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We report the magnitude of the induced magnetic moment in CVD-grown epitaxial and rotated-domain graphene in proximity with a ferromagnetic Ni film, using polarized neutron reflectivity (PNR) and X-ray magnetic circular dichroism (XMCD). The XMCD spectra at the C K-edge confirms the presence of a magnetic signal in the graphene layer and the sum rules give a magnetic moment of up to $\sim\,0.47\,\mu$_B/C atom induced in the graphene layer. For a more precise estimation, we conducted PNR measurements. The PNR results indicate an induced magnetic moment of $\sim$ 0.53 $\mu$_B/C atom at 10 K for rotated graphene and $\sim$ 0.38 $\mu$_B/C atom at 10 K for epitaxial graphene. Additional PNR measurements on graphene grown on a non-magnetic Ni_9Mo_1 substrate, where no magnetic moment in graphene is measured, suggest that the origin of the induced magnetic moment is due to the opening of the graphene's Dirac cone as a result of the strong C pz-3d hybridization., Comment: 21 pages, 7 figures

Accurate detection and quantification of regional vegetation trends is essential for understanding the dynamics of landscape ecology and vegetation distribution. We applied a comprehensive trend analysis to satellite data to describe geo-spatial changes in vegetation along the Pacific slope of Peru and northern Chile, from sea level to the continental divide, a region characterised by biologically unique and highly sensitive arid and semi-arid environments. Our statistical analyses show broad regional patterns of positive trends in EVI, called “greening” alongside patterns of “browning” where trends are negative between 2000 and 2020. The coastal plain and foothills, up 1000m, contain notable greening of the coastal Lomas and newly irrigated agricultural lands occurring alongside browning trends related to changes in land use practices and urban development. Strikingly, the precordilleras show a distinct ’greening strip’ which extends from approximately 6°S to 22°S, with an altitudinal trend; ascending from the tropical lowlands (170-780 m) in northern Peru, to the subtropics (1000-2800 m) in central Peru, and temperate zone (2600-4300 m) in southern Peru and northern Chile. We find that the geographical characteristics of the greening strip do not match climate zones previously established by Köppen and Geiger. Greening and browning trends in the coastal deserts and the high Andes lie within well defined climatic and life zones, producing variable but identifiable trends. However, the distinct Pacific slope greening presents an unexpected distribution with respect to the regional Köppen-Geiger climate and life zones. This work provides insights on understanding the effects of climate change on Peru’s diverse ecosystems in highly sensitive, biologically rich arid and semi-arid environments on the Pacific slope.

Contains fulltext : 251996.pdf (Publisher’s version ) (Open Access) We report an autosomal recessive, multi-organ tumor predisposition syndrome, caused by bi-allelic loss-of-function germline variants in the base excision repair (BER) gene MBD4. We identified five individuals with bi-allelic MBD4 variants within four families and these individuals had a personal and/or family history of adenomatous colorectal polyposis, acute myeloid leukemia, and uveal melanoma. MBD4 encodes a glycosylase involved in repair of G:T mismatches resulting from deamination of 5'-methylcytosine. The colorectal adenomas from MBD4-deficient individuals showed a mutator phenotype attributable to mutational signature SBS1, consistent with the function of MBD4. MBD4-deficient polyps harbored somatic mutations in similar driver genes to sporadic colorectal tumors, although AMER1 mutations were more common and KRAS mutations less frequent. Our findings expand the role of BER deficiencies in tumor predisposition. Inclusion of MBD4 in genetic testing for polyposis and multi-tumor phenotypes is warranted to improve disease management.

Appendix S1. British Columbia Cancer Agency epidemiological questionnaire administered to lung cancer study participants Appendix S2. Logistic regression Model 2 (article Table 2) expressed with beta coefficients and model constant (Stata statistical program printout) Appendix S3. Logistic regression Model 3 (article Table 2) expressed with beta coefficients and model constant (Stata statistical program printout) Appendix S4. Logistic regression model including Table 2 base Model 1 plus sputum DNA image cytometry, expressed with beta coefficients and model constant (Stata statistical program printout) Appendix S5. Cox proportional hazards model analogous to the logistic regression Model 3 (article Table 3)

Perspective on this Article from Ovarian Adenocarcinomas in the Laying Hen and Women Share Similar Alterations in p53, ras, and HER-2/neu

We report the preparation and characterization of YBa2Cu3O7 (YBCO) films grown onto SrTiO3 and YSZ substrates by the trifluoroacetates chemical solution deposition method and following sintering with oxygen atmosphere at 860 °C. The X-ray diffraction (XRD) reveals (00ℓ) – oriented crystallites indicating epitaxial growth of the films in the c-direction. Despite granular morphology and the presence of Y2BaCuO5 and CuO as minor secondary phases, the technique shows the successful formation of the superconducting YBCO and preventing the formation of the unwanted BaCO3 phase. Rocking curve measurements of the (005) reflection for the YBCO/SrTiO3 was fitted with one Gaussian function with full width at the half maximum (FWHM) of 0.44° confirming that it consists of YBCO crystallites with different texture. For the sample grown on YSZ, the rocking curve was fitted with two Gaussian functions, one corresponding to the YBCO layer (FWHM = 0.4°) and another to the substrate (FWHM = 0.3°). The magnetic measurements taken in zero field cooling and field cooling modes confirm the formation of the superconducting YBCO with critical temperatures (TC) 91.8 and 85.7 K for the samples grown onto YSZ and SrTiO3, respectively. The critical current density (JC) curves indirectly calculated by using the Bean´s model from the M(T) loops were JC ~ 109 A/cm2 for the sample deposited onto YSZ and JC ~ 107A/cm2 for the YBCO deposited onto SrTiO3. Overall, the difference in TC and JC values between both samples could be related to their difference in oxygen content, porosity, hole concentration per Cu ion and the presence of secondary phases.

The objective of this study was to determine the impact on termite feeding of wood ring count and MC in standard tests. Introduced species ( Coptotermes formosanus ) were tested in an American Wood Protection Association (AWPA) E1-97 standard laboratory test. Samples with a ring count in the range of 6 – 10 rings per inch (RPI) had a higher, but not significantly different, weight loss than the 4 – 6 RPI specified by E1-97. With respect to the MC, it was determined that a lower level of moisture than that currently specified by AWPA E1 would be preferred over the higher MC achieved in ASTM D3345. Sample placement on top of the sand was recommended over the burial procedure in ASTM D3345.

Expanding nanomagnetism and spintronics into three dimensions (3D) offers great opportunities for both fundamental and technological studies. However, probing the influence of complex 3D geometries on magnetoelectrical phenomena poses important experimental and theoretical challenges. In this work, we investigate the magnetoelectrical signals of a ferromagnetic 3D nanodevice integrated into a microelectronic circuit using direct-write nanofabrication. Due to the 3D vectorial nature of both electrical current and magnetization, a complex superposition of several magnetoelectrical effects takes place. By performing electrical measurements under the application of 3D magnetic fields, in combination with macrospin simulations and finite element modelling, we disentangle the superimposed effects, finding how a 3D geometry leads to unusual angular dependences of well-known magnetotransport effects such as the anomalous Hall effect. Crucially, our analysis also reveals a strong role of the non-collinear demagnetizing fields intrinsic to 3D nanostructures, which results in an angular dependent magnon magnetoresistance contributing strongly to the total magnetoelectrical signal. These findings are key to the understanding of 3D spintronic systems and underpin further fundamental and device-based studies., Leverhulme Trust Isaac Newton Trust L’Oréal-UNESCO U.K. and Ireland Fellowship For Women In Science EPSRC Winton Program for Physics of Sustainability China Scholarship Council European Union’s Horizon 2020 research and innovation program Spanish AEI

The objective of this study was to determine the impact on termite feeding of wood sample size and species and test photoperiod in standard tests. Native species (Reticulitermes flavipes) and introduced species (Coptotermes formosanus) were tested in an American Wood-Preservers' Association E1 standard laboratory test. For testing involving treated wood, southern yellow pine was determined to be preferable to spruce based on its treatability and availability. Test blocks of 25 by 25 by 6 mm were deemed adequate for testing, with large blocks presenting difficulty with retrieval of termites to determine mortality and smaller blocks being consumed too rapidly by the termites in the test. Photoperiod comparisons were not significantly different for R. flavipes; however, C. formosanus indicated a preference for 100 percent darkness. Therefore, the recommendation is to maintain tests using each species in a 100 percent dark environment.

The squaryl moiety has emerged as an important phosphate bioisostere with reportedly greater cell permeability. It has been used in the synthesis of several therapeutic drug molecules including nucleoside and nucleotide analogues but is yet to be evaluated in the context of positron emission tomography (PET) imaging. We have designed, synthesised and evaluated 3′-[18F]fluorothymidine-5′-squaryl ([18F]SqFLT) as a bioisostere to 3′-[18F]fluorothymidine-5′-monophosphate ([18F]FLTMP) for imaging thymidylate kinase (TMPK) activity. The overall radiochemical yield (RCY) was 6.7 ± 2.5% and radiochemical purity (RCP) was >90%. Biological evaluation in vitro showed low tracer uptake (

This article explores the benefits covering waterborne preservative systems that include an oil emulsion treatment. Waterborne preservatives have a long history of protecting wood products in severe exposures. Enhancing the surface of these products can increase their service life. Oil emulsion treatments were originally developed to improve the climbability of waterborne poles by utility linemen. Over time, these products have shown that they can improve other surface characteristics, such as checking, flammability, and, with added pigments, ultraviolet exposure.

The objective of this study was to determine if the same soldier:worker ratio could be used in the eastern subterranean termite (Reticulitermes flavipes) and the Formosan subterranean termite (Coptotermes formosanus) in standard tests. Native (R. flavipes) and introduced (C. formosanus) subterranean termite species were tested in an American Wood Protection Association E1 standard laboratory test. Statistically equivalent weight losses were found as long as the ratio was within 10 percent of the rate required by the standard.

Seventy-five years of research in wood protection at the Forest Products Lab at Mississippi State University are described. A history of wood protection is presented along with an overview of the facilities supporting the research. Program objectives are presented along with the personnel responsible for building the program. A brief presentation of research areas is given followed by some program metrics.

Fungal decay and fire resistance properties of wood treated with nano-chitosan-TPP particles were investigated. Quaternized and non-quaternized nano-chitosan particles crosslinked with a commercial fire-retardant, tripolyphosphate, were prepared from low molecular weight chitosan (with a molecular weight of 50 to 190 kDa). Different treatments were performed on southern yellow pine wood samples via a vacuum impregnation process for both quaternized and non-quaternized nano-chitosan-TPP particles with a concentration ratio of 12% to 4.8% (nano-chitosan to TPP). Both the leached and unleached treated wood samples were exposed to brown rot (Gloeophyllum trabeum) and white rot (Trametes versicolor) fungi according to AWPA standard E10-16. The flammability test was performed with a cone calorimeter according to ASTM standard E1354-15. The heat release rate and the mass loss rate were measured. The results of the fungal tests indicated that the quaternization of the nano-chitosan particles resulted in a reduced mass loss in the pine samples when exposed to Trametes versicolor under leached conditions. Additionally, without the quaternization of the nano-chitosan particles, the mass loss in the pine samples was reduced when exposed to Gloeophyllum trabeum under unleached conditions. The production of nano-chitosan-TPP particles had a significant effect on the fire-retardant activity of the treated wood samples.

The efficacy of chitosan oligomers and related nanoparticles as environmentally friendly wood protection agents was evaluated in this study. Commercially sourced low-molecular weight chitosan was depolymerized using sodium nitrite. Evaluation of depolymerized chitosan to the nano level by thin layer chromatography confirmed acceptable results for obtaining a degree of polymerization of four. Then, oligomers were modified to form quaternized chitosan oligomers. Both quaternized and non-quaternized oligomers were mixed with tripolyphosphate (TPP) to form nano-chitosan-TPP particles via an ionic gelation method. Southern pine wood samples were treated with different chitosan-based solutions and suspensions under a vacuum impregnation process. The mass and volume of the treated samples were calculated before and after treatments to evaluate bulking. The mass loss after leaching of the treated wood samples was calculated. The mass and volume gain results indicated that quaternized nano-chitosan-TPP treated samples had more mass and volume gain after treatment in comparison with non-quaternized nano-chitosan-TPP-treated and control samples. The mass loss results revealed that mass loss increased in quaternized nano-chitosan-TPP particles. Although quaternized nano-chitosan particles were positively charged, they could not fix to the cell walls and became leached out. Therefore, these nanoparticles can likely be used as wood preservatives in non-leaching applications.

Southern pine lumber 2 by 8s and 2 by 10s from across the Southeast were used as the parent material source for this study. Fundamental data were collected for each piece of lumber: growth rings per inch (RPI), presence of pith, and specific gravity (SG), among other information. After mechanical property evaluation through static bending, small clear specimens were cut from the lumber pieces and tested for compression perpendicular to grain (C⊥). Those values were then compared with 2 by 8 and 2 by 10 average RPI and density. The results were significant for both tests. Therefore, a segmentation of the growth ring data into groups of 5 RPI was conducted. Correlations were run specific to each group, per both lumber sizes, and still significance was found. Segmentation of SG was not significant only for 2 by 8 SG

The objective of this study was to evaluate the relationship of growth characteristics to compression properties from commercially available southern pine lumber. The in-grade No. 2 southern pine lumber was collected from retail stores across the Southeast United States. For this specific project, 797 samples of 2 × 8 and 2 × 10 boards were examined. The samples were subjected to static bending following ASTM D 198 to determine mechanical properties. The 2 × 8 samples averaged 4.78 growth rings per inch (RPI) and the 2 × 10s averaged 3.95. Average density (ρ) was 477 kg·m-3 in the 2 × 8 and 487 kg·m-3 for the 2 × 10 specimens. From small clear samples from the parent boards, compression parallel to grain averaged from 43.78 MPa for the 2 × 8 to 46.77 MPa for the 2 × 10. Correlations were run to test significance among growth rings per inch and compressions parallel to grain, across both sizes: 2 × 8 and 2 × 10. Slight significance was found in those correlations and increased in measure from 2 × 8 to 2 × 10. The segmentation of RPI into three distinct groups helped strengthen the findings of effect on compression parallel to grain. Moreover, the addition of density as another test variable further strengthened in relationship per those RPI categorizations. Statistically significant findings for density per RPI segments, R2 values: for 2 × 8 equal 0.31 (3 or less RPI) to 0.60 (more than 5 RPI). For the 2 × 10 lumber per the same segments, R2 values: 0.39, 0.46 and 0.25, respectively. The results suggest ρ is a better predictor than RPI alone for compression parallel to grain values.

Carbonatite is an igneous rock that is composed mainly of carbonate minerals and silicates. It is recently applied as fertilizer due to its high content of calcite and dolomite. This study presents a physical and chemical characterization of the Spanish River Carbonatite (SRC) and its application as fertilizer is tested. The chemical composition obtained by X-ray fluorescence and Energy Dispersive X-ray analyses indicates that Ca, Fe and Si are the main contained elements. Calcite and SiO2 are the principal mineralogical phases as detected by X-ray diffraction. Fourier transform infrared spectroscopy confirms the presence of calcite, silicates and also organic material and water. It also suggests the presence of vermiculite. Thermal analysis reveals only a one-step reaction that corresponds to the decomposition of calcite. Mössbauer spectroscopy performed at room temperature do not show magnetic order between the iron moments instead it shows Fe2+ and Fe3+ doublets in M1 and M2 octahedral sites belonging to vermiculite. At 50 K, we observe that the isomer shift increases their values due to the second order Doppler shift. SQUID magnetometry measurements reveal that most of the sample contains paramagnetic domains assigned to the silicates and calcite components. However, under low applied fields, a tiny signal for Verwey transition appears at 124 K (suggesting the presence of magnetite) although screened by the strong paramagnetic signal of the main components. The SRC has been tested as potential fertilizer on sweet cucumber (Solanum muricatum) which responded positively to the application to carbonatite as an amendment, expressing itself in high foliar biomass.

The steel industry produces large amounts of slag coming from different stages during the steelmaking process every year. Currently, there are numerous attempts to recycle it or to use it in some other industry sectors and to preserve the environment. The characteristics of the slag depends on the steelmaking process and it is crucial to have it before any attempt of recycling. In this work, slag sample produced in the ladle furnace from SIDERPERU steel plant were collected and analyzed by using energy dispersion X-ray (EDX), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), SQUID magnetometer and Mössbauer spectroscopy. The chemical analysis obtained by EDX and XRF indicate that the main elemental composition of the material is Fe, Ca, Si and Cr. XRD identifies that these elements are in the phases: FeO, Fe3O4, α-Fe2O3, Ca2SiO4, and Ca2,32Mn0,68SiO7. Magnetometry measurements suggest the Verwey transition for magnetite and the Morin transition for hematite are screened by the presence of superparamagnetic phases. The Mössbauer spectrum shows two doublets related to Fe2+ and Fe3+ ions with hyperfine parameters belonging to that of non-stoichiometric wustite. Also, the presence of hyperfine fields characteristic of the Fe3O4 and Fe2O3 phase identified at room temperature verifies the magnetometry analysis. The analysis of the sample used in this work reveals details connected with the steel fabrication processes and are helpful for posterior recycling attempts.

The primary process in an electrical arc furnace (EAF) during industrial steelmaking results in tons of black slags which cause pollution to the environment. In this work, the iron oxides of black slags generated in the EAF from the SIDERPERU plant, Peru was reduced via the carbothermal reaction. The reduction of the black slag to α-Fe is demonstrated by X-ray diffraction, Mӧssbauer spectroscopy and magnetometry. However, phases with calcium and silicon persist in the sample after the carbothermal process. The thermodynamic calculations of the most probable reactions sequence were performed to understand the reduction process. The magnetometry measurements confirm the presence of ferromagnetic domains, supporting the success of the reduction of the black slag to α-Fe. The reduced black slags were recycled into a HRB335 steel rod by consolidation and extrusion processes and inspected by X-ray fluorescence.

The biological and medical aspects of magnetochemical effects in nanotherapy of tumors remain poorly studied. The present paper investigates the influence of nonlinear magnetochemical effects of anisotropic magnetic nanodots on an animal tumor model. The magnetic properties and electron spin resonance spectra of magnetic nanodots and doxorubicin were investigated after mechano-magnetochemical synthesis. The results obtained from the analysis of nonlinear kinetics and survival in Walker-256 carcinosarcoma-bearing animals found a nonlinear dependence between the value of the growth factor, braking ratio, survival rate, tumor redox state, and the treatment by the magnetic nanodot combined with a nonuniform constant magnetic field. To quantify the heterogeneity in microphotographs of Walker-256 carcinosarcoma sections, we applied the entropy parameter. The control (no treatment) group showed the greatest heterogeneity. The lowest value of tumor heterogeneity among animals given treatment was found in groups with the minimum growth factor. Similarly, the lowest entropy value was found in muscle tissue taken from inoculation areas of the tumor. The evidence from this study concluded that inhomogeneous constant magnetic fields with different strength applied to heterogeneous tumor tissues induced different magnetic anisotropy in the magnetic nanodot which had a significant influence on the nonlinear kinetics, redox state, and histological pattern of the tumor.

We present the magnetic, structural and 57Fe Mossbauer characterization of soils collected from an ancient mercury contaminated city named Huancavelica in Peru. The characterization results indicate that silicates and carbonates are the main mineralogical constituents in the samples. In addition, 57Fe Mössbauer spectra at room temperature reveal, the presence of two components: a magnetic component related to magnetic Fe-oxides (magnetite, hematite, goethite) and a high non-magnetic component related to Fe+3 in high spin configuration and tetrahedral coordination in silicates. The magnetization measurements present screening of paramagnetic, ferromagnetic and antiferromagnetic signals, typical from soils containing different silicates and iron minerals. Remarkably the Verwey and Morin transitions corresponding to magnetite and hematite, respectively, are screened by the paramagnetic signal corresponding to the major silicate components in the samples. Overall, the soils are mainly composed of crystalline and amorphous silicates, calcites and iron bearing which are typical from Andean soils.

We investigate the groups generated by the sets of $CP$, $CNOT$ and $SWAP^\alpha$ (power-of-SWAP) quantum gate operations acting on $n$ qubits. Isomorphisms to standard groups are found, and using techniques from representation theory, we are able to determine the invariant subspaces of the $n-$qubit Hilbert space under the action of each group. For the $CP$ operation, we find isomorphism to the direct product of $n(n-1)/2$ cyclic groups of order $2$, and determine $2^n$ $1$-dimensional invariant subspaces corresponding to the computational state-vectors. For the $CNOT$ operation, we find isomorphism to the general linear group of an $n$-dimensional space over a field of $2$ elements, $GL(n,2)$, and determine two $1$-dimensional invariant subspaces and one $(2^n-2)$-dimensional invariant subspace. For the $SWAP^\alpha$ operation we determine a complex structure of invariant subspaces with varying dimensions and occurrences and present a recursive procedure to construct them. As an example of an application for our work, we suggest that these invariant subspaces can be used to construct simple formal verification procedures to assess the operation of quantum computers of arbitrary size.

In the last decades, the demand for steel has increased exponentially generating tons of waste impacting the environment. The most common waste in steelmaking process are slags which are produced during the rolling process of steel billets. This situation has encouraged the scientific community in finding environmentally possible ways to take advantage of this slags. In this work, we present the structural and magnetic properties of solid state recycled Q235 steel chips obtained by powder metallurgy and extrusion process from oxide scales of billets. The characterization of the recycled Q235 chips was performed by X-ray diffraction, Mossbauer spectroscopy and magnetic measurements. The X-ray diffraction reveals α-Fe as the predominant crystallographic phase and non-stoichiometric wustite in minor amount. The Mossbauer spectrum revealed a sextet associated to α-Fe phase with a hyperfine magnetic field Bhf ~ 33 T and two doublets associated with Fe2+ and Fe3+ from the non-stoichiometric wustite. Magnetic measurements show a ferromagnetic behavior because the presence of α-Fe which is the predominant phase and hysteresis is also observed under low applied fields.

A billet is a bar made from crude steel which surface contains scales which are rich in iron oxides. This study presents the carbothermal reduction of the scales formed in steel billets. The process included the reaction of the iron oxides contents with carbon (in ratio 5:1) and annealing in a tubular furnace under argon atmosphere. The occurred reactions are discussed using thermodynamic calculations and thermal analysis which indicate a three-stage reduction process Fe3O4 ➔ FeO ➔ Fe3C ➔α-Fe with intermediate reactions at the interval temperature 960 and 1300 °C. The X-ray diffraction confirms the reduction to α-Fe with minor presence of unreacted C, magnetite and wustite. Mössbauer spectroscopy analysis was performed at room temperature where a typical sextet corresponding to the dominant α-Fe is shown as well as wustite, magnetite and cementite to a lesser extent. The magnetization measurements confirm the ferromagnetic state corresponding to the α-Fe.