A new method of nonlinear analysis is established by combining phase space reconstruction and data reduction sub-frequency band wavelet. This method is applied to two types of chaotic dynamic systems(Lorenz and Rssler...A new method of nonlinear analysis is established by combining phase space reconstruction and data reduction sub-frequency band wavelet. This method is applied to two types of chaotic dynamic systems(Lorenz and Rssler) to examine the anti-noise ability for complex systems. Results show that the nonlinear dynamic system analysis method resists noise and reveals the internal dynamics of a weak signal from noise pollution. On this basis, the vertical upward gas–liquid two-phase flow in a 2 mm × 0.81 mm small rectangular channel is investigated. The frequency and energy distributions of the main oscillation mode are revealed by analyzing the time–frequency spectra of the pressure signals of different flow patterns. The positive power spectral density of singular-value frequency entropy and the damping ratio are extracted to characterize the evolution of flow patterns and achieve accurate recognition of different vertical upward gas–liquid flow patterns(bubbly flow:100%, slug flow: 92%, churn flow: 96%, annular flow: 100%). The proposed analysis method will enrich the dynamics theory of multi-phase flow in small channel.展开更多
Riparian zones of channelized agricultural streams in northwestern Mississippi typically consist of narrow vegetative corridors low in habitat diversity and lacking riparian wetlands. Land clearing practices and strea...Riparian zones of channelized agricultural streams in northwestern Mississippi typically consist of narrow vegetative corridors low in habitat diversity and lacking riparian wetlands. Land clearing practices and stream channelization have led to the development of gully erosion and further fragmentation of these degraded riparian zones. Currently, installation of a gully erosion control structure (drop pipe) at the riparian zone-agricultural field interface leads to the incidental establishment of four riparian habitat types that differ in habitat area, vegetative structure, and pool size. Small mammals were sampled within four sites of each habitat type from June 1994 to July 1995. Small mammal diversity, abundance, and hispid cotton rat (Sigmodon hispidus) weight were the least within smallest Type I habitats with the least vegetative structural diversity and were the greatest within the larger Type II, III, or IV habitats having greater vegetative structural diversity and pool size. Small mammal diversity and abundance were the least in the summer 1994, increased in the fall 1994, and then declined later in our study. Hispid cotton rat abundance was the least in summer 1994, winter 1994, and spring 1995 and was the greatest in fall 1994 and summer 1995. Our results suggest that modifying the drop pipe installation design to facilitate the development of larger riparian habitats with greater vegetative structural diversity will provide the greatest benefits for small mammals.展开更多
Background: The intestinal epithelium is an important barrier that depends on a complex mixture of proteins and these proteins comprise different intercellular junctions. The purpose of this study was to investigate ...Background: The intestinal epithelium is an important barrier that depends on a complex mixture of proteins and these proteins comprise different intercellular junctions. The purpose of this study was to investigate the postnatal and developmental changes in morphology, intercellular junctions and voltage-gated potassium(Kv) channels in the intestine of piglets during the suckling and post-weaning periods.Results: Samples of the small intestine were obtained from 1-, 7-, 14-, and 21-d-old suckling piglets and piglets on d 1, 3, 5, and 7 after weaning at 14 d of age. The results showed that the percentage of proliferating cell nuclear antigen(PCNA)-positive cells and alkaline phosphatase(AKP) activity, as well as the abundances of E-cadherin,occludin, and Kv1.5 m RNA and claudin-1, claudin-3, and occludin protein in the jejunum were increased from d 1to d 21 during the suckling period(P 〈 0.05). Weaning induced decreases in the percentage of PCNA-positive cells,AKP activity and the abundances of E-cadherin, occludin and zonula occludens(ZO)-1 m RNA or protein in the jejunum on d 1, 3 and 5 post-weaning(P 〈 0.05). There were lower abundances of E-cadherin, occludin and ZO-1m RNA as well as claudin-1, claudin-3 and ZO-1 protein in the jejunum of weanling piglets than in 21-d-old suckling piglets(P 〈 0.05). The abundances of E-cadherin, occludin, ZO-1 and integrin m RNA were positively related to the percentage of PCNA-positive cells.Conclusion: Weaning at 14 d of age induced damage to the intestinal morphology and barrier. While there was an adaptive restoration on d 7 post-weaning, the measured values did not return to the pre-weaning levels, which reflected the impairment of intercellular junctions and Kv channels.展开更多
Lambert-Eaton myasthenic syndrome(LEMS) is a paraneoplastic syndrome and only 3%of small cell lung carcinoma(SCLC) patients have LEMS.Moreover,the recurrence of SCLC after a disease-free survival(DFS) of more than 10 ...Lambert-Eaton myasthenic syndrome(LEMS) is a paraneoplastic syndrome and only 3%of small cell lung carcinoma(SCLC) patients have LEMS.Moreover,the recurrence of SCLC after a disease-free survival(DFS) of more than 10 years is rare.We report a patient who had a recurrence of both SCLC and LEMS after a 13-year DFS period.A 69-year-old man was diagnosed with LEMS and SCLC(cT0N2M0,stage ⅢA) 13 years ago.Chemoradiotherapy was performed and a complete response was achieved.With anticancer treatment,the LEMS symptoms was alleviated.At the age of 82 years,gait disturbance appeared followed by left supraclavicular lymphadenopathy and further examination revealed the recurrence of SCLC.Careful screening for the recurrence of SCLC might be needed when the patient has recurrent or secondary paraneoplastic neurological syndrome even after a long DFS period.展开更多
One only needs to study the soil and geologic history and location of the ancient Mississippi and Ohio Rivers to understand why Len Small levee if patched will continue to fail. Much of Dogtooth Bend located in Alexan...One only needs to study the soil and geologic history and location of the ancient Mississippi and Ohio Rivers to understand why Len Small levee if patched will continue to fail. Much of Dogtooth Bend located in Alexander County, Illinois was originally in the ancient Ohio River valley (Figure 1) alluvial sediments north and east of the confluence with the ancient Mississippi River. The ancient Ohio River valley soils underlain by alluvial sediments and have been easily eroded by the re-aligning modern Mississippi River which now travels through the bedrock controlled Thebes Gap (Figure 2) and into the Ancient Ohio river valley. The primary objectives of this paper are: 1) to explain why Len Small levee, Alexander County, Illinois, US will continue to breach during major flooding events if repaired and 2) to develop a new combined raised causeway and levee system which will provide a Mississippi River floodwater bypass, be sustainable, encourage and fund a land use change, restore the degraded highway road beds, protect remaining Dogtooth Bend farmsteads and farmland that have not yet been degraded by past flooding events and provide floodwater storage during major flooding events at the confluence of the Mississippi and Ohio Rivers.展开更多
基金Supported by the National Natural Science Foundation of China(51406031)
文摘A new method of nonlinear analysis is established by combining phase space reconstruction and data reduction sub-frequency band wavelet. This method is applied to two types of chaotic dynamic systems(Lorenz and Rssler) to examine the anti-noise ability for complex systems. Results show that the nonlinear dynamic system analysis method resists noise and reveals the internal dynamics of a weak signal from noise pollution. On this basis, the vertical upward gas–liquid two-phase flow in a 2 mm × 0.81 mm small rectangular channel is investigated. The frequency and energy distributions of the main oscillation mode are revealed by analyzing the time–frequency spectra of the pressure signals of different flow patterns. The positive power spectral density of singular-value frequency entropy and the damping ratio are extracted to characterize the evolution of flow patterns and achieve accurate recognition of different vertical upward gas–liquid flow patterns(bubbly flow:100%, slug flow: 92%, churn flow: 96%, annular flow: 100%). The proposed analysis method will enrich the dynamics theory of multi-phase flow in small channel.
文摘Riparian zones of channelized agricultural streams in northwestern Mississippi typically consist of narrow vegetative corridors low in habitat diversity and lacking riparian wetlands. Land clearing practices and stream channelization have led to the development of gully erosion and further fragmentation of these degraded riparian zones. Currently, installation of a gully erosion control structure (drop pipe) at the riparian zone-agricultural field interface leads to the incidental establishment of four riparian habitat types that differ in habitat area, vegetative structure, and pool size. Small mammals were sampled within four sites of each habitat type from June 1994 to July 1995. Small mammal diversity, abundance, and hispid cotton rat (Sigmodon hispidus) weight were the least within smallest Type I habitats with the least vegetative structural diversity and were the greatest within the larger Type II, III, or IV habitats having greater vegetative structural diversity and pool size. Small mammal diversity and abundance were the least in the summer 1994, increased in the fall 1994, and then declined later in our study. Hispid cotton rat abundance was the least in summer 1994, winter 1994, and spring 1995 and was the greatest in fall 1994 and summer 1995. Our results suggest that modifying the drop pipe installation design to facilitate the development of larger riparian habitats with greater vegetative structural diversity will provide the greatest benefits for small mammals.
基金funded by the National Key Basic Research Program of China(2013CB127302)National Natural Science Foundation of China(31330075,31372326,31301988,31301989)+4 种基金the State Key Laboratory of Animal Nutrition(2004DA125184F1401)the Spark Program of Jiangxi Province(20142BBF061051)Changsha Lvye Biotechnology Limited Company Academician Expert WorkstationGuangdong Wangda Group Academician Workstation for Clean Feed Technology Research and Development in SwineGuangdong Hinapharm Group Academician Workstation for Biological Feed and Feed Additives and Animal Intestinal Health
文摘Background: The intestinal epithelium is an important barrier that depends on a complex mixture of proteins and these proteins comprise different intercellular junctions. The purpose of this study was to investigate the postnatal and developmental changes in morphology, intercellular junctions and voltage-gated potassium(Kv) channels in the intestine of piglets during the suckling and post-weaning periods.Results: Samples of the small intestine were obtained from 1-, 7-, 14-, and 21-d-old suckling piglets and piglets on d 1, 3, 5, and 7 after weaning at 14 d of age. The results showed that the percentage of proliferating cell nuclear antigen(PCNA)-positive cells and alkaline phosphatase(AKP) activity, as well as the abundances of E-cadherin,occludin, and Kv1.5 m RNA and claudin-1, claudin-3, and occludin protein in the jejunum were increased from d 1to d 21 during the suckling period(P 〈 0.05). Weaning induced decreases in the percentage of PCNA-positive cells,AKP activity and the abundances of E-cadherin, occludin and zonula occludens(ZO)-1 m RNA or protein in the jejunum on d 1, 3 and 5 post-weaning(P 〈 0.05). There were lower abundances of E-cadherin, occludin and ZO-1m RNA as well as claudin-1, claudin-3 and ZO-1 protein in the jejunum of weanling piglets than in 21-d-old suckling piglets(P 〈 0.05). The abundances of E-cadherin, occludin, ZO-1 and integrin m RNA were positively related to the percentage of PCNA-positive cells.Conclusion: Weaning at 14 d of age induced damage to the intestinal morphology and barrier. While there was an adaptive restoration on d 7 post-weaning, the measured values did not return to the pre-weaning levels, which reflected the impairment of intercellular junctions and Kv channels.
文摘Lambert-Eaton myasthenic syndrome(LEMS) is a paraneoplastic syndrome and only 3%of small cell lung carcinoma(SCLC) patients have LEMS.Moreover,the recurrence of SCLC after a disease-free survival(DFS) of more than 10 years is rare.We report a patient who had a recurrence of both SCLC and LEMS after a 13-year DFS period.A 69-year-old man was diagnosed with LEMS and SCLC(cT0N2M0,stage ⅢA) 13 years ago.Chemoradiotherapy was performed and a complete response was achieved.With anticancer treatment,the LEMS symptoms was alleviated.At the age of 82 years,gait disturbance appeared followed by left supraclavicular lymphadenopathy and further examination revealed the recurrence of SCLC.Careful screening for the recurrence of SCLC might be needed when the patient has recurrent or secondary paraneoplastic neurological syndrome even after a long DFS period.
文摘One only needs to study the soil and geologic history and location of the ancient Mississippi and Ohio Rivers to understand why Len Small levee if patched will continue to fail. Much of Dogtooth Bend located in Alexander County, Illinois was originally in the ancient Ohio River valley (Figure 1) alluvial sediments north and east of the confluence with the ancient Mississippi River. The ancient Ohio River valley soils underlain by alluvial sediments and have been easily eroded by the re-aligning modern Mississippi River which now travels through the bedrock controlled Thebes Gap (Figure 2) and into the Ancient Ohio river valley. The primary objectives of this paper are: 1) to explain why Len Small levee, Alexander County, Illinois, US will continue to breach during major flooding events if repaired and 2) to develop a new combined raised causeway and levee system which will provide a Mississippi River floodwater bypass, be sustainable, encourage and fund a land use change, restore the degraded highway road beds, protect remaining Dogtooth Bend farmsteads and farmland that have not yet been degraded by past flooding events and provide floodwater storage during major flooding events at the confluence of the Mississippi and Ohio Rivers.
基金the National Natural Science Foundation of China(62001478,61972435)Aviation Science Foundation Project Contract(ASFC-20165188004)+1 种基金Shanghai Aerospace Science and Technology Innovation Fund(SAST2021-035)Independent Research Fund of Key Laboratory of Military Scientific Research。
文摘无人机自主察打对地攻击场景中,针对无人机作战时效性强,地面目标识别场景复杂,存在模型训练、推理速度慢,小目标检测漏检、误检的问题,提出一种基于注意力机制与通道重排思想的无人机对地目标检测算法。该算法引入CA(coordinate attention)注意力机制,可提高网络对关注部分的特征提取能力;且对主干网络进行通道重排(channel shuffle)轻量化处理,可有效减少多次卷积造成的特征损失;最后,为提升战时训练及推理速度,替换部分激活函数为H-Swish,优化其损失函数为CIoU(complete intersection over union)。实验证明:采用改进的新算法,提升了28.4%训练速度,目标识别的平均精度均值(mean average precision, mAP)达99.1%,可实现最小目标检测为19*25像素,经TensorRT加速后检测速率达72.99 FPS,满足实时检测需求,针对复杂地形下的坦克小目标检测性能较好。