Transcriptomic Analysis Suggests Auxin Regulation in Dorsal-Ventral Petal Asymmetry of Wild Progenitor Sinningia speciosa

The establishment of dorsal–ventral (DV) petal asymmetry is accompanied by differential growth of DV petal size, shape, and color differences, which enhance ornamental values. Genes involved in flower symmetry in Sinningia speciosa have been identified as CYCLOIDEA (SsCYC), but which gene regulatory network (GRN) is associated with SsCYC to establish DV petal asymmetry is still unknown. To uncover the GRN of DV petal asymmetry, we identified 630 DV differentially expressed genes (DV-DEGs) from the RNA-Seq of dorsal and ventral petals in the wild progenitor, S. speciosa ‘ES’. Validated by qRT-PCR, genes in the auxin signaling transduction pathway, SsCYC, and a major regulator of anthocyanin biosynthesis were upregulated in dorsal petals. These genes correlated with a higher endogenous auxin level in dorsal petals, with longer tube length growth through cell expansion and a purple dorsal color. Over-expression of SsCYC in Nicotiana reduced petal size by regulating cell growth, suggesting that SsCYC also controls cell expansion. This suggests that auxin and SsCYC both regulate DV petal asymmetry. Transiently over-expressed SsCYC, however, could not activate most major auxin signaling genes, suggesting that SsCYC may not trigger auxin regulation. Whether auxin can activate SsCYC or whether they act independently to regulate DV petal asymmetry remains to be explored in the future.     

Emission of polycyclic aromatic hydrocarbons from the pyrolysis of liquid crystal wastes

A liquid crystal display can be described as a panel consisting of two plates of glass with liquid crystals in the space between. Generally, the liquid crystal wastes are extracted and separated into various fractions. Some recyclable materials, i.e., metals, glass, plastics, etc., are recycled, but the liquid crystals are incinerated. The emission factors for 16 U.S. EPA priority polycyclic aromatic hydrocarbons (PAHs) from the combustion of liquid crystal are approximately 390 and 1520 times higher than that of waste terephthalic acid and biological sludge combustion, respectively. In this study, we determined the emission of PAHs from the liquid crystals pyrolysis. We also investigated the fragments and gas compositions using on-line thermogravimetry–mass spectrometry (TG–MS). A temperature series of 14 fragments was analyzed in nitrogen, and was found to include m/z: 30, 32, 42, 44, 55, 57, 67, 81, 95, 109, 128, 166, 178, and 202. The fragments at m/z 32 represents formaldehyde and the fragment at m/z 44 is carbon dioxide. The fragments at m/z 55, 57, 67, 81, 95, and 109 represent hydrocarbon components, all of which may be liquid crystal by products. The TG–MS as analyzed above can offer a better understanding of the mechanisms of byproduct formation in liquid crystal waste pyrolysis.Experimentally, not detected (n.d.) −5.98 and n.d. −20.2 μg/g of 16 PAHs, in the particulate and gas phases, respectively, are determined from the emission of liquid crystal waste pyrolysis. The PAH profiles showed a predominance of naphthalene (42.6%) and phenanthrene (13.5%). The total PAH emissions for the 16 species were 7.75 and 44.05 μg/g in the particulate and gas phases, respectively, significantly lower than the values associated with liquid crystal combustion. From the viewpoint of PAH emission control, our results suggest that the pyrolysis is a better option for the disposal of liquid crystal wastes than that of combustion.     

A label‐based information flow control model for object‐oriented systems

Abstract

This paper proposes a label‐based information flow control model to prevent information leakage within object‐oriented systems. It offers the features of: (a) adapting to dynamic object state change, (b) adapting to dynamic role change, (c) preventing indirect information leakage, (d) detailing the control granularity to variables, (e) allowing purpose‐oriented method invocation, (f) controlling method invocation through argument sensitivity, (g) allowing declassification, and (h) allowing only trusted sources to write a variable.     

Construction rescheduling based on a manufacturing rescheduling framework

Changes during project execution frequently require schedule updating and rescheduling. However, few studies have discussed rescheduling issues or implemented rescheduling solutions for construction projects. This study investigates resource-constrained construction rescheduling issues using concepts associated with manufacturing rescheduling. Based on an initial schedule and actual progress, a novel rescheduling optimization model using Constraint Programming (CP) techniques is developed to reschedule projects. Two rescheduling methods: (1) complete regeneration (CR); and, (2) partial rescheduling (PR) while minimizing overall project variation are implemented in the proposed model to demonstrate the model capability and applications. PR requiring additional treatments to decrease overall project variation is performed using a novel constraint-release mechanism. Finally, using a case study, optimization results obtained using two rescheduling methods are analyzed and discussed.     

Novel impacts of glycol-modified poly(ethylene terephthalate)(PETG) to crystallization behavior of polyethylene naphthalate (PEN) within stretched miscible blends

For studied blends of amorphous glycol-modified poly(ethylene terephthalate) (PETG) and semicrystalline polyethylene naphthalate (PEN), melt miscibility is understood from the linear variation of a single glass transition temperature (T_g) over the entire composition range. The diluent effect of PETG component severely retarded the crystallization of PEN component within blends. Nevertheless, after being through isothermal stretching at 120 °C, crystallization was able to progress efficiently during heating in a continuous manner. Instead of being thermally relaxed back to amorphous state, parallel sliding motions of stretched PEN segments toward crystallization appear rather dominant. Within stretched blends, the PETG content emerged as a critical factor to the crystallinity increase of PEN fraction and the absence of lattice defect, instead of behaving as a diluent component. Furthermore, as being indicated by in-situ small-angle X-ray experiments, regular lamellar stacking gradually developed within stretched blends through heating, which indicates the involvement of thermally activated self-association of randomly distributed crystalline lamellae. With including a higher fraction of PETG component, these secondary ordering processes including lamellar thickening can be activated at lower temperature. Hence, the accompanied thermal relaxation of flexible PETG segment is inferred able to lubricate the sliding of stretched PEN segments in amorphous regions via lowering encountered frictional hindrance, and thus enhance both primary and secondary ordering processes within stretched blends.     

Computational models and experimental investigations of effects of balance and symmetry on the aesthetics of text-overlaid images

This article describes computational models based on principles of visual weights to compute the symmetry and balance of text-overlaid images. Two experiments were conducted to investigate the effects of symmetry and balance on the aesthetic appeal of text-overlaid images. In the first experiment, five color photos were used to compose a set of test images overlaid with a paragraph of Chinese texts as the stimuli. Contrastly, the second experiment applied monochrome photos to compute the stimuli. The positions of the text overlay were determined by varying the balance and symmetry in order to validate computational aesthetic quantification algorithms with subjective ratings. The stimuli were rated by 20 subjects in each experiment using the ratio-scale magnitude estimation method against a benchmark image for each photo. Results from both experiments show that subjects are adept at judging symmetry and balance in both the horizontal and vertical directions. Subjects are also adept at judging radial symmetry about the center point of an image. The experiments also established a relationship between a higher averaged visual balance and the aesthetic appeal of text-overlaid images. Symmetry in either direction, however, did not result in any proportional relations to the aesthetic appeal.     

Interfacial Reactions and Microstructures of Sn-0.7Cu-<Emphasis Type="Italic">x</Emphasis>Zn Solders with Ni-P UBM During Thermal Aging

The effects of the addition of Zn to Sn-0.7Cu solders are investigated. The study is focused on the interfacial reactions, microstructures, and mechanical properties after reaction with Ni-P under bump metallurgies (UBMs). The Zn contents in Sn-0.7Cu-xZn are varied as 0.2, 0.4, and 0.8 (in wt.% unless otherwise specified). In the reaction with Ni-P UBM during thermal aging at 150°C for 1000 h, (Cu,Ni)₆Sn₅ intermetallic compounds (IMCs) are formed at the Sn-0.7Cu/UBM interface, whereas Zn is incorporated into IMCs to form (Cu,Ni,Zn)₆Sn₅ in the Zn-doped solders. As the Zn content increases, the interfacial IMC thickness is reduced. A total reduction of about 40% in IMC thickness was observed for the 0.8% Zn-doped Sn-Cu. The same IMC particles are also observed in the matrix of each solder. In Sn-0.7Cu, (Cu,Ni)₆Sn₅ particles are coarsened during aging, while (Cu,Ni,Zn)₆Sn₅ particles in the Zn-added solders are less coarsened and remain much smaller than (Cu,Ni)₆Sn₅. The growth rate of (Cu,Ni)₆Sn₅ during thermal aging is significantly suppressed by the addition of Zn. Consequently, after reaction with Ni-P UBM, the Zn-doped solders exhibit a thermally stable microstructure as measured by hardness and shear strength.     

Synthesis,characterization and field emission of single wall carbon nanotubes

In this work, high-quality SWCNTs were synthesized by pyrolysis of ethanol at 900 °C in a tubular furnace. The catalyst was manufactured by depositing Fe and Mo metal on the surface of sol–gel MgO nanopowder. The SWCNTs produced by sol–gel MgO nanopowder have better yield, higher purity, and smaller diameters than those produced by commercial milling MgO powder. The lengths of SWCNTs are up to several microns with diameters in the range of 0.73–1.40 nm. The extremely small turn-on field E_to (0.01 V/μm) and threshold field E_th (0.07 V/μm) show that the SWCNTs have potential applications in field emission displays (FEDs).     

Plasma-enhanced chemical vapor deposition carbon nanotubes for ethanol gas sensors

Carbon nanotubes (CNTs) have been fabricated by microwave plasma-enhanced chemical vapor deposition for detecting the presence of ethanol vapor. The conductance of the CNTs decreases when the sensors are successively exposed to ethanol vapor at room temperature. The surface of the CNTs was modified in oxygen plasma to elevate the detection sensitivity for ethanol. Successful utilization of CNTs in gas sensors may open a new window for the development of novel nanostructure gas devices.