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Agricultural residues, such as lignocellulosic materials (LM), are the most attractive renewable bioenergy sources and are abundantly found in nature. Anaerobic digestion has been extensively studied for the effective utilization of LM for biogas production. Experimental investigation of physiochemical changes that occur during pretreatment is needed for developing mechanistic and effective models that can be employed for the rational design of pretreatment processes. Various-cutting edge pretreatment technologies (physical, chemical and biological) are being tested on the pilot scale. These different pretreatment methods are widely described in this paper, among them, microaerobic pretreatment (MP) has gained attention as a potential pretreatment method for the degradation of LM, which just requires a limited amount of oxygen (or air) supplied directly during the pretreatment step. MP involves microbial communities under mild conditions (temperature and pressure), uses fewer enzymes and less energy for methane production, and is probably the most promising and environmentally friendly technique in the long run. Moreover, it is technically and economically feasible to use microorganisms instead of expensive chemicals, biological enzymes or mechanical equipment. The information provided in this paper, will endow readers with the background knowledge necessary for finding a promising solution to methane production.

During investigations into an outbreak of egg production decline, retarded growth, and even death among ducks in Southeast China, a novel Tembusu virus strain named Tembusu virus Fengxian 2010 (FX2010) was isolated. This virus replicated in embryonated chicken eggs and caused embryo death. In cross-neutralization tests, antiserum to the partial E protein of Tembusu virus Mm1775 strain neutralized FX2010, whereas antiserum to Japanese encephalitis virus did not. FX2010 is an enveloped RNA virus of approximately 45-50 nm in diameter. Sequence analysis of its E and NS5 genes showed that both genes share up to 99.6% nucleotide sequence identity with Baiyangdian virus, and up to 88% nucleotide sequence identity with their counterparts in Tembusu virus. FX2010 was transmitted without mosquito, and caused systemic infection and lesions in experimentally infected ducks. These results indicate that FX2010 and BYD virus are newly emerged Tembusu virus strains that cause an infectious disease in ducks.

Observation of a new type of nanoscale ferroelectric domains, termed as "bubble domains"-laterally confined spheroids of sub-10 nm size with local dipoles self-aligned in a direction opposite to the macroscopic polarization of a surrounding ferroelectric matrix-is reported. The bubble domains appear in ultrathin epitaxial PbZr Ti O /SrTiO /PbZr Ti O ferroelectric sandwich structures due to the interplay between charge and lattice degrees of freedom. The existence of the bubble domains is revealed by high-resolution piezoresponse force microscopy (PFM), and is corroborated by aberration-corrected atomic-resolution scanning transmission electron microscopy mapping of the polarization displacements. An incommensurate phase and symmetry breaking is found within these domains resulting in local polarization rotation and hence impart a mixed Néel-Bloch-like character to the bubble domain walls. PFM hysteresis loops for the bubble domains reveal that they undergo an irreversible phase transition to cylindrical domains under the electric field, accompanied by a transient rise in the electromechanical response. The observations are in agreement with ab-initio-based calculations, which reveal a very narrow window of electrical and elastic parameters that allow the existence of bubble domains. The findings highlight the richness of polar topologies possible in ultrathin ferroelectric structures and bring forward the prospect of emergent functionalities due to topological transitions.

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Anaerobic mono- and co-digestion of kitchen waste (KW), corn stover (CS), and chicken manure (CM) under mesophilic (37 °C) conditions were conducted in batch mode with the aim of investigating the biomethane potential (BMP), biodegradability, methane production performance, and stability of the process. An initial volatile solid concentration of 3 g VS L–1 with a substrate-to-inoculum (S/I) ratio of 0.5 was first tested, and two S/I ratios of 1.5 and 3.0 were evaluated subsequently. The modified Gompertz equation was used to assist in the interpretation of the conclusions. The results showed that BMP and specific methane yields were 725 and 683 mL g–1 VSadded for KW, 470 and 214 mL g–1 VSadded for CS, and 617 and 291 mL g–1 VSadded for CM, respectively. Therefore, KW had the highest biodegradability of 94% as compared with CS (45%) or CM (47%). For KW mono- and co-digestion with CS, CM, or their mixture, methane production performance was better at an S/I ratio of 1.5 than that of 3.0. For CS, CM, and their mixture, S/I ratios of both 1.5 and 3.0 were suitable. A synergistic effect was found in the co-digestion process, which was mainly attributed to a proper carbon-to-nitrogen ratio and the reduced total volatile fatty acids-to-total alkalinity ratio, thus providing better buffering capacity and supporting more microorganisms for efficient digestion.

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