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Amphotericin B (AmB) is a powerful but toxic fungicide that operates via enigmatic small molecule–small molecule interactions. This mechanism has challenged the frontiers of structural biology for half a century. We recently showed AmB primarily forms extramembranous aggregates that kill yeast by extracting ergosterol from membranes. Here, we report key structural features of these antifungal ‘sponges’ illuminated by high-resolution magic-angle spinning solid-state NMR, in concert with simulated annealing and molecular dynamics computations. The minimal unit of assembly is an asymmetric head-to-tail homodimer: one molecule adopts an all-trans C1–C13 motif, the other a C6–C7-gauche conformation. These homodimers are staggered in a clathrate-like lattice with large void volumes similar to the size of sterols. These results illuminate the atomistic interactions that underlie fungicidal assemblies of AmB and suggest this natural product may form biologically active clathrates that host sterol guests.

Stroke patients with autonomic dysfunction are more likely to develop cardiac problems, which have been linked to lower functional outcomes and increased mortality. In this study, heart rate variability (HRV) detection paired with the Clinical Feature Scale will be utilized to elucidate the immediate impact of manual acupuncture on autonomic dysfunction of varying severity in the convalescence stroke phase. This is a randomized, single-blind, controlled clinical trial approach. At a ratio of 1:1, 60 appropriate patients will be randomly randomized into either the experimental or control group. On the basis of symptomatic treatment drugs, the experimental group will additionally undertake acupuncture therapy 3 times a week for 4 weeks, for a total of 12 times. Primary outcomes include 24-hour HRV and 60-minute HRV detection at week 4 compared with baseline. The secondary outcome is the score of clinical feature scale at week 4 compared with the baseline. Adverse events and safety indices will be recorded throughout the experiment. The SPSS V.25.0 statistical program was applied for analysis, and measurement data were expressed as mean ± SD.

Ponding at the soil surface exerts profound impacts on infiltration. However, the effects of ponding depth on infiltration, especially the development of a saturated zone below the soil surface, have not been considered in present infiltration models. A new general Green-Ampt model solution (GAMS) was derived for a one-dimensional vertical infiltration into soils under a uniform initial moisture distribution with ponding on its surface. An expression was included in the new solution for simulating the saturated layer developed below the soil surface as long as the pressure head at the surface is greater than the water-entry suction. The GAMS simulates the infiltration processes closer to the numerical solution by HYDRUS-1D than the traditional and a recently improved Green-Ampt model. Moreover, an inversion method to improve the estimates of soil hydraulic parameters from one-dimensional vertical infiltration experiments that is based on the GAMS was suggested. The effect of ponding depth (hp), initial soil moisture content, soil texture, and hydraulic soil properties (Ks, hd and n) in the saturated zone was also evaluated. The results indicate that the saturated zone developed at a much faster rate than the unsaturated zone during infiltration. Generally, a larger saturated zone was found for soils with higher initial soil moisture content, coarser texture, higher Ks values and lower hd and n. Our findings reveal that including the saturated zone in the infiltration model yields a better estimate for the soil hydraulic parameters. The proposed GAMS model can improve irrigation design and rainfall-runoff simulations.

Objective: Bacteria-induced mastitis is characterized by mammary pain, swelling of the mammary glands, and decreased milk production and quality in cows. Reducing the negative effects of inflammation is a challenge, and the regulatory mechanism of the inflammatory response in mammary epithelial cells is not yet clear. Results: Our results indicated that the RNA-binding protein Musashi2 (Msi2) regulates the inflammatory response and the blood-milk barrier in mastitis. Msi2 is commonly enriched in stem cells and tumor cells. We found that Msi2 expression was upregulated during mastitis. Silencing Msi2 in BMECs and mice increased inflammatory factors and tight junctions. Transcriptional profiling analysis revealed that Msi2 silencing increased transforming growth factor-beta (TGFβ) signaling. RNA-interacting protein immunoprecipitation assays demonstrated that Msi2 could affect the translation of transforming growth factor-beta receptor 1 (TGFβR1), thereby affecting TGFβ signaling. Overall, Msi2 silencing reduced inflammatory reactions and repaired the blood-milk barrier during mastitis Conclusions: Our findings indicate that Msi2 plays an important role in mastitis by regulating the TGFβ signaling pathway. A decrease in Msi2 can reduce the negative effects of mastitis by inhibiting the expression of inflammatory factors and increasing tight junction proteins.

Artificial cyanophages are considered to be an effective biological method to control harmful cyanobacterial bloom. However, no synthetic cyanophage genome has been constructed and where its obstacles are unclear. Here, we survey a stretch of 16 kb length sequence of cyanophage A-4L that is unclonable in

Background The pathogenesis of neck pain in the brain, which is the fourth most common cause of disability, remains unclear. Furthermore, little is known about the characteristics of dynamic local functional brain activity in cervical pain. Objective The present study aimed to investigate the changes of local brain activity caused by chronic neck pain and the factors leading to neck pain. Methods Using the amplitude of low-frequency fluctuations (ALFF) method combined with sliding window approach, we compared local brain activity that was measured by the functional magnetic resonance imaging (fMRI) of 107 patients with chronic neck pain (CNP) with that of 57 healthy control participants. Five pathogenic factors were selected for correlation analysis. Results The group comparison results of dynamic amplitude of low-frequency fluctuation (dALFF) variability showed that patients with CNP exhibited decreased dALFF variability in the left inferior temporal gyrus, the middle temporal gyrus, the angular gyrus, the inferior parietal marginal angular gyrus, and the middle occipital gyrus. The abnormal dALFF variability of the left inferior temporal gyrus was negatively correlated with the average daily working hours of patients with neck pain. Conclusions The findings indicated that the brain regions of patients with CNP responsible for audition, vision, memory, and emotion were subjected to temporal variability of abnormal regional brain activity. Moreover, the dALFF variability in the left inferior temporal gyrus might be a risk factor for neck pain. This study revealed the brain dysfunction of patients with CNP from the perspective of dynamic local brain activity, and highlighted the important role of dALFF variability in understanding the neural mechanism of CNP.

Atmospheric emission sources of persistent organic pollutants (POPs) in China's eastern seaboard regions cause heavy POP contamination in the Bohai Sea (BS), China. Because many rivers are emptying into the BS, terrestrial runoff has been considered a dominant pathway of POPs onto the BS. Here, we explored the contribution of atmospheric transport and terrestrial runoff to organophosphorus flame retardants (OPFRs) to the BS by using an atmospheric transport model and a terrestrial runoff model. We examined the sensitivity and response of OPFR in the BS seawater to its atmospheric transport, deposition, and riverine discharge via terrestrial runoff. Both terrestrial runoff and atmospheric transport model simulations reveal that the atmospheric transport and deposition, including dry, wet, and diffusive gaseous deposition, dominate OPFR input into the BS. The total OPFR fluxes entering the BS via the atmospheric pathway and riverine input were 70.4 and 2.8 t/yr in 2013, respectively.

With the completion of the draft assembly of the giant panda genome sequence, RNA sequencing technology has been widely used in genetic research on giant pandas. We used RNA-seq to examine black and white hair follicle samples from adult pandas. By comparison with the giant panda genome, 75 963 SNP loci were labeled, 2426 differentially expressed genes (DEGs) were identified, and 2029 new genes were discovered, among which 631 were functionally annotated. A cluster analysis of the DEGs showed that they were mainly related to the Wnt signaling pathway, ECM-receptor interaction, the p53 signaling pathway, and ribosome processing. The enrichment results showed that there were significant differences in the regulatory networks of hair follicles with different colors during the transitional stage of hair follicle resting growth, which may play a regulatory role in melanin synthesis during growth. In conclusion, our results provide new insights and more data support for research on the color formation in giant pandas.

We report a type of core@dotted-shell structured nanoprobe that incorporates water-soluble silica and water-interacted gadolinium oxide, endowed with excellent hydrophilicity and high magnetic reso...

Amphotericin-like glycosylated polyene macrolides (GPMs) are a clinically and industrially important family of natural products, but the mechanisms by which they exert their extraordinary biological activities have remained unclear for more than half a century. Amphotericin B exerts fungicidal action primarily via self-assembly into an extramembranous sponge that rapidly extracts ergosterol from fungal membranes, but it has remained unclear whether this mechanism is applicable to other GPMs. Using a highly conserved polyene–hemiketal region of GPMs that we hypothesized to represent a conserved ergosterol-binding domain, we bioinformatically mapped the entirety of the GPM sequence-function space and expanded the number of GPM biosynthetic gene clusters (BGCs) by 10-fold. We further leveraged bioinformatic predictions and tetrazine-based reactivity screening targeting the electron-rich polyene region of GPMs to discover a first-in-class methyltetraene- and diepoxide-containing GPM, kineosporicin, and to assign BGCs to many new producers of previously reported members. Leveraging a range of structurally diverse known and newly discovered GPMs, we found that the sterol sponge mechanism of fungicidal action is conserved., A combination of genome-mining and chemical reactivity identified new antifungal natural products. Such glycosylated polyene macrolides share a common mode of action via ergosterol extraction.

Accurate determination of evapotranspiration (ET) has tremendous potential in guiding irrigation and improving the efficiency of water resources utilization in the North China Plain. Eddy covariance (EC) method is currently a popular method for determining field-scale ET. However, due to varying foot print and unclosed energy balance, the applicability of EC in different regions needs to be tested and corrected. In present work, we compared the ET of the winter wheat – summer maize rotation cropland measured by the EC method with the ET measured by large-scale lysimeters on different time scales. The degree of energy balance closure of EC measurements in this region is 78%. After adjusted by using Bowen ratio forced closure method, the ET monitored by EC is comparable with those monitored by large-scale lysimeters. The results also indicated that the consistency of the observed ET by the EC and lysimeters got better with an increasing time scale, especially for the multi-year average ET values with a relative deviation of less than 1%. The short-time events such as irrigation and precipitation and the mismatch of the varying footprint area of the EC and the small fixed source area of the lysimeter should be responsible for the discrepancy of ET in two methods on daily scale. However, the factors of crop biomass, total available water, and local climate condition exert more effects on the observed ET on large time scale. Overall, the EC technique is responsible for ET measurement of winter wheat – summer maize rotation cropland of the North China Plain.

Major problems in China’s pursuit of sustainable agricultural development include inadequate, low-quality soil and water resources, imbalanced regional allocation and unreasonable utilization of resources. In some regions, overexploitation of soil resources and excessive use of chemicals triggered a web of unforeseen consequences, including insufficient use of agricultural resources, agricultural non-point source pollution and land degradation. In the past decade, China has changed its path of agricultural development from an output-oriented one to a modern, sustainable one with agricultural ecological civilization as its goal. First, the government has formulated and improved its laws and regulations on soil resources and the environment. Second, the government has conducted serious actions to ensure food safety and coordinated management of agricultural resources. Third, the government has planned to establish national agricultural high-tech industry demonstration zones based on regional features to strengthen the connection among the government, agri-businesses, scientific community and the farming community. As the next step, the government should improve the system for ecological and environmental regulation and set up a feasible eco-incentive mechanism. At the same time, the scientific community should strengthen the innovation of bottleneck technologies and the development of whole solutions for sustainable management in ecologically fragile regions. This will enhance the alignment between policy mechanisms and technology modes and effectively promote the sustainable development of agriculture in China.

We study the weak radiative decays of ${\bf B}_b \to {\bf B}_n \gamma$ with ${\bf B}_{b(n)} $ the anti-triplet-bottom (octet) baryons in the light front quark model. We obtain that ${\cal B}(\Lambda_b \to \Lambda \gamma)= (7.1 \pm 0.3 )\times 10 ^{-6}$, which agrees well with the current experimental value of $(7.1 \pm 1.7 )\times 10 ^{-6}$. We predict that ${\cal B}(\Xi_b^0 \to \Xi^0 \gamma)= (1.0 \pm 0.1 )\times 10 ^{-5}$ and ${\cal B}(\Xi_b^- \to \Xi^- \gamma) = (1.1 \pm 0.1) \times 10^{-5}$, which are consistent with the latest upper limits set by the LHCb collaboration. In addition, we find that the $SU(3)_F$ flavor symmetry breaking effects for the modes related to the $b\to d \gamma$ transition can be as large as $20\%$., Comment: 16 pages, 1 figure

Specific and cost-effective methodologies for human papillomavirus (HPV) gene detection are significant for clinical diagnosis and cancer control. Herein, a label-free and fluorimetric/colorimetric dual-mode sensing strategy was developed for the quantitative determination of HPV DNA based on the integration of fluorescent DNA-silver nanoclusters (DNA/AgNCs) and G-quadruplex/hemin DNAzyme. The fluorimetric sensing strategy was based on the phenomena that the fluorescence enhancement of DNA/AgNCs obtained in proximity of guanine-rich DNA sequences and the photoinduced electron transfer (PET) effect between the electron donor (DNA/AgNCs) and electron receptor (G-quadruplex/hemin). The colorimetric sensing strategy was relied on the peroxidase-like activity of G-quadruplex/hemin DNAzyme. By integrating DNA/AgNCs and DNAzyme, this dual-mode strategy could produce two independent signals to improve the analytical diversity and accuracy. Under optimized conditions, the fluorimetry and colorimetry of the strategy displayed a linear range of 0.01-4 and 0.02-4 nM, with the low detection limit of 2.3 and 5.2 pM, respectively. Additionally, this dual-mode strategy has been successfully applied to HPV DNA analysis in different real samples with excellent results. Moreover, the sensing platform could be developed for different HPVs DNA assay by only adjusting the recognition sequence, which provided a universal strategy for various kinds of virus analysis.

Wheat (Triticum aestivum L.) cultivars vary in their resistance to Fusarium head blight (FHB), while it is poorly understood how different cultivars influence FHB-causing Fusarium graminearum abundance in rhizosphere soil. A field experiment was conducted to investigate the influence of three wheat cultivars on FHB index, rhizosphere soil F. graminearum abundance, chemical properties, and microbial community composition and metabolic profiles. The cultivars were Sumai3 (SM), Yangmai13 (YM), and Annong8455 (AN), representing high, intermediate, and low resistance to FHB, respectively. Both wheat FHB index and rhizosphere F. graminearum abundance were ranked as SM

Reducing the applications of mineral phosphorus (P) fertilizers and supplementing them by organic fertilizers is becoming a necessary practice in the North China Plain due to overuse of mineral P fertilizers and improper disposal of organic wastes. Knowledge is needed about how the long-term substitution of mineral fertilizers by organic fertilizers affects soil P forms in order to understand soil P transformation and crop P uptake. In this study, we used solution 31P nuclear magnetic resonance (NMR) spectroscopy to characterize P forms in fluvo-aquic soil after 26 years of different fertilization management strategies, organic compost (OM), half compost in combination with half mineral fertilizer NPK (1/2 OM), mineral fertilizer NPK (NPK), mineral fertilizer NK (NK), and an unfertilized control (CK). Results showed that the P extraction efficiency using NaOH-EDTA varied from 13.0 to 27.7% for the soils of the treatments. 31P NMR spectra indicated that the majority of P was in the form of orthophosphate for all the treatments, which constituted 64.3–83.5% of the total extracted P. The application of P fertilizers significantly increased the concentrations of orthophosphate, monoesters and diesters regardless of the P fertilization method, although the proportions of monoesters and diesters were higher in CK. The proportions and concentrations of orthophosphate significantly decreased when all mineral fertilizers were replaced by compost. There was no significant difference in the proportions and concentrations of total organic P, corrected monoesters and diesters in NaOH-EDTA extracts of soils among NPK, 1/2OM and OM treatments. Decreasing mineral P fertilizers and partly replacing them by organic fertilizer in fluvo-aquic soil might increase soil test (Olsen) P and crop P uptake through the degradation of applied organic P forms.

Ammonia oxidizers are key players in the global nitrogen cycle, yet little is known about their ecological performances and adaptation strategies for growth in saline terrestrial ecosystems. This study combined (13)C-DNA stable-isotope probing (SIP) microcosms with amplicon and shotgun sequencing to reveal the composition and genomic adaptations of active ammonia oxidizers in a saline-sodic (solonetz) soil with high salinity and pH (20.9 cmol(c) exchangeable Na(+) kg(−1) soil and pH 9.64). Both ammonia-oxidizing archaea (AOA) and bacteria (AOB) exhibited strong nitrification activities, although AOB performed most of the ammonia oxidation observed in the solonetz soil and in the farmland soil converted from solonetz soil. Members of the Nitrosococcus, which are more often associated with aquatic habitats, were identified as the dominant ammonia oxidizers in the solonetz soil with the first direct labeling evidence, while members of the Nitrosospira were the dominant ammonia oxidizers in the farmland soil, which had much lower salinity and pH. Metagenomic analysis of “Candidatus Nitrosococcus sp. Sol14”, a new species within the Nitrosococcus lineage, revealed multiple genomic adaptations predicted to facilitate osmotic and pH homeostasis in this extreme habitat, including direct Na(+) extrusion/H(+) import and the ability to increase intracellular osmotic pressure by accumulating compatible solutes. Comparative genomic analysis revealed that variation in salt-tolerance mechanisms was the primary driver for the niche differentiation of ammonia oxidizers in saline-sodic soils. These results demonstrate how ammonia oxidizers can adapt to saline-sodic soil with excessive Na(+) content and provide new insights on the nitrogen cycle in extreme terrestrial ecosystems.

Herein, a ratiometric fluorescent nanoprobe was strategically fabricated using pH-sensitive azamonardine (Aza) as a pH indicator and pH-insensitive AIZS QDs as a reference fluorescence signal for urea activity determination and pH sensing. As the pH changed from 9.7 to 11.7, the resorcinol could react with dopamine to form the cyclization product (Aza), producing a fluorescence signal at 455 nm. Meanwhile, the fluorescence intensity of AIZS QDs at 566 nm remained unchanged. Thus, the ratio of the fluorescence intensity (F

Herein, nitrogen-doped copper nanosheet (CuT@N NS) was obtained by pyrolysis of the tryptophan-based Cu-containing nanosheet (CuT NS) and graphitic carbon nitride (g-C

Chemotherapy against the neglected tropical disease visceral leishmaniasis (VL) is suboptimal with only four licensed drugs. Amphotericin B (AmB), despite its toxicity, remained a second line drug for a long time. However, the demonstration that liposomal AmB is highly effective against VL propelled it, despite its cost, to a first line drug in many countries. While several ongoing efforts are aiming at finding cheaper and stable AmB-formulations, an alternative strategy is the development of less-toxic AmB derivatives. We show here that two less-toxic AmB derivatives with the carboxylate at position 16 of AmB derivatized to a methyl urea (AmB-MU) or amino urea (AmB-AU) are active in vitro against Leishmania donovani, both as free-living parasites as well as their intracellular form. Both less-toxic derivatives, similarly to AmB, target the ergosterol pathway of L. donovani. While the AmB-AU derivative showed female-specific liver toxicity in vivo, the AmB-MU derivative was well-tolerated and more effective than AmB against experimental VL. These studies are an important step for improving AmB-based therapy against a prevalent parasitic disease.

In this paper, we proposed a dual-signal fluorometric and colorimetric system based on silicon quantum dots (SiQDs) and 4-nitrophenol (4-NP) for pH and urease sensing. SiQDs with fluorescence emission of 460 nm were prepared via aqueous-phase synthesis. As the pH of the system gradually increased, the absorption band of 4-NP at 400 nm increased and a color reaction from colorless to yellow occurred. The absorption of 4-NP overlapped quiet well with the fluorescence excitation spectrum of SiQDs, which can effectively quench the fluorescence of SiQDs. Therefore, the change of fluorescence and absorption intensities could be used to quantify pH value. The fluorometric and colorimetric pH-sensing systems both exhibited a linear respond to pH ranging from 6.0 to 7.8 with an interval of 0.2 pH unit. Urease could specifically hydrolyze urea to generate carbon dioxide and ammonia, causing an obvious increase of the pH value. Thus, urease could also be detected quantitatively by the above dual-signal pH sensing system. The linear ranges of the fluorometric and colorimetric methods for urease detection were both 2–40 U L-1. The limits of detection were 1.67 and 1.07 U L-1, respectively. More importantly, this established dual-signal system has been successfully exploited in the detection of urease in real samples with satisfactory recoveries. Compared with other traditional single-signal assay strategies, the results obtained by dual-signal methods are more accurate and reliable.

The promotion and use of passive building can effectively promote the modernization of the construction industry and alleviate the increasingly severe environmental and energy crisis. Based on this, the evolutionary game theory is used to establish an evolutionary game model between government and consumers, and the game strategies of both sides are analyzed, the influence of system equilibrium stability and parameters on the stability of evolutionary game is discussed. The dynamic evolution game law of government and consumers based on passive building demand incentive is studied under the premise of limited rationality and fuzzy trust. Then the game trajectory between stakeholders is simulated by MATLAB software, the effects of parameters and initial intention on the evolution process and results are analyzed. It clearly clarifies the dynamic mechanism of the impact of government incentives on behavioral strategies for consumers to buy passive building. It shows that the passive building demand incentive work is focused on government, and the initial intention of government and consumers will directly affect the behavior strategies of both parties. Aiming at the demand incentives of passive building, the corresponding countermeasures and suggestions are proposed at the three levels of awareness, cost control and income.

To investigate the effects of long-term fertilization on microbial decomposition of residues and priming effect (PE), 13C-labeled maize (Zea mays L.) residues were supplied to arable soils with a 20-year application of compost (COM), mineral NPK fertilizer (NPK), or without any treatments, the no-fertilizer control (NF). The soils that had been stored for 6 years were used in the present incubation experiment. The release of CO2–C and the microbial incorporation of residue-derived C determined by phospholipid fatty acids (PLFAs) analysis were monitored over a 90-day incubation period. Residue additions significantly increased cumulative CO2–C emission and induced positive PE. Cumulative residue-derived CO2-C emission and PE mainly occurred within the first 15 days. The COM soil had significantly higher cumulative residue-derived CO2–C emission but lower PE than the NF and NPK soils. Residue additions significantly increased microbial abundance and changed the composition of main microbial groups. The COM soil showed a significantly lower relative fungal abundance (mol%) but a higher relative actinomycetes abundance than the NF and NPK soils. The incorporation of residue-derived C within fungi was the highest among all the main microbial groups and decreased from 15 to 45 days, while the incorporation of residue-derived C within actinomycetes increased with time in three soils. The incorporation of residue-derived C within fungi was the highest in the COM soil over the course of incubation. The long-term compost input promoted fungal use of residue C and stimulated residue decomposition.

Field decomposition of wheat and maize straws was monitored for 20 months using litterbag method in Calcaric Fluvisol soils with three different textures (sand, sandy loam, and silty clay). Residual straw samples were collected at 0 or after 4, 6, 10, and 20 months of decomposition. The chemical structure of straw was analyzed by solid-state 13C nuclear magnetic resonance (13C-NMR) spectroscopy, and the composition of main microbial groups was evaluated by phospholipid fatty acid analysis. Regardless of the straw type and soil texture, the straw biomass and C loss increased steadily in the first 10 months and then leveled off in the following 10 months; both the chemical structure of straw and the composition of main microbial groups differed during incubation. During the first 4 months of wheat straw degradation, the decrease in di-O-alkyl and O-alkyl C and the increase in alkyl and N-alkyl/methoxyl C contents were related to the enrichment of fungi (18:1ω9c) and Gram-negative bacteria (18:1ω7c and 16:1ω7c), while the degradation of maize straw was associated with the decrease in the fungal (18:1ω9c) abundance and the increase in the abundance of Gram-negative (18:1ω7c and 16:1ω7c) and Gram-positive (a15:0) bacteria. During the 6–10-month period, the decrease in di-O-alkyl and O-alkyl C and the increase in alkyl, aryl, and carboxyl/amide C contents were related to the enrichment of arbuscular mycorrhizal fungi (AMF) (16:1ω5c) and Gram-negative (cy19:0ω8c) bacteria and the decrease in fungal (18:2ω6,9c) abundance, with AMF playing an important role in the degradation of both straw types. The altered chemical structure of wheat and maize straws had opposite links with fungal abundance during the first 4 months, while alterations occurring during the 6–10-month period mainly depended on the variation in the AMF abundance.

The leaves of Aster glehni Fr. Schm. (Asteraceae) have been used to treat insomnia in Korea. Insomnia is a common adverse effect of therapeutic agents for Alzheimer's disease (AD), and the control of sleep disturbance may prevent dementia. We hypothesized that the leaves of A. glehni can attenuate cognitive dysfunctions observed in AD. We observed the ameliorating effects of the ethanolic extract of leaves of A. glehni (AG-D) on memory dysfunction through the Morris water maze test, the passive avoidance test, and the Y-maze test. We performed acetylcholinesterase (AChE) activity assay and Western blotting to determine the mechanism of action of AG-D. AG-D significantly attenuated memory dysfunction observed in the above behavior studies and inhibited the activity of AChE. AG-D also increased the levels of phosphorylation extracellular signal-regulated kinase (ERK), cAMP response element-binding protein (CREB), phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), and glycogen synthase kinase 3β (GSK-3β) and the expression levels of brain-derived neurotrophic factor (BDNF) in the hippocampi. These results suggest that AG-D ameliorates memory impairments by AChE inhibition and activation of ERK-CREB-BDNF and PI3K-Akt-GSK-3β signaling pathways. Taken together, this study suggests that AG-D could be used as a potential treatment for cognitive dysfunction.

Humic substances (HS) are vital to soil fertility and carbon sequestration. Using multiple cross-polarization/magic-angle spinning (multiCP/MAS) NMR combined with dipolar dephasing, we quantitatively characterized humic fractions, i.e., fulvic acid (FA), humic acid (HA), and humin (HM), isolated from two representative soils (upland and paddy soils) in China under six long-term (>20 years) fertilizer treatments. Results indicate that each humic fraction showed chemical distinction between the upland and paddy soils, especially with much greater aromaticity of upland HMs than of paddy HMs. Fertilizer treatment exerted greater influence on chemical natures of upland HS than of paddy HS, although the effect was less than that of soil type. Organic manure application especially decreased the percentages of aromatic C in the upland HAs and HMs compared with the control. We concluded that humic fractions responded in chemical nature to environmental conditions, i.e., soil type/cropping system/soil aeration and fertilizer treatments.

The ability of soil microorganisms to uphold a variety of ecosystem services is of increasing interest, but our understanding of the linkage between cropland ecosystem services and the soil microbiome under long-term different fertilizer regimes is still limited. Here, we measured 15 response variables commonly used as indicators of cropland ecosystem services, and employed a shotgun metagenomic sequencing technology to determine microbiome taxonomic composition and functional composition in a sandy loam soil amended with organic and inorganic fertilizers for 28 years. Long-term application of fertilizers had overall positive effects on the variables that indicate soil C and nutrient status, organic material decomposition, nutrient transformation, and plant productivity, but the strength of these effects differed between organic and inorganic fertilization. In long term, organic fertilizers significantly increased the abundance of Sphingomonas and Acidobacteria as well as genes involved in C and N metabolism and degradation of aromatic organic compounds. The observed differences in the indicators of overall biological activity, litter decomposition, nutrient transformation, cropland fertility and productivity were associated with changes in taxonomic composition and functional composition of the soil microbiome. Network analysis revealed that soil organic C, total N, L-leucine aminopeptidase, phosphatase, microbial biomass C and N, and the multifunctionality index showed strong positive associations with Acidobacterium, Lysobacter and Nitrososphaera. These microbes are implicated in the decomposition of organic material, soil C and N transformation, and plant growth promotion. The present study deepens our understanding of the relationship between the soil microbiome and agro-ecosystem functioning, and provides support for the use of organic fertilization strategy to enhance multiple ecosystem services in croplands.

In this paper we investigate the carpetlike structures in the photoelectron momentum distributions (PMDs) of hydrogen atom driven by a linear polarization laser with different optical cycle numbers and an elliptical polarization laser with different ellipticity values. We find that for linear polarization with the optical cycle number nc = 3, the ionized electrons undergo few half cycles, the carpetlike structures in the PMDs are not clearly seen. As the optical cycle number increases, the carpetlike structure becomes more obvious because that the contribution from the constructive and destructive interference. For elliptical polarization laser pulses, the ionized electrons are accelerated along the perpendicular direction along the other elliptical axis. And then the electrons have a spiral movement, which destroys the conditions resulting in the constructive and destructive interference. So the carpetlike structures gradually disappear with the increasing of ellipticity values.

This study aims to investigate the presence of aggregate hierarchy during the decomposition of rice straw in a subtropical soil (Ultisol) with large quantities of Fe and Al oxides and in two temperate soils with a large amount of montmorillonite (Vertisol) or with less organic matter but a large content of CaCO3 (Inceptisol) and to explore the relationship between relative contributions of biotic and abiotic processes in soil aggregation and the presence of aggregate hierarchy. A 120-day incubation experiment with or without 13C-labeled straw was conducted in the above-mentioned three soils previously sieved at

The present study determined the dynamic changes of bacterial community structures and its metabolism functions in rice straw composting process with different types of biochar addition. Results showed that both wheat and maize straw biochar addition greatly increased the temperatures and germination index. Biochar addition influenced microbial community structure and metabolic characteristics of the compost. Firmicutes, Actinobacteria and Proteobacteria were the dominant phyla throughout the process, and both biochar addition significantly increased the relative abundance of Actinobacteria phylum, especially genus Saccharomonospora. The abundance of bacterial genes related to amino acid metabolism, carbohydrate metabolism and energy metabolism were also increased with biochar addition. Moreover, total nitrogen was strongly affected by biochar addition and had the greatest influence on the bacterial community structure. These results indicated that biochar addition improved the maturity and fertility of the compost product as well as significantly regulated the microbial community structure and functions during composting process.

Fertilizer management influences the accumulation of soil organic C and N in agricultural soils. The combined use of chemical and organic fertilizers is considered a good method to enhance soil fertility, but it is still unclear about the effects of substituting manure for fertilizer on aggregation and aggregate associated organic C and N. We selected a 4-yr-old soil fertility experiment to examine the aggregation and aggregate associated organic C and N in response to substituting manure for fertilizer. In comparison to control, no fertilizer added (CK); substituting manure for fertilizer significantly increased organic C and N by 11.61 to 47.97% and 21.05 to 32.63% in 0- to 20-cm bulk soil, respectively. It promoted organic C in the silt + clay fraction, microaggregates, small macroaggregates, and large macroaggregates by 3.17 to 17.15%, 12.94 to 34.09%, 10.99 to 50.20%, and 25.32 to 52.09%, respectively. Aggregate associated N also presented significant increases under substituting manure for fertilizer compared to CK. The mass distribution of small and large macroaggregates were 8.16 to 15.54% and 8.89 to 49.51% higher in the manure-substituted plots than CK, respectively. Organic C and labile C were generally greater in macro- than microaggregates in the manure-substituted plots; redundancy analysis confirmed that macroaggregates had positive effects on organic C and N sequestration in bulk soil and aggregates. Based on these results we suggested that substituting manure increases macroaggregate associated organic C and N, and the formation of small and large macroaggregates is accelerated by organic amendment in the test soil compared to CK.