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The electronic structure of LaOFeAs, a parent compound of iron-arsenic superconductors, is studied by angleresolved photoemission spectroscopy. By examining its dependence on photon energy, polarization, sodium dosing and the counting of Fermi surface volume, both the bulk and the surface contributions are identified. We find that a bulk band moves toward high binding energies below structural transition, and shifts smoothly across the spin density wave transition by about 25 meV. Our data suggest the band reconstruction may play a crucial role in the spin density wave transition, and the structural transition is driven by the short range magnetic order. For the surface states, both the LaO-terminated and FeAs-terminated components are revealed. Certain small band shifts are verified for the FeAs-terminated surface states in the spin density wave state, which is a reflection of the bulk electronic structure reconstruction. Moreover, sharp quasiparticle peaks quickly rise at low temperatures, indicating of drastic reduction of the scattering rate. A kink structure in one of the surface band is shown to be possibly related to the electron-phonon interactions., 9 pages, 8 figures

Through a systematic high-resolution angle-resolved photoemission study of the iron pnictide compounds $(\text{Ba},\text{Sr}){\text{Fe}}_{2}{\text{As}}_{2}$, we show that the electronic structures of these compounds are significantly reconstructed across the spin density wave transition, which cannot be described by a simple folding scenario of conventional density wave ordering. Moreover, we find that LDA calculations with an incorporated suppressed magnetic moment of $0.5{\ensuremath{\mu}}_{\text{B}}$ can match well the details in the reconstructed electronic structure, suggesting that the nature of magnetism in the pnictides is more itinerant than local, while the origin of suppressed magnetic moment remains an important issue for future investigations.

We use high-resolution angle-resolved photoemission to study the electronic structure of the ${\text{BaFe}}_{2}{\text{As}}_{2}$ pnictides. We observe two electron bands and two hole bands near the X point, $(\ensuremath{\pi},\ensuremath{\pi})$ of the Brillouin zone, in the paramagnetic state for electron-doped $\text{Ba}{({\text{Co}}_{0.06}{\text{Fe}}_{0.94})}_{2}{\text{As}}_{2}$, undoped ${\text{BaFe}}_{2}{\text{As}}_{2}$, and hole-doped ${\text{Ba}}_{0.6}{\text{K}}_{0.4}{\text{Fe}}_{2}{\text{As}}_{2}$. Among these bands, only the electron bands cross the Fermi level, forming two electron pockets around X while the hole bands approach but never reach the Fermi level. We show that the band structure of the ${\text{BaFe}}_{2}{\text{As}}_{2}$ family matches reasonably well with the prediction of local-density approximation calculations after a momentum-dependent shift and renormalization. Our finding resolves a number of inconsistencies regarding the electronic structure of pnictides.

We report the first observation of the multilayer band splitting in the optimally doped trilayer cuprate Bi2Sr2Ca2Cu3O(10+δ) (Bi2223) by angle-resolved photoemission spectroscopy. The observed energy bands and Fermi surfaces are originated from the outer and inner CuO2 planes (OP and IP). The OP band is overdoped with a large d-wave gap around the node of Δ0∼43 meV while the IP is underdoped with an even large gap of Δ0∼60 meV. These energy gaps are much larger than those for the same doping level of the double-layer cuprates, which leads to the large Tc in Bi2223. We propose possible origins of the large superconducting gaps for the OP and IP: (1) minimal influence of out-of-plane disorder and a proximity effect and (2) interlayer tunneling of Cooper pairs between the OP and IP.

We report a comparison study of LaOFeP and LaOFeAs, two parent compounds of recently discovered iron-pnictide superconductors, using angle-resolved photoemission spectroscopy. Both systems exhibit some common features that are very different from well-studied cuprates. In addition, important differences have also been observed between these two ferrooxypnictides. For LaOFeP, quantitative agreement can be found between our photoemission data and the LDA band structure calculations, suggesting that a weak coupling approach based on an itinerant ground state may be more appropriate for understanding this new superconducting compound. In contrast, the agreement between LDA calculations and experiments in LaOFeAs is relatively poor, as highlighted by the unexpected Fermi surface topology around (pi,pi). Further investigations are required for a comprehensive understanding of the electronic structure of LaOFeAs and related compounds., 16 pages, 4 figures, for the special issue of Physica C on superconducting pnictides

Here we report the first angle-resolved photoemission measurement on nearly optimally doped multilayer Tl-based superconducting cuprates (Tl-2212 and Tl-1223) and a comparison study to single-layer (Tl-2201) compound. A "kink" in the band dispersion is found in all three compounds but exhibits different momentum dependence for the single-layer and multilayer compounds, reminiscent to that of Bi-based cuprates. This layer number dependent renormalization effect strongly implies that the spin-resonance mode is unlikely to be responsible for the dramatic renormalization effect near the antinodal region.

The low-energy electronic structure of the itinerant metamagnet Sr3Ru2O7 is investigated by angle-resolved photoemission and density-functional calculations. We find well-defined quasiparticle bands with resolution-limited linewidths and Fermi velocities up to an order of magnitude lower than in single layer Sr2RuO4. The complete topography, the cyclotron masses, and the orbital character of the Fermi surface are determined, in agreement with bulk sensitive de Haas-van Alphen measurements. An analysis of the dxy band dispersion reveals a complex density of states with van Hove singularities near the Fermi level, a situation which is favorable for magnetic instabilities.

Collision tumors are composed of two histologically distinct neoplasms which present at one location. Collision of a malignant tumor originating outside the central nervous system with a primary intracranial neoplasm is a rare event. Here we report on a CPA schwannoma containing a metastasis of adenocarcinoma in a 57-years old woman. Searching for the primary tumor resulted in the detection of a carcinoma in the superior lobe of the left lung.

The evolution of the electronic structure with hole doping in the single‐layer cuprate Bi2Sr2−xLaxCuO6+δ(Bi2201) has been studied by angle‐resolved photoemission spectroscopy measurements. Results for lightly‐doped Bi2201 are compared with the results on other families of cuprate superconductors.

To date, angle-resolved photoemission spectroscopy has been successful in identifying energy scales of the many-body interactions in correlated materials, focused on binding energies of up to a few hundred meV below the Fermi energy. Here, at higher energy scale, we present improved experimental data from four families of high-Tc superconductors over a wide doping range that reveal a hierarchy of many-body interaction scales focused on: the low energy anomaly ("kink") of 0.03-0.09eV, a high energy anomaly of 0.3-0.5eV, and an anomalous enhancement of the width of the LDA-based CuO2 band extending to energies of ~ 2 eV. Besides their universal behavior over the families, we find that all of these three dispersion anomalies also show clear doping dependence over the doping range presented., Comment: 7 pages, 6 figures

A recent highlight in the study of high-T(c) superconductors is the observation of band renormalization or self-energy effects on the quasiparticles. This is seen in the form of kinks in the quasiparticle dispersions as measured by photoemission and interpreted as signatures of collective bosonic modes coupling to the electrons. Here we compare for the first time the self-energies in an optimally doped and strongly overdoped, nonsuperconducting single-layer Bi-cuprate (Bi2Sr2CuO6). In addition to the appearance of a strong overall weakening, we also find that the weight of the self-energy in the overdoped system shifts to higher energies. We present evidence that this is related to a change in the coupling to c-axis phonons due to the rapid change of the c-axis screening in this doping range.

High-resolution angular resolved photoemission data reveal well-defined quasiparticle bands of unusually low weight, emerging in line with the metallic phase of Ca(3)Ru(2)O(7) below approximately 30 K . At the bulk structural phase transition temperature of 48 K, we find clear evidence for an electronic instability, gapping large parts of the underlying Fermi surface that appears to be nested. Metallic pockets are found to survive in the small, non-nested sections, constituting a low-temperature Fermi surface with 2 orders of magnitude smaller volume than in all other metallic ruthenates. The Fermi velocities and volumes of these pockets are in agreement with the results of complementary quantum oscillation measurements on the same crystal batches.

Conservation laryngeal surgery is an increasingly available alternative for the treatment of laryngeal cancer. Understanding anatomy of laryngeal lymph drainage is essential for clinicians to diagnose, grade and surgically manage the laryngeal cancer. Although the lymphatic drainage of the larynx has been extensively studied, few studies revealed the relationship of the lymphatic drainage between various parts of the larynx. The distribution of lymphatic vessels in the inferior surface of the vocal cord also remains unclear. The aim of this study was to investigate the communication of the lymphatic networks between the vocal cord, the supraglottic and subglottic parts of the larynx, paying special attention to the lymphatic drainage of the inferior surface of the vocal cord. Eighteen larynx specimens from 18 fresh fetal cadavers were manually injected with prassion blue solution into the mucosal or submucosal layer of the larynx in order to reveal the lymphatic vessels in the inner larynx. We found that a rich lymphatic network is present in the inferior surface of the vocal cord, and the lymphatic networks in the superior and inferior surfaces of the vocal cord appear as two different patterns. These findings provide an anatomical basis for the design of a partial or conservation laryngeal surgery, particularly when considering the precise resection margin.

Angle-resolved photoemission spectroscopy on optimally doped Bi(2)Sr(2)Ca(0.92)Y(0.08)Cu(2)O(8+delta) uncovers a coupling of the electronic bands to a 40 meV mode in an extended k-space region away from the nodal direction, leading to a new interpretation of the strong renormalization of the electronic structure seen in Bi2212. Phenomenological agreements with neutron and Raman experiments suggest that this mode is the B(1g) oxygen bond-buckling phonon. A theoretical calculation based on this assignment reproduces the electronic renormalization seen in the data.

A modified quark meson coupling (MQMC) model is extended to include Lambda hyperons and Xi hyperons. The extended model is then used to study the equation of state (EOS) for strange hadronic matter. A weak Lambda-Lambda interaction deduced from recent observation of He-6(LambdaLambda) double hypernucleus is adopted in the calculation. The resultant EOS is compared with that deduced from a strong Lambda-Lambda interaction. It is found that while the system with the strong Lambda-Lambda interaction is more deeply bound than ordinary nuclear matter due to the opening of new degrees of freedom, the system with the weak Lambda-Lambda interaction is rather loosely bound compared to the latter. It is necessary to introduce the strange mesons sigma(*) and phi in the MQMC model to properly describe the interaction between the hyperons in either strong or weak Lambda-Lambda interaction cases.

To study the correlation between the expression of p21, p53, MDM2 gene products and the initiation and progression of human astrocytomas.The expression of P21, P53, MDM2, and proliferative cell nuclear antigen (PCNA) labeling index using immunohistochemistry in 41 paraffin embedded human astrocytoma samples. As well as the expression of p21 mRNA using mRNA in situ hybridization in 24 fresh human astrocytoma samples stored at -70 degrees C were investigated. In immunohistochemistry, we divided whole tumor cells by positive tumor cell nuclei to obtain labeling index (LI), in this way we could understand the protein product expression of gene in astrocytoma in different patients. In mRNA in situ hybridization, the expression of p21 mRNA was scored according to the rough percentage of positive cells.In p21 mRNA in situ hybridization, the positive staining was present in 87.5%. In immunohistochemistry, positive P21, P53, MDM2, and PCNA staining were presented in 75.6%, 68.3%, 65.9%, 100% respectively. Higher levels of P21 protein expression were seen in higher histological grade (P = 0.001). The association between P21 expression positively correlated with proliferation index. But not with P53 expression and MDM2 expression. The association between P53 expression and proliferation indices were statistically significant, but the expression of P53 was not related to tumor grade. There was no association between MDM2 expression and grade, or cellular proliferation index. Linear stepwise regression analysis showed the parameters affecting tumor grade were PCNA LI (P = 0.000) and P21 LI (P = 0.001).(1) Both p21 mRNA and P21 protein were overexpressed in human astrocytomas, the overexpression was related to cellular proliferation index, but was not related to P53 expression, suggesting there could be P53-independent pathway to induce the P21 expression, in addition, the overexpression of P21 alone appeared insufficient to suppress tumor growth, provided the participation of PCNA. (2) The expression of P53 protein was associated with proliferation indices, but was not with the tumor malignancy, this indicated that the inactivation of P53 might be the early event in the growth of human astrocytomas. (3) P21 labeling index and cellular proliferation index influenced the tumor histological grade, our data indicated that p21 gene might play a role in the progression of human astrocytomas.

The low-energy electronic structure of the nearly optimally doped trilayer cuprate superconductor Bi(2)Sr(2)Ca(2)Cu(3)O(10+delta) is investigated by angle-resolved photoemission spectroscopy. The normal state quasiparticle dispersion and Fermi surface and the superconducting d-wave gap and coherence peak are observed and compared with those of single- and bilayer systems. We find that both the superconducting gap magnitude and the relative coherence-peak intensity scale linearly with T(c) for various optimally doped materials.

The first angle-resolved photoemission spectroscopy results from MgB2 single crystals are reported. Along the GammaK and GammaM directions, we observed three distinct dispersive features approaching the Fermi energy. These can be assigned to the theoretically predicted sigma (B 2p(x,y)) and pi (B 2p(z)) bands. In addition, a small parabolic-like band is detected around the Gamma point, which can be attributed to a surface-derived state. The overall agreement between our results and the band calculations suggests that the electronic structure of MgB2 is of a conventional nature, thus implying that electron correlations are weak and may be of little importance to superconductivity in this system.

With significantly improved sample quality and instrumental resolution, we clearly identify in the ( pi,0) photoemission spectra from YBa(2)Cu(3)O(6.993), in the superconducting state, the long-sought "peak-dip-hump" structure. This advance allows us to investigate the large a-b anisotropy of the in-plane electronic structure including, in particular, a 50% difference in the magnitude of the superconducting gap that scales with the energy position of the hump feature. This anisotropy, likely induced by the presence of the CuO chains, raises serious questions about attempts to quantitatively explain the YBa(2)Cu(3)O(7-delta) data from various experiments using models based on a perfectly square lattice.

The electronic structure of heavily overdoped Bi(2)Sr(2)CaCu(2)O(8+delta) is investigated by angle-resolved photoemission spectroscopy. The long-sought bilayer band splitting in this two-plane system is observed in both normal and superconducting states, which qualitatively agrees with the bilayer Hubbard model calculations. The maximum bilayer energy splitting is about 88 meV for the normal state feature, while it is only about 20 meV for the superconducting peak.

We report a high-resolution angle-resolved photoemission spectroscopic study of the electron-doped ( n-type) cuprate superconductor Nd1.85Ce0.15CuO4. We observe regions along the Fermi surface where the near- E(F) intensity is suppressed and the spectral features are broad in a manner reminiscent of the high-energy "pseudogap" in the underdoped p-type (hole doped) cuprates. However, instead of occurring near the (pi,0) region, as in the p-type materials, this pseudogap falls near the intersection of the underlying Fermi surface with the antiferromagnetic Brillouin zone boundary.

We have performed angle resolved photoelectron spectroscopy on the electron doped cuprate superconductor Nd1.85Ce0.15CuO4. A comparison of the leading edge midpoints between the superconducting and normal states reveals a small, but finite shift of 1.5-2 meV near the ( pi,0) position, but no observable shift along the zone diagonal near ( pi/2, pi/2). This is interpreted as evidence for an anisotropic superconducting gap in the electron doped materials, which is consistent with the presence of d-wave superconducting order in this cuprate superconductor.

The question of pseudovector versus pseudoscalar coupling schemes for the kaon-hyperon-nucleon interaction is re-examined for the reaction $\gamma p\to K^+ \Lambda$ in several isobaric models. These models typically include Born terms, $K^*$- and $K_1$-exchange in the t-channel, and a few different combinations of spin-1/2 baryon resonances in the $s$- and $u$-channels. The coupling constants are obtained by fitting to a large data set. We find that both pseudoscalar and pseudovector couplings can allow for a satisfactory description of the present database. The resulting coupling constants, $g_{K\Lambda N}$ and $g_{K\Sigma N}$, in the pseudovector coupling scheme are smaller than those predicted using flavor SU(3) symmetry, but consistent with the values obtained in a QCD sum rule calculation., Comment: 11 pages, 4 figures. to appear in Phys. Rev. C

The violation of the scaling law for the electric and magnetic form factors of the proton are examined within the cloudy bag model. The suppression of the ratio of the electric and magnetic form factors is natural in the bag model. The pion cloud plays a moderate role in understanding the recent data from TJNAF., Comment: 8 pages, REVTeX, 2 figures included

The quark mass dependence of nucleon magnetic moments is explored over a wide range. Quark masses currently accessible to lattice QCD, which lie beyond the regime of chiral perturbation theory (chiPT), are accessed via the cloudy bag model (CBM). The latter reproduces the leading nonanalytic behavior of chiPT, while modeling the internal structure of the hadron under investigation. We find that the predictions of the CBM are succinctly described by the simple formula, \mu_N(m_\pi) = \mu^{(0)}_N / (1 + \alpha m_\pi + \beta m_\pi^2), which reproduces the lattice data, as well as the leading nonanalytic behavior of chiPT. As this form also incorporates the anticipated Dirac moment behavior in the limit m_\pi \to \infty, it constitutes a powerful method for extrapolating lattice results to the physical mass regime., Comment: Revised version accepted for publication includes a new section demonstrating extrapolations of lattice QCD results

In-medium nucleon electromagnetic form factors are calculated in the quark meson coupling model. The form factors are typically found to be suppressed as the density increases. For example, at normal nuclear density and $Q^2 \sim 0.3 { GeV}^2$, the nucleon electric form factors are reduced by approximately 8% while the magnetic form factors are reduced by only 1 - 2%. These variations are consistent with current experimental limits but should be tested by more precise experiments in the near future., 14 pages, latex, 3 figures

Possible variations of the quark-meson coupling (QMC) model are examined in which the bag constant decreases in the nuclear medium. The reduction is supposed to depend on either the mean scalar field or the effective mass of the nucleon. It is shown that the electric and magnetic radii of the bound nucleon are almost linearly correlated with the bag constant. Using the fact that the size of the bound nucleon inside a nucleus is strongly constrained by $y$-scaling data in quasielastic, electron-nucleus scattering, we set a limit for the reduction allowed in the bag constant for these two models. The present study implies that the bag constant can decrease up to 10--17 % at average nuclear density, depending on the details of the model., Comment: 31 pages including 4 ps figures, to appear in Nucl.Phys.A

The kaon photoproduction process {gamma}{ital p}{r_arrow}{ital K}{sup +}{Lambda} is studied in a momentum-projected color dielectric quark model. In contrast to phenomenological analyses, only a few Feynman diagrams are used, yet the diagrams include form factors derived from quark wave functions. The predicted cross sections are close to experiment. The unitarization of the Born diagrams, which effectively includes the {ital K}{Lambda} final-state interaction, is found to be important in the prediction of the {Lambda} polarization. It is concluded that only a small number of graphs is needed to explain the basic physics as long as a realistic model of the baryon structure and final-state interactions are included.

We report on the ultrafast dynamics of magnetic order in a single crystal of CuO at a temperature of 207 K in response to strong optical excitation using femtosecond resonant x-ray diffraction. In the experiment, a femtosecond laser pulse induces a sudden, nonequilibrium increase in magnetic disorder. After a short delay ranging from 400 fs to 2 ps, we observe changes in the relative intensity of the magnetic ordering diffraction peaks that indicate a shift from a collinear commensurate phase to a spiral incommensurate phase. These results indicate that the ultimate speed for this antiferromagnetic re-orientation transition in CuO is limited by the long-wavelength magnetic excitation connecting the two phases., Accepted by Physical Review Letters (Dec. 2, 2011)

We apply the chiral color dielectric model to low- and medium-energy scattering within the coupled $\pi$N and $\pi\Delta$ system. Dynamic baryon states in which quarks are confined by the scalar color-dielectric field are constructed in Fock space. Spurious motion of the center of mass is eliminated by constructing momentum eigenstates via a Peierls-Yoccoz projection. The relativistic Lippmann-Schwinger equation is solved for the complex energies of the T matrix poles, and the pole positions of the nucleon and delta are used to fix the few parameters of the model. The $S$- and $P$-wave phase shifts, the bare N and $\Delta$ masses, the renormalized $\pi$NN and $\pi$N$\Delta$ coupling constants, and the $\pi$NN and $\pi$N$\Delta$ vertex functions are predicted. nucleon and delta are used to fix the few parameters of the model. The $S$- and $P$-wave phase shifts, the bare N and $\Delta$ masses, the renormalized $\pi$NN and $\pi$N$\Delta$ coupling constants, and the $\pi$NN and $\pi$N$\Delta$ vertex functions are predicted., Comment: 25 pages, 5 figures

The Vincent--Phatak procedure for solving the momentum-space Schrodinger equation with combined Coulomb-plus-short-range potentials is extended to angular momentum states coupled by an optical potential---as occurs in spin 1/2 times 1/2 scattering. A generalization of the Blatt--Biedenharn phase shift parameterization is derived and applied to 500 MeV polarized-proton scattering from He3 and C13. The requisite high-precision partial-wave expansions and integrations are described., 13 pages

Pion-nucleus bound states are investigated in momentum space using a microscopic optical potential with energy dependences and nonlocalities arising from elementary potential models. We confirm the existence of deep, hybrid Coulomb-nuclear 1[ital s], 2[ital s], and 2[ital p] bound states, but find them to be considerably broader ([similar to]20--300 %) than reported previously for other potentials and slightly ([similar to]7%) more bound. Although the states still remain nonoverlapping, their larger widths may affect experimental searches.

Specimens from 25 patients with squamous cell carcinoma of the oral cavity were examined immunohistochemically, using Streptavidin-Biotin-Peroxidase Complex (ABC) with a series of monoclonal antibodies. Subsets of the infiltrating T lymphocytes in cancer tissues were identified and analysed. We found that, T cell infiltration was predominant. The degree of T cell infiltration was correlated well to the differentiation of cancer and a significant difference existed in OKT 3 + count between the better and the poorer differentiated tumors. Comparing with OKT4+, OKT8+ cells were predominant around cancer nest, the ratio is 1:2. Our results suggest that T cell subsets play a key role in immune response to tumor. Variable quantities and ratio of T subset might be associated with immune regulation imbalance, and reflected malignant grade of cancer and prognosis of the patients.

It is well accepted that postischemic reperfusion promotes functional and morphological impairment which may be related to oxygen free-radical-mediated membrane damage. A new purified bioactive compound, calcitonin-gene-related peptide (CGRP), is known to be not only a potent vasodilator but also a cytoprotective agent. This study was designed to observe whether CGRP has a protective effect on the ischemic kidney. Male Sprague-Dawley rats were subjected to a 45-min period of renal ischemia followed by 60 min of reperfusion. At the beginning of the reperfusion, 12 rats were given intravenous saline and served as controls whereas 5 rats were given CGRP, 10 micrograms/kg intravenously. After reperfusion the kidneys were removed for light- and electronmicroscopy, and the lipid peroxidation product malonaldehyde (MDA) was assayed by thiobarbituric acid (TBA) colorimetry. The results demonstrated that the serum creatinine (Scr) and renal MDA content in the CGRP group were significantly lower than those in the control group. The mean values for Scr were 0.75 +/- 0.09 vs 0.93 +/- 0.05 mg/dL or 62.8 +/- 9.7 vs 82.2 +/- 4.4 mumol/L (p less than 0.05), respectively; while the mean values for MDA were 18.71 +/- 2.13 vs 30.32 +/- 1.78 nmol/100 mg (ww) (p greater than 0.05), respectively. The same signals of free radicals in the ischemic-reperfused kidney with or without CGRP were found by electron spin resonance. Morphological studies demonstrated that the treatment with CGRP ameliorated the ischemic-reperfusion injury to both renal brush borders and mitochondria. The results showed that CGRP has a protective action on ischemia-reperfusion renal injury by decreasing lipid peroxidation of membranes and suggest that it may be a beneficial agent for therapy of acute renal failure.

The sella turcica region is an anatomical site preferential for various types of intracranial tumors. Pathological analysis of 1458 cases of tumor in this region is presented. They comprised 20.16% of the intracranial tumors. Among them, 846(59.1%) were pituitary adenomas, 433(29.7%) craniopharyngiomas, 91(6.2%) meningiomas and 42(2.9%) germinomas. In pituitary adenomas, chromophobe adenoma was predominant, mixed cell adenoma next and no basophilic adenoma was observed. Of craniopharyngiomas they were divided into cystic, partly solid and cystic, and calcified types grossly and histologically into adamantinomatous, squamous and calcified types. In this kind of tumor, well differentiated cells were consistent to the clinical benign course. For meningiomas, histologically meningotheliomatous type was most common in this region. In previous reports, germinomas in the sella turcica region were so-called ectopic pinealoma. Now it is well known that this tumor arises from germ cells, hence, the synonym "ectopic pinealoma" is obsolete. The germinomas in the sella turcica region accounted for 44.68% of all intracranial germinomas. Microscopic picture of this tumor was similar to those of seminoma of the testicle and dysgerminoma of the ovary. Although gliomas, teratomas, giant cell tumors and chondromas were uncommon in the sella turcica region, the authors believe that they should be considered in the differential diagnosis of tumors in the sella turcica region.

The electronic structure of the layered perovskite related compound SrNbO 3.45 has been investigated by angle-resolved photoemission spectroscopy. Two bands near the Fermi level with very different behavior were observed: along Λ-X, one band exhibits no discernible dispersion, whereas the other disperses strongly and crosses the Fermi level. No dispersion appears along the Λ-Y direction.

We calculate electromagnetic form factors of the proton bound in specified orbits for several closed shell nuclei. The quark structure of the nucleon and the shell structure of the finite nuclei are given by the QMC model. We find that orbital electromagnetic form factors of the bound nucleon deviate significantly from those of the free nucleon., Comment: 12 pages including 4 ps figures