Constraints on the Hubble constant from supernova Refsdal's reappearance.

The gravitationally lensed supernova Refsdal appeared in multiple images produced through gravitational lensing by a massive foreground galaxy cluster. After the supernova appeared in 2014, lens models of the galaxy cluster predicted that an additional image of the supernova would appear in 2015, which was subsequently observed. We use the time delays between the images to perform a blinded measurement of the expansion rate of the Universe, quantified by the Hubble constant (H0). Using eight cluster lens models, we infer [Formula: see text]. Using the two models most consistent with the observations, we find [Formula: see text]. The observations are best reproduced by models that assign dark-matter halos to individual galaxies and the overall cluster.

Choosing a Graft for Anterior Cruciate Ligament Reconstruction: Surgeon Influence Reigns Supreme.

Selection of a graft type is an important decision for patients undergoing reconstructive surgery for a ligamentous injury. The purpose of this study was to determine the weight of key factors affecting patient selection of graft type for anterior cruciate ligament (ACL) reconstruction and to assess patients' knowledge of their particular graft type. We prospectively enrolled 304 patients who underwent primary ACL reconstruction. Patients filled out questionnaires at their first follow-up appointment after surgery and at least 1 year postoperatively. Questionnaires asked which type of graft was used and why they chose that graft. At their first postoperative appointment, 88% of autograft patients and 71% of allograft patients were accurate in stating their graft type and harvest location. The most common factor influencing graft selection was physician recommendation (81.6%). At the time of follow-up, 96% of patients were satisfied with their graft choice. There is a high rate of accuracy with which patients remember the type of graft used for their ACL reconstruction. The majority of patients undergoing ACL reconstruction are primarily influenced by the physician's recommendation.

Economic analysis of athletic team coverage by an orthopedic practice.

OBJECTIVE: Coverage of high school football by orthopedic sports medicine specialists is considered standard of care in many localities. Determining the economic viability of this endeavor has never been investigated. The primary purpose of the present investigation was to perform an economic analysis of local high school sports coverage by an orthopedic sports medicine practice. METHODS: From January 2010 to June 2012, a prospective injury report database was used to collect sports injuries from five high school athletic programs covered by a single, private orthopedic sports medicine practice. Patients referred for orthopedic care were then tracked to determine expected cost of care (potential revenue). Evaluation and management codes and current procedure terminology codes were obtained to determine the value of physician visits and surgical care rendered. Overhead costs were calculated based on historical rates within our practice and incorporated to determine estimated profit. RESULTS: 19,165 athletic trainer contacts with athletes playing all sports, including both those 'on-field' and in the training room, resulted in 473 (2.5%) physician referrals. The covering orthopedic practice handled 89 (27.9%) of the orthopedic referrals. Of orthopedic physician referrals, 26 (5.4%) required orthopedic surgical treatment. The covering team practice handled 17/26 (65%) surgical cases. The total revenue collected by the covering team practice was $26,226.14. The overhead cost of treatment was $9441.41. Overall estimated profit of orthopedic visits and treatment during this period for the covering practice was $16,784.73. CONCLUSIONS: The covering team practice handled 28% of the orthopedic referrals, 65% of the surgical cases and captured 59% of the potential profit. An increase in physician referrals could increase the benefit for orthopedic surgeons.

No signature of ejecta interaction with a stellar companion in three type Ia supernovae.

Type Ia supernovae are thought to be the result of a thermonuclear runaway in carbon/oxygen white dwarfs, but it is uncertain whether the explosion is triggered by accretion from a non-degenerate companion star or by a merger with another white dwarf. Observations of a supernova immediately following the explosion provide unique information on the distribution of ejected material and the progenitor system. Models predict that the interaction of supernova ejecta with a companion star or circumstellar debris lead to a sudden brightening lasting from hours to days. Here we present data for three supernovae that are likely to be type Ia observed during the Kepler mission with a time resolution of 30 minutes. We find no signatures of the supernova ejecta interacting with nearby companions. The lack of observable interaction signatures is consistent with the idea that these three supernovae resulted from the merger of binary white dwarfs or other compact stars such as helium stars.

Memory CD8 T cell responses exceeding a large but definable threshold provide long-term immunity to malaria.

Infection of mice with sporozoites of Plasmodium berghei or Plasmodium yoelii has been used extensively to evaluate liver-stage protection by candidate preerythrocytic malaria vaccines. Unfortunately, repeated success of such vaccines in mice has not translated readily to effective malaria vaccines in humans. Thus, mice may be used better as models to dissect basic parameters required for immunity to Plasmodium-infection than as preclinical vaccine models. In turn, this basic information may aid in the rational design of malaria vaccines. Here, we describe a model of circumsporozoite-specific memory CD8 T cell generation that protects mice against multiple P. berghei sporozoite challenges for at least 19 months. Using this model we defined a threshold frequency of memory CD8 T cells in the blood that predicts long-term sterilizing immunity against liver-stage infection. Importantly, the number of Plasmodium-specific memory CD8 T cells required for immunity greatly exceeds the number required for resistance to other pathogens. In addition, this model allowed us to identify readily individual immunized mice that exceed or fall below the protective threshold before infection, information that should greatly facilitate studies to dissect basic mechanisms of protective CD8 T cell memory against liver-stage Plasmodium infection. Furthermore, the extremely large threshold in memory CD8 T cell frequencies required for long-term protection in mice may have important implications for development of effective malaria vaccines.

A web-based relational database for monitoring and analyzing mosquito population dynamics.

Mosquito population dynamics have been monitored on an annual basis in the state of Iowa since 1969. The primary goal of this project was to integrate light trap data from these efforts into a centralized back-end database and interactive website that is available through the internet at http://iowa-mosquito.ent.iastate.edu. For comparative purposes, all data were categorized according to the week of the year and normalized according to the number of traps running. Users can readily view current, weekly mosquito abundance compared with data from previous years. Additional interactive capabilities facilitate analyses of the data based on mosquito species, distribution, or a time frame of interest. All data can be viewed in graphical and tabular format and can be downloaded to a comma separated value (CSV) file for import into a spreadsheet or more specialized statistical software package. Having this long-term dataset in a centralized database/website is useful for informing mosquito and mosquito-borne disease control and for exploring the ecology of the species represented therein. In addition to mosquito population dynamics, this database is available as a standardized platform that could be modified and applied to a multitude of projects that involve repeated collection of observational data. The development and implementation of this tool provides capacity for the user to mine data from standard spreadsheets into a relational database and then view and query the data in an interactive website.

Landscape, demographic, entomological, and climatic associations with human disease incidence of West Nile virus in the state of Iowa, USA.

BACKGROUND: West Nile virus (WNV) emerged as a threat to public and veterinary health in the Midwest United States in 2001 and continues to cause significant morbidity and mortality annually. To investigate biotic and abiotic factors associated with disease incidence, cases of reported human disease caused by West Nile virus (WNV) in the state of Iowa were aggregated by census block groups in Iowa for the years 2002-2006. Spatially explicit data on landscape, demographic, and climatic conditions were collated and analyzed by census block groups. Statistical tests of differences between means and distributions of landscape, demographic, and climatic variables for census block groups with and without WNV disease incidence were carried out. Entomological data from Iowa were considered at the state level to add context to the potential ecological events taking place. RESULTS: Numerous statistically significant differences were shown in the means and distributions of various landscape and demographic variables for census block groups with and without WNV disease incidence. Census block groups with WNV disease incidence had significantly lower population densities than those without. Landscape variables showing differences included stream density, road density, land cover compositions, presence of irrigation, and presence of animal feeding operations. Statistically significant differences in the annual means of precipitations, dew point, and minimum temperature for both the year of WNV disease incidence and the prior year, were detected in at least one year of the analysis for each parameter. However, the differences were not consistent between years. CONCLUSION: The analysis of human WNV disease incidence by census block groups in Iowa demonstrated unique landscape, demographic, and climatic associations. Our results indicate that multiple ecological WNV transmission dynamics are most likely taking place in Iowa. In 2003 and 2006, drier conditions were associated with WNV disease incidence. In a significant novel finding, rural agricultural settings were shown to be strongly associated with human WNV disease incidence in Iowa.

Mosquito larvicidal activity of botanical-based mosquito repellents.

The larvicidal activity of 4 plant essential oils--innamon oil, lemon eucalyptus oil, sandalwood oil, and turmeric oil--previously reported as insect repellents was evaluated in the laboratory against 4th instars of Aedes albopictus, Ae. aegypti, and Culex pipiens. Sandalwood oil appeared to be the most effective of the larvicides, killing larvae of all 3 mosquito species in relatively short times. The values of LT50 and LT90 at the application dosage (0.2 mg/ml) were 1.06 +/- 0.11 and 3.24 +/- 0.14 h for Ae. aegypti, 1.82 +/- 0.06 and 3.33 +/- 0.48 h for Ae. albopictus, and 1.55 +/- 0.07 and 3.91 +/- 0.44 h for Cx. pipiens, respectively. Chemical compositions of these essential oils were also studied, and the lavicidal activity of their major ingredient compounds was compared with that of each of the essential oils. The acute toxicity of the 4 essential oils to fathead minnows was also evaluated. The safe use of these natural plant essential oils in future applications of mosquito control was discussed.

Fox squirrels (Sciurus niger) develop West Nile virus viremias sufficient for infecting select mosquito species.

The West Nile virus (WNV) viremia and shedding profiles of 11 adult fox squirrels (Sciurus niger) infected by needle inoculation or mosquito bite were characterized. Daily mean titers (95% confidence intervals) for all squirrels on days 1 through 6 postexposure (p.e.) were: 10(1.7 (1.32.1)), 10(4.4 (4.04.8)), 10(5.3 (5.05.6)), 10(4.4 (3.94.9)), 10(2.7 (2.03.4)), and 10(1.1 (0.52.1)) plaque-forming units (PFU)/mL. The highest WNV serum titers of individual squirrels infected by needle inoculation or mosquito bite ranged from 10(4.5) to 10(6.1) and from 10(5.1) to 10(5.3) PFU/mL, respectively. Nine (82%) squirrels, including all 4 squirrels infected by mosquito bite, had WNV serum titers > or =10(5.1) PFU/mL that persisted on average for 1.6 +/- 0.3 days. Infection and dissemination rates of Culex pipiens (L.) that fed on squirrels with serum titers of 10(4.4 +/- 0.1) PFU/mL were 56% and 13%, respectively. Both of these rates increased to over 80% when fed on squirrels with a mean WNV titer of 10(5.5 +/- 0.1) PFU/mL. Infection and dissemination also occurred in Aedes triseriatus (Say) but at a much lower rate. WNV was isolated from the oral and rectal cavities of all squirrels and from urine that was opportunistically collected from 5 squirrels. The largest quantity of WNV recovered from swabs of the oral cavity and urine was 10(3.1) PFU. The longest periods after exposure that WNV was isolated from the oral cavity and urine from a squirrel were 22 and 17 days p.e., respectively. WNV RNA was also detected in kidney tissue in 1 squirrel 29 days p.e., suggesting that fox squirrels can be persistently infected. Collectively these observations provide further evidence that squirrels can contribute to the natural history and epidemiology of WNV, especially in peridomestic environments.

Adult repellency and larvicidal activity of five plant essential oils against mosquitoes.

The larvicidal activity and repellency of 5 plant essential oils--thyme oil, catnip oil, amyris oil, eucalyptus oil, and cinnamon oil--were tested against 3 mosquito species: Aedes albopictus, Ae. aegypti, and Culex pipiens pallens. Larvicidal activity of these essentials oils was evaluated in the laboratory against 4th instars of each of the 3 mosquito species, and amyris oil demonstrated the greatest inhibitory effect with LC50 values in 24 h of 58 microg/ml (LC90 = 72 microg/ml) for Ae. aegypti, 78 microg/ml (LC90 = 130 microg/ml) for Ae. albopictus, and 77 microg/ml (LC90 = 123 microg/ml) for Cx. p. pallens. The topical repellency of these selected essential oils and deet against laboratory-reared female blood-starved Ae. albopictus was examined. Catnip oil seemed to be the most effective and provided 6-h protection at both concentrations tested (23 and 468 microg/ cm2). Thyme oil had the highest effectiveness in repelling this species, but the repellency duration was only 2 h. The applications using these natural product essential oils in mosquito control are discussed.

Eastern cottontail rabbits (Sylvilagus floridanus) develop West Nile virus viremias sufficient for infecting select mosquito species.

The potential of the eastern cottontail rabbit (CTR; Sylvilagus floridanus) to contribute to an enzootic West Nile virus (WNV) cycle was demonstrated by characterizing the WNV viremia profile of 15 CTRs and demonstrating that mosquitoes could become infected by feeding on these CTRs. Eight CTRs were infected with a titer of 10(5.0) cell-infectious dose 50% endpoints (CID50s) of WNV (NY99-Crow) by needle and seven CTRs by bite of one or more WNV-infected mosquitoes. There were no marked differences between the WNV viremia profiles of CTRs infected by either method. West Nile virus was detected in serums of all CTRs by 24 h p.i. The daily mean titers of all 15 CTRs on days 1-4 p.i. were 10(4.1+/-0.4), 10(4.7+/-0.3), 10(4.1+/-0.6), and 10(3.7+/-0.6) respectively, declining to 10(1.2+/-0.1) CID50s/ml of serum by day 6 p.i. No virus was detected in the blood of any CTR on day 7 p.i. The average duration of WNV titers of >or=10(4.3) and <10(5.0) CID50s/mL for all CTRs was 2.2 +/- 0.6 and 1.0 +/- 0.1 days, respectively. The minimum estimated infection rates (MEIRs) of Culex pipiens (L.) and Culex salinarius (Coq.) that fed on CTRs with titers of >or=10(4.3) and >10(5.0) were 11.5 +/- 5.5 and 21 +/- 6.0%, respectively. These rates increased to 20.5 +/- 6.4% and 25.0 +/- 3.0% when CTR serum titers were >10(5.0) CID50s/mL. Neither Aedes aegypti (L.) nor Aedes albopictus (Skuse) were infected by feeding on CTRs with titers of <10(5.0) CID50s/mL. The MEIRs of these two species were 11.5 +/- 3.5% and 1.5 +/- 0.5% after feeding on CTRs with titers of >10(5.0) CID50s/ml. None of the CTRs infected by mosquito bite or by needle showed any symptoms of WNV disease.