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By direct electrospinning poly(vinylidene fluoride) (PVDF)/Si3N4 blend solution on the Na2Ni[Fe(CN)6] electrode, a flexible separator@electrode combination is obtained. This combination is closely cross-linked by the -CH2 CF2- chain of β-PVDF in the separator and electrode, which delivers unique advantages in flexibility, thermal stability, tensile strength and interfacial resistance. Meanwhile, the PVDF/Si3N4 separator has a higher porosity (84.2%) and ionic conductivity (4.1 × 10−3 S cm−1), making the combination display an excellent electrochemical performance with a high initial coulombic efficiency of 96.8%, capacity retention rate of 92.2% after 503 cycles and rate capability of 78 mAh g − 1 at 5 C.

Preferred surface integrity around the hole wall is one of the key parameters to ensure the optimized performance of hole components for nickel-based superalloy. The novel hole cold expansion technique introduced in this work involves the laser texturing process (LTP) followed by the Hertz contact rotary expansion process (HCREP), where the cylindrical sleeve is the critical component connecting the above-mentioned two processes. The purpose of LTP is to obtain the most optimized strengthened cylindrical sleeve surface, preparing for the following HCREP. Hereafter, the HCREP acts on the nickel-based hole components by the rotary extruding movements of the strengthened sleeve and conical mandrel tools. As compared to the as-received GH4169 material, the surface integrity characterization for the strengthened hole shows that a plastic deformation layer with finer grains, higher micro-hardness, deeper compressive residual stress (CRS) distribution and lower surface roughness is formed at the hole wall. In addition, transmission electron microscope (TEM) observations reveal the microstructure evolution mechanism in the strengthened hole. Grain refinement near the hole wall is regarded as the fundamental reason for improving the surface integrity, where the aggregated dislocations and recombined dislocation walls can be clearly observed.

An improved precipitation method - electrostatic spray precipitation is proposed, which is characterized by introducing the electrostatic atomization effect into the precipitation process. The results display that electrostatic atomization can effectively reduce the size of reaction solution droplets under electrostatic force, the growth process of crystal nucleus is optimized, and then flake cluster MnCO3 is obtained, which further promotes the formation of homogeneous MnO nanoparticles. Compared with the agglomerated MnO without electrostatic action, homogeneous MnO nanoparticles exhibit better cycling stability (787 mAh g−1 after 100 cycles at 377.5 mA g−1) and rate capability (471 mAh g−1 at 3020 mA g−1).

Ceria, zirconia, Ce0.9Zr0.1O2, Ce0.75Zr0.25O2, and Ce0.5Zr0.5O2 samples were synthesized via the two-step hydrothermal method by using Ce(NO3)3·6H2O and Zr(NO3)4·5H2O as the precursors, respectively. The oxides were applied as catalysts for the dehydrogenation of ethylbenzene by using carbon dioxide as a soft oxidant (CO2-ODEB) at 550 °C and 0.1 MPa. Reaction results indicate that ceria was the most active catalyst while the zirconia with a cubic structure was inactive for CO2-ODEB. In the cases of the oxides by inserting Zr into CeO2, the activity indexed by either the initial ethylbenzene (EB) conversion or the calculated turnover frequency (TOF) at a time on stream of 1 h was changed in the sequence of Ce0.9Zr0.1O2 >> Ce0.75Zr0.25O2 > Ce0.5Zr0.5O2 while the decreasing pattern of the stability was observed in the order of Ce0.5Zr0.5O2 ≈ Ce0.75Zr0.25O2 >> Ce0.9Zr0.1O2. As revealed from the characterization results of XRD and Raman, the pure cubic solid solution of Ce1-xZrxO2 without any phase separations was obtained irrespective of the compositions. By correlating the characterization results, the activity of Ce1-xZrxO2 for CO2-ODEB was determined by the amount of the Ce3+ oxidized by CO2 and the rate of Ce3+/Ce4+ redox cycles. Moreover, both the coking rate and the promoting effect of the deposited coke on CO2-ODEB were responsible for the stability of Ce1-xZrxO2.

Reactive oxygen species (ROS) are the metabolites of oxygen that plays a significant role in cell signaling and homeostasis. Under normal conditions, ROS formation is stabilized by various antioxidant defense systems (ROS scavengers). Several studies in both in-vitro and in-vivo models, together with clinical data indicated that increased production ROS and oxidative stress plays a crucial role in the development and progression of endothelial dysfunction. The interactions between the main cellular sources of ROS, such as mitochondria and NADPH oxidases, however, remain unclear. The purpose of this review is to outline various sources of ROS and describe the crosstalk between NADPH oxidase and mitochondria. Further, we will discuss different antioxidants that lower ROS production and ROS-induced pathological conditions such as aging, atherosclerosis, diabetes, hypertension, and degenerative neurological disorders. In this review, we have mainly focused on antioxidants that inhibit NADPH oxidase and mitochondrial sources of ROS. Moreover, the modification of antioxidants (targeted therapy) may be a significant approach for management of oxidative stress induced pathophysiological complications.

The research provides a simple method for high-performance electrode preparation for use with a microbial fuel cell and microcurrent to treat pollutants. Blue titania nanotube arrays as a new microbial fuel cell electrode is synthesized by cathodic reduction. The results show that these arrays remarkably increase the electricity generation from 3.64 ± 0.112 mA to 6.246 ± 0.135 mA at the bioanode. A higher carrier concentration of 4.70 × 1024 cm−3, an apparent electron transfer rate constants of 21.69 ms−1 and drastic decrease in resistance to 1352 Ω provide better conditions for electroactive bacteria accumulation. The application of blue titania nanotube arrays to both the anode and cathode results in a photo-microbial fuel cell capable of efficient photoelectrocatalytic degradation of azo dye. The degradation of the azo dye and its intermediate products is attributed to electronic reduction of the dye and oxidation by free radicals.

This study constructed sediment microbial fuel cells (SMFCs) for polycyclic aromatic hydrocarbons (PAHs) removal in contaminated aquaculture sediment. Starch, a waste deposited in aquaculture sediment, was employed as the co-substrate for electricity generation and PAHs removal, and the effect of starch-derived organic acids on SMFC performance was assessed. The results indicated that sufficient starch promoted PAHs removal (69.9% for naphthalene, 55.6% for acenaphthene, and 46.8% for pyrene) in dual-chamber SMFC, whereas excessive starch attenuated SMFC performance because the organic acids accumulation reduced anode pH, decreased species diversity, and changed the microbial communities. The electricity generation and PAHs removal were positively correlated (R 0.96), and both of them were related to Macellibacteroides belonging to Bacteroidetes. However, a larger single-chamber SMFC device did not obtain enhanced PAHs removal owing to the restricted "effective range" of the anode. Hence, more challenges need to be addressed to realize the practical application of SMFC.

As a branch of intercalation type niobium-based anodes for lithium-ion batteries, Nb26Mo4O77 samples are synthesized by hydrothermal and solid-state method, respectively, while the structure and lithium-ion storage characteristics are studied in depth. Nb26Mo4O77 belongs to a monoclinic phase with ordered intergrowth ReO3 structure, which is constructed by a mixture of (Nb/Mo)O6 octahedra blocks of 3 × 4 × ∞ and 4 × 4 × ∞ occurring in alternate sequence and linked by MoO4 tetrahedra, favoring to the structural stability during the rapid lithium-ion deintercalation. Compared to agglomerated Nb26Mo4O77 microparticles synthesized via solid-state process, rod-like nanoparticles synthesized by hydrothermal method with the high specific surface area and reaction reactivity exhibit an improved initial coulombic efficiency (89.3%), notable cyclability (203 mAh g−1 after 503 cycles at 0.5 C), significant intercalation pseudocapacitive contribution (82.2% at 0.9 mV s−1) and increased rate capability (107 mAh g−1 at 10 C). These results provide some new supplements for the improvement of niobium-based anodes.

In this study, azo dye decolorization and degradation were realized in the air cathode of constructed wetland-microbial fuel cells (CW-MFCs). Additionally, the relationship between cathode and anode was studied. The cathode diameter was varied from 20 to 30 cm to study the cathode degradation and electricity generation performances, the effects of the cathode on the anode, and the influence of plants in the cathode layer. Different external resistances were applied to study the effects of current intensity on degradation and electricity generation performances. Cathode decolorization performance increased with increasing cathode diameter. Electricity generation performance first increased and then decreased with increasing cathode diameter. The highest decolorization volume (397.64 mg/L) was observed in the CW-MFC with a cathode 25 cm in diameter when the external resistance was 620 Ω. Meanwhile, it had a chemical oxygen demand removal volume of 317.65 mg/L. The highest cathode exchange current density (0.539 A/m2) was observed in the CW-MFC with a cathode 27.5 cm in diameter when the external resistance was 200 Ω. There were more electricity generation generas in the anode layer and there were more anaerobes and amphimicrobes in the larger cathode layer.

Microbial-fuel-cell-coupled constructed wetlands (CW-MFCs) with various cathode layers were used for long-term azo dye wastewater treatment. Their performance was assessed using cathode diameters ranging from 20 to 27.5cm and the influence of plants at the cathode was also examined. Bioelectricity generation, ABRX3 decolorization, and chemical oxygen demand (COD) removal performances first increased and then decreased with increasing cathode diameter. The CW-MFCs with larger cathodes had an anoxic region at the cathode where ABRX3 was decolorized. This phenomenon has not been reported in previous research on MFCs using traditional air cathodes. Anode performance was influenced by the cathode. The CW-MFC with a cathode diameter of 25cm showed the best electrode performance, and the highest voltage and power density were 560mV and 0.88W/m3, respectively. The highest ABRX3 decolorization and COD removal volumes were 271.53mg/L and 312.17mg/L, respectively.

In this study, a microbial fuel cell (MFC)-biofilm electrode reactor (BER) coupled system was established for degradation of the azo dye Reactive Brilliant Red X-3B. In this system, electrical energy generated by the MFC degrades the azo dye in the BER without the need for an external power supply, and the effluent from the BER was used as the inflow for the MFC, with further degradation. The results indicated that the X-3B removal efficiency was 29.87% higher using this coupled system than in a control group. Moreover, a method was developed to prevent voltage reversal in stacked MFCs. Current was the key factor influencing removal efficiency in the BER. The X-3B degradation pathway and the types and transfer processes of intermediate products were further explored in our system coupled with gas chromatography–mass spectrometry.

Heavy metal pollution is widespread in the environment. Microbial fuel cell (MFC) technology is effective for heavy metal removal; however, the simultaneous variations of multiple parameters in an MFC make it difficult to fully elucidate the mechanism of heavy metal removal under microcurrent conditions. In this study, we used a potentiostat to control the fixed potential in a simulated MFC system. The effects of pH, potential, and heavy metal concentration on current, heavy metal removal rate, product type, and product morphology were studied through orthogonal testing. The mechanism and significance of each parameter in terms of copper reduction removal were analyzed using tests of between-subjects effects and correlation analysis. We found that: (1) potential did not affect the type of electron acceptor, and substances with high redox potentials preferentially received electrons; (2) copper concentration significantly affected the reduction rate and product particle size of copper by controlling the flux of electroactive substances transferred to the electrode surface; (3) the combined effects of higher pH and copper concentration limited the reduction of copper; (4) current was the most important factor controlling copper reduction, as current strength significantly affected the copper reduction rate and mechanism; and (5) pH and copper concentration significantly affected the current level by altering the ionic strength of the solution.

Since licensure of human papillomavirus (HPV) vaccine in mainland China, little research has been conducted about healthcare providers' (HCPs) understanding and recommendation of HPV vaccine. A multi-stage convenience sample of Chinese HCPs (N = 5270) were surveyed, involving obstetrician-gynecologists, HCPs from Division of Expanded Program on Immunization (DEPI), Community Health Center (CHC) and other non-HPV closely related professions. Binary logistic regression was conducted to explore factors associated with knowledge and recommendation behaviors. Overall, HCPs showed basic HPV/HPV vaccine knowledge with median (interquartile range) score at 9.5 (7.5–11.6) out of 16 and relatively high recommendation behavior (74.8%). Identified knowledge gaps among HCPs included risk factors of HPV infection, best time to vaccinate, prophylactic functions of HPV vaccine and especially classification of low-risk and high-risk types. Profession-specific analysis in individual knowledge item showed HCPs from CHC were suboptimal on HPV while obstetrician-gynecologists were less competent on HPV vaccine knowledge. Obstetrician-gynecologists also recommended vaccination less frequently than HCPs from DEPI and CHC. Besides being key predictors of recommendation practice (2.74, 95% CI: 2.34–3.21), knowledge shared independent determinants with recommendation behavior on age and ethnicity and additionally associated with education and title by itself. Findings highlight overall and profession-specific gaps on HPV and HPV vaccine knowledge and recommendation practice. Future education and training efforts should be profession-niche-targeting and focus much on HCPs with lower title or education background and from minorities.

In order to explore how cutting parameters affect the evolution of subsurface defect of single crystal copper during nanocutting process, a nanocutting model is constructed based on LAMMPS; the nanocutting process of single crystal copper is investigated through molecular dynamics (MD) simulations for different cutting speeds and cutting depths, using EAM potential between Cu atoms and Morse potential between Cu atoms and the tool atoms. The results show that at the same cutting depth, cutting speed does not make much difference to the subsurface dislocation form; at the same cutting speed, cutting depth makes a great difference to the subsurface dislocation form and it also affects the crystal structure type of the defect layer very significantly. Under any cutting parameters, the dislocation form of 1/6 is dominant. With the increase of cutting speed and cutting depth, the dislocation of 1/6 and 1/3 of subsurface layer increased obviously, and the length of dislocation line also increased.

In this study, two double-anode microbial fuel cells (MFCs) were connected in series for degradation of the azo dye reactive brilliant red X-3B. After the series connection, the electricity generation of one of the MFCs decreased, and the other was not affected too much. Due to the special structure in the double-anode MFC reduced the imbalanced performance between the MFC units, the occurrence of voltage reversal was limited. The removal efficiencies in two MFC reactors were not consistent after the series connection, the results showed that the MFC with the reduced electricity generation had the higher removal efficiencies, it was 12.90, 11.66, and 40.05% higher than in the MFC in which the power generation capacity was not affected after the series connection, the MFC without serial connection, and the control group, respectively. Meanwhile, the microbial communities related to the degradation of refractory organic compounds increased and related to electricity generation decreased in the MFC with the reduced electricity generation, the changes of the microbial communities were consistent with its electricity generation and the removal efficiencies. The degradation products in the effluent from two MFC units showed that had the products generated from the MFC with the reduced electricity generation had simpler structures comparing the other MFC unit.

The machinability and tool wear behavior of 7050-T7451 aluminum alloy versus cutting parameters and vibration frequency are compared between conventional cutting (CC) and ultrasonic elliptical vibration cutting (UEVC) processes. A single-factor dry cutting experimental scheme is designed in light of the kinematic property of UEVC. The microstructural evolution in the cutting-layer metal are observed for different cutting parameters and vibration frequencies and the effects of these parameters on the tool wear behavior are investigated for both CC and UEVC. The results indicate that under the same cutting parameters, UEVC requires about three fifths the cutting force required by CC and provides a much higher cutting surface quality than CC. The cutting surface by UEVC shows visible precipitate-free zones (PFZs); the width and intermittent degree of the PFZs are obviously regionalized with vibration frequency, with a critical vibration frequency of 20,000 Hz. For CC, tool wear occurs typically in forms of tipping, spalling wear, or severe adhesive or oxidative wear, whereas for UEVC, tool wear typically mainly consists of impact-induced mechanical wear such as abrasive wear, mild oxidative wear and mild adhesive wear.

Microbial fuel cell (MFC) technology is widely used to remediate heavy metal pollution of soil, and the applicability of soils with different physical and chemical properties under micro-electric field has not been studied. In this study, copper was effectively removed in four typical soil-filled MFCs. The removal efficiencies of copper from closed-circuit MFCs filled with paddy, red, black and alluvial soils were 2.9, 1.50, 3.48 and 3.40 times higher than those in the open-circuit control group, respectively. However, the contributions of electromigration and diffusion mechanisms were different under different soil types. The greatest copper removal (19.3 ± 0.8%) was achieved based on electromigration of the electric field inside the paddy soil MFC in 63 days, while the greatest copper removal (25 ± 2%) was achieved under the action of diffusion mechanism inside the red soil MFC. According to redundancy analysis, the removal of copper by electromigration was positively correlated with electricity generation performance and acid extractable Cu content, whereas copper removal based on diffusion was positively related to soil pore volume and acid extractable Cu content. The cation exchange capacity and total organic carbon of soil were negatively correlated with the acid extractable Cu content, and electrical conductivity of soil was positively correlated with the MFC electricity generation performance. Furthermore, the directional movement of protons under an electric field alleviated the issue of soil acidification caused by citric acid.

Niobium tungsten oxide Nb16W5O55 is a competitive anode for lithium-ion batteries, while seldom research on low-temperature electrochemical properties. In this paper, Nb16W5O55 is synthesized by solid phase reaction and the effects of operation temperature (25, 0 and −20 °C) on the coulombic efficiency, cycling stability, rate capacity and crystal structure are studied in detail. At 25 °C, Nb16W5O55 electrode can give good cycling stability of 184 mAh g−1 after 404 cycles and rate capacity of 101 mAh g−1 at 4000 mA g−1. By contrast, the electrochemical properties decrease obviously at subambient temperatures. Electrochemical impedance spectroscopy reveal that the sharp increase of the charge-transfer impedance and the decrease of the solid-phase Li+ diffusion coefficient are the essential factors leading to the deterioration of low temperature performances. However, the low temperature mainly affects specific capacities and rate performances, but has little effect on cyclic stability and crystal structure of Nb16W5O55 electrode, indicated by ex-situ X-ray diffraction analysis. These results provide some new insights for the practical application of Nb16W5O55 anode.

Foraging selection of mammalian herbivores is thought to be not only governed by nutrients, but also influenced by plant secondary metabolites (PSMs) in their diets. Giant pandas (Ailuropoda melanoleuca) are well-known bamboo specialists and little is known about the effects of PSMs in bamboos on their foraging selection. Flavonoids are the most famous bioactive PSMs in bamboo leaves. Here, the spatiotemporal variation of total flavonoids (TF) and four typical carbon glycosides flavonoids (CGFs) (orientin, isoorientin, vitexin and isovitexin) in Bashania fargesii bamboo leaves in a vertical aspect and the association with altitudinal movement pattern of wild giant pandas were investigated. We found: (1) Both the TF and four CGFs in leaves of B. fargesii varied seasonally over elevations. Bamboo leaves in winter at higher elevation range were of the highest content. (2) Evident propensity of giant pandas for habitat selection exhibited in vertical direction. At the whole range of elevations B. fargesii distributed, giant pandas preferred to stay at 1600–1800 m. (3) The altitudinal preference of giant pandas and flavonoids in leaves of B. fargesii had significant positive correlations. The bamboo flavonoids at higher-elevation sites which were preferred by giant pandas were significantly higher than in lower-elevation area. (4) Validation in captive giant pandas showed those bamboo leaves unused in wild were of lower flavonoids especially the (iso)orientin compared to higher-elevation, which showed no differences with those unselected leaves in captivity. Our results indicate that the dietary flavonoids may be one of the driving factors shaping the altitudinal preference and diet selection of giant pandas which may be of significant physiological importance such as being playing key roles in the reproduction of such a dietary specialized species.

Previous studies have shown that entrepreneurial passion has a positive relationship with entrepreneurial intentions, however we do not know much about the underlying mechanisms that might mediate or moderate this relationship. This study extends the existing literature by examining the mediating role of innovativeness and the moderating role of curiosity in the entrepreneurial passion to entrepreneurial intentions relationship. Results, based on analysis of data collected from 295 respondents, showed that innovativeness partially mediated the entrepreneurial passion to entrepreneurial intentions relationship. Further, the mediating effect was stronger for individuals who scored high on curiosity than for individuals who scored low on curiosity. The present study contributes to a better understanding of the how, and the when of how, of the entrepreneurial passion to entrepreneurial intentions relationship.

As an environmentally sustainable bioelectrochemical technology, the microbial fuel cell (MFC) has attracted great attention. In this study, a three-chamber MFC (TC-MFC) was enhanced with different auxiliary reagents to remove heavy metals from soil. The results showed that the removal efficiency of heavy metals from soil increased with increasing auxiliary reagent concentration. When 1 mol/L citric acid, HCl, or acetic acid were used as an auxiliary reagent, the total copper (500 mg/kg) removal efficiency after 74 days of TC-MFC treatment was 3.89, 5.01 and 2.01 times that of the control group, respectively. The highest soil electrical conductivity (15.29 ms/cm), ionic heavy metal content (94.78%), electricity generation performance (363.04 mW h), and desorption stability of heavy metals were obtained when using 1 mol/L HCl as an auxiliary reagent, indicating that HCl was more suitable for the remediation of heavy metals in soil using a TC-MFC. Correlation analysis showed that the electricity generation of the TC-MFC was linearly related to the removal efficiency of heavy metals from soil (R2 = 0.9296). At the same time, higher content of ionic heavy metals in the soil led to better migration of heavy metals under the internal electric field of the TC-MFC.

The niobium tungsten oxide Nb12W11O63 is synthesized by a simple solid-state method and studied as an anode for lithium-ion batteries. By comparing with graphite anode, Nb12W11O63 with orthorhombic structure has higher safe working voltage (˃1.70 V) and tap density (∼2.57 g cm−3). The effect of cut-off voltage on the electrochemical property is also analyzed in detail. X-ray diffraction results reveal the mechanism of performance deterioration in Nb12W11O63 under deep discharge, which is caused by the collapse of crystal structure due to the transformation of pentagonal bipyramid to octahedron induced by excessive Nb3+. At the cut-off voltage of 1.3 V, Nb12W11O63 electrode delivers excellent electrochemical performances with high initial coulombic efficiency of 94.7%, improved cycling stability of 146 mAh g−1 after 404 cycles at 113 mA g−1 (78.8% of capacity retention) and good rate capacity of 100 mAh g−1 at 4520 mA g−1. These results indicate that Nb12W11O63 is a promising anode for lithium-ion batteries, and also provide the insight into the performance optimization of such materials.

The application of metal electrodes in microbial fuel cell (MFC) anodes is limited by their poor biocompatibility. In this study, needle-like Fe3O4/Fe2O3 nanorods were produced on 304 stainless steel plates by simple cyclic voltammetry (CV) treatment after anodization to enhance the current output. A maximum current of 7.11 ± 0.24 A/m2 was achieved after CV, twice as high as that without CV. The higher current output of the anode resulted from active redox substances involved in electron transfer. Analysis of the contact angle and laser scanning confocal microscopy showed that hydrophilicity promoted the enrichment of bacteria on the stainless steel. Therefore, this is a simple method for preparing high-performance electrodes.

In this study, a continuous-flow microbial fuel cell (MFC) system was constructed to treat azo dye wastewater for 400 days. The electrical properties of the MFC after 400-day operation and the removal efficiencies of the MFC after long- and short-term operation were analyzed with respect to co-substrate concentrations. The power output of the MFC system decreased from 586 to 330 mV with increasing operating time, and the removal efficiencies of the MFC remained stable after long-term operation in comparison to those after short-term operation, even when the co-substrate concentration was reduced. Analysis of the degradation products showed that products generated from long-term operation of the MFC were present at low concentrations. The microbial community analysis revealed that the relative abundance of microorganisms related to the degradation of organics in the MFC increased after long-term operation, and microorganisms related to electricity generation decreased.

Mouse ovarian surface epithelium (OSE) is a single layer of cubodial epithelial cells that covers the ovary surface and is involved in regulating the secretion and transport of 17β-hydroxysteroid dehydrogenase. Recently, OSE cells have attracted particular interest as a major source of ovarian cancer. Death-associated protein DAXX along with PML (promyelocytic leukemia protein) nuclear bodies (PML-NBs) reportedly play roles in transcriptional regulation and apoptosis. However, little is known regarding a role for DAXX in mOSE cells. In this study, we both over-expressed DAXX and depleted DAXX in primary mOSE cells. We found that Daxx deletion accelerated senescence in a p53/p21-dependent manner and promoted DNA damage by interacting with PML bodies without affecting cell cycle progression. These results suggest that DAXX may transform mOSE cells to an ovarian oncogenic phenotype and may be an anti-cancer target.

The aim of current study was to evaluate the prospects of somatostatin DNA vaccine. Two copies of somatostatin (SS) genes were fused with the hepatitis B surface antigen (HBsAg) S gene using genetic engineering methods, the identified recombinant plasmid designated as pcS/2SS was transfected into HeLa cells to detect expression and antigenicity of target fusion protein, and its immunoreaction as well as safety was evaluated with animal experiments. The expressed target protein had a specific reaction with somatostatin antibody and showed a single strip result. A single injection of this vector stimulated long-term antigen-specific antibody responses in rats, and peak antibody levels occurred at the 2nd week of the initial injection. Additionally, the 50 microg immunized group resulted in a 13.5% increase in growth rate as compared with control group (111.7 g vs. 98.4 g). The genomic DNA was assayed for integrated plasmid using a sensitive PCR method, and the risk of mutation due to integration of pcS/2SS plasmid following intramuscular injection in mice was negligible. The successful construction of pcS/2SS DNA vaccine with good immunogenicity and safety has prospects to promote growth of animals.

Many AIDS vaccine candidates under development may elicit immune responses similar to those observed in and used to screen human immunodeficiency virus type 1 (HIV-1)-infected individuals. Therefore, it is important to develop vaccine candidates that incorporate antigenic markers and allow vaccinees to be distinguished from HIV-1 infectees. To this end, we introduced a series of mutations into and in the vicinity of the major immunodominant region (MIR) of gp41 (residues 598–609), a domain recognized by almost all HIV-1 infectees, and evaluated whether HIV-1-like particles incorporating such mutant glycoproteins could be expressed in mammalian cells. Results indicated that although up to three consecutive amino acids could be replaced within MIR without significantly affecting particle formation or gp160 processing, deletions within MIR impaired envelope processing. Replacement of HIV-1 MIR by part or most of the corresponding domain from other lentiviruses markedly decreased or abolished gp160 processing. Synthetic peptides corresponding to a mutated MIR incorporating three amino acid replacements were not recognized by a panel of sera from HIV-1 infectees, suggesting that HIV-1-like particles with this type of mutation represent potential candidate vaccines that could allow vaccinees to be distinguished from HIV-1 infectees.