31 research outputs found
A comparison of unitary and collective household models to estimate labour supply in Austria
Die vorliegende Arbeit betrachtet verschiedene Arbeitsangebotsmodelle und evaluiert deren SchĂ€tzgĂŒte im theoretischen aber auch angewandten Sinne (basierend auf den EU-SILC Daten 2004-2006 der Statistik Austria).
Die zwei Modelle die untersucht werden, sind unitÀre Haushaltsmodelle, welche den Haushalt als einen einzelnen Entscheidungstreffer ansehen, und kollektive Modelle, welche die Individuen als solche erkennen und zu einem Haushalt kombinieren.
Zuerst werden die theoretischen Grundlagen erlĂ€utert. Annahmen und LiteraturĂŒberblicke werden besprochen. Dem folgend wird das statische Arbeitsangebotsmodel, das beiden Modellen zu Grunde liegt, erklĂ€rt. Dabei handelt es sich um ein Nutzenmaximierungsproblem, welches auf Budgetrestriktionen und Nutzenfunktionen basiert. Weitere Modellannahmen und Eigenschaften der empirischen SchĂ€tzung werden erlĂ€utert, unter anderem die verwendete Conditional Logit SchĂ€tzmethode.
Vor dem empirischen Teil der Arbeit, werden die Daten begutachtet. Diese von der Statistik Austria stammenden Daten, wurden von einer europaweiten Datenerhebung namens European Union Statistics on Income and Living Conditions fĂŒr die Jahre 2004-2006 bezogen. Die relevantesten Variablen werden erklĂ€rt und manche Statistiken liefern bereits aufschlussreiche Resultate. Unter anderem lĂ€sst sich erkennen, dass MĂ€nner unabhĂ€ngig von der familiĂ€ren Situation gröĂtenteils Vollzeit arbeiten. Im Gegensatz dazu treffen Frauen mit verschiedenen Haushaltssituationen unterschiedliche Arbeitsangebotsentscheidungen. Eine der wichtigsten erklĂ€renden Variablen fĂŒr die Arbeitsstundenwahl ist das Nettoeinkommen. Um dieses vom Bruttoeinkommen zu errechnen wurde von dem Team um Dr.Zulehner am WIFO ein Steuer- Transferrechner fĂŒr Ăsterreich entwickeltwelcher es ermöglicht, vom Brutto auf das Nettoeinkommen zu schlissen.
Die SchÀtzung des Nutzens basiert auf zwei verschiedenen Funktionen, der translogen und der quadratischen Nutzenfunktion.
Das unitÀre Modell schÀtzt diese auf der Basis von Haushaltsvariablen.
Das kollektive Model ist etwas aufwendiger zu schÀtzen. Man braucht eine Teilungsregel welche aussagt, welchen Teil des Gesamteinkommens die Frau und welchen der Mann bekommt. Diese Aufteilung wird geschÀtzt anhand von Variablen so wie Einkommenspotenzial oder Lohn. Nachdem die individuellen Nutzen geschÀtzt wurden, werden diese zu einem Haushaltsnutzen kombiniert. Dies geschieht durch eine Gewichtung (laut Teilungsregel) der einzelnen Nutzenniveaus.
Ein klarer Nachteil der unitĂ€ren Modelle ist, dass individuelle PrĂ€ferenzen keine Relevanz haben und daher können Reaktionen der einzelnen Haushaltsmitglieder nicht analysiert werden. Das kollektive Model erlaubt individuelle PrĂ€ferenzen und ermöglicht damit Analysieren von PolitikmaĂnahmen, welche ein Haushaltsmitglied mehr als ein anderes trifft. Basierend auf dieser Grundlage wĂŒrde man das kollektive Model bevorzugen. Jedoch erweist sich dieses in der empirischen SchĂ€tzung als problematischer. Zwei Methoden wurden angewandt. Die erste, welche Zwischenresultate verwendet, um eine KonsumschĂ€tzung zu erzielen, fĂŒhrt zu keinem Resultat. Der zweite Zugang, eine Kalibrierungsmethode, resultiert, wenn man dem Ansatz der Literatur folgt, im keinem interpretierbaren Ergebnis. Es erlaubt uns jedoch eine alternative Errechnung des kombinierten Haushaltsnutzens zu erzielen, indem man nicht bloĂ die Nutzenniveaus gewichtet und addiert, sondern einen Interaktionsterm einbaut, welcher den Unterschied der Nutzen der Partner adressiert. Dieser zusĂ€tzliche Term erlaubt es einen besseren Fit zu erzielen.
Das unitĂ€re Model basiert auf der Annahme, dass die Herkunft des Einkommens unentscheidend ist und nur das summierte Haushaltseinkommen die Konsum- und Arbeitsangebotsentscheidung beeinflusst (Income Pooling Hypothese). Diese Hypothese findet jedoch keine empirische BestĂ€tigung. Dieses Ergebnis lĂ€sst uns an den folgenden Resultaten zweifeln. Wir prĂ€sentieren sie jedoch, da sie vielleicht Grundtendenzen erkennen lassen. Das Ergebnis deutet darauf hin, dass der Nutzen wie erwartet (in beiden Modellen) mit Konsum und Freizeit positiv assoziiert werden kann. Frauen scheinen Freizeit mehr zu schĂ€tzen, wenn mehrere jĂŒngere Kinder im Haushalt leben. Beide Partner haben eine höhere PrĂ€ferenz fĂŒr Freizeit mit steigendem Alter.
Vergleicht man die zwei Modelle fĂŒr die EU-SILC Daten kann man festhalten, dass das unitĂ€re Model einfacher zu schĂ€tzen ist. Daher ist es ratsam mit dieser SchĂ€tzung zu beginnen und auch deren Income Pooling Hypothese zu testen. Muss Letztere verworfen werden, deutet dies auf individuelle PrĂ€ferenzen hin und man sollte ein kollektives Model schĂ€tzen. Diese zeichneten sich in dieser Arbeit durch ihre komplexe empirische Analyse aus. Falls man als ĂkonomIn jedoch an personenspezifischen ArbeitsangebotsverĂ€nderungen interessiert sein sollte, sind diese HĂŒrden wert ĂŒberwunden zu werden.The purpose of this paper is to compare two approaches of estimating and modeling the labour supply of a household. Hereby the central question will be if a household can be seen as one decision making unit or if it should be perceived as two individuals (most often wife and husband) each with her/his own preferences. The unitary model captures the first perception while the collective model represents the two individuals household concept. Later requires more individual data and a sharing rule needs to be calculated as one extra step. The two models will be explained and compared at a theoretical and an econometric level.
In order to see the models applied to real data the EU-SILC data set for Austria provided by Statistik Austria is used. Even though the data set is not perfect for the collective model, it allows us to see advantages and disadvantages that both models might have in empirical studies.
This paper uses a discrete hours approach that allows for four working hours categories and only considers multi-person households. The theoretical base for all models is the static labour supply model and the estimation technique used will be the conditional logit one. As these help to understand the estimation procedure, they will find some attention in this work. Furthermore the data will be described which allows us to immediately draw some interesting conclusions. Another central piece of this work is the transfer-benefit calculator that translates gross into net incomes.
The empirical results reject the income-pooling hypothesis that is the main assumption of the unitary model. It further suggests that women appreciate leisure more the more young children they have. Both partners enjoy leisure more with age.
The collective model estimation turns out to be quite cumbersome. It leads us to doubt the construction of the household utility and so a utility interaction term is included that punishes utility differences between partners.
Concluding it can be said that the collective model turns out to be less straightforward to estimate for the Austrian data. It however allows drawing conclusions on an individual level, which is a crucial property
An Insect Herbivore Microbiome with High Plant Biomass-Degrading Capacity
Herbivores can gain indirect access to recalcitrant carbon present in plant cell walls through symbiotic associations with lignocellulolytic microbes. A paradigmatic example is the leaf-cutter ant (Tribe: Attini), which uses fresh leaves to cultivate a fungus for food in specialized gardens. Using a combination of sugar composition analyses, metagenomics, and whole-genome sequencing, we reveal that the fungus garden microbiome of leaf-cutter ants is composed of a diverse community of bacteria with high plant biomass-degrading capacity. Comparison of this microbiome's predicted carbohydrate-degrading enzyme profile with other metagenomes shows closest similarity to the bovine rumen, indicating evolutionary convergence of plant biomass degrading potential between two important herbivorous animals. Genomic and physiological characterization of two dominant bacteria in the fungus garden microbiome provides evidence of their capacity to degrade cellulose. Given the recent interest in cellulosic biofuels, understanding how large-scale and rapid plant biomass degradation occurs in a highly evolved insect herbivore is of particular relevance for bioenergy
Circulating microRNAs in sera correlate with soluble biomarkers of immune activation but do not predict mortality in ART treated individuals with HIV-1 infection: A case control study
Introduction: The use of anti-retroviral therapy (ART) has dramatically reduced HIV-1 associated morbidity and mortality. However, HIV-1 infected individuals have increased rates of morbidity and mortality compared to the non-HIV-1 infected population and this appears to be related to end-organ diseases collectively referred to as Serious Non-AIDS Events (SNAEs). Circulating miRNAs are reported as promising biomarkers for a number of human disease conditions including those that constitute SNAEs. Our study sought to investigate the potential of selected miRNAs in predicting mortality in HIV-1 infected ART treated individuals. Materials and Methods: A set of miRNAs was chosen based on published associations with human disease conditions that constitute SNAEs. This case: control study compared 126 cases (individuals who died whilst on therapy), and 247 matched controls (individuals who remained alive). Cases and controls were ART treated participants of two pivotal HIV-1 trials. The relative abundance of each miRNA in serum was measured, by RTqPCR. Associations with mortality (all-cause, cardiovascular and malignancy) were assessed by logistic regression analysis. Correlations between miRNAs and CD4+ T cell count, hs-CRP, IL-6 and D-dimer were also assessed. Results: None of the selected miRNAs was associated with all-cause, cardiovascular or malignancy mortality. The levels of three miRNAs (miRs -21, -122 and -200a) correlated with IL-6 while miR-21 also correlated with D-dimer. Additionally, the abundance of miRs -31, -150 and -223, correlated with baseline CD4+ T cell count while the same three miRNAs plus miR- 145 correlated with nadir CD4+ T cell count. Discussion: No associations with mortality were found with any circulating miRNA studied. These results cast doubt onto the effectiveness of circulating miRNA as early predictors of mortality or the major underlying diseases that contribute to mortality in participants treated for HIV-1 infection
Development and Validation of a Risk Score for Chronic Kidney Disease in HIV Infection Using Prospective Cohort Data from the D:A:D Study
Ristola M. on työryhmien DAD Study Grp ; Royal Free Hosp Clin Cohort ; INSIGHT Study Grp ; SMART Study Grp ; ESPRIT Study Grp jÀsen.Background Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice. Methods and Findings A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with >= 3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1: 393 chance of developing CKD in the next 5 y in the low risk group (risk score = 5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1,702 (95% CI 1,166-3,367); NNTH was 202 (95% CI 159-278) and 21 (95% CI 19-23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506-1462), 88 (95% CI 69-121), and 9 (95% CI 8-10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor. The Royal Free Hospital Clinic Cohort included 2,548 individuals, of whom 94 individuals developed CKD (3.7%) during 18,376 PYFU (median follow-up 7.4 y, range 0.3-12.7 y). Of 2,013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8,452 PYFU (median follow-up 4.1 y, range 0.6-8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria. Conclusions Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.Peer reviewe
The origin of the genus Cannabis
Dissertation - University of Veterinary Medicine Vienna - 2022
The full text is only available to university members. Please log in!Cannabis sativa L. belongs to the small family of Cannabaceae, which comprises twelve genera with Humulus as sister genus. The genus Cannabis is monotypic and it has been distributed globally as one of the oldest known crop plants. The use of C. sativa can be characterized as multi-purpose of fibre for paper, textile or construction materials, as seeds for food and feed and the female inflorescence as medicine, and psychotropic drug. Chloroplast markers (cp markers) are an useful instrument for Cannabis sativa to study relationships of accessions between different geographic origins. In an alignment of three published plastomes 38 chloroplast polymorphisms were identified from which eight cp markers were used to study relationships of 53 cannabis accessions by HRMA. The marker set could distinguish six haplotypes (âAâ to âFâ) in the cannabis collection, where haplotypes âAâ and âFâ dominated with 34% and 50% of the individuals, respectively. A majority of populations (37) were homogeneous regarding the haplotype, twelve accessions were constituted of two haplotypes and four accessions of three haplotypes. Most of the European fibre cultivars consisted of the âFâ-type, some were mixed âA/Fâ-types. The Italian âCarmagnola in Selezioneâ was exceptional in being a pure âAâ-type. In the heterogenous populations, expected heterozygosity ranged from 0.06 to 0.41. The populations were well differentiated by this marker set locating 79% of the variation among populations (AMOVA). Comparying the results with plastomes from the closest related genus Humulus, haplotype âBâ could be identified as haplotype of the common ancestor of both genera. The haplotype âBâ is uncommon with a frequency of only 4% in the populations analysed. Unfortunately, the sincere geographic origin of most samples was unclear. However, amongst all published plastomes, only two were classified as haplotype âBâ, both pointing independently back to Yunnan province (China), indicating Yunnan as the region of origin of the genus Cannabis. Both popular recreational drugs âmarijuanaâ as well as âhashishâ are prohibited by law in many parts of the world and the use is often punished rigorously. Although the policy of decriminalization for recreational use is increasing slowly in western countries primarily, this kind of consumption of C. sativa is still leading to law enforcement throughout the globe with partially severe consequences. If the origin of confiscated illegal drugs could be found out via harmonized molecular genetic methods, it would potentially speed up even cross-national criminal prosecution.Dissertation - VeterinĂ€rmedizinische UniversitĂ€t Wien - 2022
Aus rechtlichen GrĂŒnden sind nicht alle Teile dieser Arbeit frei zugĂ€nglich. Der Zugriff auf den elektronischen Volltext ist auf Angehörige der VeterinĂ€rmedizinischen UniversitĂ€t Wien beschrĂ€nkt. Bitte einloggen!Cannabis sativa L. gehört zur kleinen Familie der Cannabaceae, die zwölf Gattungen mit Humulus als Schwestergattung umfasst. Die Gattung Cannabis ist monotypisch und als eine der Ă€ltesten bekannten Nutzpflanzen weltweit verbreitet. Die Verwendung von C. sativa kann als Mehrzweckfaser fĂŒr Papier, Textilien oder Baumaterialien, als Saatgut fĂŒr Nahrungs- und Futtermittel und die weiblichen BlĂŒtenstĂ€nde als Arzneimittel charakterisiert werden. Chloroplasten Marker (cp Marker) sind ein brauchbares Instrument um Verwandtschaften von Cannabis sativa zwischen unterschiedlichen geographischen UrsprĂŒngen zu studieren. In einer Angleichung von drei veröffentlichten Plastomen wurden 38 Chloroplasten- Polymorphismen identifiziert, von denen acht cp-Marker verwendet wurden, um die Beziehungen von 53 Cannabisakzessionen mit der hochauflösenden Schmelzkurvenanalyse (HRMA) zu untersuchen. Der Markersatz konnte sechs Haplotypen (âAâ bis âFâ) in der Cannabissammlung unterscheiden, wobei die Haplotypen âAâ und âFâ mit 34% bzw. 50% der Individuen dominierten. Eine Mehrheit der Populationen (37) war hinsichtlich des Haplotyps homogen, zwölf Akzessionen bestanden aus zwei Haplotypen und vier Akzessionen aus drei Haplotypen. Die meisten europĂ€ischen Fasersorten bestanden aus dem âFâ-Typ, einige waren gemischte âA/Fâ-Typen. Der italienische âCarmagnola in Selezioneâ war auĂergewöhnlich, da er ein reiner âAâ-Typ war. In den heterogenen Populationen reichte die erwartete Heterozygotie von 0,06 bis 0,41. Die Populationen waren durch diesen Markersatz, der 79% der Variation zwischen den Populationen (AMOVA) lokalisierte, gut differenziert. Durch den Vergleich mit Plastomen der am nĂ€chsten verwandten Gattung Humulus konnte der Haplotyp âBâ als Haplotyp des gemeinsamen Vorfahren beider Gattungen identifiziert werden. Der Haplotyp âBâ ist mit einer HĂ€ufigkeit von nur 4% in den analysierten Populationen selten. Leider war die wahre geografische Herkunft der meisten Proben unklar. Von allen veröffentlichten Plastomen wurden jedoch nur zwei als Haplotyp âBâ klassifiziert, die beide unabhĂ€ngig voneinander auf die Provinz Yunnan (China) zurĂŒckweisen, was Yunnan als Ursprungsregion der Gattung Cannabis anzeigt. Sowohl die beliebten Freizeitdrogen âMarihuanaâ als auch âHaschischâ sind in vielen Teilen der Welt gesetzlich verboten und der Konsum wird oft rigoros bestraft. Obwohl die Politik der Entkriminalisierung fĂŒr den Freizeitkonsum vor allem in westlichen LĂ€ndern langsam zunimmt, fĂŒhrt diese Art des Konsums von C. sativa immer noch zu einer weltweiten Strafverfolgung mit teilweise schwerwiegenden Folgen. Wenn die Herkunft beschlagnahmter illegaler Drogen durch harmonisierte molekulargenetische Methoden ermittelt werden könnte, wĂŒrde dies möglicherweise sogar die lĂ€nderĂŒbergreifende Strafverfolgung beschleunigen.Dissertation - University of Veterinary Medicine Vienna - 2022
The full text is only available to university members. Please log in!Cannabis sativa L. belongs to the small family of Cannabaceae, which comprises twelve genera with Humulus as sister genus. The genus Cannabis is monotypic and it has been distributed globally as one of the oldest known crop plants. The use of C. sativa can be characterized as multi-purpose of fibre for paper, textile or construction materials, as seeds for food and feed and the female inflorescence as medicine, and psychotropic drug. Chloroplast markers (cp markers) are an useful instrument for Cannabis sativa to study relationships of accessions between different geographic origins. In an alignment of three published plastomes 38 chloroplast polymorphisms were identified from which eight cp markers were used to study relationships of 53 cannabis accessions by HRMA. The marker set could distinguish six haplotypes (âAâ to âFâ) in the cannabis collection, where haplotypes âAâ and âFâ dominated with 34% and 50% of the individuals, respectively. A majority of populations (37) were homogeneous regarding the haplotype, twelve accessions were constituted of two haplotypes and four accessions of three haplotypes. Most of the European fibre cultivars consisted of the âFâ-type, some were mixed âA/Fâ-types. The Italian âCarmagnola in Selezioneâ was exceptional in being a pure âAâ-type. In the heterogenous populations, expected heterozygosity ranged from 0.06 to 0.41. The populations were well differentiated by this marker set locating 79% of the variation among populations (AMOVA). Comparying the results with plastomes from the closest related genus Humulus, haplotype âBâ could be identified as haplotype of the common ancestor of both genera. The haplotype âBâ is uncommon with a frequency of only 4% in the populations analysed. Unfortunately, the sincere geographic origin of most samples was unclear. However, amongst all published plastomes, only two were classified as haplotype âBâ, both pointing independently back to Yunnan province (China), indicating Yunnan as the region of origin of the genus Cannabis. Both popular recreational drugs âmarijuanaâ as well as âhashishâ are prohibited by law in many parts of the world and the use is often punished rigorously. Although the policy of decriminalization for recreational use is increasing slowly in western countries primarily, this kind of consumption of C. sativa is still leading to law enforcement throughout the globe with partially severe consequences. If the origin of confiscated illegal drugs could be found out via harmonized molecular genetic methods, it would potentially speed up even cross-national criminal prosecution