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Bistable unsymmetrical laminates have received significant attention in morphing applications due to their ability to attain multiple shapes when subjected to thermal loads. Morphing structures in general are subjected to dynamic operating conditions. Also, the highly nonlinear snap-through transition between stable configurations possesses rich dynamic characteristics. Therefore, understanding the dynamic characteristics of bistable laminates is essential for designing morphing structures constituting bistable elements. Thus, the present study aims to explore the dynamics of bistable unsymmetrical laminates by evaluating their natural vibration characteristics associated with small-amplitude dynamic excitation around the static equilibrium configurations. A refined semi-analytical framework is proposed to analyze the natural vibration characteristics of the bistable laminate, where the potential energy is expressed only in terms of the unknown coefficients of the assumed out-of-plane displacement function. The in-plane components are separately evaluated using the in-plane equilibrium equations and compatibility conditions. In the dynamic analysis, perturbations are imposed on the static equilibrium configurations to capture the modal characteristics. A full geometrically nonlinear finite element (FE) model of the bistable laminate has been created in a commercially available FE package to compare semi-analytical solutions. To validate the proposed frameworks, an experimental strategy to capture the natural frequencies of a bistable laminate is presented in this paper. Unsymmetric laminates mounted at its center have been used for the experimental testing, where the vibrations are measured using miniature integrated electronics piezoelectric accelerometer sensors attached at the corners. The semi-analytical and FE results are validated against the experimental observations for the selected unsymmetrical cross-ply laminates. The proposed frameworks are further extended to a family of unsymmetrical variable-stiffness (VS) laminates generated using curvilinear fiber alignments. The selected VS family can generate bistable shapes without any twisting curvature similar to that of an unsymmetrical cross-ply laminate, where the designer can expand the design space with a plethora of multiple configurations. A parametric study is performed by tailoring the VS parameters to investigate the influence of curvilinear fiber alignments on the natural vibration characteristics of bistable VS laminates.

Objective: The aim of this study is to examine the impact of opening a medical psychiatric unit (MPU) on a variety of outcomes. Methods: In this non-equivalent groups design, there were two groups: ‘pre-MPU’ and ‘actual MPU’. Staff assessed whether patients in the pre-MPU group were eligible for admission to a planned MPU, resulting in virtual admissions and discharges. The actual MPU group consisted of patients admitted after opening of the MPU. Results: The length of stay (LOS) in the hospital was one day longer for patients in the MPU group (8.68 vs. 9.89, p =.004), but the LOS on the MPU was comparable in both groups (5.63 vs. 6.06, p =.231). The LOS on the intensive care unit (ICU) was longer in the MPU group (0.10 vs. 0.40, p

Objective To study the course of the functional status and healthcare needs of patients on a Medical Psychiatric Unit (MPU). Methods In a single-centre observational prospective design the Health of the Nation Outcome Scales (HoNOS) and Camberwell Assessment of Needs Short Appraisal Schedule (CANSAS) instruments were administered at admission and discharge. Functional status and healthcare needs were assessed utilizing the HoNOS and CANSAS respectively. The total costs of healthcare claims related to the admission were calculated based on claims data. Results In total 50 patients were included with a mean improvement of 4.6 on the HoNOS and an effect size of 0.6.The total number of unmet needs fell from 208 to 115. The median costs per decreased HoNOS point were €2.842 and €6.880 per unmet need. Discussion Many patients improved, but due to a large standard deviation at baseline and a low Cronbach's alpha, only 4 patients showed a reliable improvement on functional status. That substantial remission was achieved was shown by the decrease in unmet needs of 93 (44.7%) for the whole group. These observations support the implementation of MPUs, although more research is warranted to ensure cost-effectiveness.

Background Hospital inpatients often experience medical and psychiatric problems simultaneously. Although this implies a certain relationship between healthcare utilization and costs, this relationship has never been systematically reviewed. Objective The objective is to examine the extent to which medical-psychiatric comorbidities relate to health-economic outcomes in general and in different subgroups. If the relationship is significant, this would give additional reasons to facilitate the search for targeted and effective treatments for this complex population. Method A systematic review in Embase, Medline, Psycinfo, Cochrane, Web of Science and Google Scholar was performed up to August 2016 and included cross-references from included studies. Only peer-reviewed empirical studies examining the impact of inpatient medical-psychiatric comorbidities on three health-economic outcomes (length of stay (LOS), medical costs and rehospitalizations) were included. Study design was not an exclusion criterion, there were no restrictions on publication dates and patients included had to be over 18 years. The examined populations consisted of inpatients with medical-psychiatric comorbidities and controls. The controls were inpatients without a comorbid medical or psychiatric disorder. Non-English studies were excluded. Results From electronic literature databases, 3165 extracted articles were scrutinized on the basis of title and abstract. This resulted in a full-text review of 86 articles: 52 unique studies were included. The review showed that the presence of medical-psychiatric comorbidity was related to increased LOS, higher medical costs and more rehospitalizations. The meta-analysis revealed that patients with comorbid depression had an increased mean LOS of 4.38 days compared to patients without comorbidity (95% CI: 3.07 to 5.68, I2 = 31%). Conclusions Medical-psychiatric comorbidity is related to increased LOS, medical costs and rehospitalization; this is also shown for specific subgroups. This study had some limitations; namely, that the studies were very heterogenetic and, in some cases, of poor quality in terms of risk of bias. Nevertheless, the findings remain valid and justify the search for targeted and effective interventions for this complex population.

Background Medical psychiatry units (MPU) provide integrated care for hospital patients with medical and psychiatric comorbidity. Lack of an empirically validated MPU typology hampers comparison of their (cost-)effectiveness. Methods A recent database on the organization of Dutch MPUs was used to empirically validate the MPU typology of Kathol (Model 1), develop types on the basis of the medical and psychiatric capabilities underlying this typology (Model 2), and to develop types from the data using k-means clustering (Model 3). Results Dutch MPUs are most alike the type III/IV MPUs described by Kathol. However, these types appear hardly distinctive for the Dutch context. The more generic approach of Model 2 provides comparable results. Both models show that the majority of Dutch MPUs handle moderate to high level medical and psychiatric acuity and can be classified as Complexity Intervention Units (CIUs). Model 3 yields three clusters to best characterize the Dutch field: CIUs with coercive admission facilities and 24/7 availability of ECT, CIUs without these facilities but with grossly comparable medical capabilities, and a smaller group of low acuity MPUs. Conclusions Kathol distinguished two types of CIUs (types III and IV MPUs) on the basis of medical acuity capabilities. This study reveals that psychiatric capabilities are most distinctive for the two high acuity MPU-types encountered in The Netherlands. In addition, a modest number of low acuity MPUs was found. Repeating our analysis in other countries is called for, as well as using the newly identified types for (cost)-effectiveness analysis in the Dutch context.

The ATLAS Collaboration will upgrade its semiconductor pixel tracking detector with a new Insertable B-layer (IBL) between the existing pixel detector and the vacuum pipe of the Large Hadron Collider. The extreme operating conditions at this location have necessitated the development of new radiation hard pixel sensor technologies and a new front-end readout chip, called the FE-I4. Planar pixel sensors and 3D pixel sensors have been investigated to equip this new pixel layer, and prototype modules using the FE-I4A have been fabricated and characterized using 120 GeV pions at the CERN SPS and 4 GeV positrons at DESY, before and after module irradiation. Beam test results are presented, including charge collection efficiency, tracking efficiency and charge sharing., Comment: 45 pages, 30 figures, submitted to JINST