RESUMO
Eggs that have been hard-boiled are frequently used as ready-to-eat food. Refrigerated and frozen storage of hard-boiled eggs causes issues, such as customer rejection owing to textural changes. The objective of this research is to ascertain how storage temperature affects hard-boiled eggs' alteration in texture over time. Medium-sized brown shell eggs were acquired from a local market, boiled at 100°C for 15 min, and then stored at room temperature (25°C), refrigeration (4°C), and freezing (-18°C) conditions for 0, 12, 24, and 48 h. Fourier transform infrared spectroscopy (FTIR), texture profile, visual observation using a gemological microscope, free amino acid content, and color were measured. Freezing had a substantial impact on the eggs' hardness, gumminess, chewiness, and cohesiveness (p<0.05). The FTIR spectrums confirmed the textural changes in bonds of amide A (3,271 cm-1), amide I (1,626.2 cm-1), amide II (1,539.0 cm-1), C=O stretch of COO- (1,397 cm-1), asymmetric PO2- stretch (1,240 cm-1). Microscopic images confirmed structural changes in eggs stored at -18°C. The free amino acid content was lower in fresh and frozen eggs than in the rest (p<0.05). However, there was no discernible variation in the egg white's color when eggs were kept at 4°C (p>0.05). Salmonella spp. was found exclusively in eggs kept at room temperature. In conclusion, hard-boiled eggs did not exhibit structural or chemical changes when stored at 4°C for up to 48 h compared to freezing and room temperature conditions.
RESUMO
Carthamus tinctorius L. (safflower), an economic crop and herb, has been extensively studied for its diverse chemical constituents and pharmacological effects, but the mechanism of safflower pigments (SP) leading to different colors of florets has not been clarified. In the present study, we compared the contents of SP in two varieties of safflower with white and red florets, named Xinhonghua No. 7 (WXHH) and Yunhong No. 2 (RYH). The results showed the contents of SP in RYH were higher than WXHH. To investigate genes related to SP, we obtained six cDNA libraries of florets from the two varieties by transcriptome sequencing. A total of 225,008 unigenes were assembled and 40 unigenes related to safflower pigment biosynthesis were annotated, including 7 unigenes of phenylalanine ammonia-lyase (PAL), 20 unigenes of 4-coumarate-CoA ligase (4CL), 1 unigene of trans-cinnamate 4-monooxygenase (C4H), 7 unigenes of chalcone synthase (CHS), 4 unigenes of chalcone isomerase (CHI), and 1 unigene of flavanone 3-hydroxylase (F3H). Based on expression levels we selected 16 differentially expressed unigenes (DEGs) and tested them using reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR), which was consistent with the sequencing results. Consequently, we speculated that in WXHH, 3 PALs, 3 4CLs, 1 C4H, 1 CHS, and 1 CHI, which were down-regulated, and 1 F3H, which was up-regulated, may play a key role in the formation of white florets.
RESUMO
White light-emitting diodes (LEDs) are becoming an alternative general light source, with huge energy savings compared to conventional lighting. However, white LEDs using phosphor(s) suffer from unavoidable Stokes energy converting losses, higher manufacturing cost, and reduced thermal stability. Here, we demonstrate electrically driven, phosphor-free, white LEDs based on three-dimensional gallium nitride structures with double concentric truncated hexagonal pyramids. The electroluminescence spectra are stable with varying current. The origin of the emission wavelength is studied by cathodoluminescence and high-angle annular dark field scanning transmission electron microscopy experiments. Spatial variation of the carrier injection efficiency is also investigated by a comparative analysis between spatially resolved photoluminescence and electroluminescence.
RESUMO
Our patient presented with leukonychia totalis at the age of 15 years. Other malformations such as syndromes or underlying internal diseases did not exist. The patient's family history was unremarkable. In the classification of leukonychias, the real, usually hereditary leukonychia can be distinguished from the acquired form. The white color of the nails can be isolated, depending on its present form, appear as part of a syndrome, or as a result of internal disease. An effective treatment of hereditary leukonychia is not known.