43 research outputs found
Quantification of antiadhesion effect of combined natural compounds on bacteria Campylobacter jejuni and Listeria monocytogenes with PCR based methods
No full textNaraščanje odpornosti patogenih bakterij na antibiotike ter odpornost biofilmskih oblik bakterij, ki so prisotne na abiotskih površinah v živilski industriji, predstavlja velik izziv pri zagotavljanju varne hrane. Trenutne raziskave so usmerjene v iskanje alternativnih učinkovin naravnega izvora in v mehanizem njihovega delovanja na bakterijske celice. Obenem je potreben razvoj hitrih, specifičnih in cenovno dostopnih metod za detekcijo in kvantifikacijo patogenih bakterij v živilskih proizvodnih obratih. V delu smo se osredotočili na adhezijsko sposobnost Gram negativnih bakterij C. jejuni in Gram pozitivnih bakterij L. monocytogenes ter optimizirali metodo za kvantifikacijo adheriranih bakterij. Z uporabo metode digitalnega PCR (dPCR) smo pripravili umeritveno krivuljo ter nadalje z uporabo metode PCR v realnem času (qPCR) določili število pomnožkov tarčne DNK, ki predstavlja premosorazmerno količino adheriranih bakterij na polistiren. Nato smo preverili protiadhezijsko učinkovitost naravnih učinkovin karvakrola, timola, α-pinena in epigalokatehin galata (EGKG) v subinhibitorni koncentraciji (0,1 mg/ ml). Posamezen dodatek karvakrola, timola in EGKG je inhibiral adhezijo za več kot 90 %. Več kot 99 % inhibicijo adhezije smo ugotovili pri kombiniranju karvakrola, timola in EGKG ter pri kombiniranju vseh štirih učinkovin. Naravne učinkovine predstavljajo alternativno strategijo pri preprečevanju adhezije bakterij ter posledično nastanka biofilma na abiotskih površinah.Increased antibiotic resistance of pathogenic bacteria and the resistance of bacterial biofilms on the abiotic surfaces in the food industry is a major challenge for ensuring food safety. Current research is focused on alternative components of natural origin as well as on the mechanisms of their action on bacterial cells. At the same time, there is an urgent need for development of fast, specific and cost-effective methods for detection and quantification of pathogenic bacteria in production facilities. In our research, we focused on adhesion of Gram negative C. jejuni and Gram positive L. monocytogenes bacteria. By combining digital PCR and real time PCR methods, we were able to quantify DNA amplicons, which are proportional to the quantity of cells that adhered on polystyrene surface. Furthermore, we evaluated the anti-adhesive effect of natural compounds, such as carvacrol, thymol, α-pinene and epigallocatechin gallate (EGCG). The addition of carvacrol, thymol and EGCG individually in subinhibitory concentration showed more than 90% reduction of adhesion. Moreover, more than 99% adhesion inhibiton was shown when combining the above three compounds and all four of them. As seen, the natural compounds present an efficient alternative strategy in prevention of bacterial adhesion and consequent biofilm formation
Modelling of ITS measures with microscopic simulation
No full textMagistrsko delo obravnava uporabo mikroskopske simulacije za modeliranje ITS ukrepov. V
začetnem delu naloge je predstavljena tematika, vsebina in aktualnost. V drugem poglavju so
predstavljeni ukrepi ITS, ki so primerni za modeliranje v mikroskopski simulaciji. To so
predvsem ukrepi za povečanje kapacitet na samem cestnem omrežju. Tretje poglavje podaja
osnove mikroskopskega modeliranja s poudarkom na tistih vsebinah, ki so ključne pri ITS
ukrepih. Predstavljeno je tudi ekonomsko vrednotenje na podlagi rezultatov mikroskopske
simulacije. Četrto poglavje je ključni del naloge, to je modeliranje in analiza rezultatov
uvedbe ITS ukrepov. Za posamezne praktične primere so rezultati prikazani vizualno in
analitično, na način, ki hkrati predstavi možnosti, ki jih za to ponujajo orodja za
mikroskopsko simulacijo. V zaključku so povzete koristi, ki jih prinaša uvedba ITS ukrepov
in podani predlogi za še hitrejše uvajanje ITS tehnologije v slovenski prostor.The present master\u27s thesis deals with the use of microscopic simulation to model ITS
measures. The beginning of the thesis presents the theme, its relevance and content. The
second chapter presents the ITS measures that are appropriate for modeling with the
microscopic simulation. These are mainly measures to increase capacity of the road network.
The third chapter presents basics of microscopic modeling with emphasis on those topics that
are relevant for ITS measures. Economic evaluation based on the results of microscopic
simulations is also presented. The fourth chapter is a key part of the task, that is, modeling
and analysis of the results of ITS measure deployment. For all practical examples the results
are shown visually and analytically, in a way that simultaneously presents opportunities to do
so by suitable software for the microscopic simulation. Conclusion summarizes the benefits
from the introduction of ITS measures and proposes even faster deployment of ITS
technologies in Slovenian
NORMATIVE REGULATION OF LEGISLATIVE PROCEDURE IN SLOVENIA
No full textDiplomska naloga obravnava ureditev zakonodajnega postopka v Sloveniji, pri čemer poseben poudarek namenja razčlenitvi in uporabi določil poslovnika državnega zbora. Ker zakonodajni postopek predstavlja nekakšno stičišče politike in prava, je toliko bolj zanimiv za preučevanje in primerjavo teoretično-pravnega vidika na eni, z njegovim uporabno-praktičnim vidikom na drugi strani. Na tej podlagi avtor sprotno izpostavlja predvsem posamezne pomanjkljivosti veljavne ureditve zakonodajnega postopka ter navaja konkretne predloge izboljšav ali vsaj nakaže vsebinske usmeritve zanje, ki bi omogočali njegov učinkovitejši potek.
V začetnem delu naloge so predstavljeni nosilci zakonske iniciative, ki po slovenskem ustavnem redu lahko sprožijo zakonodajni postopek, ter njihove obveznosti pri uresničevanju te pravice. Zaradi izpolnjevanja vse bolj zahtevnih vsebinskih pogojev ob pripravi in vložitvi predloga zakona v zakonodajni postopek, naloga odpira vprašanje upravičenosti tovrstnega omejevanja zakonske iniciative ter usmerja odgovornost za kvalitetno pripravljene predloge zakonov predvsem na vlado. V prikazu poteka rednega zakonodajnega postopka so sprotno izpostavljene razlike med preteklo in sedanjo poslovniško ureditvijo, ki je razumno omejila možnosti za razpravo ter na ta način pospešila postopek. V luči tovrstnega razlikovanja je veljavni poslovnik na novo opredelil vloge in odgovornost udeležencev zakonodajnega postopka, pri čemer je težišče odločanja prenesel na delovna telesa državnega zbora. Avtor pri tem opozarja na nekatere pomanjkljivosti takšne ureditve, ki v praksi omogočajo zlorabo zakonodajnega postopka, ter v izogib temu predlaga razmislek o ustreznih spremembah poslovnika.
V nadaljevanju naloge so podrobneje opredeljeni posebni zakonodajni postopki, ki bi se načeloma morali uporabljati zgolj v izjemnih primerih. Statistični podatki in praktične izkušnje dokazujejo, da temu ni tako, zato je pozornost usmerjena predvsem k iskanju vzrokov za prepogosto uporabo posebnih zakonodajnih postopkov. Doslednejše spoštovanje veljavnih poslovniških določil ali zaostreni pogoji uporabe posebnih postopkov predstavljata alternativni možnosti za rešitev tega vprašanja. Odprto pa ostaja tudi vprašanje morebitnih poslovniških sprememb postopka ponovnega odločanja o zakonu ter posledično večje vloge državnega sveta v zakonodajnem postopku, čemur državni zbor doslej ni prisluhnil. Verjetno bo zato v prihodnje morala politika dokončno odgovoriti na vprašanje, ali državni svet sploh še potrebujemo oziroma kakšna naj bo njegova vloga v zakonodajnem postopku.
Zadnji del naloge je pozornost namenil poslovniškima institutoma, predhodne obravnave in javne predstavitve mnenj, ki lahko prispevata koristen vsebinski doprinos k sprejemanju odločitev v zakonodajnemu postopku. Upoštevaje pretekle izkušnje, bi državni zbor moral uporabi obeh institutov nameniti več časa in pozornosti, saj je, zlasti pri pomembnejših zakonskih predlogih, smotrno preveriti stopnjo sprejemljivosti oziroma podpore posameznim rešitvam.
Še tako kvalitetno pripravljeni predlogi zakonov ter optimalna poslovniška ureditev zakonodajnega postopka pa sama po sebi ne pripomoreta k njegovi večji učinkovitosti. Po avtorjevem prepričanju je za dosego tega cilja nujna tudi primerna organizacija dela v državnem zboru, zlasti pa politična volja in kultura vseh udeležencev zakonodajnega postopka.The thesis addresses the set-up of the legislative procedure in Slovenia, laying special emphasis on the subdivision and application of the provisions in the Rules of Procedure of the National Assembly. As the legislative procedure represents a kind of juncture between politics and law it is hence an even more interesting subject for examination and comparison between the theoretical legal aspect on the one hand and the aspect of practical application on the other. It is based on this that the author throughout the progress of the examination sets out particularly the individual deficiencies of the set-up of the legislative procedure in force while presenting concrete proposals for improvements or at the very least indicating substantive orientations thereof that would contribute to a more efficient operation of the legislative procedure.
The first part of the thesis presents the holders of legislative initiative, who according to the constitutional order of Slovenia are granted the right to initiate the legislative procedure, and their obligations concerning the implementation of this right. Due to the ever growing requirements regarding the substantive conditions that apply to the preparation and submission of an act proposal to the legislative procedure the present thesis raises the question of the legitimacy of such limitations to the legislative initiative and directs the responsibility for the quality of the act proposal preparation mostly onto the government. The outline of the ordinary legislative procedure course is accompanied by setting out the differences between the previous arrangements pertaining to the Rules of Procedure and the ones currently in force, the latter having reasonably limited the possibilities for debate and thereby accelerated the procedure itself. In the light of such modification, the Rules of Procedure in force have identified the roles and responsibilities of the participants in the legislative procedure anew, whereby the backbone of decision making has been carried over to the working bodies of the National Assembly. Regarding this, the author points out certain deficiencies of such a set-up, as it may in practice allow abuse of the legislative procedure, and suggests considering appropriate changes to the Rules of Procedure to avoid such abuse.
In continuation, the thesis presents a detailed definition of special legislative procedures which should in principle apply only in exceptional cases. Statistical data and past experience, however, show that this is not the case, therefore the focus is laid particularly on exploring the reasons for a too frequent application of special legislative procedures. A more consistent compliance with the provisions of the Rules of Procedure in force or stricter conditions on the application of special legislative procedures represent alternatives to solve the issue in question. What also remains open is the issue of possible changes to the Rules of Procedure regarding act proposals returned to the legislative procedure and consequently the issue of a greater role of the National Council in the legislative procedure, which insofar the National Assembly has not taken into consideration. Politics will therefore in the future probably have to address the question of whether there is still even a need for the National Council or what kind of role it should take on in the legislative procedure.
The final part of the thesis focuses on the two institutes of the Rules of Procedure, namely the preliminary reading and public presentation of opinions, which can substantively and beneficially contribute to the decision making in the legislative procedure. Based on the past experience, the National Assembly should dedicate more time and attention to the application of both the institutes mentioned, as it is wise, particularly with act proposals of greater importance, to examine the level of acceptance or support to individual solutions.
Even a high quality of act proposal preparation and an optimal set-up of the Rules of Procedure are, however, not pe
Design and Implementation of the Andromeda Proof Assistant
No full textAndromeda is an LCF-style proof assistant where the user builds derivable judgments by writing code in a meta-level programming language AML. The only trusted component of Andromeda is a minimalist nucleus (an implementation of the inference rules of an object-level type theory), which controls construction and decomposition of type-theoretic judgments.
Since the nucleus does not perform complex tasks like equality checking beyond syntactic equality, this responsibility is delegated to the user, who implements one or more equality checking procedures in the meta-language. The AML interpreter requests witnesses of equality from user code using the mechanism of algebraic operations and handlers. Dynamic checks in the nucleus guarantee that no invalid object-level derivations can be constructed.
To demonstrate the flexibility of this system structure, we implemented a nucleus consisting of dependent type theory with equality reflection. Equality reflection provides a very high level of expressiveness, as it allows the user to add new judgmental equalities, but it also destroys desirable meta-theoretic properties of type theory (such as decidability and strong normalization).
The power of effects and handlers in AML is demonstrated by a standard library that provides default algorithms for equality checking, computation of normal forms, and implicit argument filling. Users can extend these new algorithms by providing local "hints" or by completely replacing these algorithms for particular developments. We demonstrate the resulting system by showing how to axiomatize and compute with natural numbers, by axiomatizing the untyped lambda-calculus, and by implementing a simple automated system for managing a universe of types
Su Shi in razcvet tem v poeziji ci – na primeru pesmi na melodijo »Mesečina na Zahodni reki«
No full textThe study explains characteristics of ci 詞 poetry and uses fifteen of Su Shi’s 蘇軾 (1037–1101) ci poems written to the tune “Moonlight over the West River”, translated by the author of this study, to investigate Su Shi’s treatment of ci poetry as shi 詞 poetry (以詩為 詞), as well as the themes of these poems. The examples show that in both his traditional and innovative poems Su Shi expands the themes with allusions, relying on borrowings from literary, historic, and philosophical works, and making associations with stories, events, and people from history, mythology, and literature.Študija razloži značilnosti poezije ci 詞 in na primeru enega najpomembnejših pesnikov oblike ci iz dinastije Song (960–1279), Su Shija 蘇軾 (1037–1101), in njegovih petnajst pesmi, ki jih je napesnil na melodijo ・・Mesečina na Zahodni reki・・, razišče njegovo inovativnost pri širjenju tematike v obliki ci s pristopom našanja elementov poezije shi 詩 v poezijo ci (以詩為詞). Teh petnajst Su Shijevih pesmi, ki jih je iz kitajščine prepesnila avtorica študije, kaže tematsko pestrost, ki je poezija ci pred Su Shijem ni poznala. Tako v tradicionalnih kot inovativnih pesmih Su Shi širi tematiko s pomočjo aluzij, sposojanjem elementov iz literarnih, zgodovinskih, filozofskih del in z ustvarjanjem asociacij na zgodbe, dogodke in osebe iz zgodovine, mitologije in literature.
An Introduction to Algebraic Effects and Handlers. Invited tutorial paper
No full textAbstractThis paper is a tutorial on algebraic effects and handlers. In it, we explain what algebraic effects are, give ample examples to explain how handlers work, define an operational semantics and a type & effect system, show how one can reason about effects, and give pointers for further reading
Intravenous Thrombolysis After Dabigatran Reversal by Idarucizumab: A Systematic Review of the Literature
No full textBackground and Purpose: Idarucizumab achieves instant reversal of anticoagulation and enables intravenous thrombolysis (IVT) in dabigatran-treated acute ischemic stroke (AIS) patients. AIS in dabigatran-treated patients is a rare event, therefore the experience is limited. A review of all published cases was performed to evaluate the safety and effectiveness of this therapeutic strategy. Methods: We searched PubMed and Scopus for all published cases of IVT after reversal with idarucizumab in dabigatran-treated AIS patients. The outcomes were safety assessed by hemorhagic transformation (HT), symptomatic intracranial hemorrhage (SICH) and death, and efficacy assessed by National Institutes of Health Stroke Scale (NIHSS) reduction. Results: We identified 251 AIS patients (39,9% females) with an average age of 74 years. HT, SICH, and death were reported in 19 (7.6%), 9 (3.6%), and 21 (8.4%) patients, respectively. Patients experiencing HT presented with more severe strokes (median NIHSS on admission: 21 vs. 8, p < 0.001; OR: 1.12, 95% CI: 1.05-1.20). After IVT there was a significant NIHSS reduction of 6 points (IQR:3-10, p < 0.001) post-stroke and linear regression revealed a correlation of admission NIHSS to NIHSS reduction (p < 0.001). Conclusions: In this systematic review of all published cases of IVT in dabigatran-treated AIS patients after reversal with idarucizumab the rates of HT, SICH and mortality, as well as NIHSS reduction, were comparable with previous studies in non-anticoagulated patients. This provides reassuring evidence about the safety and efficacy of this therapeutic strategy. © Copyright © 2021 Frol, Sagris, Pretnar Oblak, Šabovič and Ntaios
The Individual Anomalies and Aggregate Impacts of Households’ Consumption and Savings Decisions
No full textAn economy, at its core, consists of people doing things. People work and play, eat and drink, create and think, and all the while perform activities both measured and unmeasured that nonetheless provide value to themselves, their families, and society at large. Within this structure, the most fundamental unit of our modern economy is the household, which consists of at least one consumer who spends time consuming some positive amount of net resources. This consumer may also spend time supplying labor or investing in new ideas or various speculative enterprises so that he can afford his desired consumption level. Even if he does not work or invest, he still must consume in order to ensure his sustenance and continued living. Thus, while the consumer comprises the core unit of the modern economy, it is consumption itself which is the economy’s most central activity. In the United States, consumption amounts to almost 70% of all output. To better understand the many important factors that drive broadaggregate economic outcomes, it behooves us to study the behavior of individual consumers themselves. A goal of mine as a researcher is to continue working to expand the frontier of knowledge pertaining to the motivations and outcomes of household behaviors. And while this thesis does not reflect all of my economic research projects currently underway, it does fully reflect the variegated flavors of the questions and puzzles I consider. Here, I focus on two particular frontiers in household economic research. In Chapters 1 and 2, along with co-authors, I consider how the allocation of off-market time directly affects consumption, savings, the labor supply,and aggregate growth. In Chapters 3 and 4, along with co-authors, I apply theories from behavioral economics, like mental accounting and the non-fungibility of various forms ofliquidity, to explore the high-frequency spending and savings patterns of individual consumers. While the first two chapters consider how mechanisms behind household decisions drive macroeconomic outcomes, the latter chapters deal with granular, microeconomic behavior. Thisthesis thus represents the breadth of my many research interests spanning both macro- and microeconomics.Since Becker (1965), economists focussing on household decisions have grappled with the classic consumption/leisure tradeoff in various applications. However, rich decision structures, like Becker’s original theoretical model featuring multiple off-market time utilization decisions, have been only minimally explored. Data limitations may be to blame: in the United Statesquality time use data has only been available since 2003, while other developed countries lack a comprehensive time use survey of households. Still though, we can gain further insight into many well-established economic puzzles, like the reason for the rise in the U.S. services share I explore in Chapter 1, or the decline in long-run U.S. GDP growth I explore in Chapter 2, among others, by examining these phenomena in model environments where households face rich, previously unexplored time use decisions.Chapter 1 features joint work with co-author William Bednar. We consider an application of a home production model toward United States structural change where households decidehow much time to spend consuming various market purchases. In the context of our problem, structural change is the process by which the share of consumption devoted toward intangible services has risen while the share of consumption devoted toward physical, manufacturedgoods has fallen. There is contentious debate in the literature as to whether supply-side factors or demand-side factors have driven the rise in the services share of aggregate output. Income effects from non-homothetic consumer preferences have been touted as a primary contributor. We test this implication in a model that accounts for consumers’ joint consumption and offmarket time allocation decisions. When accounting for time to consume in this manner, we show that homothetic utility functions can still generate non-linear expansion paths as wagesincrease. In the model, differences in the time intensities of different home production activities affect how consumers adjust their consumption allocation in response to relative price and real wage changes. Our findings suggest that the rise in the U.S. services share since 1948 is primarily due to relative price changes which dominate income effects from wage growth, contrasting with many findings in the literature.In Chapter 2, I work with co-author Finn Kydland to address how population aging will impact aggregate GDP growth when accounting for the time working-age adults spend caring for their elders. As the population of the United States ages, the number of elderly people who require living assistance is increasing. To understand how this impacts aggregate output, we calibrate an overlapping generations model where growth endogenously depends on thecare young agents choose to provide for their parents. Relative to an economy with a constant population distribution, we project that population aging will reduce GDP 17% by 2056 and 39% by 2096. Curing old-age diseases such as Alzheimer’s and dementia can lead to 5.4% higher output relative to the baseline, while improving welfare for consumers of all ages. The mental accounting theories of Richard Thaler have inspired a generation of behavioral scientists to reconsider how consumer behavior departs from predictions of classic economic models of rationality. Until recently, Thaler’s theories have been largely isolated to applications in experimental and other controlled settings. Further, there lacks broad consensus as to whattypes of behavior exactly correspond to mental accounting. In Chapters 3 and 4, along with co-authors Alan Montgomery and Christopher Y. Olivola, I apply Thaler’s various theories of mental accounting to transaction-level field data from consumers’ bank balance ledgers.Generally, we seek to understand the degree to which mental accounting behavior is actually observed in consumption spending data and also the degree to which including flexible, behavioral features like mental accounting can improve the fit and predictions of structural models ofdemand. In Chapter 3 we construct a unifying theory of two stage budgeting and mental accounting in order to reconcile heterogeneity in consumer-level weekly spending and savings patterns. Mental accounting and rational inattention induce behavioral wedges between first stage expenditure budgets and second stage actual expenditure. Specifically, consumers engage in Gabaix (2014) sparse maximization, re-assessing only a subset of their spending budgets everyperiod. Over or under spending affects future budgeting and expenditure decisions. With agent-level weekly expenditure data, we use latent Bayesian inference to structurally estimate the degree to which low-income consumers appear constrained by mental accounting frictions. We find that consumers optimally set only 25-50% of first stage budgets each period. A sparse max model with mental accounting fits the data best, compared to alternative models withoutone and/or the other. In a counterfactual experiment, relaxing rationality constraints leading to greater budget attentiveness is not necessarily welfare improving if consumers can easily adjust budgets on the fly to mitigate the disutility of over expenditure. We are the first toestimate the structural parameters and latent decisions of a two stage budgeting model with sparse maximization and mental accounting. In doing so, demand shifters in our estimation are endogenous, resulting from behavioral frictions. In the final chapter I engage in a second application of mental accounting theory to exploreempirical evidence that consumers use liquidity from debit cards and credit cards differently. Thaler (1999) describes one of the primary components of mental accounting as the budgeting of specific utility-providing activities which can depend on the resources used to fund those activities. The analysis presented in this chapter focusses on household expenditure of durable and non-durable goods and the liquidity sources used to fund these different expenditures.Specifically, we exploit a linked dataset of credit and debit card users to examine consumer purchasing patterns of durable and non-durable consumption commodities under both methods of payment. Our findings suggest that on average durable purchases are more sensitiveto increases in available credit than non-durable purchases, and most consumers are more likely to increase total consumption due to increases in available credit than increases in available checking account balances. We empirically show that the standard neo-classicalconsumption/savings model, the equilibrium conditions of which implicitly assume that the household’s available resources (liquidity and investments) are perfectly fungible, fails to rationalize our data for the median/modal consumer in our sample. However, our results are rich because we also show that the behavioral distribution of consumers includes both households which treat liquidity as fungible and those that do not. Given the heterogeneity we find, future work should test whether these results would matter on aggregate.</div
