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1H NMR spectroscopic elucidation in solution of the kinetics and thermodynamics of spin crossover for an exceptionally robust Fe2+ complexPetzold, Holm, Djomgoue, Paul, Hörner, Gerald, Speck, J. Matthäus, Rüffer, Tobias, Schaarschmidt, Dieter 15 September 2016 (has links)
A series of Fe2+ spin crossover (SCO) complexes [Fe(5/6)]2+ employing hexadentate ligands (5/6) with cis/trans-1,2-diamino cyclohexanes (4) as central building blocks were synthesised. The ligands were obtained by reductive amination of 4 with 2,2′-bipyridyl-6-carbaldehyde or 1,10-phenanthroline-2-carbaldehyde 3. The chelating effect and the rigid structure of the ligands 5/6 lead to exceptionally robust Fe2+ and Zn2+ complexes conserving their structure even in coordinating solvents like dmso at high temperatures. Their solution behavior was investigated using variable temperature (VT) 1H NMR spectroscopy and VT Vis spectroscopy. SCO behavior was found for all Fe2+ complexes in this series centred around and far above room temperature. For the first time we have demonstrated that the thermodynamics as well as kinetics for SCO can be deduced by using VT 1H NMR spectroscopy. An alternative scheme using a linear correction term C1 to model chemical shifts for Fe2+ SCO complexes is presented. The rate constant for the SCO of [Fe(rac-trans-5)]2+ obtained by VT 1H NMR was validated by Laser Flash Photolysis (LFP), with excellent agreement (1/(kHL + kLH) = 33.7/35.8 ns for NMR/LFP). The solvent dependence of the transition temperature T1/2 and the solvatochromism of complex [Fe(rac-trans-5)]2+ were ascribed to hydrogen bond formation of the secondary amine to the solvent. Enantiomerically pure complexes can be prepared starting with R,R- or S,S-1,2-diaminocyclohexane (R,R-trans-4 or S,S-trans-4). The high robustness of the complexes reduces a possible ligand scrambling and allows preparation of quasiracemic crystals of [Zn(R,R-5)][Fe(S,S-5)](ClO4)4·(CH3CN) composed of a 1 : 1 mixture of the Zn and Fe complexes with inverse chirality. / Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Genetické algoritmy – Multi-core CPU implementace / Genetic Algorithms - Multi-core CPU ImplementationStudnička, Vladimír January 2010 (has links)
his diploma thesis deals with creating the most universal library of genetic algorithms in C++, as much as possible, implemented with the certain number of universal operators, and then with testing created library on some examples. Library must support multi-core processors, implementation will be done over OpenMP. The library will be tested on three examples in all. The first two examples are mathematical functions, that are used just for genetic algorithms testing. Last problem for test is N-Queens problem. Finally we will use genetic algorithms to try find solution for Eternity II puzzle, there is declared a 2 million bounty for full solution.
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Direct Ink Write Processing of Signal Crossovers Using Aerosol Jet Printing MethodClark, Lucas A. 18 May 2023 (has links)
No description available.
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Interpretive Phenomenological Analysis: The Lived Experiences of Faculty Who Teach Traumatized Students in Higher EducationBoone, Danielle Marie 15 May 2023 (has links)
No description available.
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A COMPARISON OF HIGHER VERSUS LOWER DIETARY PROTEIN INTAKE ON GLOMERULAR FILTRATION RATE IN HEALTHY ADULTS: A SYSTEMATIC REVIEW AND META-ANALYSIS / AN ANALYSIS OF HIGHER PROTEIN DIETS ON RENAL FUNCTIONSITHAMPARAPILLAI, ARJUN 11 1900 (has links)
Background: Higher protein diets, especially from animal sources, have seen a rise in popularity due to potential metabolic. This may have consequences for kidney function particularly in rising middle class populations who are allocating more income towards meat. The objective of this systematic review and meta-analysis was to evaluate the effects of higher versus lower protein intake on glomerular filtration rate (GFR) in adult populations without renal impairment.
Methods: Search strategies were developed and electronic databases searched: MEDLINE and EMBASE. Data were extracted up until June 3, 2015. The main outcome measure was GFR and a random effect model (Cochrane’s Review Manager Version 5.3) was used to pool mean differences in GFR values.
Results: Database searches yielded 25 trials from 1914 articles that were eligible for analysis based on inclusion/exclusion criteria. 12 studies were randomized controlled trials and 11 studies were crossover trials. As a result of data presented, 2 crossover studies were treated as 4 trials to result in 25 total trials. A total of 810 subjects from 25 trials were included in this systematic review and meta-analyses. The age of participants was 24-62 years and their BMI was 21-36 kg/m2. Higher protein compared to lower protein-containing diets were associated with increased GFR values [mean difference (MD): 8.33 ml/min (95% CI 4.87 to 11.79), P < 0.00001] but this was less pronounced when assessing change from baseline GFR values [MD: 4.71 ml/min (95% CI 0.06 to 9.36), P = 0.05]. Moreover, significant heterogeneity was present and funnel plot asymmetry indicated potential publication bias in both meta-analyses.
Conclusion: Higher protein diets were associated with increased GFR, however, these results were inconclusive due to significant heterogeneity and overestimation by random effect analyses. There is still no clear evidence that high protein diets negatively impact renal function in healthy populations. / Thesis / Master of Science (MSc) / Globally, the leading causes of mortality in industrialized countries are cardiovascular disease (CVD), stroke, and type 2 diabetes (T2D). Deaths from these chronic diseases now outpace deaths due to malnutrition. Being overweight and obese increases the risk of both morbidity and mortality from CVD, stroke, and T2D. Global rates of overweight and obesity have now reached ‘epidemic’ proportions and the World Health Organization has stated that, “… [a] global epidemic of overweight and obesity – ‘globesity’ – is taking over many parts of the world. If immediate action is not taken, millions will suffer from an array of serious health disorders.” Over the past 20-30 years, the popularity of higher protein energy restricted diets have grown due to the potential benefits regarding weight loss, appetite regulation, and maintenance of lean (muscle) mass. Additionally, the expansion of the global ‘middle-class’ has resulted in families allocating more income towards meat products as a primary protein source in their diet. A health concern is that higher protein intake may have an adverse effect on kidney function. In individuals with chronic kidney disease, higher protein diets have been shown to result in further renal impairment. However, the effects of increased protein intake in healthy populations are unclear. The aim of this systematic review and meta-analysis was to compare higher versus lower protein diets on kidney function in healthy populations based on the literature to date. This was accomplished by looking at changes in glomerular filtration rate (the rate at which kidneys filter blood), which is the ‘gold standard’ marker of kidney function.
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A lexical analysis of select unbounded dependency constructions in KoreanLee, Sun-Hee 18 June 2004 (has links)
No description available.
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Experimental Studies on the Mechanical Durability of Proton Exchange MembranesLi, Yongqiang 28 December 2008 (has links)
Three testing methods are proposed to characterize properties of fuel cell materials that affect the mechanical durability of proton exchange membranes (PEMs). The first two methods involved measuring the in-plane biaxial strength of PEMs and the biaxial hygrothermal stresses that occur in PEMs during hygrothermal cycles. The third method investigated the nonuniform thickness and compressibility of gas diffusion media which can lead to concentrated compressive stresses in the PEM in the through-plane direction.
Fatigue and creep to leak tests using multi-cell pressure-loaded blister fixtures were conducted to obtain the lifetimes of PEMs before reaching a threshold value of gas leakage. These tests are believed to be more relevant than quasi-static uniaxial tensile to rupture tests because of the introduction of biaxial cyclic and sustained loading and the use of gas leakage as the failure criterion. They also have advantages over relative humidity cycling test because of the controllable mechanical loading. Nafion® NRE-211 membrane was tested at three different temperatures and the time-temperature superposition principle was used to construct a stress-lifetime master curve. Tested at 90°C, extruded Ion Power® N111-IP membrane was found to have longer lifetime than Gore™-Select® 57 and Nafion NRE-211 membranes under the same blister pressure profiles.
Bimaterial specimens fabricated by bonding a piece of PEM to a substrate material were used to measure the hygral stresses, compressive and tensile, in the PEM during relative humidity cycles. The substrate material and its thickness were carefully chosen so that stresses in the PEM could be obtained directly from the curvature of the bimaterial specimen without knowing the constitutive properties of the PEM. Three commercial PEMs were tested at 80°C by cycling the relative humidity between 90% and 0% and by drying the membrane to 0%RH after submersion in liquid water. Stress histories for all three membranes show strong time-dependencies and Nafion® NRE-211 exhibited the largest tensile stress upon drying.
Besides in-plane stresses, hard spots in gas diffusion media (GDM) can locally overcompress PEMs in the out-of-plane direction and cause electrical shorting. In this study, GDM samples sealed with an impermeable Kapton® film on the surface were compressed with uniform air pressure and the nonuniform displacement field was measured with a three-dimensional digital image correlation technique. Hard spots as a result of the nonuniform thickness and compressibility of the GDM were found and their severities as stress risers are evident. Locally, a nominal platen compression (similar to bipolar plate land compression) of 0.68 MPa can lead to compressive stress as large as 2.30 MPa in various hard spots that are in the order of 100s µm to 1 mm in size. / Ph. D.
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Comparative pilot study of 3D Manufactured and Conventional Manufactured Custom Made Foot Orthotics when looking at Plantar Pressure Distribution and Comfort in adultsMågård-Hansen, Alexander, Sejersen, Camilla Louise January 2024 (has links)
Background 3D manufacturing is a newer technology that shows potential and has gained interest in the world of medical devices. It has been used to produce custom made foot orthotics (CFO)s, but little evidence on the biomechanical effects is available. The literature suggests that the 3D manufactured CFOs (3DMCFO) have comparable outcomes as conventional manufactured CFOs (CMCFO). Purpose The purpose of this pilot study was to investigate biomechanics and comfort in the 3D manufacturing method, because of the lack of biomechanical evidence in literature, and because comfortable orthotics are a prerequisite for an optimal foot orthosis. Methods This pilot project uses a randomized crossover study design to test if there is a difference in plantar pressure distribution and comfort between 3DMCFOs and CMCFOs on two participants (n=2). To investigate the plantar pressure distribution the F-scan® in-shoe sensors was used to measure peak plantar pressures. To evaluate comfort the Orthosis Comfort Score (OCS) was used. Result For both participants similar results of mean peak pressures could be seen in some areas in the two CFOs, where in other areas contradictory results were seen. The comfort in the two CFOs was similar. Conclusion Similarities was seen in plantar pressure distribution and comfort in the two CFOs in both participants. However, the validity and reliability are low because of the low number of participants. / Baggrund 3D print er en nyere produktionsmetode som viser potentiale og har vækket interesse inden for medicinske hjælpemidler. 3D printning er blevet brugt til at producere specialfremstillede fod ortoser (SFO), men der er lav evidens for dens biomekaniske effekt. Litteraturen viser at 3D printede SFOer har sammenlignelige resultater som konventionel produceret SFOer. Formål Formålet med dette projekt var at undersøge biomekanik og komfort for 3D- produktionsmetoden. Dette blev undersøgt fordi der er lidt evidens inden for området, og fordi komfort er en forudsætning for en optimal fod ortose. Metode Dette pilotstudie bruger et randomiseret kontrolleret studie design for at teste om der er en forskel imellem 3D produktionsmetoden og den konventionelle produktionsmetode når der kigges på trykfordeling og komfort i to deltagere (n=2). For at undersøge trykfordeling under foden bruges F- scan® indlæg-sensor, for komfort bruges The Orthosis Comfort Score. Resultat For begge deltagere var der overensstemmelser i de gennemsnitlige høje tryk og i komfort for begge SFOer, hvor der i nogen områder var uoverensstemmelser. Konklusion For de to SFOer, overensstemmelser kunne ses i trykfordelingen under foden og i komfort. Validiteten og pålideligheden for dette projekt er dog ikke højt på grund af det lave deltagerantal.
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Life after Harry / Eine Gattungsdiskussion zeitgenössischer Kinder- und Jugendliteratur in der Post-Potter-Ära / Life After Harry / Contemporary Children’s Literature and Young Adult Fiction in the Post-Potter Era – a Discussion of Genre AspectsFitz, Victoria 03 March 2015 (has links)
No description available.
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Cascades of genetic instability resulting from compromised break-induced replicationVasan, Soumini January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Break-induced replication (BIR) is a mechanism to repair double-strand breaks
(DSBs) that possess only a single end that can find homology in the genome. This situation can result from the collapse of replication forks or telomere erosion. BIR frequently produces various genetic instabilities including mutations, loss of heterozygosity, deletions, duplications, and template switching that can result in copy-number variations (CNVs). An important type of genomic rearrangement specifically linked to BIR is half crossovers (HCs), which result from fusions between parts of recombining chromosomes. Because HC formation produces a fused molecule as well as a broken chromosome fragment, these events could be highly destabilizing. Here I demonstrate that HC formation results from the interruption of BIR caused by a defective replisome or premature onset of mitosis. Additionally, I document the existence of half crossover instability cascades (HCC) that resemble cycles of non-reciprocal translocations (NRTs) previously described in human tumors. I postulate that HCs represent a potent source of genetic destabilization with significant consequences that mimic those observed in human diseases, including cancer.
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