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The rise and development of Left-wing literature in Brazil is closely connected to the obstacles and dilemmas encountered during the evolution of its nation, and it is also inseparable from international political movements and intellectual trends. From the abolishment of slavery and collapse of empire in the nineteenth century, to the establishment and return of dictatorship in the 30s and 60s of the twentieth century, at every moment of crisis, Brazilian left-wing literature always played a seminal role. While criticizing social injustices, it also invigorates the development of modern Brazilian literature by incorporating different forms of language, thoughts and art. It is safe to say that left-wing literature forms a kind of literary tradition in Brazil, as it not only represents a moral and ethical stand, but also innovates the form and aesthetics.

IntroductionAnti-PD-1/PD-L1 inhibitors therapy has become a promising treatment for hepatocellular carcinoma (HCC), while the therapeutic efficacy varies significantly among effects for individual patients are significant difference. Unfortunately, specific predictive biomarkers indicating the degree of benefit for patients and thus guiding the selection of suitable candidates for immune therapy remain elusive.no specific predictive biomarkers are available indicating the degree of benefit for patients and thus screening the preferred population suitable for the immune therapy. MethodsUltra-high-pressure liquid chromatography-mass spectrometry (UHPLC-MS) considered is an important method for analyzing biological samples, since it has the advantages of high rapid, high sensitivity, and high specificity. Ultra-high-pressure liquid chromatography-mass spectrometry (UHPLC-MS) has emerged as a pivotal method for analyzing biological samples due to its inherent advantages of rapidity, sensitivity, and specificity. In this study, potential metabolite biomarkers that can predict the therapeutic effect of HCC patients receiving immune therapy were identified by UHPLC-MS. ResultsA partial least-squares discriminant analysis (PLS-DA) model was established using 14 glycerophospholipid metabolites mentioned above, and good prediction parameters (R2 = 0.823, Q2 = 0.615, prediction accuracy = 0.880 and p < 0.001) were obtained. The relative abundance of glycerophospholipid metabolite ions is closely related to the survival benefit of HCC patients who received immune therapy. DiscussionThis study reveals that glycerophospholipid metabolites play a crucial role in predicting the efficacy of immune therapy for HCC.

Abstract IDH1 mutations frequently occur early in human glioma. While IDH1 mutation has been shown to promote gliomagenesis via DNA and histone methylation, little is known regarding its regulation in antiviral immunity. Here, we discover that IDH1 mutation inhibits virus-induced interferon (IFN) antiviral responses in glioma cells. Mechanistically, D2HG produced by mutant IDH1 enhances the binding of DNMT1 to IRF3/7 promoters such that IRF3/7 are downregulated, leading to impaired type I IFN response in glioma cells, which enhances the susceptibility of gliomas to viral infection. Furthermore, we identify DNMT1 as a potential biomarker predicting which IDH1mut gliomas are most likely to respond to oncolytic virus. Finally, both D2HG and ectopic mutant IDH1 can potentiate the replication and oncolytic efficacy of VSVΔ51 in female mouse models. These findings reveal a pivotal role for IDH1 mutation in regulating antiviral response and demonstrate that IDH1 mutation confers sensitivity to oncolytic virotherapy.

Geralmente se supõe que a tradução da literatura brasileira nos primeiros anos da República Popular da China (1949-1966) foi principalmente impulsionada por forças políticas, devido às mudanças ideológicas oficiais e nas reformas do sistema editorial naquela época. No entanto, este argumento não leva em conta a continuidade da tradução literária antes e depois de 1949, nem considera o esforço dos tradutores naquela época em escolherem os melhores representantes da literatura brasileira e conservarem ao máximo a qualidade das obras originais. Ao analisar a tradução da literatura brasileira na China de 1919 a 1966 como um todo, com revisão especial do caso de Jorge Amado, este artigo tenta demonstrar que a publicação da literatura brasileira após 1949 seguiu o mesmo caminho da tradução da literatura das nações desfavorecidas na primeira metade do Século XX, e que tinha como objetivo de quebrar a hegemonia cultural dos países ocidentais, a fim de construir uma nova nação e uma nova literatura.

Summary: Immune checkpoint blockade therapies are still ineffective for most patients with colorectal cancer (CRC). Immunogenic cell death (ICD) enables the release of key immunostimulatory signals to drive efficient anti-tumor immunity, which could be used to potentiate the effects of immune checkpoint inhibitors. Here, we showed that inhibition of valosin-containing protein (VCP) elicits ICD in CRC. Meanwhile, VCP inhibitor upregulates PD-L1 expression and compromises anti-tumor immunity in vivo. Mechanistically, VCP transcriptionally regulates PD-L1 expression in a JAK1-dependent manner. Combining VCP inhibitor with anti-PD1 remodels tumor immune microenvironment and reduces tumor growth in mouse models of CRC. Addition of oncolytic virus further augments the therapeutic activity of the combination regimen. Our study shows the molecular mechanism for regulating PD-L1 expression by VCP and suggests that inhibition of VCP has the potential to increase the efficacy of immunotherapy in CRC.

A strong ultraviolet pumping laser propagating through the atmosphere could activate the medium and produce the forward and backward coherent air lasing. In this work, we present the theoretical analyses of forward and backward lasing dynamics in the long gain medium consisting of oxygen atoms. By numerically solving the semiclassical Maxwell-Bloch equations, we demonstrate that the atom density, the gain medium length, and the collisional decoherence rate substantially regulate the forward and backward air laser radiation at 845 nm. Especially, our study points out that lower atom density and moderate collisional decoherence rate are favorable for the backward radiation amplification in a long medium, since such conditions balance the competing processes of forward and backward radiation fields. The simulation shows that long medium backward air lasing becomes challenging in the oxygen atom system via double-photon pump, because the amplification can only occur around z=0, and the amplified backward radiation does not carry the spectral information of atoms throughout the medium. On the other hand, certain mechanisms such as variation of backward-seeding delay could possibly alleviate the suppression of backward amplification.

Bloom filter (BF) is highly efficient for membership queries, which is widely used in blockchain mem-bership queries. Aiming at the existing BFs do not exploit the data characteristics of blockchain and the features of modern processors, this paper proposes a novel bloom filter variant named blockchain bloom filter (BBF). Firstly, this paper modifies data structure which divides BBF into groups, so that the mapping range of an element is limited into a group to reduce the number of cache misses and improve cache efficiency. Secondly, a simplified three-stage Hash process is presented to eliminate computing overhead by taking advantage of blockchain data characteristics. On this basis, BBF uses single instruction multiple data (SIMD) to parallelize element insertion and query, and accelerate BBF construction and query speed, which can realize efficient query and analysis of blockchain data ultimately. The experimental result shows that BBF??s membership query speed under positive query can improve 4 times and 3 times over the other two state-of-the-art bloom filter variants, i.e., BF, OMBF（one-memory bloom filter）, which enables significant performance improvement.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was initially described to target the respiratory system and now has been reported to infect a variety of cell types, including cardiomyocytes, neurons, hepatocytes, and gut enterocytes. However, it remains unclear whether the virus can directly infect human embryonic stem cells (hESCs) or early embryos. Herein, we sought to investigate this question in a cell-culture system of hESCs. Both the RNA and S protein of SARS-CoV-2 were detected in the infected hESCs and the formation of syncytium was observed. The increased level of subgenomic viral RNA and the presence of dsRNA indicate active replication of SARS-CoV-2 in hESCs. The increase of viral titers in the supernatants revealed virion release, further indicating the successful life cycle of SARS-CoV-2 in hESCs. Remarkably, immunofluorescence microscopy showed that only a small portion of hESCs were infected, which may reflect low expression of SARS-CoV-2 receptors. By setting |log2 (fold change)| > 0.5 as the threshold, a total of 1,566 genes were differentially expressed in SARS-CoV-2-infected hESCs, among which 17 interferon-stimulated genes (ISGs) were significantly upregulated. Altogether, our results provide novel evidence to support the ability of SARS-CoV-2 to infect and replicate in hESCs.

Depression and anxiety are common in patients with COPD (chronic obstructive pulmonary disease), and anxiety and depression can increase the risk of hospitalization and the acute exacerbation of chronic obstructive pulmonary disease. The relationship between the frequency of hospitalization for acute exacerbation of COPD (AECOPD) and the anxiety and depression of patients is not fully understood. This study aims to analyze the relationship between the frequency of hospitalizations and anxiety and depression of patients of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). A collection of 309 AECOPD patients admitted to the emergency department in our hospital from 2019 to 2020 were divided into anxiety group A and depression group D according to the Hospital Anxiety and Depression Scale (HADS) score and divided into A1 and D1 negative groups (≤7 Score), A2 and D2 suspicious groups (8–10 points), A3 and D3 confirmed groups (≥11 points) for paired analysis of anxiety and depression correlation and difference and comparison of the frequency of hospitalization in each group within 2 years. The results found that anxiety and depression were significantly positively correlated (r = 0.654, p = 0.000). Intra-group comparison shows that the difference between the anxiety-diagnosed and non-diagnosed groups and the depression subgroups are statistically p < 0.05; the comparison between the anxiety subgroup and the depression subgroup showed that there was a statistical difference between the confirmed group and the non-diagnosed group (p < 0.01). In short, AECOPD anxiety is positively correlated with depression, and depression is affected by the frequency of hospitalization earlier and gradually, and anxiety should be prioritized in the acute phase.

The rise and development of Left-wing literature in Brazil is closely connected to the obstacles and dilemmas encountered during the evolution of its nation, and it is also inseparable from international political movements and intellectual trends. From the abolishment of slavery and collapse of empire in the nineteenth century, to the establishment and return of dictatorship in the 30s and 60s of the twentieth century, at every moment of crisis, Brazilian left-wing literature always played a seminal role. While criticizing social injustices, it also invigorates the development of modern Brazilian literature by incorporating different forms of language, thoughts and art. It is safe to say that left-wing literature forms a kind of literary tradition in Brazil, as it not only represents a moral and ethical stand, but also innovates the form and aesthetics.

BACKGROUND Strategic critical metal mineral resources including rare, dispersed, rare earth and platinum group elements play an increasingly critical role in emerging industries such as new materials, new energy and information technology. With the deepening of the geological survey of key mineral resources in China, the critical metal elements present new challenges to analytical techniques due to their complex matrix, large differences in different mineral contents, and unstable chemical properties. OBJECTIVES To introduce recent analytical techniques and applications for critical metal elements in different types of geological samples. METHODS Based on different chemical composition, the main matrices of critical metal elements were classified, mainly divided into silicate, carbonate, sulfate, tungstate, phosphate, oxide, sulfide and halide. For different types of rocks and minerals, chemical digestion was largely carried out by traditional dissolution methods such as the acid dissolution method (nitric acid-hydrofluoric acid combination, aqua regia) or alkali fusion methods. RESULTS The characteristics and application of commonly used instruments including electronic probe microanalyzer, inductively coupled plasma-mass spectrometry, inductively coupled plasma-optical emission spectroscopy, and X-ray fluorescence spectroscopy were reviewed. The problems during critical metal analysis including incomplete dissolution, low recovery, oxides and isobaric interference, inconsistency between samples and standard matrices were reviewed and corresponding solutions were proposed. CONCLUSIONS In situ microanalysis with the advantages of high efficiency, low cost, and high spatial resolution, and field on-site geoanalysis with its simple, fast and close to field work features are the main trends in the development of critical metal elements analytical techniques.

Monoelemental two-dimensional materials are well known as Xenes. The representatives graphene and phosphorene have received considerable attention because of their outstanding physical properties. In recent years, the family members of Xenes have greatly increased, and the emerging ones are gaining more and more interest. In this review, we mainly focus on the recently developed Xenes in groups IIIA, VA, and VI. Comprehensive discussions of the latest progress are given in the aspects of basic physical properties and intriguing applications in photonics, optoelectronics, energy, and biomedicines.

PurposeColon cancer (CC) is a serious disease burden. The prognosis of patients with CC is different, so looking for effective biomarkers to predict prognosis is vitally important. Ferroptosis is a promising therapeutic and diagnosis strategy in CC. However, the role of ferroptosis in prognosis of CC has not been studied. The aim of the study is to build a prognosis model related ferroptosis, and provide clues for further therapy of CC.MethodsThe RNA-seq data were from TCGA (training group) and GEO (testing group). The R language and Perl language were used to process and analyze data. LASSO regression analysis was used to build the prognosis model. ssGSEA was used to compare the immune status between two groups. Immunohistochemistry was used to detect expression of AKR1C1 and CARS1 in colon cancer tissues and adjacent tissues.ResultsThe prognosis model consisted of five ferroptosis related genes (AKR1C1, ALOX12, FDFT1, ATP5MC3, and CARS1). The area under curve (AUC) at 1-, 2-, and 3-year were 0.668, 0.678, and 0.686, respectively. The high- and low-risk patients had significant survival probability and could be clearly distinguished by the PCA and t-SNE analysis. The multivariate cox regression analysis also showed the riskscore is an independent prognosis factor. Importantly, we found that the immune status between high- and low-risk patients were different obviously, such as CD8+T cells. And STING, a new promising immune target, was also correlated to our signature genes statistically significantly.ConclusionOur ferroptosis prognosis signature could predict survival of CC patients to a certain degree. And the crosstalk between ferroptosis and immune, especially STING need further studies.

Activation of the cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) pathway induces glial differentiation of glioblastoma (GBM) cells, but the mechanism by which microRNA (miRNA) regulate this process remains poorly understood. In this study, by performing miRNA genomics and loss‐ and gain‐of‐function assays in dibutyryl‐cAMP‐treated GBM cells, we identified a critical negative regulator, hsa‐miR‐1275, that modulates a set of genes involved in cancer progression, stem cell maintenance, and cell maturation and differentiation. Additionally, we confirmed that miR‐1275 directly and negatively regulates the protein expression of glial fibrillary acidic protein (GFAP), a marker of mature astrocytes. Of note, tri‐methyl‐histone H3 (Lys27) (H3K27me3), downstream of the PKA/polycomb repressive complex 2 (PRC2) pathway, accounts for the downregulation of miR‐1275. Furthermore, decreased miR‐1275 expression and induction of GFAP expression were also observed in dibutyryl‐cAMP‐treated primary cultured GBM cells. In a patient‐derived glioma stem cell tumor model, a cAMP elevator and an inhibitor of H3K27me3 methyltransferase inhibited tumor growth, induced differentiation, and reduced expression of miR‐1275. In summary, our study shows that epigenetic inhibition of miR‐1275 by the cAMP/PKA/PRC2/H3K27me3 pathway mediates glial induction of GBM cells, providing a new mechanism and novel targets for differentiation‐inducing therapy.

Ethylene glycol aqueous solution containing 0.5% NH _4 F was used as the electrolyte and the Ti foil was oxidized at 40 V for 30 min to obtain TiO _2 nanotube arrays with an inner diameter of about 85 nm. After heat treatment at 450 °C for 2 h, the TiO _2 nanotubes transformed from an amorphous phase to anatase, and a small percentage of the nanotubes collapsed. The Pt loaded by electrodeposition appeared at the nozzle of the nanotubes in a flake morphology.The best catalytic effect on methylene blue degradation was achieved by Pt loading with electrodeposition for 120 s.The methylene blue degradation rate reached 50% after 10 h of ultraviolet irradiation.

Oncolytic virotherapy is a promising strategy for cancer treatment. In this study, the authors demonstrate that DNA-dependent protein kinase (DNA-PK) inhibition sensitizes cancer cells to M1 virus and improves therapeutic effects in refractory cancer models in vivo and in patient tumour samples.

BACKGROUND The accurate determination of ionic phase rare earths in ion-adsorption rare earths is of great significance for the evaluation of rare earth ore bodies. Ionic phase rare earths are adsorbed on clay minerals in the form of hydroxyl or hydrated hydroxyls and can be exchanged and desorbed with strong electrolytes (Mg2+, NH4+, etc.) into solution. The former used ammonium sulfate as the leachate to achieve the desorption and extraction of rare earth ions in the ion phase, but the solution concentration, leaching process and other aspects of choice, leaching rates (60% to 90%) are different. There is no efficient and uniform leaching method conducive to the accurate determination of ionic phase rare earth elements. OBJECTIVES To establish a high-efficiency leaching process by ammonium sulfate solution and determine the accurate contents of ionic-phase rare earth elements. METHODS The leaching parameters (solid-to-liquid ratio, ammonium sulfate concentration, best sample weight, and soaking time) of rare-earth ions by ammonium sulfate were standardized through comparative experiments, which reduced the loss of ionic phase rare earth during leaching. The leaching rates were from 88% to 98%, and ICP-MS was used to accurately determine the ion phase rare earth component. RESULTS The detection limits are 0.05-5.11 ng/g, and the relative standard deviations (RSDs) are 1.80%-10.01% for volcanic rock, 1.06%-7.27% for metamorphic rock, and 1.72%-7.58% for sedimentary rock. CONCLUSIONS The analytical results of the collaborative laboratory verify the reliability and accuracy of the method. This method is easy to operate and has high analysis efficiency. It provides the base for the establishment of relevant industry standards and national standards.

Abstract Background Central pain (CP) is a common clinical problem in patients with spinal cord injury (SCI). Recent studies found the pathogenesis of CP was related to the remodeling of the brain. We investigate the roles of iron overload and subsequent microglia activate in the remodeling of the brain after SCI. Methods An SCI-induced CP model was established in Sprague-Dawley rats that were randomly assigned to SCI, sham operation, deferoxamine (DFX), minocycline, and nitric oxide synthase inhibitor treatment groups. At 12 weeks, pain behavior and thermal pain threshold were evaluated in each group, and iron transferrin receptor (TfR)1 and ferritin (Fn) mRNA, as well as iron-regulatory protein (IRP)1, FN, lactoferrin, and nuclear factor (NF)-κB protein levels in the rat brains were measured. Microglia proliferation and differentiation and IRP1 expression were evaluated by immunohistochemistry. Results Autophagy was observed in rats after SCI, accompanied by reduced latency of thermal pain, increased iron content and IRP1 and NF-κB levels in the hindlimb sensory area, hippocampus, and thalamus, and decreased Fn levels in the hindlimb sensory area. TfR1 mRNA expression was upregulated in activated microglia. Treatment with an iron-chelating agent, or inhibitors of nitric oxide synthase or microglia suppressed microglia proliferation. Conclusions SCI may induce intracranial iron overload, which activates microglia via NF-κB signaling. Microglia secrete inflammatory factors that induce neuronal damage and lead to CP. Treatment with an iron-chelating agent or NF-κB or microglia inhibitors can relieve CP resulting from SCI.

Summary: Glioblastoma multiforme (GBM) is among the most aggressive of human cancers. Although differentiation therapy has been proposed as a potential approach to treat GBM, the mechanisms of induced differentiation remain poorly defined. Here, we established an induced differentiation model of GBM using cAMP activators that specifically directed GBM differentiation into astroglia. Transcriptomic and proteomic analyses revealed that oxidative phosphorylation and mitochondrial biogenesis are involved in induced differentiation of GBM. Dibutyryl cyclic AMP (dbcAMP) reverses the Warburg effect, as evidenced by increased oxygen consumption and reduced lactate production. Mitochondrial biogenesis induced by activation of the CREB-PGC1α pathway triggers metabolic shift and differentiation. Blocking mitochondrial biogenesis using mdivi1 or by silencing PGC1α abrogates differentiation; conversely, overexpression of PGC1α elicits differentiation. In GBM xenograft models and patient-derived GBM samples, cAMP activators also induce tumor growth inhibition and differentiation. Our data show that mitochondrial biogenesis and metabolic switch to oxidative phosphorylation drive the differentiation of tumor cells. : Xing et al. show that the metabolic shift from glycolysis to oxidative phosphorylation drives differentiation of GBM cells into astrocytes by cAMP activation. Mechanistically, the cAMP-CREB-PGC1α signal mediates mitochondrial biogenesis, which leads to metabolic reprogramming, induced differentiation, and tumor growth inhibition. Keywords: glioblastoma, induced differentiation, Warburg effect, metabolic reprogramming, oxidative phosphorylation, glycolysis, mitochondrial biogenesis, cyclic adenosine monophosphate, cAMP, PPARγ coactivator-1α, PGC1α

Rhizoctonia solani, one of the most detrimental necrotrophic pathogens, causes rice sheath blight and poses a severe threat to production. Focus on the function of effectors secreted by necrotrophic pathogens during infection has grown rapidly in recent years. However, little is known about the virulence and mechanisms of these proteins. In this study, we performed functional studies on putative effectors in R. solani and revealed that AGLIP1 out of 13 putative effectors induced cell death in Nicotiana benthamiana. AGLIP1 was also demonstrated to trigger cell death in rice protoplasts. The predicted lipase active sites and signal peptide (SP) of this protein were required for the cell death-inducing ability. AGLIP1 was greatly induced during R. solani infection in rice sheath. The AGLIP1’s virulence function was further demonstrated by transgenic technology. The pathogenesis-related genes induced by pathogen-associated molecular pattern and bacteria were remarkably inhibited in AGLIP1-expressing transgenic Arabidopsis lines. Ectopic expression of AGLIP1 strongly facilitated disease progression in Arabidopsis caused by the type III secretion system-defective mutant from Pseudomonas syringae pv. tomato DC3000. Collectively, these results indicate that AGLIP1 is a possible effector that plays a significant role in pathogen virulence through inhibiting basal defenses and promoting disease development in plants.

Most of the mineral resources of lithium and potassium are distributed in remote western China. Fast, on-site analytical techniques are urgently needed for their exploration and comprehensive utilization. In this work, a newly developed portable Li-K analyzer was introduced for its analytical performance and the application of this equipment in determining lithium in spodumene is also discussed. The analyser is a type of atomic emission spectrometer based on solution cathode atmospheric glow discharge. Sample solution was used as a graphite cathode, which atomized and excited the elements Li and K. A charge coupled device (CCD) was used to detect the characteristic lines of Li and K, which had wavelengths ranging from 345 to 1015 nm with a 3 nm resolution. Using a Li analytical line of 670.78 nm and a K analytical line of 769.90 nm under the optimized working conditions, the measurement precisions for Li and K were greater than 2%RSD with the limit of detection of 0.03 μg/mL. Results show that different types and concentrations of acids strongly affect the intensities of Li and K, and co-existent elements produce serious matrix effect. Quantification of Li in spodumene ores by use of a calibration curve without matched matrix could not produce accurate results with relative standard deviation up to 267%. Standard addition methods can eliminate the influence of the matrix effect and obtain analytical results consistent with those by Inductively Coupled Plasma-Optical Emission Spectrometry, which thus provides a basis for on-site determination of Li in solid samples.

Presently, most studies focus on the minimization of the costs and negative social effects of the location of construction waste recycling centers; however, the influence of the location on future operation is usually ignored. Aiming at solving these problems, a location model for the maximization of service reliability was devised. Service reliability includes the recycling reliability of the construction waste and the delivery reliability of the recycled product. Through maximizing service reliability, the location deviation as a result of arrival delay is expected to be reduced and the service reliability improved. Then, two important parameters in our model were solved on the basis of correlative mathematical theories. Finally, an example was implemented to verify our location optimization model. A genetic algorithm was used to obtain optimal solutions, and the solutions were analyzed. Through establishing a location optimization model, a possible better solution to location problems may be obtained to help in implementing location selection for recycling centers.

Analysis of environmental water samples is primarily conducted in the laboratory, which costs considerable time and money. Pre-concentration methods coupled with portable X-ray Fluorescence (XRF) have been developed for the determination of almost twenty kinds of heavy metals, but with a relatively high detection limit, complex operation, and less element types can be measured using one pre-concentration strategy. All of these problems restrict the development of the technique. To solve these issues an on-site-oriented rapid and convenient analysis method of heavy metal ions in aqueous solutions has been developed utilizing a bench-top type portable Energy-Dispersive X-ray Fluorescence (EDXRF). Based on pre-concentration with purolite S930 chelating resin and thin-layer sample preparation technique, the method could determine trace V5+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and Pb2+ in environmental water samples. After the heavy metal ions have been absorbed by 20 mg of S-930 resin powder for about 30 min in the pH=4 solution, the resin powders are filtrated onto a 0.45 m filter to form a thin-layer sample which can be directly measured by EDXRF using a homemade double polypropylene film sample cup. With an amount of 100 mL of solution, the linear ranges were 10-1000 g/L and the correlation coefficients of the calibration curves were good (R2>0.997) for all the eight elements. The lower limit of detection was between 1.0 and 6.2 g/L. Precision tests carried out on multi-element mixed solutions showed that the relative standard deviations (RSD, n=12) were better than 5% except for those of Zn and Pb at the concentration level of 20 g/L. Most of the recoveries were 80%-120% with spikes of 20 g/L for each element. The analysis results of DW standard substances and simulation samples were consistent with reference values and the theoretical value respectively. This method skillfully uses a double polypropylene membrane preparation method to make a thin-layer film sample which solves the pollution problem and simplifies the pre-concentration steps. The resin film samples can be directly measured by XRF. A lower detection limit and better stability make the method suitable for a spot investigation, water quality monitoring, and assessment of Fe, Co, Ni, Cu, V, Zn, Mn and Pb in heavy metal polluted environmental water.