Structural and Care Process Improvement of Ward-based Postoperative Care to Optimise Surgical Outcomes

Much of the variation seen in surgical outcomes can be explained by differences in the quality of management of post-operative complications and ward-based care. The surgical ward round (WR) is critical to determining post-operative care and serves as the primary point of interaction between clinician and patient. Despite this, it is an area not subject to training or assessment at present. This thesis demonstrates the high degree of variability which exists in the conduct of WRs. It establishes the link between suboptimal patient assessment and increased risk of preventable post-operative complications. These place patients not only at risk of short-term deterioration, but result in reduced long-term survival as well. In order to quantify WR quality, a novel assessment tool has been developed and validated within a simulated environment. Ward simulation is a nascent branch of simulation which has been only preliminarily explored to date. A simulation environment was developed to take advantage of the known benefits of simulation such as controllability, reproducibility, and recordability, whilst maintaining a high level of fidelity and realism. An evidence-based curriculum for surgical WR training was designed and implemented in a simulation-based course. By focusing on structured generic processes of patient assessment and management, this resulted in significant improvement of trainee performance in routine WRs. To ensure standardised and optimum management of specific conditions, checklists have proven themselves to be of great value in a number of surgical and medical disciplines. Surgical complications are common, yet their management often suboptimal. As part of this thesis, evidence-based protocols for the management of the six most common complications were designed and validated. The implementation of these in a simulation-based randomised, controlled trial has resulted in greatly increased adherence to evidence-based standards of care, as well as improved communication and clinician performance. This thesis explores the variance currently present in surgical ward rounds, and the potentially grave consequences of this for patient outcomes. To date, WRs have been one of the last areas of surgical care still dependent on the Halstedian principle of experiential learning alone. The tools have now been developed with which to assess, improve, and standardise critical structures and care processes in the assessment and management of the post-operative surgical patient. Future implementation of these and integration into surgical curricula will benefit clinician training, patient care, and surgical outcomes alike.Open Acces

Non-Reciprocal Optical Amplification and Phase Shifts in a Nanofiber-Based Atom-Light Interface and a Precise Lifetime Measurement of the Cesium 5D_{5/2} State

Nanophotonische Systeme sind eine leistungsfähige Plattform für die Untersuchung von Licht-Materie-Wechselwirkungen. In solchen Systemen bricht die übliche Beschreibung einer elektromagnetischen Welle als eine Welle, die in Bezug auf ihre Ausbreitungsrichtung transversal polarisiert ist, zusammen. Dies ist auf die Einengung der geführten Lichtfelder zurückzuführen, welche zu einer longitudinalen Komponente der elektromagnetischen Felder führt. In dieser Arbeit nutzen wir dies in Verbindung mit unterschiedlichen Kopplungsstärken von Cäsiumatomen an \sigma^- und \sigma^+ polarisiertes Licht, um das Prinzip neuartiger nicht-reziproker optischer Bauelemente zu demonstrieren. Im ersten Teil dieser Arbeit demonstrieren wir die nicht-reziproke Verstärkung von fasergeführtem Licht mit Hilfe von Raman-Verstärkung durch spinpolarisierte Cäsiumatome, die an die Nanofasertaille eines verjüngten Faserabschnitts gekoppelt sind. Wir zeigen, dass unser neuartiger Mechanismus kein externes Magnetfeld benötigt und dass wir die Richtung der Verstärkung vollständig über den atomaren Spinzustand kontrollieren können. Darüber hinaus nutzen wir die chirale Licht-Materie-Wechselwirkung in unserem System, um einen nicht-reziproken antisymmetrischen optischen Phasenschieber zu realisieren. Diese Ergebnisse tragen zur Etablierung einer neuen Klasse von spin-gesteuerten, nicht-reziproken integrierten optischen Bauelementen bei und können den Aufbau komplexer optischer Netzwerke vereinfachen. In einem weiteren Forschungsprojekt tragen wir zum grundlegenden Verständnis von Atomen bei, indem wir die Lebensdauer eines angeregten Cäsiumzustands präzise messen. Wir messen die Lebensdauer des Cäsium 5D_{5/2} Zustands im freien Raum. Wir finden eine Lebensdauer von 1353(5) ns, die mit einer aktuellen theoretischen Vorhersage übereinstimmt. Unsere Messung trägt dazu bei, eine seit langem bestehende Unstimmigkeit zwischen verschiedenen experimentellen und theoretischen Ergebnissen zu beseitigen.Nanophotonic systems are a powerful platform for the study of light-matter interactions. In such systems, the common description of an electromagnetic wave as a wave that is transversely polarized with respect to its propagation direction breaks down. This is due to the tight confinement of the guided light fields, which leads to a longitudinal component of the electromagnetic fields. In this thesis, we use this in conjunction with different coupling strengths of cesium atoms to \sigma^- and \sigma^+ polarized light to provide proof-of-principle demonstrations of novel non-reciprocal optical devices. In the first part of this thesis, we demonstrate non-reciprocal amplification of fiber-guided light using Raman gain provided by spin-polarized cesium atoms that are coupled to the nanofiber waist of a tapered fiber section. We show that our novel mechanism does not require an external magnetic field and that it allows us to fully control the direction of amplification via the atomic spin state. Moreover, we use the chiral light-matter interaction in our system to implement a non-reciprocal antisymmetric optical phase shifter. These results contribute to establishing a new class of spin-controlled, non-reciprocal integrated optical devices and may simplify the construction of complex optical networks. In an additional research project, we also contribute to the fundamental understanding of atoms by precisely measuring the lifetime of an excited cesium state. We measure the lifetime of the cesium 5D_{5/2} state in free space. We find a lifetime of 1353(5) ns, in agreement with a recent theoretical prediction. Our measurement contributes to resolving a long-standing disagreement between several experimental and theoretical results

Advancing stable set problem solutions through quantum annealers

We assess the performance of D-wave quantum solvers for solving the stable set problem in a graph, one of the most studied NP-hard problems. We perform computations on some instances from the literature with up to 125 vertices and compare the quality of the obtained solutions with known optimum solutions. It turns out that the hybrid solver gives very good results, while the Quantum Processing Unit solver shows rather modest performance overall

Intenziviranje procesa gajenja šarana u ruralnim oblastima severnog Vijetnama korišćenjem biljne hrane sa izvorom proteina različitog kvaliteta

U planinskom severnom Vijetnamu, ribnjačka akvakultura je važan deo tradicionalnog integrisanog sistema gajenja koji doprinosi proizvodnji proteina kao i finansijskoj dobiti. Akvakultura u Vijetnamu se najčešće zasniva na polikulturi belog amura sa belim tolstolobikom, sivim tolstolobikom, šaranom i nilskom tilapijom kao sekundarnim vrstama. Ova polikultura se odlikuje niskom produktivnošću od 1.5 t ribe po ha-1 a-1. Glavni razlozi za nizak stepen proizvodnje ribe u ovom region su: korišćenje hrane za ribe niskog kvaliteta (lišće, trava, nusproizvodi gajenja), nepoznata bolest sa visokom stopom smrtnosti belog amura i nekontrolisani protok vode kroz jezera što prouzrokuje zamućenost vode i gubitak mineralnih hranljivih materija za primarnu produkciju. Polu intenzivan system proizvodnje kao i promena načina nasađivanja u kome bi šaran bio najvažnija vrsta u sistemu polikulture može da doprinese većoj produktivnosti i profitabilnosti akvakulture ribnjaka u planinskom delu Vijetnama. Ove promene koje vode ka polu intenzivnoj polikulturi čija je glavna gajena vrsta šaran zahtevaju promenu u izvorima hrane kao i u proizvodnji hrane. Dok je hrana sa visokom energetskom vrednošću naširoko dostupna u region, izvori hrane bogate proteinima su ograničeni. Zbog toga je obavljeno istraživanje da bi se ustanovilo koji su lokalni izvori bogati proteinom najpogodniji da se koriste kao sastojci u dopunskoj ishrani šarana. Obavljena su ispitivanja u mrežnim kavezima u ribnjaku koji je bio nasađen sa tradicionalnim ribljim vrstama, sa gustinom nasada od 1.5 ribe po m2 i šaranom kao glavnom vrstom. Korišćeno je 16 mrežnih kaveza (veličine 2 x 2 x 2 m). Svaki kavez je nasađen sa po 5 primeraka mlađi šarana. Stajnjak preživara kao tradicionalno đubrivo stimulisala je dostupnost prirodne hrane. U tri mrežna kaveza, kao dodatna hrana za šarana korišćene su četiri izo-azotne hranljive smeše pripremljene sa lokalno dostupnim sastojcima sa visokim nivoom proteina (obrok od ribljeg brašna i soje, komercijalni koncentrat hrane za svinje, komercijalna hrana za mlađ ribe i ostaci od soje/tofu) i energije (obrok od kukuruza i obrok od manioke). Dnevna doza iznosila je 3% telesne mase riba. Tri mrežna kaveza nisu dobijala dodatnu hranu. 3 mrezna kaveza nisu dodatno hranjena i sluzila su kao kontrola. Na svakih 20 dana ribe u mrežnim kavezima su merene i količina hrane je usklađivana sa njihovom težinom; šarani iz šesnaestog mrežnog kaveza su izlovljeni radi analize crevinih sadržaja i zatim su ponovo nasađeni. U istom ritmu su praćeni parametri za merenje kvaliteta vode. Na isti način je praćena abundanca zooplanktona i zoobentosa. Uzorci ribe uzeti pre i posle testiranja su analizirani radi ustanovljavanja hemijskog sastava ribe. Hrana je takođe analizirana radi ustanovljavanja hemijskog sastava i sastava amino kiselina. Tradicionalni način đubrenja je stvarao životnu sredinu sa niskom ali vrlo promenljivom dostpupnošću zooplanktona (83 ± 49 mg m-2) i zoobentosa kao hrane (6.5 ± 7.5 mg m-2). Glavni izvor konzumirane prirodne hrane bio je zooplankton čija je veličina tela bila veća od 1mm. Pošto je gustina zooplanktona bila promenjiva, specifična stopa rasta šarana u određenim vremenskim intervalima u različitim tretmanima se mogla porediti sa dostupnošću prirodne hrane. Pozitivna korelacija između dostupne prirodne hrane i performansi rasta utvrđena je u svim slučajevima. Ipak, dostupnost prirodne hrane pod ovim režimom fertilizacije nije bio dovoljan da omogući neto rast šarana bez dodavanja hrane. Dodatno hranjnje je takođe bilo neophodno da bi se održala proizvodnja. Kada je reč o različitim vrstama dodavane hrane, ona bazirana na ostacima soje/tofu je bila najmanje efikasna. Sa ekonomske tačke gledišta, komercijalna hrana za životinje sa visokim nivoom proteina (komercijalna hrana za svinje i ribe) poboljšana lokalno proizvedenim sastojcima pokazala je bolju neto dobit nego hrana u čijem su sastavu kombinovani čisti sastojci (obrok od ribljeg brašna i zagrejane soje) s obzirom da su oni manje prisutni na lokalnom tržištu. Ipak, sva dodatna hrana nije imala dovoljnu količinu i kvalitet proteina da bi sama zadovoljila nivo proteina i esencijalnih amino kiselina koje su potrebne za šarana. Ovi rezultati navode na zaključak da pod dominantnim lokalnim uslovima, dodatna hrana lokalno napravljena od komercijalnih koncentrata hrane za životinja, sastojci bogati energijom mogu da dovedu do povećane proizvodnje ribe ukoliko se kombinuju sa prirodnom hranom koja je stalno dostupna. Ovo će omogućiti da se poveća udeo akvakulture u zaradi kao i u obezbeđenju hrane u domaćinstvima

Stable-Set and Coloring bounds based on 0-1 quadratic optimization

We consider semidefinite relaxations of Stable-Set and Coloring, which are based on quadratic 0-1 optimization. Information about the stability number and the chromatic number is hidden in the objective function. This leads to simplified relaxations which depend mostly on the number of vertices of the graph. We also propose tightenings of the relaxations which are based on the maximal cliques of the underlying graph. Computational results on graphs from the literature show the strong potential of this new approach

Contribution a la connaissance d'une Poussee extraordinaire d' algues unicellulaires (Adriatique Septentrionale)

The phenomenon known as "sea-water bloom" ("mare sporco", "Meeresbliite") was observed in the northern Adriatic in summer 1983. It appears as a gelatinous, dense mass floating at the sea surface. Samples from Crikvenica (July) and Lopar, Rab Island (August) were analysed. A total of 58 diatoms, of which 32 benthic species, 25 dinoflagellates and 10 coccolithophorids were identified by microscopy. A recently described genus, Spatulodinium Cachon & Cachon, represented by the type species S. pseudonoctiluca (Pouchet) Cachon & Cachon, was also found. With respect to the known ecology of individual algal groups it may be concluded that benthic diatoms had reproduced intensively at the sea bottom a long while before the phenomenon became visible at the sea surface. Reproduction is also the period of the most intensive secretion of mucus. Release of the gelatinous mass from the sea bottom at summer temperatures which are unfavourable for diatoms, is actually the end of the bloom. A gelatinous mass full of gases released by bacterial degradation begins to ascend and on its way towards the sea surface, it embeds plankton organisms. In the final stage torn mucus descends to the bottom where it is gradually completely degraded.peer-reviewe

Phonon anomalies and charge dynamics in Fe_{1-x}Cu_{x}Cr_{2}S_{4} single crystals

A detailed investigation of phonon excitations and charge carrier dynamics in single crystals of Fe_{1-x}Cu_{x}Cr_{2}S_{4} (x = 0, 0.2, 0.4, 0.5) has been performed by using infrared spectroscopy. In FeCr_{2}S_{4} the phonon eigenmodes are strongly affected by the onset of magnetic order. Despite enhanced screening effects, a continuous evolution of the phonon excitations can be observed in the doped compounds with x = 0.2 (metallic) and x = 0.4, 0.5 (bad metals), but the effect of magnetic ordering on the phonons is strongly reduced compared to x = 0. The Drude-like charge-carrier contribution to the optical conductivity in the doped samples indicates that the colossal magneto-resistance effect results from the suppression of spin-disorder scattering.Comment: 8 pages, 6 figure

Key influences on motivations for utility cycling (cycling for transport to and from places)

Issue addressed:&nbsp;Although increases in cycling in Brisbane are encouraging, bicycle mode share to work (the proportion of people&nbsp;travelling to work by bicycle) in the state of Queensland remains low. The aim of this qualitative study was to draw upon the lived&nbsp;experiences of Queensland cyclists to understand the main motivators for utility cycling (cycling as a means to get to and from&nbsp;places) and compare motivators between utility cyclists (those who cycle for utility as well as for recreation) and non-utility cyclists&nbsp;(those who cycle only for recreation).Methods: For an online survey, members of a bicycle group (831 utility cyclists and 931 non-utility cyclists, aged 18&ndash;90 years) were&nbsp;asked to describe, unprompted, what would motivate them to engage in utility cycling (more often). Responses were coded into&nbsp;themes within four levels of an ecological model.Results: Within an ecological model, built environment influences on motivation were grouped according to whether they related&nbsp;to appeal (safety), convenience (accessibility) or attractiveness (more amenities) and included adequate infrastructure for short trips,&nbsp;bikeway connectivity, end-of-trip facilities at public locations and easy and safe bicycle access to destinations outside of cities. A key&nbsp;social&ndash;cultural influence related to improved interactions among different road users.Conclusions: The built and social&ndash;cultural environments need to be more supportive of utility cycling before even current utility&nbsp;and non-utility cyclists will be motivated to engage (more often) in utility cycling.So what? Additional government strategies and more and better infrastructure that support utility cycling beyond commuter&nbsp;cycling may encourage a utility cycling culture.</div

Optimizing Phonetic Encoding for Viennese Unit Selection Speech Synthesis

While developing lexical resources for a particular language variety (Viennese), we experimented with a set of 5 different phonetic encodings, termed phone sets, used for unit selection speech synthesis. We started with a very rich phone set based on phonological considerations and covering as much phonetic variability as possible, which was then reduced to smaller sets by applying transformation rules that map or merge phone symbols. The optimal trade-off was found measuring the phone error rates of automatically learnt grapheme-to-phone rules and by a perceptual evaluation of 27 representative synthesized sentences. Further, we describe a method to semi-automatically enlarge the lexical resources for the target language variety using a lexicon base for Standard Austrian German