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Cytotoxicity of β-Cyclodextrins in Retinal Explants for Intravitreal Drug Formulations
Get PDFCyclodextrins (CDs) have been widely used as pharmaceutical excipients for formulation purposes for different delivery systems. Recent studies have shown that CDs are able to form complexes with a variety of biomolecules, such as cholesterol. This has subsequently paved the way for the possibility of using CDs as drugs in certain retinal diseases, such as Stargardt disease and retinal artery occlusion, where CDs could absorb cholesterol lumps. However, studies on the retinal toxicity of CDs are limited. The purpose of this study was to examine the retinal toxicity of different beta-(β)CD derivatives and their localization within retinal tissues. To this end, we performed cytotoxicity studies with two different CDs—2-hydroxypropyl-βCD (HPβCD) and randomly methylated β-cyclodextrin (RMβCD)—using wild-type mouse retinal explants, the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and fluorescence microscopy. RMβCD was found to be more toxic to retinal explants when compared to HPβCD, which the retina can safely tolerate at levels as high as 10 mM. Additionally, studies conducted with fluorescent forms of the same CDs showed that both CDs can penetrate deep into the inner nuclear layer of the retina, with some uptake by Müller cells. These results suggest that HPβCD is a safer option than RMβCD for retinal drug delivery and may advance the use of CDs in the development of drugs designed for intravitreal administration.This work was financially supported by the European Union grant no. MSCA-ITN-2017-
765441 (transMed); the German Research Council (DFG) grant no. PA1751/10-1; and the Faculty of
Pharmaceutical Sciences, University of IcelandPeer Reviewe
Modeling of Hydrogen Production by Applying Biomass Gasification: Artificial Neural Network Modeling Approach
Get PDFIn order to accurately anticipate the proficiency of downdraft biomass gasification linked
with a water–gas shift unit to produce biohydrogen, a model based on an artificial neural network (ANN) approach is established to estimate the specific mass flow rate of the biohydrogen output of the plant based on different types of biomasses and diverse operating parameters. The factors considered as inputs to the models are elemental and proximate analysis compositions as well as the operating parameters. The model structure includes one layer for input, a hidden layer and output layer. One thousand eight hundred samples derived from the simulation of 50 various feedstocks in different operating
situations were utilized to train the developed ANN model. The established ANN in the case of product biohydrogen presents satisfactory agreement with input data: absolute
fraction of variance (R2) is more than 0.999 and root mean square error (RMSE) is lower than 0.25. In addition, the relative impact of biomass properties and operating parameters on output are studied. At the end, to have a comprehensive evaluation, variations of the inputs regarding hydrogencontent are compared and evaluated together. The results show that almost all of the inputs show a significant impact on the smhydrogen output. Significantly, gasifier temperature, SBR, moisture content and hydrogen have the highest impacts on the smhydrogen with contributions of 19.96, 17.18, 15.3 and 10.48%, respectively. In addition, other variables in feed properties, like C, O, S and N present
a range of 1.28–8.6% and proximate components like VM, FC and A present a range of 3.14–7.67% of impact on smhydrogen.This paper was a part of the project funded by Icelandic Research Fund (IRF), (in Icelandic: Rannsoknasjodur) and the grant number is 196458-051
Synthesis of Tripeptides, Pd(II) and Ni(II) Complexes and their Potential Use in Activation of Small Molecules
Get PDFNotkun verndarhópa á virka hópa aminosýra í litlum peptíðum gefur tækifæri til að breyta girðieiginleikum viðkomandi peptíðs við málmjónir. Alkýlun á karboxýlhóp C-enda peptíðsins beinir girðingu málmjónarinnar í fjórgirta κ4[NH2,N,N,=O] komplexa. Með stýringu á samsetningu peptíðsins er hægt að mynda kelaða hringi umhverfis málmjónina í misstórum hringjastærðum; Hægt er að mynda fjórgirðandi peptíð, κ4[n,5,5] (þar sem n = 5, 6, 7, eða 8 atóm) með misstórum hringjum á hliðarkeðju N-endans sem leiðir til mismunandi rúmfræðilegrar girðingar málmsins og væntanlega breytilegra efnaeiginleika. Fjögur trípeptíð með alkýlaða karboxylhópa voru smíðuð, α-Asp(OtBu)AlaGly(OMe), β- Asp(OtBu)AlaGly(OMe), TrpAlaGly(OMe), HisAlaGly(OMe), og γ-Glu(OMe)Cys(SMe)- Gly(OMe) til þess að mynda palladium og nickel komplexa í fjórgirtu umhverfi.
Girðieiginleikar alkýleraðra trípeptíða voru rannsakaðir með spennutítrunum og NMR mælingum í vatni. Sýrustigsháð girðing tenglanna við [Pd(en)(H2O)2]2+ var greind og myndaðir komplexar staðfestir með NMR greiningum. Út frá þessum niðurstöðum voru tilraunir hannaðar til að smíða Pd(II) komplexa með trípeptíðunum α- Asp(OtBu)AlaGly(OMe), β-Asp(OtBu)AlaGly(OMe), og TrpAlaGly(OMe). Þessir komplexar voru einangraðir og greindir að fullu. Tenglarnir mynda þrí- og fjórgirta komplexa með Pd(II). Þrígirtu komplexarnir höfðu fjórða tengilinn frá upphafsefninu. Skiptihvörf á þessum fjórða tengli sýndu að hægt væri að fjarlægja rétt valinn tengil og trípeptíðið myndaði þá fjórgirt lokaefni með ferningslaga byggingu. Byggingar komplexanna voru reiknaðar með DFT reikningum þar sem kristalbyggingar fengust ekki. Hvarfgirni með litlum sameindum eins og ethylen, sýrum, formati, og episúlfíði var skoðuð, en komplexarnir hvörfuðust ekki við ethylene. Þeir brotna niður í sýru og við súrar aðstæður. Asetaldehýð myndaðist í hvarfi við ethylene við súrar aðstæður. Pd(II) er mjúk Lewis sýra og myndar auðveldlega súlfíð; Pd-trípeptíð komplexarnir tóku auðveldlega brennistein frá episúlfíði og mynduðu alken við hvötunaraðstæður. Hvarf við format leiddi til rof málmsins frá tenglinum og afoxun í Pd(0).
Ni(II) komplexar með tenglunum, α-Asp(OtBu)AlaGly(OMe), β-Asp(OtBu)AlaGly(Ome), og TrpAlaGly(OMe) voru smíðaðir og greindir með litrófsgreiningum, frumefna og massagreiningum. Komplexarnir hafa bjagaða ferningslaga byggingu samkvæmt DFT reikningum. Alkýlhópar tenglanna reyndust viðkvæmari fyir sýrustigi í hvörfum með Ni(II) en með Pd(II) og C-endi trípeptíðsins gekkst undir vatnsrof við mildar aðstæður. Rafefnafræði komplexanna var mæld í vatni og sýndi óafturkræfa hegðun fyrir alla þrjá komplexa.The use of protecting groups on amino acid and peptides affords opportunities to change preferred coordination behaviors to metal centers. Alkylating the C-terminus carboxylate allows directed tripeptide coordination, forming tetradentate κ4[NH2,N,N,=O] complexes. Changing tripeptide composition enables the formation of chelates of various ring sizes, and depending on the N-terminus side chains, tetradentate κ4[n,5,5] (where n = 5, 6, 7, or 8 membered rings) coordination geometries can be achieved.
The alkylated tripeptide compounds α-Asp(OtBu)AlaGly(OMe), β-Asp(OtBu)Ala- Gly(OMe), TrpAlaGly(OMe), HisAlaGly(OMe), and γ-Glu(OMe)Cys(SMe)Gly(OMe) were synthesized as ligands to coordinate to palladium and nickel to form neutral tetradentate complexes. The coordination of select alkylated tripeptides to palladium was first established by potentiometric and NMR spectroscopic data. pH-dependent complexation was analyzed and coordination properties to [Pd(en)(H2O)2]2+ were inferred from their NMR spectra. Building on aqueous NMR studies, Pd(II) complexes with the tripeptides α-Asp(OtBu)- AlaGly(OMe), β-Asp(OtBu)AlaGly(OMe), and TrpAlaGly(OMe) were synthesized and characterized. The ligands form tri- and tetradentate complexes with Pd(II). For tridentate coordination complexes, ligand exchange reactions, occupying the fourth coordination sphere, showed that sufficiently labile ligands may be removed to form the tetradentate coordination mode, which adopt a square planar geometry with tetradentated ligands. The complex coordination geometry was established using 1H and 13C NMR, and infrared spectroscopy, and supported using DFT calculations. Reactivity of palladium tripeptide complexes with small molecules such as ethylene, acids, CO and formates, and episulfides were investigated. Complexes were found to be rather inert towards ethylene coordination and decompose in acid and under acidic conditions; in the presence of ethylene, acetaldehyde was formed only after complex decomposition. Reactivity with CO and CO surrogates such as formates results in the dissociation of the ligand and reduces the metal to Pd(0). Pd(II) is a soft Lewis acid and thiophilic; when reacted with thiirenes, Pd-tripeptide complexes abstracted sulfur from the episulfide at modest catalytic rates.
Ni(II) complexes with the ligands, α-Asp(OtBu)AlaGly, β-Asp(OtBu)AlaGly, and TrpAlaGly were synthesized and characterized using infrared and 1H, 13C NMR spectroscopy, mass spectrometry and elemental analysis. The complexes were predicted using DFT calculations to have square planar geometries. The esters of these ligands proved highly pH sensitive and hydrolyze fully at moderately basic conditions. The electrochemistry of the complexes was investigated in water to reveal irreversible redox behavior of all three complexes
Electrodeposition of aluminium-titanium alloys from molten fluoride-oxide electrolytes
Get PDFPublisher's version (útgefin grein)This study reports the direct production of an aluminium-titanium alloy during aluminium electrolysis in fluoride-based melts. Experiments were conducted in a laboratory cell dedicated to current efficiency mea-surements. The temperature was varied from 960 to 980 ◦C at a cathodic current density (CCD) of 0.9 A/cm2 and a cryolite ratio (CR) of 2.2. The titanium content was up to 1.0 wt%. Titanium was added in the form of a TiO2 precursor. Bath samples were collected regularly and analyzed with ICP-MS to observe the decay of titanium during electrolysis. The current efficiency for electrodeposition of Al–Ti alloys was estimated to be at least around 90%. The surface of the solidified metal deposits was mostly flat, but some deposits were partially deformed.Norges Teknisk-Naturvitenskapelige UniversitetPeer reviewe
Perceptions and Attitudes of Correctional Staff Toward ADHD—A Challenging Disorder in Everyday Prison Life
Get PDFPublisher's version (útgefin grein)Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that is associated with risk-taking behaviors, poor self-control, and interpersonal difficulties. Affected individuals have an increased probability of involvement with the criminal justice system, contributing to a higher rate of arrest, and imprisonment compared with the general population; they are also inadequately treated once sentenced. Because prison staff play a central role in the identification of inmates with mental disorders, they could well be key to improving provision of care. There is however little knowledge of the conceptions, perceptions, and attitudes of prison staff toward ADHD. Such information could help to identify starting points for awareness training and further implementation of specific ADHD treatment. To bridge this gap, we undertook a study based on a qualitatively-driven mixed methods design, combining qualitative data collection in the form of narrative interviews with 19 prison staff from a Swiss correctional facility with quantitative data collection in the form of a survey that included the Attitudes toward Prisoners scale. The interviews were analyzed with QSR NVIVO 11 and a qualitative content analysis approach was used to evaluate findings. Prison staff were generally aware of ADHD and its symptomology, believing it to a be "real," but "fashionable" disorder and favoring hereditary-genetic or biological explanatory models for its development. They viewed inmates with ADHD rather negatively, as complicating correctional efforts, and perceived them as sticking out, as tying up more resources and as frequently being involved in confrontations. Our findings suggest that difficulties in pragmatic aspects of communication and language comprehension may be perceived "as not listening or following instructions," creating additional tensions. Consequently, inmates with ADHD are more often exposed to disciplinary sanctions, such as solitary confinement-an intervention deemed "necessary" by staff. Therefore, staff training on ADHD might need to cover evidence on adverse effects. Non-pharmacological interventions for treatment were preferred and considered to be highly efficacious. Skepticism toward pharmacological treatment prevailed, even when benefits from stimulant medication were described. Interestingly, this skepticism was not the result of negative experiences with the misuse and diversion of stimulants. Acceptance of multimodal treatment among prison staff may require customized strategies.Peer reviewe
Keratinocyte carcinoma in Iceland: Epidemiology and risk in association with medication
Get PDFVitað er að mikil aukning hefur verið á grunnfrumu og flöguþekjumeinum í
húð síðustu ár í vestrænum löndum en ekki er alveg skýrt hvers vegna svo er.
Helstu áhættuþættir þessara meina eru ljós húð og útfjólublá geislun, og einnig
hafa sum lyf verið bendluð við aukina áhættu með því að valda ónæmisbælingu
eða auknu næmi fyrir útfjólublárri geislun í húð. Ekki er mikið til af rannsóknum
sem skoða faraldsfræði og áhættuþætti þessara húðmeina, og það er óljóst
hvort sum þessara lyfja sem auka þessa áhættu myndu gera það á Íslandi þar
sem er lítil útfjólublá geislun miðað við flest önnur lönd. Helstu markmið
þessarar rannsóknarar var að athuga sérstaklega tíðni þessara meina á Íslandi
og einnig skoða hvaða áhrif ákveðin lyf gætu verið að hafa á áhættu íslendinga
að fá þessi mein. Við skoðuðum sérstaklega hydrochlorothiazide (HCTZ),
TNF-alpha hindra og statín, sem hafa í sumum rannsóknum verið bendluð við
aukna áhættu á húðmeinum. Einnig þá skoðuðum við hugsanleg tengsl
metformin við húðmein, en metformin hefur sýnt að lækki áhættu á
krabbameinum í sumum rannsóknum. Gagnagrunnur hjá krabbameinsskrá var
notaður til þess að reikna tíðnitölur, og var lyfjagrunnur landlæknisembættis
notaður til þess að skoða tengsl við lyf. Niðurstöður okkar sýndu að þrátt fyrir
það að útfjólublá geislun á Íslandi sé lág hefur tíðni grunn- og flöguþekjumeina
aukist til muna, og Ísland er eina landið þar sem að tíðni grunnfrumumeins og
grunns flöguþekjumeins er hærra í konum heldur en körlum. Þetta kann að
skýrast af því konur virðast vera líklegri til þess að nota ljósabekki og stunda
sólböð þegar þær eru erlendis heldur en karlmenn. Karlmenn vinna oftar úti
heldur en konur en erlendis þá eru þeir því í hárri áhættu að fá húðkrabbamein
vegna mikillrar geislunar. Á Íslandi er þessi geislun heldur minni. Einnig sáum
við að þessi aukning á húðmeinum er mest á búk og fótleggjum kvenna, sem
bendir enn frekar til ljósabekkja eða sólarlandafera sem orsök. Varðandi lyf, þá
var HCTZ tengt við aukna áhættu á bæði grunn- og flöguþekjuæxlum. HCTZ
eykur næmi fyrir útfjólubláum geislum og því var ekki endilega viðbúist að lyfið
auki áhættu í landi með svo litla bakgrunns geislun. TNF-alpha hindrar og
statín voru bæði tengt við aukna áhættu á flöguþekjumeinum, en ekki
grunnfrumukrabbameini. Læknar sem skrifa út þessi lyf þurfa að vera
meðvitaðir um þessa tengingu. Metformín var tengt við lægri áhættu á
grunnfrumukrabbameini en ekki flöguþekjukrabbameini, en þörf er á frekari
rannsóknum til þess að staðfesta þessa tengingu.An epidemic of basal cell carcinoma (BCC) and squamous cell carcinoma
(SCC) has led to a significant healthcare burden in white populations. The
incidence of both cancers is on the rise, the reasons for which are unclear.
While the principal risk factors for these cancers are fair skin and ultraviolet
radiation (UVR) exposure, certain medications have also been implicated in
increased skin cancer risk through immunosuppression, immunomodulation,
or UVR sensitization. Whole population studies assessing the epidemiology of
and risk factors for BCC and SCC are lacking, and it is unclear whether
medications significantly increase the risk of BCC and SCC development in
the low UV radiation environment that Iceland provides. The primary objective
of this study was to establish incidence rates and tumor burden in an
unselected, geographically isolated population that is exposed to low levels of
UVR. The secondary objective was to delineate the relationship between
SCC/BCC and hydrochlorothiazide (HCTZ), TNF-alpha inhibitors (TNFi), and
statins. These medications have, in some studies, been associated with
increased risk of BCC and SCC development through UV sensitization,
immunosuppression, and immunomodulation, respectively. Lastly, the
relationship between metformin, which has been shown in some studies to
decrease cancer risk, and BCC and SCC development was investigated.
To accomplish our goals, we undertook a whole-population study
based on the Icelandic cancer registry. We assessed incidence according to
age, residence, and multiplicity and assessed trends using joinpoint analysis.
Age-standardized (World) and age-specific incidence rates were calculated
along with cumulative and lifetime risks. To assess the relationship between
medication and skin cancer, we used a population-based case-control study
design. The group of cases consisted of all individuals diagnosed for the first
time with SCCis, invasive SCC, and BCC of the skin. For each case, ten
unaffected population controls, matched by year of birth and sex, were
randomly selected from the National Register of Iceland. We employed
conditional logistic regression analysis to calculate multivariate odds ratios
(ORs).
During the study period, the incidence for all subtypes of KC increased,
despite Iceland’s low background UVR. This increase was most prominent in
women on sites not generally exposed to UV radiation in Iceland: the trunk and legs. Joinpoint analysis showed the fastest increase in SCCis incidence to be
in women. Women with SCCis also had a higher likelihood of developing new
lesions than men, with a multiplicity of 1.71. Men are more likely than women
to develop invasive SCCs, which occur almost exclusively in the head and
neck. Lip SCCs were much more likely to be invasive than in situ. HCTZ was
associated with all subtypes of KC. TNFis and statins were associated with
SCC but not BCC.
Cutaneous KC is becoming a significant public health problem
worldwide. Iceland is the only reported population, to our knowledge, in which
the incidence of BCC and SCCis is significantly higher in women than in men.
While in most countries, men have a higher incidence of BCC and SCC,
Iceland's low UV radiation environment might protect men, as women may be
more likely to engage in high-risk tanning behaviors. Despite the low
background UV radiation in Iceland, high cumulative exposure to the UV
sensitizing medication HCTZ was associated with the development of BCC,
SCCis, and invasive SCC, suggesting that sun-protective behaviors alone may
not eliminate the carcinogenic potential of HCTZ in high UV countries. TNFis
and statins increased individual risk for SCC, but not BCC, a phenomenon also
seen in organ transplant recipients and patients on immunosuppressive
medications such as cyclosporine. These associations require further study.
Public health efforts (focusing on the potentially harmful effects of UVR) and
physician education will be essential to counteract the increasing skin cancer
incidence in Iceland as its population ages. Since metformin use was
associated with decreased BCC development, it is possible that metformin
might be a reasonable option for patients at high risk for developing BCC, or
used to slow the rate of BCC development in patients with multiple skin
cancers. This requires further study using prospective design models.Peer Reviewe
Weathering of volcanic tephra and its impact on soil formation south of Vatnajökull glacier
Get PDFFrequent tephra deposition and a steady influx of aeolian material of diverse origin dominate soil formation in Iceland. Little is known about the weathering behaviour, mineral formation and alteration of tephra and Icelandic soils after tephra deposition. This thesis presents the results from extensive studies on soil mineralogy and pedogenesis in various Icelandic soil types and different soil environments.
The sampling sites were selected according to the presence of the light coloured rhyolitic tephra from the Öræfajökull eruption in 1362 CE and a dark-coloured basaltic Veiðivötn tephra from 1477 CE in the volcanically active area south of Vatnajökull, SE Iceland.
All investigated soils were acidic and dominated by sand. Indicated by Feo/Fed ratios above 0.75, they classify as being in an early stage of chemical weathering and soil development. The major portion of the clay size particles are mainly derived from amorphous and poorly crystalline constituents (allophane and ferrihydrite). However, traces of layer silicates (smectite, hydroxy interlayerd minerals and secondary chlorite) were found at all sites. The determining factor of pedogenesis in the histosols was the OM, but the aeolian transport of tephra over long distances and re-deposition as well as local site conditions, rather than the primary composition of the parent material, were the important factors in the development of all investigated soils and the alteration of minerals. Icelandic soils develop in a very dynamic environment. None of the profiles represented a well-developed-pedon, but appeared disturbed over time, showing signs of external influences.Tíð eldgos með tilheyrandi gjóskufalli og stöðugt áfok vindborinna efna af ólíkum uppruna setja mestan svip á jarðvegsþróun á Íslandi. Skortur er á þekkingu á veðrun, myndun og ummyndun steinda í gjósku í íslenskum jarðvegi í kjölfar gjóskjufalls. Í þessari ritgerð eru niðurstöður umfangsmikillar rannsóknar kynntar, sem tekur til steindafræði og jarðvegsþróunar í mismunandi jarðvegsflokkum og í breytilegu umhverfi jarðvegsmyndunar.
Rannsóknarsvæðið er á virku eldfjallasvæði sunnan við Vatnajökul á Suðausturlandi Á öllum sýnatökustöðum sem notaðir voru í rannsókninni finnast ljóslituð, súr gjóska frá Öræfajökulsgosi frá 1362 e.Kr. og dökklituð, basísk gjóska úr gosi í Veiðivötum árið 1477 e.Kr.
Öll jarðvegsýni í þessari rannsókn reyndust súr og sandkennd. Hlutfall Feo/Fed > 0.75 gefur til kynna að efnaveðrun og jarðvegsþróun sé skammt á veg komin. Meginhluti agna í leirstærð felst í myndlausum (e. amorphous) eða ófullkomlega kristölluðum (e. poorly crystalline) efnum (allófan og ferrihýdrít). Engu að síður fundust ummerki um lagsiliköt á öllum sýnatökustöðum (smektít, steindir með hýdroxýl jónir milli laganna og síð-steindina klórít). Lífræn efni voru ráðandi þáttur jarðvegsþróunar í mójörð (e. histosol), en flutningur gjósku með vindi yfir langar vegalengdir, tilflutningur gjósku og staðbundnir umhverfisþættir réðu meiru um jarðvegsþróun og ummyndun steinda en frumsamsetning móðurefnisins. Íslenskur jarðvegur þróast í síbreytilegu umhverfi. Ekkert jarðvegssniðanna mátti skilgreina sem vel þróað og öll sýndu þau ummerki um rask og áhrif frá ytri umhverfisþáttum
The feasibility of integrating insights from character education and sustainability education – a Delphi study
Get PDFAlthough fostering values is promoted within sustainability education (SE), many educators appear concerned or conflicted about how, or whether, to approach values education. An interdisciplinary research project sought to draw on insights from character education (CE) in order to explore the problem. Using the Delphi technique, 12 CE and SE experts were gathered, via email, to explore their perceptions regarding the feasibility of integrating theoretical/practical insights from the CE and SE fields. Experts rated their agreement and made comments on 41 statements. Fourteen statements reached ‘consensus’. Thematic analysis revealed experts’ agreement on an ethical base of SE providing practical application of CE; a perceived tension between democracy, pluralism and normativity; reservations about the individual nature of CE; the need for CE, and SE, to more actively foster awareness of self as part of nature; a desire for holistic and interdisciplinary education; concern regarding exam-driven education and agreement on the need to re-examine the purpose of education. The findings reveal common ground between the two fields, as well as indicating where differences could be bridged and misunderstandings addressed, suggesting avenues for future collaboration and potential integration – possibilities that it would be fruitful to pursue through further interdisciplinary research.This work was supported by the Icelandic Centre for Research [141,878-051].Accepted Manuscript (Peer Reviewed
Polish Borrowings in Wymysorys. A Formal Linguistic Analysis of Germano-Slavonic Language Contact in Wilamowice
Get PDFThe present dissertation concerns formal aspects of Polish borrowing in 21st-century Wymysorys – a minority Germanic language spoken by a few dozen people in the town of Wilamowice in Poland. By drawing on modern borrowing theories and his own empirical studies conducted in situ, the author documents, describes, and explains all cases and types of Polish borrowings that may currently be found across the Wymysorys sound system, lexicon, and grammar. The evidence demonstrates that Polish has influenced Wymysorys to a significant extent, both quantitatively and qualitatively. The quantitative impact surfaces in the high type frequency of linguistic elements that have been borrowed. The qualitative impact transpires in the wide range and diversity of the parts of the language being affected, whether in the sound system (Polish has affected phonetics, phonology, phonotactics, and prosody, in addition to consonants and vowels), lexicon (Polish has affected nearly all lexical classes, both content and functional, and most of their sub-types), and grammar (Polish has affected derivational and inflectional morphology, morpho-syntax, and syntax). The extent of the Polish influence is such that the original typological profile of Wymysorys and its Germanic essence could be viewed as compromised: the Wymysorys language shifts towards a blended Germanic-Slavonic profile.Þessi ritgerð fjallar um formlega lántöku úr pólsku í nútíma vymysorysku – germönsku
minnihlutatungumáli sem talað er af nokkrum tugum manna í bænum Wilamowice í Póllandi.
Verkið, sem byggir á nútímalegum kenningum um lántöku og rannsóknum sem gerðar voru á
staðnum, skjalfestir, lýsir og útskýrir öll tilvik og gerðir pólskrar lántöku sem er að finna í
málfræði og orðasafni vymysorysku 21. aldar. Gögnin sýna að pólska hefur haft mikil áhrif á
vymysorysku, bæði megindlega og eigindlega. Megindleg áhrif koma fram í hárri tíðni
tungumálaþátta sem hafa verið fengnir að láni. Eigindleg áhrif sjást á fjölbreytileika þeirra hluta
tungumálsins sem hafa orðið fyrir áhrifum, hvort sem það er hljóðkerfi (pólska hefur haft áhrif á
hljóð (bæði samhljóð og sérhljóð), hljóðkerfi, hljóðskipun og hljómfall), orðmyndunar- or
beygingarkerfi (pólska hefur haft áhrif á formgerð orða, bæði afleiðslu og beygingar), orðskipun
(pólska hefur haft áhrif á setningagerð) eða orðasafn (pólska hefur haft áhrif á næstum alla
orðflokka og flestar tegundir þeirra). Umfang pólskra áhrifa eru slík, að telja verður að
upprunaleg gerð vymysorysku og germanskur kjarni hennar eigi á hættu að hverfa, þar sem
tungumálið færist í átt að blönduðu germansk-slavnesku sniði
Using scanning Doppler lidar to enhance aviation safety in Iceland
Get PDFLidar systems have been used widely to measure wind profiles and atmospheric aerosols. The scanning Doppler lidars operated by the Icelandic Meteorological Office can provide continuous measurements of the wind velocity and direction based on the Doppler effect, from the emitted signal, as well as the backscatter coefficient and depolarization ratio for retrieving aerosol properties. In this project, we investigate the use of Doppler lidars in Iceland, especially for enhancing aviation safety. The project was divided into three main tasks have been conducted: 1) atmospheric turbulence measurements; 2) airborne aerosol detection; 3) real-time lidar signal classification with machine learning algorithms. In the first task, an algorithm was developed based on the Kolmogorov theory to retrieve eddy dissipation rate, as an indicator of turbulence intensity, from lidar wind measurements. The method was tested on two cases from 2017. In the second task, the Doppler lidar was used in combination with ceilometers, a sun-photometer and other instruments, to detect aerosols, including dust and volcanic ash in Iceland. In the third task, both supervised and unsupervised machine learning algorithms were developed to identify the noise signal and classify the lidar measurements, with the aim of providing real-time lidar signal classification for potential end-users. The results indicate that the Doppler lidar can significantly improve aviation safety and complement meteorological measurements by detecting atmospheric turbulence or volcanic ash clouds in Iceland.Vind- og agnasjár (e. lidar) hafa verið notaðar víða til að mæla vindsnið og nema svifryk og aðrar agnir í lofthjúpnum. Veðurstofa Ísland á tvo Doppler agnasjár sem geta veitt samfelldar mælingar á vindhraða og -stefnu, byggðar á Dopplerhrifa, og endurkastsstuðul og tvípólunarhlutfall (e. depolarization ratio) agna. Í þessu verkefni var könnuð notkun Doppler agnasjár á Íslandi til að auka flugöryggi. Verkefninu var skipt niður í þrjá verkþætti: i) ókyrrðarmælingar í jaðarlaginui; ii) svifryk og aðrar agnir í lofthjúpnum; iii) rauntímaflokkun agna með vélrænu námi (e. machine learning). Í verkþætti i) var þróuð reikniaðferð byggð á kenningu Kolmogorov til að meta sveipeyðingarákefð (e. eddy dissipation rate) frá vindmælingum, sem vísbendingu um ókyrrðarstyrk Aðferðin var prófuð í tveimur tilvikum frá árið 2017. Í verkþætti ii) voru gögn frá Doppler agnasjánni notuð, með gögnum úr skýjahæðamæli, sólarljósamæli og öðrum tækjum til að greina svifryk, þar með talið ryk og eldfjallaösku á Íslandi. Í verkþættii iii) var þróaðvélrænt nám, bæði undir eftirliti og án eftirlits, til að bera kennsl á suð og flokka mælingarnar með það að markmiði að veita rauntímaliðaflokkun fyrir hugsanlega notendur. Niðurstöðurnar benda til þess að Doppler vind- og agnasjá geti bætt verulega flugöryggi og verið góð viðbót við hefðbundnari veðurmælingar á Íslandi, með því að greina ókyrrð og öskuí lofti.ISAVI