Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease of motor neurons characterized by muscle paralysis and death within 3-5 years of onset. However, due to unknown mechanisms, the extraocular muscles (EOMs) remain remarkably unaffected. The EOMs are highly specialized muscles that differ from other muscles in many respects, including innervation and satellite cells (SCs). Understanding whether these factors play a role in the relative sparing of EOMs in ALS could provide useful clues on how to slow down the progression of ALS in other muscles. The EOMs and limb muscles from terminal ALS patients and age-matched controls as well as the commonly used SOD1G93A ALS mouse model were studied with immunofluorescence. Antibodies against neurofilament and synaptophysin were used to identify nerves and neuromuscular junctions (NMJs); against Pax7, NCAM, MyoD, myogenin, Ki-67, dystrophin and laminin, to identify SCs and their progeny in EOMs and limb muscles. The proportion and fiber size of myofibers containing myosin heavy chain (MyHC) slow tonic and MyHC slow twitch were also determined in human EOMs. The abundance of SCs differed extensively along the length of control human EOMs, being twice as abundant in the anterior portion. Pax7-positive cells were also detected in non-traditional SC positions. EOMs from terminal ALS patients showed similar numbers of resting and activated SCs as the controls. In limb muscles of ALS patients, the number of resting and activated SCs ranged from low (similar to normal aged, sedentary individuals) to high numbers, especially in muscles with long duration of disease and varied between the upper and lower limbs. The EOMs maintained a high degree of innervation compared to hindlimb muscles of symptomatic SOD1G93A mice. MyHC slow tonic fibers were less abundant in ALS patients than in controls. The change seemed more pronounced in bulbar onset patients, and in this group of subjects only, there was a strong association between decline in MyHC slow tonic fibers and age of death. Notably, the decline in MyHC slow tonic fibers was unrelated to disease duration. Our data suggested that SCs play a minor role in the progression of ALS in general and in the sparing of the EOMs in particular. The generally preserved innervation in the EOMs of G93A mice may reflect distinct intrinsic properties relevant for sparing of the oculomotor system.  Even though the EOMs are relatively spared in ALS, MyHC slow tonic myofibers were selectively affected and this may reflect differences in innervation, as these fibers are multiply innervated. / Amyotrofisk lateralskleros (ALS) är en obotlig neurodegenerativ sjukdom som främst påverkar kroppens viljestyrda motoriska nervceller. ALS leder till förlamning, muskelförtvining och slutligen döden genom andningssvikt, vanligen inom tre till fem år efter sjukdomsdebuten. Av okända anledningar så bibehålls ögonmusklernas funktion mycket bättre vid ALS i jämförelse med andra muskler och är hos merparten av patienter i stort sett opåverkade. Ögonmusklerna är mycket specialiserade muskler som skiljer sig från andra muskler i kroppen på flera sätt, bland annat genom deras unika nervförsörjning och genom de satellitceller – muskelspecifika stamceller, som finns i dem. En ökad förståelse för hur dessa faktorer inverkar på ögonmusklernas motståndskraft vid ALS skulle kunna ge värdefulla ledtrådar till hur man skulle kunna sakta ned sjukdomens fortskridande i andra muskler vid ALS. Ögonmuskler och extremitetsmuskler från avlidna ALS-patienter och åldersmatchade friska kontroller, tillsammans med transgena möss med den sjukdomsalstrande mutationen SOD1G93A, studerades genom immunfluorescens och efterföljande mikroskopering. Antikroppar mot molekylerna Pax7, NCAM, MyoD, myogenin, Ki-67, laminin och dystrofin användes för att identifiera satellitceller och deras dotterceller i ögonmuskler och extremitetsmuskler. Antikroppar mot neurofilament och synaptofysin användes för att identifiera nerver och neuromuskulära synapser hos transgena SOD1-möss. Antikroppar mot toniska (tonic) och ryckande (twitch) muskelmyosinkedjor användes för att bestämma proportionen av och storleken på dessa typer av muskelfibrer i ögonmuskler från avlidna ALS-patienter och friska kontroller. Mängden satellitceller varierade mellan de främre och de mer bakre delarna i friska, humana ögonmuskler och var dubbelt så många i den främre delen av muskeln jämfört med den mellersta och bakre delen av muskeln. Celler som uttryckte satellitcellsmarkören Pax7 hittades även i icke-traditionella satellitcellspositioner i ögonmusklerna. Mängden satellitceller i ögonmusklerna från ALS-patienter var samma som hos friska kontroller. I extremitetsmusklerna hos ALS-patienter varierade mängden satellitceller mellan låga nivåer (liknande de hos friska åldrade, inaktiva individer) till höga nivåer, särskilt i muskler där sjukdomen fortskridit under lång tid. Dessutom varierade mängden satellitceller mellan övre och nedre extremiteter. Hos symptomatiska SOD1G93A-möss hade ögonmusklerna en mycket välbevarad innervation jämfört med bakbensmusklerna, där många neuromuskulära synapser saknade kontakt mellan nerven och motorändplattan. Proportionen muskelfibrer med toniska muskelmyosinkedjor var lägre hos ALS-patienter jämfört med friska kontroller. Denna minskning var tydligare hos patienter där sjukdomssymtomen hade debuterat i tugg- och ansiktsmuskulaturen – så kallad bulbär ALS. Dessutom fanns det i den här gruppen, men ingen annan studerad grupp, en stark korrelation mellan nedgången i toniska fibrer och patientens ålder. Värt att notera är att minskningen av toniska muskelfibrer saknade korrelation med hur länge patienten hade varit sjuk i ALS. Den generellt välbevarade innervationen i ögonmusklerna hos SOD1G93A-möss kan spegla distinkta inneboende egenskaper hos ögonmusklerna som är av vikt för bevarandet av ögonrörligheten vid ALS. Gällande satellitceller så antyder våra data att satellitceller och deras regenerativa kapacitet spelar en försumbar roll vid ALS i allmänhet och vid ögonmusklernas bevarande i synnerhet. Slutligen, även om ögonmuskler generellt är välbevarade vid ALS så är toniska muskelfibrer märkbart påverkade och detta kan spegla skillnader mellan olika nervcellsgruppers känslighet vid ALS.

We give an overview of quantum chemical methods with a particular emphasis on the development of high-accuracy quantum chemical models. The reliability of these methods often hinges on whether enough electron correlation is included in the truncated wave function. As an example, we investigate the structures of m-benzyne and its fluorinated derivative, tetrafluoro-m-benzyne where the inclusion of triple excitations is paramount to correctly describe through-bond delocalization of the monocyclic form. At the CCSDT/6-31G** level of theory, the C1–C3 distance of the minimum energy form of m-benzyne is 2.0°A and the profile of the PES along the C1–C3 distance is that of an asymmetric, single-well, in agreement with previous density-functional theory and coupled cluster studies. In addition, the calculated CCSD(T) fundamental frequencies are in excellent agreement with the measured infrared frequencies, thus confirming the monocyclic form of m-benzyne. For tetrafluoro-m-benzyne, however, the increased eclipsing strain between the ring-external Câ X bonds stabilizes the bicyclo[3.1.0]hexatriene form: the C1–C3 distance is calculated at the CCSD(T)/cc-pVTZ level to be approximately 1.75 °A, which is in the range of elongated CC bonds. Computed harmonic vibrational frequencies compare reasonably well with the experimental neon-matrix difference spectrum and provide further evidence for the existence of a bicyclic form. We also report an extension of the coupled cluster iterative-triples model, CC3, to excited states of open-shell molecules, including radicals. We define the method for both spin-unrestricted Hartree-Fock (UHF) and spin-restricted open-shell Hartree-Fock (ROHF) reference determinants and discuss its efficient implementation in the PSI3 program package. The program is streamlined to use at most O(N7) computational steps and avoids storage of the triple-excitation amplitudes for both the ground-and excited-state calculations. The excitation-energy program makes use of a Lowdin projection formalism (comparable to that of earlier implementations) that allows computational reduction of the Davidson algorithm to only the single- and double-excitation space, but limits the calculation to only one excited state at a time. However, a root-following algorithm may be used to compute energies for multiple states of the same symmetry. Benchmark applications of the new methods to the lowest valence 2B1 state of the allyl radical, low-lying states of the CH and CO+ diatomics, and the nitromethyl radical show substantial improvement over ROHF- and UHF-based CCSD excitation energies for states with strong double-excitation character or cases suffering from significant spin contamination. For the allyl radical, CC3 adiabatic excitation energies differ from experiment by less than 0.02 eV, while for the 2§+ state of CH, significant errors of more than 0.4 eV remain. Finally, ground- and excited-state dipole moments are derived diagramatically and were recently developed within the PSI3 quantum chemistry package. However, convergence problems with computing the left-hand excited-state has prevented us from reporting any meaningful results. Thus, future work includes solving this convergence problem before the effects of triple excitations on one-electron properties can be reported with certainty. / Ph. D.

The following thesis focuses on two areas of chemistry, pi-pi interactions and radical cation dimers. Approximations to the exact solution to the Schrodinger equation are investigated for these types of chemical systems with a variety of theoretical methods. The first chapter provides an introduction to the various quatum mechanical methods used in this research. The second chapter focuses specifically on pi-pi interaction. In this chapter, high quality quantum mechanical methods are used to examine how substituents tune pi-pi interactions between monosubstituted benzene dimers in parallel-displaced geometries. In addition, the role of dispersion and coulombic interactions in these systems is investigated to determine the nature of the substituent effect. In the third chapter radical cation dimers are investigated. Benchmark results with full configuration interaction (FCI) and equation-of-motion coupled-cluster for ionized systems (EOM-IP-CCSD) are presented for prototypical charge transfer species. Conclusions regarding chapters 2 and 3 are presented in the final chapter. This work may form the basis for improved approaches to rational drug design, organic optical materials, and molecular electronics.

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This study investigated characteristics of algal organic matter (AOM) derived from four species (cyanobacteria Microcystis aeruginosa and Merismopedia tenuissima, diatom Fragilaria crotonensis and green alga Chlamydomonas geitleri) dominating phytoplanktonic populations in the reservoirs supplying drinking water treatment plants - the water reservoirs Švihov (the Želivka water treatment plant) and Josefův Důl (the Jizerské Mountains), Czech Republic. The four mentioned microorganisms were cultivated under laboratory conditions and the algal growth was quantified by a number of cells, chrorophyll-a and optical density. Production of AOM was evaluated by dissolved organic carbon concentration measurements, by specific UV absorbance, the amount of peptide/protein and non-peptide (carbohydrate) contents, water affinity and molecular weight (MW). AOM of all considered microorganisms are formed predominantly by hydrophilic substances with low values of specific UV absorbance (< 2 L/(m.mg)). Considerable portions of both types of AOM, i.e. extracellular and cellular organic matters are represented by substances with MW < 1 kDa or with MW > 100 kDa. However, the total amount and composition of AOM significantly depend on algal species and their growth. The obtained results imply that the knowledge of AOM...

This thesis deals with the application of BEAS-2B cell line for micronucleus assay in genetic toxicology. It is divided into two main parts: a) theoretical introduction to the analysis and search for suitable models for testing the impact of air pollution and manufactured nanoparticles, b) practical part that describes the results of micronuclei induction by polycyclic aromatic hydrocarbons (PAHs), extractable organic matter (EOM) from diesel exhaust particles obtained from emissions of three types of fuel and engineered nanoparticles. BEAS-2B cell line is a nonmalignant human model of lung epithelium which seems to be suitable for micronucleus assay. This assay is commonly used for determining the genotoxicity of various substances to wide variety of cell cultures and also in human studies. In this thesis, the following substances were tested: benzo[a]pyrene, 3-nitrobenzanthrone and 1-nitropyrene as carcinogenic PAHs commonly found in polluted air; EOMs from exhaust particles of 100 % diesel fuel, a blend of diesel fuel and 30 % of biodiesel, 100 % biodiesel and two types of engineered nanoparticles (TiO2 and Ag). The cells were treated with the compounds for 28, 48 and 72 hours. The results confirm the suitability of BEAS-2B cell line as a model for testing the genotoxicity of substances under...

This thesis deals with optical synthesis of unmodulated and modulated microwave signals. Generation of microwave signals based on optical heterodyning is discussed in detail. The effect of phase noise of laser on heterodyned output has been studied for different phase noise profiles. Towards this, we propose a generic algorithm to numerically model the linewidth broadening of a laser due to phase noise. Generation of microwave signals is demonstrated practically by conducting an optical heterodyning experiment. Signals ranging in frequency from 12.5 MHz to 27 GHz have been generated. Limitations of optical heterodyning based approach in terms of phase noise performance and frequency stability are discussed and practically demonstrated. A hardware-efficient Optical Phase Locked Loop (OPLL) is proposed to overcome these issues. Phase noise tracking performance of the proposed OPLL has been experimentally demonstrated. Phase noise values as low as -105 dBc/Hz at 10 KHz offset have been achieved. Optical modulators, owing to their extremely low electro-optic response time, can support high frequency modulating signals. This makes them highly attractive in comparison to their microwave counterparts. In this thesis, we propose techniques to generate microwave signals modulated at very high bit rates by down-converting the corresponding modulated optical signals to microwave domain. Down-conversion required for this process is achieved by optical heterodyning. The proposed concept has been theoretically analyzed, simulated and experimentally validated. Amplitude Modulated and ASK modulated microwave signals have been generated as Proof-of-Concept. Limitations posed by OPLL in generation of angle modulated microwave signals by optical heterodyning have been brought out. Schemes overcoming these limitations have been proposed towards generation of BPSK and QPSK modulated microwave signals. Integrated Optics (IO) technology has been studied as a means of implementation of the proposed concepts. IO components like Sinusoidal bends, Y-branch splitters and Electro-Optic-Modulators (EOMs) have been designed towards optical synthesis of modulated microwave signals. Propagation of modulated optical signal through these IO components has also been studied. An all-optic scheme based on Optical Beam Forming is proposed for transmission of QPSK modulated signal. Limitation of phase-shifting based approach, in terms of beam-squint, has been brought out. True-Time-Delay based approach has been proposed for applications demanding wide instantaneous bandwidth to avoid beam-squint. Algorithms / numerical methods required for analyses and simulations associated with the above-mentioned tasks have been evolved. This study is envisaged to provide useful insight into the realization of high-speed, compact, light-weight data transmitting systems based on Integrated Optics for future onboard spacecraft applications. This work, we believe, is a step towards realization of an Integrated Optic System-on-Chip solution for specific microwave data transmission applications.