Value Of D0 Research Articles

Quadruple bonds in MoC: Accurate calculations and precise measurement of the dissociation energy of low-lying states of MoC.

In the present work, the electronic structure and chemical bonding of the MoC X3Σ- ground state and the six lowest excited states, A3Δ, a1Γ, b5Σ-, c1Δ, d1Σ+, and e5Π, have been investigated in detail using multireference configuration interaction methods and basis sets, including relativistic effective core potentials. In addition, scalar relativistic effects have been considered in the second order Douglas-Kroll-Hess approximation, while spin-orbit coupling has also been calculated. Five of the investigated states, X3Σ-, A3Δ, a1Γ, c1Δ, and d1Σ+, present quadruple σ2σ2π2π2 bonds. Experimentally, the predissociation threshold of MoC was measured using resonant two-photon ionization spectroscopy, allowing for a precise measurement of the dissociation energy of the ground state. Theoretically, the complete basis set limit of the calculated dissociation energy with respect to the atomic ground state products, including corrections for scalar relativistic effects, De(D0), is computed as 5.13(5.06) eV, in excellent agreement with our measured value of D0(MoC) of 5.136(5) eV. Furthermore, the calculated dissociation energies of the states having quadruple bonds with respect to their adiabatic atomic products range from 6.22 to 7.23eV. The excited electronic states A3Δ2 and c1Δ2 are calculated to lie at 3899 and 8057 cm-1, also in excellent agreement with the experimental values of DaBell et al., 4002.5 and 7834 cm-1, respectively.

Relevant Studies on Cytokines Level and CAR-T Expansion Associated to CD7 CAR-T Therapy

Background In the past few years, CD7 became a highly reliable marker of CAR-T therapy treating T cell acute lymphocytic leukemia(T-ALL). In this case, better understanding of CD7 CAR-T therapy on cellular level became meaningful. Aim To figure out the correlation of cytokines level and CAR-T expansion to CRS and outcomes of CD7 CAR-T therapy. Methods Peripheral blood samples were collected from 70 patients treated with CD7 CAR-T from Dec. 2020 to Nov. 2022 in Hebei Yanda Ludaopei Hospital. There were 56 males and 14 females, from 2-year old to 60 with median age 19. Based on criteria of CRS and assessment results, 70 patients were split in different groups. According to CRS level, two groups were set as low (CRS0-1, 56 of 70) group and high group (CRS2-4, 14 of 70). Due to assessment results, 55 of 70 were classified as CR/CRi group, 15 of 70 were Non-CR group. 24 Cytokines (IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IL-17F, IL-22,TNFα, TNFβ, IFN-γ, IL-2RA/sCD25, MIP-1α, MCP-1, GM-CSF, IL-15, REG3a, Elafin, ST-2, Granzyme B, TNFRI) were measure with microbeads with 2 lasers 4 colour Calibur flow cytometer. CAR-T cells, target cells(CD7+ cells), T cells subsets(CD3+, CD4+, CD8+, CD8+TCM, CD8+TEM, Treg) were tested with 3 lasers 8-10 colour Canto flow cytometer. All the cellular variations were calculated by comparing value of peak-time to value of D0 which was used as baseline. Time points day0, 4, 7, 11, 14, 21, 30 were monitored after CAR-T infusion. FCM data was analyzed with Diva software. Prism 8 was used for statistic analyse. Results According to patient characteristics (shown in table 1a), no matter under which criteria, patients in all 4 groups had similar median age and transfection efficiency. First of all, based on criteria of CRS level, patients were split into low group and high group(upper table 1a). CAR-T peak time was appeared significantly later(p=0.0274) in high group. Along with that, in high group, CD8+TEM(effect memory T) cells was amplified significantly more than that in low group at peak time point(p=0.0258). Clearance rates of target cells(CD7+) in low group were significantly higher(p=0.003). According to cytokine secretion levels, the level of IL-4(p=0.0183), IL-6(p<0.0001), IL-8(p=0.043), IL-10(p<0.0001), IL-22(p=0.0463), IFN-γ(p<0.0001), sCD25(<0.0001), MCP-1(p=0.0092), IL-15(p=0.0029), Granzyme B(p=0.0027) were significant higher in high group(as shown in figure 1). All median peak time of those 10 cytokines in high group were calculated, from day 10 up to day 15 after CAR-T infusion. According to the time gap between each of 10 cytokines with CAR-T expansion, MCP-1 had the largest time gap, which means MCP-1 reached peak time 9 days earlier than that of CAR-T cells. The median peak-time gap between cytokines level with CAR-T cells expansion was 6 days(showed in table 1b). Secondly, due to criteria of assessment results of CD7 CAR-T therapies, 70 patients were classified as CR/CRi group and Non-CR group (lower table 1a). CAR-T expansion, T cell subsets variation showed no statistical difference between two groups, and only target cells (CD7+) clearance rate was significantly higher in CR group. For all 24 cytokines measured in this study showed no significant differences between both groups. Conclusions Base on our data, IL-4, IL-6, IL-8, IL-10, IL-15, IL-22, IFN-γ, sCD25, MCP-1, and Granzyme B were correlated to severity of CRS after CD7 CAR-T therapy. Those 10 cytokines showed positive correlation to the level of CRS, and reached peak time earlier than that of CAR-T expansion, which means all these 10 cytokines could be used as indicators to predict occurrence and severity of CRS. Concurrence time of peak expansion of CD7 CAR-T cells, and amplification of CD8+TEM cells were significantly related to CRS. For all the patients who reached complete remission or CRi, CD7+ clearance rates were higher with statistical significance. Our results proved potential indicators for CRS prediction and prognosis.

CrN, CuB, and AuB: A Tale of Two Dissociation Limits.

Predissociation thresholds corresponding to dissociation at ground state separated atom limits (SALs) have been recorded in this group for more than 100 d- and f-block metal-containing molecules. The metal atom electronic degeneracies in these molecules generate a dense manifold of electronic states that allow high-lying vibronic levels to couple to pathways leading to dissociation. However, CrN, CuB, and AuB fail to dissociate at their ground SAL. Instead, the molecules remain bound at energies that far surpass their bond dissociation energies (BDEs), and their bonds break only when excited at or above an excited SAL. Sharp predissociation thresholds at excited SALs nevertheless allowed BDEs to be derived: D0(CrN): 3.941(22) eV; D0(CuB): 2.26(15) eV; D0(Au11B): 3.724(3) eV. A previous measurement of D0(AlCr) is re-evaluated as dissociating to a higher energy limit, giving a revised value of D0(AlCr) = 1.32(2) eV. A discussion of this physical behavior is presented.

Theoretical dissociation, ionization, and spin-orbit energetics of the diatomic platinum hydrides PtH, PtH+, and PtH.

Spin-orbit configuration interaction (SO-CI) and coupled-cluster [CCSDT(Q)] theoretical methods are combined to evaluate zero-temperature thermochemical properties of PtH, PtH+, and PtH-. We obtain vibrational zero-point energies and spin-orbit stabilization energies, which lead to predictions for observable quantities: ionization energy IE(PtH) = (9.44 ± 0.07) eV; electron affinity EA(PtH) = (1.65 ± 0.04) eV; and dissociation energies D0(Pt-H) = (329.6 ± 3.9) kJ mol-1, D0(Pt+-H) = (279.3 ± 5.7) kJ mol-1, and D0(Pt--H) = (285.0 ± 2.4) kJ mol-1 (uncertainty coverage factor = 2). Compared with available experiments, our value of D0(Pt+-H) is higher by (8 ± 8) kJ mol-1, EA(PtH) is higher by 0.15eV, and D0(Pt-H) is lower than the upper bound by (2 ± 4) kJ mol-1.

Mechanical Properties of Spruce Wood Extracted from GLT Beams Loaded by Fire

Heating wood to high temperature changes either temporarily or permanently its physical properties. This issue is addressed in the present contribution by examining the effect of high temperature on residual mechanical properties of spruce wood, grounding on the results of full-scale fire tests performed on GLT beams. Given these tests, a computational model was developed to provide through-thickness temperature profiles allowing for the estimation of a charring depth on the one hand and on the other hand assigning a particular temperature to each specimen used subsequently in small-scale tensile tests. The measured Young’s moduli and tensile strengths were accompanied by the results from three-point bending test carried out on two groups of beams exposed to fire of a variable duration and differing in the width of the cross-section, b=100 mm (Group 1) and b=160 mm (Group 2). As expected, increasing the fire duration and reducing the initial beam cross-section reduces the residual bending strength. A negative impact of high temperature on residual strength has also been observed from simple tensile tests, although limited to a very narrow layer adjacent to the charring front not even exceeding a typically adopted value of the zero-strength layer d0=7 mm. On the contrary, the impact on stiffness is relatively mild supporting the thermal recovery property of wood.

Bond dissociation energies of ScSi, YSi, LaSi, ScC, YC, LaC, CoC, and YCH.

Predissociation thresholds of the ScSi, YSi, LaSi, ScC, YC, LaC, CoC, and YCH molecules have been measured using resonant two-photon ionization spectroscopy. It is argued that the dense manifold of electronic states present in these molecules causes prompt dissociation when the bond dissociation energy (BDE) is exceeded, allowing their respective predissociation thresholds to provide precise values of their bond energies. The BDEs were measured as 2.015(3) eV (ScSi), 2.450(2) eV (YSi), 2.891(5) eV (LaSi), 3.042(10) eV (ScC), 3.420(3) eV (YC), 4.718(4) eV (LaC), 3.899(13) eV (CoC), and 4.102(3) eV (Y-CH). Using thermochemical cycles, the enthalpies of formation, ΔfH0K°(g), were calculated as 627.4(9.0) kJ mol-1 (ScSi), 633.1(9.0) kJ mol-1 (YSi), 598.1(9.0) kJ mol-1 (LaSi), 793.8(4.3) kJ mol-1 (ScC), 805.0(4.2) kJ mol-1 (YC), 687.3(4.2) kJ mol-1 (LaC), 760.1(2.5) kJ mol-1 (CoC), and 620.8(4.2) kJ mol-1 (YCH). Using data for the BDEs of the corresponding cations allows ionization energies to be obtained through thermochemical cycles as 6.07(11) eV (ScSi), 6.15(13) eV (YSi), 5.60(10) eV (LaSi), 6.26(6) eV (ScC), 6.73(12) or 5.72(11) eV [YC, depending on the value of D0(Y+-C) employed], and 5.88(35) eV (LaC). Additionally, a new value of D0(Co+-C) = 4.045(13) eV was obtained based on the present work and the previously determined ionization energy of CoC. An ionization onset threshold allowed the measurement of the LaSi ionization energy as 5.607(10) eV, in excellent agreement with a prediction based on a thermochemical cycle. Chemical bonding trends are also discussed.

Dynamics of blood brain barrier permeability and tissue microstructure following controlled cortical impact injury in rat: A dynamic contrast-enhanced magnetic resonance imaging and diffusion kurtosis imaging study

ObjectiveThe blood-brain barrier (BBB) and cerebral tissue microstructure can be impaired following traumatic brain injury (TBI). However, the spatiotemporal changes of BBB leakage and tissue microstructure are not completely understood. In this study, we evaluated the spatiotemporal changes of BBB leakage and tissue microstructure using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion kurtosis imaging (DKI) in controlled cortical impact (CCI) rats. Materials and methodsThe DCE-MRI parameters volume transfer coefficient (Ktrans) and DKI parameters were longitudinally measured in bilateral cortex, hippocampus, thalamus and corpus callosum (CC) at baseline (D0), acute stage (D1, D3), and subacute stage (D7, D14 and D28) post-injury. Immunohistochemistry analysis was performed at D28 after MRI scanning. Repeated-measures ANOVA was used to assess the temporal changes of MRI parameters. ResultsKtrans abnormality was only localized to ipsilateral perilesional cortex with a significant temporal change (F = 144.2, p < 0.0001). Compared to baseline, increased mean kurtosis (MK) was observed in ipsilateral regions of cortex and hippocampus and CC for all the time points (p < 0.05 for all). Increased MK was also observed in ipsilateral thalamus (p = 0.005) at subacute stage but not at acute stage while no change was observed with MD and FA (p > 0.05 for both). In ipsilateral cortex, the overall Ktrans value of D0, D1, D3, D7, D14, and D28 post-injury were significantly correlated with MK value (r = 0.84, p < 0.0001). The CCI group showed higher staining of glial fibrillary acidic protein (GFAP) and ionized calcium binding adaptor molecule 1 (Iba-1) and lower staining of neuron-specific nuclear protein (NeuN) and myelin basic protein (MBP) in ipsilateral regions of cortex, hippocampus, thalamus and CC (p < 0.05 for all) as compared to control group. There were no significant differences in the contralateral regions by immunohistochemistry. ConclusionThe BBB disruption reflected by Ktrans correlated well with MK value in ipsilateral cortex. In addition, MK could detect the delayed microstructural changes in thalamus. DCE-MRI and DKI could be used to assess the BBB breakdown and cerebral microstructural changes of TBI.

Evaluation of a 3D unstructured-mesh finite element model for dam-break floods

This paper aims to comprehensively understand a 3D model for simulating dam-break floods through three test cases. The advantages and characteristics of this model are evaluated from different perspectives. Firstly, vertical inertial is considered in the 3D model. In the existing 1D and 2D flooding models, vertical inertia is usually ignored, resulting in unreliable results in high vertical inertia situations. A circular dam break case was designed and widely used for testing 2D models. Here it has been adopted to test the 3D model. Evident difference has been observed when compared with 2D modelling results. In order to reduce the vertical inertial in this case, we scaled the vertical size by 1:100, while kept the original horizontal size, then amplified the results according to the Froude number scaling rule. The results of the scaled model is very close to 2D modelling results. Therefore, the difference between the 3D and 2D modelling results are mainly caused by the vertical inertia. Thus it can be seen that 3D modelling techniques are needed when vertical inertia is not negligible. Secondly, the use of unstructured mesh makes this model more powerful in operating with complex topography, which is very important in real-world application. Five similar cases with different topography demonstrated that the complexity of topography affects the numerical solution process directly. However, this 3D model has powerful ability in utilizing very complex terrain. Thirdly, sensitivity of the model to the thickness of the artificial thin layer in dry areas (d0) and mesh resolution (Δx) have been analysed with a realistic dike-break flooding case. Smaller d0 produces more realistic results but costs more computational time. The model is more sensitive to mesh resolution when the terrain is more complex. Therefore, a multi-scale mesh with high-resolution in areas with complex terrain and low-resolution in flat regions is a good choice for this model. Also, trade-offs between modelling precision and efficiency should be considered when choosing a proper value of d0 and mesh resolution.

Super-diffusion of excited carriers in semiconductors

The ultrafast spatial and temporal dynamics of excited carriers are important to understanding the response of materials to laser pulses. Here we use scanning ultrafast electron microscopy to image the dynamics of electrons and holes in silicon after excitation with a short laser pulse. We find that the carriers exhibit a diffusive dynamics at times shorter than 200 ps, with a transient diffusivity up to 1,000 times higher than the room temperature value, D0≈30 cm2s−1. The diffusivity then decreases rapidly, reaching a value of D0 roughly 500 ps after the excitation pulse. We attribute the transient super-diffusive behaviour to the rapid expansion of the excited carrier gas, which equilibrates with the environment in 100−150 ps. Numerical solution of the diffusion equation, as well as ab initio calculations, support our interpretation. Our findings provide new insight into the ultrafast spatial dynamics of excited carriers in materials.

Bond energies of ThO+ and ThC+: A guided ion beam and quantum chemical investigation of the reactions of thorium cation with O2 and CO

Kinetic energy dependent reactions of Th(+) with O2 and CO are studied using a guided ion beam tandem mass spectrometer. The formation of ThO(+) in the reaction of Th(+) with O2 is observed to be exothermic and barrierless with a reaction efficiency at low energies of k/kLGS = 1.21 ± 0.24 similar to the efficiency observed in ion cyclotron resonance experiments. Formation of ThO(+) and ThC(+) in the reaction of Th(+) with CO is endothermic in both cases. The kinetic energy dependent cross sections for formation of these product ions were evaluated to determine 0 K bond dissociation energies (BDEs) of D0(Th(+)-O) = 8.57 ± 0.14 eV and D0(Th(+)-C) = 4.82 ± 0.29 eV. The present value of D0 (Th(+)-O) is within experimental uncertainty of previously reported experimental values, whereas this is the first report of D0 (Th(+)-C). Both BDEs are observed to be larger than those of their transition metal congeners, TiL(+), ZrL(+), and HfL(+) (L = O and C), believed to be a result of lanthanide contraction. Additionally, the reactions were explored by quantum chemical calculations, including a full Feller-Peterson-Dixon composite approach with correlation contributions up to coupled-cluster singles and doubles with iterative triples and quadruples (CCSDTQ) for ThC, ThC(+), ThO, and ThO(+), as well as more approximate CCSD with perturbative (triples) [CCSD(T)] calculations where a semi-empirical model was used to estimate spin-orbit energy contributions. Finally, the ThO(+) BDE is compared to other actinide (An) oxide cation BDEs and a simple model utilizing An(+) promotion energies to the reactive state is used to estimate AnO(+) and AnC(+) BDEs. For AnO(+), this model yields predictions that are typically within experimental uncertainty and performs better than density functional theory calculations presented previously.

Ordered structures of nanorods induced by the helixes of semiflexible polymer chains

Self-assembly of nanoparticles, such as nanospheres, nanorods (NRs), and nanotubes, in polymer systems is one of the most prominent and promising candidates for the development of novel materials with high mechanical, optical, and electrical performances. A most concerned topic on the nanoparticle/polymer composites is the spatial arrangement and distribution of nanoparticles in the nanocomposites, which is controlled by the competition between the entropic packing constraints related to the incompatibility between species with different sizes and geometries, and the enthalpic consequences of a variety of polymer-nanoparticle interactions. The studies on the nonspherical nanoparticles, such as NRs, are of more challenging than on spherical nanoparticles, because both positional and orientational ordering of anisotropic nanoinclusion have an important influence on the morphology of nanocomposition, while those studies are necessary for applications of nanoscopic anisotropic objects in photovoltaic and filled emission devices. When low-volume fractions of NRs are immersed in a binary, phase-separating blend, the rods can self-assemble into needle-like, percolating networks and this special structure can enhance the macroscopic electrical conductivity and mechanical property of the material. When an electric field is applied, the phase separations of ligand-functionalized NRs in a polymer matrix and densely packed hexagonal arrays of NRs are produced. In this paper, by employing the coarse-grained model and molecular dynamics simulation, we explore the structures of nanocomposites in which a small number of NRs bind with semiflexible polymer chain. The morphology of NRs/polymer mixture is greatly affected by the bending energy b of semiflexible polymer and the binding energy D0 between NRs and semiflexible polymer. If the binding energy D0 is less than 1.1kBT, the NRs are almost free and a gas-like phase is observed. For a suitably large value of D0, three completely different morphologies of NRs/polymer mixtures are identified, namely, the side-to-side parallel aggregation of NRs, the end-to-end parallel aggregation of NRs, and the dispersion of NRs. For the flexible polymer chain (i.e., small bending energy b), the sideto- side parallel aggregation structure of NRs and the disordered conformation of adsorbed polymer chain are observed. In general, a typical equilibrium conformation of free flexible polymer chain is random coil, the binding energy between NRs and polymer can lead to the collapse of a random coil for flexible polymer chain, and the NRs aggregate in the manner of the side-to-side parallel to each other because the enthalpy is maximized through sharing the more polymer monomers between neighbor NRs. That is to say, the local aggregation of NRs can be found because the orientational entropy can make the aggregated NRs arrange in the side-to-side parallel manner. In the rigid polymer chain limit (very large bending energy), the rigid polymer chain is stretched and the NRs are well dispersed. As the rigid polymer holds a long persistence length, the NRs can move freely along the stretched polymer chain, and the dispersed conformation of NRs is formed. For the semiflexible polymer chain with a moderate bending energy, the NRs are aggregated in the end-to-end parallel arrangement. Meanwhile, the polymer monomers wrap around those NRs in a well-defined helical structure. The above discussion indicates that the morphologies of NRs are closely related to the conformations of polymer chains. In fact, when a semiflexible polymer chain binds with a large rigid surface, such as nanotube, the helical structure will be formed and it is driven by entropy. The formation of helical structures for a semiflexible polymer chain can induce NRs to form an end-to-end parallel aggregation. The formation of end-to-end parallel arrangement of NR aggregation is driven by the helical structure of semiflexible polymer chain. For the moderate binding energy, the entropy can drive the semiflexible polymer chain to form local helical structure around the NRs. When more NRs are added to the semiflexble polymer chain/NR mixtures, more local helical structures around NRs are formed. Because the movements of NRs binding with the semiflexible chain are nearly free and an end-to-end parallel arrangement of NRs can form more helical structures than the dispersed NRs, the self-assembly of NRs into an end-to-end parallel structure is expected. That is to say, the formation of end-to-end parallel aggregation of NRs is induced by the helix of semiflexible polymers because it can gain more entropies. The self-assembly of a small number of NRs can be well controlled by varying the stiffness of adsorbed polymer chain. This investigation may provide a new pathway to develop smart medium to manipulate the aggreagtion behavior of a few NRs and to construct novel materials with high performance.

Accurate ab initio structural parameters of the diatomic and triatomic van der Waals molecules (11)BNg (X(2)Π, A(2)Σ(+)) and (11)BNg2 (X̃(2)B1), Ng = (4)He, (20)Ne, (40)Ar, (84)Kr, and (132)Xe.

The weakly interacting BNg and BNg2 molecular systems, Ng = He, Ne, Ar, Kr, and Xe, have been thoroughly studied through coupled-cluster RCCSD(T) calculations and large correlation consistent basis sets. For the BNg diatomics, the states examined are the X(2)Π and A(2)Σ(+), and the X̃(2)B1 state for the C2v BNg2 triatomics. A series of corrections render our final results reliable, judging as well from the (limited) experimental numbers available. Both BHe and BHe2 are marginally unbound, whereas the attractive interactions of the BNg X(2)Π states, where Ng = Ne, Ar, Kr, and Xe, are D0 = 19.8, 98.2, 141.9, and 209.1 cm(-1), respectively. For the BRn (Rn = radon) species, an estimated value of interaction energy D0 ≈ 280 cm(-1) is obtained by a D0 versus static polarizability (α) extrapolation. Corresponding atomization energies of the BNg2 (X̃(2)B1) molecules are AE0 = 52.0 (BNe2), 263.4 (BAr2), 384.6 (BKr2), and 576.9 (BXe2) cm(-1).

Through Thickness Residual Stress Measurements by Neutron Diffraction and Hole Drilling in a Single Laser-Peened Spot on a Thin Aluminium Plate

Residual stress measurements are very challenging in thin aluminium plates. Rolling-induced crystallographic texture can lead to an S-shape fit when using the sin2ψ method for surface X-ray diffraction. Peak broadening and missing peaks can also be observed for synchrotron X-ray diffraction with conventional θ/2θ scanning due to texture. In addition, when measuring near the plate surfaces, partially-filled gauge volumes in diffraction experiments will lead to “pseudo-strains”, an apparent shift between measured and actual positions for the diffraction peak. Obtaining a meaningful value of d0 for strain calculations is another issue for diffraction experiments in thin plates. The low thickness also offers challenges for destructive methods including incremental hole drilling, i.e. there is no defined ASTM standard for measuring non-uniform residual stress profile for thin plates. In this work, 2-mm-thick Al2024-T351 plate was investigated for residual stress fields due to laser peening. Neutron diffraction measurements were carried out at POLDI (Pulse Overlap time-of-flight Diffractometer) in PSI, Switzerland and the results are compared with incremental hole drilling.

Electrochemical study and electrodeposition of copper(I) in ionic liquid-reline

The authors made the electrochemical studies on the electrode processes during copper electrodeposition with ionic liquids-reline as an electrolytic medium. Reline is a commercial name for a eutectic mixture of choline chloride and urea(1:2, molar ratio). This new proposed method of copper deposition is an ecological one because the ionic liquids are recyclable, non-volatile and non-toxic. Cyclic voltammetry investigations were conducted at 343 and 353 K in choline chloride-urea(Reline) deep eutectic solvent with single salt CuCl(generally in 0.05–0.38 mol/L concentration range). Electrochemical impedance spectroscopy investigations were conducted in choline chlorideurea ionic liquid with CuCl(0.05 mol/L). We investigated both cathodic and anodic processes of Cu+ ions at different sweep rates in this new electrolytic system based on choline chloride. We have proposed by this an alternative to the classical copper electrodeposition. Coefficient of diffusion, D 0, for the system Reline-CuCl is presented and the value of D 0 is 1.22×10−8 cm2/s.

A united model for the cosmic ray energy spectra and anisotropy in the energy range 100 – 100 000 GeV

We propose a model where a supernova explodes in some vicinity of our solar system (some tens of parsecs) in the recent past (some tens of thousands years) with the energy release in cosmic rays of order of 1051 erg. The flux from this supernova is added to an isotropic flux from other sources. We consider the case where the Sun's location is not in some typical for Our Galaxy average environment, but in the Local Superbubble about 100 pc across, in which the diffusion coefficient D(E) = D0 × E0.6, with the value of D0 ~ 1025 cm2 s−1. We describe the energy dependence of the anisotropy of cosmic rays in the TeV region, together with the observed features of the energy spectrum of protons found in direct measurements. Our model provides a natural explanation to the hardening of the proton spectrum at 200 GeV, together with the observed steepening of the spectrum above 50 TeV.

Wind tunnel study of turbulent flow past an urban canyon model

Modeling dispersion in urban area requires appropriate input parameters, in par- ticular aerodynamic roughness parameters. A low-speed wind tunnel was deployed to study flow patterns over an urban canyon model with three aspect ratios and three flow speeds of 2, 5, and 10m/s with the objective of obtaining these parameters. Flow speed, standard devi- ation, and turbulence intensity profiles were determined with a single directional hot-wire anemometeratseveralpositionsacrosstheurbancanyonmodel.Theaerodynamicparameters u∗, z0,andd0 wereobtainedfromflowspeedprofileviaanon-linearfitafterasuitablechoice of the initial value of d0 for which all aerodynamic parameters converge. Flow speed and standard deviation profiles do not change significantly with the position across the canyon, but are much affected by the free flow speed. The regular way they respond to the free flow speed suggested a normalization for which all profiles collapse onto a single profile, which dependsonlyonthecanyonaspectratio.Thenormalizationcriterionrevealedtobeimportant for obtaining convergent dimensionless profiles. To describe the general profiles characteris- tics a simple new parameterization is proposed, in which a single-valued function (Gaussian curve) describing the flow speed profile is used in a flux-gradient relationship for describing the standard deviation profiles. This parameterization works well down to z/ h ∼ 0.25 -0.50.

Case Selection in Public Management Research: Problems and Solutions

Case Selection in Public Management Research: Problems and Solutions

Impact of dosimetric and clinical parameters on clinical side effects in cervix cancer patients treated with 3D pulse-dose-rate intracavitary brachytherapy

Background and purposeTo assess the association between dosimetric/clinical parameters and gastrointestinal/urinary grade 2–4 side effects in cervix cancer patients treated with 3D pulse dose rate brachytherapy. Materials and methodsThree hundred and fifty-two patients received brachytherapy associated with external-beam radiotherapy (EBRT) for 266 of them; 236 patients underwent surgery. The doses for the most exposed 2, and 0.1cm3 (D2cc and D0.1cc) volumes of the rectum and bladder as well as bladder ICRU point dose (DICRU) were converted into isoeffective doses in 2-Gy fractions. The clinical parameters analyzed were: age, smoking habits, arteritis, diabetes, previous pelvic surgery, FIGO stage, nodal status, pathology, pelvic surgery, EBRT and chemotherapy. Side effects were prospectively assessed using the CTCAEv3.0. Cutoff dose levels were defined separately for patients treated with EBRT and brachytherapy (Group 1) and with preoperative brachytherapy (Group 2). ResultsThe median follow-up was 23.4months. In Group 1 a significant predictive value of rectum D0.1cc and D2cc, bladder D0.1cc and DICRU for gastrointestinal and urinary toxicity was found using as cutoff 83, 68, 109 and 68Gyα/β3. In Group 2 a significant predictive value of bladder D0.1cc, D2cc and DICRU for urinary toxicity was found using as cutoff 141, 91 and 67Gyα/β3, but not for the rectum D0.1cc and D2cc; smoking had a significant predictive value on urinary toxicity. ConclusionsFor patients treated with brachytherapy and EBRT, rectum D0.1cc and D2cc and bladder D0.1cc and DICRU had a predictive value for toxicity. For patients treated with preoperative brachytherapy, bladder D0.1cc, D2cc and DICRU and smoking had a predictive value for urinary toxicity.

Sorting Technique of Cells in Gravure Cylinder Based on Perceptrons Network

This work presents a new class of models for detection technique of cells in gravure cylinder. We apply perceptrons network that belongs to a model of neural network to build up a sorting system of cells in gravure cylinder. Firstly, the cells images are gained in the images capturing device. We have applied the MATLAB image processing software to read the experiment images and histogram equalization. The edge of cells is extracted by using of Sobel operator and Canny operator. We use different thresholds and experimental sigma values that compare to experimental results. It is found that extraction using the Canny operator is better than Sobel operator. Canny edge extraction operator is best when the value of sigma is 16. According to the image used in this research to determine the standard cells carving the value of gaps d0 equals 125, the value of dark tone s0 equals 394, so its standard value of gaps and dark tone are d0 ± 10 and s0 ± 10. The value of gravure outlets gaps and dark tone are measured, while d and s is in the scope of standard range, which the output 1 of the cells determined to pass and the output 0 deemed to fail. Binarization images are obtained through adaptive threshold segmentation, which regards the value of gaps and dark tone as the characteristic value when they start to sorting. Finally, we classify the cells into two classes by using perceptrons network. The experimental results consider neural network model that produce properly sorting and gain true systematization consequences by use of perceptrons network.

Comparative proteomic and radiobiological analyses in human lung adenocarcinoma cells

In clinic, many non-small cell lung cancer (NSCLC) patients receive radiation therapy after chemotherapy failure. However, whether the multidrug resistance (MDR) can elevate the radioresistance (RDR) remains unclear. To evaluate the MDR's effect on the RDR, screen MDR- and RDR-related proteins in human lung adenocarcinoma (HLA) cells and tissues A549, and A549/DDP cells after irradiation were analyzed by colony-forming assay and flow cytometry. Two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) were utilized to identify differentially expressed proteins (DEPs) between them. The value of D0, Dq, and SF2 increased, the mean percentage in G2 phase and apoptosis rate significantly decreased in A549/DDP cells compared with A549 cells. 40 DEP points were found, and among them 27 were identified through proteomics. Four up-regulated proteins (HSPB1, Vimentin, Cofilin-1, and Annexin A4) in MDR cells compared with non-MDR cells, were confirmed by Western blot. Immuno-histochemistry showed that they were also over-expressed in MDR tissues compared with non-MDR counterparts of HLA. These results proved that the MDR in HLA cells and tissues increased the RDR. HSPB1, Vimentin, Cofilin-1, and Annexin A4 are potential biomarkers for predicting HLA response to MDR and RDR, and novel treatment targets of HLA.