A novel colormetric and light-up fluorescent sensor from flavonol derivative grafted cellulose for rapid and sensitive detection of Hg2+ and its applications in biological and environmental system.

Mercury ion (Hg2+) is one of harmful heavy metal ions that can accumulate inside the human organism and cause some health problems. In the article, a highly effective fluorescent probe named EC-T-PCBM was prepared by grafting flavonol derivatives onto ethyl cellulose for the specific recognition of Hg2+. EC-T-PCBM exhibited a remarkable fluorescence light-up response toward Hg2+ with excellent sensitivity. EC-T-PCBM possessed several prominent sensing properties for Hg2+, such as low detection limit (43.9 nM), short response time (5 min), and wide detection pH range (6-9). The response mechanism of EC-T-PCBM to Hg2+ has been verified through 1H NMR titration and DFT computation. Additionally, EC-T-PCBM not only can be used for accurately determining trace amount of Hg2+ in actual environmental water samples, but also can serve as a portable and rapid device by loading it on test strips for sensitive and selective visualization of Hg2+. More importantly, the confocal fluorescence imaging of onion cells suggested the favorable cell membrane permeability of EC-T-PCBM and its prominent ability to continuously monitor the enrichment from Hg2+ within fresh plant tissues.

A novel ratiometric fluorescent sensor from modified coumarin-grafted cellulose for precise pH detection in strongly alkaline conditions.

Accurate and convenient monitoring of pH under extreme alkaline conditions is still a challenge. In this work, 4-(3-(7-hydroxy-2-oxo-2H-chromen-3-yl)-3-oxoprop-1-en-1-yl)benzamide (HCB), a coumarin derivative, was grafted onto dialdehyde cellulose (DAC) to obtain a sensor DAC-HCB, which exhibited a ratiometric fluorescent response to the pH of alkaline solutions, resulting in a significant fluorescent color change from yellow to blue (FI459 nm/FI577 nm) at pH 7.5-14. The structure of DAC-HCB was characterized through FT-IR, XRD, XPS, SEM. The pKa of sensor DAC-HCB was 13.16, and the fluorescent intensity ratio FI459 nm/FI577 nm possessed an excellent linear characteristic with pH in the scope of 9.0-13.0. Meanwhile, sensor DAC-HCB showed good selectivity, anti-interference, and fast response time to basic pH, which is an effective fluorescent sensor for examination of pH in alkali circumstance. The recognition mechanism of DAC-HCB to OH- was elucidated with HRMS and density-functional theory (DFT) computational analyses. Sensor DAC-HCB was successfully used for precise detection of environmental water samples pH. This work furnished a new protocol for test strips as a convenient and highly efficient pH detection tool for the high pH environment, and it has great potential for application in environmental monitoring.

Dopamine in the prefrontal cortex plays multiple roles in the executive function of patients with Parkinson's disease.

Parkinson's disease can affect not only motor functions but also cognitive abilities, leading to cognitive impairment. One common issue in Parkinson's disease with cognitive dysfunction is the difficulty in executive functioning. Executive functions help us plan, organize, and control our actions based on our goals. The brain area responsible for executive functions is called the prefrontal cortex. It acts as the command center for the brain, especially when it comes to regulating executive functions. The role of the prefrontal cortex in cognitive processes is influenced by a chemical messenger called dopamine. However, little is known about how dopamine affects the cognitive functions of patients with Parkinson's disease. In this article, the authors review the latest research on this topic. They start by looking at how the dopaminergic system, is altered in Parkinson's disease with executive dysfunction. Then, they explore how these changes in dopamine impact the synaptic structure, electrical activity, and connection components of the prefrontal cortex. The authors also summarize the relationship between Parkinson's disease and dopamine-related cognitive issues. This information may offer valuable insights and directions for further research and improvement in the clinical treatment of cognitive impairment in Parkinson's disease.

Xl019, a novel JAK inhibitor, suppressed osteoclasts differentiation induced by RANKL through MAPK signaling pathway.

Inbonemetabolism,osteoclastsare the only cellscapableofresorbingbone. Hyperactivity of osteoclasts may lead to osteolytic disease like osteoporosis and arthritis. Although there are several drugs for the treatment of osteolytic diseases, they have limitations and a variety of side effects. An inhibitor of Janus kinase (JAK), XL019, has shown promising results in the treatment of myelofibrosis and other cancers. But whether it can functionally impact osteoclast activity has not been proven. In this study, the effects of XL019 on osteoclastogenesis and the mechanism pathway were investigated in vitro. It was found that XL019 could impair osteoclasts formation, interfere with bone resorption ability and downregulate the osteoclast-specific genes and proteins expression. Furthermore, Western blot and molecular docking studies demonstrated that XL019 inhibited RANKL-induced osteoclastogenesis by suppressing MAPK signaling. A molecular docking analysis explained how XL019 binds to MAPK pathway factors. In addition, titanium particles induced calvarial osteolysis in mice further confirming its beneficial effect on bone homeostasis in vivo. In conclusion, this study demonstrates that Osteoclastactivity canbeeffectivelyinhibitedby XL019viaMAPK signalingpathway,making it a promising alternative pharmacologicaltreatmentfor bone metabolicdisorders.

Treadmill Exercise Alleviates Cognition Disorder by Activating the FNDC5: Dual Role of Integrin αV/ß5 in Parkinson's Disease.

Parkinson's disease with cognitive impairment (PD-CI) results in several clinical outcomes for which specific treatment is lacking. Although the pathogenesis of PD-CI has not yet been fully elucidated, it is related to neuronal plasticity decline in the hippocampus region. The dopaminergic projections from the substantia nigra to the hippocampus are critical in regulating hippocampal plasticity. Recently, aerobic exercise has been recognized as an effective therapeutic strategy for enhancing plasticity through the secretion of various muscle factors. The exact role of FNDC5-an upregulated, newly identified myokine produced after exercise-in mediating hippocampal plasticity and regional dopaminergic projections in PD-CI remains unclear. In this study, the effect of treadmill exercise on hippocampal synaptic plasticity was evaluated in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced chronic PD models. The results showed that treadmill exercise substantially alleviated the motor dysfunction, cognition disorder, and dopaminergic neuron degeneration induced by MPTP. Here, we discovered that the quadriceps, serum, and brain FNDC5 levels were lower in PD mice and that intervention with treadmill exercise restored FNDC5 levels. Moreover, treadmill exercise enhanced the synaptic plasticity of hippocampal pyramidal neurons via increased dopamine levels and BDNF in the PD mice. The direct protective effect of FNDC5 is achieved by promoting the secretion of BDNF in the hippocampal neurons via binding the integrin αVß5 receptor, thereby improving synaptic plasticity. Regarding the indirect protection effect, FNDC5 promotes the dopaminergic connection from the substantia nigra to the hippocampus by mediating the interaction between the integrin αVß5 of the hippocampal neurons and the CD90 molecules on the membrane of dopaminergic terminals. Our findings demonstrated that treadmill exercise could effectively alleviate cognitive disorders via the activation of the FNDC5-BDNF pathway and enhance the dopaminergic synaptic connection from SNpc to the hippocampus in the MPTP-induced chronic PD model.

HCEs-Net: Hepatic cystic echinococcosis classification ensemble model based on tree-structured Parzen estimator and snap-shot approach.

BACKGROUND: Hepatic cystic echinococcosis (HCE) still has a high misdiagnosis rate, and misdiagnosis may lead to wrong treatments seriously harmful for the patients. Precise diagnosis of HCE relies heavily on the experience of clinical experts with auxiliary diagnostic tools using medical images. PURPOSE: This paper intends to improve the diagnostic accuracy for HCE by employing a method which combines deep learning with ensemble method. METHODS: We proposed a method, namely HCEs-Net, for classification of five HCE subtypes using ultrasound images. It takes first the snap-shot strategy to obtain sub-models from the pre-trained VGG19, ResNet18, ViT-Base, and ConvNeXt-T models, then a stacking process to ensemble those sub-models. Afterwards, it uses the tree-structured Pazren estimator (TPE) to optimize the hyperparameters. The experiments were evaluated by the five-fold cross-validation process. RESULTS: A total of 3083 abdominal ultrasound images from 972 patients covering five subtypes of HCE were utilized in this study. The experiments were conducted to predict the HCE subtype, and results of modeling performance evaluation were reported in terms of precision, recall, F1-score, and AUC. The stacking model based on three ConvNeXt-T sub-models showed the best performance, with precision 85.9%, recall 85.5%, F1-score 85.7%, and AUC 0.971 which are higher than the compared state-of-the-art models. CONCLUSION: The stacking model of three ConvNeXt-T sub-models shows comparable or superior performance to the other methods, including VGG19, ResNet18 and ViT-Base. It has the potential to enhance clinical diagnosis for HCE.

Evaluation of NOx emissions before, during, and after the COVID-19 lockdowns in China: A comparison of meteorological normalization methods.

Meteorological normalization refers to the removal of meteorological effects on air pollutant concentrations for evaluating emission changes. There currently exist various meteorological normalization methods, yielding inconsistent results. This study aims to identify the state-of-the-art method of meteorological normalization for characterizing the spatiotemporal variation of NOx emissions caused by the COVID-19 pandemic in China. We obtained the hourly data of NO2 concentrations and meteorological conditions for 337 cities in China from January 1, 2019, to December 31, 2020. Three random-forest based meteorological normalization methods were compared, including (1) the method that only resamples meteorological variables, (2) the method that resamples meteorological and temporal variables, and (3) the method that does not need resampling, denoted as Resample-M, Resample-M&T, and Resample-None, respectively. The comparison results show that Resample-M&T considerably underestimated the emission reduction of NOx during the lockdowns, Resample-None generates widely fluctuating estimates that blur the emission recovery trend during work resumption, and Resample-M clearly delineates the emission changes over the entire period. Based on the Resample-M results, the maximum emission reduction occurred during January to February 2020, for most cities, with an average decrease of 19.1 ± 9.4% compared to 2019. During April of 2020 when work resumption initiated to the end of 2020, the emissions rapidly bounced back for most cities, with an average increase of 12.6 ± 15.8% relative to those during the strict lockdowns. Consequently, we recommend using Resample-M for meteorological normalization, and the normalized NO2 concentration dynamics for each city provide important implications for future emission reduction.

Modulation of broiler plasma metabolic spectrum by the addition of lysine residue to the diet.

Flavour is an important factor in evaluating meat quality, and amino acids and fats are important components affecting meat flavour. In this study, we evaluated the relationship between the variation of lysine residue addition and the slaughter performance and meat quality of broilers, which decreased with the addition of lysine residues but improved the meat quality of the broilers. 10% lysine residue addition was the most beneficial for reducing feed cost and improving meat quality. Meanwhile, the plasma metabolites of broilers fed increasing concentrations of lysine residue supplemented feeds were analysed using liquid chromatography-mass spectrometry (LC-MS). Principal component analysis (PCA) and partial least square discriminant analysis (OPLS-DA) were used screen, the differential metabolites induced by lysine residue. In the broilers 29, 37, 63, 87, 80 and 111 differential metabolites were detected (p < 0.05). Amongst them, 3-iodotyrosine, N-methyl-L-glutamic acid, coumaraldehyde, 2-dimethylphenol, N-methylnicotinamide and L-erythrone were the common differential metabolites between group A and groups B, C, D, E, F and G. The addition of lysine residue was positively correlated with alanine aminotransferase (p < 0.05, r = 0.942) and high-density lipoprotein cholesterol (p < 0.05, r = 0.798) and negatively correlated with aspartate aminotransferase (p < 0.05, r = 0.822). According to the classification of differential metabolites and their enriched pathway analysis, differential metabolites mainly caused changes in amino acid and lipid metabolism. Our study shows that a certain proportion of lysine residue in diet affects the specific metabolic pathway of broilers, which may affect amino acid and fat metabolism by regulating alanine aminotransferase, aspartate aminotransferase and high-density lipoprotein cholesterol, ultimately affecting the flavour.

Source profiles and reactivity of volatile organic compounds from anthropogenic sources of a megacity in southwest China.

Volatile organic compounds (VOCs) from anthropogenic sources are deleterious to air quality, climate, human health and vegetation. However, research on VOCs source profiles of the non-solvent use in some industries and the emission characteristics of motor vehicles under actual road conditions is limited in China. In this research, VOCs source profiles of industries (wood-based panel manufacturing and pharmacy) based on all product processes were constructed, and those of light and medium duty vehicles exhaust based on actual road conditions at different speeds were acquired in Chengdu, a megacity in southwest China. The results show that VOCs groups of various sources were dominated by oxygenated VOCs (OVOCs), which accounted for 27-84% of the total VOCs emission. Due to the great contribution of OVOCs to industrial source reactivity (SR), attention should be paid to the control over the emissions of the species with high reactivity, such as aromatics and alkenes, but also to the production processes with relatively large proportions of OVOCs species emission. VOCs emissions from gasoline and diesel vehicles running at a speed ranging from 0 to 40 km/h have approximately the same ozone formation potential (OFP), while the contribution of VOCs emission from diesel vehicles to the formation of urban ozone pollution deserves further attention. It is found that VOCs emission characteristics of some industries in China have changed as the upgrading of production processes in automobile manufacturing and other industries, such as the extensive use of water-based coatings instead of outdated solvent-based coatings, which increased the uncertainty of judgment parameters (B/T ratio, etc.) in source apportionment research. The ranges of B/T ratio of industrial process sources, solvent use sources and motor vehicles are 0.00-0.23, 0.01-0.75 and 0.35-0.92, respectively. Therefore, updating existing source profiles and further understanding the emission constitutions of characteristic species in these source profiles (such as BTEX ratio) will be conducive to further research on emission inventory, source apportionment for O3 pollution control effectively.

[Source Profiles of Industrial Emission-Based VOCs in Chengdu].

The volatile organic compound (VOC) emission characteristics of various production procedures were analyzed through GC-MS after the emissions of typical enterprises such as automobile manufacturing, petrochemical, and other industries had been sampled with SUMMA canisters. Each production procedure in the automobile manufacturing and petrochemical industries was considered. The results showed that each automobile manufacturing procedure had its own dominant species, and alkanes (32%) and aromatics (35%) were the main emission species of coating spraying. The emission characteristics of furniture manufacturing were highly correlated with the raw materials, and the VOC emission species were mainly composed of aromatics (50%) and oxygenated VOCs (OVOCs) (38%). As for the petrochemical industry, VOC concentrations in various process plant areas ranged from 49 µg·m-3 to 1387 µg·m-3. As the main products of the refining area were C5-C9 gasoline and benzene series, whereas comparatively more solvents were used in the chemical area, which would generate alkene products, VOC concentrations greatly differed in the various process plant areas. In terms of electronic manufacturing, OVOCs were the main emission species, accounting for more than 50% of total VOCs. Alkanes and OVOCs were the main contributors to VOC emissions in shoemaking, accounting for 52% and 36% on average, respectively, which was strongly related to the species of the used solvents. The VOC emission species of automobile manufacturing were quite different, predominantly including n-dodecane and 2-butanone. The emission species of furniture manufacturing mainly included styrene, ethyl acetate, m/p-xylene, etc., which are typical species of coatings and diluents. As for the differences in the emission species of process plant areas in the petrochemical industry, styrene was the main species in the refining area, 1,3-butadiene in the chemical area, C3-C5 alkanes in the storage area, and C6-C8 alkanes in the wastewater treatment area. The main emission species of electronic manufacturing were ethanol, acetone, and other aldehyde ketone species. The emission species of shoemaking enterprises are mainly C5 and C6 alkanes. According to the results of ozone formation potential (OFP), alkenes and aromatics were the main VOC emission species that contribute significantly to the OFP in the automobile manufacturing and petrochemical industries, with relatively high pollution source reaction activity. The results showed that the emission ratio (17%-96%) and OFP contributions of OVOCs were significant in various industries. Therefore, for VOC emission control, in addition to focusing on the control of aromatics and alkenes, attention should also be paid to OVOCs.

Correlation Analysis between AK1 mRNA Expression and Inosine Monophosphate Deposition in Jingyuan Chickens.

In this study, we examined correlations between the deposition of inosine monophosphate (IMP) and mRNA expression of the adenylate kinase 1 (AK1) gene in Jingyuan chicken. The IMP content was determined by high-performance liquid chromatography. Transcriptome sequencing was used to screen the differentially expressed gene AK1 and real-time quantitative polymerase chain reaction (PCR) to determine the expression level of AK1 mRNA associated with IMP synthesis. IMP and inosine content in the breast muscles of both Jingyuan cocks and hens was found to be significantly higher than that in the leg muscles. Similarly, the expression of AK1 mRNA in the breast muscles of cocks and hens was significantly higher than that in the leg muscles. Moreover, AK1 mRNA expression in cock breast muscles was negatively correlated with IMP content, whereas its expression in cock leg muscles was positively correlated with IMP content. In contrast, the expression of AK1 mRNA in hen breast and leg muscles was significantly positively correlated with IMP content. These findings provide a scientific basis for enhancing the meat flavor of Jingyuan chicken and promoting the development and utilization of local variety resources, as well as constituting a basis for screening IMP-regulated genes. Our study will advance our current understanding of AK1 function.

[Source Profiles of VOCs Associated with Typical Industrial Processes in Chengdu].

The characteristics of volatile organic compound (VOCs) species from various production procedures of wood-based panel production and other industrial processes in Chengdu were analyzed through gas chromatography-mass spectrometry (GC-MS) and other methods specified in national standards after the emissions of typical enterprises of wood-based panel production, pharmaceutical manufacturing, chemical production and other industrial processes in Chengdu had been sampled using sampling bottles and SUMMA canisters. Generally, the process of wood-based panel production includes glue making, glue mixing, sorting, and hot pressing, whereas the process of pharmaceutical manufacturing includes workshop production and wastewater treatment. The results showed that the main contribution species of VOCs in wood-based panel production and pharmaceutical manufacturing is oxygenated VOCs (OVOCs), accounting for more than 50% of the total VOCs emitted. The species from organized and unorganized emissions of formaldehyde manufacturing differed significantly. The main species of organized emissions was OVOCs, and that of unorganized emissions was halohydrocarbons. Emissions of VOCs from coating manufacturing were strongly correlated with the raw materials, and the corresponding emission species were composed mainly of aromatics and OVOCs. Except for glue mixing, the main species of VOCs in other process procedures of wood-based panel production was formaldehyde, with emission proportion of more than 50%. The primary species of VOCs in various processes of pharmaceutical manufacturing was ethanol; however 1,4-dioxane, ethyl acetate, and toluene were also important species. Moreover, the main VOCs from formaldehyde manufacturing were composed mainly of acetone and ethanol, and those of coating manufacturing were aromatic hydrocarbons such as p-xylene. The ozone formation potential was to characterize the reactivity of pollution sources in VOCs from wood-based panel production, pharmaceutical manufacturing, and chemical production. The results showed that the species of VOCs in different industries contributed similarly to the reactivity and that these species were mainly high-activity species such as formaldehyde, ethanol, and other OVOCs as well as some aromatic hydrocarbons. Therefore, supervision and regulation of enterprises of industrial processes is required with a focus on species with relatively large ozone formation potential. In addition, it is necessary to analyze the emission characteristics and chemical mechanism of various industries and to control O3 generation from the sources.

[Speciated VOCs Emission Inventory and Ozone Formation Potential in Sichuan Province].

Based on the measured data in the literature, VOCs (volatile organic compounds) source profiles were revised and reconstructed without OVOCs (oxygenated volatile organic compounds) species to obtain the normalized VOCs source profiles. Using the 2015 Sichuan emission inventory, source profiles based on the 1 km×1 km gridded speciated VOCs emission inventory were developed, and the ozone formation potentials of the species were estimated to assess the environmental impact on ozone formation. The established VOCs source profile database consists of 45 source profiles and 519 species. Since the source profiles were established based on the revision and reconstruction of pollution sources, such as biomass burning and transportation, that are rich in OVOCs, the source profile database is better applicable to establishing the speciated VOCs emission inventory and source apportionment. The speciated VOCs emission inventory showed that the total anthropogenic emission of VOCs in Sichuan Province was 773.8 kt, of which the emissions of alkanes, olefins, alkynes, aromatics, OVOCs, halohydrocarbons, and other VOCs accounted for 21.6%, 10.0%, 1.7%, 28.0%, 26.2%, 4.2%, and 8.3% of the total respectively. The total OFP (Ozone formation potential) was 2584.9 kt, of which the OFPs of the VOCs groups mentioned above accounted for 6.9%, 26.1%, 0.5%, 42.3%, 23.2%, 0.4%, and 0.5% respectively. The main VOCs species emitted in all cities of Sichuan Province were aromatics, OVOCs, and alkanes; however, there were some significant regional differences:transportation in Chengdu, Ya'an, Aba, Ganzi, and Liangshan made a greater contribution to VOCs emissions, with alkane emissions accounting for a higher proportion in the total VOCs emission. As a heavy industrial city, Panzhihua suffered most from emissions from industrial processes, which contain a relatively high proportion of alkanes. Solvent use in Deyang, Meishan, Suining, and Ziyang made a great contribution to the VOCs emissions, and the OVOCs emission was relatively high. Emissions of VOCs and species with relatively high OFPs in Sichuan Province were mainly distributed in the Sichuan Basin, which has a dense population and highly developed industry, as well as some areas in Liangshan and Panzhihua. The main source of m-xylene and toluene was solvent use; therefore, m-xylene and toluene were relatively concentrated in developed urban areas. In addition, biomass burning contributed greatly to the emissions of ethene and formaldehyde; therefore, ethene and formaldehyde were mainly distributed in the cultivated areas of agriculturally advanced Eastern Sichuan and Southern Sichuan.

Characterizing the composition and evolution of firework-related components in air aerosols during the Spring Festival.

To examine the impacts of fireworks, size-resolved PM samples were collected using a single-particle aerosol mass spectrometer before, during and after the Spring Festival in a megacity in Chengdu, China. Chemical composition and atmospheric behavior of urban particles were studied. Ten major single particle types were resolved with ART-2a algorithm including elemental and organic carbon (ECOC), EC, OC, levoglucosan (LEV), high molecular weight organic molecules (HOM), hard metal (HM), K rich, Na rich and SiO3-. The average OC/EC ratios decreased in the order AY (4.7) > overall (4.1) > NY (4.0) > BY period (3.6), indicating that many organic pollutants had been generated after the Spring Festival. The concentrations of many species exhibited an increasing trend during the firework period, and the SOR and NOR showed a strong increase in NY period. SOR and NOR had a slight positive relationship with fireworks activity but no obvious relationship with temperature.

[Emission Inventory and Characteristics of Anthropogenic Air Pollutant Sources in the Sichuan Province].

Based on anthropogenic source activity data and emission factors for the Sichuan Province, the 1 km×1 km-gridded atmospheric air pollutant emission inventory of 2015 was developed in combination with GIS technology and the combined "bottom-up" and "top-down" construction method. The results show that the total emission of SO2, NOx, CO, PM10, PM2.5, BC, OC, VOCs, and NH3 in Chengdu is 444.9×103, 820.0×103, 3773.1×103, 1371.6×103, 537.5×103, 28.7×103, 53.1×103, 923.6×103, and 988.0×103 t, respectively. Power plants and other industrial combustion boilers contribute more than 95% of the SO2 emissions. Mobile, fossil fuel combustion, and industrial process sources contribute 54%, 23%, and 20% of the NOx emissions, respectively. The industrial process of steel production and building materials manufacturing contribute 20% PM10 of the emissions and take up 34% PM2.5 of the emissions. Fugitive dust and road fugitive dust contributes 60% PM10 and 35% PM2.5 of the emissions, respectively. Biomass combustion contributes 33% BC and 51% OC of the emissions, respectively. The solvent use of mechanical processing, building decoration, electronic equipment manufacturing, and printing and furniture industry contribute 46% of the VOCs of the emissions. The NH3 emissions mainly orginate from the sources of livestock feeding and nitrogen fertilizers, accounting for 70% and 25% of the NH3 emissions, respectively. The spatial distribution of the emissions shows that high emissions are mainly distributed in the most densely populated, agricultural, and industrial more developed areas in Panzhihua and the Sichuan Basin. The urban agglomerations of the Chengdu Plain, represented by Chengdu, Deyang, and Mianyang, are the areas with emission concentration in the Sichuan Basin. The emissions inventory in this study has uncertainties. More fundamental studies on activity data should be conducted and the emission factors of typical emission sources should be further localized to improve the emission inventory and prevention and control of complex air pollution in the Sichuan Province and provide scientific support.

[X-Ray Fluorescence Intensity Calculation for Micro-Particles via MCNPX and WDXRF Experiment].

In order to research the effect of X-ray fluorescence (XRF) analysis on the results in the sample's micro particles, MCNPX models had been established for an X-ray fluorescence analyzer in this paper. It had studied the characteristics of the samples with different particle sizes, the fluorescence peak counts, the peak to total ratios and the peak to source ratios. A micro particle analysis experiment had been designed for its verification. The results showed that: as for the relationship between the fluorescence intensity and the particle sizes, the MCNPX calculations were consistent with the theoretical, but contrary with the experimental results; the reason is that some hypotheses about samples in the MCNPX models were contrary with the actual states; the samples were crushed by grinding to small particles and tableting process, the MCNPX calculations and experimental results can be conversion; when the particle sizes of the samples reached the certain sizes, the fluorescence peak counts, the peak to total ratios and the peak to source ratios were stable value; within a particular size range, the influence of the particle size effects cannot be ignored, otherwise this influence can be ignored. The research methods and conclusions in this paper can provide a technical reference guide for X-ray analysis in practices.