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Dynamics and Structure of Cellular Aggregation

Dynamics and Structure of Cellular Aggregation

The fractal dimension is a measure for the regularity and density of the cluster. The more regular the clusters become, the more two dimensional (i.e. area-like) the patterns will be. After a stiff increase, the fractal dimension reaches a saturation value depending on the initial cell concentration (figure 3.11). The reason for this is shown in figure 3.12: the spatial structure of the aggregates (as measured by the fractal dimension) depends on their size. The bigger the aggregates become, the higher gets the fractal dimension meaning that the structure of larger aggregates is more regular than the structure of smaller aggregates. At a size of about 20.33 µm the dependency shifts from linear to a constant fractal dimension of 1.7. This is very similar to the patterns resulting from diffusion limited aggregation as reported by Witten Jr. and Sander (1981). While not proving diffusion limited aggregation as the mechanism at play here, it indicates that the random motion of the cells, i.e. the “diffusion”, might be an important factor in this process.
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On the structure of spoken Turkish

On the structure of spoken Turkish

followed by elaborating/linking information” does in any way collide with the left- branching and SOV syntax of Turkish. As has been pointed out by Auer (1990), in a noteworthy article on the structure of spoken Turkish, this is not the case. The linear order principle has to be understood as a principle concerning the distribution of information in texts. It is not, however, a syntactic principle. The postverbal position is an option with certain pragmatic prescriptions which make it attractive given the specific characteristics of unplanned/spoken Turkish discussed in Section 4 above. The use of şey actually is a response to this: the “dummy” is required in the syntacticized pre-verbal focus position in order to allow for a dislocation of constituents. And also the fact that ki and kim have rather lost their subordinating functions in a diachronic process and developed into a coordinating conjunction (cf. Erguvanlı 1980-1981, footnote 3) shows that Turkish integrated these forms into its own syntactic prerequisites (cf. Johanson 1996).
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Electronic Structure of Vanadium Phosphorus Oxides

Electronic Structure of Vanadium Phosphorus Oxides

EELS as well as NEXAFS were applied to probe the local electronic structure of oxygen and vanadium in β-VOPO 4 , respectively. The shape of the vanadium and oxygen edges is strongly related to the oxidation state of the vanadium and to the distortion of the co- ordination polyhedron [67]. EELS measurements were performed in the energy region of the V L 2 ,3 and the oxygen K ionization edges. Vanadium oxides and vanadium phos- phorus oxides are easily reduced by the electron beam in the TEM [67]. Therefore, special care was taken in order to minimize irradiation effects. A recorded spectrum is presented in Fig. 5.11 after background subtraction and multiple scattering correction [44]. The V L 2 ,3 ionization edges correspond to transitions from V 2p 1 /2 and 2p 3 /2 states to empty 3d states and show up as narrow peaks (white lines) at about 525.7 and 519 eV, respectively. From their position, the oxidation state of vanadium can be estimated [81] as +5. The maximum peak intensity of the two white lines is reversed with respect to the case of V 2 O 5 : while the intensity maximum of the L 2 edge is higher in the spectrum of V 2 O 5 , it is the L 3 edge that shows the highest intensity in β-VOPO 4 . This is due to the different width of the 3d band in the two compounds. In principle, the ratio between the inte- grated L 3 and L 2 intensity should correspond to the statistical ratio of 2:1 in the case of a d 0 initial state, if the background in the spectrum is correctly removed (which is difficult in the case of overlapping edges). The 2:1 intensity ratio is a result of the different initial state occupation (4 electrons in a 2p 3 /2 versus 2 electrons in a 2p 1 /2 state). But due to the shorter lifetime of a hole in a 2p 1 /2 state (it can be filled via a Coster-Kronig decay from a 2p 3 /2 state), the lifetime broadening of the L 2 edge is slightly larger than the one of the L 3 edge [70]. The effect of this difference on the final spectrum is bigger in the case of narrow 3d states and has to be taken into account in the comparison of the white line ratios.
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Electronic structure of multiorbital correlated systems

Electronic structure of multiorbital correlated systems

Another subject to analysis is structure of DOS. Whereas the lower Hubbard band has al- most the same position in all the calculation series (it may contain some fine structure we can not resolve because the features of the maximum entropy method we are using for analytical continuation of the Green function to the real axis, see sec. 2.3.7), the DOS features near the Fermi level exhibit reasonable dependence on both interaction type (full or reduced) and bath DOS. In case of LDA bath DOS the results (see figs. 5.9 and 5.10, left panels) are qualitatively consistent with the DOS obtained by Hirsch-Fye QMC [145] (see Fig. 5.7). At high tempera- ture ( β = 5 eV −1 , T ≈ 2300K) the satellite peak on the xy orbital at −1 eV is reproduced with both types of Coulomb interaction we used. With lowering the temperature (to β = 10 eV −1 , T ≈ 1160 K) this feature moves towards the Fermi level and becomes more sensitive to the type of Coulomb interaction (see Fig. 5.10, left panel): turning on the spin-flip terms leads to stronger hybridization between xy and xz , yz orbitals: position of the satellite peak on the xy orbital be-
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Structure of ideology: evidence from Serbia

Structure of ideology: evidence from Serbia

Political attitudes among the general public have often been portrayed as incoherent and disorganized. The situation is supposed to be still worse in the post-communist context due to various aspects of the 'triple transition'. These considerations, however, apply to the more general levels of attitude integration. At the more basic level, attitudes are supposed to converge due to their semantic similarity, or logical constraints in Converse’s terminology. According to the presented results, the Serbian public passed Middendorp’s test of “thinking ideologically”, since the political attitudes show “a degree of interrelatedness - along one or a few dimensions - which can be meaningfully interpreted" (Middendorp 1991, 60-61). The hypothesis about the multidimensionality and the hierarchical structure of political attitudes in Serbia, such as postulated in Eysenck’s (1975) Wilson’s (1973) or Middendorp’s (1991) models, is supported. Political attitudes at the most general level vary along four relatively independent dimensions: socialist conservatism, right-wing conservatism, social order and hierarchy orientation, and post-materialist orientation. The socialist conservatism dimension is defined by six primary attitudes: nationalism, militarism, socialist economy, rejection of the international integration, affirmative attitude towards the Milošević regime, and traditionalism. Primary attitudes that define right-wing conservatism include the clericalism factor, collectivism, traditionalism, punitiveness, and nationalism. The social order and hierarchy general ideological dimension includes primary attitudes such as the economic liberalism, liberalism, work ethic, elitism, and punitiveness. The post-materialist ideological dimension is based on environmentalist and pro- feminist attitudes.
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The inner structure of pyramid and capital structure: Evidence from China

The inner structure of pyramid and capital structure: Evidence from China

3 Methods 3.1 Samples Data regarding the inner structure of pyramid were manually collected from the annual report of listed companies; complementary data were sourced from the CSMAR (China Stock Market Accounting Research) database, which is the most widely used database on Chinese capital market (Su et al. 2015). This paper takes all the listed companies in both Shanghai and Shenzhen Stock Exchange Market between 2004 and 2009 as the original sample. The sample period was marked as beginning from 2004 because it was since then that all the listed companies in China were required by the CSRC (China Securities Regulatory Commission) to list the identities of their owners, as well as their chains of control, in their annual reports. Observations were deleted from our sample if they met the following conditions: (1) the companies belong to a financial industry (considering the special financial characteristics of these firms); (2) ST or PT companies 1 , since these companies are always in abnormal financial conditions and thus subject to great constraints on financing; (3) companies with extreme variable values, such as those with a debt ratio either greater than 1 or less than 0; (4) companies with incomplete data, or whose relevant data we were unable to locate. Following the selection process, we obtained 7729 firm-year observations with 1193 observations in 2004, 1207 observations in 2005, 1221 observations in 2006, 1292 observations in 2007, 1383 observations in 2008, and 1433 observations in 2009.
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Structure of three-body hypernuclei

Structure of three-body hypernuclei

In this thesis, we presented a detailed analysis of the structure of three-body hypernuclei. We thereby focused on the two most important systems, the hypertriton and the Λnn system, both offering an opportunity to study physics beyond the up- and down-quark sector. The first of them, the hypertriton, has been established in theory and experiments over decades, yet offering challenges and open questions. The second, Λnn is accessed experimentally rather recently [9]. Its actual nature however is up to debate until today. In the first part of the thesis we did an extensive analysis of the structure of both systems. In a pionless effective field theory we found both systems to be bound due to the Efimov effect, hence both systems display universal properties. We studied those in a dimer field approach studying Λd (nn) scattering, obtaining the Phillips line, a correlation between the binding energy and the scattering length. This allows us to tackle the impact of one of the current questions regarding the binding energy of the hypertriton. The new proposed value by the STAR collaboration [8] would decrease the value of the Λ-d scattering length by roughly 40% compared to the obtained 15.4 +4.3 −2.3 fm for the challenged value B Λ = 0.13 ± 0.05 MeV [5]. This small binding energy is often used to express that the hypertriton is shallowly bound. In our consecutive calculation of the three-body wave function and matter radii we find the assumed picture of a rather closely bound deuteron core with a far away Λ particle present. We find a large separation of 10.79 fm of these two components, compared to all other matter radii present within the system. This is in good agreement with the results obtained from a simple two-body estimate. As the scattering length before, the matter radius is once more directly connected to the binding energy, which allows us to directly connect those properties. As for the scattering length, the impact of the proposed binding energy is large. The simple two-body picture and hence the large separation of the Λ from the n-p pair, however, remains a reasonable picture.
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Inference and the structure of concepts

Inference and the structure of concepts

Now, according to Katz’s historical reconstruction, Frege’s semantics en- countered its first problem when Wittgenstein tried to apply it in the Trac- tatus. Broadly speaking, Frege’s point of view typically asserted that logi- cal relationships between sentences were a function of their logical structure. Thus, atomic sentences could not be related to other atomic sentences through their internal structure. In this sense, Wittgenstein writes that "It is a sign of an elementary proposition, that no elementary proposition can contradict it " ( Wittgenstein , 2001 [1921] , 4.211). In other words, Wittgenstein claimed that atomic sentences cannot have inferential properties, because inference is the result of truth-functional relations (see Rosenberg , 1968 , for a detailed expla- nation). However, he realized that some atomic propositions seemed to be in obvious relations among to each other. For instance, the sentences "The spot x is blue" and "The spot x is red" are in contradiction even if they are both atomic. Wittgenstein tried to justify this by saying that it was due to "the logical structure of colour" ( Wittgenstein , 2001 [1921] , 6.375 and 6.3751). How- ever, according to Katz, he later saw that this kind of relations between atomic propositions needed a more in-depth explanation, and he ended up by aban- doning the Fregean program in semantics altogether and proposing a radically different view of meaning. 3
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Synthesis and Crystal Structure of Nb0.84N

Synthesis and Crystal Structure of Nb0.84N

Fig. 5. Crystal structure of Nb 0 .84 N. Partially filled sites are shown fully occupied, and coordination polyhedra around the metals (balls) are given. A, B, and C denote layers of the niobium atoms, α, β, and γ layers of nitrogen atoms. quence γγγαααβββ (Fig. 5). As a consequence, lay- ers of edge-sharing NbN 6 octahedra alternate with two layers of NbN 6 edge-sharing prisms. Both sorts of lay- ers are connected via edges. Fig. 6 shows the coor- dination polyhedra around the two sorts of Nb, and in Table 2 some interatomic distances and angles are listed. The distances Nb–N of 212, 223, and 221 pm are in good agreement with values for typical Nb–N distances of 210 to 230 pm given in the Inorganic Crys- tal Structure Database ICSD [19].
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Intrinsic structure of the inferior colliculus

Intrinsic structure of the inferior colliculus

et al., 2008). Moreover, the largest sources of ascending inputs in the ICx arise from the brainstem somatosensory groups, e.g. cuneate, gracile nuclei and spinal trigeminal nucleus in the tactile system, and are indirectly connected to the motor system via the SC (Coleman and Clerici, 1987). For example, one experiment in the cat has shown that the ICx has a large receptive field to skin stimulation, i.e. the whole tactile sensory system is represented in the ICx (Aitkin and Boyd, 1978). We can therefore assume that the purpose of the ICx is to converge information from auditory, visual, motor and tactile systems. A large amount of intrinsic excitatory innervations in combination with a small amount of inhibitory innervations in general facilitates the integration, which is similar in the ventro-lateral ICc that is an integration region with inputs from all nuclei in the lower brainstem. Additionally, our results showed that similar to the lateral ICc cells, the ICx cells also had a large membrane time constant (compared to the combined data of dorsal-medial ICc and ventro- lateral ICc) that facilitates slow processing, which also has been reported by Chandrasekaran et al. (2013) based on the observation of the ceasing of tem- poral activities upon LL stimulation. As in the case of the ventro-lateral ICc, slow processing may enhance integration of the different sensory inputs (Ro- bards, 1979; Zhou and Shore, 2006), and a large amount of intrinsic excitatory and a small amount of inhibitory innervations may facilitate the integration of the multiple inputs (Chandrasekaran et al., 2013).
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Structure and Conformation of Photosynthetic Pigments and Related Compounds 3. Crystal Structure of ß-Carotene 

Structure and Conformation of Photosynthetic Pigments and Related Compounds 3. Crystal Structure of ß-Carotene 

The crystal structure o f the title com pound (C40H 56, M w = 536.8) has been redetermined by X-ray diffraction methods in order to achieve a structure at higher resolu­ tion suitable for theoretical calculations. The crystal sys­ tem is m onoclinic, P 2 ,/«, a = 7.656(2), b = 9.445(5), c - 23.536(15) Ä , ß = 93.41(2)°, V = 1698.8(15) Ä 3, Z = 2, D = 1.050 m g/m 3, 130 K. R = 0.071, R w = 0.076.

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The structure of SpoVT

The structure of SpoVT

Western Blot analysis is a very specific and sensitive immunological method of protein identification. For this, proteins of interest were transferred from a polyacrylamide gel onto a solid support via electro blotting as described in 6.2.8. To check the efficiency of the protein transfer, the membrane was stained with a Ponceau S solution (see 5.3.3) for 30 sec and transferred protein bands became visible. The stain was thoroughly washed away with ddH 2 O. The membrane was treated with WB 1 (see 5.3.2) two times for 10 min each. For blocking, the membrane was incubated in WB 2 at room temperature for 3 h by end-over-end rotation. Unbound BSA was washed away with WB 3 (10 min) and WB 1 (2 times, 10 min each). The primary antibody (polyclonal rabbit IgG, see 6.2.4) was applied in a 1:10000 dilution in WB 2 by overnight end-over-end rotation at 277 K. Accurately washing in WB 1 (several times) was performed prior to adding the secondary antibody (goat anti-rabbit IgG, horseradish, Sigma, 1:50000 dilution in WB 2). Incubation was done for 1 h at 277 K by end-over-end rotation. The membrane was washed several times in WB 1, covered with a 1:1 mixed luminol/H 2 O 2 reaction solution (Pierce) and incubated for 3 min (see 9.). Protein bands which were specifically recognised by the polyclonal rabbit anitbody became visible by subsequently exposing the membrane to X-ray films. Exposure was done several times for different time periods and the films were developed by standard film developing methods.
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Temporal Structure of AGN Light Curves

Temporal Structure of AGN Light Curves

Besides explaining the broad range of variability time-scales and the rms- flux relation, the fluctuating accretion model can also explain the spectral- timing properties of the variability, as noted by Kotov, Churazov, Gilfanov (2001). For example, it has long been known (e.g. Miyamoto & Kitamoto 1989, Nowak, Wilms & Dove 1999) that X-ray variations in black hole X-ray binaries (BHXRBs) often show hard lags, i.e. a delay in hard X-ray vari- ations with respect to soft X-rays, which is larger for variations on longer time-scales, and at higher energies. The magnitudes of the lags are typi- cally of order one per cent of the variability time-scale. Similar time-scale- dependent, hard lags have recently been discovered in AGN, albeit on much longer time-scales, commensurate with their higher black hole masses (e.g. Papadakis, Nandra & Kazanas 2001, Vaughan, Fabian & Nandra, 2003, M c Hardy et al. 2004). In their analytical extension to Lyubarskii’s model, Kotov et al. (2001) explain these lags by invoking a radially extended X-ray emitting region with an energy-dependent profile. In this scenario, the re- sponse of the emission to a fluctuation in the accretion flow is a function of the inward propagation time-scale, and hence radius of origin, of the fluctu- ation, combined with the emissivity profile. Hence, if the emissivity profile is more centrally concentrated at higher energies, hard-band lags are pro- duced such that the lags are larger for longer time-scale variations. Kotov et al. (2001) show that the same basic picture can also explain the energy dependence of the PSD of BHXRBs and AGN, where there is relatively more high-frequency power observed at higher energies than at lower energies (e.g. Nowak et al. 1999b,M c ardy et al. 2004). This is because the emitting region
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The iterative structure of corner operators

The iterative structure of corner operators

Let M be a manifold with edge Y of dimension q > 0. Then the space of all edge pseudo- differential operators on M , referring to the weight data g = (γ, γ − m, Θ) for a weight γ ∈ R and a weight interval Θ = (ϑ, 0], −∞ ≤ ϑ < 0 (which indicates an interval on the left of γ, and γ − m, respectively, where we control asymptotics) is defined to be the subset

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The Internal Structure of Influenza Virus 

The Internal Structure of Influenza Virus 

agglutinating activity, are associated with approxi­ mately spherical particles of 116 — 124 mfx diameter. Electron microscopy on frozen dried material of in­ fluenza virus revealed a diameter of only 80 mju 19. This is in agreement with a value of 82 mju from sedimentation experiments, corrected for a density of the virus of 1.2 20. This density, measured in suc­ rose solution, seems to be higher than the density of the virus in water18. Our figures are based on the hydrated state for components having a density near 1.1. We assume therefore that the average virus
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Calculations on the ^-Structure of Dimethylsulfoxide 

Calculations on the ^-Structure of Dimethylsulfoxide 

n o t necessarily sym m etric rotors is n o t available. I n ad d itio n a detailed analysis of th e internal ro ta tio n in DMSO b y Dreizler a n d D endl [8] yielded a hindering p o ten tial of a b o u t 2900 cal/mol, and v ery few ro tatio n al tran sitio n s of th e ground state h av e observable splittings. Therefore the con­ trib u tio n s of in tern al ro ta tio n to th e harm onic v ib ratio n al p a rt of th e ground sta te ro tatio n al c o n stan ts were ap p ro x im ated by calculations w ith harm onic torsional oscillations.
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Exploring the impact of structure directing agents on the synthesis and structure of imidazolate frameworks

Exploring the impact of structure directing agents on the synthesis and structure of imidazolate frameworks

In chapter 4 of this work, the synthesis of MIFs with gemini surfactants is explored, in order to investigate the effects of surfactant charge density and geometry on the formed structures. Whilst previous results showed that changes in the length of the used surfactants do not translate into changes of the geometry of obtained mesostructures, the question wether or not cubic or hexagonal mesostructures of zeolitic imidazolate frameworks (ZIFs) are accessible via microemulsion synthesis remained unanswered. The experiments presented in chapter 4 are adressing this issue by using gemini-surfactants in order to control charge density and geometry of the used surfactants to a higher degree as compared to single chain-surfactants, such as the previously used CTAB. Whilst the synthesis of cubic or hexagonally mesostrucured materials was not successful, the experiments provided improved understanding of the formation mechanism of MIFs, which are formed due to the presence of halogenides during the microemulsion synthesis. Whilst a plethora of lamellar structured mesostructured imidazolate frameworks (MIFs) with different spacings, however identical inner-layer structure, are acessible this way, the proposed formation mechanism also provides explanation, to why the used surfactants need to be altered with regard to the used counter-ion in order to suppress the formation of the lamellar MIFs in favor for differently structured mesomaterials.
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Structure of Flames in Flame Interaction Zones

Structure of Flames in Flame Interaction Zones

This modular design of the burners allows for using perforated plates of different sizes and open areas, generating a variety of turbulence intensities. The bluff bodies can be removed from the burners, which permits for variation in flame shape. The large aspect ratio of the burner exit plane allows for a negligible mean velocity gradient in the 𝑧- direction and formation of a statistically two-dimensional premixed turbulent flame along the center of the burner at different flame shapes and flow conditions. To achieve Bunsen flames stabilization at bulk flow velocities larger than 5 m/s, two types of pilot flames are used: small “anchoring” pilots, which are located close to the exit of the burners and help anchor the flames on the experiment, and larger “back-support” pilots, which provide adiabatic or super- adiabatic combustion products around the flames. Air and fuel flow through the main burners are measured with thermal mass flow meters (Teledyne Hastings Instruments HFM-205 and HFM-201). The air and fuel flow through the pilot flame flow circuits are measured using calibrated rotameters. The burners are mounted to a small mill stage, which allows for measurement access to differernt locations in the flames while keeping the lasers and cameras stationary. The separation distance between the burners can be varied by sliding each burner independently on the top of the mill stage. For the rest of the paper, the burner separation (used interchangeably with flame spacing) is defined as the distance between the burner centerlines, as marked in Figure 1(c).
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Structure of Azadirachtin B 

Structure of Azadirachtin B 

6 H. R em bold et al. • Structure o f Azadirachtin B ta tio n o f 2 D -C O S Y and N O E S Y plots. T h e C O S Y plots o f azadirachtin B confirm th e spin analysis as show n in T ab le I. By use of th e IN E P T -te c h n iq u e th e co rresp o n d in g carb o n and p ro to n reso n an ces of azadirachtin B w ere assigned. T h e L’C reso n an ces are in full a g re em e n t w ith th e reso n a n ce s pu b lish ed by K lenk et al. [10]. In th e N O E S Y plots th e follow ing cross relaxations w ere o bserved: 9/18, 5; 30/6, 7, 15, 11, O M e(12); 7/21; 28/5'; 17/22. A fte r saponification th e reso n an ces of tiglic acid d isa p p e a r and m ost chem ical shifts in th e sp ectru m o f d etigloylazadirach- tin B are identical w ith those of az ad ira ch tin B. H o w ­ ev e r, the sp e ctra o f azad irach tin B an d of th e detig- loyl d erivative also clearly show d ifferences in th e reso n a n ce signals o f th e p ro to n s at C - l, C -2 b , C-3, C-5, C-9, C-2.8a, C -28b. T h e d ifferences in th e re so ­ nance lines o f H - l , H -2 b , H -3, H -5, H -9 could be explained w ith a su b stitu tio n by tiglic acid e ith e r in
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Crystal Structure of Bis(triphenylstannyl)sulfite 

Crystal Structure of Bis(triphenylstannyl)sulfite 

T he reaction of bis(triorganostannyl)oxides, (R 3Sn)20 , w ith sulfur dioxide has been studied re ­ peated ly [1,2] w ith the result th at b is(triorganostan- nyl)sulfites, R 3S n 0 - S ( 0 ) - 0 S n R 3, can be p rep ared by insertion of S 0 2 into the Sn-O bond. These com ­ p o unds are difficult to crystallize for R = alkyl [1,2], and although a m icrocrystalline solid was isolated in the case of R = Ph [2], direct structural evidence could n o t be o b tain ed . S tructural inform ation w ould be of in terest for com parison with the struc­ tu ral p ro p erties of bis(triorganostannyl)carbo- nates, R 3S n 0 - C ( 0 ) - 0 S n R 3 [3] or bis(trim ethyl- stannyl)selenite, M e3S n 0 - S e ( 0 ) - 0 S n M e 3 [4], for which polym eric chains w ere observed. H ere we re p o rt th at con tro lled hydrolysis of bis(triphenyl- stannyl)sulfur diim ide 1 [5] provides an alternative ro u te to bis(triphenyltin)sulfite 2, and th at crystal­ line m aterial suitable for X -ray structural analysis can be obtained.
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