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Understanding the mechanisms driving parasite distributions is not only important for understanding ecosystem functioning, but also crucial for disease control. Previous studies have documented the important roles of host sex, host body size, host behavioral trait (such as boldness and trappability), and seasonality in shaping parasite load. However, few studies have simultaneously assessed the roles of these factors, as well as their interactions. In spring and summer of 2021, we conducted live trapping in Hohhot, China, to collect ectoparasites on Daurian ground squirrel (Spermophilus dauricus), a small rodent widely distributed in East Asian grassland. We then used generalized linear models to explore the effects of several biological factors (sex, body weight, trappability, and reproductive status) and seasonality on the abundance of ticks and fleas in S. dauricus. Significant but inconsistent seasonal effects were observed: tick load was significantly greater in summer than in spring, while flea load was greater in spring than in summer. Seasons also significantly interacted with host trappability and body weight to affect tick abundance. Our results highlight the importance of considering seasonal changes in parasitism, as well as interactions between season and host biological traits in shaping parasite distributions. [Display omitted] • Both fleas and ticks show seasonal changes in abundance but in different directions. • Relationship between host body weight and tick load changes between seasons. • Effect of trappability on tick abundance depends on season. [ABSTRACT FROM AUTHOR]

Several recent studies investigated the role of the miR-29 family in muscle development. However, only a few studies focused on chicken skeletal muscle. In the present study, cell cycle, 5-ethynyl-2'-deoxyuridine (EdU), cell counting kit-8 (CCK-8), and other assays indicated that miR-29b-1-5p can inhibit the proliferation of chicken primary myoblasts (CPMs); the western blot assay and immunofluorescence detection of MYHC demonstrated that miR-29b-1-5p can promote the differentiation of myoblasts. The functional enrichment analysis revealed that the target genes of miR-29b-1-5p may be involved in muscle tissue development, muscle organ development, and striated muscle tissue development, which are biological processes related to muscle development. The correlation analysis showed that these 6 genes, that is, ankyrin repeat domain 9 ( ANKRD9 ), lactate dehydrogenase A ( LDHA ), transcription factor 12 ( TCF12 ), FAT atypical cadherin 1 ( FAT1 ), lin-9 homolog ( LIN9 ), and integrin beta 3 binding protein ( ITGB3BP ), can be used as effective candidate target genes of miR-29b-1-5p. Moreover, miR-29b-1-5p inhibits the expression of ANKRD9 by directly binding the 3′UTR of ANKRD9. Overall, these data indicate that miR-29b-1-5p inhibits the proliferation of primary chicken myoblasts, stimulates their differentiation, and is involved in the process of muscle development and that its effective target gene is ANKRD9. This study identified the molecular mechanism of miR-29b-1-5p in chicken muscle development. [ABSTRACT FROM AUTHOR]

Abstract: The scatter of the variable load spectra is considered separately from the scatter of the aircraft structure to assess the safe-life of a fleet. Suppose the fatigue life under the specified load spectrum follows the log-normal distribution with a constant coefficient of variation, and the load spectra damage follows the log-normal distribution with a constant standard deviation, the theoretical distribution function of fatigue life of the fleet that accounts for the variability of the structure and the load spectrum is derived with the conditional probability model. Monte-Carlo simulation shows that the distribution of the fleet fatigue life can be described approximately by a log-normal distribution function, and the log expectation is the log mean life under variable load spectra and the variation equals the sum of the structural variation and the load spectra variation. The scatter factor method is then adopted to assess the safe-life. The scatter factor of the individual aircraft with definite load spectrum, as well as the scatter factor of the in-service fleet that takes the actual load scatter into consideration are listed. [Copyright &y& Elsevier]

Highlights: [•] Variability of load spectrum of a fleet is analyzed. [•] Fatigue tests are conducted to test the variability of load spectrum. [•] Load spectrum damage follows a lognormal distribution. [ABSTRACT FROM AUTHOR]

Abstract: The fatigue life scatter of an aircraft fleet includes the variabilities of the material, structural property and the load spectrum. With more and more knowledge on the load variation, the 90% severe durability load spectrum has been proposed in JSSG-2006 of USA and used in the service life assessment program for several aircraft types. However, what is the life reliability of a fleet under this 90% severe spectrum and how severe the load spectrum should be are still perplexing. This paper would discuss the fleet life reliability under the severe load spectrum. Assuming both the fatigue life under a specified load spectrum and the load spectrum damage of a fleet follow the log-normal distribution and the standard deviations are σS and σL respectively, the fleet life was deduced to follow a log-normal distribution, the log mean life is unchanged and the variation is the sum of and . The expression of the fleet life reliability P was also deduced and it is influenced by the σS and σL . The typical values of P were calculated for the cited σS and σL . To ensure the fleet service safety under the 90% load spectrum, the requirement on the severity degree, PL , which is also the load reliability, was discussed. It showed that the severity of the severe spectrum is not a constant. If the 90% damage spectrum was used, the standard deviation of load spectrum damage should be controlled less than 0.14 at least. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) hierarchical cabbage-like carbonaceous materials (Fe/CCMs- X , X means treating temperature) have been successfully prepared employing combinatorial processes of cobalt-assisted hydrothermal carbonization (HTC) of furfural and subsequent iron salt impregnation and thermal treatment. This new absorbent was characterized using powder X-ray diffraction (XRD), N 2 adsorption–desorption isotherms, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM) techniques. The maximum reflection loss (RL) of Fe/CCMs-500 reached −22.9 dB, and the effective absorption bandwidth (RL ⩽ −10 dB) was 4.32 GHz (7.76–9.84 GHz and 11.20–13.44 GHz) corresponding to an absorber thickness of 2.5 mm, a low loading amount of iron (6.83%) component and high carbon content (69.8%), clearly demonstrating its wide absorption frequency range and strong absorption ability. It is thus believed that the newly synthesized Fe/CCMs-500 can serve as light-weight electromagnetic wave absorbent and can be potentially used in practice. [ABSTRACT FROM AUTHOR]