First-principles study of thermodynamic stability and mechanical properties of fifteen high-entropy quaternary metal disilicides.

By combining first-principles density-functional calculations and thermodynamics, we investigated the thermodynamic stability and mechanical properties of 15 quaternary high-entropy metal disilicides composed of silicon and four of the six refractory transition metals Ti, Zr, Hf, V, Nb, and Ta. We constructed a three-dimensional diagram specified by two thermodynamic parameters (the mixing enthalpy and the ratio of the entropy term in the Gibbs free energy to enthalpy) and a structural parameter (the lattice size difference). The obtained diagram allows us to predict that, except for TiZrHfVSi8, the formation of all other fourteen single-phase metal disilicides is thermodynamically favorable. Our calculations show that, for the formation of each of the 14 metal disilicides, the driving force suppresses the resistance at temperatures well below the melting point, suggesting that it is feasible to synthesize these high-entropy materials. One of these (TiHfNbTaSi8) has already been experimentally realized. Furthermore, the values of the mechanical parameters and melting points of the predicted fourteen quaternary high-entropy metal disilicides are all greater than the corresponding average values of the four single-metal disilicides.

Research progress on microbial control of sugarcane smut.

Sugarcane is the most important sugar crop. Sugarcane smut is one of the major diseases, which could reduce sugarcane yield and quality and seriously threaten the sustainable and healthy development of sugar industry. Microbial control of sugarcane smut is a rapidly emerging green biocontrol technology, with advantage to increase environmental compatibility and soil fertility. In this review, we briefly described the characteristics of Sporisorium scitamineum which causes sugarcane smut, synthesized the the mechanisms underlying the infection of sugarcane by S. scitamineum, and presented the research status of microbial controls of sugarcane smut via the application of bio-organic fertilizers and biopesticides. We then reviewed the mechanisms underlying the suppression of sugarcane smut by microorganisms through competition with pathogens for nutrients and ecological niches, secreting antagonistic substances, and improving plant resistance. It is notable that there are still some problems in the application of microbial control technologies, including poor colonization ability and unstable biocontrol efficiency. Finally, the major directions of future research on the biocontrol of sugarcane smut were proposed from the perspective of improving the biocontrol efficiency. This review would benefit the microbial control of sugarcane smut and the healthy development of sugar industry.

Incidence and risk factors of postoperative delirium after pancreatic cancer surgery: a retrospective study.

PURPOSE: Postoperative delirium (POD) commonly occurs after major abdominal surgery and is associated with increased morbidity and mortality. There have been many studies on the relationship between POD and various surgeries, but research on POD after pancreatic cancer surgery is limited. The aim of this study was to identify the incidence and risk factors of POD after pancreatic cancer surgery. METHODS: The subjects of this retrospective analysis were 196 patients who were transferred for postoperative care after pancreatic cancer surgery, to a 12-bed critical care medicine ward at Shandong Provincial Hospital, affiliated with Shandong First Medical University, between January 2015 and December 2019. The patients were divided according to whether they suffered POD into a delirium group and a non-delirium group. Delirium was assessed using the Confusion Assessment Method for the Intensive Care Unit and two independent medical practitioners analyzed all the data. Univariate and multiple logistic regression analyses were performed. RESULTS: The overall delirium incidence was 20.41%, which increased to 29.03% for patients aged ≥ 70 years. POD was associated with age, smoking, the American Society of Anesthesiologists classification, the Acute Physiology and Chronic Health Evaluation II score, and the TNM stage of the cancer. The variables concerning sex, drinking, hypertension, a history of cerebral disease, surgery type, operation time, amount of bleeding, and the intraoperative use of dexmedetomidine did not differ significantly between the two groups. There was no significant difference in the length of ICU stay, with the exclusion of long-term stay for complications, between the groups, but POD tended to prolong the postoperative hospital stay and increase the risk of mortality. There was also a gradual decline in the incidence of POD between 2015 and 2019, especially from 2015 to 2018, after preventive measures were implemented. CONCLUSION: POD is related to many risk factors and worthy of attention. Appropriate management can reduce its incidence or at least shorten its duration.

[Abundance of denitrifying genes and their driving factors in soil under different land use types in the karst region of Northwest Guangxi]. / æ¡‚è¥¿åŒ—å²©æº¶åŒºä¸åŒåœŸåœ°åˆ©ç”¨æ–¹å¼ä¸‹åœŸå£¤åç¡åŒ–åŸºå› ä¸°åº¦åŠå ¶é©±åŠ¨å› ç´ .

To understand the role of denitrifying microbes during vegetation recovery in karst regions, we determined the basic physicochemical properties and abundance of denitrifying microbial functional genes (nirS, nirK, fungal nirK, p450nor, and nosZ) of 13 collected soil samples under three land use types (cropland, grassland, and plantation) in Northwest Guangxi, and investigated the changes in the abundance of denitrifying microbial functional genes and their driving factors. Results showed that soil pH, soil organic carbon, total nitrogen (TN), and exchangeable calcium (Caexe) in plantation soil were significantly higher than those in cropland and grassland. The abundance of nirS, nirK, p450nor, and nosZ in plantation soil were significantly higher than those in cropland and grassland. Soil pH, TN, and Caexe were positively correlated with the abundance of denitrifying functional genes nirS, nirK, and p450nor. Results of redundancy analysis showed that soil Caexe, pH and TN were the primary factors influencing the abundance of denitrifying functional genes, which accounted for 34.1%, 20.1%, and 16.1% of the total variation, respectively. Such a result suggested that Caexe was the main driver of changes in denitrifying functional genes under different land use types. Overall, vegetation restoration (plantation) could effectively increase soil denitrifying microbe genes abundance in the karst region of Northwest Guangxi, and consequently influence soil nitrogen cycling.

Exposing Cu(100) Surface via Ion-Implantation-Induced Oxidization and Etching for Promoting Hydrogen Evolution Reaction.

Metallic materials with unique surface structure have attracted much attention due to their unique physical and chemical properties. However, it is hard to prepare bulk metallic materials with special crystal faces, especially at the nanoscale. Herein, we report an efficient method to adjust the surface structure of a Cu plate which combines ion implantation technology with the oxidation-etching process. The large number of vacancies generated by ion implantation induced the electrochemical oxidation of several atomic layers in depth; after chemical etching, the Cu(100) planes were exposed on the surface of the Cu plate. As a catalyst for acid hydrogen evolution reaction, the Cu plate with (100) planes merely needs 273 mV to deliver a current density of 10 mA/cm2 because the high-energy (100) surface has moderate hydrogen adsorption and desorption capability. This work provides an appealing strategy to engineer the surface structure of bulk metallic materials and improve their catalytic properties.

[Effects of Vegetation Restoration on Soil Nitrogen Pathways in a Karst Region of Southwest China].

Nitrogen (N) is an important element for plant growth in terrestrial ecosystems. Studying soil N cycling is crucial for understanding the structures and functions of an ecosystem. However, our knowledge of soil N dynamics in karst regions is still limited. In addition, while China's karst regions have conducted a series of vegetation restoration projects, the vegetation restoration effects on soil N pathways are still largely unknown. Therefore, this study selected four typical ecosystems representing four main vegetation restoration stages (i. e., cropland, grassland, shrubland, and forest) in a karst region in Huanjiang Province, southwest China. In these ecosystems, soil N pathways, including net ammonization rate (net ammonization, fungal ammonization, and bacterial ammonization), net nitrification rate (i. e., net nitrification, heterotrophic nitrification, autotrophic nitrification, fungal nitrification, and bacterial nitrification), net N mineralization rate (net N mineralization, fungal mineralization, and bacterial mineralization), and soil properties were measured. Our results showed that nitrification rate was high in all ecosystems, but the ammonization rate was low, resulting in nitrite being the main inorganic N form in karst soil. Autotrophic and heterotrophic nitrification rates accounted for 80% and 20% of the net nitrification rate, respectively. After the addition of fungal and bacterial inhibitors, ammonization rates increased for all treatments, but the nitrification rates decreased. Following vegetation restoration, soil N mineralization and nitrification rates all increased, but the ammonization rates significantly decreased. This pattern was significantly correlated with soil organic carbon, total nitrogen, nitrate, microbial biomass, and the activity of N-acquisition enzymes in these ecosystems. Our findings provide very useful information for understanding soil N cycling in the karst regions.

Compositional phase diagram and microscopic mechanism of Ba1-xCaxZryTi1-yO3 relaxor ferroelectrics.

With extensive first-principles density-functional calculations, we construct a three-dimensional compositional phase diagram of Ba1-xCaxZryTi1-yO3 (BCZT) with the Ca and Zr content in the ranges of 0 ≤ xCa ≤ 0.2 and 0 ≤ yZr ≤ 1. Our calculations show that, when the Zr content increases, the difference in energy and difference in the structural parameters of the cubic, tetragonal, orthorhombic, and rhombohedral phases of BCZT are reduced. Eventually, all four phases merge into a multiphase with coexisting cubic structures (MPCCS) under Zr-rich conditions, indicating that BCZT undergoes phase transition from a normal ferroelectric (NFE) to a relaxor ferroelectric (RFE), consistent with experimental observations. The 3D diagram shows that the regions of merged and separated energy surfaces correspond to the regions of the RFE and NFE, respectively, which suggests that a MPCCS corresponds to a RFE. In addition, with the MPCCS model and Landau-Devonshire theory, we provide an interpretation of the high electromechanical properties of the BCZT relaxor ferroelectric and apply it to the classical local random field and micro-macro domain transition models.

[Effects of Topography, Tree Species and Soil Properties on Soil Enzyme Activity in Karst Regions].

Soil extracellular enzymes are crucial in biogeochemical cycle and ecosystem functioning. Yet uncertainty exists in terms of major determinants on soil extracellular enzyme activity (EEA), especially at calcareous areas. In this study, soil samples (0-15 cm) were collected from different topographic conditions (different slope positions and aspects) and different tree species (Cryptocarya concinna and Eurycorymbus cavaleriei) in a forest located at Mulun natural reserve, a typical karst area. Six hydrolytic enzymes, related to carbon, nitrogen or phosphorus cycling, and soil physiochemical properties were investigated. The effects of topography, tree species and soil properties on soil enzyme activities were analyzed by multi-response permutation procedures (MRPP), redundancy analysis (RDA) and variation partitioning. The enzyme profiles were significantly (P<0.05) separated among the four slope positions but not significantly separated between the two aspects or two tree species according to multi-response permutation procedure (MRPP) analysis. Variation partitioning indicated that topography, tree species and soil properties together explained 55.3% of EEA variation. Soil property was the key factor influencing EEA variation, which explained 44.2% of EEA variation. The result of redundancy analysis (RDA) showed that soil pH, total nitrogen and inorganic nitrogen were the most important variables among the nine soil properties for EEA variation. This study first quantified the effects of small-scale topographic, tree species, and soil properties on soil enzyme activity variation in karst areas. Our results suggest that EEA variation can be well explained by soil properties at a small scale in the karst area.

Enhancement of interaction of L-929 cells with functionalized graphene via COOH+ ion implantation vs. chemical method.

Low hydrophilicity of graphene is one of the major obstacles for biomaterials application. To create some hydrophilic groups on graphene is addressed this issue. Herein, COOH+ ion implantation modified graphene (COOH+/graphene) and COOH functionalized graphene were designed by physical ion implantation and chemical methods, respectively. The structure and surface properties of COOH+/graphene and COOH functionalized graphene were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle measurement. Compared with graphene, COOH+/graphene and COOH functionalized graphene revealed improvement of cytocompatibility, including in vitro cell viability and morphology. More importantly, COOH+/graphene exhibited better improvement effects than functionalized graphene. For instance, COOH+/graphene with 1 × 1018 ions/cm2 showed the best cell-viability, proliferation and stretching. This study demonstrated that ion implantation can better improve the cytocompatibility of the graphene.

RUNX3 reverses cisplatin resistance in esophageal squamous cell carcinoma via suppression of the protein kinase B pathway.

BACKGROUND: Preoperative chemoradiation combined with surgery has been of focus recently in order to improve prognosis in esophageal squamous cell carcinoma (ESCC) patients. Finding biological markers that may assist in predicting the therapeutic effect of chemoradiation may benefit the treatment effect. In this study, the role of RUNX3 in the formation of cisplatin resistance in ESCC was examined. METHODS: The study enrolled 103 stage IIa-IIIb ESCC patients who had undergone esophagectomy. RUNX3 expression in ESCC tissue was detected. RESULTS: A higher expression of RUNX3 in ESCC patients correlated with a more sensitive response to cisplatin-based chemotherapy. A consistently lower expression of RUNX3 was found in the ESCC tissues of patients who agreed to perioperative chemotherapy compared with patients who had undergone no preoperative treatment. A lower RUNX3 expression in cisplatin-resistant ESCC cell lines, Eca109 and TE-1, was observed compared with parental cell lines. Heterologous RUNX3 expression significantly suppressed cisplatin resistance in Eca109 and TE-1, both in vitro and vivo. Meanwhile, heterologous RUNX3 expression could inhibit growth and induce apoptosis in cisplatin resistant Eca109 and TE-1 cell lines in vitro. Remarkable inhibition of the Akt pathway was observed in heterologous RUNX3 expression in Eca109 and TE-1. Silencing Akt1 could reverse cisplatin resistance in Eca109 and TE-1. CONCLUSION: Our results confirmed that a loss of RUNX3 in ESCC may contribute to cisplatin-resistance. RUNX3 could reverse cisplatin resistance via suppression of the Akt pathway in ESCC patients.

[The Interaction of Oil Microcapsule Wall Materials between Whey Protein and Acacia].

The interaction between whey protein and acacia which were used as wall material was studied on the formation of the oils microcapsules by the FTIR Spectroscopy and Computer Aided Analysis. The results indicated that whey protein changed obviously in amide A and amide I by high pressured homogenization and spray-drying. The amide A moved from 3 406.5 cm(-1) to 3 425.4 cm(-1) which was possibly due to covalent cross-linking between whey protein and acacia. Furthermore the amide I moved from 1 648.6 cm(-1) to 1 654.7 cm(-1) for intramolecular hydrogen bonding of protein had been weaken. After Gaussian fitting on amide I , it was found that the content of secondary structure of α-helix content and ß-folding in whey protein reduced from 19.55% to 17.50% and from 30.59% to 25.63%, respectively. This suggests that protein intramolecular hydrogen bonding force was abated, resulting in abating the rigid structure of the protein molecules and enhancing of the toughness structure. The protein molecules showed some flexibility. The result of SDS-PAGE electrophoresis showed that whey protein--gum Arabic complexes produced covalent products in larger molecular weight. During the spray-drying process, covalent cross-linking produced between whey protein and gum Arabic which improved emulsifying activity of the complex whey protein and gum Arabic produced covalent cross-linking and improved the complex emulsifying activity. Observing the surface structure of the fish oil microcapsule by SEM, the compound of whey protein and acacia as wall material was proved better toughness, less micropore, and more compact structure.

Physico-chemical properties of gelatin from bighead carp (Hypophthalmichthys nobilis) scales by ultrasound-assisted extraction.

In this study, gelatin was extracted from bighead carp (Hypophthalmichthys nobilis) scales by water bath (WB) and ultrasound bath (UB) at 60 °C for 1 h, 3 h and 5 h, named WB1, WB3, WB5, UB1, UB3 and UB5, respectively. The physicochemical properties of gelatin were investigated. The result indicated that gelatin extracted from bighead carp scales had a high protein content (84.15 ~ 91.85 %) with moisture (7.11 ~ 13.65 %), low ash content (0.31 ~ 0.97 %). All extracted gelatin contained α-and ß-chains as the predominant components. Gelatin extracted by UB obtained much higher yield (30.94-46.67 %) than that of WB (19.15-36.39 %). More voids and less sheets of gelatin structure were observed, when the gelatin was extracted by UB for longer time. Gelatin of UB-assisted extraction normally exhibited lower gel strength and melting points than that of WB, which may be resulted from the protein degradation reflected by the FTIR spectra and higher free amino group content. However, there was no significant difference between WB1 and UB1. Therefore, the ultrasound assisted extraction in a short time was a promising method to enhance the yield and obtain gelatin with high quality.

Ab initio atomistic thermodynamics study on the oxidation mechanism of binary and ternary alloy surfaces.

Utilizing a combination of ab initio density-functional theory and thermodynamics formalism, we have established the microscopic mechanisms for oxidation of the binary and ternary alloy surfaces and provided a clear explanation for the experimental results of the oxidation. We construct three-dimensional surface phase diagrams (SPDs) for oxygen adsorption on three different Nb-X(110) (X = Ti, Al or Si) binary alloy surfaces. On the basis of the obtained SPDs, we conclude a general microscopic mechanism for the thermodynamic oxidation, that is, under O-rich conditions, a uniform single-phase SPD (type I) and a nonuniform double-phase SPD (type II) correspond to the sustained complete selective oxidation and the non-sustained partial selective oxidation by adding the X element, respectively. Furthermore, by revealing the framework of thermodynamics for the oxidation mechanism of ternary alloys through the comparison of the surface energies of two separated binary alloys, we provide an understanding for the selective oxidation behavior of the Nb ternary alloy surfaces. Using these general microscopic mechanisms, one could predict the oxidation behavior of any binary and multi-component alloy surfaces based on thermodynamics considerations.

Gelatin quantification by oxygen-18 labeling and liquid chromatography-high-resolution mass spectrometry.

Combined with high-performance liquid chromatography (HPLC) and linear-ion trap/Orbitrap high-resolution mass spectrometry, trypsin-catalyzed (16)O-to-(18)O exchange was used to establish an accurate quantitative method for bovine or porcine gelatin. The sophisticated modifications for these two mammalian gelatins were unambiguously identified by accurate mass and tandem mass spectrometry. Eighteen marker peptides were successfully identified for the bovine and porcine gelatin, respectively. The gelatins were subjected to (18)O or (16)O labeling in the presence of trypsin and mixed together in various ratios for quantification. All of the (18)O-labeled peptides were also confirmed by accurate mass and tandem mass spectrometry. The 10 marker peptides with the strongest signals were chosen to calculate the average ratios of (18)O-labeled and (16)O-labeled gelatin. The measured ratios of (18)O-labeled and (16)O-labeled peptides were very close to the mixing ratios of 20:1, 5:1, 1:1, and 1:5 with low standard deviation values. The samples with a mixing ratio of 1:1 (18)O-labeled and (16)O-labeled peptides were determined to 1.00 and 0.99 with standard deviations of 0.02 and 0.04 for bovine and porcine gelatins, respectively, indicating the high accuracy of this method. Trypsin-catalyzed (18)O labeling was proved to be an excellent internal calibrant for gelatins. When combined with HPLC and high-resolution mass spectrometry, it is an accurate and sensitive quantitative method for gelatin in the food industry.

High current density and longtime stable field electron transfer from large-area densely arrayed graphene nanosheet-carbon nanotube hybrids.

Achieving high current and longtime stable field emission from large area (larger than 1 mm(2)), densely arrayed emitters is of great importance in applications for vacuum electron sources. We report here the preparation of graphene nanosheet-carbon nanotube (GNS-CNT) hybrids by following a process of iron ion prebombardment on Si wafers, catalyst-free growth of GNSs on CNTs, and high-temperature annealing. Structural observations indicate that the iron ion prebombardment influences the growth of CNTs quite limitedly, and the self-assembled GNSs sparsely distributed on the tips of CNTs with their sharp edges unfolded outside. The field emission study indicates that the maximum emission current density (Jmax) is gradually promoted after these treatments, and the composition with GNSs is helpful for decreasing the operation fields of CNTs. An optimal Jmax up to 85.10 mA/cm(2) is achieved from a 4.65 mm(2) GNS-CNT sample, far larger than 7.41 mA/cm(2) for the as-grown CNTs. This great increase of Jmax is ascribed to the reinforced adhesion of GNS-CNT hybrids to substrates. We propose a rough calculation and find that this adhesion is promoted by 7.37 times after the three-step processing. We consider that both the ion prebombardment produced rough surface and the wrapping of CNT foot by catalyst residuals during thermal processing are responsible for this enhanced adhesion. Furthermore, the three-step prepared GNS-CNT hybrids present excellent field emission stability at high emission current densities (larger than 20 mA/cm(2)) after being perfectly aged.

Quantum breathers in Heisenberg ferromagnetic chains with Dzyaloshinsky-Moriya interaction.

We present an analytical study on quantum breathers in one-dimensional ferromagnetic XXZ chains with Dzyaloshinsky-Moriya interaction by means of the time-dependent Hartree approximation and the semidiscrete multiple-scale method. The stationary localized single-boson wave functions are obtained and these analytical solutions are checked by numerical simulations. With such stationary localized single-boson wave functions, we construct quantum breather states. Furthermore, the role of the Dzyaloshinsky-Moriya interaction is discussed.

Irradiation damage determined field emission of ion irradiated carbon nanotubes.

Figuring out the underlying relationship between the field emission (FE) properties and the ion irradiation induced structural change of carbon nanotubes (CNTs) is of great importance in developing high-performance field emitters. We report here the FE properties of Si and C ion irradiated CNTs with different irradiation doses. It is found that the FE performance of the ion irradiated CNTs ameliorates before and deteriorates after an irradiation-ion-species related dose. The improved FE properties are ascribed to the increased amount of defects, while the degraded FE performance is attributed to the great shape change of CNTs. These two structural changes are further characterized by a structural damage related parameter: dpa (displacement per atom), and the FE performance of the ion irradiated CNTs is surprisingly found to be mainly dependent on the dpa. The optimal dpa for FE of the ion irradiated CNTs is ∼0.60. We ascribe this to the low irradiation doses and the low substrate temperature that make the ion irradiation play a more important role in producing defects rather than element doping. Furthermore, the ion irradiated CNTs exhibit excellent FE stability, showing promising prospects in practical applications.

Self-assembled growth of multi-layer graphene on planar and nano-structured substrates and its field emission properties.

Vertical multi-layer graphenes (MLGs) have been synthesized without a catalyst on planar and nano-structured substrates by using microwave plasma enhanced chemical vapor deposition. The growth of MLGs on non-carbon substrates is quite different from that on carbon-based substrates. It starts with a pre-deposition of a carbon buffer layer to achieve a homo-epitaxial growth. The nucleation and growth of MLGs was found to be strongly influenced by the surface geometry and topography of substrates. Planar substrates suitable for atom diffusion are favorable for growing large-scale MLGs, and defect-rich substrates are beneficial for quick MLG nucleation and thus the growth of densely distributed MLGs. The field emission properties of MLGs grown on planar and nano-structured substrates were studied and are found to be strongly dependent on the nature of substrates. Substrates having good conductivity and large aspect ratios such as carbon nanotubes (CNTs) have good field emission properties. The best field emission properties of MLG/CNT composites with optimal shapes were observed with a low turn-on electric field of 0.93 V µm(-1), a threshold field of 1.56 V µm(-1), a maximum emission current density of 60.72 mA cm(-2), and excellent stability.

Synthesis of 4-methylcoumarin derivatives containing 4,5-dihydropyrazole moiety to scavenge radicals and to protect DNA.

A series of 4-methylcoumarin derivatives containing 4,5-dihydropyrazole moiety were synthesized and their antioxidant activities were evaluated in AAPH (2,2'-azobis(2-amidinopropane hydrochloride))-induced oxidation of DNA, and in trapping DPPH (2,2'-diphenyl-1-picrylhydrazyl) and ABTS(+•) (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical), respectively. Among coumarin derivatives, 3a-d and 4a-c exhibited the termination of radical propagation-chains in AAPH-induced oxidation of DNA. The ortho dihydroxyphenyl substitution at 5 position and 1-unsubstitution of the 4,5-dihydroxylpyrazole was found enhancing the antioxidant activities of these coumarin derivatives.

Dynamic neural responses to cue-reactivity paradigms in heroin-dependent users: an fMRI study.

Neuroimaging methods have been employed to study cue-reactivity-induced neural correlates in the human brain. However, very few studies have focused on characterizing the dynamic neural responses to the factorial interactions between the cues and the subjects. Fifteen right-handed heroin-dependent subjects and 12 age-matched nondrug using subjects participated in this study. Cue-reactivity paradigms were employed, while changes in blood oxygenation level-dependent (BOLD) signals were acquired by functional MRI (fMRI). The fMRI datasets were analyzed with AFNI software and repeated two-way ANOVA was employed for factorial analyses. Neural correlates of factorial interactions between cue-factor and subject-factor were identified in the regions of the ventral tegmental area (VTA), the left and right amygdala, the left and right fusiform cortex, and the precuneus in the mesocorticolimbic system, and in the superior frontal, dorsal lateral prefrontal, and orbitofrontal cortices in the prefrontal cortex system. The neural response patterns in the prefrontal systems are dynamic: decreased response to neutral-cues and increased response to heroin-cues. Further, heroin-cue-induced neural responses within the subregions in the PFC system are significantly intercorrelated. In conclusion, the cue-reactivity paradigms significantly activated the dynamic neural activations in the prefrontal system. It is suggested that the dynamic response patterns in the PFC system characterize the impaired brain control functions in heroin-dependent subjects.