1,622 research outputs found
Characterization of the Soluble Nanoparticles Formed through Coulombic Interaction of Bovine Serum Albumin with Anionic Graft Copolymers at Low pH
A static light scattering (SLS) study of bovine serum albumin (BSA) mixtures
with two anionic graft copolymers of poly (sodium acrylate-co-sodium
2-acrylamido-2-methyl-1-propanesulphonate)-graft-poly (N,
N-dimethylacrylamide), with a high composition in poly (N,
N-dimethylacrylamide) (PDMAM) side chains, revealed the formation of oppositely
charged complexes, at pH lower than 4.9, the isoelectric point of BSA. The
core-corona nanoparticles formed at pH = 3.00, were characterized. Their
molecular weight and radius of gyration were determined by SLS, while their
hydrodynamic radius was determined by dynamic light scattering. Small angle
neutron scattering measurements were used to determine the radius of the
insoluble complexes, comprising the core of the particles. The values obtained
indicated that their size and aggregation number of the nanoparticles, were
smaller when the content of the graft copolymers in neutral PDMAM side chains
was higher. Such particles should be interesting drug delivery candidates, if
the gastrointestinal tract was to be used
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Structure in mind, structure in vocal tract
We update our understanding of the view that grammar regulates intersegmental temporal coordination and present an extension of that view to a new domain: we argue that inter-segmental coordination is basic to prosody. It is the glue joining segments together differently in different languages (here, illustrated with examples from Arabic and Spanish) and orchestrates their unfolding in ways corresponding to constructs posited in theoretical analysis. The correspondence is one between organization in mind-brain and organization in vocal tract. Moreover, for both mind-brain and vocal tract, the organization is phonological and abstract. It is so because it holds over segments of various identities: in Arabic, the first segment in /bka/ is not prosodified as part of the same unit as /ka/ and this holds true also for /blat/, /klat/ and so on, regardless of sonority. In contrast, in English or Spanish, a different organization holds. Crucially, uniformity in organization (same organization presiding over sequences with varying segmental makeup) does not imply uniqueness of phonetic exponents: prosodic organization is pleiotropic, simultaneously expressed by more than one phonetic exponent. Finally, two properties of coordination relations are underscored: lawful flexibility and abstractness. The first is revealed in the degrees of freedom with which movements corresponding to any given effector begin; the second in invariances of task-relevant kinematic signatures regardless of the effectors implicated in any given segmental sequence. Once again, abstract phonological structure is mirrored in vocal tracts via coordination relations holding across physiology and the particular modes of its operation
A Guidebook: navigating custody and access negotiation
guidelines for family negotiation: what to do in the interest of minors after a family breakup
Image processing applications: From particle physics to society
We present an embedded system for extremely efficient real-time pattern recognition execution, enabling technological advancements with both scientific and social impact. It is a compact, fast, low consumption processing unit (PU) based on a combination of Field Programmable Gate Arrays (FPGAs) and the full custom associative memory chip. The PU has been developed for real time tracking in particle physics experiments, but delivers flexible features for potential application in a wide range of fields. It has been proposed to be used in accelerated pattern matching execution for Magnetic Resonance Fingerprinting (biomedical applications), in real time detection of space debris trails in astronomical images (space applications) and in brain emulation for image processing (cognitive image processing). We illustrate the potentiality of the PU for the new applications
Reduced uptake of the proliferation-seeking radiotracer technetium-99m-labelled pentavalent dimercaptosuccinic acid in a 47-year-old woman with severe breast epithelial hyperplasia taking ibuprofen: a case report
<p>Abstract</p> <p>Introduction</p> <p>Recent studies have reported a risk reduction in the progression of benign breast disease to breast carcinoma through COX-2 pathways.</p> <p>Case presentation</p> <p>We present a case of severe epithelial hyperplasia in a 47-year-old woman with increased breast density submitted to scintimammography by the proliferation-imaging tracer Technetium-99m-labelled pentavalent dimercaptosuccinic acid, before and after an oral ibuprofen treatment for 4 weeks. The radiotracer uptake after ibuprofen intake was significantly reduced, both visually and by semi-quantitative analysis, based on a calculation of lesion-to-background ratios.</p> <p>Conclusion</p> <p>In proliferating breast lesions, scintigraphically displayed reduction in Technetium-99m-labelled pentavalent dimercaptosuccinic acid uptake may indicate inhibition by ibuprofen in the pathway of malignant epithelial cell transformation.</p
Performing Values Practices and Grassroots Organizing: The Case of Solidarity Economy Initiatives in Greece
This article discusses solidarity economy initiatives as instances of grassroots organizing, and explores how ‘values practices’ are performed collectively during times of crisis. In focusing on how power, discourse and subjectivities are negotiated in the everyday practices of grassroots exchange networks (GENs) in crisis-stricken Greece, the study unveils and discusses three performances of values practices, namely mobilization of values, re-articulation of social relations, and sustainable living. Based on these findings, and informed by theoretical analyses of performativity, we propose a framework for studying the production and reproduction of values in the context of GENs, and the role of values in organizing alternatives
Ancient encaustic: An experimental exploration of technology, ageing behaviour and approaches to analytical investigation
The composition of the ancient wax-based painting technique known as encaustic has long been the subject of debate. Ancient sources provide few details of the technology, and modern understanding of the medium is restricted to theoretical interpretation and experimental observation. In this multi-analytical collaborative study, a number of analytical approaches were used to investigate the physical and molecular properties of a range of experimentally prepared encaustic paints before and after ageing. Analysis using gas chromatography mass spectrometry, Fourier transform infrared spectroscopy (invasive and non-invasive), X-ray diffraction and thermogravimetric analysis demonstrated how differences in the technology of production alter the properties and composition of the medium and showed how these are modified by the addition of pigment and the effects of ageing. Comparison of results from the different analytical techniques highlights the benefit of an integrated analytical approach to the analysis of ancient encaustic paints and the fundamental importance of insights from invasive study to evaluating the results of non-invasive analysis
Dual Energy Method for Breast Imaging: A Simulation Study
Dual energy methods can suppress the contrast between adipose and glandular tissues in the breast and therefore enhance the visibility of calcifications. In this study, a dual energy method based on analytical modeling was developed for the detection of minimum microcalcification thickness. To this aim, a modified radiographic X-ray unit was considered, in order to overcome the limited kVp range of mammographic units used in previous DE studies, combined with a high resolution CMOS sensor (pixel size of 22.5 m) for improved resolution. Various filter materials were examined based on their K-absorption edge. Hydroxyapatite (HAp) was used to simulate microcalcifications. The contrast to noise ratio (CNR ) of the subtracted images was calculated for both monoenergetic and polyenergetic X-ray beams. The optimum monoenergetic pair was 23/58 keV for the low and high energy, respectively, resulting in a minimum detectable microcalcification thickness of 100 m. In the polyenergetic X-ray study, the optimal spectral combination was 40/70 kVp filtered with 100 m cadmium and 1000 m copper, respectively. In this case, the minimum detectable microcalcification thickness was 150 m. The proposed dual energy method provides improved microcalcification detectability in breast imaging with mean glandular dose values within acceptable levels
Pooled peptides from HER-2/neu-overexpressing primary ovarian tumours induce CTL with potent antitumour responses in vitro and in vivo
Unfractionated peptides (MW: up to 10 kDa), derived from HLA-A2.1 positive (+) HER-2/neu-overexpressing primary tumour cell acid cell extracts (ACE), were successfully used to generate in vitro cytotoxic T lymphocytes (CTL). Primary tumour cells were collected from peritoneal malignant effusions of patients with ovarian cancer. Acid cell extracts-induced CTL specifically lysed in an HLA-A2-restricted manner HER-2/neu+ autologous primary tumour cells as well as HER-2/neu+ tumour cell lines. In addition, adoptive transfer of such CTL significantly prolonged the survival of SCID mice xenografted with HLA-A2.1+, HER-2/neu+ human breast and ovarian tumour cell lines. Acid cell extracts collected from HLA-A2.1+ HER-2/neu negative (−) primary ovarian tumours induced HLA-A2.1-restricted CTL with weak in vitro and in vivo antitumour capacity, suggesting that HER-2/neu peptides within ACE from HER-2/neu-overexpressing primary ovarian tumour cells are immunodominant. The results presented herein serve as a rationale for the initiation of vaccination studies in patients with HER-2/neu-overexpressing ovarian tumours utilising autologous tumour-derived ACE
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