Estimation of a novel method to produce bio-oil from sewage sludge by microwave pyrolysis with the consideration of efficiency and safety

This paper presented a feasible method to produce bio-oil from sewage sludge by microwave pyrolysis. The results showed that oils derived under 400 W obtained an attractive yield (49.8 wt.%) with favorable characteristics such as high calorific value (35.0 MJ/kg), low density (929 kg/m3) and preferable chemical composition (29.5 wt.% of monoaromatics). A model to study the relationship between microwave power and mass balance of product fractions was developed, and the results indicated that the power range of the highest transforming efficiency for organics in sludge into oils was 400-600 W, the subsequent increase of power to the range of 600-800 W favored gases formation at the expense of oils, and increase of power to above 800 W led to the conversion of solids into gases, while oils remained unchanged. The analysis of sulfur and nitrogen compounds in oils showed that bio-oil should be extracted before being used as fuel.     

Light and Electron Microscopy Studies on the Infection of a Wild‐type and Metalaxyl‐resistant Isolate of Phytophthora sojae in Soybean Hypocotyls

Resistance of soybean cultivars, depending on single dominant genes to Phytophthora sojae, may easily be overcome by emerging new virulent races. Light microscopy (LM) and electron microscopy (EM) were used to study the infection process of the wild‐type isolate Ps411 and metalaxyl‐resistant mutant Ps411‐M of P. sojae in hypocotyls of soybean seedlings grown from untreated and metalaxyl‐treated seeds. The isolate Ps411‐M of P. sojae exhibited a high degree of resistance to metalaxyl compared to Ps411. The pathogenic fitness of Ps411‐M in hypocotyls of soybean seedlings was lower compared to Ps411. LM observations showed distinct differences in the infection process of both isolates in hypocotyls of treated soybean seedlings. EM studies revealed differences in the prepenetration stage between Ps411 and Ps411‐M on hypocotyls grown from seeds treated with 0.02% metalaxyl until the whole seed surface coated. The number of infection sites was markedly reduced and few hyphae continued to spread. Numerous ultrastructural alterations in hyphae were observed in treated hypocotyls infected with Ps411, including pronounced thickening of hyphal cell walls and encasement of haustorium‐like bodies; electron‐dense material was deposited in host cell walls in contact with hyphal cells. Neither the prepenetration process nor penetration or spread of hyphae in the hypocotyls of the resistant isolate was affected in treated compared to non‐treated tissue. While in treated hypocotyls infected with the wild‐type isolate, host defence reactions were induced, no such reactions were detected in treated hypocotyls infected with the resistant isolate. Hypocotyls from metalaxyl‐treated seeds infected with the wild‐type isolate resembled an incompatible interaction, whereas during infection with the metalaxyl‐resistant mutant, the compatible interaction was not changed.     

Arabidopsis class I KNOTTED-like homeobox proteins act downstream in the IDA-HAE/HSL2 floral abscission signaling pathway

Floral organ abscission in Arabidopsis thaliana is regulated by the putative ligand-receptor system comprising the signaling peptide INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) and the two receptor-like kinases HAESA and HAESA-LIKE2. The IDA signaling pathway presumably activates a MITOGEN-ACTIVATED PROTEIN KINASE (MAPK) cascade to induce separation between abscission zone (AZ) cells. Misexpression of IDA effectuates precocious floral abscission and ectopic cell separation in latent AZ cell regions, which suggests that negative regulators are in place to prevent unrestricted and untimely AZ cell separation. Through a screen for mutations that restore floral organ abscission in ida mutants, we identified three new mutant alleles of the KNOTTED-LIKE HOMEOBOX gene BREVIPEDICELLUS (BP)/KNOTTED-LIKE FROM ARABIDOPSIS THALIANA1 (KNAT1). Here, we show that bp mutants, in addition to shedding their floral organs prematurely, have phenotypic commonalities with plants misexpressing IDA, such as enlarged AZ cells. We propose that BP/KNAT1 inhibits floral organ cell separation by restricting AZ cell size and number and put forward a model whereby IDA signaling suppresses BP/KNAT1, which in turn allows KNAT2 and KNAT6 to induce floral organ abscission.     

Effect of different iron loads on serum and tissue biochemical parameters and liver hepcidin mRNA abundance of neonatal piglets

Iron (Fe) is an essential and important trace element for animals. In order to study its metabolism and relationship with hepcidin, piglet models of Fe-deficiency and Fe-overload were established by intramuscular injection with different doses of Fe-dextran (150 mg Fe/ml) within 1 week of age. Twelve piglets were divided into three groups of four animals: deficiency, regular and overload group, receiving 0 ml, 1 ml and 6 ml Fe-dextran, respectively. The piglets were euthanised at the age of 7 days for analysis. The results showed that the Fe-concentrations in liver, spleen and serum of piglets in the overload group were higher than in the regular and deficiency groups (p < 0.05). In the overload group, several serum biochemical parameters, e.g. globulin, total bilirubin, total cholesterol, high density lipoprotein (HDL), malondialdehyde, glutathione peroxidase (GPx), peroxidase and xanthine oxidase were higher, while alkaline phosphatase (AKP) and triglycerides were lower, compared with the regular group (p < 0.05). The serum concentrations of AKP, total bilirubin and peroxidase in the deficiency group were lower, while HDL and GPx were higher, compared with the regular group (p < 0.05). Hepcidin mRNA abundance was 131 times lower in the liver of piglets with Fe-deficiency, and 7 times higher in the overloaded group than that in the regular group (p < 0.05). In conclusion, Fe-overload and deficiency would influence Fe-metabolism, serum biochemical indexes, oxidation state and hepcidin mRNA abundance in piglet liver.     

Resting-state brain organization revealed by functional covariance networks

Background

Brain network studies using techniques of intrinsic connectivity network based on fMRI time series (TS-ICN) and structural covariance network (SCN) have mapped out functional and structural organization of human brain at respective time scales. However, there lacks a meso-time-scale network to bridge the ICN and SCN and get insights of brain functional organization.

Methodology and Principal Findings

We proposed a functional covariance network (FCN) method by measuring the covariance of amplitude of low-frequency fluctuations (ALFF) in BOLD signals across subjects, and compared the patterns of ALFF-FCNs with the TS-ICNs and SCNs by mapping the brain networks of default network, task-positive network and sensory networks. We demonstrated large overlap among FCNs, ICNs and SCNs and modular nature in FCNs and ICNs by using conjunctional analysis. Most interestingly, FCN analysis showed a network dichotomy consisting of anti-correlated high-level cognitive system and low-level perceptive system, which is a novel finding different from the ICN dichotomy consisting of the default-mode network and the task-positive network.

Conclusion

The current study proposed an ALFF-FCN approach to measure the interregional correlation of brain activity responding to short periods of state, and revealed novel organization patterns of resting-state brain activity from an intermediate time scale.