A formal description of a database consists of the description of the relations (tables) of the database together with the constraints that must hold on the database. Furthermore the contents of a database can be retrieved using queries. These constraints and queries for databases can very well be formalized. A formal description of a constraint or a query is necessary to describe the constraint or query unambiguously. In other words, a formal description leads to one and only one meaning of the constraint or query. To describe constraints and queries in a formal way we use predicate logic, set theory and tuple relational calculus. The tuple relational calculus is a calculus based on the use of tuple variables. A tuple variable is a variable that ranges over a named relation (i.e. a set of tuples of a relation). This paper describes the use of the relational calculus for databases. A description of the formal notation is given as well as a mapping of these expressions to SQL.
Formal elements are often used in art therapy assessment. The assumption is that formal elements are observable aspects of the art product that allow reliable and valid assessment of clients’ mental health. Most of the existing art therapy assessment instruments are based on clinical expertise. Therefore, it is not clear to what degree these instruments are restricted to formal elements. Other aspects might also be included, such as clinical expertise of the therapist. This raises the question of whether and how formal elements as observable aspects of the art product are related to clients’ mental health. To answer this question, four studies are presented that look at: (1) a meta-theoretical description of formal elements; (2) operationalization of these formal elements so they can be analyzed reliably in clients’ art products; (3) establishment of reliable and clinically relevant formal elements; (4) the relationship between formal elements and adult clients’ mental health. Results show that the combination of the formal elements “movement,” “dynamic,” and “contour” are significantly interrelated and related to clients’ mental health, i.e., psychopathology, psychological flexibility, experiential avoidance, and adaptability. These findings give insight in the diagnostic value of art products and how they may add to clients’ verbal expression and indicate their potential to benefit from therapy.
Abstract Background: To address the lack of social interaction and meaningful activities for persons with dementia (PWD) in nursing homes an artistic Photo-Activity was designed. The present study aims to develop a digital version of the Photo-Activity and to investigate its implementation and impact on nursing home residents with advanced dementia, and their (in)formal carers. Methods: First, within a user-participatory design, a digital-app version of the Photo-Activity will be developed and pilot-tested, in co-creation with (in)formal carers and PWD. Next, the feasibility and effectiveness of the Photo-Activity versus a control activity will be explored in a randomized controlled trial with nursing home residents (N=90), and their (in)formal carers. Residents will be offered the Photo- Activity or the control activity by (in)formal carers during one month. Measurements will be conducted by independent assessors at baseline (T0), after one month (T1) and at follow up, two weeks after T1 (T2). Qualitative and quantitative methods will be used to investigate the effects of the intervention on mood, social interaction and quality of life of the PWD, sense of competence of informal carers, empathy and personal attitude of the formal carers, and quality of the relationship between the PWD, and their (in)formal carers. In addition, a process evaluation will be carried out by means of semi-structured interviews with the participating residents and (in)formal carers. Finally, an implementation package based on the process evaluation will be developed, allowing the scaling up of the intervention to other care institutions. Discussion: Results of the trial will be available for dissemination by Spring 2023. The digital Photo-Activity is expected to promote meaningful connections between the resident with dementia, and their (in)formal carers through the facilitation of person-centered conversations. Trial registration: Netherlands Trial Register: NL9219; registered (21 January 2021); NTR (trialregister.nl)
