Toxic insects advertise their defended state to potential predators using warning displays. Frequently these displays use cues through more than one sensory modality, and combine color, smell and sound to produce a mu...Toxic insects advertise their defended state to potential predators using warning displays. Frequently these displays use cues through more than one sensory modality, and combine color, smell and sound to produce a multimodal warning display. Signalling through more than one sensory pathway may enhance the rate of avoidance learning, and the memorability of the learned avoidance. A common insect warning odor, pyrazine, has previously been shown to increase the rate of learned avoidance of unpalatable yellow prey by domestic chicks （GaUus gallus domesticus）, and the odor also improved memory of this learned avoidance. However, to date no research has examined this response to pyrazine odor using wild birds under natural conditions. This study used wild robins （Erithacus rubecula） to investigate whether wild birds avoided yellow baits that smelled of pyrazine more strongly than those presented with no odor. The results provide some evidence that pyrazine odor does increase the level of protection an aposematic insect gains from a wild avian predator, but that the effect of pyrazine on learned avoidance was much weaker than was found with domestic chicks .展开更多
This paper studies high order compact finite volume methods on non-uniform meshes for one-dimensional elliptic and parabolic differential equations with the Robin boundary conditions.An explicit scheme and an implicit...This paper studies high order compact finite volume methods on non-uniform meshes for one-dimensional elliptic and parabolic differential equations with the Robin boundary conditions.An explicit scheme and an implicit scheme are obtained by discretizing the equivalent integral form of the equation.For the explicit scheme with nodal values,the algebraic system can be solved by the Thomas method.For the implicit scheme with both nodal values and their derivatives,the system can be implemented by a prediction-correction procedure,where in the correction stage,an implicit formula for recovering the nodal derivatives is introduced.Taking two point boundary value problem as an example,we prove that both the explicit and implicit schemes are convergent with fourth order accuracy with respect to some standard discrete norms using the energy method.Two numerical examples demonstrate the correctness and effectiveness of the schemes,as well as the indispensability of using non-uniform meshes.展开更多
目的揭示序列相似性家族20成员b(family with sequence similarity member 20-b,Fam20b)基因在第一鳃弓间充质来源的颅颌面器官发育中的作用。方法构建Pax2-Cre;Fam20b^(f/f)小鼠,利用整体阿尔辛蓝-茜素红染色观察小鼠出生后的骨骼形态...目的揭示序列相似性家族20成员b(family with sequence similarity member 20-b,Fam20b)基因在第一鳃弓间充质来源的颅颌面器官发育中的作用。方法构建Pax2-Cre;Fam20b^(f/f)小鼠,利用整体阿尔辛蓝-茜素红染色观察小鼠出生后的骨骼形态学变化,Masson染色观察组织学特征,Ki67/TUNEL检测第一鳃弓内细胞的增殖和凋亡情况,Von-Kossa染色观察额骨矿化程度,阿尔辛蓝染色检测糖胺聚糖链(glycosaminoglycan chains,GAGs)分布范围。结果胚胎第10.5天时,Pax2-Cre;Fam20b^(f/f)小鼠下颌弓近端间充质细胞发生大量凋亡,导致该小鼠出生后表现Pierre Robin序列征(小颌畸形、舌后坠及腭裂)样表型,并伴有小颅畸形、前囟闭合不全及髁突发育不良等多种颅颌面器官畸形。组织学研究显示该小鼠额骨垂直向生长不足及矿化不良,髁突细胞外基质中GAGs的沉积减少,髁突软骨过早分化及软骨膜下成骨增加。结论在第一鳃弓间充质中敲除Fam20b导致下颌弓近端间充质细胞过度凋亡,从而造成小颌畸形。此外,抑制GAGs合成可以抑制颌面部膜内成骨,但促进软骨膜下成骨。展开更多
目的探讨Pierre Robin序列征(Pierre Robin sequence,PRS)儿童睡眠结构和呼吸特点,明确存在的潜在睡眠呼吸障碍问题,为合理诊治提供重要参考依据。方法回顾性分析2021年3月~2023年3月在首都医科大学附属北京儿童医院行多导睡眠监测(PSG)...目的探讨Pierre Robin序列征(Pierre Robin sequence,PRS)儿童睡眠结构和呼吸特点,明确存在的潜在睡眠呼吸障碍问题,为合理诊治提供重要参考依据。方法回顾性分析2021年3月~2023年3月在首都医科大学附属北京儿童医院行多导睡眠监测(PSG)的PRS儿童,分析睡眠结构及呼吸事件特点。结果共纳入36例PRS患儿,男15例,女21例,年龄中位数为1.2(1.0,1.6)岁,体重指数(BMI)为(16.8±2.1)kg/m^(2)。18例(50.0%)为原发鼾症,17例(47.2%)为轻度阻塞性睡眠呼吸暂停(OSA),1例(2.8%)为中度OSA。各类型呼吸事件中位数分别为:阻塞性呼吸暂停低通气指数为(OAHI)1.0(0.2,2.0)次/h、低通气指数(HI)为0.6(0.1,1.4)次/h、阻塞性呼吸暂停指数(OAI)为0.1(0.0,0.5)次/h、混合性呼吸暂停指数(MAI)为0.0(0.0,0.1)次/h、中枢性呼吸暂停指数(CAI)为1.7(0.6,2.5)次/h。觉醒指数中位数为9.3(7.6,11.7)次/h、最低血氧饱和度为89%。各睡眠期占总睡眠时间比例分别为,N1期15.6%±5.4%、N2期42.0%±5.5%、N3期16.5%±5.2%、R期25.9%±4.7%,睡眠效率为86.0%±6.6%。OAHI与不同睡眠期比较,差异比较无统计学意义(Z=-1.799,P>0.05)。结论PRS儿童睡眠效率下降、N1期睡眠增加,N3期睡眠减少,出现睡眠结构紊乱。同时,该类患儿存在一定程度的上气道阻塞,以轻度为主表现形式多为低通气。PSG监测可以明确呼吸事件类型,有效评估上气道阻塞程度,为临床诊治提供重要参考依据。展开更多
This paper attempts to form a bridge between a sum of the divisors function and the gamma function, proposing a novel approach that could have significant implications for classical problems in number theory, specific...This paper attempts to form a bridge between a sum of the divisors function and the gamma function, proposing a novel approach that could have significant implications for classical problems in number theory, specifically the Robin inequality and the Riemann hypothesis. The exploration of using invariant properties of these functions to derive insights into twin primes and sequential primes is a potentially innovative concept that deserves careful consideration by the mathematical community.展开更多
Properties of the gamma function are examined with implications for the Riemann hypothesis. Some new relations are obtained for the roots of the Zeta function using the properties of the Gamma function, the Bernoulli ...Properties of the gamma function are examined with implications for the Riemann hypothesis. Some new relations are obtained for the roots of the Zeta function using the properties of the Gamma function, the Bernoulli function, and limitations imposed by the rational relations of the complex roots of the Riemann zeta function, and the rational relations of the complex Gamma functions.展开更多
Dear Editor,This letter investigates the optimal denial-of-service(DoS)attack scheduling targeting state estimation in cyber-Physical systems(CPSs)with the two-hop multi-channel network.CPSs are designed to achieve ef...Dear Editor,This letter investigates the optimal denial-of-service(DoS)attack scheduling targeting state estimation in cyber-Physical systems(CPSs)with the two-hop multi-channel network.CPSs are designed to achieve efficient,secure and adaptive operation by embedding intelligent and autonomous decision-making capabilities in the physical world.As a key component of the CPSs,the wireless network is vulnerable to various malicious attacks due to its openness[1].DoS attack is one of the most common attacks,characterized of simple execution and significant destructiveness[2].To mitigate the economic losses and environmental damage caused by DoS attacks,it is crucial to model and investigate data transmissions in CPSs.展开更多
文摘Toxic insects advertise their defended state to potential predators using warning displays. Frequently these displays use cues through more than one sensory modality, and combine color, smell and sound to produce a multimodal warning display. Signalling through more than one sensory pathway may enhance the rate of avoidance learning, and the memorability of the learned avoidance. A common insect warning odor, pyrazine, has previously been shown to increase the rate of learned avoidance of unpalatable yellow prey by domestic chicks （GaUus gallus domesticus）, and the odor also improved memory of this learned avoidance. However, to date no research has examined this response to pyrazine odor using wild birds under natural conditions. This study used wild robins （Erithacus rubecula） to investigate whether wild birds avoided yellow baits that smelled of pyrazine more strongly than those presented with no odor. The results provide some evidence that pyrazine odor does increase the level of protection an aposematic insect gains from a wild avian predator, but that the effect of pyrazine on learned avoidance was much weaker than was found with domestic chicks .
文摘This paper studies high order compact finite volume methods on non-uniform meshes for one-dimensional elliptic and parabolic differential equations with the Robin boundary conditions.An explicit scheme and an implicit scheme are obtained by discretizing the equivalent integral form of the equation.For the explicit scheme with nodal values,the algebraic system can be solved by the Thomas method.For the implicit scheme with both nodal values and their derivatives,the system can be implemented by a prediction-correction procedure,where in the correction stage,an implicit formula for recovering the nodal derivatives is introduced.Taking two point boundary value problem as an example,we prove that both the explicit and implicit schemes are convergent with fourth order accuracy with respect to some standard discrete norms using the energy method.Two numerical examples demonstrate the correctness and effectiveness of the schemes,as well as the indispensability of using non-uniform meshes.
文摘目的揭示序列相似性家族20成员b(family with sequence similarity member 20-b,Fam20b)基因在第一鳃弓间充质来源的颅颌面器官发育中的作用。方法构建Pax2-Cre;Fam20b^(f/f)小鼠,利用整体阿尔辛蓝-茜素红染色观察小鼠出生后的骨骼形态学变化,Masson染色观察组织学特征,Ki67/TUNEL检测第一鳃弓内细胞的增殖和凋亡情况,Von-Kossa染色观察额骨矿化程度,阿尔辛蓝染色检测糖胺聚糖链(glycosaminoglycan chains,GAGs)分布范围。结果胚胎第10.5天时,Pax2-Cre;Fam20b^(f/f)小鼠下颌弓近端间充质细胞发生大量凋亡,导致该小鼠出生后表现Pierre Robin序列征(小颌畸形、舌后坠及腭裂)样表型,并伴有小颅畸形、前囟闭合不全及髁突发育不良等多种颅颌面器官畸形。组织学研究显示该小鼠额骨垂直向生长不足及矿化不良,髁突细胞外基质中GAGs的沉积减少,髁突软骨过早分化及软骨膜下成骨增加。结论在第一鳃弓间充质中敲除Fam20b导致下颌弓近端间充质细胞过度凋亡,从而造成小颌畸形。此外,抑制GAGs合成可以抑制颌面部膜内成骨,但促进软骨膜下成骨。
文摘目的探讨Pierre Robin序列征(Pierre Robin sequence,PRS)儿童睡眠结构和呼吸特点,明确存在的潜在睡眠呼吸障碍问题,为合理诊治提供重要参考依据。方法回顾性分析2021年3月~2023年3月在首都医科大学附属北京儿童医院行多导睡眠监测(PSG)的PRS儿童,分析睡眠结构及呼吸事件特点。结果共纳入36例PRS患儿,男15例,女21例,年龄中位数为1.2(1.0,1.6)岁,体重指数(BMI)为(16.8±2.1)kg/m^(2)。18例(50.0%)为原发鼾症,17例(47.2%)为轻度阻塞性睡眠呼吸暂停(OSA),1例(2.8%)为中度OSA。各类型呼吸事件中位数分别为:阻塞性呼吸暂停低通气指数为(OAHI)1.0(0.2,2.0)次/h、低通气指数(HI)为0.6(0.1,1.4)次/h、阻塞性呼吸暂停指数(OAI)为0.1(0.0,0.5)次/h、混合性呼吸暂停指数(MAI)为0.0(0.0,0.1)次/h、中枢性呼吸暂停指数(CAI)为1.7(0.6,2.5)次/h。觉醒指数中位数为9.3(7.6,11.7)次/h、最低血氧饱和度为89%。各睡眠期占总睡眠时间比例分别为,N1期15.6%±5.4%、N2期42.0%±5.5%、N3期16.5%±5.2%、R期25.9%±4.7%,睡眠效率为86.0%±6.6%。OAHI与不同睡眠期比较,差异比较无统计学意义(Z=-1.799,P>0.05)。结论PRS儿童睡眠效率下降、N1期睡眠增加,N3期睡眠减少,出现睡眠结构紊乱。同时,该类患儿存在一定程度的上气道阻塞,以轻度为主表现形式多为低通气。PSG监测可以明确呼吸事件类型,有效评估上气道阻塞程度,为临床诊治提供重要参考依据。
文摘This paper attempts to form a bridge between a sum of the divisors function and the gamma function, proposing a novel approach that could have significant implications for classical problems in number theory, specifically the Robin inequality and the Riemann hypothesis. The exploration of using invariant properties of these functions to derive insights into twin primes and sequential primes is a potentially innovative concept that deserves careful consideration by the mathematical community.
文摘Properties of the gamma function are examined with implications for the Riemann hypothesis. Some new relations are obtained for the roots of the Zeta function using the properties of the Gamma function, the Bernoulli function, and limitations imposed by the rational relations of the complex roots of the Riemann zeta function, and the rational relations of the complex Gamma functions.
文摘Dear Editor,This letter investigates the optimal denial-of-service(DoS)attack scheduling targeting state estimation in cyber-Physical systems(CPSs)with the two-hop multi-channel network.CPSs are designed to achieve efficient,secure and adaptive operation by embedding intelligent and autonomous decision-making capabilities in the physical world.As a key component of the CPSs,the wireless network is vulnerable to various malicious attacks due to its openness[1].DoS attack is one of the most common attacks,characterized of simple execution and significant destructiveness[2].To mitigate the economic losses and environmental damage caused by DoS attacks,it is crucial to model and investigate data transmissions in CPSs.
