A New Argument Against Critical-Level Utilitarianism

Utilitas ◽  
2021 ◽  
pp. 1-18
Author(s):  
Patrick Williamson
Keyword(s):  
Critical Level ◽  
Positive Contribution ◽  
Critical Levels ◽  
Critical Range ◽  
Relative Threshold

Abstract One prominent welfarist axiology, critical-level utilitarianism, says that individual lives must surpass a specified ‘critical level’ in order to make a positive contribution to the comparative status of a given population. In this article I develop a new dilemma for critical-level utilitarians. When comparatively evaluating populations composed of different species, critical-level utilitarians must decide whether the critical level is a universal threshold or whether the critical level is a species-relative threshold. I argue that both thresholds lead to a range of axiological puzzles and objections as yet undiscussed within the literature, and therefore conclude that critical-level utilitarianism should not be taken as a morally plausible welfarist axiology. I show that certain competitive formulations of critical range utilitarianism are subject to the argument too, and that further attempts to relativise critical levels to a particular group or category of welfare bearer (in particular, individual-relative critical levels) are unsustainable.

scholarly journals Boron nutrition and yield of alfalfa cultivar crioula in relation to boron supply

2004 ◽  
Vol 61 (5) ◽  
pp. 496-500 ◽  
Author(s):  
Anacleto Ranulfo dos Santos ◽  
Waldssimiler Teixeira de Mattos ◽  
Ana Aparecida da Silva Almeida ◽  
Francisco Antonio Monteiro ◽  
Beatriz Dias Corrêa ◽  
...  
Keyword(s):  
Dry Matter ◽  
Boron Concentration ◽  
Critical Level ◽  
External Solution ◽  
Dry Mass ◽  
Dry Matter Accumulation ◽  
Critical Levels ◽  
Production And Distribution ◽  
Plant Data ◽  
South Brazil

Alfalfa cultivar Crioula (Medicago sativa cv. Crioula) is grown in South Brazil and only a few studies on the plants' boron requirement are available. A greenhouse experiment was carried out with alfalfa to measure boron acquisition, production and distribution in the plant; data on critical level and production potentials were recorded. Plants were grown in ground quartz added with 1 L of solution, with the following boron rates: 0, 0.0625, 0.125, 0.25, 0.50, 1.00, and 2.00 mg L-1. Plants were harvested at 46 days of growth. Forage dry mass was increased by boron supply and dry matter accumulation was considerably low in control. Boron concentration in the leaves was higher than in the stems or roots. Boron utilization from the external solution reached 90% at 0.0625 mg L-1 and sharply decreased with further increasing boron rates. Boron concentration and content in the leaves and in plant tops were at maximum when applied boron was between 1.5 and 1.6 mg L-1. Critical levels of boron in plant were 61 mg kg-1 in the leaves and 39 mg kg-1 in plant tops for this cultivar of alfalfa.

scholarly journals Phosphorus fertilization and growth of buffel grass (Cenchrus ciliares L.) cultivars

2015 ◽  
Vol 19 (1) ◽  
pp. 34-38
Author(s):  
Vanderlise Giongo ◽  
Alessandra M. Salviano ◽  
Betina R. C. dos Santos ◽  
Emylly F. Leal
Keyword(s):  
Critical Level ◽  
Dry Mass ◽  
Phosphorus Fertilization ◽  
Critical Levels ◽  
Buffel Grass ◽  
P Accumulation ◽  
P Content ◽  
Phosphorus Requirement ◽  
Set Up

Phosphorus (P) plays an important role in the growth of root system as well as the tillering grass, being fundamental to increase the productivity of these species. The aim of this study was to evaluate the development of buffel grass cultivars and establish critical values of P in plant and soil. The experimental set up was a 4 x 5 factorial scheme (four Cenchrus ciliaris cvs.: Biloela, Aridus, CPATSA 7754 and Pusa Giant, and five doses of P2O5 - 0, 30, 60, 90 and 120 kg ha-1) with four replications. After 90 days of cultivation, dry mass of shoot (DMS) and root (DMR) production and the P accumulation (Pacc) were determined. Soil samples to determine the P content and determination of the critical level (CriLev) were also collected. The cv. Biloela presented lower DMR and DMS production compared to the other cultivars. The cultivares Biloela, Pusa Giant and Aridus showed different critical levels of P in soil and plant, obtained in the greenhouse showing that they have different requirement of this nutrient for their growth. The cultivar CPATSA 7754 showed higher phosphorus requirement and did not permit to establish critical levels with doses used in the present study.

The relationship between the yields of eight varieties of Nigerian maize and content of nitrogen, phosphorus and potassium in the leaf at flowering stage

1972 ◽  
Vol 79 (3) ◽  
pp. 391-396 ◽  
Author(s):  
Akinola A. Agboola
Keyword(s):  
Grain Yield ◽  
Critical Level ◽  
Nutrient Content ◽  
Critical Levels ◽  
Flowering Stage ◽  
Growing Seasons ◽  
Phosphorus And Potassium ◽  
High Yielding Varieties ◽  
The Relationship ◽  
Nitrogen Phosphorus

SUMMARYStudies of the relationship between yield and content of N, P and K in the ear leaf of eight varieties of Nigerian maize, tested for three growing seasons, indicated that the varieties have different critical nutrient levels, although the values obtained for individual varieties were not significantly different from the pooled average critical level for any of the nutrients. The critical levels ranged from 2·85 to 3·19% N, 0·20 to 0·27% P and 2·06 to 2·60% K, while their pooled averages were 3·10% N, 0·23% P and 2·44% K.High ear leaf nutrient content was not a guarantee of high grain yield, and ear leaf nutrient values of low-yielding varieties were similar to those of the high-yielding varieties.

scholarly journals Partitioning of injuries caused by winter, fungal diseases and viral infections in cereals

1993 ◽  
Vol 2 (4) ◽  
pp. 353-356
Author(s):  
Jari Peltonen
Keyword(s):  
Spring Wheat ◽  
Viral Infections ◽  
Critical Level ◽  
Barley Yellow Dwarf Virus ◽  
Yield Reduction ◽  
Winter Rye ◽  
Critical Levels ◽  
Barley Yellow Dwarf ◽  
Oat Cultivars ◽  
Yellow Dwarf Virus

The objective of this study was to clarify whether the critical levels of winter damage, viral infections and foliar diseases of cereals could be established by the Cate-Nelson procedure. This information would help the State Granary representatives and computer modelists, as well as farmers and consultants to understand the yearly variations in grain yields of cereals. Three winter rye, spring wheat and oat cultivars were used. The severity of leaf diseases and percentages of winter damage were observed visually. When winter damage exceeds 19%, a yield reduction of 44% (1804 kg ha-1) in winter rye may be expected. The critical level of Septoria nodorum infection in spring wheat was 37%. Above this critical level a yield reduction of 33% (1393 kg ha-1) was estimated. In oat canopy an area of > 38% infected by barley yellow dwarf virus (BYDV) decreased the grain yield significantly by 30% (1718 kg ha-1).

scholarly journals Soil chemical characteristics, biomass production and levels of nutrient and heavy metals in corn plants according to doses of steel slag and limestone

Revista CERES ◽  
2016 ◽  
Vol 63 (6) ◽  
pp. 879-886
Author(s):  
Luiz Carlos Santos Caetano ◽  
Luiz Carlos Prezotti ◽  
Bevaldo Martins Pacheco ◽  
Rogério Carvalho Guarçoni
Keyword(s):  
Heavy Metals ◽  
Biomass Production ◽  
Dry Matter ◽  
Soil Acidity ◽  
Critical Level ◽  
Steel Slag ◽  
Chemical Characteristics ◽  
Critical Levels ◽  
Corn Plants ◽  
Over Time

ABSTRACT Steel slag presents potential for neutralizing the soil acidity instead of limestone and for supplying nutrients for plants. The objective of this work was to study the effect of steel slag on soil chemical characteristics, biomass production, and contents of nutrients and of heavy metals on dry matter of corn plants. The levels of P, K, Na, Ca, Mg, Cu, Fe, Zn, Mn, Si, Cd, Cr, Pb, and Ni were determined in steel slag and limestone (for comparison purposes) and the growth of corn plants under increasing doses of slag and limestone (0 to 10 t ha-1) was evaluated. Steel slag presented higher levels of P, Fe, Zn, Mn, and Si when compared with limestone. No difference was found in the content of heavy metals of slag and limestone, except for Cr, which was higher in the slag. Limestone provided the greatest increase of soil pH over time. Slag increased the content of P, Si, and soil micronutrient, while limestone was more efficient in increasing the content of Mg. The levels of heavy metals in the soil increased with the application of slag, but they remained below critical level within agricultural parameters. Slag and limestone presented a similar effect on the increase of the initial production of corn biomass. The levels of heavy metals in dry matter of corn plants under increasing doses of slag and limestone were below the critical levels of the toxicity of these elements on most plants.

scholarly journals Mountain Waves in Two-Layer Sheared Flows: Critical-Level Effects, Wave Reflection, and Drag Enhancement

2008 ◽  
Vol 65 (6) ◽  
pp. 1912-1926 ◽  
Author(s):  
Miguel A. C. Teixeira ◽  
Pedro M. A. Miranda ◽  
JoséL. Argaín
Keyword(s):  
Linear Theory ◽  
Shear Flows ◽  
Wave Reflection ◽  
Critical Level ◽  
Internal Gravity Waves ◽  
Wave Drag ◽  
Critical Levels ◽  
Nonlinear Processes ◽  
Mountain Waves ◽  
The Impact

Abstract Internal gravity waves generated in two-layer stratified shear flows over mountains are investigated here using linear theory and numerical simulations. The impact on the gravity wave drag of wind profiles with constant unidirectional or directional shear up to a certain height and zero shear above, with and without critical levels, is evaluated. This kind of wind profile, which is more realistic than the constant shear extending indefinitely assumed in many analytical studies, leads to important modifications in the drag behavior due to wave reflection at the shear discontinuity and wave filtering by critical levels. In inviscid, nonrotating, and hydrostatic conditions, linear theory predicts that the drag behaves asymmetrically for backward and forward shear flows. These differences primarily depend on the fraction of wavenumbers that pass through their critical level before they are reflected by the shear discontinuity. If this fraction is large, the drag variation is not too different from that predicted for an unbounded shear layer, while if it is small the differences are marked, with the drag being enhanced by a considerable factor at low Richardson numbers (Ri). The drag may be further enhanced by nonlinear processes, but its qualitative variation for relatively low Ri is essentially unchanged. However, nonlinear processes seem to interact constructively with shear, so that the drag for a noninfinite but relatively high Ri is considerably larger than the drag without any shear at all.

Reaction of zinc with soil affecting its availability to subterranean clover. 1. The relationship between critical concentrations of extractable zinc and properties of Australian soils responsive to applied zinc

Soil Research ◽  
1990 ◽  
Vol 28 (2) ◽  
pp. 293 ◽  
Author(s):  
RF Brennan ◽  
JW Gartrell
Keyword(s):  
Soil Property ◽  
Critical Level ◽  
Ammonium Oxalate ◽  
Subterranean Clover ◽  
Clay Content ◽  
Maximum Growth ◽  
Soil Types ◽  
Critical Levels ◽  
Wide Range ◽  
The Relationship

A number of glasshouse experiments were conducted in which subterranean clover cv. Nungarin was grown in pots of a wide range of Australian soils to which zinc was added. Levels of zinc extractable in DTPA and in ammonium oxalate were determined and related to the growth of clover. DPTA extractable zinc (ZnD) was found to be a reliable predictor of the response of subclover to zinc added to the soils. The critical levels of ZnD, determined for the maximum growth of subterranean clover were found to vary markedly among the soil types. No simple linear relationship between the critical ZnD levels and any one soil property were found. The ZnD critical levels were found to be related to the clay content (%) and pH (1 : 5 water). The selected model in a stepwise linear regression was: Y (DTPA critical level) = -0.087 + 0.039 pH, + 0.005 clay (%). For the non-responsive soils, ZnD was found to be above the calculated critical ZnD level.

Momentum transport by gravity waves in a perfectly conducting shear flow

1972 ◽  
Vol 54 (2) ◽  
pp. 217-240 ◽  
Author(s):  
N. Rudraiah ◽  
M. Venkatachalappa
Keyword(s):  
Magnetic Field ◽  
Gravity Waves ◽  
Critical Level ◽  
Critical Levels ◽  
Mean Flow ◽  
Critical Layers ◽  
The Mean ◽  
Pass Through ◽  
The Waves ◽  
Aligned Magnetic Field

Alfvén-gravitational waves propagating in a Boussinesq, inviscid, adiabatic, perfectly conducting fluid in the presence of a uniform aligned magnetic field in which the mean horizontal velocityU(z)depends on heightzonly are considered. The governing wave equation has three singularities, at the Doppler-shifted frequencies Ωd= 0, ± ΩA, where ΩAis the Alfvén frequency. Hence the effect of the Lorentz force is to introduce two more critical levels, called hydromagnetic critical levels, in addition to the hydrodynamic critical level. To study the influence of magnetic field on the attenuation of waves two situations, one concerning waves far away from the critical levels (i.e. Ωd[Gt ] ΩA) and the other waves at moderate distances from the critical levels (i.e. Ωd> ΩA), are investigated. In the former case, if the hydrodynamic Richardson numberJHexceeds one quarter the waves are attenuated by a factor exp{−2π(JH−¼)½} as they pass through the hydromagnetic critical levels, at which Ωd= ± ΩA, and momentum is transferred to the mean flow there. Whereas in the case of waves at moderate distances from the critical levels the ratio of momentum fluxes on either side of the hydromagnetic critical levels differ by a factor exp {−2π(J−¼)½}, whereJ(> ¼) is the algebraic sum of hydrodynamic and hydromagnetic Richardson numbers. Thus the solutions to the hydromagnetic system approach asymptotically those of the hydrodynamic system sufficiently far on either side of the magnetic critical layers, though their behaviour in the vicinity of such levels is quite dissimilar. There is no attenuation and momentum transfer to the mean flow across the hydrodynamic critical level, at which Ωd= 0. The general theory is applied to a particular problem of flow over a sinusoidal corrugation. This is significant in considering the propagation of Alfvén-gravity waves, in the presence of a geomagnetic field, from troposphere to ionosphere.

On the existence of critical levels, with applications to hydromagnetic waves

1973 ◽  
Vol 58 (4) ◽  
pp. 709-726 ◽  
Author(s):  
James F. McKenzie
Keyword(s):  
Magnetic Field ◽  
Wave Packet ◽  
Critical Level ◽  
Rotation Axis ◽  
The Other ◽  
Gravitational Acceleration ◽  
Critical Levels ◽  
Normal Surface ◽  
Hydromagnetic Waves ◽  
Wave Normal

It is proved that a critical level, at which a wave packet is neither reflected nor transmitted, can exist only if the wave normal curve, which is formed by taking the cross-section through the wave normal surface in the plane of propagation, possesses an asymptote which is parallel to the direction of variation of the properties of the medium through which the wave packet moves. This condition, when applied to various types of hydromagnetic waves (such as hydromagnetic waves of the inertial or gravity type, or slow magnetoacoustic waves), shows that critical levels for such waves can exist only if the direction of spatial variations of the medium is perpendicular to the ambient magnetic field. Provided that the angle between the gravitational acceleration, or the rotation axis, and the magnetic field is not zero, hydromagnetic critical levels, characteristic of the gravity or inertial type, act like ‘valves’ in the sense that the wave packet can pierce the critical level from one side and is captured from the other side. It is also pointed out that critical-level behaviour is to some extent a consequence of the WKBJ approximation since the other limit, namely when the waves feel an almost discontinuous behaviour in the properties of the medium, gives markedly different results, particularly in the presence of streaming, which can give rise to the phenomenon of wave amplification.

scholarly journals Nitrogen content, SPAD index and production of single head broccoli

2021 ◽  
Vol 39 (1) ◽  
pp. 52-57
Author(s):  
Sanzio M Vidigal ◽  
Mário Puiatti ◽  
Iza Paula de C Lopes ◽  
Maria Aparecida N Sediyama
Keyword(s):  
Experimental Design ◽  
Nutritional Status ◽  
Nitrogen Content ◽  
Nitrogen Fertilization ◽  
Critical Level ◽  
Critical Levels ◽  
N Content ◽  
Total N ◽  
Maximum Value ◽  
N Rates

ABSTRACT In the management of single head broccoli nitrogen fertilization, there is no study indicating the critical level and adequate range of N content and SPAD index in the leaves to evaluate the nitrogen nutritional status. This work was carried out in two consecutive years with control without N and three rates of N (150; 300 and 450 kg ha-1). The treatments were arranged in the experimental design of random blocks, with four replications. All productive characteristics were significantly influenced by N rates. The fresh inflorescence mass reached a maximum value of 822 g with 308 kg ha-1 N. The critical levels were 61.1 g kg-1 for total N foliar content and 71.31 ud SPAD at 40 DAT. The SPAD index presented high correlations with the total N content in the leaves (r = 0.93; p<0.034) and with the maximum fresh mass of the inflorescence (r = 0.99; p<0.001). The ranges of N content (low ≤52.5; medium 52.6 to 57.4; sufficient 57.5 to 61.1 and high >61.1 g kg-1) and SPAD index (low ≤68.48; medium 68.49 to 70.47; sufficient 70.48 to 71.31 and high >71.31 ud SPAD) are proposed for assessing the N nutritional status of single head broccoli.

Sign in / Sign up

Export Citation Format

Share Document