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Sample records for heikkil juha laitila

  1. Longitudinal study of dental caries prevalence and incidence in the rapakivi (high fluoride) and olivine diabase (low fluoride) areas of Laitila, Finland.

    PubMed

    Pärkö, A

    1990-01-01

    This paper is a continuation of the author's study published in 1975. The teeth of the school children included in the study were first examined in 1952, re-examined in 1972 and subsequently at 5-year intervals. Children in the village of Salo had drinking water with a high fluride content and those in the village of Suontaka drank water with a low fluoride content. In the first examination, the Salo children showed a caries prevalence, measured with the DMF inxed, ca. 67% lower than the Suontaka children. With some exceptions, such as the first molars, the absolute differences in caries prevalence between subjects from the two villages had remained practically the same throughout the years. By the 1987 examination, the difference had been reduced, measured with the DMF index, to about 23% and with the DMFS index, to about 28%. In the last 5 years (1982-87), the DMFS index of the Suontaka pupils increased by 2.5 and that of the Salo pupils by 4.1. In the preceding two 5-year periods the increment in each group was ca. 7.0%.

  2. Longitudinal study of dental caries prevalence and incidence in the rapakivi (high fluoride) and olivine diabase (low fluoride) areas of Laitila, Finland.

    PubMed

    Pärkö, A

    1990-01-01

    This paper is a continuation of the author's study published in 1975. The teeth of the school children included in the study were first examined in 1952, re-examined in 1972 and subsequently at 5-year intervals. Children in the village of Salo had drinking water with a high fluride content and those in the village of Suontaka drank water with a low fluoride content. In the first examination, the Salo children showed a caries prevalence, measured with the DMF inxed, ca. 67% lower than the Suontaka children. With some exceptions, such as the first molars, the absolute differences in caries prevalence between subjects from the two villages had remained practically the same throughout the years. By the 1987 examination, the difference had been reduced, measured with the DMF index, to about 23% and with the DMFS index, to about 28%. In the last 5 years (1982-87), the DMFS index of the Suontaka pupils increased by 2.5 and that of the Salo pupils by 4.1. In the preceding two 5-year periods the increment in each group was ca. 7.0%. PMID:2287611

  3. Synemon ignita sp. nov., a new sun moth species from southern Australia (Lepidoptera, Castniidae).

    PubMed

    Kallies, Axel; Edwards, Ted; Young, Andy; Douglas, Fabian

    2016-01-01

    Sun moths (Castniidae) constitute a family of day-flying moths that due to their slim bodies, broad and often richly coloured wings and clubbed antennae closely resemble butterflies. However, despite this superficial similarity, sun moths are not related to butterflies but belong to the diverse cossoid assemblage of lepidopterous families (Edwards et al. 1998). Until recently, Castniidae were assigned to the superfamily Sesioidea (Minet 1991). A molecular study by Mutanen et al. (2010), however, failed to find support for a close relationship of Sesiidae and Castniidae, resulting in the inclusion of both families in a larger concept of Cossoidea (Nieukerken et al. 2011). In contrast, Heikkil et al. (2015) who added considerable morphological data to DNA, recovered Sesioidea as monophyletic, with Sesiidae, Castniidae and Brachodidae as constituent families, yet with low support values. Thus, although the monophyly of Castniidae is well supported, the systematic position of this family is unresolved. PMID:27394467

  4. Temperature fluctuations and their statistics in electron systems out of equilibrium

    NASA Astrophysics Data System (ADS)

    Heikkilä, Tero; Laakso, Matti; Nazarov, Yuli

    2010-03-01

    We study the fluctuations of the electron temperature in a metallic island coupled to reservoirs via resistive contacts and driven out of equilibrium by either a temperature or voltage difference between the reservoirs in the regime in which the electrons are completely decoupled from the lattice phonons. We quantify these fluctuations in the regime beyond the Gaussian approximation and elucidate their dependence on the nature of the electronic contacts.footnotetextTero T. Heikkil"a and Yuli V. Nazarov, Phys. Rev. Lett. 102, 130605 (2009). Besides normal noninteracting contacts, we also study the temperature fluctuations and their effects on other transport properties in single-electron transistors. We find three distinct regimes corresponding to cotunneling, sequential tunneling, and their coexistence. We find that the Fano factor of current fluctuations is enhanced around the crossover from coexistence to sequential tunneling by several orders of magnitude. This is because the SET is very sensitive to temperature fluctuations around this crossover. We also study the statistics of temperature fluctuations in these regimes and find the distribution to be strongly non-Gaussian.

  5. The Structure and Molecular Parameters of Camphene Determined by Fourier Transform Microwave Spectroscopy and Quantum Chemical Calculations

    NASA Astrophysics Data System (ADS)

    Neeman, Elias M.; Dréan, Pascal; Huet, T. R.

    2016-06-01

    The emission of volatile organic compounds, from plants has strong revelance for plant physiology, plant ecology and atmospheric chemistry. Camphene (C10H16) is a bicyclic monoterpene which is emitted in the atmosphere by biogenic sources. The structure of the unique stable conformer was optimized using density functional theory and ab initio calculations. The rotational spectrum of camphene was recorded in a supersonic jet expansion with a Fourier transform microwave spectrometer over the range 2-20 GHz. Signals from the parent species and from the ten 13C isotopomers were observed in natural abundance. The rotational and centrifugal distortion parameters were fitted to a Watson's Hamiltonian in the A-reduction. A magnetic hyperfine structure associated with the pairs of hydrogen nuclei in the methylene groups was observed and modeled.The rotational constants coupled to the equilibrium structure calculations were used to determine the r_0 and the r_m(1) gas-phase geometries of the carbon skeleton. The present work provides the first spectroscopic characterization of camphene in the gas phase and these results are also relevant for ozonolysis kinetics study through Criegee intermediates. R. Baraldi, F. Rapparini, O. Facini, D. Spano and P. Duce, Journal of Mediterranean Ecology, Vol.6, No.1, (2005). A. Bracho-Nunez, N. M. Knothe, S. Welter, M. Staudt, W. R. Costa, M. A. R. Liberato, M. T. F. Piedade, and J. Kesselmeier Biogeosciences, 10, 5855-5873, (2013). Minna Kivimäenpää, Narantsetseg Magsarjav, Rajendra Ghimire, Juha-Matti Markkanen, Juha Heijari, Martti Vuorinen and Jarmo K. Holopainen, Atmospheric Environment, 60, 477-485, (2012). R.C. de M. Oliveira and G. F. Bauerfeldt, J. Phys. Chem. A, 119 2802-2812 (2015)

  6. The orbitozygomatic stich: A technical modification of the lateral supraorbital approach

    PubMed Central

    Lazukova, Miroslava; Andrade-Barazarte, Hugo; Makhamov, Mahkham; Kivelev, Juri; Goehre, Felix; Jahromi, Behnam Rezai; Ibrahim, Tarik F.; Araujo, Ricardo; Lehto, Hanna; Hernesniemi, Juha A.

    2016-01-01

    Background: The lateral supraorbital approach (LSO) provides access to a variety of pathologies including anterior and some posterior circulation aneurysms, sellar and suprasellar lesions, and anterior fossa tumors. Technical modifications of LSO improve the surgical exposure of the skull base. Methods: We retrospectively analyzed 73 consecutive patients treated by the senior author (Juha A. Hernesniemi), at the Department of Neurosurgery, Helsinki University Hospital in Helsinki, Finland from May 2013 to October 2013. This study cohort underwent a modified LSO to access anterior circulation aneurysms, sellar and suprasellar tumors, and anterior fossa tumors. The studied population comprised 30 men and 43 women, with a mean age at treatment of 54 years (9–83 years). Results: LSO was successfully used to access anterior circulation aneurysms in 59 (81%) patients, 10 (14%) patients with anterior cranial fossa tumors, and 4 (5%) patients with suprasellar tumors. The skull base drilling provided a mean of 6.8 mm (1.7–22 mm) in increased exposure. Conclusion: LSO provides adequate access to vascular and neoplastic lesions of the anterior cranial fossa, by drilling approximately 6.8 mm (1.7–22 mm) of the lateral orbital wall and sphenoid wing. This enhances surgical exposure and trajectory. An additional trick while performing an LSO is to place a single or multiple stiches (orbitozygomatic stich) at the base of the dura once opened, eliminating the dead space between the dura and anterior skull base. PMID:27168949

  7. The influence of target irradiation conditions on the parameters of laser-produced plasma jets

    NASA Astrophysics Data System (ADS)

    Kasperczuk, A.; Pisarczyk, T.; Borodziuk, S.; Ullschmied, J.; Krousky, E.; Masek, K.; Pfeifer, M.; Rohlena, K.; Skala, J.; Pisarczyk, P.

    2007-03-01

    Recent experimental results demonstrate that the forming of plasma jets is a fundamental process accompanying the laser-produced plasma expansion, if a massive planar target with relatively high atomic number is irradiated by a defocused laser beam. In this paper some new results on the influence of target irradiation conditions on plasma jet parameters are presented. The experiment was carried out at the Prague Asterix Laser System (PALS) iodine laser [K. Jungwirth, A. Cejnarova, L. Juha, B. Kralikova, J. Krasa, E. Krousky, P. Krupickova, L. Laska, K. Masek, A. Prag, O. Renner, K. Rohlena, B. Rus, J. Skala, P. Straka, and J. Ullschmied, Phys. Plasmas 8, 2495 (2001)]. with the third harmonic beam of the pulse duration of 250ps. The beam energies varied in the range of 13-160J. The planar massive targets used in the experiment were made of copper. For measurements of the electron density evolution a three frame interferometric system was employed. The jets were produced in the whole range of the laser energy used. Calculations of the efficiency of the plasma jet production show that it decreases with increasing the laser energy.

  8. Influence of the focal point position on the properties of a laser-produced plasma

    SciTech Connect

    Kasperczuk, A.; Pisarczyk, T.; Badziak, J.; Miklaszewski, R.; Parys, P.; Rosinski, M.; Wolowski, J.; Stenz, CH.; Ullschmied, J.; Krousky, E.; Masek, K.; Pfeifer, M.; Rohlena, K.; Skala, J.; Pisarczyk, P.

    2007-10-15

    This paper deals with investigations of the influence of the focusing lens focal point position on the properties of a plasma produced by a defocused laser beam. The experiment was carried out at the Prague Asterix Laser System iodine laser [K. Jungwirth, A. Cejnarova, L. Juha, B. Kralikova, J. Krasa, E. Krousky, P. Krupickova, L. Laska, K. Masek, T. Mocek, M. Pfeifer, A. Prag, O. Renner, K. Rohlena, B. Rus, J. Skala, P. Straka, and J. Ullschmied, Phys. Plasmas 8, 2495 (2001)] by using the third harmonic of laser radiation ({lambda}=0.438 {mu}m), laser energy of 70 J, pulse duration of 250 ps (full width at half-maximum), and beam spot radii of 250 and 400 {mu}m. Cu and Ta were chosen as target materials. The experimental data were obtained by means of a three-frame interferometric system, ion collectors, and crater replica techniques. The reported results allow formulating an important hypothesis that the laser-produced plasma modifies strongly the laser intensity distribution. It is shown how such a modification depends on the relative position and distance of the focal point to the target surface. Of particular importance is whether the focal point is located inside or in front of the target. The irradiation geometry is crucial for the possibility of generating plasma jets by laser radiation. Well-formed jet-like plasma structures can be created if an initially homogeneous laser intensity distribution is transformed in the plasma to an annular one.

  9. Influence of the focal point position on the properties of a laser-produced plasma

    NASA Astrophysics Data System (ADS)

    Kasperczuk, A.; Pisarczyk, T.; Badziak, J.; Miklaszewski, R.; Parys, P.; Rosinski, M.; Wolowski, J.; Stenz, CH.; Ullschmied, J.; Krousky, E.; Masek, K.; Pfeifer, M.; Rohlena, K.; Skala, J.; Pisarczyk, P.

    2007-10-01

    This paper deals with investigations of the influence of the focusing lens focal point position on the properties of a plasma produced by a defocused laser beam. The experiment was carried out at the Prague Asterix Laser System iodine laser [K. Jungwirth, A. Cejnarova, L. Juha, B. Kralikova, J. Krasa, E. Krousky, P. Krupickova, L. Laska, K. Masek, T. Mocek, M. Pfeifer, A. Prag, O. Renner, K. Rohlena, B. Rus, J. Skala, P. Straka, and J. Ullschmied, Phys. Plasmas 8, 2495 (2001)] by using the third harmonic of laser radiation (λ=0.438μm), laser energy of 70J, pulse duration of 250ps (full width at half-maximum), and beam spot radii of 250 and 400μm. Cu and Ta were chosen as target materials. The experimental data were obtained by means of a three-frame interferometric system, ion collectors, and crater replica techniques. The reported results allow formulating an important hypothesis that the laser-produced plasma modifies strongly the laser intensity distribution. It is shown how such a modification depends on the relative position and distance of the focal point to the target surface. Of particular importance is whether the focal point is located inside or in front of the target. The irradiation geometry is crucial for the possibility of generating plasma jets by laser radiation. Well-formed jet-like plasma structures can be created if an initially homogeneous laser intensity distribution is transformed in the plasma to an annular one.

  10. The influence of target irradiation conditions on the parameters of laser-produced plasma jets

    SciTech Connect

    Kasperczuk, A.; Pisarczyk, T.; Borodziuk, S.; Ullschmied, J.; Krousky, E.; Masek, K.; Pfeifer, M.; Rohlena, K.; Skala, J.; Pisarczyk, P.

    2007-03-15

    Recent experimental results demonstrate that the forming of plasma jets is a fundamental process accompanying the laser-produced plasma expansion, if a massive planar target with relatively high atomic number is irradiated by a defocused laser beam. In this paper some new results on the influence of target irradiation conditions on plasma jet parameters are presented. The experiment was carried out at the Prague Asterix Laser System (PALS) iodine laser [K. Jungwirth, A. Cejnarova, L. Juha, B. Kralikova, J. Krasa, E. Krousky, P. Krupickova, L. Laska, K. Masek, A. Prag, O. Renner, K. Rohlena, B. Rus, J. Skala, P. Straka, and J. Ullschmied, Phys. Plasmas 8, 2495 (2001)]. with the third harmonic beam of the pulse duration of 250 ps. The beam energies varied in the range of 13-160 J. The planar massive targets used in the experiment were made of copper. For measurements of the electron density evolution a three frame interferometric system was employed. The jets were produced in the whole range of the laser energy used. Calculations of the efficiency of the plasma jet production show that it decreases with increasing the laser energy.

  11. Stable dense plasma jets produced at laser power densities around 1014 W/cm2

    NASA Astrophysics Data System (ADS)

    Kasperczuk, A.; Pisarczyk, T.; Borodziuk, S.; Ullschmied, J.; Krousky, E.; Masek, K.; Rohlena, K.; Skala, J.; Hora, H.

    2006-06-01

    The results of investigations are presented that are connected with defocused laser beam-planar target interaction. Following the very large focus laser-plasma interaction experiments on the Nova [H. T. Powell, J. A. Caird, J. E. Murray, and C. E. Thompson, 1991 ICF Annual Report UCRL-LR-105820-91, p. 163 (1991)] and GEKKO-XII [C. Yamanaka, Y. Kato, Y. Izawa, K. Yoshida, T. Yamanaka, T. Sasaki, T. Nakatsuka, J. Kuroda, and S. Nakai, IEEE J. Quantum Electron. QE-17, 1639 (1981)] lasers, as well as on the National Ignition Facility (NIF) laser [W. J. Hogan, E. I. Moses, B. E. Warner, M. S. Sorem, and J. M. Soures, Nucl. Fusion 41, 567 (2001)] with generation of high Mach number jets, this paper is devoted to similar jet generation with very detailed measurements of density profiles by using high-power lasers at large focus conditions. The experiment was carried out with target materials of different mass densities (Al, Cu, Ag, Ta, and Pb) using the Prague Asterix Laser System (PALS) iodine laser [K. Jungwirth, A. Cejnarova, L. Juha, B. Kralikowa, J. Krasa, E. Krousky, P. Krupickova, L. Laska, K. Masek, A. Prag, O. Renner, K. Rohlena, B. Rus, J. Skala, P. Straka, and J. Ullschmied, Phys. Plasmas 8, 2495 (2001)]. The investigations were conducted for the laser radiation energy of 100J at two wavelengths of 1.315 and 0.438μm (the first and third harmonics of laser radiation), pulse duration of 0.4ns, and a focal spot radius of 300μm. Most of the experimental data were obtained by means of a three-frame laser interferometer and an x-ray streak camera; the crater parameters were obtained by using the crater replica technique. These investigations have shown that stable dense plasma jets can be produced in a simple configuration of laser beam-planar target interaction, provided that a proper target material is used.

  12. Stable dense plasma jets produced at laser power densities around 10{sup 14} W/cm{sup 2}

    SciTech Connect

    Kasperczuk, A.; Pisarczyk, T.; Borodziuk, S.; Ullschmied, J.; Krousky, E.; Masek, K.; Rohlena, K.; Skala, J.; Hora, H.

    2006-06-15

    The results of investigations are presented that are connected with defocused laser beam-planar target interaction. Following the very large focus laser-plasma interaction experiments on the Nova [H. T. Powell, J. A. Caird, J. E. Murray, and C. E. Thompson, 1991 ICF Annual Report UCRL-LR-105820-91, p. 163 (1991)] and GEKKO-XII [C. Yamanaka, Y. Kato, Y. Izawa, K. Yoshida, T. Yamanaka, T. Sasaki, T. Nakatsuka, J. Kuroda, and S. Nakai, IEEE J. Quantum Electron. QE-17, 1639 (1981)] lasers, as well as on the National Ignition Facility (NIF) laser [W. J. Hogan, E. I. Moses, B. E. Warner, M. S. Sorem, and J. M. Soures, Nucl. Fusion 41, 567 (2001)] with generation of high Mach number jets, this paper is devoted to similar jet generation with very detailed measurements of density profiles by using high-power lasers at large focus conditions. The experiment was carried out with target materials of different mass densities (Al, Cu, Ag, Ta, and Pb) using the Prague Asterix Laser System (PALS) iodine laser [K. Jungwirth, A. Cejnarova, L. Juha, B. Kralikowa, J. Krasa, E. Krousky, P. Krupickova, L. Laska, K. Masek, A. Prag, O. Renner, K. Rohlena, B. Rus, J. Skala, P. Straka, and J. Ullschmied, Phys. Plasmas 8, 2495 (2001)]. The investigations were conducted for the laser radiation energy of 100 J at two wavelengths of 1.315 and 0.438 {mu}m (the first and third harmonics of laser radiation), pulse duration of 0.4 ns, and a focal spot radius of 300 {mu}m. Most of the experimental data were obtained by means of a three-frame laser interferometer and an x-ray streak camera; the crater parameters were obtained by using the crater replica technique. These investigations have shown that stable dense plasma jets can be produced in a simple configuration of laser beam-planar target interaction, provided that a proper target material is used.

  13. Integration of atomic layer deposited nanolaminates on silicon waveguides (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Autere, Anton; Karvonen, Lasse; Säynätjoki, Antti; Roussey, Matthieu; Roenn, John; Färm, Elina; Kemell, Marianna; Tu, Xiaoguang; Liow, Tsung-Yang; Lo, Patrick; Ritala, Mikko; Leskelä, Markku; Lipsanen, Harri; Honkanen, Seppo; Sun, Zhipei

    2016-05-01

    waveguides and show signal enhancement. Our results show that atomic layer deposited nanolaminates can potentially open new possibilities for various photonic applications, such as silicon photonic devices for light emission and amplification, optical sensing and all-optical signal processing. References [1] A. Autere, L. Karvonen, A. Säynätjoki, M. Roussey, E. Färm, M. Kemell, X. Tu, T.Y. Liow, G.Q. Lo, M. Ritala, M. Leskelä, S. Honkanen, H. Lipsanen, and Z. Sun, "Slot waveguide ring resonators coated by an atomic layer deposited organic/inorganic nanolaminate," Opt. Express 23, 26940-26951 (2015) [2] L. D. Salmi, E. Puukilainen, M. Vehkamäki, M. Heikkilä, and M. Ritala, "Atomic layer deposition of Ta2O5/polyimide nanolaminates," Chem. Vap. Deposition 15, 221-226 (2009). [3] S. Morino, T. Yamashita, K. Horie, T. Wada, and H. Sasabe, "Third-order nonlinear optical properties of aromatic polyisoimides," React. Funct. Polym. 44, 183-188 (2000). [4] C.-Y. Tai, J. Wilkinson, N. Perney, M. Netti, F. Cattaneo, C. Finlayson, and J. Baumberg, "Determination of nonlinear refractive index in a Ta2O5 rib waveguide using self-phase modulation," Opt. Express 12, 5110-5116 (2004).

  14. Snow Water Equivalent Retrieval By Markov Chain Monte Carlo Based on Memls and Hut Snow Emission Model

    NASA Astrophysics Data System (ADS)

    Pan, J.; Durand, M. T.; Vanderjagt, B. J.

    2014-12-01

    The Markov chain Monte Carlo (MCMC) method had been proved to be successful in snow water equivalent retrieval based on synthetic point-scale passive microwave brightness temperature (TB) observations. This method needs only general prior information about distribution of snow parameters, and could estimate layered snow properties, including the thickness, temperature, density and snow grain size (or exponential correlation length) of each layer. In this study, the multi-layer HUT (Helsinki University of Technology) model and the MEMLS (Microwave Emission Model of Layered Snowpacks) will be used as observation models to assimilate the observed TB into snow parameter prediction. Previous studies had shown that the multi-layer HUT model tends to underestimate TB at 37 GHz for deep snow, while the MEMLS does not show sensitivity of model bias to snow depth. Therefore, results using HUT model and MEMLS will be compared to see how the observation model will influence the retrieval of snow parameters. The radiometric measurements at 10.65, 18.7, 36.5 and 90 GHz at Sodankyla, Finland will be used as MCMC input, and the statistics of all snow property measurement will be used to calculate the prior information. 43 dry snowpits with complete measurements of all snow parameters will be used for validation. The entire dataset are from NorSREx (Nordic Snow Radar Experiment) experiments carried out by Juha Lemmetyinen, Anna Kontu and Jouni Pulliainen in FMI in 2009-2011 winters, and continued two more winters from 2011 to Spring of 2013. Besides the snow thickness and snow density that are directly related to snow water equivalent, other parameters will be compared with observations, too. For thin snow, the previous studies showed that influence of underlying soil is considerable, especially when the soil is half frozen with part of unfrozen liquid water and part of ice. Therefore, this study will also try to employ a simple frozen soil permittivity model to improve the

  15. FOREWORD: The 70th birthday of Professor Stig Stenholm The 70th birthday of Professor Stig Stenholm

    NASA Astrophysics Data System (ADS)

    Suominen, Kalle-Antti

    2010-09-01

    It is not easy to assess, or even to describe correctly a long and distinguished career that started about the time when I was born. In 1964 Stig Stenholm got both an engineering degree at the Helsinki University of Technology (HUT), and an MSc degree (in Mathematics) at the University of Helsinki. The two degrees demonstrate Stig's ability to understand both complex mathematics and experimental physics. Statistical physics or rather, quantum liquids, was the field in which Stig got his DPhil at Oxford in 1967, under the guidance of Dirk ter Haar. It is interesting that together they worked on studying fermions in a bosonic background [1]; at the time this meant, of course, 3He atoms as impurities in 4He liquid, but nowadays one would immediately connect such systems to the physics of cold atomic gases. The postdoctoral period in 1967-1968 at Yale University brought Stig in contact with Willis Lamb and laser physics [2]. Back in Finland, Stig's career in the 1970s was dominated by theoretical studies of gas lasers, especially pressure and collision effects on spectral lines and saturation spectroscopy, together with his first PhD student, Rainer Salomaa. A professorship at the University of Helsinki came in 1974, and in 1980 an important era started as Stig became the scientific director of the Research Institute for Theoretical Physics (TFT). At that time he also developed the semiclassical theory of laser cooling especially with Juha Javanainen. The laser spectroscopy work led to a textbook in 1984 [3], and the semiclassical laser cooling theory was summarized in a review article in 1986 [4]. These were not, of course, his only interests, as he also worked on free-electron lasers, ring-laser gyroscopes, multiphoton processes and quantum amplifiers. In an article written in 1990 in honour of Olli Lounasmaa [5], the founder of the famous Low Temperature Laboratory at HUT, Stig mentions that one of his most memorable achievements was acting as a bridge between the

  16. Extreme weather impacts on European networks of transport

    NASA Astrophysics Data System (ADS)

    Leviakangas, P.

    2012-04-01

    : Pekka Leviäkangas, Anu Tuominen, Riitta Molarius, Heta Kojo, Jari Schabel, Sirra Toivonen, Jaana Keränen, Johanna Ludvigsen, Andrea Vajda, Heikki Tuomenvirta, Ilkka Juga, Pertti Nurmi, Jenni Rauhala, Frank Rehm, Thomas Gerz, Thorsten Muehlhausen, Juha Schweighofer, Silas Michaelides, Matheos Papadakis, Nikolai Dotzek (†), Pieter Groenemeijer.

  17. FOREWORD: The 70th birthday of Professor Stig Stenholm The 70th birthday of Professor Stig Stenholm

    NASA Astrophysics Data System (ADS)

    Suominen, Kalle-Antti

    2010-09-01

    It is not easy to assess, or even to describe correctly a long and distinguished career that started about the time when I was born. In 1964 Stig Stenholm got both an engineering degree at the Helsinki University of Technology (HUT), and an MSc degree (in Mathematics) at the University of Helsinki. The two degrees demonstrate Stig's ability to understand both complex mathematics and experimental physics. Statistical physics or rather, quantum liquids, was the field in which Stig got his DPhil at Oxford in 1967, under the guidance of Dirk ter Haar. It is interesting that together they worked on studying fermions in a bosonic background [1]; at the time this meant, of course, 3He atoms as impurities in 4He liquid, but nowadays one would immediately connect such systems to the physics of cold atomic gases. The postdoctoral period in 1967-1968 at Yale University brought Stig in contact with Willis Lamb and laser physics [2]. Back in Finland, Stig's career in the 1970s was dominated by theoretical studies of gas lasers, especially pressure and collision effects on spectral lines and saturation spectroscopy, together with his first PhD student, Rainer Salomaa. A professorship at the University of Helsinki came in 1974, and in 1980 an important era started as Stig became the scientific director of the Research Institute for Theoretical Physics (TFT). At that time he also developed the semiclassical theory of laser cooling especially with Juha Javanainen. The laser spectroscopy work led to a textbook in 1984 [3], and the semiclassical laser cooling theory was summarized in a review article in 1986 [4]. These were not, of course, his only interests, as he also worked on free-electron lasers, ring-laser gyroscopes, multiphoton processes and quantum amplifiers. In an article written in 1990 in honour of Olli Lounasmaa [5], the founder of the famous Low Temperature Laboratory at HUT, Stig mentions that one of his most memorable achievements was acting as a bridge between the

  18. Feeding the Monster

    NASA Astrophysics Data System (ADS)

    2005-10-01

    central network of filamentary structures spiralling down to the centre. "Our analysis of the VLT/NACO images of NGC 1097 shows that these filaments end up at the very centre of the galaxy", says co-author Juha Reunanen from ESO. "This network closely resembles those seen in computer models", adds co-worker Witold Maciejewski from the University of Oxford, UK. "The nuclear filaments revealed in the NACO images are the tracers of cold dust and gas being channelled towards the centre to eventually ignite the AGN." The astronomers also note that the curling of the spiral pattern in the innermost 300 light-years seem indeed to confirm the presence of a super-massive black hole in the centre of NGC 1097. Such a black hole in the centre of a galaxy causes the nuclear spiral to wind up as it approaches the centre, while in its absence the spiral would be unwinding as it moves closer to the centre. An image of NGC 1097 and its small companion, NGC 1097A, was taken in December 2004, in the presence of Chilean President Lagos with the VIMOS instrument on ESO's Very Large Telescope (VLT). It is available as ESO PR Photo 35d/04. More information This ESO Press Photo is based on research published in the October issue of Astronomical Journal, vol. 130, p. 1472 ("Feeding the Monster: The Nucleus of NGC 1097 at Subarcsecond Scales in the Infrared with the Very Large Telescope", by M. Almudena Prieto, Witold Maciejewski, and Juha Reunanen).

  19. The Effect of Pollution on Newly-Formed Particle Composition in Boreal Forest

    NASA Astrophysics Data System (ADS)

    Vaattovaara, Petri

    2010-05-01

    Petri Vaattovaara (1), Tuukka Petäjä (2), Jorma Joutsensaari (1), Pasi Miettinen (1), Boris Zaprudin (1,6), Aki Kortelainen (1), Juha Heijari (3,7), Pasi Yli-Pirilä (3), Pasi Aalto (2), Doug R. Worsnop (4), and Ari Laaksonen(1,5) (1) University of Eastern Finland, Finland (2) University of Helsinki, Finland (3) University of Eastern Finland, Finland (4) Aerodyne Research Inc., USA (5) Finnish Meteorological Institute, Finland (6) Currently at University of Turku, Finland (7) Currently at Maritime Research Centre, Finland Email address of the Corresponding author: Petri.Vaattovaara@uef.fi The geographical extent of the tropical, temperate and boreal forests is about 30% of the Earth's land surface. Those forests are located around the world in different climate zones effecting widely on atmospheric composition via new particle formation. The Boreal forests solely cover one third of the forests extent and are one of the largest vegetation environments, forming a circumpolar band throughout the northern hemisphere continents, with a high potential to affect climate processes [1]. In order to more fully understand the possible climatic effects of the forests, the properties of secondary organic aerosols (SOA) in varying conditions (e.g. a change in meteorological parameters or in the concentrations of biogenic and antropogenic trace gases) need to be better known. In this study, we applied the UFO-TDMA (ultrafine organic tandem differential mobility analyzer [2]) and the UFH-TDMA (ultrafine hygroscopicity tandem differential mobility analyzer [3]) methods parallel to shed light on the evolution of the nucleation and Aitken mode particle compositions (via physic-chemical properties) at a virgin boreal forest site in varying conditions. The measurements were carried out at Hyytiälä forest station in Northern Europe (Finland) during 15 spring nucleation events. We also carried out a statistical analysis using linear correlations in order to explain the variability in

  20. MIRAS characterization and monitoring during the SMOS In-Orbit Commissioning Phase

    NASA Astrophysics Data System (ADS)

    Corbella, I.; Torres, F.; Martin-Neira, M.; Duffo, N.; González-Gambau, V.; Camps, A.; Vall-Llossera, M.

    2009-04-01

    for the in-orbit commissioning phase. The tool can ingest raw data from the electronic ground support equipment (EGSE) developed by the instrument manufacturer and also from the nominal level 0 data provided by the SMOS ground segment data acquisition system. The software classifies the input data and applies the calibration procedures to produce calibrated visibility and brightness temperature. Most of the intermediate results, including raw data and calibration parameters, are saved in files for further analysis and processing. The processing has been optimized for speed so that the results are produced in near real time and it is designed to process large amount of data in a continuous way. Finally, the tool includes a user-friendly graphics interface that allows selecting specific data according to different parameters (baselines or receivers, modes of operation or others). 4 Conclusions During the SMOS In-Orbit Commissioning Phase, a number of tests will be carried out in order to check the payload MIRAS operation and fully characterize it in terms of data consistency and calibration parameters. The UPC team is in charge of analyzing the data and develop the procedures to verify that the final data meets the required specifications. The procedures for this have been summarized and will be presented at the conference in more detail. References [1] Michael Brown, "SMOS in-orbit commissioning phase plan," Tech. Rep. SO-PL-ESA-SYS-5505, issue 1.1, ESA-ESTEC, The Netherlands, 8 August 2008. [2] Ignasi Corbella, Francesc Torres, Nuria Duffo, Manuel Martín-Neira, Verónica González, Adriano Camps, and Mercè Vall-llossera, "MIRAS ground characterization," in 10th Specialist Meeting on Microwave Radiometry and Remote Sensing of the Environment - Rad 2008, Florence, Italy, 11-14 March 2008, Istituto di Fisica Applicata "N.Carrara" (IFAC-CNR), pp. 1-4. [3] Manuel Martín-Neira, Martin Suess, and Juha Kainulainen, "The flat target transformation," IEEE Transactions on

  1. SINFONI Opens with Upbeat Chords

    NASA Astrophysics Data System (ADS)

    2004-08-01

    the development of SINFONI for nearly 7 years. Some of the members of the Commissioning Teams are depicted in PR Photos 24g/04 and 24h/04; in addition to the SPIFFI team members present on the second photo, Walter Bornemann, Reinhard Genzel, Hans Gemperlein, Stefan Huber have also been working on the reintegration/commissioning in Paranal. Notes [1] This press release is issued in coordination between ESO, the Max-Planck-Institute for Extraterrestrial Physics (MPE) in Garching, Germany, and the Nederlandse Onderzoekschool Voor Astronomie in Leiden, The Netherlands. A German version is available at http://www.mpg.de/bilderBerichteDokumente/dokumentation/pressemitteilungen/2004/pressemitteilung20040824/index.html and a Dutch version at http://www.astronomy.nl/inhoud/pers/persberichten/30_08_04.html. [2] The SINFONI team consists of Roberto Abuter, Andrew Baker, Walter Bornemann, Ric Davies, Frank Eisenhauer (SPIFFI Principal Investigator), Hans Gemperlein, Reinhard Genzel (MPE Director), Andrea Gilbert, Armin Goldbrunner, Matthew Horrobin, Stefan Huber, Christof Iserlohe, Matthew Lehnert, Werner Lieb, Dieter Lutz, Nicole Nesvadba, Claudia Röhrle, Jürgen Schreiber, Linda Tacconi, Matthias Tecza, Niranjan Thatte, Harald Weisz (Max-Planck-Institut für Extraterrestrische Physik, Garching, Germany), Anthony Brown, Paul van der Werf (NOVA, Leiden, The Netherlands), Eddy Elswijk, Johan Pragt, Jan Kragt, Gabby Kroes, Ton Schoenmaker, Rik ter Horst (ASTRON, Dwingeloo, The Netherlands), Henri Bonnet (SINFONI Project Manager), Roberto Castillo, Ralf Conzelmann, Romuald Damster, Bernard Delabre, Christophe Dupuy, Robert Donaldson, Christophe Dumas, Enrico Fedrigo, Gert Finger, Gordon Gillet, Norbert Hubin (Head of Adaptive Optics Dept.), Andreas Kaufer, Franz Koch, Johann Kolb, Andrea Modigliani, Guy Monnet (Head of Telescope Systems Division), Chris Lidman, Jochen Liske, Jean Louis Lizon, Markus Kissler-Patig (SINFONI Instrument Scientist), Jerome Paufique, Juha Reunanen