3,514 research outputs found
Expanding the use of real-time electromagnetic tracking in radiation oncology.
In the past 10 years, techniques to improve radiotherapy delivery, such as intensity-modulated radiation therapy (IMRT), image-guided radiation therapy (IGRT) for both inter- and intrafraction tumor localization, and hypofractionated delivery techniques such as stereotactic body radiation therapy (SBRT), have evolved tremendously. This review article focuses on only one part of that evolution, electromagnetic tracking in radiation therapy. Electromagnetic tracking is still a growing technology in radiation oncology and, as such, the clinical applications are limited, the expense is high, and the reimbursement is insufficient to cover these costs. At the same time, current experience with electromagnetic tracking applied to various clinical tumor sites indicates that the potential benefits of electromagnetic tracking could be significant for patients receiving radiation therapy. Daily use of these tracking systems is minimally invasive and delivers no additional ionizing radiation to the patient, and these systems can provide explicit tumor motion data. Although there are a number of technical and fiscal issues that need to be addressed, electromagnetic tracking systems are expected to play a continued role in improving the precision of radiation delivery
Enhancement and suppression effects resulting from information structuring in sentences
Information structuring through the use of cleft sentences increases the processing efficiency of references to elements within the scope of focus. Furthermore, there is evidence that putting certain types of emphasis on individual words not only enhances their subsequent processing, but also protects these words from becoming suppressed in the wake of subsequent information, suggesting mechanisms of enhancement and suppression. In Experiment 1, we showed that clefted constructions facilitate the integration of subsequent sentences that make reference to elements within the scope of focus, and that they decrease the efficiency with reference to elements outside of the scope of focus. In Experiment 2, using an auditory text-change-detection paradigm, we showed that focus has similar effects on the strength of memory representations. These results add to the evidence for enhancement and suppression as mechanisms of sentence processing and clarify that the effects occur within sentences having a marked focus structure
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Interplay of Staphylococcal and Host Proteases Promotes Skin Barrier Disruption in Netherton Syndrome.
Netherton syndrome (NS) is a monogenic skin disease resulting from loss of function of lymphoepithelial Kazal-type-related protease inhibitor (LEKTI-1). In this study we examine if bacteria residing on the skin are influenced by the loss of LEKTI-1 and if interaction between this human gene and resident bacteria contributes to skin disease. Shotgun sequencing of the skin microbiome demonstrates that lesional skin of NS subjects is dominated by Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis). Isolates of either species from NS subjects are able to induce skin inflammation and barrier damage on mice. These microbes promote skin inflammation in the setting of LEKTI-1 deficiency due to excess proteolytic activity promoted by S. aureus phenol-soluble modulin α as well as increased bacterial proteases staphopain A and B from S. aureus or EcpA from S. epidermidis. These findings demonstrate the critical need for maintaining homeostasis of host and microbial proteases to prevent a human skin disease
A Survey of Ramp and Stair Use among Older Adults
Forty-three community-dwelling adults aged 57 to 95 participated in survey exploring characteristics of ramp use by older ambulant people. Twenty-three respondents said they ascended ramps instead of stairs most of the time, and 14 said they ascended ramps some of the time. Similar numbers were reported for descent. Overall, respondents felt less fatigued, less likely to trip, and more comfortable when using ramps rather than stairs for ascending one level. When descending one level, balance, tripping, and comfort were the strongest determinants of ramp use. Respondents indicated that descent was more problematic, particularly in regard to balance and tripping. The presence of handrails often determined the choice of route. Results from this survey provided the basis for an experiment evaluating the abilities of older people to traverse ramps of various slopes. The ADA Accessibility Guidelines implicitly assume that a ramp accommodates everyone. This study indicates that entrances should have both ramps and stairs.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Orbital dynamics of Cygnus X-3
Orbital-phased-resolved infrared spectra of Cygnus X-3 in outburst and
quiescence, including tomographic analysis, are presented. We confirm the
phasing of broad HeII and NV lines in quiescence, such that maximum blue shift
corresponds to the X-ray minimum at phase = 0.00 +/- 0.04. In outburst,
double-peaked HeI structures show a similar phasing with two significant
differences: (a) although varying in relative strength, there is continuous
line emission in blue and red peaks around the orbit, and (b) an absorption
component, ~1/4 of an orbit out of phase with the emission features, is
discerned. Doppler tomograms of the double-peaked profiles are consistent with
a disk-wind geometry, rotating at velocities of 1000 km/s. Regrettably, the
tomography algorithm will produce a similar ring structure from alternative
line sources if contaminated by overlying P Cygni profiles. This is certainly
the case in the strong 2.0587 micron HeI line, leading to an ambiguous solution
for the nature of double-peaked emission. The absorption feature, detected 1/4
of an orbit out of phase with the emission features, is consistent with an
origin in the He star wind and yields for the first time a plausible radial
velocity curve for the system. We directly derive the mass function of the
system, 0.027 M_sun. If we assume a neutron star accretor and adopt a high
orbital inclination, i > 60 degrees, we obtain a mass range for the He star of
5 M_sun < M_WR < 11 M_sun. Alternatively if the compact object is a black hole,
we estimate M_BH < 10 M_sun. We discuss the implications of these masses for
the nature and size of the binary system.Comment: Accepted for publication in ApJ main journa
Note and Comment
Safeguarding the Criminal Defendant - Every now and then a new attack is made somewhere in the United States upon the rule prohibiting comment before the jury upon the fact that the defendant in a criminal case has not testified as a witness in his own behalf. At the present time an effort of this kind is being made in the Michigan legislature, and the introduction of the bill drew quite a little storm of protest from the State press as a dangerous inroad upon our ancient guarantees of personal liberty and security. In fact, however, it directly touches nothing more ancient than a statutory privilege which dates from the year i86i. By the Public Acts of that year the disability of parties to actions to testify as witnesses in this State was removed, but it was expressly provided that defendants in criminal cases could not be compelled to testify, but might do so or not at their own pleasure. (Act No. 125, §2). In 1881 an amendment to this statute was passed providing, as to the defendant in a criminal case, that his neglect to testify shall not create any presumption against him, nor shall the court permit any reference or comment to be made to or upon such neglect. (Pub. Acts, 188I, No. 245). And this is the form it retains in the Judicature Act. (Ch. 17, §64)
The Importance of Organic Content to Fractal Floc Properties in Estuarine Surface Waters: Insights From Video, LISST, and Pump Sampling
To better understand the nature of flocs of varying organic content in estuarine surface waters, Laser in situ Scattering and Transmissometry, video settling, and pump sampling were deployed in the York River estuary. A new in situ method was developed to simultaneously solve the floc fractal dimension (F), primary particle size (d p ), and primary particle density (ρ p ) by fitting a simple fractal model to observations of effective floc density (∆ρ) as a function of floc diameter (d f ), while ensuring that the integrated particle size distribution was consistent with measurements of bulk apparent density (ρ a ). When fractal fits were statistically justified, application of the above methods showed the bulk fraction of organic matter (f org ) to be well correlated to multiple floc properties. As f org increased, d p and ρ a also increased, while ρ p , total suspended solids (TSS), and median floc size decreased. Notably for microflocs, neither F nor ∆ρ was significantly related to either f org or TSS. This indicates that organic matter may partially displace water content within microflocs without fundamentally changing the flocs’ inorganic structure. When pooling multiple samples, a marked decrease in F was seen at the transition to macroflocs, and most strongly for high f org cases. This suggested that settling velocities \u3e_ ~1 mm/s may produce turbulent stresses that tend to tear macroflocs apart. This study also found that when the fractal theory held, ρ p had a near 1:1 correlation with the bulk dry density of filtered TSS, implying that primary particles are tightly bound aggregates of combined mineral and organic component
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Cost Estimating for Decommissioning of a Plutonium Facility--Lessons Learned From The Rocky Flats Building 771 Project
The Rocky Flats Closure Site is implementing an aggressive approach in an attempt to complete Site closure by 2006. The replanning effort to meet this goal required that the life-cycle decommissioning effort for the Site and for the major individual facilities be reexamined in detail. As part of the overall effort, the cost estimate for the Building 771 decommissioning project was revised to incorporate both actual cost data from a recently-completed similar project and detailed planning for all activities. This paper provides a brief overview of the replanning process and the original estimate, and then discusses the modifications to that estimate to reflect new data, methods, and planning rigor. It provides the new work breakdown structure and discusses the reasons for the final arrangement chosen. It follows with the process used to assign scope, cost, and schedule elements within the new structure, and development of the new code of accounts. Finally, it describes the project control methodology used to track the project, and provides lessons learned on cost tracking in the decommissioning environment
Aeronautic Instruments. Section IV : Direction Instruments
Part one points out the adequacy of a consideration of the steady state gyroscopic motion as a basis for the discussion of displacements of the gyroscope mounted on an airplane, and develops a simple theory on this basis. Principal types of gyroscopic inclinometers are described and requirements stated. Part two describes a new type of stabilizing gyro mounted on top of a spindle by means of a universal joint, the spindle being kept in a vertical position by supporting it as a pendulum of which the bob is the driving motor. Methods of tests and the difficulties in designing a satisfactory and reliable compass for aircraft use in considered in part three. Part four contains a brief general treatment of the important features of construction of aircraft compasses and description of the principal types used
Deploying Big Data To Crack The Genotype To Phenotype Code
Mechanistically connecting genotypes to phenotypes is a longstanding and central mission of biology. Deciphering these connections will unite questions and datasets across all scales from molecules to ecosystems. Although high-throughput sequencing has provided a rich platform on which to launch this effort, tools for deciphering mechanisms further along the genome to phenome pipeline remain limited. Machine learning approaches and other emerging computational tools hold the promise of augmenting human efforts to overcome these obstacles. This vision paper is the result of a Reintegrating Biology Workshop, bringing together the perspectives of integrative and comparative biologists to survey challenges and opportunities in cracking the genotype to phenotype code and thereby generating predictive frameworks across biological scales. Key recommendations include: promoting the development of minimum “best practices” for the experimental design and collection of data; fostering sustained and long-term data repositories; promoting programs that recruit, train, and retain a diversity of talent and providing funding to effectively support these highly cross-disciplinary efforts. We follow this discussion by highlighting a few specific transformative research opportunities that will be advanced by these efforts
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