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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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Heavy metal exposure reduces hatching success of Acartia pacifica resting eggs in the sediment 被引量:8
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作者 JIANG Xiao-dong WANG Gui-zhong +1 位作者 LI Shao-jing HE Jian-feng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第6期733-737,共5页
The potential effects of three heavy metals (Cu, Pb, and Cd) on hatching success ofAcartia pacifica resting eggs in the sediment of Xiamen Bay were experimentally investigated. The number ofA. pacifica nauplii hatch... The potential effects of three heavy metals (Cu, Pb, and Cd) on hatching success ofAcartia pacifica resting eggs in the sediment of Xiamen Bay were experimentally investigated. The number ofA. pacifica nauplii hatched from the sediment sharply decreased with the increase of metal concentration and exposure time from 3 to 30 d. An increase of the Cu concentration from 34.8 to 348 mg/kg, reduced the number of hatched nauplii by 46.6%-100%. An increase of the Pb concentration from 75.2 to 752 mg/kg, reduced the number of hatched nauplii by 21.4%-78.9%. An increase of the Cd concentration from 0.68 to 6.8 mg/kg, reduced the number of hatched nauplii by 31.6%-94.7%. The number of nauplii also significantly decreased with the increase of mixed-metal concentration and exposure time in the mixed-metal test. Trimmed Spearman-Karber analysis gave sediment metal 72-h LC50 values of 1.25 mmol Cu/kg, 1.73 mmol Pb/kg, and 0.054 mmol Cd/kg, which suggested that Cd was the most toxic to A. pacifica resting eggs in the three tested metals. The results indicate that heavy metals with higher concentrations can reduce recruitment of A. pacifica nauplii from benthic resting eggs to planktonic population. 展开更多
关键词 METAL resting egg hatching success Acartia pacifica
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Monochromatic green light stimulation during incubation shortened the hatching time via pineal function in White Leghorn eggs 被引量:4
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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:6
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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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Assisted Hatching in Couples with Advanced Maternal Age: A Systematic Review and Meta-analysis 被引量:2
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作者 Fan HE Chan-yu ZHANG +2 位作者 Li-si WANG Sang-lin LI Li-na HU 《Current Medical Science》 SCIE CAS 2018年第3期552-557,共6页
This systematic review aimed to evaluate the efficacy and safety of assisted hatching (AH) performed in couples with advanced maternal age. We searched for randomized controlled trials (RCTs) in electronic databas... This systematic review aimed to evaluate the efficacy and safety of assisted hatching (AH) performed in couples with advanced maternal age. We searched for randomized controlled trials (RCTs) in electronic databases, including MEDLINE, EMBASE and CENTRAL (from inception to January 2018); in addition, we hand-searched the reference lists of included studies and similar reviews. We included RCTs comparing AH versus no treatment (control). The meta-analysis was performed by RevMan 5.3 software. The search retrieved 943 records and 8 RCTs were included, comprising 870 cycles (n=440 for AH, and n=430 for control). There was no significant difference in the rates of live birth (RR 0.88, 95% CI 0.65 to 1.18, 3 RCTs, n-427,I^2=0%), clinical pregnancy (RR 1.00, 95% CI 0.83 to 1.19, 8 RCTs, n=870, I^2=22%), implantation (RR 1.07, 95% CI 0.83 to 1.39, 4 RCTs, n=1359, I^2=0%), miscarriage (RR 1.13, 95% CI 0.66 to 1.94, 2 RCTs, n=116, I^2=0%) and multiple pregnancy (RR 0.89, 95% CI 0.31 to 2.52, 1 RCT, n=97,I^2=not applicable) between the treatment group and control group. No reasonable conclusions could be drawn regarding reproductive outcomes after AH in patients with advanced maternal age due to the small sample pooled in meta-analyses. Studies of high methodological quality and with adequate power are necessary to further investigate the value of AH in assisted conception of those patients. 展开更多
关键词 assisted hatching advanced maternal age in vitro fertilization frozen-thawed embryo transfer
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The effect of the causative algae of large-scale HAB in the East China Sea on egg hatching of Argopecten irradians, and population growth of Brachionus plicatilis and Moina mongolica 被引量:2
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作者 CHEN Taoying YAN Tian +2 位作者 WANG Liping ZHANG Bin ZHOU Mingjiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第4期112-122,共11页
The impacts of Prorocentrum donghaiense Lu and Alexandrium catenella Balech, causative species of the large-scale HAB in the East China Sea, were studied under laboratory conditions. According to bloom densities, the ... The impacts of Prorocentrum donghaiense Lu and Alexandrium catenella Balech, causative species of the large-scale HAB in the East China Sea, were studied under laboratory conditions. According to bloom densities, the effects of monocuhure and mixture of the two species were examined on the egg-hatching success ofArgopecten irradiarts Lamarck, and the population growth of Brachionus plicatilis MUller and Moina mongolica Daday. The results showed that monocuhure of A. catenella had a significant inhibition on the egg hatching success of A. irradians, and the population growth of B. plicatilis and M. mongolica. The median effective densities (ED50) inhibiting the egg hatching success of A. irradhms for 24 h and the population growth of B. plicatilis and M. mongolica for 96 h were 800, 630, and 2 400 cells/cm^3 , respectively. Monoculture of P. dongha/ense has no such inhibitory effect on the egg hatching success of A. irradians; P. donghaiense at lower suitable densities could sustain the population growth of B. plicatilis ( 1 × 10^4 ~ 3 ×10^4 cells/cm^3 ) and M. mongolica (2 × 10^4~5 ×10^4 cells/cm^3 ) ; P. donghaiense at higher densities had significantly adverse effect on the population growth of B. plicatilis (4 × 10^4 ~ 10×10^4 cells/cm^3 ) and M. mongolica ( 10 ×10^4 cells/cm^3). When the two algae were mixed according to bloom densities, P. donghaiense at suitable densities to some extent could decrease the toxicity of A. catenella to B. plicatilis and M. mongolica. The results indicated that the large-scale HAB in the East China Sea could have adverse effect on zooplankton, and might further influence the marine ecosystem, especially when there was also Alexandrium bloom. 展开更多
关键词 harmful algal blooms Argopecten irradians egg hatching Brachionus plicatilis Moina mongolica population growth
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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
Effects of lanthanum on egg hatching and nauplius metamorphosis of Penaeus chinensis(P. chinensis) were studied. The experimental results showed that the optimum concentration of lanthanum was 0 30~1 80 mg/L fo... Effects of lanthanum on egg hatching and nauplius metamorphosis of Penaeus chinensis(P. chinensis) were studied. The experimental results showed that the optimum concentration of lanthanum was 0 30~1 80 mg/L for monocell and dicell stage of embryo development, the egg hatching rates were raised by 33 5%~49 1%; and it was 0 90~1 80 mg/L for poly cell stage, the egg hatching rate was raised by 17 1%~23 5%. The optimum concentration was 0 90~1 50 mg/L for nauplius metamorphosis, the metamorphosis rate from nauplius(N 1) to protozoea(Z 1) was raised by 9 4%~11 7%. The promotion of lanthanum to egg embryo development was completed through absorption of lanthanum by egg in the water. The absorption capacity of one egg for lanthanum was 5 89 μg. 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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A Study on Artificial Hatching of Chinese Bombyx mandarina Moore
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作者 ZHAO Hua-qiang XU Ya-xiang +4 位作者 WANG Dong LI Bing WEI Zheng-guo CHEN Yu-hua SHEN Wei-de 《Agricultural Sciences in China》 CAS CSCD 2008年第4期502-506,共5页
Diapause eggs of Bombyx mandarina Moore from Wujiang, Jiangsu Province, China, were used to study the artificial hatching of B. mandarina Moore. The results showed that the highest hatchability was obtained by instant... Diapause eggs of Bombyx mandarina Moore from Wujiang, Jiangsu Province, China, were used to study the artificial hatching of B. mandarina Moore. The results showed that the highest hatchability was obtained by instant treatment with hydrochloric acid (HC1, specific gravity 1.065-1.075) for 5 rain under 46℃. After the B. mandarina eggs were cold stored at 5℃ for 40 days, the highest hatchability was obtained by treatment with HC1 (specific gravity 1.092) for 6 minutes under 47.8℃. For the B. mandarina eggs that were stored at 25℃ for 28 d and then cold-stored at 5℃ for 0-100 days, the highest hatchability was obtained by treatment with HCI (specific gravity 1.092) for 6 rain at 47.8℃. The longer the cold storage period, the higher was the hatchability. Acid treatment on diapause eggs of B. mandarina for 6 rains at 47.8℃ with hydrochloric acid (specific gravity 1.092) before hatching in spring could obviously shorten the hatching stage and increase the hatchability. 展开更多
关键词 Bombyx mandarina Moore artificial hatching instant acid treatment acid treatment after chilling acidtreatment on diapause eggs after chilling
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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
A new method was used to remove heavy metals in sea water. The requirement of copper in sea water ofegg hatching and naupliar metamorphosis of Penaeus chinensis was investored. A certain amount of copper ion andchelat... A new method was used to remove heavy metals in sea water. The requirement of copper in sea water ofegg hatching and naupliar metamorphosis of Penaeus chinensis was investored. A certain amount of copper ion andchelator nitrilotriacetic acid (NTA) were added in the de-heavy-metal-ionized sea water and then the cupric ion actvitywas calculated. The effects of copper ion on egg hatching and naupliar metamorphosis were observed. It was firstfound by experiments that trace ionic copper (10-10.80-10-8.80 mol/dm3) was essential to the growth and development of egg and nauplii of penaeid shrimp and chelated copper had no actions for these living processes,but in highconcentrations (>10 -7.80 mol/dm3) ionic copper was toxic. The nauplii were more sensitive to necessity and tokicityof ionic copper than eggs. 展开更多
关键词 Egg hatching copper ion Penaeus chinensis naupliar metamorphosis
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Effect of an Improved Mechanical Method for Assisted Hatching on the in vitro Development of Mouse Embryos
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作者 Ai-jun ZHANG Yun FENG Xiao-yan HUANG Lan XLA Yi-juan SUN Yan LI 《Journal of Reproduction and Contraception》 CAS 2006年第1期23-28,共6页
Objective To evaluate the safety and efficiency of an improved shape of opening for mechanical assisted hatching (AH) on the in virto development of mouse embryos. Methods A total of 622 KM BAI mouse embryos in 2-... Objective To evaluate the safety and efficiency of an improved shape of opening for mechanical assisted hatching (AH) on the in virto development of mouse embryos. Methods A total of 622 KM BAI mouse embryos in 2-cell-4-cell stage were randomly divided into group A, group B and control group. A new mechanical AH method by improving the shape of opening in the ZP was used in group A, and a "-/ "-shaped opening was created. A "+ " -shaped opening was made in group B, while no opening was made in control group. Comparisons have been made among the three groups with regard to the duration of AH, the blastocyst formation and complete hatching rate, etc. Results The duration of AH in group A (43.25 ±3.46 s) was significantly shorter than that in group B (52.81 ±4.32 s, P 〈0.05). The blastocyst formation rate on d 5 was not significantly different among the three groups (92.27%, 93.66% and 94.92% respectively, P 〉0.05). The complete hatching rate of blastocysts on d 6 between group A and group B was no statistical difference (94.09% vs 92.71%, P 〉0.05), but significantly higher than that in control group (43.32%, P 〈0.001). No significant difference in the percentage of grade 1 blastocysts was found among the three groups on d 5 (85.22%, 82.81% and 86.63% respectively, P 〉0.05). Conclusion R could enhance the process of embryo hatching and facilitate the hatching rate of blastocysts by using the improved mechanical AH method, which is of safety and efficiency to mouse embryo in the in vitro development. 展开更多
关键词 assisted hatching mouse embryo in vitro development
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Ecological Hatching Method for Misgurnus anguillicaudatus Fingerlings
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作者 Liang Shaomin Li Chunfa Zhang Xiaolei 《Animal Husbandry and Feed Science》 CAS 2015年第1期25-26,45,共3页
[Objective]To improve the artificial propagation technique of Misgurnus anguillicaudatus,and to provide technical support for the industrialization development of M.anguillicaudatus in future.[Methods] The hatching ra... [Objective]To improve the artificial propagation technique of Misgurnus anguillicaudatus,and to provide technical support for the industrialization development of M.anguillicaudatus in future.[Methods] The hatching rates,survival rates,deformity rates and parent morality rates of M.anguillicaudatus were compared by ecological hatching method and traditional hatching method.[Results]The hatching rate by ecological hatching method was 32.60% higher than that by traditional hatching method,showing extremely significant differences.The survival rate of M.anguillicaudatus fingerlings by ecological hatching method was2.32% higher than that by traditional hatching method.And the deformity rates of M.anguillicaudatus fingerlings by traditional hatching method and ecological hatching method were 26.50% and 24.14%,respectively,indicating no significant differences.The morality rates of female parents of M.anguillicaudatus were89.72% and 5.91% by traditional hatching method and ecological hatching method,respectively.[Conclusions]Ecological hatching method effectively improved the hatching rate and fingerling survival rate of M.anguillicaudatus,and reduced the morality rate of female parents,which was helpful to save the production cost,met the requirements for large-scale production of M.anguillicaudatus,and had good application prospect. 展开更多
关键词 hatching rate Survival rate Deformity rate Morality rate
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Hatching Hope
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作者 Li Jing 《ChinAfrica》 2018年第11期32-33,共2页
Sindayigaya Evariste, owner of Safe Chicken Farm in the suburb of Bujumbura, capital of Burundi, felt nervous each time his hens hatched chicks. Though he and his workers tried to provide the best environment for the ... Sindayigaya Evariste, owner of Safe Chicken Farm in the suburb of Bujumbura, capital of Burundi, felt nervous each time his hens hatched chicks. Though he and his workers tried to provide the best environment for the hens, only a small portion of chicks would hatch. In Burundi, there are many other poultry. farmers like Evariste who are suffering without artificial hatching technologies and have to rely on hens to hatch chicks. 展开更多
关键词 hatching Hope
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基于Hatch滤波的改进矩阵变换法在BDS多频模糊度解算中的应用
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作者 刘国超 姜凯华 +1 位作者 黄文嘉 张莹 《工程勘察》 2024年第7期49-54,共6页
长基线条件下,空间相关性弱,电离层延迟残差和噪声影响变大,致使矩阵变换法模糊度解算过程中,窄巷组合受噪声影响大,单历元模糊度解算成功率低。因此,削弱电离层残差及噪声影响可以一定程度提高模糊度解算成功率。本文在分析矩阵变换算... 长基线条件下,空间相关性弱,电离层延迟残差和噪声影响变大,致使矩阵变换法模糊度解算过程中,窄巷组合受噪声影响大,单历元模糊度解算成功率低。因此,削弱电离层残差及噪声影响可以一定程度提高模糊度解算成功率。本文在分析矩阵变换算法基础上,利用Hatch滤波有效抑制伪距测量噪声和多径效应特点,结合弱电离层、低噪声的载波组合,通过相位平滑伪距代替组合伪距值参与解算,从而削弱电离层残差及观测噪声影响。通过实测数据分析,本文算法可有效提高矩阵变换法模糊度解算成功率。 展开更多
关键词 模糊度 BDS HATCH滤波 矩阵变换 载波相位平滑伪距
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Effects of copper, lead and zinc in soil on egg development and hatching of Folsomia candida 被引量:4
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作者 Jie Xu Yin Wang +2 位作者 Yong-Ming Luo Jing Song Xin Ke 《Insect Science》 SCIE CAS CSCD 2009年第1期51-55,共5页
Effects of CaCl2, CuCl2, ZnCl2 and PbCl2 on development and hatching success of eggs of Folsomia candida (Collembola) were studied under laboratory conditions. Thousands of healthy eggs from synchronized cultures we... Effects of CaCl2, CuCl2, ZnCl2 and PbCl2 on development and hatching success of eggs of Folsomia candida (Collembola) were studied under laboratory conditions. Thousands of healthy eggs from synchronized cultures were incubated in soils treated with different concentrations of the metals. Compared with the water control, egg hatch significantly decreased when concentrations of Cu, Pb and Zn reached 400, 1 600 and 800 mg/kg dry soil, respectively. Values of EC50(hatching), calculated according to the exponential model (with 95% confidence limits in brackets), were 625 (407-875), 2 361 (2 064-2 687) and 1 763 (1 548-2 000) mg/kg dry soils for Cu, Pb and Zn, respectively. When Cu concentration reached 1 600 mg/kg dry soil, eggs became green and the percentage of green eggs changed from 5%-20% after incubation for 2 days to 15%- 30% after incubation for 4 days. At 3 200 mg Cu/kg dry soil, tissues inside eggs were black and shrunken. 展开更多
关键词 metal pollution soil springtail hatching success METAMORPHOSIS toxicity test ultrathin sectioning
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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 (Carassius auratus auratus) and loach (Paramisgurnus dabryanus (sauvage)) cytulas were studied. The ultrasound with certain frequencies can accelerate the deve... The effects of ultrasound on the hatching of the goldfish (Carassius auratus auratus) and loach (Paramisgurnus dabryanus (sauvage)) cytulas were studied. The ultrasound with certain frequencies can accelerate the development of cytulas, induce the embryos to break membrane earlier, increase the survival rate of larvas, and increase 50% hatching rate of loach cytulas at lower temperature. 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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