目的::研究健康体检人群中眼底杯盘比增大者的眼压分布情况.方法::从本单位2019年度完成眼底检查和非接触眼压测量的健康体检人群中,将任何一眼杯盘比≥0.5的受检者纳入研究范围,并依据眼科疾病检查情况分为有相关眼病组和无相关眼病组...目的::研究健康体检人群中眼底杯盘比增大者的眼压分布情况.方法::从本单位2019年度完成眼底检查和非接触眼压测量的健康体检人群中,将任何一眼杯盘比≥0.5的受检者纳入研究范围,并依据眼科疾病检查情况分为有相关眼病组和无相关眼病组,将两组受检者的眼压情况进行分析.结果::无相关眼病组的杯盘比增大人群,眼压呈正态分布(P>0.05),右眼压的范围为最小值10 mm Hg到最大值30 mm Hg,左眼压范围为最小值9 mm Hg到最大值31 mm Hg.有相关眼病组的杯盘比增大人群,眼压分布区间窄,且双眼呈现不一致的分布态势.无相关眼病组男女性左眼眼压有统计学差异,男性左眼眼压明显高于女性(P<0.01),右眼眼压有统计学差异,男性右眼眼压较女性更高(P<0.05);有相关眼病组男女性左眼眼压和右眼眼压均没有统计学差异.无相关眼病组无论男性(P<0.001)和女性(P<0.01),左眼压均高于右眼压;而在有相关眼病人群中,无论男性(P<0.05)和女性(P<0.05),右眼压均高于左眼压.结论:相对健康人群中有很大比例(90.6%)的生理性杯盘比增大者(眼压在正常范围内,视力及视野情况无青光眼指向),进一步证实了大凹陷并非均为病理性,虽然杯盘比≥0.6被定为青光眼筛查的指标,但是在正常人与青光眼患者中有重叠现象.健康体检中进行眼底及眼压检查非常必要,可以筛查出杯盘比增大且眼压增高的青光眼待排查人群.相对健康人群中男性眼压较女性更高,左眼眼压比右眼高.展开更多
In this paper,a property of Frequency Hopping (FH) sequence set with No Hit Zone (NHZ) is analyzed. Based on matrix transform and mapping methods,respectively,two classes of NHZ FH sequences are presented. These NHZ F...In this paper,a property of Frequency Hopping (FH) sequence set with No Hit Zone (NHZ) is analyzed. Based on matrix transform and mapping methods,respectively,two classes of NHZ FH sequences are presented. These NHZ FH sequences have good Hamming auto-correlation and Hamming cross-correlation properties. FH Code-Division Multiple Access (FH-CDMA) communication systems employing such NHZ FH sequences will eliminate multiple-access interference if the maximum time delay is shorter than the length of the NHZ.展开更多
The contents of the soil microbial biomass nitrogen (SMBN) in the soils sampled from the Loess Plateau of China were determined using chloroform fumigation aerobic incubation method (CFAIM), chloroform fumigation anae...The contents of the soil microbial biomass nitrogen (SMBN) in the soils sampled from the Loess Plateau of China were determined using chloroform fumigation aerobic incubation method (CFAIM), chloroform fumigation anaerobic incubation method (CFANIM) and chloroform fumigation-extraction method (CFEM).The N taken up by ryegrass on the soils was determined after a glasshouse pot experiment. The flushes of nitrogen (FN) of the soils obtained by the CFAIM and CFANIM were higher than that by the CFEM, and there were significantly positive correlations between the FN obtained by the 3 methods. The N extracted from the fumigated soils by the CFAIM, CFANIM and CFEM were significantly positively correlated with the N uptake by ryegrass. The FN obtained by the 3 methods was also closely positively correlated with the plant N uptake. The contributions of the SMBN and mineral N and mineralized N during the incubation period to plant N uptake were evaluated with the multiple regression method. The results showed that the N contained in the soil microbial biomass might play a noticeable role in the N supply of the soils to the plant.展开更多
In this paper, a weighted fractional Fourier transform(WFRFT) based cooperative overlay system, aiming to guarantee physical layer(PHY) security, is proposed. The paper elaborates how WFRFT and physical layer properti...In this paper, a weighted fractional Fourier transform(WFRFT) based cooperative overlay system, aiming to guarantee physical layer(PHY) security, is proposed. The paper elaborates how WFRFT and physical layer properties of the wireless medium are collaborated to guarantee the secrecy of wireless transmissions. In the proposed system, WFRFT is first preform on the secret data, such that the transmitted signal is distorted and can only be neutralized by inverse-WFRFT with the same parameter. And then two streams of the transformed sequences that bearing different messages are cooperatively and simultaneously transmitted to two legitimate receivers via a beamforming-liked method, respectively. In general, both the rapid spatial decorrelation property and the inherent security features of WFRFT are leveraged, such that only the eavesdropper's is degraded, and hence, the wireless communication secrecy is reliably guaranteed. Numerical simulations are conducted to evaluate the performance of the proposed system in terms of the average bit error rate and the secrecy capacity.展开更多
文摘目的::研究健康体检人群中眼底杯盘比增大者的眼压分布情况.方法::从本单位2019年度完成眼底检查和非接触眼压测量的健康体检人群中,将任何一眼杯盘比≥0.5的受检者纳入研究范围,并依据眼科疾病检查情况分为有相关眼病组和无相关眼病组,将两组受检者的眼压情况进行分析.结果::无相关眼病组的杯盘比增大人群,眼压呈正态分布(P>0.05),右眼压的范围为最小值10 mm Hg到最大值30 mm Hg,左眼压范围为最小值9 mm Hg到最大值31 mm Hg.有相关眼病组的杯盘比增大人群,眼压分布区间窄,且双眼呈现不一致的分布态势.无相关眼病组男女性左眼眼压有统计学差异,男性左眼眼压明显高于女性(P<0.01),右眼眼压有统计学差异,男性右眼眼压较女性更高(P<0.05);有相关眼病组男女性左眼眼压和右眼眼压均没有统计学差异.无相关眼病组无论男性(P<0.001)和女性(P<0.01),左眼压均高于右眼压;而在有相关眼病人群中,无论男性(P<0.05)和女性(P<0.05),右眼压均高于左眼压.结论:相对健康人群中有很大比例(90.6%)的生理性杯盘比增大者(眼压在正常范围内,视力及视野情况无青光眼指向),进一步证实了大凹陷并非均为病理性,虽然杯盘比≥0.6被定为青光眼筛查的指标,但是在正常人与青光眼患者中有重叠现象.健康体检中进行眼底及眼压检查非常必要,可以筛查出杯盘比增大且眼压增高的青光眼待排查人群.相对健康人群中男性眼压较女性更高,左眼眼压比右眼高.
基金the National Natural Science Foundation of China (No.90604035 and 60572142)the Program for New Century Excellent Talents in University (NCET) (No.NECT-05-0795).
文摘In this paper,a property of Frequency Hopping (FH) sequence set with No Hit Zone (NHZ) is analyzed. Based on matrix transform and mapping methods,respectively,two classes of NHZ FH sequences are presented. These NHZ FH sequences have good Hamming auto-correlation and Hamming cross-correlation properties. FH Code-Division Multiple Access (FH-CDMA) communication systems employing such NHZ FH sequences will eliminate multiple-access interference if the maximum time delay is shorter than the length of the NHZ.
基金the National Natural Science Foundation of China(Nos.49890330,39770425 and 30070429) the National Key Basic Research Support Foundation of China(No.G1999011707).
文摘The contents of the soil microbial biomass nitrogen (SMBN) in the soils sampled from the Loess Plateau of China were determined using chloroform fumigation aerobic incubation method (CFAIM), chloroform fumigation anaerobic incubation method (CFANIM) and chloroform fumigation-extraction method (CFEM).The N taken up by ryegrass on the soils was determined after a glasshouse pot experiment. The flushes of nitrogen (FN) of the soils obtained by the CFAIM and CFANIM were higher than that by the CFEM, and there were significantly positive correlations between the FN obtained by the 3 methods. The N extracted from the fumigated soils by the CFAIM, CFANIM and CFEM were significantly positively correlated with the N uptake by ryegrass. The FN obtained by the 3 methods was also closely positively correlated with the plant N uptake. The contributions of the SMBN and mineral N and mineralized N during the incubation period to plant N uptake were evaluated with the multiple regression method. The results showed that the N contained in the soil microbial biomass might play a noticeable role in the N supply of the soils to the plant.
基金supported by the National Basic Research Program of China under Grant 2013CB329003the National Natural Science Founda-tion General Program of China under Grant 61171110
文摘In this paper, a weighted fractional Fourier transform(WFRFT) based cooperative overlay system, aiming to guarantee physical layer(PHY) security, is proposed. The paper elaborates how WFRFT and physical layer properties of the wireless medium are collaborated to guarantee the secrecy of wireless transmissions. In the proposed system, WFRFT is first preform on the secret data, such that the transmitted signal is distorted and can only be neutralized by inverse-WFRFT with the same parameter. And then two streams of the transformed sequences that bearing different messages are cooperatively and simultaneously transmitted to two legitimate receivers via a beamforming-liked method, respectively. In general, both the rapid spatial decorrelation property and the inherent security features of WFRFT are leveraged, such that only the eavesdropper's is degraded, and hence, the wireless communication secrecy is reliably guaranteed. Numerical simulations are conducted to evaluate the performance of the proposed system in terms of the average bit error rate and the secrecy capacity.
