1,342 research outputs found
No Effect of Steady Rotation on Solid He in a Torsional Oscillator
We have measured the response of a torsional oscillator containing
polycrystalline hcp solid He to applied steady rotation in an attempt to
verify the observations of several other groups that were initially interpreted
as evidence for macroscopic quantum effects. The geometry of the cell was that
of a simple annulus, with a fill line of relatively narrow diameter in the
centre of the torsion rod. Varying the angular velocity of rotation up to
2\,rad\,s showed that there were no step-like features in the resonant
frequency or dissipation of the oscillator and no history dependence, even
though we achieved the sensitivity required to detect the various effects seen
in earlier experiments on other rotating cryostats. All small changes during
rotation were consistent with those occurring with an empty cell. We thus
observed no effects on the samples of solid He attributable to steady
rotation.Comment: 8 pages, 3 figures, accepted in J. Low Temp. Phy
Massa- ja paperiteollisuuden supistumisen ja tulevaisuuden kuvien aluetaloudelliset vaikutukset
Tutkimus on jatkoa Ruralia-instituutin syksyllä 2008 julkaisemalle metsäteollisuuden mahdollisen supistumisen aluetaloudellisia vaikutuksia selvittäneelle työlle. Päivitetty tutkimus on edellistä kattavampi, sillä selvitys ulottuu nyt kaikkiin Suomen massa- ja paperiteollisuuden yrityksiin. Massa- ja paperiteollisuuden vuoden 2007 alusta syksyyn 2009 ilmoittamat pysyvät kapasiteetin leikkaukset ovat yhteensä lähes 19,0 % vuoden 2007 tasoon verrattuna. Massan valmistuksessa menetykset ovat yli 20 % ja paperin/kartongin valmistuksessa noin 17 %. Supistamispäätökset merkitsevät kerroinvaikutuksineen yhteensä 1,4 miljardin euron ja 8 800 henkilötyövuoden menetystä. Kun vähennykset suhteutetaan menetyksiä kärsineiden maakuntien yhteenlaskettuun BKT:n ja työllisten määrään, toimenpiteet vastaavat 2,0 % laskua taloudellisessa kasvussa ja 0,8 % menetystä työllisyydessä. Vuoden 2008 lopulla vastaavat menetykset olivat 0,9 miljardia euroa ja 6 000 henkilötyövuotta.
Vaikeudet keskittyvät itäiseen Suomeen. Kymenlaakso on kärsinyt suurimmat menetykset rahallisesti ja työllisten määrässä. Suhteellisesti eniten on menettänyt Kainuu. Pohjois-Savo nousee menettäjänä kolmen kärkeen, jos Stora Enson Varkauden tehtaiden sulkeminen toteutuu vuoden 2010 lopussa. Myös Keski-Suomessa, Lapissa ja Pohjanmaalla on suljettu kokonaisia tehtaita ja tästä on tullut selviä vaurioita. Pienemmillä tappioilla ovat selvinneet Etelä-Karjala, Pohjois-Karjala, Pohjois-Pohjanmaa ja Satakunta, joissa on ollut vain tuotannon seisokkeja ja/tai yksittäisiä tuotantolinjojen sulkemisia. Alueet, joiden elinkeinorakenne on monipuolinen, sopeutuvat nopeammin metsäteollisuuden supistumiseen. Tämä näkyy muun muassa pienempinä työllisyysmenetyksinä. Lisäksi aluetalouden koolla on merkitystä. Pienille aluetalouksille vaikutukset ovat voimakkaammat.
Tutkimuksessa tarkasteltiin myös metsäteollisuuden rakennemuutoksen etenemisen vaikutuksia. Jos kehitys jatkuu negatiivisena, kuten Metla esitti keväällä 2009 tai pelätty kauhuskenaario alan tuotannon puoliintumisesta toteutuisi, kansantalouden menetykset olisivat merkittävät. Metlan skenaariossa BKT:n vähentyminen olisi kumulatiivisesti laskettuna suurimmillaan vuosien 2009 ja 2013 aikana, noin 450 miljoonaa euroa. Vastaavasti kauhuskenaariossa summa olisi lähes 700 miljoonaa euroa. Menetystä korostaa talouslama, minkä vuoksi muut alat eivät pysty täysin kompensoimaan massa- ja paperiteollisuuden vaikeuksia. Kokonaistuotanto näyttäisi kuitenkin toipuvan, mikäli nykyinen lama jäisi lyhyeksi. Työllisyys kärsisi huomattavasti kummassakin negatiivisessa skenaariossa.
Vastapainoksi tutkittiin myös ns. sisäisen devalvaation sekä paperimarkkinoiden elpymisen vaikutusta. Sisäinen devalvaatio toteutuisi massa- ja paperiteollisuuden maltillisen palkkaratkaisun ja Ruotsin kruunun devalvoitumista vastaavan kustannusedun kautta. Kansainvälisten paperimarkkinoiden elpymisen vaikutusta tutkittiin vientihintoja ja -määriä nostamalla. Näistä tehokkaimmaksi osoittautui vientihintojen nousu. Myönteisten skenaarioiden vaikutusten ja nykyisten päätösten aiheuttamien aluetaloudellisten menetysten vertaaminen kuitenkin paljastaa, että vieläkin parempaa kehitystä vaaditaan. Kymenlaakso ja Pohjois-Savo jäisivät edelleen miinukselle
The benzoylarginine peptidase from Treponema denticola (strain ASLM), a human oral spirochaete: evidence for active-site carboxyl groups
The benzoylarginine peptidase of Treponema denticola (strain ASLM; a human oral spirochaete) was progressively and irreversibly inactivated by 1-(ethoxycarbonyl)-2-ethoxy-1, 2-dihydroquinoline, a carboxyl-group reagent. At acidic pH values, reaction of one mole of the modifier per active site of the enzyme resulted in total inactivation of the enzyme. Assuming that this modifier is a specific carboxyl reagent, the data suggest that the inactivation of the T. denticola benzoylarginine peptidase was caused by the modification of one carboxyl group located close to the active site of the enzyme. Results obtained with Woodward's reagent K ( N -ethyl-5-phenylisoxazolium 3’-sulphonate) supported these findings. Carbethoxylation with diethylpyrocarbonate effectively inactivated the enzyme, and addition of hydroxylamine at pH 7.0 restored the activity almost totally, suggesting that the pyrocarbonate had reacted with tyrosyl or histidyl residues.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73886/1/j.1365-2958.1990.tb00721.x.pd
Composite repetition-aware data structures
In highly repetitive strings, like collections of genomes from the same
species, distinct measures of repetition all grow sublinearly in the length of
the text, and indexes targeted to such strings typically depend only on one of
these measures. We describe two data structures whose size depends on multiple
measures of repetition at once, and that provide competitive tradeoffs between
the time for counting and reporting all the exact occurrences of a pattern, and
the space taken by the structure. The key component of our constructions is the
run-length encoded BWT (RLBWT), which takes space proportional to the number of
BWT runs: rather than augmenting RLBWT with suffix array samples, we combine it
with data structures from LZ77 indexes, which take space proportional to the
number of LZ77 factors, and with the compact directed acyclic word graph
(CDAWG), which takes space proportional to the number of extensions of maximal
repeats. The combination of CDAWG and RLBWT enables also a new representation
of the suffix tree, whose size depends again on the number of extensions of
maximal repeats, and that is powerful enough to support matching statistics and
constant-space traversal.Comment: (the name of the third co-author was inadvertently omitted from
previous version
The peptidolytic capacity of the spirochete system
Relatively scant chemical information has been available on the proteinases and peptidases of spirochetes in spite of the association of spirochetes with several serious infections known to plague humans and other animal species. This situation has partly resulted from difficulties in growing some spirochetes under laboratory conditions. The cells of Treponema denticola , a spirochete suggested to be associated with periodontal infections, have turned out to be a good source of new chemical information on those enzymes. Latest studies suggest that the outer cell en-velope or the periplasmic space of T. denticola contains several novel proteinases and peptidases (hence called ``ectoenzymes'') which may contribute to the chronicity of periodontal infections. Some of the oligopeptidases discovered are specific for proline-containing host tissue peptides such as substance P, bradykinin, neurotensin, etc., and possibly small collagen fragments. The only spirochetal peptidases purified to give a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis have been obtained from T. denticola . One particular peptidase, suggested to be similar to the oligopeptidase B (EC 3.4.21.83) of Escherichia coli seems to be present in the cell envelope or in the periplasmic space at quite large concentrations. The presence of this and several other peptidases in the outer cell structures of the treponemes suggests that such enzymes are important for the nutrition of these highly motile and invasive organisms. The biological role of these enzymes can thus be envisaged in the peptidolytic processing of host tissue proteins and peptides to gradually smaller molecules to fulfill the nutritional requirements of these organisms. Although the genetic similarity between T. denticola and some other treponemes and spirochetes can be hotly debated, it is nevertheless now possible to use T. denticula enzymes as suitable objects for comparison when the chemistry of other spirochetes is studied.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42252/1/430-185-1-1_61850001.pd
Kuusen ja männyn paksuuskasvu on sopeutunut paikalliseen ilmastoon
Artikkeli julkaistu alunperin metla.fi sivustoll
Developing LCA-based benchmarks for sustainable consumption - for and with users
This article presents the development process of a consumer-oriented, illustrative benchmarking tool enabling consumers to use the results of environmental life cycle assessment (LCA) to make informed decisions. Active and environmentally conscious consumers and environmental communicators were identified as key target groups for this type of information. A brochure presenting the benchmarking tool was developed as an participatory, iterative process involving consumer focus groups, stakeholder workshops and questionnaire-based feedback. In addition to learning what works and what does not, detailed suggestions on improved wording and figures were obtained, as well as a wealth of ideas for future applications
Suffix Tree of Alignment: An Efficient Index for Similar Data
We consider an index data structure for similar strings. The generalized
suffix tree can be a solution for this. The generalized suffix tree of two
strings and is a compacted trie representing all suffixes in and
. It has leaves and can be constructed in time.
However, if the two strings are similar, the generalized suffix tree is not
efficient because it does not exploit the similarity which is usually
represented as an alignment of and .
In this paper we propose a space/time-efficient suffix tree of alignment
which wisely exploits the similarity in an alignment. Our suffix tree for an
alignment of and has leaves where is the sum of
the lengths of all parts of different from and is the sum of the
lengths of some common parts of and . We did not compromise the pattern
search to reduce the space. Our suffix tree can be searched for a pattern
in time where is the number of occurrences of in and
. We also present an efficient algorithm to construct the suffix tree of
alignment. When the suffix tree is constructed from scratch, the algorithm
requires time where is the sum of the lengths
of other common substrings of and . When the suffix tree of is
already given, it requires time.Comment: 12 page
Elasticity of Poissonian fiber networks
An effective-medium model is introduced for the elasticity of two-dimensional random fiber networks. These networks are commonly used as basic models of heterogeneous fibrous structures such as paper. Using the exact Poissonian statistics to describe the microscopic geometry of the network, the tensile modulus can be expressed by a single-parameter function. This parameter depends on the network density and fiber dimensions, which relate the macroscopic modulus to the relative importance of axial and bending deformations of the fibers. The model agrees well with simulation results and experimental findings. We also discuss the possible generalizations of the model.Peer reviewe
Polyol-combinant saliva stimulants and oral health in Veterans Affairs patients—An exploratory study
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72530/1/j.1754-4505.1996.tb00843.x.pd
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