Access to abstract permanently restricted to Ball State community only. / Access to thesis permanently restricted to Ball State community only. / School of Physical Education, Sport, and Exercise Science

Sammanfattning Introduktion: I dagens arbetsliv och samhälle har individen blivit allt mer stillasittande och minskat mängden motion med risk för sämre kondition trots att detta är en känd riskfaktor för sjukdom och nedsatt arbetsförmåga. Syftet med denna studie var att studera konditionsnivån hos kontorsanställda i förhållande till BMI, kön och ålder. Metod: En kvantitativ tvärsnittsstudie har genomförts baserad på data från hälsoundersökning där BMI, kön, ålder och konditionstal undersöktes. 100 personer deltog i studien, varav 33 kvinnor och 67 män i åldern 25-63 år. Resultat: De kontorsanställda hade en god syreupptagningsförmåga på i genomsnitt 37,3 ml/(kg x min) och låg över det rekommenderade konditionstalet 35 ml/(kg x min) för kontorsarbetare. Kvinnorna i gruppen hade bättre konditionstal än männen. Medelålders kvinnor (41-50 år) hade något lägre konditionstal än yngre (25-40 år)och äldre kvinnor (51-63 år). Männen med högt BMI hade ett sämre konditionstal än dem med ett lägre BMI. Konklusion: Trots stillasittande arbete hade de kontorsanställda en god kondition och det ger förutsättningar att prestera ett bra resultat i arbetet. Kvinnorna hade ett bättre konditionstal än männen och högre BMI förknippades med lägre konditionstal. Företagssköterskan och företagshälsovården kan spela en viktig roll för att medverka till förbättrad kondition och lägre vikt bland anställda, vilket skulle gynna hälsan och arbetsförmågan. Nyckelord: BMI, konditionstal, kontorsanställda, syreupptagningsförmåga och ålder. / Summary Introduction: In modern working life and society, individual have become more and more sedentary and physical activity has decreased affecting the fitness level. This has occurred despite the common knowledge that a sedentary lifestyle is a risk factor associated with illness and decreased ability to work. The aim of the study was to study the fitness level of office workers in relation to BMI, sex, and gender. Method: A quantitative cross-sectional study has been done which included data from health checks including BMI, gender, age, and capacity of absorption of oxygen, which was expressed as fitness level (1-5). One hundred office workers participated in the study, 33 females and 67 males aged 25-63 years. Result: The office employees had a good capacity of absorption of oxygen, on average 37.3 ml/(kg x min), which was over the recommended fitness level 35 ml/(kg x min) for office employees. The females had a better fitness level than the males. Middle aged (41-50 years) women had somewhat lower fitness level than younger (25-40 years) and older (51-63 years)females. Men with high BMI had a lower fitness level than men with low BMI. Conclusion: The office employees had a good fitness level in spite of sedentary work and this gives conditions of performing well at work. The females had a better fitness level than the males and higher BMI was associated with lower fitness level. The company nurse and the occupational health service may play an important role in contributing to better fitness level and lower weight among office employees, which would promote health and working capacity. Keywords: Age, BMI, fitness level, office employees and oxygen uptake.

Chitosan membrane has found applications in biomedical, wastewater treatment, and petrochemical fields that involve the use of silver ions (Ag+). However, mobility of Ag+ in chitosan membranes has seldom been studied. In this study, transport properties of Ag+ in chitosan membranes are studied in-depth, to determine diffusivity coefficient, permeability coefficient, and sorption uptake of Ag+ in chitosan. All parameters are evaluated based on the influence of feed concentration, membrane thickness and operating temperature. The diffusivity is determined from the time lag obtained from transient diffusion experiments. The permeability is determined from the steady state of permeation experimentally. The diffusivity and corresponding permeability coefficients of Ag+ in chitosan range from to 2.0 10-7 (cm2/s) and from 6.6 10-8 to 2.0 10-7 {mol m/[m2 s (mol/L)]}, respectively, over the conditions tested. Temperature dependencies of these two parameters are found to follow the Arrhenius relationship. Sorption uptake of the silver salt in chitosan correlates well with the Langmuir isotherm. Also determined from the sorption tests are degree of membrane swelling at different concentrations. This information allows diffusivity coefficients to be determined from the steady state permeation rate. These values of diffusivity are compared with that obtained using the time lag method.

Short interfering RNAs (siRNAs) are 21-23 nucleotide-long double-stranded RNA molecules that can trigger the RNA interference (RNAi). RNAi is a post-transcriptional gene silencing process whereby siRNAs induce the sequence-specific degradation of complementary messenger RNA (mRNA). Despite their promising therapeutic capabilities, siRNA-based strategies suffer from enzymatic degradation and poor cellular uptake. Several carrier-based approaches have been employed to enhance the stability and efficiency of siRNA delivery. Considering their safety, efficiency, and targeting capabilities, peptide-based delivery systems have shown great promise for overcoming the main obstacles in siRNA therapeutic delivery. Peptides are versatile and easily designed to incorporate a number of specific attributes required for efficient siRNA delivery. This thesis focuses on the design, characterization and utilization of a new class of amphipathic peptides for siRNA delivery. The study includes: (i) designing amphipathic, amino acid pairing peptide sequences for siRNA delivery, (ii) siRNA delivery experiments in vitro to evaluate transfection efficacy of the designed peptides, (iii) physicochemical characterization of the interaction between promising peptides and siRNA, and (iv) identifying internalization pathway and kinetics of a promising peptide, C6M1. The peptide C6, an 18-mer amphipathic, amino acid pairing peptide, was designed as an siRNA delivery carrier by incorporating three types of amino acids, i.e., arginine, leucine, and tryptophan. This peptide adopted a helical structure upon co-assembling with siRNA. The C6-siRNA co-assembly showed a size distribution between 50 and 250 nm, confirmed by dynamic light scattering and atomic force microscopy. The C6-siRNA interaction enthalpy and stoichiometry were 8.8 kJ.mol-1 and 6.5, respectively, obtained by isothermal titration calorimetry. A minimum C6:siRNA molar ratio of 10:1 was required to form stable co-assemblies/complexes, indicated by agarose gel shift assay and fluorescence spectroscopy. C6 showed lower toxicity and higher efficiency in cellular uptake of siRNA, compared with Lipofectamine 2000, a lipid-based positive control. Fluorescence microscopy images confirmed the localization of C6-siRNA complexes in the cytoplasm. In order to enhance the solubility and delivery efficiency further, a modified peptide, C6M1, was designed by replacing three leucine with tryptophan residues in the C6 sequence. The fluorescence assay confirmed that the sequence mutation significantly increased the solubility of C6M1. C6M1 adapted a stable helical structure in saline or upon interaction with siRNA. The toxicity assay showed lower toxicity of C6M1 with an IC50 (the concentration of peptide at 50% cell viability) of 22 ??M, compared with C6 with that of 12 ??M. Naked siRNA was completely degraded after 4 h incubation in 50% serum, while the siRNA in complex with C6M1 was preserved even after 24 h. Western blotting showed a significant decrease in GAPDH protein contents (75%) in CHO-K1 Chinese hamster ovary cells, 48 h after treatment with C6M1-GAPDH siRNA complexes. The interaction of C6M1-siRNA complexes with cell surface and the mechanisms involved in the internalization of the complex in different size ranges were studied. Heparin and chlorate treatments revealed that the electrostatic interaction of the C6M1-siRNA complex with heparan sulphate proteoglycans at the cell surface is required to trigger the uptake process. Using endocytic inhibitors, it was found that small C6M1-siRNA complexes (mean ~155 nm) mainly enter CHO-K1 cells through an energy-independent mechanism, most likely involving direct translocation. In contrast, large complexes (mean ~460 nm) internalize the cells mainly through a lipid raft-dependant macropinocytosis. The integrity of the cytoskeletal components also showed significant impact on the efficient internalization of the C6M1-siRNA complex. The kinetics experiments confirmed the fast internalization of small complexes (with uptake half-time of 25 min) in comparison to large complexes (70 min). This work provides essential information for peptide design and characterization in the development of amphipathic peptide-based siRNA delivery.

The feedbacks among aerosols, clouds, and radiation are important components for understanding Earth's climate system and quantifying human-induced climate change, yet the magnitude of these feedbacks remain highly uncertain. Since every cloud droplet in the atmosphere begins with water condensing on a pre-existing aerosol particle, characterizing the ability of aerosols to uptake water vapor and form cloud condensation nuclei (CCN) are key to understanding the microphysics behind cloud formation, as well as assess the impact aerosols have on the Earth system. Through a combination of controlled laboratory experiments and field measurements, this thesis characterizes the ability of atmospheric aerosols to uptake water vapor and become CCN at controlled levels of water vapor supersaturation. The origin of the particle water uptake, termed hygroscopicity, is also explored, being from either the presence of deliquescent soluble material and/or adsorption onto insoluble surfaces. The data collected and presented is comprehensive and includes (1) ground samples of volcanic ash, collected from six recent eruptions re-suspended in the laboratory for analysis, (2) laboratory chamber and flow-tube studies on the oxidation and uptake of surface active organic compounds, and (3) in-situ aircraft measurements of aerosols from the Arctic background, Canadian boreal forests, fresh and aged biomass burning, anthropogenic industrial pollution, and from within tropical cyclones in the Atlantic basin. Having a more thorough understanding of aerosol water uptake will enable more accurate representation of cloud droplet number concentrations in global models, which can have important implications on reducing the uncertainty of aerosol-cloud-climate interactions, as well as additional uncertainties in aerosol transport, atmospheric lifetime, and impact on storm dynamics.

<p>The rapidly increasing use of silver nanoparticles (Ag NPs) in consumer products and medical applications has raised ecological and human health concerns. Significant progress has been made in understanding the toxicity of silver nanoparticles (Ag NPs) under carefully controlled laboratory conditions. The goals of this dissertation were to investigate the mechanism of Ag NP toxicity under both laboratory conditions and environmental backgrounds, using <italic>Caenorhabditis elegans</italic> (<italic>C. elegans</italic>) as a model system. A key question for addressing these concerns is whether Ag NP toxicity is mechanistically unique to nanoparticulate silver or if it is a result of the release of silver ions. Ag NPs are produced in a large variety of monomer sizes and coatings, and since their physicochemical behavior depends on the media composition, it is important to understand how these variables modulate toxicity.</p><p> In order to test the hypothesis of a particle-specific effect, multiple techniques were used, including analytical chemistry, pharmacological rescue, and genetic analysis. Results suggested that dissolution was important for all tested Ag NPs and oxidative stress (a particle-specific effect) was important only for some Ag NPs, especially the citrate-coated Ag NPs (CIT-Ag NPs). The hypothesis of the particle-specific effect was further tested by investigating the cellular uptake and damage co-localization upon exposures to CIT-Ag NPs. I found that Ag NPs crossed all layers, including the pharynx, gut, and also embryos through trans-generational transfer. Sites of damage were examined through transmission electron microscopy (TEM), and CIT-Ag NPs showed a more severe and deeper level of damage compared to ionic Ag. In addition, pharmacological inhibitors in parallel with genetic mutants (deficient in both endocytosis and lysosomal function) were used to explore the impact of those pathways on Ag NP uptake and associated toxicity. I found that endocytosis was important for CIT-Ag NP uptake and toxicity. Most intriguingly, one of the lysosomal deficient mutants was much more sensitive than wild type to reproductive inhibition after exposure to CIT-Ag NPs but not ionic Ag, constituting a clear nanoparticle-specific toxic effect.</p><p> These laboratory mechanistic studies, however, cannot be directly extrapolated to complicated environmental conditions, including variable amounts of natural organic matter (NOM), different temperatures and salinities, surface sulfidation, etc. My general hypothesis was that complex environmental medium would reduce Ag NP toxicity. In support of this, the environmental conditions present in mesocosms resulted in a loss of toxicity one week after dosing/spiking. In laboratory studies, I found that that increasing temperature and salinity tended to increase Ag NP toxicity, while sulfidation reduced Ag NP toxicity, acting as a &ldquonatural antidote&rdquo. I studied two types of NOM, Suwannee River and Pony Lake fulvic acids (SRFA and PLFA respectively). PLFA rescued toxicity more effectively than SRFA. Therefore, CIT-Ag NP-NOM interactions were explored in depth using PLFA. Using hyperspectral dark field microscopy, I was able to detect the formation of Ag NP-PLFA complexes and the limited tissue uptake of Ag NPs (with and without PLFA). Consistent with the reduced acute toxicity of Ag NPs by PLFA, I also found a rescue effect of PLFA on Ag NP-induced ultrastructural damage.</p><p> In conclusion, Ag NP toxicity resulted largely from dissolution and in some cases also from a particle-specific effect. However, Ag NP toxicity was strongly altered by environmental matrices. Continued in depth elucidation of Ag NP behavior, cellular uptake pathways and trafficking, and their interactions with other environmental factors will be invaluable in predicting, designing, and remediating the potential/existing environmental implications of silver-related nanotechnology.</p> / Dissertation

Syfte och frågeställningar Syftet med den här studien var att undersöka den aeroba fysiska aktivitetsnivån hos gymnasieungdomar på Bygg- och anläggningsprogrammet under skoldagar som innehöll teorilektioner, praktiska lektioner, idrottslektioner och raster. Frågan som ställdes var: Hur ser den fysiska aktivitetsnivån ut under teorilektioner, praktiska lektioner och lektioner i idrott och hälsa samt under raster hos gymnasieelever på Bygg- och anläggningsprogrammet. Metod I studien deltog 9 pojkar i åldern 16 år, längd 174-192cm och vikt 51-91kg. Den test som genomförts är 5 Minuters Pyramid Test (5MPT) och registrering av aerob fysisk belastning gjordes med hjärtfrekvensmätningar. 5MPT är ett skytteltest som är fem minuter långt, där försökspersonen tar sig fram och tillbaka mellan två stolpar och så snabbt som möjligt passerarfram och tillbaka över en vertikal pyramidformad trappramp (sträcka 5,5 meter). Antalet vändor, skattad ansträngning samt hjärtfrekvens (HF) registrerades. Utvecklad power (effekt) erhölls genom produkten av kroppsmassa, gravitation, antal vändor, höjd på högsta plinten (0,53 m) dividerat med total tiden i 5MPT. Utifrån 5MPT kunde beräknad VO2 max samt Power/kg (W/kg) beräknas för försökspersonen. Testet med hjärtfrekvensregistrering gick till så att eleverna under en skolvecka hela skoldagen bar en pulsklocka med förtejpad urtavla och ett elektrodbälte. De tryckte på händelsemarkering vid rast och när lektionen startade igen. Eleverna förde dagbok där de beskrev vad de gjort under dagen.  Resultat För samtliga försökspersoner kan man se en genomgående trend avseende fysisk belastningsnivå uttryckt som hjärtfrekvens vilket syns i följande resultat. Den högsta pulsen uppnåddes under idrottslektionerna med en genomsnittlig hjärtfrekvens på ca 140 slag/min, den näst högsta under de praktiska lektionerna med 94 slag/min. Därnäst följde rasterna med 83 slag/min och lägst utslag visades under teorilektionerna med en genomsnittlig hjärtfrekvens på ca 80 slag/min. Försökspersonerna utnyttjade ca 30 % av sin maximala syreupptagningsförmåga under de praktiska lektionerna. Slutsats Den här studien har visat att det är under undervisningen i idrott och hälsa och delvis på de praktiska lektionerna som en högre aktivitetsnivå mätt i hjärtfrekvens kan noteras hos försökspersonerna. Studien indikerar också att försökspersonerna utsätts för relativt hög fysisk belastning. Ca 30 % av den maximala syreupptagningsförmågan utnyttjas vid en skoldag med praktiska lektioner. / Aim The aim of the study was to investigate the aerobic physical activity level of high school students who study to become building workers during school days which consist of theory classes, practical classes, physical education classes and pauses. The question to be answered was: How was the aerobic physical activity level during theory classes, practical classes, physical education classes and pauses for high school students in a program for building workers. Method In this study participated 9 boys aged 16, length 174-192 cm and weight 51-91 kg. The test that has been carried out was 5 Minutes Pyramid Test (5MPT). In addition heart rate was measured during the school day. The 5MPT is a 5-minute-shuttle test, in which the participant moves back and forth in a short interval (5.5 m) over boxes (highest height 0.53 m) formed like a pyramid. Power in the pyramid test (5MPT POWER) was calculated as the product of numbers of laps, body mass, gravity and highest box level divided by time. From 5 MPT VO2 max and Power/kg (W/kg) were calculated for the participants. The participant’s heart rates were measured during a week the whole school day by means of a heart monitor with the monitor display taped over and an electrode belt. They pushed a button on the clock to mark when they had pauses and when the classes started again. The participants wrote in a diary what they had done during each day. Results The results show that for each of the participants the same trend considering aerobic physical load level expressed in heart rate in the following results. The highest pulse rate was obtained during the physical education lessons 140 beats/min followed by practical lessons 94 beats/min, pauses 83 beats/min and theory lessons 80 beats/min. The participants are using approximately 30 % of their maximal oxygen uptake during a day with practical lessons. Conclusions This study shows that it is during physical education lessons and to some extent during practical lessons in building construction, a higher activity level measured in heart rate can be noticed in the participants. The study indicates that the participants are exposed to a relative high physical workload. Roughly 30 % of maximal oxygen uptake is used during a day of practical lessons.

This study was conducted in Esquimalt lagoon, located southwest of Victoria, British Columbia, Canada. Physical characteristics of the water column, e.g. circulation and stratification, changed seasonally resulting from variations in tides, temperature, precipitation and wind. Chemical characteristics, e.g. oxygen and dissolved nutrient concentrations, also differed temporally relative to those in the lagoon’s ocean source water (Juan de Fuca Strait) because of variations in local photosynthesis and nutrient use by phytoplankton. Diatom blooms occurred in the spring, and blooms of photosynthetic flagellates (Heterosigma akashiwo (2009) and Akashiwo sanguinea (2009 and 2010)) occurred in the late summer and early fall when nitrate, ammonium, and urea were depleted. Proliferation of these flagellates led to the development of harmful algal blooms (HABs) associated with oxygen depletion in the lagoon bottom waters. Increased oxygen demand from bacterial degradation of algal biomass and exudates was the likely cause for bottom water hypoxia under reduced tidal exchange. / Graduate

Tyrimų tikslas – naudojant kvantinius taškus (KT), kaip tinkamų vaistų pernašai biosuderinamų nanodalelių modelį, in vitro nustatyti bendrus tikslingai nemodifikuotų nanodalelių patekimo į ląsteles ir lokalizacijos jose dėsningumus. Spektroskopiniais metodais ištyrus KT patekimo į ląsteles laikinę dinamiką nustatyta, kad neigiamo krūvio apvalkalo KT patekimo į ląsteles procesą galima suskirstyti į tris etapus, tačiau šie kaupimosi etapai skirtingose ląstelių kultūrose yra nevienodos trukmės. Konfokalinės fluorescencijos mikroskopijos metodu ištyrus neigiamo paviršiaus krūvio KT patekimo į ląsteles procesą, pagal viduląstelinį KT pasiskirstymą ir susiformavusių pūslelių tipus, galima suskirstyti į keturias fazes. Naudojant fluorescencijos gyvavimo trukmės vaizdinimo mikroskopijos metodą užregistruotas nuo endosomų brandos priklausantis viduląstelinių vezikulių vidinės struktūros heterogeniškumas. Skirtingos brandos endosomos gali būti apibūdinamos ir vaizdinamos remiantis jose sukauptų KT savitomis fotoliuminescencijos gyvavimo trukmėmis. Skirtingais fizikiniais ir biocheminiais metodais nustatyta, kad difuzijos būdu KT per ląstelės membraną neprasiskverbia, bet į ląsteles patenka endocitozės būdu. Nepadengti baltymais neigiamo paviršiaus krūvio KT į ląsteles patenka tik vienu nuo kaveolino priklausančiu endocitozės keliu. KT, kaip modelinių diagnostinių priemonių, ir antivėžinio preparato bendras panaudojimas in vitro atskleidė, kad KT, nesukeldami toksinio poveikio ląstelių... [toliau žr. visą tekstą] / The overall aim of the study is to identify the general rules for intracellular uptake and localisation of non-targeted nanoparticles by employing colloid quantum dots (QDs) as a model of biocompatible nanoparticle-based drug carriers. The investigation of intracellular uptake of non-targeted negatively charged QDs with fluorescence spectroscopy method revealed three time-related accumulation stages, which are characteristic for all investigated cell lines, but the stages were of different timing for each of the investigated cell line. The confocal fluorescence microscopy imaging showed four intracellular accumulation phases of QDs based on type and localisation of formed vesicles. The fluorescence lifetime imaging microscopy revealed the inner heterogeneity of intracellular vesicles: the endosomes at particular stage of maturity can be identified by different photoluminescence lifetimes of accumulated QDs. QDs do not penetrate plasma membranes through passive diffusion, but enter a cell through endocytosis. Negatively charged QDs without protein corona enter the cells through the single, caveolin-dependent endocytic pathway. Examination of the possibility to combine QDs, as model diagnostic probes, with anticancer agent in vitro revealed, that despite QDs alone had no cytotoxic effects on cells viability, they increased drug resistance. Therefore, this effect needs profound further research before the application of quantum dots in combined diagnosis and therapy in vivo.

The overall aim of the study is to identify the general rules for intracellular uptake and localisation of non-targeted nanoparticles by employing colloid quantum dots (QDs) as a model of biocompatible nanoparticle-based drug carriers. The investigation of intracellular uptake of non-targeted negatively charged QDs with fluorescence spectroscopy method revealed three time-related accumulation stages, which are characteristic for all investigated cell lines, but the stages were of different timing for each of the investigated cell line. The confocal fluorescence microscopy imaging showed four intracellular accumulation phases of QDs based on type and localisation of formed vesicles. The fluorescence lifetime imaging microscopy revealed the inner heterogeneity of intracellular vesicles: the endosomes at particular stage of maturity can be identified by different photoluminescence lifetimes of accumulated QDs. QDs do not penetrate plasma membranes through passive diffusion, but enter a cell through endocytosis. Negatively charged QDs without protein corona enter the cells through the single, caveolin-dependent endocytic pathway. Examination of the possibility to combine QDs, as model diagnostic probes, with anticancer agent in vitro revealed, that despite QDs alone had no cytotoxic effects on cells viability, they increased drug resistance. Therefore, this effect needs profound further research before the application of quantum dots in combined diagnosis and therapy in vivo. / Tyrimų tikslas – naudojant kvantinius taškus (KT), kaip tinkamų vaistų pernašai biosuderinamų nanodalelių modelį, in vitro nustatyti bendrus tikslingai nemodifikuotų nanodalelių patekimo į ląsteles ir lokalizacijos jose dėsningumus. Spektroskopiniais metodais ištyrus KT patekimo į ląsteles laikinę dinamiką nustatyta, kad neigiamo krūvio apvalkalo KT patekimo į ląsteles procesą galima suskirstyti į tris etapus, tačiau šie kaupimosi etapai skirtingose ląstelių kultūrose yra nevienodos trukmės. Konfokalinės fluorescencijos mikroskopijos metodu ištyrus neigiamo paviršiaus krūvio KT patekimo į ląsteles procesą, pagal viduląstelinį KT pasiskirstymą ir susiformavusių pūslelių tipus, galima suskirstyti į keturias fazes. Naudojant fluorescencijos gyvavimo trukmės vaizdinimo mikroskopijos metodą užregistruotas nuo endosomų brandos priklausantis viduląstelinių vezikulių vidinės struktūros heterogeniškumas. Skirtingos brandos endosomos gali būti apibūdinamos ir vaizdinamos remiantis jose sukauptų KT savitomis fotoliuminescencijos gyvavimo trukmėmis. Skirtingais fizikiniais ir biocheminiais metodais nustatyta, kad difuzijos būdu KT per ląstelės membraną neprasiskverbia, bet į ląsteles patenka endocitozės būdu. Nepadengti baltymais neigiamo paviršiaus krūvio KT į ląsteles patenka tik vienu nuo kaveolino priklausančiu endocitozės keliu. KT, kaip modelinių diagnostinių priemonių, ir antivėžinio preparato bendras panaudojimas in vitro atskleidė, kad KT, nesukeldami toksinio poveikio ląstelių... [toliau žr. visą tekstą]