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1.
Opt Express ; 29(5): 6582-6598, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33726176

RESUMO

A combination of advanced light engineering concepts enables a substantial improvement in photon extraction efficiency of micro-cavity-based single-photon sources in the telecom O-band at ∼1.3 µm. We employ a broadband bottom distributed Bragg reflector (DBR) and a top DBR formed in a dielectric micropillar with an additional circular Bragg grating in the lateral plane. This device design includes a doped layer in pin-configuration to allow for electric carrier injection. It provides broadband (∼8-10 nm) emission enhancement with an overall photon-extraction efficiency of ∼83% into the upper hemisphere and photon-extraction efficiency of ∼79% within numerical aperture NA=0.7. The efficiency of photon coupling to a single-mode fiber reaches 11% for SMF28 fiber (with NA=0.12), exceeds 22% for 980HP fiber (with NA=0.2) and reaches ∼40% for HNA fiber (with NA=0.42) as demonstrated by 3D finite-difference time-domain modeling.

2.
Sci Rep ; 8(1): 12465, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-30127469

RESUMO

We developed a linked land-sea modeling framework based on remote sensing and empirical data, which couples sediment export and coral reef models at fine spatial resolution. This spatially-explicit (60 × 60 m) framework simultaneously tracks changes in multiple benthic and fish indicators as a function of land-use and climate change scenarios. We applied this framework in Kubulau District, Fiji, to investigate the effects of logging, agriculture expansion, and restoration on coral reef resilience. Under the deforestation scenario, models projected a 4.5-fold sediment increase (>7,000 t. yr-1) coupled with a significant decrease in benthic habitat quality across 1,940 ha and a reef fish biomass loss of 60.6 t. Under the restoration scenario, models projected a small (<30 t. yr-1) decrease in exported sediments, resulting in a significant increase in benthic habitat quality across 577 ha and a fish biomass gain of 5.7 t. The decrease in benthic habitat quality and loss of fish biomass were greater when combining climate change and deforestation scenarios. We evaluated where land-use change and bleaching scenarios would impact sediment runoff and downstream coral reefs to identify priority areas on land, where conservation or restoration could promote coral reef resilience in the face of climate change.


Assuntos
Antozoários/crescimento & desenvolvimento , Conservação dos Recursos Naturais/métodos , Animais , Biomassa , Mudança Climática , Recifes de Corais , Ecossistema , Fiji , Peixes/crescimento & desenvolvimento , Florestas , Oceanos e Mares
4.
Mucosal Immunol ; 4(5): 564-73, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21412229

RESUMO

Wegener's granulomatosis (WG) is a complex autoimmune disease of unknown etiology, frequently involving localized inflammation of the nasal mucosa as an early manifestation. The current hypothesis suggests that the disease is triggered by a disturbed interaction between genetic and environmental effects, such as an altered microflora at mucosal layers. In this study, a systematic assessment of 49 transcripts with potential pathophysiological relevance was performed using quantitative real-time PCR in nasal mucosa samples of more than 80 individuals, including normal control (NC) individuals and disease controls. In addition, colonization with Staphylococcus aureus was quantified in the same individuals to assess its impact on transcriptomic signatures. Transcription profiles show an increased heterogeneity in diseased individuals. In all, 10 transcripts were identified to be differentially expressed (P≤0.05, false discovery rate ≤0.05) between patients with WG and NC individuals. These transcripts include antimicrobial peptides (human ß-defensin (DEFB)1: fold-change WG vs. controls: +4.45, lysozyme: -3.4, DEFB4 and S100A7 (S100 calcium-binding protein A7): both "switched on" in WG), innate immune receptors (Toll-like receptor 4: -2.1, NOD-like receptor C3: -2.1, scavenger receptor CD36: +2.9), and cytokines (interferon-γ: -14, transforming growth factor-ß 1: -1.4, interleukin-17D: -2.7). These transcriptional profiles are independent of S. aureus colonization. This study for the first time describes that, on the basis of data obtained from the primary nasal tissue, WG exhibits molecular features that allow its differentiation from other inflammatory disorders with involvement of the nasal mucosa. Further studies based on these findings may enable the identification of subphenotypes, which are currently discussed as an important target for a personalized medicine approach, aiming to reduce side effects and the number of therapy non-responders.


Assuntos
Perfilação da Expressão Gênica , Granulomatose com Poliangiite/genética , Granulomatose com Poliangiite/imunologia , Mucosa Nasal/imunologia , Adolescente , Adulto , Idoso , Análise por Conglomerados , Feminino , Regulação da Expressão Gênica/imunologia , Granulomatose com Poliangiite/metabolismo , Granulomatose com Poliangiite/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/metabolismo , Mucosa Nasal/microbiologia , Mucosa Nasal/patologia , Análise de Componente Principal , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/fisiologia , Adulto Jovem
5.
Hamostaseologie ; 31(2): 94-102, 104, 2011 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-21152678

RESUMO

Overwhelming evidence has linked inflammatory disorders to a hypercoagulable state. In fact, thromboembolic complications are among the leading causes of disability and death in many acute and chronic inflammatory diseases. Despite this clinical knowledge, coagulation and immunity were long regarded as separate entities. Recent studies have unveiled molecular underpinnings of the intimate interconnection between both systems. The studies have clearly shown that distinct pro-inflammatory stimuli also activate the clotting cascade and that coagulation in turn modulates inflammatory signaling pathways. In this review, we use evidence from sepsis and inflammatory bowel diseases as a paradigm for acute and chronic inflammatory states in general and rise hypotheses how a systematic molecular understanding of the "inflammation-coagulation" crosstalk may result in novel diagnostic and therapeutic strategies that target the inflammation-induced hypercoagulable state.


Assuntos
Imunidade Inata/fisiologia , Mediadores da Inflamação/fisiologia , Inflamação/fisiopatologia , Transdução de Sinais/fisiologia , Trombofilia/diagnóstico , Trombofilia/fisiopatologia , Animais , Antitrombina III/farmacologia , Colite Ulcerativa/fisiopatologia , Doença de Crohn/fisiopatologia , Citocinas/sangue , Heparina/farmacologia , Humanos , Proteína C/fisiologia , Receptores de Reconhecimento de Padrão/fisiologia , Sepse/fisiopatologia , Trombofilia/genética , Trombofilia/terapia
6.
Langmuir ; 25(4): 2390-401, 2009 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-19143485

RESUMO

The concept of using dispersions of nanoparticles as high refractive index fluids in immersion lithography is examined both from a theoretical and experimental point of view. In the theoretical part we show that gelation and demixing can be controlled in high solid dispersions, needed to achieve a high (refractive) index, by using short stabilizing brushes. We considered both fluid-fluid demixing by using statistical thermodynamics and percolation, computed using liquid-state approaches. Whenever demixing or percolation takes place, the nanoparticle dispersion is unsuited for immersion lithography. The minimum thickness of the stabilizer layer of a stable suspension is estimated assuming particles plus steric stabilizer to act as hard spheres with van der Waals attraction between the cores. Since the van der Waals attraction can be related to the optical properties of the particles and dispersion medium, it is also possible to estimate the refractive index that can be attained with composite immersion fluids. Using materials that are known to be highly transparent in the bulk at a wavelength of 193 nm, indices above 1.8 can be attained. Other materials with higher indices are expected to be transparent at 193 nm due to a blue shift of the UV absorption and enable much higher indices. In the experiment, we show that it is possible to prepare suspensions with particles of about 4 nm diameter that increase the refractive index of the continuous phase with 0.2 at a wavelength of 193 nm. The refractive index and density of such dispersions are proportional to the volume fraction of the disperse phase, and it is shown that the refractive index of the composite fluid can be predicted very well from the optical properties of the components. Furthermore, successful imaging experiments were performed through a dispersion of silica nanoparticles. These findings lead to the conclusion that immersion lithography using nanoparticle dispersions is indeed possible.

7.
Circulation ; 63(2): 442-7, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7449066

RESUMO

Medical control for paramedics by means of radio and ECG telemetry is costly, time consuming, and of unproved value. We assessed the interaction between emergency room physicians and paramedics during ambulance transport of "seriously ill" cardiac patients (cardiac arrest, acute myocardial infarction, or new onset of crescendo angina pectoris) with paramedics in service. Thirty-five percent of all arrhythmias and 35% of potentially life-threatening arrhythmias were misclassified. Correct treatment was rendered in 74% of the cases, although only 65% were correctly diagnosed (p < 0.01). The principal predictive variable for misdiagnosing or incorrectly treating a patient was the presence of a potentially life-threatening arrhythmia, precisely the condition for which medical control and the paramedic system has the most to offer. Only 39% of patients with life-threatening arrhythmias were correctly diagnosed and correctly treated, whereas 64% of patients without life-threatening arrhythmias were correctly diagnosed and correctly treated (p < 0.001). Mortality reflected correct diagnosis and treatment. In-hospital and overall mortalities were 12% and 33%, respectively, for patients who were correctly diagnosed and treated (p < 0.06), compared with 20% and 43%, respectively, for patients who were incorrectly diagnosed or incorrectly treated (p < 0.04). More rigorous medical control is needed to improve the quality of patient care and outcome and to further integrate the advanced life support program into the health care system.


Assuntos
Pessoal Técnico de Saúde , Serviços Médicos de Emergência , Auxiliares de Emergência , Idoso , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/mortalidade , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
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