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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Förvar och rätten till frihet för brottsutvisade utlänningar

Fauvrelle, Marc Robert January 2018 (has links)
Under Swedish law, an alien convicted of an offence punishable by imprisonment may be sentenced to deportation if there is reason to assume that the alien will reoffend, or if the offence is so serious that the alien should not be permitted to stay. Upon release, the alien may be held in immigration detention for the purpose of enforcing the deportation order. While detention is generally subject to maximum time limits, criminal deportees face indefinite detention. This exceptional treatment raises questions about the proper purpose of immigration detention and respect for the right to liberty. This paper investigates and critically analyses the Swedish regulatory framework for the detention of criminal deportees from a human rights perspective. It reveals how the alien’s criminal record and assumptions about the risk for reoffending play adecisive role both in the decision to detain and the length of detention. The right to liberty, which protects the individual against illegal and arbitrary detention, does not prohibit the use of immigration detention for crime prevention purposes, provided it is subsidiary to the primary purpose of enforcing the deportation order. Administrative detention is, however, arguably an inappropriate tool for the prevention of crime. Moreover, the Swedish legislation lacks a coherent and satisfactory basis. A thorough enquiry into the use of immigration detention as a crime prevention measure is necessary, to analyse data on the detention of criminal deportees and examine how criminal law measures could be more appropriately used to counter serious threats to public order, without unnecessary encroachment on the right to liberty.
202

Implementation of project based learning in a training package context

Wright, Julie, j.wright@rmit.edu.au January 2008 (has links)
Training Packages form the basis upon which practitioners in the Vocational Education and Training (VET) sector in Australia develop their pedagogical processes. As workplaces adapt their practices to compete globally, demand for skilled and knowledgeable workers places pressure on institutional training providers such as TAFE to develop training programs that support the acquisition of higher order thinking skills in graduates. Using a competence based framework as a backdrop, the research centres on the notion of the place of Project Based Learning in a Training Package context. The research proposes that learning through projects is an effective means of integrating Training Package outcomes with an instructional model that engages learners in independent, flexible and reflective learning. The research was conducted retrospectively from a case study of an AQF Level 6 Textile, Clothing and Footwear Training Package Program at RMIT University TAFE. An Action Research approach underpins the investigation, resulting in the profiling of teaching, learning and assessment as areas in need of further examination. These defining themes are explored in the context of the Project Based Learning model developed at RMIT, with consideration given to the potential for broader application. The discussion concludes with a theoretical review of the new understandings of pedagogy. The study aims to establish that a constructive alignment exists between the behaviourist approach of Training Packages and the more constructivist theories behind Project Based Learning; rendering it a suitable instructional model that meets the needs of 21st century learners.
203

Beruf und Erziehung

29 November 2013 (has links) (PDF)
Im September 2013 hielt die Sektion Berufs- und Wirtschaftspädagogik der Deutschen Gesellschaft für Erziehungswissenschaften ihre letztmalige Herbsttagung als Gast an der TU Chemnitz ab. Dieser Band beinhaltet die Abstracts aller auf der Tagung gehaltenen Vorträge; mit einem Geleitwort des Veranstalters und Herausgebers.
204

A New Perspective into Languages for Specific Purposes (LSP) Syllabus Design : Target language learningpromoting thedevelopment of refugee employability competencies

Capocchi Ribeiro, Maria Alice de Fatima January 2021 (has links)
This thesis reports on a meta-analysis of the most relevant employabilitycompetencies to foster refugees’ labour integration which may be potentiallyleveraged through a target language for specific purposes (LSP)MOOCsyllabus. Italso suggests to group the thus identified employability competencies into threecategories tofurther supportLSPMOOC syllabus design and implementation.Themethodology of meta-analysis was based on Cooper’s (2017) five-stage model andguided by exploratory data analysis (EDA) of a dedicated research corpus that wasspecifically tailored for this study. Three data mining tools were used to performnatural language pre-processing and pattern extraction, directed by key terms(employability, competency, competencies, skill, ability, abilities, vocational,refugee,andlabour) used in various query combinations and limiters. IterativeEDApost-processing of metadata generated by these tools, based ontheoretical andsemantic sorting and integration, led to 21 re-aggregated clusters of employabilitycompetencies and the suggested categories for grouping them.The present studyshows that the broader capillarity of data and text mining tools, as well as ofEDA,can contribute toa more encompassing view of employability competencies and oftheLSP as a tool-competency, hence to a greater capillarity ofcompetency-basedVET(Vocational Education and Training) syllabus design, particularly the proposedinnovative type ofLSPMOOC syllabus. / <p>Examination Seminar held by Zoom given that it was a Distance Programme</p>
205

Viral metagenomics and phylogenomics for One Health

Silverj, Andrea 25 March 2024 (has links)
In recent years, the world has faced major health challenges, from the rise of antibiotic resistance to the emergence of new pathogens with pandemic potential. This highlights the importance of considering human health as inextricably intertwined with that of other animals and the environment in which they live. This paradigm is known as “One Health”, which is the integration of environmental sciences, veterinary science, and medicine. Within this perspective, viruses, the most abundant biological entities on Earth, play a central role in connecting different organisms, deeply influencing the health of their hosts. Despite their great importance, most viruses are still poorly understood, mainly because of the technical and economic limitations posed by isolation, cultivation, and single colony sequencing. However, recently developed genomic technologies offer a cheaper and more sensitive alternative to study viruses, allowing a better integration of data from various sources and making it possible to explore how they circulate among different hosts and environments. In this thesis, I hypotesise that, by combining different classes of genomic methods with One Health practices, it is possible to reveal much more of the entire picture of viral diversity and evolution that by simply using them in a separated way. I show that this is the case for each one of the scientific questions addressed in this work, which are organised in three main chapters: - In the second chapter I analysed 22 metatranscriptomes from tick samples from different parts of Italy, obtaining a set of 91 viral contigs for which I reconstructed the phylogeny, with the aim to identify the presence of possible pathogens and characterise the unexplored viral diversity in the country. This analysis not only clarified the molecular epidemiology of well-known pathogens such as Tick-borne encephalitis virus, but also allowed the discovery of at least 10 novel viral species. - In the third chapter, I investigated the origin and spread of West Nile virus, an emerging pathogen causing neurological disease worldwide. The goal was to expand the current knowledge of this virus by increasing the number of sequenced genomes and to reconstruct how the virus moved between Africa and Europe. Phylogeographic and phylodynamic methods showed that this pathogen originated in Africa and repeatedly invaded the European continent, revealing the dynamics of its evolution through space and time. - In the last chapter, I contributed to obtaining a set of DNA phages assembled from human microbiomes and viromes by manual curation and comparative genomics and developed a new approach to study their evolution in relation to their bacterial hosts. I found that the strength of co-phylogenetic patterns between viruses and their hosts is generally weak, suggesting that their ecological relationships emerge on short evolutionary timescales. Taken together, these results show how the integration of viral metagenomics and phylogenomics in One Health is essential to answer fundamental questions about the diversity of viruses and how they spread and evolve. Furthermore, the methods and protocols developed in these studies can be applied to similar cases, allowing a systematic exploration of many other datasets to expand our knowledge of the virosphere. This information can be used to implement containment strategies, public health policies, therapies, and biotechnologies.
206

Studie- och yrkesvägledning i grundskolan - “De vet inte vad vi gör!” / Study- and career guidance in primary school –“They don´t know what we do!”

Aveling, Mattias, Kristensson, Hugo January 2024 (has links)
Syftet med studien är att utforska hur implementeringen av studie- och yrkesvägledning i tidigt skede på grundskolor främjar elevers framtida studie och yrkesval. Då studie- och yrkesvägledningen är ett ämne som ofta bortprioriteras på grund av diverse anledningar innebär det att det ofta implementeras i ett sent stadium. Studien bidrar med en förståelse för problemområdet. Undersökningen har genomförts utifrån kvalitativ metod och semistrukturerade intervjuer. Därför har semistrukturerade intervjuer genomförts med sju utbildade studie- och yrkesvägledare som arbetar inom grundskolan.      Studiens frågeställningar är: -Hur arbetar SYV med studie- och yrkesvägledning i yngre årskurser? -Hur involverad är skolans ledning i studie- och yrkesvägledningen? -Vilken betydelse har tidig implementering av studie- och yrkesvägledning på elevers valkompetens? För att besvara dessa frågor utgår studien från informanternas svar. Intervjuerna har analyserats med hjälp av Gottfredsons teori om begräsningar och kompromisser där begreppen självuppfattning, yrkesstereotyper, mentala kartor över yrken, omskrift och kompromiss används. Hodkinson och Sparkes begrepp handlingshorisont varvas med dessa begrepp.      Studiens huvudresultat visar att implementeringen av studie- och yrkesvägledning i tidigt skede bidrar till en säkerhet hos eleverna samtidigt som deras valkompetens ökar. De informanter som integrerar studie- och yrkesvägledningen tidigt belyser resultatet av det och de informanter som inte integrerar det tidigt i dagsläget uttrycker en gemensam önskan kring att få göra det en dag. Tidsbrist och okunskap hos skolans ledning är återkommande faktorer som påverkar den tidiga implementeringen.
207

Nuove indagini sul metabolismo e la risposta immunitaria dalla messa in asciutta all'avvio di lattazione / NEW INSIGHT ON METABOLISM AND THE IMMUNE RESPONSE FROM DRY-OFF TO EARLY LACTATION

MEZZETTI, MATTEO 03 April 2019 (has links)
Il sistema immunitario è costituito da una varietà di cellule, molecole e processi biologici che interagiscono per prevenire le invasioni microbiche, riconoscere le molecole estranee ed eliminare le fonti esistenti di lesioni cellulari, ripristinando le normali funzioni tissutali una volta risolto il problema. L'immunità innata è la prima linea di difesa contro le invasioni di agenti patogeni. Nelle vacche da latte, il suo funzionamento subisce gravi alterazioni durante il periodo di transizione (TP). In questa fase è stata segnalata una compromissione delle funzioni delle cellule polimorfonucleate (PMN) correlate alla produzione di metaboliti reattivi dell'ossigeno (ROM), all’attività della mieloperossidasi (MPO), alla chemiotassi e alla fagocitosi. I PMN bovini hanno un alterata espressione dei geni codificanti per tali funzioni tra -1 e 2 settimane dal parto, rispetto al livello rilevato 4 settimane dopo il parto per gli stessi geni. La causa esatta delle disfunzioni immunitarie che si verificano nel periparto non è mai stata chiaramente identificata. In esse possono contribuire diversi fattori, principalmente imputati alle alterazioni metaboliche tipiche del periparto (cambiamenti nell’assetto ormonale, limitazione della risposta immunitaria materna al fine di mantenere la gravidanza, alterazioni nel bilancio energetico e stato di stress ossidativo). Tuttavia, la durata e l’entità delle disfunzioni immunitarie può aumentare qualora subentri uno stato di squilibrio fisiologico (PI). In tali condizioni, le alterazioni metaboliche del periparto sfuggono al controllo dei meccanismi omeostatici e omeoretici, ed una infiammazione sistemica è la conseguenza frequente di questo squilibrio. Lo stato infiammatorio sistemico è scatenato da un aumento dei livelli di citochine proinfiammatorie (PIC), che è collegato ad un aumento della temperatura corporea al parto, e che tipicamente inficia le funzionalità epatiche, modificando le priorità anaboliche dell'organo in fase di inizio lattazione. A seguito di tale slittamento, il fegato produce più α-globuline, note come proteine positive di fase acuta (+APP), cioè aptoglobina, ceruloplasmina e siero amiloide alfa (SAA). Al contrario, riduce la sintesi di albumina, retinol binding protein (RBP), paraoxonasi (PON) e lipoproteine, note come proteine negative di fase acuta (-APP), e sequestra minerali, quali zinco e ferro, dal flusso ematico. L'infiammazione porta all'attivazione dei PMN, mentre la ridotta competenza immunitaria comunemente riportata in TP è stata associata ad un effetto opposto sui leucociti. Pertanto, questi dovrebbero essere considerati come due fenomeni distinti, ma lo stato di PI potrebbe essere considerato un denominatore comune, direttamente correlato al rischio di patologie in avvio di lattazione. Le strategie nutrizionali per ottimizzare l'immunità delle vacche da latte durante il TP dovrebbero quindi essere focalizzate sulla riduzione del grado di PI correlato al parto. Tra tali strategie nutrizionali, dovrebbe essere presa in considerazione la corretta gestione delle fonti energetiche per adattarle alle variazioni dei fabbisogni. Inoltre, il profilo degli acidi grassi delle fonti lipidiche può contribuire nel modificare le funzioni immunitarie. Infine, la somministrazione di prodotti supplementari con attività antiossidanti o antinfiammatorie, così come di specie donatrici di gruppi metilici, potrebbero essere strategie utili a favorire la funzionalità immunitaria delle bovine durante il TP. In una prospettiva più ampia, sebbene strategie nutrizionali e supplementi possano talora mitigare le alterazioni immunitarie, possiamo concludere che l'adozione di pratiche volte a minimizzare il PI durante il periodo di transizione sia la strategia più efficace per prevenire le disfunzioni. Al fine di chiarire il legame tra le alterazioni che si verificano nel periparto e le disfunzioni immunitarie delle bovine da latte sono stati condotti tre esperimenti. Bovine di razza frisona sono state alloggiate in poste individuali a stabulazione fissa e monitorate regolarmente per le condizioni corporee (BCS), il peso (BW), l'assunzione di alimenti (DMI), la produzione di latte (MY) e il tempo di ruminazione. Campioni di sangue sono stati raccolti regolarmente per valutare un ampio profilo ematochimico e per testare le funzioni dei globuli bianchi mediante stimolazioni ex-vivo. Inoltre, la diapedesi dei PMN è stata testata in vivo mediante test della carragenina e sono stati raccolti campioni di rumine a 30 giorni dal parto (DFC). Il primo esperimento era volto a chiarire le cause dei cambiamenti metabolici che si verificano al momento della messa in asciutta, ed il contributo del livello produttivo in tali alterazioni. Infatti, i profondi cambiamenti nell’alimentazione, gli adattamenti gastrointestinali, del metabolismo e dei parametri immunitari che si verificano nelle bovine alla messa in asciutta sono note scatenare il rilascio di cortisolo, indurre segnali di infiammazione sistemica ed alterare il bilancio redox. Produzioni di latte elevate al momento della messa in asciutta hanno un ruolo nell'aggravare tali condizioni. Nel nostro studio, un gruppo di 13 bovine è stato asciugato a 55 giorni dalla data prevista per il parto. Gli animali sono stati divisi in due gruppi in base alla produzione media dell'ultima settimana di lattazione, assumendo un cut-off di 15 kg * d-1: bassa (LM; 6 animali) e alta produzione (HM; 7 animali). I dati sono stati sottoposti ad ANOVA utilizzando un modello per misure ripetute, assumendo il livello produttivo al termine della lattazione, il tempo e la loro interazione come effetti fissi. L'aumento delle quantità di fibra nella razione di asciutta ha ridotto la DMI e aumentato il tempo di ruminazione. La migrazione dei leucociti nella ghiandola mammaria per contribuire alla fase di involuzione ha ridotto la loro abbondanza nel sangue e aumentato la loro attività. Tale attivazione dei leucociti nella mammella ha aumentato l'abbondanza di specie reattive dell’azoto nel plasma e innescato un'infiammazione sistemica in tutti gli animali (aumento delle +APP e riduzione delle -APP). Tale infiammazione ha compromesso le funzioni epatiche (aumento delle concentrazioni di gamma-glutamil transferasi -GGT- bilirubina e fosfatasi alcalina -ALP-). Sia la produzione di specie dell’azoto che lo stato infiammatorio sistemico hanno contribuito all'esaurimento degli antiossidanti circolanti (gruppi tiolici -SHp-, tocoferolo, β-carotene, potere antiossidante ferrico riducente -FRAP- e capacità antiossidante contro specie reattive dell'ossigeno -ORAC-). Gli animali con una produzione più elevata alla messa in asciutta hanno mostrato la peggiore condizione, probabilmente per i più profondi cambiamenti metabolici che hanno affrontato dopo l'interruzione delle mungiture, e per la fase involutiva verosimilmente più dispendiosa. Questo studio evidenzia la messa in asciutta come una fase critica per gestire la salute delle vacche da latte, e suggerisce un potenziale legame della messa in asciutta con le alterazioni delle funzioni immunitarie che si verificano nel periparto. Nel secondo esperimento si sono cercati di identificare i cambiamenti del sistema immunitario che precedono l'insorgenza della chetosi, al fine di chiarire il loro ruolo nella comparsa della malattia. Pertanto, 13 bovine sono state monitorate tra -48 e 35 DFC e suddivise in due gruppi sulla base dei loro livelli plasmatici di beta idrossibutirrato (BHB): inferiore (CTR, 7 animali) o superiore a 1,4 mMol / L (KET; 6 animali). I dati sono stati sottoposti ad ANOVA utilizzando un modello per misure ripetute, assumendo lo stato di salute, il tempo e la loro interazione come effetti fissi. Le vacche KET hanno avuto una maggiore attivazione del sistema immunitario prima del parto (maggiori concentrazioni plasmatiche di PIC, MPO e specie ossidanti e maggiori produzione di interferone gamma in risposta alla stimolazione con Mycobacterium avium) alterazioni della funzionalità epatica (più alta concentrazione sanguigna di GGT) e minori minerali plasmatici. Elevati livelli plasmatici di NEFA, BHB e glucosio nelle vacche KET suggeriscono uno stato di insulinoresistenza e una marcata mobilizzazione del grasso corporeo durante il periodo di asciutta. Tali andamenti dei parametri relativi al metabolismo energetico durante l’asciutta sono stati associati alla riduzione della DMI al momento del parto e al peggioramento del bilancio energetico negativo ad avvio lattazione. Ciò ha causato a sua volta una riduzione di MY e accresciuto ulteriormente la mobilizzazione dei grassi in avvio di lattazione. Compromissione della funzionalità epatica e attivazione dei leucociti durante il periodo di asciutta hanno determinato una marcata risposta infiammatoria di fase acuta nelle vacche KET dopo il parto (maggiori concentrazioni di +APP minori concentrazioni di RBP), ed ulteriormente compromesso la funzionalità epatica (maggiori concentrazioni di glutammato-ossalacetato transaminasi -AST-GOT- e bilirubina). I leucociti delle vacche KET hanno mostrato ridotte funzioni infiammatorie dopo stimolazione ex-vivo con lipopolisaccaridi batterici (minore produzione di PIC e maggiore produzione di lattato). Queste alterazioni potrebbero essere guidate dall'azione combinata dei metaboliti legati alla mobilizzazione dei lipidi e delle azioni antinfiammatorie volte a prevenire un'infiammazione eccessiva. Ciò suggerisce che le alterazioni dei parametri immunitari osservate prima del parto siano altamente correlate con la probabilità di sviluppare chetosi in avvio di lattazione. Nel terzo esperimento è stato somministrato un prodotto immunostimolante dalla comprovata efficacia nel migliorare le funzioni leucocitarie degli animali immunodepressi e nel ridurre l'incidenza delle malattie infettive delle bovine ad inizio lattazione. La sua modalità di azione non è mai stata chiarita, e un’indagine approfondita sul suo effetto metabolico potrebbe evidenziarne l’efficacia anche nei confronti dei disordini metabolici del periodo di transizione. Pertanto, un gruppo di10 bovine è stato monitorato da -62 a 42 DFC. Il gruppo trattato (TRT, 5 animali) ha ricevuto 32,5 g di Omnigen-AF® (Phibro Animal Health Corporation) due volte al giorno (65 g d-1), mentre il gruppo di controllo (CTR, 5 animali) non ha ricevuto alcun supplemento. I dati sono stati sottoposti ad ANOVA utilizzando un modello per misure ripetute, assumendo il trattamento, il tempo e la loro interazione come effetti fissi. La somministrazione dell’immunostimolante alla messa in asciutta non ha influenzato BW, BCS, MY, composizione del latte e del fluido ruminale e nemmeno modificato la concentrazione di neutrofili del sangue. Tuttavia, ha aumentato il tempo di ruminazione e migliorato il metabolismo energetico dopo il parto (concentrazioni di NEFA e BHB inferiori). Le bovine TRT avevano maggiori concentrazioni ematiche di linfociti e i loro leucociti avevano una maggiore efficienza nel rispondere alla stimolazione con lipopolisaccaridi batterici (produzione di lattato inferiore e minore consumo di glucosio). Nonostante questi effetti positivi sulle cellule immunitarie, l'immunostimolante non ha influenzato le concentrazioni di +APP dopo il parto. Inoltre, l’immunostimolante ha ridotto le concentrazioni di albumina, PON e antiossidanti dopo il parto, suggerendo la compromissione di alcune funzioni epatiche negli animali trattati. Tuttavia, la mancanza di qualsiasi effetto sui biomarcatori di funzionalità (bilirubina) e danno epatico (GGT, AST-GOT, ALP) smentisce una reale compromissione delle attività epatiche a seguito del trattamento. Gli effetti positivi nel favorire il recupero delle funzioni del rumine, riducendo la mobilizzazione dei grassi corporei dopo il parto, suggeriscono che l'immunostimolante sia una strategia efficace nella prevenzione dei disturbi metabolici del periodo di transizione. / Immune system is made of a variety of cells, molecules and biological processes that interacts to prevent microbial invasions, recognize foreign molecules and eliminate existing sources of cellular injuries to restore tissues to their normal functions once problem has been solved. Innate immunity is the primary defense line against pathogens invasions. Its functioning typically undergoes severe alterations during transition period (TP) of dairy cows. An impairment of polymorphonuclear cells (PMN) functions related to reactive oxygen metabolites (ROM) production, myeloperoxidase (MPO) activity, chemotaxis and phagocytosis has been reported in this phase. Bovine PMN have an altered abundance in mRNA transcripts encoding for such functions between -1 and 2 weeks from calving, in comparison to the level found at 4 weeks after calving for the same genes. The exact cause of immune dysfunctions occurring in peripartum has never been clearly identified. Reduced immune competence could arise from the interaction of different factors affected from the typical peripartum trends (i.e. changes in endocrine asset, limitations of maternal immune responses against the allogeneic conceptus, alterations in energy balance and oxidative stress status). Nevertheless, its duration could be modified when peripartal changes exceed the control of homeorhetic and homeostatic mechanisms, leading to the physiological imbalance (PI) condition. Such a condition could also trigger the inflammatory-like status. It consists in a prepartal raise of pro-inflammatory cytokines (PICs) levels, that is linked to a raise in body temperature at calving, and that typically affects liver metabolism, implying severe losses in hepatic functions and a shift of anabolic priority of the organ in early lactation. The liver produces more α-globulins, known as positive acute phase proteins (APP), i.e. haptoglobin, ceruloplasmin and serum amyloid alpha (SAA). Conversely, it reduces the synthesis of albumin, retinol binding protein, paraoxonase (PON) and lipoproteins, known as negative APP and sequesters minerals, as zinc and iron, from blood flow. Inflammation lead to the activation of PMN, while the reduced immune competence commonly reported in TP has been associated to an opposite effect on leukocytes. Thus, these should be considered as two distinct phenomena, but they could arise from a common cause with a different magnitude and duration. Nutritional strategies to optimize dairy cow’s immunity during TP should be focused on reducing the PI degree related to calving, as this condition could be referred as a common denominator between immune dysfunction and diseases causes. Among such nutritional strategies, the correct management of energy sources to fit with altered requirements should be considered. Furthermore, fatty acids profile of lipid sources administered could also modify immune functions. Finally, the administration of supplementary products exerting antioxidant or anti-inflammatory activities, as well as methyl donors species, could be beneficial for dairy cows immunity in TP. In a wider perspective, although feed additives and nutritional strategy could be effective in mitigate immune alterations, we can conclude that adoption of proper management practices aimed to avoid PI condition in peripartal period of dairy cows could be the most effective strategy to prevent dysfunctions. Three experiments have been designed to elucidate the linkage between sudden changes occurring in peripartum and immune alterations in dairy cows. Throughout such experiments Holstein dairy cows were housed in tied stalls and monitored regularly for body condition score (BCS), body weight (BW), dry matter intake (DMI), milk yield (MY) and rumination time. Blood samples were collected regularly to assess a wide hematochemical profile and to test white blood cell functions through ex-vivo challenges. Furthermore, PMN diapedesis has been tested in-vivo through a carrageenan-skin test and rumen samples were collected at 30 days from calving (DFC). The first experiment was aimed in investigate the main causes of metabolic changes occurring at dry-off and the contribution of MY in such alterations. In fact, dry-off is related to deep changes in feeding behavior, gastro intestinal adaptations, metabolism and immune parameters in high-yielding cow’s career. Indeed, the release of cortisol, signals of systemic inflammation and altered redox balance have been reported immediately after milking interruption, and high MY have a role in aggravating such conditions. In our study, a group of 13 Holstein dairy cows were dried off at 55 days from expected calving day, and regularly monitored from -7 to 34 days from dry-off (DFD). Animals were retrospectively divided in two groups according to their average MY in the last week of lactation, assuming a cut-off of 15 kg*d-1: low MY (6 cows) and high MY (7 cows). Data were submitted to ANOVA using a mixed model for repeated measures including MY at dry-off, time and their interaction as fixed effects. Increased fiber amounts of dry ration reduced DMI and increased rumination time. Leukocytes migration into mammary gland to contribute in the involution phase decreased their abundance in blood at dry-off, and their activity. Such activation of leukocytes at mammary site increased the abundance of nitrogen species in plasma and triggered a systemic inflammation in all the animals, as reflected from increased concentrations of positive and reduced concentrations of negative APPs. Such inflammation impaired liver functions, as suggested from the increased gamma-glutamyl transferase (GGT), bilirubin and alkaline phosphatase (ALP) concentrations. Both the production of nitrogen species and the systemic inflammatory status contributed in the depletion of antioxidant system in blood (thiol groups -SHp-, tocopherol, β-carotene, ferric reducing antioxidant power -FRAP- and oxygen reactive antioxidant capacity -ORAC-). Animals with higher MY at dry-off showed the worst condition, likely for the deeper metabolic changes they faced at milking interruption, and to the greater amount of mammary parenchyma to be reabsorbed. This study highlights the dry-off as a thorny point to manage dairy cows’ health and depose for a relationship between dry-off and immune alteration that typically occurs at calving. The second experiment was aimed in investigate changes occurring in the immune system prior to ketosis onset to elucidate their role in disease occurrence. Thus, a group of 13 Holstein dairy cows were monitored from -48 to 35 DFC and retrospectively divided into 2 groups basing on their plasma BHB levels: lower (CTR; 7 cows) or higher than 1.4 mMol/L (KET; 6 cows). Data were submitted to ANOVA using a mixed model for repeated measures including health status, time and their interaction as fixed effects. KET cows had a greater activation of the immune system prior to calving (higher plasma concentrations of PICs, myeloperoxidase and oxidant species, and greater interferon gamma responses to Mycobacterium avium) impaired liver functions (higher blood concentration of GGT) and lower plasma minerals. High plasma NEFA, BHB and glucose levels in KET cows suggest an insulin resistance status and a marked mobilization of body fat occurring during dry period. They were also associated to reduced DMI around calving and worse negative energy balance in early lactation. This caused in turn reduced MY and increased fat mobilization in early lactation. Impairment of liver function and activation of leukocytes during the dry period accentuated the acute phase response in KET cows after calving (greater concentrations of positive APPs and lower concentration of retinol binding protein), further impairing liver function (higher blood concentrations of glutamate-oxaloacetate transaminase -AST-GOT- and bilirubin). Leukocytes of KET cows had reduced inflammatory functions after an ex vivo stimulation assay (lower production of PICs and greater production of lactate). These alterations on WBC could be driven by the combined action of metabolites related to the mobilization of lipids and of anti-inflammatory actions aimed to prevent over exuberant inflammation. This suggests that prepartal trends of immune parameters be highly related with the likelihood of developing diseases in early lactation. The third experiment consisted in the administration of Omnigen-AF (OAF), an immune stimulant that is effective in increasing leukocytes functions in immunosuppressed animals and in reducing incidence of infectious diseases in early lactating dairy cows. Its mode of action has never been elucidated, and a wider perspective of its metabolic effect could highlight its effectiveness in facing metabolic disorders of transition period also. Thus, a group of 10 Holstein dairy cows were divided into 2 groups: treated group (TRT; 5 cows) received 32.5 g of Omnigen-AF® (Phibro Animal Health Corporation) twice a day (65 g d-1) as top-dress on the morning and afternoon feeds, while control group (CTR; 5 cows) did not receive any supplementation. From -62 to 42 DFC animals were monitored regularly. Data were submitted to ANOVA using a mixed model for repeated measures including treatment, time and their interaction as fixed effects. Administration of OAF at dry-off did not affect BW, BCS, milk yield, milk and rumen fluid composition, and neither affected blood neutrophils concentrations. Nevertheless, it increased rumination time and improved the energy metabolism after calving (lower NEFA and BHB concentrations). TRT cows had an increased lymphocytes abundance at blood level, and their leukocytes had greater efficiency in facing biological stressors during the peripartum (lower lactate production and lower glucose consumption after a challenge with bacterial lipopolysaccharides). Despite these positive effects on immune cells, OAF did not affect the positive APPs concentrations after calving. A reduced abundance of albumin, PON and antioxidants also occurred with OAF after calving, suggesting some impairment of hepatic functions to occur. Nevertheless, the lack of any effect on main biomarkers related to liver function (bilirubin) and liver damage (GGT, AST-GOT, ALP) dismisses a real impairment of liver activities to occur with OAF. Positive effects in favoring the recovery of rumen functions, reducing mobilization of body fats after calving suggest OAF to be an effective strategy in preventing metabolic disorders of transition period.
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MammOmics™ in Sus scrofa: Studio degli adattamenti genomici alla base dello sviluppo della ghiandola mammaria durante la gravidanza e la lattazione. / Mammomics in sus scrofa: uncovering adaptation underlylng mammary development during pregnancy and lactation

TRAMONTANA, SIMONA 04 February 2009 (has links)
La comprensione dei geni che controllano la crescita, lo sviluppo, e il metabolismo della ghiandola mammaria suina può rivelare potenziali vie metaboliche o di segnale per migliorare l'efficienza di sintesi del latte. Un microarray suino costituito da 13.263 oligonucleotidi (mer 70) è stato utilizzato per lo studio del profilo di trascrizione del tessuto mammario da 4.5 scrofe a -34, -14, -4, 0, 7, 14, 21, e 28 giorni rispetto alla data del parto. ANOVA (FDR ≤ 0.10) ha individuato 2664 geni differenzialmente espressi (DEG) in relazione allo stato fisiologico. L’analisi dei network e delle vie metaboliche ha identificato come funzioni molecolari più affette dallo stato fisiologico: crescita e proliferazione cellulare (548 geni) cellule di segnale(612 geni).La qPCR rimane il metodo migliore per la misurazione dell’ abbondanza mRNA ad alta precisione e per la validazione di dati array. Essenziale per assicurare l'affidabilità della qPCR è la normalizzazione dei dati con l’utilizzo di geni di controllo interno (ICG). Un analisi sulla stabilità dei geni ha identificato, tra i 19 potenziali ICG, API5, VABP, e MRPL39 come i più stabili ICG nel tessuto mammario suini e ha inoltre stabilito che l'uso di tali 3 geni è il più appropriato per il calcolo di un fattore di normalizzazione. I risultati sottolineano l'importanza di una corretta validazione dei controlli interni per qPCR ed evidenziano le limitazioni di utilizzo dell’assenza dell’effetto tempo come unico criterio per la selezione di CIG. / Elucidating genes controlling growth, development, and metabolism of swine mammary glands can reveal potential metabolic or signalling pathways that might help improve efficiency of milk synthesis. A swine microarray consisting of 13,263 oligonucleotides (70 mer) was used for transcript profiling of mammary tissue from 4-5 sows at -34, -14, -4, 0, 7, 14, 21, and 28 d relative to parturition. ANOVA (FDR ≤ 0.10) identified 2,664 differentially expressed genes (DEG) dueto physiological state. Gene network/pathway analysis revealed that cell growth and proliferation (548 genes) and cell signaling (612 genes) were among the most affected molecular functions due to physiological state in DEG. QPCR remains the chosen method for high-precision mRNA abundance analysis and for array data validation. Essential for reliability of qPCR data is normalization using appropriate internal control genes (ICG). Gene stability analysis identified , among 19 potential ICG, API5, VABP, and MRPL39 as the most stable ICG in porcine mammary tissue and indicated that the use of those 3 genes was most appropriate for calculating a normalization factor. Results underscore the importance of proper validation of internal controls for qPCR and highlight the limitations of using absence of time effects as the criteria for selection of appropriate ICG.
209

Den kvantandliga diskursen : En undersökning av nyandlighetens möte med kvantfysiken

Sporrong, Elin January 2012 (has links)
This paper aims to describe and elaborate on a recent discursive change within the new-age movement. Since the seventies and the publishing of speculative popular science books like The Tao of Physics by Fritjof Capra and The self-aware Universe by Amit Goswami, the idea that quantum physics resonates with spirituality has become the topic of hundreds of books and movies. The quantum-spiritual discourse has three distinct ways to approach quantum physics in its discussion on spirituality: The parallelistic approach which emphasizes the similarities between eastern philosophies and modern physics, the monistic-idealistic approach which tells us that mind is the foundation of matter and the scientific spiritual approach which tries to explain spiritual claims scientifically. In the quantum-spiritual discourse, quantum physical phenomena (e.g. non-locality and entanglement) are being called upon to validate metaphysical statements. The primary assumption of the discourse is that the shift of paradigm due to the establishment of modern physics also is a shift of paradigm of spirituality. With the object to examine the common claims made in the discourse, cross-references between spiritual arguments and facts of quantum physics are being made. A discussion is held about the probable influence of the historical context, with particular focus on the monistic evolvement during the late nineteenth century.
210

Vet han att han tror? : En studie av Christer Sturmarks kunskapssyn

Säteraas, Jörgen January 2017 (has links)
The modern swedish atheism is led by Christer Sturmark, chairman of Humanisterna, the swedish humanists. In this essay I study the epistemology of Christer Sturmark to find out on what basis he makes his assumptions about knowledge, faith, belief and his view that scientism is the only way to reach real knowledge. I present a closer historical look at the research about and philosophy of epistemology in general and then I analyze Christer Sturmarks book "Tro och Vetande 3.0 - Upplysning i det 21:a århundradet" and compare the views presented in that book to historical and contemporary philopsohers and religous scholars to extract the epistemology of Christer Sturmark, as it is presented in his book. To gain a more thorough understanding of his epistemolgy, I then compare his view to the swedish churchs´view of God as omnipotent. Finally I present a conclusion about the nature of Christer Sturmarks epistemology, if it is logically consistent and how it relates to the way humans can organize their understanding of the world.

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