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Dependence on the graviton gauge enters the conventional effective field equations because they fail to account for quantum gravitational correlations with the source which excites the effective field and with the observer who measures it. Including these correlations has been shown to eliminate gauge dependence in flat space background. We generalize the technique to de Sitter background for the case of the 1-loop graviton corrections to the exchange potential of a massless, minimally coupled scalar. [ABSTRACT FROM AUTHOR]

To improve the high-temperature erosion wear resistance of 304 stainless steel, this study designed and fabricated bionic samples based on the erosion wear resistance characteristics of the desert scorpion body surface. Uniformly distributed ridged bionic units were fabricated on the surface of 304 stainless steel by laser cladding 25% WC-NiCrBSiFe. The experiments were conducted using self-designed high-temperature erosion wear equipment to compare the erosion rates of bionic and untreated samples from room temperature to 1000ºC. The results showed that the erosion rate of the bionic samples was significantly lower than that of the untreated sample at different temperatures. The erosion rate of bionic units slowly increased from room temperature to 1000ºC, showed a decreasing trend at 400–600ºC, and reached a maximum value at 1000ºC, which is 50% of the untreated sample. The bionic unit's wear mechanism mainly includes chiseling, plowing, and removal of the oxide film, as well as hard phases. Subsequently, the mechanisms of the unit on high temperature erosion wear resistance improvement were suggested: (i) the unique microscopic structure of bionic units with alternating distribution of soft and hard phases can weaken the impact of solid particles, the hard phase resists the plastic deformation and the soft phase absorbs impact energy and hinders crack propagation;(ii) the uniformly distributed ridged units can generate air cushion and shielding effects during high temperature erosion, which can weaken the chiseling and plowing effects of solid particles on the surface of bionic samples. [ABSTRACT FROM AUTHOR]

Maintaining good indoor air quality and thermal comfort is a challenge for naturally ventilated educational buildings, as it can be difficult to achieve both aspects simultaneously. Nonetheless, most of the existing studies only focus on one aspect. To explore the potential of balancing indoor air quality and thermal comfort, both topics must be investigated concurrently. This study assessed indoor air quality and thermal comfort in 32 naturally ventilated classrooms of 16 primary and secondary schools in the Mediterranean climate, based on a large on-site measurement campaign lasting one year that gathered over 460 hours of data. The research investigated occupants' adaptive behaviors, analyzed the actual thermal comfort of around 600 students, and characterized the representative scenarios leading to good and poor indoor air quality and thermal comfort by clustering analysis. The results showed that poor indoor air quality was mainly due to closing windows and doors in winter, while thermal discomfort mainly occurred in summer because of the high indoor temperature. The findings suggested that a proper ventilation protocol is the key to balancing indoor air quality and thermal comfort. [ABSTRACT FROM AUTHOR]

Recent progress on nonlinear sigma models on de Sitter background has permitted the resummation of large inflationary logarithms by combining a variant of Starobinsky’s stochastic formalism with a variant of the renormalization group. We reconsider single graviton loop corrections to the photon wave function, and to the Coulomb potential, in light of these developments. Neither of the two 1-loop results have a stochastic explanation, however, the flow of a curvature-dependent field strength renormalization explains their factors of ln(a). We speculate that the factor of ln(Hr) in the Coulomb potential should not be considered as a leading logarithm effect. [ABSTRACT FROM AUTHOR]

We consider single graviton loop corrections to the effective field equation of a massless, minimally coupled scalar on de Sitter background in the simplest gauge. We find a large temporal logarithm in the approach to freeze-in at late times, but no correction to the feeze-in amplitude. We also find a large spatial logarithm (at large distances) in the scalar potential generated by a point source, which can be explained using the renormalization group with one of the higher derivative counterterms regarded as a curvature-dependent field strength renormalization. We discuss how these results set the stage for a project to purge gauge dependence by including quantum gravitational corrections to the source which disturbs the effective field and to the observer who measures it. [ABSTRACT FROM AUTHOR]

We consider two nonlinear sigma models on de Sitter background which involve the same derivative interactions as quantum gravity but without the gauge issue. The first model contains only a single field, which can be reduced to a free theory by a local field redefinition; the second contains two fields and cannot be so reduced. Loop corrections in both models produce large temporal and spatial logarithms which cause perturbation theory to break down at late times and large distances. Many of these logarithms derive from the “tail” part of the propagator and can be summed using a variant of Starobinsky’s stochastic formalism involving a curvature-dependent effective potential. The remaining logarithms derive from the ultraviolet and can be summed using a variant of the renormalization group based on a special class of curvature-dependent renormalizations. Explicit results are derived at 1-loop and 2-loop orders. [ABSTRACT FROM AUTHOR]

Aim: To investigate the associations of skeletal muscle area and density with coronary atherosclerotic plaques and significant stenosis in asymptomatic adults.Materials and Methods: A total of 243 consecutive subjects who had voluntarily undergone abdominal unenhanced computed tomography (CT) and coronary CT angiography (CCTA) as part of a general health examination were investigated retrospectively. Skeletal muscle area index (SMI) and skeletal muscle density (SMD) was assessed using CT. Coronary atherosclerotic plaques and stenosis on CCTA were evaluated. The associations of low SMI and low SMD with coronary atherosclerotic plaques and significant stenosis were determined by logistic regression analysis.Results: After adjustment for cardiovascular risk factors, there were significant associations of low SMI or low SMD with atherosclerotic plaque, total significant stenosis, and significant stenosis caused by calcified or mixed plaques (for all p<0.05). In addition, multivariate regression analysis also showed that low SMI was independently associated with calcified plaque (p=0.038) and non-calcified plaque (p=0.006), and individuals with low SMD were more likely to have mixed plaque (p=0.001).Conclusion: Assessment of the skeletal muscle on CT help to identify asymptomatic adults at risk for coronary atherosclerosis. [ABSTRACT FROM AUTHOR]

Cosmological Coleman–Weinberg potentials are induced when normal matter is coupled to the inflaton. It has long been known that the corrections from bosonic fields are positive whereas those from fermionic fields are negative. In flat space both take the form ±φ4 ln(φ), and they can be made to cancel by appropriately choosing the coupling constants. In an expanding Universe the bosonic and fermionic results no longer take the same form, although their large field limits do. We choose the coupling constants so that the large field limits cancel, and then follow the deviations which result as inflation progresses. Although the result is not satisfactory we discuss how adding scalars with various conformal couplings likely solves the problem. [ABSTRACT FROM AUTHOR]

Polycrystalline Ba(Ti0.85Sn0.15)O3/Bi1.5Zn1.0Nb1.5O7 (BTS/BZN) heterostructure thin films were deposited on LaNiO3/SiO2/Si substrates by pulsed laser deposition. The leakage mechanisms of the BTS/BZN heterostructure thin films were studied in the temperature range from 303 to 403 K. At a high electric field (>100 kV/cm) and a positive bias, the leakage is dominated by space-charge-limited-current, while Fowler–Nordheim tunneling is the main reason for conduction under a negative bias. At a low electric field, the leakage current is controlled by the Ohmic contact. [ABSTRACT FROM AUTHOR]

The Ba(Ti1-xZrx)O3 (BTZ) system with x≤0.35 has been studied using a combination of x-ray diffraction, dielectric measurements, Raman spectroscopy, and electron diffraction with a view to better understand the changes in structure and correlation length of polar order as a function of composition and temperature. Careful fitting of Raman spectra has confirmed stabilization of the orthorhombic phase at room temperature in x=0.05 with mixed phase (orthorhombic and rhombohedral) present at 80 K. Raman data suggest that the rhombohedral phase is most likely to be present at low temperature for x=0.15 and 0.25 and that only short range polar order evolves in x=0.35. Interpretation of the Raman spectra is in broad agreement with the dielectric data as a function of composition and temperature. Diffuse scatter at room temperature in high order zone axis electron diffraction remains essentially identical for all compositions irrespective of structure and correlation length of polar order. The diffuse maxima are therefore considered not to relate directly to the correlation length of polar order in the BTZ system and therefore do not contribute to the dielectric behavior. [ABSTRACT FROM AUTHOR]

In this study, tin dioxide (SnO2) modified F-TiO2/SiO2 catalysts (F-TiO2/SnO2/SiO2) was prepared by two steps method. The prepared powders were characterized by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Ernmett-Teller (BET), ultraviolet-visible absorption spectroscopy (UV-vis), photoluminescence spectroscopy (PL). The photocatalytic activities was evaluated by degradation ratio of acrylonitrile, which reached 74.0%, that was higher than that of F-TiO2/SiO2 catalysts 60.5 % after irradiation under simulated sunlight for 6 min. A series of characterization showed that the SnO2 modified photocatalysts had small crystal size, large specific surface area, and were easily dispersed uniformly in the reaction system. The photoluminescence (PL) spectra were also slightly weakened, implying that SnO2 modification well inhibited the recombination of electron hole pairs. A red shift of absorption edge occurred implying that the utilization of visible light was effective. [ABSTRACT FROM AUTHOR]

Redox transformations involving quinone/hydroquinone redox pair on a glassy carbon electrode (pristine and modified with poly-3,4-ethylenedioxythiophene film) have been investigated by means of cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Two new mixed-ligand Zn(II) coordination polymers, namely {[Zn(dtb)(1,3-bdc)(H2O)2](H2O)}n (1) and {[Zn1.5(dtb)(1,3,5-btc)(H2O)5](H2O)}n (2) (dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene, 1,3-H2bdc = 1,3- benzenedicarboxylic acid, 1,3,5-H3btc = 1,3,5-benzenetricarboxylic acid) are hydrothermally synthesized and characterized by elemental analyses, infrared spectroscopy, powder and single crystal X-ray diffraction analyses. Both complexes display 1D chain structures. The thermal stabilities and luminescence properties of compounds 1 and 2 are also investigated. Crystal data: 1. C18H18N6O7Zn, Mr = 495.75, triclinic, P-1, a = 10.0820(11) Å, b = 10.1833(11) Å, c = 11.2000(12) Å, α = 80.8680(10)°, β = 73.7290(10)°, γ = 63.4320(10)°, V = 986.52(18) Å3, Z = 2, R(F) = 0.0246, wR(F2) = 0.0664; 2. C19H23N6O12Zn1.5, Mr = 625.49, triclinic, P-1, a = 6.588(4) Å, b = 11.757(7) Å, c = 15.724(9) Å, α = 76.883(6)°, β = 86.094(7)°, γ = 75.989(7)°, V = 1150.8(12) Å3, Z = 2, R(F) = 0.0355, wR(F2) = 0.0822. [ABSTRACT FROM AUTHOR]

Urbanization modifies atmospheric energy and moisture balances, forming distinct features [e.g., urban heat islands (UHIs) and enhanced or decreased precipitation]. These produce significant challenges to science and society, including rapid and intense flooding, heat waves strengthened by UHIs, and air pollutant haze. The Study of Urban Impacts on Rainfall and Fog/Haze (SURF) has brought together international expertise on observations and modeling, meteorology and atmospheric chemistry, and research and operational forecasting. The SURF overall science objective is a better understanding of urban, terrain, convection, and aerosol interactions for improved forecast accuracy. Specific objectives include a) promoting cooperative international research to improve understanding of urban summer convective precipitation and winter particulate episodes via extensive field studies, b) improving high-resolution urban weather and air quality forecast models, and c) enhancing urban weather forecasts for societal applications (e.g., health, energy, hydrologic, climate change, air quality, planning, and emergency response management). Preliminary SURF observational and modeling results are shown (i.e., turbulent PBL structure, bifurcating thunderstorms, haze events, urban canopy model development, and model forecast evaluation). [ABSTRACT FROM AUTHOR]

The high-temperature stability and good mechanical strength of tungsten (W) alloys are highly desirable for a wide range of fusion applications, which can be achieved by dispersion strengthening. In this paper, TaC dispersion effects on the thermal stabilities, tensile properties and thermal shock resistances have been investigated. A hot-rolled W-1.0 wt% TaC plate has been fabricated which contains the high tensile strength and elongation. Nanosized particles in the W matrix improve the recrystallization temperature to about 1400 °C and the ultimate tensile strength to 571 MPa at 500 °C through hindering grain boundary migration, pinning dislocations and refining grains. The effects of edge-localized mode like transient heat events on the rolled and recrystallized W-1.0 wt% TaC alloys were investigated systematically. The cracking threshold (100 shots) at room temperature is in the range of 0.33–0.44 GW/m 2 for the rolled W-1.0 wt% TaC. Recrystallization degrades mechanical strength and makes the material more prone to thermal shock damages. Coarse Ta 2 O 5 and Ta-C x -O y particles are easy to fracture and introduce a preferential crack initiation in W matrix during cyclic heat loads. [ABSTRACT FROM AUTHOR]

In this paper, W-0.5 wt.% Ta-0.01 wt.% C (W-05Ta-001C) alloys were fabricated via a combination of high energy ball milling and subsequent spark plasma sintering. The W-05Ta-001C alloys showed high strength of 565 MPa at 400 °C with a total elongation of 54%. The improved ductility resulted from nanosized TaC precipitation. The microstructure analysis of W-05Ta-001C alloys indicate that the nanosized TaC precipitation uniformly distributed in the grain interior encouraging trapping dislocations. TaC could reduce free oxygen concentration and thus enhance grain boundaries strength by reacting with impurities of oxygen to form compounds of Ta-C x -O y at grain boundaries. The thermal stability of W-05Ta-001C alloys was investigated by analyzing the evolution of hardness based on isochronal annealing tests. The results showed that hardness only slightly decreased with increasing annealing temperature up to 1500 °C, and the recrystallization temperature was about 1600 °C. This good thermal stability is attributed to nanosized TaC dispersion strengthened structures. [ABSTRACT FROM AUTHOR]

Recrystallization and thermal shock fatigue resistance behavior of nanoscale ZrC dispersion strengthened bulk tungsten alloys (W-0.5 wt% ZrC, WZrC) as potential candidates for plasma-facing components were investigated. By employing heat treatments with isochronal experiments, the evolution of the tungsten grain size/orientation, second phase particle distribution, thermal conductivity and mechanical properties were systematically studied. The effects of edge-localized mode like transient heat events on the as-rolled and recrystallized WZrC were investigated carefully. Pulses from an electron beam with durations of 1 ms were used to simulate the transient heat loading in fusion devices. The cracking thresholds, cracking mechanisms and recrystallization under repetitive (100 shots) transient heat loads were investigated. Results indicate that the cracking threshold of all the WZrC samples is 220–330 MW/m 2 (corresponding to a heat load parameter F = 7.0–10.4 MJ/m 2 s 1/2 ) at room temperature and the heat bombardment induced recrystallization occurs at a heat parameter of 10.4 MJ/m 2 s 1/2 . [ABSTRACT FROM AUTHOR]

HfC dispersion strengthened tungsten alloys were prepared by the spark plasma sintering (SPS) and an ordinary sintering followed by swaging, respectively. The HfC content is optimized as 0.5 wt% through spark plasma sintering (SPS) processing. The thermal stability, thermal conductivity and mechanical properties of swaged W-0.5 wt%HfC (WHC05) alloys were systematically investigated. Grain of swaged WHC05 has an obvious round bar shaped morphology with an average diameter of 24.5 μm and an average length of 187 μm, respectively, which keeps stability with increasing annealing temperature up to 1400 °C. The ductile-brittle transition temperature of swaged WHC05 is about 250 °C, much lower than that of SPSed WHC05 samples (∼500 °C). The ultimate tensile strength of swaged WHC05 alloys annealed at 1200 °C has no significant drops in a wide tested temperature range from 300 °C to 800 °C. The thermal conductivity of swaged WHC05 annealed at 1200 °C is up to 174 W/m·K at room temperature and always larger than 137 W/m·K from RT to 500 °C, which is much higher than that of the unannealed one and just the same with ITER grade W. [ABSTRACT FROM AUTHOR]

Respiratory motion is one major complicating factor in many image acquisition applications and image-guided interventions. Existing respiratory motion estimation and compensation methods typically rely on breathing motion models learned from certain training data, and therefore may not be able to effectively handle intra-subject and/or inter-subject variations of respiratory motion. In this paper, we propose a respiratory motion compensation framework that directly recovers motion fields from sparsely spaced and efficiently acquired dynamic 2-D MRIs without using a learned respiratory motion model. We present a scatter-to-volume deformable registration algorithm to register dynamic 2-D MRIs with a static 3-D MRI to recover dense deformation fields. Practical considerations and approximations are provided to solve the scatter-to-volume registration problem efficiently. The performance of the proposed method was investigated on both synthetic and real MRI datasets, and the results showed significant improvements over the state-of-art respiratory motion modeling methods. We also demonstrated a potential application of the proposed method on MRI-based motion corrected PET imaging using hybrid PET/MRI. [ABSTRACT FROM AUTHOR]

In this paper, hot rolled W-0.5 wt% TiC alloys are fabricated via a combination of powder metallurgy and subsequent hot rolling with 65% thickness reduction. The as-rolled alloys show high strength of 789 MPa at 200 °C with a total elongation of 4.8%. We have explored the mechanical properties and thermal stability of W-0.5 wt% TiC alloys after annealing at various temperature. The corresponding results show that hardness and fracture strength slightly decrease with increased annealing temperature up to 1500 °C owing to recovery. While after annealing at 1600 °C for 1 h, the fracture strength of W-0.5 wt% TiC alloys decreases significantly due to full recrystallization and grain growth. The thermal conductivity increases with increased annealing temperature. The observed incubation time for recrystallization and the corresponding recrystallization thermal activation energy (~612 kJ/mol) for this rolled plates indicate a sufficient thermal stability at service temperature below 1200 °C. This good thermal stability is attributed to the nanosized TiC dispersion strengthened structures. [ABSTRACT FROM AUTHOR]

This study sampled five plant species and adjoining sediments from the Qi’ao (Zhuhai) and Nansha (Guangzhou) coastal wetlands located in the Pearl River estuary, South China. The compositions of stable carbon and nitrogen isotopes as well as the content of carbon and nitrogen in the samples were analysed. Differences in carbon/nitrogen (C/N) ratio, and habitat feature were compared between exotic plants (Spartina alterniflora,Sonneratia apetala, andLaguncularia racemosa) and native mangroves (Aegiceras corniculatumandAcrostichum aureum). The results showed that for Qi’ao, which is nearer the sea, the conductivity of the sediments at this location was approximately two times higher than that at Nansha (more inland). The composition of bothδ13C andδ15N in sediments was also higher at Qi’ao (−26.52‰ to −23.83‰ and 6.25‰ to 11.53‰, respectively) as compared to Nansha (−29.30‰ to −27.43‰ and 3.34‰ to 4.73‰, respectively). Overall, the exotic plantsS. alternifloraandS. apetalaat Qi’ao andS. apetalaandL. racemosaat Nansha had an averageδ15N composition significantly higher than that of the native plantsA. corniculatumandA. aureum. This suggests that the three exotic plants employ a different mechanism ofδ15N storage and utilisation as compared to the two native mangrove species, which may result in changes in ecological and biogeochemical processes in these coast wetlands. [ABSTRACT FROM PUBLISHER]

The mechanical properties and thermal conductivity of W-0.5 wt.% TaC alloys prepared by spark plasma sintering as well as ordinary sintering followed by hot rolling and annealing treatment, respectively, were investigated. Tensile tests indicate that below 600 °C there is no tensile plastic deformation while at 700 °C the total elongation of spark plasma sintered (SPSed) W-0.5 wt.% TaC is up to 36%, which is about 3.3 times that of spark plasma sintered W samples. In contrast, the tensile strength and total elongation of rolled W-0.5 wt.% TaC are 717 MPa and 10.7% at 250 °C, respectively. The ductile-brittle transition temperature (DBTT) of rolled W-0.5 wt.% TaC is between 200 °C and 250 °C, about 300 °C lower than that of spark plasma sintered W-0.5 wt.% TaC (~ 600 °C). Annealing decreases the DBTT (~ 200 °C) and improves thermal conductivity from 175 to 186 W/m·K at room temperature. Microstructure analyses indicates that TaC could purify and strengthen grain boundaries by capturing impurity oxygen in tungsten to form Ta 2 O 5 . The results indicate that strength, ductility and thermal conductivity can be improved by purifying, hot rolling and subsequent annealing. [ABSTRACT FROM AUTHOR]

Three Cu(II) coordination polymers, namely {[Cu(Dtb)(HO)](SO)(HO)} ( I), {[Cu(Dtb)(CO)(HO)](HO)} ( II), and {[Cu(Dtb)(NO)](NO)(HO)} ( III) (Dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene), have been synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectra, and single-crystal X-ray diffraction (CIF file CCDC nos. 1001347 ( I); 1001348 ( II); 1001349 ( III)). Complex I is a 1D double-chain structure, Dtb acts as μ-bridging ligand and SO does not participate in coordination. In contrast, complex II shows a 1D single-chain, in which Dtb shows μ-bridges mode and CO occupies two coordination positions. In complex III, NO shortens the distance of two Cu(II) centers by bridging coordination interaction, so Dtb becomes μ-bridges linker to extend the Cu(II) centers to the resulting 2D layer. [ABSTRACT FROM AUTHOR]

Heat shock protein (Hsp)90 regulates many key pathways in oncogenesis, including Akt and mammalian target of rapamycin (mTOR). The strengths of disruption of Hsp90 in cancer therapy include their versatility in inhibiting a wide range of oncogenic pathways. The present study demonstrated that synuclein γ (SNCG) protects the functions of Akt and mTOR in the condition when the function of Hsp90 is blocked. Disruption of Hsp90 abolished Akt activity and mTOR signaling. However, expression of SNCG restored Akt activity and mTOR signaling. SNCG bound to Akt and mTOR in the presence and absence of Hsp90. Specifically, the C-terminal (Gln106-Asp127) of SNCG bound to the loop connecting αC helix and β4 sheet of the kinase domain of Akt. SNCG renders resistance to 17-AAG-induced apoptosis both in vitro and in tumor xenograft. A clinical follow-up study indicates that patients with an SNCG-positive breast cancer have a significantly shorter disease-free survival and overall survival than patients with SNCG-negative tumors. The present study indicates that SNCG protects Hsp90 client proteins of Akt and mTOR, and renders drug resistance to Hsp90 disruption. [ABSTRACT FROM AUTHOR]

We reported the realization of a 174Yb+–113Cd+ bi-species Coulomb crystal comprising 174Yb+, a heavier ion, as coolant and verified the potential of applying a coolant ion with a greater mass than the clock ion to sympathetically cooled microwave frequency standard. The two species of massive ions stably trapped in a Paul trap make up this large two-component crystal. The 113Cd+ ions are trapped in the center, which reduces considerably RF heating and excess micro-motion to which the 113Cd+ ions are subjected. Under this scheme, the uncertainty due to the second-order Doppler effect is reduced to 5 × 10 − 16 , which represents an order of magnitude improvement over sympathetic cooled 40Ca+–113Cd+ crystal. The second-order Zeeman frequency shift, which contributes the largest term of the systematic frequency shifts to the microwave ion frequency standard, is estimated to be as low as 7.133 × 10 − 13 corresponding to the low value of the operating magnetic field. The relevant AC Stark shift uncertainty is estimated to be 4 × 10 − 19 . These results demonstrate that using a heavier coolant ion is far superior and confirm the feasibility of a sympathetic-cooled cadmium-ion microwave clock system employing a 174Yb+–113Cd+ bicrystal. [ABSTRACT FROM AUTHOR]

The 1-(diphenylmethylene)-2-(thiazolo[4,5-b]pyridin-2-yl)hydrazine compound ( IV) is synthesized based on a 3-amion-2-chloropyridine precursor and characterized by single crystal X-ray diffraction. The structural analysis reveals that compound IV belongs to the monoclinic system, space group P2/ c, a = 11.869(5) Å, b = 13.155(6) Å, c = 10.970(5) Å, β = 102.431(5)°, V = 1672.6(12) Å, Z = 4. In the crystal structure, the molecular species are linked by intermolecular N-H...N hydrogen bonds into onedimensional chains. [ABSTRACT FROM AUTHOR]

Highlights: [•] We studied the effects of sugars adding on the stability of nanoemulsions during freeze-drying. [•] Addition of sugars protected emulsions from coalescence during freezing step. [•] Lactose and trehalose showed better protecting effects than maltodextrins. [•] Concentration and types of protectants are critical for drying of nanoemulsions. [ABSTRACT FROM AUTHOR]

The thermo-physical properties for four rock types (granite, granodiorite, gabbro, and garnet amphibolite) from room temperature to 1,173 K were investigated. Thermal diffusivity and specific heat capacity were measured using the laser-flash technique and heat flux differential scanning calorimetry, respectively. Combined with the density data, rock thermal conductivities were calculated. Rock thermal diffusivity and conductivity decrease as the temperature increases and approach a constant value at high temperatures. At room temperature, the measured thermal conductivity is consistently near or lower than the calculated conductivity using the mineral series model, which suggests that real thermal conduction is more complicated than is depicted in the model. Therefore, in situ measurement remains the best method for accurately obtaining thermal conductivity for rocks. [ABSTRACT FROM AUTHOR]

The BiFeO3 films were deposited on the SrTiO3 (001) substrates via tuning the thickness of the SrRuO3 (SRO) bottom electrode by pulsed laser deposition. The macroscopic ferroelectric and dielectric properties were dramatically impacted by the various nanoscale domain structures for both films due to the tunable SRO thickness. The nanoscale domain switching behaviors for both films were investigated via piezoresponse force microscopy, and results suggest that the domain structure could be changed by tuning the strain state. The surface potential investigation indicates that strain helps increase data storage density and stability. [ABSTRACT FROM AUTHOR]

We explicitly work out the de Sitter breaking contributions to the recent solution for the de Donder gauge graviton propagator on de Sitter. We also provide explicit power series expansions for the two structure functions, which are suitable for implementing dimensional regularization. And we evaluate the coincidence limit of the propagator. [ABSTRACT FROM AUTHOR]

We construct the graviton propagator on de Sitter background in exact de Donder gauge. We prove that it must break de Sitter invariance, just like the propagator of the massless, minimally coupled scalar. Our explicit solutions for its two scalar structure functions preserve spatial homogeneity and isotropy so that the propagator can be used within the larger context of inflationary cosmology; however, it is simple to alter the residual symmetry. Because our gauge condition is de Sitter invariant (although no solution for the propagator can be) renormalization should be simpler using this propagator than one based on a noncovariant gauge. It remains to be seen how other computational steps compare. [ABSTRACT FROM AUTHOR]

A new zinc(II) complex Zn(HPimda)] · HO ( I), where HPimda = 2-Propyl-1 H-imidazole-4, 5-dicarboxylic acid, has been synthesized and characterized by elemental analysis, IR spectroscopy and X-ray single-crystal diffraction. It crystallizes in the triclinic system, space group P $\bar 1$, with a = 8.397(3), b = 11.271(4), c = 12.312(5)Å, α = 70.432(5), β = 70.984(5), γ = 74.897(5)°, V = 1022.9(7) Å, M = 475.71, Z = 2, ρ = 1.695 g/cm, F(000) = 488, μ = 1.151 mm, R = 0.0659 and Rw =0.1525 for 3769 observed reflections. The hydrogen bonding derived from the coordinated waters connects the mononuclear zinc complex units into a one-dimensional chain, and these chains are further linked by intermolecular hydrogen bonds into a 2D supramolecular network. Complex I also displays strong photoluminescence properties in the liquid state at room temperature. [ABSTRACT FROM AUTHOR]

Two new copper( II) complexes ( I, II) with benzimidazole ligands have been synthesized and characterized by elemental analysis and X-ray single-crystal diffraction. Compound I is triclinic, P $\bar 1$ , a = 11.4205(6), b = 13.0956(7), c = 18.2305(9) Å, α = 85.960(1)°, β = 80.388(0)°, γ = 77.517(1)°, V = 2623.0(2) Å, Z = 2; compound II is monoclinic, C2/ c, a = 24.2684(11), b = 17.5247(8), c = 19.3149(15) Å, β = 122.710(1)°, V = 6911.9(7) Å, Z = 4. In both compounds, Cu(II) atoms are coordinated by four benzimidazole nitrogen atoms in a slightly distorted tetrahedral fashion. [ABSTRACT FROM AUTHOR]

Bi(Fe0.5Sc0.5)O3–PbTiO3 (BSFPT) films have been fabricated on Pt/TiO2/SiO2/Si substrates by pulsed laser deposition. The microstructure, chemical state, ferroelectric and magnetic properties were investigated. The leakage mechanism of the BSFPT thin film showed bulk limited, space charge limited current characteristics from 200 to 220K, whereas bulk limited Poole–Frenkel emission and interface limited Fowler–Nordheim tunneling coexisted at temperatures between 250 and 300K. The substitution of Sc3+ for Fe3+ ions was considered to improve the valence stability and, therefore, decrease the overall leakage current. [ABSTRACT FROM AUTHOR]

Just because the propagator of some field obeys a de Sitter invariant equation does not mean it possesses a de Sitter invariant solution. The classic example is the propagator of a massless, minimally coupled scalar. We show that the same thing happens for massive scalars with MS2<0 and for massive transverse vectors with MV2≤-2(D-1)H2, where D is the dimension of space-time and H is the Hubble parameter. Although all masses in these ranges give infrared divergent mode sums, using dimensional regularization (or any other analytic continuation technique) to define the mode sums leads to the incorrect conclusion that de Sitter invariant solutions exist except at discrete values of the masses. [ABSTRACT FROM AUTHOR]

In recent years, immense interest has been paid to biomolecular architecture with the aim of protein assembly in two dimensions on solid substrates, and the construction of clay-protein ultrathin films (CPUFs). An overview is provided of recent research on hybrid ultrafilms or nanofilms of clay mineral layers and protein molecules. Two techniques, layer-by-layer (LbL) assembly and Langmuir-Blodgett (LB), are presented. The films are characterised by UV-visible spectroscopy and atomic force microscopy (AFM). The amount of proteins incorporated in the films is obtained from UV-visible spectra. Film formation in the LB trough is studied by following the surface pressure versus time curves and the surface pressure versus area isotherms. With AFM the individual clay mineral layers and aggregates of protein molecules are resolved. [ABSTRACT FROM AUTHOR]

Two new zinc(II) complexes have been synthesized and studied by single crystal X-ray diffraction method: [Zn(L1)Cl2]·2DMF ( 1) and [Zn(L2)Cl2]·DMF ( 2) (L1 = 3,3′-bis(2-benzimidazolyl)-2,2′-dipyridine, L2 = 3,3′-bis[2-bis(2-ethylbenzimidazolyl)]-2,2′-dipyridine). Compound 1 is monoclinic, C2/ c, a = 23.142(3) Å, b = 11.845(1) Å, c = 14.735(3) Å; compound 2 is orthorhombic, C2221, a = 12.140(7) Å, b = 16.283(9) Å, c = 16.51(1) Å. In both compounds, Zn(II) cations are coordinated by two chlorine atoms and two benzimidazole nitrogen atoms in a slightly distorted tetrahedron fashion. Structural features responsible for fluorescent properties of the complexes are discussed. [ABSTRACT FROM AUTHOR]

We demonstrate that certain gauge fixing functionals cannot be added to the action on backgrounds such as de Sitter, in which a linearization instability is present. We also construct the field-dependent gauge transformation that carries the electromagnetic vector potential from a convenient, non-de Sitter invariant gauge to the de Sitter invariant, Lorentz gauge. The transformed propagator agrees with the de Sitter invariant result previously found by solving the propagator equation in Lorentz gauge. This shows that the gauge transformation technique will eliminate unphysical breaking of de Sitter invariance introduced by a gauge condition. It is suggested that the same technique can be used to finally resolve the issue of whether or not free gravitons are de Sitter invariant. [ABSTRACT FROM AUTHOR]

This article presents a study which examined the nonenzymatic browning (NEB) rates of amorphous, carbohydrate-based, freeze-dried and spray-dried food model systems with L-lysine and D-xylose. The test results showed that the physical structure food model systems and water sorption qualities are affected by different drying methods. These findings can be used in food processing to restrict potentially damaging changes or to allow color and flavor formation by NEB reaction.

A new process for fabrication of piezoelectric micro-cantilever arrays with PZT thin film for micro or nano range actuation has been developed. By choosing different DRIE etching process, 2 kinds of microcantilever can be fabricated and also we can almost fabricate membrane PZT cantilever with 100% yield, which is impossible in other normal fabrication process due to the over etching of the silicon resulting in some cantilever broken. Film annealing temperature and time are critical to the preparation of the sol-gel PZT thin film. The fabrication process of micro-cantilever arrays in planar structure will be presented. Key issues on the fabrication of the cantilever are: the compatible etching process of PZT thin film, the compensation of thin film stress in all layers to obtain a flat multilayer structure. [ABSTRACT FROM AUTHOR]

The YWK-II component of human sperm membrane is related to the βA4-amyloid precursor protein (APP) of Alzheimer's disease. A yeast 2-hybrid system was used to screen a mouse testis cDNA expression library for potential ligands capable of interacting with the extracellular domain of the YWK-II component. One of the bound proteins was identified as hDIA1, which has 96% identity with p140mDia. These proteins are members of the formin homology family and participate in cytokinesis and organization of the actin cytoskeleton. By interacting with these diaphanous proteins, the YWK-II component may be involved in germ cell differentiation and in the structural formation of the acrosome. [ABSTRACT FROM AUTHOR]

Serum was obtained from an infertile woman having antibodies with sperm agglutinating activity. The antibodies interacted with a human sperm membrane protein (hSMP-1) with an estimated M[sub r] of 55 kD. The gene (HSD-1) coding hSMP-1 was isolated from a human testis cDNA expression library and assigned the accession number U12978. The cDNA was conjugated to a prokaryotic expression vector to construct the recombinant vector, pRSET-HSD-I, which was expressed in Escherichia coli. The recombinant hSMP-1 was isolated and used to immunize rabbits to raise polyclonal antibodies. Using an immunocytochemical technique, hSMP-1 protein was immunolocalized in germ cells of human testis at all stages of spermatogenesis. mRNAs were prepared from 16 different human tissues and analyzed by Northern blot using HSD-1 as probe. A positive reaction was elicited only with testis mRNA. The present findings suggest that the expression of hSMP-1 gene is testis-specific and occurs during the early stages of germ cell differentiation. In a comparative study, the location of the hSMP-1 protein in sperm and in germ cells of the seminiferous tubules of rats was determined. The target antigen was immunolocated on the head and tail of rat sperm and in late spermatids and spermatozoa of rat testis. These results suggest that, in the rat, the HSD-1 gene is expressed during spermiogenesis. [ABSTRACT FROM AUTHOR]

This work described an experimental investigation on the recrystallization behaviors of the hot-rolled particle strengthened W (PSW) material. Upon annealing, the three processes, that is, recovery, recrystallization and grain growth, proceed in a discontinuous fashion for our PSW material, and two or more processes could simultaneously occur in local regions. At an annealing temperature spanning from 1300 °C to 1500 °C, recovery is in the dominant position which is verified by deformed grains over half of the whole, accompanying with a gentle decrease in hardness. Meanwhile, recrystallization nucleation, primary recrystallization and abnormal grain growth is identified at 1300 °C, 1400 °C and 1500 °C, respectively. Further increasing the annealing temperature to 1600 °C and 1700 °C, normal grain growth takes precedence over recovery, along with a marked reduction in hardness. TEM observations show that owing to microstructural heterogeneity induced by particle dispersion, local regions have an advantage in terms of strain energy storage over other regions during hot rolling, enabling a preferential recrystallization nucleation at 1300 °C; whereas nanosized TiC particles are capable of inhibiting grain growth at elevated temperature, and thus retard the recrystallization rate. In addition, our as-rolled PSW material exhibits a different texture, and the dominant α-fiber of {100}〈011〉 and {112}〈1−10〉 transforms into γ-fiber texture of {111}〈011〉 and {111}〈−1−12〉 during recrystallization. • A discontinuous recrystallization process was revealed in the material. • The unique recrystallization behavior stems from microstructure heterogeneity. • Significant texture evolution does occur during the recrystallization process. [ABSTRACT FROM AUTHOR]

A truncated cDNA coding a rabbit epididymal protein (BE-20) was identified in a previous study. In the present study the full-length cDNA was isolated by the method of rapid amplification of cDNA ends. The BE-20 cDNA consisted of 585 bp with a poly(A) tail of 26 residues and an open reading frame composed of 369 bp encoding a deduced polypeptide containing 123 amino acid residues with a calculated molecular mass of 13 kDa. The N-terminus contained a leucine-rich segment. BE-20 cDNA has about 76.8% homology with the HE4 gene of human epididymis. Northern blot analysis of mRNAs prepared from 17 different human tissues was performed using as probe a 0.5-kb DNA fragment corresponding to a segment of BE-20 cDNA. Positive reaction was elicited only with epididymal mRNA. A DNA fragment corresponding to a section of the open reading frame of BE-20 cDNA was cloned in Escherichia coli under the control of the T7 promoter. The cellular content of the expressed recombinant protein comprised about 55% of the total protein. The chromatographically purified bacterial product migrated as a single band with an estimated Mr of 15kDa on analysis by SDS-PAGE. In conclusion, BE-20 cDNA is expressed only in the epididymis. It is structurally related to the four-disulfide core family of extracellular proteinase inhibitors and may be involved in sperm maturation. [ABSTRACT FROM AUTHOR]

Abstract Understanding Cladium jamaicense (sawgrass) seedling establishment is an important component of an Everglades restoration program because the degree of sawgrass recovery and concurrent Typha domingensis (cattail) decline will be used to evaluate restoration success. To understand sawgrass recovery at locations with increased soil nutrients, we tested the effects of transplanting sawgrass seedlings to pots at different densities and investigated how nutrient additions affect seedling growth. Survivorship of seedlings transplanted into moist commercial potting soil at three densities ranged from 61% to 95%. After 6 months, maximum survivorship (90%) occurred at medium densities (2–4 seedlings per pot 16 cm in diameter). Nutrient additions, totaling 6.5 N g/m2 , 9.8 P g/m2 , 6.5 g/m2 , were applied approximately 4 months after seedlings were transplanted. The biomass of the plants receiving nutrient additions (pulsed) was significantly higher (by over 30%) than plants with no nutrient addition (control). Photosynthetic rates for nutrient-enriched plants (measured 6-weeks after the nutrient additions) were significantly greater (by 32–45%) than for control plants. Instantaneous leaf water use efficiency increased significantly (by more than 20%) in pulsed plants. The results suggest that preventing root damage is crucial for the success of transplanted sawgrass seedlings and that nutrient additions enhanced seedling growth. [ABSTRACT FROM AUTHOR]