Inleiding tot die belangrikste metodes in die moderne literatuurwetenskap - 'n Metodologiese benadering

The article opens with a brief discussion of the development of literary theory as an independent discipline in the twentieth century. The author then provides some theoretical background and discussion of two main streams of modern literary method: Positivism and Hermeneutics

Embedded macrophages induce intravascular coagulation in 3D blood vessel-on-chip

Macrophages are innate immune cells that prevent infections and help in wound healing and vascular inflammation. While these cells are natural helper cells, they also contribute to chronic diseases, e.g., by infiltrating the endothelial layer in early atherosclerosis and by promoting vascular inflammation. There is a crosstalk between inflammatory pathways and key players in thrombosis, such as platelets and endothelial cells – a phenomenon known as ‘thromboinflammation’. The role of the embedded macrophages in thromboinflammation in the context of vascular disease is incompletely understood. Blood vessels-on-chips, which are microfluidic vascular cell culture models, have been used extensively to study aspects of vascular disease, like permeability, immune cell adhesion and thrombosis. Blood perfusion assays in blood vessel-on-chip models benefit from multiple unique aspects of the models, such as control of microvessel structure and well-defined flow patterns, as well as the ability to perform live imaging. However, due to their simplified nature, blood vessels-on-chip models have not yet been used to capture the complex cellular crosstalk that is important in thromboinflammation. Using induced pluripotent stem cell-derived endothelial cells and polarized THP-1 monocytes, we have developed and systematically set up a 3D blood vessel-on-chip with embedded (lipid-laden) macrophages, which is created using sequential cell seeding in viscous finger patterned collagen hydrogels. We have set up a human whole blood perfusion assay for these 3D blood vessels-on-chip. An increased deposition of fibrin in the blood vessel-on-chip models containing lipid-laden macrophages was observed. We anticipate the future use of this advanced vascular in vitro model in drug development for early atherosclerosis or aspects of other vascular diseases

The role of target closure in detachment in Magnum-PSI

A cylindrical target with a high degree of closure was exposed to ITER divertor-relevant plasmas with typical electron temperatures of 2 eV, electron densities of 5⋅1020 m−3, and heat fluxes up to 20 MWm−2 in the linear device Magnum-PSI. By terminating the plasma in an unpumped closed volume, neutral pressures were enhanced from about 0.5 to 20 Pa without any increase in the neutral flux returning to the plasma. Such pressures were sustained largely by the pressure exerted by the incoming plasma. By means of hydrogen gas injection, internal neutral pressures of up to 40 Pa were reached during plasma exposure. We find that at these high neutral pressures, a &lt; 1 eV recombination front forms and expands from the back of the cylinder, so that downstream density drops dramatically. Furthermore, in these scenarios, heat deposition to the back plate vanishes and is redirected to the upstream part of the cylinder and to hot neutrals, which can carry 50% of the plasma input power. A power balance analysis reveals that even without additional gas puffing, only about 10% of the incoming heat load reaches the back plate for the 20 MWm−2 plasma. These results demonstrate the important role of closed target configurations and local gas puffing in mitigating plasma heat loads and indicate that the gained experience should be taken into account in next-generation divertor designs.</p

Thermalized collisional pre-sheath detected in dense plasma with coherent and incoherent Thomson scattering

In the direct vicinity of plasma-facing surfaces, the incident plasma particles interact with surface-recombined neutrals. Remarkably high near-surface pressure losses were observed in the high-flux linear plasma generator Magnum-PSI. Combining the incoherent and coherent Thomson scattering diagnostics, we directly measured particle, momentum and energy fluxes down to 3 mm from the plasma target surface. At the surface, the particle and total heat flux were also measured, using respectively an in-target Langmuir probe and thermographic methods. The near-surface momentum and energy losses scale with density, and amount to at least 50 % and 20%, respectively, at ne=8centerdot1020m-3. These losses are attributed to the efficient exchange of charge, momentum and energy between incident plasma and surface-recombined neutrals. In low-temperature plasmas with sufficient density, incident particles go through several cycles of interaction and surface deposition before leaving the plasma, thereby providing an effective alternative dissipation channel to the incident plasma. Parallel plasma parameter profiles exhibit a transition with increasing plasma density. In low-density conditions, the plasma temperature is constant and near-surface ion acceleration is observed, attributed to the ambipolar electric field. Conversely, deceleration and plasma cooling are observed in dense conditions. These results are explained by the combined effect of ion-neutral friction and electron-ion thermal equilibration in the so-called thermalized collisional pre-sheath. The energy available for ambipolar acceleration is thus reduced, as well as the upstream flow velocity. In the ITER divertor, enhanced near-surface p-n interaction is expected as well, given the overlap in plasma conditions. Including these effects in finite-element scrape-off layer models requires a near-surface resolution smaller than the neutral mean free path. This amounts to 1 mm in Magnum-PSI, and possibly an order of magnitude smaller in ITER.</p

Exercise capacity in Dutch children

The Bruce treadmill protocol is suitable for children 4 years of age and older. Dutch reference values were established in 1987. We considered that children's exercise capacity has deteriorated due to changes in physical activity patterns and eating habits. We determined new reference values and evaluated determinants of exercise capacity. Healthy Dutch children (n=267) aged 6-13 years participated in this cross-sectional observational study. The maximal endurance time on the treadmill was the criterion of exercise capacity. Furthermore, we obtained data on anthropometry, smoking habits, socioeconomic status, ethnicity, sports participation, and school transport habits. The maximal endurance time for children aged up till 10 was lower (up to 1.6 and 1.4 min in girls and boys, respectively) than previously published. Body mass index was negatively, and intense sports participation was positively associated with endurance time (β=-0.412 and 0.789, respectively; P<0.001). In conclusion, exercise capacity seems to have deteriorated in Dutch children aged up till 10 years whereas the values from the older children are remarkably similar to those from the previous study

Cardiovascular disease risk in adults with spastic bilateral cerebral palsy

Objective: To explore: (i) cardiovascular disease risk factors and the 10-year clustered risk of a fatal cardiovascular event in adults with spastic bilateral cerebral palsy; and (ii) relationships between the 10-year risk and body fat, aerobic fitness and physical activity. Design: Cross-sectional study. Subjects: Forty-three adults with spastic bilateral cerebral palsy without severe cognitive impairment (mean age 36.6 years (standard deviation 6); 27 men). Methods: Biological and lifestyle-related risk factors and the 10-year risk according to the Systematic Coronary Risk Evaluation (SCORE) were assessed. Relationships were studied using multivariable linear regression analysis. Results: The following single risk factors were present: hypertension (n = 12), elevated total cholesterol (n = 3), low high-density lipoprotein cholesterol (n = 5; all men), high-risk waist circumference (n = 11), obesity (body mass index; n = 5; all men), reduced aerobic fitness (on average 80% of reference values), reduced level of everyday physical activity (on average 78% of reference values) and smoking (n=9). All participants had a 10-year risk <1%. Corrected for gender, participants with higher waist circumference (β = 0.28; p = 0.06) or body mass index (β=0.25; p = 0.08) tended to have a higher 10-year risk. Conclusion: In this relatively young adult sample of people with spastic bilateral cerebral palsy several single cardiovascular disease risk factors were present. The 10-year fatal cardiovascular disease risk was low, and higher body fat tended to be related to higher 10-year risk

Learn 2 Move 16-24: Effectiveness of an intervention to stimulate physical activity and improve physical fitness of adolescents and young adults with spastic cerebral palsy; a randomized controlled trial

Background: Persons with cerebral palsy (CP) are at risk for developing an inactive lifestyle and often have poor fitness levels, which may lead to secondary health complications and diminished participation and quality of life. However, persons with CP also tend not to receive structural treatment to improve physical activity and fitness in adolescence, which is precisely the period when adult physical activity patterns are established.Methods: We aim to include 60 adolescents and young adults (16-24 ye

Functional independence and health-related functional status following spinal cord injury: A prospective study of the association with physical capacity

Objective: To determine changes in functional independence following spinal cord injury and to evaluate the association between functional independence and physical capacity. Design: Multi-centre prospective cohort study. Subjects: Patients with spinal cord injury admitted for initial rehabilitation. Methods: The motor Functional Independence Measure (FIMmotor) was determined at the start of rehabilitation (n=176), 3 months later (n=124), at discharge (n=160) and one year after discharge from inpatient rehabilitation (n=133). One year after discharge, physical and social dimensions of health-related functional status (Sickness Impact Profile 68; SIP68) were determined. On each occasion, physical capacity was established by measuring arm muscle strength, peak power output and peak oxygen uptake. Results: Multi-level random coefficient analyses revealed that FIMmotor improved during inpatient rehabilitation, but stabilized thereafter. Changes in FIMmotor were associated with peak power output. Multiple regression models showed that FIMmotor and peak power output at discharge were associated with FIMmotor one year after discharge (R2=0.85), and that peak power output at discharge was associated with the social dimension of the SIP68 (R2=0.18) one year after discharge. Conclusion: Functional independence improves during inpatient rehabilitation, and functional independence is positively associated with peak power output