A High-Density Genetic Linkage Map and QTL Mapping for Sex in Black Tiger Shrimp (Penaeus monodon)

The black tiger shrimp, Penaeus monodon, is important in both fishery and aquaculture and is the second-most widely cultured shrimp species in the world. However, the current strains cannot meet the market needs in various cultural environments, and the genome resources for P. monodon are still lacking. Restriction-site associated DNA sequencing (RADseq) has been widely used in genetic linkage map construction and in quantitative trait loci (QTL) mapping. We constructed a high-density genetic linkage map with RADseq in a full-sib family. This map contained 6524 single nucleotide polymorphisms (SNPs) and 2208 unique loci. The total length was 3275.4 cM, and the genetic distance was estimated to be 1.1 Mb/cM. The sex trait is a dichotomous phenotype, and the same interval was detected as a QTL using QTL mapping and genome-wide association analysis. The most significant locus explained 77.4% of the phenotype variance. The sex locus was speculated to be the same in this species based on the sequence alignments in Mozambique, India, and Hawaii populations. The constructed genetic linkage map provided a valuable resource for QTL mapping, genome assembly, and genome comparison for shrimp. The demonstrated common sex locus is a step closer to locating the underlying gene

The Transcriptional Factor PPARαb Positively Regulates Elovl5 Elongase in Golden Pompano Trachinotus ovatus (Linnaeus 1758)

The nuclear peroxisome proliferator-activated receptors (PPARs) regulate the transcription of elongases of very long-chain fatty acids (Elovl), which are involved in polyunsaturated fatty acid (PUFA) biosynthesis in mammals. In the present study, we first characterized the function of Elovl5 elongase in Trachinotus ovatus. The functional study showed that ToElovl5 displayed high elongation activity toward C18 and C20 PUFA. To investigate whether PPARαb was a regulator of Elovl5, we also reported the sequence of T. ovatus PPARαb (ToPPARαb). The open reading frame (ORF) sequence encoded 469 amino acids possessing four typical characteristic domains, including an N-terminal hypervariable region, a DNA-binding domain (DBD), a flexible hinge domain and a ligand-binding domain (LBD). Thirdly, promoter activity experiments showed that the region from PGL3-basic-Elovl5-5 (-146 bp to +459 bp) was defined as the core promoter by progressive deletion mutation of Elovl5. Moreover, PPARαb overexpression led to a clear time-dependent enhancement of ToElovl5 promoter expression in HEK 293T cells. Fourth, the agonist of PPARαb prominently increased PPARαb and Elovl5 expression, while PPARαb depletion by RNAi or an inhibitor was correlated with a significant reduction of Elovl5 transcription in T. ovatus caudal fin cells (TOCF). In conclusion, the present study provides the first evidence of the positive regulation of Elovl5 transcription by PPARαb and contributes to a better understanding of the transcriptional mechanism of PPARαb in fish

Functional roles of circular RNAs in lung injury

Lung injury leads to respiratory dysfunction, low quality of life, and even life-threatening conditions. Circular RNAs (circRNAs) are endogenous RNAs produced by selective RNA splicing. Studies have reported their involvement in the progression of lung injury. Understanding the roles of circRNAs in lung injury may aid in elucidating the underlying mechanisms and provide new therapeutic targets. Thus, in this review, we aimed to summarize and discuss the characteristics and biological functions of circRNAs, and their roles in lung injury from existing research, to provide a theoretical basis for the use of circRNAs as a diagnostic and therapeutic target for lung injury

Characterization, functional analysis and antibacterial activities of theromacin from the Akoya pearl oyster Pinctada fucata

The Akoya Pearl oyster Pinctada fucata is distributed over the coastal area of South China and is the most popular farming shellfish for seawater pearl production. Antimicrobial peptides (AMPs) could inhibit or kill pathogenic microorganisms. Theromacin has been proven to be an antimicrobial peptide, which plays an essential role in the body's immune system. The AMP gene to be identified was encoding theromacin in the pearl oyster Pinctada fucata (PoAP). The full-length PoAP cDNA contains 522 bp and consists of a 5’-UTR of 6 bp, an unusually long 3’-UTR of 749 bp, and an open reading frame (ORF) of 375 bp that encodes a 124 amino acid peptide with a molecular weight of 13.67 kDa and the theoretical isoelectric point of 9.25. Homology analysis of the deduced amino acid sequence of the PoAP with other known theromacin sequences by MatGAT software revealed that the PoAP shared 29.0%-46.8% similarity to the other known theromacin sequences. Signal P-N program showed that PoAP contains 33 amino acid signal peptides and a mature peptide located at amino acids 34-124; the mature peptide contains 12 cysteine residues and 13 alkaline amino acid residues with a molecular weight of 13.67 kDa and the theoretical isoelectric point of 9.25. The tempered program suggests that PoAP is a membrane protein with one transmembrane helix between amino acids 13 and 34. The PoAP gene was linked into prokaryotic vector pET-32α, and the PoAP fusion protein with 31 kDa molecular mass was successfully expressed in Escherichia coli BL21. Using His-Bind Purification Kit Protocol purifies the antimicrobial peptides recombinant protein and compares the bacteriolysis effect on Gram-positive and Gram-negative bacteria using the purified protein. The results show that PoAP proteins had a bacteriolysis effect on the Gram-negative bacteria but on Gram-positive organisms. The antibacterial peptides theromacin seem to play a crucial antibacterial function in the immune responses of pearl oysters

A Closed-Form Phase Noise Solution For An Ideal Lc Oscillator

A closed-form impulse response is derived for a parallel RLC circuit. Modeling thermal noise as current impulse injections to the circuit, the phase and amplitude noise of an ideal LC oscillator are obtained using the closed-form RLC impulse response. Furthermore, the Taylor series expansion method is used to obtain a linearized phase noise model. For this linearized model, the phase change function obtained from our solution verifies the impulse sensitivity function (ISF) from previously published results. Meanwhile, since this close-form solution is non-linear in its original form, the proposed solution can potentially facilitate a non-linear power spectrum analysis of the phase noise in an ideal LC oscillator

Effect of initial crown on shape of hot rolled strip

Based on the influence coefficient method, the effect of entry strip crown on the shape of hot rolled strip was analyzed using the software of roll elastic deformation simulation. According to the practical condition of a domestic hot rolled strip plant, the unit strip crown change from the first stand to the last stand was calculated when the entry crown of hot strip varies. The calculated result shows that the entry strip crown does not significantly affect the target strip crown at the exit of the last finishing stand in respect to a fixed strip shape control reference (such as bending force). The calculation was analyzed, and the research is helpful in modeling strip shape setup and shape control

Capabilities of stochastic response surface method and response surface method in reliability analysis

The stochastic response surface method (SRSM) and the response surface method (RSM) are often used for structural reliability analysis, especially for reliability problems with implicit performance functions. This paper aims to compare these two methods in terms of fitting the performance function, accuracy and efficiency in estimating probability of failure as well as statistical moments of system output response. The computational procedures of two response surface methods are briefly introduced first. Then their capabilities are demonstrated and compared in detail through two examples. The results indicate that the probability of failure mainly reflects the accuracy of the response surface function (RSF) fitting the performance function in the vicinity of the design point, while the statistical moments of system output response reflect the accuracy of the RSF fitting the performance function in the entire space. In addition, the performance function can be well fitted by the SRSM with an optimal order polynomial chaos expansion both in the entire physical and in the independent standard normal spaces. However, it can be only well fitted by the RSM in the vicinity of the design point. For reliability problems involving random variables with approximate normal distributions, such as normal, lognormal, and Gumbel Max distributions, both the probability of failure and statistical moments of system output response can be accurately estimated by the SRSM, whereas the RSM can only produce the probability of failure with a reasonable accuracy

Slope reliability analysis considering spatially variable shear strength parameters using a non-intrusive stochastic finite element method

This paper proposes a non-intrusive stochastic finite element method for slope reliability analysis considering spatially variable shear strength parameters. The two-dimensional spatial variation in the shear strength parameters is modeled by cross-correlated non-Gaussian random fields, which are discretized by the Karhunen-Loeve expansion. The procedure for a non-intrusive stochastic finite element method is presented. Two illustrative examples are investigated to demonstrate the capacity and validity of the proposed method. The proposed non-intrusive stochastic finite element method does not require the user to modify existing deterministic finite element codes, which provides a practical tool for analyzing slope reliability problems that require complex finite element analysis. It can also produce satisfactory results for low failure risk corresponding to most practical cases. The non-intrusive stochastic finite element method can efficiently evaluate the slope reliability considering spatially variable shear strength parameters, which is much more efficient than the Latin hypercube sampling (LHS) method. Ignoring spatial variability of shear strength parameters will result in unconservative estimates of the probability of slope failure if the coefficients of variation of the shear strength parameters exceed a critical value or the factor of slope safety is relatively low. The critical coefficient of variation of shear strength parameters increases with the factor of slope safety. (C) 2013 Elsevier B.V. All rights reserved