915 research outputs found
Controlling Nanowire Growth by Light.
Individual Au catalyst nanoparticles are used for selective laser-induced chemical vapor deposition of single germanium nanowires. Dark-field scattering reveals in real time the optical signatures of all key constituent growth processes. Growth is initially triggered by plasmonic absorption in the Au catalyst, while once nucleated the growing Ge nanowire supports magnetic and electric resonances that then dominate the laser interactions. This spectroscopic understanding allows real-time laser feedback that is crucial toward realizing the full potential of controlling nanomaterial growth by light.We acknowledge financial support from EPSRC Grant EP/G060649/1, EP/L027151/1, EP/G037221/1, EPSRC NanoDTC, and ERC Grant LINASS 320503. S.H. acknowledges funding from ERC Grant InsituNANO 279342.This is the author accepted manuscript. The final version is available from ACS via http://dx.doi.org/10.1021/acs.nanolett.5b0295
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Pre-existing invasive fungal infection is not a contraindication for allogeneic HSCT for patients with hematologic malignancies: a CIBMTR study.
Patients with prior invasive fungal infection (IFI) increasingly proceed to allogeneic hematopoietic cell transplantation (HSCT). However, little is known about the impact of prior IFI on survival. Patients with pre-transplant IFI (cases; n=825) were compared with controls (n=10247). A subset analysis assessed outcomes in leukemia patients pre- and post 2001. Cases were older with lower performance status (KPS), more advanced disease, higher likelihood of AML and having received cord blood, reduced intensity conditioning, mold-active fungal prophylaxis and more recently transplanted. Aspergillus spp. and Candida spp. were the most commonly identified pathogens. 68% of patients had primarily pulmonary involvement. Univariate and multivariable analysis demonstrated inferior PFS and overall survival (OS) for cases. At 2 years, cases had higher mortality and shorter PFS with significant increases in non-relapse mortality (NRM) but no difference in relapse. One year probability of post-HSCT IFI was 24% (cases) and 17% (control, P<0.001). The predominant cause of death was underlying malignancy; infectious death was higher in cases (13% vs 9%). In the subset analysis, patients transplanted before 2001 had increased NRM with inferior OS and PFS compared with later cases. Pre-transplant IFI is associated with lower PFS and OS after allogeneic HSCT but significant survivorship was observed. Consequently, pre-transplant IFI should not be a contraindication to allogeneic HSCT in otherwise suitable candidates. Documented pre-transplant IFI is associated with lower PFS and OS after allogeneic HSCT. However, mortality post transplant is more influenced by advanced disease status than previous IFI. Pre-transplant IFI does not appear to be a contraindication to allogeneic HSCT
Electrically Controlled Nano and Micro Actuation in Memristive Switching Devices with On-Chip Gas Encapsulation
Nanoactuators are a key component for developing nanomachinery. Here, an electrically driven device yielding actuation stresses exceeding 1 MPa withintegrated optical readout is demonstrated. 10 nm thick Al2O3 electrolyte films are sandwiched between graphene and Au electrodes. These allow reversible room-temperature solid-state redox reactions, producing Al metal and O2 gas in a memristive-type switching device. The resulting high-pressure oxygen micro-fuel reservoirs are encapsulated under the graphene, swelling to heights of up to 1 µm, which can be dynamically tracked by plasmonic rulers. Unlike standard memristors where the memristive redox reaction occurs in single or few conductive filaments, the mechanical deformation forces the creation of new filaments over the whole area of the inflated film. The resulting on–off resistance ratios reach 10^8 in some cycles. The synchronization of nanoactuation and memristive switching in these devices is compatible with large-scale fabrication and has potential for precise and electrically monitored actuation technology
Plasmonic response and SERS modulation in electrochemical applied potentials
We study the optical response of individual nm-wide plasmonic nanocavities using a nanoparticle-on-mirror design utilised as an electrode in an electrochemical cell. In this geometry Au nanoparticles are separated from a bulk Au film by an ultrathin molecular spacer, giving intense and stable Raman amplification of 100 molecules. Modulation of the plasmonic spectra and the SERS response is observed with an applied voltage under a variety of electrolytes. Different scenarios are discussed to untangle the various mechanisms that can be involved in the electronic interaction between NPs and electrode surfaces.We acknowledge financial support from EPSRC grant EP/G060649/1, EP/L027151/1, EP/G037221/1, EPSRC NanoDTC, and ERC grant LINASS 320503. C. T. was supported by funding from the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework Programme (FP7/2007–2013) under REA grant agreement number 609405 (COFUNDPostdocDTU)
Structured Multi-Level Feature Interaction Identification
This is a conference paper.Features are an established means of adding non-geometric information and extra geometric semantics to conventional
CAD systems. It has been already realised that although feature-based modelling is necessary for the next generation of
integrated design and manufacturing systems, inherent feature interactions pose a difficulty in representing and
manipulating geometric design. This paper presents a structured multi-level geometric feature interaction classification
scheme implemented within a Design-by Feature (DbF) system for representation validation analysis. Various feature
interaction definitions and classification methods are first surveyed. The elements and the tests used for the
identification process are presented. The classification encompasses existing feature interference cases found in the
literature, uses a clear structure for the classification and, is applied at three different levels
Red blood cell glutathione peroxidase activity in female nulligravid and pregnant rats
<p>Abstract</p> <p>Background</p> <p>The alterations of the glutathione peroxidase enzyme complex system occur in physiological conditions such as aging and oxidative stress consequent to strenuous exercise.</p> <p>Methods</p> <p>Authors optimize the spectrophotometric method to measure glutathione peroxidase activity in rat red blood cell membranes.</p> <p>Results</p> <p>The optimization, when applied to age paired rats, both nulligravid and pregnant, shows that pregnancy induces, at seventeen d of pregnancy, an increase of both reactive oxygen substance concentration in red blood cells and membrane glutathione peroxidase activity.</p> <p>Conclusion</p> <p>The glutathione peroxidase increase in erythrocyte membranes is induced by systemic oxidative stress long lasting rat pregnancy.</p
A case of native valve endocarditis caused by Burkholderia cepacia without predisposing factors
Time constraints on the tectonic evolution of the Eastern Sierras Pampeanas (Central Argentina)
Complete abdominal aortic aneurysm thrombosis and obstruction of both common iliac arteries with intrathrombotic pressures demonstrating a continuing risk of rupture: a case report and review of the literature
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