The role of visual reafferents during a pointing movement: comparative study between open-loop and closed-loop performances in monkeys before and after unilateral electrolytic lesion of the sustantia nigra

1987 ◽  
Vol 65 (2) ◽  
Author(s):  
F. Viallet ◽  
E. Trouche ◽  
D. Beaubaton ◽  
E. Legallet
2015 ◽  
Vol 744-746 ◽  
pp. 17-24
Author(s):  
Eugen Avrigean

On the basis of a comparative study, this paper aims to determine the maximum loads that can occur in operating conditions on the cardanic transmission assembly of motor vehicles in the open or closed loop configurations. The research is conducted under static conditions using finite elements and shows the components with their maximum values obtained in normal operating conditions.


1992 ◽  
Vol 68 (3) ◽  
pp. 933-944 ◽  
Author(s):  
F. A. Ottenhoff ◽  
A. van der Bilt ◽  
H. W. van der Glas ◽  
F. Bosman

1. During chewing, a small part of the observed muscle activity is needed for the basic open-close movements of the mandible, and much additional muscle activity (AMA) is needed to overcome the resistance of the food. In chewing cycles in which a counteracting force is expected, the AMA is mainly generated by peripheral induction with a latency of approximately 23 ms. It was investigated whether an open-loop or closed-loop mechanism is involved in the control of the AMA in these cycles. 2. Subjects made rhythmic open-close movements at their natural chewing frequency controlled by a metronome. Food resistance was simulated by an external force, acting on the jaw in a downward direction during part of the closing movement. Sequences of cycles with a force were unexpectedly alternated with sequences of cycles with a different force. The force changed from 19 to 0 N and vice versa, and from 25 to 6 N and vice versa. Jaw movement and surface electromyogram of the masseter, temporalis, and suprahyoid muscles on both sides were recorded during cycles before and after the transition from one force condition to another. 3. The movement trajectory and AMA of the second and following cycles with a new force appeared to be similar. Thus adaptation to the changed circumstances occurred within two open-close cycles. 4. In the first cycle with 0 or 6 N in the 19----0 N and 25----6 N experiments respectively, a large part of the AMA had disappeared. The AMA in this cycle started to differ from the AMA in the previous cycle approximately 23 ms after the moment the force in this cycle started to differ from the previous cycle. 5. In the first cycle with 19 or 25 N in the reverse experiments, the AMA increased 120–136 ms after the moment the force in this cycle started to differ from the previous cycle. 6. During the closing phase of each open-close cycle, no muscle activity of the suprahyoid muscles was observed; thus co-contraction with the elevator muscles did not occur. 7. It was concluded that the AMA is under control of a closed-loop mechanism with a latency of approximately 23 ms. However, the reflex output has a maximum, depending on information about the food resistance gained in previous cycles.(ABSTRACT TRUNCATED AT 400 WORDS)


2021 ◽  
Vol 108 (Supplement_6) ◽  
Author(s):  
C Maden ◽  
A Lee ◽  
M l Kelly ◽  
Y R Im ◽  
M Barkeji

Abstract Aim Intimate examinations are potentially uncomfortable and embarrassing. In addition to offering chaperones routinely, it is also important to clearly document the circumstances, with implications on patient dignity and safeguarding both patients and staff. We aimed to analyse the quality of chaperone documentation in the breast clinic before and after intervention. Method Audit standards (GMC and Chelsea & Westminster Trust guidelines): [1] Consent [2] Chaperone use/refusal, and [3] Chaperone role and identity should be clearly documented in the notes. We collected breast clinic data prospectively over one week, then re-audited after interventions including teaching sessions to the breast MDT, introduction of electronic (e)-notes (Cerner©), and creation of an instructional video demonstrating how to create an automatic template to easily document the aspects of chaperone use. Results 110 patients’ notes were analysed in the first cycle, and 74 in the second. Documentation improved significantly between cycle 1 and 2 for: consent (0% vs. 38%, p < 0.0001), identity of chaperone (12% vs. 35%, p = 0.0003), and role of chaperone (8% vs. 23%, p = 0.0091). Documentation for chaperone use or refusal improved, but this was not significant (27% vs. 35%, p = 0.3305). Conclusions Documentation improved significantly for most standards, likely due to the template prompting the clinician. However, documentation remains suboptimal. Possible reasons include forgetfulness in a busy clinic, or shortage of staff available to chaperone. Future recommendations include creating a mandatory template on the e-notes for all breast clinic documentation including a section for chaperone use, role, and identity, and providing more staff such as HCAs for the clinic.


Crisis ◽  
2010 ◽  
Vol 31 (3) ◽  
pp. 160-164 ◽  
Author(s):  
Almir Fajkic ◽  
Orhan Lepara ◽  
Martin Voracek ◽  
Nestor D. Kapusta ◽  
Thomas Niederkrotenthaler ◽  
...  

Background: Evidence on youth suicides from Southeastern Europe is scarce. We are not aware of previous reports from Bosnia and Herzegovina, which experienced war from 1992 to 1995. Durkheim’s theory of suicide predicts decreased suicide rates in wartime and increased rates afterward. Aims: To compare child and adolescent suicides in Bosnia and Herzegovina before and after the war. Methods: Data on youth suicide for prewar (1986–90) and postwar (2002–06) periods were analyzed with respect to prevalence, sex and age differences, and suicide methods. Suicide data from 1991 through 2001 were not available. Results: Overall youth suicide rates were one-third lower in the postwar than in the prewar period. This effect was most pronounced for girls, whose postwar suicide rates almost halved, and for 15–19-year-old boys, whose rates decreased by about a one-fourth. Suicides increased among boys aged 14 or younger. Firearm suicides almost doubled proportionally and were the predominant postwar method, while the most common prewar method had been hanging. Conclusions: The findings from this study indicate the need for public education in Bosnia and Herzegovina on the role of firearm accessibility in youth suicide and for instructions on safe storage in households. Moreover, raising societal awareness about suicide risk factors and suicide prevention is needed.


2020 ◽  
Vol 26 ◽  
pp. 41
Author(s):  
Tianxiao Wang

This article is concerned with linear quadratic optimal control problems of mean-field stochastic differential equations (MF-SDE) with deterministic coefficients. To treat the time inconsistency of the optimal control problems, linear closed-loop equilibrium strategies are introduced and characterized by variational approach. Our developed methodology drops the delicate convergence procedures in Yong [Trans. Amer. Math. Soc. 369 (2017) 5467–5523]. When the MF-SDE reduces to SDE, our Riccati system coincides with the analogue in Yong [Trans. Amer. Math. Soc. 369 (2017) 5467–5523]. However, these two systems are in general different from each other due to the conditional mean-field terms in the MF-SDE. Eventually, the comparisons with pre-committed optimal strategies, open-loop equilibrium strategies are given in details.


2018 ◽  
Vol 15 (1) ◽  
pp. 55-72
Author(s):  
Herlin Hamimi ◽  
Abdul Ghafar Ismail ◽  
Muhammad Hasbi Zaenal

Zakat is one of the five pillars of Islam which has a function of faith, social and economic functions. Muslims who can pay zakat are required to give at least 2.5 per cent of their wealth. The problem of poverty prevalent in disadvantaged regions because of the difficulty of access to information and communication led to a gap that is so high in wealth and resources. The instrument of zakat provides a paradigm in the achievement of equitable wealth distribution and healthy circulation. Zakat potentially offers a better life and improves the quality of human being. There is a human quality improvement not only in economic terms but also in spiritual terms such as improving religiousity. This study aims to examine the role of zakat to alleviate humanitarian issues in disadvantaged regions such as Sijunjung, one of zakat beneficiaries and impoverished areas in Indonesia. The researcher attempted a Cibest method to capture the impact of zakat beneficiaries before and after becoming a member of Zakat Community Development (ZCD) Program in material and spiritual value. The overall analysis shows that zakat has a positive impact on disadvantaged regions development and enhance the quality of life of the community. There is an improvement in the average of mustahik household incomes after becoming a member of ZCD Program. Cibest model demonstrates that material, spiritual, and absolute poverty index decreased by 10, 5, and 6 per cent. Meanwhile, the welfare index is increased by 21 per cent. These findings have significant implications for developing the quality of life in disadvantaged regions in Sijunjung. Therefore, zakat is one of the instruments to change the status of disadvantaged areas to be equivalent to other areas.


2020 ◽  
pp. 99-107
Author(s):  
Erdal Sehirli

This paper presents the comparison of LED driver topologies that include SEPIC, CUK and FLYBACK DC-DC converters. Both topologies are designed for 8W power and operated in discontinuous conduction mode (DCM) with 88 kHz switching frequency. Furthermore, inductors of SEPIC and CUK converters are wounded as coupled. Applications are realized by using SG3524 integrated circuit for open loop and PIC16F877 microcontroller for closed loop. Besides, ACS712 current sensor used to limit maximum LED current for closed loop applications. Finally, SEPIC, CUK and FLYBACK DC-DC LED drivers are compared with respect to LED current, LED voltage, input voltage and current. Also, advantages and disadvantages of all topologies are concluded.


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