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Robust Facial Biometric Authentication System Using Pupillary Light Reflex for Liveness Detection of Facial Images
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作者 Puja S.Prasad Adepu Sree Lakshmi +5 位作者 Sandeep Kautish Simar Preet Singh Rajesh Kumar Shrivastava Abdulaziz S.Almazyad Hossam M.Zawbaa Ali Wagdy Mohamed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期725-739,共15页
Pupil dynamics are the important characteristics of face spoofing detection.The face recognition system is one of the most used biometrics for authenticating individual identity.The main threats to the facial recognit... Pupil dynamics are the important characteristics of face spoofing detection.The face recognition system is one of the most used biometrics for authenticating individual identity.The main threats to the facial recognition system are different types of presentation attacks like print attacks,3D mask attacks,replay attacks,etc.The proposed model uses pupil characteristics for liveness detection during the authentication process.The pupillary light reflex is an involuntary reaction controlling the pupil’s diameter at different light intensities.The proposed framework consists of two-phase methodologies.In the first phase,the pupil’s diameter is calculated by applying stimulus(light)in one eye of the subject and calculating the constriction of the pupil size on both eyes in different video frames.The above measurement is converted into feature space using Kohn and Clynes model-defined parameters.The Support Vector Machine is used to classify legitimate subjects when the diameter change is normal(or when the eye is alive)or illegitimate subjects when there is no change or abnormal oscillations of pupil behavior due to the presence of printed photograph,video,or 3D mask of the subject in front of the camera.In the second phase,we perform the facial recognition process.Scale-invariant feature transform(SIFT)is used to find the features from the facial images,with each feature having a size of a 128-dimensional vector.These features are scale,rotation,and orientation invariant and are used for recognizing facial images.The brute force matching algorithm is used for matching features of two different images.The threshold value we considered is 0.08 for good matches.To analyze the performance of the framework,we tested our model in two Face antispoofing datasets named Replay attack datasets and CASIA-SURF datasets,which were used because they contain the videos of the subjects in each sample having three modalities(RGB,IR,Depth).The CASIA-SURF datasets showed an 89.9%Equal Error Rate,while the Replay Attack datasets showed a 92.1%Equal Error Rate. 展开更多
关键词 SIFT PUPIL CASIA-SURF pupillary light reflex replay attack dataset brute force
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Is there a need for universal double reflex testing of HBsAg-positive individuals for hepatitis D infection?
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作者 Zaigham Abbas Minaam Abbas 《World Journal of Hepatology》 2024年第3期300-303,共4页
Hepatitis D virus(HDV)can infect HBsAg-positive individuals,causing rapid fibrosis progression,early decompensation,increased hepatocellular carcinoma risk,and higher mortality than hepatitis B virus(HBV)mono-infectio... Hepatitis D virus(HDV)can infect HBsAg-positive individuals,causing rapid fibrosis progression,early decompensation,increased hepatocellular carcinoma risk,and higher mortality than hepatitis B virus(HBV)mono-infection.Most countries lack high-quality HDV prevalence data,and the collection techniques employed often bias published data.In recent meta-analyses,HDV prevalence in HBsAg-positive patients reaches 5%-15%and is even significantly higher in endemic areas.Since HBV vaccination programs were implemented,HDV prevalence has decreased among younger populations.However,owing to immigrant influx,it has increased in some Western countries.The current practice of HDV screening in HBsAg-positive individuals is stepwise,based on physician’s discretion,and limited to at-risk populations and may require numerous visits.Double reflex testing,which includes anti-HDV testing in all HBsAg-positive individuals and then HDV RNA testing for anti-HDV-positive ones,is uncommon.Reflex testing can identify more HDV infection cases and link identified patients to further care and follow-up.Moreover,laboratory-based double reflex screening is less biased than physician-led testing.Therefore,health-care providers should learn about reflex testing,and federal and provincial hepatitis control programs should implement laboratory-based double reflex testing to obtain reliable HDV prevalence estimates.The test’s cost-effectiveness depends on the number of HBV-positive patients screened to identify one HDV-positive patient.Such testing may be viable in areas with low HBsAg but high HDV prevalence.However,its economic impact on areas with low HDV prevalence needs further study. 展开更多
关键词 Anti-hepatitis D virus antibody HBSAG Hepatitis D virus RNA Hepatitis B Hepatitis D reflex testing
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Nursing Care of 10 Patients with Vasovagal Reflex Caused by Artificial Liver Support System Treatment
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作者 Yingying Zhang 《Open Journal of Nursing》 2024年第5期177-182,共6页
This study outlines the essential nursing strategies employed in the care of 10 patients experiencing vascular vagal reflex, managed with artificial liver support systems. It highlights a holistic nursing approach tai... This study outlines the essential nursing strategies employed in the care of 10 patients experiencing vascular vagal reflex, managed with artificial liver support systems. It highlights a holistic nursing approach tailored to the distinct clinical manifestations of these patients. Key interventions included early detection of psychological issues prior to initiating treatment, the implementation of comprehensive health education, meticulous monitoring of vital signs throughout the therapy, prompt emergency interventions when needed, adherence to prescribed medication protocols, and careful post-treatment observations including venous catheter management. Following rigorous treatment and dedicated nursing care, 7 patients demonstrated significant improvement and were subsequently discharged. 展开更多
关键词 Vasovagal reflex Artificial Liver Support System Nursing Care
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Alterations in blink and masseter reflex latencies in older adults with neurocognitive disorder and/or diabetes mellitus
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作者 Jaime Alberto Bricio-Barrios Eder Ríos-Bracamontes +7 位作者 Mónica Ríos-Silva Miguel Huerta Walter Serrano-Moreno JoséEnrique Barrios-Navarro Genaro Gabriel Ortiz Miguel Huerta-Trujillo JoséGuzmán-Esquivel Xóchitl Trujillo 《World Journal of Clinical Cases》 SCIE 2022年第1期177-188,共12页
BACKGROUND Blink and masseter reflexes provide reliable,quantifiable data on the function of the central nervous system:Delayed latencies have been found in patients with neurocognitive disorder(ND)and type 2 diabetes... BACKGROUND Blink and masseter reflexes provide reliable,quantifiable data on the function of the central nervous system:Delayed latencies have been found in patients with neurocognitive disorder(ND)and type 2 diabetes mellitus(T2DM),but this has not been studied in patients with both pathologies.AIM To investigate if older adults with ND plus T2DM have prolonged latencies of blink and masseter-reflex and if they were associated with disease progression.METHODS This cross-sectional study included 227 older adults(>60 years)from Colima,Mexico.Neurocognitive disorder was identified by a neuropsychological battery test,and T2DM identified by medical history,fasting glucose,and glycosylated hemoglobin.Latencies in the early reflex(R1),ipsilateral late(R2),and contralateral late(R2c)components of the blink reflex were analyzed for all subjects,and 183 subjects were analyzed for latency of the masseter reflex.RESULTS In 20.7%of participants,ND was detected.In 37%,T2DM was detected.Latencies in R1,R2,and R2c were significantly prolonged for groups with ND plus T2DM,ND,and T2DM,compared with the control group(P<0.0001).The masseter reflex was only prolonged in older adults(regardless of T2DM status)with ND vs controls(P=0.030).In older adults with ND and without T2DM,the more the cognitive impairment progressed,the more prolonged latencies in R2 and R2c presented(P<0.01).CONCLUSION These findings suggest that blink and masseter reflexes could be used to evaluate possible changes in brainstem circuits in older adults with ND and T2DM. 展开更多
关键词 Blink reflex Masseter reflex Brainstem reflexes Neurocognitive disorder Type 2 diabetes mellitus Older adults
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Reflexive solution to a system of matrix equations 被引量:2
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作者 常海霞 王卿文 《Journal of Shanghai University(English Edition)》 CAS 2007年第4期355-358,共4页
We derive necessary and sufficient conditions for the existence and an expression of the (anti)reflexive solution with respect to the nontrivial generalized reflection matrix P to the system of complex matrix equati... We derive necessary and sufficient conditions for the existence and an expression of the (anti)reflexive solution with respect to the nontrivial generalized reflection matrix P to the system of complex matrix equations AX = B and XC = D. The explicit solutions of the approximation problem min x∈Ф ||X - E||F was given, where E is a given complex matrix and Ф is the set of all reflexive (or antireflexive) solutions of the system mentioned above, and ||·|| is the Frobenius norm. Furthermore, it was pointed that some results in a recent paper are special cases of this paper. 展开更多
关键词 system of matrix equations Moore-Penrose inverse reflexive matrix antireflexive matrix Frobenius norm
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REFLEX自锁钢板治疗颈椎间盘突出的临床疗效
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作者 施克勤 陶波 《齐齐哈尔医学院学报》 2004年第6期621-622,共2页
目的 探讨应用REFLEX颈椎前路自锁钢板治疗颈椎间盘突出的远期疗效。方法  4 6例患者经前路减压植骨融合REFLEX自锁钢板固定。结果  4 4例患者获得长期随访 ,最长 2 3个月 ,最短 14个月 ,平均 17个月。所有患者均于 13~ 16周获得骨... 目的 探讨应用REFLEX颈椎前路自锁钢板治疗颈椎间盘突出的远期疗效。方法  4 6例患者经前路减压植骨融合REFLEX自锁钢板固定。结果  4 4例患者获得长期随访 ,最长 2 3个月 ,最短 14个月 ,平均 17个月。所有患者均于 13~ 16周获得骨性愈合。术后未出现椎间高度丢失现象 ,无钢板螺钉松动 ,植骨块滑脱。获得随访病例绝大多数神经功能得到不同程度的改善。结论 应用RE 展开更多
关键词 reflex自锁钢板 颈椎间盘突出 前路减压 神经功能
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ON TOPOLOGICAL REFLEXIVITY OF THE SPACES OF DERIVATIONS ON OPERATOR ALGEBRAS
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作者 Jing Wu Lu Shijie Han GuangguoDept. of Math.,Zhejiang Univ.,Hangzhou 310027. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第1期75-79,共5页
It is proved that the spaces of derivations on some operator algebras are topologically reflexive in the weak operator topology.
关键词 DERIVATION reflexIVITY von Neumann algebra reflexive algebra.
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Unilateral Reference Values for Hoffmann’s Reflex in Patients with Suspected Lumbosacral Radiculopathies
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作者 I-Hsuan Tsai Hao-Hsuan Tsai 《Open Journal of Orthopedics》 2013年第3期178-182,共5页
Unilateral reference values for Hoffmann’s amplitude could be applied to the diagnosis of lumbosacral radiculopathy, especially in patients with bilateral lesions. Here, we assessed Hoffmann’s reflex by measuring H-... Unilateral reference values for Hoffmann’s amplitude could be applied to the diagnosis of lumbosacral radiculopathy, especially in patients with bilateral lesions. Here, we assessed Hoffmann’s reflex by measuring H-wave amplitude and the ratio of H-wave amplitude to M-wave amplitude (the H/M ratio). We performed a cross-sectional survey of patients from a Taiwan rehabilitation center (n = 64, age 20 - 87) who presented with lower back pain that radiated to the leg and received a referral for electrodiagnostic examinations. Reference values for H-wave profile parameters were determined using data from lumbosacral radiculopathy-negative patients (n = 10, age 22 - 53), who had normal big toe test results, ankle reflex test results, motor and sensory nerve conductive studies and F-wave latency and who displayed no evidence of radiculopathy in electromyography and imaging studies. The 50th percentile values for H/M ratio and H-wave amplitude were 28% and 6.25 mV, respectively. An H-wave profile th percentile (H/M ratio bosacral radiculopathy (n = 64). Approximately 41% of patients with an H-wave profile th percentile showed electromyography-confirmed chronic radiculopathy. Electromyography-confirmed current radiculopathy was observed in 35% of patients with an H/R 展开更多
关键词 Hoffmann’s reflex H-reflex Electromyography Electrodiagnostic Studies LUMBOSACRAL RADICULOPATHY SCIATICA
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On Edge Irregular Reflexive Labeling of Categorical Product of Two Paths
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作者 Muhammad Javed Azhar Khan Muhammad Ibrahim Ali Ahmad 《Computer Systems Science & Engineering》 SCIE EI 2021年第3期485-492,共8页
Among the huge diversity of ideas that show up while studying graph theory,one that has obtained a lot of popularity is the concept of labelings of graphs.Graph labelings give valuable mathematical models for a wide s... Among the huge diversity of ideas that show up while studying graph theory,one that has obtained a lot of popularity is the concept of labelings of graphs.Graph labelings give valuable mathematical models for a wide scope of applications in high technologies(cryptography,astronomy,data security,various coding theory problems,communication networks,etc.).A labeling or a valuation of a graph is any mapping that sends a certain set of graph elements to a certain set of numbers subject to certain conditions.Graph labeling is a mapping of elements of the graph,i.e.,vertex and for edges to a set of numbers(usually positive integers),called labels.If the domain is the vertex-set or the edge-set,the labelings are called vertex labelings or edge labelings respectively.Similarly,if the domain is V(G)[E(G)],then the labeling is called total labeling.A reflexive edge irregular k-labeling of graph introduced by Tanna et al.:A total labeling of graph such that for any two different edges ab and a'b'of the graph their weights has wt_(x)(ab)=x(a)+x(ab)+x(b) and wt_(x)(a'b')=x(a')+x(a'b')+x(b') are distinct.The smallest value of k for which such labeling exist is called the reflexive edge strength of the graph and is denoted by res(G).In this paper we have found the exact value of the reflexive edge irregularity strength of the categorical product of two paths (P_(a)×P_(b))for any choice of a≥3 and b≥3. 展开更多
关键词 Edge irregular reflexive labeling reflexive edge strength categorical product of two paths
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Strongly s-Reflexive Rings Relative to a Monoid
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作者 PENG Zhai-ming GU Qin-qin ZHANG Rui-rui 《Chinese Quarterly Journal of Mathematics》 2018年第3期260-271,共12页
For a monoid M and an endomorphism α of a ring R, we introduce the notion of strongly M-α-reflexive rings and study its properties. For an u.p.-monoid M and a right Ore ring R with its classical right quotient ring ... For a monoid M and an endomorphism α of a ring R, we introduce the notion of strongly M-α-reflexive rings and study its properties. For an u.p.-monoid M and a right Ore ring R with its classical right quotient ring Q, we prove that R is strongly M-α-reflexive if and only if Q is strongly M-α-reflexive, where R is α-rigid, α is an epimorphism of R. The relationship between some special subrings of upper triangular matrix rings and strongly M-α-reflexive rings is also investigated. Several known results similar to strongly M-α-reversible rings are obtained. 展开更多
关键词 Unique product MONOID a-reflexive RING STRONGLY M-a-reflexive RING strictlytotally ORDERED MONOID
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用Reflexive ACL实现网络单向访问
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作者 张昆朋 《现代计算机》 2006年第8期30-31,52,共3页
通过建立路由器访问控制列表,可以控制任何IP地址对网络的访问,但要实现网络的单向访问,一般的访问列表是无法做到的。本文从实际应用的角度出发,利用一种特殊的ACL-ReflexiveACL,即自反访问控制列表,来实现网络的单向访问,并分析、阐... 通过建立路由器访问控制列表,可以控制任何IP地址对网络的访问,但要实现网络的单向访问,一般的访问列表是无法做到的。本文从实际应用的角度出发,利用一种特殊的ACL-ReflexiveACL,即自反访问控制列表,来实现网络的单向访问,并分析、阐述了它的配置过程。 展开更多
关键词 reflexIVE ACL 路由器 单向访问
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Nilpotent Elements and Nil-Reflexive Property of Generalized Power Series Rings
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作者 Eltiyeb Ali 《Advances in Pure Mathematics》 2022年第11期676-692,共17页
Let R be a ring and (S,≤) a strictly ordered monoid. In this paper, we deal with a new approach to reflexive property for rings by using nilpotent elements, in this direction we introduce the notions of generalized p... Let R be a ring and (S,≤) a strictly ordered monoid. In this paper, we deal with a new approach to reflexive property for rings by using nilpotent elements, in this direction we introduce the notions of generalized power series reflexive and nil generalized power series reflexive, respectively. We obtain various necessary or sufficient conditions for a ring to be generalized power series reflexive and nil generalized power series reflexive. Examples are given to show that, nil generalized power series reflexive need not be generalized power series reflexive and vice versa, and nil generalized power series reflexive but not semicommutative are presented. We proved that, if R is a left APP-ring, then R is generalized power series reflexive, and R is nil generalized power series reflexive if and only if R/I is nil generalized power series reflexive. Moreover, we investigate ring extensions which have roles in ring theory. 展开更多
关键词 Left APP-Ring Generalized Power Series reflexive Ring Nil Generalized Power Series reflexive Ring S-Quasi Armendariz Ring Semiprime Ring Semicommutative Ring
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Electroacupuncture at ST36 modulates gastric motility via vagovagal and sympathetic reflexes in rats 被引量:14
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作者 Meng-Jiang Lu Zhi Yu +2 位作者 Yan He Yin Yin Bin Xu 《World Journal of Gastroenterology》 SCIE CAS 2019年第19期2315-2326,共12页
BACKGROUND Electroacupuncture(EA) at ST36 can significantly improve gastrointestinal symptoms, especially in promoting gastrointestinal motility. The automatic nervous system plays a main role in EA, but few studies e... BACKGROUND Electroacupuncture(EA) at ST36 can significantly improve gastrointestinal symptoms, especially in promoting gastrointestinal motility. The automatic nervous system plays a main role in EA, but few studies exist on how vagovagal and sympathetic reflexes affect EA to regulate gastrointestinal motility.AIM To study the role of vagovagal and sympathetic reflexes in EA at ST36, as well as the associated receptor subtypes that are involved.METHODS Gastric motility was measured with a manometric balloon placed in the gastric antrum area in anesthetized animals. The peripheral nervous discharge was measured using a platinum electrode hooking the vagus or greater splanchnic nerve, and the central nervous discharge was measured with a glass microelectrode in the dorsal motor nucleus of the vagus(DMV). The effects and mechanisms of EA at ST36 were explored in male Sprague-Dawley rats which were divided in to a control group, vagotomy group, sympathectomy group, and microinjection group [including an artificial cerebrospinal fluid group, glutamate(L-Glu) group, and γ-aminobutyric acid(GABA) group] and in genetically modified male mice [β1β2 receptor-knockout(β1β2^(-/-)) mice, M2M3 receptorknockout(M2M3^(-/-)) mice, and wild-type control mice].RESULTS EA at ST36 promoted gastric motility during 30-120 s. During EA, both vagus and sympathetic nerve discharges increased, with a much higher frequency of vagus nerve discharge than sympathetic discharge. The gastric motility mediated by EA at ST36 was interdicted by vagotomy. However, gastric motility mediated by EA at ST36 was increased during 0-120 s by sympathectomy, which eliminated the delay effect of EA during 0-30 s, but it was lower than the control group during 30-120 s. Using gene knockout mice and their wild-type controls to explore the receptor mechanisms, we found that EA at ST36 decreased gastric motility in M2/3^(-/-) mice, and promoted gastric motility in β1/2^(-/-) mice. Extracellular recordings showed that EA at ST36 increased spikes of the DMV. Microinjection of L-Glu into the DMV increased gastric motility, while EA at ST36 decreased gastric motility during 0-60 s, and promoted gastric motility during 60-120 s.Injection of GABA reduced or increased gastric motility, and reduced the promoting gastric motility effect of EA at ST36.CONCLUSION These data suggest that EA at ST36 modulates gastric motility via vagovagal and sympathetic reflexes mediated through M2/3 and β1/2 receptors, respectively.Sympathetic nerve activity mediated through β1/2 receptors is associated with an early delay in modulation of gastric motility by EA at ST36. 展开更多
关键词 Gastric MOTILITY ELECTROACUPUNCTURE Vagovagal reflex SYMPATHETIC nerve RATS
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The effects of androgen on penile reflex, erectile response to electrical stimulation and penile NOS activity in the rat 被引量:6
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作者 Seong Il Seo Soo Woong Kim Jae-Seung Paick 《Asian Journal of Andrology》 SCIE CAS CSCD 1999年第4期169-174,共6页
Aim: To investigate the effects of androgen on penile erection through the reflex arc and penile corpus cavernosum,and study the respective roles of testosterone (T) and dihydrotestosterone (DHT) in penile erection in... Aim: To investigate the effects of androgen on penile erection through the reflex arc and penile corpus cavernosum,and study the respective roles of testosterone (T) and dihydrotestosterone (DHT) in penile erection in rats. Methods:Male Sprague-Dawley rats were castrated and implanted with silastic brand silicone tube containing T or DHT, with orwithout daily injections of a 5α-reductase inhibitor, MK-434. The penile reflex, erectile response to electrical stimula-tion (ES) of the cavernous nerves and penile nitric-oxide synthase (NOS) activity were observed under varying andro-genic status. Results: Penile reflex erection in the rat was, on the whole, related to serum T levels though the numberof glans engorgements was not. The number of cups and flips was significantly decreased by castration, and restoredto the control level by T supplementation. Erectile response to ES and NOS activity in penile tissue was also related toserum T level. T administered together with a 5α-reductase inhibitor no longer restored the number of reflex erection,erectile responses to ES and NOS activity in the corpus cavernosum. Conclusion: Androgen influenced the penile re-flex arc, corpus cavernosum, and the perineal striated muscles. In reflex erection, erectile response to ES and penileNOS activity in the rat, T seems to be first converted to DHT, the more active androgen modality. (Asian J Androl1999 Dec; 1: 169-174) 展开更多
关键词 ANDROGENS penile erection reflex electric stimulation nitric-oxide synthase
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THE GENERALIZED REFLEXIVE SOLUTION FOR A CLASS OF MATRIX EQUATIONS (AX-B,XC=D) 被引量:7
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作者 李范良 胡锡炎 张磊 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期185-193,共9页
In this article, the generalized reflexive solution of matrix equations (AX = B, XC = D) is considered. With special properties of generalized reflexive matrices, the necessary and sufficient conditions for the solv... In this article, the generalized reflexive solution of matrix equations (AX = B, XC = D) is considered. With special properties of generalized reflexive matrices, the necessary and sufficient conditions for the solvability and the general expression of the solution are obtained. Moreover, the related optimal approximation problem to a given matrix over the solution set is solved. 展开更多
关键词 Matrix equations generalized reflexive matrix optimal approximation
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Artificial facial nerve reflex restores eyelid closure following orbicularis oculi muscle denervation 被引量:3
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作者 Yujuan Wang Keyong Li +3 位作者 Jingquan Liu Dongyue Xu Yuefeng Rui Chunsheng Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第22期1750-1755,共6页
To date, treatment of peripheral facial paralysis has focused on preservation of facial nerve integrity. However, with seriously damaged facial nerve cases, it is difficult to recover anatomical and functional integri... To date, treatment of peripheral facial paralysis has focused on preservation of facial nerve integrity. However, with seriously damaged facial nerve cases, it is difficult to recover anatomical and functional integrity using present therapies. Therefore, the present study utilized artificial facial nerve reflex to obtain orbicularis oculi muscle (OOM) electromyography signals on the uninjured side through the use of implanted recording electrodes. The implanted electrical chips analyzed facial muscle motion on the uninjured side and triggered an electrical stimulator to emit current pulses, which resulted in stimulation of injured OOM contraction and maintained bilateral symmetry and consistency. Following signal recognition, extraction, and computer analysis, electromyography signals in the uninjured OOM resulted in complete eyelid closure, which was consistent with the voltage threshold for eye closure. These findings suggested that artificial facial nerve reflex through the use of implanted microelectronics in unilateral peripheral facial paralysis could restore eyelid closure following orbicularis oculi muscle denervation. 展开更多
关键词 artificial facial nerve reflex facial paralysis/therapy electrical stimulation ELECTROMYOGRAPHY nerve regeneration
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H_1 and H_2 receptors in the locus ceruleus are involved in the intracere-broventricular histamine-induced carotid sinus baroreceptor reflex reset-ting in rats 被引量:2
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作者 Guo-Qing WANG Wan-Ping SUN Yong-Jin ZHU Rong ZOU Xi-Ping ZHOU 《Neuroscience Bulletin》 SCIE CAS CSCD 2006年第4期209-215,共7页
Objective To investigate the role of H1 and H2 receptors in the locus ceruleus (LC) in carotid sinus baroreceptor reflex (CSR) resetting induced by intracerebroventricular (i.c.v.) injection of histamine (HA).... Objective To investigate the role of H1 and H2 receptors in the locus ceruleus (LC) in carotid sinus baroreceptor reflex (CSR) resetting induced by intracerebroventricular (i.c.v.) injection of histamine (HA). Methods The left and right carotid sinus regions were isolated from the systemic circulation in 18 male Sprague-Dawley rats anesthetized with pentobarbital sodium. The intracarotid sinus pressure (ISP) was altered in a stepwise manner in vivo. ISP-mean arterial pressure (MAP) relationship curve and its characteristic parameters were constructed by fitting to the logistic function with five parameters. The changes in CSR performance induced by i.c.v. HA and the effects of pretreatment with H1 or H2 receptors selective antagonist, chlorpheniramine (CHL) or cimetidine (CIM) into the LC, on the responses of CSR to HA were examined. Results I.c.v. HA (100 ng in 5 μl) significantly shifted the ISP-MAP relationship curve upwards (P 〈 0.05) and obviously decreased the value of the reflex parameters such as MAP range and maximum gain (P 〈 0.05), but increased the threshold pressure, saturation pressure and ISP at maximum gain (P 〈 0.05). The pretreatment with CHL (0.5 μg in 1 μl) or CIM (1.5 μg in 1 μl) into the LC could obviously attenuate the changes mentioned above in CSR performance induced by HA, but the alleviative effect of CIM was less remarkable than that of CHL (P 〈 0.05). Respective microinjection of CHL or CIM alone into the LC with the corresponding dose and volume did not change CSR performance significantly (P 〉 0.05). Conclusion Intracerebroventricular administration of HA results in a rapid resetting of CSR and a decrease in reflex sensitivity, and the responses of CSR to HA may be mediated, at least in part, by H1 and H2 receptors activities in the LC, especially by H1 receptors. Moreover, the effects of the central HA on CSR might be related to a histaminergic descending pathway from the hypothalamus to LC. 展开更多
关键词 carotid sinus baroreceptor reflex HISTAMINE intracerebroventricular injection H1 receptor H2 receptor locus ceruleus mean arterial pressure
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Adaptive Walking of a Quadrupedal Robot Based on Layered Biological Reflexes 被引量:10
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作者 ZHANG Xiuli E Mingcheng +1 位作者 ZENG Xiangyu ZHENG Haojun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第4期654-664,共11页
A multiple-legged robot is traditionally controlled by using its dynamic model.But the dynamic-model-based approach fails to acquire satisfactory performances when the robot faces rough terrains and unknown environmen... A multiple-legged robot is traditionally controlled by using its dynamic model.But the dynamic-model-based approach fails to acquire satisfactory performances when the robot faces rough terrains and unknown environments.Referring animals' neural control mechanisms,a control model is built for a quadruped robot walking adaptively.The basic rhythmic motion of the robot is controlled by a well-designed rhythmic motion controller(RMC) comprising a central pattern generator(CPG) for hip joints and a rhythmic coupler(RC) for knee joints.CPG and RC have relationships of motion-mapping and rhythmic couple.Multiple sensory-motor models,abstracted from the neural reflexes of a cat,are employed.These reflex models are organized and thus interact with the CPG in three layers,to meet different requirements of complexity and response time to the tasks.On the basis of the RMC and layered biological reflexes,a quadruped robot is constructed,which can clear obstacles and walk uphill and downhill autonomously,and make a turn voluntarily in uncertain environments,interacting with the environment in a way similar to that of an animal.The paper provides a biologically inspired architecture,with which a robot can walk adaptively in uncertain environments in a simple and effective way,and achieve better performances. 展开更多
关键词 legged robot motion control central pattern generator(CPG) biological reflex
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Morphological Changes in Hippocampus and Prefrontal Cortex of Confined Sows with Prolonged Pupillary Light Reflex 被引量:2
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作者 Lv Fang-lu Li Xiang +3 位作者 Li Jian-hong Cui Shi-quan Liu Hong-gui Jun Bao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第3期39-46,共8页
Human depression patients often show abnormal pupillary reflex with morphological changes in hippo campus and prefrontal cortex. This study aimed to find the relationship between the prolonged pupillary light reflex ... Human depression patients often show abnormal pupillary reflex with morphological changes in hippo campus and prefrontal cortex. This study aimed to find the relationship between the prolonged pupillary light reflex (PLR) which had been shown by confined sows with chronic stress or depression and morphological changes in brain, in order to provide theoretical basis for that the confined environment should lead to sows' depression. A total of 637 sows of Durac, Landrace and Large White breeds with various parities were observed, and the pupil light reflex (PLR) was measured and the actual pupillary light reflex time (PLRT) were recorded. All the PLRTs were grouped based on the results of confidence interval: t〉10% as group A, 5% 〈t〈10% as group B, 1%〈t〈5% as group C and t〈l% as group D. Three individuals were randomly selected from each group (12 sows in total) and the white tissues of hippocampus and the prefrontal cortex were prepared for HS staining slices (three slices/per tissue) for observation on tissue structure and pathological changes with high magnification (400X) of electronic microscope. The results showed that in group A (t〉10%) pathological change was found in hippocampus, however, as PLRT increased from group B to group D, pathological changes in hippocampus tissues tended to be deteriorated with the increase of inflammatory cells and nuclear pyknosis phenomena. The same as those shown in hippocampus as the increasing of PLRT from groups A to D, more inflammatory cells appeared in prefrontal cortex for groups B and D. The results suggested that the tissue lesions of hippocampus and prefrontal cortex of the confined sows with prolonged PLRT might be the results of chronic stress or depression. 展开更多
关键词 SOW pupillary light reflex time brain tissue morphology DEPRESSION
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“反思社会学”,还是“反身社会学”--Reflexive Sociology汉译探析 被引量:1
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作者 李睿 《中国科技术语》 2017年第1期50-52,共3页
对布迪厄思想关键词reflexive sociology,现至少有"反思社会学""反思性社会学""反观社会学""反身社会学""反身性社会学"等五种译法。鉴于"反思社会学"之"反思"... 对布迪厄思想关键词reflexive sociology,现至少有"反思社会学""反思性社会学""反观社会学""反身社会学""反身性社会学"等五种译法。鉴于"反思社会学"之"反思"混淆了reflexive和reflective,前者尚可译为"反身",后者除了"反思"再无词可译。使用"反思社会学"无异于让reflexive抢了reflective的地盘,而reflective在布迪厄著作中同样常见。reflexive本义即为"反身",且布迪厄赋予实践突出的意义,而实践仰仗行动者的身体。在汉语中,"身"有"我自己""你自己""他自己"之意,如"反求诸身";又有实践的意蕴,如"身体力行"。故建议使用"反身社会学"翻译reflexive sociology。 展开更多
关键词 reflexIVE SOCIOLOGY 布迪厄 实践 行动者
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