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Effects of Dietary Straw Content on Growth and Development of Locusta migratoria and Its Egg Hatching
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作者 Siyu LI Doudou SHI Shanmin QU 《Agricultural Biotechnology》 CAS 2023年第3期61-65,共5页
[Objectives]This study was conducted to investigate the effects of dietary straw content on the growth and development of oriental migratory locusts(Locusta migratoria),as well as the effects of temperature and substr... [Objectives]This study was conducted to investigate the effects of dietary straw content on the growth and development of oriental migratory locusts(Locusta migratoria),as well as the effects of temperature and substrate on their egg hatching.[Methods]The eggs of oriental migratory locusts were hatched at 15,20,25,30,35,and 40℃in sawdust,soil and sawdust+soil conditions,respectively,to determine suitable environmental conditions for artificial hatching of oriental migratory locusts.Rice straw was added at 0%,20%,40%,60%,80%and 100%to the basic diet,and the obtained diets was feed to oriental migratory locusts at the 4^(th)instar,to investigate the effects on their growth and development.[Results]The eggs of oriental migratory locusts had a good hatching rate at 25-30℃,and sawdust was the best choice for their hatching substrate.Adding 40%of rice straw to the diet could ensure the normal growth and development of oriental migratory locusts while consuming as much rice straw as possible.[Conclusions]This study explored a technical solution for efficiently producing insect protein from discarded crop straw(treating waste with insects,and turning waste into treasure),providing support for breeding of oriental migratory locusts and locust disaster prevention. 展开更多
关键词 Straw feed SUBSTRATE Oriental migratory locust hatching rate TEMPERATURE
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Monochromatic green light stimulation during incubation shortened the hatching time via pineal function in White Leghorn eggs 被引量:3
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作者 Panlin Wang Yanyan Sun +13 位作者 Yunlei Li Jing Fan Yunhe Zong Adamu Mani Isa Lei Shi Yuanmei Wang Aixin Ni Pingzhuang Ge Linlin Jiang Shixiong Bian Hui Ma Zhengdong Yuan Xiaolin Liu Jilan Chen 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第3期1226-1235,共10页
Background:Effect of monochromatic green light illumination on embryo development has been reported in chickens.The avian pineal gland is an important photo-endocrine organ formed by a mediodorsal protrusion during em... Background:Effect of monochromatic green light illumination on embryo development has been reported in chickens.The avian pineal gland is an important photo-endocrine organ formed by a mediodorsal protrusion during embryonic development.However,the involvement of pineal gland in the light transduction process remains to be elucidated.In the present study,we investigated the influence of monochromatic green light on hatching time and explored the possible mechanism via pineal function.Results:A total of 600 eggs of White Leghorn(Shaver strain)were incubated under photoperiods of either 12 h of light and 12 h of darkness using monochromatic green light(12L:12D group)or 24 h of darkness(0L:24D group)for 18 d.Compared to 0L:24D group,the green light stimulation shortened the hatching time without extending the hatch window or impairing hatchability.The liver of embryos incubated in the 12L:12D light condition was heavier than those of the 0L:24D group on d 21 post incubation which may be linked to the observed increase in the serum concentration of insulin-like growth factor 1(IGF-1);primary secretion of the liver.Histological structure analysis of pineal gland demonstrated that the light stimulation increased follicle area,wall thickness and lumen area on d 10 and d 12 post incubation.Rhythmic function analysis demonstrated that three clock related genes(brain and muscle ARNT-like-1,BMAL1;circadian locomotor output cycles kaput,CLOCK;and cryptochrome-1,CRY1)and a melatonin rate-limiting enzyme related gene(arylalkylamine N-acetyltransferase,AANAT)were rhythmically expressed in the pineal gland of the 12L:12D group,but not in the 0L:24D group.Simultaneously,the light stimulation also increased the concentration of melatonin(MT),which was linked to hepatocyte proliferation and IGF-1 secretion in previous studies.Conclusions:The 12L:12D monochromatic green light stimulation during incubation shortened hatching time without impairing hatching performance.Pineal gland’s early histological development and maturation of its rhythmic function were accelerated by the light stimulation.It may be the key organ in the photo-endocrine axis that regulates embryo development,and the potential mechanism could be through enhanced secretion of MT in the 12L:12D group which promotes the secretion of IGF-1. 展开更多
关键词 Circadian rhythm hatching time Insulin-like growth factor 1 MELATONIN Monochromatic green light Pineal gland
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Effect of laser assisted hatching on outcome of assisted reproductive technology 被引量:5
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作者 Amro Elhussieny Mohamed El Mandouh +2 位作者 Sherif Hanafi Ghada M. Mansour Ahmed El-Kotb 《Open Journal of Obstetrics and Gynecology》 2013年第5期18-23,共6页
Objective: To determine whether laser-assisted hatching can improve clinical outcome of assisted reproductive techniques in both unselected patients and patients with advanced female age, with recurrent implantation f... Objective: To determine whether laser-assisted hatching can improve clinical outcome of assisted reproductive techniques in both unselected patients and patients with advanced female age, with recurrent implantation failure, or who are using frozen-thawed embryos. Study design: Prospective randomized study. Patients and methods: 179 consecutive women scheduled for intracytoplasmic sperm injection (ICSI) were randomised to either laser assisted hatching (LAH) or non LAH group. Patients were divided into 94 test and 85 control groups. On the day of embryo transfer, the zona pellucida of the selected embryos in the test group was thinned by using an infrared optical laser system, whereas in the control group they were left intact. Clinical pregnancy rates (CPR) and implantation rates (IR) were estimated. Result(s): Patients that underwent LAH (n = 94) had CPR, and IR of 35.1% and 50%, respectively. Patients that did not undergo LAH (n = 85) had lower CPR (28.2%, P = 0.324) and IR (33%, P = 230), with no statistically significant difference P Conclusion: The current study suggested that there is no need for the routine use of laser assisted hatching. However, there is evidence of laser assisted hatching benefit in selected 展开更多
关键词 Laser-Assisted hatching Advanced Female Age IMPLANTATION FAILURES EMBRYO CRYOPRESERVATION and Pregnancy Rate
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Effects of Lanthanum on Egg Hatching and Nauplius Metamorphosis of Penaeus Chinensis 被引量:1
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作者 辛福言 袁有宪 曲克明 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第3期73-76,共4页
EfectsofLanthanumonEggHatchingandNaupliusMetamorphosisofPenaeusChinensisXinFuyan(辛福言),YuanYouxian(袁有宪),Qu... EfectsofLanthanumonEggHatchingandNaupliusMetamorphosisofPenaeusChinensisXinFuyan(辛福言),YuanYouxian(袁有宪),QuKeming(曲克明)(Yelow... 展开更多
关键词 Rare earths LANTHANUM PENAEUS CHINENSIS EGG hatching Nauplius METAMORPHOSIS
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In Vitro Fertilization Outcomes Following Assisted Hatching of Embryos with Thick Zona Pellucida—A Prospective Randomized Study 被引量:1
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作者 Mara Koifman Shirly Lahav-Baratz +5 位作者 Libby Shopen Blais Idit David Ishai Zofnat Wiener-Megnazi Ron Auslender Martha Dirnfeld 《Advances in Reproductive Sciences》 2014年第4期76-82,共7页
Purpose: Impaired hatching is associated with implantation failure following in vitro fertilization (IVF). Thickening or hardening of the zona pellucida (ZP) has been proposed as a factor in this impairment. We examin... Purpose: Impaired hatching is associated with implantation failure following in vitro fertilization (IVF). Thickening or hardening of the zona pellucida (ZP) has been proposed as a factor in this impairment. We examined whether selective assisted hatching (AH) is beneficial with embryos having a thick ZP. Methods: This prospective, randomized controlled study was performed in the IVF unit of an obstetrics and gynecology department in a university-affiliated hospital. Only patients undergoing IVF and having a ZP thickness of ≥17 μm measured in all their embryos were included. In the intervention group, AH was applied to all embryos, before their transfer. In the control group, embryos were transferred without AH. Implantation, clinical pregnancy and live birth rates were the study endpoints. Results: Both study arms were comparable in most baseline parameters. The two groups did not differ in implantation rates (14.1% control vs. 8.92% intervention, odds ratio (OR) = 0.5974, 95% confidence interval (CI) 0.325 - 1.1), clinical pregnancy rates (36.7% vs. 25.8%, OR = 0.6025, 95% CI 0.274 - 1.325), or live birth rates (25% vs. 18.9%, OR = 0.7021, 95% CI 0.291 - 1.691). Conclusions: Selecting embryos for AH by their ZP thickness as a sole parameter was not found to be beneficial and to improve IVF outcome. 展开更多
关键词 In VITRO FERTILIZATION Assisted hatching Zona Pellucida Thickness Partial Zona DISSECTION IMPLANTATION Rate
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Sea water environment copper requirement of egg hatching and naupliar metamorphosis of Peaneus chinensis
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作者 Yuan Youxian Qu Keming +1 位作者 Liu Libo Gao Chengnian and Zhang Duxi(Yellow Sea Fisheries Research institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China)(Jimo Fisheries Bureau, Jimo 266200, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1995年第3期421-428,共8页
SeawaterenvironmentcopperrequirementofegghatchingandnaupliarmetamorphosisofPeaneuschinensis¥YuanYouxian;QuKe... SeawaterenvironmentcopperrequirementofegghatchingandnaupliarmetamorphosisofPeaneuschinensis¥YuanYouxian;QuKeming;LiuLibo;GaoC... 展开更多
关键词 EGG hatching COPPER ion PENAEUS CHINENSIS naupliar METAMORPHOSIS
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Nondestructive detection of infertile hatching eggs based on spectral and imaging information 被引量:4
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作者 Zhu Zhihui Liu Ting +2 位作者 Xie Dejun Wang Qiaohua Ma Meihu 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2015年第4期69-76,共8页
In order to quickly distinguish infertile eggs from fertile eggs,the hyperspectral imaging technology consisting of imaging and spectral information was used for detecting the fertile information of eggs.Before hatchi... In order to quickly distinguish infertile eggs from fertile eggs,the hyperspectral imaging technology consisting of imaging and spectral information was used for detecting the fertile information of eggs.Before hatching eggs were incubated,a hyperspectral imaging system(wavelength between 400 to 1000 nm)was used to acquire the images one-by-one manually.The characteristic information of ratios of length to short axis,elongation,roundness and the ratios of the yolk area to the whole area was extracted based on the images.The normalization method was used as the spectral data preprocessing,and then 155 spectral characteristic variables were extracted from 520 nm waveband through the correlation coefficient method.Principal component analysis(PCA)method was adopted to reduce the dimensions of image-spectrum fusion information;the top six principal components were extracted.Support vector machine(SVM)method was used to establish classification of fertile and infertile eggs models,which are based on image,spectrum and image-spectrum fusion information respectively.The accuracy rates of the SVM models were 84.00%,90.00%and 93.00%respectively.The experimental results show that the model based on image-spectrum fusion information technology is superior to the single information model.Hyperspectral transmission imaging technology is effective and feasible to detect the fertile hatching eggs before incubation. 展开更多
关键词 hyperspectral image hatching eggs information fusion nondestructive detection
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不同风险评分预测急性心肌梗死患者急诊经皮冠状动脉介入术后新发心房颤动风险的探索
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作者 彭秋菊 杨蓓 《中国心血管杂志》 北大核心 2024年第1期51-55,共5页
目的评估和比较mC2HEST评分、HATCH评分和CHA_(2)DS_(2)-VASc评分对急性心肌梗死(AMI)患者急诊经皮冠状动脉介入(PCI)术后住院期间新发心房颤动(NOAF)风险的预测价值。方法回顾性研究。连续入选2020年1月1日至2022年11月30日在云南大学... 目的评估和比较mC2HEST评分、HATCH评分和CHA_(2)DS_(2)-VASc评分对急性心肌梗死(AMI)患者急诊经皮冠状动脉介入(PCI)术后住院期间新发心房颤动(NOAF)风险的预测价值。方法回顾性研究。连续入选2020年1月1日至2022年11月30日在云南大学附属医院心血管内科住院诊断为AMI并于发病24 h内行急诊PCI术且术前无心房颤动的患者。收集基线资料,计算患者mC2HEST评分、HATCH评分和CHA_(2)DS_(2)-VASc评分。根据术后住院期间是否出现NOAF分为NOAF组和非NOAF组,对两组间的资料进行差异性分析;比较各评分的NOAF发生率;单因素二元logistic回归分析,以明确这些评分是否是NOAF的独立危险因素;绘制受试者工作特征(ROC)曲线,评估和比较这些评分预测NOAF的能力。结果共纳入508例AMI患者,有45例(8.9%)发生NOAF。NOAF组的mC2HEST评分、HATCH评分和CHA_(2)DS_(2)-VASc评分更高(均为P<0.001);随着评分升高,NOAF的发生率大致呈上升趋势。Logistic回归分析显示,这三个评分均是AMI患者急诊PCI术后住院期间NOAF的危险因素(OR=2.682、2.386和1.782,均为P<0.001)。ROC曲线提示,mC2HEST评分(AUC=0.853)和HATCH评分(AUC=0.842)对AMI患者急诊PCI术后NOAF具有很好的预测价值,它们的预测效能优于CHA_(2)DS_(2)-VASc评分(AUC=0.773,P<0.05)。结论AMI患者急诊PCI术后,mC2HEST评分、HATCH评分和CHA_(2)DS_(2)-VASc评分与住院期间NOAF显著相关,对其有很好的预测价值,而mC2HEST评分、HATCH评分的预测效能优于CHA_(2)DS_(2)-VASc评分。 展开更多
关键词 mC2HEST评分 HATCH评分 CHA2DS2-VASc评分 急性心肌梗死 新发心房颤动 预测价值
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The effect analysis of the diapause duration on the hatching parameters of the artificial semi-annual population of Lymantria dispar caterpillars
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作者 A.V.Sedelnikov 《International Journal of Biomathematics》 SCIE 2021年第8期129-139,共11页
The paper investigates the existence of a relationship between the diapause duration and the temperature threshold of hatching,the variances in temperature and hatching time of the artificial six-month population of L... The paper investigates the existence of a relationship between the diapause duration and the temperature threshold of hatching,the variances in temperature and hatching time of the artificial six-month population of Lymantria dispar caterpillars.A half-year population gives two generations a year under artificial conditions.A comparative analysis of these parameters with similar parameters of the hybrid population of L.dispar,as well as studies by other authors,has been carried out.The Eigen quasispecies model was used for the mathematical formalization of the evolution process.The results of this work can be used to study the evolution of L.dispar. 展开更多
关键词 hatching parameters DIAPAUSE Lymantria dispar artificial population quasispecies model
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Influences of ultrasound on hatching of the fish eggs
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作者 XIE Ruisheng, ZHANG Zhirong(South China Sea Institute of Oceanology. Academia Sinica, Guangzhou 510301)ZHANG Dejun, CHENG Jianzheng and XIA Xianhua(Wuhan Institute of Physics. Academia Sinica, Wuhan 430071) 《Chinese Journal of Acoustics》 1993年第2期159-165,共7页
The effects of ultrasound on the hatching of the goldfish(Carassiusauratus auratus)and loach(Paramisgurnus dabryanus(sauvage))cytulas werestudied.The ultrasound with certain frequencies can accelerate the developmento... The effects of ultrasound on the hatching of the goldfish(Carassiusauratus auratus)and loach(Paramisgurnus dabryanus(sauvage))cytulas werestudied.The ultrasound with certain frequencies can accelerate the developmentof cytulas,induce the embryos to break membrane earlier,increase the survivalrate of larvas,and increase 50% hatching rate of loach cytulas at lower temper-ature. 展开更多
关键词 ULTRASOUND hatching FISH eggs.
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诞生了Insect Hatching山中的小精灵
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作者 欧阳临安(撰文/摄影) 《旅游纵览》 2020年第9期6-13,共8页
有的虫儿刚孵化时.体色很浅,随着时间的推移逐渐加深;有的暂时聚集在一起,几天后分散走开;有的休息一段时间后吃掉自己的卵壳,以补充营养。一个新生命的降临是美好的,充满了喜庆色彩,即便是螳螂这样的职业杀手,此时也没有任何污点。但... 有的虫儿刚孵化时.体色很浅,随着时间的推移逐渐加深;有的暂时聚集在一起,几天后分散走开;有的休息一段时间后吃掉自己的卵壳,以补充营养。一个新生命的降临是美好的,充满了喜庆色彩,即便是螳螂这样的职业杀手,此时也没有任何污点。但这个过程往往伴随着危险,因为那时的它们是最弱小的、最容易受到天敌攻击。 展开更多
关键词 补充营养 体色 hatching
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More than a simple egg:Underlying mechanisms of cold tolerance in avian embryos 被引量:1
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作者 Ibrahim M.Ahmad Dongming Li 《Avian Research》 SCIE CSCD 2023年第2期267-280,共14页
Avian embryos,which develop within eggs,exhibit remarkable tolerance to extremely low temperatures.Despite being a common trait among all birds,the mechanisms underlying this cold tolerance in avian embryos remain lar... Avian embryos,which develop within eggs,exhibit remarkable tolerance to extremely low temperatures.Despite being a common trait among all birds,the mechanisms underlying this cold tolerance in avian embryos remain largely unknown.To gain a better understanding of this phenomenon and the coping mechanisms involved,we reviewed the literature on severe cold tolerance in embryos of both wild and domestic birds.We found that embryos of different bird orders exhibit tolerance to severe cold during their development.In response to cold stress,embryos slow down their heartbeat rates and metabolism.In severe cold temperatures,embryos can suspend these processes,entering a torpid-like state of cardiac arrest.To compensate for these developmental delays,embryos extend their regular incubation periods.Depending on their embryonic age,embryos of all bird species can tolerate acute severe cold regimes;only a few tolerate chronic severe cold regimes.We also discussed various extrinsic and intrinsic factors that affect the tolerance of bird embryos to low temperatures before and after incubation.Cold tolerance appears to be a heritable trait shared by wild and domestic embryos of all bird classes,regardless of egg size or development(altricial/precocial).Driven by environmental variability,cold tolerance in avian embryos is an optimal physiological and ecological strategy to mitigate the adverse effects of cold conditions on their development in response to fluctuating environmental temperatures. 展开更多
关键词 Acute cold tolerance Avian embryo Chronic cold tolerance Embryonic development hatching success Incubation period
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HATCH评分、APPLE评分在心房颤动患者射频消融术后复发的预测价值研究
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作者 李晓刚 于颖慧 +2 位作者 李小伟 张璐 何健 《中国循证心血管医学杂志》 2023年第7期843-846,共4页
目的探讨HATCH评分、APPLE评分在心房颤动(房颤)患者射频消融术后复发的预测价值。方法选取2018年5月至2020年6月于秦皇岛市第一医院心血管内科行射频消融术治疗的105例房颤患者的临床资料进行回顾性分析,观察手术时间、X线曝光时间、... 目的探讨HATCH评分、APPLE评分在心房颤动(房颤)患者射频消融术后复发的预测价值。方法选取2018年5月至2020年6月于秦皇岛市第一医院心血管内科行射频消融术治疗的105例房颤患者的临床资料进行回顾性分析,观察手术时间、X线曝光时间、消融成功率及复发率;且根据术后3个月后是否出现持续时间≥30 s的快速性房性心律失常分为复发组(n=36)和未复发组(n=69),分析影响复发的危险因素,评估HATCH评分、APPLE评分及两项联合评估房颤患者术后复发的AUC值、敏感度、特异度。结果105例房颤患者均顺利完成射频消融术,消融成功率为65.71%,复发率为34.29%。复发组与未复发组在性别、年龄、病程、合并高血压、糖尿病、心力衰竭、估算的肾小球滤过率(eGFR)、持续性房颤、左心室大小、左室射血分数(LVEF)、右室前后径、升主动脉内径、肺动脉主干内径、室内隔厚度、左室后壁厚度、主动脉瓣口血流速度、肌酐等资料比较中,差异均无统计学意义(P>0.05);而在左心房大小、E峰、HATCH评分、APPLE评分等比较中,差异具有统计学意义(P<0.05)。二元Logistic回归分析显示,左心房大小、E峰、HATCH评分、APPLE评分是影响手术治疗后复发的独立危险因素(P<0.001)。ROC曲线分析显示,HATCH评分、APPLE评分及两项联合评估房颤患者术后复发的AUC值分别为(0.747、0.807、0.927,P<0.05);敏感度分别为44.40%、69.40%、94.40;特异度分别为91.30%、85.50%、84.10%。结论HATCH评分、APPLE评分预测房颤患者射频消融术后复发具有一定价值,且两项联合有利于提高敏感度,能为识别术后复发提供指导。 展开更多
关键词 HATCH评分 APPLE评分 射频消融术 心房颤动 复发
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Sexual Dimorphism,Female Reproductive Characteristics and Embryonic Thermosensitivity in the Tonkin Forest Skink(Sphenomorphus tonkinensis)from Hainan,South China
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作者 Yu DU Chixian LIN +2 位作者 Xiaming ZHU Yuntao YAO Xiang JI 《Asian Herpetological Research》 SCIE CSCD 2023年第4期271-279,共9页
We collected 75 adult Tonkin forest skinks(Sphenomorphus tonkinensis) from Hainan, South China and incubated eggs at four constant temperatures ranging from 22 ℃ to 28 ℃ to study sexual dimorphism, female reproducti... We collected 75 adult Tonkin forest skinks(Sphenomorphus tonkinensis) from Hainan, South China and incubated eggs at four constant temperatures ranging from 22 ℃ to 28 ℃ to study sexual dimorphism, female reproductive characteristics and embryonic thermosensitivity. The largest male was 53.4 mm snout-vent length(SVL), and the largest female was 54.3 mm SVL. The mean SVL was slightly greater in adult females(49.9 mm) than in adult males(48.8 mm), but the difference was not significant.Head length, head width, fore-limb length and hindlimb length were longer in adult males and abdomen length was longer in adult females after accounting for SVL. Accordingly, we conclude that S. tonkinensis is basically a sexually size-monomorphic species with sexual dimorphism in head size, abdomen(trunk)length and limb size. Females laid up to two clutches of 1–4 eggs each per egg-laying season from February to May. Egg mass, clutch size and clutch mass were independent of female SVL. Embryonic stages at laying varied from Dufaure and Hubert’s stage 30 to 31. With female SVL held constant, the negative correlation between egg mass and clutch size was not significant, suggesting that the offspring(egg) sizenumber trade-off between is not evident or eggs are well optimized for size in S. tonkinensis. None of the eggs at 28 ℃ hatched;hatching success was lower at 22 ℃ than at 24 ℃ or 26 ℃. The mean incubation length was 52.9 d at 22 ℃, 40.4 d at 24 ℃ and 33.6 d at 26 ℃. Hatchlings from eggs incubated at 22 ℃,24 ℃ and 26 ℃ did not differ morphologically at hatching, suggesting that temperatures within this range do not differentially affect hatchling morphology in S. tonkinensis. 展开更多
关键词 egg hatching success hatchling morphology incubation length reproduction SCINCIDAE sexual dimorphism
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多频GNSS跟踪站接收机观测量相关性分析
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作者 滕月昊 贾小林 +2 位作者 曹创 王龙 张清华 《海洋测绘》 CSCD 北大核心 2023年第4期52-56,71,共6页
为了验证多频GNSS跟踪站接收机观测数据的质量和相关性,为GNSS跟踪站接收机后续研制做出贡献。基于多品牌多频GNSS跟踪站接收机比测试验,评估了观测数据的伪距噪声,对伪距噪声序列、伪距零基线双差序列进行自相关分析,进而对P-L序列从... 为了验证多频GNSS跟踪站接收机观测数据的质量和相关性,为GNSS跟踪站接收机后续研制做出贡献。基于多品牌多频GNSS跟踪站接收机比测试验,评估了观测数据的伪距噪声,对伪距噪声序列、伪距零基线双差序列进行自相关分析,进而对P-L序列从时域和频域角度进行滤波周期分析,验证了多频GNSS跟踪站接收机观测数据的相关性。试验结果表明:多频GNSS跟踪站接收机观测噪声满足相应标准,不同品牌跟踪站接收机的伪距观测量具有不同程度的自相关性,为削弱观测数据的伪距噪声,不同品牌跟踪站接收机对伪距数据做了不同周期的Hatch滤波处理。 展开更多
关键词 载波相位平滑伪距 GNSS跟踪站 测量噪声评估 零基线双差自相关 HATCH滤波
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基于Hatch载波相位平滑算法的Galileo双频精密单点定位性能研究
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作者 彭嘉浚 石迪迪 王沁 《测绘与空间地理信息》 2023年第3期138-141,共4页
为评估Hatch载波相位平滑算法对精密单点精度的影响,以多个MGEX跟踪站数据为解算数据,进行了滤波前后Galileo双频精密单点定位解算实验。实验结果表明,E1/E5a、E1/E5b双频组合精密单点定位精度可以达到厘米级,而E5a/E5b双频组合精密单... 为评估Hatch载波相位平滑算法对精密单点精度的影响,以多个MGEX跟踪站数据为解算数据,进行了滤波前后Galileo双频精密单点定位解算实验。实验结果表明,E1/E5a、E1/E5b双频组合精密单点定位精度可以达到厘米级,而E5a/E5b双频组合精密单点定位精度较差,不适合进行组合定位。Hatch载波相位平滑算法能在一定程度上提升Galileo双频精密单点定位精度,但提升程度较小,提升量都在10%以内。 展开更多
关键词 Hatch载波相位平滑算法 GALILEO 双频 精密单点定位
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基于衰减记忆高斯和滤波的星间精密测距技术 被引量:6
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作者 李理敏 马陆 +1 位作者 任前义 余金培 《电子与信息学报》 EI CSCD 北大核心 2011年第2期295-299,共5页
星间精密测距是导航星座实现自主导航的核心技术。针对导航星座中码测量值精度低但无整周模糊度,载波相位测量值精度高但存在整周模糊度的特点,该文根据贝叶斯递推原理提出了一种衰减记忆高斯和滤波(Fading Memory Gaussian Sum Filter,... 星间精密测距是导航星座实现自主导航的核心技术。针对导航星座中码测量值精度低但无整周模糊度,载波相位测量值精度高但存在整周模糊度的特点,该文根据贝叶斯递推原理提出了一种衰减记忆高斯和滤波(Fading Memory Gaussian Sum Filter,FMGSF)的伪距估计方法。该方法用高斯和形式近似表示系统后验概率密度,并根据卡尔曼滤波原理来更新高斯项的均值和方差,同时引入衰减记忆因子克服由于模型失配导致的滤波结果发散问题,利用重采样解决由于载波相位测量值不确定导致的算法复杂度增加问题。理论分析和仿真结果表明,该文提出的方法不仅能够克服周跳对伪距估计的影响,而且可以获得更好的测距精度。 展开更多
关键词 卫星间精密测距 衰减记忆 高斯和滤波 HATCH滤波 周跳
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GPS双频相位平滑伪距及其单点定位的精度研究 被引量:19
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作者 范士杰 郭际明 彭秀英 《测绘工程》 CSCD 2005年第4期39-42,共4页
讨论了利用Hatch滤波对双频消电离层组合伪距观测值进行相位平滑,对原Hatch滤波公式中的定权方法进行了改进。在此基础上,采用JPL提供的间隔为30 s的sp3事后精密星历和卫星钟差,对GPS双频相位平滑伪距及其单点定位的精度进行了研究。采... 讨论了利用Hatch滤波对双频消电离层组合伪距观测值进行相位平滑,对原Hatch滤波公式中的定权方法进行了改进。在此基础上,采用JPL提供的间隔为30 s的sp3事后精密星历和卫星钟差,对GPS双频相位平滑伪距及其单点定位的精度进行了研究。采用自编软件,利用IGS跟踪站观测数据进行了实际计算,并得出结论。 展开更多
关键词 HATCH滤波 相位平滑伪距 消电离层组合 单点定位
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载波相位平滑伪距及其在差分定位中的应用 被引量:12
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作者 常志巧 郝金明 李军正 《海洋测绘》 2009年第3期21-23,共3页
推导了单频和双频载波相位平滑伪距的Hatch滤波公式,利用两组实测数据进行了载波相位平滑伪距,然后将平滑后的不同观测类型的伪距用于实时差分定位。定位结果表明,C/A码Hatch滤波的差分定位精度高于P码;无电离层组合的Hatch滤波差分定... 推导了单频和双频载波相位平滑伪距的Hatch滤波公式,利用两组实测数据进行了载波相位平滑伪距,然后将平滑后的不同观测类型的伪距用于实时差分定位。定位结果表明,C/A码Hatch滤波的差分定位精度高于P码;无电离层组合的Hatch滤波差分定位精度低于C/A码。 展开更多
关键词 全球定位系统 相位平滑伪距 HATCH滤波 DGPS P码 C/A码
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广域差分参考站两种伪距平滑算法的再评估 被引量:7
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作者 何海波 郭海荣 李保利 《测绘学院学报》 北大核心 2005年第3期157-159,共3页
广域差分GPS系统(WADGPS)参考站上,需要利用载波相位平滑伪距算法来减小多路径效应的影响.伪距平滑算法有Hatch滤波和加权Hatch滤波两种.文中基于我国WADGPS参考站的实际数据,对这两种平滑算法进行重新评估.实际数据显示,如果不能获得... 广域差分GPS系统(WADGPS)参考站上,需要利用载波相位平滑伪距算法来减小多路径效应的影响.伪距平滑算法有Hatch滤波和加权Hatch滤波两种.文中基于我国WADGPS参考站的实际数据,对这两种平滑算法进行重新评估.实际数据显示,如果不能获得可靠的伪距观测值的方差,在抑制伪距中噪声的影响方面,Hatch滤波明显优于加权Hatch滤波. 展开更多
关键词 GPS WADGPS WRS HATCH滤波 加权 HATCH滤波
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