Direct response of twin-slot antenna-coupled hot-electron bolometer mixers designed for 2.5 THz radiation detection

We measure the direct response of a Nb diffusion-cooled hot-electron bolometer mixer in a frequency range between 0.5 and 3.5 THz. The mixer consists essentially of a twin-slot antenna, a co-planar waveguide transmission line and a Nb superconducting bridge. It is designed for use in receivers with astronomical and atmospherical applications around 2.5 THz. We calculate the impedance of the antenna, the transmission line, and the bridge separately using models which are developed for frequencies below 1 THz and predict the direct response of the mixer. We demonstrate that these models can be applied to much higher frequencies. However, the measured central frequency is 10%-15% lower than predicted. (C) 2000 American Institute of Physics. [S0003-6951(00)02022-2]

Self-ordered pointing and visual conditional associative learning tasks in drug-free schizophrenia spectrum disorder patients

<p>Abstract</p> <p>Background</p> <p>There is evidence of a link between schizophrenia and a deficit of working memory, but this has been derived from tasks not specifically developed to probe working memory per se. Our aim was to investigate whether working memory deficits may be detected across different paradigms using the self-ordered pointing task (SOPT) and the visual conditional associative learning task (VCALT) in patients with schizophrenia spectrum disorders and healthy controls. The current literature suggests deficits in schizophrenia spectrum disorder patients versus healthy controls but these studies frequently involved small samples, broad diagnostic criteria, inclusion of patients on antipsychotic medications, and were not controlled for symptom domains, severity of the disorder, etc. To overcome some of these limitations, we investigated the self-monitoring and conditional associative learning abilities of a numerically representative sample of healthy controls and a group of non-deteriorated, drug-free patients hospitalized for a schizophrenia spectrum disorder with florid, mainly positive psychotic symptoms.</p> <p>Methods</p> <p>Eighty-five patients with a schizophrenia spectrum disorder (DSM-IV-TR diagnosis of schizophrenia (<it>n </it>= 71) or schizophreniform disorder (<it>n </it>= 14)) and 80 healthy controls entered the study. The clinical picture was dominated by positive symptoms. The healthy control group had a negative personal and family history of schizophrenia or mood disorder and satisfied all the inclusion and exclusion criteria other than variables related to schizophrenia spectrum disorders.</p> <p>Results</p> <p>Compared to controls, patients had worse performances on SOPT, VCALT and higher SOPT/VCALT ratios, not affected by demographic or clinical variables. ROC curves showed that SOPT, VCALT, and SOPT/VCALT ratio had good accuracy in discriminating patients from controls. The SOPT and VCALT scores were inter-correlated in controls but not in patients.</p> <p>Conclusion</p> <p>The selection of a clinically homogeneous group of patients, controlled for a number of potential confounding factors, and the high level of significance found in the different analyses confirm the presence of SOPT and VCALT abnormalities in a large preponderance of patients with schizophrenia spectrum disorder with positive symptoms. SOPT, VCALT, and SOPT/VCALT ratio showed good accuracy in discriminating patients from healthy controls. These conclusions cannot be extended to schizophrenia spectrum disorder patients with a different clinical profile from our patient population.</p

Health problems and care needs in patients with Korsakoff’s syndrome: A systematic review

What is known on the subject?: Patients with Korsakoff's syndrome suffer from a broad range of comorbid somatic and/or psychiatric conditions. The various health problems in patients with Korsakoff's syndrome limit their ability to perform daily activities and also negatively affect their social functioning. What the paper adds to existing knowledge?: Patients with Korsakoff's syndrome have complex somatic and psychiatric comorbid conditions co-occurring with behavioural and functional problems. They are compounded by patients’ poor self-awareness regarding their health status and functioning. What are the implications for practice?: This review demonstrates that patients with Korsakoff's syndrome should receive integrated care. Integrated care for patients with Korsakoff's syndrome should be based on accurate multidimensional and multidisciplinary diagnostics in which nurses and nurse assistants have a prominent role due to their central position in the care process patients with Korsakoff's syndrome. Abstract: Introduction The literature shows that Korsakoff's syndrome is associated with a wide range of severe comorbid somatic and psychiatric health problems that lead to care needs in several domains of functioning. Aim To provide a comprehensive overview of Korsakoff patients’ health conditions and related care needs. Method Following the PRISMA guidelines, we searched MEDLINE, PsycInfo, Cochrane Library and CINAHL up to January 2019. After applying our inclusion criteria, two reviewers independently selected the studies, extracted the data and assessed methodological quality. Results Twelve articles were included. The commonest somatic comorbid conditions were liver disease, cardiovascular disease, COPD and diabetes mellitus. The commonest psychiatric comorbid conditions were mood disorder, personality disorder and psychotic disorder. Anxiety, aggressive/agitated behaviour, depressive symptoms and care needs in social functioning and (instrumental) activities of daily living were also very commonly reported. Discussion In patients with Korsakoff's syndrome, somatic and psychiatric comorbid conditions co-occur with behavioural and functional problems. They are compounded by patients’ poor self-awareness regarding their health status and functioning. Adequate responses to their care needs require high-quality integrated care. Implications for practice Patients with Korsakoff's syndrome should receive integrated care based on accurate multidimensional and multidisciplinary diagnostics in which nurses have a prominent role