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Butterflies are the best known invertebrates with an estimated 20,000 species worldwide and occupy a prominent place in conservation programmes and biodiversity assessments. However, there is a lack of knowledge on the butterfly fauna in Terengganu. A butterfly survey was conducted at the Terengganu National Park from 10 till 13 March 2011 by sweep netting aided by baited traps. A total of 81 butterflies belonging to 30 species from 18 genera and 5 families were identified. Nymphalidae (50.62%) was found to be the most dominant followed by Lycaenidae (30.86%) and Pieridae (12.35%) whereas Papilionidae (4.94%) and Hesperiidae (1.23%) were also recorded. The Common four-ring butterfly (Ypthima huebneri) and common caerulean butterfly (Jamides celeno alianus) were the most abundant recorded with 15 individuals and 13 individuals, respectively, making 18.52% and 16.05%, respectively of the total individuals sampled. A checklist of butterflies was presented as the outcome of the study. Result from this study was influenced by the sampling efforts which were restrained due to heavy rain and short timeframe during the sampling period. Comprehensive studies are recommended to expand overall knowledge and understanding of butterfly fauna in this forest. [ABSTRACT FROM AUTHOR]

Background Shellfish allergy in Singapore is highly prevalent, and shrimp allergy is the most common. Objective This study aims to evaluate the clinical characteristics and immunological phenotype of shellfish allergy in this population. Methods Patients with self-reported shellfish allergy were recruited from outpatient clinics of three large hospitals and from a population survey. Open oral food challenges ( OFC) to glass prawn ( Litopenaeus vannamei) and tiger prawn ( Penaeus monodon) were carried out on all patients except for those who had a history of severe anaphylaxis. Skin prick tests ( SPT) and specific Ig E to crude and recombinant allergens were carried out to evaluate shrimp and dust mite sensitization. Immunoblots were used to assess Ig E-binding proteins. Results The 104 patients recruited were categorized into shellfish allergic ( SA) when OFC was positive or had a history of severe anaphylaxis ( n = 39), shellfish tolerant ( ST) when OFC was negative ( n = 27), and house dust mite positive controls ( HDM+) who were ST ( n = 38). Oral symptoms (87.1%) were the predominant clinical manifestation. Positive challenge doses ranged from 2 to 80 g of cooked shrimp, with 25/52 patients reacting to either one or both shrimps challenged. The presence of specific Ig E to shrimp either by SPT and/or Immuno CAP® assay provided diagnostic test sensitivity of 82% and specificity of 22.2%. The inclusion of specific Ig E to shrimp tropomyosin and Ig E immunoblots with shrimp extracts did not improve the diagnostic proficiency substantially. Conclusions and Clinical Relevance This study highlights the predominance of oral symptoms in shrimp allergy in tropical Asia and that a high provocation dose may be necessary to reveal shrimp allergy. Furthermore, specific Ig E diagnostic tests and immunoblots were of limited use in this population. [ABSTRACT FROM AUTHOR]

The title complex crystallizes in the monoclinic P2[sub 1] /c space group, with a = 7.7397(8), b = 18.287(2), c = 17.4726(19) Å, β = 94.008(2)°, and Z = 4. The coordination geometry around the lithium cation is pseudooctahedral. The effects of lithium complexation on the [sup 1] H and [sup 13] C solution NMR spectra are discussed. In the solid-state [sup 13] C NMR spectrum at 300 K, very long aliphatic proton spin lattice relaxation times are observed along with broadening of the aliphatic carbon resonances. These results are attributed to the dipolar washout phenomenon, where the presence of a low amplitude motion of the same frequency as the [sup 1] H decoupler, leads to less effective removal of the [sup 1] H–[sup 13] C dipolar coupling. At 330 K, there is some sharpening of the aliphatic resonances since there is less interference between the motion and the decoupling frequency.Key words: crown ether analog, lithium complex.Le complexe mentionné dans le titre cristallise dans le groupe d'espace P2[sub 1] /c avec a = 7,7397(8), b = 18,287(2) et c = 17,4726(19) Å, β = 94,008(2)° et Z = 4. La géométrie de coordination autour du cation lithium est pseudooctaédrique. On discute des effets de la complexation avec le lithium sur les spectres RMN du [sup 1] H et du [sup 13] C. En RMN du [sup 13] C à l'état solide à 300 K, on observe que les temps de relaxation spin réseau des protons aliphatiques sont très longs et que les résonances des carbones aliphatiques sont élargies. Ces résultats sont attribués au phénomène d'épuration dipolaire dans lequel la présence d'un mouvement de faible amplitude de fréquence égale à celle du découpleur [sup 1] H conduit à une élimination moins efficace du couplage dipolaire [sup 1] H–[sup 13] C. À 330 K, les résonances aliphatiques deviennent plus précises parce qu'il y a moins d'interférence entre le mouvement et la fréquence de découplage.Mots clés : analogue d'éther couronne, complexe de lithium.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Treatment of naphtho-9-crown-3 ether with FeCl[sub 3 ] and aqueous H[sub 2] SO[sub 4] generates bis-naphtho-9-crown-3 ether in ca. 30% yield. This compound crystallizes in the monoclinic P2[sub 1] /n space group; a = 9.2004(9), b = 18.0868(17), and c = 13.2078(13) Å, β = 97.799(2)° and Z = 4. [sup 1] H and [sup 13] C NMR data have been obtained in solution, and the solid-state [sup 13] C NMR spectrum is included for comparison. A chemical shift range of ca. 12 ppm has been found for the oxygenated aliphatic carbons in the solid state, in contrast to the 3 ppm range in the solution [sup 13] C NMR spectrum. These results are discussed in terms of the torsional environments of the carbon sites in the crystal structure.Key words: crown ether, stereochemistry, oxidative dimerization.Le traitement de l'éther naphto-9-couronne-3 par du FeCl[sub 3] et du H[sub 2] SO[sub 4] aqueux conduit à la formation de l'éther bis-naphto-9-couronne-3 avec un rendement d'environ 30%. Ce composé cristallise dans le groupe d'espace P2[sub 1] /n avec a = 9,2004(9), b = 18,0868(17) et c = 13,2078(13) Å, β = 97,799(2)° et Z = 4. On a mesuré les spectres RMN du [sup 1] H et du [sup 13] C en solution et on a aussi déterminé le spectre RMN du [sup 13] C à l'état solide. Dans les spectres RMN du [sup 13] C à l'état solide, les déplacements chimiques des carbones aliphatiques oxygénés sont de l'ordre de 12 ppm alors qu'en solution on les retrouve vers 3 ppm. On discute de ces résultats en termes de l'environnement torsionnel des sites carbonés dans la structure cristalline.Mots clés : éther couronne, stéréochimie, dimérisation oxydante.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

The synthesis of a novel pyridine containing self-assembling system, L, is reported. This system is prepared from the reaction between 2,6-pyridinedicarboxylic acid, [pydc.H2], and 2,6-pyridinediamine, [pyda], in the presence of Et3N in THF as solvent in 88% yield. Double proton transfer from diacid to diamine results in the formation of a self-assembling system consisting of dicationic and dianionic units connecting through H-bonding and ion-pairing simultaneously as shown in the X-ray crystal structure. L is recrystallized from H2O. The crystal system is monoclinic with space group P21/c. One of the carboxylate anions of dianion unit is connected to and directed toward two ammonium cations of dication unit while the other one interacts with neighboring pyridine CH. The characterization was performed using EI, CI, ES mass spectroscopy as well as 1H and 13C solution NMR and X-ray crystal. The solid phase NMR, as a tool for conformation and structure prediction, reveals that the two–CO2− functional groups are not equally involved in the self-assembling system. The 13C solid phase NMR data is in agreement with X-ray crystal structure. [Copyright &y& Elsevier]

Background: Dengue fever, a diseases caused by Dengue virus (DENV) and transmitted to humans by Aedes aegypti and Aedes albopictus mosquitoes, has been hyper-endemic in Singapore for several decades. In the absence of an effective vaccine or specific treatment to mitigate the infections, control of Aedes mosquitoes plays a critical role in controlling the disease. In recent years, Singapore's vector control operations have been overwhelmed by geographical expansion of dengue transmission as well as increasing magnitude of epidemics. At the same time, they have been hampered by the lack of tools to assess the impending risk of dengue fever outbreaks spatially and manpower insufficiency. Methods & Materials: To help operation department allocate limited resources, we developed a predictive risk map for dengue transmission using the Random Forest algorithm, incorporating various risk factors and accounting for temporal and spatial lag effects of the factors. A wide range of factors representing the characteristics of past dengue situation (total number of cases in previous year and number of non-resident cases in previous year), human population (estimated population density), vector population (estimated ratio of Aedes aegypti mosquitoes out of all Aedes moquitoes--breeding percentage) and environment (vegetation index, connectivity index and ratio of residential area) were examined and incorporated in the model. Results: Validation using most recent data showed that the observed and the predicted risk ranks had a Pearson correlation of 0.87 (P < 0.001) and a weighted Kappa agreement of 0.814 (P < 0.001) when categorised to risk groups. In addition, the model was able to estimate the partial effects and relative importance of individual risk factors, which can strengthen our understanding of the risk factors of dengue transmission. Conclusion: Our risk map has strong predictive capability, hence may be an important tool in guiding targeted vector control interventions for dengue. [ABSTRACT FROM AUTHOR]