Clinical outcomes of KRAS-mutant non-small cell lung cancer under untargeted therapeutic regimes in the real world: a retrospective observational study.

Background: Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation seemingly suffered less effective therapeutic regimens in the absence of widely-accepted targeted drugs compared with other mutation types in non-small cell lung cancer (NSCLC). However, whether these non-selective therapy schedules for KRAS mutation matters is still under debate. Correspondingly, we aimed to compare the long term expectancy of indicated therapeutic regimes and further explore the optimal schemes of KRAS mutated NSCLC in the absence of targeted drugs in this retrospective study cohort. Methods: We conducted a single-center retrospective analysis among 66 patients diagnosed with KRAS-mutant advanced NSCLC from November 2018 to December 2020. These enrolled cases were divided into different subgroups in light of mutant isotypes, pathological characteristics, and therapeutic regimes to uncover indicated long-term survival benefits. Additionally, clinical outcomes of treatment schedules and interventional lines to KRAS-mutant NSCLC were described in detail. Results: This cohort enrolled 8 patients with stage IIIB (12.1%) and 58 patients with stage IV (87.9%) with the median age 62 years, ranging from 32 to 91 years old. Genetically, G12C conducted as the most common KRAS mutation type, accounting for 30.3%. Pemetrexed combined with platinum chemotherapy seemed to be a priority (72.7%), and chemotherapy combined with immunotherapy became an alternative (15.2%) in clinic. Performing further analysis of long-term survival of patients receiving different treatment methods indicated that the median overall survival (mOS) in first-line therapy with antiangiogenesis or untreated was 13 and 12 months, respectively (P=0.79). In the first-line regimen, median survival was 17 months for patients who received combined immune checkpoint inhibitors and 12 months for those who did not (P=0.34). The mOS was 20 months for those who had used immune checkpoint inhibitors and 12 months for those who had not (P=0.11). Survival analysis results of NSCLC patients with different KRAS mutation types showed the median survival time of patients with G12C mutation type and patients without with nonG12C mutation type was 19 and 12 months, respectively (P=0.37). Conclusions: In the absence of KRAS targeted drugs, available treatment plans failed to benefit KRAS mutant sufferers regardless of isotypes, making the KRAS-targeted drugs urgent.

[Long-term Succession Patterns and Driving Factors of Water Quality in a Flood-pulse System Lake: A Case Study of Lake Luoma, Jiangsu Province].

Lake Luoma is an important storage lake for the Eastern route of the South-to-North Water Diversion Project (NSBD), which has many functions including flood control and irrigation, drinking water supply, and ecological maintenance. In order to understand the succession patterns and driving factors of water quality in Lake Luoma, we used monthly monitoring data from 2009 to 2020 in combination with historical data from 1996 to 2008. The long-term succession patterns, seasonal dynamics, and spatial patterns of total nitrogen (TN), total phosphorus (TP), permanganate index, and ammonia nitrogen (NH+4-N) were examined, and the influence of meteorological and hydrological factors on water quality was explored through correlation analyses and generalized additive models. The results showed that it remained in the status of grade Ⅳ-inferior Ⅴ over the past 25 years. The concentration of TN, which was the main pollutant, changed significantly (1.06-3.49 mg·L-1), experiencing three stages of gradual decline (1996-2002), significant interannual fluctuation (2002-2015), and significant increase (2015-2020). Permanganate index decreased significantly (2.97-6.38 mg·L-1), whereas TP and NH+4-N concentration fluctuated slightly, ranging from 0.024-0.076 mg·L-1 and 0.11-0.69 mg·L-1, respectively. The concentration of TN and TP increased abnormally in the summer of 2017-2020, reaching 3.30 mg·L-1 and 0.14 mg·L-1 in August, respectively, which was approximately 1.5 and 2.4 times the annual average. In terms of seasonal dynamics, the seasonal variation in water quality between summer/autumn and winter/spring reversed after 2015, with water quality in summer/autumn being worse than that in winter and spring, indicating the exacerbation of eutrophication. The water quality in the southern area was obviously better than that in the northern area. The input of pollutants from the Yihe River and Middle Canal increased with water quantity since 2015, which drove the water quality deterioration through nutrients. Our results suggested that the water quality of Lake Luoma should be improved by strengthening exogenous pollution reduction, endogenous control, polder dismantling, and ecological restoration.

Antibacterial efficacy evaluation and mechanism probe of small lysine chalcone peptide mimics.

Bacterial resistance is a growing threat to public health and a significant barrier to anti-infective treatment. Consequently, the development of novel antibacterial strategies to address this issue is critical. Herein, we developed a series of chalcone-alkyl-lysine compounds by mimicking the chemical structure and antibacterial properties of cationic antimicrobial peptides. Most of the compounds showed significant antibacterial activity against Gram-positive and Gram-negative bacteria. Compound 6d displayed potent antibacterial activity against Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), with MICs of 1-4 µg/mL. In addition, 6d exhibited excellent antibacterial activity against clinical MRSA and NDM-positive isolates, bactericidal properties, low resistance frequency. The mechanism studies revealed that compound 6d destroys bacterial cell membranes by interacting with phosphatidylglycerol (PG), causing the production of reactive oxygen species (ROS) and the leakage of nucleic acids, resulting in bacterial death. Furthermore, compound 6d did not exhibit any observable toxicity in HeLa and HEK293 cells at 8 × MIC. As a result, the findings suggest that compound 6d has potential therapeutic effects against bacterial infections and could be a promising drug candidate for future research.

Activation of aminocyclopropanes via radical intermediates.

Aminocyclopropanes are versatile building blocks for accessing high value-added nitrogen-containing products. To control ring-opening promoted by ring strain, the Lewis acid activation of donor-acceptor substituted systems is now well established. Over the last decade, alternative approaches have emerged proceeding via the formation of radical intermediates, alleviating the need for double activation of the cyclopropanes. This tutorial review summarizes key concepts and recent progress in ring-opening transformations of aminocyclopropanes via radical intermediates, divided into formal cycloadditions and 1,3-difunctionalizations.

A real-world, population-based study of the trends for incidence and prognosis in high-grade neuroendocrine tumor of cervix.

To explore the incidence and prognosis trends for high-grade cervical neuroendocrine tumor (HGCNET) and construct a nomogram to predict prognosis for HGCNET. Annual age-adjusted incidence of HGCNET from 1975 to 2015 was retrieved from the Surveillance, Epidemiology, and End Results program, the linear regression, poisson regression and annual percentage changes were used to assess the incidence trend. Also, trends for relative survival (RS) and overall survival (OS) in HGCNET patients from 1975 to 2015 were evaluated. From 1988 to 1975, 514 HGCNET patients were selected and divided into two cohorts with a ratio of 7:3. Nomogram to predict OS for these patients was constructed and validated. The incidence trend for HGCNET was unchanged in the past four decades (P = 0.734), but the proportion of HGCNET in diagnosed cervical cancer slightly increased from 0.9% in 1975 to 1.9% in 2015 (P < 0.001). The 5-year RS and OS for HGCNET in the study periods decreased steadily (RS: P = 0.009; OS: P = 0.008). Nomogram incorporating age, T stage, lymph-node positive, distant metastasis and surgery was constructed. The C-index of the nomogram was 0.716 (0.680-0.752), which was higher than the FIGO staging system. The incidence of HGCNET remained unchanged in the past four decades but the proportion of HGCNET has slightly increased. Besides, a steadily decreasing survival for HGCNET was observed in the study periods. A nomogram was constructed to better predict prognosis for HGCNET.

Physiological and transcriptomic analyses reveal novel insights into the cultivar-specific response to alkaline stress in alfalfa (Medicago sativa L.).

Soil alkalization severely limits plant growth and development, however, the mechanisms of alkaline response in plants remain largely unknown. In this study, we performed physiological and transcriptomic analyses using two alfalfa cultivars (Medicago sativa L.) with different sensitivities to alkaline conditions. The chlorophyll content and shoot fresh mass drastically declined in the alkaline-sensitive cultivar Algonquin (AG) following alkaline treatment (0-25 mM Na2CO3 solution), while the alkaline-tolerant cultivar Gongnong NO.1 (GN) maintained relatively stable growth and chlorophyll content. Compared with AG, GN had higher contents of Ca2+ and Mg2+; the ratios of Ca2+ and Mg2+ to Na+, proline and soluble sugar, as well as higher enzyme activities of peroxidase (POD) and catalase (CAT) under the alkaline conditions. Furthermore, transcriptomic analysis identified three categories of alkaline-responsive differentially expressed genes (DEGs) between the two cultivars: 48 genes commonly induced in both the cultivars (CAR), 574 genes from the tolerant cultivar (TAR), and 493 genes from the sensitive cultivar (SAR). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that CAR genes were mostly involved in phenylpropanoid biosynthesis, lipid metabolism, and DNA replication and repair; TAR genes were significantly enriched in metabolic pathways, such as biosynthesis of amino acids and secondary metabolites including flavonoids, and the MAPK signaling pathway; SAR genes were specifically enriched in vitamin B6 metabolism. Taken together, the results identified candidate pathways associated with genetic variation in response to alkaline stress, providing novel insights into the mechanisms underlying alkaline tolerance in alfalfa.

Prevalence of celiac disease in China: Meta-analysis and serological survey in high-risk populations.

OBJECTIVE: To summarize data from a serological survey of high-risk populations in Guangdong Province, China, and to perform a meta-analysis to investigate the prevalence and seroprevalence of celiac disease (CD) in the Chinese general and high-risk populations. METHODS: We collected data from the serological survey of high-risk population of CD in Guangdong Province, China (N = 1390) by testing their serum tissue transglutaminase immunoglobulin A (tTG-IgA), deamidated gliadin peptides immunoglobulin A (DGP-IgA) and deamidated gliadin peptides immunoglobulin G (DGP-IgG). Additionally, a literature search was performed on PubMed, EMBASE, Cochrane Library and three Chinese databases for articles published up to 20 December 2020 to estimate the pooled prevalence and seroprevalence of CD in China. RESULTS: In the serological survey, 0.94% (13/1390) of individuals were positive for CD antibodies. In a meta-analysis of 18 studies, the seroprevalence of CD in the general Chinese population was 0.27% (95% confidence interval [CI] 0.02%-0.71%). While that in the high-risk population was 8.34% (95% CI 4.90%-12.54%) (odds ratio 7.27, 95% CI 4.06-13.04). The prevalence of biopsy-confirmed CD in high-risk Chinese populations was 4.44% (95% CI 1.53%-8.58%). The seroprevalence of CD varied with patients' geographical origin, being higher in northern China than in southern China. CONCLUSIONS: Early diagnosis of CD by serological screening in high-risk population and generous serological testing in those with vague symptoms, especially in northern China, are recommended.

Combined analysis of C-reactive protein in pleural fluid and serum is effective in the differential diagnosis of exudative pleural effusions.

BACKGROUND: Exudative pleural effusion (EPE) is one of the common pleural manifestations of various diseases. Differential diagnosis of EPE is imperative clinically as it identifies different causes of EPE, thereby, enabling effective treatments. Thoracoscopy is a useful tool for differential diagnosis of EPE; however, some patients refuse thoracoscopic examination due to its invasive nature. In addition, the specificity and sensitivity of existing routine tests of EPE are unsatisfactory. Therefore, there is a great need to establish an effective method for the differential diagnosis of EPE. METHODS: This study was a single-institution retrospective analysis of diagnostic efficiency of C-reactive protein (CRP) and procalcitonin (PCT) between March 2018 and September 2018. A total of 87 patients diagnosed with EPE were enrolled. All participants underwent diagnostic thoracentesis. The EPE was examined using biochemical, routine, microbiological, and cytological methods. Pathological cytology detection was necessary for those suspected of malignant PE. Benign PE originates in patients with pneumonia, empyema, and tuberculosis. The levels of CRP and PCT in EPE and serum were measured before treatment. Correlation analysis and receiver-operating characteristic (ROC) curve analysis were conducted to determine the underlying relationship between levels of CRP and PCT, and for differential diagnosis. RESULTS: The ROC analysis showed that the sensitivity and specificity for the analysis of pleural fluid CRP (p-CRP) were higher (cut-off: 17.55 pg/mL; sensitivity: 75.00%, specificity: 83.90%) than that of serum CRP (s-CRP, cut-off: 23.90 pg/mL; sensitivity: 71.00%, specificity: 80.4%) in the differential diagnosis for EPE. However, the analysis of pleural fluid PCT (p-PCT) and serum PCT (s-PCT) did not demonstrate correlations with EPE. Combined analysis of p-CRP (cut-off: 17.55 mg/dL) with s-CRP (cut-off: 23.9 pg/mL) showed the highest diagnostic accuracy (88.4%) in diagnosing infectious EPE. CONCLUSIONS: The data support the close relationship between combined analysis of p-CRP with s-CRP and effective and accurate differential diagnosis of EPE, due to its higher sensitivity and specificity. However, as a highly sensitive marker for diagnosing bacterial infections, neither s-PCT nor p-PCT, showed correlations with the differential diagnosis of EPE.

Diamine Synthesis via the Nitrogen-Directed Azidation of σ- and π-C-C Bonds.

Diamines are essential building blocks for the synthesis of agrochemicals, drugs, and organic materials, yet their synthesis remains challenging, as both nitrogens need to be differentiated and diverse substitution patterns (1,2, 1,3, or 1,4) are required. We report herein a new strategy giving access to 1,2, 1,3, and 1,4 amido azides as orthogonally protected diamines based on the nitrogen-directed diazidation of alkenes, cyclopropanes, and cyclobutanes. Commercially available copper thiophene-2-carboxylate (CuTc, 2 mol %) as catalyst promoted the diazidation of both π and σ C-C bonds within 10 min in the presence of readily available oxidants and trimethylsilyl azide. Selective substitution of the formed α-amino azide by carbon nucleophiles (electron-rich aromatic, malonate, organosilicon, organoboron, organozinc, and organomagnesium compounds) was then achieved in a one-pot fashion, leading to the formation of 1,2-, 1,3-, and 1,4-diamines with the amino groups protected orthogonally as an amide/carbamate and an azide.

Comparison of Different Lymph Node Staging Schemes for Predicting Survival Outcomes in Node-Positive Endometrioid Endometrial Cancer Patients.

Objective: To compare the prognostic predictive performance of six lymph node (LN) staging schemes: American Joint Committee on Cancer (AJCC) N stage, number of retrieved lymph nodes (NRLN), number of positive lymph nodes (NPLN), number of negative lymph nodes (NNLN), lymph node ratio (LNR), and log odds of positive lymph nodes (LODDS) among node-positive endometrioid endometrial cancer (EEC) patients. Methods: A total of 3,533 patients diagnosed with node-positive EEC between 2010 and 2016 from the Surveillance, Epidemiology, and End Results (SEER) database were retrospectively analyzed. We applied X-tile software to identify the optimal cutoff value for different staging schemes. Univariate and multivariate Cox regression models were used to assess the relationships between different LN schemes and survival outcomes [disease-specific survival (DSS) and overall survival (OS)]. Moreover, Akaike information criterion (AIC) and Harrell concordance index (C-index) were used to evaluate the predictive performance of each scheme in both continuous and categorical patterns. Results: N stage (N1/N2) was not an independent prognostic factor for node-positive EEC patients based on multivariate analysis (DSS: p = 0.235; OS: p = 0.145). Multivariate model incorporating LNR demonstrated the most superior goodness of fit regardless of continuous or categorical pattern. Regarding discrimination power of the models, LNR outperformed other models in categorical pattern (OS: C-index = 0.735; DSS: C-index = 0.737); however, LODDS obtained the highest C-index in continuous pattern (OS: 0.736; DSS: 0.739). Conclusions: N stage (N1/N2) was unable to differentiate the prognosis for node-positive EEC patients in our study. However, LNR and LODDS schemes seemed to have a better predictive performance for these patients than other number-based LN schemes whether in DSS or OS, which revealed that LNR and LODDS should be more helpful in prognosis assessment for node-positive EEC patients than AJCC N stage.

Conditional survival for high-risk early-stage cervical cancer patients with lymph node metastasis after hysterectomy.

BACKGROUND: To estimate conditional survival (CS) for high-risk early-stage cervical cancer patients with lymph node metastasis after hysterectomy. METHODS: 1964 T1-2N1M0 cervical cancer patients who underwent primary hysterectomy from 2004 to 2015 were extracted from the Surveillance, Epidemiology, and End Result (SEER) Program. Univariate and multivariate cox regression analysis were used to identify independent risk factors. 5-year conditional disease-specific survival (CDS5) and 5-year conditional relative survival (CRS5) were estimated. CDS5 and CRS5 stratified by risk factors were further calculated. RESULTS: CDS5 and CRS5 increased from 71.0% and 73.7% at 0-year to 89.2% and 91.7% at 5-year, respectively. Inversely, the actuarial disease-specific survival and RS dropped from 71.0% and 73.7% at 5-year to 63.3% and 67.6% at 10-year, respectively. Patients with unfavorable factors had a bigger gap between actuarial survival and CS. Both CDS5 and CRS5 curves across stratas of each prognostic factor had a tendency to level off with time elapsing. Notably, CRS5 couldn't exceed 95% even after 5-year follow-up except for patients with grade I disease (CRS5 at 5-year: 100%) or tumor size less than 2 cm (CRS5 at 5-year: 96%). CONCLUSION: CS increased over time while actuarial survival decreased as time passed. Patients with unfavorable factors had bigger improvement in CS than those with favorable factors. Excess mortality still existed in these patients after 5-year follow-up compared to the general population except for patients with grade I disease or tumor size <2 cm, who might gradually decrease follow-up times after 5-year.

Panax Notoginseng Saponin Attenuates Gastric Mucosal Epithelial Cell Injury Induced by Dual Antiplatelet Drugs through COX and PI3K/Akt/ VEGF-GSK-3ß-RhoA Network Pathway.

OBJECTIVE: To elucidate the underlying mechanism of Panax notoginseng saponin (PNS) on gastric epithelial cell injury and barrier dysfunction induced by dual antiplatelet (DA). METHODS: Human gastric mucosal epithelial cell (GES-1) was cultured and divided into 4 groups: a control, a DA, a PNS+DA and a LY294002+PNS+DA group. GES-1 apoptosis was detected by flow cytometry, cell permeability were detected using Transwell, level of prostaglandins E2 (PGE2), 6-keto-prostaglandin F1α (6-keto-PGF1α) and vascular endothelial growth factor (VEGF) in supernatant were measured by enzyme linked immunosorbent assay (ELISA), expression of phosphatidylinositide 3-kinase (PI3K), phosphorylated-PI3K (p-PI3K), Akt, phosphorylated-Akt (p-Akt), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), glycogen synthase kinase-3ß (GSK-3ß) and Ras homolog gene family member A (RhoA) were measured by Western-blot. RESULTS: DA induced apoptosis and hyper-permeability in GES-1, reduced supernatant level of PGE2, 6-keto-PGF1α and VEGF (P<0.05). Addition of PNS reduced the apoptosis of GES-1 caused by DA, restored the concentration of PGE2, 6-keto-PGF1α and VEGF (P<0.05). In addition, PNS attenuated the alteration of COX-1 and COX-2 expression induced by DA, up-regulated p-PI3K/p-Akt, down-regulated RhoA and GSK-3ß. LY294002 mitigated the effects of PNS on cell apoptosis, cell permeability, VEGF concentration, and expression of RhoA and GSK-3ß significantly. CONCLUSIONS: PNS attenuates the suppression on COX/PG pathway from DA, alleviates DA-induced GES-1 apoptosis and barrier dysfunction through PI3K/Akt/ VEGF-GSK-3ß-RhoA network pathway.

Fine-scale genetic structure of the overwintering Chilo suppressalis in the typical bivoltine areas of northern China.

The rice stem borer (RSB), Chilo suppressalis (Lepidoptera: Pyralidae), is an important agricultural pest that has caused serious economic losses in the major rice-producing areas of China. To effectively control this pest, we investigated the genetic diversity, genetic differentiation and genetic structure of 16 overwintering populations in the typical bivoltine areas of northern China based on 12 nuclear microsatellite loci. Moderate levels of genetic diversity and genetic differentiation among the studied populations were detected. Neighbour-joining dendrograms, Bayesian clustering and principal coordinate analysis (PCoA) consistently divided these populations into three genetic clades: western, eastern and northern/central. Isolation by distance (IBD) and spatial autocorrelation analyses demonstrated no correlation between genetic distance and geographic distance. Bottleneck analysis illustrated that RSB populations had not undergone severe bottleneck effects in these regions. Accordingly, our results provide new insights into the genetic relationships of overwintering RSB populations and thus contribute to developing effective management strategies for this pest.

Synthesis of Thiochromans via [3+3] Annulation of Aminocyclopropanes with Thiophenols.

We report the one-pot synthesis of 4-amino thiochromans using simple aminocyclopropanes and thiophenols through a formal [3+3] annulation reaction. This reaction proceeds under mild conditions with good functional group tolerance. The thiochroman core was formed with complete regioselectivity, and modification of complex drug molecules containing an aminocyclopropane was also realized.

Mitochondrial DNA diversity and population structure of Laodelphax striatellus across a broad geographic area in China.

The small brown planthopper (SBPH), Laodelphax striatellus Fallén (Hemiptera: Delphacidae), is a crucial devastating rice pest in East Asia. To effectively control this pest, we investigate the genetic diversity, genetic differentiation and genetic structure of 49 populations in China based on a 596 bp fragment of the mitochondrial DNA cytochrome c oxidase subunit I (mtDNA COI) gene. Overall, 83 haplotypes were detected in 1253 mtDNA COI sequences. High levels of genetic variability (Hd = 0.756 ± 0.009, π = 0.00416 ± 0.00011) and genetic differentiation (FST = 0.262, p < .001) were observed. Bayesian inference phylogenetic and median-joining haplotype network analyses indicated no obvious geographical distribution pattern among haplotypes. Hierarchical AMOVA and SAMOVA revealed no genetically distinct groups and lack of obvious phylogeographic structure. Isolation by distance (IBD) analysis results demonstrated no correlation between genetic differentiation and geographic distance. Finally, the demographic history of SBPH examined by neutrality tests and mismatch distribution analyses illustrated a sudden population expansion at the large spatial scale in China.

Tubeimoside­1 induces apoptosis in human glioma U251 cells by suppressing PI3K/Akt­mediated signaling pathways.

Tubeimoside-1 (TBMS1), a traditional Chinese herb extracted from Bolbostemma paniculatum (Maxim.), induces apoptosis in a number of human cancer cell lines. TBMS1 has been reported to induce apoptosis in human glioma cells, however the mechanism remains to be elucidated. The present study explored TBMS1­induced PI3K/Akt­related pathways in human glioma cells. The human glioma U251 and the human astrocyte (HA) cell lines were treated with various concentrations of TBMS1. MTT assays were conducted to analyze cell viability. Cell cycle distribution and the rate of apoptosis were assessed using flow cytometry. BrdU incorporation and Hoechst 33342 staining were performed to analyze the cell cycle and apoptosis, respectively. Western blotting was performed to investigate protein expression levels. The results demonstrated that TBMS1 reduced cell viability in human glioma cells U251 by suppressing Akt phosphorylation. Subsequently, TBMS1 inhibited DNA synthesis and induced G2/M phase arrest by targeting the PI3K/Akt/p21 and the cyclin­dependent kinase 1/cyclin B1 signaling cascades. In addition, TBMS1 triggered apoptosis via the PI3K/Akt­mediated Bcl­2 signaling pathway. These results demonstrated that TBMS1 prevented the progression of gliomas via the PI3K/Akt­dependent pathway, which provided a theoretical basis for in vivo studies to use TBMS1 as potential therapy for the prevention of cancer.

Genetic variation and phylogeographic structure of Spodoptera exigua in western China based on mitochondrial DNA and microsatellite markers.

The beet armyworm, Spodoptera exigua, is a significant agricultural pest of numerous crops and has caused serious economic losses in China. To effectively control this pest, we analyzed its genetic variation, population genetic structure and demographic history. We used mitochondrial DNA (mtDNA) fragments of the cytochrome oxidase subunit I (COI) and eight nuclear microsatellite loci to investigate genetic diversity and population genetic structure of S. exigua populations at 14 sampling sites in western China. Both mtDNA and microsatellite data indicated low levels of genetic diversity among all populations. A moderate genetic differentiation among some S. exigua populations was detected. Neighbor-joining dendrograms, STRUCTURE, and principal coordinate analysis (PCoA) revealed two genetically distinct groups: the KEL group and the remaining population group. Isolation by distance (IBD) results showed a weak significant correlation between geographic distance and genetic differentiation. Haplotype networks, neutrality testing, and mismatch distribution analysis indicated that the beet armyworm experienced a recent rapid expansion without a recent genetic bottleneck in western China. Thus, the results of this population genetic study can help with the development of strategies for managing this highly migratory pest.

Oxidative Fluorination of Cyclopropylamides through Organic Photoredox Catalysis.

We report an oxidative ring-opening strategy to transform cyclopropylamides and cyclobutylamides into fluorinated imines. The imines can be isolated in their more stable hemiaminal form, with the fluorine atom installed selectively at the γ or δ position. Both inexpensive benzophenone with UVA light or organic and inorganic dyes with blue light could be used as photoredox catalysts to promote this process. Various fluorinated amines were then obtained by nucleophilic attack on the hemiaminals in one pot, giving access to a broad range of useful building blocks for medicinal chemistry.

Responses of annual herb plant community characteristics to increased precipitation and reduced wind velocity in semiarid sandy grassland.

Changes in precipitation regimes and wind velocity tend to alter structure and composition of the annual herb plant community, with consequent effects on ecological functioning and biodiversity maintenance. We examined the effects of increased precipitation and reduced wind velocity on annual herb plant community characteristics via a manipulative experiment from the middle of April to middle of August, 2016. There was significant increment in species richness with increased precipitation from June to August, and there were interactive effects between increased precipitation and reduced wind velocity especially in June and the end of July. From June to August, increased precipitation, reduced wind velocity as well as their interaction stimulated sandy plant community development. There was considerable elevation in plant coverage with increased precipitation, and also there was an interactive effect of increased precipitation with 20% reduced wind velocity. However, reduced wind velocity caused more significant stimulation (p < .01) in plant height. Moreover, dominant plants, Salsola collina, Bassia dasyphylla, and Setaria viridis, contributed equally to the elevated community coverage with increased precipitation, whereas S. collina occupied a much larger proportion on the augment of community height compared with the other two species under the increased precipitation and reduced wind velocity. Elevated Shannon-Wiener index was detected with increased precipitation in June and July. Furthermore, increased precipitation and reduced wind velocity enhanced aboveground and belowground biomass, respectively. These species traits-in structuring and composing plant community were suggested to be conducive to deep understanding the plant functioning and dynamics under global changing precipitation regimes and atmospheric wind velocity scenarios.