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Heavy metal pollution in water environment has always been a hot issue in environmental pollution research. Among various removal methods of heavy metal pollution, adsorption has attracted attention because of its low cost and low secondary pollution. Montmorillonite is one of an ideal adsorption materials because of its natural pore structure and a high specific surface area. In this review, the modification methods of montmorillonite are introduced. The adsorption effect of different heavy metal ions and the main factors affecting the adsorption are discussed in detail. Meanwhile, the adsorption mechanism is intensively reviewed. The removal of Cr(VI), Cd(II), Pb(II), Cu(II), Cs(I), Co(II), Hg(II), Zn(II), Ni(II), and other nine heavy metal ions by modified montmorillonite was summarized and discussed, and the optimal pH values for different adsorbents were also different, but they were all less than 7, and the removal rates of heavy metal ions by modified montmorillonite under optimal conditions were all greater than 90%. It is concluded that the composite montmorillonite material has a great adsorption potential. Finally, it is proposed that the combination of advanced oxidation and composite montmorillonite material adsorption to remove heavy metal ions is an important direction of adsorption and removal of heavy metal ions in the water environment in the future. [ABSTRACT FROM AUTHOR]

A team of researchers at the University of Melbourne has made significant progress in developing computational methods to predict and design switchable metal complexes. By combining density functional theory and experiments, the team determined the energy range required for switching, allowing researchers to screen compounds computationally before conducting experiments. This approach can save time, money, and reduce waste in the development of switchable metal complexes. Additionally, another team at the University of Melbourne, in collaboration with ANSTO, has advanced the understanding of the electronic structure of complexes containing radicals and 4f ions. Their novel ab initio-based approach provides spatial information of the wavefunction, which is important for developing high-performance molecular magnetic materials. [Extracted from the article]

The mapping and visualization of metal ions in tissue specimens by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is technically challenging. LA-ICP-MS enrich the diagnostic tools in experimental and clinical studies that aim to detect and quantify various metal disorders. We have recently developed a new software tool, i.e., ELAI, allowing the reconstruction of metal distribution maps and high quality scaled images from Microsoft Excel data lists representing the typical output of line by line scans in LA-ICP-MS measurements. ELAI is organized modularly and the individual software features offer many easy to use possibilities for LA-ICP-MS data analysis and interpretation in daily routine use. This visualization tool is simply transferable to other analysis systems and the image files prepared can be read out by standard region of interest handling software such as Image J. We here describe a novel feature designed for ELAI in which different colouration codes for the different metals are applied, enabling a good regional allocation of a specific metal within the tissues. The advantages of this novel software component are demonstrated by measurements performed in mouse brain and liver tissue samples of an experimental model of cooper overload disease (e.g., Wilson's disease). Particularly, we show that the digital image overlay is highly helpful for visualization of regional trace metal accumulation and in interpreting of metalinduced tissue damage. Our data demonstrate that the novel image overlay feature is a significant add-on for those practitioners employing LA-ICP-MS imaging for quantification and visualization of metal accumulation and deposits in all different kinds of tissue samples. [ABSTRACT FROM AUTHOR]

Iridium ions near 4f-5s level crossings are the leading candidates for a new type of atomic clocks with a high projected accuracy and a very high sensitivity to the temporal variation of the fine structure constant a. To identify spectra of these ions in experiment accurate calculations of the spectra and electromagnetic transition probabilities should be performed. Properties of the 4f-core-excited states in Ir16+,Ir17+, and Ir18+ ions are evaluated using relativistic many-body perturbation theory and Hartree-Fock-relativistic method (COWAN code). We evaluate excitation energies, wavelengths, oscillator strengths, and transition rates. Our large-scale calculations included the following set of configurations: 4f145s,4f145p,4f135s²,4f135p²,4f135s5p,4f125s²5p, and 4f125s5p² in Pm-like Ir16+; 4f14,4f135s,4f135p,4f125s²,4f125s5p, and 4f125p² in Nd-like Ir17+; and 4f13,4f125s,4f125p,4f115s², and 4f115s5p in Pr-like Ir18+. The 5s-5p transitions are illustrated by the synthetic spectra in the 180-200 Å range. Large contributions of magnetic-dipole transitions to lifetimes of low-lying states in the region below 2.5 Ry are demonstrated. [ABSTRACT FROM AUTHOR]

We investigate the role of electron-correlation effects in calculations of the electric-dipole polarizabilities a of elements belonging to three different groups (12-14) of the periodic table. To understand the propagation of the electron-correlation effects at different levels of approximations, we employ the relativistic many-body methods developed, based on first principles, at mean-field Dirac-Fock (DF), third-order many-body perturbation theory [MBPT(3)], random-phase approximation (RPA), and singly and doubly approximated coupled-cluster methods at the linearized (LCCSD) and nonlinearized (CCSD) levels. We observe a variance in the trends of the contributions of the correlation effects in a particular group of elements through the many-body method used; however, they resemble a similar tendency among the iso-electronic systems. Our CCSD results are within sub-1% agreement with the experimental values which are further ameliorated by including the contributions from the important triple excitations (CCSDPT method). [ABSTRACT FROM AUTHOR]

We report the implementation of the equation-of-motion coupled-cluster (EOMCC) method in the fourcomponent relativistic framework with a spherical atomic potential to generate the excited states from a closedshell atomic configuration. This theoretical development will be very useful in carrying out high-precision calculations of various atomic properties in many atomic systems. We employ this method to calculate the excitation energies of many low-lying states in a few Ne-like highly charged ions, such as Cr XV, Fe XVII, Co XVIII, and Ni XIX ions, and compare them against their corresponding experimental values to demonstrate the accomplishment of the EOMCC implementation. The ions considered are appropriate to substantiate accurate inclusion of the relativistic effects in the evaluation of atomic properties and are also interesting for astrophysical studies. Investigation of the temporal variation of the fine-structure constant (a) obtained from astrophysical observations is a modern research problem for which we also estimate the a sensitivity coefficients in the above ions. [ABSTRACT FROM AUTHOR]

We experimentally and theoretically study the coherent quantum control of green emission in Er3+-doped glass by π-phase-shaped 800-nm femtosecond laser pulses. The experimental results show that the green emission intensity is enhanced over the transform-limited pulse by n-phase-shaped pulses as the laser field increases to several 1012 W/cm². Coherent control of multiphoton absorption is studied based on the fourth-order perturbation theory, and the theoretical results accord well with the experimental observations. [ABSTRACT FROM AUTHOR]

In this study, accurate static dipole polarizability and hyperpolarizability are calculated for Al+ ground state 3s² ¹S0 and excited state 3s3p ³PJ with J=0,1,2 . The finite-field computations use energies obtained with the relativistic configuration interaction approach and the relativistic coupled-cluster approach. Excellent agreement with previously recommended values is found for the dipole polarizability of Al+ ground state 3s2 ¹S0 and excited state 3s3p ³P0 as well as the hyperpolarizability of the ground state 3s 2 ¹S0 . The recommended values of the dipole polarizability of the Al+ 3s3p ³P1 and ³P2 and the hyperpolarizability of Al+ 3s3p ³P0, ³P1, and ³P2 are also given. The impacts of the relativity and spin-orbit coupling are elucidated by analyzing the angular momentum dependence of the dipole polarizability and the hyperpolarizability, and comparing the fully and scalar relativistic calculated data. It is shown that the impact of the relativity and spin-orbit coupling are small for the dipole polarizability but become significant for the hyperpolarizability. Finally, the blackbody radiation shifts contributed by the dipole polarizability and hyperpolarizability, respectively, are evaluated for transitions of Al+ 3s 2 ¹S0 to 3s3p ³PJ with J=0,1,2 . [ABSTRACT FROM AUTHOR]

We have developed a one-electron detachment theory from a closed-shell atomic configuration in the relativistic Fock-space coupled-cluster ansatz. Using this method, we determine sensitivity coefficients to the variation of the fine-structure constant in the first three important low-lying transitions of the astrophysically interesting highly charged Mn IX, Fe X, Co XI, and Ni XII ions. The potential of this method has been assessed by evaluating the detachment energies of the removed electrons and determining the lifetimes of the atomic states in the above ions. To account for the sensitivity of the higher-order relativistic effects, we have used the four-component wave functions of the Dirac-Coulomb-Breit Hamiltonian with the leading-order quantum electrodynamics (QED) corrections. A systematic study has been carried out to highlight the importance of the Breit and QED interactions in the considered properties of the above ions. [ABSTRACT FROM AUTHOR]

The article discusses a study by Markus Ralser and colleagues which suggests that the Krebs cycle could have existed prior to life itself on Earth. Topics include the study's suggestions that a simple, inorganic molecule must have existed naturally in early Earth's oceans in order for the Krebs cycle to have occurred spontaneously, Ralser's findings that metal ions an drive two parts of a cell's metabolism, and the lack of knowledge regarding how the elements were brought together to make a living cell.

In this work we report on ah initio theoretical results for the magnetic-field-induced 2s2p³P0→ 2s2...IS0 El transition for ions in the beryllium isoelectronic sequence between Z = 5 and 92. It has been proposed that the rate of the E1M1 two-photon transition 2s 2p³P0 → 2s2I S0 can be extracted from the lifetime of the ³P0 state in Be-like ions with zero nuclear spin by employing resonant recombination in a storage ring. This experimental approach involves a perturbing external magnetic field. The effect of this field needs to be evaluated in order to properly extract the two-photon rate from the measured decay curves. The magnetic-field-induced transition rates are carefully evaluated, and it is shown that, with a typical storage-ring field strength, it is dominant or of the same order as the El Ml rate for low- and mid-Z ions. Results for several field strengths and ions are presented, and we also give a simple Z-dependent formula for the rate. We estimate the uncertainties of our model to be within 5% for low- and mid-Z ions and slightly larger for more highly charged ions. Furthermore we evaluate the importance of including both perturber states, ³P1 and ¹P1, and it is shown that excluding the influence of the ¹P1 perturber overestimates the rate by up to 26% for the mid-Z ions. [ABSTRACT FROM AUTHOR]

We apply an independent electron model to study q-fold target-charge-state production in 25-600 keV/nucleon B2+-Ne collisions for which experimental and theoretical results were published recently [ W. Wolff et al. Phys. Rev. A 84 042704 (2011)]. The model treats projectile and target electrons using a common potential and makes use of a single-determinant wave function for the combined system. The calculated total cross sections for positive recoil ion production as well as for Neq+ production (q=1,...,4) determined in coincidence with an unchanged projectile charge state agree well with experiment where available, i.e., in the 30-400 keV/nucleon energy range. At energies below 200 keV/nucleon the projectile electrons are shown to play a crucial role in reproducing the experimental data for q=1,...,4. For the q≥2 channels the inclusion of projectile electron contributions is needed even at energies above 200 keV/nucleon in order to reproduce the experimental data. As expected, the predictions for the q=5 recoil charge state overestimate the experimental data due to a failure of the independent electron model for this extreme channel. [ABSTRACT FROM AUTHOR]

Using resonant two-step laser excitation of trapped 232Th+ ions, we observe 43 previously unknown energy levels within the energy range from 7.3 to 8.3 eV. The high density of states promises a strongly enhanced electronic bridge excitation of the 229mTh nuclear state that is expected in this energy range. From the observation of resonantly enhanced three-photon ionization of Th+, the second ionization potential of thorium can be inferred to lie within the range between 11.9 and 12.3 eV. Pulsed laser radiation in a wide wavelength range from 237 to 289 nm is found to provide efficient photodissociation of molecular ions that are formed in reactions of Th+ with impurities in the buffer gas, leading to a significantly increased storage time for Th+ in the ion trap. [ABSTRACT FROM AUTHOR]

Parity-nonconservation (PNC) amplitudes are calculated for the 7s-6d3/2 transitions of the francium isoelectronic sequence (Fr, Ra+, Ac2+, Th3+, Pa4+, U5+, and Np6+) and for the 6s-5d3/2 transitions of the cesium isoelectronic sequence (Cs, Ba+, La2+, Ce3+, and Pr4+). We show in particular that isotopes of La2+, AC2+, and Th3+ ions have strong potential in the search for new physics beyond the standard model: The PNC amplitudes are large, the calculations are accurate, and the nuclei are practically stable. In addition, 232Th3+ ions have recently been trapped and cooled [Campbell et al., Phys. Rev. Lett. 102, 233004 (2009)]. We also extend previous works by calculating the s-s PNC transitions in Ra+ and Ba+ and provide calculations of several energy levels, and electric dipole and quadrupole transition amplitudes for the Fr-like actinide ions. [ABSTRACT FROM AUTHOR]

In the present work, we explore the thermal entanglement between spin and orbital angular momentum in a rare-earth ion. A witness, based on the magnetic susceptibility and capable of revealing entanglement between these two angular momenta of different nature, is introduced. We found entanglement temperatures of 322 K for promethium and 715 K for samarium. These high temperatures make interesting the use of rare-earth in applications of quantum-information processes at room temperature. [ABSTRACT FROM AUTHOR]

Using perturbed relativistic coupled-cluster (PRCC) theory we compute the ground-state electric dipole . polarizability, a, of doubly ionized alkaline earth metal ions Mg2+, Ca2+, Sr2+, Ba2+, and Ra2+. In the present work we use the Dirac-Coulomb-Breit atomic Hamiltonian and we also include the Uehling potential, which is the leading-order term in the vacuum polarization corrections. We examine the correction to the orbital energies arising from the Uehling potential in the self-consistent field calculations as well as perturbatively. Our results for a are in very good agreement with the experimental data, and we observe a change in the nature of the orbital energy corrections arising from the vacuum polarization as we go from Mg2+ to Ra2+. [ABSTRACT FROM AUTHOR]

We use the previously developed radiative potential method to calculate quantum electrodynamic (QED) corrections to energy levels and electric dipole transition amplitudes for atoms which are used for the study of the parity nonconservation (PNC) in atoms. The QED shift in energies and dipole amplitudes leads to noticeable change in the PNC amplitudes. This study compliments the previously considered QED corrections to the weak matrix elements. We demonstrate that the QED corrections due to the change in energies and dipole matrix elements are comparable in value to those due to the change in weak matrix elements and therefore must be included. [ABSTRACT FROM AUTHOR]

Charge-transfer cold Yb+ + Rb collision dynamics is investigated theoretically using high-level ab initio potential energy curves, dipole moment functions, and nonadiabatic coupling matrix elements. Within the scalar-relativistic approximation, the radiative transitions from the entrance A'Σ+ to the ground X'Σ+ state are found to be the only efficient charge-transfer pathway. The spin-orbit coupling does not open other efficient pathways, but alters the potential energy curves and the transition dipole moment for the A-X pair of states. The radiative, as well as the nonradiative, charge-transfer cross sections calculated within the 10-3--10 cm-1 collision energy range exhibit all features of the Langevin ion-atom collision regime, including a rich structure associated with centrifugal barrier tunneling (orbiting) resonances. Theoretical rate coefficients for two Yb isotopes agree well with those measured by immersing Yb+ ions in an ultracold Rb ensemble in a hybrid trap. Possible origins of discrepancy in the product distributions and relations to previously studied similar processes are discussed. [ABSTRACT FROM AUTHOR]

The article focuses on the initiative of the Defence Science and Technology Organisation (DSTO) to develop a field method for detection of metal deactivator additive (MDA) in jet fuel so fuel-management decisions can be made directly. It discusses the possibility of generating metal-MDA ligand complexes by altering the metal ion reacted with MDA using simple open column chromatography. It examines the use of MDA detection kits on military bases and its usefulness in jet fuel quality control.

The nonradiative charge-transfer processes for the Be3+(ls) + H(Is) collisions are investigated by the quantummechanical molecular orbital close-coupling" method in the energy range of 0.01-10 keV/u. The radiative charge-transfer cross sections are calculated by the optical potential and semiclassical methods in the energy range 10-6--10³ eV/u. The needed molecular data are obtained by the ab initio multireference single- and double-excitation configuration interaction method. Total and state-selective cross sections are presented and compared with other available theoretical data. Our calculation agrees well with the atomic orbital close-coupling results of Liu et al. [L. Liu, D. Jakimovski, J. G. Wang, and R. K. Janev, J. Phys. B 43, 144005 (2010)], but there exist some discrepancies with the semiclassical molecular orbital close-coupling results of Shimakura [N. Shimakura, J. Phys. B 21, 2485 (1988)]. The present results show that the capture to Si2+(1s3l) states is dominant in the whole energy range with the exception of a narrow range of 2-4 keV/u. Rotational couplings play an important role not only in the state-selective cross sections, but also in the total charge-transfer results. At energies below 40 eV/u, the radiative charge transfer exceeds the nonradiative process. [ABSTRACT FROM AUTHOR]

The ionization and fragmentation of trapped protonated dGCAT oligonucleotides upon interaction with energetic photons {hv = 10-570 eV) and keV Cq+ ions was investigated by means of time-of-flight mass spectrometry. The observed fragmentation patterns are dominated by protonated and nonprotonated nucleobase ions and fragments of the deoxyribose moiety. Fragments exceeding the size of nucleosides are almost completely absent. Absorption of VUV photons as well as interaction with keV ions predominantly involves ionization or excitation of molecular valence electrons and accordingly the observed fragmentation patterns exhibit qualitatively similar features. Soft-x-ray-induced ionization of core level electrons accompanied by subsequent emission of an Auger electron shifts the fragment distributions towards smaller masses. This systematic study allows for insights into differences and similarities between ion- and photon-induced excitation and fragmentation mechanisms. In particular, the crucial role of the deoxyribose moiety for radiation-induced DNA damage that was predicted on the basis of gas-phase experiments using isolated deoxyribose molecules is confirmed. [ABSTRACT FROM AUTHOR]

Excitation energies of thens, np, nd, and nf (n ≼ 9) states in Li-like Be+ are evaluated within the framework of relativistic many-body theory. First-, second-, third-, and all-order Coulomb energies and first- and second-order Breit corrections to the energies are calculated. Two alternative treatments of the Breit interaction are investigated. In the first approach, we omit Breit contributions to the Dirac-Fock potential and evaluate Coulomb and Breit-Coulomb corrections through second order perturbatively. In the second approach, we include both Coulomb and Breit contributions on the same footing via the Breit-Dirac-Fock potential and then treat the residual Breit and Coulomb interactions perturbatively. The results obtained from the two approaches are compared and discussed. All-order calculations of reduced matrix elements, oscillator strengths, transition rates, and lifetimes are given for levels up to n = 9. Electric-dipole (2s-np), electric-quadrupole (2s-nd), and electric-octupole (2s-nf) matrix elements are evaluated in order to obtain the corresponding ground-state multipole polarizabilities using the sum-over-states approach. Recommended values are provided for a large number of electric-dipole matrix elements. Scalar and tensor polarizabilities for the ns, np1/2, np3/2, nd3/2, and nd5/2 states with n ≼ 9 are also calculated. The scalar hyperpolarizability for the ground 2s state is evaluated and compared with the result of a nonrelativistic calculation. [ABSTRACT FROM AUTHOR]

Measurements of extreme ultraviolet radiation from highly charged gadolinium ions were made at the National Institute of Standards and Technology. The ions were produced and confined in an electron-beam ion trap (EBIT), and the spectra were recorded with a flat-field grazing-incidence spectrometer in the wavelength range 3-17 nm. Ionization stages from Rb-like to Cu-like gadolinium were selected by tuning the electron-beam energies between 0.97 and 1.7 keV. Strong intrashell η = 4-n = 4 transitions were identified by performing detailed collisional-radiative modeling of the EBIT plasma. A total of 73 spectral features were recorded, including 59 new identifications. [ABSTRACT FROM AUTHOR]

In order to study ultracold charge-transfer processes in hybrid atom-ion traps, we have mapped out the potential-energy curves and molecular parameters for several low-lying states of the Rb, Yb+ system. We employ both a multireference configuration interaction and a full configuration interaction (FCI) approach. Turning points, crossing points, potential minima, and spectroscopic molecular constants are obtained for the lowest five molecular states. Long-range parameters, including the dispersion coefficients, are estimated from our ab initio data. The separated-atom ionization potentials and atomic polarizability of the ytterbium atom (&agr;d -- 128.4 atomic units) are in good agreement with experiment and previous calculations. We present some dynamical calculations for (adiabatic) scattering lengths for the two lowest (Yb, Rb+) channels that were carried out in our work. However, we find that the pseudopotential approximation is rather limited in validity and only applies to nK temperatures. The adiabatic scattering lengths for both the triplet and singlet channels indicate that both are large and negative in the FCI approximation. [ABSTRACT FROM AUTHOR]

To provide reliable reference results for various components of the electron correlation energies of Zn2+ and Zn, which play a similar role for 3d-electron systems as Ne and Mg do for lighter atoms, we have performed extensive calculations of the all-electron correlation energy and of its various components with several state-of-the-art ab initio techniques. Two pairs of basis-set sequences that systematically converge to the complete basis set (CBS) limit have been employed in the calculations. One pair [cc-pVnZ and aug-cc-pVnZ (correlation consistent polarized valence «-zeta and augmented cc-pVnZ with n = D, T, Q, 5, 6(--k))] is oriented towards the description of valence electron correlation. The second pair of sequences [cc-pCCVnZ and aug-cc-pCCVnZ (core core-valence ra-zeta, with n = D, T, Q, 5, 6(-k))] is developed for the description of all-electron correlation effects. The correlation energies have been determined with second-order Møller-Plesset perturbation theory (MP2) and several single-reference coupled-cluster (CC) methods. The present correlation energies represent accurate post-MP2 correlation energies for closed-shell atoms including 3d electrons both at the all-electron and subshell levels and should be useful benchmark results for various transitions. We have also employed the present results for assessments of the focal-point approximation (FPA), broadly used in approximations of difference correlation effects for molecular interaction problems, in applications aiming at estimating correlation effects in heavier atoms. Our results indicate that for the systems considered, the magnitudes of the MP2 correlation energies overestimate the magnitudes of the CC values for all electrons correlated as well as of their various subsets. For the all-electron correlation energies of the Zn atom, our result confirms the finding of S. P. McCarthy and A. J. Thakkar [J. Chem. Phys. 134, 044102 (2011)] obtained by means of non-ab> initio approaches for all heavy closed-shell atoms from Zn to Rn. We have shown that for both Zn2+ and Zn this overestimation is directly caused by the presence of the 3d10 electron configuration. [ABSTRACT FROM AUTHOR]

The ground-state hyperfine splittings of laser-cooled 113Cd+ and 111Cd+ ions confined in a linear Paul trap have been measured to be 15 199 862 854.96(0.12) Hz and 14 530 507 349.9(1.1) Hz, respectively, using a microwave-optical double-resonance technique. The results for 113Cd+ agrees with previous measurements very well, and the precision of the 111Cd+ is improved by 7 orders of magnitude compared to the best results reported in the literature. The possibility of a microwave frequency standard based on laser-cooled cadmium ions is also discussed. [ABSTRACT FROM AUTHOR]

We present a quantum memory protocol that allows us to Store light in ensembles of two-level atoms, e.g., rare-earth-metal ions doped into a crystal, by modulating the refractive index of the host medium of the atoms linearly in time. We show that under certain conditions the resulting dynamics is equivalent to that underlying the gradient echo memory protocol, which relies on a spatial gradient of the atomic resonance frequencies. We discuss the prospects for an experimental implementation. [ABSTRACT FROM AUTHOR]

The first flavor-tagged amplitude analysis of the decay D0 to the self-conjugate final state K+ K- π+ π- is presented. Approximately 3000 signal decays are selected from data acquired by the CLEO II.V, CLEO III, and CLEO-c detectors. The three most significant amplitudes, which contribute to the model that best fits the data, are φ p0, K1(1270)±K±, and nonresonant K+ K- π+ π- . Separate amplitude analyses of D0 and D0 candidates indicate no CP violation among the amplitudes at the level of 5% to 30% depending on the mode. In addition, the sensitivity to the CP-violating parameter γ/φ3 from a sample of 2000 B+ → D0(K+ K- π+ π-)K+ decays, where D is a D0 or D0, collected at LHCb or a future flavor facility, is estimated to be (11.3 ± 0.3)° using the favored model. [ABSTRACT FROM AUTHOR]

In this work, we recalculate the charmless pure annihilation decays Bs → π+π- and B0 → K+K- by using the perturbative QCD (pQCD) factorization approach, and compare the pQCD predictions with currently available experimental measurements. By numerical calculations and phenomenological analysis, we found the following results: (a) one can provide a consistent pQCD interpretation for both the measured branching ratio Br(B0s → π+π-) and Br(B0d → K+K-) simultaneously; (b) the pQCD predictions for Br(B0s → π+π-) obtained by different authors are well consistent with each other; (c) our new pQCD prediction for Br(B0d → K+K-) agrees well with the measured values from CDF and LHCb Collaborations; and (d) the CP-violating asymmetry ACP(B0d → K+K-) ≈ 19%, which is large and may be detected at the LHCb and future Super-B factory experiments. [ABSTRACT FROM AUTHOR]

A search for the X(4140) state in B+ → J/ψϕK+ decays is performed with 0.37 fb−1 of pp collisions at √s = 7 TeV collected by the LHCb experiment. No evidence for this state is found, in 2.4σ disagreement with a measurement by CDF. An upper limit on its production rate is set, B(B+ → X(4140)K+) × B(X(4140)→J/ψϕ)/B(B+ → J/ψϕK+) < 0.07 at 90% confidence level. [ABSTRACT FROM AUTHOR]

We have calculated electric dipole polarizabilities of the 3s2 1S0, 3s3p3P0, and 3s3p1P1 states of the Si2+ ion using the recently developed configuration interaction + all-order method. A detailed evaluation of the uncertainties of the final results is carried out. Our value for the ground-state electric dipole polarizability 11.670(13) a.u. is in excellent agreement with the resonant excitation Stark ionization spectroscopy value 11.669(9) a.u. [Komara et al, J. Phys. B 38, 87 (2005); Mitroy, Phys. Rev. A 78, 052515 (2008)]. This paper represents a benchmark test of theory and experiment in divalent atoms. The near cancellation of the ns2 1S0 ground state and the lowest nsnp3P0 polarizabilities previously observed in B+, Al+, In+, Tl+, and Pb2+ is also found in the Si2+ ion. [ABSTRACT FROM AUTHOR]

The double manganite CaCu3Mn4O12 doped with119Sn atoms (∼ 1 at.% with respect to manganese atoms) was studied by use of Mossbauer spectroscopy. Formally tetravalent Sn4+ ions substitute for isovalent manganese ions in the octahedral (Mn4+06) polyhedra. The covalency effects on the magnetic interactions like superexchange in Cu2+-0-Mn4+ and Mn4+-0-Mn4+ bonds and supertransferred hyperfine interactions of the 119 probe atoms in the manganite structure are discussed. Using a semiquantitative nearest-neighbor cluster model relating the hyperfine magnetic field on the mSn nuclei (HSn = 105 kOe at T = 77 K) to covalency parameters and angle characterizing the Sn-O-A/ (M = Cu, Mn) bonds, it has been shown how such an analysis of supertransferred hyperfine interactions of tin probe ions can get fruitful information about strength and sign of the superexchange interactions between Mn4+ and Cu2+ magnetic ions. A consistent description of the results in the framework of the Weiss molecular field model considering the specific local environment of tin atoms has made it possible to estimate exchange integrals: JcuMii = --51.1 ± 0.3 K and JMnMn = -0.6 ± 0.2 K. [ABSTRACT FROM AUTHOR]

The platinum channel (&ngr;e or &&ngr;macr;e appearance) has been proposed at neutrino factories as an additional channel that could help in lifting degeneracies and improving sensitivities to neutrino oscillation parameters, viz., &thetas13, &dgr;CP, mass hierarchy, deviation of &thetas;23 from maximality and its octant. This channel corresponds to &ngr;&mgr; → &ngr;e (&&ngr;macr;&mgr; → &ngr;¯) oscillations of the initial neutrino flux, with the subsequent detection of electrons (positrons) from charged current interactions of the &ngr;e ( &ngr;e ) in the detector. For small values of &thetas;13, the dominant &ngr;&mgr; → &ngr;&tgr; (&&ngr;macr;&mgr; → &&ngr;macr;&tgr;) oscillation results in this signal being swamped by electrons arising from the leptonic decay of taus produced in charge-current interactions of &ngr;&tgr; (&&ngr;macr;&tgr;) with the detector. We examine for the first time the role of this tau contamination to the electron events sample and find that it plays a significant role in the platinum channel compared to other channels, not only at high-energy neutrino factories but surprisingly even at low energy neutrino factories. Even when the platinum channel is considered in combination with other channels such as the golden (muon appearance) or muon disappearance channel, the tau contamination results in a loss in precision of the measured parameters. [ABSTRACT FROM AUTHOR]

We report on a nonperturbative R-matrix with PseudoStates (RMPS) calculation for the electron-impact ionization cross section of the ground state of Al2+. We include both the direct ionization of the 3.s and 2p subshells and the indirect ionization from the 2p subshell. This calculation, thus, includes extra decay channels for the indirect-ionization process not included in previous RMPS calculations. This lowers the total-ionization cross section, resulting in closer agreement with the most recent experimental measurements. This calculation also shows better agreement with the position and height of the resonant-excitation double autoionization features seen in the experiment. [ABSTRACT FROM AUTHOR]

We use relativistic Hartree-Fock and correlation potential methods to calculate nuclear spin-dependent, parity-nonconserving amplitudes (dominated by the nuclear anapole moment) between hyperfine structure components of the ground state of odd isotopes of K, Rb, Cs, Ba+, Yb+, Tl, Fr, and Ra+. The results will be used for interpretation of current and future measurements. [ABSTRACT FROM AUTHOR]

We carry out a systematic study of Pb III properties using a hybrid method that combines configuration interaction and linearized coupled-cluster approaches. The calculations start from a [Xe]4f145d10 Dirac-Fock potential. Excitation energies and lifetimes of the 6p2, 6sns, 6snp, and 6snd (n ≤ 9) states are evaluated. Reduced matrix elements, oscillator strengths, and transition rates are determined for allowed electric-dipole transitions including these states. Extensive comparison with other theoretical and experimental values is carried out. Electric-dipole polarizabilities of the 6s2 1So, 6s6p 3P0, and 6s6p3P1 states in Pb m and ground state polarizability of Pb4+ are reported. [ABSTRACT FROM AUTHOR]

We perform laser spectroscopy of Yb+ ions on the 4f146s 2S1/2-4f135d6s 3D[3/2]1/2 transition at 297 nm. The frequency measurements for 170Yb+, 172Yb+, 174Yb+, and 176Yb+ reveal the specific mass shift as well as the field shifts. In addition, we demonstrate laser cooling of Yb+ ions using this transition and show that light at 297 nm can be used as the second step in the photoionization of neutral Yb atoms. [ABSTRACT FROM AUTHOR]

The isotope shift of the bound-bound electric dipole transition at 1162.75 nm in the osmium anion was measured by high-precision collinear laser spectroscopy. The transition was observed in all naturally occurring isotopes, including 184Os- with a natural abundance of 0.02%. We combined the data with our prior measurements of the hyperfine structure in l87Os- and l89Os- and used them to determine experimental values for the isotope shift coefficients. The normal mass shift, specific mass shift, and field shift coefficients were found to be MNMS = 141.4 GHz u, MSMS = 2.4(12.6) THz u, and F = 16.2(9.9) GHz fm-2, respectively. Theoretical values for the AfSMS and F parameters were calculated based on a series of relativistic configuration interaction computations and a Fermi-like charge distribution and found to be in good agreement with the experimental values. [ABSTRACT FROM AUTHOR]

Fully relativistic distorted-wave theory has been applied to study the electron-impact excitation of the ns1/2-np1/2 and ns1/2-np3/2 resonance transitions of singly charged metal ions with one valence electron, viz., Mg+ (n = 3), Ca+ (n = 4), Zn+ (n = 4), Cd+ (n = 5), and Ba+ (n = 6). Calculations are performed in the range of incident electron energies up to 300 eV for differential and integrated cross sections as well as for the linear polarization of the photon emissions following the decay of excited np3/2 states. Results are compared with the available experimental data and previous nonrelativistic theoretical calculations. Moreover, analytic fits to our integrated cross sections are provided for potential applications in modeling plasma sources and environments. [ABSTRACT FROM AUTHOR]

A partial cDNA sequence was obtained from the human blood fluke, Schistosoma mansoni using a signal sequence trap approach. The full-length cDNA was cloned and termed Sm-7TM. The corresponding open reading frame had 7 membrane spanning domains and shared identity with a small, novel group of seven transmembrane (7TM) receptors from vertebrates and invertebrates, including the human ee3 receptor – a heptahelical protein implicated in neuronal signalling. Phylogenetic analysis of this novel family showed that the Sm-7TM ORF formed a clade with exclusively invertebrate sequences. Based on topology modelling with ee3, Sm-7TM was predicted to possess an intracellular C-terminal tail, which was expressed as a soluble thioredoxin fusion protein (Sm-7TMC) in Escherichia coli and purified using metal ion-affinity chromatography. A polyclonal antiserum against this domain was used to detect Sm-7TM in detergent-soluble parasite extracts and to immunolocalize the receptor to the tegument of adult S. mansoni. [ABSTRACT FROM PUBLISHER]

Theoretical treatments forecast that bistable CMOS devices using electronic charge as a state variable will operate at their maximum thermal dissipation limit possibly as early as 2012. The problem is further compounded by increasing manufacturing challenges associated with the ever decreasing logic switch dimensions. These challenges require the development of new fabrication strategies that replace or complement current top-down lithography with bottom-up protocols using controlled self-assembly of nanomaterial building blocks. To answer some of these issues, this paper focuses on a new device paradigm consisting of an arene-metal-arene conformational switch, addressable through capacitive, inductive, or resonant-tunneling field coupling. The operating principle is based on voltage-tunable modulation in quantum electron transmission. The switch is open (OFF) when the metal ion is displaced to a position at a C-H bond on the arene ring due to an externally applied bias. Conversely, when the external bias is removed, the metal ion moves to an axis- symmetric position on the arene ring, and the switch is closed (ON). The paper presents a summary of the architecture, operating principle, and advantages of the conformational switch, along with associated findings from proof-of-concept theoretical and experimental studies of its target specifications and performance. The paper also discusses opportunities and challenges related to the integration of conformational switches into hybrid CMOS-molecular and monolithic (all molecular) circuits. [ABSTRACT FROM AUTHOR]

This study investigated a new effective method for controlling the capsalid monogenean Neobenedenia girellae. We examined in vitro and in vivo the effect on the percentage survival of N. girellae in buffers containing different metallic ions. Decreased survival was observed in buffer solutions lacking two ions. In particular, the percentage survival of N. girellae was significantly decreased after 10 min exposure to buffer containing neither Ca2+ nor Mg2+. Transmission electron microscopic observations showed that treatment with this buffer disrupted intercellular junctions. This significant effect on percentage survival of N. girellae using Ca2+/Mg2+-free buffer was confirmed in an in vivo assay. Ca2+/Mg2+-free buffer had no effect on the condition of the host, spotted halibut Verasper variegates (Pleuronectidae). These results suggest that treatment with Ca2+/Mg2+-free buffer is a new effective control method, which could replace existing control methods. [ABSTRACT FROM AUTHOR]

This article presents news clippings related to textile industry. Cutting-edge fabrics worth their weave will function as a personal climate control system, automatically regulating temperature and moisture. Fiber manufacturers are infusing special powers into some synthetics at the primordial soup level, before the fibers are even extruded. Clothing makers have discovered that adding silver ions to molten polyester is the most effective way to create antimicrobial clothing. Timberland's new shell technology in its Pro Sports Series Master Rack boot offers scent control, superior waterproof protection and abrasion resistance with a new shell system.

The total electron-impact single-ionization cross sections of Mg and Al+ have been calculated by Ludlow et al. [Phys. Rev. A 79, 032715 (2009)] using the time-dependent close-coupling and R-matrix-with-pseudostates methods. The cross-section results were found to be in good agreement with each other, but substantially smaller than those reported by several experiments. We apply the convergent close-coupling method to the problem and find a much improved agreement with experiment. [ABSTRACT FROM AUTHOR]

Nickel, cadmium, cobalt, and arsenic compounds are well-known carcinogens to humans and experimental animals. Even though their DNA-damaging potentials are rather weak, they interfere with the nucleotide and base excision repair at low, noncytotoxic concentrations. For example, both water-soluble Ni(II) and paniculate black NiO greatly reduced the repair of DNA adducts induced by benzo[a]pyrene, an important environmental pollutant.” Furthermore, Ni(II), As(IH), and Co(II) interfered with cell cycle progression and cell cycle control in response to ultraviolet C radiation. As potential molecular targets, interactions with so-called zinc finger proteins involved in DNA repair and/or DNA damage signaling were investigated. We observed an inactivation of the bacterial formamidopyrimidine-DNA glycosylase (Fpg), the mammalian xeroderma pigmentosum group A protein (XPA), and the poly(adenosine diphosphate-ribose)polymerase (PARP). Although all proteins were inhibited by Cd(II) and Cu(II), XPA and PARP but not Fpg were inhibited by Co(II) and Ni(ll). As(III) deserves special attention, as it inactivated only PARP, but did so at very low concentrations starting from 10 nM. Because DNA is permanently damaged by endogenous and environmental factors, functioning processing of DNA lesions is an important prerequisite for maintaining genomic integrity; its inactivation by metal compounds may therefore constitute an important mechanism of metal-related carcinogenicity. [ABSTRACT FROM AUTHOR]

Reports on U.S. scientists' development of a compound called Venus Flytrap Cluster (VFC), which is effective in treating colorectal cancer. Cage of boron and carbon atoms in VFC, which acts as a carrier for a radioactive metal ion trapped inside; Radiometal ion's ability to kill a cancer cell; Stability of VFC; Resistance to biological degradation; Cluster-to-metal bonds preventing the radiometal from being released prematurely.

The article focuses on a study led by astrophysicist Joseph Grebowsky for analysis of metallic ions associated with the Earth's atmosphere along with the Mars; and observation of mixture of heavier iron ions and lighter magnesium ions due to absence of magnetic field.

We present additional magic wavelengths (λmagic) for the clock transitions in the alkaline-earth-metal ions, considering circular polarized light, aside from our previously reported values [Kaur et al., Phys. Rev. A 92, 031402(R) (2015)] for linearly polarized light. Contributions from the vector component to the dynamic dipole polarizabilities [αd(ω)] of the atomic states associated with the clock transitions play major roles in the evaluation of these λmagic, hence facilitating choosing circular polarization of lasers in the experiments. Moreover, the actual clock transitions in these ions are carried out among the hyperfine levels. The λmagic values in these hyperfine transitions are estimated and found to be different from λmagic for the atomic transitions due to different contributions coming from the vector and tensor parts of αd(ω). Importantly, we also present λmagic values that depend only on the scalar component of αd(ω) for their uses in a specially designed trap geometry for these ions so that they can be used unambiguously among any hyperfine levels of the atomic states of the clock transitions. We also present αd(ω) values explicitly at 1064 nm for the atomic states associated with the clock transitions, which may be useful for creating high-field-seeking traps for the above ions using the Nd:YAG laser. The tune-out wavelengths at which the states would be free from the Stark shifts are also presented. Accurate values of the electric dipole matrix elements required for these studies are given and trends of electron correlation effects in determining them are also highlighted. [ABSTRACT FROM AUTHOR]

The article focuses on research published online on November 3, 2016 in "Cell Chemical Biology" concerning advances in electron microscopy in which different metal ions are sequentially layered on top of a sample which interacts with the electron beam and yields signature wave shapes that can be converted into colors.

The article focuses on the move of the U.S. Food and Drug Administration (FDA) to issue orders for postmarket surveillance examinations from numerous orthopaedic device manufacturers of metal-on-metal (MOM) total hip arthroplasty (THA) implant systems. It notes that the said agency aims to gain information on metal ion concentrations and their effects on long-term results for patients with THA. Moreover, it mentions that the studies will last for at least three years.