Seed loss as a result of pod shatter in spring rape and spring turnip rape in Finland : Research Note

Selostus: Öljykasvien siementen variseminen ennen puintia

Regeneration process from seed crop to saplings : a case study in uneven-aged Norway spruce-dominated stands in southern Finland

Abstract

The health effects of sea buckthorn berries and oil

Sea buckthorn (Hippophaë) berries are ingredients of the Chinese traditional medicine. In addition to China, they are nowadays cultivated for food in several European countries, Russia, Canada, the USA, and Japan. Sea buckthorn berries are a rich source of flavonoids, mainly flavonol glycosides and proanthocyanidins. Depending on the genetic background, growth conditions, and ripeness of the berries, vitamin C concentrations up to over 1 g/100 ml juice, have been reported. Sea buckthorn berries contain inositols and methyl inositols, components of messenger molecules in humans. Sea buckthorn seed oil is rich in essential aplha-linolenic and linoleic acids, whereas the most abundant fatty acids in the berry oil are palmitoleic, palmitic and oleic acids. Other potentially beneficial lipophilic compounds of sea buckthorn seeds and berries include carotenoids, phytosterols, tocopherols and tocotrienols. The effects of sea buckthorn fractions on inflammation, platelet aggregation, oxidation injuries, the liver, skin and mucosa, among others, have been reported. The aim of the thesis work was to investigate the health effects of sea buckthorn berries and oil in humans. The physiological effects of sea buckthorn berries, berry components, and oil have mostly been studied in vitro and in animal models, leaving a demand for more clinical trials. In the first randomized, placebo-controlled trial of this thesis healthy adults consumed 28 g/day of sea buckthorn berries for three months. The main objective was to investigate the effects on the common cold. In addition, effects on other infections, inflammation and circulating lipid markers associated with cardiovascular disease risk were studied. In the second randomized, placebocontrolled trial participants reporting dry eye symptoms consumed 2 g/day of sea buckthorn oil from the seeds and berries for three months. The effects on symptoms and clinical signs of dry eye were monitored. In addition, the effects on circulating markers of inflammation and liver functions were analyzed. Sea buckthorn berries did not affect the common cold or other infections in healthy adults. However, a decrease in serum C-reactive protein was detected, indicating effects on inflammation. Fasting concentrations of serum flavonols, typical to sea buckthorn berry, increased without affecting the circulating total, HDL, LDL cholesterol, or triacylglycerol concentrations. Tear film hyperosmolarity and activation of inflammation at the ocular surface are among the core mechanisms of dry eye. Combined sea buckthorn berry and seed oil attenuated the rise in tear film osmolarity taking place during the cold season. It also positively affected some of the dry eye symptoms. Based on the tear film fatty acid analysis, the effects were not mediated through direct incorporation of sea buckthorn oil fatty acids to tear film lipids. It is likely that the fatty acids, carotenoids, tocopherols and tocotrienols of sea buckthorn oil affected the inflammation of the ocular surface, lacrimal and/or meibomian glands. The effects on the differentiation of meibomian gland cells are also possible. Sea buckthorn oil did not affect the serum concentrations of inflammation markers or liver enzymes investigated. In conclusion, this thesis work suggests positive effects of sea buckthorn berries and oil on inflammation and dry eye, respectively, in humans.

Blackcurrant seed oil for prevention of atopic dermatitis

One hypothesis for the increased incidence of atopic diseases has been that it is associated with changing dietary habits, especially the changed intake of essential fatty acids (EFAs). The metabolism of EFAs produces eiconasoids, prostaglandins and leukotrienes, which are essential to organs and play a major role in regulation of inflammation and immune response. In some studies persons with atopic dermatitis have been found to have reduced levels of EFAs. The first year of infancy as well as the foetal period are crucial for the development of atopic immune response. The composition of blackcurrant seed oil (BCSO) corresponds to the recommended ratio of EFAs n-3 and n-6 in the diet (1/3-1/4) and as a dietary supplement could, even in small doses, modify the unbalance of EFAs in an efficient way. The purpose of this study was to find out whether atopic allergies can be prevented by supplementing the diet of pregnant mothers with blackcurrant seed oil and whether it could affect the immunological balance of a child. We also sought to find out whether a blackcurrant seed oil supplementation can affect the composition of breast milk to suppress the T helper 2 lymphocyte (Th2) responses in infants. 313 pregnant mothers were randomly assigned to receive BCSO (n=151) or olive oil as placebo (n=162). Supplementation was started at the 8th to 16th weeks of pregnancy, 6 capsules per day (dose of 3 g), and continued until the cessation of breastfeeding. It was thereafter followed by direct supplementation to infants of 1 ml (1 g) of oil per day until the age of two years. Atopic dermatitis and its severity (SCORAD index) were evaluated, serum total IgE was measured and skin prick tests were performed at the age of 3, 12 and 24 months. Peripheral blood mononuclear cell (PBMC) samples were taken at the age of 3 and 12 months and breast milk samples were collected during the first 3 months of breastfeeding. Parental atopy was common (81.7%) in the studied infants, making them infants with increased atopy risk. There was a significantly lower prevalence of atopic dermatitis in the BCSO group (33%) than in the olive oil group (47%) at the age of 12 months. Also, SCORAD was lower in the BCSO group than in the olive oil group. Dietary intervention with BCSO had immunomodulatory effects on breast milk, inducing cytokine production from Th2 to Th1 immunodeviation. It decreased the level of IL-4 and elevated the level of IFN-γ. BCSO intervention did not affect cytokines in the children’s PBMC. However, children of smoking parents in the combined BCSO and olive oil group had significantly elevated levels of Th2 type cytokines IL-4, IL-5 and the proinflammator cytokine TNF. Dietary supplementation with BCSO is safe. It is well tolerated and transiently reduces the prevalence of atopic dermatitis at the age of 12 months. It can possibly become a potential tool in prevention of atopic symptoms when used at the early stages of life.

Differential evolution based classification with pool of distances and aggregation operators

The objective of this thesis is to develop and generalize further the differential evolution based data classification method. For many years, evolutionary algorithms have been successfully applied to many classification tasks. Evolution algorithms are population based, stochastic search algorithms that mimic natural selection and genetics. Differential evolution is an evolutionary algorithm that has gained popularity because of its simplicity and good observed performance. In this thesis a differential evolution classifier with pool of distances is proposed, demonstrated and initially evaluated. The differential evolution classifier is a nearest prototype vector based classifier that applies a global optimization algorithm, differential evolution, to determine the optimal values for all free parameters of the classifier model during the training phase of the classifier. The differential evolution classifier applies the individually optimized distance measure for each new data set to be classified is generalized to cover a pool of distances. Instead of optimizing a single distance measure for the given data set, the selection of the optimal distance measure from a predefined pool of alternative measures is attempted systematically and automatically. Furthermore, instead of only selecting the optimal distance measure from a set of alternatives, an attempt is made to optimize the values of the possible control parameters related with the selected distance measure. Specifically, a pool of alternative distance measures is first created and then the differential evolution algorithm is applied to select the optimal distance measure that yields the highest classification accuracy with the current data. After determining the optimal distance measures for the given data set together with their optimal parameters, all determined distance measures are aggregated to form a single total distance measure. The total distance measure is applied to the final classification decisions. The actual classification process is still based on the nearest prototype vector principle; a sample belongs to the class represented by the nearest prototype vector when measured with the optimized total distance measure. During the training process the differential evolution algorithm determines the optimal class vectors, selects optimal distance metrics, and determines the optimal values for the free parameters of each selected distance measure. The results obtained with the above method confirm that the choice of distance measure is one of the most crucial factors for obtaining higher classification accuracy. The results also demonstrate that it is possible to build a classifier that is able to select the optimal distance measure for the given data set automatically and systematically. After finding optimal distance measures together with optimal parameters from the particular distance measure results are then aggregated to form a total distance, which will be used to form the deviation between the class vectors and samples and thus classify the samples. This thesis also discusses two types of aggregation operators, namely, ordered weighted averaging (OWA) based multi-distances and generalized ordered weighted averaging (GOWA). These aggregation operators were applied in this work to the aggregation of the normalized distance values. The results demonstrate that a proper combination of aggregation operator and weight generation scheme play an important role in obtaining good classification accuracy. The main outcomes of the work are the six new generalized versions of previous method called differential evolution classifier. All these DE classifier demonstrated good results in the classification tasks.