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There have been concerns that literature described radiological feature differences between drug-sensitive pulmonary tuberculosis (DS-PTB) and multidrug-resistant (MDR)-PTB were confounded by that MDR-PTB cases tend to have a longer history. Using history length matched DS-PTB and MDR-PTB cases from a well-defined urban region in Dalian, we retrospectively analysed the CT feature differences of these paired cases with a focus on pulmonary nodular (PN) consolidation and pulmonary cavity (PC).There were 33 consecutive MDR-PTB cases [inclusive of rifampicin-resistant (RR) cases, 27 males and 6 females, mean age: 49.2 years], with 19 cases had a history of1 month and 8 and 6 cases had a history of 1-6 and6 months respectively. To pair the MDR-PTB cases with history length, matched 33 cases of DS-PTB patients (21 males and 12 females, mean age: 56.5 years) were included. All patients were new PTB without HIV infection. The first CT exams prior to treatment were analysed.Compared with DS cases, MDR cases had a much higher prevalence of PN (75.76%MDR-TB is likely intrinsically more invasive than DS-TB. Multiple PN and Multiple PC are promising signs for the suspicion of MDR-PTB on chest imaging.

Cytochrome P450 monooxygenases (CYPs) are present in almost all areas of the tree of life. As one of the largest and most diverse superfamilies of multifunctional enzymes, they play important roles in the metabolism of xenobiotics and biosynthesis of endogenous compounds, shaping the success of insects. In this study, the CYPome (an omics term for all the CYP genes in a genome) diversification was examined in the four Tenebrionidea species through genome-wide analysis. A total of 483 CYP genes were identified, of which 103, 157, 122, and 101 were respectively deciphered from the genomes of Tebebrio molitor, Asbolus verucosus, Hycleus cichorii and Hycleus phaleratus. These CYPs were classified into four major clans (mitochondrial, CYP2, CYP3, and CYP4), and clans CYP3 and CYP4 are most diverse. Phylogenetic analysis showed that most CYPs of these Tenebrionidea beetles from each clan had a very close 1:1 orthology to each other, suggesting that they originate closely and have evolutionally conserved function. Expression analysis at different developmental stages and in various tissues showed the life stage-, gut-, salivary gland-, fat body-, Malpighian tubule-, antennae-, ovary- and testis-specific expression patterns of T. molitor CYP genes, implying their various potential roles in development, detoxification, immune response, digestion, olfaction, and reproduction. Our studies provide a platform to understand the evolution of Tenebrionidea CYP gene superfamily, and a basis for further functional investigation of the T. molitor CYPs involved in various biological processes.

Carboxylesterases (COEs) have various functions in wide taxons of organisms. In insects, COEs are important enzymes involved in the hydrolysis of a variety of ester-containing xenobiotics, neural signal transmission, pheromone degradation, and reproductive development. Understanding the diversity of COEs is basic to illustrate their functions. In this study, we identified 53, 105, 37, and 39 COEs from the genomes of Tenebrio molitor, Asbolus verucosus, Hycleus cichorii, and H. phaleratus in the superfamily of Tenebrionidea, respectively. Phylogenetic analysis showed that 234 COEs from these four species and those reported in Tribolium castaneum (63) could be divided into 12 clades and three major classes. The α-esterases significantly expanded in T. molitor, A. verucosus, and T. castaneum compared to dipteran and hymenopteran insects. In T. molitor, most COEs showed tissue and stage-specific but not a sex-biased expression. Our results provide insights into the diversity and evolutionary characteristics of COEs in tenebrionids, and lay a foundation for the functional characterization of COEs in the yellow mealworm.

In insects, serine proteases and serine protease homologs (SPs/SPHs) are involved in a variety of physiological processes including digestion, development, and immunity. Here, we identified 112 SP and 88 SPH genes in the genome of the yellow mealworm, Tenebrio molitor. Based on the features of domain structure, they were divided into "S" group containing single Tryp-SPc or Tryp-SPHc domain, "C" group containing 1-4 CLIP domain (CLIPA-D) and "M" group containing the CBD, CUB, EGF, Fz, Gd, LDLa, PAN, SEA, SR, Sushi, and TSP domains, and have 115, 48, and 37 gene members, respectively. According to the active sites in the catalytic triad, the putative trypsin, chymotrypsin, or elastase-like enzyme specificity of the identified SPs/SPHs were predicted. Phylogenetic and genomic location analyses revealed that gene duplication exists in the large amount of SPs/SPHs. Gene expression profiling using RNA-seq data along with real time reverse transcription-polymerase chain reaction analysis showed that most SP/SPH genes display life stage specific expression patterns, indicating their important roles in development. Many SP/SPH genes are specifically or highly expressed in the gut, salivary gland, fat body, hemocyte, ovary, and testis, suggesting that they participate in digestion, immunity, and reproduction. The findings lay the foundation for further functional characterization of SPs/SPHs in T. molitor.

Chitin is of great importance in the cuticle and inner cuticular linings of insects. Chitin synthases (CHSs), chitin deacetylases (CDAs), chitinases (CHTs), and β-N-acetylhexosaminidases (HEXs) are important enzymes required for chitin metabolism, and play essential roles in development and metamorphosis. Although chitin metabolism genes have been well characterized in limited insects, the information in the yellow mealworm, Tenebrio molitor, a model insect, is presently still unavailable. With the help of bioinformatics, we identified 54 genes that encode putative chitin metabolism enzymes, including 2 CHSs, 10 CDAs, 32 CHTs, and 10 HEXs in the genome of T. molitor. All these genes have the conserved domains and motifs of their corresponding protein family. Phylogenetic analyses indicated that CHS genes were divided into two groups. CDA genes were clustered into five groups. CHT genes were phylogenetically grouped into 11 clades, among which 1 in the endo-β-N-acetylglucosaminidases group and the others were classified in the glycoside hydrolase family 18 groups. HEX genes were assorted into six groups. Developmental and tissue-specific expression profiling indicated that the identified chitin metabolism genes showed dynamical expression patterns concurrent with specific instar during molting period, suggesting their significant roles in molting and development. They were predominantly expressed in different tissues or body parts, implying their functional specialization and diversity. The results provide important information for further clarifying their biological functions using the yellow mealworm as an ideal experimental insect.

Serine protease inhibitors (SPIs) act in diverse biological processes in insects such as immunity, development, and digestion by preventing the unwanted proteolysis. So far, the repertoire of genes encoding SPIs has been identified from few insect species. In this study, 62 SPI genes were identified from the genome of the yellow mealworm, Tenebrio molitor. According to their modes of action, they were classified into three families, serpin (26), canonical SPI (31), and α-macroglobulins (A2M) (5). These SPIs feature eight domains including serpin, Kazal, TIL, Kunitz, WAP, Antistasin, pacifastin, and A2M. In total, 39 SPIs contain a single SPI domain, while the others encode at least two inhibitor units. Based on the amino acids in the cleaved reactive sites, the abilities of these SPIs to inhibit trypsin, chymotrypsin, or elastase-like enzymes are predicted. The expression profiling based on the RNA-seq data showed that these genes displayed stage-specific expression patterns during development, suggesting to us their significance in development. Some of the SPI genes were exclusively expressed in particular tissues such as hemocyte, fat body, gut, ovary, and testis, which may be involved in biological processes specific to the indicated tissues. These findings provide necessary information for further investigation of insect SPIs.

Cell division and differentiation after egg fertilization are critical steps in the development of embryos from single cells to multicellular individuals and are regulated by DNA methylation via its effects on gene expression. However, the mechanisms by which DNA methylation regulates these processes in insects remain unclear. Here, we studied the impacts of DNA methylation on early embryonic development in细胞分裂和分化是胚胎从受精卵发育成多细胞个体的重要步骤，DNA甲基化通过调控基因表达而影响胚胎发育的过程。然而，昆虫DNA甲基化调控胚胎发育的机制仍不清楚。该文研究了DNA甲基化对家蚕早期胚胎的影响。早期胚胎的DNA甲基化组和转录组分析表明，5-甲基胞嘧啶（5mC）主要发生在蛋白质代谢相关基因的基因体5’端区域。DNA甲基转移酶1（Dnmt1）催化转录因子锌指蛋白615（

ATP-binding cassette (ABC) transporters, one of the largest transmembrane protein families, transport a diverse number of substate across membranes. Details of their diverse physiological functions have not been established. Here, we identified 87 ABC transporter genes in the genomes of Tenebrio molitor along with those from Asbolus verrucosus (104), Hycleus cichorii (65), and Hycleus phaleratus (80). Combining these genes (336 in total) with genes reported in Tribolium castaneum (73), we analyzed the phylogeny of ABC transporter genes in all five Tenebrionids. They are assigned into eight subfamilies (ABCA-H). In comparison to other species, the ABCC subfamily in this group of beetles appears expanded. The expression profiles of the T. molitor genes at different life stages and in various tissues were also investigated using transcriptomic analysis. Most of them display developmental specific expression patterns, suggesting to us their possible roles in development. Most of them are highly expressed in detoxification-related tissues including gut and Malpighian tubule, from which we infer their roles in insecticide resistance. We detected specific or abundant expressions of many ABC transporter genes in various tissues such as salivary gland, ovary, testis, and antenna. This new information helps generate new hypotheses on their biological significance within tissues.

The Wnt gene family is involved in a wide range of developmental processes. Despite its significance, the evolution and function of Wnt genes remain largely unclear. Here, an exhaustive survey of Wnt genes was conducted in Tenebrio molitor and 17 other beetle genomes. A total of 146 Wnt genes were identified, creating a comprehensive coleopteran Wnt gene catalog. Comparative genomics indicates that dynamic evolutionary patterns of Wnt gene loss and duplication occurred in Coleoptera, leading to the diverse Wnt gene repertoire in various beetles. A striking loss of particular Wnt gene subfamilies occurs in Coleoptera. Remarkably, Wnt gene duplication was discovered for the first time in insects. Further analysis of Wnt gene expression in T. molitor indicates that each Wnt gene, including the duplicated ones, has a unique spatial or temporal expression pattern. The current study provides valuable insight into the evolution and functional validation of Wnt genes in Coleoptera.

Cadmium (Cd) pollution is intractable heavy metal pollution in the farmland ecosystem, posing a life-threatening challenge to the paddy field organisms. Spiders are riveting animal biomarkers for evaluating Cd-induced toxicity, yet the effects of long-term Cd toxicity on spider reproductive function and its underlying mechanism remain unclear. In the present study, we found that Cd exposure impaired the antioxidant enzyme system in the wolf spider Pardosa pseudoannulata and decreased the concentration of four antioxidant enzymes (catalase, glutathione peroxidase, superoxide dismutase, and peroxidase) (p 0.05). The content of vitellogenin and the number of hatched spiderlings were also dramatically reduced under Cd stress (p 0.05), indicating that Cd stress could vitiate the fecundity of P. pseudoannulata. Moreover, a total of 10,511 differentially expressed genes (DEGs) and 391 proteins (DEPs) were yielded from the ovarian transcriptome and proteome, and a mass of genes and proteins involved in protein processing in endoplasmic reticulum (ER) were significantly down-regulated. DEGs and DEPs directly encoding the antioxidant enzyme system and/or vitellogenesis were also distinctively down-regulated. In addition, we illustrated that the PI3K-AKT signaling pathway might play a crucial role in regulating protein synthesis, cell cycle, growth, differentiation and survival in P. pseudoannulata. The effects of protein processing in ER and PI3K-AKT pathways could further trigger transcriptional factor Forkhead shackling the protein synthesis and cell growth process. Collectively, this integrated analysis identified the Cd-induced reproductive toxicity on P. pseudoannulata and provided multifaceted insights to investigate the molecular mechanisms of spiders to Cd pollution.

Cadmium (Cd) pollution is one of the most serious heavy metal pollutions in the world, which has been demonstrated to cause different toxicities to living organisms. Cd has been widely suggested to cause reproductive toxicity to vertebrates, yet its reproductive toxicity to invertebrates is not comprehensive. In this study, the wolf spider Pardosa pseudoannulata was used as a bioindicator to evaluate the male reproductive toxicity of invertebrates under Cd stress. Cd stress had no effect on the color, size and length of testis. However, Cd significantly increased the contents of catalase, glutathione peroxidase and malondialdehyde, the antioxidants in the testis of P. pseudoannulata. Then we analyzed the transcriptome of testis exposed to Cd, and identified a total of 4739 differentially expressed genes (DEGs) compared to control, with 2368 up-regulated and 2371 down-regulated. The enrichment analysis showed that Cd stress could affect spermatogenesis, sperm motility, post-embryonic development, oxidative phosphorylation and metabolism and synthesis of male reproductive components. At the same time, the protein-protein interaction network was constructed with the generated DEGs. Combined with the enrichment analysis of key modules, it revealed that Cd stress could further affect the metabolic process in testis. In general, the analysis of testicular damage and transcriptome under Cd stress can provide a novel insight into the reproductive toxicity of Cd on rice filed arthropods and offer a reference for the protection of rice filed spiders under Cd pollution.

Transition metal catalysts have been considerably used for NH3 decomposition because of the potential application in CO x -free H2 generation for fuel cells. However, most transition metal catalysts prepared via traditional synthetic approaches performed the inferior stability due to the agglomeration of active components. Here, we adopted an efficient method, aerosol-assisted self-assembly approach (AASA), to prepare the optimized cobalt-alumina (Co3O4-Al2O3) catalysts. The Co3O4-Al2O3 catalysts exhibited excellent catalytic performance in the NH3 decomposition reaction, which can reach 100% conversion at 600 °C and maintain stable for 72 h at a gaseous hourly space velocity (GHSV) of 18000 cm3 gcat−1 h−1 . The catalysts were characterized by various techniques including transmission electron microscope (TEM), scanning electron microscope (SEM), nitrogen sorption, temperature-programmed reduction by hydrogen (H2-TPR), ex - situ / in - situ Raman and ex - situ / in - situ X-ray diffraction (XRD) to obtain the information about the structure and property of the catalysts. H2-TPR and in - situ XRD results show that there is strong interaction between the cobalt and alumina species, which influences the redox properties of the catalysts. It is found that even a low content of alumina (10 at%) is able to stabilize the catalysts due to the adequate dispersion and rational interaction between different components, which ensures the high activity and superior stability of the cobalt-alumina catalysts.

The bark beetle, Tomicus yunnanensis (Coleoptera: Scolytinae), is a seriously destructive pest of Yunnan pine (Pinus yunnanensis) and is distributed solely in Southwestern China. It has been a challenge to control this pest owing to its resistance to chemical pesticides, which have been used as the main control strategy of this species in recent years. Since this approach will continue until an alternative mitigation strategy is implemented, it is essential to develop novel or improved biocontrol approaches. In the current study, we aimed to identify most, if not all, of the bark beetle's chemosensory genes, and to address their respective phylogenetic relationships and expression characteristics. Digital gene expression (DGE) profiling and a comparison of the profiles at three developmental stages yielded 40,287,265 clean reads and a large number of differentially expressed genes (DEGs), with 21 up- and 20 down-regulated DEGs involved in chemoreception. Transcriptome of the three mixed stages revealed a total of 80 transcripts encoding chemosensory-related proteins comprising 45 odorant-binding proteins (OBPs), 12 chemosensory proteins (CSPs), 20 receptor proteins [9 odorant receptors (ORs), 8 gustatory receptors (GRs) and 3 ionotropic receptors (IRs)] and 3 sensory neuron membrane proteins (SNMPs). As many as 38 full-length sequences were acquired with a combination of transcriptomic analysis and rapid amplification of cDNA ends (RACE) strategy. Phylogenetic analysis showed that T. yunnanensis OBPs were clustered into four sub-groups: 27 Minus-C OBPs, 5 antennal binding proteins (ABPIIs), 10 Classic OBPs and one Plus-C OBP; meanwhile, the ORs were grouped into four clades (1, 2, 7b and Orco). Expression profiles revealed that 66 of 80 genes were detected in the three DGE libraries, and 15 soluble olfactory proteins were antennae-predominant, possibly guiding olfactory-associated behaviors of this beetle. Taken together, our study has provided valuable data for further functional studies of this beetle and will facilitate the identification of potential molecular targets associated with chemosensory reception for use in biocontrol strategies.

For decades, it is fairly controversial whether the active gold sites in catalyzing CO oxidation reaction are metallic or positively charged. Herein, catalysts with either metallic or positively charged gold were separately prepared by deposition–precipitation method with the same type of TiO2 matrix. The catalytic behaviors in CO oxidation reaction were observed for two catalysts. For the initially inactive Aun+/TiO2 (1 < n < 3) catalyst, the in situ diffuse-reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) exhibited that CO induced the transformation from Aun+ to Au0 during reaction. The conversion of gold state resulted in an enhanced CO adsorption ability and further increased the catalytic reactivity. Additionally, the in situ Raman results proved that the formation of Au0 from Aun+ might be in favor of generating oxygen vacancy in TiO2 matrix, which was beneficial for O2 activation. Therefore, we reasonably established that the Au0 was more active than Ann+ in catalyzing the CO ox...

Copper-ceria sheets catalysts with different loadings of copper (2, 5 and 10 wt.%) supported on ceria nanosheets were synthesized via a deposition-precipitation (DP) method. The prepared catalysts were systematically characterized with various structural and textural detections including X-ray diffraction (XRD), Raman spectra, transmission electron microscopy (TEM), X-ray absorption fine structure (XAFS), and temperature-programmed reduction by hydrogen (H 2 -TPR), and tested for the CO oxidation reaction. Notably, the sample containing 5 wt.% of Cu exhibited the best catalytic performance as a result of the highest number of active CuO species on the catalyst surface. Further increase of copper content strongly affects the dispersion of copper and thus leads to the formation of less active bulk CuO phase, which was verified by XRD and H 2 -TPR analysis. Moreover, on the basis of in-situ diffuse reflectance infrared Fourier transform spectroscopy ( in-situ DRIFTS) results, the surface Cu + species, which are derived from the reduction of Cu 2+ , are likely to play a crucial role in the catalyzing CO oxidation. Consequently, the superior catalytic performance of the copper-ceria sheets is mainly attributed to the highly dispersed CuO x cluster rather than Cu-[O x ]-Ce structure, while the bulk CuO phase is adverse to the catalytic activity of CO oxidation.

Nanostructured mixed metal oxides with porous hollow-interior structure hold great promise in environmental-related catalysis, owing to their excellent catalytic properties. However, facile fabrication of such mesoporous architecture is still challenging. Here, by using a transient aerosol-assisted self-assembly (AASA) method, we synthesized the Co3O4-Al2O3 mesoporous hollow spheres (MHS) composed of thermally stable Co3O4 nanoparticles partially anchored to amorphous interfacial Al2O3. The as-prepared Co3O4-Al2O3 nanocomposites displayed distinct features of large pore volume and stable assembled morphology, and thus showed significant advantages in mass transfer and redox behavior. For Fischer-Tropsch synthesis, a very important reaction in fuel production, the Co3O4-Al2O3 MHS exhibited significant catalytic performance in conversion, selectivity and stability for the desired gasoline products. Therefore, we provide a facile and controlled approach towards the preparation of mesoporous hollow materials to achieve novel mixed metal oxide nanocatalysts those are good candidates in energy-production application.

The brown planthopper (BPH), Nilaparvata lugens, is a resurgent pest with an unexpected response to jinggangmycin (JGM), a broadly applied antibiotic used to control rice sheath blight disease. JGM stimulates BPH fecundity, but the underlining molecular mechanisms remain unclear. Here we report that JGM sprays led to increased glucose concentrations, photosynthesis and gene expression, specifically Rubsico, sucrose phosphate synthase, invertase 2 (INV2) and INV3 in rice plants. JGM sprays led to high-glucose rice plants. Feeding BPH on these plants led to increased insulin-like signaling and vitellogenin synthesis. Treating BPH with metformin, a gluconeogenesis inhibitor, reversed the influence of feeding on high-glucose rice, which was rescued by glucose injections. Silencing insulin-like peptide 2 using per os dsRNA led to reduction in juvenile hormone (JH) III titers and other fecundity parameters, which were reversed by topical applications of the JH analog, methoprene. We infer that JGM acts via two broad mechanisms, one through increasing rice plant sugar concentrations and a second by upregulating BPH insulin-like signaling.

The antibiotic jinggangmycin (JGM) is broadly applied in Chinese rice producing regions to control rice blight, a fungal disease. Aside from protecting rice plants from the disease, JGM leads to the unexpected action of stimulating brown planthopper (BPH; Nilaparvata lugens; Hemiptera: Delphacidae) reproduction to the extent it can influence population sizes. The JGM-induced BPH population growth has potential for severe agricultural problems and we are working to understand and mitigate the mechanisms of the enhanced reproduction. UDP-glucuronosyltransferases (UGTs) are multifunctional detoxification enzymes responsible for biotransformation of diverse lipophilic compounds. The biological significance of this enzyme family in insect fecundity is not fully understood, however, upregulated UGT12 in JGM-treated BPH, may influence fecundity through metabolism of developmental hormones. This idea prompted our hypothesis that NlUGT12 is a positive modulator of BPH reproductive biology. JGM treatment led to significant increases in accumulations of mRNA encoding NlUGT12, numbers of eggs laid, oviposition period, juvenile hormone III titers, and fat body, and ovarian protein contents. dsUGT12 treatment suppressed NlUGT12 expression and reversed JGM-enhanced effects, resulting in under-developed ovaries and reduced expression of juvenile hormone acid methyltransferase and the JH receptor, methoprene tolerant. Application of the JH analog, methoprene, on dsUGT12 treated-females partially reversed the dsUTG12 influence on vitellogenin synthesis and on NlUGT12 expression. These results represent an important support for our hypothesis.

High-surface-area Co-SiO2 nanocomposites were synthesized by a simple two-step procedure with activated carbon as the template. These materials catalyze the decomposition of ammonia to produce COx -free hydrogen. The fresh and used catalysts were characterized by various techniques including X-ray diffraction, N2 adsorption-desorption, and transmission electron microscopy. Furthermore, temperature-programmed reduction by hydrogen combined with the corresponding in situ XRD analysis was performed to investigate the redox properties of the as-prepared catalysts. The strong interaction between the cobalt species and silica can effectively prevent the active cobalt nanoparticles from agglomerating during calcination and the ammonia decomposition reaction. The ammonia reaction rate reached about 7000 mol NH3 molCo-1 h-1 with a very high GHSV of 124 000 cm3 gcat-1 h-1 at 600 °C; this rate was maintained for 48 h without any observable deactivation of the as-obtained Co-SiO2 nanocomposite catalyst.

Copper–ceria catalysts with the Cu contents up to 40 at.% were prepared by the coprecipitation method. Ammonium carbonate was used as the leaching agent on the as-calcined samples to remove the weakly bound copper species. The parent and leached catalysts were tested for the preferential oxidation of carbon monoxide (CO-PROX) reaction from 40 to 200 °C in 1%CO/1%O2/50%H2/N2 with a space velocity of 60,000 mL h−1 gcat−1. When the Cu doping amount reached 30 at.%, the stable and constant CO-PROX reactivity, including CO conversion and O2 selectivity, was presented for both parent and ammonium carbonate leached catalysts. The fresh and used samples have been carefully characterized by various techniques such as power X-ray diffraction (XRD), X-ray absorption fine structure (XAFS), transmission electron microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS) and temperature-programmed reduction by hydrogen (H2-TPR). It was confirmed that there are two different types of copper species, i.e. weakly bound CuOx clusters and strongly bound Cu–[Ox]–Ce structure, in both parent and leached catalysts. Furthermore, we have demonstrated that the weakly bound CuOx clusters removed by ammonium carbonate can be recovered by the migration of Cu–[Ox]–Ce species under the reduction or reaction conditions. The strongly bound copper species in CeO2 have been identified to be the reservoir for the active Cu sites for CO-PROX.

合成了在四氧化三铁表面包覆二氧化铈或二氧化钛的铁基复合纳米结构材料,并将其应用于催化氨分解的反应。采用多种表征手段(包括透射电子显微镜、X射线衍射、原位X射线衍射、程序升温还原和N2吸脱附)对反应前和反应后的的催化剂进行了结构表征。相比于纯四氧化三铁催化剂,包覆了二氧化铈或二氧化钛的铁基复合纳米催化剂在24,000 cm3 g cat −1 h−1的空速下650°C时氨的转化率接近100 %,而且在600 °C 60 h 的稳定性测试也具有较好的稳定性。结果表明,二氧化铈或二氧化钛的加入对改进氨分解的催化活性和提高热稳定性起到了关键作用。

Co–Al nanocomposite materials as active and stable catalysts for ammonia decomposition have been synthesized by a one-pot evaporation-induced self-assembly method. The catalysts were characterized by various techniques including powder X-ray diffraction (XRD), X-ray absorption fine structure (XAFS), X-ray photoelectron spectroscopy (XPS), N2 adsorption/desorption, and transmission/scanning electron microscopy (TEM/SEM). Especially, in situ XRD under catalytic reaction conditions was performed, and metallic Co with a cubic structure was identified to be most probably the active crystalline phase for the decomposition of ammonia; also, contribution of CoO to the catalytic activity cannot be excluded. Most importantly, the introduction of alumina can significantly suppress the agglomeration of the active metallic Co phase and thus maintain the high activity of the cobalt catalyst.

Copper-ceria is one of the very active catalysts for the preferential oxidation of carbon monoxide (CO-PROX) reaction, which is also a typical system in which the complexity of copper chemistry is clearly exhibited. In the present manuscript, copper–ceria catalysts with different Cu contents up to 20 wt % supported on CeO2 nanorods were synthesized by a deposition–precipitation (DP) method. The as-prepared samples were characterized by various structural and textural detections including X-ray diffraction (XRD), Vis-Raman, transmission electron microscopy (TEM), ex situ/in situ X-ray absorption fine structure (XAFS), and temperature-programmed reduction by hydrogen (H2-TPR). It has been confirmed that the highly dispersed copper oxide (CuOx) clusters, as well as the strong interaction of Cu-[Ox]-Ce structure, were the main copper species deposited onto the ceria surface. No separated copper phase was detected for both preoxidized and prereduced samples with the Cu contents up to 10 wt %. The fresh copper–...

Transition metal (Fe, Co, and Ni) nanoparticles dispersed in an alumina matrix as catalysts for NH3 decomposition have been synthesized by a facile co-precipitation method. The fresh and used catalysts were characterized by various techniques including powder X-ray diffraction (XRD), N2 adsorption/desorption, and transmission electron microscopy (TEM). Also, temperature-programmed reduction by hydrogen (H2-TPR) combining in situ XRD was performed to investigate the reducibility of the studied catalysts. For the ammonia decomposition reaction, 88% conversion of ammonia can be realized at the reaction temperature as low as 600 °C using a space velocity of 72 000 cm3 gcat−1 h−1 NH3 during a long term (72 h) catalysis test without any observable deactivation. The small amount of alumina (low to 10 at%) can act as the matrix in which the catalytically active transition metal nanoparticles were stabilized. Thus, the agglomeration of active transition metals under reaction conditions was significantly suppressed and the high activity of catalysts was maintained.

High-surface-area Co-SiO

Carboxylesterases (CarEs) are involved in metabolic detoxification of dietary and environmental xenobiotics in insects. However, owing to the complexity of the protein family, the involvement of CarEs in insecticide metabolism in Plutella xylostella has not been fully elucidated. This study aimed to characterise two CarE genes and assess their potential roles in response to chlorpyrifos in P. xylostella.Synergistic tests showed that triphenyl phosphate decreased the resistance of the third-instar larvae to chlorpyrifos. The treatment of the third-instar larvae with chlorpyrifos at the LCRNAi knockdown of Pxae18 and Pxae28 significantly inhibited detoxification ability and increased the mortality in P. xylostella. The results indicate that these two CarE genes play important roles in the detoxification of chlorpyrifos in P. xylostella. © 2016 Society of Chemical Industry.

To compare PPD conversion with γ-interferon release assay (IGRA) in determining the newly Mycobacterium tuberculosis (MTB) infection during a TB outbreak.The 505 subjects exposed to a TB outbreak were divided into 3 groups based upon the induration diameters of PPD before the outbreak. The changes of PPD induration diameters were observed in different groups, and correlation between PPD conversion or IGRA and exposure levels were analyzed by logistic regression.In subjects with the highest exposure level, the increase in induration of PPD was (12 ± 5) mm, (7 ± 4) mm, and (5 ± 3) mm respectively among the previous PPD5 mm, 5 -10 mm, and ≥ 10 mm groups, the difference being significant among groups, χ(2) = 43.12, P0.01. Using logistic regression analysis, PPD conversion was related to the exposure level (OR = 4.70, P0.05) only in the PPD5 mm group, while IGRA positivity was closely related to the exposure levels in all 3 groups (OR values were 2.16 - 3.60, P0.05). In the high exposure group, the subjects with IGRA positivity combined with PPD conversion rate was 26.1% (31/119), and the subjects with IGRA positivity but no PPD conversion rate was 39.5% (47/119), while in the low exposure group the results were 6.5% (12/185) and 16.8% (31/185) respectively, the difference being significant (χ(2) = 22.82 and 19.63, P0.01). After 1 year of follow-up, the reversion rate of the subjects with IGRA positivity was 48.1% (91/189), while the mean increase value of PPD was (1.1 ± 4.0) mm.IGRA is superior to PPD conversion in the diagnosis of tuberculosis infection, and more valuable in the detection of newly infected cases.