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This experimental ekphrastic essay meditates on the history of eighteenth-and nineteenth-century rice plantation slavery from the ecocritical perspective of the bobolink, or rice bird. The vignettes of a postbellum image of a Georgia plantation reveal the many facets of this avian migrant’s entanglement with Indigenous histories of wild rice and with Black labour and performance. Weaving in contemporary art and music, this essay explores how a prized songbird—and agricultural pest—developed its grain diet and flight patterns in tandem with the growth of plantation capitalism across the Americas and the Atlantic world.

His/His motif is crucial to CuII binding of multi-His-containing metal sites in proteins and peptides, and thus receives much research attention. However, how CuII -His/His interactions are affected by molecular dynamic context remains elusive. Herein a study of heterogeneity in CuII-His/His interactions is demonstrated using a synthetic ethylenediaminetetraacetate (EDTA)-based glycinamide-type N, O-ligand, namely, EDTA-bis(L-histidine methyl ester) (P), complemented by its analog EDTA-bis(histamine) (P'). CuII binding feature was dissected by means of electrospray ionization-high resolution mass spectrometry (ESI-HRMS) which established a simultaneous formation and coexistence of mono-CuII (1), di-CuII (2) and decarboxylated di-CuII complex (3). Comprehensive ESI-HRMS titration revealed metal-concentration-dependent interaction modes, pH-dependence in ligating-group competition and cooperation, and substituent effect on the consecutive CuII binding. Further, ESI-HRMS allowed the associated innate proton affinity (pKa ~6.46 [1 + H+], 7.82 [2 + H+], and 8.77 [3 + H+], and Na+ (K+) uptaking ability of the Cu-complexes to be determined to substantiate the above putative structural elucidation. In parallel, external-ligand (Tris, PO42-) competition experiments permitted capturing and distinguishing between the two types of di-nuclear coordination modes (anti-Cu/Cu independent vs syn-Cu/Cu mutual-dependent modes) pertaining to the di-CuII-centers in 2 and 3, respectively; the latter being Cu/Cu inter-dependent di-Cu complex, which apparently resisted external-ligand capturing, was conceivably resulted from decarboxylation of the accompanying syn-isomer of 2 (anti). Moreover, circular dichroism (CD) titration enabled an estimation that the first CuII-binding is three-fold stronger than the second CuII at neutral and basic pH, but nearly similar to the second CuII at acidic pH. Furthermore, 13C NMR assisted in illuminating that both amidate and Im groups strongly participated in CuII binding at pH 7.10. Consequently, a two-dimensional landscape (variation of pH and CuII concentration) for binding was suggested, and from which an internally non-static binding mode in the mono-CuII complex (1) was extracted to account for a dynamic transition from mono-CuII to two types of di-CuII species, due to carboxylate-group scrambling on CuII ions together with backbone Δ-Λ conformation change. It is concluded that the pH-dependent on-off Im-CuII, amidate-CuII, carboxylate-CuII, amide oxo-CuII and amino-CuII binding and backbone dynamics act synergistically in the mono- vs di-CuII binding.

A polymer-based hole-transporting layer (HTL) with a tunable work function and highest occupied molecular orbital (HOMO) position was demonstrated to effectively optimize the anode junctions of optoelectronic devices. Herein, the perfluorinated ionomer (PFI) was utilized to realize the synthesis of a well-dispersed poly(3,4-ethylene dioxythiophene) (PEDOT) colloid solution, which could be subsequently cast into an efficient HTL. According to the time-of-flight secondary-ion mass spectroscopy and ultraviolet photoelectron spectroscopy analysis, a uniform, interpenetrating PEDOT network with a deep-lying HOMO position could be obtained in the PEDOT:PFI layer. For solar cells, since a deep-lying HOMO position of the HTL was favorable for minimizing the hole injection barrier, a superior organic photovoltaic efficiency of 15.1% and a perovskite solar cell efficiency of 17.8% were achieved. As for organic photodetectors, a deep-lying HOMO position of the HTL was able to reduce the dark current density (JD) by blocking the leakage current under a reverse bias. Utilizing the PEDOT:PFI with an optimized PFI content, an extremely low JD of 6.2 nA cm−2 with an external quantum efficiency of 67% at 1000 nm wavelength was achieved, which sets a benchmark for the emerging near infrared sensing technologies.

Insect-induced galls are an atypical growth and differentiation form of plant tissue. The objective of this research was to study the expression of photosynthesis-associated proteins in Cecidomyiidae galls derived from the leaves of Litsea acuminata using a Western blot analysis of antibodies against light-harvesting complex (LHC) proteins isolated from non-galled and galled leaves and gall tissues. These LHC proteins involved in RC-1a, RC-1b, LHCb4, LHCb5, CP47, and CP-1a showed different responses in galls and leaves and exhibited a remarkable potential modulation role in regulating gall development. All photosynthetic proteins were repressed in gall tissues, indicating that light reaction functioning was significantly repressed. Compared to non-galled and galled leaves, galls demonstrated significantly lower chlorophyll (Chl) content and photosystem II maximum quantum efficiency (Fv/Fm) values, suggesting that insect infestations reduced photosynthetic efficiency. In addition, there were significant and positive correlations between LHCb5, CP-1a, and CP47 vs. Fv/Fm values and Chl content in galls and leaves, indicating that gall infections induced physiological changes, and therefore, that the Fv/Fm value could be utilized as a tool to easily and quickly study the eco-physiology of galls.

The aim of the present study was to investigate the photosynthetic properties and transcriptomic profiles of wildtype and chlorophyll (Chl) b-lacking rice (Oryza sativa L.). The plastid ultrastructure of the Chl b-lacking rice (i.e., loss of starch granules, abundant vesicles, and abundant plastoglobuli) indicated abnormal plastid development, whereas the analysis of transcriptome profiles and differentially expressed genes revealed that gene encoding PsbR (PSII core protein) was downregulated in the mutant, thereby reducing the Chl accumulation of the mutant. Meanwhile, in regards to Chl biosynthesis and degradation pathways, GluTR gene was downregulated, whereas UROD, CPOX, and MgCH genes were upregulated. The qPCR results were generally consistent with those of the transcription analysis, except for the finding that NOL genes, which regulate Chl b degradation, were upregulated. These results suggest that both the reduction in Chl accumulation and increase in conversion rate of Chl b to Chl a caused Chl a/b ratio amplification in mutant. The present study also provides evidence for Chl b degradation via pheophorbide b.

The objective of this research was to study altered distributions of chloroplasts in cecidomyiid galls derived from the leaves of Machilus thunbergii Sieb. & Zucc. and Litsea acuminata (Blume) Kurata using confocal laser-scanning microscopy and transmittance spectra. Chloroplasts in all gall tissues gradually decreased in the direction from the exterior toward the inside larval chamber based on Integrated Optical Density (IOD) and absorptivity indices, and chloroplast distributions in various gall tissues were species-specific. Different species of herbivorous insect dramatically altered chloroplasts in their host leaves. The spectral index was significantly and positively correlated with the IOD, and therefore, the transmittance spectra could be utilized as a tool to easily and quickly study the ecophysiology of galls.

Terpios hoshinota is an aggressive, space-competing sponge that kills various stony corals. Outbreaks of this species have led to intense damage to coral reefs in many locations. Here, the first large-scale 16S rRNA gene survey across three oceans revealed that bacteria related to the taxa Prochloron, Endozoicomonas, SAR116, Ruegeria, and unclassified Proteobacteria were prevalent in T. hoshinota. A Prochloron-related bacterium was the most dominant and prevalent cyanobacterium in T. hoshinota. The complete genome of this uncultivated cyanobacterium and pigment analysis demonstrated that it has phycobiliproteins and lacks chlorophyll b, which is inconsistent with the definition of Prochloron. Furthermore, the cyanobacterium was phylogenetically distinct from Prochloron, strongly suggesting that it should be a sister taxon to Prochloron. Therefore, we proposed this symbiotic cyanobacterium as a novel species under the new genus Candidatus Paraprochloron terpiosi. Comparative genomic analyses revealed that 'Paraprochloron' and Prochloron exhibit distinct genomic features and DNA replication machinery. We also characterized the metabolic potentials of 'Paraprochloron terpiosi' in carbon and nitrogen cycling and propose a model for interactions between it and T. hoshinota. This study builds a foundation for the study of the T. hoshinota microbiome and paves the way for better understanding of ecosystems involving this coral-killing sponge.

Extreme temperatures have become a threat to crop yields. To maintain plant growth and yield, chlorophyll (Chl) biosynthesis plays a crucial role in adaptation to temperature stress. This study investigated the influence of temperature on the biosynthesis and characteristics of pigments (Chl a, Chl b, and carotenoids) in the leaves of Chl b-lacking mutant rice (Chlorina 1, ch1) and wild-type rice (Norin No.8, wt). The ch1 showed thinner stacked grana caused by a decrease in thylakoid membranes per granum at 15 °C, whereas the destacked grana were observed at 35 °C after 12 h incubation. However, the grana are stacked normally, along with the absence of Chl b, and a significantly decreased amount of Chl a in both wt and ch1 were observed after heat stress exposure, demonstrating that light-harvesting complex II proteins are involved in grana stacking. Ch1 was sensitive to 15 °C during the first 4 h of incubation but it subsequently adapted to the cold environment. In addition, there were no significant differences in the photosynthesis between wt and ch1 after 12 h incubation at 35 °C. Differentially expressed gene (DEGs) analysis revealed that GluRS expression decreased, which resulted in a decline in Chl biosynthesis in wt and ch1 at 35 °C. At 8 h and 12 h, there were no significant differences in the expression of DEGs involved in Chl biosynthesis and degradation between wt and ch1 at 15 °C. ALAD expression in wt and ch1 at 15 °C decreased until it was undetectable. These findings suggested that ch1 may adapt to temperatures ranging from 15 °C to 35 °C.

Background: Chlorophyllases (Chlases) are housekeeping proteins in plant cells. The dephytylating enzymes can catalyze chlorophyll (Chl) to form chlorophyllide, but the distribution of Chlases in plant cells is still an interesting debate. In this study, antibody of PmCLH2 was made and used by immunogold-labelling technique to detect the location of Chlase of Pachira macrocarpa (Pm) leaves at four developmental stages, including young, mature, yellowing, and senesced stages. Results: The transmission electron microscopy results show that Chlases were comprehensively found in portions of chloroplast, such as the inner membrane of the envelope, grana, and the thylakoid membrane of the chloroplast, cytosol, and vacuoles at young, mature, and yellowing stages of Pm leaves, but not in the cell wall, plasma membrane, mitochondria, and nucleus. Conclusions: PmChlases were mainly detected in vacuoles at the senescent stage, but a few were found in the chloroplasts. A pathway is proposed to explain the birth and death of Chl, Chlase, and chloroplasts in higher plants.

Terpios hoshinota is a ferocious, space-competing sponge that kills a variety of stony corals by overgrowth. Outbreaks of this species have led to intense coral reef damage and declines in living corals on the square kilometer scale in many geographical locations. Our large-scale 16S rRNA gene survey across three oceans revealed that the core microbiome of T. hoshinota included operational taxonomic units (OTUs) related to Prochloron, Endozoicomonas, Pseudospirillum, SAR116, Magnetospira, and Ruegeria. A Prochloron- related OTU was the most dominant cyanobacterium in T. hoshinota in the western Pacific Ocean, South China Sea, and Indian Ocean. The complete metagenome-assembled genome of the Prochloron-related cyanobacterium and our pigment analysis revealed that this bacterium had phycobiliproteins and phycobilins and lacked chlorophyll b, inconsistent with the iconic definition of Prochloron. Furthermore, the phylogenetic analyses based on 16S rRNA genes and 120 single-copy genes demonstrated that the bacterium was phylogenetically distinct to Prochloron, strongly suggesting that it should be a sister taxon to Prochloron; we therefore proposed this symbiotic cyanobacterium as a novel species under a new genus: Candidatus Paraprochloron terpiosii. With the recovery of the complete genome, we characterized the metabolic potentials of the novel cyanobacterium in carbon and nitrogen cycling and proposed a model for the interaction between Ca. Pp. terpiosi LD05 and T. hoshinota. In addition, comparative genomics analysis revealed that Ca. Paraprochloron and Prochloron showed distinct features in transporter systems and DNA replication.ImportanceThe finding that one species predominates cyanobacteria in T. hoshinota from different geographic locations indicates that this sponge and Ca. Pp. terpiosi LD05 share a tight relationship. This study builds the foundation for T. hoshinota’s microbiome and paves a way for understanding the ecosystem, invasion mechanism, and causes of outbreak of this coral-killing sponge. Also, the first Prochloron-related complete genome enables us to study this bacterium with molecular approaches in the future and broadens our knowledge of the evolution of symbiotic cyanobacteria.

Rice (Oryza sativa L.) cultivars ‘Taichung shen 10’ (‘TCS10’) and ‘IR1552’ were hydroponically grown under different light conditions to investigate the effect of light quality on their biomass, transpiration, water-use efficiency (WUE), carbon isotope discrimination (Δ), seed nitrogen (N) contribution and nitrogen uptake ability from the hydroponic nutrient solutions. Light emitting diode (LED) lighting systems were used to control light quality. Different light treatments were applied to the rice seedlings including red (R), green (G), and blue light (B), with red + blue light (RB) as control. The photon flux density was set at 105 μmol m-2 s-1. WUE and Δ were combined to evaluate whole-plant WUE. Improved whole-plant WUE was observed for both cultivars under R and RB light due to lower transpiration rates than under B light. Green light also improved Δ in both rice seedling cultivars. Seed N contribution of both cultivars was stable across all light treatments, while improved N uptake ability was observed under B and RB light. In addition, N uptake in ‘IR1552’ rice seedling cultivars did not respond as favourably to green light as ‘TCS10’ cultivars.

Phalaenopsis (Phal.) orchids including white, yellow, and purple flowers are some of the most important commercial orchids worldwide. These flowering plants can be considered to be promising sources of antioxidants since several medicinal orchids were shown to have potential antioxidant activities. The antioxidant activities and several secondary metabolite compounds of the methanolic extracts of four parts (the root, pedicel, leaf, and flower) of three hybrids of white (Phal. ‘City More’), yellow (Phal. ‘Sogo Meili’), and purple (Phal. ‘Queen Beer’) flowering orchids were investigated. Results showed that the highest levels of chlorophyll a and chlorophyll b were respectively obtained in leaf extracts of white and purple orchids, whereas carotenoid showed the highest content in the flower extract of the yellow orchid. Among all tested extracts, flavonoids and anthocyanin demonstrated the highest levels in the flower extract of the purple orchid, whereas the highest level of polyphenols was observed in the flower extract of the yellow orchid. The leaf extract of the white orchid was the most effective extract with a 50% inhibitory concentration in the DPPH-scavenging activity assay, while the highest ferrous iron-chelating effect was observed in flower extracts of the yellow orchid and purple orchid, and the pedicel extract of the purple orchid. In the reducing power assay, the flower extract of the white orchid showed the most potent extract, followed by the leaf extract of the yellow orchid and the flower extract of the purple orchid. Relationships between flower colors and antioxidant activities of these orchids showed them to be potential sources of antioxidants for both medicinal use and stress-tolerance in these orchids.

Human bioavailability data on chlorophyll (Chl) is very limited. The distribution of Chl-related compounds (CRCs) derived from dietary spinach was investigated in human blood. Eight healthy adults, aged from 21 to 61 year-old, consumed 1.2 kg of just-boiled fresh spinach after an 8-h overnight fast. Before and then 3 h after consuming the spinach, blood samples were taken from each participant. Freeze-dried blood samples were prepared, and 80% acetone was added for grinding. Eight peaks were found in the blood using high-performance liquid chromatography (HPLC), and the main CRCs in the samples were pheophytin (Phe) and pheophorbide (Pho) derivates. Compared to a fasted state, markedly higher levels of blood CRCs were detected in all subjects, except that Pho metabolites were not found in two subjects. No significant differences were seen in most of the peaks between males and females; however, relatively higher CRCs levels were observed in females, particular of Pho derivates. In addition, the blood contained significantly higher levels of Phe in the 36~61-year-old group than in the 21~35-year-old group. These results suggest that the conversion of Chls to CRCs is a rapid process, and Chls obtained by ingestion can be absorbed by the human body.

Chlorophyllase (Chlase) is a hydrophobic enzyme that catalyzes the hydrolysis of chlorophyll (Chl) to chlorophyllide (Chlide) and phytol. The objectives of this research were to study Chlase characteristics of sweet potatoes ( Ipomoea batatas , Ib) with various leaf colors: yellow (CN1927), green (TN57), and purple (CYY8467). Large variations in Chl and anthocyanin (Ant) and carotenoid (Car) existed in all plants, and CYY8467 contained significantly higher Chl, Ant, and Car levels compared to TN57 and CN1927. Various plants exhibited different Chlase activities, and Chl a degradation by Chlase of CYY8467 was higher than those of TN57 and CN1927. Nevertheless, Chlase activity in CN1927 exhibited a higher substrate preference toward Chl b than Chl a . Expression of the Chlase gene was detected in all leaves; however, IbChlase mRNA was most strongly active and regulated in TN57. The open reading frame sequences of IbChlase in TN57, CN1927, and CYY8467 shared 95% identity, and an eight-nucleotide sequence of Chlase in CYY8467 was missing due to a frame-shift mutation of the Chlase gene leading to early termination of gene translation. A phylogenetic analysis of Chlase indicated that 30 plants diverged into three clades, and sequences from TN57 and CN1927 were clustered together in a clade of the Chlase2.

Traditionally, wafer cleaning via the batch type in semiconductor manufacturing has been used for many years. And the single wafer processor has developed for the advantage in particle control by preventing the pollution from accumulated materials. Although single wafer processor can overcome the particle and defect problem in conventional wet station, silicon nitride removal by phosphoric acid still uses the bench type tool even other processes including RCA cleaning has been changed to the single wafer tool in advanced technology. One of the reasons is the selectivity of silicon nitride to oxide. In this work, fundamental studies on the etching rate, uniformity, and selectivity were investigated by a general process tuning knobs in the single wafer processor, such as the rotation speed, puddle time, temperature, etc., which brought us a deeper understanding on the relationship of silicon nitride etching rate to the phosphoric acid.

Photosynthetic properties and transcriptomic profiles of green and white sectors of Ficus microcarpa (c.v. milky stripe fig) leaves were examined in naturally variegated plants. An anatomic analysis indicated that chloroplasts of the white sectors contained a higher abundance of starch granules and lacked stacked thylakoids. Moreover, no photosynthetic rate was detected in the white sectors. Transcriptome profile and differential expressed gene (DEG) analysis showed that genes encoding PSII core proteins were down-regulated in the white sectors. In genes related to chlorophyll metabolism, no DEGs were identified in the biosynthesis pathway of chlorophyll. However, genes encoding the first step of chlorophyll breakdown were up-regulated. The repression of genes involved in N-assimilation suggests that the white sectors were deprived of N. The mutation in the transcription factor mitochondrial transcription termination factor (mTERF) suggests that it induces colorlessness in leaves of the milky stripe fig.

This Introduction argues for the ongoing relevance of “global” to eighteenth-century, postcolonial, and Comparative Literature scholarship. It assesses the development of critical global studies since the 2000s and calls for further linguistic, cultural, and geographic diversity and representation on eighteenth-century academic panels, in particular those sponsored by the Modern Languages Association. The five essays included in this Critical Conversation emerged from a roundtable panel on “Globalizing 18th-century Literary History” organized for the Comparative Literary and Cultural Studies, 18th-Century Forum at the MLA Conference in Austin, 2016. Scholars from the fields of Arabic, Japanese, German, and African studies reflect on the states and stakes of translation, literary, and genre history from non-Anglo perspectives.

The objective of this study was to investigate the dynamics of chlorophyll (Chl), biosynthetic intermediates (protoporphyrin IX, magnesium protoporphyrin IX, and protochlorophyllide), degradation intermediates [chlorophyllide (Chlide), pheophytin (Phe), and pheophorbide (Pho)], and carotenoids (Car) in leaves of rice seedlings. Two rice varieties, ‘Taichung Shen’ 10 (‘TCS10’) and ‘IR1552’, were grown under different light quality conditions controlled by light emitting diodes (LED). Lighting treatments for rice seedlings were included by red (R), blue (B), green (G), and red + blue (RB), with fluorescent lighting (FL) as the control and photosynthetic photon flux density being set at 105 I¼mol m-2 s-1. The results show that lower levels of Chl and Car in leaves were detected under G lighting, and light quality did not mediate porphyrins in biosynthetic pathways. Rice seedling leaves took Chl→Phe→Pho and Chl→Chlide→Pho as the major and minor degradation routes, respectively. Furthermore, higher Phe/Chlide ratios were observed under G and FL lighting conditions, indicating that green-enriched environments can up-regulate the minor degradation route in leaves.Â