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The tight-binding method is used to investigate the electronic and magnetic properties of borophene nano-ribbons (BNRs) in the presence of a perpendicular magnetic field. Most BNRs exhibit metallic characteristics due to edge bands. Additionally, the appearance of Landau levels (LLs) is strongly influenced by the edge states, contrasting with the sheet platform which produces distinct LLs. We also investigated single atomic vacancy disorders in BNRs and observed localized vacancy states (LVSs) resulting from atomic disorder. Both LVSs and LLs are influenced by the edge states, underscoring that the electronic and magnetic properties of BNRs are strongly edge-dependent. This aspect is crucial for consideration in experimental, theoretical, and computational studies. [ABSTRACT FROM AUTHOR]

The creation of the United Nations Entity for Gender Equality and the Empowerment of Women, called UN Women, is the result of years of negotiations between Member States of the UN and by the movement for the defense of women in the world. It is part of the United Nations reform agenda, pooling resources and mandates for greater impact. However, gender inequalities remain deeply entrenched in every society. Women in all parts of the world experience violence and discrimination and are underrepresented in decision-making processes. High maternal mortality rates continue to be a global source of shame. For many years, the UN has faced serious challenges in its efforts to promote gender equality in the world. The objective of this project is to support the United Nations for the empowerment of Women in Africa specifically in Angola that helps in poverty reduction and entrepreneurship. [ABSTRACT FROM AUTHOR]

Experimental results obtained previously for the photoluminescence efficiency (PLeff) of Ge quantum dots (QDs) are theoretically studied. A log-log plot of PLeff versus QD diameter (D) resulted in an identical slope for each Ge QD sample only when EG ~ (D² + D)-1 . We identified that above D ≈ 6.2nm: EG ~ D-1 due to a changing effective mass (EM), while below D ≈ 4.6 nm: EG ~ D-2 due to electron/hole confinement. We propose that as the QD size is initially reduced, the EM is reduced, which increases the Bohr radius and interface scattering until eventually pure quantum confinement effects dominate at small D. [ABSTRACT FROM AUTHOR]

In this manuscript, we compute corrections to the global Casimir effect at zero and finite temperature due to rainbow gravity (parametrized by ξ ). For this, we use the solutions for the scalar field with mass m in the deformed Schwarzschild background and the corresponding quantized energies of the system, which represent the stationary states of the field and yield the stable part of the quantum vacuum energy. The analysis is made here by considering the limit for which the source mass, M, approaches zero, to verify the effects on the global Casimir effect in mini-black holes near to the Planck scale, ω P . We find a singular behavior for the regularized vacuum energy at zero temperature and for all the corresponding thermodynamic quantities when m 2 = ω P 2 / ξ , what can be seen as the limit of validity of the model. Furthermore, we show that the remnant Casimir tension over the event horizon in the limit M → 0 is finite for any temperature and all the space of parameters. In fact, we show that the remnant tension receives no corrections from rainbow gravity. This points to the fact that such a behavior may be an universal property of this kind of system. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the frequency of hypotension (based on mean arterial pressure measurements; MAP) in healthy dogs that were anaesthetised for elective desexing at Murdoch University Veterinary Hospital (MUVH). The secondary aim was to explore any association between gender, age, body mass, heart rate and anaesthetic induction agent with MAP. We hypothesised that MAP less than 60 mmHg would occur in at least 40% of healthy anaesthetised dogs. A historical cohort study was performed using anaesthetic records from dogs desexed by clinicians in the general practice service at MUVH between 2007 and 2011. Each dog was categorised according to the following criteria: I) hypotension - the lowest MAP present for at least two consecutive measurements was less than 60 mmHg, II) mild hypotension - the lowest MAP present for at least two measurements was between 60–79 mmHg and III) normotension - all MAP measurements were between 80–120 mmHg. The frequency of each category (point estimate, 95% confidence interval - CI) was calculated. Records from 188 dogs were included with 87/188 (0.46; 95% CI 0.39-0.53) categorised as hypotensive, 72/188 (0.38; 95% CI 0.31-0.45) as mildly hypotensive and 29/188 (0.15; 95% CI 0.10-0.21) as normotensive. Normotensive dogs were significantly older than hypotensive and mildly hypotensive dogs (P=0.0003 and 0.009 respectively) and hypotensive dogs had significantly lower body mass than mildly hypotensive dogs and normotensive dogs (P=0.008 and P=0.015 respectively). The frequency of hypotension was significantly higher when acepromazine and methadone was administered compared to acepromazine and morphine. The frequency of hypotension observed in the current study was at least as high as hypothesised at approximately 40%. This supports the concern that the development of hypotension is not infrequent and monitoring and managing blood pressure in healthy dogs is important. The significantly higher frequency of hypotension in younger and smaller dogs suggests modification of anaesthetic techniques may be warranted. [ABSTRACT FROM AUTHOR]

In this work, we investigate the quantum theory of light propagating in D-dimensional de Sitter space-times. To do so, we use the method of dynamic invariants to obtain the solution of the time-dependent Schrodinger equation. The quantum behavior of the electromagnetic field in this background is analyzed. As the electromagnetism loses its conformality in D ≠ 4, we point out that there will be particle production and comoving objects will feel a Bunch-Davies thermal bath. This may become important in extra dimension physics and raises the intriguing possibility that precise measurements of the Cosmic Microwave Background could verify the existence of extra dimensions. [ABSTRACT FROM AUTHOR]

We present a cryogenic source of periodic streams of micrometer-sized hydrogen and argon droplets as ideal mass-limited target systems for fundamental intense laser-driven plasma applications. The highly compact design combined with a high temporal and spatial droplet stability makes our injector ideally suited for experiments using state-of-the-art high-power lasers in which a precise synchronization between the laser pulses and the droplets is mandatory. We show this by irradiating argon droplets with multi-terawatt pulses. [ABSTRACT FROM AUTHOR]

In this work we consider q-form fields in a p-brane embedded in a D = (p+2) spacetime. The membrane is generated by a domain wall in a Randall-Sundrum-like scenario. We study conditions for localization of zero modes of these fields. The expression agrees and generalizes the one found for zero-, one-, two- and three-forms in a 3-brane. We also point out that, even without the dilaton coupling, some form fields are localized in the membrane. The massive modes are considered and the resonances are calculated using a numerical method. We find that different spaces have identical resonance structures, which we call dual spaces of resonances (DSR). [ABSTRACT FROM AUTHOR]

Tambaqui, Colossoma macropomum (Cuvier 1818), is one of the largest and most commercially important freshwater fishes in South America, attaining a body size of up to 1 m length and a mass of ≥ 30 kg. We hypothesize that the mean length of the captured tambaqui was impacted by the fishery. The present study used GIS information to map the Manacapuru Lake system and record tambaqui caught by fishermen from February 2007 to January 2008. Fork lengths of fish were measured and compared to the legal size limit of 55 cm, corresponding to the reproductive age as set by IBAMA (Brazilian Institute of the Environment and Natural Renewable Resources). Only 1% of 1271 fish measured were at or above this limit. Spatial distribution of the catch within this floodplain lake system varied, depending on the stage of the hydrologic cycle, but the greatest number of fish was caught within the Piranha Sustainable Development Reserve where fishing is prohibited by law. The results of this study indicate an acute need for enforcement of the law to avoid collapse of the fishery. [ABSTRACT FROM AUTHOR]

The (SiH3)3P hydride is introduced as a practical source for n-doping of group ivsemiconductors and as a highly-reactive delivery agent of -(SiH3)2P functionalities in exploratory synthesis. In contrast to earlier methods, the compound is produced here in high purity quantitative yields viaa new single-step method based on reactions of SiH3Br and (Me3Sn)3P, circumventing the need for toxic and unstable starting materials. As an initial demonstration of its utility we synthesized monosubstituted Me2M-P(SiH3)2(M = Al, Ga, In) derivatives of Me3M containing the (SiH3)2P ligand for the first time, in analogy to the known Me2M-P(SiMe3)2counterparts. A dimeric structure of Me2M-P(SiH3)2is proposed on the basis of spectroscopic characterizations and quantum chemical simulations. Next, in the context of materials synthesis, the (SiH3)3P compound was used to dope germanium for the first time by building a prototype p++Si(100)/i-Ge/n-Ge photodiode structure. The resultant n-type Ge layers contained active carrier concentrations of 3–4 × 1019atoms cm−3as determined by spectroscopic ellipsometry and confirmed by SIMS. Strain analysis using high resolution XRD yielded a Si content of 4 × 1020atoms cm−3in agreement with SIMS and within the range expected for incorporating Si3P type units into the diamond cubic Ge matrix. Extensive characterizations for structure, morphology and crystallinity indicate that the Si co-dopant plays essentially a passive role and does not compromise the device quality of the host material nor does it fundamentally alter its optical properties. [ABSTRACT FROM AUTHOR]

Using Monte Carlo simulations we study the Ising model with spin S = 1, 3/2 and 2 on directed Barabási-Albert and small-world networks. In this model, the order-disorder phase transition of the order parameter is well defined on small-world networks. We calculate the value of the critical temperature Tc for several values of rewiring probability p of the directed small-world network. For directed small-world networks we obtained a second-order phase transition for p = 0.2 and first-order phase transition for p = 0.8. On directed Barabási-Albert we show that phase transition do not exist for Ising model with spin S = 1, 3/2 and 2. [ABSTRACT FROM AUTHOR]

The effects of Rashba spin-orbit coupling on the physical properties of a non-interacting two-dimensional electron gas (2DEG) in presence of a tilted magnetic field are investigated. The spin-orbit and Zeeman interactions depend on the intensity and direction of the external magnetic field and we study their influence on the physical properties of the system. We obtain the energy spectrum, the density of states, the Fermi energy, and we analyze the combined effect of the Zeeman and Rashba Spin-Orbit Interaction on the transport and thermodynamic properties. [ABSTRACT FROM AUTHOR]

We study the influence of interface effects on the magnetostatic modes propagating in a coupled ferromagnetic/antiferromagnetic bilayer. We assume that the magnetic layers are thick enough to be described by the bulk parameters and they are coupled through the interaction between the magnetic moments located at the interface. We use a phenomenological approach taking into account the presence of different magnetic layers in the system to calculate the modified dynamical response of each material. We use the corrected magnetic permeability of the layers to obtain a correlation between the interface characteristics and the physical behavior of the magnetic excitations propagating in the system. [ABSTRACT FROM AUTHOR]

A microscopic model is employed to calculate the spectrum of dipole-exchange spin waves in multilayers in which thin ferromagnetic films are separated by non-magnetic spacers. Two configurations are considered: in one the films have magnetizations parallel to each other, in the other the magnetizations are antiparallel. The calculations extend a previous microscopic formalism that allows the calculation of the dipole-exchange spin wave spectrum in thin films. The results show the splitting of the frequency bands and the mode mixing caused by the dipolar interaction between the films as a function of spacer thickness. [ABSTRACT FROM AUTHOR]

Vanadium (V) has increased in the air as a component of suspended particles originated from fuel combustion. In this report, a model of inhaled V in mice was implemented to identify the effect that V has in the corpus striatum and substantia nigra, structures with high concentrations of dopamine and scarce antioxidants burden. Mice inhaled 0.02 M V2O5 1 h twice a week and were sacrificed at points from 1 to 8 weeks after inhalation, perfused, and processed for Golgi method and for tyroxine hidroxylase (TH) inmunocytochemistry. Cytological analysis consisted in counting the number of dendritic spines in 20 medium-size spiny neurons and the number of TH immunoreactive neurons in the substatia nigra pars compacta. Dendritic spine density decreased drastically after V exposure; the same was observed with the TH-positive neurons, which decreased in a time-dependent mode. No previous morphological studies about V and nervous system have been reported. The decrease in spine density and in TH-positive neurons might have functional repercussions that should be studied because the trend of this element in the atmosphere is to increase. [ABSTRACT FROM AUTHOR]

The hot-pressing operation is the final stage in medium-density fiberboard (MDF) manufacture, where the mattress of fibers is compressed and heated to promote the cure of the resin. In MDF hot-pressing, many physical, chemical and mechanical processes are involved; the complexity of this operation arises from the fact that they are coupled. A global model is presented for this operation that integrates all mechanisms involved in the panel formation (heat and mass transfer, chemical reaction and mechanical behavior). This approach results in a two-dimensional unsteady state problem, which involves the knowledge of the polymerization kinetics of the resin, the transport properties and material properties, which are position and time dependent. This dynamic model was used to predict the evolution of the variables relating to heat and mass transfer (temperature, moisture content, gas pressure and relative humidity), as well as the variables relating to mechanical behavior (pressing pressure, strain, modulus of elasticity and density). The model performance was analyzed using the typical operating conditions for the hot-pressing of MDF and the results were compared to the experimental data from an industrial MDF press. We concluded that the model could predict in an acceptable way the behavior of the key variables for the control of the pressing cycle, as well as some physico?mechanical properties of the final product. The improvement of this model will permit the scheduling of the press cycle to fulfill objectives of minimization of energy consumption, better quality of the board and increased process flexibility. [ABSTRACT FROM AUTHOR]

We report on the successful implementation and characterization of a cryogenic solid hydrogen target in experiments on high-power laser-driven proton acceleration. When irradiating a solid hydrogen filament of 10 μm diameter with 10-Terawatt laser pulses of 2.5 J energy, protons with kinetic energies in excess of 20 MeV exhibiting non-thermal features in their spectrum were observed. The protons were emitted into a large solid angle reaching a total conversion efficiency of several percent. Two-dimensional particle-in-cell simulations confirm our results indicating that the spectral modulations are caused by collisionless shocks launched from the surface of the the high-density filament into a low-density corona surrounding the target. The use of solid hydrogen targets may significantly improve the prospects of laser-accelerated proton pulses for future applications. [ABSTRACT FROM AUTHOR]

At the second order Douglas–Kroll–Hess (DKH2) level, the B3PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters (Irn, n ⩽ 8). These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n ⩽ 4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior, whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified. [ABSTRACT FROM AUTHOR]

Using radioactive isotopes produced at the CERN-ISOLDE facility, the lattice location of the implanted transition metal (TM) ions 56Mn, 59Fe and 65Ni in n-type single-crystalline hexagonal 6H-SiC was studied by means of the emission channeling technique. TM probes on carbon coordinated tetrahedral interstitial sites (TC) and on substitutional silicon sites (SSi,h+k) were identified. We tested for but found no indication that the TM distribution on SSi sites deviates from the statistical mixture of 1/3 hexagonal and 2/3 cubic sites present in the 6H crystal. The TM atoms partially disappear from TC positions during annealing at temperatures between 500 °C and 700 °C which is accompanied by an increase on SSi and random sites. From the temperature associated with these site changes, interstitial migration energies of 1.7–2.7 eV for Mn and Ni, and 2.3–3.2 eV for Fe were estimated. TM lattice locations are compared to previous results obtained in 3C-SiC using the same technique. [ABSTRACT FROM AUTHOR]

Solid state physics (SSP) research at ISOLDE has been running since the mid-1970s and accounts for about 10%–15% of the overall physics programme. ISOLDE is the world flagship for the on-line production of exotic radioactive isotopes, with high yields, high elemental selectivity and isotopic purity. Consequently, it hosts a panoply of state-of-the-art nuclear techniques which apply nuclear methods to research on life sciences, material science and bio-chemical physics. The ease of detecting radioactivity—<1 ppm concentrations—is one of the features which distinguishes the use of radioisotopes for materials science research. The manner in which nuclear momenta of excited nuclear states interact with their local electronic and magnetic environment, or how charged emitted particles interact with the crystalline lattices allow the determination of the location, its action and the role of the selected impurity element at the nanoscopic state. ISOLDE offers an unrivalled range of available radioactive elements and this is attracting an increasing user community in the field of nuclear SSP research and brings together a community of materials scientists and specialists in nuclear solid state techniques. This article describes the current status of this programme along with recent illustrative results, predicting a bright future for these unique research methods and collaborations. [ABSTRACT FROM AUTHOR]

We present a theoretical study of the charging effects in single and double layer black phosphorus quantum dots (BPQDs) with lateral sizes of 2 nm and 3 nm. We demonstrate that the charging of BPQDs are able to store up to an Nmax electron (that depends on the lateral size and number of layers in the QD), after which structural instabilities arises. For example, 3 nm wide hydrogen-passivated single layer BPQDs can hold a maximum of 16 electrons, and an additional electron causes the expelling of hydrogen atoms from the QD borders. We also calculated the addition energy (EA) spectrum. For single-layer QDs with 2 and 3 nm lateral sizes, the average EA is around 0.4 eV and 0.3 eV, respectively. For double layer QDs with the same sizes, the average EA is around 0.25 eV and 0.2 eV, respectively. [ABSTRACT FROM AUTHOR]

Original article: EPL, 117 (2017) 60001. [ABSTRACT FROM AUTHOR]

We have investigated the lattice location of implanted transition metal (TM) 56Mn, 59Fe and 65Ni ions in undoped single-crystalline cubic 3C–SiC by means of the emission channeling technique using radioactive isotopes produced at the CERN-ISOLDE facility. We find that in the room temperature as-implanted state, most Mn, Fe and Ni atoms occupy carbon-coordinated tetrahedral interstitial sites (TC). Smaller TM fractions were also found on Si substitutional (SSi) sites. The TM atoms partially disappear from ideal-TC positions during annealing at temperatures between 500 °C and 700 °C, which is accompanied by an increase in the TM fraction occupying both SSi sites and random sites. An explanation is given according to what is known about the annealing mechanisms of silicon vacancies in silicon carbide. The origin of the observed lattice sites and their changes with thermal annealing are discussed and compared to the case of Si, highlighting the feature that the interstitial migration of TMs in SiC is much slower than in Si. [ABSTRACT FROM AUTHOR]

In this paper we compute the corrections to the black-body force (BBF) potential due to spacetime geometry and topology. This recently discovered attractive force on neutral atoms is caused by the thermal radiation emitted from black bodies and here we investigate it in relativistic gravitational systems with spherical and cylindrical symmetries. For some astrophysical objects we find that the corrected BBF potential is greater than the flat case, showing that this kind of correction can be quite relevant when curved spaces are considered. Then we consider four cases: The Schwarzschild spacetime, the global monopole, the non-relativistic infinity cylinder and the static cosmic string. For the spherically symmetric case of a massive body, we find that two corrections appear: One due to the gravitational modification of the temperature and the other due to the modification of the solid angle subtended by the atom. We apply the found results to a typical neutron star and to the Sun. For the global monopole, the modification in the BBF potential is of topological nature and it is due to the central solid angle deficit that occurs in the spacetime generated by that object. In the cylindrical case, which is locally flat, no gravitational correction to the temperature exists, as in the global monopole case. However, we find the curious fact that the BBF depends on the topology of the spacetime through the modification of the azimuthal angle and therefore of the solid angle. For the static cosmic string we find that the force is null for the zero thickness case. [ABSTRACT FROM AUTHOR]

Geometrical coupling in a co-dimensional one Randall-Sundrum scenario (RS) is used to study resonances of p-form fields. The resonances are calculated using the transfer matrix method. The studied model considers the standard RS with delta-like branes, and branes generated by kinks and domain walls as well. The parameters are changed to control the thickness of the smooth brane. With this a very interesting pattern is found for the transmission coefficient. The geometrical coupling does not generate resonances for the reduced p-form in all cases considered. [ABSTRACT FROM AUTHOR]