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Abnormal polarization of adipose tissue macrophages (ATMs) results in low-grade systemic inflammation and insulin resistance (IR), potentially contributing to the development of diabetes. However, the underlying mechanisms that regulate the polarization of ATMs associated with gestational diabetes mellitus (GDM) remain unclear. Thus, we aimed to determine the effects of abnormal fatty acids on macrophage polarization and development of insulin resistance in GDM. Levels of fatty acids and inflammation were assessed in the serum samples and adipose tissues of patients with GDM. An in vitro cell model treated with palmitic acid was established, and the mechanisms of palmitic acid in regulating macrophage polarization was clarified. The effects of excessive palmitic acid on the regulation of histone methylations and IR were also explored in the high-fat diet induced GDM mice model. We found that pregnancies with GDM were associated with increased levels of serum fatty acids, and inflammation and IR in adipose tissues. Increased palmitic acid could induce mitochondrial dysfunction and excessive ROS levels in macrophages, leading to abnormal cytoplasmic and nuclear metabolism of succinate and α-ketoglutarate (αKG). Specifically, a decreased nuclear αKG/succinate ratio could attenuate the enrichment of H3K27me3 at the promoters of pro-inflammatory cytokines, such as IL-1β, IL-6, and TNF -α , leading to cytokine secretion. Importantly, GDM mice treated with GSK-J4, an inhibitor of histone lysine demethylase, were protected from abnormal pro-inflammatory macrophage polarization and excessive production of pro-inflammatory cytokines. Our findings highlight the importance of the metabolism of αKG and succinate as transcriptional modulators in regulating the polarization of ATMs and the insulin sensitivity of adipose tissue, ensuring a normal pregnancy. This novel insight sheds new light on gestational fatty acid metabolism and epigenetic alterations associated with GDM. Schematic illustration showing how abnormal FFA concentrations regulate M1 type macrophage polarization and insulin resistance in GDM. In women with GDM, the levels of FFAs are elevated. These elevated FFAs can be absorbed by monocytes, leading to mitochondrial dysfunction and a decreased ratio of αKG/succinate. The decreased αKG/succinate ratio results in a lower enrichment of H3K27me3 in the promoter of pro-inflammatory cytokines, leading to M1 type macrophage polarization and insulin resistance in adipose tissues. Thus, elevated FFAs in GDM might induce adipose tissue insulin resistance by promoting macrophage polarization by influencing αKG/succinate metabolism and H3K27me3 modification. [Display omitted] • Pregnancies with GDM are associated with increased levels of serum fatty acid. • Excess PA disturbs macrophage αKG/succinate metabolism and promoters' enrichment of H3K27me3 at pro-inflammatory cytokines. • GDM mice induced by a high-fat diet treated with the GSK-J4 inhibitor partially restore insulin sensitivity. [ABSTRACT FROM AUTHOR]

The incorporation of phase change material (PCM) into building structures offers a pathway for passive energy storage, enabling adaptable indoor temperature control and alleviating energy consumption. Despite these advantages, the widespread adoption of PCM in building structures faces challenges due to extended payback periods. In this study, a novel and cost-effective salt hydrate PCM composite, comprised of calcium chloride hexahydrate–potassium chloride (CCH–KCl), was developed. Melamine foam (MF) and strontium chloride hexahydrate (SCH) were synergistically utilized to address phase separation and supercooling issues. Numerical simulations were conducted to assess the performance of the developed salt hydrate PCM composite in building partition walls. Specifically, incorporating a 20 mm-thick composite resulted in peak temperature reductions of 0.72 °C during normal operation and 1.01 °C during power outages compared to structures without PCM, accompanied by a substantial reduction in energy consumption by 5376.68 kWh/year. Moreover, the cost of the developed salt hydrate PCM is 89.33 % lower than industrial paraffin, and it reduces CO2 emissions by 1.40 kg/year/m2 compared to paraffin's 1.11 kg/year/m2. In summary, the developed salt hydrate PCM composite exhibits commendable thermal regulation and economic advantages in building applications, serving as a pivotal contributor to emission reduction efforts. [Display omitted] • Phase separation and supercooling issues of salt hydrate PCM were addressed. • Melting temperature of salt hydrate PCM was tailored for passive solar buildings. • Thermo-regulated performance of the salt hydrate PCM was evaluated. • The cost of the developed PCM is 89.33 % lower than that of industrial paraffin. [ABSTRACT FROM AUTHOR]

In the preparation of plasma electrolytic oxidation (PEO) coating, the rapid heating of freely-happened electron avalanche under traditional discharge (TD) mode inevitably results in a strong eruption of electric breakdown melt. The PEO coating is loose and invariably composed of a very thin inner dense layer and an outer loose layer, as a result of which its properties and application have been limited greatly. In this work, for purpose of weakening the eruption of breakdown melt, thickening the inner dense layer, densifying the outer loose layer and improving the performance of PEO coating, ordinal discharge (OD) mode of PEO coating is developed by regulating the mass ratio of MgF 2 to MgO (α) and voltage in the PEO investigation on AZ61 magnesium alloy in KF-KOH electrolyte. The formation mechanism under different discharge mode, electrochemical corrosion and wear of PEO coatings are investigated. The results show that the suitable α and voltage for effective OD are 1.3 and 130 V under which the freely-happened electron avalanche in MgF 2 under TD mode can be restricted by the adequate adjacent MgO. Compared with TD mode, the inner dense layer, in which the (1 ¯ 0 1 ¯) plane of MgF 2 is parallel to the (111) plane of MgO at their well-knit semi-coherent interface, is thickened to 2.4∼7.2 times, the corrosion potential (E corr) improvement is enlarged to 3.6∼13.2 times and the corrosion current intensity (I corr) is reduced from 10.8∼9.499 to 0.433 (10−6 A/cm2). The outer loose layer is densified and the wear rate is lessened 65.5%∼89.8% by the evident melioration in surface porosity, impedance and hardness. This work deepens the understanding about the discharge of PEO coating and provides an available OD mode for preparing excellent PEO coating. [ABSTRACT FROM AUTHOR]

The unsaturated vegetable oil is commonly incorporated as protein-stabilized emulsion into fat-substituted emulsified meat products (FSEMP), whose quality is closely related with the emulsion stability. Here, we systematically investigated the effects of oil unsaturation degree (UD) on the interfacial properties (structural changes, adsorption dynamics, interfacial rheology, adsorption layer thickness) of proteins and thus the emulsion stability. The oleic acid and linolenic acid were mixed with dodecane as model oils. Three types of proteins were selected as model emulsifiers (fibrous myofibrillar protein, MP; globular whey protein, WP; random-coiled sodium caseinate, SC). The proteins diffused slower to the higher UD interface, resulting in a lower interfacial pressure. This led to a larger droplet size of the higher UD oil emulsion upon emulsification. However, the proteins penetrated and rearranged faster at the higher UD interface ascribed to a more extensive structural unfolding, enabling the formation of stiffer and thicker adsorption layers. This contributed to a stronger short-term stability of MP- and WP-stabilized higher UD oil emulsion; while for the random-coiled SC, the higher UD oil emulsion was less short-term stable, which was primarily determined by the initial (larger) droplet size but not the interfacial layer properties. The stiffer layer at the higher UD interface was on the other hand less stretchable, which tended to yield when subjected to higher strain. This probably accounted for the weaker long-term stability of the higher UD oil emulsion, regardless of protein types. These results highlighted that the oil UD should be elaborately considered for the rational formulation of FSEMP. [Display omitted] • Proteins suffered greater unfolding at the higher unsaturation degree (UD) interface. • Proteins diffused slower but penetrated and rearranged faster at higher UD interface. • Proteins formed stiffer, thicker but brittler layers at higher UD interface. • The higher UD oil emulsion was larger in the initial droplet size. • The higher UD oil emulsion was more short-term stable but less long-term stable. [ABSTRACT FROM AUTHOR]

[Display omitted] • Myofibrillar protein-luteolin vehicle was greenly prepared with a high load capacity. • The differences between ethanol and non-ethanol samples were compared. • Ethanol samples showed superior in vitro antioxidant capacity. • Non-ethanol samples showed superior sustained-release properties. In this study, the highly loaded myofibrillar protein (MP)-luteolin (Lut) complexes were noncovalently constructed by using green high-pressure homogenization technology (HPH) and high-pressure micro-fluidization technology (HPM), aiming to optimize the encapsulation efficiency of flavonoids in the protein-based vehicle without relying on the organic solvent (i.e. DMSO, ethanol, etc.). The loading efficiency of Lut into MPs could reach 100 % with a concentration of 120 μmol/g protein by using HPH (103 MPa, 2 passes) without ethanol adoption. The in vitro gastrointestinal digestion behavior and antioxidant activity of the complexes were then compared with those of ethanol-assisted groups. During gastrointestinal digestion, the MP digestibility of complexes, reaching more than 70.56 % after thermal treatment, was higher than that of sole protein. The release profile of Lut encapsulated in ethanol-containing and ethanol-free samples both well fitted with the Hixson-Crowell release kinetic model (R2 = 0.92 and 0.94, respectively), and the total phenol content decreased by ≥ 40.02 % and ≥ 62.62 %, respectively. The in vitro antioxidant activity (DPPH, ABTS, and Fe2+) of the digestive products was significantly improved by 23.89 %, 159.69 %, 351.12 % (ethanol groups) and 13.43 %, 125.48 %, 213.95 % (non-ethanol groups). The 3 mg/mL freeze-dried digesta significantly alleviated lipid accumulation and oxidative stress in HepG2 cells. The triglycerides and malondialdehyde contents decreased by at least 57.62 % and 67.74 % after digesta treatment. This study provides an easily approached and environment-friendly strategy to construct a highly loaded protein–flavonoid conjugate, which showed great potential in the formulation of healthier meat products. [ABSTRACT FROM AUTHOR]

The inadvertent flow of mildly/moderately oxidized oil into production critically causes quality uncontrollability in food emulsions. In this paper, we explored the effects of oil pre-oxidation (oxidized before emulsification) on the emulsion stability and interfacial properties of two protein emulsifiers (myofibrillar protein, MP; sodium caseinate, SC). These effects were further found to be different dependent on the proteins native structural and physicochemical properties. For MP with a highly structured fibrous conformation, the adsorption capacity, diffusion and rearrangement rate, and dilatational elastic modulus were decreased (by at least 5.74%, 16.25%, 11.21%, 10.04% respectively) at the oxidized-oil/water interface, which were mainly explained by the increased oil polarity and the generated interfacial-active oxidation products that impeded the interfacial unfolding and protein-protein interactions. With an appreciably high adsorbed amount (adsorption ratio >90%), the MP's oxidized-oil emulsion stability was largely determined by the interfacial properties, and thus significantly decreased with oil oxidation (even at the mild oxidation level). In contrast, for SC with a disordered structure, the rearrangement rate and dilatational elastic modulus were similarly decreased (by at least 14.61%, 12.56% respectively) at the oxidized-oil/water interface, while the adsorption capacity and diffusion rate were increased (by at least 5.40%, 13.16% respectively) possibly due to the enhanced hydrogen bonding between the more hydrophilic SC and the higher polarity oil. With a significantly lower adsorbed amount (adsorption ratio <10%), the SC's oxidized-oil emulsion stability was mainly decided by the oil inherent properties but not interfacial performance, which thus significantly increased with oil oxidation (even at the mild level) due to the growing oil polarity and density. These findings highlight that mild oil pre-oxidation could have critical impacts on emulsion stability, and the mechanism exploration provides scientific guidelines for the quality control and rational formulation of labile unsaturated oil-based emulsion foods (e.g. fat substituted emulsified meat products). [Display omitted] • Oxidation increased oil polarity with the generation of interfacial-active products. • Oil pre-oxidation impaired MP emulsion stability but promoted SC emulsion stability. • Oil pre-oxidation impaired rearrangement rate, interfacial film strength of MP and SC. • Adsorption capacity and diffusion rate varied depended on protein properties. • Dispersed-phase and interfacial-film both mattered in affecting emulsion stability. [ABSTRACT FROM AUTHOR]

• The Widom lines of four thermodynamic properties of CO2/natural gas mixtures were calculated to study the characteristics of supercritical mixtures at near critical points. • A new Widom line vanishing point criterion based on the coefficient of variation was proposed with a moderate range, clear statistical significance, and a better economy for industrial applications. • Results show that the influence of CO2 concentration on the characteristic of "thermodynamic fluctuations" of the mixture does not increase uniformly, but is positively correlated with concentration. It can be considered that mixtures with xCO 2 = 0 ∼ 0.6 exhibit weak fluctuations. • Results show that different equipment need to avoid different Widom lines and maintain a safe temperature margin about 20 ∼ 30 K. The Widom lines of mixture indicate the abnormal response behavior of properties of mixed supercritical fluid near the critical point, determining operating conditions in supercritical region of ground equipment in CCUS. Peng-Robinson equation (PR-EOS) is used to calculate Widom lines of isothermal compressibility coefficient, isobaric expansion coefficient, isobaric specific heat, and density of CO 2 /natural gas quinary mixture. A new criterion is proposed to calculate the vanishing points of Widom lines using the coefficient of variation (CV) of response function distribution, with a clear statistical meaning and an appropriate range, compared with existing criteria. Based on the new criterion, the effect of CO 2 concentration on the thermodynamic fluctuations in the near-critical region of CO 2 /natural gas mixture is analyzed. It is found that thermodynamic fluctuations of mixture are controlled by CO 2 concentration and fluctuations can be considered relatively weak when CO 2 concentration is below 60 %. The selection and control of operating conditions of pipeline and compressor unit in CCUS application are discussed to cope with the Widom region movement caused by changes in CO 2 concentration. [ABSTRACT FROM AUTHOR]

The effects of the oils density and viscosity (DV) on the emulsions kinetic stability and destabilization mechanisms were revealed from the perspective of droplets movement and emulsions viscosity. With the extension of storage time, severe creaming (20.20 ± 0.73 × 10−4 mm/s), flocculation and coalescence (7.26 ± 0.82 μm−2 min−1) occurred in emulsions prepared with oils of lowest DV; the extent of creaming (15.90 ± 0.68 × 10−4 mm/s) and coalescence (1.36 ± 0.10 μm−2 min−1) were alleviated upon increasing oils DV, accompanied by the occurrence of acute Ostwald ripening (17.03 ± 1.72 μm3 min−1); and only slight creaming (2.26 ± 0.24 × 10−4 mm/s), flocculation, coalescence (0.70 ± 0.09 μm−2 min−1) and Ostwald ripening (6.14 ± 0.42 μm3 min−1) occurred in emulsions prepared with oils of highest DV. This was because oils with higher DV (especially density) restricted the droplets fluidity due to an increased motion friction, leading to a more homogeneous internal network and a higher apparent/macroscopic viscosity (0.31 ± 0.04 Pa·sn and 0.1 nm−2 s) of emulsions. These impeded the Brownian motion and diffusion of droplets to decrease the collision frequency/efficiency and mass transfer respectively, which in turn conduced to retarding droplets size enlargement and stabilizing the emulsions against different destabilization mechanisms. [Display omitted] • Higher oil density and viscosity (DV) improves emulsions stability. • Oils of high DV increase the emulsion viscosity. • Oils of high DV retard gravitational separation to increase creaming stability. • Oils of high DV delay Brownian motion to increase flocculation/coalescence stability. • Density plays a more decisive role in tuning emulsions viscosity and stability. [ABSTRACT FROM AUTHOR]

In this paper, we study the following quasilinear chemotaxis model with singular sensitivity and indirect signal production (0.1) u t = ∇ ⋅ (D (u) ∇ u) − χ ∇ ⋅ (u v k ∇ v) + u (a − b u) , t > 0 , x ∈ Ω , v t = Δ v − v + w , t > 0 , x ∈ Ω , w t = Δ w − w + u , t > 0 , x ∈ Ω , under homogeneous Neumann boundary conditions in a convex smooth bounded domain Ω ⊂ R N , N ≥ 3 , where, χ , a , b > 0 , k ∈ (0 , 1 2) ∪ (1 2 , 1 ] and D (u) is smooth function satisfying D (u) ≥ (u + 1) α with α > 0. By constructing suitable Lyapunov functional, we prove that if a > χ 2 4 , there exists a positive constant m ∗ such that ∫ Ω u ≥ m ∗. Based on above result, the lower bound estimates for w and v have been established. When b is large enough and α > max { 0 , 1 − 4 N } , we further prove that the system has a global bounded classical solution. Finally, it is shown that the solution exponentially converges to the constant stationary solution (a b , a b , a b) as t → ∞. [ABSTRACT FROM AUTHOR]

Antibiotics and heavy metals added to livestock and poultry feed are excreted in manure, which is added to agricultural soil and causes severe pollution. However, the effects of oxytetracycline (OTC) and zinc (Zn), which are present at relatively high levels in feed additives, on antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), and microbial communities have not been comprehensively studied. This study evaluated the effects of OTC and Zn on environmental factors, microorganisms, MGEs, and ARGs. The expression of MGEs in soil was stimulated by adding Zn at concentrations of 500 and 1000 mg/kg or OTC at concentrations of 30 and 100 mg/kg; however, the addition of their combination hindered the expression of MGEs in soil. The abundance of total MGEs and ARGs tended to decrease with increasing concentrations of Zn and OTC and the number of incubation days. Low and high OTC concentrations strongly inhibited sul and tet resistance genes, respectively. Network analysis showed that changes in the population of Firmicutes and Proteobacteria had the greatest impact on ARG abundance. Redundancy analysis revealed that MGEs, particularly intI2 , facilitated the transfer and spread of ARGs and had the greatest impact on changes in ARG abundance. These findings provide reference values for the prevention and resolution of ecological and environmental risks posed by the presence of Zn and OTC in organic manure soil. [Display omitted] • Zn and OTC contamination alone promoted the expression of MGEs (intI1 and intI2). • ARGs expression was reduced by contamination with high Zn and OTC concentrations. • Firmicutes and Proteobacteria are the main potential host bacteria of ARGs. • MGEs (especially intI2) play a key role in the expression and propagation of ARGs. [ABSTRACT FROM AUTHOR]

Myofibrillar protein (MP) majorly determines the quality of emulsified meat product. Since MP is sensitive to external stresses, it would easily denature and form aggregates during processing. However, for now, how MP aggregates size affects its emulsion properties is still lacking clarification. In this study, large/small-sized MP aggregate-models with similar structural properties were successfully established through pH-shifting treatment. Specifically, the NaOH–HCl/gluconolactone induced MP aggregates were treated as large aggregate (LA) and small aggregate (SA) models, respectively, which were subsequently validated through transmission electron microscopy (sectional size: LA 282.47 nm2 and SA 104.79 nm2), gel-permeation chromatography (aggregate peak proportion: LA 73.75% and SA 66.86%) and dynamic light scattering (mean volume weight diameter: LA 45.33 μm and SA 26.20 μm). Then, the structural properties were measured to confirm the equivalent conformation for both models, which exhibited similar protein profiles and molecular flexibility values, and same changing trend in the secondary structure as well as protein unfolding level. Under similar spatial conformation, aggregate size could be the dominant factor to determine interfacial behaviors and emulsifying properties of protein aggregate. Smaller aggregates of SA may be beneficial for the higher interfacial diffusion and rearrangement rate, and greater ability to reduce interfacial tension compared with those of LA. Therefore, SA had better emulsion properties than LA with higher emulsifying activity and stability, and lower Turbiscan stability index. These aggregate models have implications for the development of healthy emulsified meat products, which is conducive to more precise control of product quality and sensory. [Display omitted] • The large/small-sized MP aggregates were prepared using HCl/GDL during pH-shifting. • Different sized-aggregate rendered similar spatial conformation. • SA had highest ability to reduce interfacial tension and fastest K diff and K r values. • Mild size aggregates may improve the emulsion properties and interfacial behaviors. [ABSTRACT FROM AUTHOR]

Abstract Water-soluble prodrugs of propofol often carry an excess of propofol at the effective dose and have a slower onset of action. Sustained release of the original drug can result in propofol accumulation in the body after administration, causing delays in wakefulness. This situation causes the prodrug to lose the benefits of rapid onset and recovery from the effects of propofol. In the present study, HX0921 (sodium 2-(2-(2,6-diisopropylphenoxy)-2-oxoethoxy)acetate), an improved prodrug of propofol with high utilization of propofol and fast onset of action, was studied. The rate of propofol release from HX0921 was much faster than that from fospropofol (a marketed propofol prodrug) in rat plasma. The 50% effective dose (ED 50) of propofol, HX0921 and fospropofol to induce anesthesia in rats was 5.78, 22.19 and 42.44 mg/kg, respectively. After administration at 2 × ED 50 , the onset time of anesthesia in the HX0921 group was significantly shorter than that in the fospropofol group (0.26 ± 0.15 min vs. 2.24 ± 0.35 min, P < 0.01) and the duration of anesthesia in the HX0921 group was also significantly shorter than that in the fospropofol group (22.35 ± 4.05 min vs. 29.15 ± 5.25 min, P < 0.01). These results suggest that the rapid onset and short action time of HX0921 was due to the rapid release and high molecular utilization of propofol carried by HX0921. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Novel antimycin alkaloid antimycin A2c (AE) was isolated from the culture of a marine derived Streptomyces sp. THS-55. We elucidated its chemical structure by extensive spectra and clarified the specific mechanism in HPV infected-cervical cancer. Colony formation assay, cell cycle analysis, hoechst 33342 staining assay, et.al were used to detect the inhibitory effect of AE on cervical cancer cells. Meanwhile, flow cytometry, western blotting, immunoprecipitation, RNA interference and molecular docking were used to analyze the mechanism of AE. AE exhibited potent cytotoxicity in vitro against HPV-transformed cervical cancer HeLa cell line. AE inhibited the proliferation, arrested cell cycle distribution, and triggered caspase dependent apoptosis in HeLa cells. Further studies revealed AE-induced apoptosis is mediated by the degradation of E6/E7 oncoproteins. Molecular mechanic investigation showed that AE degraded the levels of E6/E7 oncoproteins through reactive oxygen (ROS)-mediated ubiquitin-dependent proteasome system activation, and the increased ROS generation was due to the disruption of the mitochondrial function. This present work revealed that this novel marine derived antimycin alkaloid could target the mitochondria and subsequently degrade HPV E6/E7 oncoproteins, and have potential application in the design and development of lead compound for cervical cancer cells, as well as the development for tool compounds to dissect E6/E7 functions. [Display omitted] [ABSTRACT FROM AUTHOR]

Aggregation is inevitable for the organic dyes, and it is difficult to evaluate its effects due to its complexity. Herein, we combine first principles and molecular dynamics (MD) simulations to explore the influence of aggregation on the optical and electronic properties for THI-BTZ-2T-C . If only the static properties are considered, the configuration of dye is not varied greatly when the adsorbed dyes are increased from monomer to hexamer. However, the absorption spectrum varies regularly with the increased aggregation order. In addition, the contribution of different orbitals of various atoms to density of states (DOS) gradually increases with the aggregation order increasing. When dynamics simulation is performed, the torsion between different components of dye is enlarged. Meanwhile, the perpendicular model is altered during the dynamics simulations, the dye would like to bend towards the TiO 2 surface. Moreover, the electronic coupling is greatly improved during the molecular dynamics simulations especially for the H-aggregation. The dye aggregation mainly affects the electrons injection process resulting in the reduction of the photoelectric conversion efficiency for dye sensitized solar cells (DSSCs). Reduction of perfect face to face stacking would be an efficient pathway to weaken the aggregation. [ABSTRACT FROM AUTHOR]

Two new indoline-based D-A-π-A dyes, D3F and D3F2 (see Scheme 1), are developed on the basis of the reported D3 by insertion of one or two F atoms on benzothiadiazole group. Our central aim is to explore high-efficiency organic dyes applied in dye-sensitized solar cells by inclusion of a simple group rather than by employment of new complicated groups. The performance of two new designed organic dyes, D3F and D3F2 , is compared with that of D3 from various aspects including absorption spectrum, light harvesting efficiency, driving force, and open-circuit voltage. Besides the isolated dye, the interfacial property between dye and TiO 2 surface is studied. D3F and D3F2 do not show absolute superiority than D3 not only for the isolated dyes but also for the monomeric adsorption system. However, D3F and D3F2 would effectively reduce the influence of aggregation resulting in the much smaller intermolecular electronic coupling. Although the aggregation has attracted much attention recently, it is studied alone in most of studies. To comprehensively evaluate the performance of dye-sensitized solar cells, it is necessary to consider aggregation along with electron injection time from dye into TiO 2 rather than only static items, such as, band gap and absorption region. [ABSTRACT FROM AUTHOR]

Four A-D-A-D-A organic dyes with different auxiliary acceptor or donor groups have been theoretically investigated by first principle as potential photosensitizers in dye-sensitized solar cells. Judging from the isolated dyes, 2PZ-SP with diphenyl-substituted pyrido[3,4-b]pyrazine-2,5-thiophene as auxiliary acceptor is not suitable to be taken as organic dye in DSSCs because of the inappropriate electron density distribution. However, it is difficult to distinguish the performance of other three dyes since no one has all superiorities. After the dye is adsorbed on TiO 2 surface, the deviation between LUMO energy level of dye and conduction band of TiO 2 (101) surface is further enlarged, which is favorable for the electron injection. Moreover, 2PZ-PP stands out because of the smallest H-L energy gap and the shortest injection time. Finally, a new D-π-A dye with the identical donor, π group, and acceptor groups is designed to compare with 2PZ-BT . It is found that 2PZ-BT has the absolute advantage to be potential dye for DSSCs. Besides the suitable groups, the appropriate configuration is more critical aspect to determine the performance. [ABSTRACT FROM AUTHOR]