1,145 research outputs found
Identifying Clinical applications of Spectroscopic x-ray imaging
Spectroscopic x-ray detectors, such as Medipix, are opening the door to the widespread use of energy
selective biomedical x-ray imaging. With dual energy computed tomography quickly becoming the clinical standard,
spectroscopic imaging is a likely next step. However to confirm the utility of spectroscopic x-ray detectors there needs
to be a clearer indication of the clinical benefits of the technology
Spectroscopic biomedical imaging with the Medipix2 detector
This study confirms that the Medipix2 x-ray detector enables spectroscopic bio-medical plain radiography. We show that
the detector has the potential to provide new, useful information beyond the limited spectroscopic information of modern
dual-energy computed tomography (CT) scanners. Full spectroscopic 3D-imaging is likely to be the next major
technological advance in computed tomography, moving the modality towards molecular imaging applications. This
paper focuses on the enabling technology which allows spectroscopic data collection and why this information is useful.
In this preliminary study we acquired the first spectroscopic images of human tissue and other biological samples
obtained using the Medipix2 detector. The images presented here include the clear resolution of the 1.4mm long distal
phalanx of a 20 week old miscarried foetus, showing clear energy-dependent variations. The opportunities for further
research using the forthcoming Medipix3 detector are discussed and a prototype spectroscopic CT scanner (MARS,
Medipix All Resolution System) is briefly described
Centralized Modularity of N-Linked Glycosylation Pathways in Mammalian Cells
Glycosylation is a highly complex process to produce a diverse repertoire of
cellular glycans that are attached to proteins and lipids. Glycans are involved
in fundamental biological processes, including protein folding and clearance,
cell proliferation and apoptosis, development, immune responses, and
pathogenesis. One of the major types of glycans, N-linked glycans, is formed by
sequential attachments of monosaccharides to proteins by a limited number of
enzymes. Many of these enzymes can accept multiple N-linked glycans as
substrates, thereby generating a large number of glycan intermediates and their
intermingled pathways. Motivated by the quantitative methods developed in
complex network research, we investigated the large-scale organization of such
N-linked glycosylation pathways in mammalian cells. The N-linked glycosylation
pathways are extremely modular, and are composed of cohesive topological
modules that directly branch from a common upstream pathway of glycan
synthesis. This unique structural property allows the glycan production between
modules to be controlled by the upstream region. Although the enzymes act on
multiple glycan substrates, indicating cross-talk between modules, the impact
of the cross-talk on the module-specific enhancement of glycan synthesis may be
confined within a moderate range by transcription-level control. The findings
of the present study provide experimentally-testable predictions for
glycosylation processes, and may be applicable to therapeutic glycoprotein
engineering
A review of information flow diagrammatic models for product-service systems
A product-service system (PSS) is a combination of products and services to
create value for both customers and manufacturers. Modelling a PSS based on
function orientation offers a useful way to distinguish system inputs and
outputs with regards to how data are consumed and information is used, i.e.
information flow. This article presents a review of diagrammatic information
flow tools, which are designed to describe a system through its functions. The
origin, concept and applications of these tools are investigated, followed by an
analysis of information flow modelling with regards to key PSS properties. A
case study of selection laser melting technology implemented as PSS will then be
used to show the application of information flow modelling for PSS design. A
discussion based on the usefulness of the tools in modelling the key elements of
PSS and possible future research directions are also presented
Multiplex Detection and SNP Genotyping in a Single Fluorescence Channel
Probe-based PCR is widely used for SNP (single nucleotide polymorphism) genotyping and pathogen nucleic acid detection due to its simplicity, sensitivity and cost-effectiveness. However, the multiplex capability of hydrolysis probe-based PCR is normally limited to one target (pathogen or allele) per fluorescence channel. Current fluorescence PCR machines typically have 4–6 channels. We present a strategy permitting the multiplex detection of multiple targets in a single detection channel. The technique is named Multiplex Probe Amplification (MPA). Polymorphisms of the CYP2C9 gene (cytochrome P450, family 2, subfamily C, polypeptide 9, CYP2C9*2) and human papillomavirus sequences HPV16, 18, 31, 52 and 59 were chosen as model targets for testing MPA. The allele status of the CYP2C9*2 determined by MPA was entirely concordant with the reference TaqMan® SNP Genotyping Assays. The four HPV strain sequences could be independently detected in a single fluorescence detection channel. The results validate the multiplex capacity, the simplicity and accuracy of MPA for SNP genotyping and multiplex detection using different probes labeled with the same fluorophore. The technique offers a new way to multiplex in a single detection channel of a closed-tube PCR
ACL reconstruction with unicondylar replacement in knee with functional instability and osteoarthritis
Severe symptomatic osteoarthritis in young and active patients with pre-existing deficiency of the anterior cruciate ligament and severe functionally instability is a difficult subgroup to manage. There is considerable debate regarding management of young patients with isolated unicompartment osteoarthritis and concomitant ACL deficiency. A retrospective analysis of was done in 9 patients with symptomatic osteoarthritis with ACL deficiencies and functional instability that were treated with unicompartment knee arthroplasty and ACL reconstruction between April 2002 and June 2005. The average arc of flexion was 119° (range 85° to 135°) preoperatively and 125° (range 105° to 140°). There were no signs of instability during the follow up of patients. No patients in this group were reoperated. In this small series we have shown that instability can be corrected and pain relieved by this combined procedure
Sex and Pubertal Differences in the Type 1 Interferon Pathway Associate With Both X Chromosome Number and Serum Sex Hormone Concentration
Type 1 interferons (IFN) are an antiviral cytokine family, important in juvenile onset systemic
lupus erythematosus (jSLE) which is more common in females, around puberty. We report
that plasmacytoid dendritic cells (pDC) from healthy females produced more type 1 IFN
after toll like receptor (TLR) 7 signaling than males, even before puberty, but that puberty
itself associated with increased production of type 1 IFN. A unique human model allows
us to show that this was related to X chromosome number, and serum testosterone
concentration, in a manner which differed depending on the number of X chromosomes
present. In addition, we have showed that pDC were more activated in females overall,
and immune cell TLR7 gene expression was higher in females after puberty. Therefore,
sex hormones and X chromosome number were associated individually and interactively
with the type 1 IFN response, which contributes to our understanding of why females
are more likely to develop an IFN mediated disease like jSLE after puberty
Writing materiality into management and organization studies through and with Luce Irigaray
YesThere is increasing recognition in management and organization studies of the
importance of materiality as an aspect of discourse, while the neglect of materiality in
post-structuralist management and organization theory is currently the subject of much
discussion. This article argues that this turn to materiality may further embed gender
discrimination. We draw on Luce Irigaray’s work to highlight the dangers inherent in
masculine discourses of materiality. We discuss Irigaray’s identification of how language
and discourse elevate the masculine over the feminine so as to offer insights into ways
of changing organizational language and discourses so that more beneficial, ethicallyfounded
identities, relationships and practices can emerge. We thus stress a political
intent that aims to liberate women and men from phallogocentrism. We finally take
forward Irigaray’s ideas to develop a feminist écriture of/for organization studies that
points towards ways of writing from the body. The article thus not only discusses how
inequalities may be embedded within the material turn, but it also provides a strategy
that enriches the possibilities of overcoming them from within
Patterns of sick-leave and health outcomes in injured workers with back pain
Little is known about the sick-leave experiences of workers who make a workers’ compensation claim for back pain. Our objective is to describe the 1-year patterns of sick-leave and the health outcomes of a cohort of workers who make a workers’ compensation claim for back pain. We studied a cohort of 1,831 workers from five large US firms who made incident workers’ compensation claims for back pain between January 1, 1999 and June 30, 2002. Injured workers were interviewed 1 month (n = 1,321), 6 months (n = 810) and 1 year (n = 462) following the onset of their pain. We described the course of back pain using four patterns of sick-leave: (1) no sick-leave, (2) returned to worked and stayed, (3) multiple episodes of sick-leave and (4) not yet returned to work. We described the health outcomes as back and/or leg pain intensity, functional limitations and health-related quality of life. We analyzed data from participants who completed all follow-up interviews (n = 457) to compute the probabilities of transition between patterns of sick-leave. A significant proportion of workers experienced multiple episodes of sick-leave (30.2%; 95% CI 25.0–35.1) during the 1-year follow-up. The proportion of workers who did not report sick-leave declined from 42.4% (95% CI 39.0–46.1) at 1 month to 33.6% (28.0–38.7) at 1 year. One year after the injury, 2.9% (1.6–4.9) of workers had not yet returned to work. Workers who did not report sick-leave and those who returned and stayed at work reported better health outcomes than workers who experienced multiple episodes of sick-leave or workers who had not returned to work. Almost a third of workers with an incident episode of back pain experience recurrent spells of work absenteeism during the following year. Our data suggest that stable patterns of sick-leave are associated with better health
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