[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
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
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
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
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
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
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
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
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
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
基金Supported by National Innovation and Entrepreneurship Program for College Students(201910223022)Daqing"Jiebangguashuai"Science and Technology Key Project in the New Energy Field(2021BD05)。
文摘[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.
基金Financial support of this study was provided by The National Key Research and Development Program of China(grant number 2016YFD0500502)China Agriculture Research Systems(grant number CARS-40)+1 种基金Fundamental Research Funds for Central Non-profit Scientific Institution(grant number 2018-YWF-YB-20)Agricultural Science and Technology Innovation Program(grant number ASTIP-IAS04).
文摘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.
文摘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
文摘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.
基金This work was supported by Special Fund for Agro-scientific Research in the Public Interest(Grant No.201303084)。
文摘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.
文摘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.
基金This work is supported by National Natural Science Foundation of China
文摘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.
基金supported by the National Natural Science Foundation of China(NSFC,31971413)granted to DLthe Second Tibetan Plateau Scientific Expedition and Research Program(STEP,2019QZKK0501)granted to DL。
文摘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.
基金This work was supported by grants from the Special Foundation for Basic Work of the Science and Technology Ministry of China(2022FY100500-2)Hainan Key Program of Science and Technology(ZDXM20110008)Hainan Specially Supporting Discipline of Zoology。
文摘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.
文摘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。