Relative survival of Escherichia coli and Salmonella typhimurium in a tropical estuary

Microcosm studies have been carried out to find out the relative survival of Escherichia coli and Salmonella typhimurium in a tropical estuary. Survival has been assessed in relation to the important self-purifying parameters such as biotic factors contained in the estuarine water, toxicity due to the dissolved organic and antibiotic substances in the water and the sunlight. The results revealed that sunlight is the most important inactivating factor on the survival of E. coli and S. typhimurium in the estuarine water. While the biological factors contained in the estuarine water such as protozoans and bacteriophages also exerted considerable inactivation of these organisms, the composition of the water with all its dissolved organic and inorganic substances was not damaging to the test organisms. Results also indicated better survival capacity of E. coli cells under all test conditions when compared to S. typhimurium

Determination of charge carrier transport in radio frequency plasma polymerized aniline thin films

The carrier transport mechanism of polyaniline (PA) thin films prepared by radio frequency plasma polymerization is described in this paper. The mechanism of electrical conduction and carrier mobility of PA thin films for different temperatures were examined using the aluminium–PA–aluminium (Al–PA–Al) structure. It is found that the mechanism of carrier transport in these thin films is space charge limited conduction. J –V studies on an asymmetric electrode configuration using indium tin oxide (ITO) as the base electrode and Al as the upper electrode (ITO–PA–Al structure) show a diode-like behaviour with a considerable rectification ratio

Length-weight relationship, relative condition factor (Kn) and morphometry of Arius subrostratus (Valenciennes, 1840) from a coastal wetland in Kerala

The length – weight relationship and relative condition factor of the shovel nose catfish, Arius subrostratus (Valenciennes, 1840) from Champakkara backwater were studied by examination of 392 specimens collected during June to September 2008. These fishes ranged from 6 to 29 cm in total length and 5.6 to 218 g in weight. The relation between the total length and weight of Arius subrostratus is described as Log W = -1.530+2.6224 log L for males, Log W = - 2.131 + 3.0914 log L for females and Log W = - 1.742 + 2.8067 log L for sexes combined. The mean relative condition factor (Kn) values ranged from 0.75 to 1.07 for males, 0.944 to 1.407 for females and 0.96 to 1.196 for combined sexes. The length-weight relationship and relative condition factor showed that the well-being of A. subrostratus is good. The morphometric measurements of various body parts and meristic counts were recorded. The morphometric measurements were found to be non-linear and there is no significant difference observed between the two sexes. From the present investigation, the fin formula can be written as D: I, 7; P: I, 12; A: 17 – 20; C: 26 – 32. There is no change in meristic counts with the increase in body length.

Computations in Relative Algebraic K-Groups

Let G be finite group and K a number field or a p-adic field with ring of integers O_K. In the first part of the manuscript we present an algorithm that computes the relative algebraic K-group K_0(O_K[G],K) as an abstract abelian group. We solve the discrete logarithm problem, both in K_0(O_K[G],K) and the locally free class group cl(O_K[G]). All algorithms have been implemented in MAGMA for the case K = \IQ. In the second part of the manuscript we prove formulae for the torsion subgroup of K_0(\IZ[G],\IQ) for large classes of dihedral and quaternion groups.

Influence of the buffer environment on the Relative Biological Effectiveness of carbon ion radiation, investigated by Scanning Force Microscopy and gel electrophoresis

This work focuses on the analysis of the influence of environment on the relative biological effectiveness (RBE) of carbon ions on molecular level. Due to the high relevance of RBE for medical applications, such as tumor therapy, and radiation protection in space, DNA damages have been investigated in order to understand the biological efficiency of heavy ion radiation. The contribution of this study to the radiobiology research consists in the analysis of plasmid DNA damages induced by carbon ion radiation in biochemical buffer environments, as well as in the calculation of the RBE of carbon ions on DNA level by mean of scanning force microscopy (SFM). In order to study the DNA damages, besides the common electrophoresis method, a new approach has been developed by using SFM. The latter method allows direct visualisation and measurement of individual DNA fragments with an accuracy of several nanometres. In addition, comparison of the results obtained by SFM and agarose gel electrophoresis methods has been performed in the present study. Sparsely ionising radiation, such as X-rays, and densely ionising radiation, such as carbon ions, have been used to irradiate plasmid DNA in trishydroxymethylaminomethane (Tris buffer) and 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES buffer) environments. These buffer environments exhibit different scavenging capacities for hydroxyl radical (HO0), which is produced by ionisation of water and plays the major role in the indirect DNA damage processes. Fragment distributions have been measured by SFM over a large length range, and as expected, a significantly higher degree of DNA damages was observed for increasing dose. Also a higher amount of double-strand breaks (DSBs) was observed after irradiation with carbon ions compared to X-ray irradiation. The results obtained from SFM measurements show that both types of radiation induce multiple fragmentation of the plasmid DNA in the dose range from D = 250 Gy to D = 1500 Gy. Using Tris environments at two different concentrations, a decrease of the relative biological effectiveness with the rise of Tris concentration was observed. This demonstrates the radioprotective behavior of the Tris buffer solution. In contrast, a lower scavenging capacity for all other free radicals and ions, produced by the ionisation of water, was registered in the case of HEPES buffer compared to Tris solution. This is reflected in the higher RBE values deduced from SFM and gel electrophoresis measurements after irradiation of the plasmid DNA in 20 mM HEPES environment compared to 92 mM Tris solution. These results show that HEPES and Tris environments play a major role on preventing the indirect DNA damages induced by ionising radiation and on the relative biological effectiveness of heavy ion radiation. In general, the RBE calculated from the SFM measurements presents higher values compared to gel electrophoresis data, for plasmids irradiated in all environments. Using a large set of data, obtained from the SFM measurements, it was possible to calculate the survive rate over a larger range, from 88% to 98%, while for gel electrophoresis measurements the survive rates have been calculated only for values between 96% and 99%. While the gel electrophoresis measurements provide information only about the percentage of plasmids DNA that suffered a single DSB, SFM can count the small plasmid fragments produced by multiple DSBs induced in a single plasmid. Consequently, SFM generates more detailed information regarding the amount of the induced DSBs compared to gel electrophoresis, and therefore, RBE can be calculated with more accuracy. Thus, SFM has been proven to be a more precise method to characterize on molecular level the DNA damage induced by ionizing radiations.

Influence of occupation number of single particle levels on K - K charge transfer in collisions of 90 keV - Ne{^9+} on Ne

The influence of the occupation of the single particle levels on the impact parameter dependent K - K charge transfer occuring in collisions of 90 keV Ne{^9+} on Ne was studied using coupled channel calculations. The energy eigenvalues and matrixelements for the single particle levels were taken from ab initio self consistent MO-LCAO-DIRAC-FOCK-SLATER calculations with occupation numbers corresponding to the single particle amplitudes given by the coupled channel calculations.

Nuclear charge radii from X-ray transitions in muonic atoms of carbon, nitrogen and oxygen

Energies of muonic X-rays of the K-series of carbon, nitrogen and oxygen have been measured with an accuracy of about 15 eV. Root mean square radii of the nuclear charge distributions were deduced. The results 2.49±0.05 fm for carbon, 2.55 ±0.03 fm for nitrogen and 2.71 ±0.02 fm for oxygen are in good agreement at comparable accuracy with recent electron scattering data.

The electronic structure of the group 6 oxyanions [MO_4]^2-, where M = Cr, Mo, W, and element 106

The electronic structure of the group 6 oxyanions [MO_4]^2-, where M = Cr, Mo, W, and element 106 have been calculated using the Dirac-Slater Discrete Variational method. Results of the calculations show a relative decrease in the metal-oxygen bond strengths for the [E106O_4]^2- ion in the solid state compared to that for the [WO_4]^2- anion. Calculated energies of the electronic charge-transfer transitions are indicative of a strong possible luminescence of [El06O_4]^2- in the blue-violet area. In solutions [El06O_4]^2- will be the most stable ion out of the entire series. Estimated reduction potential E^0 (El06O^2-_4/E106O^3-_4) equal to -1.60V shows only a slightly increased stability of the +6 oxidation state for element 106 in comparison with W.

Highly Sensitive Sensor Based On Intracavity Laser Absorption Spectroscopy By Means of Relative Intensity Noise

This thesis concerns with the main aspects of medical trace molecules detection by means of intracavity laser absorption spectroscopy (ICLAS), namely with the equirements for highly sensitive, highly selective, low price, and compact size sensor. A novel two modes semiconductor laser sensor is demonstrated. Its operation principle is based on the competition between these two modes. The sensor sensitivity is improved when the sample is placed inside the two modes laser cavity, and the competition between the two modes exists. The effects of the mode competition in ICLAS are discussed theoretically and experimentally. The sensor selectivity is enhanced using external cavity diode laser (ECDL) configuration, where the tuning range only depends on the external cavity configuration. In order to considerably reduce the sensor cost, relative intensity noise (RIN) is chosen for monitoring the intensity ratio of the two modes. RIN is found to be an excellent indicator for the two modes intensity ratio variations which strongly supports the sensor methodology. On the other hand, it has been found that, wavelength tuning has no effect on the RIN spectrum which is very beneficial for the proposed detection principle. In order to use the sensor for medical applications, the absorption line of an anesthetic sample, propofol, is measured. Propofol has been dissolved in various solvents. RIN has been chosen to monitor the sensor response. From the measured spectra, the sensor sensitivity enhancement factor is found to be of the order of 10^(3) times of the conventional laser spectroscopy.

Magnetic interactions between transition metal impurities and clusters mediated by low-dimensional metallic hosts: A first principles theoretical investigation

The magnetic properties and interactions between transition metal (TM) impurities and clusters in low-dimensional metallic hosts are studied using a first principles theoretical method. In the first part of this work, the effect of magnetic order in 3d-5d systems is addressed from the perspective of its influence on the enhancement of the magnetic anisotropy energy (MAE). In the second part, the possibility of using external electric fields (EFs) to control the magnetic properties and interactions between nanoparticles deposited at noble metal surfaces is investigated. The influence of 3d composition and magnetic order on the spin polarization of the substrate and its consequences on the MAE are analyzed for the case of 3d impurities in one- and two-dimensional polarizable hosts. It is shown that the MAE and easy- axis of monoatomic free standing 3d-Pt wires is mainly determined by the atomic spin-orbit (SO) coupling contributions. The competition between ferromagnetic (FM) and antiferromagnetic (AF) order in FePtn wires is studied in detail for n=1-4 as a function of the relative position between Fe atoms. Our results show an oscillatory behavior of the magnetic polarization of Pt atoms as a function of their distance from the magnetic impurities, which can be correlated to a long-ranged magnetic coupling of the Fe atoms. Exceptionally large variations of the induced spin and orbital moments at the Pt atoms are found as a function of concentration and magnetic order. Along with a violation of the third Hund’s rule at the Fe sites, these variations result in a non trivial behavior of the MAE. In the case of TM impurities and dimers at the Cu(111), the effects of surface charging and applied EFs on the magnetic properties and substrate-mediated magnetic interactions have been investigated. The modifications of the surface electronic structure, impurity local moments and magnetic exchange coupling as a result of the EF-induced metallic screening and charge rearrangements are analysed. In a first study, the properties of surface substitutional Co and Fe impurities are investigated as a function of the external charge per surface atom q. At large inter-impurity distances the effective magnetic exchange coupling ∆E between impurities shows RKKY-like oscillations as a function of the distance which are not significantly affected by the considered values of q. For distances r < 10 Å, important modifications in the magnitude of ∆E, involving changes from FM to AF coupling, are found depending non-monotonously on the value and polarity of q. The interaction energies are analysed from a local perspective. In a second study, the interplay between external EF effects, internal magnetic order and substrate-mediated magnetic coupling has been investigated for Mn dimers on Cu(111). Our calculations show that EF (∼ 1eV/Å) can induce a switching from AF to FM ground-state magnetic order within single Mn dimers. The relative coupling between a pair of dimers also shows RKKY-like oscillations as a function of the inter-dimer distance. Their effective magnetic exchange interaction is found to depend significantly on the magnetic order within the Mn dimers and on their relative orientation on the surface. The dependence of the substrate-mediated interaction on the magnetic state of the dimers is qualitatively explained in terms of the differences in the scattering of surface electrons. At short inter-dimer distances, the ground-state configuration is determined by an interplay between exchange interactions and EF effects. These results demonstrate that external surface charging and applied EFs offer remarkable possibilities of manipulating the sign and strength of the magnetic coupling of surface supported nanoparticles.

Asymptotically Zero Energy Computing Using Split-Level Charge Recovery Logic

The dynamic power requirement of CMOS circuits is rapidly becoming a major concern in the design of personal information systems and large computers. In this work we present a number of new CMOS logic families, Charge Recovery Logic (CRL) as well as the much improved Split-Level Charge Recovery Logic (SCRL), within which the transfer of charge between the nodes occurs quasistatically. Operating quasistatically, these logic families have an energy dissipation that drops linearly with operating frequency, i.e., their power consumption drops quadratically with operating frequency as opposed to the linear drop of conventional CMOS. The circuit techniques in these new families rely on constructing an explicitly reversible pipelined logic gate, where the information necessary to recover the energy used to compute a value is provided by computing its logical inverse. Information necessary to uncompute the inverse is available from the subsequent inverse logic stage. We demonstrate the low energy operation of SCRL by presenting the results from the testing of the first fully quasistatic 8 x 8 multiplier chip (SCRL-1) employing SCRL circuit techniques.

Relative Contributions of Internal and External Features to Face Recognition

The central challenge in face recognition lies in understanding the role different facial features play in our judgments of identity. Notable in this regard are the relative contributions of the internal (eyes, nose and mouth) and external (hair and jaw-line) features. Past studies that have investigated this issue have typically used high-resolution images or good-quality line drawings as facial stimuli. The results obtained are therefore most relevant for understanding the identification of faces at close range. However, given that real-world viewing conditions are rarely optimal, it is also important to know how image degradations, such as loss of resolution caused by large viewing distances, influence our ability to use internal and external features. Here, we report experiments designed to address this issue. Our data characterize how the relative contributions of internal and external features change as a function of image resolution. While we replicated results of previous studies that have shown internal features of familiar faces to be more useful for recognition than external features at high resolution, we found that the two feature sets reverse in importance as resolution decreases. These results suggest that the visual system uses a highly non-linear cue-fusion strategy in combining internal and external features along the dimension of image resolution and that the configural cues that relate the two feature sets play an important role in judgments of facial identity.

Gobierno y gobernancia de los territorios, sectorialidad y territorialidad de las políticas públicas

El hecho de que, desde la Constitución de 1991, normas y sentencias tiendan en considerar que los ejecutivos locales (alcaldes, gobernadores) deben ser unos agentes regidores que practican el gobierno del territorio y la “descentralización controlada” más que unos actores gobernantes, defensores de la gobernancia de sus territorios, plantea la cuestión de saber por qué y cómo aquéllos pueden combinar este doble rol. La mayor parte de la respuesta se encuentra en el examen simultáneo de la lógica de regulación de las políticas pública (Muller, 1997 y 2002) y de las condiciones de su implementación en el territorio o “despliegue territorial” (Medellín, 2003).La territorialidad de una política pública se refiere, según Muller, a una situación en la cual la lógica dominante de una política pública es una lógica territorial u horizontal (regulación de un territorio geográfico en una dialéctica centro-periferia), mientras la sectorialidad se refiere a una situación en la cual la lógica dominante de una política pública es una lógica sectorial o vertical (regulación de la reproducción de un sector determinado verticalmente en una dialéctica global-sectorial). A cada lógica de regulación de las políticas públicas le corresponde una manera de gobernar un territorio: el gobierno del territorio para la sectorialidad y la gobernancia de los territorios para la territorialidad.Al contrario del caso francés en el cual la construcción del Estado marca el fin de una lógica de territorialidad (la “territorialidad tradicional”), el Estado colombiano es un Estado endémico, un Estado fragmentado confrontado a la lucha por el control territorial y el temor a la fractura de la unidad territorial (Navas, 2003). Su capacidad parcial por cubrir todo el territorio y actuar sobre él (su “territorialidad parcial” según Medellín) afecta su gobernabilidad y el despliegue territorial de las políticas públicas, sometido a negociaciones inciertas, cercanas a la temática de la gobernancia.Por ello, la gobernabilidad en Colombia sólo es posible mediante políticas públicas híbridas, hijas del “matrimonio indisoluble de la sectorialidad y de la territorialidad”, de la “secterritorialidad”, que combina en proporción variable lógica sectorial (o sectorialidad, que implica centralización) y lógica territorial (o territorialidad, que implica descentralización), gracias a un modo de gobierno híbrido, la “gobiernancia” del territorio, ésta es una “dosificación” compleja entre gobier-no y gobernancia. Es, entonces, posible determinar el grado de territorialidad y de sectorialidad de una política pública en un momento dado y clasificar las políticas públicas según su grado de territorialidad y de sectorialidad, es decir, según la importancia relativa de sus lógicas de regulación.Si el periodo que empieza al iniciar los años setenta, y que termina al iniciar los años ochenta es un periodo en el cual domina primordialmente la sectorialidad y se asegura la gobernabilidad recurriendo casi exclusivamente al gobierno del territorio a través del despliegue territorial separado de cada sector, el periodo que va de 1984 a la época actual, caracterizado por la “descentralización controlada”, señala un cambio parcial de lógica de regulación de las políticas públicas a través del recurrir parcial a la lógica de territorialidad como respuesta a alguna crisis de sectorialidad.Como bien lo muestra el análisis y la evaluación de las políticas públicas de vivienda de interés social, ordenamiento y desarrollo del territorio municipal, educación y acueducto y alcantarillado, la gobernabilidad en este secundo periodo está asegurada, entonces, sólo gracias a la gobiernancia en los territorios o combinación entre el gobierno del territorio y la gobernancia de los territorios, es decir, gracias a un modo de gobierno híbrido que les permite a los ejecutivos locales conciliar su inclinación por la gobernancia de sus territorios y sus obligaciones en cuanto al gobierno del territorio y ser, al mismo tiempo, actores gobernantes y agentes regidores.-----Since the 1991 Constitution, most rulings and sentences tend to consider that individuals in charge of the local executive power (mayors, governors) should be some sort of tuling aldermen responsible for their particular territories and their “controlled decentralization” instead of actual governing actors, advocates and defenders of the governance of their territories. This fact raises the questions of why and how they can possibly play this double role. The bulk of the answer to this question can be found by examining both the logic behind public policies (Muller) and the conditions in whixh these are implemented in each territory, or “territorial deployment” (Medellìn).According to Muller, the territoriality of a particular public policy refers to a situation whereby the prevailing logic is territorial or horizontal (regulation of a geographical territory follows a center-periphery scheme), whereas its sectoriality refers to a situation whereby the prevailing logic is sectorial or vertical (regulation of a sector’s reproduction is vertically determined by a global-sectorial scheme). For each regulation logic behind public policies there is a corresponding way of governing a particular territory: governing the territory for the sake of sectoriality, and governing it for the sake of territoriality.As opposed to the French case, whereby the construction of the State signals the purposes of a territorial logic (“traditional territoriality”), the Colombian State is na endemic one, a fragmented State struggling for territorial control and in fear of the fragmentation of territorial unity (Navas). Its limited capacity to cover the whole territory and to act on it (its “limited or partial territoriality”, according to Medellín) affects governability as well as the deployment of public policies, which is frequently subject to uncertain negotiations related to the problem of governance.That es why governability in Colombia is only possible through hybrid public policies, which are in turn the result of the “indissoluble marriage between sectoriality and territoriality”, the result of a sort of “secterritoriality” which combines in various proportions a sectorial logic (or sectoriallity, which implies centralization) and a territorial logic (or territoriallity, which implies decentralization), all due to a hybrid form of governmen, or “governance” of the territory, a complex and variable dosage of both government and governance. Keeping this in mind, it is possible to establish the degree of territoriality and sectoriality of a public policy at a particular time, and to classify public policies according to their degree of territoriality and/or sectoriality, that is, according to the relative importance of the logics behind their regulation.From the early 70s to the early 80s, sectoriality prevailed and governability was guaranteed almost exclusively through the separate territorial deployment of each sector, then, from 1984 to the present, “controlled decentralization” has shown partial changes in the regulation logic behind public policies by resorting, at least in part, to a logic of territoriality in response to some sort of sectorriality crisis.As can be clearly seen after analyzing and evaluatin public policies in matters such as statesubsidized housing, municipal land development and legislation, education, water and sewage services, governability during this second period can only be guaranteed by governance in the territories or by a combination of both, government in the territory and governance in the territories. In other words, governability is possible thanks to a type of hybrid government that allows those in charge of exercising local executive power to reconcile their bias towards the governance of their teritories and their duties vis-àvis the government of the territory, but capable of being, at the same time, governing actors and ruling agents, active modern-day aldermen.

Análisis del discurso de la UE en materia de derechos humanos y democracia en relación con las aspiraciones de Turquía a ser miembro pleno de la organización (2000-2012)

El propósito de esta monografía consiste en analizar el discurso de la Unión Europea en materia de Derechos Humanos y Democracia y su importancia en el proceso de ampliación de la Organización. Se estudia y explica el criterio de condicionalidad del discurso como una medida preventiva y/o sancionatoria para la entrada de Turquía a la UE, estableciendo que dicho discurso es un factor determinante en las negociaciones entre la UE y Turquía. Para ésto, se analiza el discurso europeo a partir del análisis del discurso ideológico, de Teun Van Dijk, y el discurso de la condicionalidad, de Maria del Carmen Muñoz Rodríguez, lo cual permite hacer un estudio detallado de la incidencia del discurso de la UE en el proceso de negociación de la adhesión de Turquía a la Unión.

Poder e influencia en el liderazgo transformacional

Como proyecto de grado, el presente trabajo consiste en una revisión teórica de los conceptos de liderazgo, poder e influencia, junto con las posibles relaciones que entre ellos se pueden presentar. Para ello, cada concepto es definido de manera individual, y con base en ello, se identifica la dependencia que tienen estos conceptos entre sí y la importancia dentro del desarrollo del liderazgo transformacional actual. Para lograr lo propuesto, se llevó a cabo la revisión de una parte de la literatura académica presente en libros, revistas académicas, bases de datos y documentos relacionados con los temas y conceptos tratados. A partir de ello, se entendió la evolución del concepto del liderazgo y los enfoques presentados desde la década de los 1920´s hasta la actualidad, junto con el modelo de rango total y el tipo transaccional y transformacional del liderazgo, para luego definir el papel y la importancia de los conceptos de poder, los tipos de poder, la influencia y las tácticas de influencia, y así, identificar las posibles relaciones que se presentan entre los conceptos y la importancia de estos en el entorno organizacional actual.