Enhanced stability and clinical absorption of a form of encapsulated vitamin A for food fortification.

Food fortification is an effective strategy to address vitamin A (VitA) deficiency, which is the leading cause of childhood blindness and drastically increases mortality from severe infections. However, VitA food fortification remains challenging due to significant degradation during storage and cooking. We utilized an FDA-approved, thermostable, and pH-responsive basic methacrylate copolymer (BMC) to encapsulate and stabilize VitA in microparticles (MPs). Encapsulation of VitA in VitA-BMC MPs greatly improved stability during simulated cooking conditions and long-term storage. VitA absorption was nine times greater from cooked MPs than from cooked free VitA in rats. In a randomized controlled cross-over study in healthy premenopausal women, VitA was readily released from MPs after consumption and had a similar absorption profile to free VitA. This VitA encapsulation technology will enable global food fortification strategies toward eliminating VitA deficiency.

Origins of High Air Sensitivity and Treatment Strategies in O3-Type NaMn1/3 Fe1/3Ni1/3O2.

Sodium-ion layered oxides are one of the most highly regarded sodium-ion cathode materials and are expected to be used in electric vehicles and large-scale grid-level energy storage systems. However, highly air-sensitive issues limit sodium-ion layered oxide cathode materials to maximize cost advantages. Industrial and scientific researchers have been developing cost-effective air sensitivity treatment strategies with little success because the impurity formation mechanism is still unclear. Using density functional theory calculations and ab initio molecular dynamics simulations, this work shows that the poor air stability of O3-type NaMn1/3Fe1/3Ni1/3O2 (NMFNO) may be as follows: (1) low percentage of nonreactive (003) surface; (2) strong surface adsorption capacity and high surface reactivity; and (3) instability of the surface sodium ions. Our physical images point out that the high reactivity of the NMFNO surface originates from the increase in electron loss and unpaired electrons (magnetic moments) of the surface oxygen active site as well as the enhanced metal coactivation effect due to the large radius of the sodium ion. We also found that the hydrolysis reaction requires a higher reactivity of the surface oxygen active site, while the carbon hybridization mode transformation in carbonate formation depends mainly on metal activation and does not even require the involvement of surface oxygen active sites. Based on the calculation results and our proposed physical images, we discuss the feasibility of these treatment strategies (including surface morphology modulation, cation/anion substitution, and surface configuration design) for air-sensitive issues.

Spinal histamine H4 receptor mediates chronic pruritus via p-ERK in acetone-ether-water (AEW)-induced dry skin mice.

Dry skin is common to many pruritic diseases and is difficult to improve with oral traditional antihistamines. Recently, increasing evidence indicated that histamine H4 receptor (H4R) plays an important role in the occurrence and development of pruritus. Extracellular signal-regulated kinase (ERK) phosphorylation activation in the spinal cord mediates histamine-induced acute and choric itch. However, whether the histamine H4 receptor regulates ERK activation in the dry skin itch remains unclear. In the study, we explore the role of the histamine H4 receptor and p-ERK in the spinal cord in a dry skin mouse model induced by acetone-ether-water (AEW). q-PCR, Western blot, pharmacology and immunofluorescence  were applied in the study. We established a dry skin itch model by repeated application of AEW on the nape of neck in mice. The AEW mice showed typically dry skin histological change and persistent spontaneous scratching behaviour. Histamine H4 receptor, instead of histamine H1 receptor, mediated spontaneous scratching behaviour in AEW mice. Moreover, c-Fos and p-ERK expression in the spinal cord neurons were increased and co-labelled with GRPR-positive neurons in AEW mice. Furthermore, H4R agonist 4-methyhistamine dihydrochloride (4-MH)induced itch. Both 4-MH-induced itch and the spontaneous itch in AEW mice were blocked by p-ERK inhibitor U0126. Finally, intrathecal H4R receptor antagonist JNJ7777120 inhibited spinal p-ERK expression in AEW mice. Our results indicated that spinal H4R mediates itch via ERK activation in the AEW-induced dry skin mice.

Color image guided depth image reconstruction based on a total variation network.

A representative method to improve a depth image is to use an aligned high-quality color image to guide the depth image by migrating the color details to the depth image. In the process of color-guided depth reconstruction, there often is a misalignment of the edge of the color image used to guide the depth image reconstruction and the depth discontinuity of the depth image. This makes the results suffer from texture copy artifacts and blurring depth discontinuities. In this paper, we use a total variation deep network founded on deep learning and high-resolution color images. The experimental result indicates that under the guidance of high-resolution colors, the depth image recovered is closest to the ground truth in the edge contour, the PSNR and FSIM index are suboptimal for 64×, and the contour and position information recovered from the reconstructed depth image can be retained in the very low-resolution depth image.

Correlation of Blood and Intestinal Mucosa miR-34a Expressions with Disease Severity in Ulcerative Colitis Patients.

BACKGROUND: miR-34a has been implicated in many autoimmune diseases and gastrointestinal diseases. However, the expression of miR-34 in ulcerative colitis (UC) patients were not fully studied. This study was performed to in-vestigate the association of blood and intestinal tissue miR-34a expression of patients with disease severity in UC patients. METHODS: Our study enrolled 82 patients with UC and 80 age- and gender- matched healthy individuals. Blood miR-34a expressions were detected using reverse transcription-polymerase chain reaction (RT-PCR). Local intestinal miR-34a, STAT3 mRNA and IL-23 mRNA expressions were also detected in the lesioned area and adjacent non-affected intestinal tissue in patients. Disease severity of UC was assessed by Mayo score. The diagnostic value of both blood and local miR-34a expression for UC patients was assessed by receiver operating characteristic (ROC) curve. RESULTS: Blood miR-34a was increased in UC patients in contrast with healthy individuals with statistical significance. In UC patients, local intestinal miR-34a expressions were markedly upregulated compared to adjacent non-affected intestinal tissue. Local intestinal miR-34a expressions were positively correlated with STAT3 mRNA and IL-23 mNRA. Both blood and local miR-34a expressions were significantly and positively related to Mayo scores. ROC curve analysis indicated that both blood and local miR-34a expressions may act as decent marker for Mayo grade. CONCLUSIONS: Blood and intestinal tissue miR-34a expressions are correlated with disease severity in UC patients. Both blood and intestinal tissue miR-34a expressions may serve as potential diagnostic and prognostic makers for UC. Therapeutic methods targeting miR-34a may act as potential ways for UC treatment.

Cylinder power progression associated with axial length in young children: a two-year follow-up study.

PURPOSE: To describe the association of refraction development and axial length (AL) in young children and provide new insights into the progression of cylinder power. METHODS: Children (2-3 grades) were enrolled from primary schools in Shanghai and followed up for two years. Cycloplegic refraction, AL, and corneal curvature radius were measured. Refraction parameters were compared among groups with different AL, AL1 (AL < 23.5 mm), AL2 (23.5 mm ≤ AL < 24.5 mm), and AL3 (AL ≥ 24.5 mm). Multiple regression analysis was used to explore risk factors of diopter of cylinder (DC) progression. RESULTS: In total, out of 6891 enrolled children, 5961 participants (7-11 yrs) were included in the final analysis. Over the two-year period, the cylinder power significantly changed, and those with longer AL had more rapid DC progression over the two years (AL1, -0.09 ± 0.35 D; AL2, -0.15 ± 0.39 D; AL3, -0.29 ± 0.44 D) (P < 0.001). The change in DC was independently associated with AL at baseline (P < 0.001). The proportion of with-the-rule astigmatism increased from 91.3% to 92.1% in AL1 group, from 89.1% to 91.8% in AL2 group and from 87.1% to 92.0% in AL3 group. CONCLUSIONS: Young children with long AL experienced rapid progression of cylinder power. Both the control of myopia progression and attention to the correction of astigmatism are necessary in the health management of children with long AL. The significantly increased AL in participants might contribute to both the extent and direction of astigmatism.

Association between ambient air pollution and age-related macular degeneration: a meta-analysis.

BACKGROUND: Several epidemiological studies have investigated the association between ambient air pollution and age-related macular degeneration (AMD). However, a consensus has not yet been reached. Our meta-analysis aimed to clarify this association. METHODS: Databases, including PubMed, EMBASE, and Web of Science, were searched for relevant studies from 01 January 2000 to 30 January 2024. English-language, peer-reviewed studies using cross-sectional, prospective, or retrospective cohorts and case-control studies exploring this relationship were included. Two authors independently extracted data and assessed study quality. A random-effects model was used to calculate pooled covariate-adjusted odds ratios. Heterogeneity across studies was also tested. RESULTS: We identified 358 relevant studies, of which eight were included in the meta-analysis. Four studies evaluated the association between particulate matter less than 2.5 µm in diameter (PM2.5) and AMD, and three studies explored the relationship between nitrogen dioxide (NO2) or ozone (O3) and AMD. The pooled odds ratios were 1.16 (95% confidence interval [CI]: 1.11-1.21), 1.17 (95% CI: 1.09-1.25), and 1.06 (95% CI: 1.05-1.07), respectively. CONCLUSION: Current evidence suggests a concomitant positive but not causal relationship between PM2.5, NO2, or O3 and AMD risk.

Establishing and applying an adaptive framework for imported malaria: a field practice in Anhui Province, China from 2012 to 2022.

BACKGROUND: Anhui Province is currently facing an increase in imported malaria cases as a result of globalization and international travel. In response, Anhui Province has implemented a comprehensive adaptive framework to effectively address this threat. METHODS: This study collected surveillance data from 2012 to 2022 in Anhui Province. Descriptive statistics were used to analyze the epidemiological characteristics of imported malaria cases. Additionally, multivariate logistic regression was employed to identify factors associated with severe malaria. Documents were reviewed to document the evolution of the adaptive framework designed to combat imported malaria. The effectiveness of the adaptive framework was evaluated based on the rates of timely medical visits, timely diagnosis, and species identification. RESULTS: During the study period, a total of 1008 imported malaria cases were reported across 77 out of 105 counties in Anhui Province, representing a coverage of 73.33%. It was found that 10.52% of imported cases went undiagnosed for more than seven days after onset. The multivariate analysis revealed several potential risk factors for severe malaria, including increasing age (OR = 1.049, 95%CI:1.015-1.083), occupation (waitperson vs. worker, OR = 2.698, 95%CI:1.054-6.906), a longer time interval between onset and the initial medical visit (OR = 1.061, 95%CI:1.011-1.114), and misdiagnosis during the first medical visit (OR = 5.167, 95%CI:2.535-10.533). Following the implementation of the adaptive framework, the rates of timely medical visits, timely diagnosis, and species identification reached 100.00%, 78.57%, and 100.00%, respectively. CONCLUSIONS: Anhui Province has successfully developed and implemented an adaptive framework for addressing imported malaria, focusing on robust surveillance, prompt diagnosis, and standardized treatment. The experiences gained from this initiative can serve as a valuable reference for other non-endemic areas.

Trp-574-Leu mutation and metabolic resistance by cytochrome P450 gene conferred high resistance to ALS-inhibiting herbicides in Descurainia sophia.

Descurainia sophia (flixweed) is a troublesome weed in winter wheat fields in North China. Resistant D. sophia populations with different acetolactate synthetase (ALS) mutations have been reported in recent years. In addition, metabolic resistance to ALS-inhibiting herbicides has also been identified. In this study, we collected and purified two resistant D. sophia populations (R1 and R2), which were collected from winter wheat fields where tribenuron-methyl provided no control of D. sophia at 30 g a.i. ha-1. Whole plant bioassay and ALS activity assay results showed the R1 and R2 populations had evolved high-level resistance to tribenuron-methyl and florasulam and cross-resistance to imazethapyr and pyrithiobac­sodium. The two ALS genes were cloned from the leaves of R1 and R2 populations, ALS1 (2004 bp) and ALS2 (1998 bp). A mutation of Trp 574 to Leu in ALS1 was present in both R1 and R2. ALS1 and ALS2 were cloned from R1 and R2 populations respectively and transferred into Arabidopsis thaliana. Homozygous T3 transgenic seedlings with ALS1 of R1 or R2 were resistant to ALS-inhibiting herbicides and the resistant levels were the same. Transgenic seedlings with ALS2 from R1 or R2 were susceptible to ALS-inhibiting herbicides. Treatment with cytochrome P450 inhibitor malathion decreased the resistant levels to tribenuron-methyl in R1 and R2. RNA-Seq was used to identify target cytochrome P450 genes possibly involved in resistance to ALS-inhibiting herbicides. There were five up-regulated differentially expressed cytochrome P450 genes: CYP72A15, CYP83B1, CYP81D8, CYP72A13 and CYP71A12. Among of them, CYP72A15 had the highest expression level in R1 and R2 populations. The R1 and R2 populations of D. sophia have evolved resistance to ALS-inhibiting herbicides due to Trp 574 Leu mutation in ALS1 and possibly other mechanisms. The resistant function of CYP72A15 needs further research.

Diverse ALS mutations and cross-and multiple-resistance to ALS and EPSPS inhibitors in flucarbazone­sodium-resistant Bromus japonicus populations from Hebei province, China.

Japanese brome (Bromus japonicus) has become one of the main weeds in wheat fields in Hebei province of China and causes a large decrease of wheat production. A total of 44 putative resistant and 2 susceptible Japanese brome populations were collected in the 2021/2022 crop season from Hebei province of China to determine resistance levels to flucarbazone­sodium and to investigate the diversity of acetolactate synthase (ALS) mutations, as well as to confirm the cross-and multiple-resistance levels to ALS and EPSPS (5-enolpyruvate shikimate-3-phosphate synthetase) inhibitors. Whole plant bioassay results showed that 15 out of 44 populations tested or 34% were resistant to flucarbazone­sodium. The resistance indices of Japanese brome to flucarbazone­sodium ranged from 43 to 1977. The resistant populations were mainly distributed in Baoding and Shijiazhuang districts, and there was only one resistant population in Langfang district. Resistant Japanese brome had diverse ALS mutations, including Pro-197-Ser, -Thr, -Arg and Asp-376-Glu. The incidence of Pro-197-Ser mutation was the highest at 68%. Application of the CYP450 inhibitor malathion suggested that CYP450 was involved in metabolic resistance in a population without an ALS mutation. The population with Pro-197-Thr mutation evolved weak cross-resistance to mesosulfuron-methyl and pyroxsulam, and it is in the process of evolving multiple-resistance to glyphosate.

Medical image segmentation of gastric adenocarcinoma based on dense connection of residuals.

BACKGROUND AND OBJECTIVE: Accurate segmentation of gastric cancer based on CT images of gastric adenocarcinoma is crucial for physicians to screen gastric diseases, clinical diagnosis, preoperative prediction, and postoperative evaluation plans. To address the issue of the inability of the segmentation algorithm to depict the correct boundaries due to unclear gastric contours in the lesion area and the visible irregular band-like dense shadow extending to the perigastric region, a 3D medical image segmentation model 3D UNet based on residual dense jumping method is proposed. METHODS: In the method we proposed, Residual Dense Block, which is applied to the image super-resolution module to remove CT artifacts, and Residual Block in ResNet are further fused. The quality of CT images is improved by Residual Dense Skip Block, which removes banded dense shadows, preserves image details and edge information, captures features, and improves the segmentation performance of gastric adenocarcinoma. The Instance Normalization layer position is modified to select the best result. Different loss functions are also combined in order to obtain the best gastric adenocarcinoma segmentation performance. RESULTS: We tested the model on a hospital-provided gastric adenocarcinoma dataset. The experimental results show that our model outperforms the existing methods in CT gastric adenocarcinoma segmentation, in which the method combining the hybrid loss function of Dice and CE obtains an average dice score of 82.3%, which is improved by 5.3% and 3.8% compared to TransUNet and Hiformer, respectively, and improves the cross-merge rate to 70.8%, compared to nnFormer, nnUNet by 1% and 0.9%, respectively. CONCLUSIONS: The residual jump connection structure indeed improves segmentation performance. The proposed method has the potential to be used as a screen for gastric diseases and to assist physicians in diagnosis.

Microfluidized hemp protein isolate: an effective stabilizer for high-internal-phase emulsions with improved oxidative stability.

BACKGROUND: Hemp protein isolates (HPIs), which provide a well-balanced profile of essential amino acids comparable to other high-quality proteins, have recently garnered significant attention. However, the underutilized functional attributes of HPIs have constrained their potential commercial applications within the food and agriculture field. This study advocates the utilization of dynamic-high-pressure-microfluidization (DHPM) for the production of stable high-internal-phase emulsions (HIPEs), offering an efficient approach to fully exploit the potential of HPI resources. RESULTS: The findings underscore the effectiveness of DHPM in producing HPI as a stabilizing agent for HIPEs with augmented antioxidant activity. Microfluidized HPI exhibited consistent adsorption and anchoring at the oil-water interface, resulting in the formation of a dense and compact layer. Concurrently, the compression of droplets within HIPEs gave rise to a polyhedral framework, conferring viscoelastic properties and a quasi-solid behavior to the emulsion. Remarkably, HIPEs stabilized by microfluidized HPI demonstrated superior oxidative and storage stability, attributable to the establishment of an antioxidative barrier by microfluidized HPI particles. CONCLUSION: This study presents an appealing approach for transforming liquid oils into solid-like fats using HPI particles, all without the need for surfactants. HIPEs stabilized by microfluidized HPI particles hold promise as emerging food ingredients for the development of emulsion-based formulations with enhanced oxidative stability, thereby finding application in the food and agricultural industries. © 2023 Society of Chemical Industry.

Protective Effect of Dihydromyricetin Against Exercise-Induced Muscle Damage and Its Mechanism.

Objective To investigate the protective effect of dihydromyricetin (DHM) against exercise-induced muscle damage (EIMD) in mice and its potential mechanism.Methods Adult male C57BL/6J mice were randomly divided into control group (CG), exercise group (EG), and exercise + 100 mg/kg weight ·d DHM (DHM) group. The intervention lasted for four weeks, during which the animals in the EG and DHM groups were subjected to exercise training for 1 h per day. The day after the training, a 90-min treadmill exercise (slope: 0 and speed: 18 m/min) was conducted in both EG and DHM groups. Samples of blood and gastrocnemius muscles were harvested from the three groups 24 h after the exercise, followed by the measurement of serum creatine kinase (CK) and lactate dehydrogenase (LDH) activities, total superoxide dismutase (T-SOD) activity, malondialdehyde (MDA), and skeletal muscle mitochondrial enzyme complex I and II activities. Histological changes in the skeletal muscle were observed by transmission electron microscopy, and the protein expressions of mitochondrial function-related pathways were detected by Western blotting.Results Skeletal muscle morphological changes and mitochondrial damage were alleviated in the DHM group compared to those in the EG. The activities of EIMD markers CK and LDH and the level of lipid peroxidation were notably repressed and the serum T-SOD activity was enhanced after DHM intervention. Western blotting demonstrated that the expressions of sirtuin type 3 (SIRT3), estrogen-related receptor alpha, and peroxisome proliferator-activated receptor-gamma coactivator-1 alpha in the skeletal muscle of mice increased after the DHM intervention.Conclusion DHM can relieve EIMD in mice, possibly by promoting the recovery of the mitochondrial structure and function in the skeletal muscle of mice after high-intensity exercise via the activation of the SIRT3 signaling pathway.

The Effects of a Nonpharmacological Intervention Practice for Older Adults with Mild Cognitive Impairment and Their Family Caregivers in China.

Mild cognitive impairment (MCI) marks a critical phase in the progression to dementia. In our study, social workers utilized the Multicomponent Nonpharmacological Intervention Approach (MCNIA) to aid MCI participants (N = 52) and their caregivers, dividing into intervention and control groups. The intervention group underwent an additional regimen of non-pharmacological therapies besides pharmacological treatment. Our findings highlighted that: 1) MCNIA significantly enhanced cognitive and daily living abilities in the intervention group; 2) Caregivers experienced reduced burdens and improved social support; 3) Correlation analyses involving biomarkers indicated that MCNIA was particularly effective in alleviating depression in those with slightly more severe cognitive impairment.

Research progress on the application of cell-free synthesis systems for enzymatic processes.

Cell-free synthesis systems can complete the transcription and translation process in vitro to produce complex proteins that are difficult to be expressed in traditional cell-based systems. Such systems also can be used for the assembly of efficient localized multienzyme cascades to synthesize products that are toxic to cells. Cell-free synthesis systems provide a simpler and faster engineering solution than living cells, allowing unprecedented design freedom. This paper reviews the latest progress on the application of cell-free synthesis systems in the field of enzymatic catalysis, including cell-free protein synthesis and cell-free metabolic engineering. In cell-free protein synthesis: complex proteins, toxic proteins, membrane proteins, and artificial proteins containing non-natural amino acids can be easily synthesized by directly controlling the reaction conditions in the cell-free system. In cell-free metabolic engineering, the synthesis of desired products can be made more specific and efficient by designing metabolic pathways and screening biocatalysts based on purified enzymes or crude extracts. Through the combination of cell-free synthesis systems and emerging technologies, such as: synthetic biology, microfluidic control, cofactor regeneration, and artificial scaffolds, we will be able to build increasingly complex biomolecule systems. In the next few years, these technologies are expected to mature and reach industrialization, providing innovative platforms for a wide range of biotechnological applications.

Interfacial Behaviors of Giant Amphiphilic Molecules Composed of Hydrophobic Isobutyl POSS and Hydrophilic POSS Bearing Carboxylic Acid Groups at the Air-Water Interface.

The behavior of giant amphiphilic molecules at the air-water interface has become a subject of concern to researchers. Small changes in the molecular structure can cause obvious differences in the molecular arrangement and interfacial properties of the monolayer. In this study, we have systematically investigated the interfacial behaviors of the giant amphiphilic molecules with different number of hydrophobic BPOSS blocks and one hydrophilic ACPOSS block ((BPOSS)n-ACPOSS (n = 1-5)) at the air-water interface by the surface pressure-area (π-A) isotherm, Brewster angle microscopy (BAM), compression modulus measurement, and hysteresis measurement. We found that both the number of BPOSS blocks and the compression rate can significantly influence the interfacial behaviors of giant molecules. The π-A isotherms of giant molecules (BPOSS)n-ACPOSS (n = 2-5) exhibit a "cusp" phenomenon which can be attributed to the transition from monolayer to multilayer. However, the cusp is dramatically different from the "collapse" of the monolayer studied in other molecular systems, which is highly dependent on the compression rate of the monolayer. In addition, the compression modulus and hysteresis measurements reveal that the number of BPOSS blocks of (BPOSS)n-ACPOSS plays an important role in the static elasticity, stability, and reversibility of the Langmuir films.

Organocalcium Hydride-Catalyzed Intramolecular C(sp3)-H Annulation of Functionalized 2,6-Lutidines.

This work reports an intramolecular C(sp3)-H annulation of functionalized 2,6-lutidines catalyzed by an organocalcium hydride [{(DIPPnacnac)CaH(thf)}2] (DIPPnacnac = CH{(CMe)(2,6-iPr2-C6H3N)}2). This reaction constitutes a streamlined approach for producing a new family of tetrahydro-1,5-naphthyridines and hexahydropyrido[3,2-b]azocines derivatives in good to excellent yields with high atom efficiency and broad substrates scope. A calcium alkyl complex was isolated from the stoichiometric reaction between calcium hydride and the substrate through deprotonation, which was structurally characterized and confirmed as the catalytic intermediate.

Double Bond Cleavage in Small Molecules Using a Geminal Sc/P Lewis Pair.

Frustrated Lewis pairs (FLPs) have proven capable of cleaving the H-H σ-bond and binding a variety of unsaturated small molecules. In contrast, examples of FLP-mediated complete rupture of double-bonded substrates remain scarce. Herein, we present a geminal Sc/P Lewis pair, i.e., (ArO)2ScN(tBu)PPh2 (Ar = 2,6-tBu2-C6H3), that exhibits typical FLP-type 1,2-addition reactivity toward CO2. Notably, it enables the complete cleavage of a series of double bonds, such as the N═N bond in azobenzene or pyridazine, the N═O bond in nitrosobenzene, and the N═S and S═O bonds in N-sulfinylaniline, to yield the corresponding metallacyclic products. Moreover, the first rare-earth metal sulfur monoxide adduct could be obtained through the bond cleavage of PhNSO, demonstrating the capability of rare-earth metal complexes to capture reactive species.

Study on extraction and characterization of new antibiotics violacein from engineered Escherichia coli VioABCDE-SD.

To better understand the characteristic properties of violacein biosynthesized by engineered Escherichia coli VioABCDE-SD, a convenient and simplified method was designed to extract violacein and its stability, antimicrobial activity, and antioxidant capacity were analyzed. Different from the traditional extraction methods, our new method is easier and less time consuming and can directly obtain violacein dry powder product with a higher extraction rate. Low temperature, dark condition, neutral pH, reducing agents, Ba2+ , Mn2+ , Ni2+ , Co2+ , and some food additives of sucrose, xylose, and glucose were conducive to maintaining its stability. The violacein also exhibited surprisingly high bacteriostatic action against Gram-positive Bacillus subtilis, Deinococcus radiodurans R1, and Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa, but no effect on E. coli. The violacein of VioABCDE-SD exhibited strong antioxidant activity, with the scavenging rate of 1,1-diphenyl-2-picrylhydrazyl free radicals reaching 60.33%, the scavenging efficiency of hydroxyl radical scavenging reaching 56.34%, and the total antioxidant capacity reaching 0.63 U/mL. Violacein from VioABCDE-SD can be synthesized directionally with better stability, antibacterial, and antioxidant properties compared with that from the original strain Janthinobacterium sp. B9-8. Therefore, our study indicated that violacein from engineered E. coli VioABCDE-SD was a kind of new antibiotic with potential biological activities, which may have potential utility in multiple areas such as pharmacological, cosmetics, and healthy food industries.

Discrete Hartley transform-based dual-mode index modulation OFDM for visible light communications.

Using discrete Hartley transform (DHT) instead of discrete Fourier transform (DFT) in the optical index modulation (IM) aided orthogonal frequency division multiplexing (OFDM) systems for visible light communications (VLC) results in improvement in terms of the spectral efficiency, energy efficiency, peak-to-average power ratio, and bit error rate (BER) performance with a lower computational complexity, benefiting from the removal of the Hermitian symmetry. In this paper, by employing dual-mode (DM) index modulation in the DHT-based OFDM systems, more spectral efficient schemes for VLC are proposed. A reduced-complexity maximum likelihood (ML) detector and a simple log-likelihood ratio (LLR) detector for the DM-OFDM-IM systems are presented, achieving a better performance with a lower complexity over the traditional detectors. The spectral efficiency and the average BER are analyzed. The minimum distance between different transmitted subblock vectors is calculated for characterizing the performance. The simulation results demonstrate that the DHT-based DM-OFDM-IM systems achieve significant performance gains over the DHT-based OFDM-IM counterparts and perform better than the DFT-based counterparts in terms of the spectral efficiency and BER performance.