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An extended modification phase of the superconducting fusion experiment Wendelstein 7-X (W7-X) was completed late 2021 after installing actively cooled divertor units and the integration or modification of new technical components and diagnostics. Currently, the commissioning of the W7-X experiment is underway. First, technical plasma operation is scheduled for the end of September 2022, and scientific plasma operation will start at the end of November. The fast interlock system (FIS) is an important component of the safety instrumented system (SIS) of W7-X. The main task of the FIS is to protect the inner plasma vessel components from thermal overload from both plasma heating systems (e.g., neutral beam injection) and the plasma itself. There are strict limits for reaction times after detection of interlock relevant events, which have to be observed in order to prevent overload situations of the first wall. The requirements for the FIS were substantially modified and extended, in order to address the challenges due to the actively cooled divertor. This led to extensive revision of the technical implementation and the software of the FIS. In this article, after a short introduction of FIS design and operation in operating phase (OP1), the modification of FIS for OP 2.1 operation is presented. Finally, the first results during the OP 2.1 commissioning and operation of the FIS are discussed.

AbstractObjective: Cervical cancer is the most common gynaecological cancer in South Africa, and the vast majority of women present with an advanced stage of the disease. This can be attributed to the absence of an implemented screening programme, resulting in patients becoming symptomatic prior to diagnosis. There are little data on the health-seeking behaviour of these women. The objective was to investigate the circumstances of patients who present with cervical cancer, as well as examine their presenting symptoms and behaviour following the onset of symptoms.Design: Descriptive study. Data were collected from patients who were diagnosed with cervical cancer by means interviews and a questionnaire.Setting and subjects: Women diagnosed and managed with cervical cancer at the Gynaecological Oncology Unit, Kalafong Hospital, Pretoria.Outcomes measured: Included demographic data, tumour characteristics, presenting symptoms, number of visits to and interventions performed at the primary healthcare contact.Results: Eighty-five patients were recruited. Of these, 74% lived in rural areas, 81% had access to primary healthcare facilities and 83% lived close to a healthcare provider. Eight had early-stage disease. The most common presenting symptoms were vaginal bleeding, pain and vaginal discharge. After the onset of symptoms, 55% of patients visited their healthcare provider within four weeks. At the first visit, only 41% of patients had a gynaecological examination and only 15% were appropriately referred, compared to 23% at their second visit. Late presentation was significantly associated with no gynaecological examination (p-value < 0.01).Conclusion: The lack of a cervical cancer screening programme, suboptimal management of symptomatic patients and low levels of literacy and knowledge about cervical cancer and screening are compounding the plight of these patients.

The main reasons for dimensional and geometric errors in workpieces produced on machine tools include low static stiffness of the machine structure, low dynamic performance of feed drives, tool wear and thermal deformations of the tool, machine and workpiece. This paper describes the latest research in analysing and reduction of thermally induced deformations in machine tools which lead to thermal drift displacements between tool and workpiece. A brief introduction to the problem is followed by an analysis of different heat sources and how they deformations. Attention is drawn to measures for reducing thermal drift as a mayor cause of errors in machine tools.

Recently measured anomalies in the high temperature resistivity of dilute alloys (transition metals in copper) are interpreted on the basis of the Anderson model. Assuming that the anomalies are caused by phonons the Anderson hamiltonian extended to the case of many impurities is treated, electron-phonon coupling being included. Using the equation-of-motion technique for theGreen's functions, the free electron relaxation time, and the resistivity are calculated. The approximations consist in neglecting impurity correlations and taking into account only terms linear in the temperature and the impurity concentration. We find that in most cases the calculated additional resistivity caused by the impurities show the measuredT-dependance as related to the occurrence of magnetic moments of the impurities in the host metal.