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关键词： 线性回归模型   长记忆随机波动率误差   变点检验   自正则CUSUM统计量  

摘要： 本文研究带有能同时刻画长记忆性和异方差性的长记忆随机波动率误差的线性回归模型结构变点的检验问题,基于最小二乘估计残差构造了一种不需要估计尺度参数的自正则CUSUM统计量.在原假设下推导出了检验统计量的极限分布,发现其不受长记忆参数的影响,在备择假设下证明了统计量的一致性.数值模拟结果表明,本文所提方法不仅能够很好地控制经验水平,且能达到较好的检验功效.最后通过对一组西宁市空气中的PM2.5浓度与SO2浓度数据建模和检验其中的结构变点说明了所提方法的有效性.

关键词： Anatomic shoulder arthroplasty   stemless humeral head  

摘要： BACKGROUND:Anatomic total shoulder arthroplasty (aTSA) is a well described technique for addressing glenohumeral osteoarthritis. Little has been written on outcomes for newer stemless humeral implants in older patients, with none looking specifically at an implant relying on screw fixation. The purpose of this study is to evaluate the clinical and radiographic outcomes for patients over 70 years of age undergoing aTSA with the Eclipse (Arthrex Inc., Naples, FL, USA) stemless humeral component. METHODS:A retrospective review utilizing a multicenter shoulder arthroplasty registry was performed evaluating all patients over 70 who underwent aTSA with a stemless humeral implant for a diagnosis of glenohumeral osteoarthritis and had a minimum follow-up of 2 years. Thirty-seven patients met the study criteria and were matched for comparative analysis to 37 patients 65 years of age and younger. Outcome scores were obtained preoperatively and at 2 years postoperatively using the VAS (Visual Analog Scale), Constant-Murley, American Shoulder and Elbow Surgeons (ASES) and Western Ontario Osteoarthritis Index (WOOS) scores. The percentage of patients in each group who exceeded the MCID for the ASES and WOOS was reported. When available, postoperative radiographs were evaluated for the presence of radiolucent lines and calcar resorption. RESULTS:There was a statistically significantly higher preoperative WOOS score in the older patient group, otherwise there was not statistical difference between the two groups in regards to baseline scores or range of motion. At two-year follow-up, older patients were noted to have significantly better VAS, ASES, WOOS, and Constant-Murley scores when compared to younger patients (p < .05). All patients over the age of 70 achieved MCID for the ASES compared to 84% of those 65 and younger (p=0.011), while for the WOOS 100% of older patients achieved MCID compared to 86% of those in the control group (p=0.022). Postoperative range of motion was not

关键词： 禽流感   EA H1N1 SIV   GGCX   受体结合活性  

摘要： 禽流感病毒对养禽业造成严重的经济损失，也对公共卫生安全造成严重威胁。禽流感病毒的自然宿主是禽类，由于物种间种属屏障，通常难以感染哺乳动物。然而，禽流感病毒在宿主因子的驱动下发生适应性突变后可突破物种屏障感染哺乳动物。2025年1月15日，华中农业大学周红波教授带领的研究团队在Nature Communications上发表了题为“GGCX promotes Eurasian avian-like H1N1 swine influenza virus adaption to interspecies receptor binding”的研究论文，揭示了禽流感病毒在宿主因子GGCX的驱动下发生适应性突变的分子机制，增强了人们对禽流感病毒跨物种感染哺乳动物的认识，同时为开发抗病毒新策略，阻断禽流感病毒的感染与传播提供了理论支持。

关键词： 二化螟   稻纵卷叶螟   大螟   稻飞虱   性信息素   交配干扰  

摘要： 【目的】探索性信息素交配干扰法对水稻二化螟Chilo supperssalis、大螟Sesamia inferens和稻纵卷叶螟Cnaphalocrocis medinalis求偶行为和防控效果的影响，以及对非靶标害虫稻飞虱Nilaparvata lugens种群的影响。【方法】在湖南攸县晚稻田中设置释放器，在每日晚上求偶期主动喷射超剂量性信息素，同期性诱监测二化螟、稻纵卷叶螟和大螟的蛾量，田间调查二化螟、大螟和稻纵卷叶螟的危害率和幼虫密度，以及褐飞虱的虫量。【结果】多靶标性信息素释放器释放的气味有效干扰了二化螟、大螟和稻纵卷叶螟的求偶行为，田间3种鳞翅目害虫的诱蛾量显著下降，二化螟、稻纵卷叶螟和大螟的平均总迷向率分别为86.84%±1.69%、86.18%±2.16%和86.13%±1.92%。二化螟田间危害情况调查交配干扰区平均防效为81.08%±4.73%，相对对照区幼虫减退率为85.25%±4.89%。稻纵卷叶螟田间危害情况调查交配干扰区平均防效为90.63%±3.06%。大螟田间危害调查发现交配干扰区平均防效为56.85%±3.53%，幼虫减退率为54.97%±3.52%。交配干扰区的稻飞虱种群数量显著低于对照区（t=4.12,df=18,P<0.001），平均减少83.54%±2.29%。在对照区，二化螟外围幼虫数量显著高于中间田块（F=20.17, df=9, P<0.001），但在交配干扰环境下，二化螟在水稻的外围密度与中间田块无显著差异（F=0.112, df=9, P=0.895）。【结论】多靶标性信息素释放器可通过直接干扰求偶行为有效防控二化螟、大螟和稻纵卷叶螟，可能由于保护了田间天敌种群，间接抑制了稻飞虱的种群数量。