Near-infrared Fourier transform Raman (FT-Raman) spectroscopy was employed to study the molecular structure of edible zein films/coatings, which were fabricated directly from zein protein. The secondary structure of zein protein was mainly in alpha-helix and remained unaltered during film formation as evidenced by the vibrational modes of amide I at 1656 cm(-1) and amide III at 1274 cm(-1). Raman results indicated that hydrophobic interaction played an important role in the formation of zein film and disulfide bonding might be responsible for the structural stability of zein protein during film formation. To enhance its antimicrobial property, an antimicrobial zein film was manufactured by incorporating zein protein with benzoic acid whose structure was then characterized by FT-Raman. It showed that physical entrapment or hydrophobic interaction was crucial to the incorporation of benzoic acid with zein protein, and the secondary structure of the antimicrobial film was still maintained in alpha-helical form. In addition, FT-Raman exhibits its preference in directly determining the thickness of zein films/coatings. By correlating the Raman intensity ratio of nu(1003) to nu(84) (I(1003/84)) versus the thickness of zein film, a linear relationship with high coefficient (R(2) = 0.9927) was obtained, which was then used pragmatically to determine the thickness of zein coatings on apple. It showed that the FT-Raman result (thickness = 0.27 +/- 0.01 mm) was consistent with that of classical micrometric measurement (thickness = 0.28 +/- 0.02 mm). Consequently, FT-Raman provides a direct, simple, and reagent-free method to characterize the structure and the thickness of zein films/coatings.

A series of in-frame deletion mutants was used to identify a domain within the 3a protein of cucumber mosaic virus (CMV) that is required for RNA-binding activity. Deletions in the 3a gene were generated by PCR and restriction digestion, and the resulting mutated 3a sequences were cloned either in pT7-7 or in pGEX-5X3 expression vectors. The mutated 3a proteins or fusions with glutathione S-transferase (GST) were expressed in E. coli, purified, and their nucleic acid-binding activities analysed by photochemical UV cross-linking assays using digoxigenin-UTP-labelled RNA probes. Comparative analyses of seven mutated 3a proteins obtained from inclusion bodies and eight GST fusion proteins revealed that there is an RNA-binding domain located between amino acids 174 and 233. This RNA-binding domain is able to bind single-stranded RNA out of the context of the complete 3a movement protein and is highly conserved within both subgroups of CMV.

Fourier transform (FT)-Raman spectroscopy was employed to study the molecular structure of yam proteins isolated from three commonly consumed yam species including Dioscorea alata L., D. alata L. var. purpurea, and Dioscorea japonica. Although D. alata L. and D. alata L. var. purpurea consisted of similar amino acid residues, they still exhibited significant differences in conformational arrangement. The secondary structure of D. alata L. was mainly an alpha-helix, while D. alata L. var. purpurea was mostly in antiparallel beta-sheets. In contrast, D. japonica, which belongs to a different species, exhibited explicit differences in amino acid compositions and molecular structures of which the conformation was a mixed form of alpha-helices and antiparallel beta-sheets. FT-Raman directly proved the existence of S-S in yam proteins, implying that oligomer formation in yam proteins might be due to disulfide linking of dioscorin (32 kDa). The microenvironment of aromatic amino acids and the state of S-S in yam proteins were also discussed.

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Structural globalization has been both a cycle and an upward trend as periods of greater global integration have been followed by periods of deglobalization on a long-term stair-step toward the greater connectedness of humanity. Since 2008, the world-system may once again be entering another phase of structural deglobalization as the contradictions of capitalist neoliberalism, environmental degradation and uneven development have provoked different kinds of anti-globalization populism, rivalry among contending powers, trade wars and policies and social movements intended to mitigate the effects of anthropogenic climate change. This plateauing and possible downturn in economic connectedness is occurring in the context of U.S. hegemonic decline and the emergence of a more multipolar configuration of economic and political power among states. The combination of greater communications connectivity and greater awareness of North/South inequalities, as well as destabilizing conflicts and climate change, have provoked waves of refugee migrations and political reactions against immigrants. The result has been a period of chaos that is similar in some ways (but different in others) from what occurred during the last half of the 19th century and the first half of the 20th century. This study investigates the question of whether the world-system is indeed once again entering another period of economic deglobalization and compares the current period with what happened in the 19th and 20th centuries to specify the similarities and the differences. We conclude that, based on changes in the level of economic connectedness since 2008, it is still too soon to tell for sure if the world-system is entering another period of deglobalization, but the important similarities between the recent period and earlier periods of deglobalization make it likely that the system is now in another deglobalization or plateau phase.