scholarly journals A Chemotaxonomic Study of Cuticular Hydrocarbons on Epilachna indica (Family: Coccinellidae) from Sarawak

1970 ◽  
Vol 4 (1) ◽  
pp. 9-18
Author(s):  
Rizoh Bosorang ◽  
Zaini Assim ◽  
Sulaiman Hanapi
Keyword(s):  
Cuticular Hydrocarbons ◽  
Cross Validation ◽  
Function Analysis ◽  
Cuticular Hydrocarbon ◽  
Hydrocarbon Composition ◽  
Ladybird Beetles ◽  
Significant Difference ◽  
Peak Areas ◽  
Chemotaxonomic Study ◽  
Chain Lengths

The chemical composition of cuticular hydrocarbons of adult Epilacnha indica (ladybird beetles), collected fromKota Samarahan, Kota Padawan and Lanjak-Entimau, Sarawak were analyzed by using a capillary gaschromatography-mass spectrometer (GC-MS). Cuticular hydrocarbons extracted from 18 samples of adult E.indica (comprise of 90 individuals). Over 95% of the hydrocarbon peak areas consist of chain lengths from C18to C38 . The proportions of n-alkanes between three different localities are significantly difference, except for ndotriacontaneand n-tetratriacontane. Comparison between Kota Samarahan and Kota Padawan samples revealedthe significant different in hydrocarbon composition for even-numbered carbon n-alkanes ranging from n-C18 ton-C38 except for n-C32 and n-C34 . Several odd-numbered carbon n-alkanes such as n-C25 , n-C27 , n-C33 and n-C35 also showed significant difference in the composition between Kota Samarahan and Kota Padawan.Examination on components contributing to the differentiation of localities showed that n-C29 , n-C33 and n-C36were important in discriminating three different localities. Discriminant function analysis (DFA) successfullyclassified all samples into three correct groups in 100% of cases, with cross-validation resulted in an error of7.7%. Individuals from each locality were grouped in the range of 2.10 - 9.16% differences, with average of43% different reflected between localities. E. indica samples collected from the forests containing simplerhydrocarbon pattern than samples collected around housing or industrial areas. Result showed that differences inmicroenvironment have influenced the composition and proportion of insect cuticular hydrocarbon. The findingreveals the potential of cuticular hydrocarbons profile to separate subpopulations of species.

scholarly journals Cuticular hydrocarbons discriminate cryptic Macrolophus species (Hemiptera: Miridae)

2012 ◽  
Vol 102 (6) ◽  
pp. 624-631 ◽  
Author(s):  
C. Gemeno ◽  
N. Laserna ◽  
M. Riba ◽  
J. Valls ◽  
C. Castañé ◽  
...  
Keyword(s):  
Biological Control ◽  
Cuticular Hydrocarbons ◽  
Cross Validation ◽  
Molecular Genetic ◽  
Cuticular Hydrocarbon ◽  
Hydrocarbon Composition ◽  
Dark Spot ◽  
Prediction Errors ◽  
Control Activity ◽  
Genetic Studies

AbstractMacrolophus pygmaeus is commercially employed in the biological control of greenhouse and field vegetable pests. It is morphologically undistinguishable from the cryptic species M. melanotoma, and this interferes with the evaluation of the biological control activity of M. pygmaeus. We analysed the potential of cuticular hydrocarbon composition as a method to discriminate the two Macrolophus species. A third species, M. costalis, which is different from the other two species by having a dark spot at the tip of the scutellum, served as a control. Sex, diet and species, all had significant effects in the cuticular hydrocarbon profiles, but the variability associated to sex or diet was smaller than among species. Discriminant quadratic analysis of cuticular hydrocarbons confirmed the results of previous molecular genetic studies and showed, using cross-validation methods, that M. pygmaeus can be discriminated from M. costalis and M. melanotoma with prediction errors of 6.75% and 0%, respectively. Therefore, cuticular hydrocarbons can be used to separate M. pygmaeus from M. melanotoma reliably.

CUTICULAR HYDROCARBON ANALYSIS OF THE AQUATIC BEETLE AGABUS ANTHRACINUS MANNERHEIM (COLEOPTERA: DYTISCIDAE)

1998 ◽  
Vol 130 (5) ◽  
pp. 615-629 ◽  
Author(s):  
Yves Alarie ◽  
Hélène Joly ◽  
Danielle Dennie
Keyword(s):  
Mass Spectrometer ◽  
Cuticular Hydrocarbons ◽  
Aquatic Insects ◽  
Cuticular Hydrocarbon ◽  
Hydrocarbon Composition ◽  
Gas Chromatograph ◽  
Cuticular Hydrocarbon Profile ◽  
Hydrocarbon Profile ◽  
Hydrocarbon Analysis ◽  
Aquatic Beetle

AbstractRelatively little information concerning the cuticular hydrocarbon composition of aquatic insects is known. The cuticular hydrocarbons of the aquatic beetle Agabus anthracinus Mannerheim have been identified with the aid of a gas chromatograph coupled to a mass spectrometer. The cuticular hydrocarbon profile comprises n-alkanes (46.8%), n-alkenes (27.1%), and methylalkanes (25.9%) and is basically similar to that of terrestrial Coleoptera. However, the hydrocarbons of A. anthracinus differ in that (i) the shorter chain n-alkanes are present in higher proportion, (ii) there is a relatively lower abundance of methylalkanes, and (iii) the proportion of n-alkenes is significantly higher.

scholarly journals Leaf geometric morphometrics among populations of Dalbergia ecastaphyllum (L.) Taub.

2019 ◽  
Vol 35 (6) ◽  
Author(s):  
Daniel Vieira de Morais ◽  
Lorena Andrade Nunes ◽  
Vandira Pereira da Mata ◽  
Maria Angélica Pereira de Carvalho Costa ◽  
Geni da Silva Sodré ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Geometric Morphometrics ◽  
Cross Validation ◽  
Abiotic Factors ◽  
Principal Component ◽  
Canonical Variate ◽  
Validation Test ◽  
Significant Difference ◽  
Variate Analysis ◽  
Geographical Distances

Leaves are plant structures that express important traits of the environment where they live. Leaf description has allowed identification of plant species as well as investigation of abiotic factors effects on their development, such as gases, light, temperature, and herbivory. This study described populations of Dalbergia ecastaphyllum through leaf geometric morphometrics in Brazil. We evaluated 200 leaves from four populations. The principal component analysis (PCA) showed that the first four principal components were responsible for 97.81% of variation. The non-parametric multivariate analysis of variance (NPMANOVA) indicated significant difference between samples (p = 0.0001). The Mentel test showed no correlation between geographical distances and shape. The canonical variate analysis (CVA) indicated that the first two variables were responsible for 96.77 % of total variation, while the cross-validation test showed an average of 83.33%. D. ecastaphyllum leaves are elliptical and ovate.

Changes in cuticular hydrocarbon composition in relation to age and sexual behavior in the female Calliphora Vomitoria (Diptera)

1988 ◽  
Vol 17 (2) ◽  
pp. 107-115 ◽  
Author(s):  
Marie Trabalon ◽  
Mireille Campan ◽  
Jean-Luc Clément ◽  
Bernard Thon ◽  
Catherine Lange ◽  
...  
Keyword(s):  
Sexual Behavior ◽  
Cuticular Hydrocarbon ◽  
Hydrocarbon Composition

scholarly journals Pleiotropic Effects of ebony and tan on Pigmentation and Cuticular Hydrocarbon Composition in Drosophila melanogaster

2019 ◽  
Vol 10 ◽  
Author(s):  
Jonathan H. Massey ◽  
Noriyoshi Akiyama ◽  
Tanja Bien ◽  
Klaus Dreisewerd ◽  
Patricia J. Wittkopp ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Cuticular Hydrocarbon ◽  
Hydrocarbon Composition ◽  
Pleiotropic Effects

scholarly journals Preliminary Study on the Differences in Hydrocarbons Between Phosphine-Susceptible and -Resistant Strains of Rhyzopertha dominica (Fabricius) and Tribolium castaneum (Herbst) Using Direct Immersion Solid-Phase Microextraction Coupled with GC-MS

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1565
Author(s):  
Ihab Alnajim ◽  
Manjree Agarwal ◽  
Tao Liu ◽  
Beibei Li ◽  
Xin Du ◽  
...  
Keyword(s):  
Cuticular Hydrocarbons ◽  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Rhyzopertha Dominica ◽  
Gas Chromatography Mass Spectrometry ◽  
Stored Grain ◽  
Phosphine Resistance ◽  
Significant Difference ◽  
Resistant Strains ◽  
Direct Immersion

Phosphine resistance is a worldwide issue threatening the grain industry. The cuticles of insects are covered with a layer of lipids, which protect insect bodies from the harmful effects of pesticides. The main components of the cuticular lipids are hydrocarbon compounds. In this research, phosphine-resistant and -susceptible strains of two main stored-grain insects, T. castaneum and R. dominica, were tested to determine the possible role of their cuticular hydrocarbons in phosphine resistance. Direct immersion solid-phase microextraction followed by gas chromatography-mass spectrometry (GC-MS) was applied to extract and analyze the cuticular hydrocarbons. The results showed significant differences between the resistant and susceptible strains regarding the cuticular hydrocarbons that were investigated. The resistant insects of both species contained higher amounts than the susceptible insects for the majority of the hydrocarbons, sixteen from cuticular extraction and nineteen from the homogenized body extraction for T. castaneum and eighteen from cuticular extraction and twenty-one from the homogenized body extraction for R. dominica. 3-methylnonacosane and 2-methylheptacosane had the highest significant difference between the susceptible and resistant strains of T. castaneum from the cuticle and the homogenized body, respectively. Unknown5 from the cuticle and 3-methylhentriacontane from the homogenized body recorded the highest significant differences in R. dominica. The higher hydrocarbon content is a key factor in eliminating phosphine from entering resistant insect bodies, acting as a barrier between insects and the surrounding phosphine environment.

scholarly journals Are there sex differences in the body size of the Eurasian red squirrel in Slovakia?

2015 ◽  
Vol 1 (1) ◽  
pp. 5-12 ◽  
Author(s):  
Alexander Čanády ◽  
Ladislav Mošanský ◽  
Peter Krišovský
Keyword(s):  
Function Analysis ◽  
Tail Length ◽  
The Body ◽  
Red Squirrel ◽  
Sexual Interaction ◽  
Mean Values ◽  
Foot Length ◽  
Significant Difference ◽  
Hind Foot ◽  
Males And Females

Abstract Sexual dimorphism of the Eurasian red squirrel on five somatic variables (head-and-body length, tail length, hind foot length, ear length and body weight) was evaluated on 55 squirrels. The overlap of values of the measured traits among sexes was high, but in all traits (with exception of the tail length) males seem to exhibit slightly higher mean values than females. However, these differences were non-significant, with the exception of a small significant difference in the tail length and tail-to-head-and-body ratio. Similarly, the results of discriminant function analysis show no differences between the sexes. Positive correlation analyses, together with PCA values, confirmed that tail length and hind foot length are traits that play a significant role in overall variability. We suggest that this relationship could explain their mutual importance in locomotion, where the feet are essential for movement in the trees. By contrast, the tail maintains balance on thin branches, or during jumps from one crown to another. Longer tails also demonstrate differential selection on males and females for a locomotor trait. Similarly, we discuss whether variations in tail length were connected to female reproductive success. Our results suggest that the non-significant results regarding SSD provide the benefit of the same size for both sexes in the protection of territory as well as inter- and intra-sexual interaction.

scholarly journals Clinical risk factors and predictive tool of bacteremia in patients with cirrhosis

2020 ◽  
Vol 48 (5) ◽  
pp. 030006052091922
Author(s):  
Qiao Yang ◽  
Xian Zhong Jiang ◽  
Yong Fen Zhu ◽  
Fang Fang Lv
Keyword(s):  
Risk Factors ◽  
Risk Assessment ◽  
Logistic Regression ◽  
Cross Validation ◽  
Bloodstream Infections ◽  
Roc Curves ◽  
Predictive Tool ◽  
Reactive Protein ◽  
Significant Difference ◽  
Fold Cross Validation

Objective We aimed to analyze the risk factors and to establish a predictive tool for the occurrence of bloodstream infections (BSI) in patients with cirrhosis. Methods A total of 2888 patients with cirrhosis were retrospectively included. Multivariate analysis for risk factors of BSI were tested using logistic regression. Multivariate logistic regression was validated using five-fold cross-validation. Results Variables that were independently associated with incidence of BSI were white blood cell count (odds ratio [OR] = 1.094, 95% confidence interval [CI] 1.063–1.127)], C-reactive protein (OR = 1.005, 95% CI 1.002–1.008), total bilirubin (OR = 1.003, 95% CI 1.002–1.004), and previous antimicrobial exposure (OR = 4.556, 95% CI 3.369–6.160); albumin (OR = 0.904, 95% CI 0.883–0.926), platelet count (OR = 0.996, 95% CI 0.994–0.998), and serum creatinine (OR = 0.989, 95% CI 0.985–0.994) were associated with lower odds of BSI. The area under receiver operating characteristic (ROC) curve of the risk assessment scale was 0.850, and its sensitivity and specificity were 0.762 and 0.801, respectively. There was no significant difference between the ROC curves of cross-validation and risk assessment. Conclusions We developed a predictive tool for BSI in patients with cirrhosis, which could help with early identification of such episodes at admission, to improve outcome in these patients.

scholarly journals LINEAR ASSESSMENT OF CEREBRAL AUTOREGULATION IN IDIOPATHIC PARKINSON'S DISEASE

2016 ◽  
Vol 8 (2) ◽  
pp. 14
Author(s):  
Chuang-chien Chiu ◽  
Ken Ying-kai Liao ◽  
Shoou-jeng Yeh
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Cerebral Autoregulation ◽  
System Analysis ◽  
Cerebral Blood Flow Velocity ◽  
Function Analysis ◽  
Control Group ◽  
Power Spectral ◽  
Significant Difference ◽  
Density Analysis

<p class="lead">Parkinson’s disease cases have been on the rise in the recent years, which promoted several different researches into the disorder. However, there hasn’t much research been done in the non-motor aspects of the disease. This study aims to improve the understanding of one of the non-motor symptoms of Parkinson’s disease. Specifically, this research aims to further understand cerebral autoregulation in patients with Parkinson’s disease. In order to achieve this aim, 25 subjects were recruited, with 11 healthy controls and 14 patients with Parkinson’s disease. The continuous blood pressure and continuous cerebral blood flow velocity of all subjects were recorded and processed while the subjects were at rest, tilt-up, and during hyperventilation. Linear signal and system analysis techniques were applied such as the power spectral density analysis and cross-correlation function analysis. Results showed that patients with Parkinson’s disease did not show a significant difference from the control group while at rest and after tilt-up. However, there was a significant difference between the groups during hyperventilation. The results obtained in this study suggested that the metabolic regulatory pathway for cerebral autoregulation is impaired in patients with Parkinson’s disease.</p>

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