Ashes for organic farming

Nowadays only eight percent of the cultivated field area is used for organic farming. The Ministry of Agriculture and Forestry has published the guidelines for the program of organic farming to diversify the supply and the consumption of organic food. The aim is to increase organically arable land to 20% by the year 2020.The demand of organic fertilizer products is strongly increasing. Interest in forestry by-products (ash, bark, zero fiber, etc.) for use in organic production has recently been exceptionally high. For example, development of pelleted fertilizers with zero fiber, ash and a nitrogen-containing fertilizer material is in progress.The ash fertilizer contains many valuable nutrients in fairly optimal ratios: these include phosphorus, potassium, manganese, magnesium, sulfur, zinc, calcium, boron, cobalt, copper and smaller amounts of other trace elements. Ashes contain phosphorus in large amounts, which is useful in organic production. More important nutrients than phosphorus and potassium are apparently trace elements. Neutralizing value of the ash is quite rapid comparedto many liming materials allowed in organic farming. The price quality ratio of ash as a liming material is also good.The use of clean wood ash is permissible in organic production. Peat and straw ash cannot be used in organic production because of the fact that in the EU peat is not considered a renewable resource. Restrictions include only inputs from outside of the organic farm

Instability and wavelength selection during step flow growth of metal surfaces vicinal to fcc(001)

We study the onset and development of ledge instabilities during growth of vicinal metal surfaces using kinetic Monte Carlo simulations. We observe the formation of periodic patterns at [110] close packed step edges on surfaces vicinal to fcc(001) under realistic molecular beam epitaxy conditions. The corresponding wavelength and its temperature dependence are studied by monitoring the autocorrelation function for step edge position. Simulations suggest that the ledge instability on fcc(1,1,m) vicinal surfaces is controlled by the strong kink Ehrlich-Schwoebel barrier, with the wavelength determined by dimer nucleation at the step edge. Our results are in agreement with recent continuum theoretical predictions, and experiments on Cu(1,1,17) vicinal surfaces.Comment: 4 pages, 4 figures, RevTe

Long wavelength properties of phase field crystal models with second order dynamics

The phase field crystal (PFC) approach extends the notion of phase field models by describing the topology of the microscopic structure of a crystalline material. One of the consequences is that local variation of the interatomic distance creates an elastic excitation. The dynamics of these excitations poses a challenge: pure diffusive dynamics cannot describe relaxation of elastic stresses that happen through phonon emission. To this end, several different models with fast dynamics have been proposed. In this article we use the amplitude expansion of the PFC model to compare the recently proposed hydrodynamic PFC amplitude model with two simpler models with fast dynamics. We compare these different models analytically and numerically. The results suggest that in order to have proper relaxation of elastic excitations, the full hydrodynamical description of the PFC amplitudes is required.Comment: 10 pages, 7 figure

Re-evaluation of Rapakivi Petrogenesis: Source Constraints from the Hf Isotope Composition of Zircon in the Rapakivi Granites and Associated Mafic Rocks of Southern Finland

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End-of-life care pathway of head and neck cancer patients : single-institution experience

Studies on palliative care of head and neck cancer (HNC) patients are scarce although the affected patient population is quite large. To evaluate the role of a specialised palliative-care pathway of HNC patients. Data on all HNC patients who were treated at the Helsinki University Hospital Palliative Care Center during 1 year were retrospectively reviewed. The analysis comprised 60 patients (49 males; mean age 67 years; range 28-88). All patients had a minimum follow-up of 1 year or until death. Fifty-nine (98%) out of the 60 patients died during the follow-up period. Median survival after diagnosis was 11 months (range 3 weeks-11.9 years) and after withholding disease-specific therapies 3 months (range 0-16). Thirty-three (55%) patients received palliative radiotherapy, 27 (45%) had PEG tube and 17 (28%) tracheostomy. Thirty-seven (66%) patients visited an emergency department (ED) (median 1.3 visits; range 0-6) and 21 (35%) were hospitalised at the university hospital during the palliative period. The most common severe complications were infection (also the most common reason for ED visits and hospitalisation), bleeding (four massive airway bleedings with one death), delirium and airway obstruction (one emergency tracheostomy). Twelve (35%) out of the 34 patients who were referred to specialised home care died at home as compared with three (12%) out of the 26 patients not supported by a specialised home-care team. Severe complications leading to an emergency unit visit and hospitalisation are common among HNC patients in their relatively short palliative period reflecting the need for early-integrated palliative care. Collaboration with a specialised palliative home-care team seems to increase end-of-life care at home.Peer reviewe

End-of-life care pathway of head and neck cancer patients : single-institution experience

Studies on palliative care of head and neck cancer (HNC) patients are scarce although the affected patient population is quite large. To evaluate the role of a specialised palliative-care pathway of HNC patients. Data on all HNC patients who were treated at the Helsinki University Hospital Palliative Care Center during 1 year were retrospectively reviewed. The analysis comprised 60 patients (49 males; mean age 67 years; range 28-88). All patients had a minimum follow-up of 1 year or until death. Fifty-nine (98%) out of the 60 patients died during the follow-up period. Median survival after diagnosis was 11 months (range 3 weeks-11.9 years) and after withholding disease-specific therapies 3 months (range 0-16). Thirty-three (55%) patients received palliative radiotherapy, 27 (45%) had PEG tube and 17 (28%) tracheostomy. Thirty-seven (66%) patients visited an emergency department (ED) (median 1.3 visits; range 0-6) and 21 (35%) were hospitalised at the university hospital during the palliative period. The most common severe complications were infection (also the most common reason for ED visits and hospitalisation), bleeding (four massive airway bleedings with one death), delirium and airway obstruction (one emergency tracheostomy). Twelve (35%) out of the 34 patients who were referred to specialised home care died at home as compared with three (12%) out of the 26 patients not supported by a specialised home-care team. Severe complications leading to an emergency unit visit and hospitalisation are common among HNC patients in their relatively short palliative period reflecting the need for early-integrated palliative care. Collaboration with a specialised palliative home-care team seems to increase end-of-life care at home.Peer reviewe