Cortex Thickness Is Key for the Colors of Iridescent Starling Feather Barbules With a Single, Organized Melanosome Layer

The iridescent plumage of many birds is structurally colored due to an orderly arrangement of melanosomes in their feather barbules. Here, we investigated the blue- to purple-colored feathers of the European starling (Sturnus vulgaris) and the blue and green feathers of the Cape starling (Lamprotornis nitens). In both cases, the barbules contain essentially a single layer of melanosomes, but in S. vulgaris they are solid and rod-shaped, and in L. nitens they are hollow and rod- as well as platelet-shaped. We analyzed the coloration of the feathers by applying imaging scatterometry, bifurcated-probe- and micro-spectrophotometry. The reflectance spectra of the feathers of the European starling showed multiple peaks and a distinct, single peak for the Cape starling feathers. Assuming that the barbules of the two starling species contain a simple multilayer, consisting locally only of a cortex plus a single layer of melanosomes, we interpret the experimental data by applying effective-medium-multilayer modeling. The optical modeling provides quantitative insight into the function of the keratin cortex thickness, being the principal factor to determine the peak wavelength of the reflectance bands; the melanosome layer only plays a minor role. The air cavity in the hollow melanosomes of the Cape starling creates a strongly enhanced refractive index contrast, thus very effectively causing a high reflectance.

Cortical myosin minifilaments orchestrate the arrangement of microridge protrusions on epithelial cell surfaces

ABSTRACTActin-based protrusions vary in morphology, stability, and arrangement on cell surfaces. Microridges are laterally-elongated protrusions arranged in maze-like patterns on mucosal epithelial cells that rearrange dynamically by fission and fusion. To characterize how microridges mature and investigate the mechanisms driving fission and fusion, we imaged microridges in the maturing skin of zebrafish larvae. After their initial development, microridges continued to lengthen and microridge alignment became increasingly well ordered. Imaging F-actin and Non-Muscle Myosin II (NMII) revealed that microridge fission and fusion were associated with local NMII activity in the apical cortex. Inhibiting NMII blocked rearrangements, reduced microridge density, and altered microridge spacing. High-resolution imaging revealed that individual cortical NMII minifilaments are tethered to protrusions, often connecting adjacent microridges. NMII minifilaments connecting the ends of microridges fused them together, whereas minifilaments oriented perpendicular to microridges severed them or pulled them closer together. Our findings demonstrate that as cells mature, microridges continue to remodel and form an increasingly orderly arrangement through a process orchestrated by cortical NMII contraction.

ILMU RASM QURAN

The science of rasm of the Al-Qur’an is the study of the writing of the mushaf of the Al-Qur’an which is carried out in a special way, both in the writing of the pronunciations and the forms of letters used. Writing of the Al-Qur’an during the time of the Prophet Muhammad. Performed by his friends both in writing and in order with the aim to unite the Muslims in one type of Manuscripts by uniforming the reading and unifying the orderly arrangement of the verses. Thus there is no difference in understanding between the Manuscripts with other Manuscripts.

Preparation and Drilling Performance of Orderly Arranged Diamond Bit

This paper introduces the application of orderly arranged diamond bit and the technology of realizing diamond orderly arrangement in bit. Two kinds of conventional bits and one bit with diamond orderly arrangement were used in the test to drill reinforced concrete. By experimental results: under the same conditions (same matrix, same diamond grade and concentration), the drilling speed of orderly arranged diamond bit is increased by 13.1%, the life is increased by 11.5%, compared with the conventional diamond bit. The drilling speed of orderly arranged diamond bit is increased by 15.8%, the life is increased by 8.9%, compared with the conventional bit which the matrix is same but the diamond concentration is 5% higher. On the basis of saving diamond and reducing cost of bit, orderly arrangement can still improve the efficiency and life of drill bit, it embodies the superiority of diamond bit with diamond orderly arrangement.

Development of Theophylline Microbeads Using PregelatinizedBreadfruit Starch (Artocarpus altilis) as a Novel Co-polymer for Controlled Release

Purpose: The aim of this study was to prepare formulations of theophylline microbeads usingpregelatinized breadfruit starch (Artocarpus altilis, family Moraceae) in combination withsodium alginate and chitosan at various polymer: drug ratios. Microbead formulations forcontrolled delivery of theophylline would be better alternatives to conventional dosage formsfor optimized drug therapy.Methods: The native and pregelatinized starches were characterized for morphology (scanningelectron microscope), crystallinity (Fourier transform intra-red spectroscopy, FTIR and X-raydiffractometer, XRD), thermal flow (differential scanning colorimeter), density and flowproperties. Theophylline microbeads were prepared by ionic gelation and characterized usingsize, swelling index, entrapment efficiency and time required for 15% and 50% drug release (t15and t50 respectively).Results: FTIR and XRD spectra revealed the orderly arrangement of granules of the semi-crystallinebreadfruit starch was disrupted on gelatinization. The viscosity and flow of pregelatinized starchwere enhanced. Theophylline microbeads were near spherical in shape with size range 1.09± 0.672 to 1.58 ± 0.54 mm. FTIR and XRD spectra confirmed there was no drug-polymerinteraction. Microsphere size, swelling increased while entrapment and dissolution time (t50)reduced with polymer: drug ratio. The entrapment efficiency ranged from 30.99 ± 1.32 to 78.50± 2.37%. Optimized formulation, starch: alginate ratio 3:1 at polymer: drug ratio of 2:1, gave aprolonged dissolution time (t50 = 8.40 ± 1.20 h).Conclusion: Breadfruit starch was suitable as a copolymer for the controlled delivery oftheophylline in microbeads which could serve as a substitute to synthetic polymers in drugdelivery.

Rational design of a new chalcogenide with good infrared nonlinear optical performance: SrZnSnS4

The new nonlinear optical material SrZnSnS4 is a two-dimensional layer structure with a large band gap (3.37 eV). The orderly arrangement of [ZnS4]6− and [SnS4]4− groups mainly contribute to the second harmonic generation effect (∼LiGaS2).

Photocontrolled protein assembly for constructing programmed two-dimensional nanomaterials

A rapid and efficient strategy was developed to construct photocontrolled 2D protein nanosheets with an orderly arrangement.