4,4′-Bipyridine–dimethyl­glyoxime (1/1)

In the title compound, C10H8N2·C4H8N2O2, both the dimethyl­glyoxime and the 4,4′-bipyridine mol­ecules have crystallographic C i symmetry. The mol­ecules stack along the a-axis direction with a dihedral angle of 20.4 (8)° between their planes. In the crystal, the components are linked by O—H⋯N hydrogen bonds into alternating chains along [120] and [10]

Polyphenols and extracts from Zingiber roseum (Roxb.) Roscoe leaf mitigate pain, inflammation and pyrexia by inhibiting cyclooxygenase-2: an in vivo and in silico studies

Zingiber roseum (Roxb.) Roscoe, a perennial herb from the Zingiberaceae family, has a long history of traditional use in the treatment of several ailments including pain, inflammation, fever, cough, arthritis, skin diseases, and liver infections. This study sought to confirm the efficacy of Zingiber roseum (Roxb.) Roscoe leaves methanol extract (ZrlME) as reported in traditional usage by evaluating its analgesic, anti-inflammatory, and antipyretic capabilities. In addition, in silico molecular docking of the metabolites identified in ZrlME was studied to verify the experimental outcomes. ZrlME demonstrated strong dose-dependent analgesic efficacy against all analgesic tests. ZrlME (400 mg/kg) showed higher anti-inflammatory activity than the standard in the carrageenan-induced paw edema test model. A significant reduction of rectal temperature (3.97°F↓) was also recorded at the same dose of ZrLME after 24 h of treatment. Seven polyphenolic metabolites were identified and quantified by HPLC-DAD analysis, including 3, 4- dihydroxy benzoic acid, (-) epicatechin, rutin hydrate, p-coumaric acid, trans-ferulic acid, rosmarinic acid, and myricetin. Strong binding affinities (ranges from −5.8 to −8.5 Kcal/mol) between the aforesaid polyphenols and cyclooxygenase-2 were discovered. Moreover, molecular dynamics simulations (MDS) demonstrated that these polyphenols exhibit significant COX-2 inhibitory activity due to their high stability in the COX-2 active site. In computational prediction, the polyphenols were also found to be nontoxic, and a variety of biological activities, such as antioxidant, analgesic, anti-inflammatory, antipyretic, and hepatoprotective, were observed. The results of this study revealed that ZrlME possesses notable analgesic, anti-inflammatory, and antipyretic properties

Ultrathin polarization-insensitive tri-band THz perfect metamaterial absorber

In this paper, an ultrathin and polarization-insensitive THz perfect metamaterial absorber (PMA) was proposed using the traditional sandwiched structure with circular patch resonators on the top layer. The simulated spectrum shows that the proposed PMA has three distinctive absorption peaks at f1 = 0.8 THz, f2 = 2.28 THz and f3 = 3.62 THz, with absorbance of 96.7%, 97.9% and 99.8%, respectively. The electric field distributions of the PMA reveal that the absorption mainly originates from the standing wave resonances between the top and bottom layers. The proposed PMA is polarization insensitive due to its axisymmetric unit cell structure. By adjusting the structure parameters, the resonance frequency, intensity and Q-factor of absorption peak can be tuned effectively. Our design may find potential applications in THz imaging, sensing and signal detection

Green tea catechin prevents oxidative stress-regulated autophagy and apoptosis signaling, and inhibits tenderness in postmortem bovine longissimus thoracis et lumborum muscle

Although green tea catechin has been reported to be an antioxidant and preservative in meat, the extent to which it affects the tenderization of bovine muscle remains largely unknown. This study seeks to evaluate the effect of catechin on the interplay between apoptosis and autophagy, and subsequently, the development of bovine muscle tenderness. The results indicate that catechin significantly alleviated oxidative stress. A concomitant reduction of autophagic markers LC3-II/LC3-I ratio, Beclin-1, and Atg7 levels were caused by catechin. Besides, aforementioned autophagy inhibition was further augmented by PI3K/Akt/mTOR activation. Additionally, catechin protected against mitochondrial dysfunction and inhibited mitochondria-dependent caspase apoptosis pathway. Furthermore, there was a reciprocal inhibition between autophagy and apoptosis. Ultimately, tenderness at 24 and 120 h, an increase in the gap between muscle fiber bundles, and disintegration of myofibrillar architectures were all inhibited by catechin. Therefore, despite alleviating oxidative stress, catechin may hamper tenderization pattern of postmortem bovine muscle

A Cu2+-Selective Probe Based on Phenanthro-Imidazole Derivative

A novel fluorescent Probe 1, based on phenanthro-imidazole has been developed as an efficient chemosensor for the trace detection of copper ions (Cu2+). Probe 1 demonstrated sensitive fluorescence quenching upon binding with Cu2+ through 1:1 stoichiometric chelation. The detection limit for Cu2+ ions was projected through linear quenching fitting to be as low as 2.77 × 10−8 M (or 1.77 ppb). The sensing response was highly selective towards Cu2+ with minimal influence from other common metal ions, facilitating the practical application of Probe 1 in trace detection

Status and factors influencing on-farm conservation of Kam Sweet Rice (Oryza sativa L.) genetic resources in southeast Guizhou Province, China

Abstract Background Kam Sweet Rice (KSR) is a special kind of rice landrace that has been cultivated for thousands of years in the borders of Guizhou, Hunan, and Guangxi Provinces of China, and is mainly distributed in southeast Guizhou Province of China currently. KSR has many unique qualities, including strong resistance to diseases, pests, and adverse abiotic conditions, difficulty of threshing, and well glutinous features. KSR germplasm resources are an indispensable material and cultural symbol in the production and daily life and customs of the Dong people. Related studies showed that numerous traditional KSR varieties and cultivation area of KSR decreased sharply from the Qing dynasty to 2015, but many KSR varieties are still conserved in Dong villages of southeast Guizhou Province compared to other areas. However, the number of KSR varieties that are conserved on farms in southeast Guizhou Province and factors influencing the erosion and conservation of KSR genetic resources is unclear. Therefore, this study was an on-farm conservation investigation of KSR genetic resource in China’s major KSR producing areas—Liping, Congjiang, and Rongjiang counties in Guizhou Province and influencing factors analysis of KSR abandonment and conservation. Methods The information of KSR conservation status and variety characteristics, typical villages, Dong’s cultural customs, and factors influencing KSR abandonment and conservation was obtained using ethno-biology methods, mainly through field research interviews, including participatory observation, semi-structured interviews, key informant interviews, focus group discussions, and cultural anthropology. The altitude, plant height, awn color and length, hull color, and rice color of 156 KSR accessions in 28 villages were recorded. The variety quantity and cultivation area of KSR were investigated in 33 ethnic villages. Questionnaire surveys were conducted in typical Dong villages to obtain local farmers’ attitudes toward cultivation and protection of KSR. We randomly selected 26 farmers from Sizhai village and 30 farmers from Huanggang village and chose 3 social characteristics including age, gender, and education levels of farmers, and adopted the method of face-to-face interviewing to complete the questionnaires. Then, we analyzed the correlation and determined the significance between farmers with different social characteristics and farmers’ attitudes to KSR development and protection using SPSS 17.0 software. Results (1) On-farm conservation status of KSR: a total of 156 KSR varieties were collected from 28 ethnic minority villages from 13 townships (accounting for 21% of three counties) in Liping, Congjiang, and Rongjiang counties. KSR accessions accounted for more than 90% of local rice varieties in each village. According to local farmers, although the quantity of KSR varieties decreased more than 50% in the investigated villages compared to the past 10–20 years, some Dong villages have still cultivated KSR, accounting for more than 50% of the rice field area in 10 villages. This result showed that many KSR varieties are still conserved by in Dong villages, and these KSR varieties have a high genetic diversity of phenotypes. (2) Typical villages investigation: the cultivation area of KSR in Congjiang was the highest, 6.7 times larger than Liping and eight times larger than Rongjiang. In addition, the cultivation area of KSR in Dong villages was larger than that in other ethnic villages, and villages that had a higher planting area of KSR had more KSR accessions. (3) Farmers’ attitude toward the development and conservation of KSR: Dong farmers hold the negative attitudes concerning the development of KSR resources, but they thought it is necessary to protect KSR landraces. Especially, a high level of education and female, young, and old farmers played more important roles in the cultivation and protection of KSR. Conclusions Until now, some Dong ethnic villages have still cultivated KSR for thousands of years in Qiandongnan area, although the number of varieties and the planting area of KSR have been greatly reduced. In addition, ethnic traditional culture and social customs were the main influencing factors of KSR conservation; economic, management, and policy factors were the main influencing factors of KSR abandonment. Through the analysis of the correlation between farmers with different social characteristics and their attitudes toward the cultivation, reasons for conservation and abandonment, development tendency, and protection of KSR, we found that a high level of education and female, young, and old farmers play more important role in the cultivation and protection of KSR. Therefore, in order to promote the protection and sustainable utilization of KSR, it is necessary to build on-farm conservation of KSR and improve the position of female farmers and the education level of young people, and encourage the old people to educate the middle-aged to conserve and protect KSR as well as Dong’s traditional culture and social customs. This study is of great significance to promote better protection and optimal utilization of KSR and enable the public, government, and related researchers pay more attention to conserving ethnic traditional cultures

A Novel Synthesizing Strategy of 3D Cose₂ Porous Hollow Flowers for High Performance Lithium–Sulfur Batteries

Redox kinetics of lithium polysulfides (LiPSs) conversion and poor electrical conductivity of sulfur during the charge-discharge process greatly inhibit the commercialization of high-performance lithium–sulfur (Li–S) batteries. Herein, we synthesized CoSe2 porous hollow flowers (CoSe2-PHF) by etching and further selenizing layered double hydroxide, which combined the high catalytic activity of transition metal compound and high electrical conductivity of selenium. The obtained CoSe2-PHF can efficiently accelerate the catalytic conversion of LiPSs, expedite the electron transport, and improve utilization of active sulfur during the charge-discharge process. As a result, with CoSe2-PHF/S-based cathodes, the Li–S batteries exhibited a reversible specific capacity of 955.8 mAh g−1 at 0.1 C and 766.0 mAh g−1 at 0.5 C, along with a relatively small capacity decay rate of 0.070% per cycle within 400 cycles at 1 C. Even at the high rate of 3 C, the specific capacity of 542.9 mAh g−1can be maintained. This work enriches the way to prepare porous composites with high catalytic activity and electrical conductivity as sulfur hosts for high-rate, long-cycle rechargeable Li–S batteries

Effects of Traditional Ethnic Minority Food Culture on Genetic Diversity in Rice Landraces in Guizhou Province, China

Ethnic minorities living in Guizhou Province, China, have produced numerous rice landraces that are rich in genetic variations. Studying the genetic diversity and population structure of rice landraces in Guizhou has therefore become a topic of great research interest. However, the influence of ethnic minorities and their traditional food cultures on rice landraces remains unclear. We analyzed the genetic diversity of 598 rice landraces using simple sequence repeat (SSR) markers. Furthermore, we analyzed the nucleotide variations between two similar populations collected during two different time periods using a single-nucleotide polymorphism (SNP) haplotype analysis of six unlinked nuclear loci. The three major results were as follows: (1) The genetic diversity index of rice landraces in six ecologically distinct rice farming zones of Guizhou Province was high (He = 0.7721), and Southwest Guizhou, which has a large population of ethnic minorities, is the center of genetic diversity of rice landraces in the province; this region had the highest He at 0.7823 and the highest polymorphic information content (PIC) at 0.7562. (2) A neighbor-joining (NJ) phylogenetic tree and a model of the population structure showed that the rice landraces from the southwest, south, and southeast of Guizhou had unique genetic structures and genetic backgrounds, which are closely related to the traditional diet cultures of the local ethnic minorities. (3) A nucleotide variation analysis of similar rice landraces collected in 1980 and 2015 revealed that, after 35 years of domestication by ethnic minorities, the original dominant haplotypes were well-preserved; the frequency of the most favorable haplotypes gradually increased to adapt to the traditional food culture. This study is expected to promote the protection and sustainable utilization of rice landraces from this unique region and to provide valuable germplasm materials and information for future rice breeding and basic research efforts

A Ratiometric Fluorescent Sensor for Cd2+ Based on Internal Charge Transfer

This work reports on a novel fluorescent sensor 1 for Cd2+ ion based on the fluorophore of tetramethyl substituted bis(difluoroboron)-1,2-bis[(1H-pyrrol-2-yl)methylene]hydrazine (Me4BOPHY), which is modified with an electron donor moiety of N,N-bis(pyridin-2-ylmethyl)benzenamine. Sensor 1 has absorption and emission in visible region, at 550 nm and 675 nm, respectively. The long wavelength spectral response makes it easier to fabricate the fluorescence detector. The sensor mechanism is based on the tunable internal charge transfer (ICT) transition of molecule 1. Binding of Cd2+ ion quenches the ICT transition, but turns on the π − π transition of the fluorophore, thus enabling ratiometric fluorescence sensing. The limit of detection (LOD) was projected down to 0.77 ppb, which is far below the safety value (3 ppb) set for drinking water by World Health Organization. The sensor also demonstrates a high selectivity towards Cd2+ in comparison to other interferent metal ions