Navigation of the TSS-1 mission

The Tethered Satellite System Mission was analyzed to determine its impacts on the Mission Control Center (MCC) Navigation section's ability to maintain an accurate state vector for the Space Shuttle during nominal and off-nominal flight operations. Tether dynamics expected on the Shuttle introduces new phenomena when determining the best estimation of its position and velocity. In the analysis, emphasis was placed on determining the navigation state vectors accuracies resulting when the tether induced forces were and were not modeled as an additional acceleration upon processing tracking measurements around a TSS-1 trajectory. Results of the analyses show that when the forces are not modeled in the state vector generation process, the resulting solution state reflects a solution about the center of gravity of the tethered system and not that of the orbiter. The Navigation team's ability to provide accurate state vector estimates necessary for trajectory planning are impeded. In addition to this consequent, is an impact on Onboard Navigation state vector accuracies. These analyses will show that in order to preserve an accurate state onboard the orbiter a new operational procedure would have to be adopted

Radiation therapy for neovascular age-related macular degeneration

Antivascular endothelial growth factor (anti-VEGF) therapies represent the standard of care for most patients presenting with neovascular (wet) age-related macular degeneration (neovascular AMD). Anti-VEGF drugs require repeated injections and impose a considerable burden of care, and not all patients respond. Radiation targets the proliferating cells that cause neovascular AMD, including fibroblastic, inflammatory, and endothelial cells. Two new neovascular AMD radiation treatments are being investigated: epimacular brachytherapy and stereotactic radiosurgery. Epimacular brachytherapy uses beta radiation, delivered to the lesion via a pars plana vitrectomy. Stereotactic radiosurgery uses low voltage X-rays in overlapping beams, directed onto the lesion. Feasibility data for epimacular brachytherapy show a greatly reduced need for anti-VEGF therapy, with a mean vision gain of 8.9 ETDRS letters at 12 months. Pivotal trials are underway (MERLOT, CABERNET). Preliminary stereotactic radiosurgery data suggest a mean vision gain of 8 to 10 ETDRS letters at 12 months. A large randomized sham controlled stereotactic radiosurgery feasibility study is underway (CLH002), with pivotal trials to follow. While it is too early to conclude on the safety and efficacy of epimacular brachytherapy and stereotactic radiosurgery, preliminary results are positive, and these suggest that radiation offers a more durable therapeutic effect than intraocular injections

SOUTHERNMOST OCCURRENCE OF THE SUWANNEE COOTER, PSEUDEMYS CONCINNA SUWANNIENSIS (TESTUDINES: EMYDIDAE)

The Suwannee Cooter, Pseudemys concinna suwanniensis, the largest member of the speciose turtle family Emydidae, inhabits a small number of rivers that drain into the northeastern Gulf of Mexico along the northwest coast of Florida from just west of Tallahassee to just south of Tampa. The status of this state-protected subspecies in the southernmost of these rivers, the Alafia, is unknown and hence of conservation concern. We provide recent evidence confirming that a reproducing population still exists in this river, and review available specimens and both published and unpublished records documenting the southern limit of distribution. At least within the eastern United States, our observations also extend confirmed knowledge of the geographic occurrence of hatchling turtles overwintering in the nest southward by 285 km

Reverse-engineering the cortical architecture for controlled semantic cognition.

We employ a reverse-engineering approach to illuminate the neurocomputational building blocks that combine to support controlled semantic cognition: the storage and context-appropriate use of conceptual knowledge. By systematically varying the structure of a computational model and assessing the functional consequences, we identified the architectural properties that best promote some core functions of the semantic system. Semantic cognition presents a challenging test case, as the brain must achieve two seemingly contradictory functions: abstracting context-invariant conceptual representations across time and modalities, while producing specific context-sensitive behaviours appropriate for the immediate task. These functions were best achieved in models possessing a single, deep multimodal hub with sparse connections from modality-specific regions, and control systems acting on peripheral rather than deep network layers. The reverse-engineered model provides a unifying account of core findings in the cognitive neuroscience of controlled semantic cognition, including evidence from anatomy, neuropsychology and functional brain imaging

Pension Accounting And Reporting With Other Comprehensive Income And Deferred Taxes: A Worksheet Approach

This instructional tool presents pension accounting using a worksheet approach where debits equal credits for both the employer and for the plan. Transactions associated with the initiation of the plan through the end of the second year of the plan are presented, including their impact on accumulated other comprehensive income and deferred taxes. This article is intended as a supplemental teaching tool that demonstrates the impact of a plan’s funded status on the employer’s financial statements in a way that, based upon anecdotal evidence, accounting students and practitioners have found extremely beneficial beyond traditional accounting textbooks

Benthic Macroinvertebrates as Indexes of Water Quality in the Upper Cuyahoga River

Author Institution: Department of Biology and Center for Environmental Studies, The University of AkronThe upper Cuyahoga River in northeastern Ohio is the major source of domestic water for the City of Akron, an important recreational area, and a designated Ohio Scenic River. Indexes of water quality based on benthic invertebrate community composition indicate a wide range in water quality along the river, but overall water quality is relatively high compared to areas of the Cuyahoga River below Akron and to most nearby river systems. Highest quality areas are located in the most headwater region and in the lowermost region near Lake Rockwell. These areas are characterized by a large number of taxa (>50), moderate density of organisms (= 2,000/m2), high ratios of scraper-grazers to detritivores (>0.5), high ratios of amphipods to isopods, and less than 1% organic pollution-tolerant organisms. Moderate degradation of water quality due to organic sedimentation in these areas is indicated by large proportions of organic pollution-facultative organisms (27-66%), especially a great variety of chironomids. Lowest quality areas occur 1-2 km below waste water outfalls from small villages and below groups of rural streamside dwellings. These areas are characterized by up to 62% fewer species, very low ratios of amphipods to isopods (usually <2), and large proportions of organic pollution-facultative and tolerant organisms (43-95%), especially chironomids and oligochaetes

DISTRIBUTION AND STATUS OF THE SUWANNEE COOTER, PSEUDEMYS CONCINNA SUWANNIENSIS, IN THE ALAFIA RIVER (HILLSBOROUGH COUNTY, FLORIDA, USA)

The Suwannee Cooter, Pseudemys concinna suwanniensis, is a geographically limited turtle of conservation concern that inhabits Florida rivers draining into the northeastern Gulf of Mexico. Threats impacting its conservation status include take for human consumption, predation of turtles and nests, loss or degradation of nesting and basking habitat, water quality degradation, and boat strikes. Our surveys revealed that the Alafia River, which drains into Hillsborough Bay (northeastern Tampa Bay), is likely the stronghold of the southern distribution of P. c. suwanniensis. Multiple survey methods during 2015-2020 revealed that a substantial population of Suwannee Cooters inhabits much of this blackwater river system, including the main channel and at least one of its two primary tributaries. GIS analysis showed that more than half of the shoreline within the occupied extent is currently protected by conservation lands, although additional protection of private lands and improved habitat management protocols are needed to assure the population’s conservation

Pars plana vitrectomy for diabetic macular edema: a systematic review, meta-analysis, and synthesis of safety literature

Purpose. To assess the risk and benefit of pars plana vitrectomy for diabetic macular edema (DME). Methods. We conducted a systematic literature review using PubMed, EMBASE, Web of Science, and Cochrane Central Database of Controlled Trials until September 2014. The population was patients with DME, intervention vitrectomy, comparator macular laser or observation, and efficacy outcome visual acuity and central retinal thickness (CRT). Safety outcomes were intra- and postoperative surgical complications. The efficacy meta-analysis included only randomized controlled trials. The safety analysis included prospective, retrospective, controlled and uncontrolled studies. Results. Five studies were eligible for the efficacy meta-analysis (n = 127 eyes) and 40 for the safety analysis (n = 1,562 eyes). Combining follow up intervals from 6 to 12 months, the meta-analysis found a non-significant 2 letter visual acuity difference favoring vitrectomy, and a significant 102 micron greater reduction in CRT favoring vitrectomy, but a post-hoc subgroup analysis found that a 6 month CRT benefit reversed by 12 months. The most frequent complications were retinal break (7.1%), elevated intraocular pressure (5.2%), epiretinal membrane (3.3%), and vitreous hemorrhage (2.4%). Cataract developed in 68.6% of 121 phakic eyes. Conclusions. Vitrectomy produces structural and functional improvements in select eyes with DME, but the visual gains are not significantly better than with laser or observation. No major safety concerns were identified