DEVELOPMENT OF A BARLEY YIELD EQUATION FOR CENTRAL ALBERTA. 1. EFFECTS OF SOIL AND FERTILIZER N AND P

Equations were derived relating yields of barley, grown on previously cropped land, to inputs of fertilizer nitrogen (NA) and phosphorus (PA) and to soil test values for nitrate nitrogen (NS) and extractable phosphorus (PS). The first model, Y = f (NA, PA), fitted to pooled data of 17 site-years, explained about 23% of yield variations. The second model, Y = f (NA, PA, NS, PS), fitted to the same data, explained 36–38%, depending on depth of sampling. When the optimal nitrogen applications obtained from the latter model were compared to the optimal nitrogen applications obtained from the first model applied to the individual site-years, the 30-cm sampling depth was found to be superior to the 15-cm depth; there was no further improvement by sampling to 61 cm. Our results indicated several ways in which the Alberta Soil Testing Laboratory could improve its fertilizer recommendations, namely: basing nitrogen recommendations on samples taken to 30 cm rather than 15 cm, adjusting recommended nitrogen applications according to level of PS, lowering the levels of phosphorus recommended for various levels of PS, and adjusting the nitrogen and phosphorus recommendations according to prices of fertilizers and barley. Much of the yield variation could not be explained by variations in applied and soil nutrients, indicating that other uncontrolled environmental variables, such as soil moisture and rainfall, should be introduced into the barley yield equations. Part 2 presents the methodology for introducing a "moisture stress" term.

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Skeleton weed (Chondrilla juncea) in the Victorian Mallee. 4. Effects of fallowing on wheat yields and weed populations

Australian Journal of Experimental Agriculture ◽

10.1071/ea9710313 ◽

1971 ◽

Vol 11 (50) ◽

pp. 313 ◽

Cited By ~ 2

Author(s):

GJ Wells

Keyword(s):

Soil Nitrogen ◽

Nitrate Nitrogen ◽

Wheat Yield ◽

Individual Response ◽

Phosphorus Fertilizer ◽

Nitrogen And Phosphorus ◽

Rainfall Distribution ◽

Weed Density ◽

Weed Growth ◽

The Individual

Experiments to compare the duration of fallows and the substitution of a 2,4-D spray for some fallow cultivations for wheat production on skeleton weed land were conducted in the Victorian Mallee from 1962 to 1966. Generally winter fallows outyielded spring fallows, commenced only two months later, and these in turn gave higher yields than an autumn-cultivated treatment. Compared with autumn cultivation, winter fallowing reduced skeleton weed density by an average of 49 per cent. Substituting a 2,4-D spray for some Gltivations had little effect on wheat yield, but improved the control of skeleton weed. Grain yield was determined primarily by the level of nitrate nitrogen in the surface 15 cm of soil before sowing, and this effect was attributed to the low soil nitrogen status found in skeleton weed situations. Soil moisture was conserved only occasionally, owing to the difficulty of controlling weed growth during the summer coupled with the variable rainfall distribution in the Mallee. Although a nitrogen and phosphorus fertilizer interaction was significant at all sites, neither the individual response nor the interaction was affected by fallow treatment.

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Effects of Soil and Management Factors on Fertilizer Responses and Yield of Irrigated Wheat in Iran

Experimental Agriculture ◽

10.1017/s0014479700005251 ◽

1972 ◽

Vol 8 (3) ◽

pp. 195-202

Author(s):

T. P. Abraham ◽

A. Hoobakht

Keyword(s):

Multiple Regression ◽

Yield Response ◽

Soil Test ◽

Soil Factors ◽

Nitrogen And Phosphorus ◽

Yield Data ◽

Nitrogen Response ◽

Yield Variation ◽

Multiple Regression Technique ◽

Irrigated Wheat

SUMMARYThe yield data obtained from fertilizer experiments conducted at 195 locations for three years were examined to study the relations between yield, response to nitrogen and phosphorus, soil test values, and number of irrigations, using multiple regression technique. Irrigation accounted for 20–36 per cent of the yield variation, whereas soil factors did not show appreciable effects. Nitrogen response was influenced by irrigation, while some soil factors affected response to phosphorus.

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Is it Worth CANVASing for CREDENCE? A Benefit-risk Analysis

Current Diabetes Reviews ◽

10.2174/1573399815666191025094733 ◽

2020 ◽

Vol 16 (5) ◽

pp. 509-514

Author(s):

Binayak Sinha ◽

Samit Ghosal

Keyword(s):

Adverse Events ◽

Fungal Infections ◽

Absolute Risk ◽

Pooled Analysis ◽

Major Adverse Cardiovascular Events ◽

Number Needed To Treat ◽

Pooled Data ◽

The Individual ◽

Fracture Risks ◽

Number Needed To Harm

Background and Aims: A number of significant positive and negative signals emerged from the CANVAS Program and CREDENCE trial with the use of canagliflozin. These signals are confusing. A Likelihood of being Helped of Harmed (LHH) analysis was conducted to determine the risk, benefit ratio associated with canagliflozin use and address the signals as a continuum. Materials &Methods: LHH was calculated from the number needed to treat (NNT) and number needed to harm (NNH) available from the absolute risk reductions reported with the outcomes of interest, in these two trials. Results: In the CANVAS Program, LHH for major adverse cardiovascular events (MACE) points at a significant benefit with canagliflozin use in comparison to amputation (1.65), fractures (1.65) and euglycaemic diabetic ketoacidosis (euDKA) (16.67) risks. Only genital fungal infections were significant more in both sexes (0.21-M and 0.1-F) when LHH was matched against the positive outcomes. In contrast, the hHF benefits were outweighed by amputation (0.95) and fracture risks (0.95). : In CREDENCE trial, the LHH for Primary composite, Renal composite and MACE, all supported the benefits in comparison to any adverse events encountered in the trial. : The LHH from pooled data (CANVAS Program and CREDENCE trial) was in favour of all the benefits (hHF and renal composites) except for MACE matched against amputation (0.66). Conclusion: The outcome benefits were in favour of canagliflozin in comparison to all reported adverse events, when hHF and renal composite were under consideration, in both the individual and pooled LHH analysis. However, the MACE benefits were overwhelmed by amputation risk in the pooled analysis.

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Interaction of Nitrogen and Phosphorus on Wheat Yield, N Use Efficiency and Soil Nitrate Nitrogen Distribution in the North China Plain

International Journal of Plant Production ◽

10.1007/s42106-020-00093-6 ◽

2020 ◽

Vol 14 (3) ◽

pp. 415-426

Author(s):

Yulu Chen ◽

Panpan Zhang ◽

Lifang Wang ◽

Geng Ma ◽

Zhuo Li ◽

...

Keyword(s):

North China Plain ◽

North China ◽

Nitrate Nitrogen ◽

Wheat Yield ◽

Soil Nitrate ◽

Nitrogen And Phosphorus ◽

The North ◽

The North China Plain ◽

Use Efficiency ◽

N Use

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Mechanism Analysis and Experimental Research on the Interception of Nitrogen and Phosphorus Pollutants by Gullies in Northern China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.3392 ◽

2011 ◽

Vol 250-253 ◽

pp. 3392-3396

Author(s):

Yu Jia Song ◽

Hui Qing Liu

Keyword(s):

Total Phosphorus ◽

Nitrate Nitrogen ◽

Northern China ◽

Careful Analysis ◽

Ammonia Nitrogen ◽

Mechanism Analysis ◽

Nitrogen And Phosphorus ◽

Urban Sewage ◽

Control Section ◽

Nitrogen Pollutants

The discharge of urban sewage and agricultural non-point source pollutants is the main reason causing eutrophication in gullies in most cities of northern China. Based on a careful analysis on the ecological structure and ecological characteristics of a gully, this article preliminarily studies the interception and degradation mechanisms of nitrogen pollutants by the gully. Meanwhile, to take gullies in Changchun as the object of the study, this article carries out an experiment on the interception effect of nitrogen pollutants by gullies. This experiment respectively establishes a control section in the upper and lower reaches of a gully, and takes water samples four times in each section from May to August to determine total nitrogen, total phosphorus, nitrate nitrogen, ammonia nitrogen and salinity. The result shows: the gully plays some role in the interception of pollutants; total phosphorus accounts for the largest interception in pollutants in the experimented gully section, with the relative interception rate of 27.46%, followed by ammonia nitrogen, with the interception rate of 21.80%, which is the result of the combined effects of aquatic plants, microorganisms and sediment in the gully.

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Association of Snoring Characteristics with Predominant Site of Collapse of Upper Airway in Obstructive Sleep Apnoea Patients

SLEEP ◽

10.1093/sleep/zsab176 ◽

2021 ◽

Author(s):

Arun Sebastian ◽

Peter A Cistulli ◽

Gary Cohen ◽

Philip de Chazal

Keyword(s):

Acoustic Analysis ◽

Audio Signal ◽

Upper Airway ◽

Lateral Wall ◽

Sleep Apnoea ◽

Machine Learning Algorithms ◽

Classification Model ◽

Individual Site ◽

Obstructive Sleep ◽

The Individual

Abstract Study objectives Acoustic analysis of isolated events and snoring by previous researchers suggests a correlation between individual acoustic features and individual site of collapse events. In this study, we hypothesised that multi-parameter evaluation of snore sounds during natural sleep would provide a robust prediction of the predominant site of airway collapse. Methods The audio signals of 58 OSA patients were recorded simultaneously with full night polysomnography. The site of collapse was determined by manual analysis of the shape of the airflow signal during hypopnoea events and corresponding audio signal segments containing snore were manually extracted and processed. Machine learning algorithms were developed to automatically annotate the site of collapse of each hypopnoea event into three classes (lateral wall, palate and tongue-base). The predominant site of collapse for a sleep period was determined from the individual hypopnoea annotations and compared to the manually determined annotations. This was a retrospective study that used cross-validation to estimate performance. Results Cluster analysis showed that the data fits well in two clusters with a mean silhouette coefficient of 0.79 and an accuracy of 68% for classifying tongue/non-tongue collapse. A classification model using linear discriminants achieved an overall accuracy of 81% for discriminating tongue/non-tongue predominant site of collapse and accuracy of 64% for all site of collapse classes. Conclusions Our results reveal that the snore signal during hypopnoea can provide information regarding the predominant site of collapse in the upper airway. Therefore, the audio signal recorded during sleep could potentially be used as a new tool in identifying the predominant site of collapse and consequently improving the treatment selection and outcome.

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Online Fertilizer Recommendation System (OFRS): A Step Towards Precision Agriculture And Optimized Fertilizer Usage By Smallholder Farmers In Bangladesh

European Journal of Environment and Earth Sciences ◽

10.24018/ejgeo.2020.1.4.47 ◽

2020 ◽

Vol 1 (4) ◽

Author(s):

M. A. Hossain ◽

M. N. A. Siddique

Keyword(s):

Precision Agriculture ◽

Recommendation System ◽

Smallholder Farmers ◽

Fertilizer Application ◽

Soil Test ◽

Total Production ◽

Soil Database ◽

Fertilizer Recommendation ◽

Fertilizer Recommendations ◽

Input Cost

The recent progression and Green Revolution (approx. between the 1990s-2010s) in agriculture of Bangladesh resulted in an increase of total production despite yield-gap to ensure food security. But agriculture in Bangladesh is still backed-up by higher use of inputs (agrochemicals-fertilizers, pesticides; modern varieties, irrigation etc.) and inversion tillage. This conventional agrochemical-based smallholder agriculture may lead to soil and environmental degradation, soil acidification, and a decline in soil fertility. Therefore, it is significant to optimize input application in intensive agriculture, especially fertilizers. This paper introduces the potential online facilities of generating online fertilizer recommendations for smallholder farmers in Bangladesh to ensure proper usage of fertilizers and enable sustainable agricultural production. We also highlighted how the usage of fertilizers increased with an increase in total production over time. But the sustainability of production in the years to come still remain challenging. With the aim of sustainable crop production, reduction in the misuse of fertilizers and reduction of input cost by optimizing the present pattern of excessive fertilizer application, the Soil Resource Development Institute (SRDI) provides location-specific fertilizer recommendation through both the manual and soil test based interpretation of plant nutrients: soil database in Upzazila Nirdeshika and static laboratory soil analysis. Recently, SRDI developed web-based software named Online Fertilizer Recommendation System (OFRS). The system is capable of generating location-specific fertilizer recommendations for selected crops by analyzing the national soil database developed by this governmental institute. The software requires farmer field location, respective soil and land type, and crop type and variety information to generate crop-specific instant fertilizer recommendation. It was observed that by using fertilizer according to the recommended dose calculated on the basis of soil test values, farmers could harvest approx. 7-22% higher yield of different crops over usual farmers practice. If this system can be popularized and disseminated by effective agricultural extension, this would immensely contribute to the promotion of precision agriculture, input cost reduction and it would certainly enable us to optimize fertilizer application by the smallholder farmers in Bangladesh.

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Individual differences in the perception of probability

PLoS Computational Biology ◽

10.1371/journal.pcbi.1008871 ◽

2021 ◽

Vol 17 (4) ◽

pp. e1008871

Author(s):

Mel W. Khaw ◽

Luminita Stevens ◽

Michael Woodford

Keyword(s):

Extreme Values ◽

Full Range ◽

Response Speed ◽

Probability Estimation ◽

Behavioral Differences ◽

Extensive Experience ◽

Individual Level ◽

Pooled Data ◽

The Rich ◽

The Individual

In recent studies of humans estimating non-stationary probabilities, estimates appear to be unbiased on average, across the full range of probability values to be estimated. This finding is surprising given that experiments measuring probability estimation in other contexts have often identified conservatism: individuals tend to overestimate low probability events and underestimate high probability events. In other contexts, repulsive biases have also been documented, with individuals producing judgments that tend toward extreme values instead. Using extensive data from a probability estimation task that produces unbiased performance on average, we find substantial biases at the individual level; we document the coexistence of both conservative and repulsive biases in the same experimental context. Individual biases persist despite extensive experience with the task, and are also correlated with other behavioral differences, such as individual variation in response speed and adjustment rates. We conclude that the rich computational demands of our task give rise to a variety of behavioral patterns, and that the apparent unbiasedness of the pooled data is an artifact of the aggregation of heterogeneous biases.

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Diversity As A Unique Constellation of Superimposing Network Logics

Open House International ◽

10.1108/ohi-02-2012-b0002 ◽

2012 ◽

Vol 37 (2) ◽

pp. 6-14

Author(s):

Alain Thierstein ◽

Anne Wiese

Keyword(s):

Urban Space ◽

Urban Form ◽

Urban Life ◽

Industrial Sites ◽

Individual Site ◽

Scale Levels ◽

The One ◽

The Individual ◽

The City ◽

Underlying Processes

In the context of the European city, the regeneration of former industrial sites is a unique opportunity to actively steer urban development. These plots of land gain strategic importance in actively triggering development on the city scale. Ideally, these interventions radiate beyond the individual site and contribute to the strengthening of the location as a whole. International competition between locations is rising and prosperous development a precondition for wealth and wellbeing. This approach to the regeneration of inner city plots makes high demands on all those involved. Our framework suggests a stronger focus of the conceptualization and analysis of idiosyncratic resources, to enable innovative approaches in planning. On the one hand, we are discussing spatially restrained urban plots, which have the capacity and need to be reset. On the other hand, each plot is a knot in the web of relations on a multiplicity of scales. The material city is nested into a set of interrelated scale levels – the plot, the quarter, the city, the region, potentially even the polycentric megacity region. The immaterial relations however span a multicity of scale levels. The challenge is to combine these two perspectives for their mutual benefit. The underlying processes are constitutive to urban space diversity, as urban form shapes urban life and vice versa.

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