Nuclei isolated from cultured mouse and rat cell lines initiated pre-rRNA chains at the correct site and with the correct nucleotide specificity (A for mouse, G for rat). Nucleic acid filter hybridization and S1 nuclease mapping were used to analyze the RNA products initiated with nucleoside (P-S)triphosphates. Initiation of pre-rRNA was completely resistant to a-amanitin but was inhibited by either actinomycin D or heparin. Experiments with P1798 mouse lymphoma cells indicated that the antiproliferative effects of glucocorticoids on lymphoid cells includes a reduction in the ability of nuclei to initiate pre-rRNA chains.

<div class="ftSection"><span class="ftInlineSubsectionTitle">Purpose:</span><p>To evaluate whether accommodation has effects on eye elongation.</p></div><div class="ftSection"><span class="ftInlineSubsectionTitle">Methods:</span><p>Two hundred seventy-three eyes with a refractive error between +1.0 and −0.5 diopters were divided into three groups: pre-school children, grade-school children, and middle-school children. Ocular structures were measured using autorefraction and A-scan ultrasonography.</p></div><div class="ftSection"><span class="ftInlineSubsectionTitle">Results:</span><p>There was a negative correlation between age and corneal power (r = −0.227, <italic>P</italic> = .0001), lens thickness (r = −0.263, <italic>P</italic> = .00001), and Gullstrand lens power (r = −0.452, <italic>P</italic> &lt;&lt; .0001). There was a positive correlation between age and axial length (r = −0.432, <italic>P</italic> &lt;&lt; .0001) and vitreous chamber depth (r = 0.505, <italic>P</italic> &lt;&lt; .0001). Mean corneal power (<italic>P</italic> &lt; .001) and lens power (<italic>P</italic> &lt; .001) were significantly greater in pre-school children than in grade-school children, whereas axial length (<italic>P</italic> &lt; .001) and vitreous chamber depth (<italic>P</italic> &lt; .001) were greater in grade-school children. Mean lens thickness (<italic>P</italic> = .01) and lens power (<italic>P</italic> = .07) were higher in grade-school children than in middle-school children, whereas axial length (<italic>P</italic> = .024) and vitreous chamber depth (<italic>P</italic> &lt; .001) were higher in middle-school children.</p></div><div class="ftSection"><span class="ftInlineSubsectionTitle">Conclusion:</span><p>Ocular structures may play different roles in maintaining emmetropia. Accommodation during near work and its potential attendant hyperopic defocus could potentially drive eye elongation.</p></div>

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While high steel grade X70, X80 pipeline has been widely used in long-distance oil and gas pipeline engineering of China, to further improve steel grade to X90 is an effective way to increase the efficiency of pipeline transportation and reduce construction cost. In this paper, the failure probability of earthquake fault crossing of X90 pipeline has been calculated with the strain-based reliability design method and the design scheme has been adjusted according to sensitivity analysis with influence factors of the failure probability of fault-crossing of X90 pipeline, after that the scheme of fault-crossing of X90 pipeline which meets requirements of pipeline reliability has been figured out. This study has laid a theoretical foundation for the application of X90 pipeline in future construction of pipeline engineering.