The case of GaN-based capacitor nanoscale structures is presented

The case of GaN-based capacitor nanoscale structures is presented taking into account the boundary conditions imposed as well as the effect of geometry. The results in this example point to corrections in the piezoelectric and electrostrictive coefficients higher than 0.3 pm V(-1) and 2.6 x 10(-22) m(2) V(-2), respectively. (C) 2011 American Institute of Physics. [doi:10.1063/1.3524259]“
“Purpose:

To retrospectively evaluate the diagnostic performance of power Doppler ultrasonography (US) in depicting vascularity and to determine whether the combination of vascularity and suspicious gray-scale

US features is more useful in predicting thyroid malignancy than are VS-6063 in vivo gray-scale features alone.

Materials and Methods:

This was an institutional review board-approved retrospective study, with Lonafarnib mw waiver of informed consent. A total of 1

083 thyroid nodules in 1024 patients (median age, 51 years; range, 16-83 years), consisting of 886 women (median age, 50 years; range, 16-83 years) and 138 men (median age, 53 years; range, 19-74 years), were included. Nodules with marked hypoechogenicity, noncircumscribed margins, microcalcifications, and taller-than-wide shape were classified as suspicious according to gray-scale US criteria. Vascularity was classified as none, peripheral, and intranodular. The diagnostic performance of

gray-scale and power Doppler US features was compared and classified INCB018424 price as follows: criterion 1, any single suspicious gray-scale US feature; criterion 2, addition of any vascularity as one of the suspicious features to criterion 1; criterion 3, addition of peripheral vascularity to criterion 1; criterion 4, addition of intranodular vascularity to criterion 1; criterion 5, addition of no vascularity to criterion 1; criterion 6, American Association of Clinical Endocrinologists and Associazione Medici Endocrinology guidelines-all hypoechoic nodules with at least one of the following US features: irregular margins, intranodular vascular spots, taller-than-wide shape, or microcalcifications.

Results:

Of 1083 nodules, 814 were benign and 269 were malignant. Intranodular vascularity was frequently seen in benign nodules and no vascularity was more frequent in malignant nodules (P<.0001, respectively). The area under the receiver operating characteristic curve (A(z)) of criterion 1 was superior (A(z) = 0.851) to that of criteria 2 (A(z) = 0.634), 3 (A(z) = 0.752), 4 (A(z) = 0.733), 5 (A(z) = 0.718), and 6 (A(z) = 0.806) (P<.0001).

Conclusion:

Vascularity itself or a combination of vascularity and gray-scale US features was not as useful as the use of suspicious gray-scale US features alone for predicting thyroid malignancy.

A series of N-substituted cis-tetra- and cis-hexahydrophthalazino

A series of N-substituted cis-tetra- and cis-hexahydrophthalazinone derivatives

have been reported as novel, selective PDE-4 inhibitors with potent anti-inflammatory activity. In order to gain further insights into the structural requirements of novel series of N-substituted cis-tetra and cis-hexahydrophthalazinone derivatives as PDE-4 inhibitors, a three-dimensional quantitative structure activity BAY 73-4506 manufacturer relationship (3D-QSAR) was performed using Genetic Function Approximation (GFA). The QSAR model was generated using a training set of 45 molecules and the predictive ability of the resulting each model was assessed using a test set of 9 molecules. The internal and external consistency of final QSAR model was 0.675 and 0.750 respectively. Analysis of results from the present QSAR study indicates that shape and structural descriptors strongly govern the PDE-4 enzyme inhibitory activity. This QSAR study highlights the structural features required for PDE-4 enzyme inhibition and may be useful for design of potent PDE-4 inhibitors.”
“We demonstrate the possibility of doubling the areal density of information in magnetic patterned media by stacking decoupled in-plane and perpendicular-to-plane magnetized layers. Each dot can be set in four magnetostatically equivalent configurations, yielding a storage capability of two-bits per dot. Magnetic force microscopy analyses show that the magnetic signal from the out-of-plane

magnetized layer is dominant right above the dots, whereas, the signal from the in-plane magnetized layers is largest above the spacing selleck products between dots. This results in an optimal use of the storage OICR-9429 space and in an increase of the areal density with weak loss in readout signal-to-noise ratio. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3572259]“
“Objective: Maximum seizure

control, preservation of cognition, and prevention of developmental hindrance are major aims of the pharmacological treatment of children and adolescents with epilepsy. Herewith we introduce the junior version of EpiTrack, a 12- to 15-minute screening test for monitoring the cognitive effects of antiepileptic drug treatment in children and adolescents aged 6 to 18.

Methods: The test, which comprises six subtests (Speed, Flexibility, Planning, Response Inhibition, Word Fluency, Working Memory), was administered to 277 children and adolescents aged 6-18 years, 111 of whom were retested after an interval of 3 months. For the first clinical validation, 155 patients (46% idiopathic/benign, 62% seizure free) were evaluated.

Results: Standardization and correction for age resulted in a mean score of 33 +/- 2 points, which was no longer correlated with age (r = 0.005). The retest practice effect was 0.7 +/- 2 points, and the reliability r(tt) = 0.78. Factor analysis indicated one executive factor in controls and patients. In the epilepsy group, 50% of the patients were impaired (controls 14%).

The disappearance of garenoxacin from plasma in female SD rats wa

The disappearance of garenoxacin from plasma in female SD rats was significantly faster than that in male SD rats after a single intravenous injection of garenoxacin (5 mg/kg). The systemic clearance of garenoxacin in female rats was approximately threefold larger than that of male rats (2.43 +/- A 0.31 and 0.87 +/- A 0.06 l/h/kg, respectively), suggesting the existence of sex-related differences in the pharmacokinetics

of garenoxacin. When rats received a constant-rate infusion of garenoxacin, the contribution of biliary and renal excretion of garenoxacin was small, and no significant difference in the biliary (CL(BILE)) clearance of garenoxacin was observed between male and female SD rats. The metabolic clearance [CL(M (SULF))] of garenoxacin to garenoxacin PLX3397 concentration sulfate conjugate (which is mainly excreted into the bile) in female SD rats was 8.5-fold larger than that in male SD rats (27.9 +/- A 2.94 and 3.28 +/- A 0.07 ml/h/kg, respectively). The CL(BILE) of

garenoxacin was decreased in male and female EHBRs by approximately 50% compared with that in male and female SD rats. These learn more results suggest that sulfate conjugation, but not Mrp2, is mainly involved in the sex-related differences in the pharmacokinetics of garenoxacin.”
“Background: Sepsis and septic shock remain the major causes of morbidity and mortality in intensive care units. One mechanism that leads to organ failure is microcirculatory dysfunction. Erythropoietin (EPO) is a glycoprotein produced by the kidney that primarily regulates erythropoiesis, but it also can exert hemodynamic, anti-inflammatory, and tissue protective effects. We previously reported that administration of EPO to septic mice improves mouse skeletal muscle capillary perfusion and tissue bioenergetics. Tozasertib chemical structure The objective of this study was to explore the potential mechanism(s) involved.

Methods:

Sepsis was induced by intraperitoneal (i.p.) injection of a fecal suspension (12.5 g in 0.5 saline/mouse) in mice. At 18 hours after sepsis induction, a single dose of rHuEPO (400 U/kg) was given to the mice. Mouse capillary perfusion density and nicotinamide adenine dinucleotide (NADH) fluorescence in skeletal muscle were observed using intravital microscopy. Endothelial cells derived from the skeletal muscle were treated with rHuEPO (5 U/mL) and endothelial nitric oxide synthase (eNOS) activation and activity were assessed.

Results: Septic mice had decreased capillary perfusion density and increased tissue NADH fluorescence indicating impaired tissue bioenergetics, whereas animals treated with rHuEPO demonstrated an improvement in capillary perfusion density and decreased skeletal muscle NADH fluorescence.

One hundred and seventy-one students in Educational Sciences were

One hundred and seventy-one students in Educational Sciences were each asked to interview 25 different teachers.

Results: A total of 4273 BAY 11-7082 mouse teachers participated in the study (primary school n = 856; secondary school n = 2562; higher education n = 855). Of all respondents, 59% (2539/4273) had received previous CPR training

with the highest proportion observed in primary schoolteachers (69%) and in the age group 21-30 years (68%). Mandatory CPR training at school was supported by 41% (1751/4273) of the teachers and only 36% was aware that CPR is now formally included in the secondary education curriculum. Sixty-one percent (2621/4273) did not feel capable and was not willing to teach CPR, mainly because of a perceived lack of knowledge in 50% (2151/2621). In addition 69% (2927/4273) felt incompetent to perform correct buy PF-6463922 CPR and 73% (3137/4273) wished more training. Feeling incompetent and not willing to teach was related to the absence of previous training. Primary schoolteachers and the age group 21-30 years were most willing to teach CPR.

Conclusions: Although many teachers mentioned previous CPR training, only a minority of mostly young and primary schoolteachers felt

competent in CPR and was willing to teach it to their students. (C) 2013 Elsevier Ireland Ltd. All rights reserved.”
“The objective of this study was to determine expression and potential functions of alpha(v) and beta(3) integrin subunits in ovine endometrium during the peri-implantation period (days 8-17 after fertilization). The morphologic changes in the endometrium were observed histochemically following haematoxylin/eosin (HE) staining, whereas the expressions of alpha(v) and beta(3) integrin subunits were analysed by RT-PCR, immunohistochemistry

and Western blot. The filamentous conceptus attached to the luminal epithelium (LE) on day 17 of pregnancy, with no differences in endometrial morphology between days 8-12 of pregnancy. However, endometrial Dihydrotestosterone chemical structure glands in the endometrial stroma (S) underwent extensive hyperplasia from day 14 to day 17, increased reductus of the LE with an obvious proliferation of caruncles, and an increased number and diameter of blood vessels (V) in the endometrium. The relative expression levels of alpha(v) and beta(3) integrin subunits mRNA gradually increased until day 16, but sharply declined on day 17. Western blot analysis revealed that the expression pattern of alpha(v) and beta(3) integrin subunit proteins paralleled that of the corresponding mRNA. In addition, immunohistochemical localization of alpha(v) and beta(3) integrin subunits confirmed their presence in the glandular epithelium (GE), LE and endometrial stroma. Immunostaining on LE and stroma varied with the increasing days of pregnancy, with the strongest immunostaining on days 16 and 17.

This years’ American Society for Mass Spectrometry Sanibel meetin

This years’ American Society for Mass Spectrometry Sanibel meeting brought together established scientists who have demonstrated the viability of the top-down approach and its applicability to virtually all segments of the proteome, mixing them with researchers from diverse areas and with the common interest of advancing top-down into the high-throughput proteomics mainstream. Advances in instrumentation

including the orbitrap analyzer, ionization mechanisms, dissociation CX-5461 DNA Damage inhibitor strategies and informatics, as well as a wide variety of applications, were discussed in depth, leading to the inescapable conclusion that the future for top-down is bright.”
“A new actinomycete strain designated as Streptomyces sp. CTF15 was isolated from a saline soil using casein-KNO3 agar medium. The strain Streptomyces sp. CTF15 exhibited promising antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Streptomyces viridochromogens Tu57 and high cytotoxicity (91.2% mortality) against Artimia salina in biological screening. The cultivation of this strain in a 50 L lab fermenter and subsequent isolation and purification by a Sepantronium solubility dmso series of chromatographic techniques and structure elucidation by MS and NMR analysis of the active metabolites

revealed that it is a highly stable producer of resistomycin (1), tetracenomycin D (2) and actinomycin D (3), even under non-optimised culture conditions.

The morphological, microscopic, biochemical and physiological characterisation suggested that the strain CTF15 belongs to the genus Streptomyces. A partial 16S rRNA gene sequence (1429 bp) from the strain CTF15 was determined and found to have high identity (99%) with Streptomyces griseoincarnatus. As such, this is the first report of a strain of S. griseoincarnatus capable of producing Tucidinostat in vivo these three bioactive compounds simultaneously.”
“Expert Rev. Proteomics 10(2), 131-134 (2013) Evaluation of: Wapner RJ, Martin CL, Levy B etal. Chromosomal microarray versus karyotyping for prenatal diagnosis. N. EngL J. Med. 367(23), 2175-2184 (2012). Prenatal diagnosis is now offered to high-risk pregnancies, including advanced maternal age, ultrasound anomalies and positive Down’s syndrome screening, and karyotype on cultured fetal material is the test of choice to screen these pregnancies. However, microscope analysis can only detect gross chromosome abnormalities, highlighting the need for more sensitive techniques. It has recently been established that the higher resolution of microarray-based platforms can increase the diagnostic yield, offering more information to couples, and it is being discussed as a replacement to the standard karyotype.

002) than d 1 of restriction, whereas LH concentration tended to

002) than d 1 of restriction, whereas LH concentration tended to increase in FAT heifers (P = 0.06) until it was similar (P = 0.40) to d 1 of restriction. Repletion also increased concentrations of IGF-1 (P < 0.001), insulin (P < 0.001), and glucose (P < 0.001), whereas concentrations of GH (P < 0.001), NEFA (P < 0.001), and plasma urea nitrogen (P < 0.001) decreased. For both treatments, concentrations of GH after repletion eFT-508 were similar (FAT, P = 0.88; MOD, P = 0.10) to those on d 1 of restriction.

After repletion, FAT condition heifers had decreased concentrations of IGF-1 (P < 0.001), insulin (P < 0.05), and glucose (P < 0.001), but greater concentrations of acetate (P < 0.01) and butyrate (P < 0.05), than MOD heifers. Anestrus or resumption of estrous cycles seems to be activated gradually in response to dietary manipulation, ML323 unrelated to certain metabolite changes.”
“Co-operative

behaviours, such as the production of public goods, are commonly displayed by bacteria in biofilms and can enhance their ability to survive in environmental or clinical settings. Non-co-operative cheats commonly arise and should, theoretically, disrupt co-operative behaviour. Its stability therefore requires explanation, but no mechanisms to suppress cheating within biofilms have yet been demonstrated experimentally. Theoretically, repeated aggregation into groups, interleaved with dispersal and remixing, can increase co-operation via a Simpson’s paradox. That is, an increase in the global proportion of co-operators despite a decrease in within-group proportions, via differential growth of groups. We investigate

the hypothesis that microcolony formation and dispersal produces a Simpson’s paradox that explains bacterial co-operation in biofilms. Using the production of siderophores in Pseudomonas aeruginosa as our model system for co-operation, BI 10773 we use well-documented co-operator and siderophore-deficient cheat strains to measure the frequency of co-operating and cheating individuals, in-situ within-microcolony structures. We detected significant within-type negative density-dependant effects that vary over microcolony development. However, we find no evidence of Simpson’s paradox. Instead, we see clear within-microcolony spatial structure (cheats occupying the interior portions of microcolonies) that may violate the assumption required for Simpson’s paradox that group members share equally in the public good.”
“To investigate the structure-function relationship of pectin during (pre)processing, broccoli samples (Brassica oleracea L. cultivar italica) were subjected to one of the following pretreatments: (i) low-temperature blanching (LTB), (ii) LTB in combination with Ca(2+) infusion. (iii) high-pressure pretreatment (HP), (iv) HP in combination with Ca(2+) infusion, or (v) no pretreatment (control sample), whether or not in combination with a thermal treatment of 15 min at 90 degrees C.

At the metabolite level, differential accumulation of osmotically

At the metabolite level, differential accumulation of osmotically active solutes was observed between the two cultivars; indeed, in Sullu, contents of galactose, inositol, galactinol, proline, and proline Bindarit nmr analogues were higher upon drought stress compared with SS2613. These results point to different drought responses in the cultivars at the leaf level, with, however, similar

tuber yield reductions. The previously shown tolerant clone Sullu lost part of its tolerance under the experimental conditions used here; it was, however, able to maintain an absolute yield three times higher than SS2613.”
“Stroke is one of the leading causes of disability; most are due to atherothrombotic mechanisms. About one third of ischemic strokes are preceded by other stroke or transient ischemic attacks. Stroke survivors are at high risk for vascular events (i.e., cerebrovascular and cardiovascular). Prevention of recurrent stroke and other major vascular events can be accomplished by control of risk factors. Nonetheless, the use of antiplatelet agents remains the fundamental component of secondary stroke prevention strategy in patients with noncardioembolic disease. Currently, the uses of aspirin, clopidogrel, or aspirin plus extended-release buy LCL161 dipyridamole are valid alternatives

for stroke or transient ischemic attack patients. To maximize the beneficial effects of these agents, the treatment should be initiated as early as possible and continue on

a lifelong basis.”
“Flower opening is an event accompanied by morphological changes in petals which include elongation, expansion, and outward-curving. Petal cell growth is a fundamental process that underlies such phenomena, but its molecular mechanism remains largely unknown. Suppression Selumetinib inhibitor subtractive hybridization was performed between petals during the early elongation period (stage 1) and during the opening period (stage 5) in carnation flowers and a pair of subtraction libraries abundant in differentially expressed genes was constructed at each stage. 393 cDNA clones picked up by differential screening out of 1728 clones were sequenced and 235 different cDNA fragments were identified, among which 211 did not match any known nucleotide sequence of carnation genes in the databases. BLASTX search of nucleotide sequences revealed that putative functions of the translational products can be classified into several categories including transcription, signalling, cell wall modification, lipid metabolism, and transport. Open reading frames of 15 selected genes were successfully determined by rapid amplification of cDNA ends (RACE). Time-course analysis of these genes by real-time RT-PCR showed that transcript levels of several genes correlatively fluctuate in petals of opening carnation flowers, suggesting an association with the morphological changes by elongation or curving.

However, results from post-mortem brains may not provide indicati

However, results from post-mortem brains may not provide indication as to whether CXCL12/CXCR4 can cause the degeneration of DA neurons. To examine the role of these chemokines, we determined the levels of CXCL12 and CXCR4 in the SN of MPTP-treated mice. MPTP produced a time-dependent up-regulation of CXCR4 that preceded the loss of DA neurons. These results suggest that CXCL12/CXCR4 may participate in the etiology of PD and indicate a new possible target molecule for PD.”
“Transfer printing is a nanofabrication technique that involves ail assembly process by which a printable layer can be transferred from a transfer

substrate to a device substrate. Future application of transfer printing toward a roll-to-roll printing process of GSK1120212 cell line flexible devices hinges upon the understanding on the mechanisms governing transfer printing quality, which is far from mature. So far, the quality control of transfer printing has been mainly explored via massive experimental trials, which are both time consuming and cost prohibitive.

In this paper, we conduct systematic computational modeling to investigate the governing mechanisms of the transfer printing process. While the existing understanding of transfer printing mainly relies on the differential interfacial adhesion, our results suggest that both interfacial defects (e.g., cracks) and differential interfacial adhesion play pivotal roles in the transfer printing quality. The outcomes of this study define a quality map of transfer printing in the space spanned by the critical mechanical properties and geometrical parameters in a transfer printing see more structure. Such a quality map offers new insights and quantitative guidance for material selection and design strategies to achieve

successful transfer printing. (C) 2009 American Institute of Physics. [doi:10.1063/1.3259422]“
“A growing variety of technical approaches allow control over the expression of selected genes in living organisms. The ability to deliver functional exogenous genes involved in neurodegenerative diseases has opened pathological processes to experimental analysis and targeted therapeutic development in rodent and primate preclinical models. Biological adaptability, economic animal Blasticidin S ic50 use, and reduced model development costs complement improved control over spatial and temporal gene expression compared with conventional transgenic models. A review of viral vector studies, typically adeno-associated virus or lentivirus, for expression of three proteins that are central to major neurodegenerative diseases, will illustrate how this approach has powered new advances and opportunities in CNS disease research.”
“Background: The incidence and predictors of heart failure (HF) after myocardial infarction (MI) with modern post-MI treatment have not been well characterized.

We propose standardized discharge letters, as well as reminders t

We propose standardized discharge letters, as well as reminders to primary

care physicians with precise instructions on the need to complete the immunization series in HBsAg-exposed infants and to evaluate success by determination of anti-HBs antibodies after the last dose.”
“During the past decade, there has been an increased description of Churg Strauss syndrome (CSS) characterized by vascular occlusions possibly linked to the thrombogenic potential of the eosinophil that is poorly appreciated. The purpose of this overview is 3-fold: the first to evaluate the available prevalence of thrombosis in Churg Strauss series, the second to demonstrate that any vascular district may be affected, and the third to describe the pathogenesis of thrombosis in CSS. find more A Pubmed, EMBASE, and Google search of CSS series from 1951 to date revealed a prevalence of arterial occlusion ranging between 3.1% and 18.7% and a prevalence of venous occlusion between 5.8% and 30%, whereas a specific survey for venous thromboembolism in CSS yielded a prevalence of 8.1%.

Eosinophils store and release tissue factor as well as other cationic proteins: the former initiates coagulation while the latter inhibits natural anticoagulant activity and activate platelets eventually culminating in excessive thrombin selleck kinase inhibitor generation and clot formation. In addition, antineutrophil cytoplasmic antibodies may shift the endothelial lining to proadhesive and prothrombotic surface. It is hoped that the review will

represent a basis to foster novel research on this topic.”
“An attempt was made to deposit a nanocoating onto a cotton textile substrate using a layer-by-layer self-assembly approach. Chitosan, a natural biopolymer with polycationic characteristic, was used as a polyelectrolyte along with poly(sodium-4-styrene sulfonate) as an anionic polyelectrolyte for the first time on a textile substrate using this technique. The nanocoated surface was evaluated for surface characteristics such as the contact angle and scanning electron microscopy. The effect of ultrasonication during selleck screening library the intermediate washing steps was explored. Ultrasonication during the washing steps clearly helped in depositing more uniform bilayers onto individual fiber surfaces; this contrasted with the deposition of a continuous coating layer, which was nonuniform and had a lot of surface cracks. The use of this novel method for depositing chitosan onto cotton imparted antimicrobial properties to the fabric without adversely affecting its flexibility, feel, or breathability. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 2793-2799, 2011″
“Background: Alaska Native (AN) children, especially those in the Yukon-Kuskokwim region (YK-AN children), suffer some of the highest rates of invasive pneumococcal disease (IPD) in the world.

DESIGN: Study data came from the National Survey on TB Drug Resis

DESIGN: Study data came from the National Survey on TB Drug Resistance (ENTB-2008), a nationally representative survey conducted during 2008-2009 in nine states with a stratified cluster sampling design.

Samples were obtained for all newly diagnosed cases of pulmonary TB in selected sites. Drug susceptibility testing (DST) was performed for anti-tuberculosis drugs.

RESULTS: DST results were obtained for 75% of the cases. Of these, 82.2% (95%CI 79.5-84.7) were susceptible to all drugs. The prevalence of multidrug-resistant TB (MDR-TB) AR-13324 was estimated at 2.8% (95%CI 1.9-4.0). MDR-TB was associated with previous treatment (OR 3.3, 95%CI 1.1-9.4).

CONCLUSIONS: The prevalence of drug resistance is relatively low in Mexico. ENTB-2008 can be used as a baseline for future follow-up of drug resistance.”
“Background:

Molecular biomarkers associated with knee pain may be useful as diagnostic modalities, prognostic indicators, and Surrogate end points for therapeutic trials. The present study describes a novel complex of fibronectin and aggrecan that is present in the affected knee of patients with pain and meniscal QNZ in vitro abnormality.

Methods: The present prospective study included thirty patients with knee pain, mechanical symptoms, and magnetic resonance imaging findings that were positive for a meniscal tear who chose arthroscopic partial meniscectomy after unsuccessful nonoperative management. Synovial fluid was aspirated at the time of surgery and was assayed for the fibronectin-aggrecan complex with use of a heterogeneous enzyme-linked immunosorbent assay (ELISA). The results were compared with knee aspirates from ten asymptomatic volunteers

with no pain who underwent magnetic resonance imaging of the knee.

Results: The mean optical density (and standard deviation) of the fibronectin-aggrecan complex was significantly greater in synovial fluid from knees undergoing arthroscopic surgery as compared with fluid from asymptomatic controls (13.29 +/- 8.48 compared with 0.03 +/- 0.09; p < 0.001). The mean age in the study group was significantly greater than in control group (46.0 +/- 12.6 compared with 38.5 +/- 6.0 years; p = 0.02), but controlling for age did not affect the results. Post hoc, an optical density cutoff value selleck inhibitor of 0.3 distinguished the study group from the control group with 100% accuracy.

Conclusions: A novel fibronectin-aggrecan complex is present in the synovial fluid of painful knees with meniscal abnormality. The fibronectin-aggrecan complex may prove to be useful as a clinical biomarker or therapeutic target. Further research is warranted to correlate functional outcome after surgery with the fibronectin-aggrecan complex and other cartilage biomarkers.”
“Interface formation between Ru and Si(001) has been studied by x-ray and ultraviolet photoemissions.