289 research outputs found
Embedded micro-mirrors for compact routing of multimode polymer waveguides
The limited scalability of high-speed electrical interconnects drives research on optical interconnect technologies. This work is concerned with compact polymer waveguide routing schemes for optical printed circuit boards (PCB). The developed embedded micro-mirrors are an integral part of the waveguide layer. The micro-structures that make up their bodies are fabricated directly onto the lower cladding of the waveguide by means of UV-laser patterning of a photosensitive resin. Vertical and 45°-tilted micro-structures are eventually used as in-plane and out-of-plane micro-mirrors, respectively. A wet-chemical deposition process is developed to apply the reflective metal layer selectively on the micro-structures. The fabrication processes are compatible to polymer waveguide and PCB manufacturing equipment. An electro-optical flex board is designed as basis for an optical transceiver module. Therein implemented are mechanical fiducial markers for adjustment-free alignment of the optical connector and the embedded out-of-plane micro-mirrors. The latter will vertically couple the light path from the laser- or detector-array to the polymer waveguide array. In a second part, an experimental approach to characterize the modal power coupling of light propagating in polymer waveguides is investigated. A modal power coupling matrix is thereby used to describe the relation between the input and output modal power distribution of a waveguide. The specific mode launch, required to control the input modal power distribution, is realized by an intensity- and a phase-controlling spatial light modulator (SLM). The modal power distribution at the end facet of the waveguide is analyzed by an approach based on optical Fourier transformation
T-helper cells as new players in ANCA-associated vasculitides
In anti-neutrophil cytoplasmic autoantibody-associated vasculitides (AAV), several observations support a key role of T-helper cells (CD4+ T cells) in disease pathophysiology. An expanded population of effector memory CD4+ T cells in AAV patients may contribute to tissue injury and disease progression. In addition, functional impairment of regulatory T cells (TRegs) is reported in AAV patients. A fraction of TRegs have the capacity to differentiate into Th17 cells in the context of a proinflammatory environment. Therefore, nonfunctionality of TRegs described in AAV patients may be caused by their conversion into IL-17-producing cells that may contribute to granulomatous vasculitis. Further investigations directed at the plasticity of TRegs in AAV patients are warranted
AFM imaging of functionalized double-walled carbon nanotubes
We present a comparative study of several non-covalent approaches to disperse, debundle and noncovalently functionalize double-walled carbon nanotubes (DWNTs). We investigated the ability of bovine serum albumin (BSA), phospholipids grafted onto amine-terminated polyethylene glycol (PLPEG2000-NH2), as well as a combination thereof, to coat purified DWNTs. Topographical imaging with the atomic force microscope (AFM) was used to assess the coating of individual DWNTs and the degree of debundling and dispersion. Topographical images showed that functionalized DWNTs are better separated and less aggregated than pristine DWNTs and that the different coating methods differ in their abilities to successfully debundle and disperse DWNTs. Height profiles indicated an increase in the diameter of DWNTs depending on the functionalization method and revealed adsorption of single molecules onto the nanotubes. Biofunctionalization of the DWNT surface was achieved by coating DWNTs with biotinylated BSA, providing for biospecific binding of streptavidin in a simple incubation step. Finally, biotin-BSA-functionalized DWNTs were immobilized on an avidin layer via the specific avidin–biotin interaction
AFM imaging of functionalized carbon nanotubes on biological membranes
Multifunctional carbon nanotubes are promising for biomedical applications as their nano-size, together with their physical stability, gives access into the cell and various cellular compartments including the nucleus. However, the direct and label-free detection of carbon nanotube uptake into cells is a challenging task. The atomic force microscope (AFM) is capable of resolving details of cellular surfaces at the nanometer scale and thus allows following of the docking of carbon nanotubes to biological membranes. Here we present topographical AFM images of non-covalently functionalized single walled (SWNT) and double walled carbon nanotubes (DWNT) immobilized on different biological membranes, such as plasma membranes and nuclear envelopes, as well as on a monolayer of avidin molecules. We were able to visualize DWNT on the nuclear membrane while at the same time resolving individual nuclear pore complexes. Furthermore, we succeeded in localizing individual SWNT at the border of incubated cells and in identifying bundles of DWNT on cell surfaces by AFM imaging
A 160Gb/s (4x40) WDM O-band Tx subassembly using a 4-ch array of silicon rings co-packaged with a SiGe BiCMOS IC driver
We present a 400 (8×50) Gb/s-capable RM-based Si-photonic WDM O-band TxRx with 1.17nm channel spacing for high-speed optical interconnects and demonstrate successful 50Gb/s-NRZ TxRx operation achieving a ~4.5dB Tx extinction ratio under 2.15Vpp drive
4-channel 200 Gb/s WDM O-band silicon photonic transceiver sub-assembly
We demonstrate a 200G capable WDM O-band optical transceiver comprising a 4-element array of Silicon Photonics ring modulators (RM) and Ge photodiodes (PD) co-packaged with a SiGe BiCMOS integrated driver and a SiGe transimpedance amplifier (TIA) chip. A 4 x 50 Gb/s data modulation experiment revealed an average extinction ratio (ER) of 3.17 dB, with the transmitter exhibiting a total energy efficiency of 2 pJ/bit. Data reception has been experimentally validated at 50 Gb/s per lane, achieving an interpolated 10E-12 bit error rate (BER) for an input optical modulation amplitude (OMA) of -9.5 dBm and a power efficiency of 2.2 pJ/bit, yielding a total power efficiency of 4.2 pJ/bit for the transceiver, including heater tuning requirements. This electro-optic subassembly provides the highest aggregate data-rate among O-band RM-based silicon photonic transceiver implementations, highlighting its potential for next generation WDM Ethernet transceivers. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
Protocol of a phase II trial
Background Current studies on salvage radiotherapy (sRT) investigate timing,
dose-escalation and anti-hormonal treatment (ADT) for recurrent prostate
cancer. These approaches could either be limited by radiation-related
susceptibility of the anastomosis or by suspected side-effects of long-term
ADT. A phase II protocol was developed to investigate the benefit and
tolerability of regional hyperthermia with moderately dose-escalated
radiotherapy. Methods The study hypothesis is that radio-thermotherapy is a
safe and feasible salvage treatment modality. The primary endpoint is safety
measured by frequency of grade 3+ genitourinary (GU) and gastrointestinal (GI)
adverse events (AE) according to Common Toxicity Criteria (CTC) version 4.
Feasibility is defined by number of hyperthermia treatments (n ≥ 7) and
feasibility of radiotherapy according to protocol. Target volume delineation
is performed according to the EORTC guidelines. Radiation treatment is
administered with single doses of 2 Gy 5×/week to a total dose of 70 Gy.
Regional hyperthermia is given 2×/week to a total of 10 treatments. Results
European centres participate in the phase II trial using intensity modulated
RT (IMRT) or volumetric modulated arc technique (VMAT). The initiating centres
were participants of the SAKK 09/10 study, where the same patient criteria and
target volume definition (mandatory successful performed dummy run) were
applied insuring a high standardisation of the study procedures. Conclusions
The introduced phase II study implements highly precise image-guided
radiotherapy and regional hyperthermia. If the phase II study is found to be
safe and feasible, a multicenter phase III study is planned to test whether
the addition of regional hyperthermia to dose-intensified sRT improves
biochemical control
Granulomatous Inflammation in ANCA-Associated Vasculitis
ANCA-associated vasculitis (AAV) comprises granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). While systemic vasculitis is a hallmark of all AAV, GPA is characterized by extravascular granulomatous inflammation, preferentially affecting the respiratory tract. The mechanisms underlying the emergence of neutrophilic microabscesses; the appearance of multinucleated giant cells; and subsequent granuloma formation, finally leading to scarred or destroyed tissue in GPA, are still incompletely understood. This review summarizes findings describing the presence and function of molecules and cells contributing to granulomatous inflammation in the respiratory tract and to renal inflammation observed in GPA. In addition, factors affecting or promoting the development of granulomatous inflammation such as microbial infections, the nasal microbiome, and the release of damage-associated molecular patterns (DAMP) are discussed. Further, on the basis of numerous results, we argue that, in situ, various ways of exposure linked with a high number of infiltrating proteinase 3 (PR3)- and myeloperoxidase (MPO)-expressing leukocytes lower the threshold for the presentation of an altered PR3 and possibly also of MPO, provoking the local development of ANCA autoimmune responses, aided by the formation of ectopic lymphoid structures. Although extravascular granulomatous inflammation is unique to GPA, similar molecular and cellular patterns can be found in both the respiratory tract and kidney tissue of GPA and MPA patients; for example, the antimicrobial peptide LL37, CD163+ macrophages, or regulatory T cells. Therefore, we postulate that granulomatous inflammation in GPA or PR3-AAV is intertwined with autoimmune and destructive mechanisms also seen at other sites
SemOpenAlex
Ce document présente le projet SemOpenAlex, qui contient plus de 26 milliards de triplets RDF concernant des publications scientifiques et leurs entités (entités-relations) associées, comme les auteurs, les institutions, les revues.
SemOpenAlex est sous licence CC0. Ce projet fournit gratuitement et librement un accès aux données. Les données sont proposées par plusieurs canaux
- …