Mikromekaaninen oskillaattori

Tässä diplomityössä tutustuttiin kapasitiivisesti kytketyllä mikromekaanisella resonaattorilla stabiloidun sähkömekaanisen oskillaattorin teoriaan: resonaattorin mekaniikkaan ja vahvistimen elektroniikkaan. Esitetyn teorian pohjalta suunniteltiin ja rakennettiin sähkömekaaninen 500 kHz:n Pierce-oskillaattori. Prototyypin toiminta demonstroitiin mittauksin. Prototyypin mittauksissa todennettiin mikromekaanisen oskillaattorin värähtelytaajuuden ja -amplitudin riippuvuus resonaattorin biasjännitteestä; mittaustulokset olivat ennusteiden mukaiset. Oskillaattorin värähtelytarkkuutta kuvaava vaihekohina mitattiin tarkoitukseen suunnitellulla laitteistolla. Mitattu vaihekohina oli -123dBc@SkHz. Prototyypissä käytettiin palkkiresonaattoria, jonka epälineaarisuuden seurauksena oskillaattorin ulostulo oli säröytynyt. Työssä pohdittiin myös fysikaalisia rajoja palkkiresonaattoriin perustuvan mikromekaanisen oskillaattorin suorituskyvylle

Propensity score-matched analysis of oncological outcome between stent as bridge to surgery and emergency resection in patients with malignant left-sided colonic obstruction

Background: Although self-expandable metal stent (SEMS) placement as bridge to surgery (BTS) in patients with left-sided obstructing colonic cancer has shown promising short-term results, it is used infrequently owing to uncertainty about its oncological safety. This population study compared long-term oncological outcomes between emergency resection and SEMS placement as BTS.Methods: Through a national collaborative research project, long-term outcome data were collected for all patients who underwent resection for left-sided obstructing colonic cancer between 2009 and 2016 in 75 Dutch hospitals. Patients were identified from the Dutch Colorectal Audit database. SEMS as BTS was compared with emergency resection in the curative setting after 1: 2 propensity score matching.Results: Some 222 patients who had a stent placed were matched to 444 who underwent emergency resection. The overall SEMS-related perforation rate was 7.7 per cent (17 of 222). Three-year locoregional recurrence rates after SEMS insertion and emergency resection were 11-4 and 13.6 per cent (P= 0-457), disease-free survival rates were 58-8 and 52.6 per cent (P= 0-175), and overall survival rates were 74-0 and 68-3 per cent (P= 0.231), respectively. SEMS placement resulted in significantly fewer permanent stomas (23.9 versus 45.3 per cent; P < 0-001), especially in elderly patients (29.0 versus 57.9 per cent; P < 0-001). For patients in the SEMS group with or without perforation, 3-year locoregional recurrence rates were 18 and 11.0 per cent (P= 0.432), disease-free survival rates were 49 and 59.6 per cent (P= 0-717), and overall survival rates 61 and 75.1 per cent (P= 0.529), respectively.Conclusion: Overall, SEMS as BTS seems an oncologically safe alternative to emergency resection with fewer permanent stomas. Nevertheless, the risk of SEMS-related perforation, as well as permanent stoma, might influence shared decision-making for individual patients.Research into fetal development and medicin

Linseed essential oil - source of lipids as active ingredients for pharmaceuticals and nutraceuticals

Linseed - also known as flaxseed - is known for its beneficial effects on animal health attributed to its composition. Linseed comprises linoleic and ?-linolenic fatty acids, various dietary fibers and lignans, which are beneficial to health because they reduce the risk of cardiovascular diseases, as well as cancer, decreasing the levels of cholesterol and relaxing the smooth muscle cells in arteries increasing the blood flow. Essential fatty acids from flax participate in several metabolic processes of the cell, not only as structuring components of the cell membrane but also as storage lipids. Flax, being considered a functional food, can be consumed in a variety of ways, including seeds, oil or flour, contributing to basic nutrition. Several formulations containing flax are available on the market in the form of e.g. capsules and microencapsulated powders having potential as nutraceuticals. This paper revises the different lipid classes found in flaxseeds and their genomics. It also discusses the beneficial effects of flax and flaxseed oil and their biological advantages as ingredients in pharmaceuticals and in nutraceuticals products.The authors wish to acknowledge the financial support from the Portuguese Science and Technology Foundation, Ministry of Science and Education (FCT/MEC) through national funds, and co-financed by FEDER, under the Partnership Agreement PT2020 for the project M-ERA-NET/0004/2015-PAIRED.info:eu-repo/semantics/publishedVersio