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Species of the family Prosthogonimidae are considered the most pathogenic trematodes of poultry and wild birds worldwide, causing heavy economic losses in many countries. Prosthogonimosis was a common parasitic disease of Grus japonensis (Müller, 1776) which caused inflammation of the cloaca and bursa of Fabricius and even death. Morphological identifications of Prosthogonimus species are easily confusing; therefore, molecular characterization is used for discrimination. The present study was conducted to identify Prosthogonimus species at Zhalong National Nature Reserve, northeast of China. Considering the morphological variability and wide host range of individual Prosthogonimus species, a combination of both morphological and molecular analyses is indispensable for the valid identification of this parasite and the internal transcribed spacer (ITS) region was amplified for the sequence analysis and phylogenetic analysis. The results of molecular analysis together with phylogenetic reconstruction indicated that the Prosthogonimus pellucidus (von Linstow, 1873) in this study form a single cluster with P. pellucidus, revealing potentially high diversity within the genus Prosthogonimus. Classification of Prosthogonimus species seems to be unrelated to the host and may be related to geographical location. These data provide a significant resource of molecular markers for studying the taxonomy, population genetics, and systematics of Prosthogonimidae.

Austenite reversion has been widely used in the traditional heat treatment of steels, and recently, it has been used in the fabrication of advanced high-strength steels. The microstructure of reverted austenite significantly influences the final microstructure and properties of steel; thus, it is crucial to understand the formation of globular austenite to accurately grasp its reversion behavior. In this paper, an Fe–2.5Mn–1.5Si–0.35C alloy was chosen as the research object, and the evolution of intragranular globular austenite and finally transformed austenite grain size were studied under different pre-tempering conditions using a metallographic optical microscope, scanning electron microscope, and electron backscatter diffraction. It was found that as the pre-tempering temperature was increased from 350 ℃ to 650 ℃, the volume fraction of intragranular globular austenite first increased and then rapidly decreased. At the pre-tempering temperature of 400 ℃, the volume fraction of intragranular globular austenite initially increased and remained stable thereafter, when the pre-tempering duration was increased from 1 to 10 h. Fine cementite particles were primarily formed immediately before the reversion in the non-tempered or low-temperature pre-tempered initial structures. This provided less effective nucleation sites for the formation of intragranular globular austenite. Therefore, lesser intragranular globular austenite grains were formed, thereby resulting in relatively coarse finally transformed austenite grains after reversion. The cementite particles were gradually coarsened as the pre-tempering temperature was increased to 550 ℃, thereby increasing the number of effective nucleation sites for the formation of intragranular globular austenite. Conversely, when the martensite samples were pre-tempered at a high temperature of 650 ℃, Mn is seriously enriched into the cementite particles before the reversion, largely reducing the driving force for reversion. This resulted in the growth of intragranular globular austenite under the partitioning local equilibrium mode, with a slow growth rate, resulting in a low volume fraction. Therefore pre-tempering can effectively promote the formation of intragranular globular austenite. Owing to its multiple orientations, increased intragranular globular austenite formation resulted in significantly refined austenite grains after reversion. This study provided a new strategy to regulate the formation of intragranular globular austenite and finally transformed austenite grain size by controlling the size and composition of cementite particles through pre-tempering without changing the chemical composition of the steel.

The bed structure of high-grade large-scale CNC machine tools is crucial for maintaining their long-term service accuracy. This study focused on the key casting process of large nodular cast iron beds. AnyCasting software was employed to simulate and analyze the casting scheme, and then the mold filling and solidification processes were proposed based on the simulation results. The proposed casting scheme indicates that the designed gating system exhibited excellent filling capability. The dual sprue ceramic pipe bottom pouring technique, in conjunction with the chills, not only improved casting efficiency but also met the requirements of sequential solidification design. The castings possessed a dense microstructure characterized by uniform and stable phase composition, primarily comprising lamellar pearlite, with ≤0.5% of phosphorus eutectic and cementite. Furthermore, the microstructure of these materials displayed favorable graphite morphology with a spheroidization rate exceeding 85% and spheroidization grade of 2–3. This study has important academic and application value for the casting process of producing low-stress, high-grade CNC machine tool bed cast iron materials.

Tetrameres grusi is a significant parasitic nematode of cranes that is classified into suborder Spirurina. However, for more than a century, this classification has been controversial. Mitochondrial genomes are valuable resources for parasite taxonomy, population genetics and systematics studies. Here, the mitochondrial genome of T. grusi was determined and subsequently compared with those from Spirurina species using concatenated datasets of amino acid sequences predicted from mitochondrial protein-coding genes. The complete mitochondrial genome of T. grusi is circular with 13,709 bp, and it contains 12 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and one non-coding region. All of the protein-coding genes are transcribed in the same direction. There were 18 intergenic spacers of 1–44 bp, and six locations with gene overlaps, ranging from 1 bp to 28 bp, in the mitochondrial genome of T. grusi. The AT content of this mitochondrial genome was 71.56%. This was similar to mitochondrial genomes of other Spirurina species, which also exhibited strong AT content bias, not only in the nucleotide composition but also in codon usage. The sequenced mitogenomes of the 25 Spirurina nematodes showed three classes of gene arrangements based on the 12 protein-coding genes, and the gene arrangement of the T. grusi mitochondrial genome belonged to the Class I. Phylogenetic analyses using mitochondrial genomes of 25 Spirurina nematodes revealed that T. grusi (Habronematoidea) was closer to Gongylonema pulchrum (Spiruroidea) than Spirocerca lupi (Thelazioidea). The availability of the complete mitochondrial genome sequence of T. grusi provides new and useful genetic markers for further studies on Spirurina nematodes.

Simple Summary: Species of the family Prosthogonimidae are considered the most pathogenic trematodes of poultry and wild birds worldwide, causing heavy economic losses in many countries. The authors of this study conducted morphological and molecular identification of Prosthogonimus pellucidus. These data provide significant molecular markers for the study of taxonomy, population genetics, and systematics of Prosthogonimidae. Species of the family Prosthogonimidae are considered the most pathogenic trematodes of poultry and wild birds worldwide, causing heavy economic losses in many countries. Prosthogonimosis was a common parasitic disease of Grus japonensis (Müller, 1776) which caused inflammation of the cloaca and bursa of Fabricius and even death. Morphological identifications of Prosthogonimus species are easily confusing; therefore, molecular characterization is used for discrimination. The present study was conducted to identify Prosthogonimus species at Zhalong National Nature Reserve, northeast of China. Considering the morphological variability and wide host range of individual Prosthogonimus species, a combination of both morphological and molecular analyses is indispensable for the valid identification of this parasite and the internal transcribed spacer (ITS) region was amplified for the sequence analysis and phylogenetic analysis. The results of molecular analysis together with phylogenetic reconstruction indicated that the Prosthogonimus pellucidus (von Linstow, 1873) in this study form a single cluster with P. pellucidus, revealing potentially high diversity within the genus Prosthogonimus. Classification of Prosthogonimus species seems to be unrelated to the host and may be related to geographical location. These data provide a significant resource of molecular markers for studying the taxonomy, population genetics, and systematics of Prosthogonimidae. [ABSTRACT FROM AUTHOR]

The Chengjiang Biota is the earliest most diverse animal community from the Cambrian Explosion (~518 million years ago). This biota is shown to have colonized a delta, highlighting the importance of this shallow environment in recording early snapshots of life on Earth.

Traditional plastics, such as polyethylene (PE), polystyrene (PS), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polyurethane (PUR), and other plastic polymers, are difficult to degrade and are gradually accumulated in the environment to cause a serious environmental problem, which is urgently needed to develop novel treatments or control technology. The biodegradation of plastics has gained great attention due to the advantages of green and safe characteristics. Microorganisms play a vital role in the biodegradation of plastics, including environmental microbes (in vitro) and gut microbes of insects (in vivo). Microbial degradation in environmental conditions in vitro is extremely slow for major plastics at degradation rates on the basis of a month or even a year time, but recent discoveries show that the fast biodegradation of specific plastics, such as PS, PE, and PUR, in some invertebrates, especially insects, could be enhanced at rates on basis of hours; the biodegradation in insects is likely to be gut microbial-dependent or synergetic bioreactions in animal digestive systems. This review comprehensively summarizes the latest 7-year (2016–2022) publications on plastic biodegradation by insects and microorganisms, elucidates the mechanism of plastic degradation in insects and environmental microbes, and highlights the cutting-edge perspectives for the potential applications of plastic biodegradation.

The great success of cisplatin as a chemotherapeutic agent considerably increased research efforts in inorganic biochemistry to identify more metallic drugs having the potential of treating lung cancer. Metal coordination centres, which exhibit a wide range of coordination numbers and geometries, various oxidised and reduced states and the inherent ligand properties offer pharmaceutical chemists a plethora of drug structures. Owing to the presence of C=N and C=S bonds in a thiosemicarbazone Schiff base, N and S atoms in its hybrid orbital has lone pair of electrons, which can generate metal complexes with different stabilities with most metal elements under certain conditions. Such ligands and complexes play key roles in the treatment of anti-lung cancer. Research regarding metallic anti-lung cancer has advanced considerably, but there remain several challenges. In this review, we discuss the potential of thiosemicarbazone Schiff base complexes as anti-lung cancer drugs, their anti-cancer activities and the most likely action mechanisms involving the recent families of copper, nickel, platinum, ruthenium and other complexes.

Piezoelectric ceramic, an indispensable micro-nano actuator, has advantages of small size, high sensitivity and strong controllability, which is widely applied in various fields like micro-nano processing, medicine, chemistry and materials. However, its nonlinear and asymmetric hysteresis features directly affect its positioning accuracy. The classical and generalized Prandtl-Ishlinskii models with linear symmetry operators are commonly used to deal with these issues, but they still face difficulties in asymmetric systems. Therefore, a piecewise modified Prandtl-Ishlinskii (PMPI) model is proposed to compensate nonlinear and asymmetric hysteresis in this paper. The new nonlinear operator and piecewise nonlinear envelope function are introduced into the PMPI model. Independent right and left parts are adopted to describe hysteresis increasing and decreasing stages, while the threshold and weight vectors correspond to them. Weight vectors are extended and a new diagonal matrix is constructed for avoiding excessive parameters and computation. Simulations and experiments are shown that the PMPI model has good compensation performance and effectiveness, which has better fitting, higher accuracy, fewer parameters and computation, and can be well applied to the precise nano-positioning systems with less nonlinear and asymmetric errors. [ABSTRACT FROM AUTHOR]