scholarly journals GABAergic inhibition of leg motoneurons is required for normal walking behavior in freely moving Drosophila

2017 ◽  
Author(s):  
Swetha B.M. Gowda ◽  
Pushkar D. Paranjpe ◽  
O. Venkateswara Reddy ◽  
Sudhir Palliyil ◽  
Heinrich Reichert ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
High Speed ◽  
Walking Speed ◽  
Step Length ◽  
Inhibitory Input ◽  
Rhythmic Pattern ◽  
Normal Walking ◽  
Inhibitory Neurotransmitter ◽  
Leg Movement

ABSTRACTWalking is a complex rhythmic locomotor behaviour generated by sequential and periodical contraction of muscles essential for coordinated control of movements of legs and leg joints. Studies of walking in vertebrates and invertebrates have revealed that premotor neural circuitry generates a basic rhythmic pattern that is sculpted by sensory feedback and ultimately controls the amplitude and phase of the motor output to leg muscles. However, the identity and functional roles of the premotor interneurons that directly control leg motoneuron activity are poorly understood. Here we take advantage of the powerful genetic methodology available in Drosophila to investigate the role of premotor inhibition in walking by genetically suppressing inhibitory input to leg motoneurons. For this, we have developed a novel algorithm for automated analysis of leg motion to characterize the walking parameters of wildtype flies from high speed video recordings. Further, we use genetic reagents for targeted RNAi knockdown of inhibitory neurotransmitter receptors in leg motoneurons together with quantitative analysis of resulting changes in leg movement parameters in freely walking Drosophila. Our findings indicate that targeted down regulation of GABAA receptor Rdl in leg motoneurons results in a dramatic reduction of walking speed and step-length without the loss of general leg coordination during locomotion. Genetically restricting the knockdown to the adult stage and subsets of motoneurons yields qualitatively identical results. Taken together, these findings identify GABAergic premotor inhibition of motoneurons as an important determinant of correctly coordinated leg movements and speed of walking in freely behaving Drosophila.SIGNIFICANCE STATEMENTInhibition is an important feature of neuronal circuit and in walking it aids in controlling coordinated movement of legs, leg segments and leg joints. Recent studies in Drosophila reports the role of premotor inhibitory interneurons in regulation of larval locomotion. However, in adult walking the identity and functional role of premotor interneurons is less understood. Here, we use genetic methods for targeted knockdown of inhibitory neurotransmitter receptor in leg motoneurons that results in slower walking speed and defects in walking parameters combined with novel method we have developed for quantitative analysis of the fly leg movement and the observed changes in walking parameters. Our results indicate that GABAergic pre-motor inhibition to leg motoneurons is required to control the normal walking behaviour in adult Drosophila.

scholarly journals GABAergic inhibition of leg motoneurons is required for normal walking behavior in freely moving Drosophila

2018 ◽  
Vol 115 (9) ◽  
pp. E2115-E2124 ◽  
Author(s):  
Swetha B. M. Gowda ◽  
Pushkar D. Paranjpe ◽  
O. Venkateswara Reddy ◽  
Devasena Thiagarajan ◽  
Sudhir Palliyil ◽  
...  
Keyword(s):  
High Speed ◽  
Automated Analysis ◽  
Step Length ◽  
Inhibitory Input ◽  
Rhythmic Pattern ◽  
Walking Behavior ◽  
Inhibitory Neurotransmitter ◽  
Functional Roles ◽  
Leg Motion ◽  
Movement Parameters

Walking is a complex rhythmic locomotor behavior generated by sequential and periodical contraction of muscles essential for coordinated control of movements of legs and leg joints. Studies of walking in vertebrates and invertebrates have revealed that premotor neural circuitry generates a basic rhythmic pattern that is sculpted by sensory feedback and ultimately controls the amplitude and phase of the motor output to leg muscles. However, the identity and functional roles of the premotor interneurons that directly control leg motoneuron activity are poorly understood. Here we take advantage of the powerful genetic methodology available in Drosophila to investigate the role of premotor inhibition in walking by genetically suppressing inhibitory input to leg motoneurons. For this, we have developed an algorithm for automated analysis of leg motion to characterize the walking parameters of wild-type flies from high-speed video recordings. Further, we use genetic reagents for targeted RNAi knockdown of inhibitory neurotransmitter receptors in leg motoneurons together with quantitative analysis of resulting changes in leg movement parameters in freely walking Drosophila. Our findings indicate that targeted down-regulation of the GABAA receptor Rdl (Resistance to Dieldrin) in leg motoneurons results in a dramatic reduction of walking speed and step length without the loss of general leg coordination during locomotion. Genetically restricting the knockdown to the adult stage and subsets of motoneurons yields qualitatively identical results. Taken together, these findings identify GABAergic premotor inhibition of motoneurons as an important determinant of correctly coordinated leg movements and speed of walking in freely behaving Drosophila.

A Statistical Study of Process Variables to Optimize a High Speed Curtain Coater: Part I

TAPPI Journal ◽  
2009 ◽  
Vol 8 (1) ◽  
pp. 20-26 ◽  
Author(s):  
PEEYUSH TRIPATHI ◽  
MARGARET JOYCE ◽  
PAUL D. FLEMING ◽  
MASAHIRO SUGIHARA
Keyword(s):  
Boundary Layer ◽  
Experimental Design ◽  
High Speed ◽  
Statistical Study ◽  
Process Variables ◽  
High Speeds ◽  
The Stability ◽  
Air Removal ◽  
Removal System

Using an experimental design approach, researchers altered process parameters and material prop-erties to stabilize the curtain of a pilot curtain coater at high speeds. Part I of this paper identifies the four significant variables that influence curtain stability. The boundary layer air removal system was critical to the stability of the curtain and base sheet roughness was found to be very important. A shear thinning coating rheology and higher curtain heights improved the curtain stability at high speeds. The sizing of the base sheet affected coverage and cur-tain stability because of its effect on base sheet wettability. The role of surfactant was inconclusive. Part II of this paper will report on further optimization of curtain stability with these four variables using a D-optimal partial-facto-rial design.

Peranan Whistleblowing Dalam Meningkatkan Integriti Anggota Polis Diraja Malaysia (Pdrm): Kajian Ke Atas Kontinjen Perak

Sains Insani ◽  
2018 ◽  
Vol 2 (1) ◽  
pp. 17-27
Author(s):  
Megat Ayop Megat Arifin ◽  
Abd. Halim Ahmad
Keyword(s):  
Quantitative Analysis ◽  
Demographic Factors ◽  
Positive Perception ◽  
External Threats ◽  
Positive Practices ◽  
The Impact ◽  
The Relationship

Whitsleblowing is one of the positive practices in organizations that are able to raise the level of integrity among the members of an organization. However, the roles of whistleblowing also inevitably invites a response, especially among members of the organization itself. This is because such practices are viewed as one factor that may be detrimental to the organization in addition to revealing the reporter (whistleblower) to some external threats and intimidation of discrimination within the organization. This paper is an attempt to examine the relationship between perceptions of members of the Royal Malaysian Police (RMP) Contingent of Perak through the role of whistleblowing practices to increase the perception of the integrity of the members. Next, identify the purpose of the whistleblowing and its effect on the integrity of the members of the organization. This study used a descriptive quantitative analysis to identify patterns of relationship that exists between the perception of whistleblowing practices with perceptions of increased integrity based on three basic variables of demographic factors, response to whistleblowing and the impact of making the report. The results showed that members of the Perak’s police have a positive perception of whistleblowing practices which are seen to be done in improving the integrity of the members.Keywords: whistleblowing, perception, RMP members, culture, integrity, organization, influence. ABSTRAK: Whitsleblowing merupakan salah satu amalan positif dalam organisasi yang mampu untuk meningkatkan tahap integriti ahli-ahli dalam sesebuah organisasi. Namun begitu, amalan whistleblowing juga turut tidak dapat mengelak daripada mengundang pelbagai respon khususnya dalam kalangan ahli organisasi itu sendiri. Amalan sebegini turut dilihat sebagai salah satu faktor yang boleh memudaratkan organisasi di samping mendedahkan pelapor (whistleblower) kepada beberapa bentuk ancaman ugutan dari luar dan diskriminasi dalam organisasi. Kertas ini merupakan satu upaya untuk melihat perkaitan antara persepsi anggota Polis Diraja Malaysia (PDRM) Kontinjen Perak melalui peranan amalan whistleblowing terhadap persepsi peningkatan integriti anggota. Seterusnya, mengenalpasti maksud whistleblowing dan pengaruhnya terhadap tahap integriti anggota dalam organisasi. Kajian ini menggunakan analisis kuantitatif berbentuk deskriptif bagi mengenalpasti corak hubungan yang wujud antara persepsi terhadap amalan whistleblowing dengan persepsi terhadap peningkatan integriti berdasarkan tiga pembolehubah asas iaitu faktor demografi, tanggapan terhadap whistleblowing dan kesan daripada tindakan membuat laporan. Dapatan kajian menunjukkan bahawa anggota PDRM Perak mempunyai persepsi yang positif terhadap whistleblowing yang mana ianya dilihat perlu dilaksanakan dalam meningkatkan integriti anggota.Kata kunci: whistleblowing, persepsi, amalan, anggota PDRM, budaya, integriti, organisasi, pengaruh.  

LANDSLIDE RISK MANAGEMENT IN THE COASTAL ZONE OF THE KUIBYSHEV RESERVOIR DUE THE DESIGN OF HIGH-SPEED LINE "MOSCOW-KAZAN"

2017 ◽  
Author(s):  
Nikolai Petrov ◽  
Nikolai Petrov ◽  
Inna Nikonorova ◽  
Inna Nikonorova ◽  
Vladimir Mashin ◽  
...  
Keyword(s):  
High Speed ◽  
Computational Models ◽  
Stable State ◽  
Landslide Risk ◽  
Kuibyshev Reservoir ◽  
Stepped Surface ◽  
The Stability ◽  
Landslide Slope ◽  
The Village

High-speed railway "Moscow-Kazan" by the draft crosses the Volga (Kuibyshev reservoir) in Chuvashia region 500 m below the village of New Kushnikovo. The crossing plot is a right-bank landslide slope with a stepped surface. Its height is 80 m; the slope steepness -15-16o. The authors should assess the risk of landslides and recommend anti-landslide measures to ensure the safety of the future bridge. For this landslide factors have been analyzed, slope stability assessment has been performed and recommendations have been suggested. The role of the following factors have been analyzed: 1) hydrologic - erosion and abrasion reservoir and runoff role; 2) lithologyc (the presence of Urzhum and Northern Dvina horizons of plastically deformable rocks, displacement areas); 3) hydrogeological (the role of perched, ground and interstratal water); 4) geomorphological (presence of the elemental composition of sliding systems and their structure in the relief); 5) exogeodynamic (cycles and stages of landslide systems development, mechanisms and relationship between landslide tiers of different generations and blocks contained in tiers). As a result 6-7 computational models at each of the three engineering-geological sections were made. The stability was evaluated by the method “of the leaning slope”. It is proved that the slope is in a very stable state and requires the following measures: 1) unloading (truncation) of active heads blocks of landslide tiers) and the edge of the plateau, 2) regulation of the surface and groundwater flow, 3) concrete dam, if necessary.

scholarly journals Effectiveness of an ankle–foot orthosis on walking in patients with stroke: a systematic review and meta-analysis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yoo Jin Choo ◽  
Min Cheol Chang
Keyword(s):  
Stride Length ◽  
Walking Speed ◽  
Sagittal Plane ◽  
Meta Analysis ◽  
Step Length ◽  
Stride Time ◽  
Plane Angle ◽  
Ankle Foot Orthosis ◽  
Biomechanical Parameters ◽  
Foot Orthosis

AbstractWe conducted a meta-analysis to investigate the effectiveness of ankle–foot orthosis (AFO) use in improving gait biomechanical parameters such as walking speed, mobility, and kinematics in patients with stroke with gait disturbance. We searched the MEDLINE (Medical Literature Analysis and Retrieval System Online), CINAHL (Cumulative Index to Nursing and Allied Health Literature), Cochrane, Embase, and Scopus databases and retrieved studies published until June 2021. Experimental and prospective studies were included that evaluated biomechanics or kinematic parameters with or without AFO in patients with stroke. We analyzed gait biomechanical parameters, including walking speed, mobility, balance, and kinematic variables, in studies involving patients with and without AFO use. The criteria of the Cochrane Handbook for Systematic Reviews of Interventions were used to evaluate the methodological quality of the studies, and the level of evidence was evaluated using the Research Pyramid model. Funnel plot analysis and Egger’s test were performed to confirm publication bias. A total of 19 studies including 434 participants that reported on the immediate or short-term effectiveness of AFO use were included in the analysis. Significant improvements in walking speed (standardized mean difference [SMD], 0.50; 95% CI 0.34–0.66; P < 0.00001; I2, 0%), cadence (SMD, 0.42; 95% CI 0.22–0.62; P < 0.0001; I2, 0%), step length (SMD, 0.41; 95% CI 0.18–0.63; P = 0.0003; I2, 2%), stride length (SMD, 0.43; 95% CI 0.15–0.71; P = 0.003; I2, 7%), Timed up-and-go test (SMD, − 0.30; 95% CI − 0.54 to − 0.07; P = 0.01; I2, 0%), functional ambulation category (FAC) score (SMD, 1.61; 95% CI 1.19–2.02; P < 0.00001; I2, 0%), ankle sagittal plane angle at initial contact (SMD, 0.66; 95% CI 0.34–0.98; P < 0.0001; I2, 0%), and knee sagittal plane angle at toe-off (SMD, 0.39; 95% CI 0.04–0.73; P = 0.03; I2, 46%) were observed when the patients wore AFOs. Stride time, body sway, and hip sagittal plane angle at toe-off were not significantly improved (p = 0.74, p = 0.07, p = 0.07, respectively). Among these results, the FAC score showed the most significant improvement, and stride time showed the lowest improvement. AFO improves walking speed, cadence, step length, and stride length, particularly in patients with stroke. AFO is considered beneficial in enhancing gait stability and ambulatory ability.

Role of secondary phase particles in fatigue behavior of high-speed railway gearbox material

2020 ◽  
Vol 131 ◽  
pp. 105336 ◽  
Author(s):  
Yinan Jiao ◽  
Yifan Zhang ◽  
Shiqing Ma ◽  
Deli Sang ◽  
Yang Zhang ◽  
...  
Keyword(s):  
High Speed ◽  
Fatigue Behavior ◽  
Secondary Phase ◽  
High Speed Railway

scholarly journals Towards a Glass New World: The Role of Ion-Exchange in Modern Technology

2021 ◽  
Vol 11 (10) ◽  
pp. 4610
Author(s):  
Simone Berneschi ◽  
Giancarlo C. Righini ◽  
Stefano Pelli
Keyword(s):  
Ion Exchange ◽  
Communication Networks ◽  
High Speed ◽  
High Performance ◽  
Low Cost ◽  
Modern Technology ◽  
Historical Background ◽  
Wide Range ◽  
Happy Marriage

Glasses, in their different forms and compositions, have special properties that are not found in other materials. The combination of transparency and hardness at room temperature, combined with a suitable mechanical strength and excellent chemical durability, makes this material indispensable for many applications in different technological fields (as, for instance, the optical fibres which constitute the physical carrier for high-speed communication networks as well as the transducer for a wide range of high-performance sensors). For its part, ion-exchange from molten salts is a well-established, low-cost technology capable of modifying the chemical-physical properties of glass. The synergy between ion-exchange and glass has always been a happy marriage, from its ancient historical background for the realisation of wonderful artefacts, to the discovery of novel and fascinating solutions for modern technology (e.g., integrated optics). Getting inspiration from some hot topics related to the application context of this technique, the goal of this critical review is to show how ion-exchange in glass, far from being an obsolete process, can still have an important impact in everyday life, both at a merely commercial level as well as at that of frontier research.

The Role of Porous Media in Homogenization of High Pressure Diesel Fuel Spray Combustion

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Navid Shahangian ◽  
Damon Honnery ◽  
Jamil Ghojel
Keyword(s):  
High Pressure ◽  
Porous Media ◽  
High Speed ◽  
Fuel Spray ◽  
Compression Ignition Engines ◽  
System Pressure ◽  
Novel Approach ◽  
Air Mixing ◽  
The Media

Interest is growing in the benefits of homogeneous charge compression ignition engines. In this paper, we investigate a novel approach to the development of a homogenous charge-like environment through the use of porous media. The primary purpose of the media is to enhance the spread as well as the evaporation process of the high pressure fuel spray to achieve charge homogenization. In this paper, we show through high speed visualizations of both cold and hot spray events, how porous media interactions can give rise to greater fuel air mixing and what role system pressure and temperature plays in further enhancing this process.

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