From plants to nematodes: Serratia grimesii BXF1 genome reveals an adaptation to the modulation of multi-species interactions

Serratia grimesii BXF1 is a bacterium with the ability to modulate the development of several eukaryotic hosts. Strain BXF1 was isolated from the pinewood nematode, Bursaphelenchus xylophilus, the causative agent of pine wilt disease affecting pine forests worldwide. This bacterium potentiates Bursaphelenchus xylophilus reproduction, acts as a beneficial pine endophyte, and possesses fungal and bacterial antagonistic activities, further indicating a complex role in a wide range of trophic relationships. In this work, we describe and analyse the genome sequence of strain BXF1, and discuss several important aspects of its ecological role. Genome analysis indicates the presence of several genes related to the observed production of antagonistic traits, plant growth regulation and the modulation of nematode development. Moreover, most of the BXF1 genes are involved in environmental and genetic information processing, which is consistent with its ability to sense and colonize several niches. The results obtained in this study provide the basis to a better understanding of the role and evolution of strain BXF1 as a mediator of interactions between organisms involved in a complex disease system. These results may also bring new insights into general Serratia and Enterobacteriaceae evolution towards multitrophic interactions

Effect of the particle size range of construction and demolition waste on the fresh and hardened-state properties of fly ash-based geopolymer mortars with total replacement of sand

This study seeks the valorization of industrial residues (fly ash and construction and demolition waste (CDW)) through the production of geopolymer mortars. The effect of the sand substitution by CDW and the influence of the particle size range of CDW fine aggregates on the fresh and hardened properties of the mortars were evaluated. Geopolymer mortars were produced using biomass fly ash waste and metakaolin as a binder, CDW as fine aggregates, and an alkali solution of sodium silicate and sodium hydroxide as activator. The geopolymer mortars were characterized in fresh state by the flow table test and in the hardened state through chemical, physical/microstructural analyzes. The mortars produced with CDW showed lower flowability when compared to the ones prepared with sand. The compressive and flexural strength of hardened mortars, respectively, obtained with residues were higher when compared to sand: 40 MPa and 8.5 MPa with CDW, against 23 MPa and 3.1 MPa for sand-based samples. It was observed that mortars developed with recycled aggregate and natural aggregate present similar chemical and mineralogical compositions. The superior results obtained in the mechanical properties of mortars produced with CDW are related to the recycled aggregate-geopolymer paste interface.publishe

Spectrum of confining strings in SU(N) gauge theories

We study the spectrum of the confining strings in four-dimensional SU(N) gauge theories. We compute, for the SU(4) and SU(6) gauge theories formulated on a lattice, the string tensions sigma_k related to sources with Z_N charge k, using Monte Carlo simulations. Our results are consistent with the sine formula sigma_k/sigma = sin k pi/N / sin pi/N for the ratio between sigma_k and the standard string tension sigma. For the SU(4) and SU(6) cases the accuracy is approximately 1% and 2%, respectively. The sine formula is known to emerge in various realizations of supersymmetric SU(N) gauge theories. On the other hand, our results show deviations from Casimir scaling. We also discuss an analogous behavior exhibited by two-dimensional SU(N) x SU(N) chiral models.Comment: Latex, 34 pages, 10 figures. Results of new SU(4) simulations added. The new data are included in the analysis, leading to improved final estimates for SU(4). Conclusions unchange

Laser Surface Modification in Ti-xNb-yMo Alloys Prepared by Powder Metallurgy

[Abstract] The main objective was to study the effect of surface modification by laser on Ti-Nb-Mo powder metallurgical alloys to improve their mechano-chemical behavior and their application as a biomedical implant. The used powder mixtures were produced in an inert atmosphere. Uniaxial compaction took place at 600 MPa with high-vacuum sintering at 1250 °C for 3 h. The specimens for the three-point flexure test were prepared and their mechanical properties determined. Microstructural characterization was performed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) to obtain the distribution of phases, porosity, size, and shape of the grains of each alloy. Corrosion behavior was evaluated by electrochemical tests using an artificial saliva electrolyte modified from Fusayama at 37 °C. Chemical characterization was completed by analyzing the ionic release by Inductively coupled plasma atomic emission spectroscopy (ICP-EOS) after immersion for 730 h in Fusayama solution modified with NaF at 37 °C to simulate a 20-year life span based on a daily 2-min cycle of three toothbrushes. Corrosion behavior confirmed promising possibilities for the biomedicine field. The surface porosity of the samples not submitted to surface treatment deteriorated properties against corrosion and ion release. The obtained phase was β, with a low α”-martensite percentage. The maximum resistance to bending was greater after surface fusion. Plastic deformations were above 7% under some conditions. Microhardness came close to 300 HV in heat-affected zone (HAZ) and 350 HV in fusion zone (FZ) (under the determined condition. The elastic modulus lowered by around 10%. The corrosion rate was lower in Ti-27Nb-8Mo and Ti-35Nb-6Mo. Niobium release was significant, but below the physiological limit.The authors thank the Ministerio de Economía y Competitividad de España for Research Project RTI2018-097810-B-I00 and the Ministerio de Economía y Competitividad de España for Research Project RTI2018-096472-B-I00. The European Commission thanks to FEDER and the São Paulo State Research Support Foundation (FAPESP) [Grant: 2019/24237-6].Fundação de Amparo à Pesquisa do Estado de São Paulo; 2019/24237-

Extraction of cocoa butter by supercritical carbon dioxide: optimization of operating conditions and effect of particle size.

The optimum operating conditions for the extraction of cocoa butter from cocoa liquor using supercritical carbon dioxide and the effect of sample particle size on cocoa butter extraction under optimized operating conditions were investigated. The optimization was conducted at 10–45 MPa and 35–75C, with extraction times of 1–12 h by response surface methodology. The effect of particle size was studied using cocoa liquor, ground cocoa nibs and crushed cocoa nibs with particle sizes of approximately 74 µm, 0.85–1 mm and 4–6 mm, respectively. The yield was analyzed for total fat content by gravimetric method and triacylglycerol (TAG) profile by high-performance liquid chromatography. The results showed higher yield of cocoa butter with higher values of pressure, temperature and extraction time. The optimum conditions for cocoa butter extraction were 45 MPa, 75C and 12 h. The smaller particle size produced a higher yield of cocoa butter. 1,3-Dipalmitoyl-2-oleoyl-glycerol (POP), 1-palmitoyl-2-oleoyl-3-stearoyl-glycerol (POS) and 1,3-distearoyl-2-oleoyl-glycerol (SOS) were the major TAGs present in the extracted cocoa butter, with POS being the highest (>30%) for all treatments studied

Jet color chemistry and anomalous baryon production in AAAA-collisions

We study anomalous high-$p_T$ baryon production in $AA$-collisions due to formation of the two parton collinear $gq$ system in the anti-sextet color state for quark jets and $gg$ system in the decuplet/anti-decuplet color states for gluon jets. Fragmentation of these states, which are absent for $NN$-collisions, after escaping from the quark-gluon plasma leads to baryon production. Our qualitative estimates show that this mechanism can be potentially important at RHIC and LHC energies.Comment: 20 pages, 4 figures, Eur.Phys.J. versio

High-precision determination of the critical exponents for the lambda-transition of 4He by improved high-temperature expansion

We determine the critical exponents for the XY universality class in three dimensions, which is expected to describe the $\lambda$-transition in ${}^4$He. They are obtained from the analysis of high-temperature series computed for a two-component $\lambda\phi^4$ model. The parameter $\lambda$ is fixed such that the leading corrections to scaling vanish. We obtain $\nu = 0.67166(55)$, $\gamma = 1.3179(11)$, $\alpha=-0.0150(17)$. These estimates improve previous theoretical determinations and agree with the more precise experimental results for liquid Helium.Comment: 8 pages, revte

Calorimetric and transport investigations of CePd_{2+x}Ge_{2-x} (x=0 and 0.02) up to 22 GPa

The influence of pressure on the magnetically ordered CePd_{2.02}Ge_{1.98} has been investigated by a combined measurement of electrical resistivity, $\rho(T)$, and ac-calorimetry, C(T), for temperatures in the range 0.3 K<T<10 K and pressures, p, up to 22 GPa. Simultaneously CePd_2Ge_2 has been examined by $\rho(T)$ down to 40 mK. In CePd_{2.02}Ge_{1.98} and CePd_2Ge_2 the magnetic order is suppressed at a critical pressure p_c=11.0 GPa and p_c=13.8 GPa, respectively. In the case of CePd_{2.02}Ge_{1.98} not only the temperature coefficient of $\rho(T)$, A, indicates the loss of magnetic order but also the ac-signal $1/V_{ac}\propto C/T$ recorded at low temperature. The residual resistivity is extremely pressure sensitive and passes through a maximum and then a minimum in the vicinity of p_c. The (T,p) phase diagram and the A(p)-dependence of both compounds can be qualitatively understood in terms of a pressure-tuned competition between magnetic order and the Kondo effect according to the Doniach picture. The temperature-volume (T,V) phase diagram of CePd_2Ge_2 combined with that of CePd_2Si_2 shows that in stoichiometric compounds mainly the change of interatomic distances influences the exchange interaction. It will be argued that in contrast to this the much lower p_c-value of CePd_{2.02}Ge_{1.98} is caused by an enhanced hybridization between 4f and conduction electrons.Comment: 9 pages, 7 figure

Novel universality class of absorbing transitions with continuously varying critical exponents

The well-established universality classes of absorbing critical phenomena are directed percolation (DP) and directed Ising (DI) classes. Recently, the pair contact process with diffusion (PCPD) has been investigated extensively and claimed to exhibit a new type of critical phenomena distinct from both DP and DI classes. Noticing that the PCPD possesses a long-term memory effect, we introduce a generalized version of the PCPD (GPCPD) with a parameter controlling the memory effect. The GPCPD connects the DP fixed point to the PCPD point continuously. Monte Carlo simulations show that the GPCPD displays novel type critical phenomena which are characterized by continuously varying critical exponents. The same critical behaviors are also observed in models where two species of particles are coupled cyclically. We suggest that the long-term memory may serve as a marginal perturbation to the ordinary DP fixed point.Comment: 13 pages + 10 figures (Full paper version