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Ján BURKU? Martina KA?MAROVá Janka KUBANDOVá Natália KOKO?OVá Kamila FABIANOVá Du?an FABIAN Juraj KOPPEL ?tefan ?IKO? 《The Journal of reproduction and development》2015,61(4):325-331
We found retardation of preimplantation embryo growth after exposure to maternal restraint stress during the preimplantation period in our previous study. In the present study, we evaluated the impact of preimplantation maternal restraint stress on the distribution of inner cell mass (ICM) and trophectoderm (TE) cells in mouse blastocysts, and its possible effect on physiological development of offspring. We exposed spontaneously ovulating female mice to restraint stress for 30 min three times a day during the preimplantation period, and this treatment caused a significant increase in blood serum corticosterone concentration. Microscopic evaluation of embryos showed that restraint stress significantly decreased cell counts per blastocyst. Comparing the effect of restraint stress on the two blastocyst cell lineages, we found that the reduction in TE cells was more substantial than the reduction in ICM cells, which resulted in an increased ICM/TE ratio in blastocysts isolated
from stressed dams compared with controls. Restraint stress reduced the number of implantation sites in uteri, significantly delayed eye opening in delivered mice, and altered their behavior in terms of two parameters (scratching on the base of an open field test apparatus, time spent in central zone) as well. Moreover, prenatally stressed offspring had significantly lower body weights and in 5-week old females delivered from stressed dams, fat deposits were significantly lower. Our results indicate that exposure to stress during very early pregnancy can have a negative impact on embryonic development with consequences reaching into postnatal life. 相似文献
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Masursky H Batson RM McCauley JF Soderblom LA Wildey RL Carr MH Milton DJ Wilhelms DE Smith BA Kirby TB Robinson JC Leovy CB Briggs GA Duxbury TC Acton CH Murray BC Cutts JA Sharp RP Smith S Leighton RB Sagan C Veverka J Noland M Lederberg J Levinthal E Pollack JB Moore JT Hartmann WK Shipley EN De Vaucouleurs G Davies ME 《Science (New York, N.Y.)》1972,175(4019):294-305
At orbit insertion on 14 November 1971 the Martian surface was largely obscured by a dust haze with an extinction optical depth that ranged from near unity in the south polar region to probably greater than 2 over most of the planet. The only features clearly visible were the south polar cap, one dark, spot in Nix Olympica, and three dark spots in the Tharsis region. During the third week the atmosphere began to clear and surface visibility improved, but contrasts remained a fraction of their normal value. Each of the dark spots that apparently protrude through most of the dust-filled atmosphere has a crater or crater complex in its center. The craters are rimless and have featureless floors that, in the crater complexes, are at different levels. The largest crater within the southernmost spot is approximately 100 kilometers wide. The craters apparently were formed by subsidence and resemble terrestrial calderas. The south polar cap has a regular margin, suggsting very flat topography. Two craters outside the cap have frost on their floors; an apparent crater rim within the cap is frost free, indicating preferentia loss of frost from elevated ground. If this is so then the curvilinear streaks, which were frost covered in 1969 and are now clear of frost, may be low-relief ridges. Closeup pictures of Phobos and Deimos show that Phobos is about 25 +/-5 by 21 +/-1 kilometers and Deimos is about 13.5 +/- 2 by 12.0 +/-0.5 kilometers. Both have irregular shapes and are highly cratered, with some craters showing raised rims. The satellites are dark objects with geometric albedos of 0.05. 相似文献
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Kelsey L Batson Hilda I Caldern Mike D Tokach Jason C Woodworth Robert D Goodband Steve S Dritz Joel M DeRouchey 《Journal of animal science》2021,99(5)
Two experiments were conducted to determine the effects of crude protein (CP) level in diets containing coarse wheat bran (CWB) with or without pharmacological levels of Zn (provided by zinc oxide: ZnO) on growth performance and fecal DM of nursery pigs. In experiment 1, 360 barrows (Line 200 × 400, DNA, Columbus, NE, initially 5.6 kg) were allotted to 1 of 6 dietary treatments from d 0 to 21 after weaning with 5 pigs per pen and 12 pens per treatment. Treatments included a positive control diet (21% CP) with 3,000 mg/kg Zn in phase 1 and 2,000 mg/kg in phase 2; negative control (21% CP) with 110 mg/kg added Zn, and 4 diets containing 4% CWB and 110 mg/kg added Zn formulated to contain 21%, 19.5%, 18%, or 16.5% CP. The 2 control diets and 21% CP CWB diet contained 1.40% standardized ileal digestible (SID) Lys in phase 1 and 1.35% SID Lys in phase 2, while the 19.5%, 18%, and 16.5% CP diets contained 1.33, 1.25 and 1.20% Lys, respectively, in both phases. Pigs fed the positive control diet containing pharmacological ZnO had increased (P < 0.05) ADG and G:F compared with the negative control and the 21% CP CWB diet. Reducing CP (concurrently with SID Lys) in diets containing CWB decreased ADG and G:F (linear, P = 0.002); however, fecal DM increased (linear, P = 0.005). In experiment 2, two groups of 300 and 350 pigs, initially 7.0 and 6.2 kg, respectively, were used with 5 pigs per pen and 26 pens per treatment. The objective was to determine if adding back essential AA would improve growth performance of pigs fed the low CP diets. All dietary treatments were fed for 13 days, contained 4% CWB, and consisted of: (1) positive control with 2,000 mg/kg of Zn and 21% CP (1.35% SID Lys); (2) no ZnO and 21% CP; and 3 diets with no ZnO formulated to 18% CP and (3) 1.2% SID Lys; (4) 1.35% SID Lys by the addition of feed grade amino acids (AA), and (5) diet 4 with non-essential amino acids (NEAA; Gly and Glu). Pigs fed 21% CP with ZnO had increased (P = 0.001) ADG compared to those fed 18% CP (1.35% SID Lys) with high levels of feed grade amino acids or those fed the reduced SID Lys (1.2%) diet. Overall, G:F was improved (P < 0.001) for pigs fed 21% CP diets and those fed the 18% CP diet with NEAA compared to pigs fed 1.2% SID Lys and pigs fed high levels of feed grade amino acids. Fecal DM was increased for pigs fed the reduced SID Lys diet. In summary, pharmacological levels of Zn improve pig growth performance, but reducing CP (and subsequently SID Lys) decreased nursery pig growth performance. 相似文献
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With current advances in sub-angstrom resolution scanning transmission electron microscopy (STEM), it is now possible to image directly local crystal structures of materials where dramatically different atoms are separated from each other at distances about or less than 1 angstrom. We achieved direct imaging of atomic columns of nitrogen in close proximity to columns of aluminum in wurtzite aluminum nitride by using annular dark field imaging in an aberration-corrected STEM. This ability allows direct determination of the local polarity in nanoscale crystals and crystal defects. 相似文献
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It has become accepted that the horse cannot see directly in front when the nose is lowered and must therefore rely on the rider. We tested the hypothesis that this conclusion would be correct only if the horse did not adjust the eyeball horizontal axis to changes of the head position. The results of the present study suggest that it is unlikely that horses have limited vision in relation to their head position when driven by the rider, and that the horse maintains the optimal horizontal eyeball position regardless of head position relative to the ground. 相似文献
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Elliott ML Des Jardin EA Batson WE Caceres J Brannen PM Howell CR Benson DM Conway KE Rothrock CS Schneider RW Ownley BH Canaday CH Keinath AP Huber DM Sumner DR Motsenbocker CE Thaxton PM Cubeta MA Adams PD Backman PA Fajardo J Newman MA Pereira RM 《Pest management science》2001,57(8):695-706
Cotton and snap bean were selected for a multi-year, multi-state regional (south-eastern USA) research project to evaluate the efficacy of both commercial and experimental bacterial and fungal biological control agents for the management of damping-off diseases. The goal for this portion of the project was to determine the viability and stability of biological agents after application to seed. The biological seed treatments used included: (1) Bacillaceae bacteria, (2) non-Bacillaceae bacteria, (3) the fungus Trichoderma and (4) the fungus Beauveria bassiana. Seed assays were conducted to evaluate the following application factors: short-term (< or = 3 months) stability after seed treatment; quality (i.e. isolate purity); compatibility with chemical pesticides and other biocontrol agents; application uniformity between years and plant species. For the bacterial treatments, the Bacillaceae genera (Bacillus and Paenibacillus) maintained the greatest population of bacteria per seed, the best viability over time and the best application uniformity across years and seed type. The non-Bacillaceae genera Burkholderia and Pseudomonas had the least viability and uniformity. Although Beauveria bassiana was only evaluated one year, the seed fungal populations were high and uniform. The seed fungal populations and uniformity for the Trichoderma isolates were more variable, except for the commercial product T-22. However, this product was contaminated with a Streptomyces isolate in both the years that it was evaluated. The study demonstrated that Bacillaceae can be mixed with Trichoderma isolates or with numerous pesticides to provide an integrated pest control/growth enhancement package. 相似文献
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Smith BA Soderblom L Batson R Bridges P Inge J Masursky H Shoemaker E Beebe R Boyce J Briggs G Bunker A Collins SA Hansen CJ Johnson TV Mitchell JL Terrile RJ Cook AF Cuzzi J Pollack JB Danielson GE Ingersoll AP Davies ME Hunt GE Morrison D Owen T Sagan C Veverka J Strom R Suomi VE 《Science (New York, N.Y.)》1982,215(4532):504-537
Voyager 2 photography has complemented that of Voyager I in revealing many additional characteristics of Saturn and its satellites and rings. Saturn's atmosphere contains persistent oval cloud features reminiscent of features on Jupiter. Smaller irregular features track out a pattern of zonal winds that is symmetric about Saturn's equator and appears to extend to great depth. Winds are predominantly eastward and reach 500 meters per second at the equator. Titan has several haze layers with significantly varying optical properties and a northern polar "collar" that is dark at short wavelengths. Several satellites have been photographed at substantially improved resolution. Enceladus' surface ranges from old, densely cratered terrain to relatively young, uncratered plains crossed by grooves and faults. Tethys has a crater 400 kilometers in diameter whose floor has domed to match Tethys' surface curvature and a deep trench that extends at least 270 degrees around Tethys' circumference. Hyperion is cratered and irregular in shape. Iapetus' bright, trailing hemisphere includes several dark-floored craters, and Phoebe has a very low albedo and rotates in the direction opposite to that of its orbital revolution with a period of 9 hours. Within Saturn's rings, the "birth" of a spoke has been observed, and surprising azimuthal and time variability is found in the ringlet structure of the outer B ring. These observations lead to speculations about Saturn's internal structure and about the collisional and thermal history of the rings and satellites. 相似文献
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Batson PE 《Science (New York, N.Y.)》2012,335(6064):47-48
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