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Experience of the surgeon affects the success rate of the placement of orthodontic miniplates
No full textBackground: Skeletal Class III patients can be treated with bone anchored maxillary protraction (BAMP) treatment. The placement of miniplates is an invasive operation and needs to be carried out under general anesthesia. Aim: The aim of this retrospective study was to determine the failure rate of miniplates. Methods: All the patients who had miniplates placed for BAMP treatment between January 2010 and April 2020 in Department of Oral and Maxillofacial Diseases, Helsinki University Hospital, Finland were included in this study. The patient records were retrospectively screened. The success rate of the placement of orthodontic miniplates was evaluated between surgical residents (Group 1) and consultant surgeons (Group 2). Materials: The study group consisted of 164 miniplates in 42 patients. The miniplates were divided into two groups, depending on the placement operator. Group 1 consisted of 86 miniplates placed by surgical residents. Group 2 consisted of 78 miniplates placed by consultant surgeons. Results: In Group 1 (11 females, 14 males) and Group 2 (16 females, 9 males). The overall failure rate of miniplates was 23.8% (n = 39). The failure rate for surgical residents (Group 1) was 31.4% (n = 27) and for consultant surgeons (Group 2), 15.3% (n = 12) (p < 0.05). Out of all the failed miniplates 69.2% (n = 27) were placed by residents and 30.8% (n = 12) by consultants. Limitations: This retrospective study consisted of a limited number of patients. Conclusion: The failure rate of miniplates placed by consultant surgeons was lower compared to surgical residents (p < 0.05).Peer reviewe
Varhainen Syyrian kirkko ja juutalaisuus : Juutalaisvastaisuus Afrahat Persialaisen Viisaan opetuksissa
No full textTutkin varhaisen Syyrian kirkon suhdetta juutalaisuuteen 300-luvun alun Persian
valtakunnassa käyttäen Afrahat Persialaisen Viisaan opetuksia lähteenäni. Tarkennun
Afrahat Persialaisen opetuksissa ilmenneeseen juutalaisvastaisuuteen ja sen ilmenemisen
syihin.
Syyrian kirkko haki 300-luvun alussa muotoaan omana kirkkonaan irrallaan Rooman
valtakunnassa vaikuttaneesta kristinuskosta. 300-luvulla Syyrian kirkko oli nuori ja vasta haki
omaa suuntaansa sekä uskonnollisen identiteetin että teologisen kehityksensä puolilla.
Afrahatin 23:ssa opetuksessa on havaittavissa selkeästi tällaista oman identiteetin hakemista
tekemällä eroa juutalaisuuteen. Afrahatin kirjoitukset ja elämä asettuvat aikaan, jolloin
juutalaiskristillisistä tavoista tahdotaan päästä eroon, luoden omaa uskonnollista identiteettiä
kristittynä niin sanottujen ”pakanakristittyjen” johdolla, eli sellaisten kristittyjen, jotka ovat
kääntyneet kristinuskoon juutalaisuuden ulkopuolella.
Opetukset ovat yhden Syyrian kirkon vaikuttavimman teologin aikaansaannosta.
Afrahat eli vuosien n. 270–345 välillä. Hän oli kristitty, askeetti ja äärimmäisen arvostettu
uskonnollinen opettaja ja ohjaaja, joka nautti vahva uskonnollista auktoriteettia oman
kirkkonsa parissa. Afrahatin opetuksista paistaa vahva argumentaatio kristinuskon
emouskontoa, juutalaisuutta, vastaan. Tarve erottautua juutalaisuudesta näkyy läpi
opetusten, kun Afrahat perustelee juutalaisten uskonnollisten tapojen turhuutta samalla
puolustaen kristinuskolle tärkeitä hyveitä. Afrahat ei ole ainoa kristitty teologi, joka käy
sanasotaa juutalaisia rabbeja vastaan, vaan hän asettuu yhtenäiseen rintamaa muiden
aikalaistensa kanssa juutalaisten rabbien muodostamaa rintamaa vastaan. Afrahat
Persialainen antaakin ainutlaatuisen katsauksen Syyrian kirkon opillisiin, ja järjestyksellisiin
kysymyksiin, ja omaa tutkielmaani ajatellen, hän antaa erittäin selkeän viestin Syyrian kirkon
suhtautumisesta lähialueidensa juutalaisiin. Afrahatin asema syyrialaisen seurakunnan
keskuksessa luo opetuksille arvovaltaisen aseman uskonnollisina opetusteksteinä,
kirkkojärjestyksenä ja ohjeina, joiden mukaan hänen aikalaisten kristittyjen olisi oikein elää.
ja toimia.
Päädyn tutkimuksessani lopputulokseen, että kristinusko ja juutalaisuus olivat
äärimmäisen kilpailullisia keskenään Persian valtakunnassa jo 300-luvulla. Rabbiinisen
juutalaisuuden saapuminen Mesopotamiaan 200-luvulla sai aikaan uskontojen välisen
teologisen kamppailun, joka jatkui kiivaana vielä 300-luvulla ja sen jälkeen. Afrahatin
opetuksissa ilmenevä retoriikka viestii sekä huolesta että katkeruudesta. Huoli nousee oman
seurakuntansa pysymisestä kristinuskossa vainojen keskellä ja katkeruus nousi juutalaisten
erityisasemasta Persian valtakunnassa. Afrahatille, kuten kenelle tahansa muulle
uskonnolliselle johtajalle, pahin painajainen olisi menettää seurakuntansa jollekin toiselle
uskonnolle. Katkeruus juutalaisten erityisasemasta nousi jalustalle kristittyjen kärsiessä
vainoista, jotka alkoivat 337, kun taas juutalaiset nauttivan asemastaan jopa Persian
valtakunnan valtion virkamiehinä. Afrahatin ja samalla Syyrian kirkon suhtautuminen
juutalaisuuden on äärimmäisen torjuvaa
From Bank Runs to CBDC: The Evolution and Applications of the Diamond-Dybvig Model
No full textThis literature review examines how the Diamond-Dybvig (DD) model has been used to explain the benefits and risks of banking. The DD model illustrates how banks transform illiquid investments into liquid deposits, improving household welfare. However, the model also shows that this banking practice makes banks vulnerable to bank runs.
The thesis reviews how this influential model has been criticized and extended over time. It also explores how the DD model has been used to study the effects of central bank digital currencies (CBDC). This is done by analyzing four DD-based models in which CBDC is integrated into the framework. The DD model is applied in these four cases because it provides useful framework for analysing how CBDC, by potentially reducing deposits, influences the efficiency and stability of the banking system.
Additionally, the thesis assesses how well the DD model is suited for analyzing CBDC's effects and what limitations its use may have. For example, the models do not fully consider factors such as the ease of payments or the role of cash as a precautionary asset, both of which influence consumers' choices regarding how they hold and use their funds. Furthermore, the study notes that the models do not take into account deposit insurance scheme, which is an essential part of the original DD model and modern banking systems.Tässä kirjallisuuskatsauksessa käydään läpi, miten Diamond-Dybvig-mallia on hyödynnetty pankkitoiminnan hyötyjen ja haittojen selittämisessä. DD-malli havainnollistaa, kuinka pankit muuttavat epälikvidejä sijoituksiaan likvideiksi talletuksiksi ja siten parantavat kotitalouksien hyvinvointia. Lisäksi DD-mallissa huomataan, että tämä pankkien toimintamalli altistaa ne talletuspaoille.
Tutkielmassa käydään läpi, miten tätä vaikutusvaltaista mallia on ajan saatossa kritisoitu ja laajennettu. Lisäksi katsauksessa tarkastellaan, miten DD-mallia on hyödynnetty digitaalisten keskuspankkirahojen (CBDC) vaikutusten tutkimisessa. Tämä tehdään käymällä läpi neljää DD-pohjaista mallia, joissa CBDC on integroitu osaksi viitekehystä. DD-mallia on hyödynnetty näissä neljässä mallissa, sillä sen avulla voidaan mallintaa, miten CBDC:n talletuksia mahdollisesti vähentävä vaikutus voi muovata pankkijärjestelmän tehokkuutta ja vakautta.
Tutkielmassa arvioidaan lisäksi sitä, miltä osin DD-malli soveltuu CBDC:n vaikutusten tutkimiseen ja millaisia rajoitteita sen käyttöön liittyy. Tutkielmassa esimerkiksi havaitaan, että mallit eivät ota laajasti huomioon tekijöitä, kuten maksamisen helppoutta tai käteisen merkitystä varautumistarkoituksessa, mitkä vaikuttavat kuluttajien valintaan siitä, missä muodossa he haluavat käyttää tai säilyttää varojaan. Lisäksi tutkielmassa huomataan, että mallit eivät huomioi talletussuojajärjestelmää, joka on tärkeä osa alkuperäistä DD-mallia ja nykyisiä pankkijärjestelmiä
Enhancing Optoelectronic Properties in Phthalocyanine-Based SURMOFs : Synthesis of ABAB Linkers by Avoiding Statistical Condensation with Tailored Building Blocks
No full textPhthalocyanine (PC)-based metal-organic frameworks (MOFs) hold substantial promise for applications in energy storage, sensing, and catalysis due to their robust stability and enhanced electron transfer capabilities. However, synthesizing phthalocyanine linkers with precise geometries presents a significant challenge, which limits their prevalence in the field. Traditional methods typically employ readily synthesized tetratopic PC linkers for realizing PC-based MOFs. In response, the study presents an innovative approach using ditopic ABAB-phthalocyanine MOF linkers. The A and B building blocks in PC synthesis are deliberately designed to circumvent issues of statistical condensation. These PC linkers are then utilized in the fabrication of zinc-based surface-anchored MOF (SURMOF) thin films. The structural and electronic properties of these SURMOFs are explored through a series of detailed experimental and computational methods, including X-ray diffraction, scanning electron microscopy (SEM), and density functional theory (DFT) calculations. UV-Vis spectroscopy reveals significant improvements in electronic absorption, thereby enhancing the material's performance in light harvesting and energy conversion. Furthermore, a photodetector built with this novel linker demonstrates high efficacy in the long-wavelength region (780 nm), highlighting its potential for cutting-edge sensing technologies.Peer reviewe
Repulsive interatomic potentials calculated at three levels of theory
No full textThe high-energy repulsive interaction between nuclei at distances much smaller than the equilibrium bond length is the key quantity determining the nuclear stopping power and atom scattering in keV and MeV radiation events. This interaction is traditionally modeled within orbital-free density functional theory with frozen atomic electron densities, following the Ziegler-Biersack-Littmark (ZBL) model. In this work, we calculate atom pair-specific repulsive interatomic potentials with the ZBL model, and compare them to two kinds of quantum chemical calculations (second-order Møller-Plesset perturbation theory in flexible Gaussian basis sets as well as density functional theory with numerical atomic orbital basis sets) which go well beyond the limitations in the ZBL model, allowing the density to relax in the calculations. We show that the repulsive interatomic potentials predicted by the two quantum chemical models agree within ∼1% for potential energies above 30 eV, while the ZBL pair-specific potentials and universal ZBL potentials differ much more from either of these calculations. We provide pair-specific fits of the screening functions in terms of three exponentials to the calculations for all pairs Z1-Z2 for 1 < Zi < 92, and show that they agree within ∼2% with the raw data. We use these potentials to simulate ion implantation depth profiles in single-crystalline Si and show very good agreement with experiment. However, we also show that under channeling conditions, the attractive part of the potential can affect the depth profiles.Peer reviewe
Carbon allocation to roots of suppressed Norway spruce increases immediately after selection harvest
No full textSelection harvesting in fertile, drained peatlands is an alternative for even-aged forestry, where clearcutting takes place at the end of each rotation period. Avoiding clear-cuts has been promoted due to reducing negative externalities, like nutrient loading to waterways and significant greenhouse gas emissions after harvesting. Our aim was to understand the responses of suppressed Norway spruce trees to selection harvesting. We analysed biomass accumulation and priorities of carbon allocation to stems, proximal roots and distal roots. We quantified carbon isotope composition (delta 13C) and cross-sectional growth of proximal (supporting) roots and distal (water and nutrient transportation) roots. The study took place in a drained, fertile boreal peatland site in southern Finland, where a selection harvest was conducted in 2016, while an area as a control was left untouched. Our results show that suppressed Norway spruce trees increased their cross-sectional growth of proximal roots and distal roots twice as much as that of the stem during the first five years after the selection harvest. The timing and magnitude of carbon allocation to proximal roots and distal roots were immediate and equal, underlining the fact that trees were investing in mechanical support and nutrient and water uptake. These results show that the climate benefits of selection harvest were not delayed. Instead of immediate growth of stems, we found immediate growth of roots.Peer reviewe
Change in functional profile after lumbar spinal surgery : a register-based study among 1,451 patients
No full textBackground and purpose - The Oswestry Disability Index has usually only been used as a composite score but, according to previous studies, disability caused by back pain may be too broad a concept to be explained by a single number. We aimed to analyze changes in each ODI item's score from preoperative to 3, 12, and 24 months after surgery by creating a functional profile. Methods - This was a register-based study of 1,451 patients undergoing lumbar spinal surgery between 2018 and 2021. The patients responded to a repeated survey preoperatively and 3, 12, and 24 months after surgery. The significance of change in the ODI items' scores was assessed by a symmetry test. Results - All the ODI items' scores and total score improved between baseline and 3-month follow-up (P < 0.001). The magnitude of this improvement varied across different items. After 3 months, no significant change was seen for most of the items. Conclusion - During a postoperative 2-year follow-up, individual items of the ODI demonstrated changes of different magnitude. The results imply that the use of a single composite score of the ODI might be insufficient to describe changes in functioning among patients undergoing lumbar spinal surgery. Instead, in some situations, creating a functional profile based on the scores from individual items may be a better solution to describe the changes in disability level.Peer reviewe
Projected changes of the emission and transport of organic pollutants and metals from shipping in European seas 2018–2050
No full textThe ChemicalDrift model is applied to predict concentrations of metals and polycyclic aromatic hydrocarbons emitted from shipping in European seas in 2050, compared to 2018. Sources include antifouling paints (AFPs), discharge water from scrubbers and atmospheric deposition. The fate of pollutants in the marine environment is presented, highlighting the effect of degradation and volatilization, with seasonal and regional differences. A simplified impact assessment is outlined, where predicted environmental concentrations of individual chemicals and whole effluent concentrations of scrubber discharge water are compared to predicted no-effect concentrations (PNECs) or lowest observed effect concentration (LOEC). The 2018 assessment shows scrubber effluent concentrations exceeding LOEC in Baltic and North Sea coastal regions. By 2050, assuming high use of scrubbers, elevated concentrations may extend to all European seas. For AFPs, assuming continued use of primarily copper-based paints, the highest copper concentrations are projected in 2050 for North Sea ports and coasts, potentially exceeding PNECs
A phenomenographic study of teachers' perspectives on digital competence: Challenges and opportunities
No full textSyftet med denna forskning är att återge lärares perspektiv och uppfattningar om begreppet digital kompetens och vad de ser för möjligheter och utmaningar i att stödja elever att utveckla digital kompetens. Begreppet digital kompetens är mycket omfattande och komplext och förändras också tillsammans med hur vårt digitala samhälle utvecklas. Det levande begreppet skapar behov för att kontinuerligt omdefiniera det. Användning av digitala verktyg i skolmiljö har blivit ett samtalsämne i en bredare samhällsdiskurs där en del anser att användning strängt bör begränsas. Samtidigt behöver elevers digitala kompetens utvecklas för att kunna navigera de digitala miljöer de rör sig i för akademiskt syfte och i vardagen. Tidigare forskning har visat att elevers användande av digitala verktyg utanför skolan inte bidrar till färdigheter för att använda digitala verktyg i studiesyfte. Genom att ge lärarnas perspektiv på digital kompetens och vad de anser elever behöver utveckla för färdigheter samt vad som möjliggör eller utmanar dem i deras lärarskap bidrar denna studie med viktiga delar som kan stärka elevers digitala kompetens genom att eliminera de hinder som kan uppstå.
Detta är en kvalitativ studie med en fenomenografisk ansats. Empirin består av intervjuer med sex lärare från två olika skolor och kommuner i Helsingforsregionen. Analysen har sedan genomförts i fem faser där det slutliga resultatet består av de beskrivningskategorier som representerar skillnader och variationer i lärarnas uppfattningar.
De finlandssvenska lärare som intervjuats beskriver många olika delar av begreppet digital kompetens. Flera av delarna har starka kopplingar till läroplanens formulering samt de större ramverk som beskriver digital kompetens. Lärarna bidrar dock med nyanser då beskrivningarna är mer lämpliga för grundskolan exempelvis beskrivs kunskaper om de mekaniska funktionerna hos en dator och hur elevers motorik behöver övas för att kunna använda de digitala verktygen. För att lärarna på bästa sätt ska kunna stödja elevers utveckling av digital kompetens behöver de adekvat tillgång till datorer och hårdvara, IKT-support på skolan, en närvarande och tillgänglig IKT-plan, väl organiserad kompetensutveckling och goda egenskaper så som tålamod och nyfikenhet. På så sätt skapas möjligheter för digitala kompetens och utmaningarna begränsas.The purpose of this research is to present teachers' perspectives and perceptions of the concept of digital competence and to explore the opportunities and challenges they see in supporting students to develop digital competence. The concept of digital competence is extensive and complex, evolving alongside the development of our digital society. This dynamic concept necessitates continuous redefinition. The use of digital tools in the school environment has become a topic of broader societal discourse, with some advocating for strict limitations on their use. Simultaneously, students need to develop digital competence to navigate the digital environments they encounter for academic purposes and in everyday life. Previous research has shown that students' use of digital tools outside of school does not contribute to the skills needed to use digital tools for academic purposes. By providing teachers' perspectives on digital competence and what they believe students need to develop in terms of skills, as well as what enables or challenges them in their teaching, this study contributes important insights that can enhance students' digital competence by eliminating potential barriers.
This is a qualitative study with a phenomenographic approach. The empirical data consists of interviews with six teachers from two different schools and municipalities in the Helsinki region. The analysis was conducted in five phases, resulting in descriptive categories that represent differences and variations in the teachers' perceptions.
The Finland-Swedish teachers interviewed describe many different aspects of the concept of digital competence. Several aspects are strongly linked to the curriculum's formulation and the larger frameworks that describe digital competence. However, the teachers add nuances as their descriptions are more suitable for primary education, such as knowledge of the mechanical functions of a computer and how students' motor skills need to be practiced to use digital tools. To best support students' development of digital competence, teachers need adequate access to computers and hardware, ICT support at the school, a present and accessible ICT plan, well-organized professional development, and personal qualities such as patience and curiosity. In this way, opportunities for digital competence are created, and challenges are limited
Betula pendula Roth. survival and growth in treeline is affected by genotype and environment
No full textAlpine and Arctic treelines are assumed to be shifting toward higher latitudes and altitudes as a consequence of climate warming. Here, we compared the survival and growth of 1264 silver birch (Betula pendula Roth.) trees representing nine half-sib families. The trees were planted in two arboreta situated in distinct altitudinal environments in northern Finland in 1976 and 1977. The arboreta were located 9 km from each other and approximately 60 km north from the species' most northern natural growth site at that time. They were fenced to prevent vertebrate grazing, which is known to be among the most important factors limiting the expansion and regeneration of forests in European treeline ecotones. Overall, 90% and 81% of the trees were alive five and 40 years after planting in the two arboreta, respectively. Survival of trees varied among the half-sib families, especially in Arboretum 1, situated in a lower altitudinal environment characterized by soils with lower levels of nutrients, a longer growing season, and harsher winter temperatures. Trees were distinctively bigger in Arboretum 2: 50% taller (6.2 m vs. 4.4 m) and 68% thicker (9.5 cm vs. 5.6 cm) compared to trees in Arboretum 1. Furthermore, the performance of half-sib families varied depending on the garden they were grown in. These results demonstrate that the acclimation capacity of B. pendula allows its distribution to expand north from the present range; however, local abiotic environmental conditions (soil fertility and winter temperatures) and other selection pressures (herbivory) are likely to affect the genetic structure and growth of B. pendula populations.Peer reviewe