Large Seasonal Variation in Nitrogen Isotopic Abundances of Ammonia Volatilized from a Cropland Ecosystem and Implications for Regional NH3 Source Partitioning.

Ammonia (NH3) volatilization from agricultural lands is a main source of atmospheric reduced nitrogen species (NHx). Accurately quantifying its contribution to regional atmospheric NHx deposition is critical for controlling regional air nitrogen pollution. The stable nitrogen isotope composition (expressed by δ15N) is a promising indicator to trace atmospheric NHx sources, presupposing a reliable nitrogen isotopic signature of NH3 emission sources. To obtain more specific seasonal δ15N values of soil NH3 volatilization for reliable regional seasonal NH3 source partitioning, we utilized an active dynamic sampling technique to measure the δ15N-NH3 values volatilized from maize cropping land in northeast China. These values varied from -38.0 to -0.2‰, with a significantly lower rate-weighted value observed in the early period (May-June, -30.5 ± 6.7‰) as compared with the late period (July-October, -8.5 ± 4.3‰). Seasonal δ15N-NH3 variations were related to the main NH3 production pathway, degree of soil ammonium consumption, and soil environment. Bayesian isotope mixing model analysis revealed that without considering the seasonal δ15N variation in soil-volatilized NH3 could result in an overestimate by up to absolute 38% for agricultural volatile NH3 to regional atmospheric bulk ammonium deposition during July-October, further demonstrating that it is essential to distinguish seasonal δ15N profile of agricultural volatile NH3 in regional source apportionment.

Expression characteristics and their functional role of IGFBP gene family in pan-cancer.

BACKGROUND: Insulin-like growth factor binding proteins (IGFBPs) are critical regulators of the biological activities of insulin-like growth factors. The IGFBP family plays diverse roles in different types of cancer, which we still lack comprehensive and pleiotropic understandings so far. METHODS: Multi-source and multi-dimensional data, extracted from The Cancer Genome Atlas (TCGA), Oncomine, Cancer Cell Line Encyclopedia (CCLE), and the Human Protein Atlas (HPA) was used for bioinformatics analysis by R language. Immunohistochemistry and qRT-PCR were performed to validate the results of the database analysis results. Bibliometrics and literature review were used for summarizing the research progress of IGFBPs in the field of tumor. RESULTS: The members of IGFBP gene family are differentially expressed in various cancer types. IGFBPs expression can affect prognosis of different cancers. The expression of IGFBPs expression is associated with multiple signal transduction pathways. The expression of IGFBPs is significantly correlated with tumor mutational burden, microsatellite instability, tumor stemness and tumor immune microenvironment. The qRT-PCR experiments verified the lower expression of IGFBP2 and IGFBP6 in gastric cancer and the lower expression of IGFBP6 in colorectal cancer. Immunohistochemistry validated a marked downregulation of IGFBP2 protein in gastric cancer tissues. The keywords co-occurrence analysis of IGFBP related publications in cancer showed relative research have been more concentrating on the potential of IGFBPs as tumor diagnostic and prognostic markers and developing cancer therapies. CONCLUSIONS: These findings provide frontier trend of IGFBPs related research and new clues for identifying novel therapeutic targets for various cancers.

RNA-sequencing reveals the expression profiles of tsRNAs and their potential carcinogenic role in cholangiocarcinoma.

BACKGROUND: Recently, the incidence of cholangiocarcinoma (CCA) has gradually increased. As CCA has a poor prognosis, the ideal survival rate is scarce for patients. The abnormal expressed tsRNAs may regulate the progression of a variety of tumors, and tsRNAs is expected to become a new diagnostic biomarker of cancer. However, the expression of tsRNAs is obscure and should be elucidated in CCA. METHODS: High-throughput RNA sequencing technology (RNA-seq) was utilized to determine the overall expression profiles of tsRNAs in three pairs CCA and adjacent normal tissues and to screen the tsRNAs that were differentially expressed. The target genes of dysregulated tsRNAs were predicted and the biological effects and potential signaling pathways of these target genes were explored by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to validate 11 differentially expressed tRFs with 12 pairs CCA and adjacent normal tissues. RESULTS: High-throughput RNA-seq totally demonstrated 535 dysregulated tsRNAs, of which 241 tsRNAs were upregulated, such as tRF-21-YLKZKWE5D，tRF-16-9NF5W8B，tRF-27-78YLKZKWE52，tRF-19-RLXN48KP，tRF-33-IK9NJ4S2I7L7DV，tRF-19-F8DHXYIV, and 294 tsRNAs were downregulated (tRF-20-739P8WQ0, tRF-34-JJ6RRNLIK898HR, tRF-17-VL8RPY5, tRF-23-YP9LON4VDP, tRF-39-EH623K76IR3DR2I2, tRF-17-18YKISM, tRF-19-Q1Q89PJZ, etc.) in CCA compared with adjacent normal tissues (|log2 [fold change] | ≥ 1 and p value <0.05). GO and KEGG enrichment analyses indicated that the target genes of dysregulated tRFs (tRF-34-JJ6RRNLIK898HR, tRF-38-0668K87SERM492V, and tRF-39-0668K87SERM492E2) were mainly enriched in the Notch signaling pathway, Hippo signaling pathway, cAMP signaling pathway and in growth hormone synthesis, secretion and action, etc. qRT-PCR result showed that tRF-34-JJ6RRNLIK898HR/tRF-38-0668K87SERM492V/tRF-39-0668K87SERM492E2 was downregulated (p = 0.021), and tRF-20-LE2WMK81 was upregulated in CCA (p = 0.033). CONCLUSION: Differentially expressed tRFs in CCA are enriched in many pathways associated with neoplasms, which may impact the tumor progression and have potential to be diagnostic biomarkers and therapeutic targets of CCA.

Mature conifers assimilate nitrate as efficiently as ammonium from soils in four forest plantations.

Conifers are considered to prefer to take up ammonium (NH4+ ) over nitrate (NO3- ). However, this conclusion is mainly based on hydroponic experiments that separate roots from soils. It remains unclear to what extent mature conifers can use nitrate compared to ammonium under field conditions where both roots and soil microbes compete for nitrogen (N). We conducted an in situ whole mature tree nitrogen-15 (15 N) labeling experiment (15 NH4+ vs 15 NO3- ) over 15 d to quantify ammonium and nitrate uptake and assimilation rates in four 40-yr-old monoculture coniferous plantations (Pinus koraiensis, Pinus sylvestris, Picea koraiensis and Larix olgensis, respectively). For the whole tree, 15 NO3- contributed 39% to 90% to total 15 N tracer uptake among four plantations during the study period. At day 3, the 15 NO3- accounted for 77%, 64%, 62% and 59% by Larix olgensis, Pinus koraiensis, Pinus sylvestris and Picea koraiensis, respectively. Our study indicates that mature coniferous trees assimilated nitrate as efficiently as ammonium from soils even at low soil nitrate concentration, in contrast to the results from hydroponic experiments showing that ammonium uptake dominated over nitrate. This implies that mature conifers can adapt to increasing availability of nitrate in soil, for example, under the context of globalization of N deposition and global warming.

Dynamics and multi-annual fate of atmospherically deposited nitrogen in montane tropical forests.

The effects of nitrogen (N) deposition on forests largely depend on its fate after entering the ecosystem. While several studies have addressed the forest fate of N deposition using 15 N tracers, the long-term fate and redistribution of deposited N in tropical forests remains unknown. Here, we applied 15 N tracers to examine the fates of deposited ammonium ( NH 4 + ) and nitrate ( NO 3 - ) separately over 3 years in a primary and a secondary tropical montane forest in southern China. Three months after 15 N tracer addition, over 60% of 15 N was retained in the forests studied. Total ecosystem retention did not change over the study period, but between 3 months and 3 years following deposition 15 N recovery in plants increased from 10% to 19% and 13% to 22% in the primary and secondary forests, respectively, while 15 N recovery in the organic soil declined from 16% to 2% and 9% to 2%. Mineral soil retained 50% and 35% of 15 N in the primary and secondary forests, with retention being stable over time. The total ecosystem retention of the two N forms did not differ significantly, but plants retained more 15 NO 3 - than 15 NH 4 + and the organic soil more 15 NH 4 + than NO 3 - . Mineral soil did not differ in 15 NH 4 + and 15 NO 3 - retention. Compared to temperate forests, proportionally more 15 N was distributed to mineral soil and plants in these tropical forests. Overall, our results suggest that atmospherically deposited NH 4 + and NO 3 - is rapidly lost in the short term (months) but thereafter securely retained within the ecosystem, with retained N becoming redistributed to plants and mineral soil from the organic soil. This long-term N retention may benefit tropical montane forest growth and enhance ecosystem carbon sequestration.

Plasmonic micropipe spectral filters in mid-infrared.

Multispectral analyzers based on nanostructured plasmonic spectral filters can potentially find a wide range of applications. However, spectral filters based on the widely reported microhole or ring arrays suffer from relatively wide filtering bands, resulting in a relatively low spectral resolution. In this work, we fabricate high-performance spectral filters based on vertically standing micropipes on a silver film. An infrared spectral microscope is used to investigate the properties of these micropipe spectral filters. The results indicate that the micropipe spectral filters have a full width at half-maximum ∼5 times smaller than the microhole filters at the same wavelength. Micropipe spectral filters are expected to significantly improve the spectral resolution of multispectral analyzers.

Fate of atmospherically deposited NH4+ and NO3- in two temperate forests in China: temporal pattern and redistribution.

The impacts of anthropogenic nitrogen (N) deposition on forest ecosystems depend in large part on its fate. However, our understanding of the fates of different forms of deposited N as well as the redistribution over time within different ecosystems is limited. In this study, we used the 15 N-tracer method to investigate both the short-term (1 week to 3 months) and long-term (1-3 yr) fates of deposited NH4+ or NO3- by following the recovery of the 15 N in different ecosystem compartments in a larch plantation forest and a mixed forest located in northeastern China. The results showed similar total ecosystem retention for deposited NH4+ and NO3- , but their distribution within the ecosystems (plants vs. soil) differed distinctly particularly in the short-term, with higher 15 NO3- recoveries in plants (while lower recoveries in organic layer) than found for 15 NH4+ . The different short-term fate was likely related to the higher mobility of 15 NO3- than 15 NH4+ in soils instead of plant uptake preferences for NO3- over NH4+ . In the long-term, differences between N forms became less prevalent but higher recoveries in trees (particularly in the larch forest) of 15 NO3- than 15 NH4+ tracer persisted, suggesting that incoming NO3- may contribute more to plant biomass increment and forest carbon sequestration than incoming NH4+ . Differences between the two forests in recoveries were largely driven by a higher 15 N recovery in the organic layer (both N forms) and in trees (for 15 NO3- ) in the larch forest compared to the mixed forest. This was due to a more abundant organic layer and possibly higher tree N demand in the larch forest than in the mixed forest. Leachate 15 N loss was minor (<1% of the added 15 N) for both N forms and in both forests. Total 15 N recovery averaged 78% in the short-term and decreased to 55% in the long-term but with increasing amount of 15 N label (re)-redistributed into slow turn-over pools (e.g., trees and mineral soil). The different retention dynamics of deposited NH4+ and NO3- may have implications in environmental policy related to the anthropogenic emissions of the two N forms.

Variations in nitrogen-15 natural abundance of plant and soil systems in four remote tropical rainforests, southern China.

The foliar stable N isotope ratio (δ(15)N) can provide integrated information on ecosystem N cycling. Here we present the δ(15)N of plant and soil in four remote typical tropical rainforests (one primary and three secondary) of southern China. We aimed to examine if (1) foliar δ(15)N in the study forests is negative, as observed in other tropical and subtropical sites in eastern Asia; (2) variation in δ(15)N among different species is smaller compared to that in many N-limited temperate and boreal ecosystems; and (3) the primary forest is more N rich than the younger secondary forests and therefore is more (15)N enriched. Our results show that foliar δ(15)N ranged from -5.1 to 1.3‰ for 39 collected plant species with different growth strategies and mycorrhizal types, and that for 35 species it was negative. Soil NO3 (-) had low δ(15)N (-11.4 to -3.2‰) and plant NO3 (-) uptake could not explain the negative foliar δ(15)N values (NH4 (+) was dominant in the soil inorganic-N fraction). We suggest that negative values might be caused by isotope fractionation during soil NH4 (+) uptake and mycorrhizal N transfer, and by direct uptake of atmospheric NH3/NH4 (+). The variation in foliar δ(15)N among species (by about 6‰) was smaller than in many N-limited ecosystems, which is typically about or over 10‰. The primary forest had a larger N capital in plants than the secondary forests. Foliar δ(15)N and the enrichment factor (foliar δ(15)N minus soil δ(15)N) were higher in the primary forest than in the secondary forests, albeit differences were small, while there was no consistent pattern in soil δ(15)N between primary and secondary forests.

Subsurface wastewater infiltration systems for nitrogen pollution control.

Subsurface wastewater infiltration systems (SWISs) are suggested to be a cost-effective and environmentally friendly method for sewage treatment. However, a comprehensive summary of the relevant mechanisms and optimization methods for nitrogen (N) removal in SWIS is currently lacking. In this review, we first summarize the N transformation mechanisms in SWIS. The impact of operational parameters on the N removal efficiency is then delineated. To enhance pollutant removal and minimize resource wastage, it is advisable to maintain a wet-dry ratio of 1:1 and a hydraulic loading rate of 8-10 cm/day. The organic load should be determined based on influent characteristics to optimize the balance between sewage treatment and nitrous oxide (N2O) emission. Finally, various strategies and modifications have been suggested to enhance pollutant removal efficiency and reduce N2O emissions in SWIS, such as artificial aeration, supply electron donors, and well-designed structures. Overall, greater emphasis should be placed on the design and management of SWIS to optimize their co-benefits while effectively controlling N pollution. PRACTITIONER POINTS: SWISs are often considered black boxes with their efficiency depending on hydraulic characteristics, biological characteristics, and substrate properties. Biological nitrification coupled with denitrification is considered to be the major N removal process. Increasing the reduction of N2O to the inert N2 form is a potential mechanism to mitigate global warming. Strategies such as artificial aeration, supply electron donors, and well-designed structures are suggested to improve N removal performance.

Nitrogen removal performance of improved subsurface wastewater infiltration system under various influent carbon-nitrogen ratios.

Subsurface wastewater infiltration system (SWIS) has been recognized as a simple operation and environmentally friendly technology for wastewater purification. However, effectively removing nitrogen (N) remains a challenge, hindering the widespread application of SWIS. In this study, zero-valent iron (ZVI) and porous mineral material (PMM) were applied in SWIS to improve the soil matrix. Our results suggested that the addition of ZVI and PMM could simultaneously enhance N removal efficiency and reduce nitrous oxide emissions. This could be attributed to the abundant electrons generated by ZVI alleviating the electronic limitation of denitrification and the porous structure of PMM providing solid phase support for microbial growth. In addition, the abundance of microbial functional genes increased in modified SWIS, which could further explain the higher pollutant removal efficiency. Overall, this study provides new insights into the mitigation of wastewater pollution and greenhouse gas emissions in SWIS. PRACTITIONER POINTS: ZVI and PMM can adapt to different C loads and enhance pollutant removal efficiency in SWIS. Increasing C-N ratios positively affected the nitrate removal performance and negatively affected ammonium removal performance in SWIS. The amending soil matrix promoted the reduction of the N2 O to N2 and greenhouse gas emissions were well controlled. The abundance of microbial functional genes increased with the improvement of the soil matrix.

Mechanical performance study of PVA fiber-reinforced seawater and sea sand cement-based composite materials.

Due to the swift progress in the construction sector, there is a global concern about the potential scarcity of river sand and freshwater resources. The development of new construction materials is considered an inevitable trend for industry growth. PVA fibers, known for their strong corrosion resistance, cost-effectiveness, and high toughness, have the potential to enhance the corrosion resistance and seismic performance of structures in marine environments. However, their mechanical properties and durability in the seawater and sea sand environment are not well understood. Therefore, the investigation of the impact of seawater and sea sand on the mechanical properties and durability of PVA fiber-reinforced cement composites is considered crucial. A mechanical performance analysis of PVA fiber-reinforced seawater and sea sand fiber cement composites was conducted in this study. PVA fiber volume fractions of 0%, 0.75%, and 1.5%, cement composite matrix strength grades of C30 and C50, and curing periods of 28 days, 90 days, and 180 days were examined, investigating their influence on the bending toughness of PVA fiber-reinforced seawater and sea sand cement composites. Specific conclusions include the addition of fibers increased the peak bending load, had a less corrosive effect in seawater, and improved the flexural toughness of the material. The most significant improvement was observed at 1.5% fiber content, where the load-deflection curve was fuller and the energy absorption capacity of the material increased by 33-109%, maintaining good bending toughness. Furthermore, higher fiber contents are required for high-strength cementitious composites to improve flexural toughness and durability. The formulation of calculation formulas for predicting bending strength and corresponding deflection, which fit well with the experimental results; and the development of a calculation model for the bending toughness index of PVA fiber-reinforced seawater and sea sand cement composites, providing an effective prediction of material bending toughness.

Transformation mechanisms of ammonium and nitrate in subsurface wastewater infiltration system: Implication for reducing greenhouse gas emissions.

Subsurface wastewater infiltration system (SWIS) has been recognized as a cost-effective and environmentally friendly tool for wastewater treatment. However, there is a lack of knowledge on the transformation processes of nitrogen (N), hindering the improvement of the N removal efficiency in SWIS. Here, the migration and transformation mechanisms of ammonium (NH4+-N) and nitrate (NO3+-N) over 10 days were explored by 15N labeling technique. Over the study period, 49% of the added 15NH4+-N remained in the soil, 29% was removed via gaseous N emissions, and 14% was leaked with the effluent in the SWIS. In contrast, only 11% of the added 15NO3--N remained in the soil while 65% of the added 15NO3--N was removed via gaseous N emissions, and 12% with the effluent in the SWIS. The main pathway for N2O emission was denitrification (52-70%) followed by nitrification (15-28%) and co-denitrification (9-20%). Denitrification was also the predominant pathway for N loss as N2, accounting for 88-96% of the N2 emission. The dominant biological transformation processes were different at divergent soil depths, corresponding to nitrification zone and denitrification zone along the longitudinal continuum in SWIS, which was confirmed by the expression patterns of microbial gene abundance. Overall, our findings reveal the mechanism of N transformation in SWIS and provide a theoretical basis for establishing a pollutant management strategy and reducing greenhouse gas emissions from domestic wastewater treatment.

Ticks (Acari: Ixodidae) infesting cattle in coastal Kenya harbor a diverse array of tick-borne pathogens.

Ticks and the microbes they transmit have emerged in sub-Saharan Africa as a major threat to veterinary and public health. Although progress has been made in detecting and identifying tick-borne pathogens (TBPs) across vast agroecologies of Kenya, comprehensive information on tick species infesting cattle and their associated pathogens in coastal Kenya needs to be updated and expanded. Ticks infesting extensively grazed zebu cattle in 14 villages were sampled and identified based on morphology and molecular methods and tested for the presence of bacterial and protozoan TBPs using PCR with high-resolution melting analysis and gene sequencing. In total, 3,213 adult ticks were collected and identified as Rhipicephalus appendiculatus (15.8%), R. evertsi (12.8%), R. microplus (11.3%), R. pulchellus (0.1%), Amblyomma gemma (24.1%), A. variegatum (35.1%), Hyalomma rufipes (0.6%), and H. albiparmatum (0.2%). Ticks were infected with Rickettsia africae, Ehrlichia ruminantium, E. minasensis, Theileria velifera and T. parva. Coxiella sp. endosymbionts were detected in the Rhipicephalus and Amblyomma ticks. Co-infections with two and three different pathogens were identified in 6.9% (n = 95/1382) and 0.1% (n = 2/1382) of single tick samples, respectively, with the most common co-infection being R. africae and E. ruminantium (7.2%, CI: 4.6 - 10.6). All samples were negative for Coxiella burnetii, Anaplasma spp. and Babesia spp. Our study provides an overview of tick and tick-borne microbial diversities in coastal Kenya.

Microbial-Related Metabolites May Be Involved in Eight Major Biological Processes and Represent Potential Diagnostic Markers in Gastric Cancer.

Metabolites associated with microbes regulate human immunity, inhibit bacterial colonization, and promote pathogenicity. Integrating microbe and metabolome research in GC provides a direction for understanding the microbe-associated pathophysiological process of metabolic changes and disease occurrence. The present study included 30 GC patients with 30 cancerous tissues and paired non-cancerous tissues (NCs) as controls. LC-MS/MS metabolomics and 16S rRNA sequencing were performed to obtain the metabolic and microbial characteristics. Integrated analysis of the microbes and metabolomes was conducted to explore the coexistence relationship between the microbial and metabolic characteristics of GC and to identify microbial-related metabolite diagnostic markers. The metabolic analysis showed that the overall metabolite distribution differed between the GC tissues and the NC tissues: 25 metabolites were enriched in the NC tissues and 42 metabolites were enriched in the GC tissues. The α and ß microbial diversities were higher in the GC tissues than in the NC tissues, with 11 differential phyla and 52 differential genera. In the correlation and coexistence integrated analysis, 66 differential metabolites were correlated and coexisted, with specific differential microbes. The microbes in the GC tissue likely regulated eight metabolic pathways. In the efficacy evaluation of the microbial-related differential metabolites in the diagnosis of GC, 12 differential metabolites (area under the curve [AUC] >0.9) exerted relatively high diagnostic efficiency, and the combined diagnostic efficacy of 5 to 6 microbial-related differential metabolites was higher than the diagnostic efficacy of a single feature. Therefore, microbial diversity and metabolite distribution differed between the GC tissues and the NC tissues. Microbial-related metabolites may be involved in eight major metabolism-based biological processes in GC and represent potential diagnostic markers.

Effect of increased carbon load on denitrification efficiency and nitrate isotope enrichment factors in subsurface wastewater infiltration system.

Denitrification plays a dominant role in nitrate removal in subsurface wastewater infiltration system (SWIS). However, the effect of increased carbon (C) load on denitrification efficiency in the SWIS remain unclear. In this study, we used analyses of stable isotopes of nitrogen (N) and oxygen (O) in nitrate to investigate the N and O isotope enrichment factors (15 ε and 18 ε) and quantified N losses via denitrification in SWIS. The results demonstrated that an increase in C loads positively affected the pollutant removal performance of SWIS. The natural abundance of 15 N and 18 O increased with decreasing nitrate concentration from 12.5 to 7.3 mg/L, accompanied by increased 15 ε and 18 ε from -8.7‰ to -10.6‰ and -5.9‰ to -8.2‰, respectively, as the C load increased from 18 to 36 g/(m2  d). The contribution of denitrification to nitrate removal was 62%, 71%, and 77% when C loads were 18, 27, and 36 g/(m2  d), respectively, indicating that increased C loads could improve the nitrate removal through denitrification in SWIS. PRACTITIONER POINTS: Increasing C loads positively affected the nitrate removal performance of SWIS. N and O isotope enrichment factors of nitrate increased with the enhancement of influent C load. A C load of 36 g/(m2 d) is recommended in SWIS to improve the N removal performance and denitrification efficiency.

Ultrasensitive determination of α-glucosidase activity using CoOOH nanozymes and its application to inhibitor screening.

In this work, a novel method for the colorimetric sensing of α-glucosidase (α-Glu) activity was developed based on CoOOH nanoflakes (NFs), which exhibit efficient oxidase-mimicking activity. Colorless 3,3',5,5'-tetramethylbenzidine (TMB) can be oxidized by CoOOH NFs into blue-colored oxidized TMB (oxTMB) in the absence of H2O2. L-Ascorbic acid-2-O-α-D-glucopyranose (AAG) can be hydrolysed by α-glucosidase to produce ascorbic acid, resulting in a significant decrease of catalytic activity of CoOOH NFs. Thus, a colorimetric α-glucosidase activity detection method was designed with a limit of detection of 0.0048 U mL-1. Furthermore, the designed sensing platform exhibits favorable applicability for the α-glucosidase (α-Glu) activity assay in real samples. Meanwhile, this method can be expanded to study the inhibitors of α-Glu. Finally, the as-proposed method combined with a smartphone would be a color recognizer, which was successfully applied for the determination of α-Glu activity in human serum samples.

Numerical Studies on Failure Mechanisms of All-Composite Sandwich Structure with Honeycomb Core under Compression and Impact Loading Conditions.

The all-composite sandwich structure with the honeycomb core is a lightweight and high-strength structure with broad application scenarios. The face sheet and honeycomb core of the proposed all-composite sandwich structure in this work are composed of carbon-fiber-reinforced polymer (CFRP) composites. The mechanical response and damage mechanism of the all-composite sandwich structure under out-of-plane quasi-static compression and out-of-plane impact are studied by numerical methods. The refined finite element models of the sandwich structures are built on the ABAQUS/Explicit platform. The micromechanics of failure (MMF) theory based on physical component failure is used to describe the intralaminar damage mechanism of the face sheet and honeycomb core, and the mixed-mode exponential cohesive zone model (ECZM) is utilized to simulate the initiation and evolution of interlayer damage. In addition, the cohesive contact approach is adopted to capture the debonding failure at the face-sheet/core. The numerical results show that the all-composite sandwich structure has the characteristics of large structural stiffness and strong energy absorption ability. The failure mechanism of the all-composite sandwich structure under compression is mainly matrix damage and delamination of the honeycomb core, with buckling and folding in appearance. Under out-of-plane impact, matrix damage and delamination arise on the upper sheet, little damage is observed on the lower sheet, and the delamination damage morphology tends to be circular with increasing impact energy. In addition, the interface failure of the upper-sheet/core is more than that of the lower-sheet/core. In addition, the matrix damage near the impact center of the honeycomb core tends to be consistent with the delamination contour, and a small amount of fiber failure is also observed, which manifests as a collapse morphology of the impact area. The research results enrich the understanding of the mechanical behavior of all-composite sandwich structures with honeycomb cores and provide theoretical support for their potential applications.

Comprehensive Analysis and Validation of Solute Carrier Family 25 (SLC25) and Its Correlation with Immune Infiltration in Pan-Cancer.

As the largest gene family functioning in protein transport among human solute carriers, the SLC25 family (mitochondrial carrier family) can participate in development of cancer. However, a comprehensive exploration for the exactly roles of SLC family remains lacking. In the present study, a total of 15 functional SLC25 family genes were retrieved from all current publications. And multidimensional analyses were systematically performed based on the transcriptome and genome data of SLC25 family from a variety of online databases for their expression, immune cell infiltration, and cancer prognosis. Validation by qPCR and immunohistochemistry were further conducted for the expression of partial SLC25 family members in some tumor tissue. We found that the SLC25 family had strong correlation with immune cells, such as macrophages M2, CD8+ T cell, CD4+ T cell memory activated, and memory resting. Among them, SLC25A6 was most correlated with Macrophage M1 in uveal melanoma (r = -0.68, P = 1.9e - 0.5). Expression of mRNA level showed that SLC25A4 was downregulated in stomach adenocarcinoma and colon adenocarcinoma. SLC25A7 was highly expressed in stomach adenocarcinoma and colon adenocarcinoma. SLC25A23 was decreased in colon adenocarcinoma. qPCR and immunohistochemistry validation results were consistent with our bioinformatics prediction. SLC25A8 was associated with the prognosis of cancer. All these findings suggested that the SLC25 family might affects the immune microenvironment of the cancer and then had the potential to be predictive biomarkers for early diagnosis and prognosis as well as novel targets for individualized treatment of cancer.

Epidemiology of tick-borne pathogens of cattle and tick control practices in coastal Kenya.

Tick-borne diseases (TBD) are a major constraint to livestock health and productivity in sub-Saharan Africa. Nonetheless, there are relatively few robust epidemiologic studies documenting TBD and its management in different endemic settings in Kenya. Therefore, a cross-sectional study using multi-stage cluster sampling was undertaken to characterize the epidemiology of TBD and management factors among zebu cattle reared under an extensive system in coastal Kenya. Blood samples from 1486 cattle from 160 herds in 14 villages were screened for the presence of tick-borne bacterial and protozoan pathogens using PCR with high-resolution melting analysis and sequencing. Standardized questionnaires were used to collect data on herd structure and herd management practices, and a mixed-effect logistic regression model to identify risk factors for tick-borne pathogens (TBPs). The application of chemical acaricide was the primary method for tick control (96.3%, 154/160), with the amidine group (mainly Triatix®, amitraz) being the most frequently used acaricides. Respondents identified East Coast fever as the most important disease and Butalex® (buparvaquone) was the most commonly administered drug in response to perceived TBD in cattle. The overall animal- and herd-level prevalence for TBPs were 24.2% (95% confidence interval (CI): 22.0-26.4%) and 75.6% (95% CI: 68.2-82.1%), respectively. Cattle were infected with Anaplasma marginale (10.9%, 95% CI: 9.4-12.6), Theileria parva (9.0%, 95% CI: 7.5-10.5), Anaplasma platys (2.6%, 95% CI: 1.9-3.6), Theileria velifera (1.1%, 95% CI: 0.7-1.8), Babesia bigemina (0.5%, 95% CI: 0.2-1.0), and Anaplasma sp. (0.1%, 95% CI: 0.0-0.4). Moreover, 21 cattle (1.4%) were co-infected with two TBPs. None of the assessed potential risk factors for the occurrence of either A. marginale or T. parva in cattle were statistically significant. The intra-herd correlation coefficients (lCCs) computed in this study were 0.29 (A. marginale) and 0.14 (T. parva). This study provides updated molecular-based information on the epidemiological status of TBPs of cattle and herd management practices in coastal Kenya. This information can be used in designing cost-effective control strategies for combating these TBD in the region.

Retention of deposited ammonium and nitrate and its impact on the global forest carbon sink.

The impacts of enhanced nitrogen (N) deposition on the global forest carbon (C) sink and other ecosystem services may depend on whether N is deposited in reduced (mainly as ammonium) or oxidized forms (mainly as nitrate) and the subsequent fate of each. However, the fates of the two key reactive N forms and their contributions to forest C sinks are unclear. Here, we analyze results from 13 ecosystem-scale paired 15N-labelling experiments in temperate, subtropical, and tropical forests. Results show that total ecosystem N retention is similar for ammonium and nitrate, but plants take up more labelled nitrate ([Formula: see text]%) ([Formula: see text]) than ammonium ([Formula: see text]%) while soils retain more ammonium ([Formula: see text]%) than nitrate ([Formula: see text]%). We estimate that the N deposition-induced C sink in forests in the 2010s  is [Formula: see text] Pg C yr-1, higher than previous estimates because of a larger role for oxidized N and greater rates of global N deposition.