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1.
Theriogenology ; 221: 9-17, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38521007

RESUMO

Semen cryopreservation represents a promising technology utilized for preserving high-quality chicken varieties in husbandry practices. However, the efficacy of this methodology is significantly impeded by the diminished quality of sperm. Metabolites, as the end products of metabolic reactions, serve as indicators of biological processes and offer insights into physiological conditions. In this study, we investigaged the sperm quality and alteration in metabolic profiles during the cryopreservation of Longyou Partridge Chicken semen. Following artificial semen collection, four groups of semen samples were established based on four points of the cryopreservation process (Ⅰ, fresh semen; Ⅱ, semen added extender and chilled at 4 °C for 30 min; Ⅲ, semen added cryoprotectants; Ⅳ, semen gradient freezed and stored in liquid nitrogen). Semen cryopreservation has a negative effect on the percentage of sperm in a straight-line trajectory (LIN), has no significant effect on total motile sperms (TM) or the proportion of sperm with typical morphology (NM). Metabolites were identified using LC-MS technique and analyses including Principal Component Analysis (PCA), Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA), Univariate statistical analysis, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database were employed to identify metabolites. A total of 2471 metabolites had been identified, with the majority of the list being made up of amino acids and their metabolites as well as benzene and substituted derivatives. Group II exhibits 882 metabolites with significantly elevated abundance relative to Group I, alongside 37 metabolites displaying decreased abundance. In Group III, 836 metabolites demonstrate notably augmented abundance compared to Group II, while 87 metabolites exhibit reduced abundance. Furthermore, Group IV showcases 513 metabolites with markedly heightened abundance in comparison to Group III, and 396 metabolites with decreased abundance. Specific metabolites such as 5-Hydroxylysine, Phosphocholine, and alpha-d-glucose-6-phosphate exhibited a progressive decline during the cryopreservation process, correlating with either dilution and chilling, cryoprotectant addition, or freezing. In conclusion, our investigation systematically examined the changes of seminal metabolome and sperm quality throughout the cryopreservation process of rooster semen.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Animais , Sêmen/fisiologia , Galinhas/fisiologia , Motilidade dos Espermatozoides , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Criopreservação/veterinária , Criopreservação/métodos , Espermatozoides/fisiologia , Análise do Sêmen/veterinária , Crioprotetores/farmacologia , Crioprotetores/metabolismo
2.
Opt Express ; 29(2): 1109-1124, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33726333

RESUMO

The elastic modes of a general circular thin plate (EMCTP), reflecting the natural deformation of the resonance, are applied to the diffraction theory of the optical aberrations in this paper. Our work has shown that the mode shapes of the EMCTP resemble those of the Zernike polynomials. As an application example, the compensations of some low order aberrations of the 2.5 m-wide field survey telescope (WFST) have been performed with the EMCTP. Moreover, a quantitative comparative study of the active optics corrections for the EMCTP and the Zernike polynomials is presented in the numerical analysis. The quantitative analysis results have demonstrated that the efficiency of the EMCTP is superior to the standard Zernike polynomials as well as the annular Zernike polynomials.

3.
Opt Express ; 27(2): 404-415, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30696127

RESUMO

In this paper, an elastic mode method of deformable mirror is proposed to decompose arbitrary wave-front errors of adaptive optics system. The elastic modes are derived with an analytical method of linear piezoelectricity based on a bimorph piezoelectric deformable mirror (BPDM), and the three-dimensional formulas of elastic modes are presented. Here a BPDM with an aperture of 165 mm as an example is numerically studied. Two different kinds of dynamic boundary conditions are considered, and the dependence of the elastic modes aberrations upon the orders and rotational symmetries is evaluated. Besides, a comparative study for elastic mode and Zernike polynomials is presented in the numerical analysis. The results have demonstrated that the elastic mode method can be not only used instead of Zernike polynomials, but also more effective to decompose arbitrary wave-front errors of a deformable mirror. Furthermore, finite element analysis method is used to validate the analytic method. The conclusions have shown reasonably consistent results between the two methods.

4.
Publ Astron Soc Pac ; 131(1001)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33505044

RESUMO

We present the design for the first narrowband filter NB964 for the Dark Energy Camera (DECam), which is operated on the 4m Blanco Telescope at the Cerro Tololo Inter-American Observatory. The NB964 filter profile is essentially defined by maximizing the power of searching for Lyman alpha emitting galaxies (LAEs) in the epoch of reionization, with the consideration of the night sky background in the near-infrared and the DECam quantum efficiency. The NB964 filter was manufactured by Materion in 2015. It has a central wavelength of 964.2 nm and a full width at half maximum (FWHM) of 9.2 nm. An NB964 survey named LAGER (Lyman Alpha Galaxies in the Epoch of Reionization) has been ongoing since December 2015. Here we report results of lab tests, on-site tests and observations with the NB964 filter. The excellent performances of this filter ensure that the LAGER project is able to detect LAEs at z ~ 7 with a high efficiency.

5.
Appl Opt ; 55(31): 8763-8769, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27828273

RESUMO

We have proposed a multi-variable H-ß optimization approach (MHOA). Compared with the conventional push-pull-shear lateral support optimization (CPLSO), which has only one design variable, ß, MHOA adds another design variable, H, which is the support position height. By contrast, the support position height of CPLSO is usually fixed at mid-thickness, Hm (or at H0, the height of the center of gravity for the mirror), on the outer rim of the mirror blank. In addition, hybrid optimization with the sub-problem approximation method and first order method is also applied in MHOA. To verify the feasibility and the advancement, the optimization of the lateral support of the 2.5 m-wide field survey telescope (WFST) is performed with MHOA in this paper. Three designs with different supporting points, including 18 supporting points, 24 supporting points, and 36 supporting points, are obtained, and the residual half path length errors are 23.71 nm, 19.60 nm, and 17.79 nm, respectively. Furthermore, other things being equal, CPLSO with H=H0 as well as CPLSO with H=Hm are used separately to validate the H-ß design idea quantitatively. The results have suggested that limiting the value of the residual half path length error, obtained by MHOA, has improved almost 20 nm compared to that of CPLSO with H=H0, and almost 10 nm compared with that of CPLSO with H=Hm.

6.
Nat Commun ; 6: 7323, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26065563

RESUMO

Long-duration (>2 s) γ-ray bursts that are believed to originate from the death of massive stars are expected to be accompanied by supernovae. GRB 060614, that lasted 102 s, lacks a supernova-like emission down to very stringent limits and its physical origin is still debated. Here we report the discovery of near-infrared bump that is significantly above the regular decaying afterglow. This red bump is inconsistent with even the weakest known supernova. However, it can arise from a Li-Paczynski macronova--the radioactive decay of debris following a compact binary merger. If this interpretation is correct, GRB 060614 arose from a compact binary merger rather than from the death of a massive star and it was a site of a significant production of heavy r-process elements. The significant ejected mass favours a black hole-neutron star merger but a double neutron star merger cannot be ruled out.

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