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X-ray photoelectron and KLL Auger spectra were measured for the K^{+} and Cl^{-} ions in aqueous KCl solution. While the XPS spectra of these ions have similar structures, both exhibiting only weak satellites near the main line, the Auger spectra differ dramatically. Contrary to the chloride case, a very strong extra peak was found in the Auger spectrum of K^{+} at the low kinetic energy side of the ^{1}D state. Using the equivalent core model and ab initio calculations this spectral feature was assigned to electron transfer processes from solvent water molecules to the solvated cation. The observed charge transfer processes are suggested to play an important role in charge redistribution following single and multiple core-hole creation in atoms and molecules placed into environment.
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We present magnetization, specific heat, and (27)Al NMR investigations on YbFe2Al10 over a wide range in temperature and magnetic field. The magnetic susceptibility at low temperatures is strongly enhanced at weak magnetic fields, accompanied by a ln(T0/T) divergence of the low-T specific heat coefficient in zero field, which indicates a ground state of correlated electrons. From our hard-x-ray photoemission spectroscopy study, the Yb valence at 50 K is evaluated to be 2.38. The system displays valence fluctuating behavior in the low to intermediate temperature range, whereas above 400 K, Yb(3+) carries a full and stable moment, and Fe carries a moment of about 3.1 µB. The enhanced value of the Sommerfeld-Wilson ratio and the dynamic scaling of the spin-lattice relaxation rate divided by T[(27)(1/T1T)] with static susceptibility suggests admixed ferromagnetic correlations. (27)(1/T1T) simultaneously tracks the valence fluctuations from the 4f Yb ions in the high temperature range and field dependent antiferromagnetic correlations among partially Kondo screened Fe 3d moments at low temperature; the latter evolve out of an Yb 4f admixed conduction band.
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The electronic structure of IrO2 has been investigated using hard x-ray photoelectron spectroscopy and density-functional theory. Excellent agreement is observed between theory and experiment. We show that the electronic structure of IrO2 involves crystal field splitting of the iridium 5d orbitals in a distorted octahedral field. The behavior of IrO2 closely follows the theoretical predictions of Goodenough for conductive rutile-structured oxides [J. B. Goodenough, J. Solid State Chem. 3, 490 (1971).
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We study the photon generation in a transmission line oscillator coupled to a driven qubit in the presence of a dissipative electromagnetic environment. It has been demonstrated previously that a population inversion in the qubit can lead to a lasing state of the oscillator. Here we show that the circuit can also exhibit the effect of "lasing without inversion." It arises since the coupling to the dissipative environment enhances photon emission as compared to absorption, similar to the recoil effect predicted for atomic systems. While the recoil effect is very weak, and so far elusive, the effect described here should be observable with realistic circuits. We analyze the requirements for system parameters and environment.
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The substitution of vanadium in vanadium dioxide VO2 influences the critical temperatures of structural and metal-to-insulator transitions in different ways depending on the valence of the dopant. Rhenium adopts valence states between +4 and +7 in an octahedral oxygen surrounding and is particularly interesting in this context. Structural investigation of V1-xRexO2 solid solutions (0.01 ≤ x ≤ 0.30) between 80 and 1200 K using synchrotron X-ray powder diffraction revealed only two polymorphs that resemble VO2: the low-temperature monoclinic MoO2-type form (space group P21/c), and the tetragonal rutile-like form (space group P42/mnm). However, for compositions with 0.03 < x ≤ 0.15 a phase separation in the solid solution was observed below 1000 K upon cooling down from 1200 K, giving rise to two isostructural phases with slightly different lattice parameters. This is reflected in the appearance of two metal-to-insulator transition temperatures detected by magnetization and specific heat measurements. Comprehensive X-ray photoelectron spectroscopy studies showed that an increased amount of Re leads to a change in the Re valence state from solely Re6+ at a low doping level (≤3 at% Re) via mixed-valence states Re4+/Re6+ for at least 0.03 < x ≤ 0.10, up to nearly pure Re4+ in V0.70Re0.30O2. Thus, compositions V1-xRexO2 with only one valence state of Re in the material (Re6+ or Re4+) can be obtained as a single phase, while intermediate compositions are subjected to a phase separation, presumably due to different valence states of Re.
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Correction for 'Composition-dependent charge transfer and phase separation in the V1-xRexO2 solid solution' by D. Mikhailova, et al., Dalton Trans., 2017, 46, 1606-1617.
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Xylem cavitation in winter and recovery from cavitation in the spring were visualized in two species of diffuse-porous trees, Betula platyphylla var. japonica Hara and Salix sachalinensis Fr. Schm., by cryo-scanning electron microscopy after freeze-fixation of living twigs. Water in the vessel lumina of the outer three annual rings of twigs of B. platyphylla var. japonica and of S. sachalinensis gradually disappeared during the period from January to March, an indication that cavitation occurs gradually in these species during the winter. In April, when no leaves had yet expanded, the lumina of most of the vessels of both species were filled with water. Many vessel lumina in twigs of both species were filled with water during the period from the subsequent growth season to the beginning of the next winter. These observations indicate that recovery in spring occurs before the onset of transpiration and that water transport through twigs occurs during the subsequent growing season. We found, moreover, that vessels repeat an annual cycle of winter cavitation and spring recovery from cavitation for several years until irreversible cavitation occurs.
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For an examination of the progression of cavitation in large-diameter earlywood vessels of a deciduous ring-porous tree, potted saplings of Fraxinus mandshurica var japonica Maxim. were frozen and then thawed. The changes in the amount and distribution of water in the lumina of the current year's earlywood vessels during the course of the freezing and thawing were visualized by cryo-scanning electron microscopy. When samples were frozen, most of the current year's earlywood vessels were filled with water. After the subsequent thawing, the percentage of cavitated current-year earlywood vessels gradually increased with time. All of the current year's earlywood vessels were cavitated within 24 h, and only limited amounts of water remained in the lumina of earlywood vessels. Similar cavitation of earlywood vessels was observed after thawing of frozen, excised stem pieces. In contrast, many vessels of the current year's latewood retained water in the lumina during freezing and thawing. These observations indicate that the cavitation of the current year's earlywood vessels is not produced during freezing but progresses during rewarming after freezing in F. mandshurica var japonica.
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A simple and sensitive method for determination of organophosphorus pesticides in human urine was developed by detecting the color complexes which resulted from reactions of organophosphorus pesticides and 4-(4-nitrobenzyl)pyridine (NBP) in urine. Based on studies of reaction conditions, e.g. reaction temperature and time, and reagent concentration, a colorimetric method was established. A 0.1-ml volume of NBP (45% in acetone) was added to a 1.0-ml volume of a urine sample, and the mixture was heated at 100 degrees C for 20 min. After cooling, 0.1 ml of tetraethylenepentamine was added. The organophosphorus pesticides showed a characteristic purplish blue color and the coloring complexes which were produced were stable for several hours. Furthermore, these complexes could be determined spectrophotometrically. The detection limits were 0.10-10 microg/ml in urine. The required time for analysis was approximately 30 min for one sample. Comparing the result of the proposed method with those of the GC-MS method, the results were similar for the 12 poisoning cases studied. Thus, the proposed method is useful for detection of these pesticides in critical care practices.
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Colorimetria/métodos , Inseticidas/urina , Compostos Organofosforados , Quelantes , Compostos Cromogênicos , Etilenodiaminas , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Inseticidas/intoxicação , Piridinas , Sensibilidade e Especificidade , EspectrofotometriaRESUMO
Two infants, age 1 year, with acute encephalopathy who showed transient pseudoatrophy of the brain were reported. They each had measles infection, followed by 'mild drowsiness'. Reversible brain atrophy has been observed in patients with undernutrition, dehydration, and overdoses of steroids and valproic acid. However, these manifestations were very mild and there was no history of drug administration in our patients. The cause of the transient brain pseudoatrophy was unknown. However, activation of glial cells accompanying the measles infection was thought to be one possibility to see high value of neopterin (51 pmol/l) in the cerebrospinal fluid in one case. Although 'mild drowsiness' is not a rare manifestation in patients with measles infection, it is probable that their 'mild drowsiness' is caused by acute encephalopathy like in our cases. Thus, we recommend that computed tomography scanning or magnetic resonance imaging is performed in patients showing 'mild drowsiness' during measles infection.
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Atrofia/etiologia , Atrofia/patologia , Encéfalo/patologia , Encéfalo/virologia , Encefalite Viral/etiologia , Encefalite Viral/patologia , Sarampo/complicações , Doença Aguda , Atrofia/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Progressão da Doença , Encefalite Viral/fisiopatologia , Feminino , Humanos , Lactente , Masculino , Recuperação de Função Fisiológica , Fatores de Tempo , Tomografia Computadorizada por Raios XRESUMO
UV-C (254 nm)- and UV-B (280-320 nm)-light were irradiated onto bright-yellow capitula of dyer's saffron and their effects on carthamine accumulation compared. UV-C light promotes reddening of florets more prominently than UV-B light, yielding higher amounts of carthamine after the radiation process. The enhancement of carthamine synthesis by UV-C light was investigated on cellulose columns loaded with floret extracts under O2-sufficient or O2-deficient conditions. Externally charged O2 inhibits the UV-C- stimulated carthamine formation. The results are discussed in relation to light stimulation of carthamine synthesis in dyer's saffron florets.
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Chalcona/análogos & derivados , Cicloexanos/metabolismo , Glucosídeos/metabolismo , Especiarias/efeitos da radiação , Raios Ultravioleta , Anaerobiose , Cicloexanos/isolamento & purificação , Glucosídeos/isolamento & purificação , Cinética , Luz , Oxigênio/farmacologia , Pigmentos Biológicos/biossínteseRESUMO
Agarose gel electrophoresis and immunofixation of CSF and serum from 16 patients aged from 1 day to 13 years with CNS infectious diseases (5 with purulent meningitis, 5 with aseptic meningitis, 4 with acute encephalitis, 1 with subdural empyema and 1 with SSPE) revealed oligoclonal IgG bands in 10 cases. In 4 cases, a high CSF/serum albumin ratio was recognized without an increase of IgG-index, probably representing a systemic immune response. Neither IgA nor IgM bands were recognized. IgG light chain was examined in 7 cases and IgG kappa bands predominated in 6 cases. IgG lambda bands predominance presented in only one case. Free IgG kappa or lambda chain was not found. These results suggested that the measurement of not only IgG-index but oligoclonal bands may have a diagnostic usefulness to know about local production of immunoglobulins in CSF.
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Doenças do Sistema Nervoso Central/imunologia , Líquido Cefalorraquidiano/imunologia , Cadeias Leves de Imunoglobulina/análise , Imunoglobulinas/análise , Infecções/imunologia , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-NascidoRESUMO
It has been assumed that a high dose of OK-432 can be safely injected into tumor tissues or intraperitoneally under general anesthesia. Among 40 patients with advanced carcinoma of the stomach, high doses of OK-432 were injected into the tumor in six and intraperitoneally in 34. Circulatory shock associated with subsequent disseminated intravascular coagulation (DIC) developed within 3 days in one of the former and in two of the latter group. Hypovolemic shock was initially considered to indicate that hypovolemia actually existed in these three patients. However, the shock state with DIC persisted even after the blood volume had been corrected. Gram-negative bacteremia was verified in two of the patients. The shock and DIC seen in these patients could have been attributed to septicemia through either the necrotic tumor or the intestinal wall showing increased permeability as a result of the drug. When and if a high dose of OK-432 is administered locally, the prophylaxis of infection seems to be of crucial importance in order to avoid such complications as those reported above.
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Produtos Biológicos/efeitos adversos , Coagulação Intravascular Disseminada/etiologia , Picibanil/efeitos adversos , Neoplasias Gástricas/terapia , Adulto , Idoso , Feminino , Humanos , Injeções Intraperitoneais , Masculino , Pessoa de Meia-Idade , Picibanil/administração & dosagemRESUMO
Ulcerative colitis(UC) is an ulcero inflammatory disorder of unknown etiology affecting only the mucosa and submucosa of colon and, with Crohn's disease, is included in the term idiopathic inflammatory bowel disease. The macroscopic and microscopic features vary according to the stage of the disease process, and an acute phase and a chronic or resolving phase can be recognized. The main differential diagnosis of UC is with colorectal Crohn's disease. The most feared long-term complication of UC is cancer. The progression of UC to carcinoma is closely associated with dysplasia arising in multiple sites. The dysplastic changes should be distinguished from the epithelial changes resulting from regenerative atypia, and the evaluation of these changes is difficult. P53 immunohistochemical staining is helpful in confirming the presence of dysplasia. Molecular events in colorectal carcinogenesis of UC may be somewhat different from those of so-called adenoma-carcinoma sequence.
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Colite Ulcerativa/patologia , Colite Ulcerativa/diagnóstico , Neoplasias do Colo/etiologia , Diagnóstico Diferencial , Humanos , Mucosa Intestinal/patologia , Perda de Heterozigosidade , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/genéticaRESUMO
Renal hypouricemia (MIM 220150) is an inherited disorder characterized by low serum uric acid levels and has severe complications such as exercise-induced acute renal failure and urolithiasis. We have previously reported that URAT1/SLC22A12 encodes a renal urate-anion exchanger and that its mutations cause renal hypouricemia type 1 (RHUC1). With the large health-examination database of the Japan Maritime Self-Defense Force, we found two missense mutations (R198C and R380W) of GLUT9/SLC2A9 in hypouricemia patients. R198C and R380W occur in highly conserved amino acid motifs in the "sugar transport proteins signatures" that are observed in GLUT family transporters. The corresponding mutations in GLUT1 (R153C and R333W) are known to cause GLUT1 deficiency syndrome because arginine residues in this motif are reportedly important as the determinants of the membrane topology of human GLUT1. Therefore, on the basis of membrane topology, the same may be true of GLUT9. GLUT9 mutants showed markedly reduced urate transport in oocyte expression studies, which would be the result of the loss of positive charges in those conserved amino acid motifs. Together with previous reports on GLUT9 localization, our findings suggest that these GLUT9 mutations cause renal hypouricemia type 2 (RHUC2) by their decreased urate reabsorption on both sides of the renal proximal tubule cells. However, a previously reported GLUT9 mutation, P412R, was unlikely to be pathogenic. These findings also enable us to propose a physiological model of the renal urate reabsorption via GLUT9 and URAT1 and can lead to a promising therapeutic target for gout and related cardiovascular diseases.