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The microscopic structure of the low-energy electric dipole response, commonly denoted as pygmy dipole resonance (PDR), was studied for ^{120}Sn in a ^{119}Sn(d,pγ)^{120}Sn experiment. Unprecedented access to the single-particle structure of excited 1^{-} states below and around the neutron-separation threshold was obtained by comparing experimental data to predictions from a novel theoretical approach. The novel approach combines detailed structure input from energy-density functional plus quasiparticle-phonon model theory with reaction theory to obtain a consistent description of both the structure and reaction aspects of the process. The presented results show that the understanding of one-particle-one-hole structures of the 1^{-} states in the PDR region is crucial to reliably predict properties of the PDR and its contribution to nucleosynthesis processes.
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New experimental data on the neutron single-particle character of the Pygmy Dipole Resonance (PDR) in ^{208}Pb are presented. They were obtained from (d,p) and resonant proton scattering experiments performed at the Q3D spectrograph of the Maier-Leibnitz Laboratory in Garching, Germany. The new data are compared to the large suite of complementary, experimental data available for ^{208}Pb and establish (d,p) as an additional, valuable, experimental probe to study the PDR and its collectivity. Besides the single-particle character of the states, different features of the strength distributions are discussed and compared to large-scale shell model (LSSM) and energy-density functional plus quasiparticle-phonon model theoretical approaches to elucidate the microscopic structure of the PDR in ^{208}Pb.
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Monolayer FeSe exhibits the highest transition temperature among the iron based superconductors and appears to be fully gapped, seemingly consistent with s-wave superconductivity. Here, we develop a theory for the superconductivity based on coupling to fluctuations of checkerboard magnetic order (which has the same translation symmetry as the lattice). The electronic states are described by a symmetry based k·p-like theory and naturally account for the states observed by angle resolved photoemission spectroscopy. We show that a prediction of this theory is that the resultant superconducting state is a fully gapped, nodeless, d-wave state. This state, which would usually have nodes, stays nodeless because, as seen experimentally, the relevant spin-orbit coupling has an energy scale smaller than the superconducting gap.
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We theoretically consider the superconductivity of the topological half-Heusler semimetals YPtBi and LuPtBi. We show that pairing occurs between j=3/2 fermion states, which leads to qualitative differences from the conventional theory of pairing between j=1/2 states. In particular, this permits Cooper pairs with quintet or septet total angular momentum, in addition to the usual singlet and triplet states. Purely on-site interactions can generate s-wave quintet time-reversal symmetry-breaking states with topologically nontrivial point or line nodes. These local s-wave quintet pairs reveal themselves as d-wave states in momentum space. Furthermore, due to the broken inversion symmetry in these materials, the s-wave singlet state can mix with a p-wave septet state, again with topologically stable line nodes. Our analysis lays the foundation for understanding the unconventional superconductivity of the half-Heuslers.
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The aim of this study was to investigate the effect of puerperal uterine disease on histopathologic findings and gene expression of proinflammatory cytokines in the endometrium of postpuerperal dairy cows; 49 lactating Holstein-Friesian cows were divided into two groups, one without (UD-; n = 29) and one with uterine disease (UD+; n = 21), defined as retained fetal membranes and/or clinical metritis. General clinical examination, vaginoscopy, transrectal palpation, and transrectal B-mode sonography were conducted on days 8, 11, 18, and 25 and then every 10 days until Day 65 (Day 0 = day of calving). The first endometrial sampling (ES1; swab and biopsy) was done during estrus around Day 42 and the second endometrial sampling (ES2) during the estrus after synchronization (cloprostenol between days 55 and 60 and GnRH 2 days later). The prevalence of histopathologic evidence of endometritis, according to the categories used here, and positive bacteriologic cultures was not affected by group (P > 0.05), but cows with uterine disease had a higher prevalence of chronic purulent endometritis (ES1; P = 0.07) and angiosclerosis (ES2; P ≤ 0.05) than healthy cows. Endometrial gene expression of IL1α (ES2), IL1ß (ES2), and TNFα (ES1 and ES2) was higher (P ≤ 0.05) in the UD+ group than in the UD- group. In conclusion, puerperal uterine disease had an effect on histopathologic parameters and on gene expression of proinflammatory cytokines in the endometrium of postpuerperal cows, indicating impaired clearance of uterine inflammation in cows with puerperal uterine disease.
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Doenças dos Bovinos/metabolismo , Citocinas/metabolismo , Endométrio/metabolismo , Regulação da Expressão Gênica/fisiologia , Transtornos Puerperais/veterinária , RNA Mensageiro/metabolismo , Animais , Bovinos , Doenças dos Bovinos/patologia , Citocinas/genética , Feminino , Transtornos Puerperais/metabolismo , Transtornos Puerperais/patologia , RNA Mensageiro/genéticaRESUMO
High-resolution angle-resolved photoelectron spectroscopy is used to examine the electronic band structure of FeTe_{0.5}Se_{0.5} near the Brillouin zone center. A consistent separation of the α_{1} and α_{2} bands is observed with little k_{z} dependence of the α_{1} band. First-principles calculations for bulk and thin films demonstrate that the antiferromagnetic coupling between the Fe atoms and hybridization-induced spin-orbit effects lifts the degeneracy of the Fe d_{xz} and d_{yz} orbitals at the zone center leading to orbital ordering. These experimental and computational results provide a natural microscopic basis for the nematicity observed in the Fe-based superconductors.
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The objective of this study was to investigate the effect of time of first postpartum ovulation on endometrial inflammation in dairy cows with and without uterine disease during the early puerperal period. Transvaginal follicular puncture (FP) was carried out to suppress postpartum ovulation and formation of a CL until Day 42. Fifty-three lactating Holstein Friesian cows were divided into four groups on the basis of presence (UD+) or absence (UD-) of uterine disease, which was defined as retained fetal membranes and/or metritis, and whether FP had (FP+) or had not been (FP-) carried out. This resulted in the following groups: UD-FP- (n = 15), UD-FP+ (n = 13), UD+FP- (n = 13), and UD+FP+ (n = 12). Cloprostenol was given on Days 55 to 60 postpartum, and GnRH was administered 2 days later for synchronization of ovulation. In the FP- groups, endometrial swab and biopsy samples were collected during the second estrus (approximately Day 40) and during the estrus after synchronization. In the FP+ groups, the same samples were collected during the first estrus (approximately Day 49) and during the estrus after synchronization. The prevalence of positive bacteriologic cultures of the endometrium was not affected by FP (P > 0.05). Histologic signs of endometritis were more severe in UD+FP- cows at second sampling than in UD+FP+ cows (P ≤ 0.05). Endometrial expression of IL1α (in UD- after first sampling and in UD+ after second sampling) and IL1ß (in UD- and UD+ after first sampling) was higher (P ≤ 0.05) in FP- cows than in FP+ cows. Regardless of group, cows with histopathologic evidence of endometritis had higher expression (P ≤ 0.05) of IL1α, IL1ß, IL6, and TNFα than cows without endometritis. In conclusion, suppression of early ovulation by transvaginal FP enhances clearance of uterine inflammation in postpartum cows.
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Doenças dos Bovinos/patologia , Endometrite/veterinária , Endométrio/patologia , Inibição da Ovulação , Ovulação/fisiologia , Animais , Bovinos , Citocinas/metabolismo , Endometrite/microbiologia , Endometrite/patologia , Sincronização do Estro , Feminino , Expressão Gênica , Ovulação/efeitos dos fármacos , Período Pós-Parto , Progesterona/sangue , Fatores de TempoRESUMO
The electric-field-induced modification in the Curie temperature of prototypical transition-metal thin films with the perpendicular magnetic easy axis, a freestanding Fe(001) monolayer and a Co monolayer on Pt(111), is investigated by first-principles calculations of spin-spiral structures in an external electric field (E field). An applied E field is found to modify the magnon (spin-spiral formation) energy; the change arises from the E-field-induced screening charge density in the spin-spiral states due to p-d hybridizations. The Heisenberg exchange parameters obtained from the magnon energy suggest an E-field-induced modification of the Curie temperature, which is demonstrated via Monte Carlo simulations that take the magnetocrystalline anisotropy into account.
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Graphene vacancies are engineered for novel functionalities, however, the charge state of these defects, the key parameter that is vital to charge transfer during chemical reactions and carrier scattering, is generally unknown. Here, we carried out atomic resolution imaging of graphene vacancy defects created by Ar plasma using noncontact atomic force microscopy, and made the first determination of their charge state by local contact potential difference measurements. Combined with density functional theory calculations, we show that graphene vacancies are typically positively charged, with size-dependent charge states that are not necessarily integer-valued. These findings provide new insights into carrier scattering by vacancy defects in graphene, as well as its functionalization for chemical sensing and catalysis, and underline the tunability of these functions by controlling the size of vacancy defect.
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Specific communication training is currently not integrated into anesthesiology curricula. At the same time communication is an important key factor when working with colleagues, in the physician-patient relationship, during management of emergencies and in avoiding or reducing the legal consequences of adverse medical events. Therefore, focused attention should be brought to this area. In other high risk industries, specific communication training has been standard for a long time and in medicine there is an approach to teach and train these soft skills by simulation. Systematic communication training, however, is rarely an established component of specialist training. It is impossible not to communicate whereby nonverbal indications, such as gestures, mimic expression, posture and tone play an important part. Miscommunication, however, is common and leads to unproductive behavior. The cause of this is not always obvious. This article provides an overview of the communication models of Shannon, Watzlawick et al. and Schulz von Thun et al. and describes their limitations. The "Process Communication Model®" (PCM) is also introduced. An overview is provided with examples of how this tool can be used to look at the communication process from a systematic point of view. People have different psychological needs. Not taking care of these needs will result in individual stress behavior, which can be graded into first, second and third degrees of severity (driver behavior, mask behavior and desperation). These behavior patterns become exposed in predictable sequences. Furthermore, on the basis of this model, successful communication can be established while unproductive behavior that occurs during stress can be dealt with appropriately. Because of the importance of communication in all areas of medical care, opportunities exist to focus research on the influence of targeted communication on patient outcome, complications and management of emergencies.
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Comunicação , Atenção à Saúde/organização & administração , Anestesia , Competência Clínica , Serviços Médicos de Emergência , Humanos , Erros Médicos/prevenção & controle , Modelos Organizacionais , Relações Médico-PacienteRESUMO
Physicians specializing in dysphagia are needed in modern intensive care medicine. Long-term intubation is associated with aspiration and swallowing disorders. Early and standardised dysphagia management should be initiated during a patient's stay on intensive care unit. A clinically experienced, interdisciplinary team is required to provide optimal care for critically ill patients with dysphagia. Intensive care physicians should therefore know about basics in dysphagiology.
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Cuidados Críticos/métodos , Transtornos de Deglutição/terapia , Medicina Interna , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/mortalidade , Endoscopia , Tecnologia de Fibra Óptica , Humanos , Comunicação Interdisciplinar , Colaboração Intersetorial , Intubação Intratraqueal/efeitos adversos , Equipe de Assistência ao Paciente , Pneumonia Aspirativa/etiologia , Pneumonia Aspirativa/prevenção & controle , Análise de SobrevidaRESUMO
The band structure of the recently synthesized (3 × 3) silicene monolayer on (4 × 4) Ag(111) is investigated using density functional theory. A k-projection technique that includes the kâ¥-dependence of the surface bands is used to separate the contributions arising from the silicene and the substrate, allowing a consistent comparison between the calculations and the angle-resolved photoemission experiments. Our calculations not only reproduce the observed gap and linear dispersion across the K point of (1 × 1) silicene but also demonstrate that these originate from the kâ¥-dependence of Ag(111) substrate states (modified by interactions with the silicene) and not from a Dirac state.
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Nanoribbons are model systems for studying nanoscale effects in graphene. For ribbons with zigzag edges, tunable bandgaps have been predicted due to coupling of spin-polarized edge states, which have yet to be systematically demonstrated experimentally. Here we synthesize zigzag nanoribbons using Fe nanoparticle-assisted hydrogen etching of epitaxial graphene/SiC(0001) in ultrahigh vacuum. We observe two gaps in their local density of states by scanning tunnelling spectroscopy. For ribbons wider than 3 nm, gaps up to 0.39 eV are found independent of width, consistent with standard density functional theory calculations. Ribbons narrower than 3 nm, however, exhibit much larger gaps that scale inversely with width, supporting quasiparticle corrections to the calculated gap. These results provide direct experimental confirmation of electron-electron interactions in gap opening in zigzag nanoribbons, and reveal a critical width of 3 nm for its onset. Our findings demonstrate that practical tunable bandgaps can be realized experimentally in zigzag nanoribbons.
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We report infrared studies of adsorbed atomic oxygen (epoxide functional groups) on graphene. Two different systems are used as a platform to explore these interactions, namely, epitaxial graphene/SiC(0001) functionalized with atomic oxygen (graphene epoxide, GE) and chemically reduced graphene oxide (RGO). In the case of the model GE system, IR reflectivity measurements show that epoxide groups distort the graphene π bands around the K-point, imparting a finite effective mass and contributing to a band gap. In the case of RGO, epoxide groups are found to be present following the reduction treatment by a combination of polarized IR reflectance and transmittance measurements. Similar to the GE system, a band gap in the RGO sample is observed as well.
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When graphene is interfaced with a semiconductor, a Schottky contact forms with rectifying properties. Graphene, however, is also susceptible to the formation of ripples upon making contact with another material. Here we report intrinsic ripple- and electric field-induced effects at the graphene semiconductor Schottky junction, by comparing chemical vapour-deposited graphene transferred on semiconductor surfaces of opposite polarization-the hydrogen-terminated silicon and carbon faces of hexagonal silicon carbide. Using scanning tunnelling microscopy/spectroscopy and first-principles calculations, we show the formation of a narrow Schottky dipole barrier approximately 10 Å wide, which facilitates the observed effective electric field control of the Schottky barrier height. We further find atomic-scale spatial fluctuations in the Schottky barrier that directly follow the undulation of ripples on both graphene-silicon carbide junctions. These findings reveal fundamental properties of the graphene/semiconductor Schottky junction-a key component of vertical graphene devices that offer functionalities unattainable in planar device architecture.
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The objective of this study was to investigate the effects of puerperal uterine disease on uterine blood flow using trans-rectal Doppler sonography. Lactating Holstein Friesian cows (n=44) were divided into two groups based on whether they were healthy (UD-; n=23) or had uterine disease (UD+; n=21) defined as retained fetal membranes and/or metritis. General clinical examination, vaginoscopy, trans-rectal palpation, and trans-rectal B-Mode sonography were conducted on Days 8, 11, 18, 25 and then every 10 days until Day 65 after calving. Doppler sonography of the uterine arteries was conducted on Day 8, during diestrus after the second ovulation (Days 40-60 after calving) and during diestrus before breeding (Days 63-75 after calving). Cows with uterine disease had greater (P<0.05) uterine size as assessed trans-rectally compared with cows of the UD group. Sonographic measurements on Day 11 after parturition revealed a greater (P<0.05) horn diameter in cows of the UD+ than in the UD- group. Both uterine size and uterine horn diameter decreased more earlier following parturition (P<0.05) in cows of the UD- group. Blood flow volume (BFV) was greater and pulsatility index was less on Day 8 after calving in cows of UD+ than UD- group (P<0.05). In cows of the UD-, but not in those of the UD+ group, there was a further reduction in BFV subsequent to Day 45 after calving (P<0.05). The results of this study show that uterine blood flow measures by trans-rectal Doppler sonography are affected by puerperal uterine disease.
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Doenças dos Bovinos/fisiopatologia , Transtornos Puerperais/fisiopatologia , Artéria Uterina/diagnóstico por imagem , Artéria Uterina/fisiopatologia , Doenças Uterinas/fisiopatologia , Útero/irrigação sanguínea , Animais , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/diagnóstico por imagem , Indústria de Laticínios , Dinoprosta/análogos & derivados , Dinoprosta/sangue , Feminino , Transtornos Puerperais/sangue , Transtornos Puerperais/diagnóstico por imagem , Transtornos Puerperais/veterinária , Fluxo Sanguíneo Regional , Ultrassonografia Doppler , Doenças Uterinas/sangue , Doenças Uterinas/diagnóstico por imagem , Doenças Uterinas/veterinária , Útero/diagnóstico por imagem , Útero/fisiopatologiaRESUMO
The objective of this study was to investigate the effect of time of first postpartum ovulation after calving on uterine involution in dairy cows with and without uterine puerperal disease. Transvaginal follicular puncture (FP) of follicles >6 mm suppressed ovulation and development of a CL until Day 42 after calving. Fifty-three lactating Holstein Friesian cows (3.4 ± 1.2 years old, parity 2.5 ± 1.0 [median ± mean absolute deviation]) were divided into groups on the basis of the presence (UD+) or absence (UD-) of uterine disease and whether FP was carried out (FP+) or not (FP-). Uterine disease was defined as the occurrence of retained fetal membranes and/or metritis. This resulted in the following groups: UD-FP- (n = 15), UD-FP+ (n = 13), UD+FP- (n = 13), and UD+FP+ (n = 12). A general examination, vaginoscopy, transrectal palpation, and transrectal B-mode sonography of the reproductive organs were conducted on Days 8, 11, 18, and 25 and then every 10 days until Day 65 after calving. After hormonal synchronization of ovulation (cloprostenol between Days 55 and 60 postpartum and GnRH 2 days later), cows were inseminated in the next spontaneous estrus. On average, the cows ovulated on Day 21.0 ± 6.0 (UD-FP-), 50.0 ± 4.0 (UD-FP+), 16.0 ± 3.0 (UD+FP-), and 48.0 ± 2.0 (UD+FP+) postpartum. Calving-to-conception interval and first-service conception rates were not affected by FP (P > 0.05). Healthy cows with FP had smaller (P < 0.05) uterine horn and cervical diameters assessed sonographically than cows without FP. FP reduced the prevalence of purulent vaginal discharge and uterine size assessed transrectally in UD+ cows (P < 0.05). The results showed that suppression of an early ovulation by transvaginal FP improved uterine involution in cows with and without uterine disease.
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Doenças dos Bovinos/terapia , Inibição da Ovulação , Ovulação/efeitos dos fármacos , Transtornos Puerperais/veterinária , Animais , Bovinos , Doenças dos Bovinos/diagnóstico por imagem , Doenças dos Bovinos/prevenção & controle , Sincronização do Estro , Feminino , Ovulação/fisiologia , Progesterona/sangue , Transtornos Puerperais/prevenção & controle , Transtornos Puerperais/terapia , Fatores de Tempo , UltrassonografiaRESUMO
Using scanning tunneling microscopy and transmission electron microscopy, we demonstrate the existence of antiphase boundaries between neighboring grains shifted by a fraction of a quintuple layer in epitaxial (0001) films of the three-dimensional topological insulator Bi(2)Se(3). Scanning tunneling spectroscopy and first-principles calculations reveal that these antiphase boundaries provide electrostatic fields on the order of 10(8) V/m that locally charge the Dirac states, modulating the carrier density, and shift the Dirac point by up to 120 meV. This intrinsic electric field effect, demonstrated here near interfaces between Bi(2)Se(3) grains, provides direct experimental evidence at the atomic scale that the Dirac states are indeed robust against extended structural defects and tunable by electric field. These results also shed light on the recent observation of coexistence of Dirac states and two-dimensional electron gas on Bi(2)Se(3) (0001) after adsorption of metal atoms and gas molecules.
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The glucocorticoid-induced receptor (GIR) is a stress-responsive gene that is abundantly expressed in forebrain limbic regions. Glucocorticoid-induced receptor has been classified as a Neuropeptide Y-like receptor, however, physiological attributes have not been investigated. In this study, mice lacking GIR (-/-) were screened in various paradigms related to stress, anxiety, activity, memory, fear and reward. GIR -/- mice elicited behavioral insensitivity to the anxiogenic effects of restraint stress. However, hypothalamic pituitary adrenal axis response to stress was not impacted by GIR deficiency. Increased preference for sucrose was observed in GIR -/- mice suggestive of modulation of reward-associated behaviors by the receptor. A delayed acquisition of spatial learning was also observed in GIR -/- mice. There were no effects of genotype on the modulation of anxiety-like behavior, activity, fear-conditioning and extinction. Our data extend previous studies on GIR regulation by glucocorticoids and provide novel evidence for a role of GIR in reward, learning and the behavioral outcomes of stress.
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Ansiedade/genética , Aprendizagem em Labirinto , Receptores Acoplados a Proteínas G/genética , Recompensa , Animais , Ansiedade/etiologia , Medo , Genótipo , Sistema Hipotálamo-Hipofisário/fisiologia , Memória , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sistema Hipófise-Suprarrenal/fisiologia , Restrição Física , Estresse Psicológico/complicações , SacaroseRESUMO
This article describes expert recommendations on the management of patients with acute stroke, who might suffer from dysphagia. The main goal is to reduce the risk of aspiration pneumonia (AP). Nurses or physicians should perform the standardized swallowing assessment (SSA) as soon as possible and speech-language therapists have to perform examinations comprising assessment of predictors for aspiration and for AP as well as the clinical swallowing assessment. Dependent on the results, flexible endoscopic or video fluoroscopic evaluation of swallowing has to be performed so that indications for enteral or oral feeding can be made. Furthermore, the risk of AP can be minimized. This article presents algorithms which enable decision-making with regard to diagnostic and therapeutic measures.