Nitrogen addition alleviates the adverse effects of drought on plant productivity in a temperate steppe.

Drought and nitrogen enrichment could profoundly affect the productivity of semiarid ecosystems. However, how ecosystem productivity will respond to different drought scenarios, especially with a concurrent increase in nitrogen availability, is still poorly understood. Using data from a 4-year field experiment conducted in a semiarid temperate steppe, we explored the responses of aboveground net primary productivity (ANPP) to different drought scenarios and nitrogen addition, and the underlying mechanisms linking soil properties, plant species richness, functional diversity (community-weighted means of plant traits, functional dispersion) and phylogenetic diversity (net relatedness index) to ANPP. Our results showed that completely excluding precipitation in June (1-month intense drought) and reducing half the precipitation amount from June to August (season-long chronic drought) both significantly reduced ANPP, with the latter having a more negative impact on ANPP. However, reducing half of the precipitation frequency from June to August (precipitation redistribution) had no significant effect on ANPP. Nitrogen addition increased ANPP irrespective of drought scenarios. ANPP was primarily determined by soil moisture and nitrogen availability by regulating the community-weighted means of plant height, rather than other aspects of plant diversity. Our findings suggest that precipitation amount is more important than precipitation redistribution in influencing the productivity of temperate steppe, and nitrogen supply could alleviate the adverse impacts of drought on grassland productivity. Our study advances the mechanistic understanding of how the temperate grassland responds to drought stress, and implies that management strategies to protect tall species in the community would be beneficial for maintaining the productivity and carbon sequestration of grassland ecosystems under climate drought.

Soft-in-Rigid Strategy Promoting Rapid and High-Capacity Lithium Storage by Chemical Scissoring.

Large and rapid lithium storage is hugely demanded for high-energy/power lithium-ion batteries; however, it is difficult to achieve these two indicators simultaneously. Sn-based materials with a (de)alloying mechanism show low working potential and high theoretical capacity, but the huge volume expansion and particle agglomeration of Sn restrict cyclic stability and rate capability. Herein, a soft-in-rigid concept was proposed and achieved by chemical scissoring where a soft Sn-S bond was chosen as chemical tailor to break the Ti-S bond to obtain a loose stacking structure of 1D chain-like Sn1.2Ti0.8S3. The in situ and ex situ (micro)structural characterizations demonstrate that the Sn-S bonds are reduced into Sn domains and such Sn disperses in the rigid Ti-S framework, thus relieving the volume expansion and particle agglomeration by chemical and physical shielding. Benefiting from the merits of large-capacity Sn with an alloying mechanism and high-rate TiS2 with an intercalation mechanism, the Sn1.2Ti0.8S3 anode offers a high specific capacity of 963.2 mA h g-1 at 0.1 A g-1 after 100 cycles and a reversible capacity of 250 mA h g-1 at 10 A g-1 after 3900 cycles. Such a strategy realized by chemical tailoring at the structural unit level would broaden the prospects for constructing joint high-capacity and high-rate LIB anodes.

Metabolic profiles of Fufang Xiling Jiedu capsule in rats by ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry.

Fufang Xiling Jiedu capsule (FXJC), a traditional Chinese medicine that evolved from "Yinqiao Powder", is widely used for the treatment of cold and influenza. However, due to a lack of in vivo metabolism research, the chemical components responsible for the therapeutic effects still remain unclear. Hence, this study aimed to describe the metabolic profiles of the FXJC in rat plasma, urine, and feces. A combined data mining strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was employed and 201 xenobiotics, including 117 prototype components and 84 metabolites were detected. Phenolic acids, flavonoids, triterpenes, and lignans were prominent ingredients absorbed in vivo, and the major metabolic pathways of the detected metabolites were glucuronidation, sulfation, methylation, and oxidation. This is the first systematic study on the metabolism of the FXJC in vivo, providing valuable information for future studies on the efficacy, toxicity, and mechanism of the FXJC.

Iodine-Promoted Oxidative Cyclization of Methyl Azaarenes and α-Amino Ketones for One-Pot Synthesis of 2-Azaaryl-5-aryl Oxazoles.

A high efficiency protocol was developed for the synthesis of 2,5-disubstituted oxazoles via iodine-promoted oxidative domino cyclization. These reactions were performed with readily available methyl azaarenes and α-amino ketones under metal-free conditions. This protocol is a simple method with high functional group compatibility, a wide range of substrates, and excellent yield, providing a new way to synthesize azaarene-attached oxazoles.

MCCMF: collaborative matrix factorization based on matrix completion for predicting miRNA-disease associations.

BACKGROUND: MicroRNAs (miRNAs) are non-coding RNAs with regulatory functions. Many studies have shown that miRNAs are closely associated with human diseases. Among the methods to explore the relationship between the miRNA and the disease, traditional methods are time-consuming and the accuracy needs to be improved. In view of the shortcoming of previous models, a method, collaborative matrix factorization based on matrix completion (MCCMF) is proposed to predict the unknown miRNA-disease associations. RESULTS: The complete matrix of the miRNA and the disease is obtained by matrix completion. Moreover, Gaussian Interaction Profile kernel is added to the miRNA functional similarity matrix and the disease semantic similarity matrix. Then the Weight K Nearest Known Neighbors method is used to pretreat the association matrix, so the model is close to the reality. Finally, collaborative matrix factorization method is applied to obtain the prediction results. Therefore, the MCCMF obtains a satisfactory result in the fivefold cross-validation, with an AUC of 0.9569 (0.0005). CONCLUSIONS: The AUC value of MCCMF is higher than other advanced methods in the fivefold cross validation experiment. In order to comprehensively evaluate the performance of MCCMF, accuracy, precision, recall and f-measure are also added. The final experimental results demonstrate that MCCMF outperforms other methods in predicting miRNA-disease associations. In the end, the effectiveness and practicability of MCCMF are further verified by researching three specific diseases.

Identification and engineering of 32 membered antifungal macrolactone notonesomycins.

Notonesomycin A is a 32-membered bioactive glycosylated macrolactone known to be produced by Streptomyces aminophilus subsp. notonesogenes 647-AV1 and S. aminophilus DSM 40186. In a high throughput antifungal screening campaign, we identified an alternative notonesomycin A producing strain, Streptomyces sp. A793, and its biosynthetic gene cluster. From this strain, we further characterized a new more potent antifungal non-sulfated analogue, named notonesomycin B. Through CRISPR-Cas9 engineering of the biosynthetic gene cluster, we were able to increase the production yield of notonesomycin B by up to 18-fold as well as generate a strain that exclusively produces this analogue.

Effects of aqueous extracts from the rhizome of Pontederia cordata on the growth and interspecific competition of two algal species.

Single and co-culture systems of Microcystis aeruginosa and Scenedesmus obliquus were prepared with different initial algal densities and treated with different concentrations of aqueous extracts from the rhizome of Pontederia cordata to study its inhibitory effect on algal growth and the competitive relationship between these two algal species. The results showed that aqueous extracts could inhibit the growth of M. aeruginosa and S. obliquus, and the inhibition rate of aqueous extracts on the growth of M. aeruginosa was always higher than that of S. obliquus. A Lotka-Volterra competition model revealed that these two algal species can co-exist without the addition of aqueous extracts, and S. obliquus exhibited a stronger ability to compete than that of M. aeruginosa. Meanwhile, the dominant algal species changed with the addition of aqueous extracts regardless of the initial ratios of the two algae. The species ratio of mixed cultures had a strong effect on the interspecific interaction between the two algae. The higher proportion of S. obliquus in the initial proportion of two algae, the stronger competitive ability of S. obliquus when compared with that of M. aeruginosa.

Sumoylation Negatively Regulates CSR1-Dependent Prostate Cancer Cell Death.

BACKGROUND/AIMS: SUMOylation is a dynamic process and reversed by the activity of SUMO-specific proteases (SENPs) family. SENP1, a member of this family, is highly expressed and plays oncogenic roles in diverse cancers including prostate cancer. However, the SENP1-transgenic mice exhibit aberrant transformation of the mouse prostate gland but do not develop cancer. Cellular Stress Response 1 (CSR1) is a tumor suppressor gene and frequently deleted in prostate cancers. Overexpression of CSR1 in prostate cancer cells inhibits colony formation, anchorage-independent growth and induces cell death. METHODS: The relationship between CSR1 and SENP1 were determined by immunoprecipitation-based proteomics screen and verified by GST-pull down assay. In vivo SUMOylation assay was used to detect the direct effect of SENP1 in the regulation of CSR1. Clustered regularly interspaced short palindromic repeats (CRISPR)-based gene editing was used to generate Senp1-/- and CSR1-/- PC3 cells. FACS assay was used to determine the apoptosis ratio of cells after transfection. RESULTS: CSR1 is SUMOylated at K582 and rapid ubiquitinated and degradated in prostate cancer cells. SENP1 interacts with and deSUMOylates CSR1 to prevent its degradation and enhances CSR1-dependent prostate cancer cell death. CONCLUSION: Thus, our data indicates that CSR1 is a critical SUMOylated substrate of SENP1 that might partially explain the controversial roles of SENP1 in prostate cancer development.

Curcumin and dietary polyphenol research: beyond drug discovery.

Numerous natural products available over the counter are commonly consumed by healthy, sub-healthy or ill people for the treatment and prevention of various chronic diseases. Among them, a few dietary polyphenols, including the curry compound curcumin, have been attracting the most attention from biomedical researchers and drug developers. Unlike many so-called "good drug candidates", curcumin and several other dietary polyphenols do not have a single known therapeutic target or defined receptor. In addition, the bioavailability of these polyphenols is usually very low due to their poor absorption in the gut. These recently debated features have created enormous difficulties for drug developers. In this review, I do not discuss how to develop curcumin, other dietary polyphenols or their derivatives into pharmaceutical agents. Instead, I comment on how curcumin and dietary polyphenol research has enriched our knowledge of insulin signaling, including the presentation of my perspectives on how these studies will add to our understanding of the famous hepatic insulin function paradox.

Tolerance mechanism of Triarrhena sacchariflora (Maxim.) Nakai. seedlings to lead and cadmium: Translocation, subcellular distribution, chemical forms and variations in leaf ultrastructure.

Hydroponic experiments were conducted to assess the accumulation, translocation, and chemical forms of lead (Pb) and cadmium (Cd) in the roots, stems, and leaves of Triarrhena sacchariflora seedlings and the associated variation in leaf ultrastructure. The leaves and leaf ultrastructure showed no significant symptoms of toxicity with 0.05 mM Pb or 0.01 mM Cd exposure for 10d. Chlorosis and wilting were observed in leaves when the Pb and Cd concentration was higher than 0.1 and 0.05 mM in the medium, respectively, as demonstrated by severe ultrastructural modifications at higher concentration in the leaves, such as plasmolysis, cell wall detachment, chloroplast swelling, nuclear condensation, and even nuclear fragmentation. The Pb and Cd concentrations in the roots was significantly higher than those in the stems and leaves. This indicated low Pb and Cd translocation from the roots to the aboveground parts. Subcellular distribution analysis showed that the majority of Pb and Cd was bound to the cell wall, especially in the roots, indicating that the cell wall likely constitutes a crucial storage site for Pb and Cd. This mechanism decreases the translocation of Pb and Cd across membranes and is more effective than vacuolar compartmentation. The majority of Pb and Cd exited in form of insoluble Pb/Cd-pectate or -oxalate complexes in the plant. In conclusion, higher concentrations of Pb or Cd induced premature senescence. High Pb and Cd enrichment was observed in the roots, which decreased the translocation of Pb and Cd from the roots to the aboveground tissues. The immobilization of Pb or Cd by the cell wall is important for plant detoxification and can protect protoplasts from Pb or Cd toxicity. Pb and Cd mainly existed in insoluble Pb/Cd-phosphate or -oxalate complexes, exhibiting low activity and thereby limiting symplastic transport and suppressing toxicity.

[Qilin Pills promote testicular spermatogenesis in azoospermia mice].

OBJECTIVE: To investigate the effect of Qilin Pills (QP) in facilitating the recovery of spermatogenic function in azoospermia (AS) mice and to explore its mechanism of regulating testicular spermatogenesis. METHODS: Fifteen 4-week-old male mice were equally randomized into an AS model control, a low-dose QP and a high-dose QP group. The AS model was established in the mice by intraperitoneal injection of busulfan at 35 mg/kg. After modeling, the animals in the low- and high-dose QP groups were treated with Qilin Pills intragastrically at 2 000 and 8 000 mg/kg/d respectively while those in the model control group fed on a normal diet, all for 28 days. Then, all the mice were sacrificed for examination of the ultrastructures of the epididymis and testis by HE staining, detection of the specific markers of spermatogenic, Sertoli and Leydig cells by Western blot, and determination of the expressions of these markers in the testis tissue by immunofluorescence assay. RESULTS: The number of spermatogenic cells in the testis tissue was significantly decreased in the AS model controls, with no spermatozoa in most of the seminiferous tubules in the epididymis (Johnsen's score: 5.2 ± 0.5). In the high-dose QP group, spermatogenic cells were tightly arranged with distinct layers in the seminiferous tubules, with a large number of spermatozoa but no non-sperm cells in the lumens of the epididymis (Johnsen's score: 9.4 ± 0.6). The number of spermatogenic cells in the testis was increased in the low-dose QP group with some spermatozoa in the seminiferous tubules as compared with that in the model control, but lower than in the high-dose group (Johnsen's score: 7.6 ± 0.6). The Johnsen's score was significantly lower in the model control than in the high- and low-dose QP groups (P < 0.01), and higher in the high-dose than in the low-dose QP group (P < 0.05). The expressions of the specific markers of Sertoli cells SCF, BMP4, SYCP3, DMC1 and Ki67 were also remarkably lower in the model control than in the high- and low-dose QP groups (P < 0.01), and higher in the high-dose than in the low-dose QP group (P < 0.05 or P < 0.01). No statistically significant differences were observed among the three groups of mice in the markers of spermatogonial stem cells (SSC) and undifferentiated SSCs UCHL1, STRA8, NGN3 and PLZF3 (P > 0.05). The expressions of the spermatocyte markers DMC1 and SYCP3 were markedly lower in the model control than in the high- and low-dose QP groups (P < 0.05 or P < 0.01), and higher in the high-dose than in the low-dose QP group (P < 0.05 or P < 0.01). The Ki67 fluorescence signals were distributed in the spermatogonia, with a higher intensity in the model control than in the high- and low-dose QP groups. The acrosome marker PNA was found mainly in the seminiferous tubules, with abundant fluorescence signals in the high- and low-dose QP groups but no obvious dot signals in the model controls. CONCLUSIONS: Qilin Pills may contribute to the meiosis of spermatogonia and promote spermatogenesis by improving the function of Sertoli cells in the testis.

Acute and sub-chronic toxicity of Cajanus cajan leaf extracts.

CONTEXT: The leaves of Cajanus cajan (L.) Millsp. (Fabaceae) have diverse bioactivities, but little safety data are reported. OBJECTIVE: This study examines the toxicological profiles of C. cajan leaf extracts. MATERIALS AND METHODS: The leaves were extracted by water or 90% ethanol to obtain water or ethanol extract (WEC or EEC). EEC was suspended in water and successively fractionated into dichloroform and n-butanol extracts (DEC and BEC). Marker compounds of the extracts were monitored by high-performance liquid chromatography (HPLC). Kunming mice were administered with a single maximum acceptable oral dose (15.0 g/kg for WEC, EEC and BEC and 11.3 g/kg for DEC) to determine death rate or maximal tolerated doses (MTDs). In sub-chronic toxicity investigation, Sprague-Dawley rats were orally given WEC or EEC at 1.5, 3.0 or 6.0 g/kg doses for four weeks and observed for two weeks after dosing to determine toxicological symptoms, histopathology, biochemistry and haematology. RESULTS: Flavonoids and stilbenes in the extracts were assayed. In acute toxicity test, no mortality and noted alterations in weight and behavioural abnormality were observed, and the maximum oral doses were estimated as MTDs. In sub-chronic toxicity study, no mortality and significant variances in haematological and biochemical parameters or organ histopathology were observed, but increased kidney weight in 3.0 g/kg WEC- or 3.0 and 6.0 g/kg EEC-treated female rats, and reduced testes and epididymis weight in EEC-treated male rats were recorded. These changes returned to the level of control after recovery period. CONCLUSION: Acute and sub-chronic toxicity of Cajanus cajan leaf extracts was not observed.

[Isolation, culture, and identification of human spermatogonial stem cells].

OBJECTIVE: To isolate, identify and culture human spermatogonial stem cells (SSC) and then obtain purified and enriched human SSCs for research and application. METHODS: We detected the expression of CD90 in the human testis using the immunofluorescence technique and isolated human testicular spermatogenic cells by two-step enzymatic digestion, followed by differential plating and magnetic-activated cell sorting (MACS) with CD90 as an SSC marker. Then we identified the isolated CD90-positive spermatogenic cells by RT-PCR and immunocytochemistry, and meanwhile cocultured them with Sertoli cells in SG medium in vitro. RESULTS: The isolated CD90-positive cells showed a relatively homogeneous characteristic in size and morphology and expressed the genes specific for human SSCs, with high expressions (90.5%) of GFRA1, GPR125, and UCHL1. After coculture with Sertoli cells in the SG medium for 2 weeks, the isolated CD90-positive cells maintained a good activity. CONCLUSION: CD90 can be regarded as a speci- fic marker for human SSCs and used to obtain highly enriched human SSCs by differential plating and MACS. Furthermore, the isolated human SSCs can be cultured in SG medium in vitro.

[Selection of the sites for microsurgical vasoepididymostomy: A report of 56 cases of epididymal obstructive azoospermia].

OBJECTIVE: To explore the prediction of the site for microsurgical vasoepididymostomy (VE) in the treatment of epididymal obstructive azoospermia (OA). METHODS: This study involved 56 infertile men with confirmed OA whose obstruction was suspected to be in the epididymis. Based on their medical history and results of preoperative physical examination and ultrasonography, we predicted the sites for VE. We performed surgical scrotal exploration for the status of epididymal obstruction, conducted palpation and microscopic observation for the epididymal tubules to be anastomosed, and finally decided on the sites for VE by making sure of the presence of motile sperm in the epididymal fluid of the patients. After surgery, we followed up the patients for the rate of pregnancy. RESULTS: All the patients received bilateral scrotal ultrasonography and surgical scrotal exploration, totaling 112 procedures, including 98 VE procedures. The accuracy rate of the predicted sites for VE was 80.5% (153/190) by medical history and physical examination, 80.3% (90/112) based on the results of ultrasonography, and 87.4% (90/103) according to the first selected epididymal tubules. Of the 28 patients followed up for more than 12 months, motile sperm were found in 19 (67.9% ) at 2 to 12 months and spontaneous pregnancies were achieved in 10 (35.7%), all with the anastomotic sites in the corpus or cauda. CONCLUSION: Medical history and physical examination contribute to the selection of anastomotic sites and non-invasive scrotal ultrasonography is effective and practical for positioning epididymal obstruction. The epididymal tubules with motile sperm for anastomosis could be easily obtained from the most dilated ones in indurated epididymides.

Total aglycones from Marsdenia tenacissima increases antitumor efficacy of paclitaxel in nude mice.

Marsdeniae tenacissimae Caulis (MTC) is a Chinese herbal medicine used mainly for treatment of cancer, whose pharmacologically active constituents responsible for its in vivo activity and clinical efficacy have not been clearly elucidated. In this study, total aglycones of MTC (ETA) showed the ability to sensitize KB-3-1, HeLa, HepG2 and K562 cells to paclitaxel treatment. More inspiringly, ETA markedly enhanced the antitumor activity of paclitaxel in nude mice bearing HeLa or KB-3-1 xenografts. Compared to treatment with paclitaxel alone, treatment with combination of paclitaxel and ETA achieved significant reduction in volume and weight of HeLa tumors (p<0.05), and remarkable inhibition to the growth of KB-3-1 tumors (p<10⁻6). ETA was characterized by the presence of a group of tenacigenin B ester derivatives, among which four reference compounds, 11α-O-tigloyl-12ß-O-acetyltenacigenin B, 11α,12ß-di-O-tigloyltenacigenin B, 11α-O-2-methylbutanoyl-12ß-O-tigloyltenacigenin B, and 11α-O-(2-methylbutanoyl)-12ß-O-benzoyltenacigenin B, accounted for 42.14% of the total peak area of 19 detectable components assayed by HPLC. Our study has identified ETA as a promising sensitizer for cancer chemotherapy.

[On-demand versus on-time dosing of tadalafil for erectile dysfunction: a prospective multi-center study].

OBJECTIVE: To evaluate the safety and efficacy of tadalafil on demand and on time in men with erectile dysfunction. METHODS: We conducted a multi-centered randomized controlled study on 120 ED males, who were assigned to take tadalafil at 10 mg/ 20 mg on demand before sexual activity and at the same dose on time twice a week for 8 weeks. Before and at 4 and 8 weeks after treatment, and 1 month after withdrawal, we obtained the scores on IIEF-5, ED Inventory of Treatment Satisfaction (EDITS) and the short form of Psychological and Interpersonal Relationship Scales (SF-PAIRS) , and compared the safety and efficacy of medication between the two groups of patients. RESULTS: Totally, 110 patients accomplished the trial, 56 in the on-time and 54 in the on-demand group. At 4 and 8 weeks of medication and 1 month after withdrawal, the IIEF-5 scores were improved in both the on-time and on-demand groups, even more significantly in the former than in the latter at 8 weeks of treatment (21.6 +/- 2.9 vs 18.5 +/- 1.7) and 1 month after withdrawal (20.9 +/- 2.1 vs 17.9 +/- 2.3) (P < 0.05). The EDITS scores were significantly higher in the on-time than in the on-demand group at 8 weeks of treatment (31.7 +/- 6.9 vs 28.6 +/- 5.8) and 1 month after withdrawal (30.6 +/- 4.7 vs 27.9 +/- 6.5) (P < 0.05). The scores on the sexual self-confidence, spontaneity and time-concern domains of SF-PAIRS were remarkably improved after medication as compared with the baseline (P < 0.05), even more significantly in the on-time than in the on-demand group at 1 month after withdrawal. Both dosing schedules were well tolerated and no significant differences were observed in safety between the two groups. CONCLUSION: On-time dosing of tadalafil is efficacious and well tolerated in the treatment of ED, and has an even better effect than on-demand dosing at 8 weeks of medication and 1 month after withdrawal.

Endangered status and threatened population ecological factors in Salvia daiguii, an endemic species from Hunan, China.

Many species of Salvia have excellent ornamental, culinary, and medicinal values. Salvia daiguii, is an ornamental and highly medicinal perennial herb endemic to the prefecture-level city of Zhangjiajie in Hunan Province, China, with a narrow geographical distribution. However, currently, it has only been assessed as a Critically Endangered species according to the IUCN classification criteria, but its conservation has not yet been studied. This study investigated the distribution and niche characteristics of S. daiguii, and compared the differences in growth, flowering characteristics, and soil nutrients between the wild and ex situ populations. We also analyzed the effects of soil nutrients on plant growth and flowering characteristics. During the survey, we found 274 individuals on a rock approximately 200 m from ZEFR1. Nevertheless, S. daiguii were still restricted in three populations, TNFP, TGM, and ZEFR in Zhangjiajie City, with a total of about 500 plants and less than 250 mature individuals. Our results show that aspects such as adverse environmental conditions, low seedling renewal rate, a lack of soil nutrients, and competition for the characteristic niche of this and other dominant plants in the natural community are the main ecological factors affecting the growth, flowering, and geographic distribution of S. daiguii. Based on the results of field surveys, we recommend that (1) S. daiguii be classified as Critically Endangered C2b and China's List of Plant Species with Extremely Small Populations. (2) Comprehensive conservation strategies were developed, such as the establishment of nature reserves, reintroduction, public education, and institutional development to provide management recommendations related to the conservation of S. daiguii and other endangered plants.

Reduction in precipitation amount, precipitation events, and nitrogen addition change ecosystem carbon fluxes differently in a semi-arid grassland.

The increases in extent and frequency of extreme drought events and increased nitrogen (N) deposition due to global change are expected to have profound impacts on carbon cycling in semi-arid grasslands. However, how ecosystem CO2 exchange processes respond to different drought scenarios individually and interactively with N addition remains uncertain. In this study, we experimentally explored the effects of different drought scenarios (early season extreme drought, 50 % reduction in precipitation amount, and 50 % reduction in precipitation events) and N addition on net ecosystem CO2 exchange (NEE), ecosystem respiration (ER), and gross ecosystem productivity (GEP) over three growing seasons (2019-2021) in a semi-arid grassland in northern China. The growing-season ecosystem carbon fluxes in response to drought and N addition were influenced by inter-annual precipitation changes, with 2019 as a normal precipitation year, and 2020 and 2021 as wet years. Early season extreme drought stimulated NEE by reducing ER. 50 % reduction in precipitation amount decreased ER and GEP consistently in three years, but only significantly suppressed NEE in 2019. 50 % reduction in precipitation events stimulated NEE. Nitrogen addition stimulated NEE, ER, and GEP, but only significantly in wet years. The structural equation models showed that changes in carbon fluxes were regulated by soil moisture, soil temperature, microbial biomass nitrogen (MBN), and the key plant functional traits. Decreased community-weighted means of specific leaf area (CWMSLA) was closely related to the reduced ER and GEP under early season extreme drought and 50 % reduction in precipitation amount. While increased community-weighted means of plant height (CWMPH) largely accounted for the stimulated ER and GEP under 50 % reduction in precipitation events. Our study stresses the distinct effects of different drought scenarios and N enrichment on carbon fluxes, and highlights the importance of soil traits and the key plant traits in determining carbon exchange in this water-limited ecosystem.

Deep Self-Reconstruction Fusion Similarity Hashing for the Diagnosis of Alzheimer's Disease on Multi-Modal Data.

The pathogenesis of Alzheimer's disease (AD) is extremely intricate, which makes AD patients almost incurable. Recent studies have demonstrated that analyzing multi-modal data can offer a comprehensive perspective on the different stages of AD progression, which is beneficial for early diagnosis of AD. In this paper, we propose a deep self-reconstruction fusion similarity hashing (DS-FSH) method to effectively capture the AD-related biomarkers from the multi-modal data and leverage them to diagnose AD. Given that most existing methods ignore the topological structure of the data, a deep self-reconstruction model based on random walk graph regularization is designed to reconstruct the multi-modal data, thereby learning the nonlinear relationship between samples. Additionally, a fused similarity hash based on anchor graph is proposed to generate discriminative binary hash codes for multi-modal reconstructed data. This allows sample fused similarity to be effectively modeled by a fusion similarity matrix based on anchor graph while modal correlation can be approximated by Hamming distance. Especially, extracted features from the multi-modal data are classified using deep sparse autoencoders classifier. Finally, experiments conduct on the AD Neuroimaging Initiative database show that DS-FSH outperforms comparable methods of AD classification. To conclude, DS-FSH identifies multi-modal features closely associated with AD, which are expected to contribute significantly to understanding of the pathogenesis of AD.

RASP: Optimal Single Puncta Detection in Complex Cellular Backgrounds.

Super-resolution and single-molecule microscopies have been increasingly applied to complex biological systems. A major challenge of these approaches is that fluorescent puncta must be detected in the low signal, high noise, heterogeneous background environments of cells and tissue. We present RASP, Radiality Analysis of Single Puncta, a bioimaging-segmentation method that solves this problem. RASP removes false-positive puncta that other analysis methods detect and detects features over a broad range of spatial scales: from single proteins to complex cell phenotypes. RASP outperforms the state-of-the-art methods in precision and speed using image gradients to separate Gaussian-shaped objects from the background. We demonstrate RASP's power by showing that it can extract spatial correlations between microglia, neurons, and α-synuclein oligomers in the human brain. This sensitive, computationally efficient approach enables fluorescent puncta and cellular features to be distinguished in cellular and tissue environments, with sensitivity down to the level of the single protein. Python and MATLAB codes, enabling users to perform this RASP analysis on their own data, are provided as Supporting Information and links to third-party repositories.