8,379 research outputs found
Allocation of Authority in Agricultural Production Contracts
The objective of this paper is to develop a model that explains the involvement of first level handlers in farm level decisions. In particular, the research attempts to explain observed differences among levels of farmer's autonomy in production contracts of different agricultural commodities. We show that the trade off that a contractor faces for holding the decision rights for controlling production inputs varies for different production environments. In particular, the contractor prefers controlling inputs in production of commodities that have relatively uniform production environments, whereas it is more efficient to delegate the control to the producer for commodities that have diverse production environments.Agribusiness,
Effects of in-office bleaching agent combined with different desensitizing agents on enamel
Objective: To analyze color change, microhardness and chemical composition of enamel bleached with in-office bleaching agent with different desensitizing application protocols. Materials and Methods: One hundred and seventeen polished anterior human enamel surfaces were obtained and randomly divided into nine groups (n=13). After recording initial color, microhardness and chemical composition, the bleaching treatments were performed as G1: Signal Professional White Now POWDER&LIQUID FAST 38% Hydrogen peroxide(S); G2: S+Flor Opal/0.5% fluoride ion(F); G3: S+GC Tooth Mousse/Casein Phosphopeptide-Amorphous Calcium Phosphate (CPPACP) paste(TM); G4: S+UltraEZ/3% potassium nitrate&0.11% fluoride(U); G5: S+Signal Professional SENSITIVE PHASE 1/30% Nano-Hydroxyapatite (n-HAP) suspension(SP); G6: S-F mixture; G7: S-TM mixture; G8: S-U mixture; G9: S-SP mixture. Color, microhardness and chemical composition measurements were repeated after 1 and 14 days. The percentage of microhardness loss (PML) was calculated 1 and 14 days after bleaching. Data were analyzed with ANOVA, Welch ANOVA, Tukey and Dunnett T3 tests (p<0.05). Results: Color change was observed in all groups. The highest ΔE was observed at G7 after 1 day, and ΔE at G8 was the highest after 14 days (p<0.05). A decrease in microhardness was observed in all groups except G6 and G7 after 1 day. The microhardness of all groups increased after 14 days in comparison with 1 day after bleaching (p>0.05). PML was observed in all groups except G6 and G7 after bleaching and none of the groups showed PML after 14 days. No significant changes were observed after bleaching at Ca and P levels and Ca/P ratios at 1 or 14 days after bleaching (p>0.05). F mass increased only in G2 and G6, 1 day after bleaching (p<0.05). Conclusions: The use of desensitizing agents containing fluoride, CPP-ACP, potassium nitrate or n-HAP after in-office bleaching or mixed in bleaching agent did not inhibit the bleaching effect. However, they all recovered microhardness of enamel 14 days after in-office bleaching
Down Type Isosinglet Quarks in ATLAS
We evaluate the discovery reach of the ATLAS experiment for down type
isosinglet quarks, , using both their neutral and charged decay channels,
namely the process with subsequent decays resulting in
, and final states.
The integrated luminosity required for observation of a heavy quark is
estimated for a mass range between 600 and 1000 GeV using the combination of
results from different search channels.Comment: 12 page
Skin Lesion Analyser: An Efficient Seven-Way Multi-Class Skin Cancer Classification Using MobileNet
Skin cancer, a major form of cancer, is a critical public health problem with
123,000 newly diagnosed melanoma cases and between 2 and 3 million non-melanoma
cases worldwide each year. The leading cause of skin cancer is high exposure of
skin cells to UV radiation, which can damage the DNA inside skin cells leading
to uncontrolled growth of skin cells. Skin cancer is primarily diagnosed
visually employing clinical screening, a biopsy, dermoscopic analysis, and
histopathological examination. It has been demonstrated that the dermoscopic
analysis in the hands of inexperienced dermatologists may cause a reduction in
diagnostic accuracy. Early detection and screening of skin cancer have the
potential to reduce mortality and morbidity. Previous studies have shown Deep
Learning ability to perform better than human experts in several visual
recognition tasks. In this paper, we propose an efficient seven-way automated
multi-class skin cancer classification system having performance comparable
with expert dermatologists. We used a pretrained MobileNet model to train over
HAM10000 dataset using transfer learning. The model classifies skin lesion
image with a categorical accuracy of 83.1 percent, top2 accuracy of 91.36
percent and top3 accuracy of 95.34 percent. The weighted average of precision,
recall, and f1-score were found to be 0.89, 0.83, and 0.83 respectively. The
model has been deployed as a web application for public use at
(https://saketchaturvedi.github.io). This fast, expansible method holds the
potential for substantial clinical impact, including broadening the scope of
primary care practice and augmenting clinical decision-making for dermatology
specialists.Comment: This is a pre-copyedited version of a contribution published in
Advances in Intelligent Systems and Computing, Hassanien A., Bhatnagar R.,
Darwish A. (eds) published by Chaturvedi S.S., Gupta K., Prasad P.S. The
definitive authentication version is available online via
https://doi.org/10.1007/978-981-15-3383-9_1
Effect of nano and micro-silica on bond behaviour of steel and polypropylene fibres in high volume fly ash mortar
This paper presents the effects of nano silica (NS), micro silica (MS) and combined NS and MS on bond behaviour of steel and polypropylene (PP) fibres in high volume fly ash (HVFA) mortar. Three types of bend configuration of hook-end steel fibre commercially available are considered, while the PP fibre was crimped shape. Three different fly ash contents of 40%, 50% and 60% (by wt) as partial replacement of ordinary Portland cement (OPC) are considered in HVFA mortar, while a control mortar containing 100% OPC was also considered. The NS and the MS was added as 2% and 10% (by wt), respectively as partial replacement of OPC in HVFA mortar containing 40% fly ash. In the case of combined NS and MS, 2% NS and 10% MS was used as partial replacement of OPC in HVFA mortar. However, in the case of HVFA mortars containing 40% fly ash and different NS and MS, total OPC content of 60% was kept constant in all HVFA mixes containing NS, MS and NS + MS. This was considered to compare these mixes with HVFA mortar containing 40% fly ash. Results indicate that maximum pull-out force of both steel and PP fibres decreases with increase in fly ash contents in HVFA mortars at both 7 and 28 days.The addition of 2% NS and 10% MS showed almost similar improvement in the maximum pull-out force of steel and PP fibres at both ages in HVFA mortar containing 40% fly ash. The combined use of 2%NS + 10%MS also improved the maximum pull-out force and higher than 2% NS and 10% MS. The reduction in large capillary pores in HVFA mortars containing nano and micro silica observed in Mercury Intrusion Porosity test improved the bond of steel and PP fibres in those mortar due to formation of additional calcium silicate hydrate (C-S-H) gel is believed to be the reason behind this improvement. The maximum pull-out force also increased with increase in number of bends in the hook-end of steel fibre in all mortars in this study at both 7 and 28 days. Extra energy absorbed by the higher number of bends is the reason of such improvement in maximum pull-out force. However, in the case of absorbed energy mixed results are observed in the case of different number of bends in steel fibre ends. Good correlations also exist between the maximum pull-out forces of all three types of steel fibres with compressive strength of mortars showing strong influence on the bond behaviour
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