2,385 research outputs found
Esthesioneuroblastoma: Management of the N0 neck
Esthesioneuroblastoma is a rare sinonasal malignancy that arises from the olfactory epithelium. The overall incidence of lymph node metastases is 25%. However, neck disease can present in a delayed fashion. As such, management of the clinically negative neck is controversial, with some advocating for elective neck treatment and others recommending observation with salvage treatment if necessary. At this time, no prospective head-to-head comparisons of elective versus salvage treatment have been performed
Surgery groups of the fundamental groups of hyperplane arrangement complements
Using a recent result of Bartels and Lueck (arXiv:0901.0442) we deduce that
the Farrell-Jones Fibered Isomorphism conjecture in L-theory is true for any
group which contains a finite index strongly poly-free normal subgroup, in
particular, for the Artin full braid groups. As a consequence we explicitly
compute the surgery groups of the Artin pure braid groups. This is obtained as
a corollary to a computation of the surgery groups of a more general class of
groups, namely for the fundamental group of the complement of any fiber-type
hyperplane arrangement in the complex n-space.Comment: 11 pages, AMSLATEX file, revised following referee's comments and
suggestions, to appear in Archiv der Mathemati
Electron Holes and Heating in the Reconnection Dissipation Region
Using particle-in-cell simulations and kinetic theory, we explore the
current-driven turbulence and associated electron heating in the dissipation
region during 3D magnetic reconnection with a guide field. At late time the
turbulence is dominated by the Buneman and lower hybrid instabilities. Both
produce electron holes that co-exist but have very different propagation
speeds. The associated scattering of electrons by the holes enhances electron
heating in the dissipation region.Comment: 14 pages, 5 figures, submitted to GR
Strongly minimal PD4-complexes
We consider the homotopy types of -complexes with fundamental group
such that and has one end. Let
and . Our main result is that (modulo two technical conditions on
) there are at most orbits of -invariants determining
"strongly minimal" complexes (i.e., those with homotopy intersection pairing
trivial). The homotopy type of a -complex with a
-group is determined by , , and the -type of
. Our result also implies that Fox's 2-knot with metabelian group is
determined up to TOP isotopy and reflection by its group.Comment: 17 page
Parents' involvement in care order decisions: a cross-country study of front-line practice
This article examines parentsâ involvement in care order decision-making in four countries at one particular point in the care order process, namely when the child protection worker discusses with the parents his/her considerations regarding child removal. The countries represent different child welfare systems with Norway and Finland categorized as âfamily service systemsâ and the US as a âchild protection systemâ, with England somewhere in between. The focus is on whether the forms and intensity of involvement are different in these four countries, and whether the system orientation towards family services or child protection influences practice in the social welfare agencies with parents. Involvement is studied in terms of providing information to parents, collecting information from parents and ensuring inclusion in the decision-making processes. A vignette method is employed in a survey with 768 responses from child protection workers in four countries. The findings do not show a consistent pattern of difference regarding parental involvement in care order preparations that align with the type of child welfare system in which staff work. The goal in each child welfare system is to include parents, but the precise ways in which it is done (or not) vary. Methodological suggestions are given for further studies
A Label-Free Fiber Ring Laser Biosensor For Ultrahigh Sensitivity Detection of Salmonella Typhimurium
The rapid detection of low concentrations of Salmonella Typhimurium (S. Typhimurium) is an essential preventive measure for food safety and prevention of foodborne illness. The study presented in this paper addresses this critical issue by proposing a single mode-tapered seven core-single mode (STSS) fiber ring laser (FRL) biosensor for S. Typhimurium detection. The experimental results show that the specific detection time of S. Typhimurium is less than 20 min and the wavelength shift can achieve -0.906 nm for an S. Typhimurium solution (10 cells/mL). Furthermore, at a lower concentration of 1 cell/mL applied to the biosensor, a result of -0.183 nm is observed in 9% of samples (1/11), which indicates that the proposed FRL biosensor has the ability to detect 1 cell/mL of S. Typhimurium. In addition, the detection results in chicken and pickled pork samples present an average deviation of -27% and -23%, respectively, from the measured results in phosphate buffered saline. Taken together, these results show the proposed FRL biosensor may have potential applications in the fields of food safety monitoring, medical diagnostics, etc
The demand for sports and exercise: Results from an illustrative survey
Funding from the Department of Health policy research programme was used in this study.There is a paucity of empirical evidence on the extent to which price and perceived benefits affect the level of participation in sports and exercise. Using an illustrative sample of 60 adults at Brunel University, West London, we investigate the determinants of demand for sports and exercise. The data were collected through face-to-face interviews that covered indicators of sports and exercise behaviour; money/time price and perceived benefits of participation; and socio- economic/demographic details. Count, linear and probit regression models were fitted as appropriate. Seventy eight per cent of the sample participated in sports and exercise and spent an average of ÂŁ27 per month and an average of 20 min travelling per occasion of sports and exercise. The demand for sport and exercise was negatively associated with time (travel or access time) and âvariableâ price and positively correlated with âfixedâ price. Demand was price inelastic, except in the case of meeting the UK governmentâs recommended level of participation, which is time price elastic (elasticity = â2.2). The implications of data from a larger nationally representative sample as well as the role of economic incentives in influencing uptake of sports and exercise are discussed.This article is available through the Brunel Open Access Publishing Fund
Determining the Role of Surgery in Diagnosis and Treatment of Primary CNS Lymphoma
Introduction: Primary central nervous system lymphoma (PCNSL) is a rare entity typically treated with a combination of chemotherapy and radiation. The role of surgery is controversial, and biopsy may be non-definitive or injurious. We review our series of stereotactic and excisional biopsy as well as surgical debulking of PCNSL to quantify overall risk and benefits.
Methods: Patients with biopsy-confirmed intracranial PCNSL were identified from a large singlecenter academic institution between 2012-2018. Preoperative factors and perioperative outcomes were retrospectively reviewed.
Results: A total of 61 cases of PCNSL were identified. Most patients presented with confusion (23.0%), weakness/paralysis (19.7%), and gait disturbance (18.0%). 1.6% were incidentally identified. HIV status was positive in 8.2% of cases. CSF cytology was positive for malignancy in 33.3% of applicable cases. Of all procedures, 44.3% were needle biopsy, 27.9% were open excisional biopsies, and 27.9% were surgical debulking procedures. Prior biopsy had been performed in 9.8%, of which 83.3% (5/6) were positive for PCNSL. Intraoperative frozen pathology failed to illicit a definitive diagnosis in 39.3% of cases despite adequate sampling. Stereotactic biopsies did not demonstrate an increased risk of non-diagnostic frozen pathology compared to open excisional biopsy. Intraoperative complications, 30-day mortality, and long-term survival was not associated with open vs. stereotactic biopsy.
Discussion: Biopsy of PCNSL carries a moderate surgical risk that should not be discounted, particularly in the setting of previously diagnosed PCNSL or with evidence of malignancy in CSF cytology. Early initiation of chemotherapy continues to be the mainstay of long-term response and control
Development and initial testing of normal reference MR images for the brain at ages 65-70 and 75-80 years
Agency and social construction: practice of the self in art and design
Learning in the arts has the potential to be a co-constructive means of inquiry for students, which enables experience of the self in relation to practice. This research explores a practice-based investigation of agency as self-definition, amid normative social constructions of the subject. The focus for data analysis is a project taught to BTEC Level 2 Art and Design students in a deprived area of North London (2010-12). A dialogue is presented between the implications for Sartreâs theory of free-will and a Foucauldian critique of social construction. Applications for this comparative theory are discussed here as a form of resistance to the compression of learning identities in Art and Design, and across the curriculum. This is an approach which encourages emancipated self- representation, acknowledging cultural diversity, for a discursive environment viable at all levels of study. In exploring the data, a positioning of free-will with social responsibility is identified as an inclusive forum for creative understanding, and the tolerance of difference
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