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The mechanism by which DNMT3B facilitates esophageal cancer (ESCA) progression is currently unknown, despite its association with adverse prognoses in several cancer types. To investigate the potential therapeutic effects of the Chinese herbal medicine rhubarb on esophageal cancer (ESCA), we adopted an integrated bioinformatics approach. Gene Set Enrichment Analysis (GSEA) was first utilized to screen active anti-ESCA components in rhubarb. We then employed Weighted Gene Co-expression Network Analysis (WGCNA) to identify key molecular modules and targets related to the active components and ESCA pathogenesis. This system-level strategy integrating multi-omics data provides a powerful means to unravel the molecular mechanisms underlying the anticancer activities of natural products, like rhubarb. To investigate module gene functional enrichment, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted. In addition, we evaluated the predictive impact of DNMT3B expression on ESCA patients utilizing the Kaplan–Meier method. Finally, we conducted experiments on cell proliferation and the cell cycle to explore the biological roles of DNMT3B. In this study, we identified Rhein as the main active ingredient of rhubarb that exhibited significant anti-ESCA activity. Rhein markedly suppressed ESCA cell proliferation. Utilizing Weighted Gene Co-expression Network Analysis (WGCNA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, we determined that the blue module was associated with Rhein target genes and the cell cycle. Additionally, DNMT3B was identified as a Rhein target gene. Analysis of The Cancer Genome Atlas (TCGA) database revealed that higher DNMT3B levels were associated with poor prognosis in ESCA patients. Furthermore, Rhein partially reversed the overexpression of DNMT3B to inhibit ESCA cell proliferation. In vitro studies demonstrated that Rhein and DNMT3B inhibition disrupted the S phase of the cell cycle and affected the production of cell cycle-related proteins. In this study, we found that Rhein exerts its anti-proliferative effects in ESCA cells by targeting DNMT3B and regulating the cell cycle. [ABSTRACT FROM AUTHOR]

Due to their distinctive morphology, significant surface-to-volume ratio, and metal-like electrical conductivity, MXenes have emerged as highly promising gas-sensing materials. Traditional MXene-based gas sensors predominantly rely on the electrical conductivity of MXenes for signal transduction. However, it is crucial to explore alternative signal transduction mechanisms to fully unlock the potential of MXenes in gas sensing applications. In this study, we have successfully showcased the development of a mass-transduction-based MXene gas sensor, utilizing MXenes as the adaptable receptor and MQTF as the transducer. The interaction between the gas analyte and MXenes induces a change in mass, resulting in a resonant frequency shift of the MQTF. This signal transduction mechanism eliminates the dependency on the electrical conductivity of MXenes, offering a broader range of possibilities for chemical modification of MXenes without concerns about compromising their conductivity. By engineering Ti3C2Tx surfaces, we have demonstrated high sensitivity and selectivity tuning of MXene-MQTF gas sensors for detecting CO, SO2, and NH3. This antisymmetric mass-transduction-based (low-cost, stable, sensitive, and practical tuning fork-based) MXene gas sensor demonstrated exceptional sensing performance, customizable selectivity, and high cost-effectiveness. This study paves the way for designing high-performance MXene-based chemical sensors and expands the scope of potential applications in air quality monitoring, wearable devices, the Internet of Things (IoT), and robotics. [ABSTRACT FROM AUTHOR]

Although extensive research has examined the credit risk of real estate enterprises, the relationship between the political connection of real estate enterprises and these enterprises' credit risk has not been formally studied. Using the panel data of 123 real estate listed companies in the Chinese stock market from 2008 to 2021, this paper finds a significant positive correlation between the political connection of private real estate listed companies and their credit risk. This phenomenon is attributed to the excessive debt that benefits from political connections since it may raise the credit risk of any real estate firm. Interestingly, considering that 2013 is the first year of China's Internet finance era, we find that the popularity of Internet finance and other decentralized lending financing channels may enhance the impact of political connections on real estate credit risk. Our findings provide new micro evidence for the influencing factors and mechanism of credit risk of real estate enterprises during the recent "credit crisis" in the real estate market in China. [ABSTRACT FROM AUTHOR]

Nano silver (Ag) was metallic Ag monomers with particle size to the nanoscale. Photocatalyst was a kind of semiconductor material with photocatalytic function. Loading precious metal Ag onto semiconductor surfaces by microwave, laser-induced, solvent-thermal and hydrothermal methods could capture photogenerated electrons, reduced the compounding rate of holes and photogenerated electrons during the photocatalytic process, thereby improving the electron transfer efficiency of photocatalysis and enhancing the absorption of visible light by silver nanoparticles through the plasma resonance effect. The highly reactive free radicals produced by photocatalysts were used in the organic degradation process to degrade organic matter into inorganic matter and was a faster, more efficient and less polluting method of pollutant degradation, which has attracted a lot of attention from researchers. This review discussed the modification of various types of photocatalysts by nano Ag through different methods. The photocatalytic degradation of dyes, antibiotics and persistent organic pollutants by different modified composites was also analyzed. This review covered the several ways and means in which nano Ag has modified diverse photocatalytic materials as well as the photocatalytic degradation of dyes, antibiotics and persistent organic pollutants. This review identified the drawbacks of the existing nano Ag-modified photocatalytic materials, including their low yield and lack of recyclability, and it also offered suggestions for potential future directions for their improvement. The purpose of this review was to further research on the technology of nano Ag-modified photocatalytic materials and to encourage the creation of new modified photocatalytic nanomaterials for the treatment of organic pollutant degradation. [ABSTRACT FROM AUTHOR]

Trace-amine-associated receptors (TAARs), a group of biogenic amine receptors, have essential roles in neurological and metabolic homeostasis1. They recognize diverse endogenous trace amines and subsequently activate a range of G-protein-subtype signalling pathways2,3. Notably, TAAR1 has emerged as a promising therapeutic target for treating psychiatric disorders4,5. However, the molecular mechanisms underlying its ability to recognize different ligands remain largely unclear. Here we present nine cryo-electron microscopy structures, with eight showing human and mouse TAAR1 in a complex with an array of ligands, including the endogenous 3-iodothyronamine, two antipsychotic agents, the psychoactive drug amphetamine and two identified catecholamine agonists, and one showing 5-HT1AR in a complex with an antipsychotic agent. These structures reveal a rigid consensus binding motif in TAAR1 that binds to endogenous trace amine stimuli and two extended binding pockets that accommodate diverse chemotypes. Combined with mutational analysis, functional assays and molecular dynamic simulations, we elucidate the structural basis of drug polypharmacology and identify the species-specific differences between human and mouse TAAR1. Our study provides insights into the mechanism of ligand recognition and G-protein selectivity by TAAR1, which may help in the discovery of ligands or therapeutic strategies for neurological and metabolic disorders.TAAR1 has a rigid consensus binding motif that binds to endogenous trace amine stimuli as well as two extended binding pockets that accommodate diverse chemotypes. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is the most common primary malignancy. Recently, antineoplastic attributes of homoharringtonine (HHT) have attracted lots of attention. This study investigated the molecular target and underlying mechanism of HHT in the CRC process by using a cellular and animal models. Methods: This study first detected the effects of HHT on the proliferation, cell cycle and apoptosis ability of CRC cells using CCK-8, Edu staining, flow cytometry and Western blotting assay. In vitro recovery experiment and in vivo tumorigenesis experiment were used to detect the targeted interaction between HHT and NKD1. After that, the downstream target and mechanism of action of HHT targeting NKD1 was determined using quantitative proteomics combined with co-immunoprecipitation/immunofluorescence assay. Results: HHT suppressed CRC cells proliferation by inducing cell cycle arrest and apoptosis in vitro and vivo. HHT inhibited NKD1 expression in a concentration and time dependent manner. NKD1 was overexpressed in CRC and its depletion enhanced the therapeutic sensitivity of HHT on CRC, which indicating that NKD1 plays an important role in the development of CRC as the drug delivery target of HHT. Furthermore, proteomic analysis revealed that PCM1 participated the process of NKD1-regulated cell proliferation and cell cycle. NKD1 interacted with PCM1 and promoted PCM1 degradation through the ubiquitin-proteasome pathway. The overexpression of PCM1 effectively reversed the inhibition of siNKD1 on cell cycle. Conclusions: The present findings revealed that HHT blocked NKD1 expression to participate in inhibiting cell proliferation and inducing cell apoptosis, ultimately leading to obstruction of CRC development through NKD1/PCM1 dependent mechanism. Our research provide evidence for clinical application of NKD1-targeted therapy in improving HHT sensitivity for CRC treatment. [ABSTRACT FROM AUTHOR]

Background: Liquid biopsies have become an integral part of cancer management as minimally invasive options to detect molecular and genetic changes. However, current options show poor sensitivity in peritoneal carcinomatosis (PC). Novel exosome-based liquid biopsies may provide critical information on these challenging tumors. In this initial feasibility analysis, we identified an exosome gene signature of 445 genes (ExoSig445) from colon cancer patients, including those with PC, that is distinct from healthy controls. Methods: Plasma exosomes from 42 patients with metastatic and non-metastatic colon cancer and 10 healthy controls were isolated and verified. RNAseq analysis of exosomal RNA was performed and differentially expressed genes (DEGs) were identified by the DESeq2 algorithm. The ability of RNA transcripts to discriminate control and cancer cases was assessed by principal component analysis (PCA) and Bayesian compound covariate predictor classification. An exosomal gene signature was compared with tumor expression profiles of The Cancer Genome Atlas. Results: Unsupervised PCA using exosomal genes with greatest expression variance showed stark separation between controls and patient samples. Using separate training and test sets, gene classifiers were constructed capable of discriminating control and patient samples with 100% accuracy. Using a stringent statistical threshold, 445 DEGs fully delineated control from cancer samples. Furthermore, 58 of these exosomal DEGs were found to be overexpressed in colon tumors. Conclusions: Plasma exosomal RNAs can robustly discriminate colon cancer patients, including patients with PC, from healthy controls. ExoSig445 can potentially be developed as a highly sensitive liquid biopsy test in colon cancer. [ABSTRACT FROM AUTHOR]

Albeit its importance, a large number of port authorities do not provide continuous or publicly available air emissions inventories (EIs) and thereby obscure the emissions contribution of ports. This is caused by, e.g., the economic effort generated by obtaining data. Therefore, the performance of abatement measures is not monitored and projected, which is specifically disadvantageous concerning top contributors such as container ships. To mitigate this issue, in this paper we propose port vessel EI prediction models by exploring the combination of different machine-learning algorithms, data from the one-off application of an activity-based bottom-up methodology and vessel-characteristics data. The results for this specific case show that prediction models enable acceptable trade-offs between the prediction performance and data requirements, promoting the creation of EIs. [ABSTRACT FROM AUTHOR]

Somatostatin receptor 2 (SSTR2) is highly expressed in neuroendocrine tumors and represents as a therapeutic target. Several peptide analogs mimicking the endogenous ligand somatostatin are available for clinical use, but poor therapeutic effects occur in a subset of patients, which may be correlated with subtype selectivity or cell surface expression. Here, we clarify the signal bias profiles of the first-generation peptide drug octreotide and a new-generation small molecule paltusotine by evaluating their pharmacological characteristics. We then perform cryo-electron microscopy analysis of SSTR2-Gi complexes to determine how the drugs activate SSTR2 in a selective manner. In this work, we decipher the mechanism of ligand recognition, subtype selectivity and signal bias property of SSTR2 sensing octreotide and paltusotine, which may aid in designing therapeutic drugs with specific pharmacological profiles against neuroendocrine tumors. Somatostatin receptor 2 (SSTR2) represents a therapeutic target of neuroendocrine tumors. Here, authors report two structures of SSTR2 bound to peptide octreotide and small molecule paltusotine, revealing the basis subtype selectivity and signal bias properties. [ABSTRACT FROM AUTHOR]

Introduction: Tumor agnostic circulating tumor DNA (ctDNA) is routinely used to guide treatment decisions in gastrointestinal (GI) cancers, especially metastatic cancers. The amount of ctDNA detected in plasma is affected by stage, tumor burden, and tumor vascularization. We hypothesized that peritoneal carcinomatosis (PC) is associated with lower ctDNA levels than other metastatic sites in GI cancers due to the plasma–peritoneal barrier. Methods: We conducted a retrospective analysis of patients with stage II–IV GI cancers treated at our institution between 2015 and 2020 with available panel-based ctDNA results (Guardant 360TM). ctDNA analysis was performed on early and pretreatment samples. We compared the reported maximum variant allele frequency (mVAF) of somatic mutations across metastatic sites. Results: Of the 279 patients with GI cancers (colorectal, upper GI, pancreaticobiliary), 212 had stage IV disease (PC: n = 61; visceral metastases: n = 138; other metastases: n = 13). Mean mVAF increased with increasing stages of disease (stage II: 3.6 ± 7; stage III: 6.4 ± 10; stage IV: 28.0 ± 51; p < 0.01). Among patients with stage IV disease, PC was associated with lower ctDNA levels independent of primary tumor site (PC only: 12.1%; PC+ visceral metastases: 26.8%; and visceral metastases only: 35.0%; p < 0.01). In a subset of patients (n = 27, matched pair analysis of genomic alterations (GAs) showed fewer GAs were detected in plasma compared with tissue. Conclusions: PC of GI origin is associated with significantly lower ctDNA levels compared with visceral metastasis. Caution is warranted when interpreting ctDNA results from patients with PC due to lower sensitivity for detecting actionable mutations. [ABSTRACT FROM AUTHOR]

Recently, enterprises and industries associated with intense pollution have been relocated in China, leaving behind abandoned polluted sites. Consequently, stabilization has attracted unprecedented attention and rapid development. However, too much focus has been placed on practicality and short-term effectiveness, whereas long-term effectiveness and sustainability concerns have been overlooked. The present study reports the findings of a national survey administered to stakeholders involved in soil stabilization projects over a decade to determine the pollution characteristics of industrial sites and current utilization status of stabilization technologies in China. One-hundred and fifty soil stabilization projects surveyed revealed that among 29% of chemical industry remained sites, 96.7% of the sites were heavily polluted with heavy metals and metalloids, mainly in the forms of lead, arsenic, and chromium. Our analyses of soil reuse methods revealed that landfilling was the primary strategy of soil disposal following stabilization and remediation. In addition, the reuse of treated soils is preferred to landfill waste treatment. Therefore, from the perspective of economy and reducing landfill loads, environmental management measures should be adopted based on the development objectives of different regions to avoid the failure of stabilization treatments and reapplication and over-repair problems, with the aim of establishing an evaluation method of "site-specific, analysis-specific" evaluation method. [ABSTRACT FROM AUTHOR]

Insufficient tumor accumulation and distribution of photosensitizers as well as low antitumor immunity severely restrict the therapeutic efficacy of photothermal therapy (PTT). Cancer-associated fibroblasts (CAFs) play a key role in tumor extracellular matrix (ECM) remodeling and immune evasion. Reshaping tumor microenvironment via CAF regulation might provide a potential approach for complete tumor elimination in combination with PTT. Here, tumor cell-derived microparticles co-delivering calcipotriol and Indocyanine green (Cal/ICG@MPs) are developed to modulate CAFs for improved PTT efficacy. Cal/ICG@MPs efficiently target tumor tissues and regulate CAFs to reduce tumor ECM, resulting in enhanced tumor accumulation and penetration of ICG to generate strong PTT efficacy and activate CD8+ T cell-mediated antitumor immunity. In addition, Cal/ICG@MPs-triggered CAF regulation enhances tumor infiltration of CD8+ T cells and ameliorates CAF-induced antigen-mediated activation-induced cell death of tumor-specific CD8+ T cells in response to PTT, eliciting long-term antitumor immune memory to inhibit tumor recurrence and metastasis. Our results support Cal/ICG@MPs as a promising drug to improve PTT efficacy in cancer treatment. Photothermal therapy (PTT) has emerged as a promising approach for cancer treatment. Here, in preclinical cancer models, the authors show that PTT efficacy could be improved using tumor cell-derived microparticles that co-deliver the photosensitizer indocyanine green and a vitamin-D receptor ligand, calcipotriol, resulting in tumor extracellular matrix remodelling and ameliorated anti-tumor immune responses. [ABSTRACT FROM AUTHOR]

The Western Tibetan Vortex (WTV) is a large-scale circulation pattern identified from year-to-year circulation variability, which was used to understand the causal mechanisms for slowdown of the glacier melting over the western Tibetan Plateau (TP). A recent argument has suggested the WTV is the set of wind field anomalies resulting from variability in near-surface air temperatures over the western TP (above 1500 m), which, in turn, is likely driven by the surface net radiation. This study thereby evaluates the above putative thermal-direct mechanism. By conducting numerical sensitivity experiments using a global atmospheric circulation model, SAMIL, we find a WTV-like structure cannot be generated from a surface thermal forcing imposed on the western TP. A thermally-direct circulation generated by the surface or near surface heating is expect to cause upward motions and a baroclinic structure above it. In contrast, downward motions and a quasi-barotropic are observed in the vertical structure of the WTV. Besides, we find variability of the surface net radiation (sum of the surface shortwave and longwave net radiation) over the western TP can be traced back to the WTV variability based on ERA5 data. The anticyclonic (cyclonic) WTV reduces (increases) the cloudiness through the anomalous downward (upward) motions, causes more (less) input shortwave net radiation and thereby more (less) surface net radiations, resulting in the warmer (cooler) surface and near-surface air temperature over the western TP. The argument is constructive in encouraging examination of the radiative balance processes that complements previous studies. [ABSTRACT FROM AUTHOR]

Food effect (FE) and gastric pH-dependent drug-drug interactions (DDIs) are both absorption-related. Here, we evaluated if Biopharmaceutics Classification System (BCS) classes may be correlated with FE or pH-dependent DDIs. Trends in FE data were investigated for 170 drugs with clinical FE studies from the literature and new drugs approved from 2013 to 2019 by US Food and Drug Administration. A subset of 38 drugs was also evaluated to determine whether FE results can inform the need for a gastric pH-dependent DDI study. The results of FE studies were defined as no effect (AUC ratio 0.80–1.25), increased exposure (AUC ratio ≥1.25), or decreased exposure (AUC ratio ≤0.8). Drugs with significantly increased exposure FE (AUC ratio ≥2.0; N=14) were BCS Class 2 or 4, while drugs with significantly decreased exposure FE (AUC ratio ≤0.5; N=2) were BCS Class 1/3 or 3. The lack of FE was aligned with the lack of a pH-dependent DDI for all 7 BCS Class 1 or 3 drugs as expected. For the 13 BCS Class 2 or 4 weak base drugs with an increased exposure FE, 6 had a pH-dependent DDI (AUC ratio ≤0.8). Among the 16 BCS Class 2 or 4 weak base drugs with no FE, 6 had a pH-dependent DDI (AUC ratio ≤0.8). FE appears to have limited correlation with BCS classes except for BCS Class 1 drugs, confirming that multiple physiological mechanisms can impact FE. Lack of FE does not indicate absence of pH-dependent DDI for BCS Class 2 or 4 drugs. [ABSTRACT FROM AUTHOR]

Abnormal local spontaneous brain activity during the resting state has been observed in chronic obstructive pulmonary disease (COPD). However, it is still largely unclear whether the abnormalities are related to specific frequency bands. Our purpose was to explore intrinsic neural activity changes in different frequency bands by using the amplitude of low-frequency fluctuation (ALFF) method in stable COPD patients. Nineteen stable COPD patients and twenty gender-, age- and education-matched normal controls (NCs) underwent functional magnetic resonance imaging scans, cognitive function tests and lung function tests. Two different frequency bands (slow-4: 0.027–0.073 Hz; slow-5: 0.01–0.027 Hz) were calculated and analyzed for frequency-dependent intrinsic neural activity by using the ALFF method. A two-way analysis of variance test was used to compare the main effects of the groups and the frequency bands in the ALFF method. Further post-hoc t-tests were used to compare the differences between COPD patients and NCs in terms of the different frequency bands. A Pearson's correlation analysis was performed to explore the relationship between the altered ALFF brain areas in the different frequency bands and the clinical evaluations in the COPD patients. There were main effects of the groups including significantly higher ALFF values in the right superior temporal gyrus (STG), the bilateral cerebellum posterior lobe (CPL), the right lingual gyrus (LG) and the right brainstem, and as well as significantly decreased ALFF values in the right inferior parietal lobule (IPL) and the angular. The main effect of frequency was demonstrated in the CPL, the STG, the prefrontal cortex and the middle cingulate gyrus. Furthermore, COPD patients exhibited more widespread alterations in intrinsic brain activity in the slow-5 band than in the slow-4 band. Moreover, the abnormal intrinsic brain activity in the slow-4 and slow-5 bands were associated with PaCO2 in COPD patients. These current results indicated that COPD patients showed abnormal intrinsic brain activity in two different frequency bands, and abnormal intrinsic neuronal activity in different brain regions could be better detected by slow-5 band. These observations may provide a neoteric view into understanding the local neural psychopathology in stable COPD patients. [ABSTRACT FROM AUTHOR]

Due to rapid urbanization, industrialization, agricultural development, and mining activities, soil heavy metal pollution has become a severe issue in China. To explore the regional heavy metal ecological risk of lake sediment and surrounding topsoil, we analyzed 237 lakes, with 1797 lake sediment sampling points and 1164 surrounding topsoil sampling points. Lower mean concentrations were detected for most heavy metals in soils than sediment (except for Hg). Cd and Hg in sediments and soils showed a more significant variation, with the coefficient of variation exceeding 110%. Linear regressions and Pearson's correlation analyses demonstrated that sediments and soils exhibited significant positive correlations. The principal heavy metals exceeding the Agricultural Soil Control Standard (ASCS) in sediments and soils were As and Cd, respectively. The Yunnan-Guizhou Plateau Lake Region (YGPLR) was the most seriously affected, exceeding the ASCS for Cd. The lakes with the most severe pollution were located in YGPLR impacted by the high background concentration of heavy metals in soil and mineral development activities. The Eastern Plain Lake Region, the Southeast Lake Region, and the Northeast Plain and Mountain Lake Region showed a clear anthropogenic impact. Lakes in the Inner Mongolia-Xinjiang Lake Region and the Tibetan Plateau Lake Region were estimated to have relatively low ecological risks due to their sparse population and slight environmental disturbance. The impact of geochemical factors on the ecological risk of heavy metals in lake sediments is more substantial than that of human activities at the regional scale. [ABSTRACT FROM AUTHOR]

Sodium silicate is one of the common alkali activators of geopolymers. The modulus, concentration and dosage of sodium silicate have significant effects on the activation of fly ash, the strength and microstructure of geopolymer. In this paper, unconfined compressive strength test, X-ray diffraction analysis (XRD), Fourier transform infrared light (FTIR), 29Si nuclear magnetic resonance (29Si NMR), scanning electron microscope and energy disperse spectroscopy (SEMEDS), and physisorption experiment (BET) were carried out to study the effects of the sodium silicate modulus and dosage on the mechanical property and microstructure of fly ash-based geopolymer. The results indicated that the main product of the geopolymer activated by sodium silicate was hydrated sodium aluminosilicate (N-A-S-H). When modulus value decreased and meanwhile dosage of sodium silicate increased, the reorganization and polymerization of gel products were accelerated so that the integrity and continuity of the microstructure of geopolymer were improved, and then the strength increased. When the modulus of sodium silicate was 3.28, the maximum value of the strength was at the dosage of 10%. According to this study, it was investigated that modulus value and dosage of sodium silicate had obvious influence on the alkali- activated reaction of fly ash, which can provide an engineering reference for the special soil solidification with geopolymers. [ABSTRACT FROM AUTHOR]

Flaky FexHoNi2−x alloy powders were prepared by vacuum arc-melting and high-energy ball milling. The influences of different Fe substitutions on the surface morphology and microwave absorption properties of the alloy, the influence of alloy thickness on the microwave wave absorbing property, and the effects of magnetic loss and electrical loss on the absorbing properties were studied. The results showed that doping Fe in HoNi2 alloy powders enhanced the electrical and magnetic loss properties and optimized the microwave absorption properties. When the alloy matching thickness was 2.0 mm, the absorption peak moved to a lower frequency with an increase in Fe content and the maximum reflection loss was − 21.2 dB. From the investigation, when the Fe content was 0.4 and thickness was 2.1 mm, the microwave absorption performance reached the minimum value of − 22.6 dB at 7.2 GHz, which allowed a good microwave absorption performance in the C band. [ABSTRACT FROM AUTHOR]

The main challenges for programmed cell death 1(PD-1)/PD-1 ligand (PD-L1) checkpoint blockade lie in a lack of sufficient T cell infiltration, tumor immunosuppressive microenvironment, and the inadequate tumor accumulation and penetration of anti-PD-1/PD-L1 antibody. Resetting tumor-associated macrophages (TAMs) is a promising strategy to enhance T-cell antitumor immunity and ameliorate tumor immunosuppression. Here, mannose-modified macrophage-derived microparticles (Man-MPs) loading metformin (Met@Man-MPs) are developed to efficiently target to M2-like TAMs to repolarize into M1-like phenotype. Met@Man-MPs-reset TAMs remodel the tumor immune microenvironment by increasing the recruitment of CD8+ T cells into tumor tissues and decreasing immunosuppressive infiltration of myeloid-derived suppressor cells and regulatory T cells. More importantly, the collagen-degrading capacity of Man-MPs contributes to the infiltration of CD8+ T cells into tumor interiors and enhances tumor accumulation and penetration of anti-PD-1 antibody. These unique features of Met@Man-MPs contribute to boost anti-PD-1 antibody therapy, improving anticancer efficacy and long-term memory immunity after combination treatment. Our results support Met@Man-MPs as a potential drug to improve tumor resistance to anti-PD-1 therapy. Durable response rate to anti-PD-1/PD-L1 therapy remains relatively low in patients with cancer. Here the authors show that metformin-loaded mannose-modified macrophage-derived microparticles reprogram the tumor immune microenvironment and improve responses to anti-PD-1 therapy. [ABSTRACT FROM AUTHOR]

Inspired by the lock and key principle, the development of supramolecular macrocyclic chemistry has promoted the prosperous growth of host-guest chemistry. The updated induced-fit and conformation selection model spurred the emerging research on responsive macrocycles (RMs). This review introduces RMs, covering their design, synthesis and applications. It gives readers insight into the dynamic control of macrocyclic molecules and the exploration of materials with desired functions. Macrocycles have been widely studied for their structure-specific and highly selective recognition properties. Here the authors review the design, synthesis and applications of photo-, pH- and redox-responsive macrocycles. [ABSTRACT FROM AUTHOR]

The Co2Y ferrite was prepared by sol–gel method, and its morphology, phase structure, magnetic, and electromagnetic parameters were investigated by related equipment. The results testified that the saturation magnetization which was measured by vibrating sample magnetometer (VSM) gradually decreases as the sintering temperature increases. The microwave absorbing peaks of Y-type ferrite moves to higher frequency with the rise of temperature. The minimum reflectivity value of the Y-type ferrite powder can achieve about −24.82 dB at 11.68 GHz with a thickness of 8.0 mm and the effective bandwidth (R < −10 dB) is 2.56 GHz. In addition, the microwave absorbing peaks of Nickel/Co2Y ferrite mixture moves to a lower frequency with the addition of nickel power. The minimum reflection loss value of mixture that consist of 40% nickel and 60% Y ferrite was −33.75 dB at 4.88 GHz (in the C-band) with the thickness of only 2.5 mm. These indicate that the combination of alloy powder and ferrite can improve the reflection loss value of ferrite at low thickness. Highlights: The saturation magnetization (Ms) of Co2Y ferrite, which was prepared by a sol-gel method, decreases from 54.46 to 48.04 emu/g with the increasing sintering temperature. The Co2Y ferrite prepared by a sol-gel method can reach the minimum reflection loss of −24.82 dB at 11.68 GHz with the thickness of 8.0 mm, and a bandwidth of R < −10 dB is 2.56 GHz. The optimum microwave absorption performance can be achieved for 40% nickel content, and a minimum reflection loss of −33.75 dB was obtained at 4.88 GHz with the thickness of 2.5 mm. [ABSTRACT FROM AUTHOR]

Chrysopogon zizanioides is a perennial C4 grass that has been widely utilized for soil erosion control and ecological restoration. Nevertheless, genomic information of C. zizanioides is currently unavailable. Here, we firstly conducted a genome survey of C. zizanioides to obtain its repeatome information through next generation sequencing (NGS) and RepeatExplorer analysis. As a result, the estimated genome size of C. zizanioides was about 880 Mb, the heterozygosity rate was calculated to be 0.80%, the repeat content was 62.08%, and the GC content was 44.71%. Nine different repeat families were identified in the C. zizanioides genome, Ty3/Gypsy retrotransposons represented the dominant family and demonstrated greater diversity than Ty1/Copia retrotransposons, and two C. zizanioides rDNAs displayed high conservation in the genic coding regions and high polymorphism in the intergenic spacer regions. Overall, these results enhanced our understanding of the C. zizanioides genome, and provided a large amount of genomic resources for further excavation and utilization of C. zizanioides. [ABSTRACT FROM AUTHOR]

We investigate the global distribution of hourly precipitation and its connections with the El Niño–Southern Oscillation (ENSO) using both satellite precipitation estimates and the global sub-daily rainfall gauge dataset. Despite limited moisture availability over continental surfaces, we find that the highest mean and extreme hourly precipitation intensity (HPI) values are mainly located over continents rather than over oceans, a feature that is not evident in daily or coarser resolution data. After decomposing the total precipitation into the product of the number of wet hours (NWH) and HPI, we find that ENSO modulates total precipitation mainly through the NWH, while its effects on HPI are more limited. The contrasting responses to ENSO in NWH and HPI is particularly apparent at the rising branches of the Pacific and Atlantic Walker Circulations, and is also notable over land-based gauges in Australia, Malaysia, the USA, Japan and Europe across the whole distribution of hourly precipitation (i.e. extreme, moderate and light precipitation). These results provide new insights into the global precipitation distribution and its response to ENSO forcing. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD) affects a large population and is closely associated with cognitive impairment. However, the mechanisms of cognitive impairment in COPD patients have not been unraveled. This study investigated the change in patterns of intrinsic functional hubs using a degree centrality (DC) analysis. The connectivity between these abnormal hubs with the remaining brain was also investigated using functional connectivity (FC). Nineteen stable patients with COPD and 20 normal controls(NC) underwent functional magnetic resonance imaging (MRI) examinations and clinical and neuropsychologic assessments. We measured the voxel-wise DC across the whole brain gray matter and the seed-based FC between these abnormal hubs in the remaining brain matter; the group difference was calculated. A partial correlation analysis was performed to assess the relationship between the abnormal DC and clinical variables in COPD patients. Compared to NC, the patients with COPD exhibited significantly decreased DC in the right lingual gyrus (LG), bilateral supplementary motor area (SMA), and right paracentral lobule (PCL). A further seed-based FC analysis found that COPD patients demonstrated significantly decreased FC between these abnormal hubs in several brain areas, including the left cerebellum anterior lobe, left lingual gyrus, left fusiform gyrus, right insula, right inferior frontal gyrus, limbic lobe, cingulate gyrus, left putamen, lentiform nucleus, right precuneus, and right paracentral lobule. A partial correlation analysis showed that the decreased DC in the right PCL was positively correlated with the FEV1 and FEV1/FVC, and the decreased DC in the SMA was positively correlated with naming and pH in COPD patients. This study demonstrates that there are intrinsic functional hubs and connectivity alterations that may reflect the aberrant information communication in the brain of COPD patients. These findings may help provide new insight for understanding the mechanisms of COPD-related cognitive impairment from whole brain functional connections. [ABSTRACT FROM AUTHOR]

There is an urgent need for high-quality and high-spatial-resolution hourly precipitation products around the globe, including the UK. Although hourly precipitation products exist for the UK, these either contain large errors, or are insufficient in spatial resolution. An efficient way to solve this is to develop a merged precipitation product that combines the information and benefits from multiple data sources, improving both the spatial resolution and accuracy of hourly precipitation estimates over the UK. In this study, we develop a UK high-resolution gauge–radar–satellite merged hourly precipitation analysis: the UKGrsHP. It covers the UK from 12.5° W to 3.5° E, 49° N–60° N, with a spatial resolution of 0.01° × 0.01° in latitude/longitude (equivalent to 1 km resolution in the mid-latitudes). An optimal interpolation (OI)–based multi-source merging scheme with compound strategy is developed and tested for producing the UKGrsHP. Three input data sources are used: gauge analysis data interpolated from 1903 quality-controlled hourly observations, the UK Nimrod radar precipitation analysis and the GSMaP global satellite precipitation analysis. Using independent tests against ~ 220 independent gauge observations on 1 year's experimental UKGrsHP, covering the period from January to December 2014, we find that the final merged data performs better than three individual precipitation analyses used as inputs. A full version of the UKGrsHP starting in April 2004 is now under production, which will have wide applications in climate services and scientific research across multiple disciplines. [ABSTRACT FROM AUTHOR]

The "Western Tibetan Vortex" (WTV)—also termed the Karakoram Vortex—dominates the middle-to-lower troposphere and the near-surface air temperature variability above the western Tibetan Plateau (TP). Here, we explore the thermodynamic mechanisms through which the WTV modulates air temperature over the western TP by diagnosing the three major terms of the thermodynamic energy equation—adiabatic heating, horizontal temperature advection, and diabatic heating—that maintain the atmospheric thermal balance. We composite these major terms to examine the differences between anti-cyclonic and cyclonic WTV events. Our theoretical approach demonstrates that adiabatic sinking-compression (rising-expansion) provides the overwhelming control on both the middle-to-lower tropospheric and lower stratospheric temperature increases (decreases) under anti-cyclonic (cyclonic) WTV conditions over the western TP high mountain area in all four seasons. This also explains the mechanisms behind the anomalous temperature "dipole" found between the mid-lower troposphere and lower stratosphere when the WTV was initially identified. Spatially, adiabatic heating effects are centred on the central western TP in summer and the south slope centring at 70°–80°E of the TP in other seasons. The other two terms, horizontal temperature advection and diabatic heating, have localized importance over the edges of the western TP. In a case study over the Karakoram area, we further demonstrate that adiabatic heating (rising-expanding-cooling/sinking-compressing-warming) is the dominant thermodynamic process controlling Karakoram air temperatures under WTV variability, except for at the very near surface in autumn and winter. Our analysis methods can be applied to investigate the thermodynamic processes of other atmospheric circulation systems or climate variability modes. [ABSTRACT FROM AUTHOR]

Purpose: Developing animal models for human diseases is critical for studying complex diseases such as type 2 diabetes mellitus (T2DM). Since inbred colonies of Chinese hamsters tend toward spontaneous development of diabetes, we investigated them as a possible model. Methods: We regarded individuals with fasting blood glucose (FBG) higher than 6.0 mmol/L and post-prandial blood glucose (PBG) higher than 7.0 mmol/L as diabetic based on the mean and 95% frequency distribution values of FBG and PBG. Diabetic hamsters were characterized based on metabolic profiles, histopathological features, and changes in the expression of genes involved in glucose and lipid metabolism. Results: Metabolic analyses showed that diabetic hamsters exhibited mild hyperglycemia, hypertriglyceridemia, glucose intolerance, and insulin resistance. Histopathological analysis revealed that cell nuclei migrated inward in skeletal muscle and obvious partial liver lipid deposition and focal necrosis was found. We additionally observed mild injury, atrophy, and occasional vacuolization in islet cells. Changes in the expression of several genes related to glucose and lipid metabolism were observed. Decreased expression of adiponectin and GLUT4 and increased expression of PPARγ, Akt, and leptin was observed in skeletal muscle. Decreased expression of adiponectin with increased expression of PPARγ and leptin was observed in the liver. Conclusions: These results indicate that we have established a spontaneous diabetic hamster line that closely mimics human T2DM, which may hold potential for further research on the pathogenesis and treatment of this disease. [ABSTRACT FROM AUTHOR]

Flaky microwave absorbing materials based on Ce2Co17 with different addition of Ni content were fabricated successfully using the method of vacuum arc melting and high energy ball milling. The phase structure, grain morphology, electromagnetic parameters and reflection loss (RL) were probed by the corresponding equipment and computational simulation software. The RL values of Ce2Co17−xNix alloys that exceeded − 10 dB were observed in the frequency range of 6.16-10.24 GHz with a thickness of only 1.8 mm. Besides, via adjusting the thickness to only 1.6 mm, the minimum RL of Ce2Co16.6Ni0.4 powder was as high as − 44.29 dB at 9.6 GHz with a broad bandwidth of 3.04 GHz. Furthermore, the different weight ratio for Ce2Co16.6Ni0.4/carbonyl iron powder composite was also studied. The microwave absorption peak of composite shifts to a higher frequency region with the increasing weight ratio of carbonyl iron powder. More importantly, the effective bandwidth of the composite with the Ce2Co16.6Ni0.4/carbonyl iron powder weight ratio of 50:50 can be obtained at about 4.64 GHz, manifesting that composite can be provided with excellent microwave absorption bandwidth by adjusting the weight ratio of carbonyl iron powder. [ABSTRACT FROM AUTHOR]

The Al8Mn5 − xLax (x = 0, 0.2, 0.6, 1.0) powders were triumphantly manufactured by vacuum melting and planetary mill equipment. The influences of La content on phase constitution, morphology, saturation magnetization, and electromagnetic parameters were investigated by related equipment. The consequences demonstrate that Al8Mn4La phase, average size of particulate increases and the saturation magnetization (Ms) decreases as La content increased. The minimum reflectivity of Al8Mn4.4La0.6 powder reaches about −43.5 dB in the range of 10.8 to 11.7 GHz, and the effective bandwidth (RL < − 10 dB) can obtain about 1.70 GHz with the best matching thickness of 1.8 mm. These manifest Al8Mn5-xLax (x = 0, 0.2, 0.6, 1.0) powders possess the capacity to be excellent microwave absorbing materials. [ABSTRACT FROM AUTHOR]

For a fixed number of microphones, array geometry is the dominant factor to affect beamforming performance for speech signals in immersive environment. Our work, therefore, focuses on the relationship between microphone distribution properties and spatial filtering performance. Array geometries for immersive environments are statistically analyzed to specify the important mic density parameters related to array performance. Feasible optimization algorithms were proposed with the objective function rules using relationship functions and probabilistic descriptions of acoustic scenes to incorporate various levels of prior knowledge of the source distribution. General guidelines in real scenarios were introduced to effectively control the mic distribution parameters related to microphone density, and directly build arrays with superior SNR performance. In addition, arrays mutated from the regular configurations were also introduced to overcome the limitations of regular arrays, and provide good SNR results for speech signals with easily installation. [ABSTRACT FROM AUTHOR]

The RexCe2−xCo17 (Re = Dy, Pr, x = 0, 0.1, 0.2, 0.4) alloy was prepared by a combination use method of arc melting and high-energy ball milling and the phase structure, morphology and electromagnetic parameters were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and vector network analyzer (VNA), respectively. The consequences demonstrate that the particle size has a decreasing tendency and the minimum absorption peak frequency offsets to a low frequency band with increasing Re (Dy, Pr). The reflectivity of DyxCe2−xCo17 (x = 0, 0.1, 0.2, 0.4) alloy increase first and then decrease with the addition of Dy content, and the Dy0.2Ce1.8Co17 alloy can achieve the minimum RL of − 39.16 dB (microwave absorption rate 99.988%) at 8 GHz with the thickness of 1.8 mm. The microwave absorbing properties of PrxCe2−xCo17 (x = 0, 0.1, 0.2, 0.4) alloy can be optimized with the doping of Pr and the minimum RL of Pr0.2Ce1.8Co17 can reach to − 36.8 dB (microwave absorption rate 99.979%) at 7.92 GHz, and the bandwidth of R < − 10 dB is 2.24 GHz with the best matching thickness condition of 1.8 mm. [ABSTRACT FROM AUTHOR]

B Correction to: Climate Dynamics (2022) 58:2213-2225 b https://doi.org/10.1007/s00382-021-06001-6 In this article the Grant number needs to be added in the Acknowledgment section, so the text will read as follows: "This study is funded by Natural Science Foundation of China under Grants 42088101 and 42175026...". Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. The original article can be found online at https://doi.org/10.1007/s00382-021-06001-6. [Extracted from the article]

A novel natural deep eutectic solvent (NADES) composed of choline chloride (ChCl) and sesamol was prepared for the first time and was successfully employed in ultrasonic-assisted liquid-liquid microextraction (UALLME) of tert-butylhydroquinone (TBHQ) from soybean oils in the present study. In a typical experiment, 400 μL NADES as extraction solvent was added to a sample containing 0.2 g soybean oil, and then ultrasonic-assisted extraction was applied. After centrifugation, NADES phase containing TBHQ was directly analyzed by reverse phase high-performance liquid chromatography-ultraviolet detector (HPLC-UV), and no phase inversion was involved, which can satisfy the rapid sample pretreatment process. Under optimized condition, TBHQ showed a linear calibration curve in the range of 5~500 mg/kg (r2 = 0.9999) and lower limit of detection (LOD) of 0.02 μg/mL. The recoveries were in the range of 93.4~108.8%, and the intra-day and inter-day precision were less than 2.3%. This method was successfully applied to the determination of TBHQ in ten soybean oil samples, in which the results were close to that for conventional liquid-liquid extraction with methanol as solvent. Moreover, this sesamol-based NADES exhibited good protection ability to TBHQ during the extraction process due to the original antioxidant activity of sesamol. [ABSTRACT FROM AUTHOR]

BiO is a polymorphic material with δ phase most known for its highest oxide ion conductivity. In this work, BiO thin films were prepared by sol-gel technique with annealing temperature of 450 and 550 °C. Electrochromic performances of the films were inspected. It discovered that the color state of the BiO thin films switched between black and light yellow transparent when applying a voltage of −2 ~ 2 V. Electrochromic degradation was further observed in the thin films. However, steadier electrochromic efficiency was found in the film annealed at higher temperature. This could be related to the larger δ-BiO phase fraction which may contribute to higher conductivity and show positive electrochromic effect. Graphical abstract: BiO is a polymorphic material with δ phase most known for its highest oxide ion conductivity. In this work, BiO thin films were prepared by sol-gel technique with annealing temperature of 450 and 550 °C. Electrochromic (EC) performances of the films were inspected. It discovered that the color state of the BiO thin films switched between black and light yellow transparent when applying a voltage of −2 ~ 2 V. EC degradation was further observed in the thin films. However, steadier EC efficiency was found in the film annealed at higher temperature. This could be related to the larger δ-BiO phase fraction which may contribute to higher conductivity and give a positive EC result. [ABSTRACT FROM AUTHOR]

In this study, the effects of pre-oxidants permanganate (PM), persulfate (PS), hydrogen peroxide (PO), and ozone (OZ)) and/or adsorption on pseudoboemite-chitosan shell magnetic nanoparticles (ACMNs) on haloacetonitrile (HAN) and trichloronitromethane (TCNM) formation from aspartic acid (Asp; positive charge) and/or histidine (His; negative charge) were compared. Asp and His apparently do not interact in aqueous solution during chlorination. Asp and/or His can undergo partially oxidation by PM, but are recalcitrant to direct oxidation by PS and PO. Pre-oxidation with OZ decreases the formation of HANs but increases the formation of TCNM. ACMN prefers to adsorb Asp over His in the competitive sorption of coexisting Asp and His because of attractive electrostatic interactions. The rank order for the effect of the pre-oxidants and ACMN adsorption on dichloroacetonitrile and trichloroacetonitrile formation is OZ and ACMN adsorption > PM and ACMN adsorption > PS and ACMN adsorption > PO and ACMN adsorption; that for the effect of the pre-oxidants and ACMN adsorption on TCNM formation is PM and ACMN adsorption > PS and ACMN adsorption > PO and ACMN adsorption > OZ and ACMN adsorption. The favored adsorption of Asp over His by ACMN is weakened by pre-oxidation. [ABSTRACT FROM AUTHOR]

A green and inexpensive ultrasonic-assisted liquid-liquid microextraction (UALLME) technique based on deep eutectic solvents (DESs) was employed in the extraction and separation of tert-butylhydroquinone (TBHQ) from edible oils. In a typical experiment, 400 μL DES as extraction solvent was added to 3.0 mL sample solution containing 0.15 g edible oil, and then ultrasonic-assisted extraction was applied. After centrifugation, DES phase containing TBHQ was directly analyzed by reverse phase high-performance liquid chromatograph-ultraviolet detector (HPLC-UV) and no phase inversion was involved, which can simplify the sample pretreatment process. Under optimized condition, TBHQ showed a linear calibration curve in the range of 5∼500 mg/kg ( r = 0.9998) and lower limit of detection (LOD) of 0.02 μg/mL. The recoveries were in the range of 98.5∼112%, and the intraday and inter-day precision were less than 3.2%. This method was successfully applied to the determination of TBHQ in 13 edible oil ( e.g., soybean oil, blend oil) samples, which the result was close to that for conventional liquid-liquid extraction with methanol as solvent. [ABSTRACT FROM AUTHOR]

A diamond-like carbon film doped with TiC nanocrystallites (TiC-DLC) with a thickness of 35.8 μm was successfully prepared on a stainless steel substrate by employing a combination of metal vapor vacuum arc and filtered cathode vacuum arc techniques. A maximum deposition rate of 0.25 μm/min was achieved for TiC-DLC films. The structure and properties of the TiC-DLC films were systematically analyzed using different methods such as transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, X-ray diffraction, and friction and wear tests. The results indicated that typical a-C:H films containing nano-sized TiC grains were deposited which exhibit improved mechanical properties such as high cohesive strength, Vickers hardness, and capacity against high temperature. Parameter windows for CH flow rate and solenoid current were also provided for the deposition of TiC-DLC films to meet the requirements for using the material for specific commercial applications. [ABSTRACT FROM AUTHOR]

We show that a strongly enhanced coupling of spatially propagating electromagnetic waves to self-guiding unidirectional edge states (UESs) can be achieved by engineering a magnetic plasmonic gradient metasurface (GMS) made of an array of ferrite rods. The conversion efficiency of the incident photons into self-guiding UESs exhibits a transition from zero on an ordinary periodic surface to nearly 80 % on a surface incorporating a GMS. The underlying physics lies in that the magnetic plasmonic GMS enables a direct excitation of the edge states due to the band-folding or momentum compensation effect, which are in turn transformed into the self-guiding UESs on the ordinary periodic surface. The excitation of the UESs can also be revealed by considering the partial wave scattering amplitudes of the constituent rods on the surface, which manifests a change from a standing wave in the region subject to an external illumination to a self-guiding wave propagating and confined on the surface, a signature of UESs. The magnetic plasmonic GMS can also be used to implement the unidirectional phase control of the UES and the nonreciprocal Goos-Hänchen shift as a consequence of the time-reversal-symmetry breaking nature of the system and the strong coupling of the incident wave. In addition, the unidirectional features are shown to be flexibly controlled by either tailoring the gradient or tuning the external magnetic field, adding considerably to the performance of the magnetic plasmonic GMS systems. [ABSTRACT FROM AUTHOR]

8-Oxoguanosine (8-oxoGuo), 8-oxo-2′-deoxyguanosine (8-oxo-dG) and 8-iso-prostaglandin F2α (8-iso-PGF2α) are widely used noninvasive and effective biomarkers of oxidative damage to RNA, DNA and lipids. These three compounds are usually analyzed with different methods because of their different polarity and MS detection modes. In this paper, a sensitive and rapid UHPLC-MS/MS method to determine 8-oxoGuo, 8-oxo-dG and 8-iso-PGF2α in human urine was developed in order to evaluate the oxidative damage of DNA, RNA and lipid peroxidation. With this method, 8-oxoGuo, 8-oxo-dG and 8-iso-PGF2α could be conveniently and separately eluted with different elution solvent on the same Agilent Bond C18 solid-phase column; the two obtained eluates are detected through two injections using the same HPLC column and mobile phase for the determination of 8-oxoGuo, 8-oxo-dG and 8-iso-PGF2α in positive and negative ESI mode, respectively. The limits of detection and quantitation of the three biomarkers approached to 0.04-0.17 ng mL and 0.13-0.57 ng mL, respectively. The intraday and interday precisions of all compounds were at most 10%. The method was applied to analyze urine samples from 40 smokers and 20 nonsmokers to evaluate the effect of cigarette smoking on oxidative stress. The results showed that concentrations of the three compounds in the urine of smokers are higher than those in nonsmokers, indicating the increased oxidative stress effect of smoking. [ABSTRACT FROM AUTHOR]

A serial-parallel dynamics simulator based on serial-parallel manipulator is proposed. According to the dynamics simulator motion requirement, the proposed serial-parallel dynamics simulator formed by 3-RRS (active revolute joint-revolute joint-spherical joint) and 3-SPR (Spherical joint-active prismatic joint-revolute joint) PMs adopts the outer and inner layout. By integrating the kinematics, constraint and coupling information of the 3-RRS and 3-SPR PMs into the serial-parallel manipulator, the inverse Jacobian matrix, velocity, and acceleration of the serial-parallel dynamics simulator are studied. Based on the principle of virtual work and the kinematics model, the inverse dynamic model is established. Finally, the workspace of the (3-RRS)+(3-SPR) dynamics simulator is constructed. [ABSTRACT FROM AUTHOR]

In this research, we monitored the change (degeneration or improvement) in meadow vegetation over an approximately 12-year timespan in the typical steppe area of Inner Mongolia in China. Linear trend analysis (LTA) and the MOD13Q1-NDVI time series data were used to evaluate the changes in the net primary productivity (NPP) during the vegetation growing seasons between 2000 and 2011. The Carnegie Ames Stanford Approach (CASA) model was used, and the relationship between the vegetation change and meadow NPP was analyzed and validated with field data collected in 2011. The results indicate the following: (1) the growth status and NPP of the meadow vegetation in the typical steppe area of Inner Mongolia varied greatly for each year without an obvious linear trend between the change of meadow vegetation and NPP; (2) additional analysis with field measured data, collected in 2011, revealed that the average dry weight of the above-ground biomass in the area where the NPP had increased was less than that in the area where it had decreased; the dry weight of the above-ground biomass of the meadow vegetation that showed degeneration was greater than that of the meadow vegetation that showed improvement; (3) a possible reason for the phenomenon mentioned in (2) was that the government protected the degenerated meadows with less biomass, which led to vegetation growth and increased NPP, whereas the meadows that had not been degenerated or showed only minor degeneration and still received rich biomass were over-grazed, causing the NPP to decline. [ABSTRACT FROM AUTHOR]

In this paper, a sensitive accurate method for the determination of heterocyclic aromatic amines (HAAs) in cigarette smoke has been developed and validated using solid-phase extraction coupled with liquid chromatography-tandem mass spectrometry. A calibration curve was obtained with representative cigarette smoke using the standard addition method to compensate for matrix effects because the smoke of different cigarettes shows similar matrix effects. With this method, the accuracy of the method can be improved using a common analog of HAAs, which will greatly reduce the expense of using an isotope-labeled internal standard. Validation results showed that the method has high sensitivity (quantification limits of 0.08-0.56 ng cig), good reproducibility (RSD 6.37-9.31 %) and satisfactory recoveries (81.0-111 %). With this method, the emissions of HAAs in 30 commercial cigarette samples were analyzed and compared. [ABSTRACT FROM AUTHOR]

Numerical experiments with different idealized land and mountain distributions are carried out to study the formation of the Asian monsoon and related coupling processes. Results demonstrate that when there is only extratropical continent located between 0 and 120°E and between 20/30°N and the North Pole, a rather weak monsoon rainband appears along the southern border of the continent, coexisting with an intense intertropical convergence zone (ITCZ). The continuous ITCZ surrounds the whole globe, prohibits the development of near-surface cross-equatorial flow, and collects water vapor from tropical oceans, resulting in very weak monsoon rainfall. When tropical lands are integrated, the ITCZ over the longitude domain where the extratropical continent exists disappears as a consequence of the development of a strong surface cross-equatorial flow from the winter hemisphere to the summer hemisphere. In addition, an intense interaction between the two hemispheres develops, tropical water vapor is transported to the subtropics by the enhanced poleward flow, and a prototype of the Asian monsoon appears. The Tibetan Plateau acts to enhance the coupling between the lower and upper tropospheric circulations and between the subtropical and tropical monsoon circulations, resulting in an intensification of the East Asian summer monsoon and a weakening of the South Asian summer monsoon. Linking the Iranian Plateau to the Tibetan Plateau substantially reduces the precipitation over Africa and increases the precipitation over the Arabian Sea and the northern Indian subcontinent, effectively contributing to the development of the South Asian summer monsoon. [ABSTRACT FROM AUTHOR]

Unlike a Bézier curve, a spline curve is hard to be obtained through geometric corner cutting on control polygons because the degree elevation operator is difficult to be obtained and geometric convergence is hard to be achieved. In order to obtain geometric construction algorithm on C-B-splines, firstly we construct the degree elevation operator by using bi-order splines in this paper. Secondly we can obtain a control polygon sequence by degree elevation based on the degree elevation operator derived from a C-B-spline curve. Finally, we prove that this polygon sequence will converge to initial C-B-spline curve. This geometric construction algorithm possesses strong geometric intuition. It is also simple, stable and suitable for hardware to perform. This algorithm is important for CAD modeling systems, since many common engineering curves such as ellipse, helix, etc. can be represented explicitly by C-B-splines. [ABSTRACT FROM AUTHOR]