1,361 research outputs found

    Self-assembled hexagonal double fishnets as negative index materials

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    We show experimentally the successful use of colloidal lithography for the fabrication of negative index metamaterials in the near-infrared wavelength range. In particular, we investigated a specific implementation of the widely studied double fishnet metamaterials, consisting of a gold-silica-gold layer stack perforated by a hexagonal array of round holes. Tuning of the hole diameter allows us to tailor these self-assembled metamaterials both as single- ({\epsilon} < 0) and double ({\epsilon} < 0 and {\mu} < 0) negative metamaterials

    Seculiere intolerantie: Morele progressiviteit en afwijzing van de islam in Nederland

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    Terwijl Nederland bekendstaat als baken van tolerantie, wordt er de laatste jaren opvallend veel kritiek geuit op de islam. Bovendien hanteren islamkritische opinie- leiders hierbij een discours waarbij progressieve waarden centraal staan. Dit roept de vraag op hoe morele progressiviteit en afwijzing van de islam met elkaar verbon- den zijn onder de bredere bevolking. En hoe verhoudt een op progressieve waarden gebaseerde verwerping van de islam zich tot

    Burgers op afstand? Naar een beter begrip van ontevreden burgers

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    Veel beschouwingen over de politiek in het algemeen en de vermeende kloof tussen de burger en de politiek in het bijzonder richten zich op ‘de ontevreden burger’. Ontevredenheid wordt daarbij op verschillende manieren ingevuld, variërend van zich niet vertegenwoordigd of gehoord voelen tot wantrouwen in instituties als de politiek en de rechtspraak, en steun aan populistische partijen. Maar wie zijn die ontevreden burgers, en waarom zijn zij zo ontevreden

    Impact of hormonal biomarkers on response to hormonal therapy in advanced and recurrent endometrial cancer

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    Inhibidores de la aromatasa; Terapia de progestinaAromatase inhibitors; Progestin therapyInhibidors de l'aromatasa; Teràpia amb progestinaBackground Approximately 20% of women with endometrial cancer have advanced-stage disease or suffer from a recurrence. For these women, prognosis is poor, and palliative treatment options include hormonal therapy and chemotherapy. Lack of predictive biomarkers and suboptimal use of existing markers for response to hormonal therapy have resulted in overall limited efficacy. Objective This study aimed to improve the efficacy of hormonal therapy by relating immunohistochemical expression of estrogen and progesterone receptors and estrogen receptor pathway activity scores to response to hormonal therapy. Study Design Patients with advanced or recurrent endometrial cancer and available biopsies taken before the start of hormonal therapy were identified in 16 centers within the European Network for Individualized Treatment in Endometrial Cancer and the Dutch Gynecologic Oncology Group. Tumor tissue was analyzed for estrogen and progesterone receptor expressions and estrogen receptor pathway activity using a quantitative polymerase chain reaction–based messenger RNA model to measure the activity of estrogen receptor–related target genes in tumor RNA. The primary endpoint was response rate defined as complete and partial response using the Response Evaluation Criteria in Solid Tumors. The secondary endpoints were clinical benefit rate and progression-free survival. Results Pretreatment biopsies with sufficient endometrial cancer tissue and complete response evaluation were available in 81 of 105 eligible cases. Here, 22 of 81 patients (27.2%) with a response had estrogen and progesterone receptor expressions of >50%, resulting in a response rate of 32.3% (95% confidence interval, 20.9–43.7) for an estrogen receptor expression of >50% and 50.0% (95% confidence interval, 35.2–64.8) for a progesterone receptor expression of >50%. Clinical benefit rate was 56.9% for an estrogen receptor expression of >50% (95% confidence interval, 44.9–68.9) and 75.0% (95% confidence interval, 62.2–87.8) for a progesterone receptor expression of >50%. The application of the estrogen receptor pathway test to cases with a progesterone receptor expression of >50% resulted in a response rate of 57.6% (95% confidence interval, 42.1–73.1). After 2 years of follow-up, 34.3% of cases (95% confidence interval, 20–48) with a progesterone receptor expression of >50% and 35.8% of cases (95% confidence interval, 20–52) with an estrogen receptor pathway activity score of >15 had not progressed. Conclusion The prediction of response to hormonal treatment in endometrial cancer improves substantially with a 50% cutoff level for progesterone receptor immunohistochemical expression and by applying a sequential test algorithm using progesterone receptor immunohistochemical expression and estrogen receptor pathway activity scores. However, results need to be validated in the prospective Prediction of Response to Hormonal Therapy in Advanced and Recurrent Endometrial Cancer (PROMOTE) study

    Ontevreden burgers serieus nemen

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    De laatste decennia is er onder politici en beleidsmakers veel aandacht voor ‘ontevreden’, ‘boze’ of ‘bezorgde’ burgers. Maar een goed begrip van hun boosheid blijft vooralsnog achterwege. In deze bijdrage stellen de auteurs dat dit kan veranderen door het perspectief en de belevingswereld van ontevreden burgers serieus te nemen

    Petrology, diagenesis amd reservoir potential of Narrabeen group sandstones, Sydney Basin, N.S.W.

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    ObjectivesTranscutaneous electrical neurostimulation (TENS) and spinal cord stimulation have been shown to increase peripheral and cerebral blood flow. We postulate that certain pathological conditions attenuate cerebral autoregulation, which may result in a relative increase of the importance of neurogenic regulation of cerebral blood flow, which could be decreased by electrical modulation. We therefore assess the effects of TENS on cerebral blood flow velocities (CBFVs) and cerebral saturation in patients with cerebral vasospasm after subarachnoid hemorrhage (SAH). Materials and MethodsCervical TENS was applied in 10 SAH patients with transcranial Doppler (TCD)-proven cerebral vasospasm. Measurements included plethysmography, near-infrared spectroscopy, capnography, and CBFVs by TCD. After determining the optimal frequency and current, patients were treated with cervical TENS for two periods of three days, with a pause of one day in between. ResultsThe TENS electrodes were not always tolerated by the patients. Higher frequencies demonstrated the most prominent combined effects. ETCO2 was 0.19% lower with TENS off than with TENS on (p = 0.05). Mean arterial blood pressure and pulse were not significantly different over time. CBFV in MCA was decreased (p = 0.07) while cerebral oxygen saturation was increased (p = 0.01) after the use of TENS. ConclusionsOur data suggest improved cerebral blood flow when using cervical TENS in patients with cerebral vasospasm. Several factors could have attenuated the effects: the electrodes were poorly tolerated, ETCO2 increased during TENS, few vessels showed prolonged vasospasm, and overall flow velocities were low. Still, an on-off effect of TENS over time was detected
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