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Mars: new insights and unresolved questions – Corrigendum
- Hitesh G. Changela, Elias Chatzitheodoridis, Andre Antunes, David Beaty, Kristian Bouw, John C. Bridges, Klara Anna Capova, Charles S. Cockell, Catharine A. Conley, Ekaterina Dadachova, Tiffany D. Dallas, Stefaan de Mey, Chuanfei Dong, Alex Ellery, Martin Ferus, Bernard Foing, Xiaohui Fu, Kazuhisa Fujita, Yangting Lin, Sohan Jheeta, Leon J. Hicks, Sen Hu, Akos Kereszturi, Alexandros Krassakis, Yang Liu, Juergen Oberst, Joe Michalski, P. M. Ranjith, Teresa Rinaldi, David Rothery, Hector A. Stavrakakis, Laura Selbmann, Rishitosh K. Sinha, Alian Wang, Ken Williford, Zoltan Vaci, Jorge L. Vago, Michael Waltemathe, John E. Hallsworth
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- Journal:
- International Journal of Astrobiology / Volume 21 / Issue 1 / February 2022
- Published online by Cambridge University Press:
- 10 January 2022, p. 46
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Mars: new insights and unresolved questions
- Hitesh G. Changela, Elias Chatzitheodoridis, Andre Antunes, David Beaty, Kristian Bouw, John C. Bridges, Klara Anna Capova, Charles S. Cockell, Catharine A. Conley, Ekaterina Dadachova, Tiffany D. Dallas, Stefaan de Mey, Chuanfei Dong, Alex Ellery, Martin Ferus, Bernard Foing, Xiaohui Fu, Kazuhisa Fujita, Yangting Lin, Sohan Jheeta, Leon J. Hicks, Sen Hu, Akos Kereszturi, Alexandros Krassakis, Yang Liu, Juergen Oberst, Joe Michalski, P. M. Ranjith, Teresa Rinaldi, David Rothery, Hector A. Stavrakakis, Laura Selbmann, Rishitosh K. Sinha, Alian Wang, Ken Williford, Zoltan Vaci, Jorge L. Vago, Michael Waltemathe, John E. Hallsworth
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- International Journal of Astrobiology / Volume 20 / Issue 6 / December 2021
- Published online by Cambridge University Press:
- 01 December 2021, pp. 394-426
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Mars exploration motivates the search for extraterrestrial life, the development of space technologies, and the design of human missions and habitations. Here, we seek new insights and pose unresolved questions relating to the natural history of Mars, habitability, robotic and human exploration, planetary protection, and the impacts on human society. Key observations and findings include:
– high escape rates of early Mars' atmosphere, including loss of water, impact present-day habitability;
– putative fossils on Mars will likely be ambiguous biomarkers for life;
– microbial contamination resulting from human habitation is unavoidable; and
– based on Mars' current planetary protection category, robotic payload(s) should characterize the local martian environment for any life-forms prior to human habitation.
Some of the outstanding questions are:
– which interpretation of the hemispheric dichotomy of the planet is correct;
– to what degree did deep-penetrating faults transport subsurface liquids to Mars' surface;
– in what abundance are carbonates formed by atmospheric processes;
– what properties of martian meteorites could be used to constrain their source locations;
– the origin(s) of organic macromolecules;
– was/is Mars inhabited;
– how can missions designed to uncover microbial activity in the subsurface eliminate potential false positives caused by microbial contaminants from Earth;
– how can we ensure that humans and microbes form a stable and benign biosphere; and
– should humans relate to putative extraterrestrial life from a biocentric viewpoint (preservation of all biology), or anthropocentric viewpoint of expanding habitation of space?
Studies of Mars' evolution can shed light on the habitability of extrasolar planets. In addition, Mars exploration can drive future policy developments and confirm (or put into question) the feasibility and/or extent of human habitability of space.
Introduction: Critical Race Theory and the Health Sciences
- Khiara M. Bridges, Terence Keel, Osagie K. Obasogie
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- American Journal of Law & Medicine / Volume 43 / Issue 2-3 / May 2017
- Published online by Cambridge University Press:
- 06 January 2021, pp. 179-182
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- May 2017
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Shade and Plant Location Effects on Germination and Hormone Content of Palmer Amaranth (Amaranthus palmeri) Seed
- Prashant Jha, Jason K. Norsworthy, Melissa B. Riley, William Bridges, Jr.
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- Weed Science / Volume 58 / Issue 1 / March 2010
- Published online by Cambridge University Press:
- 20 January 2017, pp. 16-21
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Experiments were conducted to investigate the effects of shading on and location of the mother plant on germination and hormone content of Palmer amaranth seed. Increasing the shading from 0 to 87% decreased germination of fresh, viable seeds in dark from 25 to 12%. Abscisic acid (ABA) content of seeds from plants in 0% shade increased from 13.3 ng g−1 dry seed to 19.1 ng g−1 dry seed with 87% shade. Shading of the mother plant did not influence the 1,000-seed weight of Palmer amaranth. Seeds that matured in the top and middle third of the mother plant had 67 to 78% greater germination than those that matured in the bottom third of the mother plant. Endogenous gibberellic acid (GA) content of seeds did not differ between locations on the mother plant; however, the ABA content of seeds produced on the bottom third of the plant was 46 and 59% higher than the ABA content of seeds produced at the middle and top third of the plant, respectively. Endogenous ABA or GA content of seeds and 1,000-seed weight had no relationship with seed germination over and above the treatment effects. This research suggests that shading and plant location can influence germination of fresh, viable seeds of Palmer amaranth, which will be a dormancy strategy for seed dispersal over time.
Time of Emergence Affects Survival and Development of Wild Radish (Raphanus raphanistrum) in South Carolina
- Jason K. Norsworthy, Mayank S. Malik, Melissa B. Riley, William Bridges, Jr.
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- Weed Science / Volume 58 / Issue 4 / December 2010
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- 20 January 2017, pp. 402-407
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Field experiments were conducted from 2004 through 2006 at Pendleton and Clemson, SC, to determine the influence of seasonal emergence of wild radish on phenological development, survival, and seed and biomass production in a noncompetitive environment. The duration of four developmental phases, emergence to bolting, bolting to flowering, flowering to silique production, and silique production to maturity, were recorded following wild radish sowing at monthly intervals from October 2004 through September 2006. Seedling emergence occurred 2 to 4 wk after sowing. Mortality of seedlings that emerged from December through March was greater than that of seedlings that emerged in all other months. Wild radish that emerged from April through August completed its life cycle by summer or early autumn. Wild radish that emerged from September through November was able to survive the winter and complete its life cycle the following spring. The developmental phases most affected by time of emergence were emergence to bolting and bolting to flowering. The duration of emergence to bolting ranged from 249 to 479 growing degree days (GDD), and bolting to flowering from 270 to 373 GDD, depending on the month of emergence. The total life cycle of wild radish varied from a low of 1,267 GDD following June emergence to 1,503 GDD following November emergence. Multiple regression analysis revealed that emergence to bolting and silique production to maturity phases were dependent on accumulated heat units and photoperiod. Seed and biomass production were influenced by month of emergence. An average of 1,470 seeds plant−1 was produced when emergence occurred in July and 10,170 seeds plant−1 when emergence occurred in November. Plants that emerged in autumn exhibited minimal growth during the winter months, but conditions were conducive for growth in mid-March and April, with biomass production of 809 g plant−1 at silique production.
Influence of Glyphosate Timing and Row Width on Palmer Amaranth (Amaranthus palmeri) and Pusley (Richardia spp.) Demographics in Glyphosate-Resistant Soybean
- Prashant Jha, Jason K. Norsworthy, William Bridges, Jr., Melissa B. Riley
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- Journal:
- Weed Science / Volume 56 / Issue 3 / June 2008
- Published online by Cambridge University Press:
- 20 January 2017, pp. 408-415
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The influence of soybean row width and glyphosate application timing was determined on survival, biomass, and seed production of cohorts from a mixed population of Palmer amaranth and pusley species (Florida and Brazil pusley) along with soybean seed yield. The first Palmer amaranth and pusley cohort comprised plants that emerged from soybean planting through the V3 (3 wk after soybean emergence [WAE]) soybean stage (cohort 1). The second cohort comprised plants that emerged between the V3 to V6 (5 WAE) soybean stages (cohort 2), and the third cohort emerged after the V6 through the R2 soybean stage (cohort 3). Glyphosate at 840 g ae ha−1 was applied at V3; V6; V3 and V6; and V3, V6, and R2 in rows either 19 or 97 cm wide. A nontreated control was included for comparison in each row width. Sequential glyphosate applications at V3 and V6 or at V3, V6, and R2 soybean stages resulted in 1 to 3% survival of cohort 1 compared with 23 to 28% survival after a single glyphosate application. Vegetative biomass production by cohort 1 accounted for 71% of the total pusley biomass produced in the nontreated plots. Cohort 1, 2, and 3 contributed 68, 31, and 1%, respectively, of the total 37,900 seeds m−2 produced by pusley plants in nontreated plots. Delaying a glyphosate application to the V6 stage resulted in higher biomass and more than twice the seed produced from cohort 1 when compared with cohort 2. Glyphosate applied at V3 and V6 stages prevented pusley seed production from cohort 1, and an additional glyphosate application at the R2 stage prevented seed production from cohorts 2 and 3. No Palmer amaranth emergence occurred after the V6 soybean stage in either row width. A single glyphosate application at the V3 or V6 stage eliminated cohort 1 of Palmer amaranth in narrow rows. Palmer amaranth plants from cohort 1 in wide rows that survived the V3 glyphosate application produced 3.3 g m−2 biomass and 600 seeds m−2. Averaged over years and row widths, soybean yields after sequential glyphosate applications were 2,490 to 2,640 kg ha−1 compared with 1,850 to 2,020 kg ha−1 after a single glyphosate application at the V3 or V6 stage. This research confirms that sequential glyphosate applications are superior to a single application for minimizing pusley and Palmer amaranth survival, biomass, and seed production along with an improvement in soybean yields.
Use of Wild Radish (Raphanus raphanistrum) and Rye Cover Crops for Weed Suppression in Sweet Corn
- Mayank S. Malik, Jason K. Norsworthy, A. Stanley Culpepper, Melissa B. Riley, William Bridges, Jr.
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- Weed Science / Volume 56 / Issue 4 / August 2008
- Published online by Cambridge University Press:
- 20 January 2017, pp. 588-595
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Field experiments were conducted near Blackville, SC, and Tifton, GA, in 2004 and 2005, to evaluate the effect of wild radish and rye cover crops on weed control and sweet corn yield when used in conjunction with lower-than-recommended herbicide rates. Cover crop treatments included wild radish, rye, and no cover crop, alone and in conjunction with half and full rates of atrazine (0.84 and 1.68 kg ai ha−1) plus S-metolachlor (0.44 and 0.87 kg ai ha−1) applied before sweet corn emergence. Florida pusley, large crabgrass, spreading dayflower, ivyleaf morningglory, and wild radish infested the test sites. Wild radish and rye cover crops without herbicides reduced total weed density by 35 and 50%, respectively, at 4 wk after planting (WAP). Wild radish in conjunction with the full rate of atrazine plus S-metolachlor controlled Florida pusley, large crabgrass, and ivyleaf morningglory better than rye or no cover crop treated with a full herbicide rate in 2004 at Blackville. In 2005, at Blackville, weed control in sweet corn following wild radish cover crop plots alone was not different from that following rye. Wild radish or rye in conjunction with a half or full rate of atrazine and S-metolachlor controlled > 95% Florida pusley, wild radish, and large crabgrass in sweet corn at Tifton during both years. Ten glucosinolates, potential allelopathic compounds, were identified in wild radish, including glucoiberin, progoitrin, glucoraphanin, glucoraphenin, glucosinalbin, gluconapin, glucotropaeolin, glucoerucin, glucobrassicin, and gluconasturtin. Sweet corn yields at Blackville and Tifton following wild radish or rye cover crops were similar between the half and full rates of atrazine plus S-metolachlor. Sweet corn in wild radish or rye cover crop plots without herbicides produced less-marketable ears than herbicide-treated plots, indicating that a combination of cover crops and herbicides are required to optimize yields and to obtain desirable weed control.
Annual Changes in Temperature and Light Requirements for Germination of Palmer Amaranth (Amaranthus palmeri) Seeds Retrieved from Soil
- Prashant Jha, Jason K. Norsworthy, Melissa B. Riley, William Bridges, Jr.
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- Weed Science / Volume 58 / Issue 4 / December 2010
- Published online by Cambridge University Press:
- 20 January 2017, pp. 426-432
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Experiments were conducted on Palmer amaranth seeds collected in 2004 and 2006 from a natural population near Pendleton, SC, to determine the temperature and light requirements for germination of seeds retrieved from soil surface or from 10-cm depth in the field. A cyclic change in seed germination of Palmer amaranth in response to temperature and light occurred during a 12-mo after-ripening period. Freshly matured seeds collected in November required mean temperatures ≥ 25 C, and natural or red (R) light for increased germination. Following after-ripening in winter, seeds experienced a reduction in dormancy and germinated higher at 25 to 35 C mean compared with 10 to 15 C mean. With after-ripening for an additional 3 mo in May, seeds experienced a broadening of thermal range (10 to 40 C mean), and germination in natural light or R light was more than twice the germination in the absence of light. Fluctuating temperatures (7.5 C amplitude) improved germination over constant temperatures, except in summer and fall (9 and 12 mo after seed maturation). Exposure of seeds to high temperatures during summer caused secondary dormancy induction. Averaged over thermal amplitudes, seeds retrieved in fall required mean temperatures > 25 C for increased germination. Burial in spring for 3 to 6 mo induced seed dormancy, and the relative germination in fall (12 mo after seed maturation) was at least 50% higher for seeds retrieved from soil surface compared to seeds exhumed from 10-cm soil depth. Seeds retrieved in late summer and fall required natural light or R light for promoting germination, whereas far-red (FR) light or darkness inhibited germination. Furthermore, the effect of R and FR light was reversible, indicating a partially phytochrome-mediated germination response of Palmer amaranth seeds following 9 to 12 mo of after-ripening in the field.
Sicklepod (Senna obtusifolia) Survival and Fecundity in Wide- and Narrow-Row Glyphosate-Resistant Soybean
- Jason K. Norsworthy, Prashant Jha, William Bridges, Jr.
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- Weed Science / Volume 55 / Issue 3 / June 2007
- Published online by Cambridge University Press:
- 20 January 2017, pp. 252-259
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Experiments were conducted to determine the influence of soybean row width and glyphosate application timing on survival, biomass production, and fecundity of three sicklepod cohorts along with soybean seed yield. The first cohort comprised sicklepod plants that emerged from soybean planting through the V3 stage of soybean (two fully developed trifoliate leaves plus the unifoliate leaves; cohort 1). The second cohort comprised plants that emerged between the V3 to V6 stages of soybean (five fully developed trifoliate leaves plus the unifoliate leaves; cohort 2), and the third cohort emerged after the V6 stage through the R2 stage of soybean (full bloom; cohort 3). Glyphosate was applied at V3; V6; V3 and V6; and V3, V6, and R2 in rows 19 and 97 cm wide, and a nontreated control was included for comparison in each row width. Survival of cohort 1 in 2004 in glyphosate-treated plots occurred only after a single glyphosate application at V3 or V6 in wide rows. Narrowing the soybean row width reduced sicklepod survival throughout the growing season, even without glyphosate. Total biomass production from all cohorts averaged over years was 1,602 g m−2 in wide rows compared with 648 g m−2 in narrow rows. Cohort 1 accounted for 70 and 77% of the total sicklepod biomass in wide and narrow rows, respectively. Cohort 2 contributed 29% of the total sicklepod biomass in wide rows and 22% in narrow rows. Cohort 3 produced minimal biomass, contributing no more than 1% of the total sicklepod biomass. Sicklepod emerging after V6 failed to produce seed in 2004, and no sicklepod seed were produced in 2005 by plants emerging after V3. Averaged over years, sicklepod from cohort 1 in nontreated controls produced 3,695 seed m−2 in narrow rows compared with 6,685 seed m−2 in wide rows. Nontreated sicklepod from cohort 2 in 2004 produced 510 seed m−2 in narrow rows compared with 1,640 seed m−2 in wide rows. Soybean yields were similar among all glyphosate applications averaged over years and row widths, ranging from 3,340 to 3,700 kg ha−1 compared with 1,290 kg ha−1 without glyphosate (61 to 65% yield loss).
Temperature and Light Requirements for Wild Radish (Raphanus raphanistrum) Germination over a 12-Month Period following Maturation
- Mayank S. Malik, Jason K. Norsworthy, Melissa B. Riley, William Bridges, Jr.
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- Journal:
- Weed Science / Volume 58 / Issue 2 / June 2010
- Published online by Cambridge University Press:
- 20 January 2017, pp. 136-140
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Knowledge of the germination requirements of wild radish will help in determining the favorable conditions for germination and emergence and allow better management of this weed. Experiments were conducted during 2005 to 2006 and 2006 to 2007 to evaluate wild radish temperature and light requirements over a 12-mo period beginning in July on seeds placed on the soil surface and at a 10-cm depth. Germination response was influenced by temperature, light, duration of burial, and burial depth. Freshly harvested seeds (July) had no more than 18% germination whereas seeds allowed to after-ripen in the field for 3 to 6 mo (October to January) had up to 40% germination. The germination of wild radish retrieved from the soil surface was 1.2 to 1.5 times greater at alternating temperatures (2.5/17.5, 7.5/22.5, and 12.5/27.5 C) than at constant temperatures (10, 15, and 20 C) at 0, 3, and 6 mo after maturation. The light requirement for germination varied by time of year with no differences in germination between light and dark conditions for freshly harvested seeds. Far-red light inhibited germination of wild radish, indicating that wild radish may become sensitive to light following an after-ripening period.
Acclimation of Palmer Amaranth (Amaranthus palmeri) to Shading
- Prashant Jha, Jason K. Norsworthy, Melissa B. Riley, Douglas G. Bielenberg, William Bridges, Jr.
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- Journal:
- Weed Science / Volume 56 / Issue 5 / October 2008
- Published online by Cambridge University Press:
- 20 January 2017, pp. 729-734
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Experiments were conducted to investigate the acclimation of Palmer amaranth to shading. Plants were grown in the field beneath black shade cloths providing 47 and 87% shade and in full sunlight (no shading). All photosynthetic measurements were taken 4 wk after initiating the shade treatments. Photosynthetic rates of Palmer amaranth grown under 47% shade increased with increasing photosynthetic active radiation (PAR) similar to 0% shade-grown plants. Light-saturated photosynthetic rates were predicted beyond the highest measured PAR of 1,200 µmol m−2 s−1 for plants grown under 0 and 47% shade. Plants acclimated to increased shading by decreasing light-saturated photosynthetic rates from 60.5 µmol m−2 s−1 under full sun conditions to 26.4 µmol m−2 s−1 under 87% shade. Plants grown under 87% shade lowered their light compensation point. Rate of increase in plant height was similar among shade treatments. Plants responded to increased shading by a 13 to 44% reduction in leaf appearance rate (leaf number growing degree days [GDD]−1) and a 22 to 63% reduction in main-stem branch appearance rate (main-stem branch number GDD−1) compared with full sunlight. Palmer amaranth specific leaf area increased from 68 to 97 cm2 g−1 as shading increased to 87%. Plants acclimated to 47% shade by increasing total leaf chlorophyll from 22.8 µg cm−2 in full sunlight to 31.7 µg cm−2 when shaded; however, the increase was not significant at 87% shading. Thus, it is concluded that Palmer amaranth shows photosynthetic and morphological acclimation to 87% or less shading.
The Role of Soil and Landscape Factors in Chinese Privet (Ligustrum sinense) Invasion in the Appalachian Piedmont
- Donald L. Hagan, Elena A. Mikhailova, Timothy M. Shearman, Patrick T. Ma, Jedidah S. Nankaya, Samantha K. Hart, Hillary E. Valdetero, William C. Bridges, He Yun
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- Journal:
- Invasive Plant Science and Management / Volume 7 / Issue 3 / September 2014
- Published online by Cambridge University Press:
- 20 January 2017, pp. 483-490
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There is a limited understanding about the ecological mechanisms that enable certain plant species to become successful invaders of natural areas. This study was conducted to determine the soil and landscape characteristics that correlate with invasion of Chinese privet (CHP), and to develop a model to predict the probability of CHP invasion in Piedmont forests. A landscape ecosystem classification (LEC) system—based on the percentage of clay in the B horizon, depth to maximum clay (cm), exposure, terrain shape, and aspect (degrees)—was used to determine the soil moisture characteristics of invaded and uninvaded plots. Additional measurements included the cover classes of CHP and other species, litter depth (cm), slope (degrees), overstory basal area (m2 ha−1), and soil chemical properties. CHP invasion was negatively correlated with overstory basal area and slope and positively with litter depth and pH. A stepwise logistic regression model containing these four variables was highly sensitive, with an overall accuracy of 78%. Given the accuracy of this model, we propose that it can be used to calculate the probability of invasion in a given area, provided that some basic, readily obtainable site characteristics are known.
Aerodynamic characteristics of low-drag bicycle wheels
- D. I. Greenwell, N. J. Wood, E. K. L. Bridge, R. J. Addy
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- The Aeronautical Journal / Volume 99 / Issue 983 / March 1995
- Published online by Cambridge University Press:
- 04 July 2016, pp. 109-120
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A number of modern “aerodynamic” bicycle wheels were tested at full scale speeds in a windtunnel. The effects of wheel geometry, rotational speed and cross winds on drag force, side force and yawing moment were investigated.
Compared with a conventional spoked wheel, all the “aerodynamic” wheels were found to give similar improvements in drag of approximately 25%. In cross wind conditions, aerodynamic characteristics were strongly dependent on wheel geometry, but essentially independent of wheel rotational speed.
An experimental investigation of resonant interaction of a rectangular jet with a flat plate
- K. B. M. Q. Zaman, A. F. Fagan, J. E. Bridges, C. A. Brown
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- Journal:
- Journal of Fluid Mechanics / Volume 779 / 25 September 2015
- Published online by Cambridge University Press:
- 21 August 2015, pp. 751-775
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The interaction between an 8:1 aspect ratio rectangular jet and a flat plate, placed parallel to the jet, is addressed in this study. At high subsonic conditions and for certain relative locations of the plate, a resonance takes place with accompanying audible tones. Even when the tone is not audible the sound pressure level spectra are often marked by conspicuous peaks. The frequencies of these peaks, as functions of the plate’s length, its location relative to the jet as well as jet Mach number, are studied in an effort to understand the flow mechanism. It is demonstrated that the tones are not due to a simple feedback between the nozzle exit and the plate’s trailing edge; the leading edge also comes into play in determining the frequency. With parametric variation, it is found that there is an order in the most energetic spectral peaks; their frequencies cluster in distinct bands. The lowest frequency band is explained by an acoustic feedback involving diffraction at the plate’s leading edge. Under the resonant condition, a periodic flapping motion of the jet column is seen when viewed in a direction parallel to the plate. Phase-averaged Mach number data on a cross-stream plane near the plate’s trailing edge illustrate that the jet cross-section goes through large contortions within the period of the tone. Farther downstream a clear ‘axis switching’ takes place for the time-averaged cross-section of the jet that does not occur otherwise for a non-resonant condition.
Contributors
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- By Mitchell Aboulafia, Frederick Adams, Marilyn McCord Adams, Robert M. Adams, Laird Addis, James W. Allard, David Allison, William P. Alston, Karl Ameriks, C. Anthony Anderson, David Leech Anderson, Lanier Anderson, Roger Ariew, David Armstrong, Denis G. Arnold, E. J. Ashworth, Margaret Atherton, Robin Attfield, Bruce Aune, Edward Wilson Averill, Jody Azzouni, Kent Bach, Andrew Bailey, Lynne Rudder Baker, Thomas R. Baldwin, Jon Barwise, George Bealer, William Bechtel, Lawrence C. Becker, Mark A. Bedau, Ernst Behler, José A. Benardete, Ermanno Bencivenga, Jan Berg, Michael Bergmann, Robert L. Bernasconi, Sven Bernecker, Bernard Berofsky, Rod Bertolet, Charles J. Beyer, Christian Beyer, Joseph Bien, Joseph Bien, Peg Birmingham, Ivan Boh, James Bohman, Daniel Bonevac, Laurence BonJour, William J. Bouwsma, Raymond D. Bradley, Myles Brand, Richard B. Brandt, Michael E. Bratman, Stephen E. Braude, Daniel Breazeale, Angela Breitenbach, Jason Bridges, David O. Brink, Gordon G. Brittan, Justin Broackes, Dan W. Brock, Aaron Bronfman, Jeffrey E. Brower, Bartosz Brozek, Anthony Brueckner, Jeffrey Bub, Lara Buchak, Otavio Bueno, Ann E. Bumpus, Robert W. Burch, John Burgess, Arthur W. Burks, Panayot Butchvarov, Robert E. Butts, Marina Bykova, Patrick Byrne, David Carr, Noël Carroll, Edward S. Casey, Victor Caston, Victor Caston, Albert Casullo, Robert L. Causey, Alan K. L. Chan, Ruth Chang, Deen K. Chatterjee, Andrew Chignell, Roderick M. Chisholm, Kelly J. Clark, E. J. Coffman, Robin Collins, Brian P. Copenhaver, John Corcoran, John Cottingham, Roger Crisp, Frederick J. Crosson, Antonio S. Cua, Phillip D. Cummins, Martin Curd, Adam Cureton, Andrew Cutrofello, Stephen Darwall, Paul Sheldon Davies, Wayne A. Davis, Timothy Joseph Day, Claudio de Almeida, Mario De Caro, Mario De Caro, John Deigh, C. F. Delaney, Daniel C. Dennett, Michael R. DePaul, Michael Detlefsen, Daniel Trent Devereux, Philip E. Devine, John M. Dillon, Martin C. Dillon, Robert DiSalle, Mary Domski, Alan Donagan, Paul Draper, Fred Dretske, Mircea Dumitru, Wilhelm Dupré, Gerald Dworkin, John Earman, Ellery Eells, Catherine Z. Elgin, Berent Enç, Ronald P. Endicott, Edward Erwin, John Etchemendy, C. Stephen Evans, Susan L. Feagin, Solomon Feferman, Richard Feldman, Arthur Fine, Maurice A. Finocchiaro, William FitzPatrick, Richard E. Flathman, Gvozden Flego, Richard Foley, Graeme Forbes, Rainer Forst, Malcolm R. Forster, Daniel Fouke, Patrick Francken, Samuel Freeman, Elizabeth Fricker, Miranda Fricker, Michael Friedman, Michael Fuerstein, Richard A. Fumerton, Alan Gabbey, Pieranna Garavaso, Daniel Garber, Jorge L. A. Garcia, Robert K. Garcia, Don Garrett, Philip Gasper, Gerald Gaus, Berys Gaut, Bernard Gert, Roger F. Gibson, Cody Gilmore, Carl Ginet, Alan H. Goldman, Alvin I. Goldman, Alfonso Gömez-Lobo, Lenn E. Goodman, Robert M. Gordon, Stefan Gosepath, Jorge J. E. Gracia, Daniel W. Graham, George A. Graham, Peter J. Graham, Richard E. Grandy, I. Grattan-Guinness, John Greco, Philip T. Grier, Nicholas Griffin, Nicholas Griffin, David A. Griffiths, Paul J. Griffiths, Stephen R. Grimm, Charles L. Griswold, Charles B. Guignon, Pete A. Y. Gunter, Dimitri Gutas, Gary Gutting, Paul Guyer, Kwame Gyekye, Oscar A. Haac, Raul Hakli, Raul Hakli, Michael Hallett, Edward C. Halper, Jean Hampton, R. James Hankinson, K. R. Hanley, Russell Hardin, Robert M. Harnish, William Harper, David Harrah, Kevin Hart, Ali Hasan, William Hasker, John Haugeland, Roger Hausheer, William Heald, Peter Heath, Richard Heck, John F. Heil, Vincent F. Hendricks, Stephen Hetherington, Francis Heylighen, Kathleen Marie Higgins, Risto Hilpinen, Harold T. Hodes, Joshua Hoffman, Alan Holland, Robert L. Holmes, Richard Holton, Brad W. Hooker, Terence E. Horgan, Tamara Horowitz, Paul Horwich, Vittorio Hösle, Paul Hoβfeld, Daniel Howard-Snyder, Frances Howard-Snyder, Anne Hudson, Deal W. Hudson, Carl A. Huffman, David L. Hull, Patricia Huntington, Thomas Hurka, Paul Hurley, Rosalind Hursthouse, Guillermo Hurtado, Ronald E. Hustwit, Sarah Hutton, Jonathan Jenkins Ichikawa, Harry A. Ide, David Ingram, Philip J. Ivanhoe, Alfred L. Ivry, Frank Jackson, Dale Jacquette, Joseph Jedwab, Richard Jeffrey, David Alan Johnson, Edward Johnson, Mark D. Jordan, Richard Joyce, Hwa Yol Jung, Robert Hillary Kane, Tomis Kapitan, Jacquelyn Ann K. Kegley, James A. Keller, Ralph Kennedy, Sergei Khoruzhii, Jaegwon Kim, Yersu Kim, Nathan L. King, Patricia Kitcher, Peter D. Klein, E. D. Klemke, Virginia Klenk, George L. Kline, Christian Klotz, Simo Knuuttila, Joseph J. Kockelmans, Konstantin Kolenda, Sebastian Tomasz Kołodziejczyk, Isaac Kramnick, Richard Kraut, Fred Kroon, Manfred Kuehn, Steven T. Kuhn, Henry E. Kyburg, John Lachs, Jennifer Lackey, Stephen E. Lahey, Andrea Lavazza, Thomas H. Leahey, Joo Heung Lee, Keith Lehrer, Dorothy Leland, Noah M. Lemos, Ernest LePore, Sarah-Jane Leslie, Isaac Levi, Andrew Levine, Alan E. Lewis, Daniel E. Little, Shu-hsien Liu, Shu-hsien Liu, Alan K. L. Chan, Brian Loar, Lawrence B. Lombard, John Longeway, Dominic McIver Lopes, Michael J. Loux, E. J. Lowe, Steven Luper, Eugene C. Luschei, William G. Lycan, David Lyons, David Macarthur, Danielle Macbeth, Scott MacDonald, Jacob L. Mackey, Louis H. Mackey, Penelope Mackie, Edward H. Madden, Penelope Maddy, G. B. Madison, Bernd Magnus, Pekka Mäkelä, Rudolf A. Makkreel, David Manley, William E. Mann (W.E.M.), Vladimir Marchenkov, Peter Markie, Jean-Pierre Marquis, Ausonio Marras, Mike W. Martin, A. P. Martinich, William L. McBride, David McCabe, Storrs McCall, Hugh J. McCann, Robert N. McCauley, John J. McDermott, Sarah McGrath, Ralph McInerny, Daniel J. McKaughan, Thomas McKay, Michael McKinsey, Brian P. McLaughlin, Ernan McMullin, Anthonie Meijers, Jack W. Meiland, William Jason Melanson, Alfred R. Mele, Joseph R. Mendola, Christopher Menzel, Michael J. Meyer, Christian B. Miller, David W. Miller, Peter Millican, Robert N. Minor, Phillip Mitsis, James A. Montmarquet, Michael S. Moore, Tim Moore, Benjamin Morison, Donald R. Morrison, Stephen J. Morse, Paul K. Moser, Alexander P. D. Mourelatos, Ian Mueller, James Bernard Murphy, Mark C. Murphy, Steven Nadler, Jan Narveson, Alan Nelson, Jerome Neu, Samuel Newlands, Kai Nielsen, Ilkka Niiniluoto, Carlos G. Noreña, Calvin G. Normore, David Fate Norton, Nikolaj Nottelmann, Donald Nute, David S. Oderberg, Steve Odin, Michael O’Rourke, Willard G. Oxtoby, Heinz Paetzold, George S. Pappas, Anthony J. Parel, Lydia Patton, R. P. Peerenboom, Francis Jeffry Pelletier, Adriaan T. Peperzak, Derk Pereboom, Jaroslav Peregrin, Glen Pettigrove, Philip Pettit, Edmund L. Pincoffs, Andrew Pinsent, Robert B. Pippin, Alvin Plantinga, Louis P. Pojman, Richard H. Popkin, John F. Post, Carl J. Posy, William J. Prior, Richard Purtill, Michael Quante, Philip L. Quinn, Philip L. Quinn, Elizabeth S. Radcliffe, Diana Raffman, Gerard Raulet, Stephen L. Read, Andrews Reath, Andrew Reisner, Nicholas Rescher, Henry S. Richardson, Robert C. Richardson, Thomas Ricketts, Wayne D. Riggs, Mark Roberts, Robert C. Roberts, Luke Robinson, Alexander Rosenberg, Gary Rosenkranz, Bernice Glatzer Rosenthal, Adina L. Roskies, William L. Rowe, T. M. Rudavsky, Michael Ruse, Bruce Russell, Lilly-Marlene Russow, Dan Ryder, R. M. Sainsbury, Joseph Salerno, Nathan Salmon, Wesley C. Salmon, Constantine Sandis, David H. Sanford, Marco Santambrogio, David Sapire, Ruth A. Saunders, Geoffrey Sayre-McCord, Charles Sayward, James P. Scanlan, Richard Schacht, Tamar Schapiro, Frederick F. Schmitt, Jerome B. Schneewind, Calvin O. Schrag, Alan D. Schrift, George F. Schumm, Jean-Loup Seban, David N. Sedley, Kenneth Seeskin, Krister Segerberg, Charlene Haddock Seigfried, Dennis M. Senchuk, James F. Sennett, William Lad Sessions, Stewart Shapiro, Tommie Shelby, Donald W. Sherburne, Christopher Shields, Roger A. Shiner, Sydney Shoemaker, Robert K. Shope, Kwong-loi Shun, Wilfried Sieg, A. John Simmons, Robert L. Simon, Marcus G. Singer, Georgette Sinkler, Walter Sinnott-Armstrong, Matti T. Sintonen, Lawrence Sklar, Brian Skyrms, Robert C. Sleigh, Michael Anthony Slote, Hans Sluga, Barry Smith, Michael Smith, Robin Smith, Robert Sokolowski, Robert C. Solomon, Marta Soniewicka, Philip Soper, Ernest Sosa, Nicholas Southwood, Paul Vincent Spade, T. L. S. Sprigge, Eric O. Springsted, George J. Stack, Rebecca Stangl, Jason Stanley, Florian Steinberger, Sören Stenlund, Christopher Stephens, James P. Sterba, Josef Stern, Matthias Steup, M. A. Stewart, Leopold Stubenberg, Edith Dudley Sulla, Frederick Suppe, Jere Paul Surber, David George Sussman, Sigrún Svavarsdóttir, Zeno G. Swijtink, Richard Swinburne, Charles C. Taliaferro, Robert B. Talisse, John Tasioulas, Paul Teller, Larry S. Temkin, Mark Textor, H. S. Thayer, Peter Thielke, Alan Thomas, Amie L. 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- Edited by Robert Audi, University of Notre Dame, Indiana
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- The Cambridge Dictionary of Philosophy
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- 05 August 2015
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- 27 April 2015, pp ix-xxx
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- By Dor Abrahamson, Jerry Andriessen, Roger Azevedo, Michael Baker, Ryan Baker, Sasha Barab, Carl Bereiter, Susan Bridges, Mario Carretero, Carol K. K. Chan, Clark A. Chinn, Paul Cobb, Allan Collins, Kevin Crowley, Elizabeth A. Davis, Chris Dede, Sharon J. Derry, Andrea A. diSessa, Michael Eisenberg, Yrjö Engeström, Noel Enyedy, Barry J. Fishman, Ricki Goldman, James G. Greeno, Erica Rosenfeld Halverson, Cindy E. Hmelo-Silver, Michael J. Jacobson, Sanna Järvelä, Yasmin B. Kafai, Yael Kali, Manu Kapur, Paul A. Kirschner, Karen Knutson, Timothy Koschmann, Joseph S. Krajcik, Carol D. Lee, Peter Lee, Robb Lindgren, Jingyan Lu, Richard E. Mayer, Naomi Miyake, Na’ilah Suad Nasir, Mitchell J. Nathan, Narcis Pares, Roy Pea, James W. Pellegrino, William R. Penuel, Palmyre Pierroux, Brian J. Reiser, K. Ann Renninger, Ann S. Rosebery, R. Keith Sawyer, Marlene Scardamalia, Anna Sfard, Mike Sharples, Kimberly M. Sheridan, Bruce L. Sherin, Namsoo Shin, George Siemens, Peter Smagorinsky, Nancy Butler Songer, James P. Spillane, Kurt Squire, Gerry Stahl, Constance Steinkuehler, Reed Stevens, Daniel Suthers, Iris Tabak, Beth Warren, Uri Wilensky, Philip H. Winne, Carmen Zahn
- Edited by R. Keith Sawyer, University of North Carolina, Chapel Hill
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- The Cambridge Handbook of the Learning Sciences
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- 05 November 2014
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- 17 November 2014, pp xv-xviii
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- By Michael H. Allen, Leora Amira, Victoria Arango, David W. Ayer, Helene Bach, Christopher R. Bailey, Ross J. Baldessarini, Kelsey Ball, Alan L. Berman, Marian E. Betz, Emily A. Biggs, R. Warwick Blood, Kathleen T. Brady, David A. Brent, Jeffrey A. Bridge, Gregory K. Brown, Anat Brunstein Klomek, A. Jacqueline Buchanan, Michelle J. Chandley, Tim Coffey, Jessica Coker, Yeates Conwell, Scott J. Crow, Collin L. Davidson, Yogesh Dwivedi, Stacey Espaillat, Jan Fawcett, Steven J. Garlow, Robert D. Gibbons, Catherine R. Glenn, Deborah Goebert, Erica Goldstein, Tina R. Goldstein, Madelyn S. Gould, Kelly L. Green, Alison M. Greene, Philip D. Harvey, Robert M. A. Hirschfeld, Donna Holland Barnes, Andres M. Kanner, Gary J. Kennedy, Stephen H. Koslow, Benoit Labonté, Alison M. Lake, William B. Lawson, Steve Leifman, Adam Lesser, Timothy W. Lineberry, Amanda L. McMillan, Herbert Y. Meltzer, Michael Craig Miller, Michael J. Miller, James A. Naifeh, Katharine J. Nelson, Charles B. Nemeroff, Alexander Neumeister, Matthew K. Nock, Jennifer H. Olson-Madden, Gregory A. Ordway, Michael W. Otto, Ghanshyam N. Pandey, Giampaolo Perna, Jane Pirkis, Kelly Posner, Anne Rohs, Pedro Ruiz, Molly Ryan, Alan F. Schatzberg, S. Charles Schulz, M. Katherine Shear, Morton M. Silverman, April R. Smith, Marcus Sokolowski, Barbara Stanley, Zachary N. Stowe, Sarah A. Struthers, Leonardo Tondo, Gustavo Turecki, Robert J. Ursano, Kimberly Van Orden, Anne C. Ward, Danuta Wasserman, Jerzy Wasserman, Melinda K. Westlund, Tracy K. Witte, Kseniya Yershova, Alexandra Zagoloff, Sidney Zisook
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- A Concise Guide to Understanding Suicide
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- 05 October 2014
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- 18 September 2014, pp vii-x
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- By Tom Abbott, Gareth L. Ackland, Hollman D. Aya, Berthold Bein, Karim Bendjelid, Matthieu Biais, Elizabeth J. Bridges, Maxime Cannesson, Cédric Carrié, Alice Carter, Maurizio Cecconi, Daniel Chappell, Jason H. Chua, Gary Colins, Diego Orbegozo Cortes, Lester A. H. Critchley, Daniel De Backer, Katia Donadello, Eric Edison, Byron D. Fergerson, Tong J. Gan, Michael T. Ganter, Leslie M. Garson, Christoph K. Hofer, Christoph Ilies, James M. Isbell, Matthias Jacob, Mazyar Javidroozi, Zeev N. Kain, Elisa Kam, Gautam Kumar, Yannick Le Manach, Sheldon Magder, Aman Mahajan, Gerard R. Manecke, Paul E. Marik, Joseph Meltzer, Debra R. Metter, Timothy E. Miller, Xavier Monnet, Michael Mythen, Rudolph Nguyen, Rupert Pearse, Michael R. Pinsky, Davinder Ramsingh, Steffen Rex, Andrew Rhodes, Joseph Rinehart, Mathieu Sèrié, Aryeh Shander, Nils Siegenthaler, Ann B. Singleton, Faraz Syed, Jean-Louis Teboul, Robert H. Thiele, Shermeen B. Vakharia, Trung Vu, Nathan H. Waldron, David Walker, William Wilson
- Edited by Maxime Cannesson, University of California, Irvine, Rupert Pearse
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- Perioperative Hemodynamic Monitoring and Goal Directed Therapy
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- 05 September 2014
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- 04 September 2014, pp vii-x
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Coordinated Microanalyses of Seven Particles of Probable Interstellar Origin from the Stardust Mission.
- Andrew J. Westphal, Rhonda M. Stroud, Hans A. Bechtel, Frank E. Brenker, Anna L. Butterworth, George J. Flynn, David R. Frank, Zack Gainsforth, Jon K. Hillier, Frank Postberg, Alexandre S. Simionovici, Veerle J. Sterken, Carlton Allen, David Anderson, Asna Ansari, Saˇsa Bajt, Ron K. Bastien, Nabil Bassim, John Bridges, Donald E. Brownlee, Mark Burchell, Manfred Burghammer, Hitesh Changela, Peter Cloetens, Andrew M. Davis, Ryan Doll, Christine Floss, Eberhard Gru¨n, Philipp R. Heck, Peter Hoppe, Bruce Hudson, Joachim Huth, Anton Kearsley, Ashley J. King, Barry Lai, Jan Leitner, Laurence Lemelle, Ariel Leonard, Hugues Leroux, Robert Lettieri, William Marchant, Larry R. Nittler, Ryan Ogliore, Wei Jia Ong, Mark C. Price, Scott A. Sandford, Juan-Angel Sans Tresseras, Sylvia Schmitz, Tom Schoonjans, Kate Schreiber, Geert Silversmit, Vicente A. Solé, Ralf Srama, Frank Stadermann, Thomas Stephan, Julien Stodolna, Stephen Sutton, Mario Trieloff, Peter Tsou, Tolek Tyliszczak, Bart Vekemans, Laszlo Vincze, Joshua Von Korff, Naomi Wordsworth, Daniel Zevin, Michael E. Zolensky
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- Journal:
- Microscopy and Microanalysis / Volume 20 / Issue S3 / August 2014
- Published online by Cambridge University Press:
- 27 August 2014, pp. 1692-1693
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- August 2014
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Enhanced visible-light absorption of mesoporous TiO2 by co-doping with transition-metal/nitrogen ions
- J. E. Mathis, Z. Bi, C. A. Bridges, M. K. Kidder, M. P. Paranthaman
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- Journal:
- MRS Online Proceedings Library Archive / Volume 1547 / 2013
- Published online by Cambridge University Press:
- 21 May 2013, pp. 115-119
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- 2013
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Titanium (IV) oxide, TiO2, has been the object of intense scrutiny for energy applications. TiO2 is inexpensive, non-toxic, and has excellent corrosion resistance when exposed to electrolytes. A major drawback preventing the widespread use TiO2 for photolysis is its relatively large band gap of ∼3eV. Only light with wavelengths shorter than 400 nm, which is in the ultraviolet portion of the spectrum, has sufficient energy to be absorbed. Less than 14 percent of the solar irradiation reaching the earth’s surface has energy exceeding this band gap. Adding dopants such as transition metals has long been used to reduce the gap and increase photocatalytic activity by accessing the visible part of the solar spectrum. The degree to which the band gap is reduced using transition metals depends in part on the overlap of the d-orbitals of the transition metals with the oxygen p-orbitals. Therefore, doping with anions such as nitrogen to modify the cation-anion orbital overlap is another approach to reduce the gap. Recent studies suggest that using a combination of transition metals and nitrogen as dopants is more effective at introducing intermediate states within the band gap, effectively narrowing it. Here we report the synthesis of mesoporous TiO2 spheres, co-doped with transition metals and nitrogen that exhibit a nearly flat absorbance response across the visible spectrum extending into the near infrared.