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The study aimed to explore the nutritional value of sea buckthorn by-products and the antibacterial effects of their extracts on Escherichia coli. The experiment employed the sodium nitrite-aluminum nitrate method to determine flavonoid content, while alcohol extraction and water extraction methods were used to extract active substances from sea buckthorn by-products. The antibacterial effects of sea buckthorn by-product extracts on Escherichia coli were investigated by the filter paper method, perforation method, and broth dilution method. The results showed that the dry matter (DM) content of sea buckthorn by-products was 97.98%, ash content was 3.41%, crude protein (CP) content was 12.87%, and crude fat (EE) content was 22.48%. With the increase of sea buckthorn by-product addition, gas production showed a decreasing trend. Among alcohol extraction and water extraction methods, the constant broth dilution method exhibited the best antibacterial effect. In the alcohol extraction method, the filter paper method showed good antibacterial effect with an inhibition zone of 14.6 mm. In the water extraction method, the filter paper method did not exhibit a significant inhibition zone, and the perforation method was not significant in both alcohol extraction and water extraction methods. The study suggests that sea buckthorn by-products have rich nutritional value, and alcohol extraction is more effective in inhibiting Escherichia coli compared to water extraction. [ABSTRACT FROM AUTHOR]

Phalaenopsis has a zygomorphic floral structure, including three outer tepals, two lateral inner tepals and a highly modified inner median tepal called labellum or lip; however, the regulation of its organ development remains unelucidated. We generated RNA-seq reads with the Illumina platform for floral organs of the Phalaenopsis wild-type and peloric mutant with a lip-like petal. A total of 43,552 contigs were obtained after de novo assembly. We used differentially expressed gene profiling to compare the transcriptional changes in floral organs for both the wild-type and peloric mutant. Pair-wise comparison of sepals, petals and labellum between peloric mutant and its wild-type revealed 1,838, 758 and 1,147 contigs, respectively, with significant differential expression. PhAGL6a (CUFF.17763), PhAGL6b (CUFF.17763.1), PhMADS1 (CUFF.36625.1), PhMADS4 (CUFF.25909) and PhMADS5 (CUFF.39479.1) were significantly upregulated in the lip-like petal of the peloric mutant. We used real-time PCR analysis of lip-like petals, lip-like sepals and the big lip of peloric mutants to confirm the five genes’ expression patterns. PhAGL6a, PhAGL6b and PhMADS4 were strongly expressed in the labellum and significantly upregulated in lip-like petals and lip-like sepals of peloric-mutant flowers. In addition, PhAGL6b was significantly downregulated in the labellum of the big lip mutant, with no change in expression of PhAGL6a. We provide a comprehensive transcript profile and functional analysis of Phalaenopsis floral organs. PhAGL6a PhAGL6b, and PhMADS4 might play crucial roles in the development of the labellum in Phalaenopsis. Our study provides new insights into how the orchid labellum differs and why the petal or sepal converts to a labellum in Phalaenopsis floral mutants. [ABSTRACT FROM AUTHOR]

Cut flowers of the orchid Oncidium Gower Ramsey are valuable agricultural produce around the world because of their yellow color contributed by carotenoids in adaxial and abaxial epidermal layers in petals and labellum. Here, we investigated the regulation of carotenogenic genes in response to different light qualities in Oncidium flowers. Total chlorophyll content was high in young flower buds and reduced during flower development, but carotenoid content was increased during flower development. We detected 11 key carotenoid biosynthesis genes and determined their expression profiles with light treatment. Real-time PCR revealed high mRNA levels of most genes, except OncCHYB and OncSDR, in vegetative tissues; only OncLCYe showed low expression in flowers. White light upregulated OncPSY, OncLCYb, and OncNCED but downregulated OncPDS, OncZDS, OncCrtISO, OncLCYe, OncCHYB, OncZEP, OncCCD1, and OncSDR; red light upregulated OncPSY, OncLCYb, OncLCYe, and OncCCD1; and UV light upregulated OncPSY, OncPDS, OncLCYb, OncZEP, and OncNCED. We cloned the promoter region of the phytoene synthase gene and found it to have potential cis-regulatory elements, such as TATA-box and CAAT-box, in addition to multiple light-responsive elements such as G-box, I-box, GT-1 motif, GAG-motif, and H-box. Our results of light-regulated carotenogenic gene expression and promoter analysis in flowers of Oncidium Gower Ramsey suggest ways to manipulate carotenoid content for high-quality cut-flower production. [ABSTRACT FROM AUTHOR]

A bathocuproine (BCP) layer is typically used as the hole-blocking layer in p-i-n-structure perovskite solar cells (PSCs) between PC61BM and Ag electrodes. Before evaporating the Ag, we used a low-temperature (<40 °C) atmospheric-pressure dielectric barrier discharge jet (DBDjet) to treat the BCP with different scan rates. The main purpose of this was to change the contact resistance between the BCP layer and the Ag electrodes through surface modification using a DBDjet. The best power conversion efficiency (PCE) of 13.11% was achieved at a DBDjet scan rate of 2 cm/s. The He DBDjet treatment introduced nitrogen to form C−N bonds and create pits on the BCP layer. This deteriorated the interface between the BCP and the follow-up deposited-Ag top electrode. Compared to the device without the plasma treatment on the BCP layer, the He DBDjet treatment on the BCP layer reduced photocurrent hysteresis but deteriorated the fill factor and the efficiency of the PSCs. [ABSTRACT FROM AUTHOR]

For attaining good-performance perovskite solar cells (PSCs), the carrier collection from the perovskite material to the transport layer plays a prominent role; herein, we demonstrate an atmospheric pressure plasma treatment technique to enhance the interface properties between the active perovskite layer and electron transport layer (ETL). A scan-mode low-temperature helium dielectric barrier discharge (DBD) jet is applied to process the TiO2 nanoparticle layers for the flexible n-i-p PSCs made on ITO-coated polyethylene naphthalate substrates. When the surface of TiO2 nanoparticle ETL is treated by the DBD jet at a scan rate of 2 cm sâˆ'1 and scan height of 5 cm by ten times, the photoelectrical conversion efficiency of the cell is enhanced from 12.30% to 13.66%. The performance improvement can be attributed to the increase of hydrophilic Oâ€"C = O functional groups on the surface of the TiO2 nanoparticle layer and the reduction of charge transfer resistance of the cell revealed by x-ray photoelectron spectroscopy and electrochemical impedance spectroscopy, respectively. The results show that the low-temperature DBD jet treatment is a promising technique for processing flexible photovoltaic devices. [ABSTRACT FROM AUTHOR]

Genome-editing techniques such as CRISPR/Cas9 have been widely used in crop functional genomics and improvement. To efficiently deliver the guide RNA and Cas9, most studies still rely on Agrobacterium-mediated transformation, which involves a selection marker gene. However, several limiting factors may impede the efficiency of screening transgene-free genome-edited plants, including the time needed to produce each life cycle, the response to selection reagents, and the labor costs of PCR-based genotyping. To overcome these disadvantages, we developed a simple and high-throughput method based on visual detection of antibiotics-derived H2O2 to verify transgene-free genome-edited plants. In transgenic rice containing hygromycin phosphotransferase (HPT), H2O2 content did not change in the presence of hygromycin B (HyB). In contrast, in transgenic-free rice plants with 10-h HyB treatment, levels of H2O2 and malondialdehyde, indicators of oxidative stress, were elevated. Detection of H2O2 by 3,3′-diaminobenzidine (DAB) staining suggested that H2O2 could be a marker to efficiently distinguish transgenic and non-transgenic plants. Analysis of 24 segregating progenies of an HPT-containing rice plant by RT-PCR and DAB staining verified that DAB staining is a feasible method for detecting transformants and non-transformants. Transgene-free genome-edited plants were faithfully validated by both PCR and the H2O2-based method. Moreover, HyB induced overproduction of H2O2 in leaves of Arabidopsis, maize, tobacco, and tomato, which suggests the potential application of the DAB method for detecting transgenic events containing HPT in a wide range of plant species. Thus, visual detection of DAB provides a simple, cheap, and reliable way to efficiently identify transgene-free genome-edited and HPT-containing transgenic rice. [ABSTRACT FROM AUTHOR]

Background: Haworthia are desert succulents belonging to the Asphodelaceae family. Haworthia species are cultivated commercially as ornamentals and some rare species are quite valuable at retail market but growth slowly and difficult to propagation. However, an efficient micropropagation protocol was remained insufficient. Results: The organogenic cultures obtained from inflorescence explants were cultured on Murashige and Skoog (MS) medium supplemented with various combinations of 6-benzylaminopurine (BA) and α-naphthalene acetic acid (NAA) under a light intensity of 10 μmol m−2 s−1 or 45 μmol m−2 s−1. The highest callus proliferation index (93.15%) with 1.0 mg L−1 BA + 0.1 mg L−1 NAA under a light intensity of 10 μmol m−2 s−1. The best shoot proliferation rates were on media with either 1 mg L−1 BA + 0–0.4 mg L−1 NAA (65.57–81.01%) under a light intensity of 45 μmol m−2 s−1. The highest root length (15.57 mm) and the highest rooting frequency (17 roots per shoot) were obtained when adventitious shoots were inoculated on MS medium with 0.4 mg L−1 NAA + 0.4 mg L−1 IBA. The survival rate of the transplanted plantlets was about 100%. The efficient micropropagation protocol proliferated Haworthia regenerate plants from inflorescence within 11 weeks. Conclusions: The present study determined the best combination of light intensity and plant growth regulators (PGRs) for improved organogenesis of Haworthia during propagation by tissue culture. This optimized protocol showed light intensity is an important factor for efficient callus or shoot regeneration. These results indicate that it will be useful to optimize the light conditions for future commercial cultivation, germplasm conservation, genetic engineering and molecular biology research of this ornamental plant. [ABSTRACT FROM AUTHOR]

Key message: The inhibitory effect of eugenol on rice germination is mediated by a two-step modulatory process: Eugenol first regulates the antagonism of GA and ABA, followed by activation of catalase activity. The natural monoterpene eugenol has been reported to inhibit preharvest sprouting in rice. However, the inhibitory mechanism remains obscure. In this study, simultaneous monitoring of GA and ABA responses by the in vivo GA and ABA-responsive dual-luciferase reporter system showed that eugenol strongly inhibited the GA response after 6 h of imbibition, whereas eugenol significantly enhanced the ABA response after 12 h of imbibition. Gene expression analysis revealed that eugenol significantly induced the ABA biosynthetic genes OsNCED2, OsNCED3, and OsNCED5, but notably suppressed the ABA catabolic genes OsABA8ox1 and OsABA8ox2. Conversely, eugenol inhibited the GA biosynthetic genes OsGA3ox2 and OsGA20ox4 but significantly induced the GA catabolic genes OsGA2ox1 and OsGA2ox3 during imbibition. OsABI4, the key signaling regulator of ABA and GA antagonism, was notably induced before 12 h and suppressed after 24 h by eugenol. Moreover, eugenol markedly reduced the accumulation of H2O2 in seeds after 36 h of imbibition. Further analysis showed that eugenol strongly induced catalase activity, protein accumulation, and the expression of three catalase genes. Most importantly, mitigation of eugenol-inhibited seed germination was found in the catc mutant. These findings indicate that catalase associated with antagonistic changes of ABA and GA is involved in the sequential regulation of eugenol-inhibited seed germination in rice. [ABSTRACT FROM AUTHOR]

The metal‒semiconductor heterojunction is imperative for the realization of electrically driven nanolasers for chip‐level platforms. Progress in developing such nanolasers has hitherto rarely been realized, however, because of their complexity in heterojunction fabrication and the need to use noble metals that are incompatible with microelectronic manufacturing. Most plasmonic nanolasers lase either above a high threshold (101‒103 MW cm−2) or at a cryogenic temperature, and lasing is possible only after they are removed from the substrate to avoid the large ohmic loss and the low modal reflectivity, making monolithic fabrication impossible. Here, for the first time, record‐low‐threshold, room‐temperature ultraviolet (UV) lasing of plasmon‐coupled core‒shell nanowires that are directly grown on silicon is demonstrated. The naturally formed core‒shell metal‒semiconductor heterostructure of the nanowires leads to a 100‐fold improvement in growth density over previous results. This unprecedentedly high nanowire density creates intense plasmonic resonance, which is outcoupled to the resonant Fabry‒Pérot microcavity. By boosting the emission strength by a factor of 100, the hybrid photonic‒plasmonic system successfully facilitates a record‐low laser threshold of 12 kW cm−2 with a spontaneous emission coupling factor as high as ≈0.32 in the 340‒360 nm range. Such architecture is simple and cost‐competitive for future UV sources in silicon integration. [ABSTRACT FROM AUTHOR]

• Annealing-free, Al-doped NiO x nano-particles were synthesized and proposed. • The NiOx was employed as the hole transport layer in Perovskite photovoltaics. • An interfacial dipole of 0.3 eV was found between ITO electrode and the NiO x layer. • Hole extraction efficiency and overall device performances were greatly improved. • No Dimethyl sulfoxide additive was used in devices. Recent researches show that nickel oxide (NiO x) thin films can be utilized as an efficient and stable hole transport layer (HTL) in inverted planar perovskite solar cells (PSCs) replacing costly and chemically unstable organic materials. Nevertheless, thermal annealing process is necessary for NiO x made by conventional methods with metallic dopants, which is not applicable to flexible substrates with low melting points or temperature-sensitive materials. In this work, annealing-free Al-doped NiO x nano-particles (NPs) were synthesized and employed as a HTL in PSCs. Without using any Dimethyl sulfoxide (DMSO) additive in devices, the electrical conductivity, morphology, external quantum efficiency, and power conversion efficiency were all significantly enhanced after 2% Al doping in NiO x. The Ultraviolet Photoemission Spectroscopy (UPS) was conducted to explore the mechanisms behind the device improvements. An interfacial dipole of 0.3 eV was found between the ITO electrode and the NiO x layer directing away from the active layer, boosting the hole extraction efficiency at ITO/MAPbI 3 (MA = methylamine) interface. This work not only provides a deep insight of the ITO/NiO x NPs/perovskite interface but also proposes a new strategy for further development of highly efficient and reliable PSCs. [ABSTRACT FROM AUTHOR]

An electrochemical sensor with high selectivity in addition to sensitivity was developed for the determination of cardiac troponin I (cTnI), based on the modification of cTnI imprinted polymer film on a glassy carbon electrode (GCE). The sensor was fabricated by layer-by-layer assembled graphene nanoplatelets (GS), multiwalled carbon nanotubes (MWCNTs), chitosan (CS), glutaraldehyde (GA) composites, which can increase the electronic transfer rate and the active surface area to capture a larger number of antigenic proteins. MWCNTs/GS based imprinted polymers (MIPs/MWCNTs/GS) were synthesized by means of methacrylic acid (MAA) as the monomer, ethylene glycol dimethacrylate (EGDMA) as the cross linker α,α′-azobisisobutyronitrile (AIBN) as the initiator and cTnI as the template. In comparison with conventional methods, the proposed electrochemical sensor is highly sensitive for cTnI, providing a better linear response range from 0.005 to 60 ng cm −3 and a lower limit of detection (LOD) of 0.0008 ng cm −3 under optimal experimental conditions. In addition, the electrochemical sensor exhibited good specificity, acceptable reproducibility and stability. Moreover, satisfactory results were obtained in real human serum samples, indicating that the developed method has the potential to find application in clinical detection of cTnI as an alternative approach. [ABSTRACT FROM AUTHOR]