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1.
J Med Case Rep ; 17(1): 186, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37101309

RESUMEN

BACKGROUND: Chromosome 5p partial monosomy (5p-syndrome) and chromosome 6p partial trisomy are chromosomal abnormalities that result in a variety of symptoms, but liver dysfunction is not normally one of them. Alagille syndrome (OMIM #118450) is a multisystem disorder that is defined clinically by hepatic bile duct paucity and cholestasis, in association with cardiac, skeletal, and ophthalmologic manifestations, and characteristic facial features. Alagille syndrome is caused by mutations in JAG1 on chromosome 20 or NOTCH2 on chromosome 1. Here, we report a preterm infant with karyotype 46,XX,der(5)t(5,6)(p15.2;p22.3) and hepatic dysfunction, who was diagnosed as having incomplete Alagille syndrome. CASE PRESENTATION: The Japanese infant was diagnosed based on the cardiac abnormalities, ocular abnormalities, characteristic facial features, and liver pathological findings. Analysis of the JAG1 and NOTCH sequences failed to detect any mutations in these genes. CONCLUSIONS: These results suggest that, besides the genes that are known to be responsible for Alagille syndrome, other genetic mutations also may cause Alagille syndrome.


Asunto(s)
Síndrome de Alagille , Lactante , Humanos , Recién Nacido , Síndrome de Alagille/diagnóstico , Síndrome de Alagille/genética , Síndrome de Alagille/patología , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Recien Nacido Prematuro , Cariotipo
2.
Sci Rep ; 11(1): 18654, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34545160

RESUMEN

Band-gap engineering is one of the fundamental techniques in semiconductor technology and also applicable in next generation spintronics using the spin degree of freedom. To fully utilize the spintronic materials, it is essential to optimize the spin-dependent electronic structures in the operando conditions by applying magnetic and/or electric fields. Here we present an advanced spectroscopic technique to probe the spin-polarized electronic structures by using magnetic circular dichroism (MCD) in resonant inelastic soft X-ray scattering (RIXS) under an external magnetic field. Thanks to the spin-selective dipole-allowed transitions in RIXS-MCD, we have successfully demonstrated the direct evidence of the perfectly spin-polarized electronic structures for the prototypical halfmetallic Heusller alloy [Formula: see text]. RIXS-MCD is a promising tool to probe the spin-dependent carriers and band-gap induced in the buried magnetic layers in an element specific way under the operando conditions.

3.
J Neonatal Perinatal Med ; 13(1): 135-138, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32280067

RESUMEN

Placental chorioangioma (CA) is a benign placental tumor. No specific treatment is required for asymptomatic cases. We report a female infant born to a mother with giant placental CA. However fetal growth was normal and, fetal hydrops was not detected by ultrasound examination until delivery, she had hydrops, subgaleal hematoma, thrombocytopenia, hemolytic anemia, respiratory distress and circulatory failure after birth. She was successfully treated without any neurological sequelae. At 2 months of age, infantile hemangioma appeared in her lower lip. The present case suggested that giant placental CA might cause postnatal problems and be associated with the development of infantile hemangioma.


Asunto(s)
Anemia Hemolítica/etiología , Edema/etiología , Hemangioma/complicaciones , Neoplasias de los Labios/patología , Enfermedades Placentarias/patología , Complicaciones Neoplásicas del Embarazo/patología , Síndrome de Dificultad Respiratoria del Recién Nacido/etiología , Choque/etiología , Antagonistas Adrenérgicos beta/uso terapéutico , Anemia Hemolítica/terapia , Coagulación Intravascular Diseminada/etiología , Coagulación Intravascular Diseminada/terapia , Edema/terapia , Transfusión de Eritrocitos , Femenino , Hemangioma/diagnóstico por imagen , Hemangioma/tratamiento farmacológico , Hemangioma/patología , Hepatomegalia/etiología , Humanos , Hipoalbuminemia/etiología , Hipoalbuminemia/terapia , Recién Nacido , Neoplasias de los Labios/tratamiento farmacológico , Enfermedades Placentarias/diagnóstico por imagen , Plasma , Embarazo , Complicaciones Neoplásicas del Embarazo/diagnóstico por imagen , Propranolol/uso terapéutico , Púrpura/etiología , Púrpura/terapia , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Choque/terapia , Esplenomegalia/etiología , Trombocitopenia/etiología , Trombocitopenia/terapia , Carga Tumoral , Ultrasonografía Prenatal , Vasoconstrictores/uso terapéutico
4.
J Hosp Infect ; 104(2): 200-206, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31568809

RESUMEN

BACKGROUND: Infection control strategies are implemented in all neonatal intensive care units (NICUs); however, the details of the strategies seem to differ among institutions. The purpose of this survey was to investigate the current implementation status of infection control strategies in NICUs in Japan and to identify and recommend appropriate strategies for the prevention of outbreaks in neonatal units. METHODS: This survey documented the current implementation status and methods of selected infection prevention and control measures (active surveillance cultures and standard precaution) in 453 Japanese NICUs/neonatal units registered with the Japan Society of Perinatal and Neonatal Medicine, using questionnaires, in May 2018. FINDINGS: The response rate was 48.1% (level I institutions, 25.5%; level II, 55.9%; level III, 64.2%). Surveillance cultures were performed every week and targeted all bacteria in most units. The proportion of level III institutions that experienced outbreaks over the previous five years was significantly higher than that of level II institutions (55% vs 27%, P=0.0003). However, wearing a mask was less frequently recommended in level III institutions (55.7%) than in level II institutions (67.9%). Meticillin-resistant Staphylococcus aureus (MRSA) was the most frequently reported bacterial pathogen responsible for NICU outbreaks. CONCLUSION: Infection prevention and control practices regarding active pathogen surveillance cultures and the use of barrier precautions varied widely in Japanese neonatal units. National guidelines and evidence-based recommendations are needed to rationalize and standardize current infection prevention and control practices in neonatal units in Japan.


Asunto(s)
Infección Hospitalaria/prevención & control , Control de Infecciones/métodos , Control de Infecciones/estadística & datos numéricos , Unidades de Cuidado Intensivo Neonatal/estadística & datos numéricos , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Encuestas de Atención de la Salud , Humanos , Japón/epidemiología , Estudios Retrospectivos
5.
Nat Commun ; 10(1): 505, 2019 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-30705281

RESUMEN

Many properties of real materials can be modeled using ab initio methods within a single-particle picture. However, for an accurate theoretical treatment of excited states, it is necessary to describe electron-electron correlations including interactions with bosons: phonons, plasmons, or magnons. In this work, by comparing spin- and momentum-resolved photoemission spectroscopy measurements to many-body calculations carried out with a newly developed first-principles method, we show that a kink in the electronic band dispersion of a ferromagnetic material can occur at much deeper binding energies than expected (Eb = 1.5 eV). We demonstrate that the observed spectral signature reflects the formation of a many-body state that includes a photohole bound to a coherent superposition of renormalized spin-flip excitations. The existence of such a many-body state sheds new light on the physics of the electron-magnon interaction which is essential in fields such as spintronics and Fe-based superconductivity.

6.
J Perinatol ; 37(12): 1272-1277, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29022925

RESUMEN

OBJECTIVE: We evaluated cytomegalovirus (CMV) immunoglobulin M (IgM) titer in pregnant women with primary infection as a predictive factor for congenital infection. STUDY DESIGN: Maternal CMV antibody screening during the first trimester was conducted prospectively at 16 centers in Japan between September 2013 and 2015. Women with confirmed maternal primary infection underwent testing for fetal congenital infection, and we investigated the positive predictive value of CMV IgM titer levels for congenital infection in women with a low IgG avidity. RESULTS: We identified 6 (8.6%) cases of congenital infection among 70 pregnant women with positive/borderline IgG, positive IgM and IgG avidity index ⩽35.0% and 11 (39.3%) among 28 women with IgG and/or IgM seroconversion. IgM titer level ⩾6.00 index showed the highest positive predictive value (17.1%). CONCLUSION: High titer of CMV IgM during the first trimester in pregnant women with primary infection is a risk factor for congenital infection.


Asunto(s)
Anticuerpos Antivirales/orina , Infecciones por Citomegalovirus/sangre , Citomegalovirus/inmunología , Inmunoglobulina M/sangre , Complicaciones Infecciosas del Embarazo/sangre , Primer Trimestre del Embarazo/sangre , Adolescente , Adulto , Estudios de Casos y Controles , Infecciones por Citomegalovirus/congénito , Infecciones por Citomegalovirus/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Recién Nacido , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embarazo , Complicaciones Infecciosas del Embarazo/inmunología , Primer Trimestre del Embarazo/inmunología , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Adulto Joven
7.
J Phys Condens Matter ; 29(5): 055002, 2017 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-27911879

RESUMEN

An interface electron state at the junction between a three-dimensional topological insulator film, Bi2Se3, and a ferrimagnetic insulator film, Y3Fe5O12 (YIG), was investigated by measurements of angle-resolved photoelectron spectroscopy and x-ray absorption magnetic circular dichroism. The surface state of the Bi2Se3 film was directly observed and localized 3d spin states of the Fe3+ in the YIG film were confirmed. The proximity effect is likely described in terms of the exchange interaction between the localized Fe 3d electrons in the YIG film and delocalized electrons of the surface and bulk states in the Bi2Se3 film.

8.
Eur J Clin Microbiol Infect Dis ; 34(11): 2191-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26282790

RESUMEN

Surveillance of Streptococcus pneumoniae serotypes is important for the successful implementation of vaccination strategies to prevent the spread of invasive pneumococcal diseases. The standard method of serotyping of pneumococcal isolates is the phenotypic Neufeld test, which is cost- and labor-intensive. Recently, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been implemented as a rapid, simple and inexpensive method for identifying species. We evaluated the performance of MALDI-TOF MS for serotyping ten major serotypes of S. pneumoniae in Japan (serotypes 3, 6B, 15A, 15C, 19A, 19 F, 23A, 24 F, 35B and 38) using the Biotyper and ClinProTools. After optimizing the settings, we validated their serotyping performance for serotypes 3, 15A and 19A using a separate set of isolates that were not used in the creation of the classification algorithms. A total of 574 isolates of S. pneumoniae collected from Japanese nationwide surveillance studies were included. Of these, 407 isolates belonged to the ten major serotypes. Biotyper and ClinProTools correctly identified 77.9 % and 84.0 %, respectively, of the ten major serotype isolates. The validation analysis included a total of 113 isolates of the serotypes 3, 15A and 19A isolates. Biotyper and ClinProTools correctly identified 85.0 % and 69.9 % of the validation cohort isolates, respectively. MALDI-TOF MS has the potential to discriminate the ten major S. pneumoniae serotypes prevalent in Japan.


Asunto(s)
Serotipificación/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Streptococcus pneumoniae/química , Streptococcus pneumoniae/clasificación , Adolescente , Niño , Preescolar , Monitoreo Epidemiológico , Humanos , Lactante , Recién Nacido , Japón , Infecciones Neumocócicas/microbiología
9.
J Phys Condens Matter ; 25(41): 415601, 2013 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-24047823

RESUMEN

We have investigated the Ce 4f electronic states in the Ce-doped manganites Nd(0.45-x)Ce(x)Sr0.55MnO3 (NCSMO) by means of x-ray absorption spectroscopy (XAS) and hard x-ray photoelectron spectroscopy (HAXPES). The Ce 3d XAS shows that the Ce ions exist in the form of the Ce(3+) and Ce(4+) mixed-valent states, and we have found that the XAS spectral features change with temperature. The Ce 3d XAS and HAXPES spectra for NCSMO agree reasonably well with calculated results based on the single-impurity Anderson model, which takes into account the atomic multiplets and two valence bands. The estimated Ce bulk valence of Nd0.15Ce0.3Sr0.55MnO3 decreases from 3.44 to 3.30 with cooling.


Asunto(s)
Cesio/química , Modelos Químicos , Modelos Moleculares , Espectroscopía de Fotoelectrones , Espectroscopía de Absorción de Rayos X , Simulación por Computador , Conductividad Eléctrica , Ensayo de Materiales
10.
J Phys Condens Matter ; 25(1): 014007, 2013 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-23221164

RESUMEN

Temperature-dependent photoemission spectroscopy in Li(0.9)Mo(6)O(17) contributes to evidence for one-dimensional (1D) physics that is unusually robust. Three generic characteristics of the Luttinger liquid are observed: power law behavior of the k-integrated spectral function down to temperatures just above the superconducting transition, k-resolved lineshapes that show holon and spinon features, and quantum critical (QC) scaling in the lineshapes. Departures of the lineshapes and the scaling from expectations in the Tomonaga-Luttinger model can be partially described by a phenomenological momentum broadening that is presented and discussed. The possibility that some form of 1D physics obtains even down to the superconducting transition temperature is assessed.


Asunto(s)
Litio/química , Modelos Químicos , Modelos Moleculares , Espectroscopía de Fotoelectrones/métodos , Reología/métodos , Soluciones/química , Simulación por Computador , Conductividad Térmica
11.
Phys Rev Lett ; 110(24): 247601, 2013 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-25165961

RESUMEN

The interface between LaAlO(3) and SrTiO(3) hosts a two-dimensional electron system of itinerant carriers, although both oxides are band insulators. Interface ferromagnetism coexisting with superconductivity has been found and attributed to local moments. Experimentally, it has been established that Ti 3d electrons are confined to the interface. Using soft x-ray angle-resolved resonant photoelectron spectroscopy we have directly mapped the interface states in k space. Our data demonstrate a charge dichotomy. A mobile fraction contributes to Fermi surface sheets, whereas a localized portion at higher binding energies is tentatively attributed to electrons trapped by O vacancies in the SrTiO(3). While photovoltage effects in the polar LaAlO(3) layers cannot be excluded, the apparent absence of surface-related Fermi surface sheets could also be fully reconciled in a recently proposed electronic reconstruction picture where the built-in potential in the LaAlO(3) is compensated by surface O vacancies serving also as a charge reservoir.

12.
Rev Sci Instrum ; 81(10): 105111, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21034123

RESUMEN

The need for not only bulk sensitive but also extremely high resolution photoelectron spectroscopy for studying detailed electronic structures of strongly correlated electron systems is growing rapidly. Moreover, easy access to such a capability in one's own laboratory is desirable. Demonstrated here is the performance of a microwave excited rare gas (Xe, Kr, and Ar) lamp combined with ionic crystal filters (sapphire, CaF(2), and LiF), which can supply three strong lines near the photon energy of hnyu hν=8.4, 10.0, and 11.6 eV, with the hν resolution of better than 600 µeV for photoelectron spectroscopy. Its performance is demonstrated on some materials by means of both angle-integrated and angle-resolved measurements.

13.
J Indian Soc Pedod Prev Dent ; 27(2): 125-30, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19736508

RESUMEN

Traumatic lesions in primary teeth are frequent in pediatric patients and can cause problems both to the deciduous tooth and permanent successor. The impact strength on deciduous tooth can reach the growing permanent tooth, affecting its morphology, structure and position, or even hampering its proper development. This report describes an aesthetic-functional rehabilitation process in an 8 year 10 month old boy during a multidisciplinary treatment held at the Clinical Center of Dental Trauma in Primary Teeth of the Pediatric Dentistry of Dental College of University of São Paulo, Brazil. The patient presented bilateral posterior cross bite and the permanent left upper central incisor with ectopic eruption and enamel hypoplasy, preceded by avulsion of element 61, occurred when the patient was 1.6 years old. After diagnosis and treatment planning, a quick expansion of jaws was recommended with Hass-type rapid expander and orthodontic leveling with fixed braces. Due to the ectopic eruption, the gingival contour had been altered and hypertrophia was found, compromising aesthetics and avoiding local hygienic procedures. Gingivoplasty was carried out with high-intensity Diode Laser, followed by aesthetic restoration with compound resin. It was concluded that after deciduous teeth traumatism it is important that the patient undergoes clinic and radiographic assistance until the permanent teeth erupt so that an adequate multidisciplinary treatment can be offered to the patient.


Asunto(s)
Avulsión de Diente/complicaciones , Diente Primario/lesiones , Niño , Hipoplasia del Esmalte Dental/etiología , Hipoplasia del Esmalte Dental/terapia , Restauración Dental Permanente , Hipertrofia Gingival/etiología , Hipertrofia Gingival/cirugía , Gingivoplastia , Humanos , Masculino , Maloclusión/etiología , Maloclusión/terapia , Técnica de Expansión Palatina , Grupo de Atención al Paciente , Erupción Ectópica de Dientes/etiología , Erupción Ectópica de Dientes/terapia
14.
Phys Rev Lett ; 102(25): 257203, 2009 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-19659116

RESUMEN

The recently discovered giant magnetic anisotropy of single magnetic Co atoms raises the hope of magnetic storage in small clusters. We present a joint experimental and theoretical study of the magnetic anisotropy and the spin dynamics of Fe and Co atoms, dimers, and trimers on Pt(111). Giant anisotropies of individual atoms and clusters as well as lifetimes of the excited states were determined with inelastic scanning tunneling spectroscopy. The short lifetimes due to hybridization-induced electron-electron scattering oppose the magnetic stability provided by the magnetic anisotropies.

15.
Phys Rev Lett ; 98(15): 156402, 2007 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-17501367

RESUMEN

Sm-based heavy-fermion compound SmOs4Sb12 has been investigated by soft x-ray (hnu=1070-1600 eV) and hard x-ray (HX; hnu=7932 eV) spectroscopy. The HX photoemission spectroscopy clearly demonstrates that the strongly mixed-valence state and the heavy-fermion state coexist in the bulk. It is found that the Sm valence decreases below 100 K, indicating that the Kondo coherence develops with approaching the proposed Kondo temperature. Our theoretical analyses suggest that the origin of the coexistence in SmOs4Sb12 is the coincidence of two conditions, namely, (i) the energy difference between Sm divalent and trivalent states is very small and (ii) the hybridization between Sm 4f and conduction electrons is weak.

16.
Phys Rev Lett ; 98(3): 036405, 2007 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-17358704

RESUMEN

By virtue of the soft x-ray angle-resolved photoelectron spectroscopy, the three-dimensional bulk fermiology has been successfully performed for a strongly correlated Ce compound, ferromagnet CeRu2Ge2 in the paramagnetic phase. A clear difference of the Fermi surface topology from either band calculation or de Haas-van Alphen results in the ferromagnetic phase is observed and interpreted by considering the difference of the 4f contribution to the Fermi surfaces in the paramagnetic phase.

17.
Diabetologia ; 49(10): 2514-24, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16917760

RESUMEN

AIMS/HYPOTHESIS: Brain natriuretic peptide (BNP) is a potent vasorelaxing and natriuretic peptide that is secreted from the heart and has cardioprotective properties. We have previously generated hypotensive transgenic mice (BNP-Tg mice) that overproduce BNP in the liver, which is released into the circulation. Using this animal model, we successfully demonstrated the amelioration of renal injury after renal ablation and in proliferative glomerulonephritis. Glomerular hyperfiltration is an early haemodynamic derangement, representing one of the key mechanisms of the pathogenesis of diabetic nephropathy. Based on the suggested involvement of increased endogenous natriuretic peptides, the aim of this study was to investigate their role in the development and progression of diabetic nephropathy. MATERIALS AND METHODS: We evaluated the progression of renal injury and fibrogenesis in BNP-Tg mice with diabetes induced by streptozotocin. We also investigated the effect of BNP on high glucose-induced signalling abnormalities in mesangial cells. RESULTS: After induction of diabetes, control mice exhibited progressively increased urinary albumin excretion with impaired renal function, whereas these changes were significantly ameliorated in BNP-Tg mice. Notably, diabetic BNP-Tg mice revealed minimal mesangial fibrogenesis with virtually no glomerular hypertrophy. Glomerular upregulation of extracellular signal-regulated kinase, TGF-beta and extracellular matrix proteins was also significantly inhibited in diabetic BNP-Tg mice. In cultured mesangial cells, activation of the above cascade under high glucose was abrogated by the addition of BNP. CONCLUSIONS/INTERPRETATION: Chronic excess of BNP prevents glomerular injury in the setting of diabetes, suggesting that renoprotective effects of natriuretic peptides may be therapeutically applicable in preventing the progression of diabetic nephropathy.


Asunto(s)
Nefropatías Diabéticas/prevención & control , Péptido Natriurético Encefálico/genética , Animales , Nefropatías Diabéticas/patología , Progresión de la Enfermedad , Mesangio Glomerular/fisiología , Glomerulonefritis/patología , Glomerulonefritis/prevención & control , Ratones , Ratones Transgénicos , Péptido Natriurético Encefálico/fisiología , Regiones Promotoras Genéticas , ARN/genética , ARN/aislamiento & purificación , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley
18.
Phys Rev Lett ; 96(14): 147203, 2006 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-16712116

RESUMEN

Specific-heat experiments on single crystals of the S = 1 quasi-one-dimensional bond-alternating antiferromagnet Ni(C9H24N4)(NO2)ClO2 (NTENP) have been performed in magnetic fields applied both parallel and perpendicular to the spin chains. We have found for the parallel field configuration that the magnetic specific heat (C(mag)) is proportional to temperature (T) above a critical field H(c), at which the energy gap vanishes, in a temperature region above that of the long-range ordered state. The ratio C(mag)/T increases as the magnetic field approaches H(c) from above. The data are in good quantitative agreement with the prediction of the c= 1 conformal field theory in conjunction with the velocity of the excitations calculated by a numerical diagonalization, providing conclusive evidence for a Tomonaga-Luttinger liquid.

19.
Phys Rev Lett ; 95(20): 207205, 2005 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-16384095

RESUMEN

We have successfully fabricated a novel type of high-density spiral terraces on Cr(001) films. The influence of nanoscale spiral terraces on layered antiferromagnetic ordering of Cr(001) films has been studied at room temperature by direct imaging of both topographic and magnetic structures using spin-polarized scanning tunneling spectroscopy. Spin frustration and asymmetric magnetic ordering due to dense spiral terraces are observed. Sizable modification of the layered antiferromagnetic order is found to be originating from the topological asymmetry as confirmed by the continuum micromagnetic simulation.

20.
Phys Rev Lett ; 94(14): 147202, 2005 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15904100

RESUMEN

We have investigated the chemical distributions and the local electronic structure of potential diluted magnetic semiconductor Ge0.94Mn0.06 single crystals using scanning photoelectron microscopy (SPEM), x-ray absorption spectroscopy (XAS), and photoemission spectroscopy (PES). The SPEM image shows the stripe-shaped microstructures, which arise from the chemical phase separation between the Mn-rich and Mn-depleted phases. The Mn 2p XAS shows that the Mn ions in the Mn-rich region are in the divalent high-spin Mn2+ states but that they do not form metallic Mn clusters. The Mn 3d PES spectrum exhibits a peak centered at approximately 4 eV below E(F) and the negligible spectral weight near E(F). This study suggests that the observed ferromagnetism in Ge1-xMnx arises from the phase-separated Mn-rich phase.

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