Acute heavy alcohol intake increases silent myocardial ischaemia in patients with stable angina pectoris

PURPOSE: The purpose was to determine tumor neovascularisation via colour-coded Doppler (duplex) sonography and the "power mode", both visually and quantitatively, by means of videodensitometry. MATERIAL AND METHODS: 6 VX2 tumours of 4 to 11 mm size were implanted in 4 rabbits at various sites. The colour-coded duplex sonography and the new sonographic power technique were tested before and after having injected a new contrast medium (SH U 616A). RESULTS: If no contrast medium was injected, tumour neovascularisation was identified in only 50% of the cases. Injection of contrast medium increased signal intensity three to fourfold with all examined tumors. Combined use of the sonographic method by the power technique with injection of contrast medium is outstandingly suitable for tumor vessel imaging even of small tumors, as these initial results seem to show. CONCLUSION: If these results are corroborated by further studies, contrast-medium supported sonographic technique may possibly become established as an alternative method to other imaging procedures.     

State-space solution to the periodic multirate H∞control problem: a lifting approach

A two-Riccati equation solution to the H_∞ control problem for periodic multirate systems is derived via the lifting method. The solution is expressed in terms of two algebraic Riccati equations. The causality constraints are represented by a set of positive definiteness conditions and coupling criteria. As a by-product, the study shows that there is a close connection between the solution of the causally constrained lifted problem and the solution obtained by solving the problem directly as a periodic H_∞ problem defined for the multirate system     

Effect of replacing grass silage with red clover silage on nutrient digestion,nitrogen metabolism,and milk fat composition in lactating cows fed diets containing a 60:40 forage-to-concentrate ratio

Diets based on red clover silage (RCS) typically increase the concentration of polyunsaturated fatty acids (PUFA) in ruminant meat and milk and lower the efficiency of N utilization compared with grass silages (GS). Four multiparous Finnish Ayrshire cows (108 d postpartum) fitted with rumen cannulas were used in a 4 × 4 Latin square design with 21-d periods to evaluate the effect of incremental replacement of GS with RCS on milk production, nutrient digestion, whole-body N metabolism, and milk fatty acid composition. Treatments comprised total mixed rations offered ad libitum, containing 600 g of forage/kg of diet dry matter (DM), with RCS replacing GS in ratios of 0:100, 33:67, 67:33, and 100:0 on a DM basis. Intake of DM and milk yield tended to be higher when RCS and GS were offered as a mixture than when fed alone. Forage species had no influence on the concentration or secretion of total milk fat, whereas replacing GS with RCS tended to decrease milk protein concentration and yield. Substitution of GS with RCS decreased linearly whole-tract apparent organic matter, fiber, and N digestion. Forage species had no effect on total nonammonia N at the omasum, whereas the flow of most AA at the omasum was higher for diets based on a mixture of forages. Replacing GS with RCS progressively lowered protein degradation in the rumen, increased linearly ruminal escape of dietary protein, and decreased linearly microbial protein synthesis. Incremental inclusion of RCS in the diet tended to lower whole-body N balance, increased linearly the proportion of dietary N excreted in feces and urine, and decreased linearly the utilization of dietary N for milk protein synthesis. Furthermore, replacing GS with RCS decreased linearly milk fat 4:0 to 8:0, 14:0, and 16:0 concentrations and increased linearly 18:2n-6 and 18:3n-3 concentrations, in the absence of changes in cis-9 18:1, cis-9, trans-11 18:2, or total trans fatty acid concentration. Inclusion of RCS in the diet progressively increased the apparent transfer of 18-carbon PUFA from the diet into milk, but had no effect on the amount of 18:2n-6 or 18:3n-3 at the omasum recovered in milk. In conclusion, forage species modified ruminal N metabolism, the flow of AA at the omasum, and whole-body N partitioning. A lower efficiency of N utilization for milk protein synthesis with RCS relative to GS was associated with decreased availability of AA for absorption, with some evidence of an imbalance in the supply of AA relative to requirements. Higher enrichment of PUFA in milk for diets based on RCS was related to an increased supply for absorption, with no indication that forage species substantially altered PUFA bioavailability.     

Examining the role of transformational leadership of portfolio managers in project performance

Research into the role of transformational leadership in project based organisations has generally focused on project managers or senior managers and less so on portfolio managers who oversee multiple projects to achieve business objectives. This study examines the impact of transformational leadership behaviour of portfolio managers on project performance directly and indirectly through other intervening variables such as climate for innovation and innovation championing. Using a questionnaire survey, data were obtained from 112 project managers in a UK project based organisation. Transformational leadership behaviour of portfolio managers was found to have a positive and significant relationship with project performance. Innovation championing and climate for innovation both partially mediated the relationship between transformational leadership and project performance. The study confirms the importance of portfolio managers in enhancing project performance and identifies the need for project based organisations to cultivate transformational leadership behaviour among them for enhanced performance. It also highlights the need for further exploration of the role of portfolio managers in improving project performance.     

The transformative effect of top management governance choices on project team identity and relationship with the organization — An agency and stewardship approach

This study focuses on the relationship and identity changes within and between a project team and its organization following top management intervention in the context of a large international construction project. The study follows the project-as-practice orientation, examining the actions and behaviors of the project team through participant ethnography in the “praxis” of the project site over its entire duration. The longitudinal case allows the examination of the way the transition process established a new governance culture undermining the initial trust-based one and changed it from a virtual absence of mechanisms toward far more potent mechanisms of control, monitoring, and punishment. Simultaneously, the initial stewardship relationships and collectivist identity of the project team shifted toward agency relationships and individualistic identity. The triggers for the transformation process were identified as CEO succession, project failure, top management intervention driven changes in governance mechanisms, and perception of organizational betrayal of the project team.     

SymbolChat: A flexible picture-based communication platform for users with intellectual disabilities

Persons with intellectual disabilities benefit from participating in the modern information society, especially the World Wide Web, social media and Internet-mediated communication services. Although several computer-based prototypes and commercial systems have been introduced for accessible in-person communication, currently few applications and services exist to support synchronous remote communication for this user group. We introduce SymbolChat, a software platform that supports the creation of multimodal communication applications utilizing picture-based instant messaging. End users and their support personnel can customize the input and output features of the application based on their individual needs and abilities. The interaction is based on touchscreen input and speech output using speech synthesis technology. The SymbolChat platform was developed together with the prospective end users and practitioners in the field of special needs care.We evaluated the prototype application in a field study with nine users with varying degrees of intellectual and other disabilities. The results clearly indicate that the participants were able to express themselves in spontaneous communication using a large-scale picture-based vocabulary (around 2000 symbols) even without prior training in the use of symbols. This finding was supported in the constructive feedback gathered from professionals working in the area. We also successfully applied methodology from other settings, such as child-computer interaction to evaluate interaction in this challenging context.Overall, the results show that social inclusion for people with intellectual disabilities can be improved with customizable communication tools. The implemented communication platform forms a solid basis for further improvements and new communication services. In addition, we found that users with motor impairments would greatly benefit from alternative input and output methods for symbol browsing and selection.     

Preliminary reference levels in interventional cardiology

This article describes the European DIMOND approach to defining reference levels (RLs) for radiation doses delivered to patients during two types of invasive cardiology procedures, namely coronary angiography (CA) and percutaneous transluminal coronary angioplasty (PTCA). Representative centres of six European countries recorded patients' doses in terms of dose-area product (DAP), fluoroscopy time and number of radiographic exposures, using X-ray equipment that has been subject to constancy testing. In addition, a DAP trigger level for cardiac procedures which should alert the operator to possible skin injury, was set to 300 Gyxcm2. The estimation of maximum skin dose was recommended in the event that a DAP trigger level was likely to be exceeded. The proposed RLs for CA and PTCA were for DAP 45 Gyxcm2 and 75 Gyxcm2, for fluoroscopy time 7.5 min and 17 min and for number of frames 1250 and 1300, respectively. The proposed RLs should be considered as a first approach to help in the optimisation of these procedures. More studies are required to establish certain "tolerances" from the proposed levels taking into account the complexity of the procedure and the patient's size.     

Tilted-wing-induced stress distribution in epitaxial lateral overgrown GaN

Epitaxial lateral overgrowth (ELO) is one of the most extensively studied techniques used to improve the mismatched heteroepitaxy of GaN on sapphire (-Al₂O₃) substrates. In this method, a mask is first deposited over the GaN seed layer and parallel windows are opened along a specific direction in the mask. GaN is grown vertically at the window position and then grows laterally along the mask surface (wing region). The adjacent GaN regions will coalesce to form a continuous film if enough growth time is used. The impact of the ELO of GaN on sapphire substrates using a SiO₂ mask is measured with the white beam synchrotron X-ray topography technique. The topography results show that the crystal planes in the laterally overgrown regions (wings) are tilted. The maximum wing tilt is about 0.36° at a fill factor of 0.5 (fill factor measures the window width relative to the window width plus SiO₂ mask width). High-resolution micro-Raman spectroscopy stress-mapping measurements, using Ar⁺ 488-nm laser excitation, indicate that the GaN epilayer is under compressive stress, as is expected from the growth conditions. The measured average compressive stress is about 460 MPa. Furthermore, a wave-like stress field is observed in the ELO GaN epilayer. The wave valley (low compressive stress region) is usually located at the coalesced region between two adjacent wings. In general, these coalesced regions exhibit about 60 MPa lower compressive stress than the average stress in the ELO epilayer. Voids formed by the tilted wings at the coalesced region are regarded as a possible reason for the lower compressive stress in the coalesced region.