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1.
Philos Trans A Math Phys Eng Sci ; 380(2223): 20200383, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35341302

RESUMO

Factoring a wave function into marginal and conditional factors partitions the subsystem kinetic energy into two terms. The first depends solely on the marginal wave function, through its gauge-covariant derivative, while the second depends on the quantum metric of the conditional wave function over the manifold of marginal variables. We derive an identity for the rate of change of the second term. This article is part of the theme issue 'Chemistry without the Born-Oppenheimer approximation'.

2.
J Reprod Immunol ; 145: 103320, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33962140

RESUMO

Preeclampsia still represents a life-threatening pregnancy complication, associated with severe maternal and neonatal morbidity and mortality. Low-dose Aspirin is advised to avoid preeclampsia in high-risk pregnancies worldwide. As Aspirin does not cover all women at risk, the prescription raises questions concerning optimal target population, dosage, and onset of therapy. The aim of this study was to test platelet responsiveness on Aspirin by optical aggegrometry, to gain robust biochemically assessment data of Aspirin in an obstetric cohort. 248 women at high risk for development of preeclampsia were included in the study. Aspirin-prophylaxis was administered either in 100 mg (n = 229) or 150 mg (n = 90) daily. Dosing of 100 mg Aspirin was maintained if testing revealed a sufficient platelet inhibition. If platelet inhibition was insufficient, dosage was increased to 150 mg Aspirin and re-testing was advised. 91 patients (91/229 = 39.7%) presented a sufficient inhibitory Aspirin effect at a dosage of 100 mg, but in 138 patients LTA showed an inadequate Aspirin response (138/229 = 60.3%). In 19 women 150 mg Aspirin was administered as starting dose due to new recommendations. Of all women at 150 mg Aspirin 64 did not properly respond (35.4%). The overall rate of sufficient responding women regardless the Aspirin dose was 64.6%. This study demonstrates still an insufficient inhibition of platelet aggregation in about 1/3 of women even with a dosage of 150 mg Aspirin daily, who might potentially benefit from further increase. These data show, that there is a need for further research to allow a personalized approach for individualized Aspirin therapy, maximizing the preventive benefit for mother and child.


Assuntos
Aspirina/administração & dosagem , Plaquetas/efeitos dos fármacos , Inibidores da Agregação Plaquetária/administração & dosagem , Pré-Eclâmpsia/prevenção & controle , Adulto , Plaquetas/imunologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Agregação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/imunologia , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/imunologia , Gravidez , Gravidez de Alto Risco/sangue , Gravidez de Alto Risco/efeitos dos fármacos , Gravidez de Alto Risco/imunologia , Fatores de Risco
3.
Nano Lett ; 18(3): 1842-1848, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29424230

RESUMO

Laser pulses induce spin-selective charge flow that we show to generate dramatic changes in the magnetic structure of materials, including a switching of magnetic order from antiferromagnetic (AFM) to transient ferromagnetic (FM) in multisub-lattice systems. The microscopic mechanism underpinning this ultrafast switching of magnetic order is dominated by spin-selective charge transfer from one magnetic sublattice to another. Because this spin modulation is purely optical in nature (i.e., not mediated indirectly via the spin-orbit interaction) this is one of the fastest means of manipulating spin by light. We further demonstrate this mechanism to be universally applicable to AFM, FM, and ferri-magnets in both multilayer and bulk geometry and provide three rules that encapsulate early-time magnetization dynamics of multisub-lattice systems.

4.
Proc Natl Acad Sci U S A ; 114(11): 2801-2806, 2017 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-28265085

RESUMO

The fundamental energy gap of a periodic solid distinguishes insulators from metals and characterizes low-energy single-electron excitations. However, the gap in the band structure of the exact multiplicative Kohn-Sham (KS) potential substantially underestimates the fundamental gap, a major limitation of KS density-functional theory. Here, we give a simple proof of a theorem: In generalized KS theory (GKS), the band gap of an extended system equals the fundamental gap for the approximate functional if the GKS potential operator is continuous and the density change is delocalized when an electron or hole is added. Our theorem explains how GKS band gaps from metageneralized gradient approximations (meta-GGAs) and hybrid functionals can be more realistic than those from GGAs or even from the exact KS potential. The theorem also follows from earlier work. The band edges in the GKS one-electron spectrum are also related to measurable energies. A linear chain of hydrogen molecules, solid aluminum arsenide, and solid argon provide numerical illustrations.

5.
Adv Mater ; 29(10)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28092134

RESUMO

A conducting 2D electron gas (2DEG) is formed at the interface between epitaxial LaFeO3 layers >3 unit cells thick and the surface of SrTiO3 single crystals. The 2DEG is exquisitely sensitive to cation intermixing and oxygen nonstoichiometry. It is shown that the latter thus allows the controllable formation of the 2DEG via ionic liquid gating, thereby forming a nonvolatile switch.

7.
Sci Rep ; 6: 24411, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27076097

RESUMO

We predict a fast domain wall (DW) motion induced by a thermal gradient across a nanoscopic ferromagnetic stripe of MnBi. The driving mechanism is an exchange torque fueled by magnon accumulation at the DWs. Depending on the thickness of the sample, both hot-to-cold and cold-to-hot DW motion directions are possible. The finding unveils an energy efficient way to manipulate DWs as an essential element in magnetic information processing such as racetrack memory.

8.
Phys Rev Lett ; 114(4): 047002, 2015 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25679904

RESUMO

Inelastic tunneling spectroscopy of Pb islands on Cu(111) obtained by scanning tunneling microscopy below 1 K provides a direct access to the local Eliashberg function of the islands with high energy resolution. The Eliashberg function describes the electron-phonon interaction causing conventional superconductivity. The measured Eliashberg function strongly depends on the local thickness of the Pb nanostructures and shows a sharp maximum when quantum well states of the Pb islands come close to the Fermi energy. Ab initio calculations reveal that this is related to enhanced electron-phonon coupling at these thicknesses.


Assuntos
Elétrons , Chumbo/química , Modelos Teóricos , Fônons , Teoria Quântica , Cobre/química , Microscopia de Tunelamento/métodos
9.
Br J Cancer ; 108(4): 901-7, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23385728

RESUMO

BACKGROUND: The neutrophil-lymphocyte ratio (NLR) has been proposed as an indicator of systemic inflammatory response. Several studies suggest a negative impact of increased NLR for patient's survival in different types of cancer. However, previous findings from small-scale studies revealed conflicting results about its prognostic significance with regard to different clinical end points in non-metastatic renal cell carcinoma (RCC) patients. Therefore, the aim of our study was the validation of the prognostic significance of NLR in a large cohort of RCC patients. METHODS: Data from 678 consecutive non-metastatic clear cell RCC patients, operated between 2000 and 2010 at a single centre, were evaluated retrospectively. Cancer-specific, metastasis-free, as well as overall survival (OS) were assessed using the Kaplan-Meier method. To evaluate the independent prognostic significance of NLR, multivariate Cox regression models were applied for all three different end points. Influence of the NLR on the predictive accuracy of the Leibovich prognosis score was determined by Harrell's concordance index. RESULTS: Multivariate analysis identified increased NLR as an independent prognostic factor for overall (hazard ratio (HR)=1.59, 95% confidence interval (CI)=1.10-2.31, P=0.014), but not for cancer-specific (HR=1.59, 95% CI=0.84-2.99, P=0.148), nor for metastasis-free survival (HR=1.39, 95% CI=0.85-2.28, P=0.184). The estimated concordance index was 0.79 using the Leibovich risk score and 0.81 when NLR was added. CONCLUSION: Regarding patients' OS, an increased NLR represented an independent risk factor, which might reflect a higher risk for severe cardiovascular and other comorbidities. Adding the NLR to well-established prognostic models such as the Leibovich prognosis score might improve their predictive ability.


Assuntos
Carcinoma de Células Renais/sangue , Neoplasias Renais/sangue , Linfócitos/citologia , Neutrófilos/citologia , Idoso , Contagem de Células Sanguíneas , Carcinoma de Células Renais/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Renais/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Estudos Retrospectivos
10.
Br J Cancer ; 106(11): 1826-32, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22549179

RESUMO

BACKGROUND: MicroRNA-143 (miRNA-143) is frequently down-regulated in colorectal cancer (CRC) and may influence CRC cell proliferation, apoptosis and sensitivity to 5-fluorouracil. mRNA encoded by the KRAS oncogene has been identified as a target of miRNA-143. However, the prognostic significance of miRNA-143 expression and the ability to predict patient response to epidermal growth factor receptor (EGFR)-targeted agents have not yet been explored. METHODS: We examined 77 CRC patients who were identified by pyrosequencing to have wild-type KRAS and were subsequently treated with EGFR-targeted therapy with the monoclonal antibodies cetuximab or panitumumab. MicroRNA-143 expression was measured in CRC tissue and corresponding non-neoplastic colon tissue by RT-PCR and its expression level was correlated with clinico-pathological characteristics. Univariate and multivariate analyses were used to calculate cancer-specific survival (CSS). The progression-free survival (PFS) and objective response rates on EGFR-targeted therapy were also evaluated. RESULTS: Down-regulation of miRNA-143 was observed in 47 out of 77 (61%) tumours. Multivariate Cox regression analysis identified low levels of miRNA-143 expression as an independent prognostic factor with respect to CSS (hazard ratio=1.92, confidence interval=1.1-3.4, P=0.024). A significant difference was also observed with regard to PFS on EGFR-targeted therapy (P=0.031), but there were no significant differences with regard to the objective response rates. CONCLUSION: Our data indicate that miRNA-143 expression levels serve as an independent prognostic biomarker for CRC in KRAS wild-type patients. No role for miRNA-143 expression as a predictive biomarker for EGFR-targeted agents could be identified. Given its negative impact on CSS and PFS, miRNA-143 represents a novel prognosticator and a promising drug target for patients with CRC.


Assuntos
Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/biossíntese , Proteínas Proto-Oncogênicas/metabolismo , Proteínas ras/metabolismo , Adulto , Idoso , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Cetuximab , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Intervalo Livre de Doença , Regulação para Baixo , Receptores ErbB/metabolismo , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Panitumumabe , Prognóstico , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Estudos Retrospectivos , Proteínas ras/genética
11.
Scand J Rheumatol ; 40(6): 433-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21619489

RESUMO

OBJECTIVE: To investigate the mortality rate and possible early predictive factors of mortality after 19-23 years in a cohort of patients with rheumatoid arthritis (RA) followed prospectively from disease onset. PATIENTS AND METHODS: A community-based cohort of 183 patients (63% female) with RA and disease duration < 2 years was recruited 1985-1989. The patients were followed yearly from diagnosis until death or 31 December 2008. Mean age and mean duration of symptoms (range) at diagnosis were 52 (18-78) years and 11 (0-24) months, respectively. Death certificates were obtained from the Swedish Cause of Death Register and causes of death were coded by the International Classification of Diseases (ICD-10). Death rates of RA patients were compared to those of age- and sex-matched controls. Possible predictors of mortality were analysed using a Cox regression model. RESULTS: By 31 December 2008, 69 patients (37 women and 32 men) had died. The standardized mortality ratio (SMR) was 1.23 [95% confidence interval (CI) 0.97-1.55] and p < 0.09. Older age, male sex, smoking, and the presence of cardiovascular disease (CVD) at RA diagnosis were identified as early predictors of mortality. CVD was the most common cause of death (46%), followed by malignancies (29%) and infections (13%). RA was not stated as the direct cause of death in any patient and was mentioned among underlying causes in only 16/69 (23%) patients. CONCLUSION: Mortality rate after 19-23 years of disease duration in this cohort of patients with disease onset in the 1980s was not significantly increased compared to age- and sex-matched controls. No RA disease-related factor predicted mortality.


Assuntos
Artrite Reumatoide/mortalidade , Adolescente , Adulto , Idoso , Antirreumáticos/uso terapêutico , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/mortalidade , Causas de Morte , Estudos de Coortes , Doenças Transmissíveis/complicações , Doenças Transmissíveis/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Sistema de Registros , Características de Residência , Suécia/epidemiologia , Adulto Jovem
12.
Sci Am ; 295(3): 64-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16925037
13.
J Exp Psychol Learn Mem Cogn ; 27(5): 1223-37, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11550750

RESUMO

Syntactic and semantic processing of literal and idiomatic phrases were investigated with a priming procedure. In 3 experiments, participants named targets that were syntactically appropriate or inappropriate completions for semantically unrelated sentence contexts. Sentences ended with incomplete idioms (kick the...) and were biased for either a literal (ball) or an idiomatic (bucket) completion. Syntactically appropriate targets were named more quickly than inappropriate ones for both contextual biases, suggesting that syntactic analysis occurs for idioms. In a final experiment, targets were either concrete (expected) or abstract (unexpected) nouns. For literal sentences, the abstract targets were named more slowly than the concrete targets. In contrast, there was no concreteness effect for idiomatic sentences, suggesting that the literal meaning of the idiom is not processed. Overall, the results provide evidence for dissociation between syntactic and semantic processing.


Assuntos
Aprendizagem por Associação de Pares , Resolução de Problemas , Leitura , Semântica , Adulto , Feminino , Humanos , Julgamento , Masculino , Psicolinguística , Tempo de Reação
14.
Cogn Psychol ; 43(2): 83-128, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11527432

RESUMO

In English, words like scissors are grammatically plural but conceptually singular, while words like suds are both grammatically and conceptually plural. Words like army can be construed plurally, despite being grammatically singular. To explore whether and how congruence between grammatical and conceptual number affected the production of subject-verb number agreement in English, we elicited sentence completions for complex subject noun phrases like The advertisement for the scissors. In these phrases, singular subject nouns were followed by distractor words whose grammatical and conceptual numbers varied. The incidence of plural attraction (the use of plural verbs after plural distractors) increased only when distractors were grammatically plural, and revealed no influence from the distractors' number meanings. Companion experiments in Dutch offered converging support for this account and suggested that similar agreement processes operate in that language. The findings argue for a component of agreement that is sensitive primarily to the grammatical reflections of number. Together with other results, the evidence indicates that the implementation of agreement in languages like English and Dutch involves separable processes of number marking and number morphing, in which number meaning plays different parts.


Assuntos
Idioma , Psicolinguística , Análise de Variância , Humanos , Modelos Psicológicos , Países Baixos , Estados Unidos
15.
Psychol Sci ; 12(4): 282-6, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11476093

RESUMO

During an individual's normal interaction with the environment and other humans, visual and linguistic signals often coincide and can be integrated very quickly. This has been clearly demonstrated in recent eye tracking studies showing that visual perception constrains on-line comprehension of spoken language. In a modified visual search task, we found the inverse, that real-time language comprehension can also constrain visual perception. In standard visual search tasks, the number of distractors in the display strongly affects search time for a target defined by a conjunction of features, but not for a target defined by a single feature. However we found that when a conjunction target was identified by a spoken instruction presented concurrently with the visual display, the incremental processing of spoken language allowed the search process to proceed in a manner considerably less affected by the number of distractors. These results suggest that perceptual systems specializedfor language and for vision interact more fluidly than previously thought.


Assuntos
Linguística , Percepção Visual , Atenção , Humanos , Idioma
16.
J Psycholinguist Res ; 24(6): 409-36, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8531168

RESUMO

When listeners follow spoken instructions to manipulate real objects, their eye movements to the objects are closely time locked to the referring words. We review five experiments showing that this time-locked characteristic of eye movements provides a detailed profile of the processes that underlie real-time spoken language comprehension. Together, the first four experiments showed that listeners immediately integrated lexical, sublexical, and prosodic information in the spoken input with information from the visual context to reduce the set of referents to the intended one. The fifth experiment demonstrated that a visual referential context affected the initial structuring of the linguistic input, eliminating even strong syntactic preferences that result in clear garden paths when the referential context is introduced linguistically. We argue that context affected the earliest moments of language processing because it was highly accessible and relevant to the behavioral goals of the listener.


Assuntos
Movimentos Oculares , Percepção da Fala , Humanos , Testes de Linguagem , Processos Mentais
17.
Science ; 268(5217): 1632-4, 1995 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-7777863

RESUMO

Psycholinguists have commonly assumed that as a spoken linguistic message unfolds over time, it is initially structured by a syntactic processing module that is encapsulated from information provided by other perceptual and cognitive systems. To test the effects of relevant visual context on the rapid mental processes that accompany spoken language comprehension, eye movements were recorded with a head-mounted eye-tracking system while subjects followed instructions to manipulate real objects. Visual context influenced spoken word recognition and mediated syntactic processing, even during the earliest moments of language processing.


Assuntos
Cognição , Movimentos Oculares , Idioma , Percepção da Fala/fisiologia , Humanos
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