The Gaussian free field and Hadamard's variational formula

We relate the Gaussian free field on a planar domain to the variational formula of Hadamard which explains the change of the Green function under a perturbation of the domain. This is accomplished by means of a natural integral operator related to Hadamard's formula.Comment: 9 page

Weak compactness and essential norms of integration operators

Let $g$ be an analytic function on the unit disc and consider the integration operator of the form $T_g f(z) = \int_0^z fg'\,d\zeta$. We show that on the spaces $H^1$ and $BMOA$ the operator $T_g$ is weakly compact if and only if it is compact. In the case of $BMOA$ this answers a question of Siskakis and Zhao. More generally, we estimate the essential and weak essential norms of $T_g$ on $H^p$ and $BMOA$

Compact differences of composition operators on Bloch and Lipschitz spaces

Peer reviewe

Toiminnanohjausjärjestelmän valinta pk-yritykselle

Tässä opinnäytetyössä tutkittiin pk-yritykselle sopivia toiminannanohjausjärjestelmiä. Opinnäytetyön tarkoituksena oli selvittää, minkälaisia toiminnanohjausjärjestelmiä pienille ja keskisuurille yrityksille on saatavilla, ja ehdottaa yritykselle sopivinta järjestelmäratkaisua. Lisäksi työssä käsitellään toiminnanohjausjärjestelmän valintaan ja hankintaan liittyviä kysymyksiä. Työn toimeksiantajana toimi Saimaan ammattikorkeakoulun Tikli-projekti. Opinnäytetyössä on vertailtu ja tutkittu pk-yritykselle suunnattuja toiminnanohjausjärjestelmiä ja ehdotettu sopivinta vaihtoehtoa vastaamaan yrityksen nykyisiä liiketoimintaprosesseja. Työtä tehdessämme perehdyimme yrityksen toimintaan tekemällä yhteistyötä yrityksen yhteyshenkilön kanssa. Yhteyttä yrityksen kanssa pidettiin palaverien ja sähköpostin avulla. Tutkimuksen perusteella todettiin, että sopivia toiminnanohjausjärjestelmiä pk-yrityksille on vähän. Lisäksi tietojärjestelmän hankintaprosessi voi tuntua haastavalta yrityksille, joilla on käytössään vähän tietoteknillisiä valmiuksia. Opinnäytetyön lopputuloksena yrityksille ehdotettiin kahta toiminnanohjausjärjestelmää,jotka olivat Microsoftin Dynamics Navision ja yrityksen käytössä oleva Exceliin pohjautuva järjestelmä parannuksin

Cervical Cancer Screening Programme in Finland with an Example on Implementing Alternative Screening Methods

In Finland (population 5 million) the organised Pap screening programme for preventing cervical cancer has been in action already for 45 years. Women aged 30 to 64 are targeted (N 1.25 million) and the screening interval is five years. The programme invites women seven times in a lifetime; the attendance rate per one screening invitational round is 73%. The programme has affected markedly the cervical cancer rates in our country. During the decennia of its action there has been about 80% decrease in the age-adjusted cervical cancer incidence and mortality rates. The current age-standardised incidence rate is 4 and mortality rate 1 per 100,000 woman-years. In the current article we describe the organisational aspects of the programme; and pay attention to renovation of the programme taken place during the last decade when novel technological alternatives have been started to be used as the screening tests. By expanding the coverage and compliance of screening we still expect to increase the impact of the programme. Same time, efforts are needed to avoid overuse of services due to spontaneous screening, in order to decrease potential adverse effects and improve overall costeffectiveness. A large-scale public health policy trial on Human papillomavirus (HPV) screening is on-going. Cross-sectional information available thus far suggests promising results. Follow-up of cancer rates after screening episodes are still required to evaluate optimal screening policies (e.g., screening intervals by age groups, and starting and stopping ages). We propose speeding up the use of modern technological alternatives in organised screening programmes

On compactness of the difference of composition operators

Peer reviewe

Labile carbon addition affects soil organisms and N availability but not cellulose decomposition in clear-cut Norway spruce forests

We assessed the effects of sucrose addition on the biological and chemical properties of organic soil in clear-cut Norway spruce forests managed with or without wood-ash fertilization and mechanical site preparation. Sucrose addition increased the abundances of enchytraeids and tardigrades and soil moisture percentage in the clear-cut areas. Sucrose also increased nematode abundance in the non-fertilized plots. Sucrose reduced the pool of waterextractable NH4-N in the soil in the first year, but increased it in the second year. Sucrose addition did not affect the decomposition rate of cellulose strips. The biomass of ground vegetation was not affected by sucrose. Carbohydrate addition seems to enhance N immobilization in clear-cut areas in the short term, and it is suggested that aims at reducing N loss from disturbed forest soil do not necessarily accelerate carbon loss from the forest ecosystem.peerReviewe

On the connected component of compact composition operators on the Hardy space

We show that there exist non-compact composition operators in the connected component of the compact ones on the classical Hardy space $H^2$ on the unit disc. This answers a question posed by Shapiro and Sundberg in 1990. We also establish an improved version of a theorem of MacCluer, giving a lower bound for the essential norm of a difference of composition operators in terms of the angular derivatives of their symbols. As a main tool we use Aleksandrov-Clark measures.Comment: 16 page