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RNA methylations contribute to a wide range of cellular functions. Cellular RNAs are usually methylated by protein methyltransferases using S-adenosyl-l-methionine (SAM) as a cofactor. Here we report the in vitro selection of a 33-nucleotide SAM-dependent methyltransferase ribozyme RNA from a randomized sequence. Detection and mapping of the methyl group on the RNA demonstrates site-specific methylation of the N7 position of guanine by SAM. The ribozyme is active over a wide range of pH and temperatures and is robust compared to protein enzymes. The ribozyme structures in the presence and absence of SAM show a dramatic local conformational change associated with cofactor binding. The ribozyme motif was found to be distributed in nature, and candidate sequences were shown to be active in vitro. The discovery of this ribozyme that uses the cofactor SAM to specifically methylate RNA opens up the possibility that methyltransferase ribozymes may contribute to cellular RNA methylation. Ribozymes that use the cellular cofactor S-adenosyl-l-methionine to methylate RNA remained elusive. Now, such a ribozyme is reported by identifying natural sequences that are active in vitro; and crystal structures of the ribozyme with and without the cofactor are determined.

To improve the effect of pine rosin in plant fungicides, four series of dehydroabietyl-1,3,4-thiadiazole derivatives from the natural product rosin were synthesized. Based on the evaluation of the in vitro antifungal activity against Sclerotinia sclerotiorum, Botrytis cinerea, Fusarium oxysporum, and Magnaporthe oryzae, rosin-based 1,3,4-thiadiazole compounds containing thiophene heterocycles were screened. Notably, compound 3e [dehydroabietyl-(1,3,4-thiadiazol-2-yl)-5-nitrothiophene-2-carboxamide] exhibited excellent antifungal property against F. oxysporum with an EC50 of 0.618 mg/L, which was lower than that of the positive control carbendazim (0.649 mg/L). The in vivo antifungal activity results showed that 3e exerted a protective effect on cucumber plants. Physiological and biochemical studies showed that the primary mechanism of action of compound 3e on F. oxysporum was it changed the mycelial morphology, increased the cell membrane permeability, and inhibited the synthesis of ergosterol in the mycelia. Furthermore, the quantitative structure-activity relationship studies revealed that the frontier orbital energy in the molecule had a key role in the antifungal activity through the conjugation and electrostatic interaction between compound 3e and the receptors of the target. Thus, the present study highlighted the application of rosin-based fungicidal candidates and exploited efficient plant pesticides for sustainable crop production.

Sub wavelength double resonant cavity structures of oxides/metal/nitrides (OMN) for bolometric detection in the long wavelength infrared (LWIR) range are studied for the first time. An optimized OMN structure allows for a significant enhancement in effective absorbance (50%-70%) with respect to that of the bare film on an amorphous Al2O3 substrate (1-30%) in the LWIR atmospheric transparent window (8-14 μm). Remarkable improvement in the response range and sensitivity have been achieved by designing the double cavity OMN structure, where the bottom cavity originates from the high reflectance between the transition metal oxide film and the Al2O3 substrate, while the silicon nitride film on the top serves as a quarter wavelength anti-reflection cavity centered at about 8 μm. The OMN structured LWIR detector can be realized by cost effective methods of chemical solution deposition (CSD) or radio frequency (RF) sputtering deposition. A detectivity of 0.18-0.2×108 cm·Hz0.5/W@6-10 Hz was achieved by using the O...

In a continuous study on the high-value-added exploration of a renewable forest bioresource turpentine in modern organic agriculture, two series of α-pinene derivatives containing amide and α,β-unsaturated ketone pharmacophores were prepared. Through an in-depth fungicidal activity study, the title compounds presented excellent inhibitory activity against common crop fungi, especially Sclerotinia sclerotiorum, and the notable EC50 values of α,β-unsaturated compounds 3u (funan containing) and 3v (thiophene containing) were 1.657 and 1.749 μg/mL, respectively. Further physiological and biochemical studies on S. sclerotiorum revealed that compounds 3u and 3v reduced the ergosterol content in the cell membrane and increased the permeability of the cell membrane. In combination with their effect on mycelial morphology, the title compounds might have inhibitory effects on the biosynthesis of ergosterol, which is a paramount component of the target cell membrane. Moreover, quantitative structure-activity relationship (QSAR) and SAR studies revealed that the charge distribution of α,β-unsaturated carbonyl ketone derivatives played an important role in the observed fungicidal activity. In summary, this study highlights the design and development of novel high-efficacy turpentine-based antifungal agents.

The development of efficient terpenoid fungicides and exploration of its action mechanism is of great significance for the prevention and control of agricultural diseases. To confirm our previous findings on naturally occurring antifungal products with ecofriendly features, 40 terpene-based acyl-thiourea derivatives were synthesized and structurally characterized by 1H NMR, ESI-MS, elemental analysis and IR spectroscopy. Their inhibitory activities against several fungi, including Botrytis cinerea, Sclerotinia sclerotiorum and Thanatephorus cucumeris, were assessed by the growth rate method and the in vivo antifungal effects of these compounds against Thanatephorus cucumeris were performed evaluated using detached leaves. The majority of these compounds showed moderate to marked antifungal activities. Of all compounds, myrtenyl-based acylthiourea (8i) displayed more pronounced antifungal activity against Thanatephorus cucumeris (EC50 = 0.412 mg/L) compared with carbendazim (EC50 = 0.436 mg/L). In vivo antifungal of compound 8i efficiency against Thanatephorus cucumeris was also excellent. Treatment with 8i of Thanatephorus cucumeris resulted in significantly influenced morphology, markedly increased cell membrane permeability, and reduced ATP amounts and ATPase activity in comparison with untreated controls. A total of four descriptors linking structures and antifungal activities against Thanatephorus cucumeris were determined, including qSmax, HOMO-LUMO, log MS and qNmax, and employed to build a quantitative structure-activity relationship (QSAR) model (R2 = 0.9673). Preliminary structure-activity relationship (SAR) and QSAR assessments revealed that electronic and steric effects as well as energy differences of various molecules markedly affected antifungal effects. These findings provide novel insights into the modes of action of terpene-based acyl-thiourea derivatives, which could constitute potential substitutes for current fungicides or leads for novel antifungal agent development.

In the current work, we synthesized two series of dehydroabietyl amide derivatives from natural product rosin and evaluated their antifungal effects on Valsa mali, Phytophthora capsici, Botrytis cinerea, Sclerotinia sclerotiorum, and Fusarium oxysporum. In vitro and in vivo antifungal activities results indicated that rosin-based amide compounds containing thiophene heterocycles had better inhibitory effects on B. cinerea. In particular, compound 5b (5-fluoro-2-thiophene dehydroabietyl amide) exhibited the excellent antifungal properties against B. cinerea with an EC50 of 0.490 mg/L, which was lower compared to the positive control penthiopyrad (0.562 mg/L). Physiological and biochemical studies showed that the primary action mechanism of compound 5b on B. cinerea changes mycelial morphology, increases cell membrane permeability, and inhibits the TCA pathway in respiratory metabolism. Furthermore, QSAR and SAR studies revealed that charge distribution of rosin-based amides derivatives have a key role in the antifungal activity through the hydrogen bonding, conjugation, and electrostatic interaction between the compounds and the receptors of the target. To sum up, this study contributes to the development of rosin-based antifungal agents with a novel structure and preferable biological activity.

African swine fever virus (ASFV) is highly contagious and can cause lethal disease in pigs. ASFV is primarily replicated in the cytoplasm of pig macrophages, which is oxidative and caused constant damage to ASFV genome. ASFV AP endonuclease (AsfvAP) catalyzes DNA cleavage reaction at the abasic site and is a key enzyme of ASFV base excision repair (BER) system. Although it plays an essential role in ASFV survival in host cells, the basis underlying substrate binding and cleavage by AsfvAP remains unclear. Here, we reported the structural and functional studies of AsfvAP, showing that AsfvAP adopts a novel DNA-binding mode distinct from other APs. AsfvAP possesses many unique structural features, including one narrower nucleotide-binding pocket at the active site, the C16–C20 disulfide bond-containing region, and histidine-rich loop. As indicated by our mutagenesis, in vitro binding and cleavage assays, these features are important for AsfvAP to suit the acidic and oxidative environment. Owing to their functional importance, these unique features could serve as targets for designing small molecule inhibitors that could disrupt the repair process of ASFV genome and help fight against this deadly virus in the future.

NrS-1 is the first known phage that can infect Epsilonproteobacteria, one of the predominant primary producers in the deep-sea hydrothermal vent ecosystems. NrS-1 polymerase is a multidomain enzyme and is one key component of the phage replisome. The N-terminal Prim/Pol and HBD domains are responsible for DNA polymerization and de novo primer synthesis activities of NrS-1 polymerase. However, the structure and function of the C-terminus (CTR) of NrS-1 polymerase are poorly understood. Here, we report two crystal structures, showing that NrS-1 CTR adopts one unique hexameric ring-shaped conformation. Although the central helicase domain of NrS-1 CTR shares structural similarity with the superfamily III helicases, the folds of the Head and Tail domains are completely novel. Via mutagenesis and in vitro biochemical analysis, we identified many residues important for the helicase and polymerization activities of NrS-1 polymerase. In addition to NrS-1 polymerase, our study may also help us identify and understand the functions of multidomain polymerases expressed by many NrS-1 related phages.

Mitochondrial nucleases play important roles in accurate maintenance and correct metabolism of mtDNA, the own genetic materials of mitochondria that are passed exclusively from mother to child. MGME1 is a highly conserved DNase that was discovered recently. Mutations in MGME1-coding gene lead to severe mitochondrial syndromes characterized by external ophthalmoplegia, emaciation, and respiratory failure in humans. Unlike many other nucleases that are distributed in multiple cellular organelles, human MGME1 is a mitochondria-specific nuclease; therefore, it can serve as an ideal target for treating related syndromes. Here, we report one HsMGME1-Mn2+ complex and three different HsMGME1-DNA complex structures. In combination with in vitro cleavage assays, our structures reveal the detailed molecular basis for substrate DNA binding and/or unwinding by HsMGME1. Besides the conserved two-cation-assisted catalytic mechanism, structural analysis of HsMGME1 and comparison with homologous proteins also clarified substrate binding and cleavage directionalities of the DNA double-strand break repair complexes RecBCD and AddAB.

Chitin nanofibers extracted from crab shell were used to reinforce polylactic acid (PLA) by extrusion molding. The dispersion problem of nanofibers in PLA matrix was solved by three pretreatment methods, including water pretreatment, polyethylene glycol (PEG) pretreatment, and polyethylene oxide (PEO) pretreatment. The results demonstrated that chitin nanofibers were distributed uniformly on the fracture surface of the PLA matrix with three different pretreatment methods. However, the aspect ratio of nanofibers with was reduced with the PEG and PEO pretreatment methods. Therefore, the bending modulus (MOE), bending strength (MOR) and impact toughness of the chitin nanofibers/PLA composites prepared by the water pretreatment method were much higher than those of the composites prepared by the PEG and the PEO pretreatment method. Furthermore, the reinforcing effect with the PEG method is slightly better than that with the PEO method. Although it was found that both PEG and PEO were good interfacial compatibilizers for nanofibers and PLA, the reinforcing effect of the composites prepared by PEG and PEO pretreat methods was suppressed due to the decrease of the aspect ratio for chitin nanofibers.

In view of the great antifungal activities of sesquiterpene lactones and natural product Tulipalin A, 52 derivatives derived from α-methylene-γ-butyrolactone substructures were synthesized to study antifungal activities. In vitro and in vivo antifungal activity results revealed that compounds 2-25, which contain a γ-butyrolactone scaffold and cinnamic aldehyde moiety, have greater potent fungicidal activity than other compounds. The preliminary structure–activity relationships (SARs) demonstrated that compounds with electron-withdrawing groups and small steric hindrance would have more desirable potency. Meanwhile, the quantitative structure–activity relationship (QSAR) model (R2 = 0.947, F = 65.77, and S2 = 0.0028) revealed a convincing correlation of antifungal activity against B. cinerea with molecular structures of title compounds. The present study provided a more detailed insight into the antifungal activity of the α-methylene-γ-butyrolactone substructure, which provided a potential expectation for the exploration of α-alkenyl-γ-butyrolactone structures in agriculture.

In this paper, a high efficient terahertz source based on n-type gallium phosphide crystal via cryogenic process is investigated through collinear difference frequency generation pumper by 1064 nm Nd:YAG laser and its OPO system. Absorption coefficient of this crystal at THz range shows a dramatic decrease from ~ 50 cm-1 to 0.5 cm--1 as the temperature decreases from 300 k to 80 k. Four times enhancement of the terahertz emission power and much more broad spectra range (~ 0.2- 3.8 THz) has been achieved in this kind of 0.5 mm length gallium phosphide crystal during the whole varied temperature difference frequency generation from 300 k to 80 k. These results indicate that cooling down the crystal temperature is an effective way to improve the terahertz source property, such as terahertz output power and frequency range.

African swine fever virus (ASFV) is contagious and can cause highly lethal disease in pigs. ASFV DNA ligase (AsfvLIG) is one of the most error-prone ligases identified to date; it catalyzes DNA joining reaction during DNA repair process of ASFV and plays important roles in mutagenesis of the viral genome. Here, we report four AsfvLIG:DNA complex structures and demonstrate that AsfvLIG has a unique N-terminal domain (NTD) that plays critical roles in substrate binding and catalytic complex assembly. In combination with mutagenesis, in vitro binding and catalytic assays, our study reveals that four unique active site residues (Asn153 and Leu211 of the AD domain; Leu402 and Gln403 of the OB domain) are crucial for the catalytic efficiency of AsfvLIG. These unique structural features can serve as potential targets for small molecule design, which could impair genome repair in ASFV and help combat this virus in the future., The DNA ligase of African swine fever virus is one of the most error-prone ligases identified to date, but underlying molecular details are lacking. Here, Chen et al. report four AsfvLIG:DNA structures and identify a unique N-terminal domain and four unique active site residues that are crucial for its catalytic efficiency.

In view of potential agro activity of turpentine analogues, many studies have been conducted on the application of this biorenewable and abundant natural resource. Three series analogues of derivatives from volatile turpentine were prepared to study suitable amphipathic properties. The evaluation of fungicidal activity was carried out against three pathogenic microbials. In addition to the overall good effect, it was found that compounds 2-hydroxyethyl carboxylate, 5k, and 2-(2-hydroxyethoxy)ethyl carboxylate, 5l, demonstrated extreme activity, with IC50 values of 6.013 and 6.610 μg/mL against Setosphaeria turcica, which were close to the control carbendazim. The preliminary structure–activity relationship (SAR) was analyzed, and compounds with appropriate amphipathic features and small steric hindrance displayed more desirable performances. Meanwhile, the quantitative structure–activity relationship (QSAR) model (R2 = 0.9548, F = 47.82, S2 = 0.0125) was built and indicated that the most two important str...

Turning natural products into value-added herbicide preparation is an alternative to synthetic compounds for environmentally friendly weed management. In continuation of our research on rosin-based herbicidal agents, 33 acrylopimaric acid (APA) derivatives were synthesized, and were structurally characterized using proton nuclear magnetic resonance, elemental analysis, electrospray ionization mass spectra, melting point, infrared spectroscopy, and X-ray crystallography. In addition, the herbicidal activity of APA derivatives against Amaranthus retroflexus, Echinochloa crus-galli, and Brassica campestris L. were investigated. Among the APA derivatives, the diacylthiourea compounds 3a–f showed significant post-emergence herbicidal activity against E. crus-galli. Moreover, compounds 3b–d (with EC50 values of 13.191, 13.441, and 13.191 g ai/ha, respectively) displayed more promising herbicidal activity against E. crus-galli than sulfentrazone (a commercial herbicide with an EC50 value of 15.606 g ai/ha). In quantitative structure–activity relationship (QSAR) study, optimal conformers and best multilinear regression analysis were performed using Gaussian and CODESSA software. The four descriptors correlating the molecular structures with their herbicidal activities were as follows: Total Charge, log MS, qNmax and qCmax. The generated QSAR model had a correlation coefficient of 0.9625, a Fisher significance ratio of 185.96, and a squared standard error of the estimates of 0.0012. Preliminary studies on the structure–activity relationship and QSAR showed that the higher electron density around the substituent groups on the nitrogen atoms of rosin-based backbone structure and smaller volume of spatial structure played a beneficial effect on the herbicidal activity. Thus, rosin is a promising source of a value-added product for crop protection.

Rosin is extensively distributed and renewable natural resource in China. In continuation of our research on natural product-based insecticidal agents endowed with eco-friendly properties, 37 rosin-based amide derivatives containing thiadiazole group were prepared. Meanwhile, the structures of rosin-based derivatives containing thiadiazole group were characterized by melting point, IR spectroscopy, 1 H NMR, elemental analysis, ESI-MS and X-ray crystallography. In addition, the insecticidal activities of rosin-based amide derivatives containing thiadiazole group (3a–w and 7a–n) against Mythimna separata and Plutella xylostella were investigated. Compounds 3p–r, 7f and 7n (with LC 50 values of 0.222, 0.222, 0.224, 0.223 and 0.214 μg/mL) displayed outstanding insecticidal activity in comparison with flunbendiamide (a commercial insecticide, with LC 50 value of 0.222 μg/mL). The optimal conformers and best multilinear regression analysis were performed by Gaussian and CODESSA software package, and five descriptors correlating the molecular structures with their insecticidal activities were selected as follows: HOMO–LUMO, log MV, log P, Total Charge I and Total Charge II. For this built QSAR model, the correlation coefficient ( R 2 ) was 0.9604, the squared standard error of the estimates ( S 2 ) was 0.0052, and the Fisher significance ratio ( F ) was 103.79. The preliminary SAR and QSAR studies showed that electronic and steric effect of target compounds had an important influence on the larvicidal activity.

In order to investigate the effect of thiophene heterocyclic group on antifungal activity, two series of rosin-based derivatives were designed and synthesized. The antifungal effects on Thanatephorus cucumeris, Botrytis cinerea, Valsa mali, and Sclerotinia sclerotiorum were assessed. The dehydroabietyl acyl-thiourea compounds containing a thiophene heterocyclic group had mild to strong antifungal effects on V. mali. Among these molecules, compound 5e showed more excellent effects on V. mali with concentration for 50% of maximal effect (EC50) of 0.184 mg/L, which was lower than carbendazim. Compound 5e was also efficient against V. mali in vivo, with remarkably altered morphology, elevated cell membrane permeability, and decreased pectinase activity compared with the control group. Next, four parameters linking structural features and antifungal effects on V. mali were examined, including max net atomic charge for a S atom (qSmax), energy gap between the highest occupied molecular orbit and the lowest unoccupied orbit in atomic units (HOMO-LUMO), the logarithm of molecular surface area (log MS), and dipole moment (DM), and used for building a quantitative structure-activity relationship (QSAR) model (R2 = 0.9660). Preliminary structure-activity relationship (SAR) and QSAR evaluations indicated electronic and steric effects, and energy differences of different compounds had remarkable influences on antifungal properties. These results provided new insights into the mechanisms behind the antifungal properties of rosin-based with thiophene heterocyclic group derivatives. Guided by this study, some potential substitutes can be currently used in fungicides and some new antifungals can be led for developing.

In consideration of turpentine and its analogues possessing some agricultural biological activity, persistent efforts to take advantage of renewable, abundant natural resources have been made. Three series of derivatives from β-pinene were synthesized and their fungicidal activities against Rhizoctonia solani, Fusarium graminearum, and Botrytis cinerea were investigated. Most of the synthesized compounds exhibited moderate to significant fungicidal activity. Among them, the acylthiourea derivatives from β-pinene showed more promising results than the other compounds. It was worth noting that compounds 7b and 7d displayed excellent fungicidal activity against Rhizoctonia solani, with IC50 values of 2.439 and 1.857 μg mL−1, which was close to or even better than the control triadimenol (1.945 μg mL−1, a commercial fungicide). The structure–activity relationship (SAR) analysis indicated that the compounds with more net positive charge possessed better fungicidal activity. The quantitative structure–activity relationship (QSAR) model (R2 = 0.9879, F = 348.41, S2 = 0.0047) was obtained through the best multi-linear regression. The built model revealed a strong correlation of fungicidal activity against Rhizoctonia solani with the molecular features of the title compounds. Additionally, the SAR and QSAR studies showed that the introduction of an electron-withdrawing group, which can increase the positive charge, was favorable towards the fungicidal activity. These encouraging results may provide an alternative, promising use of β-pinene through the design and exploration of eco-friendly fungicides with low toxicity and high efficiency.

Mn-Co-Ni-O (MCNO) flexible thermistors are fabricated on polyethylene terephthalate or polyimide sheets by RF magnetron sputtering method at room temperature. The whole fabricating processes is completed at room temperature. The temperature coefficient of resistance (TCR) is -3.1% and resistivity as low as 110Ωcm at 295K. The bendingstraightening cycle test indicates the flexible MCNO sheet is stable. The temperature sensing test shows the thermistors respond to temperature change rapidly and sensitively. Due to the heat-treat free process, high TCR and moderate resistivity features, the technique we provide here allows a convenient and low cost industrial manufacture of high performance flexible thermistors and wide band infrared detectors.

Thin films of Mn1.4Co1.0Ni0.6O4 (MCN) spinel oxide are grown by radio frequency (RF) magnetron sputtering method on amorphous Al2O3 substrate. We investigate the annealing effect on the micro structural and electrical properties of RF sputtered MCN films. It is found that the crystallinity of MCN film is improved with increasing annealing time at 750 °C, and the annealed films present excellent cubic spinel (220) preferred orientation in X-ray diffraction patterns. Comparing to as-sputtered thin film, the annealed films show a decrease of 60 to 70 % in resistivity at 300 K. The annealed samples with post annealing time longer than 18 min acquire a negative temperature coefficient of resistance of about −3.73 %K−1 and resistivity of about 210–220 Ω cm at 300 K. 1/f noise of MCN films are also studied and the Hooge’s parameters (γ/n) are calculated. After annealing for 18 to 90 min, the γ/n values of the films are on the order of 10−21 cm3, which ranks about two orders lower than that of amorphous silicon.

In a continuing effort to develop novel natural product-based insecticidal agents endowed with low mammalian toxicity, two series of rosin-based diamides have been synthesized, and their insecticidal activities against Plutella xylostella and Mythimna separata were evaluated. Most of the synthesized compounds exhibited moderate to significant insecticidal activity. Among them, thiadiazole-containing diamides 6a–n displayed better activity than others, especially compounds 6f and 6n which exhibited excellent insecticidal activity against P. xylostella, with LC50 values of 0.223 and 0.214 mg L−1, respectively, which approximate to, or are lower than that of, the control flubendiamide (0.222 mg L−1). The preliminary structure–activity relationship analysis indicated that rosin-based diamides with electron-withdrawing groups on the benzene ring showed better insecticidal activity than those with electron-donating groups. Via a best multilinear regression analysis, the generated quantitative structure–activity relationship (QSAR) model (R2 = 0.9566) revealed a strong correlation of insecticidal activity against P. xylostella with molecular structures of these compounds. These consequences can be expected to instruct the design and development of new rosin-based insecticides.

African swine fever virus (ASFV) can cause highly lethal disease in pigs and is becoming a global threat. ASFV DNA Polymerase X (AsfvPolX) is the most distinctive DNA polymerase identified to date; it lacks two DNA-binding domains (the thumb domain and 8-KD domain) conserved in the homologous proteins. AsfvPolX catalyzes the gap-filling reaction during the DNA repair process of the ASFV virus genome; it is highly error prone and plays an important role during the strategic mutagenesis of the viral genome. The structural basis underlying the natural substrate binding and the most frequent dG:dGTP misincorporation of AsfvPolX remain poorly understood. Here, we report eight AsfvPolX complex structures; our structures demonstrate that AsfvPolX has one unique 5′-phosphate (5′-P) binding pocket, which can favor the productive catalytic complex assembly and enhance the dGTP misincorporation efficiency. In combination with mutagenesis and in vitro catalytic assays, our study also reveals the functional roles of the platform His115-Arg127 and the hydrophobic residues Val120 and Leu123 in dG:dGTP misincorporation and can provide information for rational drug design to help combat ASFV in the future., The African swine fever virus genome encodes the most distinctive DNA polymerase known, AsfvPolX. A structural and functional study reveals the basis for its strategic error-prone misincorporation of dGTP opposite a dG residue., Author summary African swine fever virus (ASFV) is highly contagious and can cause lethal disease in pigs. AsfvPolX catalyzes the gap-filling reaction during the DNA repair process of the virus genome; it is highly error prone and plays an important role in the strategic mutagenesis of the virus genome. Unlike the homologous proteins, AsfvPolX has several unique structural features, including a 5′-P binding pocket, a His115-Arg127 platform, and hydrophobic residues Val120 and Leu123, which can all affect the catalytic efficiency (especially during dG:dGTP misincorporation) of AsfvPolX. These properties, especially the 5′-P binding pocket, provide an ideal structural basis for designing of small molecules, which can specifically inhibit the activity of AsfvPolX and disrupt the DNA repair process of the ASFV genome.

In consideration of the fact that the α-methylene-γ-butyrolactone moiety is a major bio-functional group in the structure of carabrone and possesses some agricultural biological activity, forty-six new ester and six new ether derivatives containing α-methylene-γ-butyrolactone moieties were synthesized, and their fungicidal activities against Colletotrichum lagenarium and Botrytis cinerea were investigated. Most of the synthesized compounds showed moderate to significant fungicidal activity. Among them, halogen atom-containing derivatives showed better activity than others, especially compounds 6a,d which exhibited excellent fungicidal activity against C. lagenarium, with IC50 values of 7.68 and 8.17 μM. The structure-activity relationship (SAR) analysis indicated that ester derivatives with electron-withdrawing groups on the benzene ring showed better fungicidal activity than those with electron-donating groups. A quantitative structure-activity relationship (QSAR) model (R2 = 0.9824, F = 203.01, S2 = 0.0083) was obtained through the heuristic method. The built model revealed a strong correlation of fungicidal activity against C. lagenarium with the molecular structures of these compounds. These results are expected to prove helpful in the design and exploration of low toxicity and high efficiency α-methylene-γ-butyrolactone-based fungicides.

This paper reports on the synthesis of a series of amide derivatives from acrylopimaric acid (APA). The derivatives contained aromatic groups and were characterized by IR, 1HNMR, MS, and elemental analysis. The antibacterial activity of the derivatives against Gram-negative bacteria and Gram-positive bacteria were also investigated. When compared with the other derivatives, compounds 3a and 3f showed much higher activity against Escherichia coli (Gram-negative bacteria) with inhibition zones of 5 mm and 5.5 mm, respectively. Structure-activity relationship analysis revealed that ortho-substituted phenyl derivatives and meta-substituted phenyl derivatives exhibited higher activity than the para-substituted derivatives. Meanwhile, the halogen-substituted compounds did not show visible antibacterial activity compared with other compounds, which may have been caused by the lower electron density of the halogen-substituted phenyl rings.

Mn-Co-Ni-O (MCN) spinel oxide material, a very important transition metal oxide (TMO) with the best application prospects in information and energy fields, was discovered over five decades ago, but its applications have been impeded by the quality of its films due to the magnitude of deposition challenge. Here we report that high quality of MCN nanofilms can be achieved by sputtering deposition via acetate precursors whose decomposition temperatures are matched to the initial synthesis temperature of the MCN thin films. Excellent performance of MCN nanofilms is demonstrated, combining for the first time preferred orientation, high temperature coefficient of resistance and moderate resistivity. The film devices show an intrinsic recombination with a much faster rate of the order of a microsecond for the laser-pumped carriers, which is ~3 orders of magnitude larger compared with that of the ceramic material. The electronic structure of the thin films confirms that it is indeed of n-type nature, exhibiting appropriate electronic states consistent with the levels of metal electrodes and semiconductors. The results offer a vital avenue for depositing high performance TMO thin films for advanced oxide devices and will have great significance for exploiting new applications in modern oxide electronics and optoelectronics.

This study investigated whether treatment with IFN-α and ribavirin (RBV) reduces 2LTR circular HIV DNA in addition to the total and integrated HIV DNA. Two groups of patients were enrolled. Group 1 comprised HIV/HCV co-infected patients who were treated with highly active antiretroviral therapy (HAART), IFN-α and RBV for 48 weeks. After the 48 weeks of treatment, IFN-α and RBV treatment was discontinued and HAART was continued. Group 2 comprised HIV-infected patients who were treated with HAART. Real-time polymerase chain reaction (RT-PCR) was used to quantify the levels of HIV-1 DNA. We found that compared with Group 2 patients, Group 1 patients exhibited an obvious decrease in the CD4 cell count and the total DNA, 2LTR circular DNA, and integrated HIV DNA after 48 weeks of treatment. After the discontinuation of IFN-α and RBV treatment in Group 1 patients, the levels of HIV DNA recovered. Therefore, we concluded that treatment with IFN-α and ribavirin (RBV) reduces 2LTR circular HIV DNA.

Mn-Co-Ni-O spinel oxide materials, with the prototype of AB 2 O 4 , are excelled in uncooled thermal sensing and infrared detection due to its high absolute NTC value and moderate resistivity at room temperature. In this work, Mn 1.56 Co 0.96 Ni 0.48 O 4 film (MCN-CSD) and Mn 1.40 Co 1.00 Ni 0.60 O 4 (MCN-RF) film are fabricated on amorphous sapphire substrate with chemical solution method (CSD) and radio frequency deposition method (RF), respectively. Morphological characteristics are revealed by SEM graphs. And the result shows that MCN films acquire better crystalline properties and compactness than MCN bulk materials. To verify the excellent features for infrared detection, detectors sized 1mm 2 × 0.17 μm and 1 mm 2 × 0.33 μm are fabricated based on MCN-RF and MCN-CSD films, respectively. The excess noise at 11 Hz for each detector has been tested and the Hooge's parameters have been calculated. The MCN films obtained by RF deposition and CSD method both show γ/n value of about 2×10 -21 cm 3 , an order lower than bulk MCN and amorphous silicon, which indicates great potentials in integrated infrared detection.

Polymerase chain reaction (PCR) amplification of full-length HIV-1 envelope genes directly from uncultured clinical samples or from plasma of HIV patients using RT-PCR or from peripheral blood mononuclear cells (PBMC) DNA extracts of HIV patients is difficult. As HIV mainly infected CD4 positive cells, this paper first describes a sensitive method for the amplification of full-length HIV-1 envelope genes from purified CD4+ cells, and compares this method with other, less effective, procedures. This method were suitable for amplification of HIV-1 envelope genes directly from clinical samples especially from those of low viral load.