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Vegetative insecticidal proteins (VIPs), which were produced by Bacillus thuringiensis during its vegetative growth stage, display a broad insecticidal spectrum to Lepidoptera larvae. Sequence alignment of the Vip3A-type indicates that three cysteine residues were conserved in Vip3A-type proteins. To determine whether these conserved cysteine residues contributed to the insecticidal activity, the three residues were respectively substituted with serine in the Vip3Aa7 protein by site-directed mutagenesis. Bioassays using the third instar larvae of Plutella xylostella showed that the toxicity of C401S and C507S mutants were completely abolished. To find out the inactivity reason of mutants, three mutants and the wild-type Vip3Aa7 were treated with trypsin. The results indicated that the C507S mutant was rapidly cleaved and resulted in decrease of the 62 kDa toxic core fragment. These results indicated that the replacement of the Cys(507) with a Ser(507) caused decrease in C507S resistance against trypsin degradation. It is suggesting a possible association between insecticidal activity and trypsin sensitivity of Vip3A proteins. This study serves a guideline for the study of Vip3A protein structure and active mechanism.

Bacillus thuringiensis insecticidal crystal proteins (ICPs) and vegetative insecticidal proteins (VIPs) have been widely used as a kind of safe bio-insecticides. A problem that has been of concern worldwide is how to improve their insecticidal activities. In this study, to determine the synergism between VIPs and ICPs effect on insecticidal activity, a construct that produces a chimeric protein of the Vip3Aa7 and the N terminus ofCry9Ca, named V3AC9C, was expressed in Escherichia coli BL21 cells. In additional experiments, the V3AC9C chimeric protein, the single Vip3Aa7, and the single N terminus of Cry9Ca were treated with trypsin. SDS-PAGE showed that the V3AC9C could be processed into two single toxins. Bioassays tested on third instar larvae of Plutella xylostella showed that the toxicity of the chimeric protein was markedly better than either of the single toxins. Interestingly, the toxicity of the chimeric protein was 3.2-fold higher than a mixture of the Vip3Aa7 and Cry9Ca toxins (mass ratio of 1:1). The synergism factor (SF) of chimeric protein containing Vip3Aa7 and Cry9Ca was calculated to be 4.79. The SF in mixture of toxins is only 1.46. Hence, the effect was more than the sum of the Vip3Aa7 and Cry9C activities. Analysis of the protein's solubility showed that the Vip3Aa7 helped the N terminus of Cry9Ca to dissolve in an alkaline buffer. It was concluded that the increase in the toxicity of the V3AC9C chimeric protein over the constituent proteins mainly resulted from this increase in solubility. These results lay a foundation for the development of a new generation of bio-insecticides and multi-gene transgenic plants.

New palaeomagnetic and 40 Ar/ 39 Ar dating was carried out on the volcanic rocks and interbedded fossil-bearing lake sediments at the Sihetun section (northeast China) to determine the duration of deposition of the lacustrine sediments. The 40 Ar/ 39 Ar ages of the lower and upper volcanic rocks near the lava-sediment contacts are respectively 125.7 ± 2.6 Ma and 124.2 ± 2.5 Ma, which is in good agreement with a previously reported age of tuffs in the lake deposits. This is further supported by a normal palaeomagnetic polarity recorded by the whole lacustrine interval. With these palaeomagnetic investigations and new age controls, we conclude that the whole lacustrine interval at Sihetun was deposited within the normal polarity chron M3n (marine anomaly) during the Early Cretaceous. The possibly volcanic-associated ancient lake may have existed for a relatively short duration of less than 0.7 myr, assuming the M3n chron age to be between 124.72–124.04 Ma.

Windsor–Essex County is a major cross-border truck and transportation route, with significant localized industrialization as well as rural and farming areas. Magnetic property measurements (in-field and laboratory susceptibility, frequency-dependent susceptibility, hysteresis properties, thermomagnetic and thermosusceptibility curves, anhysteretic and isothermal magnetizations) were made in order to determine the potential for using such variables to distinguish between natural and anthropogenic pollutants. In-field magnetic susceptibility measured on 324 soil sampling sites on a 0.5–2 km grid spacing through Windsor–Essex County ranged from 3.7 × 10 − 6 to 305.2 × 10 − 6 SI (average 36.2 ± 35.8 × 10 − 6 SI), and showed that high magnetic susceptibility values were obtained on soil sampling sites in and around the cities/towns of Windsor, Harrow, Olinda and Oakland and near the beaches of Point Pelee National Park (PPNP) and Deerbrook, whereas lower susceptibility values were observed in near the towns of Lakeshore and Essex. On this grid spacing, Highway 401 (the major truck route) did not show anomalous susceptibility values; however, closer (1–3 m) sampling on other roads did show anomalously high values, suggesting that the coarser grid spacing may have missed anomalies. Laboratory measurements indicated that the dominant magnetic mineral in the Windsor–Essex County soils is magnetite; however, the grain size is variable. Pseudo-single domain (PSD)–multidomain (MD) magnetite is generally found on beaches and in PPNP, whereas single domain (SD)–PSD magnetite has been found near the City of Windsor and other towns. While certain correlations exist between some anthropogenic activities and the measured magnetic susceptibility and magnetic property values, no overall correlation can be made. A variety of geologic and anthropogenic factors must be considered when interpreting the origin of the magnetic signal in a particular area.

A precise 40Ar/39Ar age and paleointensity data for the Cretaceous lava flow from Chifeng, southern Inner Mongolia, northeastern China are presented in this study. Detailed rock magnetic investigations including the variation of magnetization with temperature, low temperature susceptibility and hysteresis loops show that pseudo single domain (PSD) grain size high-Ti titanomagnetite is the main magnetic mineral in the studied lava flow. Both the microwave and double heating Thellier techniques were used to determine the paleointensity, yielding mean flow paleointensities of 15.6 ± 3.2 μT and 23.9 ± 8.0 μT, respectively. However, the paleointensity results using the microwave technique are of higher quality (mean q = 12 for microwave compared to q = 2 for Thellier) and yield higher internal consistency for the flow mean (21% standard deviation about the mean for microwave compared to 34% for Thellier). The microwave paleointensity result, 15.6 ± 3.2 μT is therefore deemed the more reliable estimate for the paleointensity of the Niutoushan lava flow. 40Ar/39Ar age determination on the lava flow is 106.42 ± 0.48 Ma (2σ, relative to GA-1550 biotite: 98.79 ± 0.96 Ma). Combining our 40Ar/39Ar dating and paleointensity results with other published paleointensity data suggests that the intensity of the Earth's magnetic field during the middle Cretaceous normal superchron (CNS) was weak, but variable throughout the whole CNS.

SUMMARY Palaeomagnetic and rock magnetic study is reported of Early‐Middle Triassic terrestrial sediments from the Jiaocheng and Yushe areas, Shanxi province. Thermomagnetic analysis indicates that magnetite and haematite are the main magnetic carriers. Thermal demagnetization shows that the majority of Early Triassic specimens from the Jiaocheng area contain an intermediate-temperature component (ITC) between 500 ‐250 ◦ C and a high-temperature component (HTC) between 500‐680 ◦ C. The ITC has a negative fold test and might be a Cretaceous or recent overprint. The HTC contains both normal and reversed polarities with positive fold and C-level reversal tests. We interpret the HTC as primary magnetization. Unfortunately, we failed to isolate a meaningful mean direction from Middle Triassic rocks of the Yushe area. New Early Triassic palaeopole from the Jiaocheng area confirms an ∼ 10 ◦ counter-clockwise displacement of the Taihang Early Triassic palaeopoles relative to their Ordos counterparts. This study thus suggests that the North China block (NCB) has generally behaved as rigid block since the Early Triassic, but there might be an ∼9 ◦ counter-clockwise rotation of the Taihang terrane with respect to stable NCB in the Late Triassic. The slight rotation of the Taihang terrane does not bear significantly on what has been previously concluded concerning the Mesozoic history of the NCB—South China block (SCB) collision. However, Triassic palaeomagnetic data from stable NCB indicate that the east end of the NCB and SCB did not undergo large convergence or significant opposite latitudinal displacement after the initial contact at the end of the Late Permian.

Although the geomagnetic reversal record for the past 160 Myr is relatively well documented, whether a precursor exists before the onset of the Cretaceous normal superchron (CNS) remains a contentious topic in the study of the evolution of geomagnetic reversals. In the present study we have tried to find out if new paleointensity data can provide more information about this topic. A paleointensity, geochronologic and paleomagnetic investigation has been conducted on four andesitic basalt lava flows from Hulahada in Liaoning Province, northeastern China. Radiometric 40 Ar/ 39 Ar dating experiments indicate the volcanism occurred at about 122.7 ± 0.6 Myr, corresponding to marine anomaly Mln. Thermomagnetic experiments and hysteresis loops show that the main magnetic carrier of remanence are titanomagnetites with Curie temperatures of ∼580 °C. Thirty-eight samples from three lavas underwent Thellier–Thellier paleointensity experiments with systematic partial thermoremanent magnetization (pTRM) checks. Ten samples from the studied lavas yield reliable paleointensity estimates with a mean virtual dipole moment (VDM * ) of (4.8 ± 0.2) × 10 22 Am 2 , about half the strength of the modern-day field. Our paleointensity results in conjunction with previous data suggest that there is no precursor to the CNS.

In order to provide the age for the ISEA (one reversed event in the CNS) a combined rock magnetic, paleomagnetic and geochronologic study has been conducted on two Cretaceous andesitic basalt lava flows from Sanbaoying, Liaoning Province of northeastern China. Rock magnetic investigations show that pseudo-single domain (PSD) titanomagnetite with poor-Ti content is the dominant magnetic mineral in Sanbaoying lava flows. Detailed systematic thermal demagnetization allowed us to isolate two remanence components after removing a low temperature component at 100°C/150°C; an intermediate temperature component with normal polarity at 150°C/200°C–380°C/400°C and the characteristic remanence component (ChRM) with reversed polarity above 400°C/450°C.40Ar/39Ar dating results show that Sanbaoying rocks were erupted at 116.0 ± 0.3 Ma. Combination of paleomagnetic results and40Ar/39Ar dating indicates that the reversed event recorded in Sanbaoying lavas corresponds to the ISEA event in the CNS. Our age determination for ISEA reversed event provides chronological evidence to study the relevance between global geological events that occurred in the CNS and geodynamo processes.

A palaeomagnetic and geochronologic investigation has been conducted on a basalt lava sequence at Jianguo in Liaoning Province, northeastern China. Radiometric 40 Ar / 39 Ar dating experiments indicate the volcanism occurred in relatively short time intervals between 105.5 and 102.2 Ma. Thermomagnetic experiments and electron microprobe show that main primary carrier of remanence to be titanomagnetite with Curie temperature of ∼300 °C. A modified version of the Thellier–Thellier technique with systematic partial thermoremanent magnetization (pTRM)-checks was used for palaeointensity determinations. Fourteen out of 61 samples from the studied lavas yield reliable palaeointensity estimates with a mean virtual dipole moment (VDM*) of (4.07±0.2)×1022 Am2, about half the strength of the modern-day field.

A combined paleomagnetic and geochronologic study has been conducted on an andesite lava sequence at Jianguo (Liaoning province, northeastern China). Thermal demagnetization and thermomagnetic analysis revealed that natural remanent magnetization is carried by both magnetite and hematite. Stepwise thermal demagnetization up to 675°C isolated well-defined reverse characteristic remanent magnetization (ChRM) in three time-independent lava flows with a mean direction of D/I=179.2°/−59.7° with α95=3.0°. It also showed that a high-temperature component (>585°C) has the same ChRM direction as that of the low- to medium-temperature (ca. 170/300–585°C) components. A modified version of the Thellier–Thellier paleointensity method [Coe, J. Geophys. Res. 72 (1967) 3247–3262] with systematic partial thermoremanent magnetization checks was used for paleointensity determinations. Twelve out of 39 samples yielded reliable results in the temperature interval of 170–550°C. Virtual dipole moment values range from 3.9 to 4.7×1022 Am2 with an average of 4.2±0.1×1022 Am2. 40Ar/39Ar age determination on one lava flow is 116.8±3.0 Myr (2σ error, relative to Fish Canyon sanidine: 28.02±0.28 Myr). The magnetic reversed polarity with well-defined age could correspond to the ‘ISEA’ within the older part of the Cretaceous normal superchron (CNS), but we cannot rule out the possibility that this reversal interval could also correspond to the M0r due to many ambiguities on previous published ages on ISEA and M0r intervals as well as the new monitor age correction we applied. It also suggests that a weak magnetic field nature already documented before the CNS extended at least into the very beginning of the CNS.

A palaeomagnetic and geochronologic investigation has been carried out on a sequence of 19 lava flows at Sihetun in northeastern China. Age determinations by K/Ar dating indicate that the sequence spans 124–133 Ma, that is, the time just prior to Cretaceous normal superchron (CNS). Rock magnetic measurements of thermomagnetic curves and hysteresis loops show the primary carrier of remanence to be pseudo-single domain magnetite. Stepwise thermal demagnetization successfully isolated a well-defined direction of characteristic magnetization (ChRM) in all the lavas. The mean palaeodirection determined is D/I=5.4°/58.7° (α95=2.4°) and D/I=175.9°/−60.0° (α95=6.4°) for 15 normally magnetized flows and 3 reversely magnetized flows, respectively. One lava was found to possess an intermediate direction of magnetization. The inferred palaeolatitude of the sampling site is very similar to the present-day position, supporting the contention that suturing between the Mongolia and north China plates was probably completed by the Late Jurassic, and that subsequently little rotation or translation occurred in the region west of the Tanlu fault zone. Thellier–Thellier palaeointensity experiments with systematic partial thermoremanent magnetization (pTRM) checks were conducted on 66 samples from 13 lava flows. Results from the 29 samples (44%) which met strict reliability criteria indicate a range of virtual dipole moments (VDMs) from 2.83 to 4.17×1022 A m2 with an average of (3.53±0.02)×1022 A m2. This finding helps confirm that a weak geomagnetic field probably occurred just prior to the CNS.

Detailed rock magnetic studies of 55 lavas from Yixian and Fuxin area, West Liaoning, show the primary carriers of remanence to be pseudo-single domain titanomagnetite. K/Ar dating indicates that the volcanic sequence spans 93 to 133 Ma. Stepwise thermal demagnetization successfully isolated well-defined characteristic magnetization (ChRM) in all lavas thermal-treated above 250°C. The mean paleodirections are D/I=5.9ℴ/58.8ℴ (α95 = 2.9ℴ) and D/I =179.2ℴ/−59.9ℴ (α95 = 5.2ℴ) for 27 normally magnetized flows and 28 reversibly magnetized flows, respectively. It indicates that since the Early Cretaceous there is no significant horizontal movement and rotation between the Yixian-Fuxin area and Eurasia. However, Korea Peninsula may have undergone a clockwise rotation of 33.9ℴ relative to the Yixian-Fuxin area during the Cretaceous. On the basis of characteristics of hotspot origins (core-mantle boundary or upper mantle), the clockwise rotation of Korea Peninsula relative to Eurasia is assumed to be mainly caused by an extensional force in the crust of eastern China, which was corresponding to intensive surface volcanic activities in this area.

We report paleomagnetic results for Carboniferous rocks from the eastern part of the Hexi Corridor, which we have demonstrated to be the western extension of the North China block (NCB). The characteristic high-temperature remanence component (B-component) exhibits predominantly reverse polarity, and is generally separable by thermal demagnetization temperature steps between 350 and 580°C. This B-component can also be isolated by alternating fields (AFs) cleaning at a peak value of 20–30 mT using a hybrid thermal–AF demagnetization method. The B-component shows a positive fold test at the 95% confidence level, indicating that it was acquired before Late Triassic to Early Jurassic folding. We interpret the B-component to be of primary origin acquired during the Carboniferous. The corresponding pole positions are at 14.0°E, 10.5°N, α95=6.2° for the Early-Middle Carboniferous (late Visean to Namurian) and at 10.2°E, 33.3°N, α95=16.7° for the Late Carboniferous (Stephanian). The preliminary Late Carboniferous pole is in agreement with that for the NCB, supporting earlier claims that the Hexi Corridor has been the western extension of the NCB since the Ordovician. On the other hand, these two Carboniferous paleopoles are distinct from the coeval ones for Inner Mongolia, Outer Mongolia, South China, Tarim and stable Europe at greater than 95% confidence, suggesting that these continental blocks could not have been connected in their present configuration during Carboniferous time. The significant difference in paleolatitude between the NCB and Australian part of Gondwanaland according to the two new Hexi Corridor poles indicates that they had drifted apart by the late Visean.

Inhalational anthrax, caused by inhalation of the adversity-resistant spores, is a fatal disease, with a mortality rate approaching 80% (30). Although the naturally occurring inhalational form of anthrax is rare, malicious release of anthrax spores, particularly as weaponized anthrax spores, in a bioterrorism event kills civilians as well as creates great panic. This has stimulated the search for effective methods for the therapy and prevention of anthrax. The principal virulence factors of Bacillus anthracis consist of an antiphagocytic capsule composed of poly-d-glutamic acid (PGA) and a secreted bacterial toxin. The former is encoded by genes located on plasmid pXO1, and the latter is encoded by plasmid pXO2 (47). The anthrax toxin, which is predominantly responsible for the etiology of anthrax, belongs to the family of bacterial binary AB-type toxins, which consist of a receptor-binding B subunit known as the protective antigen (PA) and two catalytic A subunits, i.e., the lethal factor (LF) and edema factor (EF). PA combines with either LF or EF to form the lethal toxin (LeTx) and edema toxin (EdTx), respectively (47). Currently, the standard approach for anthrax therapy is to kill the germinating bacilli by administering aggressive antibiotics. However, antibiotic therapy is ineffective once systematic anthrax symptoms appear because by that time, fatal concentrations of the anthrax toxin have accumulated in the patient's body (41). Moreover, the emergence of antibiotic-resistant strains as a result of natural evolution or intentional modification by genetic engineering also poses a new challenge to traditional antibiotic treatment (13, 14). Therefore, the development of an antitoxin for combined use with antibiotic therapy is of high priority. At present, the process by which anthrax toxins enter cells and act is relatively well understood. Initially, the B subunit, i.e., the 83-kDa PA (PA83), binds to specific cell surface receptors through its C-terminal binding domain, and this is then proteolytically cleaved by furin or furin-like protease into a 20-kDa N-terminal fragment (PA20) and an active 63-kDa C-terminal fragment (PA63) (5, 15, 19, 28). After dissociation of PA20, cell-bound PA63 self-assembles into a ring-shaped homo-oligomer (heptamer or octamer) termed a prepore (18, 52). Simultaneously, the prepore competitively binds up to three molecules of LF and/or EF to form toxin complexes (9, 23, 33). These complexes are then internalized into the cells by receptor-mediated endocytosis and delivered to an endosome, where the acidic pH triggers the conformational transition of the prepore to generate the pore (31). Ultimately, LF and EF are translocated through the pore into the cytosol, where they exert their respective catalytic effects, leading to the manifestation of the anthrax symptoms (32). The elucidation of the molecular mechanism of anthrax toxin action has provided us with new strategies for developing antitoxins for anthrax treatment. To date, several potential antitoxins that target different steps of anthrax toxin intoxication are under development (37). The PA-binding domain of LF (LFn) or LFn-based fusion proteins is sufficient for binding to the PA63 formed prepore and can inhibit the anthrax toxin by competitively inhibiting the binding of LF to the prepore (1, 3, 20, 34). Another powerful antitoxin is the dominant-negative mutant of PA (DPA), which can be proteolytically activated to form dominant-negative inhibitory PA63 (DPA63). DPA63 coassembles with wild-type PA63 and blocks its ability to translate LF and EF (42, 46). On the basis of these findings, we decided to combine the competitive inhibitory activity of LFn and the dominant-negative inhibitory activity of DPA into a single-component reagent. Toward this end, we first constructed the chimera LFn-PA and demonstrated that this chimera could be proteolytically activated to produce an active PA63 moiety and a functional LFn-PA20 part. We then further replaced the PA moiety with a dominant-negative mutation, PAF427D, which has been described in sufficient detail elsewhere, to generate LFn-DPA (6, 21, 46). We next investigated the antitoxin potency of LFn-DPA in vitro and in vivo. Vaccination with the anthrax vaccine is the best strategy for preexposure prevention and postexposure prophylaxis (45). Now the only licensed anthrax vaccine for human use in the United States is the anthrax vaccine absorbed (AVA), also known as BioThrax. AVA has several disadvantages, such as batch-to-batch variation, an ill-defined composition, side effects, and a lengthy vaccination schedule (47). A second generation of vaccines based on highly purified recombinant PA (rPA) is under development. Although well-defined and homogeneous, rPA-based vaccines have immunogenicity and potency similar to those of AVA (17). This means that vaccination with rPA-based vaccines may be burdensome, just like vaccination with AVA. This underscores the need for developing new and more effective anthrax vaccines. Therefore, we evaluated the potential of LFn-DPA in anthrax prophylaxis.

Improved ant colony optimization (ACO) was applied to solve bin-packing problem. A tabu matrix bases on goods is established for ant colony optimization (ACO). Tabu matrix's every column corresponds to goods. Matrix has two rows, first row corresponds to goods load visit state, and second row corresponds to vehicle that ferries the goods. Ant state transfer probability is improved to solve bin-packing problem. According to ants tabu table, all the goods are searched by ants and satisfy the vehicle constrain. Illustrated with a practical case, ACO is feasible for bin-packing problem.

Logistics is divided into macroscopic logistics (also called social logistics) and microscopic logistics (also called enterprise logistics), according to microscope pattern and evolution line of TRIZ theory, this paper divides logistics into macroscopic logistics (social logistics), mesoscopic logistics (enterprise logistics) and microscopic logistics (individual logistics). we concentrate on microscopic logistics goods freight. We make use of integration pattern of evolution to integrate much single freight into super system. The selected technology is direct vehicular-customer communication (DV&CC) via radio transmission. It acts as intermediary in connection between vehicle and customer (v&c) in mobile ad hoc networks. In this way, we can make full use of nearby resource to meet customers' requirement at low cost, betimes and perfectly.

This paper describes a laboratory study of potential post-cold production strategies for heavy oil reservoirs. The tests were conducted on two primarily depleted long core systems (glassbeads core and sandpack core). The glassbeads core is 18.2 m in length with higher permeability (11.8 Darcy) and the sandpack core is 18.5 m long with lower permeability (1.9 Darcy). Both core systems were recharged by CH4 injection followed by a depletion step similar to the cold production experiment. Both cores were then exposed to a single cycle of CO2 injection, soaking and production. This work aims at further understanding the heavy oil solution gas drive mechanism. Furthermore, the study aims at assessing methane and carbon dioxide recharging as a potential recovery method for heavy oil reservoirs, and at establishing a base line for comparison against each other. Results of this study indicate that CH4 and CO2 recharge processes give an additional 8% and 9% OOIP recovery for the glassbeads core and the sandpack core, respectively. Since the cold production for the glassbeads core (22.2% OOIP) was high, the low recharge recoveries may be pessimistic. However, for the sandpack core, the recharge recovery appears more optimistic with almost similar recovery to that of cold production (about 10.2% OOIP).

[1] A paleomagnetic and geochronologic investigation has been conducted on 17 lava flows from Inner Mongolia, north China. Radiometric K-Ar dating experiments give an age between 23 and 22 Ma for these volcanic units. Rock magnetic measurements of thermomagnetic curves and hysteresis loops show the primary carrier of remanence to be pseudo-single domain titanomagnetite. Stepwise thermal demagnetization isolated a well-defined direction of characteristic remanent magnetization (ChRM) in all studied lava flows with a mean direction of D/I = 359.8°/62.2° (α95 = 3.8°). Fifty samples from 11 lavas were pre-selected on the basis of thermomagnetic analyses to carry out Thellier-Thellier paleointensity experiments with systematic partial thermoremanent magnetization (pTRM) checks. Twenty-three samples from 7 lavas yield reliable paleointensity estimates with a mean virtual dipole moment (VDM) of (3.9 ± 0.9) × 1022 Am2, about half the strength of the modern-day field.

We report a passively continuous wave (CW) mode-locked femtosecond 1.908 µm Tm:LiYF4 (Tm:YLF) slab laser based on an output-coupling graphene saturable absorber mirror (GSAM) with a transmittance of 2.29%. Using an atmospheric-pressure chemical vapor deposition (APCVD) method with a C2H2 carbon source, triple-layer graphene was fabricated and transferred to an output-coupling mirror of 1.9 µm wavelength range. Stable CW mode-locked laser pulses as short as 473 fs were measured with a repetition rate of 70.2 MHz and an average output power of 146.5 mW at 1.908 µm.