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The article presents adiabatic potential energy curves of the ground and excited electronic states for the diatomic NaK molecule. The calculations were made using the ab initio computational methods to include electron correlation. The studied molecule was calculated as the effective two-electron problem, in which only the valence electrons of the molecule are explicitly taken into account. The remaining electrons with atomic nuclei are described with appropriate, energy-consistent relativistic pseudopotentials. Additionally, a bespoke basis set, generated and optimised for both ground and excited electronic states of the NaK system was developed. The spectroscopic parameters of the calculated potential energy curves were determined and compared with the available experimental and theoretical results. The compliance of the obtained results, despite slight differences, is very satisfactory. [ABSTRACT FROM AUTHOR]

Introduction: New challenges in dialysis care delivery confront caregivers with the rise in dialysis numbers. There are significant lacunae in the knowledge and efficient application of dialysis therapy in the absence of a dialysis registry. This multicentric study was conducted by the Nephrology Association of Karnataka to systematically study patient demographics and dialysis characteristics in Karnataka state, India, as a basis for a statewide dialysis registry. Material and Methods: Data were collected from the consenting dialysis centers after institutional ethics board clearances. Residents of Karnataka state, who were confirmed prevalent patients with end-stage renal disease, on either maintenance hemodialysis (HD) or peritoneal dialysis were included. Demographic data of patients and details of dialysis as well as dialysis facilities were collected on an online platform. Statistical analysis was done using SPSS software Version 16. Results: Thirty-two centers contributed to the data of 2,050 patients (males 70.3%, mean age 53.49 ± 14.09 years). Most patients were on HD (95.3%). Diabetes was the commonest cause of chronic kidney disease. About 72% of patients had temporary venous catheters as initial vascular access. In all, 1,156 patients (59.9%) were on thrice weekly HD. Around 65% of the centers were in private hospitals. The majority (90%) of the centers reused dialyzers, 56% reprocessed dialyzers mechanically, and 66% tested viral serology quarterly. Conclusions: This study was one of the initial attempts to capture dialysis data across Karnataka, and it offers useful insight into the existing dialysis demographics and care delivery. Participation of more centers and continued effort to form a dialysis registry for deriving meaningful clinico-epidemiological insight are desirable. [ABSTRACT FROM AUTHOR]

Mitochondrial introgression is known as one of the major causes of misleading relationships and mito-nuclear discordance in phylogenetic analyses. It appears to be a quite widespread phenomenon in different animal taxa, with most records among vertebrates and insects. So far, in brachyuran crabs such reports of introgression are relatively infrequent. In the present study, we report such a case occurring among Central and West African mangrove crabs, using a multi-locus genetic approach. Our mito-nuclear phylogenetic comparison suggests a mitochondrial introgression between two sesarmid crab species. Based on our preliminary evidence, it seems that the mitochondrial genome of Guinearma alberti has been transferred to representatives of G. huzardi through introgression. These two species have a wide sympatric distribution along the West African coast and are considered to be congeneric based on their relatively close phylogenetic relationship. [ABSTRACT FROM AUTHOR]

Fagineura Vikberg & Zinovjev, 2000 is recorded from China for the first time. Two species of Fagineura are described as new, F. flactoserrula sp. n. and F. xanthosoma sp. n. A key to the species of Fagineura worldwide is provided, now including four species. In addition, a simple phylogenetic analysis of Fagineura species is provided, based on sequences of the COI and NaK genes. [ABSTRACT FROM AUTHOR]

Diffusion Monte Carlo (DMC) and Reptation Monte Carlo (RMC) methods, have been applied to study some properties of the NaK molecule. Hartree-Fock (HF), Density Functional (DFT) and single and double configuration interaction (SDCI) wavefunctions with a valence quadruple zeta atomic natural orbital (VQZ/ANO) basis set were used as trial wavefunctions. Values for the potential energy curve, dissociation energy and dipole moment were calculated for all methods and compared with experimental results and previous theoretical derivations. Quantum Monte Carlo (QMC) calculations were shown to be useful methods to recover correlation in NaK, essential to obtain a reasonable description of the molecule. The equilibrium distance yield a value close to the experimental one. The dissociation energy, however, is not so good, and the minimum error is about 4% of the experimental value, except when a coupled-clusters method is used. In this case, a conventional CCSD(T) calculation with an extended aug-pc-4 basis set gives a much better agreement to experiment. However, neither the CCSD(T) nor other MO and DFT methods are able to reproduce correctly the large dipole moment of this molecule. Even DMC methods with a simple HF trial wavefunction are able to give a better agreement to experiment, although they have a larger error bar. [ABSTRACT FROM AUTHOR]

Experiments were performed with Test-section of LLCB TBM on NaK. Test-section made of stainless steel (SS) included inlet pipe, inlet collector of rectangular cross section, two rows of parallel poloidal (vertical) ducts and outer collector with outlet pipe. Numerical simulation has been carried out using MHD module of FLUENT. Various flow properties like side wall electric potential distribution, pressure and velocity distribution has been compared with measured values. [ABSTRACT FROM AUTHOR]

• Corrosion morphologies of RAFM steel F82H and 316 L austenitic steel in liquid alkali metals Li, Na and NaK were compared. • Significant temperature dependence of corrosion in liquid alkali metals was clarified. • Li diffusion into the steel matrix was analyzed by TOF-SIMS. • Oxides formed on F82H specimens in liquid Na and NaK were identified. Liquid metals Li, Na and NaK are the candidate heat transfer mediums which are installed in the irradiation capsule of advanced fusion neutron source. The compatibility issue of F82H and 316L in the candidate heat transfer mediums was studied by means of the corrosion tests at the temperature up to 823 K. The depletion of Cr, C and Fe from the steel was caused in liquid Li. The Li diffusion into the steel matrix was analyzed by TOF-SIMS. The corrosion in liquid Na was caused by the Na diffusion into the steel matrix and the surface oxidation. The corrosion in NaK was similar with that in liquid Na. [ABSTRACT FROM AUTHOR]

Cost and volume savings are some of the advantages offered by the use of latent heat thermal energy storage (TES). Metallic phase change materials (PCMs) have high thermal conductivity, which relate to high charging and discharging rates in TES system, and can operate at temperatures exceeding 560°C. In the study, a eutectic aluminium-silicon alloy, AlSi12, is identified as a good potential PCM. AlSi12 has a melting temperature of 577°C, which is above the working temperature of regular heat transfer fluids (HTFs). The eutectic sodium-potassium alloy (NaK) is identified as an ideal HTF in a storage system that uses metallic PCMs. A concept is presented that integrates the TES-unit and steam generator into one unit. As NaK is highly reactive with water, the inherently high thermal conductivity of AlSi12 is utilized in order to create a safe concept. As a proof of concept, a steam power-generating cycle was considered that is especially suited for a TES using AlSi12 as PCM. The plant was designed to deliver 100 MW with 15 h of storage. Thermodynamic and heat transfer analysis showed that the concept is viable. The analysis indicated that the cost of the AlSi12 storage material is 14.7 US$per kWh of thermal energy storage. [ABSTRACT FROM AUTHOR]

The genus Hoplitis ( Megachilidae: Osmiini) comprises about 360 described species and occurs on all continents except Australia, South America, and Antarctica. Using five genes, we inferred the phylogeny of Hoplitis including 23 out of the 27 currently recognized subgenera, applying both Bayesian and maximum likelihood methods. Compared to the current morphology-based classification, our phylogeny resulted in three classificatory changes: first, the subgenera Alcidamea, Cyrtosmia, Dasyosmia, Megalosmia, Monumetha, and Prionohoplitis are merged into one large subgenus Alcidamea Cresson, 1864, comb. nov.; second, the subgenera Annosmia, Bytinskia, Coloplitis, and Hoplitis are merged into one large subgenus Hoplitis Klug, 1807, comb. nov.; third, the subgenera Acrosmia, Hoplitina, Penteriades, and Proteriades are merged into one large subgenus Proteriades Titus, 1904, comb. nov. We provide evidence that the genus Hoplitis has a Palaearctic origin and that colonization events to southern Africa and to the Nearctic, as well as recolonization events from the Nearctic to the Palaearctic occurred. The species of the genus Hoplitis exhibit an extraordinary diversity in nesting behaviour, comprising both below and above ground nesting. Parsimony mapping revealed that ground nesting in excavated burrows is the ancestral state amongst Hoplitis bees. We hypothesize that nesting biology strongly affected both range expansion and long-distance dispersal in Hoplitis. © 2012 The Linnean Society of London [ABSTRACT FROM AUTHOR]

Abstract: The relative transition dipole moment function M(R) for the 4 3Σ+ → a 3Σ+ electronic transition in the sodium–potassium molecule (NaK) has been determined by fitting experimental bound–free and bound–bound emission spectra. The fit is performed using a modified version of the BCONT computer program, which was originally developed by Le Roy. Spectra previously measured in this laboratory from low-lying ro-vibrational levels of the 4 3Σ+ state and new spectra from high-lying levels are included in the fit. A slight adjustment to the inner, repulsive wall of the 4 3Σ+ potential leads to an improved form for that curve. The fitted M(R), when appropriately scaled, agrees very well with recent ab initio calculations of Magnier et al. [Copyright &y& Elsevier]

Abstract: Spin–orbit coupling constants calculated for several excited states of the NaK molecule are used to interpret recent experiments. The theoretical results, which provide coupling constants as a function of internuclear separation , were convoluted with vibrational wavefunctions in order to determine vibrational-state-dependent spectroscopic constants that could be compared with recent measurements for the state. Sharp structure in the experimental data could be attributed to rapid changes in the adiabatic spin–orbit coupling near an avoided crossing. [Copyright &y& Elsevier]

Abstract: Protein trafficking is highly regulated in polarized cells. During development, how the trafficking of cell junctional proteins is regulated for cell specialization is largely unknown. In the maturation of Drosophila larval salivary glands (SGs), the Dlg protein is essential for septate junction formation. We show that Dlg was enriched in the apical membrane domain of proximal cells and localized basolaterally in distal mature cells. The transition of Dlg distribution was disrupted in nak mutants. Nak associated with the AP-2 subunit α-Ada and the AP-1 subunit AP-1γ. In SG cells disrupting AP-1 and AP-2 activities, Dlg was enriched in the apical membrane. Therefore, Nak regulates the transition of Dlg distribution likely through endocytosis of Dlg from the apical membrane domain and transcytosis of Dlg to the basolateral membrane domain during the maturation of SGs development. [Copyright &y& Elsevier]

Abstract: Two-colour polarisation labelling experiments measuring the D–X system of NaK have furnished observations of the D 1Π state of NaK up to v″=42. The last observed level is located 7cm−1 below the Na(3p 2P3/2)+K(4s) atomic asymptote, 22247.15cm−1 above the minimum of the electronic ground state, clearly indicating the dissociation products of this state. The vibrational progressions all exhibit irregular intervals, predominantly because of strong interactions with the nearby d 3Π state, which also dissociates to Na(3p)+K(4s) atoms. The polarisation data have been combined with some resolved fluorescence D–X transitions, and analysed by fitting to spectroscopic parameters and to an analytical potential curve. A full deperturbation treatment has not been attempted, but a ‘robust’ weighting scheme has been used to reduce the influence of levels that cannot be properly represented by a single channel model. Parameters determined in a fit to a potential curve include T e =20090.18±0.02cm−1, well depth 2157.0±0.3cm−1, R e =4.1547±0.0002Å, with an unweighted root mean square error of 0.12cm−1 for 959 data. [Copyright &y& Elsevier]

Abstract: The mutual dependencies of characteristic quantities for an isotope selective photoionization, namely optimization efficiency, target state population, and wave packet dephasing are presented for the NaK dimer. A pre-optimized pulse shape obtained from the maximization of the isotopomer ratio 23Na39K/23Na41K for the first excited electronic state serves as an initial guess for the subsequent optimization. For the ionization it provides almost vanishing population of the heavier ionic isotopomer and an ionic isotopomer ratio which is significant higher than the findings obtained from former investigations. The wave packet motions on the first excited state of the neutral molecule are in phase for both isotopomers. The optimization procedure, i.e. the simultaneous maximization of the 23Na39K+ photoionization yield and the minimization of the 23Na41K+ photoionization yield for the electronic ground state is based on optimal control theory and leads to a rise of ionic ground state population for both isotopomers related to a significant wave packet dephasing. Upon optimization the isotopomer ratio of the yields falls due to incidental resonances of vibronic transitions. The interplay of the observables are discussed and compared with the values obtained from an optimization which was started from a pure Gaussian pulse shape. [Copyright &y& Elsevier]

Obtaining ultracold samples of dipolar molecules is a current challenge which requires an accurate knowledge of their electronic properties to guide the ongoing experiments. In this paper, we calculate permanent dipole moments and transition dipole moments for excited states for alkali dimers NaK, NaRb and NaCs using a standard quantum chemistry approach based on pseudopotentials for atomic core representation, Gaussian basis sets, and effective terms for core polarization effects. We provide an extensive set of data concerning transitions among the first seven molecular states of each symmetry 1Σ+, 3Σ+, 1Π, 3Π. The accuracy of our results is generally improved compared to previous similar calculations on NaK, while they are found to be in good agreement with the few NaRb states calculated with other methods. Results for NaCs transition dipole moments are given here for the first time. [ABSTRACT FROM AUTHOR]

Abstract: We have studied the mutually perturbing 33Π Ω=0(v =32, J =19)∼31Π Ω=1(v =6, J =19) levels of NaK that are coupled together by the spin–orbit interaction. We note that this coupling is nominally forbidden by the ΔΩ =0 selection rule for spin–orbit perturbations. However 33Π levels labeled by different values of Ω are mixed by rotational coupling; i.e. the 33Π Ω levels are best described by a coupling scheme intermediate between Hund’s cases (a) and (b). Thus the 31Π Ω=1 level couples to the 33Π Ω=0 level via the small admixture of 33Π Ω=1 character in the latter. The 33Π Ω=0(v =32, J =19)∼31Π Ω=1(v =6, J =19) f symmetry pair is of particular interest since it appears to be very close to a 50–50 mixture of triplet and singlet character, and the splitting between these levels provides a direct measure of the 33Π∼31Π spin–orbit coupling constant. On the other hand, excitation spectra of the 33Π Ω=0(v =32, J =19)∼31Π Ω=1(v =6, J =19) e symmetry pair through the mixed “window” levels 1(b)3Π Ω=0(v =17, J =18,20)∼2(A)1Σ+(v =18, J =18,20) display dramatic quantum interference effects associated with “singlet” and “triplet” excitation channels. Almost complete cancellation for populating one or the other of the two upper states is observed for excitation from the predominantly triplet members of the window level pairs. [Copyright &y& Elsevier]

Abstract: The effects of sonochemical treatment of a NaK eutectic mixture as catalyst on the side-chain alkenylation of o-xylene with 1,3-butadiene were studied. The parameters studied include ultrasound frequency, insonation time, sonication power as well as the reaction temperature. In addition, the effect of N,N,N′,N′-tetramethylethylenediamine (TMEDA) on the reaction was also studied. The results showed that sonochemical treatment of this NaK eutectic mixture catalyst resulted in excellent conversion (up to 83.16%) under mild conditions. The introduction of TMEDA further increased the conversion to 89.4%. [Copyright &y& Elsevier]

Abstract: We have recorded electronic spectra of some diatomic species (I2, K2, and NaK), to illustrate the potential power of the combination of two high resolution techniques: intra-cavity laser induced fluorescence (ICLIF) and Fourier transform (FT) spectroscopy. Active and passive optical cavities have been used, working with visible continuous wave (cw) laser sources. The active cavity is a modified commercial ring dye laser, allowing for a sample up to 25cm in length. Dispersed fluorescence spectra recorded on a Bomem Fourier transform spectrometer showed a signal enhancement of about 10 when a molecular source was placed within the resonator. The system was tested with a heatpipe source, producing alkali metal vapour at about 300°C. These experiments illustrate enhanced cascade excitation mechanisms in K2; the highest vibrational levels of the electronic ground state of K2 can be observed with surprising ease. The increase in available power within the cavity has also led to the observation of fluorescence in NaK excited by a two-photon transition (Q (66) 61Σ+ ← X 1Σ+ transition). Spatial limitations have driven us to build a more versatile ring cavity able to accommodate larger sources. This broad-band (590–650nm) build-up cavity is locked by a Hänsch–Couillaud servo-loop to an input laser of (instantaneous) bandwidth ∼1MHz. Power enhancement factors of around 30 have been obtained with a 2.6% input coupler. The performance of the build-up cavity has been tested by recording FT spectra of intra-cavity laser induced fluorescence of iodine. The technique clearly has useful applications for weakly absorbing species, or for those whose electronic states are inaccessible to single-photon absorption techniques. This paper describes the arrangement we have used, highlighting some of the advantages and describing some of the particular difficulties we have encountered. [Copyright &y& Elsevier]

Abstract: The liquid lead-bismuth eutectic (Pbood compatibility with water, which is different from sodium. It is expected that the Pbbe used as a coolant of the deep sea fast reactor (DSFR). Physics analysis of the Pb small reactor cores with and without inner control rods performed using the computer program of a neutronics code system (SRAC95) shows that Pbtable for the coolant of small reactors as well as NaK. [Copyright &y& Elsevier]

Background and Objectives Anti-Naka, a platelet-specific antibody, occasionally causes platelet-transfusion refractoriness (PTR) together with human leucocyte antigen (HLA) antibodies. Anti-Naka usually appears after frequent platelet transfusions or pregnancy. We report the first case of PTR caused by anti-Naka alone. Materials and Methods A 19-year-old male patient with testicular tumour showed PTR when receiving his first transfusion of platelets. Screening for platelet antigens and platelet antibodies revealed that he had type I CD36 (Naka) deficiency and that anti-Naka, but not anti-HLA, was present before he received his first transfusion. Results The transfusion of Naka-negative, but HLA non-selected, platelets was effective in raising the platelet count. Conclusion Clinically significant Naka antibody was present as naturally occurring antibody in a platelet glycoprotein IV (CD36)-negative non-transfused male patient. [ABSTRACT FROM AUTHOR]