Developing an Unmanned Aerial Vehicle (UAV) multi-sensor payload carrier for air quality monitoring

Emissions of gases and particles from sea-faring ships have been shown to impact on the atmospheric chemistry and climate. To efficiently monitor and report these emissions found from a ship’s plume, the concept of using a multi-rotor or UAV to hover inside or near the exhaust of the ship to actively record the data in real time is being developed. However, for the required sensors obtain the data; their sensors must face into the airflow of the ships plume. This report presents an approach to have sensors able to read in the chemicals and particles emitted from the ship without affecting the flight dynamics of the multi-rotor UAV by building a sealed chamber in which a pump can take in the surrounding air (outside the downwash effect of the multi-rotor) where the sensors are placed and can analyse the gases safely. Results show that the system is small, lightweight and air-sealed and ready for flight test.

Structural Ordering of Disordered Ligand-Binding Loops of Biotin Protein Ligase into Active Conformations as a Consequence of Dehydration

Mycobacterium tuberculosis (Mtb), a dreaded pathogen, has a unique cell envelope composed of high fatty acid content that plays a crucial role in its pathogenesis. Acetyl Coenzyme A Carboxylase (ACC), an important enzyme that catalyzes the first reaction of fatty acid biosynthesis, is biotinylated by biotin acetyl-CoA carboxylase ligase (BirA). The ligand-binding loops in all known apo BirAs to date are disordered and attain an ordered structure only after undergoing a conformational change upon ligand-binding. Here, we report that dehydration of Mtb-BirA crystals traps both the apo and active conformations in its asymmetric unit, and for the first time provides structural evidence of such transformation. Recombinant Mtb-BirA was crystallized at room temperature, and diffraction data was collected at 295 K as well as at 120 K. Transfer of crystals to paraffin and paratone-N oil (cryoprotectants) prior to flash-freezing induced lattice shrinkage and enhancement in the resolution of the X-ray diffraction data. Intriguingly, the crystal lattice rearrangement due to shrinkage in the dehydrated Mtb-BirA crystals ensued structural order of otherwise flexible ligand-binding loops L4 and L8 in apo BirA. In addition, crystal dehydration resulted in a shift of similar to 3.5 angstrom in the flexible loop L6, a proline-rich loop unique to Mtb complex as well as around the L11 region. The shift in loop L11 in the C-terminal domain on dehydration emulates the action responsible for the complex formation with its protein ligand biotin carboxyl carrier protein (BCCP) domain of ACCA3. This is contrary to the involvement of loop L14 observed in Pyrococcus horikoshii BirA-BCCP complex. Another interesting feature that emerges from this dehydrated structure is that the two subunits A and B, though related by a noncrystallographic twofold symmetry, assemble into an asymmetric dimer representing the ligand-bound and ligand-free states of the protein, respectively. In-depth analyses of the sequence and the structure also provide answers to the reported lower affinities of Mtb-BirA toward ATP and biotin substrates. This dehydrated crystal structure not only provides key leads to the understanding of the structure/function relationships in the protein in the absence of any ligand-bound structure, but also demonstrates the merit of dehydration of crystals as an inimitable technique to have a glance at proteins in action.

Puolustuskykyinen valtio vai Ruotsin hälytyskello? : Suomen sotilasstrateginen asema kylmän sodan alkuvuosien asiantuntija-arvioissa

The doctoral thesis deals with Finnish and foreign expert s analyses of Finland s military strategic position and defence capability, dating back to the early years of the Cold War. Finland s military high command prepared assessments of the country s strategic position and of the capability of the Defence Forces as grounds for defence planning. Since Finland was located on the Cold War dividing line, the foreign powers were also monitoring the development of Finland s situation. The research carried out had access to the armed forces internal assessments, as well as to analyses prepared by the military intelligence services of Sweden, Britain and the United States. One of the working hypotheses was that after the WWII the ability military leadership to estimate the security political needs of the country and the organisation of its defence was severely weakened so that the dangers of the international development were not perceived and the gradual erosion of defence capability was partly unnoticed. This hypothesis proved to be wrong. Even if the Finnish military intelligence was much weaker than during the war, it was able to provide the military leadership with information of the international military development for the most part. The military leadership was also fully aware of the weakening of the defence capability of the country. They faced the difficult task of making the country s political leadership, i.e. President Paasikivi and the government, also understand the gravity of the situation. Only in the last years of his term in office Paasikivi started to believe the warnings of the military. According to another hypothesis, outside observers considered the Finnish armed forces to primarily act as reinforcements for the Soviet Red Army, and they believed that, in the event of a full-scale war, the Finns would not have been able or even willing to resist a Soviet invasion of Sweden and Norway through Finland. The study confirmed that this was approximately the view the Swedes, the British and the Americans had of the Finnish forces. Western and Swedish intelligence assessments did not show confidence in Finland s defence ability and the country was regarded almost as a Soviet satellite. Finland s strategic position was, however, considered slightly different from that of the Soviet-occupied Eastern European countries. Finland had been forced to become part of the Soviet sphere of interest and security system and this was sealed by the Finno-Soviet Treaty of Friendship, Cooperation, and Mutual Assistance in 1948. Finland had little importance to the military interests of the Western powers. In Sweden s defence planning, however, Finland played a significant role as an alarm bell of a possible Soviet surprise attack, as well as defensive frontline and buffer zone.

Application of reversed phase circular paper chromatography to the analysis of higher fatty acids

A detailed study of various reversed phase systems for the qualitative analysis of fatty acids has been made and it has been shown, among other things, that the liquid paraffin-aqueous methanol system is a most convenient one. The details of a fairly simple and rapid method for the quantitative estimation of higher fatty acids have also been discussed.

Infra-red absorption bands of co-ordinated water in titanium complexes

ORANGE red and amorphous peroxy-titanium complexes of oxalic, malonic and maleic acids1-3, when vacuum-dried, have co-ordinated water molecules firmly bonded to the central titanium atom as shown in formula (I). The peroxy-oxygen from these compounds is slowly lost even at room temperature because of the strained peroxy-group3,4. The compounds, when kept at 95°-100°C. for about three days, give deperoxygenated compounds of the type (II). However, a sample of peroxy-titanium oxalate sealed in a glass tube lost all its peroxy-oxygen in about four years and gave a white crystalline basic oxalate (II). The amorphous nature of the compounds may be due to random hydrogen bonding in the complexes. The crystallinity observed in one of the deperoxygenated titanyl oxalates may be due to the rearrangement of the molecules during ageing for more than four years. The infra-red absorption of these compounds was studied to find out the effect of co-ordination and hydrogen bonding on the infra-red bands of the free water.

mRNA-binding protein HuR in breast carcinogenesis

Breast cancer is the most common cancer among women. Although its prognosis has improved nowadays, methods to predict the progression of the disease or to treat it are not comprehensive. This thesis work was initiated to elucidate in breast carcinogenesis the role of HuR, a ubiquitously expressed mRNA-binding protein that regulates gene expression posttranscriptionally. HuR is predominantly nuclear, but it shuttles between the nucleus and the cytoplasm, and this nucleocytoplasmic translocation is important for its function as a RNA-stabilizing and translational regulator. HuR has been associated with diverse cellular processes, for example carcinogenesis. The specific aims of my thesis work were to study the prognostic value of HuR in breast cancer and to clarify the mechanisms by which HuR contributes to breast carcinogenesis. My ultimate goal is, by better understanding the role of HuR in breast carcinogenesis, to aid in the discovery of novel targets for cancer therapies. HuR expression and localization was studied in paraffin-embedded preinvasive (atypical ductal hyperplasia, ADH, and ductal carcinoma in situ, DCIS) specimens as well in sporadic and familial breast cancer specimens. Our results show that cytoplasmic HuR expression was already elevated in ADH and remained elevated in DCIS as well as in cancer specimens. Clinicopathological analysis showed that cytoplasmic HuR expression associated with the more aggressive form of the disease in DCIS, and in cancer specimens it proved an independent marker for poor prognosis. Importantly, cytoplasmic HuR expression was significantly associated with poor outcome in the subgroups of small (2 cm) and axillary lymph node-negative breast cancers. HuR proved to be the first mRNA stability protein the expression of which is associated in breast cancer with poor outcome. To explore the mechanisms of HuR in breast carcinogenesis, lentiviral constructs were developed to inhibit and to overexpress the HuR expression in a breast epithelial cell line (184B5Me). Our results suggest that HuR mediates breast carcinogenesis by participating in processes important in cell transformation, in programmed cell death, and in cell invasion. Global gene expression analysis shows that HuR regulates genes participating in diverse cellular processes, and affects several pathways important in cancer development. In addition, we identified two novel target transcripts (connective tissue growth factor, CTGF, and Ras oncogene family member 31, RAB31) for HuR. In conclusion, because cytoplasmic HuR expression in breast cancer can predict the outcome of the disease it could serve in clinics as a prognostic marker. HuR accumulates in the cytoplasm even at its non-invasive stage (ADH and DCIS) of the carcinogenic process and supports functions essential in cell alteration. These data suggest that HuR contributes to carcinogenesis of the breast epithelium.

Genomic alterations in Myeloproliferative Neoplasms and Myelodysplastic Syndromes

Myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematopoietic disorders whose etiology and molecular pathogenesis are poorly understood. During the past decade, enormous developments in microarray technology and bioinformatics methods have made it possible to mine novel molecular alterations in a large number of malignancies, including MPN and MDS, which has facilitated the detection of new prognostic, predictive and therapeutic biomarkers for disease stratification. By applying novel microarray techniques, we profiled copy number alterations and microRNA (miRNA) expression changes in bone marrow aspirate and blood samples. In addition, we set up and validated an miRNA expression test for bone marrow core biopsies in order to utilize the large archive material available in many laboratories. We also tested JAK2 mutation status and compare it with the in vitro growth pattern of hematologic progenitors cells. In the study focusing on 100 MPN cases, we detected a Janus kinase 2 (JAK2) mutation in 71 cases. We observed spontaneous erythroid colony growth in all mutation-positive cases in addition to nine mutation negative cases. Interestingly, seven JAK2V167F negative ET cases showed spontaneous megakaryocyte colony formation, one case of which also harbored a myeloproliferative leukemia virus oncogene (MPL) mutation. We studied copy number alterations in 35 MPN and 37 MDS cases by using oligonucleotide-based array comparative hybridization (array CGH). Only one essential thrombocythemia (ET) case presented copy number alterations in chromosomes 1q and 13q. In contrast, MDS cases were characterized by numerous novel cryptic chromosomal aberrations with the most common copy number losses at 5q21.3q33.1 and 7q22.1q33, while the most common copy number gain was trisomy 8. As for the study of the bone marrow core biopsy samples, we showed that even though these samples were embedded in paraffin and underwent decalcification, they were reliable sources of miRNA and suitable for array expression analysis. Further, when studying the miRNA expression profiles of the 19 MDS cases, we found that, compared to controls, two miRNAs (one human Epstein-Barr virus (miR-BART13) miRNA and one human (has-miR-671-5p) miRNA) were downregulated, whereas two other miRNAs (hsa-miR-720 and hsa-miR-21) were upregulated. However, we could find no correlation between copy number alterations and microRNA expression when integrating these two data. This thesis brings to light new information about genomic changes implicated in the development of MPN and MDS, and also underlines the power of applying genome-wide array screening techniques in neoplasias. Rapid advances in molecular techniques and the integration of different genomic data will enable the discovery of the biological contexts of many complex disorders, including myeloid neoplasias.

Gibbs energies of formation of chromium carbides

The carbon potentials corresponding to the two-phase mixtures Cr + Cr23C6, Cr23C6 + Cr7C3, and Cr7C3 + Cr3C2 in the binary system Cr-C were measured in the temperature range 973 to 1173 K by using the methane-hydrogen gas equilibration technique. Special precautions were taken to prevent oxidation of the samples and to minimize thermal segregation in the gas phase. The standard Gibbs energies of formation of Cr23C6, Cr7C3, and Cr3C2 were derived from the measured carbon potentials. These values are compared with those reported in the literature. The Gibbs energies obtained in this study agree well with those obtained from solid-state cells incorporating CaF2 and ThO2(Y2O3) as solid electrolytes and sealed capsule isopiestic measurements reported in the literature.

Chopped nonlinear magneto-optic rotation: A technique for precision measurements

We have developed a technique for precise measurement of small magnetic fields using nonlinear magneto-optic rotation (NMOR). The technique relies on the resonant laser beam being chopped. During the on time, the atoms are optically pumped into an aligned ground state (Delta m=2 coherence). During the off time, they freely precess around the magnetic field at the Larmor frequency. If the on-off modulation frequency matches (twice) the Larmor precession frequency, the rotation is resonantly enhanced in every cycle, thereby making the process like a repeated Ramsey measurement of the Larmor frequency. We study chopped-NMOR in a paraffin-coated Cs vapor cell. The out-of-phase demodulated rotation shows a Lorentzian peak of linewidth 85 mu G, corresponding to a sensitivity of 0.15nG/root Hz. We discuss the potential of this technique for the measurement of an atomic electric-dipole moment. Copyright (C) EPLA, 2011

Continuous distribution kinetics for the thermal degradation of LDPE in solution

Polymer degradation in solution has several advantages over melt pyrolysis, The degradation of low-density polyethylene (LDPE) occurs at much lower temperatures in solution (280-360degreesC) than in conventional melt pyrolysis (400-450degreesC). The thermal degradation kinetics of LDPE in solution was investigated in this work. LDPE was dissolved in liquid paraffin and degraded for 3 h at various temperatures (280-360degreesC). Samples were taken at specific times and analyzed with high-pressure liquid chromatography/gel permeation chromatography for the molecular weight distribution (MWD), The time evolution of the MWD was modeled with continuous distribution kinetics. Data indicated that LDPE followed random-chain-scission degradation. The rapid initial drop in molecular weight, observed up to 45 min, was attributed to the presence of weak links in the polymer. The rate coefficients for the breakage of weak and strong links were determined, and the corresponding average activation energies were calculated to be 88 and 24 kJ/mol, respectively. (C) 2002 John Wiley Sons, Inc.

Direct ultrafast laser written C-band waveguide amplifier in Er-doped chalcogenide glass

This paper reports the fabrication and characterization of an ultrafast laser written Er-doped chalcogenide glass buried waveguide amplifier; Er-doped GeGaS glass has been synthesized by the vacuum sealed melt quenching technique. Waveguides have been fabricated inside the 4 mm long sample by direct ultrafast laser writing. The total passive fiber-to-fiber insertion loss is 2.58 +/- 0.02 dB at 1600 nm, including a propagation loss of 1.6 +/- 0.3 dB. Active characterization shows a relative gain of 2.524 +/- 0.002 dB/cm and 1.359 +/- 0.005 dB/cm at 1541 nm and 1550 nm respectively, for a pump power of 500 mW at a wavelength of 980 nm. (C) 2012 Optical Society of America

Studies on the Aging Characteristics of Base Oil with Amine Based Antioxidant in Steel-on-Steel Lubricated Sliding

An industrial base oil, a blend of different paraffin fractions, is heated to 130 degrees C (1) in the ambient and (2) for use as a lubricant in a steel pin on a steel disk sliding experiment. The base oil was tested with and without test antioxidants: dimethyl disulfide (DMDS) and alkylated diphenylamine (ADPA). Primary and secondary oxidation products were monitored continuously by FTIR over a 100 h period. In addition, friction and wear of the steel pin were monitored over the same period and the chemical transformation of the pin surface was monitored by XPS. The objective of this work is to observe the catalytic action of the steel components on the oil aging process and the efficacy of the antioxidant to reduce oxidation of oil used in tribology as a lubricant. Possible mechanistic explanations of the aging process as well as its impact on friction and wear are discussed.

Gibbs free energy of formation of rhodium sulfides

Using a solid-state electrochemical technique, thermodynamic properties of three sulfide phases (RhS0.882, Rh3S4, Rh2S3) in the binary system (Rh + S) are measured as a function of temperature over the range from (925 to 1275) K. Single crystal CaF2 is used as the electrolyte. The auxiliary electrode consisting of (CaS + CaF2) is designed in such a way that the sulfur chemical potential converts into an equivalent fluorine potential at each electrode. The sulfur potentials at the measuring electrodes are established by the mixtures of (Rh + RhS0.882), (RhS0.882 + Rh3S4) and (Rh3S4 + Rh2S3) respectively. A gas mixture (H-2 + H2S + Ar) of known composition fixes the sulfur potential at the reference electrode. A novel cell design with physical separation of rhodium sulfides in the measuring electrode from CaS in the auxiliary electrode is used to prevent interaction between the two sulfide phases. They equilibrate only via the gas phase in a hermetically sealed reference enclosure. Standard Gibbs energy changes for the following reactions are calculated from the electromotive force of three cells: 2.2667Rh (s) + S-2 (g) -> 2.2667RhS(0.882) (s), Delta(r)G degrees +/- 2330/(J . mol(-1)) = -288690 + 146.18 (T/K), 4.44RhS(0.882) (s) + S-2 (g) -> 1.48Rh(3)S(4) (s), Delta(r)G degrees +/- 2245/(J . mol(-1)) = -245596 + 164.31 (T/K), 4Rh(3)S(4) (s) + S-2 (g) -> 6Rh(2)S(3) (s), Delta(r)G degrees +/- 2490/(J . mol(-1)) = -230957 + 160: 03 (T/K). Standard entropy and enthalpy of formation of rhodium sulfides from elements in their normal standard states at T = 298.15 K are evaluated. (C) 2013 Elsevier Ltd. All rights reserved.

Rational molecular dynamics scheme for predicting optimum concentration loading of nano-additive in phase change materials

The present study deals with the diffusion and phase transition behaviour of paraffin reinforced with carbon nano-additives namely graphene oxide (GO) and surface functionalized single walled carbon nanotubes (SWCNT). Bulk disordered systems of paraffin hydrocarbons impregnated with carbon nano-additives have been generated in realistic equilibrium conformations for potential application as latent heat storage systems. Ab initio molecular dynamics(MD) in conjugation with COMPASS forcefield has been implemented using periodic boundary conditions. The proposed scheme allows determination of optimum nano-additive loading for improving thermo-physical properties through analysis of mass, thermal and transport properties; and assists in determination of composite behaviour and related performance from microscopic point of view. It was observed that nanocomposites containing 7.8% surface functionalised SWCNT and 55% GO loading corresponds to best latent heat storage system. The propounded methodology could serve as a by-pass route for economically taxing and iterative experimental procedures required to attain the optimum composition for best performance. The results also hint at the large unexplored potential of ab-initio classical MD techniques for predicting performance of new nanocomposites for potential phase change material applications. (C) 2015 Author(s).

Investigations into enhanced wax production with combustion synthesized Fischer-Tropsch catalysts

Combustion synthesized (CS) cobalt catalysts deposited over two supports, alumina and silica doped alumina (SDA), were characterized and tested for its Fischer-Tropsch (FT) activity. The properties of CS catalysts were compared to catalysts synthesized by conventional impregnation method (IWI). The CS catalysts resulted in 40-70% increase in the yield of C6+ hydrocarbons compared to MI catalysts. The FT activity for CS catalysts showed formation of long chain hydrocarbon waxes (C24+) compared to the formation of middle distillates (C-10-C-20) for IWI synthesized catalysts, indicating higher hydrocarbon chain growth probability for CS catalysts. This is ascribed to the smaller crystallite sizes, increased degree of cobalt reduction and consequentially, a higher number of active metal sites, exposed over the catalyst surface. Additionally, 12-13% increase in the overall C6+ hydrocarbon yield is realized for SDA-CS catalysts, compared to Al2O3-CS catalysts. The improved performance of CS-SDA catalysts is attributed to 48% increase in cobalt dispersion compared to Al2O3 supported CS catalysts, which is again caused by the decrease in the cobalt -support interaction for SDA supports. The metal support interactions were analyzed using XPS and H-2 TPR-TPD experiments. Combustion method produced catalysts with smaller crystallite size (17-18 nm), higher degree of reduction (similar to 92%) and higher metal dispersion (16.1%) compared to the IWI method. Despite its enhanced properties, the CS catalysts require prominently higher reduction temperatures (similar to 1100-1200 K). The hydrocarbon product analysis for Al2O3 supported catalyst showed higher paraffin wax concentrations compared to SDA supported catalysts, due to the lower surface basicity of Al2O3. This work reveals the impact of the CS catalysts and the nature of support on FT activity and hydrocarbon product spectrum. (C) 2016 Elsevier Ltd. All rights reserved.