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Recent studies have revealed a surprising diversity of sex chromosomes in vertebrates. However, the detailed mechanism of their turnover is still elusive. To understand this process, it is necessary to compare closely related species in terms of sex-determining genes and the chromosomes harboring them. Here, we explored the genusTakifugu, in which one strong candidate sex-determining gene,Amhr2, has been identified. To trace the processes involved in transitions in the sex determination system in this genus, we studied 12 species and found that while theAmhr2locus likely determines sex in the majority ofTakifuguspecies, three species have acquired sex-determining loci at different chromosomal locations. Nevertheless, the generation of genome assemblies for the three species revealed that they share a portion of the male-specific supergene that contains a candidate sex-determining gene,GsdfY, along with genes that potentially play a role in male fitness. The shared supergene span approximately 100 kb and are flanked by two duplicated regions characterized by CACTA transposable elements. These results suggest that the shared supergene has taken over the role of sex-determining locus fromAmhr2in lineages leading to the three species, and repeated translocations of the supergene underlie the turnover of sex chromosomes in these lineages. These findings highlight the underestimated role of a mobile supergene in the turnover of sex chromosomes in vertebrates.SignificanceAlthough turnover of sex chromosomes is very common in many vertebrate lineages, the transition process is still elusive. We studied the sex-determining region (SDR) of 12 congeneric fish species. We found that while nine species retained their ancestral SDR, three species had acquired derived SDRs. Although the derived SDRs resided in three different chromosomes, they harbored a shared supergene flanked by two putative transposable elements. The results highlight the underestimated role of a mobile supergene in turnover of sex chromosomes in vertebrates.

We report 75As NMR experiments in heavily electron-doped LaFePnO0.75H0.25 (Pn=As1−x Sb x and As1−x′ P x′ ) compounds with the maximum T c max ( ∼ 33.1 K ) , and compare with the previous results in lightly electron-doped LaFePn(O,F) compounds. The Tc of this series can be sensitively controlled by the pnictogen height (hPn ) through the substitution at Pn site, and the electron doping level through the substitution at the O site with H or F. In heavily electron-doped LaFePnO(La1111) compounds, we found that spin fluctuations at low-energies were moderately suppressed upon cooling in the Sb-substituted high Tc compounds with high hPn (x ≥ 0), although they are completely suppressed in P-substituted non-superconducting compounds (x′ ≥ 0.2) with lower hPn . This feature is largely different from that in the lightly doped La1111 compounds with the well-nested Fermi surfaces, where the spin fluctuations are critically enhanced upon cooling. Here, we present the characteristics of spin fluctuations over wide doping region of La1111-based compounds, and discuss the relationship with the superconductivity.

Rare-earth intermetallic compounds exhibit rich phenomena induced by the interplay between localized $f$ orbitals and conduction electrons. However, since the energy scale of the crystal-electric-field splitting is only a few millielectronvolts, the nature of the mobile electrons accompanied by collective crystal-electric-field excitations has not been unveiled. Here, we examine the low-energy electronic structures of CeSb through the anomalous magnetostructural transitions below the N$\'{e}$el temperature, $\sim$17 K, termed the 'devil's staircase', using laser angle-resolved photoemission, Raman and neutron scattering spectroscopies. We report another type of electron-boson coupling between mobile electrons and quadrupole crystal-electric-field excitations of the 4$f$ orbitals, which renormalizes the Sb 5$p$ band prominently, yielding a kink at a very low energy ($\sim$7 meV). This coupling strength is strong and exhibits anomalous step-like enhancement during the devil's staircase transition, unveiling a new type of quasiparticle, named the 'multipole polaron', comprising a mobile electron dressed with a cloud of the quadrupole crystal-electric-field polarization., Comment: 21 pages, 4 figures

Rare-earth intermetallic compounds exhibit rich phenomena induced by the interplay between localized f orbitals and conduction electrons. However, since the energy scale of the crystal-electric-field splitting is only a few millielectronvolts, the nature of the mobile electrons accompanied by collective crystal-electric-field excitations has not been unveiled. Here, we examine the low-energy electronic structures of CeSb through the anomalous magnetostructural transitions below the Néel temperature, ~17 K, termed the 'devil's staircase', using laser angle-resolved photoemission, Raman and neutron scattering spectroscopies. We report another type of electron-boson coupling between mobile electrons and quadrupole crystal-electric-field excitations of the 4f orbitals, which renormalizes the Sb 5p band prominently, yielding a kink at a very low energy (~7 meV). This coupling strength is strong and exhibits anomalous step-like enhancement during the devil's staircase transition, unveiling a new type of quasiparticle, named the 'multipole polaron', comprising a mobile electron dressed with a cloud of the quadrupole crystal-electric-field polarization.

We present extractions of the nucleon nonsinglet moments utilizing new precision data on the deuteron F_{2} structure function at large Bjorken-x determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world datasets on the proton and deuteron at lower x measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the x range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high x data. Moreover, recent exciting developments in lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach that first calculates the quark distributions directly before determining moments.

Gut microbiome development affects infant health and postnatal physiology. The gut microbe assemblages of preterm infants have been reported to be different from that of healthy term infants. However, the patterns of ecosystem development and inter-individual differences remain poorly understood. We investigated hospitalised preterm infant gut microbiota development using 16S rRNA gene amplicons and the metabolic profiles of 268 stool samples obtained from 17 intensive care and 42 term infants to elucidate the dynamics and equilibria of the developing microbiota. Infant gut microbiota were predominated by Gram-positive cocci, Enterobacteriaceae or Bifidobacteriaceae, which showed sequential transitions to Bifidobacteriaceae-dominated microbiota. In neonatal intensive care unit preterm infants (NICU preterm infants), Staphylococcaceae abundance was higher immediately after birth than in healthy term infants, and Bifidobacteriaceae colonisation tended to be delayed. No specific NICU-cared infant enterotype-like cluster was observed, suggesting that the constrained environment only affected the pace of transition, but not infant gut microbiota equilibrium. Moreover, infants with Bifidobacteriaceae-dominated microbiota showed higher acetate concentrations and lower pH, which have been associated with host health. Our data provides an in-depth understanding of gut microbiota development in NICU preterm infants and complements earlier studies. Understanding the patterns and inter-individual differences of the preterm infant gut ecosystem is the first step towards controlling the risk of diseases in premature infants by targeting intestinal microbiota.

The objective of the study was to investigate whether an infant formula supplemented with galacto-oligosaccharides (GOS; OM55N) was able to stimulate the growth of indigenous bifidobacteria and to establish microbiota similar to that of breastfed infants. A randomised, double-blind, placebo-controlled trial was performed using 35 healthy term infants (31-54 days of age; 42±6 days) to determine whether infant formula with 0.3 g/dl GOS (OM55N) stimulated the growth of bifidobacteria in the infants’ guts. At the trial onset and 2 weeks after, the infants’ faecal samples were examined for microbiota composition (bacterial abundance and α-diversity) and faecal characteristics. Among the 35 infants, 5 were withdrawn and 8 were excluded from the final evaluation before breaking the blinding since the indigenous bifidobacteria were not detected at the trial onset. After 2 weeks, the abundance of Bifidobacteriaceae was significantly increased in the GOS feeding group compared to the control (+11.6±24.1% vs -3.9±13.0%; P=0.043). The Shannon index, which accounts for both abundance and evenness of the present species, was significantly decreased with GOS supplementation (-0.1±0.4 vs +0.4±0.4; P=0.014). Faecal characteristics such as pH and organic acids were similar in both groups, with no statistical differences. No adverse side effects related to the formula consumption were reported. Although the concentration of GOS was relatively low, the infant formula with GOS increased the abundance of bifidobacteria and resulted in a reduced α-diversity of the microbiota.

We present extractions of the nucleon nonsinglet moments utilizing new precision data on the deuteron F_{2} structure function at large Bjorken-x determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world datasets on the proton and deuteron at lower x measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the x range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high x data. Moreover, recent exciting developments in lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach that first calculates the quark distributions directly before determining moments.

In this paper, we present an innovative CH4, δ13CH4, and C2H6 instrument based on cavity ring-down spectroscopy (CRDS). The design and performance of the analyzer is presented in detail. The instrument is capable of precision of less than 1 ‰ on δ13CH4 with 1 in. of averaging and about 0.1 ‰ in an hour. Using this instrument, we present a comprehensive approach to atmospheric methane emissions attribution. Field measurements were performed in the Uintah Basin (Utah, USA) in the winter of 2013, using a mobile lab equipped with the CRDS analyzer, a high-accuracy GPS, a sonic anemometer, and an onboard gas storage and playback system. With a small population and almost no other sources of methane and ethane other than oil and gas extraction activities, the Uintah Basin represents an ideal location to investigate and validate new measurement methods of atmospheric methane and ethane. We present the results of measurements of the individual fugitive emissions from 23 natural gas wells and six oil wells in the region. The δ13CH4 and C2H6 signatures that we observe are consistent with the signatures of the gases found in the wells. Furthermore, regional measurements of the atmospheric CH4, δ13CH4, and C2H6 signatures throughout the basin have been made, using continuous sampling into a 450 m long tube and laboratory reanalysis with the CRDS instrument. These measurements suggest that 85 ± 7 % of the total emissions in the basin are from natural gas production.

In this paper, we present an innovative CH4, δ13CH4, and C2H6 instrument based on cavity ring-down spectroscopy (CRDS). The design and performance of the analyzer is presented in detail. The instrument is capable of precision of less than 1 ‰ on δ13CH4 with 1 in. of averaging and about 0.1 ‰ in an hour. Using this instrument, we present a comprehensive approach to atmospheric methane emissions attribution. Field measurements were performed in the Uintah Basin (Utah, USA) in the winter of 2013, using a mobile lab equipped with the CRDS analyzer, a high-accuracy GPS, a sonic anemometer, and an onboard gas storage and playback system. With a small population and almost no other sources of methane and ethane other than oil and gas extraction activities, the Uintah Basin represents an ideal location to investigate and validate new measurement methods of atmospheric methane and ethane. We present the results of measurements of the individual fugitive emissions from 23 natural gas wells and six oil wells in the region. The δ13CH4 and C2H6 signatures that we observe are consistent with the signatures of the gases found in the wells. Furthermore, regional measurements of the atmospheric CH4, δ13CH4, and C2H6 signatures throughout the basin have been made, using continuous sampling into a 450 m long tube and laboratory reanalysis with the CRDS instrument. These measurements suggest that 85 ± 7 % of the total emissions in the basin are from natural gas production.

In contrast to the majority of allergic or hypersensitivity conditions, worldwide anaphylaxis epidemiological data remain sparse with low accuracy, which hampers comparable morbidity statistics. Data can differ widely depending on a number of variables. In the current document we reviewed the forms on which anaphylaxis has been defined and classified; and how it can affect epidemiological data. With regards to the methods used to capture morbidity statistics, we observed the impact of the anaphylaxis coding utilizing the World Health Organization's International Classification of Diseases. As an outcome and depending on the anaphylaxis definition, we extracted the cumulative incidence, which may not reflect the real number of new cases. The new ICD-11 anaphylaxis subsection developments and critical view of morbidity statistics data are discussed in order to reach new perspectives on anaphylaxis epidemiology. © 2018 The Author(s).

Martensitic transformation and magnetic properties were investigated for Ni43Co7Mn39Sn11 polycrystalline specimens obtained using the spark plasma sintering method. The microstructure of the specimen sintered at 1173 K for 15 min showed only a small number of pores, and the specimen’s ductility was significantly higher than that of alloys fabricated by conventional induction melting. The martensitic and magnetic properties of the sintered specimen were basically similar to those of conventional bulk alloys. The metamagnetic shape memory effect, i.e. magnetic field-induced shape recovery, was confirmed by the magnetic field of 8 T.

A family of hypersurface isolated singularities, called Reiffen’s examples, is considered in the context of holonomic D-modules. Algebraic local cohomology classes attached to Reiffen’s singularities and their annihilating differential operators are studied. The algebraic local cohomology solution space to the first-order holonomic D-module is determined explicitly. As an application, it is shown that the multiplicity of the holonomic D-module can be described in terms of classical invariants of singularities.

Recoil polarimetry was used to extract the ratio of the proton electromagnetic form factors, μ p G E p / G M p = 0.878 ± 0.064 (stat) ± 0.012 (sys) , at Q 2 = 1.13 ( GeV / c ) 2 from the reaction H 1 ( e → , e p → ) . This was an ancillary measurement in which the proton polarization was determined as part of a larger program utilizing a stand-alone polarimeter designed to measure μ n G E n / G M n . This measurement complements previous recoil polarimetry measurements of μ p G E p / G M p made at the Thomas Jefferson National Accelerator Facility.

Dynamical structures in the vicinity of Q = ( \pi , \hspace{0.167em} \pi ) of optimally-doped YBa2Cu3O6.9 were measured by means of an inelastic neutron scattering technique utilizing pulsed neutron source. Obtained incommensurability δ of energy transfer at E = 36 \hspace{0.167em} meV was found to be ∼0.1 [rlu] which is not the value to be expected from the formation of spin-charge stripes. In higher energy above resonance energy (42 meV), a ring structure centered at (π, π) was observed up to 54 meV. Combined with the low energy part of the dynamical structure, the obtained results provide a total picture of the dynamical aspects in the high-T c superconductor YBa2Cu3O6.9.

We measured the flux flow resistivity ρ f associated with a purely viscous motion of the vortices in high-quality MgB 2 by the microwave surface impedance. The flux flow resistivity exhibits unusual field dependence with strong enhancement at low fields, which is markedly different from that in conventional s-wave superconductors. A crossover field which separates two distinct flux flow regime with different slope of ρ f was observed in H ∥ ab -plane. The unusual H -dependence indicates that two very differently sized superconducting gaps in MgB 2 manifest themselves clearly in the vortex dynamics and nearly equally contribute to the energy dissipation.

Effect of grain boundaries on the magnetic field distributions in YBCO was studied by use of magneto-optical (MO) imaging technique. The grain boundary was artificially introduced with a multi-seeded melt-growth process. The current distribution in the sample was obtained from the MO image using an inversion scheme based on the inverse-matrix method. With this technique, we could obtain intergranular and intragranular critical current densities. Large depression of the intergranular critical current was observed in the sample with large misorientation angles.

We measured magnetization of Zn-substituted YBCO single crystals in the overdoped, optimally-doped, and underdoped regimes, and estimated critical current density ( J c ). The Zn-substitution less than 1% enhances the second peak of J c in overdoped regime, while it almost suppresses in underdoped regime. The optimized Zn-concentration changes as function of carrier concentration. Carrier-doping increases irreversibility field ( H irr ), while Zn-substitution decreases H irr at all doping levels. It implies that the point defect is not effective pinning center for higher H irr .

Lithium ion was successfully introduced into La{sub 1/3}NbO{sub 3} with an A-site-deficient perovskite-type structure. The crystal structure and transport properties of La{sub 1/3}Li{sub x}NbO{sub 3} were investigated as a function of Li content (x = 0-0.59). The lattice parameters of La{sub 1/3}Li{sub x}NbO{sub 3} with an orthorhombic cell were enlarged with increasing Li content for x {

A lattice Boltzmann method for two-phase immiscible fluids with large density differences is proposed. The difficulty in the treatment of large density difference is resolved by using the projection method. The method can be applied to simulate two-phase fluid flows with the density ratio up to 1000. To show the validity of the method, we apply the method to the simulations of capillary waves, binary droplet collisions, and bubble flows. In capillary waves, the angular frequencies of the oscillation of an ellipsoidal droplet are obtained in good agreement with theoretical ones. In the simulations of binary droplet collisions, coalescence collision and two different types of separating collisions, namely reflexive and stretching separations, can be simulated, and the boundaries of the three types of collisions are in good agreement with an available theoretical prediction. In the bubble flows, the effect of mobility on the coalescence of two rising bubbles is investigated. The behavior of many bubbles in a square duct is also simulated.

We discuss Scanning Tunneling Microscopy and Spectroscopy (STM/S) measurements at very low temperatures in single crystals of the non magnetic borocarbide superconductors RNi 2 B 2 C ( R = Y , Lu , T c=15.5 and 16.5 K) and in MgB 2. The tunneling spectra in some regions of the surface show a clear reduction of the anisotropy of the superconducting gap.

The ratio of the electric to the magnetic form factor of the neutron, \(g \equiv G_{En}/G_{Mn}\), was measured via recoil polarimetry (R.G. Arnold, C.E. Carlson, F. Gross, Phys. Rev. C 23, 363 (1981)) from the quasielastic 2H\((\mathop{e}\limits^{\scriptstyle\to},e' \mathop{n}\limits^{\scriptstyle\to} )\)1H reaction at three values of Q2 (viz, 0.45, 1.15, and 1.47 (GeV/c)2) in Hall C of the Thomas Jefferson National Accelerator Facility. The data reveal that GEn continues to follow the Galster parameterization up to Q2 = 1.15 (GeV/c)2 and rises above the Galster parameterization at Q2 = 1.47 (GeV/c)2.

Angiosarcoma is a rare and aggressive type of sarcoma, and primary angiosarcoma of the ovary is extremely rare. We report the case of a 29-year-old woman who was diagnosed with ovarian angiosarcoma and possible bone metastases. We treated this patient with a gemcitabine-based regimen as postoperative adjuvant chemotherapy, after which she achieved at least 7 years of progression-free survival, an extremely long duration given the aggressive features of this tumour. We retrospectively performed immunohistochemical analyses and fluorescence in situ hybridization to make a pathology diagnosis and to investigate the tumour features. MYC amplification and c-Myc protein overexpression were positively detected. It might be possible to correlate the effectiveness of the gemcitabine-based chemotherapeutic regimen with MYC gene amplification and c-Myc protein overexpression.

The A(e,e{prime}K{sup +})YX reaction on H, D, {sup 3}He, and {sup 4}He was investigated in Hall C at CEBAF. Data were obtained for Q{sup 2} {approx} 0.35 and 0.5 GeV{sup 2} at 3.245 GeV. The missing mass spectra for both H and D are fitted with Monte-Carlo simulations incorporating peaks corresponding to {Lambda} production on the proton and {Sigma} production on both the proton and neutron. For D, the cross section ratio {Sigma}{sup 0}/{Sigma}{sup {minus}} {approx} 2, and excess yield close to the thresholds for {Lambda} and {Sigma} production can be attributed to final-state interactions that are compared to the data. The analysis of the data for the He targets is in a more preliminary state with broader quasi-free peaks resulting from the higher Fermi momenta. Evidence for bound {Lambda}-hypernuclear states is seen and other structure may be present.

High- T c superconducting oxides with nominal compositions of HgBa 2 Cu 1− x M x O 4+ δ (M=Fe, Co, Ni, Zn and Mg, x =0–0.03) were prepared, and crystal structure and substitution effects on superconducting properties were studied using X-ray powder diffraction, susceptibility and resistivity. Almost all single-phase samples were obtained for M=Fe, Co, Zn and Mg, while impurities such as Ni 3 Ba 3 O 8 were detected for M=Ni. A significant decrease in T c and an increase in lattice parameter a for the samples with Zn and Mg indicated that these metals were successfully substituted for Cu. On the other hand, there was no remarkable change in T c for the sample with Fe and Co, which suggests a possibility of substitution for Hg. Zn- and Mg-substitution effects on superconductivity were discussed from the viewpoint of structural change, in comparison with the cases of La 2− x Sr x CuO 4 and YBa 2 Cu 3 O 6+ δ .

A detailed investigation of the basic hyperon-nucleon interactions in nuclei is one of the aims of Experiment 91-016, approved with high priority at CEBAF, to study the electroproduction of kaons on targets of deuterium, {sup 3}He, and {sup 4}He. Inasmuch as both the electron and K{sup +} are particles that interact relatively weakly with nucleons, electroproduction of light hypernuclei provides a low-distortion method for investigating the fundamental interactions between nucleons, {Alpha}`s, and {Epsilon}`s in few-body systems. In particular, the (e,e`K{sup +}) reactions on cryogenic targets of D, {sup 3}He, and {sup 4}He will be studied at incident electron energies near 3 GeV with coincident detection of the emergent e and K{sup +} in the HMS and SOS magnetic spectrometers in Hall C. Construction of the He target, operating at {approximately}10 atm, {approximately}50 K and capable of dissipating {approximately}30 W, is expected to be complete prior to commencement of production runs in Hall C. The first data runs for E91-016, expected to begin late in FY 1995, will also be the basis for a doctoral thesis at Hampton University. In addition to providing new information on the phases of hyperon-nucleon interactions, measurements of cross sections for hypernuclear formation, and interference phenomena,more » the data may provide evidence for the presence of bound {Epsilon}`s and strange di-baryonic states that are the subject of considerable theoretical discussion.« less

Here we report use of angle scanning photoemission spectroscopy using polarized synchrotron light to explore the Fermi surface topology of Bi 2 Sr 2 CaCu 2 O 8± δ superconductors. The measurements were made in different experimental geometry to take care of the polarization dependence of photoemission transition probability (matrix element effect) and discriminate the true features along the high symmetry directions. We find an asymmetric suppression of spectral weight around M(π,0) point indicating coupling of the itinerant carriers with an incommensurate charge density wave (ICDW) i.e. stripes, involving modulation of the orbital momentum.

We systematically synthesized (Hg,M)-1222 cuprates, (Hg,M)Sr 2 (Ln,Ce) 2 Cu 2 O z under 2 GPa at 1100°C. Single or nearly single-phase compounds are successfully obtained for M = Ti, V, Cr, Mo, W and Re, and for Ln = Sm-Er. The structure of these compounds belongs to the same family of 1222 phase and is derived from that of (Hg,M)Sr 2 (Ca,Ln)Cu 2 O z by replacing the single (Ca,Ln) layer with a double fluorite (Ln,Ce) 2 O 2 layer. The (Hg 0.75 W 0.25 )Sr 2 (Gd 1.5 Ce 0.5 )Cu 2 O z compound crystallizes in a tetragonal lattice with cell parameters a = 3.832, c = 29.150 A. All synthesized samples, except for the compound with Cr, show bulk superconductivity with large Meissner volume fractions. T c was found to increase with increasing valence of the cation M and with decreasing ionic radius of Ln. The maximum T c of 75 K is obtained for (Hg 0.75 W 0.25 )Sr 2 (Gd 1.5 Ce 0.5 )Cu 2 O z .

Nearly single-phase superconducting (Tl 1− x Hg x ) 2 Sr 2 Ca 2 Cu 3 O y samples were prepared by the high-pressure technique. As-prepared samples with x =0.35 and 0.65, with optimally nominal oxygen contents, were overdoped and show T c of 103 and 80 K, respectively. Reducing treatments in Ar/H 2 were found to be effective in increasing T c up to 116 and 118 K for x =0.35 and 0.65, respectively. The increase in T c is also accompanied by a small weight loss and an increase in the room temperature c -axis length, with both phenomena resulting from oxygen loss. The crystal structure of the sample with x =0.35 was determined by X-ray Rietveld refinements. This crystal belongs to a tetragonal system and has a space group of I 4/ mmm with a =3.8130(5) and c=34.7230(4) A . According to the present refinement, the Tl site must be partially occupied by a lighter element, whereas the Ca site is occupied by a heavier one and the O(4) atom must shift from its ideal position 4e site (1/2,1/2, z ) to the 16m site ( x , x , z ).

We have synthesized and studied a series of high- T c superconductors (HTSC) HgBa 2 Cu 1− x Zn x O 4+ δ ( x =0, 0.01, 0.02 and 0.03) from underdoping to overdoping state. Lattice parameter a increased with increasing nominal composition of Zn ( x ), similar to Zn-substituted (La,Sr) 2 CuO 4 and YBa 2 Cu 3 O 6+ δ , indicating a replacement of Zn for Cu. As x increased, T c determined by susceptibility and resistivity decreased for all doping levels.

The adenosine triphosphate (ATP) content of keloids and scars resected from patients was demonstrated by high-performance liquid chromatography. The surface color of hypertrophic scars was red or pink and that of atrophic scars was white. The ATP content of red scars was (in mmol/g protein) 1.06 +/- 0.14, of pink scars 0.12 +/- 0.02, of white atrophic scars 0.19 +/- 0.06, and of keloids 1.06 +/- 0.19. The longer the elapsed time after the trauma, the lower the level of ATP in scar tissues (correlation coefficient = -0.506; p = 0.005 by Spearman's rank correlation). However, ATP levels in keloids were still high 10 years after the injury. Fibroblasts and fibrocytes in keloids and scars were counted in histologic preparations stained with hematoxylin and eosin. The average number of fibroblasts in a definite area (56 x 10(-4) mm at a magnification of x400) was 4.8 in keloids, 5.1 in red scars, 2.4 in pink scars, and 1.3 in white atrophic scars. The number of fibrocytes in the same area was 0.4 in keloids, 0.4 in red scars, 2.3 in pink scars, and 1.3 in white atrophic scars. These results indicate that keloids and red hypertrophic scars have higher ATP levels and contain more fibroblasts than pink or white scars, and they also suggest that the levels of ATP and the number of fibroblasts decrease when red hypertrophic scars change into atrophic scars. In keloids, ATP and fibroblasts seem to remain at high levels for a long time.

Partial substitutions of La for alkaline-earth elements of perovskite-type APbO{sub 3{minus}{delta}} (A = Ba, Sr, and Ca) were studied in order to examine carrier doping effects on the APbO{sub 3{minus}{delta}} system. The solubility limit of La was found to be about 10% for every alkaline-earth element. The temperature dependencies of electrical resistivity and the Seebeck coefficient for A{sub 0.9}La{sub 0.1}PbO{sub 3{minus}{delta}} samples indicated that they were metallic conductors, irrespective of the ionic size of the alkaline-earth elements. This is in good contrast with the resistivity of APbO{sub 3{minus}{delta}}, which is strongly influenced by the ionic size of A, via the distortion of PbO{sub 6} octahedra. The Seebeck coefficients for the A{sub 1{minus}x}La{sub x}PbO{sub 3{minus}{delta}} (x = 0 and 0.1) samples were negative, and absolute values were reduced by the La substitution, which implies that electron carriers were introduced into the conduction band. Superconductivity was not observed in these compounds down to 1.8 K, although the carrier density expected, based on the Seebeck coefficient, was comparable to the value for the superconducting BaPb{sub 1{minus}x}Bi{sub x}O{sub 3}.

We have studied momentum distribution of photoemission intensity around the Fermi surface of Bi 2 Sr 2 CaCu 2 O 8+ δ (Bi2212) high T c superconductor by angle-resolved photoemission. The line shape of the energy distribution curves show a spectral function A ( k , ω ) expected for a non-Fermi liquid behaviour. The Fermi surface contour in the `even symmetry' reveals the suppression of spectral weight due to coupling with joint incommensurate charge density wave (ICDW) at q (−0.4 π ,0.4 π ) in the diagonal direction and the spin density wave (SDW) at G ( π , π ). Additional spectral weight is found at (0.6 π ,0.6 π ) due to scattering of electrons with SDW at optimum doping as revealed by constant energy contour in `odd symmetry'.

Anisotropic optical conductivity spectra have been investigated for the hole-doped two-leg ladder system ${\mathrm{Sr}}_{14\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{Cu}}_{24}{\mathrm{O}}_{41}$. As in the case of the underdoped high- ${T}_{\mathrm{c}}$ cuprates, upon cooling a pseudogap opens in the spectrum for the transverse ( $a$-axis) polarization, and concurrently a peak develops in the far infrared region of the longitudinal ( $c$-axis) spectrum. A possible interpretation for these results is that the pseudogap signals a formation of hole pairs on the ladders and the peak might correspond to a pinned collective mode of a regular array of hole pairs.

We report measurements of the normal state c-axis magnetoresistance (MR) of untwinned single crystals of slightly overdoped YBa2Cu3O7−δ. An orbital contribution to the transverse MR, a signature of coherent c- axis motion, arises only from the component of the magnetic field perpendicular to the CuO chains. This result implies that the CuO chains are primarily responsible for coherent transport along the c-axis in YBa2Cu3O7−δand that those regions of the CuO2planes that do not involve the chains remain two-dimensional, even in the absence of a normal state gap.

We investigate the perturbed Lame equation with 1-zone potential and give an explicit description of the geometric phase that is contained in the leading term of the series of an asymptotic solution.