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This paper discusses the influence of the chemical composition on the microstructure, mechanical and corrosion properties of mechanically alloyed and sintered (Mg-4Y-5.5Dy-0.5Zr)- x wt.% HA composites. Mechanical alloying for 25 h of the Mg-4Y-5.5Dy-0.5Zr composition, followed by sintering under argon at 550 °C for 2 h, led to the formation of a bulk alloy with an ultrafine grained microstructure. With the increase of the hydroxyapatite content in the (Mg-4Y-5.5Dy-0.5Zr)- x wt.% HA composite, a reduction of the grain sizes of the bulk material was noticeable. In the case of the bulk (Mg-4Y-5.5Dy-0.5Zr)-10 wt.% HA composite, the grain sizes of approx. 60 nm have been recorded by atomic force microscopy. The final microstructure of the synthesized composites strongly influenced the mechanical and corrosion properties. The Mg-4Y-5.5Dy-0.5Zr alloy was characterized by higher average values of Young's modulus (36.6 GPa). In the case of the (Mg-4Y-5.5Dy-0.5Zr)-5 wt.% HA scaffolds with the porosity of 48%, the Young's modulus was equal to 7.1 GPa. The (Mg-4Y-5.5Dy-0.5Zr)-10 wt.% HA composite was more corrosion resistant ( I = 5.849 × 10 A cm, E = −1.565 V versus SCE) than Mg-4Y-5.5Dy-0.5Zr alloy ( I = 4.838 × 10 A cm, E = −1.555 V versus SCE). The influence of hydrofluoric acid treatment on the corrosion behavior of the (Mg-4Y-5.5Dy-0.5Zr)-5 wt.% HA composite was also investigated. The electrochemical test showed that the corrosion resistance of fluoride-treated specimens was higher, compared with the untreated samples in the Ringer's solution. In conclusion, fluoride-treated (Mg-4Y-5.5Dy-0.5Zr)-HA composites are biodegradable materials with adjustable mechanical and corrosive properties. [ABSTRACT FROM AUTHOR]

To address the invasion of non-native Phragmites in the Great Lakes, researchers at the U.S. Geological Survey-Great Lakes Science Center partnered with the Great Lakes Commission in 2012 to establish the Great Lakes Phragmites Collaborative (GLPC). The GLPC is a regional-scale partnership established to improve collaboration among stakeholders and increase the effectiveness of non-native Phragmites management and research. Rather than forming a traditional partnership with a narrowly defined goal, the GLPC follows the principles of collective impact to engage stakeholders, guide progress, and align resources to address this complex, regional challenge. In this paper, the concept and tenets of collective impact are described, the GLPC is offered as a model for other natural resource-focused collective impact efforts, and steps for establishing collaboratives are presented. Capitalizing on the interactive collective impact approach, the GLPC is moving toward a broadly accepted common agenda around which agencies and individuals will be able to better align their actions and generate measureable progress in the regional campaign to protect healthy, diverse ecosystems from damage caused by non-native Phragmites. [ABSTRACT FROM AUTHOR]

We hypothesize that bacterial endophytes may enhance the competitiveness and invasiveness of Phragmites australis. To evaluate this hypothesis, endophytic bacteria were isolated from P. australis. The majority of the shoot meristem isolates represent species from phyla Firmicutes, Proteobacteria, and Actinobacteria. We chose one species from each phylum to characterize further and to conduct growth promotion experiments in Phragmites. Bacteria tested include Bacillus amyloliquefaciens A9a, Achromobacter spanius B1, and Microbacterium oxydans B2. Isolates were characterized for known growth promotional traits, including indole acetic acid (IAA) production, secretion of hydrolytic enzymes, phosphate solubilization, and antibiosis activity. Potentially defensive antimicrobial lipopeptides were assayed for through application of co-culturing experiments and mass spectrometer analysis. B. amyloliquefaciens A9a and M. oxydans B2 produced IAA. B. amyloliquefaciens A9a secreted antifungal lipopeptides. Capability to promote growth of P. australis under low nitrogen conditions was evaluated in greenhouse experiments. All three isolates were found to increase the growth of P. australis under low soil nitrogen conditions and showed increased absorption of isotopic nitrogen into plants. This suggests that the Phragmites microbes we evaluated most likely promote growth of Phragmites by enhanced scavenging of nitrogenous compounds from the rhizosphere and transfer to host roots. Collectively, our results support the hypothesis that endophytic bacteria play a role in enhancing growth of P. australis in natural populations. Gaining a better understanding of the precise contributions and mechanisms of endophytes in enabling P. australis to develop high densities rapidly could lead to new symbiosis-based strategies for management and control of the host. [ABSTRACT FROM AUTHOR]

80-μm-thick nanostructured coatings consisting of a Ni solid solution, NiSn, NiSn, and metastable NiSn intermetallic phases were deposited via supersonic cold spraying onto inconel 718 alloy substrates. These coatings have complex nanostructured metallurgical phases as revealed by transition electron microscopy, scanning electron microscopy, and x-ray diffraction techniques. Their mechanical properties were determined by nanoindentation measurements. Furthermore, the wear behavior of these nanostructured sprayed coatings was compared to the one of the industrial bulk or sprayed coated benchmark materials. It was found that the nanostructured coatings exhibit higher wear resistance than the industrial benchmarks, thanks to an appropriate balance of hard intermetallic phases and soft Ni matrix, as well as to their nanostructuring. Their frictional characteristics under reciprocating sliding are mainly determined by the formation of an oxide-based tribo-layer, which was analyzed by x-ray photoelectron spectroscopy. The role of intermetallic phases in these coatings on the friction and wear is also discussed. [ABSTRACT FROM AUTHOR]

The skeletal muscle injury triggers the inflammatory response which is crucial for damaged muscle fiber degradation and satellite cell activation. Immunodeficient mice are often used as a model to study the myogenic potential of transplanted human stem cells. Therefore, it is crucial to elucidate whether such model truly reflects processes occurring under physiological conditions. To answer this question we compared skeletal muscle regeneration of BALB/c, i.e. animals producing all types of inflammatory cells, and SCID mice. Results of our study documented that initial stages of muscles regeneration in both strains of mice were comparable. However, lower number of mononucleated cells was noticed in regenerating SCID mouse muscles. Significant differences in the number of CD14-/CD45+ and CD14+/CD45+ cells between BALB/c and SCID muscles were also observed. In addition, we found important differences in M1 and M2 macrophage levels of BALB/c and SCID mouse muscles identified by CD68 and CD163 markers. Thus, our data show that differences in inflammatory response during muscle regeneration, were not translated into significant modifications in muscle regeneration. [ABSTRACT FROM AUTHOR]

In this paper we seek to enhance the understanding of the structure of the fixed charge transportation problem (FCTP) and to demonstrate the relationship between fixed charge problems and fractional polynomial functions. We provide a new approach for approximating and solving the FCTP by developing novel fractional polynomial approximations for the objective function to obtain lower and upper bounds for the optimal solution. In addition, the lower bound proposed in the paper can be used to obtain superior initial or starting conditions for any established branch-and-bound or iterative algorithm to accelerate convergence to the optimal FCTP solution. [ABSTRACT FROM AUTHOR]

Copyright of Der Orthopäde is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

soil survey was performed to determine the levels, distributions and sources of 6 polycyclic aromatic hydrocarbons (PAHs) in 9 selected soil environments in Esbjerg, Denmark. In all, 24 soil samples were collected and the PAHs present were extracted with dichloromethane and analysed using GC/MS/MS with ion trap detector (TCD). There were elevated levels of the individual as well as the total PAHs in the soil samples and also, all 6 PAHs were present in all the soil samples. The most abundant components were fluoranthene, benzo(b)fluoranthene and benzo(a)pyrene. The average sum of the 6 PAHs in all soil samples was 2.5 mg.kg, with range from 0.24 to 7.6 mg kg. The total mean PAH concentration obtained was 1.67 times higher than the total limit set by the Danish Environmental Protection Agency (DEPA) whiles the mean benzo(a)pyrene (BaP) concentration (0.6 mg kg) also 6 times the Soil Quality Criteria (Human Health) (0.1 mg kg) by DEPA and 2 times the Maximum Permissible Concentrations (0.26 mg kg) by the Netherlands for BaP. This shows that there are elevated levels of PAH deposition on the Esbjerg soil environment which needs an urgent attention. The diagnostic ratios and the correlation analysis identified mixed petrogenic and pyrogenic sources as the main contributors of PAHs on the Esbjerg environment. [ABSTRACT FROM AUTHOR]

Objective:The aim of this study was to evaluate the usefulness of maternal serum and vaginal fluid C-reactive protein (CRP) determinations in the prediction of neonatal congenital infection.Study Design:Fifty women between 24 and 36 weeks gestation, complicated by preterm premature rupture of membranes (pPROM), were divided into two groups according to the presence (n=14) or absence (n=36) of early-onset newborns' infection.Result:Maternal serum and vaginal fluid CRP concentrations were comparable between both groups. Serum CRP levels 10 and 15 mg l-1 predicted neonatal infection with a sensitivity of 47 and 47%, specificity of 63 and 76%, positive predictive value (PPV) of 38 and 47%, and negative predictive value (NPV) of 72 and 76%, respectively. The cutoff value of vaginal CRP 2.4 mg l-1 predicted infection with a sensitivity of 71%, specificity of 47%, PPV of 34%, and NPV of 81%. Receiver-operating characteristic curve analysis revealed that the predictive performance of CRP was poor.Conclusion:Maternal serum and vaginal fluid CRP determinations after pPROM are of poor predictive value in neonatal early-onset infection prediction. [ABSTRACT FROM AUTHOR]

We report preliminary large scale ab initio calculations of ground and excited states of 16O using quantum chemistry inspired coupled cluster methods and realistic two-body interactions. By using the renormalized Hamiltonians obtained with a no-core G-matrix approach, we obtain the virtually converged results at the level of two-body interactions. Due to the polynomial scaling with the system size that characterizes coupled cluster methods, we can probe large model spaces with up to seven major oscillator shells, for which standard non-truncated shell-model calculations are not possible. [ABSTRACT FROM AUTHOR]

The method of moments of coupled-cluster equations (MMCC), which provides a systematic way of improving the results of the standard coupled-cluster (CC) and equation-of-motion CC (EOMCC) calculations for the ground- and excited-state energies of atomic and molecular systems, is described. The MMCC theory and its generalized MMCC (GMMCC) extension that enables one to use the cluster operators resulting from the standard as well as nonstandard CC calculations, including those obtained with the extended CC (ECC) approaches, are based on rigorous mathematical relationships that define the many-body structure of the differences between the full configuration interaction (CI) and CC or EOMCC energies. These relationships can be used to design the noniterative corrections to the CC/EOMCC energies that work for chemical bond breaking and potential energy surfaces of excited electronic states, including excited states dominated by double excitations, where the standard single-reference CC/EOMCC methods fail. Several MMCC and GMMCC approximations are discussed, including the renormalized and completely renormalized CC/EOMCC methods for closed- and open-shell states, the quadratic MMCC approaches, the CI-corrected MMCC methods, and the GMMCC approaches for multiple bond breaking based on the ECC cluster amplitudes. [ABSTRACT FROM AUTHOR]

The recently extended imaging mode of dynamic Secondary Ion Mass Spectroscopy as well as its depth profiling variant were used to study three-dimensional structures in a phase-separating polymer blend film. Formation of layered morphology and its further reorganisation into columns were observed in a system confined by symmetric flat surfaces. The integral-geometry-based morphological image analysis provided a quantitative description of the evolution of the phase morphology. [ABSTRACT FROM AUTHOR]

Objectives: To examine: i) the mean changes in adolescent females' body mass index (BMI), global self-esteem, physical self-perceptions, social physique anxiety, physical activity, and dietary restraint; ii) the stability of measuring self-perceptions, BMI, self-esteem, physique anxiety, activity, and dietary restraint; and iii) the relationships among changes in these variables over 12 months.Methods: 631 female adolescents (15-16 years old) involved in a two-year study of self-report measures completed validated questionnaires in high school classroom settings.Results: There were small but significant group increases in BMI and social physique anxiety and significant decreases in sport, conditioning, and strength physical self-perceptions and physical activity. Stability analysis indicates moderate to strong stability for all variables. Change analyses indicated that BMI, due to its high stability, is a poor predictor of change in all variables. Stronger significant correlations were noted between change in body appearance self-perceptions and change in social physique anxiety (r=-0.54) and dietary restraint (r=-0.27). There was also a significant relationship between change in physical activity and the physical self-perceptions, although conditioning was the only significant (p<0.05) predictor of change in physical activity (beta=0.340).Interpretation: Physical self-perceptions are a stronger predictor of change in physical activity, dietary restraint, and social physique anxiety compared to BMI. This demonstrates the importance of physical self-perceptions when investigating health-related behaviours associated with dieting and physical activity. The decline in physical activity and increase in BMI is an ongoing concern, as is the link between body appearance self-perceptions and dietary restraint and social physique anxiety. [ABSTRACT FROM AUTHOR]

This paper reports electrical properties of CoO thin films of different thickness in the range 0.375 – 7.95 µm. Both electrical conductivity and thermopower were measured at elevated temperatures (1223 – 1423 K) and under controlled oxygen partial pressure (5 − 2.1x104 Pa). It was found that at low p(O2) the electrical conductivity decreases with film thickness. The activation energy of the electrical conductivity (Ea) in air decreases with the oxide thickness from 0.56 eV at 0.375 µm to 0.52 eV for massive CoO while at low p(O2)=5 Pa the Ea is independent of the thickness (Ea = 0.46 eV). The reciprocal of the p(O2) exponent of the electrical conductivity (nδ) in the range 1223 K – 1373 K is close to four for the 7,95 µm film and is about 3.5–3.7 for the 0.375 µm film. The electrical properties of the CoO thin films are considered assuming different defect structures in the bulk phase and the surface layer. [ABSTRACT FROM AUTHOR]

This paper reports the results of the electrical conductivity measurements for polycrystalline specimens of undoped and Cr-doped CoO in the ranges of p(O2) (10−5 – 105 Pa) and temperature (1223 – 1373 K). The experimental data are considered in terms of the effect of Cr on semiconducting properties of CoO. It is shown that Cr results in a decrease of the reciprocal of the p(O2) exponent of electrical conductivity, however, the obtained experimental values are substantially lower than those predicted by defect chemistry. The activation energy of the electrical conductivity remains independent of p(O2) and Cr content (at the level of about 0.5 eV) except strongly reduced CoO, at p(O2)=2.10−4 Pa, of which the activation energy is substantially higher. Thermopower vs p(O2) exhibits maximum at p(O2)=10 Pa (except of thermopower data for Cr-doped CoO at the highest temperature). The experimental data are considered in terms of the effect of both p(O2) and Cr on semiconducting properties. [ABSTRACT FROM AUTHOR]

We have studied surface-directed phase separation in thin films of deuterated polystyrene and poly(bromostyrene) (with 22.7% of monomers brominated) using 3He nuclear reaction analysis, dynamic secondary ion mass spectroscopy and atomic force microscopy combined with preferential dissolution. The crossover from competing to neutral surfaces of the critical blend film (cast onto Au) was commenced: polyisoprene-polystyrene diblock copolymers were added and segregated to both surfaces reducing in a tuneable manner the effective interactions. Two main stages of phase evolution are characterised by i) the growth of two surface layers and by ii) the transition from the four-layer to the final bilayer morphology. For increasing copolymer content the kinetics of the first stage is hardly affected but the amplitude of composition oscillations is reduced indicating more fragmented inner layers. As a result, a faster mass flow to the surfaces and an earlier completion of the second stage were observed. The hydrodynamic flow mechanism, driving both stages, is evidenced by nearly linear growth of the surface layer and by mass flow channels extending from the surface layer into the bulk. The final bilayer structure, formed even for the surfaces covered by strongly overlapped copolymers, is indicative of long-range (antisymmetric) surface forces. [ABSTRACT FROM AUTHOR]

The Ni22Cr10Al1Y alloy was exposed in H2/H2S gas mixture under the sulphur pressure 10−3 and 1 Pa as well as in SO2 at 1173 and 1273 K. At ps = 1 Pa the sulphidation rate was relatively high and the reaction obeyed the linear rate law. Under these conditions a nickel/nickel sulphide eutectic was formed. At ps = 10−3 Pa nickel sulphides became unstable and the sulphidation rate was significantly lower. The reaction obeyed the parabolic rate law. The oxidation rate of the alloy in SO2 was lower than that in any of the H2/H2S atmospheres. The sulphide scales formed during sulphidation in H2/H2S had complex microstructures and compositions, with sulphospinel and sulphide phases being present, e.g. NiCr2S4, Ni3S2, CrxSy. As the temperature increased and the sulphur pressure decreased, these phases were replaced by the chromium-rich sulphide phase. Various oxides formed during oxidation of the alloy in SO2. [ABSTRACT FROM AUTHOR]

Zinc fingers (ZnFs) are generally regarded as DNA-binding motifs. However, a number of recent reports have implicated particular ZnFs in the mediation of protein-protein interactions. The N-terminal ZnF of GATA-1 (NF) is one such finger, having been shown to interact with a number of other proteins, including the recently discovered transcriptional co-factor FOG. Here we solve the three-dimensional structure of the NF in solution using multidimensional 1H/15N NMR spectroscopy, and we use 1H/15N spin relaxation measurements to investigate its backbone dynamics. The structure consists of two distorted β-hairpins and a single α-helix, and is similar to that of the C-terminal ZnF of chicken GATA-1. Comparisons of the NF structure with those of other C4-type zinc binding motifs, including hormone receptor and LIM domains, also reveal substantial structural homology. Finally, we use the structure to map the spatial locations of NF residues shown by mutagenesis to be essential for FOG binding, and demonstrate that these residues all lie on a single face of the NF. Notably, this face is well removed from the putative DNA- binding face of the NF, an observation which is suggestive of simultaneous roles for the NF; that is, stabilisation of GATA-1 DNA complexes and recruitment of FOG to GATA-1-controlled promoter regions. [ABSTRACT FROM AUTHOR]

A small experiment, «MiniMax», has been set up in the C0 intersection region of the Fermilab Tevatron to seek evidence for disoriented chiral condensates and to study other forward physics phenomena. The experiment consists of a proportional wire chamber telescope accompanied by scintillation (trigger) counters, a lead converter, and followed by an electromagnetic calorimeter. The solid angle accepted is a cone centered at pseudorapidity (η) of 4.1 and of radius (in η-ϕ space) of about 0.6. Over 2.5 million events thus far have demonstrated the successful operation of the apparatus, however to date the analysis has not progressed sufficiently to permit any conclusions concerning disoriented chiral condensates. [ABSTRACT FROM AUTHOR]

The impact of climatic change on variables of concern to eco-hydrology was examined. Long time series of records of temperature, precipitation and river flow for Poznan were analyzed and forecasts of tendencies were made. Spatial distribution of runoff and of the ratio of evapotranspiration to precipitation was obtained for the country. It was found likely that the dynamics of the hydrological cycle will accelerate. Annual precipitation, runoff and evapotranspiration will increase. The joint effect, including estimated growth in water demand, is likely to be a decrease in the amount of soil moisture. [ABSTRACT FROM AUTHOR]

Copyright of Il Nuovo Cimento: A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento della Societa Italiana di Fisica: B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The gauge-fixing terms of the free, real-time thermal gauge field propagators corresponding to quantization in a covariant gauge obtained by Kobes, Semenoff, and Weiss are shown to be incorrect, apart from well-known signature ambiguities in the off-diagonal elements, and to differ from those obtained by Landsman using the method of the Klein-Gordon divisor. We obtain the correct forms which are then shown to coincide with Landsman's results by means of a distributional identity. [ABSTRACT FROM AUTHOR]

The power of chemistry to prepare new molecules and materials has driven the quest for new approaches to solve problems having global societal impact, such as in renewable energy, healthcare and information science. In the latter case, the intrinsic quantum nature of the electronic, nuclear and spin degrees of freedom in molecules offers intriguing new possibilities to advance the emerging field of quantum information science. In this Perspective, which resulted from discussions by the co-authors at a US Department of Energy workshop held in November 2018, we discuss how chemical systems and reactions can impact quantum computing, communication and sensing. Hierarchical molecular design and synthesis, from small molecules to supramolecular assemblies, combined with new spectroscopic probes of quantum coherence and theoretical modelling of complex systems, offer a broad range of possibilities to realize practical quantum information science applications., (© 2020. Springer Nature Limited.)

Objective: To investigate the relationship among BMI, smoking consumption, dietary restraint, smoking to control weight, physical self-perception and self-esteem in young female adolescents., Methods: 702 grade 9 students (14-15 yrs old) completed self-reported validated measures in classroom settings., Results: 26.7% of students had smoked in the last 30 days. Cigarette consumption was low with only 13% smoking one or more cigarettes a day. MANOVA revealed smokers had higher dietary restraint and lower perceptions of physical appearance, conditioning, and self-esteem. A similar pattern emerged for those girls classified as using smoking to control weight. Multiple regression found dietary restraint was predicted by higher BMI, and lower body appearance and self-esteem., Conclusions: The data provided converging evidence that girls with low self-perceptions are more likely to engage in health-compromising behaviours. Smoking behaviours and dietary restraint were also linked. However, the small effect sizes for smoking behaviours warrants caution.