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Performance benefits of telerobotics and teleoperation - enhancements for an arm-based tank waste retrieval system
This report evaluates telerobotic and teleoperational arm-based retrieval systems that require advanced robotic controls. These systems will be deployed in waste retrieval activities in Hanford`s Single Shell Tanks (SSTs). The report assumes that arm-based, retrieval systems will combine a teleoperational arm and control system enhanced by a number of advanced and telerobotic controls. The report describes many possible enhancements, spanning the full range of the control spectrum with the potential for technical maturation. The enhancements considered present a variety of choices and factors including: the enhancements to be included in the actual control system, safety, detailed task analyses, human factors, cost-benefit ratios, and availability and maturity of technology. Because the actual system will be designed by an offsite vendor, the procurement specifications must have the flexibility to allow bidders to propose a broad range of ideas, yet build in enough restrictions to filter out infeasible and undesirable approaches. At the same time they must allow selection of a technically promising proposal. Based on a preliminary analysis of the waste retrieval task, and considering factors such as operator limitations and the current state of robotics technology, the authors recommend a set of enhancements that will (1) allow the system to complete its waste retrieval mission, and (2) enable future upgrades in response to changing mission needs and technological advances
Static intervortex forces
A point particle approximation to the classical dynamics of well separated
vortices of the abelian Higgs model is developed. A static vortex is
asymptotically identical to a solution of the linearized field theory (a
Klein-Gordon/Proca theory) in the presence of a singular point source at the
vortex centre. It is shown that this source is a composite scalar monopole and
magnetic dipole, and the respective charges are determined numerically for
various values of the coupling constant. The interaction potential of two well
separated vortices is computed by calculating the interaction Lagrangian of two
such point sources in the linear theory. The potential is used to model type II
vortex scattering.Comment: Much shorter (10 pages) published version, new titl
Evaluacija inovativno digitalno kontroliranog Er:YAG lasera u lijeÄŤenju leukoplakije - probno istraĹľivanje
The use of lasers for treatment of oral leukoplakia has gained a lot of interest in the past years, however, data on the use of Er:YAG laser are scarce. The aim of this study was to compare the efficacy of Er:YAG laser and 1% topical isotretinoin in the treatment of 27 oral leukoplakia patients. Er:YAG laser (LightWalker AT, Fotona, Slovenia) was used in 27 patients with 27 leukoplakia lesions. Postoperative pain was assessed by use of visual analog scale (VAS), and the impact of laser treatment on the quality of life was assessed by the OHIP-14 questionnaire (Croatian version). Control group consisted of the same 27 patients previously treated with 1% topical isotretionin three times a day during the period of one year. No improvement in the size of leukoplakia lesions was observed after treatment with topical isotretinoin. There were significant differences between men and women according to leukoplakia localization, number of laser sessions and VAS (p<0.05). At follow-up after six months and one year, there was no recurrence of lesions. Er:YAG laser is a successful treatment for oral leukoplakia. Topical isotretionin treatment is unsuccessful in patients with oral leukoplakia.Posljednjih godina postoji veliko zanimanje za upotrebu lasera u liječenju oralne leukoplakije, ali su podatci o upotrebi Er:YAG lasera malobrojni. Cilj ovoga istraživanja bio je usporediti učinak Er:YAG lasera i 1%-tnog topikalnog izotretinoina u liječenju 27 bolesnika s oralnom leukoplakijom. Er:YAG laser (LightWalker AT, Fotona, Slovenia) je korišten u 27 bolesnika s 27 leukoplakičnih lezija. Poslijeoperacijska bol je određena uz pomoć vizualne analogne ljestvice (visual analog scale,
VAS), a utjecaj na kvalitetu života mjeren je pomoću upitnika OHIP-14 (hrvatska verzija). Kontrolna skupina se sastojala od istih 27 bolesnika koji su prije toga liječeni 1%-tnim topikalnim izotretioninom tri puta na dan tijekom tri mjeseca. Nije bilo poboljšanja u veličini lezija leukoplakije nakon topikalno primijenjenog izotretinoina. Utvrđene su značajne razlike između muškaraca i žena s obzirom na lokalizaciju leukoplakije, broj laserskih zahvata i rezultata VAS (p<0,05). Šest mjeseci i godinu dana od laserskog zahvata nije bilo recidiva oralne leukoplakije. Er:YAG laser je uspješna terapija u liječenju oralne leukoplakije. Topikalna primjena izotretionina nije uspješna u liječenju oralne leukoplakije
On Physical Equivalence between Nonlinear Gravity Theories
We argue that in a nonlinear gravity theory, which according to well-known
results is dynamically equivalent to a self-gravitating scalar field in General
Relativity, the true physical variables are exactly those which describe the
equivalent general-relativistic model (these variables are known as Einstein
frame). Whenever such variables cannot be defined, there are strong indications
that the original theory is unphysical. We explicitly show how to map, in the
presence of matter, the Jordan frame to the Einstein one and backwards. We
study energetics for asymptotically flat solutions. This is based on the
second-order dynamics obtained, without changing the metric, by the use of a
Helmholtz Lagrangian. We prove for a large class of these Lagrangians that the
ADM energy is positive for solutions close to flat space. The proof of this
Positive Energy Theorem relies on the existence of the Einstein frame, since in
the (Helmholtz--)Jordan frame the Dominant Energy Condition does not hold and
the field variables are unrelated to the total energy of the system.Comment: 37 pp., TO-JLL-P 3/93 Dec 199
Report of the National Heart, Lung, and Blood Institute Working Group on epigenetics and hypertension
Hypertension, defined as a condition associated with 65140-mm Hg systolic blood pressure or 6590-mm Hg diastolic blood pressure, affects >1 billion people worldwide,1 and in 2009 it cost the US healthcare system more than 3.6 trillion more over the next 10 years.
SARS-CoV-2-specific nasal IgA wanes 9 months after hospitalisation with COVID-19 and is not induced by subsequent vaccination
BACKGROUND: Most studies of immunity to SARS-CoV-2 focus on circulating antibody, giving limited insights into mucosal defences that prevent viral replication and onward transmission. We studied nasal and plasma antibody responses one year after hospitalisation for COVID-19, including a period when SARS-CoV-2 vaccination was introduced. METHODS: In this follow up study, plasma and nasosorption samples were prospectively collected from 446 adults hospitalised for COVID-19 between February 2020 and March 2021 via the ISARIC4C and PHOSP-COVID consortia. IgA and IgG responses to NP and S of ancestral SARS-CoV-2, Delta and Omicron (BA.1) variants were measured by electrochemiluminescence and compared with plasma neutralisation data. FINDINGS: Strong and consistent nasal anti-NP and anti-S IgA responses were demonstrated, which remained elevated for nine months (p < 0.0001). Nasal and plasma anti-S IgG remained elevated for at least 12 months (p < 0.0001) with plasma neutralising titres that were raised against all variants compared to controls (p < 0.0001). Of 323 with complete data, 307 were vaccinated between 6 and 12 months; coinciding with rises in nasal and plasma IgA and IgG anti-S titres for all SARS-CoV-2 variants, although the change in nasal IgA was minimal (1.46-fold change after 10 months, p = 0.011) and the median remained below the positive threshold determined by pre-pandemic controls. Samples 12 months after admission showed no association between nasal IgA and plasma IgG anti-S responses (R = 0.05, p = 0.18), indicating that nasal IgA responses are distinct from those in plasma and minimally boosted by vaccination. INTERPRETATION: The decline in nasal IgA responses 9 months after infection and minimal impact of subsequent vaccination may explain the lack of long-lasting nasal defence against reinfection and the limited effects of vaccination on transmission. These findings highlight the need to develop vaccines that enhance nasal immunity. FUNDING: This study has been supported by ISARIC4C and PHOSP-COVID consortia. ISARIC4C is supported by grants from the National Institute for Health and Care Research and the Medical Research Council. Liverpool Experimental Cancer Medicine Centre provided infrastructure support for this research. The PHOSP-COVD study is jointly funded by UK Research and Innovation and National Institute of Health and Care Research. The funders were not involved in the study design, interpretation of data or the writing of this manuscript
Informality in organization and research : a review and a proposal
The growing interest in informal and emergent features of organizations has
accompanied changes both in the dominant forms of organization and prevailing
academic views about how best to think about and research them. It is argued here
that currently espoused dichotomous characterizations of both organizations and
research approaches are over-simplified and misleading.
A review of types of organisation research is conducted and it is suggested that the
relationship between theory and data collection provides a more detailed and
illuminating taxonomy than a distinction between qualitative and quantitative
research. Two major distinctions are proposed: [1] between theory driven and
phenomenon driven research; [2] between descriptive and prescriptive theory. It is
suggested that organization theory is properly prescriptive in nature.
The place of informality in organization and management studies is explicated,
drawing on insights from Wittgenstein and ethnomethodology (EM). A distinction is
drawn between [1] the degree of formality in particular organizational settings and [2]
the necessarily informal foundations of formal organizational schemes and methods.
Finally, the organization of research itself is addressed. A prescriptive theory (TFV)
is suggested as a means of organizing and accounting for the research process. This
suggestion serves as both [1] a proposal for research management and [2] an
illustration of the relationship between theory and organization