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Most lectures in the field of engineering are held in a traditional teacher-centred and frontal lecture format. This means that all students receive the identical information at the same pace without taking their individual skills, knowledges and competences into account. A didactic concept, that fosters an individual learning experience and digitally provides personalised learning materials for each student is Adaptive E-Learning. Within this paper the development of an Adaptive E-Leaning Environment in the course Engineering Design at Ruhr-University Bochum is presented.
Self-ratings of psychotic experiences might be biased by depressive symptoms.
Method
Data from a large naturalistic multicentre trial on depressed inpatients (n = 488) who were assessed on a biweekly basis until discharge were analyzed. Self-rated psychotic symptoms as assessed with the 90-Item Symptom Checklist (SCL-90) were correlated with the SCL-90 total score, the SCL-90 depression score, the Beck Depression Inventory (BDI), the Hamilton Depression Rating Scale 21 item (HAMD-21) total score, the Montgomery Åsberg Depression Rating Scale (MADRS) total score and the clinician-rated paranoid-hallucinatory score of the Association for Methodology and Documentation in Psychiatry (AMDP) scale.
Results
At discharge the SCL-90 psychosis score correlated highest with the SCL-90 depression score (0.78, P<0.001) and with the BDI total score (0.64, P<0.001). Moderate correlations were found for the MADRS (0.34, P<0.001), HAMD (0.37, P<0.001) and AMDP depression score (0.33, P<0.001). Only a weak correlation was found between the SCL-90 psychosis score and the AMDP paranoid-hallucinatory syndrome score (0.15, P<0.001). Linear regression showed that change in self-rated psychotic symptoms over the treatment course was best explained by a change in the SCL-90 depression score (P<0.001). The change in clinician-rated AMDP paranoid-hallucinatory score had lesser influence (P = 0.02).
Conclusions
In depressed patients self-rated psychotic symptoms correlate poorly with clinician-rated psychotic symptoms. Caution is warranted when interpreting results from epidemiological surveys using self-rated psychotic symptom questionnaires as indicators of psychotic symptoms. Depressive symptoms which are highly prevalent in the general population might influence such self-ratings.
Postoperative cognitive impairment is among the most common medical complications associated with surgical interventions – particularly in elderly patients. In our aging society, it is an urgent medical need to determine preoperative individual risk prediction to allow more accurate cost–benefit decisions prior to elective surgeries. So far, risk prediction is mainly based on clinical parameters. However, these parameters only give a rough estimate of the individual risk. At present, there are no molecular or neuroimaging biomarkers available to improve risk prediction and little is known about the etiology and pathophysiology of this clinical condition. In this short review, we summarize the current state of knowledge and briefly present the recently started BioCog project (Biomarker Development for Postoperative Cognitive Impairment in the Elderly), which is funded by the European Union. It is the goal of this research and development (R&D) project, which involves academic and industry partners throughout Europe, to deliver a multivariate algorithm based on clinical assessments as well as molecular and neuroimaging biomarkers to overcome the currently unsatisfying situation.
Salmonella spp. continue to be a leading cause of foodborne morbidity worldwide. To assess the risk of foodborne disease, current national regulatory schemes focus on prevalence estimates of Salmonella and other pathogens. The role of pathogen quantification as a risk management measure and its impact on public health is not well understood. To address this information gap, a quantitative risk assessment model was developed to evaluate the impact of pathogen enumeration strategies on public health after consumption of contaminated ground turkey in the USA. Public health impact was evaluated by using several dose–response models for high- and low-virulent strains to account for potential under- or overestimation of human health impacts. The model predicted 2705–21 099 illnesses that would result in 93–727 reported cases of salmonellosis. Sensitivity analysis predicted cooking an unthawed product at home as the riskiest consumption scenario and microbial concentration the most influential input on the incidence of human illnesses. Model results indicated that removing ground turkey lots exceeding contamination levels of 1 MPN/g and 1 MPN in 25 g would decrease the median number of illnesses by 86–94% and 99%, respectively. For a single production lot, contamination levels higher than 1 MPN/g would be needed to result in a reported case to public health officials. At contamination levels of 10 MPN/g, there would be a 13% chance of detecting an outbreak, and at 100 MPN/g, the likelihood of detecting an outbreak increases to 41%. Based on these model prediction results, risk management strategies should incorporate pathogen enumeration. This would have a direct impact on illness incidence linking public health outcomes with measurable food safety objectives.
A 1995 surge of Variegated Glacier, Alaska, USA, is discussed in the context of its six 20th-century predecessors, especially the previous surge in 1982/83 which was studied in detail. The average time between surge initiations is 15 years. The 1995 surge was considerably weaker than its predecessors, having a single phase or at most a very weak second phase. The 1995 surge confirms that there is a seasonal cycle, with surge initiation in winter and termination in the first part of the melt season, and a correlation between weather and both surge termination date and surge extent. Two days of record high temperature correlated with the termination of the 1995 surge. The most obvious issue is the absence of a strong second surge phase (as there was in the 1982/83 surge) culminating in a surge extent more in line with that of the predecessors. This is considered in the light of a simple criterion for surge initiation and re-initiation which depends upon the evolving basal shear stress.
The last interglacial, commonly understood as an interval with climate as warm or warmer than today, is represented by marine isotope stage (MIS) 5e, which is a proxy record of low global ice volume and high sea level. It is arbitrarily dated to begin at approximately 130,000 yr B.P. and end at 116,000 yr B.P. with the onset of the early glacial unit MIS 5d. The age of the stage is determined by correlation to uranium–thorium dates of raised coral reefs. The most detailed proxy record of interglacial climate is found in the Vostok ice core where the temperature reached current levels 132,000 yr ago and continued rising for another two millennia. Approximately 127,000 yr ago the Eemian mixed forests were established in Europe. They developed through a characteristic succession of tree species, probably surviving well into the early glacial stage in southern parts of Europe. After ca. 115,000 yr ago, open vegetation replaced forests in northwestern Europe and the proportion of conifers increased significantly farther south. Air temperature at Vostok dropped sharply. Pulses of cold water affected the northern North Atlantic already in late MIS 5e, but the central North Atlantic remained warm throughout most of MIS 5d. Model results show that the sea surface in the eastern tropical Pacific warmed when the ice grew and sea level dropped. The essentially interglacial conditions in southwestern Europe remained unaffected by ice buildup until late MIS 5d when the forests disappeared abruptly and cold water invaded the central North Atlantic ca. 107,000 yr ago.
The prevalence of overweight and obesity is increasing worldwide. The impact of overweight on post-tonsillectomy haemorrhage rates in children and adults is unclear.
Methods:
Body mass index and post-tonsillectomy haemorrhage were evaluated in all patients treated with tonsillectomy within one year in a tertiary referral centre. Bleeding episodes were categorised according to the Austrian Tonsil Study.
Results:
Between June 2011 and June 2012, 300 adults and children underwent tonsillectomy. Post-tonsillectomy haemorrhage occurred in 55 patients. Of those, 29 were type A (history of blood in saliva only, no active bleeding), 15 were type B (active bleeding, treatment under local anaesthesia) and 11 were type C (active bleeding, treatment under general anaesthesia). The return to operating theatre rate was 3.7 per cent. Post-tonsillectomy haemorrhage was more frequent in adolescents and adults than in children. Overweight or obesity was positively correlated with age. Post-tonsillectomy bleeding was recorded in 11.1 per cent of underweight patients, 18.9 per cent of normal weight patients and 18.7 per cent of overweight patients (p = 0.7). Data stratification (according to age and weight) did not alter the post-tonsillectomy bleeding risk (p = 0.8).
Conclusion:
Overweight or obesity did not increase the risk of post-tonsillectomy haemorrhage in either children or adults.
Genetic similarities among 46 strains of rats based on published data involving 93 samples and 28 biochemical loci were assessed using principal coordinate and cluster analysis techniques. Seventeen strains were represented by more than one colony. In ten of these, nominally identical strains differed, and in four cases this was attributed to genetic contamination. A total of 52 genetically different strains were eventually identified. Strains BN and DA were most dissimilar, while strain BP was the most unusual strain over-all. The principal coordinate and cluster analysis showed three main clusters, which could be explained on the basis of linkage disequilibrium for some of the esterase loci in linkage group 5. Among six of these loci only 12 haplotypes were observed, with 24/52 strains having a single haplotype. Re-analysis of loci in linkage equilibrium failed to reveal any important clusters.
In its recently adopted Global Strategy on Infant and Young Child Feeding, the World Health Assembly called for urgent action in addressing the barriers to optimal feeding practices. This paper examines mothers’ concerns about milk insufficiency as a major contributor to suboptimal infant feeding decisions, using survey data from periurban areas of two Bolivian cities. Mothers in the lowland modernizing city of Santa Cruz were more likely than mothers in the highland traditional city of Cochabamba to express concern about insufficient milk, and also less likely to feed their infants according to international recommendations. Furthermore, perceived milk insufficiency was particularly common among mothers of infants younger than 6 months of age – an age at which infants are particularly vulnerable to the adverse effects of breast-feeding cessation and complementary feeding initiation. The paper concludes with policy, programme and research recommendations to address the critical problem of perceived insufficient breast milk.
Personality traits in euthymic elderly subjects with and without past histories of major depressive episodes were assessed using the Structured Clinical Interview for DSM-III-R and the Social Adjustment Scale-SR. Recovered depressed subjects were characterized by significantly more personality traits from DSM-III-R Clusters B and C than controls, and they exhibited differences in social adjustment, as well. Subjects who have recovered from depressive episodes may show significant diferences in personality and social adjustment that might represent residua of past depression, a trait characteristic, or a risk factor for recurrence.
Transparent electronics is an embryonic technology whose objective is the realization of invisible electronic circuits. We have recently reported the fabrication of a novel n-channel transparent thin-film transistor (TTFT). [1] This ZnO-based TTFT is highly transparent and exhibits electrical characteristics that appear to be suitable for implementation as a transparent select-transistor in each pixel of an active-matrix liquid-crystal display. Moreover, the processing technology used to fabricate this device is relatively simple and appears to be compatible with inexpensive glass substrate technology. The objective of the work reported herein is to summarize some of our recent TTFT electrical performance results. Materials, processing, and device structure details related to these devices appear in future publications.
The adhesion between several materials implemented in Cu/low-k integration is studied. Adhesion issues at different interfaces are important with regard to the reliability of back-end processing. Layered test structures are processed to study different interfaces. A tangential shear tester allows quantifying the adhesion force at the interface and provides a relative measurement to compare various materials. Failed interfaces are analyzed using auger electron spectroscopy (AES) and scanning electron microscopy (SEM). Among all studied structures, the strongest interface is seen between a barrier (Ti(N), Ta(N), WxN) and Cu. A weaker interface proves to be between a low-k dielectric and Cu. However, the presence of a barrier increases the adhesion. The weakest interface occurs between an oxide cap and the low-k material, with a lower adhesion when the low-k material is fluorinated. The low-k/cap oxide interface forms a critical issue with regard to Cu/low-k integration processing such as chemical mechanical polishing (CMP). All test structures show no significant degradation of the adhesion after a thermal cycle up to 400°C.
In this work, we will show that a reactive Ti capping layer can reduce oxide layers that are present at the cobalt-silicon interface. We have used a thin, chemically grown oxide to have a well-controlled form of interfacial oxide layer. To study the silicidation reaction, isochronal annealing was done at various temperatures. Different sets of samples were made in order to investigate the influence of the thickness of the Co layer and its Ti cap. Titanium capping strongly influenced the silicidation reaction. We have found that already at moderate temperatures, Ti can diffuse towards the Co/Si interface, and can reduce the interfacial oxide there present, enabling CoSi2 formation. The CoSi2 thus formed has a preferential epitaxial orientation, and the process by which this epitaxy is attained may be explained by a combination of OME (Oxide Mediated Epitaxy) and TIME (Titanium Mediated Epitaxy).
This paper reviews the results of clinical trials and community studies of lactational amenorrhoea and its role as a contraceptive method (LAM). Indicators which are used in efficacy trials and effectiveness interventions are compared and sets of indicators of effectiveness appropriate to community-based LAM programmes are recommended. A five-tiered ecological framework is used to facilitate selection of indicators which range from individual to policy level outcomes. The indicator framework is intended as a tool for health practitioners in family planning and maternal and child health service delivery settings who are interested in designing programmatic interventions for the promotion of LAM, particularly among less well-educated women of lower socioeconomic communities.
The Nd-disilicide, which exists only in a tetragonal or an orthorhombic structure, cannot be grown epitaxially on a Si(111) substrate. However, by adding Y and using channeled ion beam synthesis, hexagonal Nd0.32Y0.68Si1.7 epilayers with lattice constant of aepi = 0.3915 nm and cepi = 0.4152 nm and with good crystalline quality (χmin of Nd and Y is 3.5% and 4.3 % respectively) are formed in a Si(111) substrate. This shows that the addition of Y to the Nd-Si system forces the latter into a hexagonal structure. The epilayer is stable up to 950 °C; annealing at 1000 °C results in partial transformation into other phases. The formation, the structure and the thermal stability of this ternary silicide have been studied using Rutherford backscattering/channeling, x-ray diffraction and transmission electron microscopy.
Thin gadolinium silicide layers have been formed by channeled ion beam synthesis. Continuous and heteroepitaxial GdSil.7 layers with a hexagonal structure and a χmin value of 10% are prepared by Gd ion implantation at 90 keV to a dose of 1.3x1017/cm2 at 450°C in Si(111) using channeled implantation. The hexagonal phase of GdSi1.7 is stable up to a temperature of 850°C. Both the crystalline quality and the phase stability are much better than the results obtained by conventional techniques. Annealing at > 900°C suddenly changes the χmin value of the silicide layer from 10% to 100%. X-ray diffraction shows that the phase has changed to orthorhombic. RBS/channeling, x-ray diffraction and transmission electron microscopy are used in this study.
The results are discussed of the characterization by means of TEM, RBS and XRD of ErSi2-x layers prepared by ion beam synthesis on (111) silicon. It will be shown that high quality (buried) layers can be prepared by channelled implantation of the erbium, whereas unchannelled implantation leads to discontinuous polycrystalline surface layers. The epitaxial growth and vacancy ordering in the silicide are discussed.
An unusual Ni distribution with two completely separated buried and surface suicide layers has been observed after Ni ion implantation in Si(111) kept at a temperature of 300° C, with a dose of 1.1 × 1017/cm2 and at a fixed energy of 90 keV. RBS/channeling, AES and cross-sectional TEM have been used to study this phenomenon as a function of the substrate temperature and Co co4mplantation. A model is presented, based on the diffusion of the transition metal, the defect annealing during the implantation, and the gettering power of the surface and the end of range defects.