scholarly journals The ability of bumblebees Bombus terrestris (Hymenoptera: Apidae) to detect floral humidity is dependent upon environmental humidity

2021 ◽  
Author(s):  
Amy S. Harrison ◽  
Sean A. Rands
Keyword(s):  
Bombus Terrestris ◽  
Arid Environments ◽  
Environmental Humidity ◽  
Useful Signal ◽  
Insect Pollinators ◽  
Flower Type ◽  
Four Levels ◽  
Artificial Flowers ◽  
Communication Pathway ◽  
Different Levels

Flowers produce local humidity that is often greater than that of the surrounding environment, and studies have shown that insect pollinators may be able to use this humidity difference to locate and identify suitable flowers. However, environmental humidity is highly heterogeneous, and is likely to affect the detectability of floral humidity, potentially constraining the contexts in which it can be used as a salient communication pathway between plants and their pollinators. In this study, we use differential conditioning techniques on bumblebees Bombus terrestris audax (Harris) to explore the detectability of an elevated floral humidity signal when presented against different levels of environmental noise. Artificial flowers were constructed that could be either dry or humid, and individual bumblebees were presented with consistent rewards in either the humid or dry flowers presented in an environment with four levels of constant humidity, ranging from low (~20% RH) to highly saturated (~95% RH). Ability to learn was dependent upon both the rewarding flower type and the environment: the bumblebees were able to learn rewarding dry flowers in all environments, but their ability to learn humid rewarding flowers was dependent on the environmental humidity, and they were unable to learn humid rewarding flowers when the environment was highly saturated. This suggests that floral humidity might be masked from bumblebees in humid environments, suggesting that it may be a more useful signal to insect pollinators in arid environments.

scholarly journals Physical, chemical and microbiological properties of a Dystrophic Yellow Latosol using manipueira

2012 ◽  
Vol 32 (4) ◽  
pp. 736-744 ◽  
Author(s):  
João J. da Silva Júnior ◽  
Eugênio F. Coelho ◽  
José A. do V. Sant'Ana ◽  
Adriana M. de A. Accioly
Keyword(s):  
Particle Density ◽  
Biological Indicators ◽  
Soil Microbial ◽  
Dry Soil ◽  
Four Levels ◽  
Cassava Wastewater ◽  
Physical Changes ◽  
Different Levels ◽  
Soil Acid Phosphatase ◽  
Microbiological Properties

The study aimed to evaluate chemical, microbiological and hydro-physical changes of a Dystrophic Yellow Latosol, receiver of different levels of manipueira (cassava wastewater) application, in the cultivation of 'Terra Maranhão' banana. The experimental design was a randomized block with three replications in a factorial scheme 3 x 4, in which it was considered three soil depths and four levels of manipueira. It was evaluated the weighted mean diameter of the aggregate, the percentage of aggregation at different periods, soil density, particle density, porosity and soil saturated hydraulic conductivity, in addition to pH of P (mg dm -3), K (mg dm-3), Ca (cmolc dm-3), Mg (cmolc dm-3), Ca+Mg (cmolc dm-3), Al (cmolc dm-3), Na (cmolc dm -3), H+Al (cmolc dm-3), CEC (cmolc dm-3), V%, OM (g kg-1), soil microbial biomass (Ug Cg-1 dry soil), acid phosphatase (Ug PNP g-1 h-1). The use of manipueira influenced some physical characteristic of the soil, but it was not possible to specify the effect of increasing application dosage. Therefore, the application did not affect the biological indicators assessed in the soil or its pH. The use of manipueira as a fertilizer in the doses used in this study showed low increase of K, P, H+Al and Al in the soil and a good increase of Mg, Ca and Ca+Mg, Na, CEC and V%.

scholarly journals Different levels of shade on population of grasshoppers and its oviposition preference on heliconias

2018 ◽  
Vol 48 (2) ◽  
Author(s):  
Ana Cristina Bittar ◽  
Elen de Lima Aguiar-Menezes ◽  
José Guilherme Marinho Guerra ◽  
Janaína Ribeiro Costa Rouws ◽  
Luiz Augusto de Aguiar ◽  
...  
Keyword(s):  
Block Design ◽  
Oviposition Preference ◽  
Production Parameters ◽  
Lateral Buds ◽  
Randomized Block Design ◽  
Light Requirements ◽  
Four Levels ◽  
Preferred Species ◽  
Different Levels

ABSTRACT: Grasshoppers of the families Acrididae and Romaleidae (Orthoptera) are among the insects that defoliate heliconias and have been gaining status as pests of commercial crops of these plants in Brazil. The objectives of the present study were to identify the grasshopper defoliating heliconias in the municipality of Santo Antônio de Pádua, RJ (Brazil), to evaluate the effect of different levels of shade on the population of this grasshopper and the production parameters of heliconias, and to determine if this grasshopper has an oviposition preference among the heliconias evaluated. The experiment was in a completely randomized block design, in subdivided plots (four levels of shade in the plot, 0%, 30%, 50% and 80%, and four species of Heliconia: H. psittacorum, H. stricta, H. wagneriana and H. psittacorum x H. spathocircinata ‘Golden Torch’ in the subplot), with four replications. The grasshopper was identified as Cornops frenatum frenatum (Acrididae). An increase in shade resulted in a decrease in the number of oviposition holes from the grasshopper and the number of lateral buds. Shade did not influence the number of C. f. frenatum nymphs and adults and the number of flower stems. H. wagneriana was the most preferred species for oviposition by C. f. frenatum. Results suggested using screens to shade heliconia plants can help control C. f. frenatum populations, however, the light requirements of the heliconias should be considered to guarantee productivity.

scholarly journals The 4-Level Approach: Prevention of Suicidal Behaviour Through Community-Based Intervention

2021 ◽  
Vol 12 ◽  
Author(s):  
Ulrich Hegerl ◽  
Ines Heinz ◽  
Ainslie O'Connor ◽  
Hannah Reich
Keyword(s):  
Public Health ◽  
Primary Care ◽  
High Risk ◽  
Suicidal Behaviour ◽  
Lessons Learned ◽  
Community Based Interventions ◽  
Community Based ◽  
Four Levels ◽  
The Many ◽  
Different Levels

Due to the many different factors contributing to diagnostic and therapeutic deficits concerning depression and the risk of suicidal behaviour, community-based interventions combining different measures are considered the most efficient way to address these important areas of public health. The network of the European Alliance Against Depression has implemented in more than 120 regions within and outside of Europe community-based 4-level-interventions that combine activities at four levels: (i) primary care, (ii) general public, (iii) community facilitators and gatekeepers (e.g., police, journalists, caregivers, pharmacists, and teachers), and (iv) patients, individuals at high risk and their relatives. This review will discuss lessons learned from these broad implementation activities. These include targeting depression and suicidal behaviour within one approach; being simultaneously active on the four different levels; promoting bottom-up initiatives; and avoiding any cooperation with the pharmaceutical industry for reasons of credibility.

scholarly journals Intake, digestibility, and ruminal parameters of Nellore bulls supplemented with increasing levels of crude glycerin in Brachiaria Brizantha pastures

2017 ◽  
Vol 18 (4) ◽  
pp. 518-529 ◽  
Author(s):  
Adriano Jorge Possamai ◽  
Joanis Tilemahos Zervoudakis ◽  
Luciana Keiko Hatamoto-Zervoudakis ◽  
Lucien Bissi da Freiria ◽  
Pedro Ivo José Lopes da Rosa Silva ◽  
...  
Keyword(s):  
Organic Matter ◽  
Latin Square ◽  
Serum Glucose ◽  
Nutrient Digestibility ◽  
Crude Glycerin ◽  
Brachiaria Brizantha ◽  
Mineral Mixture ◽  
Organic Matter Digestibility ◽  
Four Levels ◽  
Different Levels

SUMMARY We evaluated the effects of increasing levels of crude glycerin in multiple supplements for grazing beef cattle on intake, nutrient digestibility, pH, ruminal ammoniacal nitrogen, and serum glucose. Five Nellore steers (initial BW of 480 kg [SD 15]), grazing a tropical pasture, were used in a 5 × 5 Latin square design. The treatments used were control (no supplementation; only a mineral mixture ad libitum) and four levels of crude glycerin (0, 80, 160, 240 g/kg of supplements). Supplementation type had no impact (P > 0.05) on pH at 0 and 4 h after supplementation. Animals supplemented with different levels of crude glycerin showed higher N-NH3 values (P < 0.05) at 4 h after supplementation. Crude glycerin supplementation did not reduce pasture intake (P > 0.05), increasing dry matter intake (P > 0.05) due to increased organic matter digestibility (P > 0.05). Supplementation of 4 kg/animal with crude glycerin (240 g/kg supplement) did not reduce pasture intake and organic matter digestibility.

Performance Testing of Segregated Hot-Mix Asphalt Samples to Evaluate Segregation Models

2005 ◽  
Vol 1907 (1) ◽  
pp. 118-127
Author(s):  
Junxia Wu ◽  
Pedro Romero
Keyword(s):  
Asphalt Concrete ◽  
High Performance ◽  
Performance Testing ◽  
Test Results ◽  
Constant Height ◽  
Frequency Sweep Test ◽  
Four Levels ◽  
Different Levels ◽  
Shear Tester ◽  
Light Medium

Testing of asphalt concrete samples was conducted by using the asphalt pavement analyzer test, the Superpave® shear tester (SST) frequency sweep test, and the SST repeat shear at constant height test to determine the rutting susceptibility that might be expected from samples that have different levels of segregation. Previous research had divided segregation into four levels: none, light, medium, and high. Test results suggest that samples with different segregation levels might show similar rutting susceptibility. Therefore, performance-related models were established in which segregation was divided into three levels: good, fair, and unacceptable. The performance-related models were applied to field data, and examination indicates that the modified models are capable of assessing segregation in field projects. Examination also found that fine segregation was present. Fine segregation can be predicted by extrapolating the developed model from the coarse part to the fine part. However, more data should be investigated to develop acceptable criteria for fine segregation. A methodology was developed to improve pavement quality by controlling aggregate segregation and poor compaction in placed mats. With the models and the proposed methodology, realistic construction uniformity could be assessed by agencies and contractors, which is the first step in obtaining pavements with high performance and longer service life.

scholarly journals Higher iridescent-to-pigment optical effect in flowers facilitates learning, memory and generalization in foraging bumblebees

2017 ◽  
Vol 284 (1865) ◽  
pp. 20171097 ◽  
Author(s):  
Géraud de Premorel ◽  
Martin Giurfa ◽  
Christine Andraud ◽  
Doris Gomez
Keyword(s):  
Bombus Terrestris ◽  
Optical Measurements ◽  
Long Term Memory ◽  
Memory Retention ◽  
Optical Effect ◽  
Plant Communication ◽  
Bona Fide ◽  
Angle Of View ◽  
Artificial Flowers

Iridescence—change of colour with changes in the angle of view or of illumination—is widespread in the living world, but its functions remain poorly understood. The presence of iridescence has been suggested in flowers where diffraction gratings generate iridescent colours. Such colours have been suggested to serve plant–pollinator communication. Here we tested whether a higher iridescence relative to corolla pigmentation would facilitate discrimination, learning and retention of iridescent visual targets. We conditioned bumblebees ( Bombus terrestris ) to discriminate iridescent from non-iridescent artificial flowers and we varied iridescence detectability by varying target iridescent relative to pigment optical effect. We show that bees rewarded on targets with higher iridescent relative to pigment effect required fewer choices to complete learning, showed faster generalization to novel targets exhibiting the same iridescence-to-pigment level and had better long-term memory retention. Along with optical measurements, behavioural results thus demonstrate that bees can learn iridescence-related cues as bona fide signals for flower reward. They also suggest that floral advertising may be shaped by competition between iridescence and corolla pigmentation, a fact that has important evolutionary implications for pollinators. Optical measurements narrow down the type of cues that bees may have used for learning. Beyond pollinator–plant communication, our experiments help understanding how receivers influence the evolution of iridescence signals generated by gratings.

The Van Hiele Levels of Geometric Thought in Undergraduate Preservice Teachers

1983 ◽  
Vol 14 (1) ◽  
pp. 58-69 ◽  
Author(s):  
Joanne Mayberry
Keyword(s):  
Preservice Teachers ◽  
Elementary Teachers ◽  
Van Hiele ◽  
High School Geometry ◽  
School Geometry ◽  
Geometric Concepts ◽  
Mathematics Educators ◽  
Four Levels ◽  
Scalogram Analysis ◽  
Different Levels

This study operationally defined and studied the five learning levels hypothesized by P. M. van Hiele and D. van Hiele-Geldof. Tasks were designed for the first four levels using seven common geometric concepts and revised after review by 11 mathematics educators. Audiotaped interviews were given to 19 preservice elementary teachers, 13 of whom had studied high school geometry. Guttman's scalogram analysis showed that the tasks representing the levels formed a hierarchy. A test of consensus revealed that students were on different levels for different concepts. Responses, in general, showed that the typical student in the study was not ready for a formal deductive geometry course.

ICT on four Levels of Inquiry-Based Science Education in Environmental Education

2013 ◽  
Vol 2 (1) ◽  
pp. 17-32
Author(s):  
Jana Přinosilová ◽  
Erika Mechlová ◽  
Svatava Kubicová
Keyword(s):  
Elementary School ◽  
Science Education ◽  
Environmental Education ◽  
Primary School ◽  
Learning Strategy ◽  
Natural Sciences ◽  
Four Levels ◽  
Different Levels ◽  
Selection Of

Abstract Inquiry in the natural sciences is an often used term. Inquiry-Based Science Education with the support of sophisticated ICT lacking. Inquiry-Based Science Education has clearly defined its four levels, in particular the use of teaching depends on the particular pupils and teachers. This learning strategy can thus rendering the various options and the use of ICT available at the school. The following article's focus is on a selection of specific technologies available and used at a primary school in connection with the different levels of Inquiry-Based Science Education and the extent of its involvement. The paper also describes social elaborated topic of environmental education in the sample worksheet for elementary school pupils.

scholarly journals Evaluation of Protein Concentration and Limiting Amino Acids Including Lysine and Met + Cys in Prestarter Diet on Performance of Broilers

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Mohsen Farkhoy ◽  
Mehrdad Modirsanei ◽  
Omid Ghavidel ◽  
Majid Sadegh ◽  
Sadegh Jafarnejad
Keyword(s):  
Amino Acids ◽  
Crude Protein ◽  
Protein Concentration ◽  
Optimal Level ◽  
Four Levels ◽  
Stage 1 ◽  
Dietary Treatments ◽  
Two Stages ◽  
Limiting Amino Acids ◽  
Different Levels

Four experiments were conducted, in two stages, to evaluate protein and limiting amino acids' (lysine and methionine + cystine) levels in pre-starter diets on broilers’ performance. In each experiment of Stage 1, 640 new-born male Ross 308 cockerels were randomly allocated to eight dietary treatments with a 2 × 4 factorial arrangement. In experiment 1-1, two levels of crude protein (CP: 21% and 23.2%) and four levels of Lys (1.2, 1.3, 1.4, and 1.5%) and in experiment 1-2, two levels of CP (21 and 23.2%) and four levels of Met + Cys (0.85, 0.90, 0.95, and 1.00%) were used. In Stage 2, the optimum levels of Lys and Met + Cys obtained from Stage 1 (1.3 and 1.5% Lys, 0.90 and 1.00% Met + Cys in experiment 1-1 and 1-2, resp.) with two levels of CP (21 and 23.2%) were used in two separate simultaneous experiments with a 2 × 2 factorial arrangement for male and female birds. The levels of CP significantly influenced BWG and FCR in experiment 1-1. Dietary levels of Lys affect BWG (experiment 1-1) and FI (experiments 1-1 and 2-1) significantly. In experiments 1-2 and 2-2, the different levels of Met + Cys did not affect BWG, FI, and FCR of male or female broilers. The results of these experiments indicated that the optimal level of dietary protein and Lys were 23.2% and 1.5%, respectively. Diets with 1% Met + Cys caused optimal performance.

Measurement of Trust in Humans in Hybrid Inspection for Different Levels of Error Randomness

2002 ◽  
Vol 46 (23) ◽  
pp. 1920-1924
Author(s):  
Neville Z. Ginwalla ◽  
Sittichai Kaewkuekool ◽  
Shannon R. Bowling ◽  
Anand K. Gramopadhye ◽  
Brian J. Melloy
Keyword(s):  
Experimental Designs ◽  
Inspection System ◽  
Four Levels ◽  
Inspection Tasks ◽  
Different Levels

The focus of this research is on the effect of human trust in a hybrid inspection system with different levels of error randomness. The experimental designs were developed to conduct inspection tasks with four levels of error randomness, and subjects were requested to rate their trust at different levels in the system. Each randomness level comprised of stages, and human trust variation for each stage was observed. These levels were administered through the use of a hybrid inspection simulator. Analysis of the results revealed that human trust in the hybrid inspection system is sensitive to error randomness.

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