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1.  Diversity of the Photoreceptors and Spectral Opponency in the Compound Eye of the Golden Birdwing, Troides aeacus formosanus 
PLoS ONE  2013;8(4):e62240.
The compound eye of the Golden Birdwing, Troides aeacus formosanus (Papilionidae, Lepidoptera), is furnished with three types of ommatidia, which are clearly different in pigmentation around the rhabdom. Each ommatidium contains nine photoreceptors, whose spectral sensitivities were analyzed electrophysiologically. We identified nine spectral types of photoreceptor with sensitivities peaking at 360 nm (UV), 390 nm (V), 440 nm (B), 510 nm (BG), 540 nm (sG), 550 nm (dG), 580 nm (O), 610 nm (R), and 630 nm (dR) respectively. The spectral sensitivities of the V, O, R and dR receptors did not match the predicted spectra of any visual pigments, but with the filtering effects of the pigments around the rhabdom, they can be reasonably explained. In some of the receptors, negative-going responses were observed when they were stimulated at certain wavelengths, indicating antagonistic interactions between photoreceptors.
doi:10.1371/journal.pone.0062240
PMCID: PMC3627921  PMID: 23614043
2.  Impaired Olfactory Associative Behavior of Honeybee Workers Due to Contamination of Imidacloprid in the Larval Stage 
PLoS ONE  2012;7(11):e49472.
The residue of imidacloprid in the nectar and pollens of the plants is toxic not only to adult honeybees but also the larvae. Our understanding of the risk of imidacloprid to larvae of the honeybees is still in a very early stage. In this study, the capped-brood, pupation and eclosion rates of the honeybee larvae were recorded after treating them directly in the hive with different dosages of imidacloprid. The brood-capped rates of the larvae decreased significantly when the dosages increased from 24 to 8000 ng/larva. However, there were no significant effects of DMSO or 0.4 ng of imidacloprid per larva on the brood-capped, pupation and eclosion rates. Although the sublethal dosage of imidacloprid had no effect on the eclosion rate, we found that the olfactory associative behavior of the adult bees was impaired if they had been treated with 0.04 ng/larva imidacloprid in the larval stage. These results demonstrate that a sublethal dosage of imidacloprid given to the larvae affects the subsequent associative ability of the adult honeybee workers. Thus, a low dose of imidacloprid may affect the survival condition of the entire colony, even though the larvae survive to adulthood.
doi:10.1371/journal.pone.0049472
PMCID: PMC3498130  PMID: 23166680
3.  Antimicrobial activity of bacteriocin-producing lactic acid bacteria isolated from cheeses and yogurts 
AMB Express  2012;2:48.
The biopreservation of foods using bacteriocinogenic lactic acid bacteria (LAB) isolated directly from foods is an innovative approach. The objectives of this study were to isolate and identify bacteriocinogenic LAB from various cheeses and yogurts and evaluate their antimicrobial effects on selected spoilage and pathogenic microorganisms in vitro as well as on a food commodity.
LAB were isolated using MRS and M17 media. The agar diffusion bioassay was used to screen for bacteriocin or bacteriocin-like substances (BLS) producing LAB using Lactobacillus sakei and Listeria innocua as indicator organisms. Out of 138 LAB isolates, 28 were found to inhibit these bacteria and were identified as strains of Enterococcus faecium, Streptococcus thermophilus, Lactobacillus casei and Lactobacillus sakei subsp. sakei using 16S rRNA gene sequencing. Eight isolates were tested for antimicrobial activity at 5°C and 20°C against L. innocua, Escherichia coli, Bacillus cereus, Pseudomonas fluorescens, Erwinia carotovora, and Leuconostoc mesenteroides subsp. mesenteroides using the agar diffusion bioassay, and also against Penicillium expansum, Botrytis cinerea and Monilinia frucitcola using the microdilution plate method. The effect of selected LAB strains on L. innocua inoculated onto fresh-cut onions was also investigated.
Twenty percent of our isolates produced BLS inhibiting the growth of L. innocua and/or Lact. sakei. Organic acids and/or H2O2 produced by LAB and not the BLS had strong antimicrobial effects on all microorganisms tested with the exception of E. coli. Ent. faecium, Strep. thermophilus and Lact. casei effectively inhibited the growth of natural microflora and L. innocua inoculated onto fresh-cut onions. Bacteriocinogenic LAB present in cheeses and yogurts may have potential to be used as biopreservatives in foods.
doi:10.1186/2191-0855-2-48
PMCID: PMC3488010  PMID: 22963659
Lactic acid bacteria; Bacteriocins; Bacteriocin-like substance (BLS); Antimicrobials; Fresh-cut onions
4.  Diaqua­bis­[5-(2-pyridyl­meth­yl)tetra­zol­ato-κ2 N 1,N 5]zinc(II) 
In the title mononuclear complex, [Zn(C7H6N5)2(H2O)2], the ZnII atom, located on an inversion centre, is in a distorted octa­hedral coordination geometry formed by four N atoms from two chelating 5-(2-pyridyl­meth­yl)tetra­zolate ligands and two O donors from two water mol­ecules. Inter­molecular O—H⋯N hydrogen bonds between the coordinated water mol­ecule and the tetra­zolyl group of the 5-(2-pyridyl­meth­yl)tetra­zolate ligand lead to the formation of a three-dimensional network.
doi:10.1107/S1600536811019507
PMCID: PMC3120314  PMID: 21754679
5.  Benzimidazolium 3,5-dicarb­oxy­benzoate trihydrate 
Cocrystallization of benzimidazole with benzene 1,3,5-tricarb­oxy­lic acid in slightly basic medium afforded the title compound, C7H7N2 +·C9H5O6 −·3H2O, in which one of the imidazole N atom is protonated and one carb­oxy­lic group of aromatic acid is deprotonated. In the crystal structure, inter­molecular N—H⋯O hydrogen-bonding connects the two organic components into dimers, which are further linked into a three-dimensional network by O—H⋯O and N—H⋯O inter­actions between the water mol­ecules and the dimers.
doi:10.1107/S1600536810023305
PMCID: PMC3006944  PMID: 21587955
6.  catena-Poly[[[diaqua­copper(II)]-bis­[μ2-1,3-bis­(1,2,4-triazol-1-yl)propane]] dinitrate monohydrate] 
The title CuII coordination polymer, {[Cu(C7H10N6)2(H2O)2](NO3)2·H2O}n, was obtained by the reaction of equimolar Cu(NO3)2·4H2O and 1,3-bis­(1,2,4-triazol-1-yl)propane (btp) in a water–methanol solvent. The CuII atom is located on a centre of inversion and has an elongated octa­hedral coordination geometry formed by four N atoms from four symmetry-related btp ligands and two coordinated water mol­ecules. Adjacent CuII atoms are connected by btp ligands, generating a double-stranded chain. The nitrate anion is disordered over two positions in a 0.828 (7):0.172 (2) ratio.
doi:10.1107/S1600536809035958
PMCID: PMC2970232  PMID: 21577727
7.  catena-Poly[[[bis­(1,10-phenanthroline-κ2 N,N′)manganese(II)]-μ-9,10-dioxo­anthracene-1,5-disulfonato-κ2 O 1:O 5] tetra­hydrate] 
The title complex, {[Mn(C14H6O8S2)(C12H8N2)2]·4H2O}n, exhibits a chain-like polymeric structure with 9,10-dioxo­anthracene-1,5-disulfonate anions bridging MnII atoms in a bis-monodentate mode. The unique MnII atom is located on a crystallographic centre of inversion. Four N atoms from two chelating 1,10-phenanthroline ligands and two sulfonate O atoms from two symmetry-related 9,10-dioxoanthracene-1,5-disulfonate anions give rise to a slightly distorted octa­hedral coordination environment around the MnII centre. The centroid of the central ring of the anthraquinone ligand represents another crystallographic centre of inversion. In the crystal structure, inter­ligand π–π stacking [centroid-to-centroid distances 3.532 (1) and 3.497 (3) Å] and inter­molecular O—H⋯O hydrogen-bonding inter­actions assemble the chains into a three-dimensional supra­molecular network.
doi:10.1107/S1600536809019503
PMCID: PMC2969754  PMID: 21583051
8.  CoCMA: Energy-Efficient Coverage Control in Cluster-Based Wireless Sensor Networks Using a Memetic Algorithm 
Sensors (Basel, Switzerland)  2009;9(6):4918-4940.
Deployment of wireless sensor networks (WSNs) has drawn much attention in recent years. Given the limited energy for sensor nodes, it is critical to implement WSNs with energy efficiency designs. Sensing coverage in networks, on the other hand, may degrade gradually over time after WSNs are activated. For mission-critical applications, therefore, energy-efficient coverage control should be taken into consideration to support the quality of service (QoS) of WSNs. Usually, coverage-controlling strategies present some challenging problems: (1) resolving the conflicts while determining which nodes should be turned off to conserve energy; (2) designing an optimal wake-up scheme that avoids awakening more nodes than necessary. In this paper, we implement an energy-efficient coverage control in cluster-based WSNs using a Memetic Algorithm (MA)-based approach, entitled CoCMA, to resolve the challenging problems. The CoCMA contains two optimization strategies: a MA-based schedule for sensor nodes and a wake-up scheme, which are responsible to prolong the network lifetime while maintaining coverage preservation. The MA-based schedule is applied to a given WSN to avoid unnecessary energy consumption caused by the redundant nodes. During the network operation, the wake-up scheme awakens sleeping sensor nodes to recover coverage hole caused by dead nodes. The performance evaluation of the proposed CoCMA was conducted on a cluster-based WSN (CWSN) under either a random or a uniform deployment of sensor nodes. Simulation results show that the performance yielded by the combination of MA and wake-up scheme is better than that in some existing approaches. Furthermore, CoCMA is able to activate fewer sensor nodes to monitor the required sensing area.
doi:10.3390/s90604918
PMCID: PMC3291946  PMID: 22408561
wireless sensor network; sensing coverage; energy efficiency; memetic algorithm
9.  ESEEM Studies of Peptide Nitrogen Hyperfine Coupling in Tyrosyl Radicals and Model Peptides 
The journal of physical chemistry. B  2007;111(23):6586-6592.
Tyrosyl radicals are important in long-range electron transfer in several enzymes, but the protein environmental factors that control midpoint potential and electron transfer rate are not well understood. To develop a more detailed understanding of the effect of protein sequence, we have performed 14N and 15N electron spin echo envelope modulation (ESEEM) measurements on tyrosyl radical, generated either in polycrystalline tyrosinate or in its 15N labeled isotopomer, by UV photolysis. 14N ESEEM was also performed on tyrosyl radical generated in tyrosine-containing pentapeptide samples. Simulation of the 14N and 15N tyrosyl radical ESEEM measurements yielded no significant isotropic hyperfine splitting to the amine or amide nitrogen; the amplitude of the anisotropic, nitrogen hyperfine coupling (0.21 MHz) was consistent with a dipole-dipole distance of 3.0 Å. Density functional theory was used to calculate the isotropic and anisotropic hyperfine couplings to the amino nitrogen in four different tyrosyl radical conformers. Comparison with the simulated data suggested that the lowest energy radical conformer, generated in tyrosine at pH 11, has a 76° Cα-Cβ-C1′-C2′ ring and a −73° C-Cα-Cβ-C1′ backbone dihedral angle. In addition, the magnitude, orientation, and asymmetry of the nuclear quadrupole coupling tensor were derived from analysis of the tyrosyl radical 14N ESEEM. The simulations showed differences in the coupling and orientation of the nuclear quadrupole tensor, when the tyrosinate and pentapeptide samples were compared. These results suggest sequence- or conformation-induced changes in the ionic character of the NH bond in different tyrosine-containing peptides.
doi:10.1021/jp071402x
PMCID: PMC2518650  PMID: 17518496
electron transfer; redox-active amino acid; EPR; peptide bond; UV-photolysis; tyrosine
10.  Quantification of human bocavirus in lower respiratory tract infections in China 
A quantitative PCR method was established to quantify human bocavirus (HBoV) genomic copies in clinical specimens from children with lower respiratory tract infections (LRTI) in China. A total of 257 respiratory tract specimens were tested, and 7 (2.7%) of these (all sputum samples) were positive, with genomic copies that ranged from 8.0 × 103 to 8.0 × 109 in the samples. The main clinical symptom of patients who were positive for HBoV DNA was a pneumonia-like syndrome represented by high fever and cough. Our results suggest that HBoV may be an important etiological agent of LRTI in children in China.
doi:10.1186/1750-9378-2-3
PMCID: PMC1796861  PMID: 17266760

Results 1-10 (10)