Bumblebee foraging and floral scent dimorphism: Bombus kirbyellus Curtis (Hymenoptera: Apidae) and Polemonium viscosum Nutt. (Polemoniaceae)

1983 ◽  
Vol 61 (6) ◽  
pp. 1207-1213 ◽  
Author(s):  
Candace Galen ◽  
Peter G. Kevan
Keyword(s):  
Standing Crop ◽  
Sucrose Solution ◽  
Floral Scent ◽  
Nearest Neighbors ◽  
Field Observations ◽  
Initial Visit ◽  
Floral Visitation ◽  
Experimental Trials ◽  
The Relationship ◽  
Preference Tests

Plants of Polemonium viscosum have either sweet- or skunky-scented flowers. In this paper we examine the relationship between floral scent and visitation by the principal pollinator, Bombus kirbyellus. Field observations of nectar collecting bumblebee queens showed that bees visited plants with sweet-scented flowers significantly more often than those with skunky scent and tended to visit more flowers per inflorescence of sweet than of skunky scent. These observations agree with results from preference tests with captive bees foraging under controlled conditions on enclosed arrays of the two scent morphs. In experimental trials, bee orientation on the initial visit to the array and on visits between plants within the array favored sweet-scented inflorescences. Bees moved on the grid in such a way that skunky-scented nearest neighbors were undervisited, while sweet-scented flowers were visited more often than expected. In one set of trials, sucrose solution was added to flowers in order to compensate for natural standing crop variation. This treatment did not reduce bumblebee preference for the sweet scent morph nor alter the movement patterns of bees on the grid. Hence, in this system, floral visitation pattern appears to be influenced more strongly by scent than by nectar level.

Sucrose Preference as a Function of Water Deprivation and Prepreference Training

1979 ◽  
Vol 45 (3) ◽  
pp. 823-827 ◽  
Author(s):  
Jerome S. Cohen ◽  
Brian Burtt
Keyword(s):  
Water Deprivation ◽  
Sucrose Solution ◽  
Forced Choice ◽  
Sucrose Preference ◽  
Relationship Of ◽  
The Relationship ◽  
Preference Tests

Highly (23.5-hr.) as well as moderately (18-hr.) water-deprived animals preferred a location containing a 10% sucrose solution to one containing water after experiencing a series of forced-choice trials to each reward. Reliable incentive preferences were either eliminated or their development considerably retarded in highly water-deprived animals, however, when they experienced only sucrose at both positions prior to preference tests. These findings help explain discrepant results on the relationship of drive and incentive choice previously obtained in our laboratory from those in Beck's laboratory.

scholarly journals Richness of Rhizosphere Organisms Affects Plant P Nutrition According to P Source and Mobility

Agriculture ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 157
Author(s):  
Jean Trap ◽  
Patricia Mahafaka Ranoarisoa ◽  
Usman Irshad ◽  
Claude Plassard
Keyword(s):  
Careful Consideration ◽  
Soil Conditions ◽  
Organic P ◽  
P Nutrition ◽  
Soil P ◽  
P Acquisition ◽  
Complex Interactions ◽  
Experimental Trials ◽  
The Relationship

Plants evolve complex interactions with diverse soil mutualist organisms to enhance P mobilization from the soil. These strategies are particularly important when P is poorly available. It is still unclear how the soil P source (e.g., mineral P versus recalcitrant organic P) and its mobility in the soil (high or low) affect soil mutualist biological (ectomycorrhizal fungi, bacteria and bacterial-feeding nematodes) richness—plant P acquisition relationships. Using a set of six microcosm experiments conducted in growth chamber across contrasting P situations, we tested the hypothesis that the relationship between the increasing addition of soil mutualist organisms in the rhizosphere of the plant and plant P acquisition depends on P source and mobility. The highest correlation (R2 = 0.70) between plant P acquisition with soil rhizosphere biological richness was found in a high P-sorbing soil amended with an organic P source. In the five other situations, the relationships became significant either in soil conditions, with or without mineral P addition, or when the P source was supplied as organic P in the absence of soil, although with a low correlation coefficient (0.09 < R2 < 0.15). We thus encourage the systematic and careful consideration of the form and mobility of P in the experimental trials that aim to assess the role of biological complexity on plant P nutrition.

scholarly journals Collaborative filtering recommendation algorithm based on user correlation and evolutionary clustering

2019 ◽  
Vol 6 (1) ◽  
pp. 147-156 ◽  
Author(s):  
Jianrui Chen ◽  
Chunxia Zhao ◽  
Uliji ◽  
Lifang Chen
Keyword(s):  
Dimension Reduction ◽  
Collaborative Filtering ◽  
Data Clustering ◽  
Real Life ◽  
Nearest Neighbors ◽  
User Group ◽  
Recommendation Algorithm ◽  
Evolutionary Clustering ◽  
The Relationship ◽  
Score Matrix

Abstract In recent years, application of recommendation algorithm in real life such as Amazon, Taobao is getting universal, but it is not perfect yet. A few problems need to be solved such as sparse data and low recommended accuracy. Collaborative filtering is a mature algorithm in the recommended systems, but there are still some problems. In this paper, a novel collaborative filtering recommendation algorithm based on user correlation and evolutionary clustering is presented. Firstly, score matrix is pre-processed with normalization and dimension reduction, to obtain denser score data. Based on these processed data, clustering principle is generated and dynamic evolutionary clustering is implemented. Secondly, the search for the nearest neighbors with highest similar interest is considered. A measurement about the relationship between users is proposed, called user correlation, which applies the satisfaction of users and the potential information. In each user group, user correlation is applied to choose the nearest neighbors to predict ratings. The proposed method is evaluated using the Movielens dataset. Diversity experimental results demonstrate that the proposed method has outstanding performance in predicted accuracy and recommended precision.

Species richness – standing crop relationships along four lakeshore gradients: constraints on the general model

1989 ◽  
Vol 67 (6) ◽  
pp. 1609-1617 ◽  
Author(s):  
Irene C. Wisheu ◽  
Paul A. Keddy
Keyword(s):  
Species Richness ◽  
Nova Scotia ◽  
Soil Fertility ◽  
General Model ◽  
Standing Crop ◽  
Clay Content ◽  
Lower Proportion ◽  
Loss On Ignition ◽  
Habitat Variation ◽  
The Relationship

The applicability of a model describing the relationship between species richness and standing crop and litter was tested in each of four lakeshore habitats within Wilsons Lake, Nova Scotia. The shapes of the curves describing the species richness – standing crop relationships in the four habitats were significantly different. Standing crop and litter values were positively correlated with measured indices of soil fertility (loss on ignition and silt and clay content) and negatively correlated with disturbance as determined by the location of the shrub zone and overwinter damage to wooden pegs. Sites with high standing crop had a lower proportion of biomass composed of evergreen and isoetid species than the proportion in sites where standing crop was low. The among habitat variation observed in this study, and the variation in published values of standing crop values yielding maximum species richness, limit the accuracy of predictions from this model. Steps for refinement are suggested.

Seston supply to sea scallops (Placopecten magellanicus) in suspended culture

2001 ◽  
Vol 58 (2) ◽  
pp. 241-253 ◽  
Author(s):  
C A Pilditch ◽  
J Grant ◽  
K R Bryan
Keyword(s):  
Carrying Capacity ◽  
Field Data ◽  
Field Observations ◽  
Placopecten Magellanicus ◽  
Factors Affecting ◽  
Advection Diffusion ◽  
Tidally Driven ◽  
Sea Scallops ◽  
Minimal Reduction ◽  
The Relationship

The filtration activity of dense aggregations of bivalves can locally reduce the concentration of seston, potentially limiting production. Under these conditions, the currents that supply seston cannot offset ingestion by the bivalves and the carrying capacity is exceeded. We conducted a field and modelling study to examine factors affecting seston supply to a culture of suspended sea scallops (Placopecten magellanicus) in Whitehaven Harbour, Nova Scotia. Even though seston flux to the scallops was reduced by 40% due to the attenuation of flow by culture gear, a reduction in seston concentration was not observed. The field data were then used to parameterize a quasi two-dimensional advection-diffusion model that quantified the relationship between the tidally driven seston supply and consumption by scallops. The model predicted a minimal reduction in seston concentration (<5%) within the lease (80 × 50 m), consistent with field observations. However, expanding the lease to occupy the area available for cultivation (1000 × 250 m) reduced the seston concentration in the centre of the lease by 20-50%, potentially limiting growth. Modelling results emphasized that by altering the lease geometry (lease width to length ratio), the supply of seston can be optimized.

scholarly journals Hubungan Tingkat Partisipasi dengan Tingkat Kesejahteraan Masyarakat dalam Pengembangan Wisata Pesisir

2020 ◽  
Vol 12 (2) ◽  
pp. 68
Author(s):  
Annisya Rakha Anandhyta ◽  
Rilus A. Kinseng
Keyword(s):  
Local Governments ◽  
Quantitative Data ◽  
Qualitative Data ◽  
Coastal Region ◽  
Cluster Method ◽  
Field Observations ◽  
Beach Tourism ◽  
The Relationship ◽  
Depth Interviews ◽  
New Jobs

Abstrak Berdasarkan UU No. 10 Tahun 2009 tentang Kepariwisataan, Pariwisata adalah macam-macam kegiatan wisata dan didukung berbagai fasilitas serta layanan yang disediakan oleh masyarakat, pengusaha, pemerintah, dan pemerintah daerah. Salah satu kawasan pariwisata yang dimiliki Indonesia adalah wilayah pesisir. Pengembangan kawasan wisata dapat dilakukan melalui partisipasi aktif masyarakat dalam rangka menciptakan lapangan pekerjaan baru dan menyejahterakan masyarakat.  Penelitian ini bertujuan untuk melihat hubungan antara tingkat partisipasi dengan tingkat kesejahteraan anggota Pokdarwis Baron Indah dalam pengembangan kawasan wisata Pantai Baron. Metode yang digunakan adalah pendekatan kuantitatif yang didukung oleh data kualitatif. Data kuantitatif diperoleh melalui kuesioner dan data kualitatif diperoleh melalui wawancara mendalam menggunakan panduan wawancara serta observasi lapang. Teknik dalam penentuan responden penelitian menggunakan cluster accidental sampling. Hasil penelitian menunjukkan bahwa sebagian besar anggota Pokdarwis Baron Indah berada pada tingkat partisipasi sedang. Penelitian ini juga menunjukkan adanya hubungan positif yang signifikan antara tingkat partisipasi dengan tingkat kesejahteraan. AbstractBased on Law No. 10 of 2009 concerning tourism, tourism is defined as a variety of tourism activities and supported by various facilities and services provided by the community, entrepreneurs, government, and local governments. One of the tourism areas that Indonesia has is a coastal region. The development of tourism areas can be done through active community participation in order to create new jobs and improve the welfare of the community. This study aims to investigate the relationship between the level of participation with the level of welfare of members of Pokdarwis Baron Indah in the development of the Baron Beach tourism area. The method used is a quantitative approach and supported by qualitative data. Quantitative data obtained through questionnaires and qualitative data obtained through in-depth interviews using interview guides and field observations. Respondents were selected by “accidental sampling cluster” method. The results showed that the level of participation of most of the Pokdarwis Baron Indah members fall within the medium category. This study also shows that the level of participation and the level of welfare of Pokdarwis members are positively and significantly correlated.

scholarly journals Synergy of Parents and Teachers in Students Learning to Instill Religious and Moral Values in the Pandemic Period

2021 ◽  
Vol 18 (1) ◽  
pp. 21-36
Author(s):  
Erni Munastiwi
Keyword(s):  
Qualitative Method ◽  
Research Result ◽  
Research Data ◽  
Field Observations ◽  
Education Services ◽  
Home Learning ◽  
Data Validity ◽  
Teachers And Parents ◽  
Relationship Of ◽  
The Relationship

The relationship of parents and teachers in the education unit has an important role in optimizing students' abilities. But the outbreak of the covid-19 pandemic has an impact on education services. Therefore, this study aims to determine tips on the optimization of teachers and parents in the religious and moral aspects of the children during home learning. This research employed a descriptive qualitative method at RA Ar-Rafif Kalasan Yogyakarta (n=15). The data sources of this study are teachers, principals, and parents. Research data were collected through field observations, interviews with teachers and parents, and documentation in form of photos/videos and captures of conversation between teachers and parents. The data validity is tested by using triangulation techniques. The data analysis is acquired by reducing the data that has been collected, presenting the data, and providing conclusions of the research results. The research result shows that synergy of parents and teachers can optimize children’s development aspects of religion and moral obtained through various programs and activities designed by the educators.

scholarly journals Influence of Mealiness on the Firmness of Apples after Harvest

HortScience ◽  
2005 ◽  
Vol 40 (7) ◽  
pp. 2091-2095 ◽  
Author(s):  
Hiroshi Iwanami ◽  
Shigeki Moriya ◽  
Nobuhiro Kotoda ◽  
Sae Takahashi ◽  
Kazuyuki Abe
Keyword(s):  
Relative Humidity ◽  
Cell Separation ◽  
Sucrose Solution ◽  
Storage Conditions ◽  
Flesh Firmness ◽  
The Relationship

Changes in flesh firmness and mealiness during storage were investigated in 24 apple [Malus ×sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.] cultivars and selections (genotypes) up to 40 days after harvest under 20 ± 2 °C and 85% ± 5% relative humidity storage conditions. Flesh firmness was measured using a penetrometer, while mealiness was quantified by measuring the degree of cell separation in tissue induced by shaking discs of tissue in a sucrose solution. According to the relationship between the change in firmness and mealiness, the genotypes can be divided into four groups: those that did not soften and remained hard and nonmealy during storage; those that softened without mealiness; those that softened with slight mealiness; and those that softened with mealiness. Firmness decreased below 30 N in fruit that softened with mealiness, and the minimum firmness during storage was correlated with the degree of mealiness at 30 days of storage. The rate of softening was the highest in fruit that softened with mealiness. Therefore, it was concluded that, by measuring the firmness and changes in firmness that take place during storage, the genotypes resulting in softening with mealiness and those that result in softening without mealiness could be identified.

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