368 research outputs found
De IJzer: inventaris van de waterverontreiniging in het stroomgebied van de IJzer
The study of the pollution of the Yzer (West Flanders, Belgium) was created in the frame of the national programme for the physical and biological environment of the Interministrial Commission for Scientific Policy
ENDIS-RISKS: endocrine disruption in the Scheldt estuary - a field study
ENDIS-RISKS, a multidisciplinary research project with five institutes, evaluates the distribution, exposure and effects of endocrine disruptors in the Scheldt Estuary. This estuary is known to be one of the most polluted estuaries in the world. Untreated domestic wastewater and effluents of the industrial areas of Ghent and Antwerp are to a large extent responsible for this pollution. During an intensive field study of four years, eight sampling campaigns were executed on seven sampling points along the Scheldt Estuary. A detailed analysis of the distribution of endocrine disrupting substances in the Scheldt Estuary was executed. Water, sediment, suspended solids and biota were analysed for seven groups of chemicals: estrogens, pesticides, organotins, polyaromatic components, polyaromatic hydrocarbons and phenols. Special attention was given to the estuarine mysid shrimp Neomysis integer. Its ecotoxicology and population characteristics were studied in detail. A selection of results of this field study is put forward. Water samples, tested in vitro for their potential to bind with estrogen, revealed more estrogenic activity in the more upstream stations. Concentrations of chlorotriazine herbicides in water samples, were higher in the upstream reaches compared to the downstream sites. Analyses of TBT in mysid shrimps revealed high concentrations (>2mg.kg-1 dry weight) which suggests a high bioaccumulation capacity. Population characteristics results of N. integer show that it has a broader distribution range, with a shift more upstream, in comparison with historical data (Mees et al., 1995). On the other hand, length distribution of developmental stages of N. integer along the estuary indicates some environmental stress, caused by the estuarine gradient or by pollutants. Some hypotheses will be put forward to explain these patterns
Treatment with somatostatin analogues and prrt in metastatic middle ear adenoma with neuroendocrine features
SUMMARY: Middle ear adenomas with neuroendocrine features (ANEF) are rare, with an estimated 150 reported cases. They usually pursue an indolent clinical course. Four reported cases of middle ear ANEF with distant metastases were treated with surgery, external beam radiation therapy (EBRT) and chemotherapy. To date, no successful systemic treatment for malignant behaviour of this rare tumour has been reported. Long-acting somatostatin analogues (SSAs) and peptide receptor radionuclide therapy (PRRT) have been used in well-differentiated metastatic neuroendocrine tumours (NETs), but their use has never been described in cases of metastatic middle ear ANEF. We report two patients with grade 1 middle ear ANEF treated with surgery and EBRT. They had stable disease for several years, until clinical symptoms appeared and extensive metastases were detected on (68)Ga-DOTA(0)-Tyr(3)-octreotate (DOTATATE) PET/CT. Treatment with long-acting SSA was started, with stable disease for 1 year. Afterwards, despite undergoing local treatments, both patients presented progressive disease. Due to high-uptake metastases at (68)Ga-DOTATATE PET/CT, both cases underwent four cycles of PRRT with (177)Lu-DOTATATE, which secured disease control and improvement of quality of life in both. Similar to other well-differentiated NETs, SSA and PRRT could constitute efficacious therapeutic options in metastatic middle ear ANEF. Its neuroendocrine differentiation, potential to metastasize and somatostatin receptor type 2 expression prompt consideration and management of this disease as a neuroendocrine neoplasm. LEARNING POINTS: Our cases oppose the 2017 WHO classification of middle ear adenoma with neuroendocrine features as a benign disease. This entity warrants long-term follow-up, as local recurrence or persistence of disease is reported in up to 18% of surgically treated patients. PET/CT scan with (68)Ga-labelled somatostatin analogues (SSA) can be used for staging of metastatic middle ear adenoma with neuroendocrine features. Unlabelled SSA and peptide receptor radionuclide therapy (PRRT) with radiolabelled SSA can be the first systemic therapeutic options for patients with advanced middle ear adenoma with neuroendocrine features
Additional treatment after primary conservative treatment in patients with chronic subdural hematoma—A retrospective study
Objective: Chronic subdural hematoma (CSDH) is a common neurological condition and is typically treated with burr hole craniostomy. Nevertheless, conservative treatment may lead to spontaneous hematoma resolution in some patients. This study aims to describe the characteristics of patients who were treated conservatively without the eventual need for additional treatment. Methods: Data were retrospectively collected from patients who were primarily treated conservatively in three hospitals in the Netherlands from 2008 to 2018. The Primary outcome was the nonnecessity of additional treatment within 3 months after the initial CSDH diagnosis. We used univariable and multivariable logistic regression analyses to identify factors associated with not receiving additional treatment. Results: In this study, 83 patients were included and 61 patients (73%) did not receive additional treatment within 3 months. Upon first presentation, the patients had a Markwalder Grading Scale score (MGS) of 0 (n = 5, 6%), 1 (n = 43, 52%), and 2 (n = 35, 42%). Additional treatment was less often received by patients with smaller hematoma volumes (adjusted odds ratio [aOR] 0.78 per 10 mL; 95% confidence interval [CI] 0.64–0.92). Patients using antithrombotic medication also received less additional treatment, but this association was not significant (aOR 2.02; 95% CI 0.61–6.69). Conclusions: Three quarters of the initially conservatively treated CSDH patients do not receive additional management. Typically, these patients have smaller hematoma volumes. Further, prospective research is needed to distinguish which patients require surgical intervention and in whom primary conservative treatment suffices
A hybrid integration strategy for compact, broadband, and highly efficient millimeter-wave on-chip antennas
A novel hybrid integration strategy for compact, broadband, and highly efficient millimeter-wave (mmWave) on-chip antennas is demonstrated by realizing a hybrid on-chip antenna, operating in the [27.5-29.5] GHz band. A cavity-backed stacked patch antenna is implemented on a 600 mu m thick silicon substrate by using air-filled substrate-integrated-waveguide technology. A hybrid on-chip approach is adopted in which the antenna feed and an air-filled cavity are integrated on-chip, and the stacked patch configuration is implemented on a high-frequency printed circuit board (PCB) laminate that supports the chip. A prototype of the hybrid on-chip antenna is validated, demonstrating an impedance bandwidth of 3.7 GHz. In free-space conditions, a boresight gain of 7.3 dBi and a front-to-back ratio of 20.3 dB at 28.5GHz are achieved. Moreover, the antenna is fabricated using standard silicon fabrication techniques and features a total antenna efficiency above 90% in the targeted frequency band of operation. The high performance, in combination with the compact antenna footprint of 0.49 lambda(min) x 0.49 lambda(min), makes it an ideal building block to construct broadband antenna arrays with a broad steering range
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