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Highlights from the article: Stem and branch N concentrations exhibited upward trends, and leaf Nutrient stress stimulates leaf N resorption. NRE [N N N] 1 Upward trend, while leaf N concentration showed a down- Figure 4: nitrogen resorption efficiency of leaves, roots, branches.

Aims The productivity of forest plantations in temperate areas is often limited by nitrogen (N), but may shift towards phosphorus (P) limitation with increasing atmospheric N deposition. Nutrient resorption is a nutrient conservation strategy in plants. Although data on nutrient resorption are available for overstory trees, there are few data for understory vegetation. Methods We examined leaf N and P concentrations and N and P resorption efficiencies (NRE and PRE, respectively) in eight understory species in 11- and 45-year-old Larix principis-rupprechtii stands subjected to N supplementation over a 3-year period. Important findings Leaf N concentrations and N:P ratios increased and P concentrations decreased, with N input in species within the 45-year-old stand, but not in the 11-year-old stand. NRE and PRE were not altered by N input in any of the species in either stand, but N resorption proficiency decreased and P resorption proficiency increased, in the species in the 45-year-old stand. Thus, the growth of understory species may be more P-limited in the 45- versus 11-year-old stand, and nutrient resorption proficiency was more sensitive to N addition than nutrient resorption efficiency. These results will improve the understanding of nutrient use strategies and their responses to N addition in understory vegetation. The contrasting effects of N addition on nutrient status between stand ages cannot be ignored when modeling ecosystem nutrient cycling under global N deposition conditions. [ABSTRACT FROM AUTHOR]

Porcine circovirus type 3 (PCV3) was initially reported in 2016 in the United States of America. Since then, the virus has been detected on swine farms in Poland, South Korea, and China using PCR. However, a serological survey of PCV3 in pig populations has never been conducted. In this study, for the first time, we established an indirect enzyme-linked immunosorbent (ELISA) assay and performed a national retrospective serological survey for PCV3. Our results showed that the PCV3-postive rate increased from 22.35% to 51.88% between 2015 and 2017. The above results suggest PCV3 has spread widely in China with increased positive rates since 2015. [ABSTRACT FROM AUTHOR]

Objective Methods Results Interpretation Human T‐cell leukemia virus type 1‐associated myelopathy (HAM) is a chronic, progressive, inflammatory disease with unclear pathogenesis and no effective treatments. We aimed to investigate a novel mechanistic theory and treat HAM patients with rituximab, which can deplete CD20+ B lymphocytes in circulation.Single‐cell RNA sequencing (scRNA‐seq) data was analyzed to identify HTLV‐1‐associated B cells and their effect on T cells. An observational analysis of our HAM cohort was conducted to elucidate changes in the immunological microenvironment of these patients. Peripheral blood mononuclear cells (PBMC) from HAM patients were isolated to explore the efficacy of B cell depletion in vitro. To assess the effect of B‐cell depletion on HAM patients, eligible participants in our cohort received rituximab therapy (NCT04004819).ScRNA‐seq results suggest a significant effect of HTLV‐1‐associated B cells on T cells. Additionally, HTLV‐1 was found to infect B cells and depletion of B cells inhibited the proliferation of T cells. Number of B cells in HAM patients had positive correlation with the proviral load and infected cell counts. Depletion of B cells led to a reduction in HTLV‐1 proviral load in vitro. Furthermore, in clinical trial, 14 HAM patients were enrolled. Three patients (21.4%) who received rituximab failed to achieve remission, compared to 24 (85.7%) patients received any other therapy that failed to achieve remission. With a low level of circulating B cells, the proportion of Ki67‐positive cells in CD4+ T cells fell.This study provided evidence that depleting B‐lymphocytes is an innovative strategy for treating patients with HAM and broadens the understanding of the role of B cells in infectious immunity. [ABSTRACT FROM AUTHOR]

Multifloroside (4), together with 10-hydroxyoleoside 11-methyl ester (1), 10-hydroxyoleoside dimethyl ester (2), and 10-hydroxyligustroside (3), are all secoiridoids, which are naturally occurring compounds that possess a wide range of biological and pharmacological activities. However, the anti-cancer activity of 1–4 has not been evaluated yet. The objective of this work was to study the anti-cancer activities of 1–4 in the human epidermoid carcinoma cell lines A431 and the human non-small cell lung cancer (NSCLC) cell lines A549. The results indicate that 1–4 differ in potency in their ability to inhibit the proliferation of human A431 and A549 cells, and multifloroside (4) display the highest inhibitory activity against A431 cells. The structure-activity relationships suggest that the o-hydroxy-p-hydroxy-phenylethyl group may contribute to the anti-cancer activity against A431 cells. Multifloroside treatment can also inhibit cell colony formation, arrest the cell cycle in the S-phase, increase the levels of reactive-oxygen-species (ROS), and mitochondrial membrane potential (MMP), but it did not significantly induce cell apoptosis at low concentrations. The findings indicated that multifloroside (4) has the tendency to show selective anti-cancer effects in A431 cells, along with suppressing the colony formation, inducing S cell cycle arrest, ROS production, and increasing MMP. [ABSTRACT FROM AUTHOR]

In this paper, a light-weight radio frequency fingerprinting identification (RFFID) scheme that combines with a two-layer model is proposed to realize authentications for a large number of resource-constrained terminals under the mobile edge computing (MEC) scenario without relying on encryption-based methods. In the first layer, signal collection, extraction of RF fingerprint features, dynamic feature database storage, and access authentication decision are carried out by the MEC devices. In the second layer, learning features, generating decision models, and implementing machine learning algorithms for recognition are performed by the remote cloud. By this means, the authentication rate can be improved by taking advantage of the machine-learning training methods and computing resource support of the cloud. Extensive simulations are performed under the IoT application scenario. The results show that the novel method can achieve higher recognition rate than that of traditional RFFID method by using wavelet feature effectively, which demonstrates the efficiency of our proposed method. [ABSTRACT FROM AUTHOR]

Canine parvovirus-2 (CPV-2) infection causes serious multisystemic disease in dogs and many animal species worldwide. Previously, a monoclonal antibody (MAb) of CPV-2, 10H4, showed high neutralizing activity and therapeutic effect against CPV-2 in dogs. However, the application of mouse MAb is limited in other animals due to immune rejection. Here, the variable regions of the heavy and light chains of 10H4 were cloned and ligated with constant canine antibody regions to produce a canine-derived chimeric MAb 11D9, in a CHO-S cell expression system. The cell supernatant of the CHO cell line 11D9 exhibited a HI titer of 1:2560 against all the variants of CPV-2 (new CPV-2a, new CPV-2b, and CPV-2c), and had the same average neutralization titer as the new CPV-2a (1:11,046.5) and new CPV-2b (1:11,046.5) variants, which was slightly higher than that of CPV-2c variants (1:10,615.7). In animal experiment, the treatment of chimeric MAb 11D9 had a high therapeutic effect in beagles infected with the new CPV-2a. Overall, the canine-derived chimeric MAb 11D9 produced by CHO-S cells showed a high HI and neutralization titer against CPV-2 and the therapeutic effects against the new CPV-2a in beagles, providing potential for the prevention or treatment of CPV-2 infections in dogs. Key points: A canine-derived chimeric MAb 11D9 was produced by CHO cell lines. The MAb 11D9 exhibited high HI and neutralization titers against new CPV-2 variants. The MAb 11D9 had a high therapeutic effect in beagles infected with the new CPV-2a variant. [ABSTRACT FROM AUTHOR]

The 15N:14N ratio (δ15N) is often used as an integrated indicator of nitrogen (N) status in natural terrestrial ecosystems. However, the mechanisms by which long-term N addition affects N cycling and status in temperate plantations with different ages remain poorly understood. Here, we used an approach of leaf–soil continuum of δ15N with the combination of incubation experiments to evaluate the effects of three rates of decadal N addition (urea) on N status in young, intermediate, and mature larch (Larix principis-rupprechtii) plantations in northern China. We found that leaf δ15N decreased significantly from 1.6‰ in young trees to −0.5‰ and −1.0‰ in intermediate and mature trees, respectively, due to increases in the use of NO– 3-N relative to NH+ 4-N with stand age, and probably a shift in N acquisition from mineral soil in the young plantation to organic and/or surface mineral soil layers in the intermediate and mature plantations. Decadal N addition decreased leaf δ15N, which was likely to be due to the direct imprints of 15N-depleted urea input, the inhibition of soil net mineralization, and nitrification, and greater dependence on N absorption by ectomycorrhizal fungi after N addition. Soil δ15N decreased with stand age, which was likely to be due to reduced soil N transformation (e.g., mineralization) and/or relative abundance of ectomycorrhizal fungi along the chronosequence; however, soil δ15N was not affected by long-term N inputs. Combined with the decreased enrichment factor (ε = δ15N leaf – δ15N soil), these results suggest a shift from more open N cycling (potentially greater ecosystem N losses) in young plantation to more closed N cycling (facilitation of ecosystem N retention) in mature plantation, which showed negative response to decadal N addition. These findings provide new insights into N acquisition strategies and cycling in the typically N-limited temperate plantations under heightened atmospheric N deposition. • δ15N with soil incubation were used in three larch plantations under decadal N input. • With the growth of larch individuals, they increasingly prefer to absorb NO– 3-N. • Soil N transformations were negatively affected by decadal N addition. • N cycling shifted from open in young to closed in intermediate and mature plantation. • Decedal N addition elicited negative impacts on N cycling of larch plantations. [ABSTRACT FROM AUTHOR]

Given the adverse effects of the current principal treatments, there is still a great need for effective cures for rheumatoid arthritis (RA), an immune-mediated disease. Toddalia asiatica (L.) Lam is a traditional medicinal herb that can be used for RA treatment because of its anti-inflammatory and analgesic properties. To investigate the possible effects of Toddalia asiatica extract (TAE) on intestinal immunity and the intestinal bacterial flora in a rat model of RA. The anti-arthritis effect of TAE was evaluated in arthritis rats induced by complete Freund's adjuvant-induced arthritis (AIA). Arthritis index (AI) scores, systemic inflammation scores, histopathologic changes in the colon and ankle were detected by hematoxylin and eosin staining. Western blot analysis was performed to assess the protein expression of IL-17A, RORC, IL-1β, IL-6, FOXP3, IL-10 in the colon. RT-PCR was performed to assess the expression of the colon's mRNA. Finally, changes to the gut microbiome by sequencing 16S rDNA. Microbial function prediction was performed using PICRUSt with the KEGG databases and correlation analysis was carried out by computing Spearman's rank correlations. demonstrated that TAE administration at a dose of 3 g/kg dramatically decreased AI scores, systemic inflammation scores, and histopathologic lesions of the ankle and colon in AIA rats. TAE was found to significantly reduce the expression levels of Th17-related proteins and mRNAs (IL-17A, RORC, IL-1β and IL-6) in the colon, while increasing the expression levels of Treg-related proteins and mRNA (IL-10 and FOXP3), which helped restore the balance of Th17/Treg immune cells in the colon. Meanwhile, TAE was also found to be capable of remodeling the gut microbiota in AIA rats. Depleting RA-associated genera and thereby increasing α-diversity enriched the gut microbiota's diversity and shifted the community composition dramatically, leading to the increase of Firmicutes_unclassified , Ruminococcaceae_unclassified , Muribaculum , Subdoligranulum , Lachnospira , Marvinbryantia , and the reduction of RA-related bacteria Ligilactobacillus , Streptococcus and Eubacterium-eligens-group. Furthermore, PICRUSt analysis revealed that metabolic pathways were associated with TAE treatment, with metabolic pathways dominating. Among them, metabolic pathways were predominant. Correlation studies showed that a total of 9 microorganisms, including Ligilactobacillus , Eubacterium-eligens-group and Subdoligranulum , were significantly associated with Th17/Treg expression. This study demonstrates that TAE is a low-toxicity poly alkaline drug that can rapidly and effectively improve joint symptoms in RA rats and increases beneficial intestinal bacteria and decreases harmful ones, which is associated with modulating Th17/Treg interactions in intestinal T cells and reversing microbial disorders. [Display omitted] • TAE successfully ameliorated RA and colonic inflammation. • Pathogenesis of RA based on gut microbial homeostasis with TAE was first studied. • TAE may provide a good candidate for anti-RA treatment options. [ABSTRACT FROM AUTHOR]

• Simple but efficient method to prepare peanut-like multimodal theranostic nanoplatform. • "Triple-responsive" and synergetic strategy achieves the effect of 1 + 1 ≥ 2. • Specific drugs release and high drug accumulation in tumor tissues. • Excellent multimodal imaging and high-sensitivity chemo-photodynamic therapy. It is of great importance to develop tumor microenvironment (TME) responsive and adjustable theranostic nano-systems for specific and efficient cancer treatment. However, carrier-based nanomedicines are often inefficacious in vivo due to low drug-loading efficiency, lack of synergistic effects, poor targeting specificity and limited drug accumulation in tumor tissues. Herein, we report a new multimodal theranostic nanoplatform which is assembled from Fe 3 O 4 nanoclusters, MnO 2 nanosheets with multifunctional and cross-linked polyphosphazene. This peanut-like nanoplatform exhibited enhanced chemo/photodynamic therapy (CT/PDT) effect as well as significant tumor-targeting capacity. In addition, Fe 3 O 4 cores and MnO 2 nanoshells enables T 1 / T 2 magnetic resonance imaging (MRI) of tumor tissues, while photosensitizer methylene blue (MB) allows for fluorescence imaging and PDT simultaneously. Importantly, nanopeanut agents could dual-regulate intracellular oxygen and glutathione (GSH) levels in TME by MnO 2 shells, to relieve hypoxic condition and produce enough ROS to induce cell apoptosis. Our research demonstrated that the multistage TME-responsive nanoplatform is ideally suitable for tumor specific drug delivery and real-time disease tracking with enhanced theranostic properties. [ABSTRACT FROM AUTHOR]

Herein, a photoinduced direct C(sp 2 )-H alkylation of N -heteroaromatics by using commercially available tetrabutylammonium tribromide (TBATB) as a HAT reagent is described. The method uses O 2 as the oxidant, and features metal-free, mild reaction conditions and good functional group compatibility.

Difluoromethylated heterocyclic compounds have found broad applications in numerous bioactive molecules. Herein, we report photoredox catalysis-induced direct C-H difluoromethylation of heterocycles by using bis(difluoromethyl) pentacoordinate phosphorane (PPh 3 (CF 2 H) 2 , 1 ) as the reagent. A variety of heterocycles, such as quinoxalin-2(1 H )-one, thiophene, indole, and coumarin, are readily tailored with a difluoromethyl group. The method is featured as transition-metal-free by using an organic compound Erythrosin B as the catalyst and O 2 as the oxidant.

Fast and accurate frequency estimation is significant for instrumentation and measurement. A sinusoid frequency estimator using discrete Fourier transform (DFT) is presented. DFT is implemented on the sinusoid and the maximum DFT bin is sought out to obtain the coarse estimate. Different from all the existing methods, two asymmetric discrete-time Fourier transform (DTFT) samples situated at arbitrary positions on the same side of the maximum DFT bin are employed to get the fine estimate. The theoretical mean square error is analyzed. To evaluate the estimation performance, the presented estimator is compared with the Cramer-Rao lower bound (CRLB) and state-of-art estimators through computer simulations. Simulation results demonstrate that the presented algorithm is closer to the CRLB compared with the competing methods when the signal-to-noise ratio (SNR) varies in a large range and is unbiased at high SNR., (© 2023 Author(s). Published under an exclusive license by AIP Publishing.)