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1.
Nat Commun ; 13(1): 6129, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253344

RESUMO

Effective models focused on pertinent low-energy degrees of freedom have substantially contributed to our qualitative understanding of quantum materials. An iconic example, the Kondo model, was key to demonstrating that the rich phase diagrams of correlated metals originate from the interplay of localized and itinerant electrons. Modern electronic structure calculations suggest that to achieve quantitative material-specific models, accurate consideration of the crystal field and spin-orbit interactions is imperative. This poses the question of how local high-energy degrees of freedom become incorporated into a collective electronic state. Here, we use resonant inelastic x-ray scattering (RIXS) on CePd3 to clarify the fate of all relevant energy scales. We find that even spin-orbit excited states acquire pronounced momentum-dependence at low temperature-the telltale sign of hybridization with the underlying metallic state. Our results demonstrate how localized electronic degrees of freedom endow correlated metals with new properties, which is critical for a microscopic understanding of superconducting, electronic nematic, and topological states.

2.
Phys Rev Lett ; 127(7): 076402, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34459638

RESUMO

The anisotropic optical response of the layered, nodal-line semimetal ZrSiS at ambient and high pressure is investigated by frequency-dependent reflectivity measurements for the polarization along and perpendicular to the layers. The highly anisotropic optical conductivity is in very good agreement with results from density-functional theory calculations and confirms the anisotropic character of ZrSiS. Whereas the in-plane optical conductivity shows only modest pressure-induced changes, we found strong effects on the out-of-plane optical conductivity spectrum of ZrSiS, with the appearance of two prominent excitations. These pronounced pressure-induced effects can neither be attributed to a structural phase transition according to our single-crystal x-ray diffraction measurements, nor can they be explained by electronic correlation and electron-hole pairing effects, as revealed by theoretical calculations. Our findings are discussed in the context of the recently proposed excitonic insulator phase in ZrSiS.

3.
BJOG ; 126(7): 901-905, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30758126

RESUMO

OBJECTIVES: To evaluate the association of a history of threatened preterm labour (TPL) followed by term delivery with the risk of spontaneous preterm delivery (PTD) in subsequent pregnancy. DESIGN: Population-based cohort study. SETTING: Data of the National Health Insurance Claims Database and a national health-screening programme for infants and children in South Korea. POPULATION: Women who had their first singleton delivery in 2010 and a subsequent second singleton delivery between 2011 and 2015. METHODS: Multivariable analysis adjusting for maternal age and interval between first and second deliveries was used to assess the risk of PTD based on PTD, TPL followed by term delivery, and term delivery in the first pregnancy. MAIN OUTCOME MEASURES: The risk of PTD during the second pregnancy. RESULTS: This study included 115 629 women with two consecutive deliveries during the study period. Spontaneous PTD rates in the second pregnancy were 7.71, 2.22 and 1.02% in women with PTD, TPL followed by term delivery, and term delivery in the first pregnancy, respectively. Threatened preterm labour followed by term delivery in the first pregnancy was associated with increased risk of PTD in the subsequent pregnancy after adjustment for potential confounding factors (adjusted odds ratio 2.21; 95% CI 1.76-2.78). CONCLUSION: Although women with a history of TPL followed by term delivery had a lower risk of PTD during a subsequent pregnancy compared with those with history of previous PTD, they still had a significantly increased risk of PTD compared with those who delivered at term without TPL. TWEETABLE ABSTRACT: The history of threatened preterm labour followed by term delivery is related to increased risk of subsequent spontaneous preterm delivery.


Assuntos
Ameaça de Aborto/epidemiologia , Nascimento Prematuro/epidemiologia , Nascimento a Termo/fisiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Idade Materna , Gravidez , Recidiva , República da Coreia/epidemiologia , Fatores de Risco
4.
J Chem Phys ; 149(1): 014903, 2018 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-29981556

RESUMO

For highly non-uniformly flowing fluids, there are contributions to the stress related to spatial variations of the shear rate, which are commonly referred to as non-local stresses. The standard expression for the shear stress, which states that the shear stress is proportional to the shear rate, is based on a formal expansion of the stress tensor with respect to spatial gradients in the flow velocity up to leading order. Such a leading order expansion is not able to describe fluids with very rapid spatial variations of the shear rate, like in micro-fluidics devices and in shear-banding suspensions. Spatial derivatives of the shear rate then significantly contribute to the stress. Such non-local stresses have so far been introduced on a phenomenological level. In particular, a formal gradient expansion of the stress tensor beyond the above mentioned leading order contribution leads to a phenomenological formulation of non-local stresses in terms of the so-called "shear-curvature viscosity". We derive an expression for the shear-curvature viscosity for dilute suspensions of spherical colloids and propose an effective-medium approach to extend this result to concentrated suspensions. The validity of the effective-medium prediction is confirmed by Brownian dynamics simulations on highly non-uniformly flowing fluids.

5.
Clin Exp Obstet Gynecol ; 44(2): 264-267, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29746035

RESUMO

PURPOSE OF INVESTIGATION: The authors aimed to determine the relationship between meteorological variables and hypertension in pregnancy by using data from a national weather database. MATERIALS AND METHODS: For this population-based observational study, the database of the Korea National Health Insurance (KNHI) Claims of the Health Insurance Review and Assessment Service (HIRA) and Korea Meteorological Administration was used. The 48,275 women with preeclampsia among 2,495,383 women who gave birth were included. Monthly meteorological factors and preeclampsia prevalence for five years were statistically analyzed. RESULTS: Among temperature, relative humidity, sunlight duration, and rainfall, only relative humidity had a significant inverse correlation with the preeclampsia prevalence (p < 0.001). The other meteorological factors were not associated with preeclampsia. CONCLUSION: Relative humidity may be a significant factor for of the development of preeclampsia. Further monitoring of weather parameters during the entire pregnancy period may be the best method for verifying the present results in the development of preeclampsia.


Assuntos
Umidade/efeitos adversos , Pré-Eclâmpsia , Adulto , Bases de Dados Factuais , Feminino , Humanos , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Conceitos Meteorológicos , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/fisiopatologia , Gravidez , Prevalência , República da Coreia/epidemiologia , Fatores de Risco , Estatística como Assunto
6.
Environ Sci Process Impacts ; 19(1): 59-64, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28002504

RESUMO

Most particles in the rail subway environment are sub-micron sized ferruginous flakes and splinters generated mechanically by frictional wear of brake pads, wheels and rails. To better understand the mechanisms of formation and the alteration processes affecting inhalable particles in subways, PM samples (1-2.5 µm and 2.5-10 µm) were collected in the Barcelona Metro and then studied under a scanning electron microscope. Most particles in these samples are hematitic (up to 88%), with relatively minor amounts of mineral matter (up to 9%) and sulphates (up to 5%). Detailed microscopy (using back scattered and TEM-DRX imaging) reveals how many of the metallic particles comprise the metallic Fe nucleus surrounded by hematite (Fe2O3) and a coating of sulphate and chloride salts mixed with mineral matter (including Ca-carbonates, clay minerals and quartz). These observations record the emission of fine to ultrafine FePM by frictional wear at elevated temperatures that promote rapid partial (or complete) oxidation of the native metal. Water condensing on the PM surface during cooling leads to the adsorption of inorganic mineral particles that coat the iron oxide. The distinctively layered polymineralic structure that results from these processes is peculiar to particles generated in the subway environment and very different from PM typically inhaled outdoors.


Assuntos
Poluentes Atmosféricos/química , Poluição do Ar em Ambientes Fechados/análise , Metais/química , Material Particulado/química , Ferrovias , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Compostos Férricos/análise , Compostos Férricos/química , Fricção , Ferro/análise , Ferro/química , Metais/análise , Tamanho da Partícula , Material Particulado/análise , Espanha
7.
J Phys Condens Matter ; 28(5): 056005, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26760118

RESUMO

High pressure x-ray diffraction measurements on perovskite RMnO3 (R = Dy, Ho and Lu) reveal that varying structural changes occur for different R ions. Large lattice changes (orthorhombic strain) occur in DyMnO3 and HoMnO3 while the Jahn-Teller (JT) distortion remains stable. Conversely, in the small R-ion system LuMnO3, Mn-O bond distortions are observed between 4 and 8 GPa with a broad minimum in the JT distortion. High pressure infrared measurements indicate that a phonon near 390 cm(-1) corresponding to the complex motion of the Mn and O ions changes anomalously for LuMnO3. It softens in the 4-8 GPa region, which is consistent with the structural change in Mn-O bonds and then hardens at higher pressures. By contrast, the phonons continuously harden with increasing pressure for DyMnO3 and HoMnO3. Density functional theory methods show that E-phase LuMnO3 is the most stable phase up to the 10 GPa pressure examined. Simulations indicate that the distinct structural change under pressure in LuMnO3 can possibly be used to optimize the electric polarization by pressure/strain.

10.
J Phys Condens Matter ; 26(49): 495402, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25396338

RESUMO

Detailed structural measurements on multiple length scales were conducted on a new perovskite phase of ScMnO3, and on orthorhombic LuMnO3 as a benchmark. Complementary density functional theory (DFT) calculations were carried out, and predict that ScMnO3 possesses E-phase magnetic order at low temperature with displacements of the Mn sites (relative to the high temperature state) of ∼0.07 Å, compared to ∼0.04 Å predicted for LuMnO3. However, detailed local, intermediate and long-range structural measurements by x-ray pair distribution function analysis, single crystal x-ray diffraction and x-ray absorption spectroscopy, find no local or long-range distortions on crossing into the low temperature E-phase of the magnetically ordered state. The measurements place upper limits on any structural changes to be at most one order of magnitude lower than DFT predictions and suggest that this theoretical approach does not properly account for the spin-lattice coupling in these oxides and may possibly predict the incorrect magnetic order at low temperatures. The results suggest that the electronic contribution to the electrical polarization dominates and should be more accurately treated in theoretical models.

11.
J Obstet Gynaecol ; 32(4): 362-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22519482

RESUMO

Anterior vaginal wall prolapse is the most common type of pelvic organ prolapse. Vaginal wall samples were obtained from women with (n =12) and without (n =12) anterior vaginal wall prolapse. No reports have been published on the content of fibulin-3 in the vaginal walls of patients with prolapse; thus, we compared the expression of fibulin-3 in the vaginal walls of women with and without anterior vaginal wall prolapse. RT-PCR was performed to measure mRNA expression and the expression of protein was assessed by immunohistochemistry. Statistical analysis was performed to determine differences between the two groups of women. Age, parity and menopausal status did not differ between women with and without prolapse. The expressions of fibulin-3 mRNA and protein were not different between the prolapse and no prolapse groups. It is unlikely that abnormal expression of fibulin-3 has a major role in the pathogenesis of anterior vaginal wall prolapse.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Prolapso Uterino/metabolismo , Vagina/metabolismo , Adulto , Proteínas da Matriz Extracelular/genética , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Bioresour Technol ; 102(3): 2462-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21109429

RESUMO

Potential use of the municipal sludge ozonolysate as a carbon source was examined for phosphorus removal from low strength wastewater in a modified intermittently decanted extended aeration (IDEA) process. At ozone dosage of 0.2 g O(3)/g solids, readily biodegradable COD accounted for about 36% of COD from sludge ozonolysate. The denitrification potential of ozonolysate as a carbon source was comparable to that of acetate. Although, the first order constant for phosphorus release with the ozonolysate was half that of acetate, it was much higher than that of wastewater. Continuous operation of the modified IDEA process showed that the removals of nitrogen and phosphorus were simultaneously enhanced by addition of the ozonolysate. Phosphorus release was significantly induced after complete denitrification indicating that phosphorus release was strongly depended on nitrate concentration. Effectiveness of the ozonolysate as a carbon source for EBPR was also confirmed in a track study of the modified IDEA.


Assuntos
Bactérias Anaeróbias/metabolismo , Ozônio/metabolismo , Fósforo/isolamento & purificação , Fósforo/metabolismo , Esgotos/microbiologia , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos
14.
Water Sci Technol ; 61(5): 1183-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20220240

RESUMO

Hydrotalcite (HTAL-Cl), an inorganic anion exchanger, is of use as an adsorbent for the removal of arsenate (As(V)) in water systems. The adsorption properties of HTAL-Cl for As(V) and the effects of co-existing anions on the As(V) removal performance were investigated in this work. Under the conditions of pH>or=4, the adsorption capacity for As(V) gradually decreased with an increase of pH, but As(V) was removed effectively within the range of pH = 5-8. Co-existing anions interfered As(V) removal, and the effect decreased in the order of HPO(4)(2-) > HCO(3)(-) > SO(4)(2-) > Cl(-). In binary solute systems containing phosphate and As(V), the maximum adsorption capacity of HTAL-Cl was 0.95 mmol g(-1) for phosphate and 0.65 mmol g(-1) for As(V): the total of these values corresponded to the maximum adsorption capacity for As(V) in single solute systems. The adsorption isotherms in these binary solute systems were approximated by the following modified Langmuir equations:As(V): q(As) = 18.7 radicalC(As)/(1 + 21.5 radicalC(P) + 12.8 radicalC(As)), phosphate : q(P) = 33.1 radicalC(P)/(1 + 21.5 radicalC(P) + 12.8 radicalC(As)). The column adsorption experiments showed that the adsorbed As(V) was released by the phosphate adsorption, because phosphate was adsorbed more strongly on HTAL-CL than As(V).


Assuntos
Hidróxido de Alumínio/química , Arseniatos/isolamento & purificação , Hidróxido de Magnésio/química , Purificação da Água/métodos , Adsorção , Ânions , Arseniatos/química , Arsênio/química , Concentração de Íons de Hidrogênio , Resinas de Troca Iônica/química , Modelos Teóricos , Fosfatos/química , Pós , Propriedades de Superfície , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
15.
Bone Marrow Transplant ; 45(6): 1038-46, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19881555

RESUMO

Post transplant infusion of donor-type natural killer (NK) cells has been shown to have an anti-leukemia-enhancing effect without evoking GVHD in murine hematopoietic cell transplantation (HCT) models. Here, we tested 14 patients (age, 23-65 years), 12 with acute leukemia and 2 with myelodysplastic syndrome, who underwent HLA-mismatched HCT and subsequently received donor NK cell infusions. Cell donors (age, 16-51 years), comprising seven siblings, five offspring, and two mothers of the patients, underwent growth factor-mobilized leukapheresis for 3-5 days. Cells collected on the first 2-4 days were used for HCT, whereas those collected on the last day were CD34 selected by magnetic-activated cell sorting (median, 2.22 x 10(6) cells/kg; range, 0.29-5.66). Donor NK cells were generated from the CD34(+) cells by ex vivo cell culture over a 6-week period (median, 9.28 x 10(6) cells/kg; range, 0.33-24.50; CD122/CD56(+) 64%; CD3(+) 1.0%; and viability 88%). There were no signs of acute toxicity in patients infused with these cells 6-7 weeks post transplant. Overall, one and five patients developed acute and chronic GVHD during post transplant period, respectively. These results showed that clinical-grade donor NK cell production from CD34(+) cells is feasible.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/citologia , Células Matadoras Naturais/transplante , Transfusão de Linfócitos/métodos , Adulto , Antígenos CD34 , Técnicas de Cultura de Células , Estudos de Viabilidade , Feminino , Doença Enxerto-Hospedeiro/prevenção & controle , Antígenos HLA , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Células Matadoras Naturais/citologia , Leucemia/terapia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/terapia , Doadores de Tecidos , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
16.
Water Sci Technol ; 58(5): 1031-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18824801

RESUMO

One of the objectives of this study was to delineate the effect of nitrate on diethyl phthalate (DEP) oxidation by conducting a bench-scale ultraviolet (UV)/H2O2 and O3/H2O2 operations as suggested in a previous study. We also aim to investigate DEP oxidation at various UV doses and H2O2 concentrations by performing a pilot-scale advanced oxidation processes (AOP) system, into which a portion of the effluent from a pilot-scale membrane bioreactor (MBR) plant was pumped. In the bench-scale AOP operation, the O3 oxidation alone as well as the UV irradiation without H2O2 addition could be among the desirable alternatives for the efficient removal of DEP dissolved in aqueous solutions at a low DEP concentration range of 85+/-15 microg/L. The adverse effect in the UV/H2O2 process was significantly greater than that in the UV oxidation alone, and its oxidation was almost halved by the nitrate. However, the nitrate clearly enhanced the DEP oxidation in the O3 oxidation and O3/H2O2 process. Especially, the addition of nitrate almost doubled the DEP oxidation efficiency in the O3/H2O2 process. The series of pilot-scale AOP operations confirmed that about 30-50% of DEP dissolved in the treated MBR effluent streams was, at least, oxidized by the O3 oxidation alone as well as the UV irradiation without H2O2 addition. The UV photolysis of H2O2 was most effective for DEP degradation with an H2O2 concentration of 40 mg/L at a UV dose of 500 mJ/cm2.


Assuntos
Peróxido de Hidrogênio/química , Nitratos/química , Ácidos Ftálicos/química , Reatores Biológicos , Oxirredução/efeitos da radiação , Raios Ultravioleta , Purificação da Água/instrumentação , Purificação da Água/métodos
17.
Artigo em Inglês | MEDLINE | ID: mdl-18821242

RESUMO

Ozonation was applied to wastewater sludge for reduction and stabilization. Ozone was found to be very effective at reducing sludge and producing a useful carbon source. An ozone dose of 0.3 g/gDS fulfilled the criteria for the disinfection of class A type biosolids. The sludge treated with 0.5 gO(3)/gDS produced no hydrogen sulfide for a month at 29 degrees C. Ozonation resulted in low pH conditions, which might facilitate the mobilization of heavy metals from sludge. The results of a geotechnical investigation proved that the residuals of ozone-treated sludge did not meet the required properties required for landfill cover without the addition of quick lime.


Assuntos
Desinfecção/métodos , Ozônio/química , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Carbono/análise , Carbono/química , Relação Dose-Resposta a Droga , Sulfeto de Hidrogênio/análise , Sulfeto de Hidrogênio/química , Concentração de Íons de Hidrogênio , Coreia (Geográfico) , Metais Pesados/análise , Metais Pesados/química , Ozônio/farmacologia , Temperatura , Fatores de Tempo
18.
Environ Technol ; 29(2): 199-206, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18613618

RESUMO

Fatty acid methyl ester (FAME) technology was evaluated as a monitoring tool for quantification of Gordonia amarae in activated sludge systems. The fatty acid, 19:1 alcohol, which was identified as a unique fatty acid in G. amarae was not only confirmed to be present in foaming plant samples, but the quantity of the signature peak correlated closely with the degree of foaming. Foaming potential experiment provided a range of critical foaming levels that corresponded to G. amarae population. This range of critical Gordonia levels was correlated to the threshold signature FAME amount. Six full-scale wastewater treatment plants were selected based on a survey to participate in our full-scale study to evaluate the potential application of the FAME technique as the Gordonia monitoring tool. Greater amounts of signature FAME were extracted from the mixed liquor samples obtained from treatment plants experiencing Gordonia foaming problems. The amounts of signature FAME correlated well with the conventional filamentous counting technique. These results demonstrated that the relative abundance of the signature FAMEs can be used to quantitatively monitor the abundance of foam-causing microorganism in activated sludge.


Assuntos
Álcoois/análise , Ésteres/química , Ácidos Graxos/metabolismo , Esgotos , Reatores Biológicos , Cromatografia Gasosa , Desenho de Equipamento , Bactéria Gordonia/genética , Bactéria Gordonia/metabolismo , Oxigênio/química , Fatores de Tempo , Eliminação de Resíduos Líquidos/métodos , Microbiologia da Água , Purificação da Água
19.
Phys Rev Lett ; 98(12): 126407, 2007 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-17501144

RESUMO

The nature of the emergent phase near a putative quantum critical point in the bilayer ruthenate Sr3Ru2O7 has been a recent subject of intensive research. It has been suggested that this phase may possess electronic nematic order (ENO). In this work, we investigate the possibility of nematic domain formation in the emergent phase, using a phenomenological model of electrons with ENO and its coupling to lattice degrees of freedom. The resistivity due to the scattering off the domain walls is shown to closely follow the ENO parameter. Our results provide qualitative explanations for the dependence of the resistivity on external magnetic fields in Sr3Ru2O7.

20.
Water Sci Technol ; 53(7): 185-90, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16752780

RESUMO

A novel filtration process with synthetic permeable media was investigated for secondary effluent reclamation. Polyurethane was chosen as the filter medium among three tested media. Compressibility and up-flow velocity were changed to determine the optimum operation for the system. An equation was introduced to express the relationship between the removal efficiency and up-flow velocity. In a pilot study, the synthetic medium filtration with compression showed very stable effluent quality without clogging trouble, though the system operated with three times higher filtration rate and much longer backwashing interval than conventional systems.


Assuntos
Filtração/métodos , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Poliuretanos
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