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Abstract In treating infectious diseases, achieving selective bacterial inhibition is crucial for preserving the microecological equilibrium. The current approaches predominantly rely on synthetic materials tailored to specific bacteria, considering their cell walls or oxygen requirements. Herein, inspired by intricate bacterial communication, a natural implant is proposed coating utilizing bacterial outer membrane vesicles (OMVs), essential components in bacterial signaling, integrated onto diverse implant surfaces through a universal poly (tannic acid) bridging layer. This coating is homogenous and stable, unexpectedly promoting the proliferation of parental bacteria while inhibiting heterologous bacteria both in vitro and in vivo. Through high‐throughput sequencing and bioinformatics analysis, the selective bacteriostatic ability arises from OMVs, upregulating anti‐oxidative stress genes in heterologous bacteria and activating biofilm‐related genes in parental bacteria. This study positions OMVs as an appealing biomaterial for selective bacterial inhibition through a biological approach, showcasing their potential in regulating the microecological balance through a natural interface modification strategy.

Infection and poor osteogenesis are two major causes of implant failure. Surface modification strategy provides solutions to the above problems. However, the functional requirements at different biological stages during infectious bone repair and the oxidative stimulation caused by reactive oxygen species (ROS) in an inflammatory environment pose challenges to the existing approaches. Layer-by-layer (LbL) self-assembly realizes layer by layer superposition and time-dependent acting of different bioactive components, but is demanding to functional groups. Tannic acid (TA) owns abundant phenolic hydroxyl groups, endowing various firm chemical bindings and excellent antioxidant property. To this end, we developed a time-dependent and antioxidant multifunctional coating via TA mediated LbL self-assembly. This layer exhibited higher ROS removal capacity and stronger binding ability. Furthermore, it showed rapid and excellent antibacterial ability of over 85 % against Staphylococcus aureus and Escherichia coli at 24 h, which additionally promoted osteogenic differentiation in vitro in long term. Moreover, the coating exhibited outstanding antibacterial and bone regeneration performance in vivo as well. Thus, this study is expected to provide an antioxidant and time-dependent multifunctional platform for surface modification engineering of dental and orthopedic implantation, as well as other potential biological material designs.

Numerous surface modification strategies for ordinary titanium (Ti) implant have been proposed since Ti lacks antibacterial and osteogenic characteristics. However, the majority of surface modifying materials currently do not consider the microenvironmental demands that are constantly changing ——Antibacterial is required at the early stage after implantation and osteogenesis becomes an intense appeal at the later stage. In the present study, strontium ranelate (SrR) and chitosan (CTS) were loaded onto the titanium surface via layer-by-layer (LbL) self-assembly based on tannic acid (TA) with separate antimicrobial and osteogenic layers. The obtained Titanium-Strontium Ranelate-Chitosan (Ti-SrR-CTS) implant achieved an outstanding early-stage antibacterial effect against S. aureus and E. coli and a more prominent late-stage osteogenic effect than ordinary titanium implant in vitro. In vivo results further verified that Ti-SrR-CTS implants had 97.68% antibacterial efficacy and 1.82 times the amount of new bone compared to ordinary titanium at different stages, respectively. This work has successfully designed a novel implant coating with both excellent antimicrobial and osteogenic properties, which provides a promising surface modification strategy for orthopedic applications.

ABSTRACT: The processing and analysis of massive high-dimensional datasets are important issues in precision livestock farming (PLF). This study explored the use of multivariate analysis tools to analyze environmental data from multiple sensors located throughout a broiler house. An experiment was conducted to collect a comprehensive set of environmental data including particulate matter (TSP, PM10, and PM2.5), ammonia, carbon dioxide, air temperature, relative humidity, and in-cage and aisle wind speeds from 60 locations in a typical commercial broiler house. The dataset was divided into 3 growth phases (wk 1–3, 4–6, and 7–9). Spearman's correlation analysis and principal component analysis (PCA) were used to investigate the latent associations between environmental variables resulting in the identification of variables that played important roles in indoor air quality. Three cluster analysis methods; k-means, k-medoids, and fuzzy c-means cluster analysis (FCM), were used to group the measured parameters based on their environmental impact in the broiler house. In general, the Spearman and PCA results showed that the in-cage wind speed, aisle wind speed, and relative humidity played critical roles in indoor air quality distribution during broiler rearing. All 3 clustering methods were found to be suitable for grouping data, with FCM outperforming the other 2. Using data clustering, the broiler house spaces were divided into 3, 2, and 2 subspaces (clusters) for wk 1 to 3, 4 to 6, and 7 to 9, respectively. The subspace in the center of the house had a poorer air quality than other subspaces.

High catalytic performances of metal-semiconductor heterostructures have gained significant attention in recent years. However, developing fast and low-cost synthesis of multiphase heterojunction catalysts has long been a challenge. Herein, three phases of Cu-CeO2-SrTiO3-δ heterojunction catalyst are successfully synthesized by combining with sol-gel and rapid plasma exsolution method. Using dielectric barrier discharge plasma (DBD), Cu nanoparticles are exsolved and uniformly distributed on the surface of CeO2-SrTiO3-δ. This unique multiphase heterojunction catalyst exhibits superior performance in photothermal reverse water gas shift (RWGS) reactions. The yield of CO from this catalyst is impressive at 11.32 mmol g−1 h−1, 9 times greater than pure SrTiO3, and the selectivity for CO is high (99.95%). The enhanced activity is primarily attributed to the synergistic effect resulting from the incorporation of three phases of Cu nanoparticles, CeO2, and SrTiO3-δ, as well as their interfaces. The increase in oxygen vacancy sites in CeO2 enhances the adsorption of CO2, whereas the doping and exsolution of Cu help to broaden the light absorption range. A significant role is played by the localized surface plasmon resonance (LSPR) effect of Cu nanoparticles in promoting the catalytic performance of RWGS. This study demonstrates a simple and efficient method for fabricating multiphase heterojunction catalysts, providing new strategies for photothermal CO2 reduction.

Singlet fission (SF) is a spin-conserving process converting 1 singlet exciton into 2 triplet excitons. This exciton multiplication mechanism offers an attractive route to solar cells that circumvent the single-junction Shockley–Queisser limit. However, it remains unclear how intermolecular coupling, which is subject to the aggregation extent in thin-film morphology, controls SF pathways and dynamics. The prototype molecule 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene) has been extensively studied to investigate SF mechanisms. However, previous literature reports have presented divergent SF mechanisms and pathways in TIPS-pentacene films. In this study, solvent vapor annealing treatment is used to deliberately adjust the aggregation extent in TIPS-pentacene films. This enables us to reproduce various SF pathways reported in the literature under the same experimental conditions, with the only variation being the level of aggregation. These results shed light on the crucial role that molecular aggregation plays in modulating both the SF mechanism and pathway and reconciles the previously contentious SF mechanisms and pathways reported in TIPS-pentacene films. Our study offers substantial insights into the understanding of the SF mechanism and provides a potential avenue for future control of SF pathways in accordance with specific application requirements.

Abstract Background The function of the insula has been increasingly mentioned in neurocircuitry models of obsessive-compulsive disorder (OCD) for its role in affective processing and regulating anxiety and its wide interactions with the classic cortico-striato-thalamo-cortical circuit. However, the insular resting-state functional connectivity patterns in OCD remain unclear. Therefore, we aimed to investigate characteristic intrinsic connectivity alterations of the insula in OCD and their associations with clinical features. Methods We obtained resting-state functional magnetic resonance imaging data from 85 drug-free OCD patients and 85 age- and sex-matched healthy controls (HCs). We performed a general linear model to compare the whole-brain intrinsic functional connectivity maps of the bilateral insula between the OCD and HC groups. In addition, we further explored the relationship between the intrinsic functional connectivity alterations of the insula and clinical features using Pearson or Spearman correlation analysis. Results Compared with HCs, patients with OCD exhibited increased intrinsic connectivity between the bilateral insula and bilateral precuneus gyrus extending to the inferior parietal lobule and supplementary motor area. Decreased intrinsic connectivity was only found between the right insula and bilateral lingual gyrus in OCD patients relative to HC subjects, which was negatively correlated with the severity of depression symptoms in the OCD group. Conclusion In the current study, we identified impaired insular intrinsic connectivity in OCD patients and the dysconnectivity of the right insula and bilateral lingual gyrus associated with the depressive severity of OCD patients. These findings provide neuroimaging evidence for the involvement of the insula in OCD and suggest its potential role in the depressive symptoms of OCD.

BackgroundInsomnia is a commonly seen symptom in adolescents with major depressive disorder (MDD). The suprachiasmatic nucleus (SCN), which is the circadian rhythm regulation center, plays a crucial role in the regulation of sleep-wake circulation. Nevertheless, how SCN function contributes to the exact neural mechanisms underlying the associations between insomnia and depressive symptoms has not been explored in adolescents. In the current study, we aimed to explore the relationship between SCN functional connectivity (FC) and insomnia symptoms in adolescents with MDD using a seed-based FC method.MethodsIn the current study, we recruited sixty-eight first-episode drug-naïve adolescents with MDD and classified them into high insomnia (MDD-HI) and low insomnia (MDD-LI) groups according to the sleep disturbance subscale of the Hamilton Depression Rating Scale (HAMD-S). Forty-three age/gender-matched healthy controls (HCs) were also recruited. SCN FC maps were generally for all subjects and compared among three groups using one-way ANOVA with age, gender and adjusted HAMD score as covariates. We used partial correlations to explore associations between altered FC and clinical symptoms, including sleep quality scores.ResultsAdolescents with MDD showed worse sleep quality, which positively correlated with the severity of depression. Compared to MDD-LI and HCs, MDD-HI adolescents demonstrated significantly decreased FC between the right SCN and bilateral precuneus, and there was no significant difference between the MDD-LI and HC groups. The HAMD-S scores were negatively correlated with bilateral SCN-precuneus connectivity, and the retardation factor score of HAMD was negatively correlated with right SCN-precuneus connectivity.ConclusionThe altered FC between the SCN and precuneus may underline the neural mechanism of sleep-related symptoms in depressive adolescents and provide potential targets for personalized treatment strategies.

BackgroundAlthough the specific role of the uncinate fasciculus (UF) in emotional processing in patients with obsessive–compulsive disorder (OCD) has been investigated, the exact focal abnormalities in the UF have not been identified. The aim of the current study was to identify focal abnormalities in the white matter (WM) microstructure of the UF and to determine the associations between clinical features and structural neural substrates.MethodsIn total, 71 drug-naïve patients with OCD and 81 age- and sex-matched healthy controls (HCs) were included. Automated fiber quantification (AFQ), a tract-based quantitative approach, was adopted to measure alterations in diffusion parameters, including fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD), along the trajectory of the UF. Additionally, we utilized partial correlation analyses to explore the relationship between the altered diffusion parameters and clinical characteristics.ResultsOCD patients showed significantly higher FA and lower RD at the level of the temporal and insular portions in the left UF than HCs. In the insular segments of the left UF, increased FA was positively correlated with the Hamilton Anxiety Scale (HAMA) score, while decreased RD was negatively correlated with the duration of illness.ConclusionWe observed specific focal abnormalities in the left UF in adult patients with OCD. Correlations with measures of anxiety and duration of illness underscore the functional importance of the insular portion of left UF disturbance in OCD patients.

Diosgenin serves as an important precursor of most steroidal drugs in market. Cholesterol was previously deemed as a sterol origin leading to diosgenin biosynthesis. This study reports that cholesterol is not in parallel with diosgenin biosynthesis in Trigonella foenum-graecum. We first perturbed its sterol composition using inhibitors specific for the upstream isoprenoid pathway enzymes, HMGR (3-hydroxy-3-methylgutaryl-CoA reductase) on the mevalonate (MVA) and DXR (1-deoxy-D-xylulose-5-phosphate reductoisomerase) on the 2-C-methyl-D-erythritol-4-phophate (MEP) pathways, and have revealed that diosgenin and cholesterol reversely or differently accumulated in either the MVA or the MEP pathway-suppressed plants, challenging the previously proposed role of cholesterol in diosgenin biosynthesis. To further investigate this, we altered the sterol composition by suppressing and overexpressing the 24-sterol methyltransferase type 1 (SMT1) gene in T. foenum-graecum, as SMT1 acts in the first committed step of diverting the carbon flux of cholesterol toward biosynthesis of 24-alkyl sterols. Knockdown of TfSMT1 expression led to increased cholesterol level but caused a large reduction of diosgenin. Diosgenin was increased upon the TfSMT1-overexpressing, which, however, did not significantly affect cholesterol biosynthesis. These data consistently supported that diosgenin biosynthesis in T. foenum-graecum is not associated with cholesterol. Rather, campesterol, a 24-alkyl sterol, was indicative of being correlative to diosgenin biosynthesis in T. foenum-graecum.

Paris polyphylla var. chinensis (Franch.) Hara is a perennial herb belonging to the Trilliaceae family. Ultraperformance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC/Q–TOF MS) was used to detect the composition of different fractions of Paris polyphylla var. chinensis leaves. Meanwhile, the extracts of different fractions were evaluated for their cytotoxic activities against four selected human cancer cell lines and one human normal epithelial cell line based on the MTT assay method. Multivariate statistical analysis was performed to screen differential compounds and to analyze the distributions between different fractions. Finally, more than 60 compounds were obtained and identified from the different fractions of Paris polyphylla var. chinensis leaves, and the chloroform and n−butanol extracts showed significant cytotoxic effects on these four cancer cells. Several compounds were preliminarily identified from different fractions, including 36 steroidal saponins, 11 flavonoids, 10 ceramides, 8 lipids, 6 organic acids, and 8 other compounds. Various compounds were screened out as different chemical components of different fractions, which were considered as a potential substance basis for the cytotoxicity of Paris polyphylla var. chinensis leaves.

(Iso)flavonoids are one of the largest groups of natural phenolic products conferring great value to the health of plants and humans. Pueraria lobata, a legume, has long been used in Chinese traditional medicine. (Iso)flavonoids mainly present as glycosyl-conjugates and accumulate in P. lobata roots. However, the molecular mechanism underlying the glycosylation processes in (iso)flavonoid biosynthesis are not fully understood. In the current study, three novel UDP-glycosyltransferases (PlUGT4, PlUGT15, and PlUGT57) were identified in P. lobata from RNA-seq data. Biochemical assays of these three recombinant PlUGTs showed all of them were able to glycosylate isoflavones (genistein and daidzein) at the 7-hydroxyl position in vitro. In comparison with the strict substrate specificity for PlUGT15 and PlUGT57, PlUGT4 displayed utilization of a broad range of sugar acceptors. Particularly, PlUGT15 exhibited a much higher catalytic efficiency toward isoflavones (genistein and daidzein) than any other identified 7-O-UGT from P. lobata. Moreover, the transcriptional expression patterns of these PlUGTs correlated with the accumulation of isoflavone glucosides in MeJA-treated P. lobata, suggesting their possible in vivo roles in the glycosylation process.

Trigonella foenum-graecum L. (fenugreek) is a valuable resource of producing diosgenin which serves as a substrate for synthesizing more than two hundred kinds of steroidal drugs. Phytochemical analysis indicated that methyl jasmonate (MeJA) efficiently induced diosgenin biosynthesis in fenugreek seedlings. Though early steps up to cholesterol have recently been elucidated in plants, cytochrome P450 (CYP)- and glycosyltransferase (GT)-encoding genes involved in the late steps from cholesterol to diosgenin remain unknown. This study established comparative fenugreek transcriptome datasets from the MeJA-treated seedlings and the corresponding control lines. Differential gene expression analysis identified a number of MeJA-induced CYP and GT candidate genes. Further gene expression pattern analysis across a different MeJA-treating time points, together with a phylogenetic analysis, suggested specific family members of CYPs and GTs that may participate in the late steps during diosgenin biosynthesis. MeJA-induced transcription factors (TFs) that may play regulatory roles in diosgenin biosynthesis were also discussed. This study provided a valuable genetic resource to functionally characterize the genes involved in diosgenin biosynthesis, which will push forward the production of diosgenin in microbial organisms using a promising synthetic biology strategy.

The addition of surface functional groups to multi-walled carbon nanotubes (MWCNTs) expands their application in engineering, materials, and life science. In the study, we explored the antifungal activities of MWCNTs with different surface groups against an important plant pathogenic fungi Fusarium graminearum. All of the OH-, COOH-, and NH2-modified MWCNTs showed enhanced inhibition in spore elongation and germination than the pristine MWCNTs. The length of spores decreased by almost a half from 54.5 μm to 28.3, 27.4, and 29.5 μm, after being treated with 500 μg·mL−1 MWCNTs-COOH, MWCNTs-OH, and MWCNTs-NH2 separately. Furthermore, the spore germination was remarkably inhibited by surface-modified MWCNTs, and the germination rate was only about 18.2%, three times lower than pristine MWCNTs. The possible antifungal mechanism of MWCNTs is also discussed. Given the superior antifungal activity of surface modified MWCNTs and the fact that MWCNTs can be mass-produced with facile surface modification at low cost, it is expected that this carbon nanomaterial may find important applications in plant protection.

Polycyclic aromatic compounds (PACs) continue to demand attention due to their widespread presence and well-established health implications. Given that incomplete combustion is a major contributor to PACs and inhalation constitutes a crucial human exposure pathway, a comprehensive understanding of the concentrations, spatial distributions, and fates of a broad range of PACs in the atmosphere is important. Passive air samplers (PASs) are a commonly utilized technique for PAC sampling and monitoring. In this study, we present the results from two one-year calibration experiments, one starting in summer and the other in winter, using a passive air sampler equipped with XAD resin as the sorbent (XAD-PAS). Throughout both experiments, PACs were consistently sorbed during the initial six-month period. However, the sorbed amounts for many PACs exhibited a decrease after half a year of deployment. Three hypotheses to explain this phenomenon were explored, including the uptake of atmospheric particles, evaporation from the sorbent, and reactions with photooxidants. All had to be rejected based on the obtained data, additional laboratory experiments and model results. Model simulations were further used to (i) confirm that a loss process must be invoked to explain the observed uptake behaviour and (ii) estimate the kinetics of that loss process for different PACs. Sampling rates (SRs) for 28 PACs derived from the linearized uptake curves during the first six months of deployment were comparable to those of other semi-volatile organic compounds obtained during the same calibration experiment, and they also demonstrate a consistent negative correlation with volatility. [ABSTRACT FROM AUTHOR]

Under the bad sea conditions and weak Beidou navigation signal environment, it is difficult to locate the ship on the sea, and the Beidou navigation system can't work well. Beidou pseudolite system can improve the performance of Beidou navigation system as a navigation signal transmitter fixed on the ground, the signal of which can improve satellite positioning constellation structure, and improve the system availability reliability and precision. In order to ensure the interoperability and non-correlation of the Beidou pseudolite and the Beidou navigation system, the pseudolite ranging-codes should be selected in the same code space of the satellite ranging-codes and the residual pseudo random code generated by the 2 taps design scheme does not satisfy the performance requirements of the ranging-codes. To solve this issue, a combined design scheme with 3 taps is proposed, and 12 kinds of pseudolite ranging-codes are optimally selected according to the optimum design parameters of ranging-codes. The waveform and correlation of the selected pseudolite ranging-codes are analyzed by MATLAB, the acquisition simulation is carried out by using the new pseudolite ranging-codes. The experimental results show that the new 3-taps based ranging codes design scheme behaves a good balance, correlation and spectral characteristics. [ABSTRACT FROM AUTHOR]