Technological process optimization and measurement of image quality of the electrically bifocal metalens.

This Letter describes the design procedure and process optimization of the electrically bifocal metalens. In our design, horizontal and vertical polarization is manipulated by applying a suitable voltage to a twisted nematic liquid crystal (TN-LC) cell. Each nanostructure is designed to be a rectangular prism, making different polarizations of light experience various phase delays, thus causing bi-focus. We selected lithographical methods to fabricate our metalens because of the minimum physical size, which can be as small as 50 nm, and the maximum aspect ratio, which is as high as 15. Furthermore, to increase the tolerance and make the sidewall vertical and smooth, we coated different characteristics of photoresist sensitivity to the upper and lower layers. After the development, the mushroom-type photoresist makes Ni easier to strip while in the lift-off process, thus increasing the quality of the whole metalens. Our experiment shows that the focal lengths and focusing efficiencies corresponding to the two polarizations are similar to the simulation results. The proposed electrically modulated bifocal metalens can be utilized in different applications and combined with other optical components.

A review of the legged mealybugs on bamboo (Hemiptera: Coccoidea: Pseudococcidae) occurring in China.

Twenty-two species of legged mealybugs occur on bamboo (Poaceae: Bambusoideae) in China. These species are reviewed and two of them are described for the first time: Dysmicoccus luoyangensis Li & Wu, sp. nov. and Trionymus indocalamus Li & Wu, sp. nov. Two new combinations are established: Pseudococcus bambusicola Takahashi and Kaicoccus bambusus Wu are transferred to genus Formicococcus Takahashi as F. bambusicola (Takahashi) comb. nov. and F. bambusus (Wu) comb. nov., respectively. Formicococcus bambusicola, Heliococcus bambusae (Takahashi), Neoripersia miscanthicola Takahashi and Trionymus formosanus Takahashi are redescribed and reillustrated based on type specimens. Brief notes are provided for Balanococcus kwoni Pellizari & Danzig, B. zhejiangensis Li & Wu, Dysmicoccus dengwuensis Ferris, D. indocalamus Wu, Eumyrmococcus smithii Silvestri, Ferrisicoccus angustus Ezzat & McConnell, Heliococcus lingnaniae Wang, H. takae (Kuwana), Heterococcus abludens Borchsenius, Miscanthicoccus miscanthi (Takahashi), Palmicultor lumpurensis (Takahashi), Paraporisaccus guizhouensis Lu & Wu, Paraserrolecanium fargesii Wu, Pseudantonina magnotubulata Borchsenius and Trionymus bambusae (Green). A key to the species of legged mealybugs on bamboo occurring in China is given. A list of bamboo mealybugs worldwide is also provided. 

Synthesis and two-photon absorption property characterizations of small dendritic chromophores containing functionalized quinoxaliniod heterocycles.

A series of star-shaped multi-polar chromophores (compounds 1-3) containing functionalized quinoxaline and quinoxalinoid (indenoquinoxaline and pyridopyrazine) units has been synthesized and characterized for their two-photon absorption (2PA) properties both in the femtosecond and the nanosecond time domain. Under our experimental conditions, these model fluorophores are found to manifest strong and wide-dispersed two-photon absorption in the near-infrared region. It is demonstrated that molecular structures with multi-branched π frameworks incorporating properly functionalized quinoxalinoid units would possess large molecular nonlinear absorptivities within the studied spectral range. Effective optical-power attenuation and stabilization behaviors in the nanosecond time domain of a selected representative dye molecule (i.e., compound 2) from this model compound set were also investigated and the results indicate that such structural motif could be a useful approach for the molecular design toward strong two-photon-absorbing material systems for quick-responsive and broadband optical-suppressing-related applications, particularly to confront long laser pulses.

A new Chorizococcus species (Coccoidea, Pseudococcidae) from Taiwan with transferring of Chorizococcus mirzayansi Moghaddam to genus Spilococcus Ferris.

A new mealybug species, Chorizococcus zoysiaesp. n., feeding on Zoysia tenuifolia (Poaceae), is described from Taiwan. Adult female, third-instar female, second-instar female and first-instar nymph were described and illustrated in this article. Keys are provides to (a) separate this new species from similar species of Chorizococcus and those of same genus on zoysia grasses and (b) to identify instars of the new species. In addition, Chorizococcus mirzayansi Moghaddam is transferred to the genus Spilococcus as Spilococcus mirzayansi (Moghaddam), comb. n.

Identification and synthesis of the sex pheromone of the Madeira mealybug, Phenacoccus madeirensis Green.

Two components were identified from aeration extracts of the virgin female Madeira mealybug, Phenacoccus madeirensis as trans-(1R,3R)-chrysanthemyl (R)-2-methylbutanoate and (R)-lavandulyl (R)-2-methylbutanoate (with a ratio of 3:1) by a combination of gas chromatography retention time matches, mass spectrometry, and microchemical tests. The structures and chirality of the compounds were confirmed by comparing with synthetic compounds. The synthetic trans-(1R,3R)-chrysanthemyl (R)-2-methylbutanoate was highly attractive to males in laboratory bioassays; the synthetic (R)-lavandulyl (R)-2-methylbutanoate was weakly attractive. No synergistic effect was observed when the mixture of the two compounds was tested.

Pilot study on the "quality of life" as reflected by psychosocial adjustment of children with thalassemia major undergoing iron-chelating treatment in western Taiwan.

Comprehensive care for thalassemia major (TM) patients has achieved great advances in the world, yet psychosocial developmental aspects of care in families with afflicted members has made only limited progress. Besides confronting the disease itself, a major task for children with TM is to develop into autonomous, healthy, and functioning adults. An emerging concept in considering the adjustment of children with chronic physical disorders is "quality of life"(QL). To study the QL with regard to reflection by psychosocial adjustment in TM children, we enrolled 55 TM patients undergoing intravenous (IV) and/or oral iron chelation, 39 of whom completed the content on issues related to QL according to Cramer and Devinsky. It was concluded that oral iron chelation can be better adjusted than IV iron chelation for a thalassemic child. This favors its use, but not necessarily in combination with IV iron chelation. Perception gaps that arise from age or generation merit concern. This approach to the study of QL, as reflected by psychosocial adjustment in children with TM, is an excellent method for learning about parental-child adjustment regarding a chronic physical condition such as TM.

Pilot study on parental stress and behavioral adjustment to the thalassemia major disease process in children undergoing iron-chelation in western Taiwan.

Thalassemia was first described by Cooley and Lee in 1952 in several Italian children as a severe anemia with spleen and liver enlargement, skin discoloration, and bony changes. Great strides in management and intervention have not been matched by progress in psychosocial rehabilitation. Because parental stress and adaptation are of concern, this study focuses on parental stress and adjustment in response to the disease process of their afflicted children in western Taiwan. The parents of 18 thalassemia major patients (under 12 years of age) were interviewed (in two sessions) to determine their feelings, sources of stress, and support during their childrens' disease process. The study found that: 1) many parents suffer from stress as a result of the disease process, 2) all parents had similar concerns about iron chelation treatment, and 3) some resilience factors were present in the support system.