In addition, the course of both syndromes depends on the speed of intervention, and delays can result in lasting complications or mortality. This chapter reviews the features of each syndrome, the diagnosis and differential, and the recommended treatment approaches.
Studies show stimulant medications are effective for different ADHD presentations (predominantly inattentive [IA], predominantly hyperactive-impulsive [HI] or combined [C]); however, few studies have evaluated nonstimulant efficacy in different ADHD presentations. Viloxazine ER [VLX ER] is a nonstimulant, FDA-approved medication for pediatric (≥6 yrs) and adult ADHD. This post-hoc analysis of 4 double-blind (DB), Phase 3, clinical trials (2 in adolescents [NCT03247517 and NCT03247556], 2 in children [NCT03247530 and NCT03247543]), evaluates VLX ER efficacy by ADHD presentation as derived from ADHD Rating Scale, 5th Edition (ADHD-RS-5) assessments at Baseline.
Methods
Children and adolescents with ADHD and an ADHD-RS-5 Total score ≥ 28 were eligible for enrollment. ADHD presentation was defined as a rating of ≥2 on at least 6 of 9 ADHD-RS-5 inattention items, or hyperactive-impulsive items or both. For each ADHD presentation, the change from Baseline (CFB) in ADHD-RS-5 Total score (primary outcome in each study) was assessed using mixed models for repeated measures (MMRM). Responder rate (secondary outcome), ≥50% reduction from baseline in ADHD-RS-5 Total score, was analyzed using generalized estimating equations (GEE).
Results
Of 1354 subjects [placebo N = 452, VLX ER N = 902], ADHD presentation was assigned as 288 (21.3%) [IA], 1010 (74.5%) [C], 40 (3.0%) [HI], 16 (1.2%) [none of these]. Due to the small sample size of [HI], only the [IA] and [C] results are presented. At Week 6 (pooled data endpoint), ADHD-RS-5 Total scores were significantly improved for VLX ER relative to placebo for both the [IA] and [C] ADHD presentations. LS mean (SE) treatment differences, p-values were: [IA] -3.1 (1.35), p = 0.0219, and [C] 5.8 (0.97), p < 0.0001. Responder rates were also significantly higher for VLX ER: 43.0% [IA] and 42.7% [C] relative to placebo 29.5% [IA] and 25.5 % [C] (p=.0311 and p<.0001).
Conclusions
Viloxazine ER significantly reduced ADHD symptoms in individuals meeting criteria for ADHD [IA] or [C] presentations at Baseline. Limitations include post-hoc methodology, smaller sample sizes of [IA] and [HI] groups, and the ADHD-RS-5 ≥ 28 eligibility requirement, that may favor enrollment of individuals with ADHD [C] over ADHD [IA] or [HI] presentations. Consistency of response during long-term use should be evaluated.
The European Clozapine Task Force is a group of psychiatrists and pharmacologists practicing in 18 countries under European Medicines Agency (EMA) regulation, who are deeply concerned about the underuse of clozapine in European countries. Although clozapine is the most effective antipsychotic for people with treatment-resistant schizophrenia, a large proportion of them do not have access to this treatment. Concerns about clozapine-induced agranulocytosis and stringent blood monitoring rules are major barriers to clozapine prescribing and use. There is a growing body of evidence that the incidence of clozapine-induced agranulocytosis is very low after the first year of treatment. Maintaining lifelong monthly blood monitoring after this period contributes to unjustified discontinuation of clozapine. We leverage recent and replicated evidence on the long-term safety of clozapine to call for the revision and updating of the EMA’s blood monitoring rules, thus aiming to overcome this major barrier to clozapine prescribing and use. We believe the time has come for relaxing the rules without increasing the risks for people using clozapine in Europe.
A theoretical discussion of the factor pattern of predictor tests and criterion shows that ordinary test selection methods break down under certain circumstances. It is shown that maximal results may not occur if suppressor variables are present among the predictors. Suggested solutions to the problem include: (1) prior item analysis of tests against the criterion, (2) selection of several trial batteries including some with suppressor variables on the basis of a factor analysis of tests and criterion, (3) modification of the usual test selection procedures to include separate solutions based upon each of several starting variables, or (4) the cumbersome and tedious solution of all possible combinations of predictors. The solutions are recommended in the order named above. Although all of the suggested solutions involve added labor and may not be necessary, the test or battery constructor should at least be aware of the problem.
A method of generating any number of score and correlation matrices with arbitrary population parameters is described. Either Z scores or stanines are sampled from a normal population to represent factor scores by an IBM 1620 program. These are converted to variates from a population with an a priori factor structure. The effectiveness of the method is illustrated from research data. Some further modifications and uses of the method are discussed.
A method whereby biographical or other questionnaire data of a purely qualitative nature may be used to predict success or failure on an independent criterion is presented. The method is not new but the present least-squares derivation and the transformation equation for punched card coding were not available in the literature. The proper weights are found to be proportional to the per cent of passers in the various categories. The method is suggested as a suitable substitute for non-linear approaches in connection with purely quantitative data as well. The implications of reweighting in connection with multiple regression is discussed. The lavish use of degrees of freedom makes cross-validation extremely desirable.
Standard procedures for drawing inferences from complex samples do not apply when the variable of interest θ cannot be observed directly, but must be inferred from the values of secondary random variables that depend on θ stochastically. Examples are proficiency variables in item response models and class memberships in latent class models. Rubin's “multiple imputation” techniques yield approximations of sample statistics that would have been obtained, had θ been observable, and associated variance estimates that account for uncertainty due to both the sampling of respondents and the latent nature of θ. The approach is illustrated with data from the National Assessment for Educational Progress.
A model is presented for item responses when different subjects employ different strategies, but only responses, not choice of strategy, can be observed. Using substantive theory to differentiate the likelihoods of response vectors under a fixed set of strategies, we model response probabilities in terms of item parameters for each strategy, proportions of subjects employing each strategy, and distributions of subject proficiency within strategies. The probabilities that an individual subject employed the various strategies can then be obtained, along with a conditional estimate of proficiency under each. A conceptual example discusses response strategies for spatial rotation tasks, and a numerican example resolves a population of subjects into subpopulations of valid responders and random guessers.
Fifty-three tests designed to measure aspects of creative thinking were administered to 410 air cadets and student officers. The scores were intercorrelated and 16 factors were extracted. Orthogonal rotations resulted in 14 identifiable factors, a doublet, and a residual. Nine previously identified factors were: verbal comprehension, numerical facility, perceptual speed, visualization, general reasoning, word fluency, associational fluency, ideational fluency, and a factor combining Thurstone's closure I and II. Five new factors were identified as originality, redefinition, adaptive flexibility, spontaneous flexibility, and sensitivity to problems.
Joint correspondence analysis is a technique for constructing reduced-dimensional representations of pairwise relationships among categorical variables. The technique was proposed by Greenacre as an alternative to multiple correspondence analysis. Joint correspondence analysis differs from multiple correspondence analysis in that it focuses solely on between-variable relationships. Greenacre described one alternating least-squares algorithm for conducting joint correspondence analysis. Another alternating least-squares algorithm is described in this article. The algorithm is guaranteed to converge, and does so in fewer iterations than does the algorithm proposed by Greenacre. A modification of the algorithm for handling Heywood cases is described. The algorithm is illustrated on two data sets.
Item response theory models posit latent variables to account for regularities in students' performances on test items. Wilson's “Saltus” model extends the ideas of IRT to development that occurs in stages, where expected changes can be discontinuous, show different patterns for different types of items, or even exhibit reversals in probabilities of success on certain tasks. Examples include Piagetian stages of psychological development and Siegler's rule-based learning. This paper derives marginal maximum likelihood (MML) estimation equations for the structural parameters of the Saltus model and suggests a computing approximation based on the EM algorithm. For individual examinees, empirical Bayes probabilities of learning-stage are given, along with proficiency parameter estimates conditional on stage membership. The MML solution is illustrated with simulated data and an example from the domain of mixed number subtraction.
In this paper implicit function-based parameterizations for orthogonal and oblique rotation matrices are proposed. The parameterizations are used to construct Newton algorithms for minimizing differentiable rotation criteria applied to m factors and p variables. The speed of the new algorithms is compared to that of existing algorithms and to that of Newton algorithms based on alternative parameterizations. Several rotation criteria were examined and the algorithms were evaluated over a range of values for m. Initial guesses for Newton algorithms were improved by subconvergence iterations of the gradient projection algorithm. Simulation results suggest that no one algorithm is fastest for minimizing all criteria for all values of m. Among competing algorithms, the gradient projection algorithm alone was faster than the implicit function algorithm for minimizing a quartic criterion over oblique rotation matrices when m is large. In all other conditions, however, the implicit function algorithms were competitive with or faster than the fastest existing algorithms. The new algorithms showed the greatest advantage over other algorithms when minimizing a nonquartic component loss criterion.
When a simple sum or number-correct score is used to evaluate the ability of individual testees, then, from an accountability perspective, the inferences based on the sum score should be the same as the inferences based on the complete response pattern. This requirement is fulfilled if the sum score is a sufficient statistic for the parameter of a unidimensional model. However, the models for which this holds true are known to be restrictive. It is shown that the less restrictive nonparametric models could result in an ordering of persons that is different from an ordering based on the sum score. To arrive at a fair evaluation of ability with a simple number-correct score, ordinal sufficiency is defined as a minimum condition for scoring. The monotone homogeneity model, together with the property of ordinal sufficiency of the sum score, is introduced as the nonparametric Rasch model. A basic outline for testable hypotheses about ordinal sufficiency, as well as illustrations with real data, is provided.