Journal articles on the topic 'Marginal quality'

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1

Tanji, K. K. "Irrigation with Marginal Quality Waters: Issues." Journal of Irrigation and Drainage Engineering 123, no. 3 (May 1997): 165–69. http://dx.doi.org/10.1061/(asce)0733-9437(1997)123:3(165).

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Wolf, David, H. Allen Klaiber, and Sathya Gopalakrishnan. "Beyond marginal: Estimating the demand for water quality." Resource and Energy Economics 68 (May 2022): 101299. http://dx.doi.org/10.1016/j.reseneeco.2022.101299.

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3

Mirza, D. F., B. K. Gunson, RenatoF Da Silva, A. D. Mayer, J. A. C. Buckels, and P. McMaster. "Policies in Europe on "marginal quality" donor livers." Lancet 344, no. 8935 (November 1994): 1480–83. http://dx.doi.org/10.1016/s0140-6736(94)90294-1.

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4

Benetti, Ana R., Anne Peutzfeldt, Adrian Lussi, and Simon Flury. "Resin composites: Modulus of elasticity and marginal quality." Journal of Dentistry 42, no. 9 (September 2014): 1185–92. http://dx.doi.org/10.1016/j.jdent.2014.07.004.

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5

SCHMITT, PAMELA M. "A VERTICALLY DIFFERENTIATED DUOPOLY WITH MARGINAL COST DIFFERENTIALS." International Game Theory Review 05, no. 01 (March 2003): 73–81. http://dx.doi.org/10.1142/s0219198903000908.

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A vertically differentiated duopoly model analyzes the impact of marginal cost differentials on price and quality. Firms play a two-stage game, first simultaneously choosing quality and then simultaneously choosing price. When the firm producing the high quality good faces an increase in its marginal cost, both firms increase price and upgrade quality. When the firm producing the low quality good faces an increase in its marginal cost, both firms decrease price and downgrade quality. When a first firm enters the market, quality position decisions are examined under the assumption that both the firm-specific and the quality-specific marginal costs are higher when a firm produces a higher quality good. The results show that the first entrant produces the low quality good and earns higher profits.
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6

Rabbani, Emilia Kohlman, and Graham Bullen. "Marginal Delay: New Measure for Quality of Service at Signalized Intersections." Transportation Research Record: Journal of the Transportation Research Board 1802, no. 1 (January 2002): 32–43. http://dx.doi.org/10.3141/1802-05.

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Most existing analytical models determine signal settings at intersections by minimizing total delay. The main problem with these methods is that when green split is based on minimum total intersection delay, low-volume approaches are penalized. Although this may be appropriate, the extent of this penalty has never been theoretically resolved. A new concept and its methodology for determining traffic signal settings were proposed to provide a theoretical basis for this issue. This new concept, marginal delay, has its inception in marginal analysis and is defined as the increase in total delay resulting from a one-vehicle increase in the approach volume. Given the nature of the existing delay equations, marginal delay also represents the measure of the maximum individual vehicle delay for a given cycle. Three marginal delay equations were derived and analyzed over a range of 265 cases. Marginal delay analysis was applied to signal-setting calculations and compared with existing delay models. The work concluded that marginal delay is a significant variable in the calculation of signal settings, especially when large differences exist between the volumes of the different approaches. Furthermore, marginal delay used in conjunction with total delay can improve current signal-timing methods by quantifying the penalty applied to light-volume approaches and by providing a measure of variance between real-time flow and design flow.
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Hayashi, M., N. H. F. Wilson, and D. C. Watts. "Quality of Marginal Adaptation Evaluation of Posterior Composites in Clinical Trials." Journal of Dental Research 82, no. 1 (January 2003): 59–63. http://dx.doi.org/10.1177/154405910308200113.

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The evaluation of margins of restorations in clinical trials relies on the subjective assessment of evaluators, with no instrument having been developed, let alone validated, to assist in the process. The purpose of the present study was to assess the quality of evaluations of marginal adaptation by analyzing the distribution of marginal steps rated according to clinical criteria. Replicas of 435 restorations, the marginal qualities of which had been evaluated according to modified USPHS criteria, were randomly selected from the Occlusin TM multi-center clinical trial program. The marginal step height in the most deteriorated area of each restoration was measured by means of a digital step-height instrument. An overlap between the steps in the restorations with A (Alfa; replacement unnecessary) and B (Bravo; replacement questionable) ratings was found to be in the range of 101 μm to 321 μm. When the steps with a height greater or less than one standard deviation of the mean were excluded, the overlap was reduced to a range of 168 μm to 173 μm. This finding indicates a marginal height boundary between A and B ratings for marginal adaptation of 170 ± 3 μm.
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8

Steller, Marcel, and Erich Pummerer. "Auditor’s Income Taxation and Audit Quality." SAGE Open 11, no. 3 (July 2021): 215824402110408. http://dx.doi.org/10.1177/21582440211040833.

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We use an analytical research model to analyze the effect of the auditor’s personal income tax on audit effort. We show that the auditor’s level of care crucially depends on the tax rate and amount of loss recognition. Taxes may cause paradoxical effects on the auditor’s effort, audit quality, and marginal audit fee if profits and losses are taxed differently or in case of risk-averse decision-makers. Therefore, compared with the pretax setting, taxes have distortional effects. Thus, common auditing standards (e.g., International Standards on Auditing framework) will imply diverse audit quality and marginal audit fees depending on the respective national tax law. Our results are relevant for standard setters, auditors, and financial statements’ addressees.
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9

Grobler, Carla, Philip J. Wolfe, Kingshuk Dasadhikari, Irene C. Dedoussi, Florian Allroggen, Raymond L. Speth, Sebastian D. Eastham, et al. "Marginal climate and air quality costs of aviation emissions." Environmental Research Letters 14, no. 11 (November 8, 2019): 114031. http://dx.doi.org/10.1088/1748-9326/ab4942.

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10

Woods, P. W., V. A. Marker, T. W. McKinney, B. H. Miller, and T. Okabe. "Determining Amalgam Marginal Quality: Effect of Occlusal Surface Condition." Journal of the American Dental Association 124, no. 5 (May 1993): 60–65. http://dx.doi.org/10.14219/jada.archive.1993.0108.

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11

GROSSMAN, E. S., and J. M. MATEJKA. "Amalgam marginal quality assessment: a comparison of seven methods." Journal of Oral Rehabilitation 24, no. 7 (July 1997): 496–505. http://dx.doi.org/10.1046/j.1365-2842.1997.00529.x.

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12

Jordan, Jeffery L., R. L. Shewfelt, S. E. Prussia, and W. C. Hurst. "Estimating Implicit Marginal Prices of Quality Characteristics of Tomatoes." Journal of Agricultural and Applied Economics 17, no. 2 (December 1985): 139–46. http://dx.doi.org/10.1017/s0081305200025139.

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AbstractA hedonic price function is developed for estimating the implicit prices for selected quality characteristics of fresh tomatoes at three points in the marketing season. The estimation of this function, proposed as a method of evaluating changes in the post-harvest system, is accomplished using a flexible functional form. Those quality characteristics that most affect the price of tomatoes can help determine the economic feasibility of alternative handling techniques or new technologies.
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Manhart, Juergen, Hong Yan Chen, Albert Mehl, Karin Weber, and Reinhard Hickel. "Marginal quality and microleakage of adhesive class V restorations." Journal of Dentistry 29, no. 2 (February 2001): 123–30. http://dx.doi.org/10.1016/s0300-5712(00)00066-x.

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14

Gorodovsky, Sergio, and Omar Zidan. "Retentive strength, disintegration, and marginal quality of luting cements." Journal of Prosthetic Dentistry 68, no. 2 (August 1992): 269–74. http://dx.doi.org/10.1016/0022-3913(92)90328-8.

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15

De Pasquale, C., M. L. Pistorio, P. Veroux, G. Giuffrida, N. Sinagra, B. Ekser, D. Zerbo, D. Corona, A. Giaquinta, and M. Veroux. "Quality of Life in Kidney Transplantation From Marginal Donors." Transplantation Proceedings 43, no. 4 (May 2011): 1045–47. http://dx.doi.org/10.1016/j.transproceed.2011.01.156.

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GROSSMAN, E. S., and J. M. MATEJKA. "Amalgam marginal quality assessment: a comparison of seven methods." Journal of Oral Rehabilitation 24, no. 7 (June 28, 2008): 496–505. http://dx.doi.org/10.1111/j.1365-2842.1997.tb00364.x.

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17

Schmidlin, P. R., K. Wolleb, T. Imfeld, M. Gygax, and A. Lussi. "Influence of Beveling and Ultrasound Application on Marginal Adaptation of Box-only Class II (slot) Resin Composite Restorations." Operative Dentistry 32, no. 3 (May 1, 2007): 291–97. http://dx.doi.org/10.2341/06-84.

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Clinical Relevance Beveling box-only Class II cavities is necessary to improve the marginal quality of restorations. Where beveling is impossible or difficult to achieve, ultrasound may improve marginal quality.
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18

Gerwin, Werner, Frank Repmann, Spyridon Galatsidas, Despoina Vlachaki, Nikos Gounaris, Wibke Baumgarten, Christiane Volkmann, Dimitrios Keramitzis, Fotis Kiourtsis, and Dirk Freese. "Assessment and quantification of marginal lands for biomass production in Europe using soil-quality indicators." SOIL 4, no. 4 (December 6, 2018): 267–90. http://dx.doi.org/10.5194/soil-4-267-2018.

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Abstract. The cultivation of bioenergy plants in fertile, arable lands increasingly results in new land use conflicts with food production and cannot be considered as sustainable. Marginal lands have been frequently considered as potential alternatives for producing bioenergy from biomass. However, clear definitions and assessment methods for selecting marginal lands and for calculating potentials are still widely missing. The project “SEEMLA” aims at triggering the exploitation of currently underused marginal lands for biomass production for energy purposes. Study sites have been selected in different European countries: Germany, Greece, and Ukraine. The selected sites represent a wide variety of different types of marginal lands. Based on a soil assessment set given by the Muencheberg Soil Quality Rating (SQR) system potentially “marginal” sites have been investigated. The SQR system allows for clearly distinguishing between soils of higher and lower quality. Soils with SQR scores below 40 are regarded as “marginal”. They can be classified into different groups with regard to the importance of soil hazard indicators as evaluated by the SQR approach. The calculated SQR scores correlate significantly with biomass yields of bioenergy plants. Further, the SQR method was adapted for use in a GIS study on marginal-land potentials in Europe. Thus, 46 % of the investigated European area could be classified as “marginal” with SQR scores below 40. From that area 22.6 % can be considered as potentially suitable for producing renewable resources after eliminating protected sites or other places not suitable for any kind of land use. Taking the ecological demands of selected bioenergy plants into account it is possible to give first preliminary recommendations for regional crop cultivation. It can be concluded that Europe offers a large potential for renewable resources from marginal sites. However, the implementation into practice is often impeded by missing or varying policies and regulations. A proper implementation needs clear regulations and also incentives for farmers at the European level.
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19

Naumova, Ella A., Fabian Schiml, Wolfgang H. Arnold, and Andree Piwowarczyk. "Marginal quality of ceramic inlays after three different instrumental cavity preparation methods of the proximal boxes." Clinical Oral Investigations 23, no. 2 (June 4, 2018): 793–803. http://dx.doi.org/10.1007/s00784-018-2492-0.

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Abstract Objectives The marginal quality of ceramic inlays was evaluated after the use of three different instrumental finishing methods in mesio-occluso-distal (mod) cavity boxes in vitro after hydrothermal loading (HTL). Materials and methods Caries-free human molars were divided into three groups. Mod-cavities were conventionally prepared. Box finishing was performed in every group with rotating (RI), sonic (SI), or ultrasonic (USI) instruments. Surface roughness was examined. Twelve mod-cavities remained untreated. Continuous margin quality was evaluated with scanning electron microscopy (SEM). Ceramic inlays were cemented into cavities. After HTL microleakage, marginal and absolute marginal gaps were examined. All data were analyzed statistically. Results Significant differences were found, between cavity surface roughness of RI and SI groups, the RI and USI groups, but not between microleakage, marginal, absolute marginal gaps after HTL and in proximal marginal quality. No correlations between microleakage and marginal gaps nor between microleakage and surface roughness were found. Conclusion Mod-cavity proximal box finishing with SI or USI resulted in a higher surface roughness than the use of RI. The type of the finishing method did not influence the marginal quality of ceramic inlays. For the mod-cavity finishing, the use of SI and USI could be an alternative instrumental method to conventional RI methods with a lower risk of iatrogenic damage of the adjacent teeth. Clinical relevance This study allows the practitioner to better determine the proper indications and limitations of the sonic and ultrasonic instruments for mod-cavity proximal box finishing.
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20

Jia, Liyan, Jinsub Kim, Robert J. Thomas, and Lang Tong. "Impact of Data Quality on Real-Time Locational Marginal Price." IEEE Transactions on Power Systems 29, no. 2 (March 2014): 627–36. http://dx.doi.org/10.1109/tpwrs.2013.2286992.

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21

Boland, Michael, and Ted Schroeder. "Marginal Value of Quality Attributes for Natural and Organic Beef." Journal of Agricultural and Applied Economics 34, no. 1 (April 2002): 39–49. http://dx.doi.org/10.1017/s1074070800002133.

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AbstractThe objective of this research is to determine the marginal value of attributes to consumers with respect to natural beef or beef produced with organic grains. A hedonic model is used to value attributes of 11 different primal cuts. Results suggest that producers under this particular natural/implant-free marketing alliance should market high-yielding animals rather than high-quality grading animals. Consumers of this beef value taste, as measured by dry aging, and leanness, as measured by USDA Select grade. The economic magnitudes of the variables under a producer's control were small relative to those that could be controlled by a processor.
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22

Shalhevet, Joseph. "Using water of marginal quality for crop production: major issues." Agricultural Water Management 25, no. 3 (July 1994): 233–69. http://dx.doi.org/10.1016/0378-3774(94)90063-9.

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23

Marchesi, G., A. Frassetto, G. Turco, L. Breschi, and M. Cadenaro. "Marginal quality of direct composite veneering system for cervical fillings." Dental Materials 31 (2015): e43. http://dx.doi.org/10.1016/j.dental.2015.08.096.

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24

Biswas, Asit K., and Abdullah Arar. "Use of marginal quality water for plant production in Europe." International Journal of Water Resources Development 4, no. 2 (June 1988): 127–41. http://dx.doi.org/10.1080/07900628808722382.

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25

Sun, Jiajun. "Marginal quality-based long-term incentive mechanisms for crowd sensing." International Journal of Communication Systems 29, no. 5 (June 16, 2015): 942–58. http://dx.doi.org/10.1002/dac.3001.

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26

Lutz, F., I. Krejci, and F. Barbakow. "Quality and durability of marginal adaptation in bonded composite restorations." Dental Materials 7, no. 2 (April 1991): 107–13. http://dx.doi.org/10.1016/0109-5641(91)90055-4.

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27

Schubert, Oliver, Kurt-Jürgen Erdelt, Roland Tittenhofer, Jan Hajtó, Alexander Bergmann, and Jan-Frederik Güth. "Influence of intraoral scanning on the quality of preparations for all-ceramic single crowns." Clinical Oral Investigations 24, no. 12 (May 20, 2020): 4511–18. http://dx.doi.org/10.1007/s00784-020-03316-2.

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Abstract Objectives To evaluate the influence of intraoral scanning on the quality of preparations for all-ceramic single crowns. Material and methods A total of 690 randomly selected and anonymized in vivo single crown preparations were examined. Three hundred twenty-three preparations were directly recorded with an intraoral scanner (group IS). Data from plaster casts digitized by a laboratory scanner (group ID; N = 367) served as control. Comparisons included convergence angle, marginal design, marginal substance reduction, homogeneity of the finish line, and undercuts. Evaluation was performed using fully automated specialized software. Data were analyzed applying Kolmogorov-Smirnov, Mann-Whitney U test, and Fisher’s exact test. Level of significance was set at p < 0.05. Results Convergence angle was above optimum in both groups, but significantly larger for group IS (p < 0.001). Marginal design was more ideal in group IS concerning the absence of featheredge design (p < 0.001) and reverse bevel (p = 0.211). Marginal substance reduction was closer to prerequisites for all-ceramic restorations in group IS (p < 0.001). Finish lines were more homogeneous in group IS regarding the uniformity of their course (p < 0.001). Undercuts were more frequently found in group ID than in group IS (p < 0.001). Conclusions Intraoral scanning of prepared teeth has positive impact on the quality of preparations for all-ceramic single crowns regarding marginal substance reduction, marginal design, homogeneity of the finish line, and undercuts. Clinical relevance Accurate preparation design represents a fundamental condition for success of ceramic crowns. Since there is potential for optimization, intraoral scanning might enhance preparation quality providing instant visual feedback.
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Nenciu, Florin, Maria Paraschiv, Radu Kuncser, Constantin Stan, Diana Cocarta, and Valentin Nicolae Vladut. "High-Grade Chemicals and Biofuels Produced from Marginal Lands Using an Integrated Approach of Alcoholic Fermentation and Pyrolysis of Sweet Sorghum Biomass Residues." Sustainability 14, no. 1 (December 31, 2021): 402. http://dx.doi.org/10.3390/su14010402.

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New global directions align agricultural land resources towards food production; therefore, marginal lands could provide opportunities for second-generation energy crops, assuming that in the difficult conditions of plant development, productivity can be maintained at relatively high levels. Sustainable bioenergy production on marginal lands represents an ambitious objective, offering high-quality biofuels without competing with the agri-food industry, since it allows successful feedstock production to be performed on unmanaged areas. However, marginal land feedstock production generally shows several agronomic, techno-economic, and methodological challenges, leading to decreases in the obtained quantities of biomass and profitability. Sweet Sorghum is a technical plant that has the needed qualities to produce large amounts of biofuels on marginal lands. It is a high biomass- and sugar-yielding crop, characterized by a high photosynthetic efficiency and low fertilizer requirement, is resistant to drought, and adapts well to different climate areas. Marginal lands and contaminated soils provide a favorable development environment for plants such as sweet sorghum; however, in-depth research studies on biomass productivity must be carried out, as well as advanced quality evaluation of the products, in order to develop combined technologies that use resources efficiently. The present study starts with a comparative evaluation of two sweet sorghum crops established on both marginal and regular lands, assessing plant development characteristics and juice production, and an evaluation of bioethanol generation potential. The vegetal wastes resulting from the processing were treated by pyrolysis, with the aim of maximizing the productivity of high-quality liquid biofuels and chemicals. The charcoal obtained in the thermal processes was considered as an amendment of the soil so that marginal land quality could be improved over time.
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Edstrom*, John P., William Krueger, and Wilbur Reil. "English Walnut Production on Marginal Soils." HortScience 39, no. 4 (July 2004): 857D—857. http://dx.doi.org/10.21273/hortsci.39.4.857d.

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Orchard hedgerow production systems have been used successfully in fruit and nut crops in California for decades to enhance yield, particularly in the early years of production. English walnuts (Juglans regia) are compatible with hedgerow techniques under prime soil conditions but are thought to require deep well drained soil to be commercially productive. Combining the production techniques of micro-irrigation, close spacing, minimal pruning and frequent fertilization in almonds has improved yield substantially on soils exhibiting a shallow, course textured topsoil underlain with a dense clay layer. Paradox hybrid rootstock (J. regia × J. hindsii) has shown greater tolerance to root lesion nematodes and heavier textured or poorly drained soils than Northern California Black (J. hindsii). Fourteen years of evaluation (1986-99) using `Chandler' and `Howard' Ctvs English walnuts in a replicated field trial on marginal soil has shown that 1) yields of 6700 kg·ha-1 (inshell) are attainable under these substandard soil conditions 2) Paradox hybrid rootstock out-yields Northern California Black by 30% on both cultivars tested, 3) kernels of high commercial quality for can be produced for both cultivars and 4) slip plow soil modifications may not improve tree growth, yield or crop quality in drip irrigated walnut hedgerow plantings.
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Brescia, Stephanie A., and Cara L. Cuite. "Underestimating College Student Food Insecurity: Marginally Food Secure Students May Not Be Food Secure." Nutrients 14, no. 15 (July 29, 2022): 3142. http://dx.doi.org/10.3390/nu14153142.

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The purpose of this study was to understand the demographic, student, financial, and academic differences between marginally food secure college students and students with high, low, or very low food security (FS). Unlike highly food secure students, marginally food secure students worry about the quantity and quality of their food, yet they are classified in the same category as highly food secure individuals as per the United States Department of Agriculture (USDA) reporting standards. To investigate marginal FS among college students, a cross-sectional online survey was administered at a large, public, research university in the Northeastern United States. A largely representative sample of 6823 undergraduate students completed the survey with a 19.7% response rate. Self-reported level of FS was measured using the validated USDA 10-item FS survey module. Independent variables, such as demographic and student characteristics and cumulative grade point average (GPA), were gathered from institutional databases, and self-reported mechanisms of financing education were measured using a novel scale. Results from the multinomial logistic regression revealed statistically significant differences in GPA between students with marginal and high FS (p < 0.001), but not between students with marginal and low FS (p = 0.31). This work has implications beyond college students and suggests that marginally food secure populations should not be labeled as food secure.
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Wang, Baodong, Linping Xie, and Xia Sun. "Water Quality in Marginal Seas off China in the Last Two Decades." International Journal of Oceanography 2011 (May 18, 2011): 1–6. http://dx.doi.org/10.1155/2011/731828.

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Based on historical data, variations in seawater quality and pollutant origins in marginal seas off China in the recent two decades are overviewed. Analysis shows that the total area of nonclean water was increasing continuously in the 1990s, but it has been decreasing since 2000; however, the total polluted area (sum of areas of slightly, medium, and heavily polluted waters) in China's standard fluctuated without a clear trend of decline or increase, indicating that although the increasing trend of marine environmental pollution has been kept effectively within certain limits, seawater quality has not been improved essentially in marginal seas off China. Furthermore, the occurrence frequency and affected area of HABs increased rapidly in marginal seas off China in the last 20 years. The amount of industrial and municipal discharges from the mainland China increased from the end of the 1980s to the end of the 1990s but decreased in the 2010s whereas riverine input of nutrients and pollutants from marine sources increased continuously.
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Smith, Andrew S. J., and Manuel Ojeda Cabral. "Is higher quality always costly? Marginal costs of quality: Theory and application to railway punctuality." Transportation Research Part A: Policy and Practice 157 (March 2022): 258–73. http://dx.doi.org/10.1016/j.tra.2022.01.007.

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Hou, Kun, and Xia Xu. "Evaluation of the Influence between Local Meteorology and Air Quality in Beijing Using Generalized Additive Models." Atmosphere 13, no. 1 (December 24, 2021): 24. http://dx.doi.org/10.3390/atmos13010024.

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Previous studies have confirmed the inextricable connection between meteorological factors and air pollutants. This study presents the complex nonlinear relationship between meteorological variables and four major air pollutants under high-concentration air pollution in Beijing. The generalized additive model combined with marginal effects is used for quantitative analysis. After controlling the confounding factors such as long-term trends, seasonality and spatio-temporal deviation, the final fitting results exhibit that temperature, relative humidity and visibility are the most significant meteorological variables associating with PM2.5 concentration, and the marginal effect reaches 80%, −23% and 270%, respectively. Temperature and relative humidity are the most significant variables for SO2, and the marginal effect reaches 15% and 7%. The most significant variables for O3 are temperature and solar radiation, with marginal effect of up to 70% and 8%. Atmospheric pressure and temperature results in a positive effect on CO, and the marginal effect can reach 18% and 80%. All these indicate that local meteorological variables are a significant driving factor for air quality in Beijing. Other variables, such as wind speed, visibility, and precipitation, display some influence on air pollutants, but have less explanatory power in the model. Overall, our study provides a better understanding of the relationship between local meteorological variables and air quality, as well as an insight into how climate change affects air quality.
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Bekkerman, Anton, Gary W. Brester, and Tyrel J. McDonald. "A Semiparametric Approach to Analyzing Differentiated Agricultural Products." Journal of Agricultural and Applied Economics 45, no. 1 (February 2013): 79–94. http://dx.doi.org/10.1017/s1074070800004594.

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When consumers have heterogeneous perceptions about product quality, traditional parametric methods may not provide accurate marginal valuation estimates of a product's characteristics. A quantile regression framework can be used to estimate valuations of product characteristics when quality perceptions are not homogeneous. Semiparametric quantile regressions provide identification and quantification of heterogeneous marginal valuation effects across a conditional price distribution. Using purchase price data from a bull auction, we show that there are nonconstant marginal valuations of bull carcass and growth traits. Improved understanding of product characteristic valuations across differentiated market segments can help producers develop more cost-effective management strategies.
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Karaman, S., and F. Yavuz. "Hedonic price analysis of the quality characteristics of Anatolian hard red wheat." Agricultural Economics (Zemědělská ekonomika) 60, No. 10 (October 21, 2014): 469–78. http://dx.doi.org/10.17221/37/2014-agricecon.

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The study analyses the relations between the quality characteristics and price of the Anatolian Hard Red Wheat. It uses a data set consisting of the price and eight quality characteristics of the Anatolian Hard Red Wheat traded in spot transaction in each month of 2011 in the Polatli Commodity Exchange. Marginal implicit values of the quality characteristics of the Anatolian Red Hard Wheat traded in the spot market of the Polatli Commodity Exchange are determined through the hedonic price model. This model is estimated from the linear-log functional form. Results of the hedonic price model demonstrate that the quality characteristics, which are statistically significant in the determination of price, namely, the protein content, the hectolitre weight, and the grain content damaged by pests and wheat bugs, are important factors in the purchasing decisions of flour millers. As the protein content and the hectolitre weight of wheat increase by 1%, the price increases by TL 0.005 and TL 0.006, respectively. As the grain content damaged by pests and wheat bugs increases by 1%, the price of wheat drops by TL 0.0002. These marginal implicit values are expected to encourage wheat producers to produce the higher quality wheat. &nbsp;
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Lima, Juliana Domingues, Fernanda Emiko Fukunaga, Eduardo Nardini Gomes, Danilo Eduardo Rozane, Silvia Helena Modenese Gorla da Silva, Wilson da Silva Moraes, and Cibelle Tamiris de Oliveira. "Fluctuations of Production and Quality of Bananas Under Marginal Tropical Climate." Journal of Agricultural Science 11, no. 14 (August 31, 2019): 108. http://dx.doi.org/10.5539/jas.v11n14p108.

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The knowledge of the inter-seasonal fluctuations in characteristics of fruit quality and production is important for management of plants, prediction of yield and marketing strategies. This study aims to evaluate how the climatic conditions prevailing in the month of harvest impact bunch mass and variability of the size and color of the banana fruit &lsquo;Nanica&rsquo; and &lsquo;Prata&rsquo; cultivated under marginal tropical climate. The experiments were carried in Registro, Ribeira Valley region, S&atilde;o Paulo, Brazil, in a completely randomized design with 24 treatments (months of bunch harvest) and ten replications, for each cultivar. Cyclic seasonal fluctuations in production were found in for the two cultivars, with the lowest bunch mass (BM), fruit size consistently recorded between July and February associated with lower global solar radiation (Rad) and temperature (T) of the harvest month, but not precipitation (Ppt). The extension of monthly fluctuations in BM were similar to &lsquo;Prata&rsquo; (18.95&plusmn;3.31 kg) and &lsquo;Nanica&rsquo; (29.51&plusmn;4.69 kg). Independent of the harvest month, there was a trend of greater variability for fruit length (FL) and lower for fruit diameter (FD) between fruits of the different positions in the bunch. The correlations between Rad or T of harvest month with BM, FL, FD and SL were all positive. For both cultivars, the shelf life (SL) was longer for fruits of the last hand. There were also positive correlations between Rad or T with SL. The decrease of peel color characteristics of the &lsquo;Nanica&rsquo; fruit was associated with cold fronts from autumn to spring and chilling injury, with higher intensity in the last hand.
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37

Briceno, J., P. Lopez-Cillero, S. Rufian, C. Diaz-Iglesias, G. Solorzano, J. Padillo, M. De la Mata, and C. Pera. "Impact of marginal quality donors on the outcome of liver transplantation." Transplantation Proceedings 29, no. 1-2 (February 1997): 477–80. http://dx.doi.org/10.1016/s0041-1345(96)00213-8.

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38

Keeling, Andrew, Jinhua Wu, and Marco Ferrari. "Confounding factors affecting the marginal quality of an intra-oral scan." Journal of Dentistry 59 (April 2017): 33–40. http://dx.doi.org/10.1016/j.jdent.2017.02.003.

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39

Hosgood, S. A., A. D. Barlow, J. P. Hunter, and M. L. Nicholson. "Ex vivonormothermic perfusion for quality assessment of marginal donor kidney transplants." British Journal of Surgery 102, no. 11 (August 27, 2015): 1433–40. http://dx.doi.org/10.1002/bjs.9894.

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40

Kirk, Sara FL, Stefan Kuhle, Jessie-Lee D. McIsaac, Patty L. Williams, Melissa Rossiter, Arto Ohinmaa, and Paul J. Veugelers. "Food security status among grade 5 students in Nova Scotia, Canada and its association with health outcomes." Public Health Nutrition 18, no. 16 (July 30, 2014): 2943–51. http://dx.doi.org/10.1017/s1368980014001414.

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AbstractObjectiveFood security (FS) exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their needs. The present research sought to determine whether students from households experiencing moderate or severe food insecurity (FI) had poorer diet quality, higher body weights and poorer psychosocial outcomes than students from households classed as having high FS or marginal FI status.DesignPopulation-based survey conducted in schools. Multiple regression analysis was used to explore associations between FS status (high FS; marginal, moderate, severe FI), dietary behaviours and intake, and health-related outcomes (body weight, quality of life, mood, peer relationships, externalizing problems).SettingNova Scotia, Canada.SubjectsGrade 5 students (n5853), aged 10–11 years, with complete information on FS status and student outcomes.ResultsIn this sample, rates of household FS were 73·5 % (high FS), 8·3 % (marginal FI) 10·2 % (moderate FI) and 7·1 % (severe FI status). Students living in households experiencing moderate or severe FI had poorer diet quality, higher BMI and poorer psychosocial outcomes than students classed as having high FS or marginal FI.ConclusionsThese findings provide important evidence for policy makers on the prevalence of FI among families in Nova Scotia with grade 5 children and its relationship with childhood nutrition, psychosocial and quality of life factors, and weight status.
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41

Doriguêtto, Paulo Victor Teixeira, Daniela de Almeida, Carolina Oliveira de Lima, Ricardo Tadeu Lopes, and Karina Lopes Devito. "Assessment of marginal gaps and image quality of crowns made of two different restorative materials: An in vitro study using CBCT images." Journal of Dental Research, Dental Clinics, Dental Prospects 16, no. 4 (December 30, 2022): 243–50. http://dx.doi.org/10.34172/joddd.2022.039.

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Background. The present study assessed the quality of images and the presence of marginal gaps on cone-beam computed tomography (CBCT) images of teeth restored with all-ceramic and metal-ceramic crowns and compared the gap sizes observed on CBCT images with those obtained on micro-CT images. Methods. Thirty teeth restored with metal-ceramic and all-ceramic crowns, properly adapted and with gaps of 0.30 and 0.50 mm, were submitted to micro-CT and CBCT scans. Linear measurements corresponding to the marginal gap (MG) and the absolute marginal discrepancy (AMD) were obtained. The objective assessment of the quality of CBCT images was performed using the contrast-to-noise ratio (CNR), and the subjective assessment was defined by the diagnoses made by five examiners regarding the presence or absence of gaps. Results. The measurements were always higher for CBCT, with a significant difference regarding AMD. No significant difference in image quality was observed using CNR between the crowns tested. Low accuracy and sensitivity values could be observed for both crowns. Conclusion. Marginal mismatch measures were overestimated in CBCT images. No difference in image quality was observed between the crowns. The correct diagnosis of gaps was considered low, irrespective of crown type and gap size.
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42

V. Geshoska, Katerina, and Jagoda Bajevska. "Effect of manufacturing protocol on the internal fit and marginal discrepancy of metal ceramic and full ceramic dental crowns." Macedonian Pharmaceutical Bulletin 63, no. 01 (2018): 69–74. http://dx.doi.org/10.33320/maced.pharm.bull.2017.63.01.008.

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The accuracy of internal fit and marginal precision plays important role of clinical quality and success of dental crowns. Complications caused by marginal discrepancies such as caries, gingivitis, hypersensitivity are highlighted in dental literature. Despite marginal fit, internal fit and precision have a significant role in the persistence of full ceramic and metal ceramic crowns. As the technology evolves, it’s questionable which impression and manufacturing method is giving most accurate dental crowns. Therefore, the main purpose of this study is to get some information and data about marginal and internal fitting of dental crowns made by conventional, two-phase impression technique with polyvinyl siloxanes, and using different manufacturing process. Keywords: internal fit, marginal discrepancy, metal ceramic, full ceramic crowns
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43

Shi, Wei, and Jun Xia. "Combined risk assessment of nonstationary monthly water quality based on Markov chain and time-varying copula." Water Science and Technology 75, no. 3 (November 30, 2016): 693–704. http://dx.doi.org/10.2166/wst.2016.553.

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Water quality risk management is a global hot research linkage with the sustainable water resource development. Ammonium nitrogen (NH3-N) and permanganate index (CODMn) as the focus indicators in Huai River Basin, are selected to reveal their joint transition laws based on Markov theory. The time-varying moments model with either time or land cover index as explanatory variables is applied to build the time-varying marginal distributions of water quality time series. Time-varying copula model, which takes the non-stationarity in the marginal distribution and/or the time variation in dependence structure between water quality series into consideration, is constructed to describe a bivariate frequency analysis for NH3-N and CODMn series at the same monitoring gauge. The larger first-order Markov joint transition probability indicates water quality state Class Vw, Class IV and Class III will occur easily in the water body of Bengbu Sluice. Both marginal distribution and copula models are nonstationary, and the explanatory variable time yields better performance than land cover index in describing the non-stationarities in the marginal distributions. In modelling the dependence structure changes, time-varying copula has a better fitting performance than the copula with the constant or the time-trend dependence parameter. The largest synchronous encounter risk probability of NH3-N and CODMn simultaneously reaching Class V is 50.61%, while the asynchronous encounter risk probability is largest when NH3-N and CODMn is inferior to class V and class IV water quality standards, respectively.
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44

Greenstone, Michael, and B. Kelsey Jack. "Envirodevonomics: A Research Agenda for an Emerging Field." Journal of Economic Literature 53, no. 1 (March 1, 2015): 5–42. http://dx.doi.org/10.1257/jel.53.1.5.

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Environmental quality in many developing countries is poor and generates substantial health and productivity costs. However, the few existing measures of marginal willingness to pay (MWTP) for environmental quality improvements indicate low valuations by affected households. This paper argues that this seeming paradox is the central puzzle at the intersection of environmental and development economics: Given poor environmental quality and high health burdens in developing countries, why is MWTP seemingly so low? We develop a conceptual framework for understanding this puzzle and propose four potential explanations for why environmental quality is so poor: (1) due to low income levels, individuals value increases in income more than marginal improvements in environmental quality; (2) the marginal costs of environmental quality improvements are high; (3) political economy factors undermine efficient policymaking; and (4) market failures such as weak property rights and missing capital markets distort MWTP for environmental quality. We review the literature on each explanation and discuss how the framework applies to climate change, which is perhaps the most important issue at the intersection of environment and development economics. The paper concludes with a list of promising and unanswered research questions for the emerging sub-field of “envirodevonomics.” (JEL I15, O10, O44, Q50)
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45

Leite, Rafael Olivé. "More is exponentially less: marginal utility in critical care research." Journal of Evidence-Based Healthcare 4 (November 4, 2022): e4722. http://dx.doi.org/10.17267/2675-021xevidence.2022.e4722.

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BACKGROUND: Randomized clinical trials (RCT) in critical care mostly return negative results. The research community discusses strategies to improve RCTs design. METHODS: This paper presents a theoretical framework based on marginal utility to treat the problems of hypothesis generation and treatment effects valuation and presents recently published high-quality studies as instances where such a framework predicts irrelevant findings. RESULTS: Blindness to marginal utility, i.e., inobservance of the marginal utility of the proposed intervention, is common in critical care RCTs. CONCLUSION: Critical care RCTs are usually blind to marginal utility and are, therefore, prone to produce irrelevant findings.
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46

Li, Wentao, Douglas J. Wilson, Tam J. Larkin, and Philippa M. Black. "Permanent Strain Behavior of Marginal Granular Material." Transportation Research Record: Journal of the Transportation Research Board 2655, no. 1 (January 2017): 54–63. http://dx.doi.org/10.3141/2655-08.

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To better understand the marginality of marginal granular materials (i.e., an aggregate that does not fully meet a premium quality specification), this study investigated the permanent strain behavior of two granular materials with different geological and mineralogical characteristics under repeated loading and different moisture conditions. The secant permanent strain rate and shakedown approach were used to analyze the permanent strain behavior of the materials. A one-dimensional swelling test was used to explain the mechanism of the permanent strain behavior of the soaked materials under repeated loading. The results show that compared with a New Zealand premium quality aggregate, the marginal aggregate exhibits a more significant increase in the cumulative permanent strain and the secant permanent strain rate after the 4-day soaking process. The results of the shakedown approach illustrate that the marginal aggregate performs reasonably well to resist permanent deformation in a dry condition, but the performance will considerably deteriorate when in contact with water under high stress. This change is a result of the presence of swelling clay minerals (e.g., smectite) in the marginal aggregates. The result of the one-dimensional swelling test indicates the high swelling potential of marginal aggregate, which provides an explanation for its poorer resistance to permanent strain. The marginal aggregate gains undesirable internal lubrication when surrounded by (moist) swelling clay mineral particles; thus, its shear strength reduces and permanent strain rate increases under repeated loading.
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47

Czerny, Mirosława. "The Permanence of Socio-Economically Marginal Structures Within Urban Space: The Example of Bogotá." Quaestiones Geographicae 30, no. 4 (December 1, 2011): 47–54. http://dx.doi.org/10.2478/v10117-011-0037-6.

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The Permanence of Socio-Economically Marginal Structures Within Urban Space: The Example of Bogotá The subject of this paper is an analysis of marginal spatial development processes taking place in Bogotá, one of the largest cities in the Southern Hemisphere. Bogotá, the capital of Colombia, situated on a high plateau (Sabana de Bogotá) at over 2,500 metres above sea-level, has currently approximately 8 million inhabitants. In Bogotá, as in any major South American city, we find the characteristic, highly pronounced diversification of urban space in terms of quality, urban landscape features, and living conditions. Marginal areas in Bogotá, characterised by a low quality of urban space, can be divided into two types, their origin and attributes linked to the general social processes that have taken place here in the 20th century. They are distinguished as follows: (a) marginal districts on the outskirts of the city, resulting from a period of dynamic and unplanned urbanisation, from the 1970s until now; and (b) marginal districts in the centre of the city. This article aims to show the mechanisms that contribute to the formation of and changes in these two types of urban space.
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48

Veiga, André, and E. Glen Weyl. "Product Design in Selection Markets *." Quarterly Journal of Economics 131, no. 2 (February 24, 2016): 1007–56. http://dx.doi.org/10.1093/qje/qjw007.

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Abstract In selection markets, where the cost of serving consumers is heterogeneous and noncontractible, nonprice product features allow a firm to sort profitable from unprofitable consumers. An example of this “sorting by quality” is the use of down payments to dissuade borrowers who are unlikely to repay. We study a model in which consumers have multidimensional types and a firm offers a single product of endogenous quality, as in Spence (1975) . These two ingredients generate a novel sorting incentive in a firm’s first-order condition for quality, which is a simple ratio. The denominator is marginal consumer surplus, a measure of market power. The numerator is the covariance, among marginal consumers, between marginal willingness to pay for quality and cost to the firm. We provide conditions under which this term is signed and contrast the sorting incentives of a profit-maximizer and a social planner. We then use this characterization to quantify the importance of sorting empirically in subprime auto lending, analytically sign its impact in a model of add-on pricing, and calibrate optimal competition policy in health insurance markets.
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49

Hatami, Kianoosh, Jaime E. Granados, Danial Esmaili, and Gerald A. Miller. "Reinforcement Pullout Capacity in Mechanically Stabilized Earth Walls with Marginal-Quality Soils." Transportation Research Record: Journal of the Transportation Research Board 2363, no. 1 (January 2013): 66–74. http://dx.doi.org/10.3141/2363-08.

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Pullout capacity of geotextile reinforcement is an important consideration in the analysis of internal stability of reinforced soil structures, especially those constructed with marginal soils. Precipitation, ground water infiltration, and seasonal variations of water content during the construction process or service life of the structure could result in significant reductions in the matric suction and lead to a reduction in the strength of the soil–geotextile interface. Consequently, the reinforced soil structure may experience unacceptable deformations or even failure during its construction or postconstruction periods. The loss of matric suction in the soil influences both the shear strength of the soil and the soil–reinforcement interface. However, the focus of this study was merely on the latter. Nine pullout tests and 18 interface shear tests were performed to measure the pullout resistance of a reinforcement geotextile in a marginal soil that was compacted at different gravimetric water contents (GWCs). The marginal soil was selected to meet the limiting requirements of the National Concrete Masonry Association guidelines for segmental retaining walls with respect to fines content, gradation, and plasticity. The range of GWC values investigated varied from the dry to the wet side of the optimum moisture content of the soil. The matric suction in the soil was measured to evaluate its influence on the soil–reinforcement interface shear strength. A moisture reduction factor is proposed to account for the reduction in the soil–geotextile interface strength as a result of the loss in matric suction.
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50

Kauffman, Gerald J. "Benefit-cost analysis of water quality policy and criteria in the Delaware River." Water Policy 22, no. 3 (May 13, 2020): 313–27. http://dx.doi.org/10.2166/wp.2020.017.

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Abstract This research conducts a benefit-cost analysis of water policies to reach an optimal level of dissolved oxygen (DO) to meet year-round fishable water quality criteria in the Delaware River. A watershed pollutant load model is utilized to estimate marginal cost curves of water quality improvements to meet a more protective year-round fishable standard and annual benefits are defined to achieve future DO criteria in the Delaware River. The most cost-effective DO standard is 4.5 mg/L defined by the point where the marginal benefits of willingness to pay (WTP) for improved water quality equals the marginal costs of pollution reduction. This optimal criteria (4.5 mg/L) can be achieved at a cost of $150 million with benefits ranging from $250 to $700 million/year. While a future DO standard of 4.5 mg/L reflects an economically efficient level of water quality, this DO criteria is less protective than the level of 5–6 mg/L needed to protect anadromous fish such as the Atlantic sturgeon. The policy to reach a DO level of 6 mg/L (at 80% DO saturation) may be difficult to achieve at summer water temperatures that approach 30 °C in the Delaware River at Philadelphia.
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