scholarly journals Über Arthropodenabwehrstoffe, LXV. Die Chemische Ökologie des Grundschwimmers Laccophilus minutus / On Arthropode Defensive Compounds, LXV. The Chemical Ecology of the Water Beetle Laccophilus minutus

1983 ◽  
Vol 38 (12) ◽  
pp. 1678-1685 ◽  
Author(s):  
H. Schildknecht ◽  
B. Weber ◽  
K. Dettner
Keyword(s):  
Mass Spectrum ◽  
Chemical Ecology ◽  
The Other ◽  
Monophyletic Group ◽  
Pygidial Gland ◽  
Water Beetles ◽  
Water Beetle ◽  
Pygidial Gland Secretion ◽  
Defensive Glands ◽  
Main Component

According to a GC-MS analysis of methylated extracts the abdominal tips of the water beetle Laccophilus minutus (Dytiscidae) contain four β-hydroxyalkanoic acids. On the basis of MS and GC data another compound was assigned the structure of 6-octenoic acid.The same β-hydroxyalkanoic acids, and in addition, traces of β-hydroxyheptanoic acids were identified in dissected pygidial defensive glands after trimethylsilylation. Methyl 3,4-dihydroxyphenylacetate was recognized as a further main component in the pygidial gland secretion from the mass spectrum of its TMSi ether.The Laccophilinae occupy unique position among all the dytiscide subfamilies because they are the only water beetles which store β-hydroxyalkanoic acids in their pygidial glands. On the other hand the dytiscides appear to form a monophyletic group which is supported by the occurrence of methyl 3,4-dihydroxyphenylacetate. This class of compound is also commonly encountered in the other dytiscide subfamilies

scholarly journals The Diversity and Composition of Assemblages of Water Beetles (Gyrinidae, Dytiscidae, Hydrophilidae) in a Peat Bog in Belarus

Zoodiversity ◽  
2021 ◽  
Vol 55 (2) ◽  
pp. 113-120
Author(s):  
O. Shatarnova
Keyword(s):  
Species Composition ◽  
Diversity Index ◽  
Abundant Species ◽  
The Other ◽  
Peat Bog ◽  
Water Beetles ◽  
Water Beetle ◽  
Bog Lakes ◽  
Bog Water ◽  
High Diversity

The diversity and species composition of the water beetles in peat bog lakes, streams and hollows in Belarus were studied. In total, 45 species of water beetles belonging to 3 families (Gyrinidae, Dytiscidae, Hydrophilidae) were sampled by entomological net. Hydroporus tristis, Ilybius aenescens, Enochrus affinis, and E. ochropterus are the most abundant species A rather high diversity was recorded (Shannon-Wienner diversity index H′ = 2.037–2.912). Shannon-Wienner indexes indicated higher values in the lakes, whereas the lowest values in the hollows were recorded. In addition, in hollows water beetle species composition was the most different from the other peat bog water bodies.

Enhancing the Accuracy of Peak Hourly Demand in Bike-Sharing Systems using a Graph Convolutional Network with Public Transit Usage Data

2021 ◽  
pp. 036119812110120
Author(s):  
Jung-Hoon Cho ◽  
Seung Woo Ham ◽  
Dong-Kyu Kim
Keyword(s):  
Adjacency Matrix ◽  
Public Transit ◽  
Demand Forecasting ◽  
The Other ◽  
Convolutional Network ◽  
Demand Pattern ◽  
Temporal Features ◽  
Unmet Demand ◽  
Bike Sharing ◽  
Main Component

With the growth of the bike-sharing system, the problem of demand forecasting has become important to the bike-sharing system. This study aims to develop a novel prediction model that enhances the accuracy of the peak hourly demand. A spatiotemporal graph convolutional network (STGCN) is constructed to consider both the spatial and temporal features. One of the model’s essential steps is determining the main component of the adjacency matrix and the node feature matrix. To achieve this, 131 days of data from the bike-sharing system in Seoul are used and experiments conducted on the models with various adjacency matrices and node feature matrices, including public transit usage. The results indicate that the STGCN models reflecting the previous demand pattern to the adjacency matrix show outstanding performance in predicting demand compared with the other models. The results also show that the model that includes bus boarding and alighting records is more accurate than the model that contains subway records, inferring that buses have a greater connection to bike-sharing than the subway. The proposed STGCN with public transit data contributes to the alleviation of unmet demand by enhancing the accuracy in predicting peak demand.

Reassignment of Six Polyalthia Species to the New Genus Maasia (Annonaceae): Molecular and Morphological Congruence

2008 ◽  
Vol 33 (3) ◽  
pp. 490-494 ◽  
Author(s):  
Johan B. Mols ◽  
Paul J. A. Keßler ◽  
Steven H. Rogstad ◽  
Richard M. K. Saunders
Keyword(s):  
New Genus ◽  
Complex Form ◽  
The Other ◽  
Monophyletic Group ◽  
Bootstrap Support ◽  
Molecular Phylogenies

Recently published molecular phylogenies of the Annonaceae have confirmed the long-held hypothesis that the large paleotropical genus Polyalthia is polyphyletic. Species previously assigned to Polyalthia are now known to belong to up to six distinct, generally well-supported clades. Three members of a group of six species previously referred to as the Polyalthia hypoleuca complex form a monophyletic group (with 99% bootstrap support) that is only distantly related to the other species of Polyalthia sampled. Putative morphological synapomorphies are assessed, and justification provided for validating a new generic name, Maasia. Six species names in the Polyalthia hypoleuca complex are accordingly transferred to Maasia: M. discolor, M. glauca, M. hypoleuca, M. multinervis, M. ovalifolia, and M. sumatrana.

scholarly journals The Study Of Conversion Cpo To Polyol (Polyalcohol)

REAKTOR ◽  
2017 ◽  
Vol 11 (1) ◽  
pp. 8
Author(s):  
F. S. Budi ◽  
Z. Abidin
Keyword(s):  
Hydrogen Peroxide ◽  
Fatty Acid ◽  
Optimum Condition ◽  
Formic Acid ◽  
The Other ◽  
Hydroxyl Number ◽  
Main Component

Indonesia is the second big CPO producer after Malaysia. The CPO production of Indonesia gradually increases and reaches 8.2 million tones. About two third of it is used to meet the domestic will receive little income. Therefore, it must be converted into the other product, which has the high value. The main component of it is glyceride composed of glycerol  and fatty acid. The glyceride can be converted into polyol (polyalcohol) which is the material in manufacturing polyurethane, cosmetic, lubricant etc. the process of converting of CPO into polyol is called  the hydroxylation. This research aim to study the hydroxylation process of CPO into polyol and to optimize the variable which really affect the hydroxyl number of product. Based on the experiment, the optimum condition of hydroxylation of CPO with the hydrogen peroxide (H2O2) and the formic acid (HCOOH) into polyol is got as follows: temperature 50 0C, composition of reactan 40% and time 2 hours. The polyol produced has the hydroxyl number 148.Keywords : CPO, hydroxylation, polyol

Description of Leptoomus janzeni, n. gen. and n. sp. (Hymenoptera: Chalcidoidea) from Baltic amber, and discussion of its relationships and classification relative to Eupelmidae, Tanaostigmatidae and Encyrtidae

Zootaxa ◽  
2008 ◽  
Vol 1730 (1) ◽  
pp. 1 ◽  
Author(s):  
GARY A. P. GIBSON
Keyword(s):  
Sister Group ◽  
Structural Features ◽  
Sensu Stricto ◽  
The Other ◽  
Monophyletic Group ◽  
Baltic Amber ◽  
Unique Combination ◽  
Relative Structure

Leptoomus janzeni, n. gen. and n. sp., is described from 5 females and 2 males in 7 pieces of Baltic amber. An enlarged acropleuron forming the entire mesopleuron places the taxon within Eupelmidae, Tanaostigmatidae or Encyrtidae (Chalcidoidea), but it has a unique combination of features that differentiates it from extant members of these families. Its structural features are compared with those that characterize the three families and it is postulated to be the sister group of Tanaostigmatidae sensu stricto + (Cynipencyrtus + Encyrtidae) based on relative structure of its pronotum, prepectus and mesothoracic spiracle, and retention of two other putative symplesiomorphies, the presence of complete furrowlike notauli and a protibial apical spicule. Conflicting character states indicate other possible relationships, including a sistergroup relationship with Cynipencyrtus + Encyrtidae based on transverse-triangular axillae and a flagellum having only seven funicular segments, or with Tanaostigmatidae s. s. based on presence of an externally visible prepectal pouch, or possibly forming a monophyletic group with Tanaostigmatidae s. s. + Cynipencyrtus based on combined acropleuralmetacoxal structure. Several features support the monophyly of Tanaostigmatidae s. s., that is excluding Cynipencyrtus and Leptoomus, but these two genera are both classified in Tanaostigmatidae sensu lato until relationships are resolved more conclusively. Features possessed by different members of Neanastatinae (Eupelmidae) suggest that this subfamily may be closely related to Tanaostigmatidae s. l. + Encyrtidae, but possible relationships of Tanaostigmatidae s. s. are also discussed if its enlarged acropleuron and other skeletomusculature features associated with jumping are convergent to similar features in the other taxa.

THE COLEOPTERA OF CANADA

1895 ◽  
Vol 27 (7) ◽  
pp. 181-186 ◽  
Author(s):  
H. F. Wickham
Keyword(s):  
The Other ◽  
Water Beetles ◽  
Generalized Type ◽  
General Appearance

XI. The Hydrophilidæ of Ontario and Quebec.These water-beetles differ from Dytiscidæ especially in having the antennæ terminated by a distinct club instead of being filiform; and while, as the name implies, they are usually found in ponds or streams, they are much more feeble swimmers than the Dytiscids, and are exponents of a more generalized type. Several genera are truly terrestrial in habit, the beetles occurring about decomposing animal matter or in manure. The larvæ somewhat resemble those of the Dytiscidæ in general appearance, but differ so far as my experience goes in having toothed mandibles instead of the single suctorial ones characteristic of the other family. Pupation takes place on land in an underground cell, or in a cavity scooped out beneath a stone or piece of wood.

AN ELECTRON IMPACT STUDY OF SOME C8HI0 ISOMERS

1965 ◽  
Vol 43 (1) ◽  
pp. 211-218 ◽  
Author(s):  
F. Meyer ◽  
P. Haynes ◽  
Stewart McLean ◽  
A. G. Harrison
Keyword(s):  
Mass Spectrum ◽  
Electron Impact ◽  
Mass Spectra ◽  
Major Part ◽  
The Other ◽  
Fragmentation Pattern ◽  
Impact Study ◽  
Deuterium Labelling ◽  
Appearance Potential ◽  
Alkyl Benzenes

The mass spectra of 1-, 2-, and 6-methylspiro[2.4]hepta-1,3-diene have been measured and found to be very similar to the spectra of 7-methylcycloheptatriene and the isomeric alkyl benzenes. It is concluded that in all cases the major part of the fragmentation occurs by identical paths involving identical intermediates. This conclusion is supported by deuterium labelling and appearance potential data. On the other hand the mass spectrum of 2,5-dimethyl-1,5-hexadien-3-yne, an acyclic C8H10 isomer, shows a number of significant differences in its fragmentation pattern. These differences are reflected in the energetics of ion formation and it is concluded that in this case the fragmentation proceeds through different intermediates.

scholarly journals Multivariate analysis of strawberry experiments: where are we now and where can we go?

2021 ◽  
Author(s):  
Tiago Olivoto ◽  
Maria Inês Diel ◽  
Denise Schmidt ◽  
Alessandro Dal’Col Lúcio
Keyword(s):  
Multivariate Analysis ◽  
Rice Husk ◽  
Organic Substrate ◽  
The Other ◽  
Soluble Solids ◽  
Organic Substrates ◽  
Water Efficiency ◽  
Multiple Traits ◽  
Main Component ◽  
Short Days

ABSTRACTThe multi-trait genotype-ideotype distance index (MGIDI) was used to select superior treatments in experiments with strawberries. Twenty-three productive, qualitative, physiological, and phenological traits with negative and positive desired gains were accessed in 16 treatments, a combination of two cultivars (Albion-neutral days, and Camarosa-short days), two transplants origins (National and Imported), and four organic substrates mixes (Crushed sugarcane bagasse, burnt rice husk, organic substrate, and Carolina commercial substrate). Our results suggest that most of the strawberry traits are influenced by the cultivar, transplant origin, cultivation substrates, as well as by the interaction between cultivar and transplant origin. The MGIDI index indicated that the Albion cultivar originated from imported transplants grown in substrates where the main component (70%) is burnt rice husk provides desired values for 20 of a total of 22 traits, which represents a success rate of ~ 91% in selecting traits with desired values. The strengths and weakness view provided by the MGIDI index revealed that the looking for an ideal treatment should direct the efforts on improving the water efficiency use and reducing total acidy of fruits. On the other hand, the strengths of selected treatments are mainly related to productive precocity, total soluble solids, and flesh firmness. The MGIDI index provides a unique, robust, and easy-to-handle process, standing out as a powerful tool to develop better treatment recommendations for experiments with strawberries when multiple traits are assessed.

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