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DARMAN, PAUL STEWART. "THE SYNTHESIS AND BIOLOGICAL EVALUATION OF ALPHA-MELANOTROPIN AND SUBSTANCE P PEPTIDE ANALOGUES (STRUCTURE, FUNCTION)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/187929.
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To investigate the underlying structural features of the neuropeptides α-melanotropin (α-MSH) and substance P (SP), which are responsible for their biological actions, the following study was undertaken. By means of side-chain, fragment and conformational restriction analysis, several α-MSH peptides were prepared by solid-phase synthesis and evaluated by the frog and lizard skin bioassays. Using conformational restriction and fragment methods, several SP peptides were synthesized and examined for biological activity on the guinea-pig isolated ileum, rat brain binding and intrathecal injection assay systems. The results with the new α-MSH analogues show that the histidine-6 side-chain is not needed for signal transduction, but is very important for full potency. The tryptophan-9 side-chain is similarly not needed for signal transduction, but is critically important for full potency. The data also indicate that the positions 6 and 9 side-chains are important for full potency because they likely interact with the melanophore receptor, rather than playing a role in conformationally folding the MSH peptide into a pseudocyclic structure. The results also show that the arginine side-chain at position 8 is not particularly important for signal transduction or full potency, but on the lizard skin bioassay this side-chain is implicated in the previously reported prolongation of Nle⁴, D-Phe⁷-α-MSH. The data provided by the SP peptides suggest that the previously postulated pseudocyclic structure of the 5-11 sequence may not be as fundamental to SP activity as heretofore believed. The data suggest that this type of turn conformation may be important for signal transduction, but is apparently not the only requirement for receptor recognition. Finally, the data show that part of the signal transduction message of SP is contained within the 5-8 region of the peptide, but that most of the receptor recognition elements are probably located outside this sequence.
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Lindsay, Gregory W. "Enhanced Renal Sympathetic and Cardiovascular Responses to Substance P in Hypertension." Digital Commons @ East Tennessee State University, 1993. https://dc.etsu.edu/etd/2718.
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Blood pressure, heart rate, and renal sympathetic nerve responses were measured in 9-13 week old male spontaneously hypertensive rats (SHR) and compared to those in age and sex-matched Wistar-Kyoto (WKY) rats following intravenous injection of the neuropeptide substance P (SP), the nicotinic stimulant 1,1-dimethyl-4-phenylpiperazinium (DMPP), and the adrenoceptor stimulant norepinephrine (NE). Charles River Sprague-Dawley (CD) rats were used in some studies to develop methodologies. Measurements were made in control rats and also following sinoaortic denervation, pithing, ganglion blockade, or adrenoceptor blockade. Responses were evaluated in order to determine if ganglion stimulation by SP was enhanced in SHR compared to WKY rats and if this enhancement was selective for SP or would also be exhibited to DMPP. NE was used to evaluate adrenergic sensitivity and to confirm the success of baroreceptor denervations. SHR exhibited greater intrinsic sympathetic tone than WKY rats before and following ganglion blockade. Ganglion stimulation by SP and DMPP was only fully revealed following elimination of baroreceptor input. Results indicated that SP stimulates sympathetic ganglia to increase renal sympathetic nerve activity, heart rate and blood pressure in CD, SHR and WKY rats. This increase was enhanced in SHR compared to WKY rats in the absence of a similar enhancement of responses to DMPP. The action of SP to cause vasodilation was attenuated in SHR versus WKY rats which may augment its action as a pressor agent in SHR. In conclusion, increases in blood pressure, heart rate and renal sympathetic nerve activity were selectively increased to SP in SHR versus WKY rats. This enhanced action of SP may contribute to the elevation of basal and/or evoked sympathetic discharge observed in this model of hypertension.
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Bondarenko, I. S., О. Г. Аврунін, O. Gryshkov, B. Glasmacher, S. I. Bondarenko, A. V. Krevsun, and M. V. Rakhimova. "Acoustomagnetic detection of magnetic nanoparticles in a model." Thesis, The International Journal of Artificial Organs, 2019. http://openarchive.nure.ua/handle/document/9878.
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Magnetic nanoparticles (MNPs) are used in medicine for targeted drug delivyry to the area of the cancer. The installation consists of the ultrasound generator, the permanent magnet, the glass containerwith the colloidal mixture, the multi-turn coil about of the glass tube and the voltmeter. The experimental result corrilates with the calculated ones. It is suggested that AMM can used to detect MNPs in the real biological substance.
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Landis, Geoffrey Carrothers. "Synthesis and biological activities of tachykinin and opioid-related compounds, synthesis of unusual amino acids, and the investigations into the smooth muscle pharmacology of tachykinins." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184656.
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Eight cyclic analogues of Substance P were made in order to investigate the conformation of the C-terminal end of the peptide. These analogues were designed to test three literature models describing the active conformation of substance P. Although the potencies of the analogues were low (in the micromolar range), our results support Cotrait's and Hospital's model (1986). Several substance P antagonists were synthesized. These compounds did not demonstrate agonistic activity nor anatagonistic activity. The tryptophan side chain is contributing to the antagonistic activity of these analogues, and not just the chirality of the α-carbon. Highly potent and selective photoaffinity ligands of H-Tyr-D-Pen-Gly-Phe-D-Pen-OH (DPDPE) and D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Pen-Thr-NH₂ (CTP) were synthesized. These compounds will be useful in the isolation of δ and μ opioid receptors. Several new amino acids designed and synthesized to contain both the natural amino acid side chain and a thiol group which can be used to make disulfide constraints. The racemic amino acids made were as follows: (1) 2-amino-4-methyl-2- [(p-methylbenzyl)thiomethyl] pentanoic acid; (2) 2-amino-2- [(p-methylbenzyl)thiomethyl] -3-phenylpropanoic acid; (3) 2-amino-e- [(p-methylbenzyl)thio] pentanoic acid; and (4) 2-amino-3- [(p-methylbenzyl)-thio] -3-phenyl-pentanoic acid. These amino acids will be useful in the conformational restriction of peptides. To investigate the δ-opioid receptor conformation proposed for DPDPE by Hruby et al. (1988) and the μ-opioid receptor conformation proposed for Tyr-c [Abu₂,Gly,Phe,Leu] by Mierke et al. (1988), constrained phenylalanine amino acids were incorporated into H-Try-D-Pen-Gly-Phe-D-Pen-OH (DPDPE) in the four position. Our results indicate that these models are correct. And in an investigation into the physical-chemical properties of the delta opioid receptor, our results suggest that the δ receptor topochemical site for the Phe⁴ residue contains a partial positive charge on its surface and has specific steric requirements.
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Plant, Christopher P. "NICOTINE AND METHYLPHENIDATE CHORNIC EXPOSURE ON ADULT CANNABINOID RECEPTOR AGONIST (CP 55,940) PLACE CONDITIONING IN MALE RATS." CSUSB ScholarWorks, 2016. https://scholarworks.lib.csusb.edu/etd/339.
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A problematic connection has been reported between those who use nicotine related products alone or in combination with ADHD medications, like methylphenidate (MPH), in late childhood or early adolescence and the increased likelihood of later marijuana abuse in adulthood. Pre-clinical studies have found that the use of nicotine during the early adolescence period produces enduring changes to the endocannabinoid system in the brain. Since CB agonists, like marijuana, exert their effect through the eCB system, it is possible that early nicotine use may alter the rewarding nature of CB agonists in adulthood. In addition, MPH has also been shown to increase nicotine self-administration and abuse related behaviors of nicotine in rats. Thus, the current study consisted of two experiments looking at the effects of early nicotine and methylphenidate exposure on adult CB-agonist place conditioning in rats. In the first experiment, rats were pre-exposed to either saline or nicotine (0.16, 0.32, or 0.64 mg/kg) from PD 31 to PD 40. On PD 60, rats began a 13-day biased CPP procedure with the CB agonist, CP 55,940 (10, 20 or 30 μg/kg), or vehicle. No significant group differences were found, suggesting that early nicotine exposure does not influence the rewarding nature of CB agonists. Additional individual subgroup comparisons were conducted to determine if any subgroups significantly differed from 0 or no mean change in preference from preconditioning to testing. These analyses revealed that rats pre-exposed to the moderate (0.32 mg/kg) dose of nicotine showed a significant aversion to the high (30 μg/kg) dose of CP 55,940, suggesting that early nicotine exposure may reduce the rewarding nature of CB agonists in adulthood. In the second experiment, rats were pre-exposed to either saline or MPH (0.5, 2, 0r 5 mg/kg) from PD 21 to PD 30. Similar to the first experiment, rats began a 13-day biased CPP procedure on PD 60 with CP 55,940 (10, 20 or 30 μg/kg) or vehicle. Rats conditioned with the moderate (20 μg/kg) dose of CP 55,940 showed a significant preference for the CB agonist as compared to rats conditioned with the high (30 μg/kg) dose of CP 55,940. CP 55,940 exposed rats did not significantly differ from control rats. There was no significant effect of MPH or a MPH x CP 55,940 interaction, suggesting that early MPH exposure does not alter the rewarding nature of CB agonists in adulthood. Together these findings suggest that early nicotine, but not MPH, exposure may influence the rewarding nature of CB agonists in adulthood, suggesting an additional risk factor of early nicotine use. However, future studies should evaluate the effects of persistent nicotine and MPH exposure starting in early adolescence or childhood through adulthood to determine whether the effects of nicotine and MPH are altered if use is continued into adulthood.
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Botros, Milad. "Characterization of Substance P (SP) Aminoterminal SP (1-7) Binding in Brain Regions and Spinal Cord of the Male Rat : Studies on the Interaction with Opioid Related Pathways." Doctoral thesis, Uppsala universitet, Avdelningen för biologisk beroendeforskning, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9401.
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Binding sites for substance P(1-7), SP(1-7) have been identified and characterized for the first time in crude membrane fraction from rat CNS using tritiated ([3H]) SP(1-7) as tracer. These putative receptors were investigated in relation to their affinity for tachykinins, opioid peptides and sigma receptor ligands. [3H]-SP(1-7) specifically binds to high affinity binding sites identified as receptor targets for the heptapeptide SP (1-7). Two distinct binding sites were observed in the spinal cord. One site is recognized by high affinity for SP(1-7) with a Kd of 0.5 nM, whereas the other site showed low affinity for the heptapeptide (Kd=12 nM). In the brain, the binding of SP(1-7) fitted a single site binding model with a Kd of 4.4 nM and a Ki of 4.2 nM. Further, using the spinal cord membranes the binding of [3H]-SP (1-7) was weakly displaced by SP and other N-terminal fragments thereof and no or negligible affinity was observed for ligands of the NK-1, NK-2 and NK-3 tachykinin receptors, C-terminal SP(5-11), Tyr-w-MIF-1 or the mu-opioid receptor antagonists naloxone and naloxonazine. On the other hand it was significantly displaced by endomorphin-2, DAMGO, and Try-MIF-1 and exhibit some affinity for MIF-1, ß-casomorphin and endomorphin-1. However, only endomorphin-2, DAMGO and Tyr-MIF-1 showed affinity in the close range of the native peptide SP(1-7). The affinity of endomorphin-2 for the spinal cord site was 10 times lower than that of SP(1-7) but more than 100 times higher than the affinity recorded for endomorphin-1. Tyr-MIF-1 but not Tyr-w-MIF-1 showed similar affinity as endomorphin-2 for SP(1-7) site. All peptides exhibiting high affinity at the SP(1-7) site, have a phenylalanine or a leucine residue in their C-terminal structure. Further, synthetic analogues of SP(1-7) were tested for their affinity for the SP(1-7) receptor in the rat spinal cord. An important finding here was that the receptor-ligand-interaction was favoured by the C-terminal region of SP(1-7). Residues at positions 5-7 appeared crucial for binding to the specific SP(1-7) site. The presence of the amidated Phe7 residue was extremely critical for binding to the SP(1-7) site.The analogue Gln5-Gln6-Phe7-NH2 was almost equipotent with the parent peptide in the SP (1-7) receptor binding assay. Furthermore, the SP(1-7)-amide potently and dose dependently reduced several signs of the reaction to morphine withdrawal and was significantly attenuated by the addition of the sigma agonist SK-10047. In conclusion, the work presented in this thesis has contributed the characterization of the properties of highly selective binding sites for SP(1-7) in the rat spinal cord and VTA. These sites appear to be distinct from the µ-opioid receptor or any of the known neurokinin receptors. The study further indicates that the SP(1-7)-amide mimics the effect of the nativ heptapeptide and that the mechanisms for its action involve a sigma receptor site.
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Ploux, Olivier. "Synthèse d'analogues cycliques de la substance P : études biochimiques et structurales." Paris 6, 1986. http://www.theses.fr/1986PA066076.
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Shamgochian, Maureen. "The Stimulation of Luteinizing Hormone Secretion from Anterior Pituitary Cells in Culture by Substance P: A Dissertation." eScholarship@UMMS, 1990. https://escholarship.umassmed.edu/gsbs_diss/129.
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The observations that substance P (SP) is localized in the anterior pituitary gland (AP) and is regulated by the hormonal status of the animal, as well as the demonstration of SP binding sites in the AP, have led to the idea that SP may participate in the regulation of AP function. Numerous and sometimes contradictory reports of SP effects on AP hormone secretion, particularly on luteinizing hormone (LH), left the question of whether SP acts directly at the level of the AP to regulate LH secretion still unanswered. To investigate a possible physiological function of SP in the AP, the effects of exogenous SP on LH secretion from AP cells from adult and prepubertal male and female rats in short term culture were studied. It was found that SP (100nM-1μM) significantly stimulates LH release in cultured AP cells and that this effect varies as a function of age and sex. SP has no significant effect on LH release from AP cells of male and female prepubertal rats. After day 30 a sharp increase in the response to SP occurs in both sexes. This level of responsiveness continues through adulthood in AP cells from the female rat. In contrast, AP cells from male rats failed to respond during adulthood (over 50 days of age) but were highly responsive during the peripubertal period (30-35 days). The possibility that the responsiveness to SP is influenced by the endocrine status of the animal was investigated by exposing AP cells from responding animals to androgens in vivo and in vitro. It was found that AP cells from female rats treated with androgen were less responsive to 100nM SP but did respond at higher doses of SP. SP effects on AP function were further analyzed in experiments using radioligand binding assays to assess possible changes in SP receptor number or affinity as related to age and sex. In AP membranes from female rats, maximum binding is 8-fold higher (Bmax=4.2 pmo1/mg membrane protein) than in AP membranes from male rats (Bmax=560fmo1/ mg membrane protein). These studies suggest a role for SP as a secondary regulator of LH secretion with possible physiological significance for reproductive function.
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Skog, Manfred. "Kvantifiering av näringsflöden i Recirkulerande Akvakultur (RAS) och nätkasseodling av lax (Salmo salar)." Thesis, Linköpings universitet, Biologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-149624.
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Aquaculture has been a way to produce fish as a protein source for thousands of years and over the past decades aquaculture has been the fastest expanding animal-based food sector in the world. This study focused on quantifying the flows of nitrogen and phosphorus in Atlantic Salmon farming and compared traditional open net farming with a more recent technique, land based recirculating aquaculture system (RAS). The aim was to quantify the difference in emissions of nitrogen and phosphorus between the two types of farming and to quantify the amount of nutrients that could be reused from the respective fish farm. Data were obtained from reports, scientific publications and an application for environmental permit (EIA) for the case Smögenlax Aquaculture AB. The same feed input and salmon output were assumed in the two systems and a substance flow analysis was used to quantify the flows of nutrients. The amount of produced salmon and fish feed/year were taken from Smögenlax Aquacultures EIA. The results showed that a RAS-based Salmon farm emits only 6 % of the nitrogen and 5 % of the phosphorus emitted to the recipient waters in comparison to an open net farm. RAS-based salmon farming also enables the reuse of 19 % more nitrogen and 47 % more phosphorus than an open net farm by using sludge and fish offal from the farm to create biogas and biofertilizers. RAS is still evolving to provide possibilities for large scale salmon farms on land to be both cost and environmental efficient and may in the future be the most common way to farm Atlantic Salmon.
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Sherwood, Alexander M. "Design, Synthesis and Biological Evaluation of Novel Compounds with CNS-Activity Targeting Cannabinoid and Biogenic Amine Receptors." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1831.
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This work seeks to contribute to the discipline of neuropharmacology by way of structure activity relationship from the standpoint of an organic chemist. More specifically, we sought to develop robust synthetic methodology able to efficiently produce an array of compounds for the purpose of systematic evaluation of their interaction with specific sights within the central nervous system (CNS) in order to better understand the mind and to develop drugs that may have beneficial effects on neurological function.
The focus of these studies has been toward the development of novel molecules, using a structure-activity relationship approach, that exhibit binding affinity at specific targets within the CNS. The merit of such studies is twofold: primarily, new compounds are produced that provide valuable scientific insight about their physiological targets, and secondarily, new synthetic methodologies that may arise in order to produce these compounds, thereby contributing to the whole of organic chemistry.
As a result of the research described herein, the development of one high affinity and several moderate affinity compounds at the cannabinoid receptor subtype 1 (CB1) has been accomplished. The research demonstrates that a diaryl ether molecular scaffold represents a successful motif in the cannabinoid pharmacophore. The production of the compounds in the SAR studies also introduced a novel general synthetic methodology for the synthesis of diaryl ethers around a phloroglucinol core.
A second project was initiated in order to explore the synthetic methods required to develop a general process for the synthesis of rigid aminobenzocyclobutane analogs of known phenethylamines with activity at monoaminergic neurotransmitter sites. Using the synthetic approach devised here, four novel aminobenzocyclobutane isomeric analogs of a known pharmacologically active phenethylamine, (RS)-phenylpropan-amine were synthesized and are currently being evaluated for pharmacological potential.
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Strickland, Justin Charles. "EXAMINING THE UTILITY OF BEHAVIORAL ECONOMIC DEMAND IN ADDICTION SCIENCE." UKnowledge, 2019. https://uknowledge.uky.edu/psychology_etds/154.
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The marriage of perspectives from behavioral economic theory and learning theory has the potential to advance an understanding of substance use and substance use disorder. Behavioral economic demand is a central concept to this interdisciplinary approach. Evaluating demand in the laboratory and clinic can improve previous research on the relative reinforcing effects of drugs by accounting for the multi-dimensional nature of reinforcement rather than viewing reinforcement as a unitary construct. Recent advances in the commodity purchase task methodology have further simplified the measurement of demand values in human participants. This dissertation project presents a programmatic series of studies designed to demonstrate the utility of using a behavioral economic demand framework and the purchase task methodology for understanding substance use disorder through basic and applied science research. Experiments are presented spanning a continuum from theoretical and methodological development to longitudinal work and clinical application. These experiments demonstrate three key conclusions regarding behavioral economic demand. First, behavioral economic demand provides a reliable and valid measure of drug valuation that is applicable to varied drug types and participant populations. Second, behavioral economic demand is a stimulus-selective measure specifically reflecting valuation for the commodity under study. Third, behavioral economic demand provides incremental information about substance use in the laboratory and clinical setting above and beyond traditional measures of reinforcer valuation and other behavioral economic variables. These findings collectively highlight the benefits of behavioral economic demand and provide an important platform for future work in addiction science.
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Hallberg, Mathias. "Anabolic Androgenic Steroids : Effects on Neuropeptide Systems in the Rat Brain." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5745.
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Batten, Seth Richard. "MEASURING GLUTAMATE AND OXYGEN IN BRAIN REWARD CIRCUITS IN ANIMAL MODELS OF COCAINE ABUSE AND DECISION-MAKING." UKnowledge, 2019. https://uknowledge.uky.edu/psychology_etds/165.
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Drug-specific reward and associated effects on neural signaling are often studied between subjects, where one group self-administers drug and a separate group self-administers a natural reinforcer. However, exposure to drugs of abuse can cause long-term neural adaptations that can affect how an organism responds to drug reward, natural reward, and their reward-associated stimuli. Thus, to isolate drug-specific effects it is important to use models that expose the same organism to all of the aforementioned. Multiple schedules provide a means of dissociating the rewarding effects of a drug from the rewarding effects of food within a single animal. Further, drug users do not take drugs in isolation; rather, they are often faced with several concurrently available commodities (e.g. monetary goods, social relationships). Thus, using choice measures to assess the relative subjective value of drug reinforcers in both humans and animals promotes a translational understanding of mechanisms that govern drug-associated decision-making. Thus, in order to gain a more translational view of the neurobehavioral mechanisms that underlie drug-associated behavior, in the first study, glutamate was measured in the nucleus accumbens core (NAcC) and prefrontal cortex (PrL) in freely-moving rats as they behaved in a cocaine-food multiple schedule procedure. In the second study, oxygen dynamics were measured in the orbitofrontal cortex (OFC) of freely-moving rats as they behaved in a cocaine/food choice procedure. The results from the first study showed that, in the NAc and PrL, there was an increase in glutamate release when animals earned cocaine. Further, the number of glutamate peaks that occurred per cocaine lever press and per cocaine reinforcer was increased compared to food. In the second study, OFC oxygen dynamics were positively correlated with cocaine/food choice and generally tracked preference. Further, OFC oxygen dynamics were greater to cocaine related events. Taken together, these results showed the feasibility of combining electrochemical measurements with complex drug-related behavioral procedures. These results also highlight the importance of the PrL, NAcC, and OFC in the valuation of drug and non-drug commodities. Overall, these results add to our understanding of the neurobehavioral mechanisms that guide drug-associated behavior and create more precise experimental avenues to research potential treatments.
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REYDAMS, Louise Hallal. "Substâncias psicoativas e ritmo biológico em uma amostra comunitária de jovens." Universidade Catolica de Pelotas, 2018. http://tede.ucpel.edu.br:8080/jspui/handle/jspui/728.
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Substance use disorder is related to numerous mental and physical health problems, associated with several functional impairments that affect several aspects of the life of the individual with the disorder. The objective of this study was to evaluate the relationship between psychoactive substances and biological rhythm in a community sample of young people. It is a cross-sectional population-based study with adults aged 24 to 30 years living in the urban area of the city of Pelotas, RS. The sample selection was performed by multi-stage conglomerates. Socio-demographic data were collected from the sample and substance abuse or dependence was assessed through the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), as well as the biological rhythm was evaluated through the Biological Rhythm Interview of Assessment Neuropsychiatry (BRIAN). A total of 1241 subjects were evaluated. The prevalence of substance use disorders in the sample was as follows: alcohol 14.1% (n=175), tobacco 30.8% (n=382), cannabis 10.5% (n=130), cocaine/crack 8.4% (n=104) and other psychoactive substance use disorder 9.2% (n=114). In the model of linear regression adjustment, alcohol use disorder was able to predict change in sleep/social pattern (p<0.001), activity (p=0.024), eating pattern (p=0.049) and overall rhythm (p<0.001). Other psychoactive substance use disorder was also predictive of changes in the sleep/social pattern (p <0.001), activity (p<0.001), eating pattern (p<0.001) and overall rhythm (p<0.001). Our findings suggest that individuals with alcohol and other psychoactive use disorders presented greater changes in sleep/social patterns, activity and food patterns, as well as greater disruptions in maintaining the overall biological rhythm.
O transtorno por uso de substâncias está relacionado a inúmeros problemas de saúde mental e física, associado a diversos prejuízos funcionais que afetam diversos aspectos da vida do indivíduo portador do transtorno. O objetivo deste estudo foi avaliar a relação entre substâncias psicoativas e ritmo biológico em uma amostra comunitária de jovens. Trata-se de um estudo transversal de base populacional com adultos de 24 a 30 anos de idade residentes da zona urbana da cidade de Pelotas-RS. A seleção amostral foi realizada por conglomerados com múltiplos estágios. Foram coletados dados sócio-demográfico da amostra e o abuso ou dependência de substâncias foi avaliado através do Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), bem como o ritmo biológico foi avaliado através da Biological Rhythm Interview of Assessment Neuropsychiatry (BRIAN). Foram avaliados 1241 sujeitos. As prevalências de transtornos por uso de substâncias na amostra foram as seguintes: álcool 14,1% (n=175), tabaco 30,8% (n=382), cannabis 10,5% (n=130), cocaína/crack 8,4% (n=104) e uso de outra substância psicoativas 9,2% (n=114). No modelo de ajuste por Regressão Linear, transtorno por uso de álcool foi capaz de predizer mudança no padrão de sono/social (p<0,001), atividade (p=0,024), alimentação (p=0,049) e ritmo global (p<0,001). Além disso, o transtorno por uso de outras substâncias psicoativas também foi capaz de predizer mudanças no padrão de sono/social (p<0,001), atividade (p<0,001), alimentação (p<0,001) e ritmo global (p<0,001). Nossos sugerem que os indivíduos com transtorno por uso de álcool e outras substâncias psicoativas apresentaram maiores alterações no padrão de sono/social, na atividade e no padrão alimentar, bem como, apresentaram maiores disrupturas na manutenção do ritmo biológico global.
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Zhao, Renzun. "Management strategy of landfill leachate and landfill gas condensate." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77186.
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Studies were conducted to evaluate the impact of landfill leachate discharge on the operation of waste water treatment plants (WWTPs). Two aspects of interferences were found: one is UV quenching substances, which are bio-refractory and able to penetrate the biological treatment processes, consequently interfere the UV disinfection in WWTPs. The other one is organic nitrogen, which can pass the nitrification-denitrification process and contribute to the effluent total nitrogen (TN). Also, treatability study was conducted for landfill gas (LFG) condensate. In a laboratory study, leachate samples were fractionated into humic acids (HA), fulvic acids (FA) and Hydrophilic (Hpi) fractions, the specific UV254 absorbance (SUVA254) of the three fractions follows: HA > FA > Hpi. However, the overall UV254 absorbance of the Hpi fraction was important because there was more hydrophilic organic matter than humic or fulvic acids. It was found that the size distribution of the three fractions follows: HA > FA > Hpi. This indicates that membrane separation following biological treatment is a promising technology for the removal of humic substances from landfill leachates. Leachate samples treated in this manner could usually meet the UV transmittance requirement of the POTWs. Also, nitrogen species in landfill leachates under various stabilization states were investigated. Although the effect of landfill stabilization state on the characteristics of organic matter and ammonia is well documented, there are few investigations into the landfill leachate organic nitrogen under different stabilization stages. Ammonia was found to leach out slower than organic matter and can maintain a constant level within the first a couple of years (< 10 years). The concentration and biodegradability of organic nitrogen were found to decrease with landfill age. A size distribution study showed that most of organic nitrogen in landfill leachates is < 1 kDa. The protein concentration was analyzed and showed a strong correlation with the organic nitrogen. Different slopes of regression curves of untreated and treated leachates indicate that protein is more biodegradable than the other organic nitrogen species in landfill leachates. XAD-8 resin was employed to isolate the hydrophilic fraction of leachate samples, hydrophilic organic nitrogen was found to be more biodegradable/bioavailable than the hydrophobic fractions. Furthermore, biological and physical-chemical treatment methods were applied to a landfill biogas (LFG) condensate to explore the feasible treatment alternatives for organic contaminant and arsenic removal efficiency. Sequencing batch reactor (SBR) showed effectiveness for the degradation of organic matter, even in an environment containing high levels of arsenic. This indicated a relatively low toxicity of organic arsenic as compared to inorganic arsenic. However, for arsenic removal, oxidation-coagulation, including biological oxidation, conventional oxidation and advanced oxidation followed by ferric salt coagulation, and carbon adsorption were not effective for what is believed to be tri-methyl arsenic. Among these, advanced oxidation-coagulation showed the best treatment efficiency (15.1% removal). Only reverse osmosis (RO) could reduce the arsenic concentration to an acceptable level to meet discharge limits. These results implied high stability and low toxicity of organic arsenic.Ph. D.
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Al-Chalabi, F. T. "Biological interactions between growth regulating substances and herbicides in weed control." Thesis, Bangor University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233243.
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Nisbet, Lorna A. "The analysis and detection of new psychoactive substances in biological matrices." Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/7213/.
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New psychoactive substances (NPSs) have appeared on the recreational drug market at an unprecedented rate in recent years. Many are not new drugs but failed products of the pharmaceutical industry. The speed and variety of drugs entering the market poses a new complex challenge for the forensic toxicology community. The detection of these substances in biological matrices can be difficult as the exact compounds of interest may not be known. Many NPS are sold under the same brand name and therefore users themselves may not know what substances they have ingested. The majority of analytical methods for the detection of NPSs tend to focus on a specific class of compounds rather than a wide variety. In response to this, a robust and sensitive method was developed for the analysis of various NPS by solid phase extraction (SPE) with gas chromatography mass spectrometry (GCMS). Sample preparation and derivatisation were optimised testing a range of SPE cartridges and derivatising agents, as well as derivatisation incubation time and temperature. The final gas chromatography mass spectrometry method was validated in accordance with SWGTOX 2013 guidelines over a wide concentration range for both blood and urine for 23 and 25 analytes respectively. This included the validation of 8 NBOMe compounds in blood and 10 NBOMe compounds in urine. This GC-MS method was then applied to 8 authentic samples with concentrations compared to those originally identified by NMS laboratories. The rapid influx of NPSs has resulted in the re-analysis of samples and thus, the stability of these substances is crucial information. The stability of mephedrone was investigated, examining the effect that storage temperatures and preservatives had on analyte stability daily for 1 week and then weekly for 10 weeks. Several laboratories identified NPSs use through the cross-reactivity of these substances with existing screening protocols such as ELISA. The application of Immunalysis ketamine, methamphetamine and amphetamine ELISA kits for the detection of NPS was evaluated. The aim of this work was to determine if any cross-reactivity from NPS substances was observed, and to determine whether these existing kits would identify NPS use within biological samples. The cross- reactivity of methoxetamine, 3-MeO-PCE and 3-MeO-PCP for different commercially point of care test (POCT) was also assessed for urine. One of the newest groups of compounds to appear on the NPS market is the NBOMe series. These drugs pose a serious threat to public health due to their high potency, with fatalities already reported in the literature. These compounds are falsely marketed as LSD which increases the chance of adverse effects due to the potency differences between these 2 substances. A liquid chromatography tandem mass spectrometry (LC-MS/MS) method was validated in accordance with SWGTOX 2013 guidelines for the detection for 25B, 25C and 25I-NBOMe in urine and hair. Long-Evans rats were administered 25B-, 25C- and 25I-NBOMe at doses ranging from 30-300 µg/kg over a period of 10 days. Tail flick tests were then carried out on the rats in order to determine whether any analgesic effects were observed as a result of dosing. Rats were also shaved prior to their first dose and reshaved after the 10-day period. Hair was separated by colour (black and white) and analysed using the validated LC-MS/MS method, assessing the impact hair colour has on the incorporation of these drugs. Urine was collected from the rats, analysed using the validated LC-MS/MS method and screened for potential metabolites using both LC-MS/MS and quadrupole time of flight (QToF) instrumentation.
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Arunotayanun, W. "Chemical and biological studies on natural and synthetic Novel Psychoactive Substances." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1432658/.
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Over the past decade, the availability of novel psychoactive substances (NPS), so called “legal highs”, has been increasing dramatically worldwide. Natural products (NP) and synthetic compounds based on NP are amongst the most commonly offered by online vendors. Most synthetic substances have recently been introduced and very little is known about their chemical and biological properties. In this project, 18 novel synthetic NPS were selected and purchased online. The full chemical characterizations using NMR, ESI-MS, HRMS, IR and UV techniques as well as in vitro neurological assays were carried out. The chemical analysis of these compounds provided a complete set of fundamental information for future analytical, forensic and synthetic work whereas the neurological results from this study made several noteworthy contributions on pharmacological and toxicological studies. One of the most valuable findings to emerge from this study is that some substances of interest including STS-135, QUPIC, 5F-QUPIC, QUCHIC, AMT, 5-MeO-DALT, 5-EAPB, 3,4-CTMP and 4-MeO-PCP, were found to exhibit moderate to high affinity interactions to at least one neurotransmitter and receptor associated with psychoactive activity suggesting that these products had a powerful potential to generate psychedelic effects in users. Moreover, some of these substances namely 5-MeO-DALT, 5-EAPB, 3,4-CTMP, 5-MAPB and MTTA, could lead to serious adverse reactions in users as they showed appreciable affinity to the 5-HT2B receptor which is known to be associated with valvular heart diseases after long term use. Another striking finding from this study was the antibacterial activities of three related isomers isolated from a commercial sample of LY-2183240, an NPS in the cannabinoid class. A 2,5-regioisomer of LY-2183240 and a novel compound, the 5,1 isomer of LY-2183240, exhibited remarkable antibacterial activities while LY-2183240 (1,5-regioisomer) was found to possess fair activity against the tested S. aureus strains, despite the fact that the structures of these three compounds were closely related. Appreciable activities were also observed for MTTA against S. aureus, as well as 5-MeO-DALT against E. coli. For natural product NPS, whilst some are well-known, without any regulation, these materials are often of dubious identity or are adulterated with other psychoactive plants or compounds, which could cause serious harm to users. Therefore, in this research, a metabolomic approach combined with multivariate data analysis was applied to examine all the metabolites present in the four top natural product NPS (Kratom, Cacti, Fly Agaric, and Hawaiian Baby Woodrose) from various UK websites. The sample preparation, data bucketing and data analysis were developed and 1H-NMR spectroscopy was selected as a tool for sample analysis due to several advantages over other methods. An interesting finding to emerge from this study was the detection of two adulterants in the kratom sample, which were identified by a metabolomic study to possess a distinct metabolite profile compared to the rest of the kratom products. These adulterants were isolated and confirmed as oxoglaucine and glaucine which have recently been classified as NPS. This clearly suggested the practical application of 1H-NMR metabolomic technique as a rapid and efficient analytical tool to produce a valuable database for the quality control of natural product NPS and for the identification of adulterants in the future.
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Magnusson, Kristina. "The Impact of Nandrolone Decanoate on Neuropeptidergic Mechanisms Related to Cognition, Aggression, Reward and Dependence." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-107483.
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Östlund, Eva. "Growth factors and vasoactive substances in intrauterine growth restriction and preeclampsia /." Stockholm, 2001. http://diss.kib.ki.se/2001/91-628-5046-6/.
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Karlsson, Frida. "Estrogenic Substances in Plastic Bottles." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-37117.
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We live in a time were plastic and plastic products are all around us, taking part in our everyday life. Several chemical additives can be present in plastic products, such as plastic bottles, and can have a big impact on development, as well as on the endocrine system in adults by the binding to, and disturbance of, the estrogen receptor (ER) in cells. This study has focused on a number of different plastic bottles made from different types of plastic and with variations in size and scope of use. The aim of the study was to see if any estrogenic substances leached from the bottles into water. Non-ionic water was added to the plastic bottles, and the bottles were kept at 70°C for 72 hours. The estrogenic activity in the water was determined with the U2OS-luc assay and expressed as bioassay-derived estradiol equivalents (Bio-EEQ). A difference in Bio-EEQ could be detected between the bottles and the tree plastic types used in the study. The polypropylene (PP) bottle gave the highest Bio-EEQ of 0.5 pg/ml, whereas High Density Polyethylene (HDPE) gave 0.3 pg/ml and Polyethylene Terephthalate (PET) 0.04 pg/ml. These results indicate that there is a small leakage of estrogenic substances from the plastic bottles. Further study is needed to determine whether or not the estrogenic activity in the water could have any significant biological effect in humans.Vi lever i en tid där plast och plastprodukter finns överallt runt omkring oss och har en stor del i vår vardag. Många kemiska ämnen kan återfinnas i plastprodukter, såsom plastflaskor, och kan ha en stor inverkan inte bara på den växande kroppen hos barn utan även ge endokrina störningar hos vuxna människor. Detta kan till exempel ske genom att ämnen kan binda till och påverka östrogenreceptorn (ER) i cellerna. Den här studien fokuserar på plastflaskor gjorda av olika typer av plast och med varierande storlek och användningsområde. Syftet med studien var att se huruvida några östrogena substanser kunde lakas ut i vatten som förvarades i flaskorna. Flaskorna fylldes med avjoniserat vatten och förvarades i 70°C i 72 timmar. Östrogenaktiviteten i vattnet mättes sedan i en cellbaserad testmetod, kallad U2OS-luc assay, där den samlade biologiska effekten av alla östrogena ämnen kan mätas. Effekten uttrycks som bioassay-derived estradiol equivalents (Bio-EEQ). Vatten från polypropenflaskan (PP) gav det högsta Bio-EEQ på 0,5 pg/ml medan högdensitetspolyeten (HDPE) gav 0,3 pg/ml och polyetylentereftalat (PET) ett Bio-EEQ på 0,04 pg/ml. Dessa resultat indikerar att plastflaskorna läcker ut små mängder östrogenlika ämnen. Vidare studier behöver göras för att avgöra huruvida detta läckage utgör någon risk för människor.
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Villafranca, Steven Wayne. "The effect of early psychostimulant treatment on abuse liability and dopamine receptors." CSUSB ScholarWorks, 2005. https://scholarworks.lib.csusb.edu/etd-project/2824.
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Examines whether the reinforcing properties of drugs of abuse were altered in adulthood by methylphenidate, more commonly known as Ritalin. Subjects were 108 rats of Sprague-Dawley descent (Harlan). Methylphenidate, or saline was administered daily to the subjects from the postnatal period (11-20 days old). The rats preference for morphine during early adulthood was measured using conditioned place preference. The number of dopamine D₂ receptors was measured in each rat and the correlation between receptor number and morphine preference was determined. Results indicate that rats pretreated with methylphenidate showed greater preference for morphine than saline pretreated rats and suggests that exposure to methylphenidate during the postnatal period increases the rewarding value of morphine.
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Sifi, Bouaziz. "Valorisation des écorces de chêne (quercus pedunculata) et de leurs substances hydrosolubles." Nancy 1, 1987. http://www.theses.fr/1987NAN10108.
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Influence de la maturité du compost d'écorce de chêne et des extraits d'écorce sur l'aptitude à servir de substrat pour la culture de végétaux supérieurs (tomates). Aspects ultrastructuraux et effets sur la germination et la croissance (inhibition, stimulation)
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Esaka, Yukihiro. "DEVELOPMENT OF SEPARATION METHODS FOR BIOLOGICAL SUBSTANCES BY CAPILLARY ELECTROPHORESIS AND LIQUID CHROMATOGRAPHY." Kyoto University, 1995. http://hdl.handle.net/2433/78069.
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Mignogna, Kristin. "Genome-Wide Systems Genetics of Alcohol Consumption and Dependence." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5946.
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Widely effective treatment for alcohol use disorder is not yet available, because the exact biological mechanisms that underlie this disorder are not completely understood. One way to gain a better understanding of these mechanisms is to examine the genetic frameworks that contribute to the risk for developing this disorder. This dissertation examines genetic association data in combination with gene expression networks in the brain to identify functional groups of genes associated with alcohol consumption and dependence.
The first study took advantage of the behavioral complexity of human samples, and experimental capabilities provided by mouse models, by co-analyzing gene expression networks in the mesolimbocortical system of acute alcohol-treated mice and human genetic alcohol dependence association data. This study successfully identified ethanol-responsive gene expression networks with overrepresentation of genes suggestively associated with alcohol dependence in an independent human sample, indicating that gene expression networks in mouse models are informative for identifying mechanistic networks relevant to the risk for developing dependence.
The second study aimed to identify quantitative trait loci for voluntary alcohol drinking behaviors under an intermittent ethanol access paradigm, in the genetically complex Diversity Outbred mice. After determining high heritability for alcohol consumption and dependence amongst the progenitor strains, we identified several specific genetic loci associated with these traits. One locus replicated results from a human association study of alcohol consumption, and provided insight to the potentially contributing genes. Finally, we identified alcohol consumption-correlated gene expression networks in the prefrontal cortex of these mice. We also mapped quantitative trait loci for network expression levels, some of which overlapped with the behavioral loci, indicating that the functions represented by these modules mediate the relationship between the genotypes in that region and drinking behaviors. Overall, our studies revealed neuroplastic and ubiquitin-related genes pathways involved in alcohol consumption in mice and humans, and that likely contribute to the risk for developing dependence.
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Beard, Daniel A. "Advection and diffusion of substances in tissues containing complex vascular networks /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/8015.
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Hale, Kerry Anne. "The formation, synthesis and reactions of humic polymers in chemical and biological systems." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329937.
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Short, Douglas Mackay. "Chemical mechanisms underlying some biological reactions mediating the cytotoxicity and therapeutic potential of nitric oxide." Thesis, University of St Andrews, 1999. http://hdl.handle.net/10023/14102.
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Some in vitro reactions of peroxynitrite are examined using 15N CIDNP NMR spectroscopy to elucidate more information about the radical nature of nitration, nitrosation and isomerisation mechanisms. Preliminary work on the nitration of tyrosine with H15NO3 confirms that 3-nitrotyrosine forms predominantly by the same radical mechanism established for other activated aromatic compounds such as 4-methylphenol. Reaction of alkaline [15N] peroxynitrite with biotarget-type molecules such as tyrosine, a tyrosine-containing tripeptide and thiol-containing amino acids allows nuclear polarisation effects to be discerned which are consistent with free and solvent-caged NO2 and HOo or CO3. The phase of the nitrate signal observed during peroxynitrite isomerisation at pH 7.4 is opposite to that observed during reaction with a biotarget-type molecule, suggesting dimerisation of NO2 to N2O4 and its subsequent hydrolysis in addition to in cage geminate pair collapse. Mechanisms in accord with the observations are suggested and their implications and extent to which they concur with established theories are discussed. Kinetic simulations are used to estimate the relative importance of nitryl chloride and peroxynitrite as in vivo reactive nitrogen species. Three furazan 2-oxide (furoxan) derivatives with potent NO- donating activity were synthesised according to literature methods and their decomposition in aqueous solution to yield NO was examined using EFR spectroscopy by spin trapping with Fe2+-N-methyl-D-glucamine dithiocarbamate (Fe2+-MGD). Ammonia, arising from thiol-mediated reductive decomposition pathways, was also detected in quantities up to approximately 8% of the nitrogen- containing decomposition products. A commercially-available enzymatic assay based on reductive amination of 2-oxoglutai-ate using L-glutamate dehydrogenase and NADPH was used. The proportion of furoxan giving rise to these products is estimated and possible mechanisms for their generation are suggested.
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Ørskov, Christensen Janne. "Evaluation of an in vitro lipid digestion model : testing poorly soluble drug substances and lipid-based formulations /." [Cph.] : Department of Pharmaceutics, The Danish University of Pharmaceutical Sciences, 2004. http://www.dfh.dk/phd/defences/jannechristensen.htm.
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Kumar, Ketan. "Product management framework for the development of automation solutions for biologics drug substance manufacturing." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/126904.
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Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, May, 2020Thesis: S.M., Massachusetts Institute of Technology, Department of Chemical Engineering, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 119-122).
This thesis presents a product management framework for the development of innovative manufacturing automation solutions, and the application of this framework to the development of automation for a continuous biomanufacturing platform at Amgen. A recently formed team at Amgen - Next Gen Automation (Drug Substance)(NGA(DS)) - is working to develop innovative automation solutions that support Amgen's strategic initiatives. Being an innovation team, NGA(DS) faces uncertainty regarding what aspects of the existing process are best suited to be improved using automation and what the best automation solutions are to achieve these results. The framework presented in this thesis provides NGA(DS) a methodology to develop useful solutions in the presence of this uncertainty. Supporting automation development for the continuous biomanufacturing platform is one of the work streams of NGA(DS), and was used as a case study for the development of the product management framework. Several prominent innovation and product management frameworks were lever-aged in the development of the framework for this project, including Lean Startup and Disciplined Entrepreneurship. As recommended by the sources studied, this project modelled innovation as a collaborative and iterative process of testing hypotheses regarding the value of the product being developed. Specific tools and concepts were applied from the source frameworks, as relevant to the teams's needs. The framework developed in this project consisted of two phases - Opportunity Analysis and Solution Development - with multiple data collection and analysis activities in each phase. Results from the activities were validated through reviews by the NGA(DS) team leadership and other relevant Subject Matter Experts within Amgen. The framework developed in this project is intended to guide future decision making for product development activities by NGA(DS).
by Ketan Kumar.
M.B.A.
S.M.
M.B.A. Massachusetts Institute of Technology, Sloan School of Management
S.M. Massachusetts Institute of Technology, Department of Chemical Engineering
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Zouzou, Michel. "Contribution à l'étude de quelques effets de l'acide borique in situ (Coleoptile de blé, hypocotyle de tournesol; Comparaison avec les acides phenylacétique et indolyl-3 acétique) et in vivo (développement de la plantule de tournesol; Croissance." Besançon, 1988. http://www.theses.fr/1988BESA2035.
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L'effet de l'acide borique sur la croissance cellulaire, dans l'obscurite ou en lumiere blanche, est precise par l'emploi des tests fragment de coleoptile de ble et d'hypocotyle de tournesol. Les resultats sont compares avec l'activite de deux de ses derives (les acides phenylboronique et diphenylborinique) et celle de deux auxines naturelles (les acides indolyl-3 acetique et phenylacetique). L'acide borique stimule l'auxesis a condition que ses trois groupements hydroxyles soient libres lors de son administration. Il agit aussi a des concentrations ou les auxines sont inactives. Par ailleurs, ce compose est capable d'accroitre la valeur du taux de germination des akenes de tournesol, de favoriser l'enracinement de la plantule issue de ses akenes et de stimuler l'allongement de l'hypocotyle. La stimulation est associee a une reduction du catabolisme auxinique au sein de l'organe eprouve. Des essais in vitro suggerent que cette reduction pourrait etre liee a la formation d'un complexe bore-enzyme inoperant
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Männlová, Adriana. "Studium biologické aktivity superabsorpčních polymerů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-316167.
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This thesis is focused on the study of the biological activity of superabsorbent polymers for environmental and agricultural applications. Generally these hydrogels perform many functions in the soil, which is increasingly stressed by treatment with synthetic fertilizers and thus loses their natural properties, such as the uptake of moisture. Addressing these issues is now in superabsorbent polymers that can absorb and also retain a lot of water around the root system as long as possible. They can perform the function of carriers gradual release fertilizer. Based on the literature review was designed and conducted the study of biological activity in the soil model on corn sown. SAPs were prepared in the framework of contract research Faculty of Chemistry of the Technical University in Brno with the company Amagro Ltd. The content of the experiment, the superabsorbent polymer, observing effects on the growth of dent corn. He was also studied root system for absorption of nutrients. Further changes were observed rheological properties of prepared superabsorbent polymer, superabsorbent polymers since they provide a source of nutrients and help to retain moisture in the soil, it is necessary to know their viskoelstick properties even at temperatures below freezing. This work is based primarily on the use of great motivation superabsorbent polymers in agriculture and also in environmental protection.
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Dunand, Christophe. "Perception d'un signal xyloglucane par des protéines membranaires et mise en évidence d'activité xyloglucane endotransglycosylane induite." Université Joseph Fourier (Grenoble ; 1971-2015), 1997. http://www.theses.fr/1997GRE10111.
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Afin de relier l'activite biologique du motif actif des xyloglucanes a la reconnaissance par des proteines membranaires, nous avons adopte une approche biochimique de detection basee sur l'utilisation de tests immunoenzymatiques. Nous avons utilise le dimere -l-fuc (12), d-gal marque avec de la digoxigenine ou de la biotine et des proteines solubilisees provenant de fractions enrichies en plasmalemme isolees de protoplastes de rubus, pour modeliser les interactions ligand-recepteur. Les resultats obtenus ont montre qu'une proteine membranaire de 62 kda est capable de fixer le dimere fuc-gal et que cette fixation est saturable et reversible. Par ailleurs, le deplacement competitif de la fixation montre une inhibition de l'activite de liaison a la fois par des analogues structuraux (xxfg, fuc-gal-glc, fuc-gal-xyl) et par des phytohormones (2,4-d, kinetine, ga#3, acide abscissique). Cependant, a ce stade de nos travaux, il n'est a pas encore etabli que ces structures proteiques correspondent a des recepteurs de xyloglucane. Une technique de determination de l'activite xyloglucane endotransglycosylase par tests immunoenzymatiques a ete mise au point et a permis de mettre en evidence une activite induite par differents signaux. Le polymere de xyloglucane marque avec de la digoxigenine et l'oligomere xxlgbsa sont utilises comme substrats pour la reaction enzymatique. Les solutions enzymatiques testees sont extraites a partir de fractions microsomales provenant de protoplastes de rubus temoins ou traites. Grace a une sequence d'anticorps (primaire, secondaire et tertiaire), l'activite transferase est suivie en mesurant l'activite peroxydase. Les avantages de cette nouvelle methode sont la sensibilite de la detection et la possibilite d'analyser plusieurs echantillons simultanement.
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Kozelková, Aneta. "Studium botnavosti a biologické aktivity hydrogelů huminových kyselin." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2013. http://www.nusl.cz/ntk/nusl-216989.
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This thesis deals with the study of the biological activity of humic substances. Based on the literature review preparation procedures were optimized in order to develop new hydrogel forms containing humic substances and biopolymers with high swelling capacity. Besides methodology for the rapid assessment of the biological activity obtained in laboratory conditions were designed and tested. The experimental part focused on characterization of hydrogel samples by means of routine physico-chemical methods, the main attention was paid to sorption of water and release of humic substances into solution. Then the prepared hydrogel materials were tested focusing on the growth effects on the maize. The absorption of mineral nutrients by the roots of plants were studied as well. The motivation of this work comes from the potential of agricultural and environmental applications of such hydrogel materials resulting in a renewal of previously exhausted organic content of soils and consequent interruption of substantial soil degradation.
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Grove, Mette. "Development and characterisation of lipid-based formulations for oral delivery of poorly soluble drug substances /." Cph. : The Danish University of Pharmaceutical Sciences, Department of Pharmaceutics and Analytical Chemistry, 2006. http://www.dfuni.dk/index.php/Mette_Grove/3071/0/.
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Howard, Patricia Ann. "Analysis of mesh strategies for rapid source location in chemical/biological attacks." Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0430104-144332.
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Mitra, Ganguli Tora. "Modulation of Voltage-Gated N-Type Calcium Channels by G Protein-Coupled Receptors Involves Lipids and Proteins: A Dissertation." eScholarship@UMMS, 2008. https://escholarship.umassmed.edu/gsbs_diss/389.
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Pain signaling involves transmission of nociceptive stimuli in the spinal cord where a critical balance between excitatory and inhibitory inputs determines the response to noxious stimuli. The neuropeptide, substance P (SP), mediates transmission of pain in part by binding to the tachykinin receptor (NK-1R) in the dorsal horn (DH) of the spinal cord. One of SP’s downstream effects is to modulate N-type Ca2+(N-) channels. While phospholipid breakdown is a part of the inflammatory process that accompanies tissue damage, the role of this metabolic pathway has not been completely described with respect to N-channel modulation during pain signaling. Despite the incomplete understanding of this modulation, pharmacological antagonists of both NK-1R and N-channels have been used to treat pain.
In Chapter II, using whole-cell patch clamp recording techniques, the SP signaling cascade that mediates inhibition of recombinant N-channel activity was characterized. By adopting a pharmacological approach, I show that this pathway resembles the slow pathway that was earlier described for modulation of N-current by the M1 muscarinic receptor (M1R). M1R couples to Gq to stimulate phospholipid breakdown. Together with previous observations, the data presented in this chapter provide evidence for involvement of the extracellular receptor kinase (ERK1/2), phospholipase A2 and release of phospholipid metabolites in the modulation of N-current by SP. Overall, this chapter shows that phospholipid metabolism involved in modulation of N-currents is not specific to M1Rs but that other Gq-coupled receptors may also modulate N-currents via the same signal transduction pathway.
In Chapter III, enhancement of N-current by SP was studied as part of a collaborative project to understand current enhancement that occurs when a palmitoylated accessory CaVβ2a subunit is co-expressed with the pore-forming subunit CaV2.2 and the accessory subunit α2δ-1. When CaVβ3 is present, SP inhibits N-current as described in Chapter II. However, when palmitoylated CaVβ2a is co-expressed with CaV2.2 (and α2δ-1), current enhancement is observed at negative test potentials, demonstrating that both M1Rs and NK-1Rs exhibit the same profile of N-current modulation. This change in modulation by muscarinic agonists is not observed in the presence of a depalmitoylated CaVβ2a. However a chimeric CaVβ2aβ1b subunit that contains the palmitoylated N-terminus from CaVβ2a confers enhancement. Normally expression of the β1b subunit resulted in current inhibition. These findings indicated that the palmitoylated CaVβ2a participates in enhancement of current. Our data support a model where inhibition dominates over enhancement; when inhibition is blocked, enhancement may be observed. Lastly, we show that N-current inhibition by SP is minimized when exogenous palmitic acid is applied to cells co-expressing CaVβ3 subunits with N-channels. These results indicate that the presence of palmitic acid can prevent N-current inhibition when SP is applied most likely by interacting with CaV2.2. We propose a model where palmitic acid occupies the inhibitory site and serves to antagonize inhibition by a lipid metabolite, which is most likely arachidonic acid. The CaVβ2a protein seems to have a role in positioning the palmitoyl groups near CaV2.2. This chapter provides a new role for protein palmitoylation where the palmitoyl groups of CaVβ2a are both necessary and sufficient to block inhibition of another protein: CaV2.2.
In Chapter IV, I probe the role of the relative orientation of CaVβ2a and the pore-forming subunit of the N-channel in N-current modulation. Evidence is presented that shows that not just the presence of a palmitoylated CaVβ2a is necessary, but the relative orientation of CaVβ2a to CaV2.2 is critical for blocking inhibition. Using N-channel mutants that cause a change in the orientation of CaVβ2a relative to CaV2.2, I show that the block of inhibition is disrupted; inhibition by the slow pathway is rescued. These findings further support my model that the palmitoyl groups of CaVβ2a normally reside in a specific location that overlaps with the slow pathway inhibitory site on CaV2.2. Lastly I present data showing that the enhancement of N-current, observed when palmitoylated CaVβ2a is present, occurs via the slow pathway.
In Chapter V the effect of CaVβ’s orientation on N-channel modulation by the dopamine D2 receptor is tested. In this form of modulation, inhibition is rapid and voltage-dependent. The signaling pathway is membrane-delimited since Gβγ, released after receptor stimulation, directly interacts with the N-channel at a site that overlaps with a high affinity binding site for CaVβs. While N-currents are modulated by this pathway, the deletion mutants show aberrant membrane-delimited modulation. The findings in this chapter further underscore the importance of proper positioning of CaVβ to CaV2.2 for eliciting proper N-current modulation after GPCR stimulation.
Overall, the data presented in this dissertation provides a mechanistic approach into examining modulation of N-current by different GPCRs via two different signaling pathways as well as the role CaVβ subunits serve in each modulatory pathway.
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Mohd, Fauzi Fazlin Binti. "In silico target prediction : applications to traditional medicine and novel psychoactive substances and the extension to biological space." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708743.
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Switalla, Simone [Verfasser]. "Characterization of local respiratory irritation and inflammation after acute exposure to biological and chemical substances in PCLS / Simone Switalla." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2011. http://d-nb.info/1013364341/34.
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Florentin, Irène. "Caracterisation fonctionnelle comparative de substances immunomodulatrices." Paris 6, 1987. http://www.theses.fr/1987PA066374.
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Zebiri, Ilhem. "Etude phytochimique et biologique de cinq espèces de la flore péruvienne. Evaluation de leurs propriétés antileishmanienne et cytotoxique." Thesis, Reims, 2015. http://www.theses.fr/2015REIMS043/document.
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Ce travail présente l’étude phytochimique de cinq plantes péruviennes, Myrsine latifolia, M. congesta et M. sessiliflora (Primulaceae ex Myrsinaceae), Poraqueiba sericea (Icacinaceae) et Dendrobangia boliviana (Cardiopteridaceae ex Icacinaceae). L’étude des trois Myrsine nous a permis d’isoler onze composés déjà connus dans la littérature qui ont été testés pour leurs activités antileishmanienne (criblage sur Leishmania infantum promastigotes en luminescence) et cytotoxique (test in vitro sur des fibroblastes). Les résultats étaient négatifs pour les deux activités. A partir des tiges de Poraqueiba sericea nous avons pu isoler onze composés dont six triterpènes et trois saponines monodesmosides décrits pour la première fois dans cette famille de plante et deux sécoiridoïdes. Différentes activités biologiques ont été évaluées pour ces molécules : activités leishmanicide, cytotoxique et anti-élastase. Seuls les derniers tests ont révélés des activités pour deux tripterpénoïdes et pour le secologanoside. A partir de Dendrobangia boliviana quatorze saponines ont pu être isolées dont douze sont de nouveaux glycosides des acides serjanique ou phytolaccinique. L’analyse en LC-RMN a permis d’identifier cinq autres saponines de structures nouvelles. Ces composés ont été testés pour leurs activités biologiques et n’ont démontré aucune activité hémolytique et trois d’entre eux ont révélé une cytoxicité sur les fibroblastes. Les tests antileishmaniens n’ont révélé aucune activité. En bioautographie (HPTLC) ces saponines présentent un potentiel intéressant pour différentes activités biologiques (tyrosinase, α et β-glucosidases et acétylcholinestérase)This work presents the phytochemical study of five Peruvian plants, Myrsine latifolia, M. congesta and M. sessiliflora (Primulaceae ex Myrsinaceae), Poraqueiba sericea (Icacinaceae) and Dendrobangia boliviana (Cardiopteridaceae ex Icacinaceae). The study of the three Myrsine enabled us to isolate eleven compounds already known in the literature which were tested for their antileishmanial (screening of Leishmania promastigotes luminescence) and cytotoxic activities (in vitro test on fibroblasts). The results were negative for both activities. From the stems of Poraqueiba sericea we were able to isolate eleven compounds including six triterpenes, three monodesmosides saponins described for the first time in this plant family and two secoiridoides. Various biological activities have been evaluated for these molecules: leishmanicidal, cytotoxic and anti-elastase activities. Only the last testing has suggested activities for two tripterpénoïdes and the secologanoside. From Dendrobangia boliviana fourteen saponins have been isolated including twelve novel glycosides of the serjanique or phytolaccinique acids. The analysis by LC-NMR allowed us to identify five other saponins with new structures. These compounds were tested for their biological activities and showed no hemolytic activity and three of them showed a cytotoxicity on fibroblasts. The antileishmanial test showed no activity. In bioautography (HPTLC) these saponins showed an interesting potential for different biological activities (tyrosinase, α and β-glucosidase and acetylcholinesterase)
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Gupta, Abhinav. "Characterization and treatment of UV quenching substances and organic nitrogen in landfill leachates and thermal hydrolysis/anaerobic digestion centrate." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/22049.
Full textAbstract:
Landfill leachates and thermal hydrolysis pretreated anaerobic digestion centrate can quench UV light at publically owned treatment works (POTWs). Increased eutrophication, has led to tightening of nutrient discharge limits in some regions of the country. Biologically recalcitrant organic nitrogen, adds to effluent nitrogen making it difficult to meet these requirements.The study aimed at characterizing landfill leachate and centrate fractions to develop an understanding that might help design on-site treatment methods. Leachates varying in on-site treatment and ages were fractionated on basis of hydrophobic nature. Humic substances were the major UV light quenching fractions. Majority of the humic substances were > 1 kDa molecular weight cut off (MWCO) indicating that membrane treatment might be effective for UV quenching substances removal. UV absorbing substances were found to be more bio-refractory than organic carbon. Significant decrease in humic substances with long term landfilling indicated that age was important in determining the potential for leachates to impact the UV disinfection. Organic nitrogen was observed to be hydrophilic in nature (mostly < 1 kDa). Proteins which are easily biodegradable contributed around one-third of the organic nitrogen.
For thermal hydrolysis centrate, the optimum treatment depended on particle size and hydrophobic nature. Biological treatment was observed to be more effective for the removal of
organic matter and UV254 quenching substances for fractions < 300 kDa. Biological treatment had little impact on organic nitrogen. Coagulation-flocculation is an effective treatment for higher molecular weight (MW) fractions whereas a membrane bioreactor would be more suitable for smaller MW fractions.
Master of Science
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David, Jan. "Produkce, charakterizace a návrh aplikací regenerovaných huminových kyselin." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-233322.
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Předkládaná disertační práce se zabývá huminovými látkami (HL), zejména huminovými kyselinami a jejich solemi, tj. humáty. V práci je prezentována literární rešerše o huminových látkách, stručně je zmíněna historie výzkumu huminových látek, obsáhle jsou pak prezentovány práce o jejich struktuře a supramolekulovém uspořádání. Jsou též zmíněny metody extrakce huminových látek z různých zdrojů. Dále jsou v tomto pojednání zařazeny a diskutovány práce zabývající se biologickými „hormonálními“ vlastnostmi HL. Z hlediska chemie životního prostředí jsou zmíněny zejména sorpční vlastnosti HL. Popsané průmyslové aplikace HL pak zahrnují celou řadu patentů a publikovaných prací, zabývající se využitím huminových látek jakožto barviv či přísad do polymerů, atd. V experimentální části je popsána příprava regenerovaných lignitů, z nichž jsou dále extrahovány huminové kyseliny a připraveny huminové soli, tzv. humáty. Princip regenerace spočívá v oxidaci původního lignitu širokou koncentrační řadou kyseliny dusičné a peroxidu vodíku. K charakterizaci získaných huminových materiálů je výhodně použit nový přístup, kdy jsou kombinovány výsledky z analýz chemických (elementární analýza, infračervená spektroskopie, termogravimetrie) a fyzikálně-chemických (dynamický rozptyl světla, spektrometrie relaxační nukleární magnetické rezonance, vysoceúčelná velikostně-vylučovací chromatografie a fluorescenční spektrometrie se zhodnocením hydratace humátů pomocí vysocerozlišovací ultrazvukové spektrometrie a hustoměru). Tyto metody jsou navíc položeny do kontextu s charakterizací biologické aktivity humátů, která je provedena pomocí modifikované metody založené na měření délky a hmotnosti kořenů kukuřice a laterálních kořenů. V závěru je použit statistický přístup s využitím Pearsonova korelačního koeficientu a jsou též (na základě výsledků pilotních studií) navrženy dvě potenciální environmentální aplikace regenerovaných huminových materiálů – sorpce antibiotika tetracyklinu a využití regenerovaného lignitu jako zdroje zkvasitelných cukrů.
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Johnson, Robert Jean. "Plant growth regulators : an alternative to frequent mowing /." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA232051.
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Thesis (M.S. in Management)--Naval Postgraduate School, June 1990.Thesis Advisor(s): Carrick, Pual M. "June 1990." Description based on signature page. DTIC Identifier(s): Plant growth regulators, growth indicators. Author(s) subject terms: Plant growth regulators, growth indicators. Includes bibliographical references (p. 39-40). Also available online.
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Fernandez, Nadia. "Separation et etude des composants de liaison cellulaires fixant les substances aromatiques polycycliques." Toulouse 3, 1987. http://www.theses.fr/1987TOU30247.
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Miller, Mark W. "Optimizing high-rate activated sludge: organic substrate for biological nitrogen removal and energy recovery." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/78208.
Full textAbstract:
Although the A-stage high-rate activated sludge (HRAS) process destroys some of the chemical energy present in municipal wastewater, this process has been gaining attention as a viable technology for achieving energy neutrality at water resource recovery facilities. In addition to carbon capture for energy recovery, A-stages are also being utilized upstream of shortcut biological nitrogen removal (BNR) processes as these BNR processes often require a controlled influent carbon to nitrogen ratio that is lower than required for conventional BNR processes. While there is extensive knowledge on conventional activated sludge processes, including process controllers and activated sludge models, there has been little detailed research on the carbon removal mechanisms of A-stage processes operated at solids retention times (SRT) less than about one day.
The overall objective of this study was to elucidate the chemical oxygen demand (COD) removal mechanisms of short SRT activated sludge processes with a specific focus on the removal of the different COD fractions under varying operating conditions including dissolved oxygen, hydraulic retention time, temperature, and SRT. Once understood, automatic process control logic was developed with the purpose of producing the influent characteristics required for emerging shortcut BNR processes and capturing the remaining COD with the intent of redirecting it to an energy recovery process.
To investigate the removal and assimilation of readily biodegradable substrate (SS), this study evaluated a respirometric method to estimate the SS and active heterotrophic biomass (XH) fractions of the raw wastewater influent and effluent of an A-stage pilot process. The influent SS values were comparable to the SS values determined using a physical-chemical method, but the effluent values did not correlate well. This led to the measurement of the heterotrophic aerobic yield coefficient and decay rate of the pilot process. The yield coefficient was estimated to be 0.79±0.02 gCOD/gCOD, which was higher than the accepted value of 0.67 g/g. It was speculated that the batch respirometry tests resulted in the aerobic storage of SS and this likely contributed to the error associated with the determination of SS and XH. Therefore, physical-chemical fractionation methods were used to determine the removal of the individual COD fractions. It was concluded that the SRT was the primary control parameter and below a 0.5 day SRT the dominate COD removal mechanisms were assimilation and oxidation of readily degradable substrate and sedimentation of particulate matter. At SRTs between 0.5-1 days, COD removal became a function of hydrolysis, as adsorption of particulate and colloidal matter was maximized but not complete because of limited adsorption sites. Once adequate adsorption sites were available, effluent quality became dependent on the efficiency of bioflocculation and solids separation. While the SRT of the pilot process could not be directly controlled because of severe biofouling issues when using in situ sensors, a MLSS-based SRT controller was successfully implemented instead. The controller was able to reduce total COD removal variation in the A-stage by 90%. This controller aslo provided the capability to provide a consistent carbon to nitrogen ratio to the downstream B-stage pilot process.
To ascertain the settling, dewaterability, and digestibility of the sludge produced by the pilot A-stage process, several standardized and recently developed methods were conducted. The results from these tests indicated that the A-stage had similar dewaterability and digestibility characteristics to primary sludge with average achievable cake solids of 34.3±0.4% and average volatile solids reduction (VSR) of 82±4%. The A-stage sludge also had an average specific methane yield of 0.45±0.06 m3CH4/kgVS. These results were attributed to low extracellular polymeric substance (EPS) content. However, further research is needed to better quantify EPS and determine the effect of HRAS operating parameters on EPS production. Overall the A/B pilot study was able to capture 47% of the influent COD as waste sludge while only oxidizing 45% of the influent COD. Of the COD captured, the A-stage contributed over 70% as dry solids. Coupled with high sludge production, VSR, and methane yield the A/B process was able to generate 10-20% more biogas and 10-20% less dry solids after anaerobic digestion than a comparable single-sludge BNR process.Ph. D.
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Buś, Tanja [Verfasser], Ulrich Sigmar [Gutachter] Schubert, and Thomas [Gutachter] Heinze. "The enhanced delivery of biologically active substances by tailor-made polymers / Tanja Buś ; Gutachter: Ulrich Sigmar Schubert, Thomas Heinze." Jena : Friedrich-Schiller-Universität Jena, 2019. http://d-nb.info/1206605014/34.
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Кіндя, Валерій Ілліч, Валерий Ильич Киндя, and Valerii Illich Kindia. "Концентрація деяких біологічно активних сполук в соєвій олії, отриманой методом пересування з бобів, вирощених в умовах Сумської області." Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/32161.
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Метою нашої роботи було вивчити вміст токоферолів, стеринів и фосфоліпідів в двох зразках соєвої олії, отриманої екструзийним способом із соєвих бобів, вирощених в умовах Сумської області.
При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/32161
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Sloss, Ian. "The effects of ethanol on memory and neuroplasticity in a vertebrate and an invertebrate model of learning." Thesis, University of Sussex, 2016. http://sro.sussex.ac.uk/id/eprint/65381/.
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Binge drinking is characterised by cycles of ethanol intoxication and withdrawal and is thought to be highly deleterious for the normal functioning of the nervous system. The behavioural and neurophysiological consequences of rapid escalation of blood alcohol concentration and subsequent withdrawal, and their effects on learning and memory and underlying neural circuitry can be studied in suitable animal models. Here, spatial and instrumental learning as well as hippocampal LTP were assessed in C57BL/6J mice for the effects of adolescent intermittent ethanol (AIE) and other ethanol treatments. AIE treatment did not impair spatial or non-spatial memory when tested in adulthood. However, if mice were trained whilst intoxicated during AIE treatment, spatial memory was impaired. Post-training injections of ethanol impaired performance in operant conditioning. A rapid rise and fall in ethanol concentration, prior to stimulation, blocked LTP induction in drug naïve hippocampal slices; an effect that was not seen if the ethanol concentration was gradually increased and decreased. Moreover, AIE treatment caused an NMDA receptor-dependent transient increase in hippocampal LTP. The second part of this study used a novel molluscan model Lymnaea stagnalis and demonstrated that high concentrations of ethanol blocked acquisition and retrieval of an associative memory. However, if acquisition occurred in the presence of ethanol then memory could also be retrieved under ethanol, demonstrating ethanol state dependency. By utilising the cerebral giant cells, a modulatory neuron type with known involvement in memory formation, it was found that ethanol reduced the tonic firing frequency as well as the peak-to-trough and half-width parameters of individual action potentials. The development of in vivo and in vitro ethanol treatment and test protocols, and the findings based on their use, open up new avenues for future systematic investigations on ethanol's effects on behaviour and underlying neural circuitry in both vertebrate and invertebrate model systems.
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Ballade, Tosco Armelle. "Identification et caractérisation par spectrométrie de masse de substances à activités biologiques produites par des souches de BacillusS." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14240.
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Les substances synthétisées par les bactéries du genre Bacillus présentent un grand intérêt en raison de leurs nombreuses activités antimicrobiennes. L’objectif de ce travail a consisté à mettre au point un protocole analytique fiable pour extraire ces substances, et les caractériser par spectrométrie de masse et par leurs activités biologiques. Une première approche par spectrométrie de masse MALDI-ToF ne nous a pas donné de résultats satisfaisants en raison d’un phénomène de suppression spectrale. Une seconde stratégie d’étude combinant deux techniques analytiques a alors été envisagée. Les composés et les familles lipopeptidiques ont d’abord été séparés par chromatographie liquide analytique et analysés en ligne en mode de couplage ESI-IT. Ensuite les fractions collectées ont été caractérisées par spectrométrie de masse MALDI-Q-ToF (et ESI-Q-ToF) pour déterminer les masses exactes et obtenir des spectres de fragmentation complémentaires des premiers. Ce procédé nous a permis d’établir des critères d’identification des composés et des familles de lipopeptides de structures connues. Cette caractérisation est basée sur des temps de rétention en chromatographie, des mesures de masses exactes et sur des schémas de fragmentations. Nous avons fait de même avec les composés non identifiés et ensuite évalué leur activité biologique en réalisant des tests de diffusion sur agar. Cette stratégie d’étude permet de faire un criblage de l’ensemble des biomolécules produites par des souches de Bacillus et de relier une structure à une activité biologique. Ce protocole, mis au point pour des cultures réalisées en milieu liquide, a ensuite été adapté aux cultures sur boîtes de Pétri pour pouvoir analyser les composés produits à l’échelle de la colonie bactérienneCompounds produced by Bacillus bacteria present a major interest because of their biological activities. The aim of this work was to develop a reliable analytical methodology to extract these compounds, and to characterize them by mass spectrometry and by their biological activities. A first approach by MALDI-ToF mass spectrometry doesn’t give satisfactory results because of strong spectral suppression effects. Therefore, we have designed a second strategy which combined two analytical technologies. First, compounds and lipopeptides families were separated by analytical liquid chromatography and analysed by ESI-IT. Then, collected fractions were characterized by MALDI-Q-ToF (and ESI-Q-ToF) in order to determine accurate mass measurements and obtain complementary product ion spectra. This process led us to establish identification criteria of compounds and lipopeptides families which have known structures. This characterization is based of retention times in chromatography, accrurate mass measurements and fragmentation schemes. We have achieved the same experiments with non identified compounds and then assessed their biological activity by agar well diffusion test.This strategy allows to obtain a screening of whole of the biomolecules produced by bacillus strains and establishes a link between structure and biological activity. This methodology, designed for cultures in liquid medium, was then adapted to cultures in Petri disches in order to analyse compounds producted at the bacterial colony scale