Structure and Physiology of a Chordotonal Organ in the Locust Leg

1968 ◽  
Vol 48 (2) ◽  
pp. 305-323 ◽  
Author(s):  
P. N. R. USHERWOOD ◽  
H. I. RUNION ◽  
J. I. CAMPBELL
Keyword(s):  
Significant Role ◽  
Chordotonal Organ ◽  
Phasic Response ◽  
Physiological Properties ◽  
Walking Activity

1. The structural and physiological properties of a chordotonal organ found in the metathoracic femoral segments of the locust and grasshopper are described. 2. Recordings from the afferent fibres of this mechanoreceptor reveal two patterns of activity: a static or tonic discharge and a dynamic or phasic, rapidly adapting discharge. The frequency of the tonic discharge varies with the femur-tibia angle, while the phasic discharge occurs in response to angular movements of the tibia of > 3'. The frequency of the phasic response is related to the velocity of tibial displacement. The responses recorded during flexion of the tibia are different from those recorded during extension. 3. Removal of either of the metathoracic chordotonal organs produces significant changes in walking and postural behaviour. 4. Leg reflexes involving the femoral chordotonal organ and femoral muscles appear to play a very significant role during postural and walking activity.

Tarsal Receptors and Leg Reflexes in the Locust and GRASSHOPPER

1968 ◽  
Vol 49 (2) ◽  
pp. 421-436
Author(s):  
H. I. RUNION ◽  
P. N. R. USHERWOOD
Keyword(s):  
Significant Role ◽  
Discharge Frequency ◽  
Sensilla Trichodea ◽  
Physiological Properties ◽  
Walking Activity ◽  
Hair Sensilla

1. The physiological properties of hair sensilla found on the metathoracic tarsal segments of the locust and grasshopper are described. 2. The sensilla trichodea are phasically responsive mechanoreceptors. The discharge frequency of these receptors is proportional to the velocity of displacement of the sensory appendage. Phase-related responses are obtained with sinusoidal inputs less than ioo Hz. With higher input frequencies the receptors respond asynchronously. 3. The tarsal sensilla signal contact of the tarsal segments with the substratum and changes in the load on the metathoracic leg. 4. Reflexes involving these tarsal receptors and the ‘fast’ and ‘slow’ excitatory and inhibitory neurones which innervate the metathoracic extensor tibiae muscle have been demonstrated and appear to play a significant role during postural and walking activity.

A new muscle receptor organ in the antenna of the rock lobster Palinurus vulgaris : mechanical, muscular and proprioceptive organization of the two proximal joints J0 and J1

1983 ◽  
Vol 218 (1210) ◽  
pp. 95-110 ◽  
Keyword(s):  
Anterior Part ◽  
Proximal Part ◽  
The Other ◽  
Chordotonal Organ ◽  
Excitatory Postsynaptic Potentials ◽  
Rock Lobster ◽  
Postsynaptic Potentials ◽  
Muscle Receptor ◽  
Physiological Properties ◽  
Receptor Organ

(i) Following previous work on the morphological and physiological properties of the two distal joints (J2, J3) of the atenna of the rock lobster Palinurus vulgaris , the mechanical, muscular and proprioceptive organization of the two proximal joints between the antennal segments S1 and S2 (J1) and between S1 and the cephalothorax (J0) have now been studied. (ii) Articulated by two classical condyles, J1 moves in a mediolateral plane. One external rotator muscle (ER) and three internal rotator muscles (IR1, IR2, IR3) subserve its movements. J0 is articulated by two different systems: a classical ventrolateral condyle and a complex sliding system constituted by special cuticular structures on the dorsomedial side of the S1 segment and on the rostrum between the two antennae. J0 moves in the dorsoventral plane by means of a levator muscle (Lm) and a depressor muscle (Dm). A third muscle, the lateral tractor muscle (LTm), associated with J0 and lying obliquely across S1, may modulate the level of friction between the S1 segment and the rostrum. (iii) Proprioception in J1 is achieved by a muscle receptor organ AMCO-J1 (antennal myochordotonal organ for the J1 joint) associating a small accessory muscle (S1.am) located in the proximal part of the S1 segment and a chordotonal organ inserted proximally on the S1.am muscle and distally on the S2 segment. J0 proprioception is ensured by a simple chordotonal organ (CO-J0) located in the anterior part of the cephalothorax. (iv) The S1.am muscle is innervated by three motoneurons characterized by their very small diameters and inducing respectively tonic excitatory postsynaptic potentials, phasic excitatory postsynaptic potentials and inhibitory postsynaptic potentials. Anatomical and physiological observations suggest functional correlation between S1.am and IR1 motor innervation. (v) Mechanical and muscular organization of J0 and J1 are compared with that of the other joints of the antenna. The properties of the AMCO-J1 proprioceptor are discussed in relation to the other muscle receptor organs described in crustaceans.

scholarly journals PAIR INFLUENCE OF WIND SPEED AND MEAN RADIANT TEMPERATURE ON OUTDOOR THERMAL COMFORT OF HUMID TROPICAL ENVIRONMENT

2017 ◽  
Vol 10 (2) ◽  
pp. 177-185 ◽  
Author(s):  
Sangkertadi Sangkertadi ◽  
Reny Syafriny
Keyword(s):  
Wind Speed ◽  
Thermal Comfort ◽  
Significant Role ◽  
Tropical Environment ◽  
Outdoor Thermal Comfort ◽  
Regression Equations ◽  
Mean Radiant Temperature ◽  
Walking Activity ◽  
Globe Temperature ◽  
Radiant Temperature

The purposes of this article is to explore knowledge of outdoor thermal comfort in humid tropical environment for urban activities especially for people in walking activity, and those who stationary/seated with moderate action. It will be characterized the pair influence of wind speed and radiant temperature on the outdoor thermal comfort. Many of researchers stated that those two microclimate variables give significant role on outdoor thermal comfort in tropical humid area. Outdoor Tropical Comfort (OTC) model was used for simulation in this study. The model output is comfort scale that refers on ASHRAE definition. The model consists of two regression equations with variables of air temperature, globe temperature, wind speed, humidity and body posture, for two types of activity: walking and seated. From the results it can be stated that there is significant role of wind speed to reduce mean radiant temperature and globe temperature, when the velocity is elevated from 0.5 m/s to 2 m/s. However, the wind has not play significant role when the speed is changed from 2 m/s to 3.5 m/s. The results of the study may inspire us to implement effectiveness of electrical-fan equipment for outdoor space in order to get optimum wind speed, coupled with optimum design of shading devices to minimize radiant temperature for thermal comfort.

scholarly journals PAIR INFLUENCE OF WIND SPEED AND MEAN RADIANT TEMPERATURE ON OUTDOOR THERMAL COMFORT OF HUMID TROPICAL ENVIRONMENT

2017 ◽  
Vol 10 (2) ◽  
pp. 177-185
Author(s):  
Sangkertadi Sangkertadi ◽  
Reny Syafriny
Keyword(s):  
Wind Speed ◽  
Thermal Comfort ◽  
Significant Role ◽  
Tropical Environment ◽  
Outdoor Thermal Comfort ◽  
Regression Equations ◽  
Mean Radiant Temperature ◽  
Walking Activity ◽  
Globe Temperature ◽  
Radiant Temperature

The purposes of this article is to explore knowledge of outdoor thermal comfort in humid tropical environment for urban activities especially for people in walking activity, and those who stationary/seated with moderate action. It will be characterized the pair influence of wind speed and radiant temperature on the outdoor thermal comfort. Many of researchers stated that those two microclimate variables give significant role on outdoor thermal comfort in tropical humid area. Outdoor Tropical Comfort (OTC) model was used for simulation in this study. The model output is comfort scale that refers on ASHRAE definition. The model consists of two regression equations with variables of air temperature, globe temperature, wind speed, humidity and body posture, for two types of activity: walking and seated. From the results it can be stated that there is significant role of wind speed to reduce mean radiant temperature and globe temperature, when the velocity is elevated from 0.5 m/s to 2 m/s. However, the wind has not play significant role when the speed is changed from 2 m/s to 3.5 m/s. The results of the study may inspire us to implement effectiveness of electrical-fan equipment for outdoor space in order to get optimum wind speed, coupled with optimum design of shading devices to minimize radiant temperature for thermal comfort.

Economic Views of L. Trotsky

2004 ◽  
pp. 142-157
Author(s):  
M. Voeikov ◽  
S. Dzarasov
Keyword(s):  
Civil War ◽  
20Th Century ◽  
Significant Role ◽  
Historical Perspective ◽  
Russian Revolution ◽  
Russian History ◽  
History Of

The paper written in the light of 125th birth anniversary of L. Trotsky analyzes the life and ideas of one of the most prominent figures in the Russian history of the 20th century. He was one of the leaders of the Russian revolution in its Bolshevik period, worked with V. Lenin and played a significant role in the Civil War. Rejected by the party bureaucracy L. Trotsky led uncompromising struggle against Stalinism, defending his own understanding of the revolutionary ideals. The authors try to explain these events in historical perspective, avoiding biases of both Stalinism and anticommunism.

The Role of Muslim Women in Civil Society In Promoting Values and Principles for Building Peace: Action Guide from The Qur’ān

Sains Insani ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 30-36
Author(s):  
Che Amnah Bahari ◽  
Fatimah Abdullah
Keyword(s):  
Civil Society ◽  
Lifelong Learning ◽  
Significant Role ◽  
Textual Analysis ◽  
Muslim Women ◽  
Peace Building ◽  
Analysis Method ◽  
Pluralistic Society ◽  
Women And Children

The whole world, the Muslim in particular has witnessed conflicts in different areas, which have hindered the developmental efforts of the nations concerned. It should be learned that most victims of these conflicts are women and children. This article attempts to elaborate the role of Muslims Women as a crucial segment in civil society in initiating peace building through nurturing process. It maintains that the adoption of the principles and values derived from the Qur’ān and Sunnah of the Prophet is necessary as a process of lifelong learning.  Those identified values constituted the framework of this article and it adopts the textual analysis method.   This article concludes that through the implementation of those values and frameworks for peace building, women as one of the important segments of civil society are able to play significant role towards initiating peace building and promoting peaceful co-existence in pluralistic society. Abstrak: Dunia Islam khususnya telah menyaksikan konflik di pelbagai daerah yang berbeza. Konflik ini telah menghalang usaha kearah pembangunan Kawasan yang berkenaan. Kebanyakan mangsa konflik ini adalah wanita dan kanak-kanak. Artikel ini cuba untuk menghuraikan peranan wanita Islam sebagai segmen penting dalam masyarakat madani dalam membangun proses kedamaian dengan mendidik dan memupuk prinsip dan nilai murni janaan al-Qur’an. Penggunaan prinsip dan nilai yang dikutip dari ayat-ayat Qur'an dan hadis Rasulullah adalah keperluan yang mendesak sebagai wadah bagi proses pembelajaran sepanjang hayat. Nilai-nilai yang dikenal pasti merupakan rangka kerja artikel ini, dan metod yang dirujuk adalah analisis teks. Artikel ini menyimpulkan bahawa melalui pelaksanaan nilai-nilai dan kerangka kerja Islam bagi proses kedamaian, wanita Islam dalam masyarakat madani mampu memainkan peranan penting dalam memulakan pembinaan keamanan dan menggalakkan kehidupan yang harmonis, sejahtera dan saling bantu membantu dalam masyarakat majmuk.

Ethnic niching in a segmented labour market: Evidence from Spain

2012 ◽  
Vol 9 (3) ◽  
pp. 249-262 ◽  
Author(s):  
Mikolaj Stanek ◽  
Alberto Veira
Keyword(s):  
Social Capital ◽  
Labour Market ◽  
Significant Role ◽  
Immigrant Workers ◽  
Structural Factors ◽  
Immigrant Communities ◽  
Logit Models ◽  
Human And Social Capital

Using the Spanish National Immigrant Survey (NIS-2007) we identify the ethnic niches where workers from five main immigrant communities concentrate. We then implement logit models in order to assess how structural factors and human and social capital variables affect the odds of working in these niches. We observe that the strong segmentation of the Spanish labour market strongly favours the concentration of immigrants in certain occupational niches. Nevertheless, variables related to human and social capital still play a significant role in the placement of immigrant workers in different niches, all of which are not equally attractive. 

The impact of cultural factors on attachment dynamics: a view from Irish society

2019 ◽  
Vol 13 (2) ◽  
pp. 207-223
Author(s):  
Michael O’Toole
Keyword(s):  
Significant Role ◽  
Emotional Development ◽  
Cultural Factors ◽  
Seamus Heaney ◽  
Irish Society ◽  
Irish Context ◽  
Key Points ◽  
The Many ◽  
The Impact ◽  
The Relationship

In this article I examine aspects of the relationship between mothers and sons from an attachment perspective in an Irish context. Through the works of Irish writers such as Seamus Heaney, John McGahern, and Colm Tóibín, I focus on particular aspects of this relationship, which fails to support the developmental processes of separation and individuation in the many men who come to me for psychotherapy. I illustrate key points concerning this attachment dynamic through the use of clinical examples of my work with two men from my practice. While acknowledging that many other cultural factors play a significant role in the emotional development of children, integrating the work of our poets, novelists, and scholars with an attachment perspective

POLICY CHANGE – THE ROLE OF IDEAS AND POLICY ENTREPRENEURS

2018 ◽  
pp. 63-72
Author(s):  
Arwanto Arwanto ◽  
Wike Anggraini
Keyword(s):  
Policy Change ◽  
Significant Role ◽  
Policy Process ◽  
Policy Entrepreneurs ◽  
Multiple Streams ◽  
Policy Makers ◽  
Problem Framing ◽  
Exogenous Factors ◽  
The Relationship

ABSTRACT Understanding policy process involves many distinctive approaches. The most common are institutional, groups or networks, exogenous factors, rational actors, and idea-based approach. This paper discussed the idea-based approach to explain policy process, in this case policy change. It aims to analyse how ideas could assist people to understand policy change. What role do they play and why are they considered as fundamental element? It considers that ideas are belong to every policy actor, whether it is individual or institution. In order to answer these questions, this paper adopts Kingdon’s multi streams approach to analyse academic literatures. Through this approach, the relationship between ideas and policy change can be seen clearer. Ideas only can affect in policy change if it is agreed and accepted by policy makers. Therefore the receptivity of ideas plays significant role and it emerges policy entrepreneurs. They promote ideas (through problem framing, timing, and narrative construction) and manipulate in order to ensure the receptivity of ideas. Although policy entrepreneurs play significant role, political aspects remains the most important element in the policy process. Keywords: policy change, ideas, idea-based approach, Kingdon’s multiple streams, policy entrepreneurs.

A Good Sentencing Precedent is Hard to Find

2020 ◽  
Vol 32 (3) ◽  
pp. 138-144
Author(s):  
Brian A. Jacobs
Keyword(s):  
United States ◽  
Significant Role ◽  
College Admissions ◽  
The Body ◽  
Federal Law ◽  
Criminal Cases ◽  
Federal Sentencing

In federal criminal cases, federal law requires that judges consider the sentences other courts have imposed in factually similar matters. Courts and parties, however, face significant challenges in finding applicable sentencing precedents because judges do not typically issue written sentencing opinions, and transcripts of sentencings are not readily available in advanced searchable databases. At the same time, particularly since the Supreme Court’s 2005 decision in United States v. Booker, sentencing precedent has come to play a significant role in federal sentencing proceedings. By way of example, this article discusses recent cases involving defendants with gambling addictions, and recent cases involving college admissions or testing fraud. The article explores the ways the parties in those cases have used sentencing precedent in their advocacy, as well as the ways the courts involved have used sentencing precedent to justify their decisions. Given the important role of sentencing precedent in federal criminal cases, the article finally looks at ways in which the body of sentencing law could be made more readily available to parties and courts alike.

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