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BACKGROUND: Health care for the increasing number of patients with chronic illnesses has become a major challenge to the politics of public health, especially in rural areas. Follow-up care for those patients requires a great amount of resources. Apart from managing appointments, patients often have to accept long journeys and waiting times. OBJECTIVE: Implementation of teledermatology solutions, providing telemedicine care for patients with skin diseases in structurally weak regions. Using the example of the region Mecklenburg-Vorpommern (MV), the main focus was to build and expand a telemedicine structure in an area where the number of registered specialist physicians is expected to continually decline. A further objective was to intensify the cross-sectoral and interdisciplinary cooperation between physicians and dermatologists, as well as hospitals (teleconsultation module). METHODS: To ensure the highest level of comprehensive care, the project partners currently involved are: 10 dermatologists, 95 physicians, 10 emergency departments of hospitals and one rehabilitation clinic in MV. The challenge of designing a solution that incorporates complex medical data, as well as adhering to the legal requirements of data protection and data security (GDPR, eHealth law, eHealth initiative), has been met. RESULTS AND DISCUSSION: An innovative solution to support the care of patients with chronic skin diseases or wounds has been developed and implemented. Mobile applications and web applications have been designed and are running on the secure telematics platform. The teleconsultation module is being used. CONCLUSION: Teledermatolocial solutions offer measurable benefits to patients and health care providers and can be seamlessly incorporated into existing settings.
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Dermatopatias , Telemedicina , Atenção à Saúde , Dermatologistas , Humanos , Saúde Pública , Dermatopatias/diagnóstico , Dermatopatias/terapiaRESUMO
Anisotropic magnetoresistance, that is, the sensitivity of the electrical resistance of magnetic materials on the magnetization direction, is expected to be strongly enhanced in ballistic transport through nanoscale junctions. However, unambiguous experimental evidence of this effect is difficult to achieve. We utilize single-atom junctions to measure this ballistic anisotropic magnetoresistance (AMR). Single Co and Ir atoms are deposited on domains and domain walls of ferromagnetic Fe layers on W(110) to control their magnetization directions. They are contacted with nonmagnetic tips in a low-temperature scanning tunneling microscope to measure the junction conductances. Large changes of the magnetoresistance occur from the tunneling to the ballistic regime due to the competition of localized and delocalized d-orbitals, which are differently affected by spin-orbit coupling. This work shows that engineering the AMR at the single atom level is feasible.
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Foveolar gastric metaplasia of the duodenum (FGM) is considered as imperfect mucosal healing in the context of H. pylori gastritis and intake of NSAIDs or ASS.â Typical endoscopic findings are redness of the mucosa, erosion/ulcer and loss of mucosal folds. During diagnostic histological examinations we observed a frequent so far not described association of FGM with endoscopically observed duodenal polyps. The archives of two institutes of pathology with high gastroenterological workload (approximately 100â000 patients per year) were investigated for an association between "duodenal polyp" and "foveolar gastric metaplasia". In Institute 1, of 481 duodenal polyps 41â% were classified as FGM, 9â% as adenoma and 2â% as heterotopic gastric mucosa. In 48â% no histological correlate was present. In Institute 2, 217 cases of FGM were diagnosed. Of these, in 69 cases the endoscopic finding was "polyp" (32â%). In the other cases, the endoscopic findings were mucosal defect (18â%), redness/inflammation (16â%), suspicion for gastric heterotopia (5â%) and scar (3â%). In 26â% of cases no pathologic endoscopic finding was reported. Both groups of patients with FGM showed a similar distribution of age ranges (24â-â83 years and 16â-â88 years), median age (62 years and 61 years, respectively) and a dominance of male sex (both 1.5:1). In conclusion, foveolar gastric metaplasia is a frequent, so far neglected correlate of endoscopically detected duodenal polyps.
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Duodenopatias/epidemiologia , Duodenopatias/patologia , Mucosa Gástrica/patologia , Pólipos Intestinais/epidemiologia , Pólipos Intestinais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Metaplasia/epidemiologia , Metaplasia/patologia , Pessoa de Meia-Idade , Fatores de Risco , Adulto JovemRESUMO
The tunneling anisotropic magnetoresistance (TAMR) of single Co atoms adsorbed on a double-layer Fe film on W(110) is observed by scanning tunneling spectroscopy. Without applying an external magnetic field the TAMR is found by comparing spectra of atoms that are adsorbed on the domains and domain walls of the Fe film. The TAMR can be as large as 12% and repeatedly changes sign as a function of bias voltage. First-principles calculations show that the hybridization between Co d states of different orbital symmetries depends on the magnetization direction via spin-orbit coupling. This leads to an anisotropy of the density of states and thus induces a TAMR.
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We report on three cases of serrated polyps of the duodenum which were incidental endoscopic findings in three male patients with a median age of 70 years (range 63-84 years). Architecturally the histological findings in cases 1 and 2 were similar to hyperplastic polyps of the colon. In case 3 there was a low grade intraepithelial neoplasia which covered the whole polyp. This polyp relapsed after 2 years with similar histological findings. Immunohistochemically an increased proliferative activity was found in case 3 as well as associated overexpression of p16 (INK4a) and p53. No abnormal expression of MLH1 and ß-catenin was found in any of the polyps. Molecular pathological analysis showed a BRAF mutation (V600E) in case 3. A wild type sequence in the KRAS gene was found in all polyps. In conclusion, serrated polyps should be included in the diagnostic spectrum of benign duodenal polyps.
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Neoplasias Duodenais/genética , Neoplasias Duodenais/patologia , Pólipos Intestinais/genética , Pólipos Intestinais/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Análise Mutacional de DNA , Duodenoscopia , Duodeno/patologia , Expressão Gênica/genética , Humanos , Achados Incidentais , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Proteína Supressora de Tumor p53/genéticaRESUMO
The emission of plasmonic light from a single C(60) molecule on Cu(111) is probed in a scanning tunneling microscope from the weak-coupling, tunneling range to strong coupling of the molecule to the electrodes at contact. At positive sample voltage the photon yield decreases owing to shot-noise suppression in an increasingly transparent quantum contact. At reversed bias an unexpected nonlinear increase occurs. First-principles transport calculations reveal that ultrafast charge fluctuations on the molecule give rise to additional noise at optical frequencies beyond the shot noise of the current that is injected to the tip.
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The influence of graphene islands on the electronic structure of the Ir(111) surface is investigated. Scanning tunneling spectroscopy (STS) indicates the presence of a two-dimensional electron gas with a binding energy of -160 meV and an effective mass of -0.18me underneath single-layer graphene on the Ir(111) surface. Density functional calculations reveal that the STS features are predominantly due to a holelike surface resonance of the Ir(111) substrate. Nanometer-sized graphene islands act as local gates, which shift and confine the surface resonance.
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The conductance of a single-molecule junction in a low-temperature scanning tunneling microscope has been measured at nanosecond time resolution. In a transition region between tunneling and contact the conductance exhibits rapid two-level fluctuations which are attributed to different geometries of the junction. The voltage dependence of the fluctuations indicates that electrons injected into the lowest unoccupied molecular orbital may efficiently couple to molecular vibrations.
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Linear CoCu(n)Co clusters on Cu(111) fabricated by atomic manipulation represent a two-site Kondo system with tunable interaction. Scanning tunneling spectroscopy reveals oscillations of the Kondo temperature T(K) with the number n of Cu atoms for n≥3. Density functional calculations show that the Ruderman-Kittel-Kasuya-Yosida interaction mediated by the Cu chains causes the oscillations. Calculations find ferromagnetic and antiferromagnetic interaction for n=1 and 2, respectively. Both interactions lead to a decrease of T(K) as experimentally observed.
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Lead phthalocyanine (PbPc) deposited on lead islands on Ag(111) forms two-dimensional crystals of densely packed molecules. For particular orientations, the molecular arrays exhibit an electronic superstructure with an extraordinarily large unit cell. The molecules induce a shift of quantum well states, which are confined to the Pb islands. Patterns formed by PbPc on Ag(111) are drastically different.
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Graphene on Ru(0001) is contacted with Au tips of a cryogenic scanning tunneling microscope. The formation and conductance of single-atom contacts vary within the moiré unit cell. Density functional calculations reveal that elastic distortions of the graphene lattice occur at contact due to a selectively enhanced chemical reactivity of C atoms at hollow sites of Ru(0001). Concomitant quantum transport calculations indicate that the graphene-Ru distance determines the conductance variations.
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Tin-phthalocyanine molecules adsorbed on Ag(111) were contacted with the tip of a cryogenic scanning tunneling microscope. Orders-of-magnitude variations of the single-molecule junction conductance were achieved by controllably dehydrogenating the molecule and by modifying the atomic structure of the surface electrode. Nonequilibrium Green's function calculations reproduce the trend of the conductance and visualize the current flow through the junction, which is guided through molecule-electrode chemical bonds.
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The scanning tunnelling microscope (STM) may be used to prepare contacts to single atoms or molecules on surfaces and to investigate the transport of electrons through these junctions. The imaging capabilities of STM along with spectroscopic modes of measurement enable a rather detailed characterisation of the geometric and electronic properties of the contacts. This perspective presents recent investigations into the quantum transport through magnetic atoms and C(60) molecules.
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Direct evidence of successful or failed predation is rare in the fossil record but essential for reconstructing extinct food webs. Here, we report the first evidence of a failed predation attempt by a pterosaur on a soft-bodied coleoid cephalopod. A perfectly preserved, fully grown soft-tissue specimen of the octobrachian coleoid Plesioteuthis subovata is associated with a tooth of the pterosaur Rhamphorhynchus muensteri from the Late Jurassic Solnhofen Archipelago. Examination under ultraviolet light reveals the pterosaur tooth is embedded in the now phosphatised cephalopod soft tissue, which makes a chance association highly improbable. According to its morphology, the tooth likely originates from the anterior to middle region of the upper or lower jaw of a large, osteologically mature individual. We propose the tooth became associated with the coleoid when the pterosaur attacked Plesioteuthis at or near the water surface. Thus, Rhamphorhynchus apparently fed on aquatic animals by grabbing prey whilst flying directly above, or floating upon (less likely), the water surface. It remains unclear whether the Plesioteuthis died from the pterosaur attack or survived for some time with the broken tooth lodged in its mantle. Sinking into oxygen depleted waters explains the exceptional soft tissue preservation.
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Dinossauros/fisiologia , Comportamento Alimentar/fisiologia , Animais , Evolução Biológica , Cefalópodes , Dieta/veterinária , Fósseis , Comportamento Predatório , Répteis/fisiologiaRESUMO
The tip-surface region of a scanning tunneling microscope (STM) emits light when the energy of the tunneling electrons is sufficient to excite luminescent processes. These processes provide access to dynamic aspects of the local electronic structure that are not directly amenable to conventional STM experiments. From monolayer films of carbon-60 fullerenes on gold(110) surfaces, intense emission is observed when the STM tip is placed above an individual molecule. The diameter of this emission spot associated with carbon-60 is approximately 4 angstroms. These results demonstrate the highest spatial resolution of light emission to date with a scanning probe technique.
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Electron transport through a single C60 molecule on Cu(1 1 1) has been investigated with a scanning tunnelling microscope in tunnelling and contact ranges. Single-C60 junctions have been fabricated by establishing a contact between the molecule and the tip, which is reflected by a down-shift in the lowest unoccupied molecular orbital resonance. These junctions are stable even at elevated bias voltages enabling conductance measurements at high voltages and nonlinear conductance spectroscopy in tunnelling and contact ranges. Spectroscopy and first principles transport calculations clarify the relation between molecular orbital resonances and the junction conductance. Due to the strong molecule-electrode coupling the simple picture of electron transport through individual orbitals does not hold.
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Four types of ascomycete mycorrhizas were found on seedlings of Abies alba grown in pot cultures on mineral soil. One type was formed by Cenococcum graniforme Ferd. & Winge; the fungal partners of the other three types could not be identified. The macroscopic and microscopic characteristics are described. One mycorrhiza appeared to be identical with Type 15 of Haug & Oberwinkler, found in natural spruce stands. Senescent stages of this type are also described. Ultrastructural investigations showed that the dolipore seemed to be the main distinguishing feature between ascomycete and basidiomycete mycorrhizas. Differences in the matrix of the interface and the fungal wall were not stable enough to be used as a distinguishing feature between asco- and basidiomycetes. Dead fungal cells were isolated from the living tissue by plugging of septa with Woronin bodies and walling-over of the plugged septa. Subsequently these isolated dead cells could be colonized by the fungus. The predominant mycorrhization of the fir seedlings by ascomycetes in pot culture with mineral soil is discussed.
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The functional source(s) of agrammatic aphasic patients' difficulty comprehending semantically reversible active and passive sentences was investigated in a meta-analysis of published sentence/picture matching data from patients with agrammatic production. The analysis revealed approximately equal distributions of three distinct patterns of performance on active and passive voice sentences relative to what would be expected by chance: both structures comprehended better than chance; both structures comprehended no better than chance; active voice sentences comprehended better than chance, while passive voice sentences were comprehended at levels no better than (or worse than) chance. These results are in conflict with explanations of aphasic sentence comprehension failure in which a single pattern of relative performance on active and passive voice structures is asserted to be characteristic of the comprehension of all agrammatic speakers. They also highlight the difficulty of identifying any single causal factor to account for sentence comprehension failure in patients with "agrammatic" sentence production. Results are interpreted with regard to the role of data from aphasic patients in the testing of hypotheses about the organization of normal language processes.
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Afasia de Broca , Idioma , HumanosRESUMO
Modification of the electronic structure of a single Mn adsorbate placed within a geometrical array of adatoms on Ag(111) is observed using local spectroscopy with the scanning tunneling microscope. The changes result from coupling between the adsorbate level and surface electronic states of the substrate. These surface states are scattered coherently within the adatom array, mediating the presence and shape of the array to the adsorbate within. The dimension and geometry of the adatom array thus provide a degree of control over the induced changes.
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The present study was concerned with whether there are separate, modality-specific processing "streams" in verbal working memory for information that is heard or read. We used event-related brain potentials (ERPs) recorded from scalp of normal humans to show between-modality differences in spatio-temporal patterns of brain activity during retention in working memory of aurally or visually presented verbal information. The ERP patterns suggested that a sustained, automatically maintained auditory store was activated by auditory presentation and a transient, visual-verbal store was activated by visual presentation. In addition to these modality-specific differences, the ERPs indicated that the phonological loop was activated in both modalities and further suggested that the onset of phonological loop activation was earlier for auditory presentation.