1,196 research outputs found
Energy landscapes, lowest gaps, and susceptibility of elastic manifolds at zero temperature
We study the effect of an external field on (1+1) and (2+1) dimensional
elastic manifolds, at zero temperature and with random bond disorder. Due to
the glassy energy landscape the configuration of a manifold changes often in
abrupt, ``first order'' -type of large jumps when the field is applied. First
the scaling behavior of the energy gap between the global energy minimum and
the next lowest minimum of the manifold is considered, by employing exact
ground state calculations and an extreme statistics argument. The scaling has a
logarithmic prefactor originating from the number of the minima in the
landscape, and reads ,
where is the roughness exponent and is the energy fluctuation
exponent of the manifold, is the linear size of the manifold, and is
the system height. The gap scaling is extended to the case of a finite external
field and yields for the susceptibility of the manifolds . We also present a mean field argument
for the finite size scaling of the first jump field, .
The implications to wetting in random systems, to finite-temperature behavior
and the relation to Kardar-Parisi-Zhang non-equilibrium surface growth are
discussed.Comment: 20 pages, 22 figures, accepted for publication in Eur. Phys. J.
Intermittence and roughening of periodic elastic media
We analyze intermittence and roughening of an elastic interface or domain
wall pinned in a periodic potential, in the presence of random-bond disorder in
(1+1) and (2+1) dimensions. Though the ensemble average behavior is smooth, the
typical behavior of a large sample is intermittent, and does not self-average
to a smooth behavior. Instead, large fluctuations occur in the mean location of
the interface and the onset of interface roughening is via an extensive
fluctuation which leads to a jump in the roughness of order , the
period of the potential. Analytical arguments based on extreme statistics are
given for the number of the minima of the periodicity visited by the interface
and for the roughening cross-over, which is confirmed by extensive exact ground
state calculations.Comment: Accepted for publication in Phys. Rev.
Deeply Dissected Tundra Polygons on a Glacio-Fluvial Outwash Plain, Northern Ungava Peninsula, Québec
Deeply dissected tundra polygons are described from the continuous permafrost environment of northernmost Ungava. They are developed on a glacial outwash plain, formed subsequent to déglaciation of the site about 7,500 BP. The exposed surfaces of the polygons are sparsely vegetated and aeolian deflation has removed their sandy matrix material. The furrows between the polygons attain depths of 0.5-2 m. From the base of one. a 0.25 m wide wedge of peat and sandy material penetrates to a minimum depth of 0.7 m (the frost table depth). Radiocarbon dates of 1650 ± 60 BP and 740 ± 80 BP indicate that progressive filling of this fissure accompanied decay of a preexisting ice-wedge. The present low mean annual air temperature at the site ( - 70C) suggests that thawing of the ice-wedges may be related more to local dynamic factors, such as deflation and improved local drainage associated with fluvial dissection, than to regional climatic amelioration. Wedge ice is believed to still underlie the polygon furrows.On décrit ici les polygones de toundra profondément disséqués de la zone de pergélisol continu de l'extrémité nord de l'Ungava. Ils se sont développés sur une plaine d'êpandage fluvio-glaciaire qui s'est formée à la suite de la déglaciation vers 7500 BP. Une végétation rare occupe la surface exposée des polygones et la déflation a emporté la matrice sablonneuse. La profondeur des sillons entre les polygones atteint de 0,5 à 2 m. À la base d'un d'entre eux, on observe une fente large de 0,25 m à remplissage composé de lentilles de tourbe et de sable, jusqu'à au moins 0,7 m de profondeur (front de dégel). Deux datations au 14C de 1650 ± 60 BP et de 740 ± 80 BP montrent que le remplissage progressif de la fissure s'est fait au fur et à mesure de la désintégration d'une fente de gel préexistante. La basse température moyenne annuelle de - 7°C indique que la fonte des fentes de gel dépend davantage de facteurs dynamiques locaux, comme la déflation et un meilleur drainage, qu'à une amélioration du climat. On croit que des fentes de gel occupent encore la partie inférieure des sillons de polygone
Extremal statistics in the energetics of domain walls
We study at T=0 the minimum energy of a domain wall and its gap to the first
excited state concentrating on two-dimensional random-bond Ising magnets. The
average gap scales as , where , is the energy fluctuation exponent, length scale, and
the number of energy valleys. The logarithmic scaling is due to extremal
statistics, which is illustrated by mapping the problem into the
Kardar-Parisi-Zhang roughening process. It follows that the susceptibility of
domain walls has also a logarithmic dependence on system size.Comment: Accepted for publication in Phys. Rev.
Pretibial hematomas – A real-world single-center study
Publisher Copyright: © 2022 The Author(s)We analyzed treatment, outcome, and risk factors for skin necrosis of 60 patients aged ≥65 years treated for a pretibial hematoma in the province of Kymenlaakso, Finland, between 2015 and 2019. Reviewing patients’ medical records revealed two cohorts with distinct trajectories in outcome. By comparing the cohorts, we were able to discover factors associated with the prognosis for generating skin necrosis and the need for operative treatment. Thirty-five (58.3%) patients healed without any management, and 25 (41.7%) patients were treated with hematoma evacuation, mostly for having generated skin necrosis (72%). Among operatively treated patients’ descriptions, such as “parchment skin” and “poor skin quality” were observed frequently (80%) in the medical records. This pathology, dermatoporosis, was statistically significant (p<0.0001) among patients with a complicated outcome of a pretibial hematoma. In addition to dermatoporosis, patients with hematoma evacuation were more fragile having a higher Charlson comorbidity index (p = 0.005), a greater need for a walking aid (p = 0.0002), and overall compromised independency (p = 0.033). Hospitalization and rehabilitation were prolonged in the operatively treated cohort, 6.4 days vs. 2 days, respectively. We recorded a delay in the diagnosis and hematoma evacuation (mean 6, range 0–51 days). In addition, six (10%) patients were misdiagnosed for having erysipelas or deep vein thrombosis indicating that pretibial hematomas are not recognized. Skin quality should be documented, and prompt surgical hematoma evacuation should be executed in fragile patients with dermatoporosis. This could prevent skin necrosis and the further need of wound care or surgical care, long hospitalization, and rehabilitation periods.Peer reviewe
Pretibial lacerations among elderly patients : A province-wide study from Kymenlaakso, Finland, 2015-2019
In this retrospective cohort study, we analysed treatment and outcomes among >= 65-year-old patients who experienced a traumatic pretibial laceration in the province of Kymenlaakso, Finland, between 2015 and 2019. We reviewed computerised medical records for 116 patients with a pretibial laceration, 107 of whom we analysed in further detail. Patients were traced from injury to healing, including rehabilitation periods in health care centres. As expected, the majority of patients were elderly women (67%). Most lacerations were superficial and small, explaining why treatment was mostly conservative. Only 11 (9.48%) patients were treated operatively with surgical debridement or a split-thickness skin graft. The number of overall complications in wounds was high, with a complication rate of 30.2%. Most complications were local wound infections. We found that wound healing took more than 3 months in 32% of patients. Thorough patient tracing revealed numerous follow-up visits and long rehabilitative hospitalisation periods, indicating a significant decline in patient independence and the excessive use of resources. Successful wound healing was eventually observed in 89.66% patients. Furthermore, no terminology regarding pretibial lacerations was found in patient records. This study indicates that pretibial lacerations remain poorly recognised and understood in Finland. (C) 2021 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.Peer reviewe
Seasonal changes in host phenotype manipulation by an acanthocephalan: time to be transmitted?
Many complex life cycle parasites exhibit seasonal transmission between hosts. Expression of parasite traits related to transmission, such as the manipulation of host phenotype, may peak in seasons when transmission is optimal. The acanthocephalan Acanthocephalus lucii is primarily transmitted to its fish definitive host in spring. We assessed whether the parasitic alteration of 2 traits (hiding behaviour and coloration) in the isopod intermediate host was more pronounced at this time of year. Refuge use by infected isopods was lower, relative to uninfected isopods, in spring than in summer or fall. Infected isopods had darker abdomens than uninfected isopods, but this difference did not vary between seasons. The level of host alteration was unaffected by exposing isopods to different light and temperature regimes. In a group of infected isopods kept at 4°C, refuge use decreased from November to May, indicating that reduced hiding in spring develops during winter. Keeping isopods at 16°C instead of 4°C resulted in higher mortality but not accelerated changes in host behaviour. Our results suggest that changes in host and/or parasite age, not environmental conditions, underlie the seasonal alteration of host behaviour, but further work is necessary to determine if this is an adaptive parasite strategy to be transmitted in a particular seaso
Eye fluke-induced cataracts in natural fish populations: is there potential for host manipulation?
Manipulation of host phenotype (e.g. behaviour, appearance) is suggested to be a common strategy to enhance transmission in trophically transmitted parasites. However, in many systems, evidence of manipulation comes exclusively from laboratory studies and its occurrence in natural host populations is poorly understood. Here, we examined the potential for host manipulation by Diplostomum eye flukes indirectly by quantifying the physiological effects of parasites on fish. Earlier laboratory studies have shown that Diplostomum infection predisposes fish to predation by birds (definitive hosts of the parasites) by reducing fish vision through cataract formation. However, occurrence of cataracts and the subsequent potential for host manipulation in natural fish populations has remained poorly explored. We studied the occurrence of eye fluke-induced cataracts from 7 common fish species (Gymnocephalus cernuus, Rutilus rutilus, Leuciscus leuciscus, Alburnus alburnus, Osmerus eperlanus, Coregonus lavaretus and Gasterosteus aculeatus) from the Bothnian Bay in the Baltic Sea. We found that the parasite-induced cataracts were common in fish and they also reached high levels which are likely to predispose fish to predation. However, we observed such cataracts only in species with the highest parasite abundances, which suggests that only certain hosts may be strongly affected by the infectio
Editorial:Identification, risk stratification, and optimized management for Lynch Syndrome
Non peer reviewe
Gullichsen Kairamo Vormala Arkkitehdit Ky:n suunnittelema Paikkatietokeskus toimitalon tarina ja käyttötarkoituksen muutoksen konseptisuunnitelma
Tiivistelmä. Diplomityön aiheena on tarkastella Senaatti-kiinteistöjen omistamaa Maanmittauslaitoksen Paikkatietokeskuksen (Finnish Geospatial Research Institute FGI) vuonna 1995 valmistunutta toimitaloa, Paikkatietokeskusta (ent. Geodeettinen laitos) ja pohtia rakennukselle uutta käyttötarkoitusta. Rakennuksen suunnittelivat Gullichsen Kairamo Vormala (GKV) Arkkitehdit ky, pääsuunnittelijoina Timo Vormala sekä Maaret Pesonen, ja sisustussuunnittelusta vastasi Aulikki Jylhä. Rakennus edustaa vahvasti suunnittelijoidensa arkkitehtonista tyyliä. Paikkatietokeskus jäi tyhjilleen vuoden 2022 alkupuolella, eikä sillä nykyisin ole käyttöä. Se sijaitsee Kirkkonummen Masalassa alueella, jolle kohdistuvassa kaavaehdotuksessa rakennusta suunnitellaan purettavaksi ja sen tilalle kaavaillaan asuinrakennuksia.
Diplomityö rakentuu Paikkatietokeskuksen rakennushistorian taustoittamisesta, uuden käyttötarkoituksen ideoinnista sekä modernin rakennuksen elinkaaren pohtimisesta. Työn alkupuolella tarkastellaan Paikkatietokeskuksen taustaa ja historiaa sekä GKV Arkkitehdit ky:n arkkitehtuuria ja sen ominaispiirteitä. Työn keskivaiheilla keskitytään Paikkatietokeskuksen arkkitehtuuriin ja työn loppupuolella tarkastellaan hypoteettisesta näkökulmasta rakennukselle uutta käyttötarkoitusta sen säilyessä osana uutta asuinaluetta. Millaiseen käyttöön rakennus soveltuisi, kun alkuperäinen käyttötarkoitus on hyvin erityinen? Työssä pohditaan konseptimaisesti erilaisia käyttötarkoituksia, mutta tarkastellaan tarkemmin Paikkatietokeskuksen toimimista osittain päiväkotina. Lopuksi Paikkatietokeskuksen arkkitehtuurin ja purku-uhan kautta pohditaan modernin rakennuksen elinkaarta sekä korjaamiseen liittyviä haasteita.
Tavoitteena diplomityössä on ollut esitellä rakennus ja sen arkkitehtuuri sekä määrittää rakennuksen arvot. Lisäksi konseptisuunnitelman avulla tavoitteena on ollut osoittaa, että korjaustarpeista ja -haasteista huolimatta rakennuksella olisi edellytykset tarjota tilat toisenlaiselle käyttötarkoitukselle purkamisen sijaan. Rakennus ei täytä aikaan perustuvia suojelukriteerejä, mutta on arkkitehtonisen tyylinsä sekä hiilijalanjäljen näkökulmasta erityisen nuori purettavaksi.Finnish Geospatial Research Institute building by Gullichsen Kairamo Vormala Arkkitehdit Ky The story of the office building and a consept level plan transforming the original function. Abstract. This master’s thesis researches the Finnish Geospatial Research Institute (FGI) building (former Geological Institute building) and suggests a new function for the building on a concept level. The FGI research and office building of the National Land survey of Finland is owned by Senat properties and was built in 1995. The building was designed by Gullichsen Kairamo Vormala (GKV) Arkkitehdit ky, with Timo Vormala and Maaret Pesonen as principal architects. Aulikki Jylhä was responsible for interior design. The architecture of the building strongly represents the designers’ architectural style. At the beginning of the year 2022, the Geospatial research building emptied of employees and it hasn’t been used since. The location of the building is in Masala, Kirkkonummi, and a new town plan is in process for the location. Land-use planning proposes housing to replace the FGI building.
The master’s thesis consists of research of the background of the Geospatial research building, ideas for a new function of use, and reflection on the life cycle of the modern building. The first part focuses on studying the background and the history of the FGI building in addition to studying the architecture and characteristics of the GKV Arkkitehdit ky firm. The focus in the middle part is to study the architecture of the FGI building. The thesis later focuses on a hypothetical point of view for the new function for the building as a part of the new housing area. What kind of use could be applied to the building when the former use has been so unique? Various ways to change the function of the building are considered in the thesis on a concept level, but the focal point proposes the building partially function as a day-care centre. The end of the thesis is about the life cycle of a modern building and about the challenges of renovating modern architecture.
The target for the thesis has been to present the building, its architecture and define its values. In addition, the concept plan is made to show that even if there are many needs and challenges renovating the building, it has potential to offer space for new functions and the building could have a different future to being demolished. The building doesn’t meet the age related criteria of protection but from an architectural and environmental point of view it is remarkably young to be demolished
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