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Analysis of the recent uptake andimpact of NoSQL databases incompanies : The practices, concept and challenges of NoSQLGullmak, Linnea January 2022 (has links)
Context: Data is at the heart of any information system. Choosing the appropriate database and its operation is a major decision for any company and choosing from the pool of different options can can feel overwhelming. In this thesis we take a look at the main factors to consider when making your decision, to help you with the whole process. This thesis will explore the selection, prioritization and considerations when choosing a database. It is aimed at exploring the recent uptake and impact of NoSQL in companies and analyze the results of the literature and empirical study. Aim and Objectives: Our aim is to investigate the recent uptakeand continued use of NoSQL databases in software development companies. It is imperative to know how companies are choosing to adopt the right technology for their application. The objective is to provide instructions for companies on how to choose the right DB for their needs and what to consider. Method: Interviews are conducted to find out the process/approach that practitioners employ when choosing the database technology. Then an analysis of the considerations and their priority is conducted using a questionnaire. The focus is on the considerations, meaning factors to consider when choosing a database. Results: The result of the interviews show that infrastructure is the most essential consideration when choosing a DB, and the survey questionnaire show that consistency is the most essential consideration. Conclusions: The result suggests that there are several essential considerations when choosing a database. Furthermore, we conclude that the challenges of adopting NoSQL technology may be the following: only provide eventual consistency, which can impact availability and performance, reliability, the challenges of transitioning, keeping track, lacking data integrity, handling of complex queries, and security and privacy risks.
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Effects of Cocaine on Monoamine Uptake as Measured Ex VivoWang, Zhixia, Ordway, Gregory A., Woolverton, William 21 February 2007 (has links)
The increase in extracellular dopamine (DA) following cocaine administration plays a major role in cocaine abuse. In vitro, cocaine binds to DA transporters (DAT) and blocks DA uptake. Moreover, cocaine can increase extracellular DA concentration as measured by in vivo neurochemical methods. The present study examined the effects of cocaine and other drugs on DA, NE and 5-HT uptake using an ex vivo assay. Rats were injected i.v. with saline or drug and sacrificed at various time points after injections. Brains were dissected for regional monoamine uptake studies ex vivo. In most brain regions, cocaine given in vivo blocked monoamine uptake as expected. [ H]DA uptake in nucleus accumbens was inhibited with an ED = 22.3 μmol/kg. Cocaine fully inhibited [ H]NE uptake (ED = 4.58 μmol/kg) in the occipital cortex and partially inhibited [ H]5-HT uptake (33% at 30 μmol/kg) in the midbrain. However, under the same conditions [ H]DA uptake in the striatum was not inhibited after injections of cocaine up to 56 μmol/kg. Although the mechanism for this discrepancy is unclear, DA binding and uptake sites may be distinct and/or there may be regional differences in DA transporters.
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Role of Mu-Opioid Receptors in the Behavioral Effects of the Antidepressant TianeptineHan, Jaena January 2021 (has links)
For over half a century, the monoamine hypothesis has been the dominant theoretical framework guiding depression research and drug development. This hypothesis posits that depression arises from a deficiency in the monoaminergic neurotransmitters serotonin, norepinephrine, and possibly dopamine, and that antidepressants function by increasing extracellular availability of these monoamines in the brain, especially at the synaptic level. It is clear however, that the monoamine hypothesis cannot fully explain either the pathophysiology of depression nor the mechanisms of antidepressant action.
Tianeptine is an atypical antidepressant used in Europe to treat patients who respond poorly to selective serotonin reuptake inhibitors (SSRIs). The recent discovery that tianeptine is a mu opioid receptor (MOR) and delta opioid receptor (DOR) agonist has provided a potential avenue for expanding our understanding of antidepressant treatment beyond the monoamine hypothesis. This dissertation aims to understand the neural circuits underlying tianeptine’s antidepressant effects.
We first characterized the acute and chronic effects of tianeptine on depressive-like and other opioid-related behaviors in mice, and used genetic and pharmacological models to test whether these behavioral effects are mediated by MOR and/or DOR. We found that acute tianeptine administration produced an antidepressant-like reduction in immobility time in the forced swim test, as well as classic opioid-like effects including analgesia, hypophagia, hyperactivity, and conditioned place preference. These behavioral responses to tianeptine are abolished in MOR knockout (KO) mice and in mice that have been pretreated with an MOR antagonist. By contrast, all responses to tianeptine remained intact in DOR KO mice. Remarkably, unlike other classic opiates such as morphine, chronic tianeptine treatment did not produce tolerance to tianeptine’s analgesic effect, nor naloxone-precipitated withdrawal.
The acute behavioral effects of tianeptine (excluding analgesic effects, which were present at 15 minutes, but not 1 hour) were established to occur at 1 hour post-injection and to be largely absent by 3 hours post-injection. Chronically, tianeptine produced an antidepressant effect in corticosterone-treated mice, and prevented the development of restraint-stress-induced depression-like behavior, both in an MOR-dependent manner. Interestingly, tianeptine’s chronic antidepressant-like effects were evident in mice after as little as one week of treatment, rather than several weeks as might be expected for SSRIs.
Using tissue-specific MOR knockouts, we further showed that MOR expression on GABAergic cells, specifically somatostatin-positive neurons, is necessary for the acute and chronic antidepressant-like responses to tianeptine. By contrast, tianeptine’s behavioral effects did not require the expression MORs on D1- and parvalbumin-expressing cells, nor the expression of ß-arrestin 2. These experiments also revealed a dissociation between the antidepressant-like phenotype and other opioid-like phenotypes resulting from acute tianeptine administration such as analgesia, conditioned place preference, and hyperlocomotion.
Critically, we found that tianeptine’s mechanism of action is distinct from fluoxetine in three important aspects: 1) tianeptine requires MORs but not DORs for its chronic antidepressant-like effect, while fluoxetine is the opposite, 2) unlike fluoxetine, tianeptine does not promote hippocampal neurogenesis, and 3) tianeptine’s effects appear to persist even after serotonin depletion.
Taken together, these results suggest a novel entry point for understanding what circuit dysregulations may occur in depression, as well as possible targets for the development of new classes of antidepressant drugs.
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Systolic Blood Pressure Response to Exercise in Relation to Oxygen Uptake in Endurance AthletesEklund, Gustaf January 2021 (has links)
Background: During incremental exercise, systolic blood pressure (SBP) increases due to increasing cardiac output. However, the impact of workload on SBP has often been overlooked. Indexing the increase in SBP to the increase in workload could provide a way of accounting for this. Athletes often reach higher maximal SBP (SBPmax) than untrained subjects, which has been attributed to their superior cardiac capacity. How this affects the relation between SBP and workload is not established. Aim: We sought to characterise the novel metrics SBP/VO2-slope and SBP/Watt-slope in endurance athletes and to analyse possible correlations between these metrics and maximal oxygen uptake (VO2max) in a population of endurance athletes and healthy, non-athletic subjects. We also sought to compare the SBP response of athletes to values predicted by newly published reference equations accounting for workload. Methods: In 24 endurance athletes and 5 healthy non-athletes we assessed the workload-indexed blood pressure response during a graded bicycle ergometer test. SBPmax was defined as the last SBP during exercise, VO2max as the mean of the two highest consecutive VO2 measurements at end of exercise. Results: The mean SBP/VO2-slope was 31.1 ± 9.7 mmHg/l/min and the mean SBP/Watt-slope was 0.28 ± 0.08 mmHg/Watt. We found no significant correlation between VO2max and the SBP/VO2-slope or the SBP/Watt-slope, nor with SBP at 50 W or at 200 W. In males there was a significant correlation between VO2max and SBPmax. The endurance athletes had less steep SBP/Watt-slopes and higher SBPmax than predicted by reference equations. Conclusion: The SBP/VO2-slope offers a precise way of indexing blood pressure to workload and could provide a valuable tool in future studies investigating the SBP response to exercise. Our results suggest that different reference equations than in the general population might be needed when evaluating the SBP response in athletes.
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Synthesis of DMSO based silver nanoparticles for application in wound healingNqakala, Zimkhitha Biancah January 2021 (has links)
>Magister Scientiae - MSc / Silver nanoparticles (AgNPs) apart from being chemically significant, have shown a lot of health benefits, the most studied being their anti-bacterial and anti-inflammatory properties. These biological properties can be further enhanced by adding compounds with known medical properties giving rise to even more desired potent materials. Anti-bacterial and cytotoxicity studies show that these AgNPs can kill bacteria, prevent infections and regenerate skin cells. On the other hand, previous studies have reported dimethyl sulfoxide (DMSO) with attractive wound healing abilities specifically cell growth promotion. It was then envisaged that the combination of DMSO and AgNPs could lead to a potent wound healing agent. It is a well-known fact that non-healing wounds pose a socioeconomic threat to a large population worldwide. / 2023
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Brain Glucose Transporter (Glut3) Haploinsufficiency Does Not Impair Mouse Brain Glucose UptakeStuart, Charles A., Ross, Ian R., Howell, Mary E.A., McCurry, Melanie P., Wood, Thomas G., Ceci, Jeffrey D., Kennel, Stephen J., Wall, Jonathan 12 April 2011 (has links)
Mouse brain expresses three principal glucose transporters. Glut1 is an endothelial marker and is the principal glucose transporter of the blood-brain barrier. Glut3 and Glut6 are expressed in glial cells and neural cells. A mouse line with a null allele for Glut3 has been developed. The Glut3-/- genotype is intrauterine lethal by 7 days post-coitis, but the heterozygous (Glut3+/-) littermate survives, exhibiting rapid post-natal weight gain, but no seizures or other behavioral aberrations. At 12 weeks of age, brain uptake of tail vein-injected 3 H-2-deoxy glucose in Glut3 +/- mice was not different from Glut3+/+ littermates, despite 50% less Glut3 protein expression in the brain. The brain uptake of injected 18F-2-fluoro-2-deoxy glucose was similarly not different from Glut3+/- littermates in the total amount, time course, or brain imaging in the Glut3+/- mice. Glut1 and Glut6 protein expressions evaluated by immunoblots were not affected by the diminished Glut3 expression in the Glut3+/- mice. We conclude that a 50% decrease in Glut3 is not limiting for the uptake of glucose into the mouse brain, since Glut3 haploinsufficiency does not impair brain glucose uptake or utilization.
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Preparation, Characterization, and Use of Antioxidant-LiposomesYang, Hongsong, Paromov, Victor, Smith, Milton, Stone, William L. 01 December 2008 (has links)
Antioxidant liposomes provide a unique means of delivering both water and/or lipid soluble antioxidants to tissues thereby affecting disease states or signal transduction pathways modulated by oxidative stress. Considerable evidence suggests that liposome-encapsulated antioxidants can be superior to the corresponding free antioxidants in this regard. This chapter will provide practical details on the preparation, characterization, and use of antioxidant liposomes. Methods will be described for the small-scale preparation (1 ml) and large-scale (100 ml/hour) preparation of antioxidant liposomes as well as the techniques for characterizing their size distribution and their physical and chemical stability. The use of antioxidant liposomes in an in vitro situation will also be detailed.
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The Interaction Between Water Movement, Solute Uptake, and Respirational Energy in Plant RootsTawakol, Mohamed Sadek 01 May 1967 (has links)
Sunflower plants (Helianthus annus, var. Russian mammoth) were grown in Hogland nutrient solution. The roots (after being subjected to treatments with either respiratory inhibitors or respiratory stimulators) were used to measure the flux of water Jw, flux of solute Js , and the rate of respiration Jo.
The thermodynamic theory of irreversible processes was used to examine the interaction between fluxes, and the changes in conductivity under different treatments. The rate equations for a root membrane of unit thickness were developed as:
Jw = LwwVw∆p + LwsRT ln C1s/C2s +LwoRT ln C1o/C2o
Js = LswVx∆p + LssRT ln C1s/C2s + LsoRT ln C1o/C2o
Jo = LowVw∆p + Los RT ln C1s/C2s + LooRT ln C1o/C2o
Where: Lww, Lss, Loo are the direct transfer coefficients for water, solute , and oxygen; and Lws, Lsw, Lwo, Low, Lso, Los are the interaction or linked transfer coefficients; Vw partial molal volume (or specific volume) of water , ∆p the difference in pressure between the external solution and xylem: C1s and C2s , C1o and C2o are the salt and oxygen concentration in external solution and xylem respectively.
The results showed that: 1. The nonlinearity of the flux of water through the root system of sunflower is due to causes associated with the membrane (mainly the permeability). 2. The increase in respiration did not increase the permeability of the membrane. 3. The uptake of water due to solute potential under transpiring conditions is small, but important. 4. The uptake of solute in normal root systems is by active process fromsolutions to the zylem and then moves passively to the leaves. 5. An increase in passive water uptake might cause an increase of respiration of the root.
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The Inhibition of Water Uptake in Sugar Beet Roots by AmmoniaStuart, Darrel Marshall 01 May 1966 (has links)
Various ammonium salts, urea, aqua ammonia, and anhydrous ammonia are important sources of nitrogen for the fertilization of agricultural crops. While ammonia and its compounds are useful as fertilizers, they can be, and often are, toxic to many plants (Willis and Rankin, 1930; Stout and Tolman, 1941; Raleigh, 1942; Stoll, 1954; Lorenz, 1955; Grogan and Zink, 1956; Allen, 1962; Cooke, 1962; Allred, 1963; Court et al, 1964; Hood and Ensminger, 1964). There are also products which have been designed to retard the oxidation of ammonia and its compounds (Go ring, 1962). It is therefore important that the effects of ammonia and its compounds on plants, plant growth and plant metabolism be fully understood.
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Measuring and Modeling of Plant Root Uptake of Organic ChemicalsDettenmaier, Erik 01 December 2008 (has links)
Determining the root uptake of xenobiotic organic chemicals into plants is critical for assessing the human and ecological health risks associated with the consumption of plants growing in contaminated environments. Root uptake of xenobiotic organics occurs passively in conjunction with transpiration and the transport from root to shoot is ultimately controlled by passage through one or more lipid root membranes. The transpiration stream concentration factor (TSCF), the ratio between the concentration of a chemical in the xylem to that in the solution used by the roots, is used to describe the relative ability of an organic chemical to be passively transported from root to shoot. However, relatively few experimental TSCF values exist due to the cost and the lack of regulatory requirements for generating such data. Where literature data exist for chemicals having more than one TSCF, the variability is often large due to the lack of standardized methods and difficulty in accounting for metabolism and volatilization losses occurring during the uptake experiments. Because of the scarcity of experimental values, estimated TSCFs are often used. Widely cited estimation approaches relating TSCF and the logarithm octanol/water partition coefficient (log KOW) suggest that only compounds that are in the intermediate lipophilicity range (log KOW = 2) will be taken up and translocated by plants. However, recent data for highly water soluble compounds such as 1,4-dioxane, MTBE, and sulfolane suggest that these estimation techniques should be critically reviewed. To re-evaluate the relationship between TSCF and log Kow, TSCFs were measured for 25 organic chemicals ranging in log KOW from -0.8 to 5 using an improved pressure chamber technique. The technique provides an approach for efficiently generating consistent plant uptake data. By using this data, a new mass transfer model relating TSCF and log KOW was developed that indicates that neutral, polar organic compounds are most likely taken up by plant roots and translocated to shoot tissue. An extensive review of literature TSCF studies supports the updated model.
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