• Advances in nano research
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• v.17 no.1
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• pp.75-86
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• 2024

The insecticidal efficiency of orange (Citrus sinensis) peel essential oil (OP-EO) is limited because of its low stability under environmental conditions. Nanoemulsion formulations show promise in overcoming this limitation. Therefore, this study aimed to formulate and characterize the OP-EO nanoemulsion form (OP-EON) and investigate its insecticidal properties against two significant storage pests, Rhyzopertha dominica (Fabricius, 1792), and Tribolium castaneum (Herbst, 1797). The OP-EON (4:3:3:90 w/w, EO: Tween 80: Ethanol: water) was successfully created using an ultrasonic homogenizer. The major chemical components of the OP-EO were determined to be D-limonene (87.93%), myrcene (3.62%), and α-pinene (1.34%) through GC-MS analysis. The OP-EON was characterized using TEM (50-100 nm), Zeta sizer (the mean droplet particle size of 58.60 nm, the ζ-potential value of -12.6 mV, and the polydispersity index of 0.486), and FT-IR analysis. After 7 days, exposure to 500 ppm of the OP-EON resulted in 50% and 30% mortality rates in R. dominica and T. castaneum, respectively. Exposure to 1000 ppm of OP-EON resulted in 90% and 55% mortality in R. dominica and T. castaneum, respectively, after 7 days. Overall, these results clearly showed the potential to exceed the limits of the insecticidal activity of the OP-EO with its nanoemulsion form.

• Journal of English Language & Literature
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• v.55 no.3
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• pp.441-458
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• 2009

The Imperial Road is Jean Rhys s unfinished manuscript, rejected by publishers for its openly racist tone. Although it describes Rhys s actual visit to Dominica in 1936, it is not a transparent recollection of the travel but a recreation informed by racial dynamics of the 1970s when she wrote the text. This paper examines the manuscript as a troubled (and troubling) response to what Rhys perceived as racial rejection from Dominica at the wake of political independence. Rhys s representation of white Creole womanhood significantly depends on an interwoven configuration of racial dynamics and sexual politics, where an oppressive white European man facilitates a white Creole woman s cross-racial identification with Afro-Caribbeans. However, the political and literary landscape of the West Indies in the 1970s made such cross-racial identification untenable. As a result, The Imperial Road is full of disturbing racial hatred, prejudice, and resentment. And yet, it also reflects Rhys s honest and serious concern over a white Creole s racial identity in postcolonial Dominica, raising a difficult question: How would a postcolonial age change a white Creole identity that belongs neither to the colonized nor to the colonizer (or both)? In The Imperial Road, unable to identify with Afro-Caribbeans, the white Creole is disoriented in time and space, lost at home, stuck between the past and the present, not knowing how to participate in a postcolonial homeland. Through the narrator s racial disorientation, The Imperial Road exposes the white Creole s fundamental dependence on other Creoles.

• Korean journal of applied entomology
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• v.15 no.1 s.26
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• pp.47-48
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• 1976

• Korean journal of applied entomology
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• v.22 no.1 s.54
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• pp.30-34
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• 1983

Authors identified following seven species of six genera of Dinoderinae and Bostrichinae of Bostrichidae intercepted from imported logs. Keys and descriptions are given for the seven species. The distribution of each species is outlined Dinoderinae: Rizopertha dominica (Fabricius) Dinoderus minutus (Fabricius) Bostrichinae: Sinoxylon anale Lesne S. japonicum Lesne Heterobostrychus hamatipennis (Lesne) Xylothrips flavipes (Illiger) Xylopsocus castanopterus (Fairmair).

• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.69-79
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• 2012

In an ongoing survey of the bioactive potential of microorganisms from Ladakh, India, the culture medium of a bacterial strain of a new Pseudomonas sp., strain ICTB-745, isolated from an alkaline soil sample collected from Leh, Ladakh, India, was found to contain metabolites that exhibited broad-spectrum antimicrobial and biosurfactant activities. Bioactivity-guided purification resulted in the isolation of four bioactive compounds. Their chemical structures were elucidated by $^1H$ and $^{13}C$ NMR, 2D-NMR (HMBC, HSQC, $^1H$,$^1H$-COSY, and DEPT-135), FT-IR, and mass spectroscopic methods, and were identified as 1-hydroxyphenazine, phenazine-1-carboxylic acid (PCA), rhamnolipid-1 (RL-1), and rhamnolipid-2 (RL-2). These metabolites exhibited various biological activities like antimicrobial and efficient cytotoxic potencies against different human tumor cell lines such as HeLa, HepG2, A549, and MDA MB 231. RL-1 and RL-2 exhibited a dose-dependent antifeedant activity against Spodoptera litura, producing about 82.06% and 73.66% antifeedant activity, whereas PCA showed a moderate antifeedant activity (63.67%) at 60 ${\mu}g/cm^2$ area of castor leaf. Furthermore, PCA, RL-1, and RL-2 exhibited about 65%, 52%, and 47% mortality, respectively, against Rhyzopertha dominica at 20 ${\mu}g/ml$. This is the first report of rhamnolipids as antifeedant metabolites against Spodoptera litura and as insecticidal metabolites against Rhyzopertha dominica. The metabolites from Pseudomonas sp. strain ICTB-745 have interesting potential for use as a biopesticide in pest control programs.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.103-108
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• 2002

We describe here the cDNA sequence and mRNA expression of a novel serine pretense from the firefly, Pyrocoelia rufa. The 771 bp cDNA encodes for 257 amino acid residues. The deduced protein of P. rufa serine pretense gene contains the catalytic triad and six-conserved cysteine residues. Alignment of the deduced protein of P. rufa serine pretense gene showed 47.4% protein sequence identity to known coleopteran insect Rhyzopertha dominica midgut trpsin-like enzyme. Northern blot analysis revealed that the P. rufa serine pretense is specifically expressed in the midgut of P. rufa larvae.