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Efeitos ecotoxicológicos das nanopartículas de dióxido de titânio sobre a alga Pseudokirchneriella Subcapitata e sobre o Cladócero Ceriodaphnia Silvestrii por diferentes vias de exposição / Ecotoxicological effects of the titanium dioxide nanoparticles on the algae Pseudokirchneriella subcapitata and on the cladoceran Ceriodaphnia silvestrii by different exposure routesLucca, Gisele Maria de 10 June 2016 (has links)
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Previous issue date: 2016-06-10 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / In recent years, increased use of titanium dioxide nanoparticles (TiO 2 NPs) in consumer
products and technological devices has raised concerns regarding their environmental
impacts and their risks to human health. Ecotoxicological studies have been used as a tool to analyze the toxic potential of TiO 2 NP S in different trophic levels, such as primary
producers (algae) and first order consumers (cladocerans). In the present study, the
chronic effects of TiO2 NPS on the population growth of the microalgae chlorophycean
Pseudokirchneriella subcapitata was evaluated during an exposure period of 96 hours,
under conditions of temperature and photoperiod similar to those found in tropical
ecosystems. New methods were developed for the separation of the aggregates between
the algae cells and TiO2 NPS, whose formation was observed at above 0.01 mg L-1
concentrations after a period of 96 hours’ exposure. The only effective method was the
one in which the cells were washed three times with a metal chelator (EDTA), with
duration of 1 minute for each wash. In the toxicity chronic test, there was obtained a
significant inhibition of algal growth from the concentration of 64 mg L-1 of TiO2 NPs,
with a concentration of 50% inhibition of algal cells (96 h - IC50) of 201.22 mg L -1 in 96
h of exposure. Then, it was evaluated the acute effects of exposure by contact and the
chronic effects of TiO2 NPs for the cladoceran Ceriodaphnia silvestrii, using
contaminated food (Pseudokirchneriella subcapitata) as a route of exposure. In acute
toxicity tests was obtained the average value of EC50 - 48 h of 77.57 mg L-1. In chronic
toxicity tests, it was observed significant differences in survival from the concentration
of 0.01 mg L-1, while for the body length, the number of eggs and neonates produced,
toxic effects were observed from the concentration of 1 mg L-1. These results indicate that
the nano-TiO2 NPS had a deleterious effect on the growth of Pseudokirchneriella
subcapitata only at concentrations above those normally found in natural aquatic
environments. For the cladoceran Ceriodaphnia silvestrii, the route of dietary exposure
indicated a greater toxic effect. / Nos últimos anos, o aumento do uso das nanopartículas de dióxido de titânio (nano-TiO2)
em produtos de consumo e em dispositivos tecnológicos tem gerado preocupações
relativas aos seus impactos ambientais e seus riscos à saúde humana. Estudos
ecotoxicológicos têm sido utilizados como uma ferramenta para analisar o potencial
tóxico das nano-TiO2 em diversos níveis tróficos, tais como produtores primários (algas)
e consumidores de primeira ordem (cladóceros). No presente estudo, os efeitos crônicos
das nano-TiO2 sobre o crescimento populacional da microalga clorofícea Pseudokirchneriella subcapitata foi avaliado durante um período de exposição de 96 horas, sob condições de temperatura e de fotoperíodo semelhantes às encontradas em ecossistemas de regiões tropicais. Foram desenvolvidas novas metodologias para separação dos agregados entre as células algais e as nano-TiO2, cuja formação foi
observada nas concentrações acima de 0,01 mg L -1 após um período de exposição de 96
horas. O único método eficiente foi aquele em que as células foram lavadas três vezes
com um quelante de metal (EDTA), com duração de 1 minuto para cada lavagem. No
teste de toxicidade crônico obteve-se inibição significativa do crescimento algal a partir
da concentração de 64 mg L-1 de nano-TiO2, com uma concentração de inibição a 50%
das células algais (CI 50 - 96h) de 201,22 mg L-1 em 96 h de exposição. Em seguida, foram
avaliados os efeitos agudos via exposição por contato e os efeitos crônicos das nano-TiO2
para o cladócero Ceriodaphnia silvestrii, utilizando o alimento (Pseudokirchneriella
subcapitata) contaminado como via de exposição. Nos testes de toxicidade aguda foi
obtido o valor médio de CE50 - 48 h de 77,57 mg L-1. Nos ensaios de toxicidade crônica,
diferenças significativas foram observadas na sobrevivência a partir da concentração de
0,01 mg L -1, enquanto que para o comprimento corporal, o número de ovos e o número
de neonatas produzidos, os efeitos tóxicos foram observados a partir da concentração de
1 mg L-1. Tais resultados indicam que as nano-TiO2 possuíram um efeito deletério sobre
o crescimento de Pseudokirchneriella subcapitata somente em concentrações acima
daquelas normalmente encontradas em ambientes aquáticos naturais. Para o cladócero
Ceriodaphnia silvestrii, a via de exposição alimentar indicou um maior efeito tóxico. / CNPq: 305698/2013-30 / FAPESP: 2014/14139-3 e 2016/00753-7
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BREWERS’ SPENT GRAIN CONVERSION TO VALUE-ADDED CHEMICALS BY LAB-SYNTHESIZED HETEROGENEOUS PHOTOCATALYSTS UNDER VISIBLE LIGHT AND MILD CONDITIONSBaral, Sudip 01 September 2021 (has links)
Over the last several decades, there have been a tremendous developments and greatinnovations in photocatalysis process along with the development of efficient nanosized catalysts for simple approach and economic viability. In this study, magnetic core@doubleshell nanomaterials were investigated and synthesized in lab with three-step innovative approach where Fe3O4 nanoparticles (NPs) were produced first to act as cores without using any surfactants. The magnetite/silica core–shell structure was then prepared by hydrolysis of tetraethoxysilane (TEOS) in the presence of core particles under alkaline conditions. And the outermost shell, the α-Fe2O3/TiO2 nanoparticles, were grown over magnetic core of Fe3O4@SiO2 using coprecipitation and calcination method. Furthermore, the Fe3O4@SiO2@α-Fe2O3/TiO2 NPs were then loaded on the reduced graphene oxide (r-GO) using hydrothermal method and are also mixed by kneading with the layered double hydroxides (LDH) of Mg2+ and Al3+. These nanoparticles were characterized with scanning electron microscope (SEM), transmission electron microscope (TEM), dynamic light scattering (DLS), and energy dispersive X-ray spectroscopy (EDS). Different model compounds like microcrystalline cellulose (90 μm), D-xylose, and sodium lignosulfonate representing cellulose, hemicellulose, and lignin, respectively, were converted to valuable chemicals with different NPs under visible light for different time periods. For example, valeric acid (VA) and vanillylmandelic acid (VMA) were produced when cellulose was used for the conversion with core-double shell NPS which were quantified using high performance liquid chromatography (HPLC). Similar approach was adopted for the conversion of brewers’ spent grain (BSG), a lignocellulosic biomass, without oxygen under visible light, which yielded ethanol as the main product along with other sugars and acids of very low concentrations. The magnetic property of the nanomaterials made it easy for recycle and reuse. From a sustainability point of view, this study will fill a large need in the biomass photocatalysis field by developing core-shell multi-functional photocatalysts for direct transformation of lignocellulose into valuable chemicals under low temperatures, atmospheric pressure, and visible light from the sun.
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A comprehensive modeling approach for BMP impact assessment considering surface and ground water interactionCho, Jae-Pil 12 June 2007 (has links)
The overall goal of this study was to develop a comprehensive tool for assessing the effectiveness of selected BMPs on both hydrology and water quality and to demonstrate the applicability of the system by considering 1) temporally and spatially changing land use management practice in an agricultural watershed and 2) interaction between surface and ground water over the entire system. A user interface and Dynamic Agricultural Non-point Source Assessment Tool (DANSAT) were developed to achieve this goal. DANSAT is the only distributed-parameter, physically-base, continuous-simulation, and multi-soil layer model for simulating impacts of agricultural BMPs on hydrology and water qulality in small agricultural watersheds. DANSAT was applied to QNB plot (18m à 27m) and two agricultural watersheds in Virginia, including Owl Run watershed (1140 ha) and QN2 in the Nomini Creek watershed (216 ha), to evaluate the model components and its performance in predicting runoff, sediment yield, and pesticide load. DANSAT performed well in predicting total runoff and temporal variations in surface runoff for both field-scale and watershed-scale applications. Total percent errors between the measured and predicted results were less than 10% except for one case (39.8% within a subwatershed of Owl Run watershed), while the daily Nash-Sutcliffe model efficiencies were greater than 0.5 in all applications. Predicted total sediment yields were within ±35% of observed values in all applications. However, the performance of DANSAT in predicting temporal trend and spatial distribution of sediment loads was acceptable only within Owl Run watershed, where high correlations between flow rates and sediment loads exist. The predicted total pesticide loads were within ±100% of observed values. DANSAT failed to simulate the temporal occurrence of pesticide loads with a 0.42 daily Nash-Sutcliffe efficiency value. The Dual-Simulation (DS) was developed within the linked ground water approach to resolve problems encountered due to the existence of different temporal scales between DANSAT and the existing ground water models such as MODFLOW and MT3D. The linked approach performed better in predicting the seasonal trend of total runoff compared to the integrated approach by showing an increase in monthly Nash-Sutcliffe efficiency value from 0.53 to 0.60. Surface and subsurface output variables were sensitive to the changes in spatially distributed soil parameters such as total porosity and field capacity. A maximum grid size of 100 m was recommended to be appropriate for representing spatial distribution of topographic, land use, and soil characteristics based on accuracy analysis during the GIS manipulation processes. Larger time-step based on predefined acceptable maximum grid size, decreased the computational time dramatically. Overall sensitivity to different grid sizes and time-steps was smallest for hydrology components followed by sediment and pesticide components. Dynamic crop rotation was considered by DANSAT, and the model successfully simulated the impacts of temporal and spatial changes in crop rotations on hydrology and water quality for both surface and subsurface areas. DANSAT could prove to be a useful tool for non-point source pollution managers to assess the relative effectiveness of temporally and spatially changing BMPs on both surface and ground water quantity and quality. / Ph. D.
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<b>ECONOMIC STUDIES OF MAPLE SYRUP CONSUMERS AND PRODUCERS IN INDIANA</b>Jean Fritz Saint Preux Sr (19184893) 21 July 2024 (has links)
<p dir="ltr">Extensive tree-cutting operations and prioritization of crop production a century ago caused a significant decline in maple syrup production in Indiana. Today, there is an increasing consumer interest in natural and locally produced food, creating potential for regrowth in the industry. Understanding both production and consumption behaviors is crucial to capitalize on this potential and ensure sustainable sugarbush resources in the state. This thesis comprised two chapters, presenting the findings on consumers and producers, respectively. The first chapter examined the factors influencing consumers' behavior toward maple syrup purchase and satisfaction. Results suggested that suburban residency, education, age, income, and lifestyle factors – such as visiting farmers' markets and purchasing organic food – may influence consumers' attitudes toward purchasing maple syrup. Moreover, consumers who purchase organic food tended to be satisfied with maple syrup and were more likely to recommend it to others. The second chapter explored the factors motivating maple syrup producers to manage their forests and investigated whether crowd-in or crowd-out effects exist among different management practices. I used logistic regressions to identify relationships among the adoption of a variety of forest management practices and a variety of independent variables, using data pooled from two producer surveys conducted in Indiana in 2022 and 2023, respectively. Production as a hobby, owning a sugarbush, and production capacity all positively affected the likelihood of management practice adoption. In addition, crowding-in effects were identified in adopting forest management practices, suggesting that producers were more likely to adopt multiple practices simultaneously. These chapters emphasized the importance of understanding maple syrup consumer socio-demographic characteristics for effective marketing strategies and producer behavior for sustainable production practices to promote industry growth.</p>
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Stormwater evaluation and site assessment - a multidisciplinary approach for stormwater Best Management Practices (BMPs)Padmanabhan, Aarthi January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Lee R. Skabelund / Stormwater management is typically approached from different perspectives by practicing professionals. As such, stormwater planning/design is not always completed as a multi-disciplinary coalition of experts using holistic and synergistic methods.
For a number of years, engineers and design professionals, particularly landscape architects, have been employing various strategies and techniques to address on-site stormwater management in terms of water quality and quantity. There is increasing awareness that in order to create solutions that are effective over both the short and long-term a landscape architect’s approach needs to account for the health, safety and welfare perspectives carried by engineers, the unique aspects of particular project sites, their surroundings and bio-regional context, as well as the perceptions of clients, other key stakeholders, and the broader public.
This research investigates the various criteria integral to developing an analytic framework for ecologically-appropriate stormwater planning/design (Sustainable Stormwater Evaluation and Site Assessment or SSWESA). SSWESA is proposed as a type of decision-tree for site analysis of sustainable systems pertaining to stormwater. Using the SSWESA process is expected to help researchers and professionals make better planning and design decisions as they select and implement appropriate best management practices (BMPs) for a given site and context.
My intent in developing SSWESA is to help designers assess existing and potential stormwater functions at the site scale in order to promote sustainable planning and design based upon the important principle: “First, do no harm”. It is also my intent to promote further research related to sustainability by providing references and sources from experts in the various fields related to ecologically-based stormwater management.
A review of the literature related to ecological factors relevant to low impact stormwater management assisted in the development and refinement of the criteria for stormwater assessment and evaluation. In this report, the SSWESA framework is tested on a public school property in Manhattan, Kansas to demonstrate how the framework is applied and to understand the questions and issues that arise from its use.
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Evaluating and expanding knowledge and awareness of health professionals on the consumption and adverse consequences of Novel Psychoactive Substances (NPS) through innovative information technologic toolsSimonato, Pierluigi January 2015 (has links)
Background: The rapid diffusion of Novel Psychoactive Substances (NPS) constitutes an important challenge in terms of public health and a novelty in clinical settings, where these compounds may lead to erratic symptoms, unascertained effects and multi-intoxication scenarios, especially in emergency situations. The number of NPS available on the illicit drug market is astonishing: official reports suggest the appearance of a new drug every week. NPS may be enlisted in many different families such as synthetic phenethylamines, tryptamines, cathinones, piperazines, ketamine-like compounds, cannabimimetics and other plant-derived, medical products and derivatives. Therefore, healthcare services and professionals are often called to face this unknown 'galaxy' where NPS users seem to perceive traditional services 'unfitting' for their needs, requiring an attention which is quite different from known classic drug abusers. In this context, the Recreational Drugs European Network (ReDNet), a research project funded the European Commission and led by the University of Hertfordshire, aimed to explore the NPS galaxy and develop information tools for vulnerable individuals and professionals working with them. This initiative reported specific Technical Folders on new drugs and disseminated the collected information through innovative communication technologies (e.g. multimedia tools, social networking and mobile phone services) internationally. Aim and objectives: The aim of this work is to evaluate and contribute to expand the knowledge of health professionals on NPS. The key objectives are: 1) to assess the level of knowledge on NPS amongst a sample of Italian healthcare professionals; 2) to evaluate the effectiveness of dissemination tools developed by ReDNet, including an SMS-Email/mobile service (SMAIL); 3) to understand the clinical impact of NPS by providing four Technical Folders and collecting two clinical cases on NPS. Methodology: According to the objectives, the methodological approach has been articulated in the following three phases. Phase 1: investigating knowledge and preferred channels of information via an online survey among health professionals in Italy. This first Italian study on NPS awareness had been online from February to July 2011, recruiting participants from Departments of Addiction, Psychiatry and other services. Phase 2: evaluating the ReDNet initiative. An evaluation questionnaire was designed and disseminated online to assess the various resources provided by ReDNet project; it had been online from April to July 2013, targeting professionals registered to ReDNet services. This phase also investigated the SMAIL service, a mobile application that was the latest technological tool developed by ReDNet team. Phase 3: promoting evidence based work in clinical practice through the preparation of four Technical Folders and two case reports. Technical Folders followed the methodology optimised during the ReDNet experience, organising NPS data under specific headings, measured for the need of health professionals. Case reports were collected in a Dual Diagnosis Unit in Italy ('Casa di Cura Parco dei Tigli'); assessed patients revealed for the first time the use of NPS; clinical interviews were conducted to collect a full anamnesis while for the first time psychopathological characteristics were measured in NPS abusers, using a psychometric instrument (MMPI-2). Results: In Phase 1 Italian services, in particular interviewees (n=243) from Departments of Psychiatry and Addiction, showed a strong interest for the subject but a poor understanding of NPS: 26.7% of respondents did not know if their patients ever used NPS; at the same time they considered this phenomenon as very relevant to their profession (e.g. psychomotor agitation [75.7%], errors in the assessment [75.7%], management of the clients [72%]); in addition less of a quarter of them had reliable information on new substances. Interviewees also reported the need for easily accessible channels of information to expand their expertise in the field (including emails [70%] and dedicated websites [51.9%]). The ReDNet initiative (Phase 2) reached professionals (n=270) from European countries and various other regions; they appreciated the website above all (48.5%), which provided access to other information (in form of academic papers, news, technical folders, etc.). The integration of technological-based and classic educational resources was used to self-educate professionals (52.6%) and supply information for research (33.7%) with up-to-date and 3 reliable information; in the same Phase the SMAIL service was analysed in its first 557 searches: in the pilot period 122 professionals used SMS inquiries (95%), asking information on NPS while highlighting the increasing number of NPS available on the market. Technical folders (Phase 3) described two new phenethylamines (Bromo-dragonfly and 25I-NBOMe), a novel ethno drug (Kratom) and a new synthetic cathinone (alpha-PVP) whose severe effects were also described in one of the clinical cases. The first case report (Alice) involved a clubber who used mephedrone and other NPS with a severe worsening of her psychiatric disturbances; the second one (Marvin) described a patient who was referred by a psychiatric service and revealed himself as a 'psychonaut' with an intense abuse of alpha-PVP. Conclusions: The exploration of the NPS galaxy is a new challenge for healthcare professionals. In this study, Italian services seemed to be unprepared to face the emergency and requested rapid access to reliable information; the ReDNet project provided both technology-based and traditional resources to expand knowledge on NPS, making professionals more aware of emerging issues and helping especially clinicians working in the field (e.g. via SMAIL service and Technical Folders). Overall, it can be observed that effective information services on NPS targeted at professionals initiatives should include an online interface integrating up-to-date information, describing NPS through specific Technical Folders and disseminating scientific literature; the use of technological tools, including mobile applications, is an important strategy to support health professionals in their activity. Finally, more 'visual' guidelines, possibly in the form of a 'map' of these heterogeneous compounds, could be a useful framework to describe NPS to physicians and other professionals who are often unprepared and unconfident to face such an expanding galaxy.
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Caractérisation de systèmes biologiques à l'échelle nanométrique : études des interactions entre des modèles membranaires et des agents exogènes / Characterization of biological systems at the nanoscale : study of the interaction between biomimetic membranes and exogenous agentsBeauvais, Estelle 15 October 2013 (has links)
Les membranes biologiques sont impliquées dans divers mécanismes comme la reconnaissance moléculaire ou encore la fusion membranaire. Les lipides, principaux composants des membranes, sont inhérents à ces processus cellulaires, mais leur organisation et leur rôle fonctionnel au sein de ces systèmes sont très complexes. Dans ce travail, nous avons utilisé des modèles membranaires mimant ces systèmes biologiques pour identifier les interactions mises en jeu avec divers agents exogènes (AEs), en utilisant la microscopie à force atomique (AFM). Nous avons donc travaillé sur deux AEs différents qui interagissent potentiellement avec ces membranes. Le premier intervient directement dans le cadre de l'étude du paludisme. Le mécanisme moléculaire de cette maladie (impliquant probablement des structures lipidiques) n'étant pas clair, la compréhension de celui-ci faciliterait le développement de nouvelles molécules antipaludiques et/ou cibles thérapeutiques. Parallèlement notre étude s'est portée sur l'interaction des nanoparticules (NPs) de TiO2, notre second AE, avec les membranes. Très utilisées dans l'industrie, ces NPs de TiO2 pourraient avoir un impact sur la santé humaine, en interagissant notamment avec les membranes cellulaires. Des techniques biophysiques classiques ont tout d'abord été utilisées pour évaluer l'interaction de l'AE avec des systèmes biomimétiques. Ensuite, lorsque celle-ci est prouvée, l'AFM est utilisée pour visualiser les changements morphologiques des modèles membranaires en présence de ces AEs. Ainsi, pour chaque AE, nous avons finalement suggéré un mécanisme d'interaction afin de répondre aux problématiques soulevées. / Biological membranes play a crucial role as a biological barrier but, paradoxically, they were involved in various precesses : as a molecular recognition, enzymatic catalysis, or membrane fusion. Lipids, as a main component of membranes, are entailed in these process but composition, organization, and functional role in these biological systems are quite complex. Here, we use lipid models mimicking biological membrane to identify their interaction mechanisms with various exogenous agents (EAs) like peptides, nanoparticules, drugs, proteins, using atomic force microscopy (AFM). In this project, we worked on two different molecules which interact potentially with biological membrane. The first one was a molecule directly implicated in malaria disease. In fact, the molecular mechanism, probably involving lipid membranes, is still unclear. The understanding of this mechanism would participate to find new antimalarial drug or new therapeutic targets. The second EA studied was titanium dioxide nanoparticules (TiO2 NPs). Widely used in industry, this product from nanotechnology's development could have an impact on human health, whose potential toxicity mechanism still unknown. Biophysical techniques such as fluorescence spectroscopy, Langmuir monolayer were used to evaluate the potential interaction of the EAs with biomimetic membranes. Then, when the interaction was proved, AFM was used in order to visualize the effects inferred by these EAs. Using supported lipid bilayers, we imaged their behavior after injection of the EA concerned, at the nanometer scale. For each EA, we could suggest a mechanism of interaction and respond to the issues raised.
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Factors Influencing the Net Promoter Score (NPS) : A Case of FunnelGadkari, Devesh January 2018 (has links)
Net Promoter Score (NPS) is considered to be an important metric for measuring customer loyalty. The concept is widely popular and adopted in several established and emerging industries. This master’s thesis work is aimed to spot the factors influencing the NPS of a company and the score rated by an individual. The study is conducted at a SaaS company, Funnel. Starting with the exploration of NPS in Funnel, the thesis work goes on to deep-dive in the journey of Funnel’s customers who responded to NPS. Each customer journey is presented as an individual case study. There are five such case-studies that represent five customers belonging to three distinct behavioural groups marked by NPS (Promoter, detractors and passives). The cases are analysed together with formulation of a revised framework of customer loyalty. The framework demonstrates factors that affect the customer loyalty, individual NPS response, and consequently the customer behaviour. It is noticed that customer satisfaction plays an important role in the individual response to NPS survey along with multiple other factors that influence the customer attitude and behaviour in different ways. It is also observed that the customer behaviour in the cases differs from the expected behaviour of promoters, detractors and passives proposed by NPS. The findings show that the loyalty behaviour could be manifested due to multiple industry-specific factors which are irrespective of company’s internal performance and satisfaction. Hence, the phenomenon of loyalty and satisfaction is addressed on an industry level. The analysis unfolds a theory that is demonstrated with a matrix to understand the impact of industry dynamic on satisfaction-loyalty relationship. This varying satisfaction-loyalty relationship calls for alterations in NPS practices as per the industry characteristics.
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Identification and classification of new psychoactive substances using Raman spectroscopy and chemometricsGuirguis, Amira January 2017 (has links)
The sheer number, continuous emergence, heterogeneity and wide chemical and structural diversity of New Psychoactive Substance (NPS) products are factors being exploited by illicit drug designers to obscure detection of these compounds. Despite the advances in analytical techniques currently used by forensic and toxicological scientists in order to enable the identification of NPS, the lack of a priori knowledge of sample content makes it very challenging to detect an 'unknown' substance. The work presented in this thesis serves as a proof-of-concept by combining similarity studies, Raman spectroscopy and chemometrics, underpinned by robust pre-processing methods for the identification of existing or newly emerging NPS. It demonstrates that the use of Raman spectroscopy, in conjunction with a 'representative' NPS Raman database and chemometric techniques, has the potential for rapidly and non-destructively classifying NPS according to their chemical scaffolds. The work also demonstrates the potential of indicating the purity in formulations typical of those purchased by end users of the product i.e. 'street-like' mixtures. Five models were developed, and three of these provided an insight into the identification and classification of NPS depending on their purity. These are: the 'NPS and non-NPS/benchtop' model, the 'NPS reference standards/handheld' model and the 'NPS and non-NPS/handheld' model. In the 'NPS and non-NPS/benchtop' model (laser λex = 785 nm), NPS internet samples were projected onto a PCA model derived from a Raman database comprising 'representative' NPSs and cutting agent/ adulterant reference standards. This proved the most successful in suggesting the likely chemical scaffolds for NPS present in samples bought from the internet. In the 'NPS reference standards/handheld' model (laser λex = 1064 nm), NPS reference standards were projected onto a PCA model derived from a Raman database comprising 'representative' NPSs. This was the most successful of the three models with respect to the accurate identification of pure NPS. This model suggested chemical scaffolds in 89% of samples compared to 76% obtained with the benchtop instrument, which generally had higher fluorescent backgrounds. In the 'NPS and non-NPS/handheld' model (laser λex = 1064 nm), NPS internet samples were projected onto a PCA model derived from a Raman database comprising 'representative' NPSs and cutting agent/ adulterant reference standards. This was the most successful in differentiating between NPS internet samples dependent on their purity. In all models, the main challenges for identification of NPS were spectra displaying high fluorescent backgrounds and low purity profiles. The 'first pass' matching identification of NPS internet samples on a handheld platform was improved to ~50% using a laser source of 1064 nm because of a reduction in fluorescence at this wavelength. We outline limitations in using a handheld platform that may have added to problems with appropriate identification of NPS in complex mixtures. However, the developed models enabled the appropriate selection of Raman signals crucial for identification of NPS via data reduction, and the extraction of important patterns from noisy and/or corrupt data. The models constitute a significant contribution in this field with respect to suggesting the likely chemical scaffold of an 'unknown' molecule. This insight may accelerate the screening of newly emerging NPS in complex matrices by assigning them to: a structurally similar known molecule (supercluster/ cluster); or a substance from the same EMCDDA/EDND class of known compounds. Critical challenges in instrumentation, chemometrics, and the complexity of samples have been identified and described. As a result, future work should focus on: optimising the pre-processing of Raman data collected with a handheld platform and a 1064 nm laser λex; and optimising the 'representative' database by including other properties and descriptors of existing NPS.
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"Particularly New Mexico's Monument": Place-Making at Fort Union, 1929-2014January 2016 (has links)
abstract: This dissertation examines the conception, planning, creation, and management of Fort Union National Monument (FOUN) in northeastern New Mexico. Over approximately the last eighty-five years, writers, bureaucrats, boosters, and the National Park Service (NPS) have all been engaged in several different kinds of place-making at FOUN: the development of a written historical narrative about what kind of place Fort Union was (and is); the construction of a physical site; and the accompanying interpretive guidance for experiencing it.
All of these place-making efforts make claims about why Fort Union is a place worthy of commemoration, its historical significance, and its relationship to local, regional, national and international contexts. The creation and evolution of Fort Union National Monument as a memorial landscape and a place for communion with an imagined past—in short, a site of memory and public history—is only the latest chapter in a long history of migration, conflict, shifting ownership, and land use at that site. I examine the evolution of a sense of place at Fort Union in two broad time periods: the twenty-five years leading up to the monument’s establishment, and the seven decades of NPS management after it was created.
Taken as a case study, the story of FOUN raises a number of questions about the basic mission and meaning of NPS as a cultural institution and educational organization; how the agency conceptualizes and “talks about” Native Americans and the Indian Wars; the history and practice of public history; and how best to address sites like Fort Union that seek to historicize America’s imperial past. / Dissertation/Thesis / Doctoral Dissertation History 2016
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