scholarly journals Motoneurone synchronization for intercostal and abdominal muscles: interneurone influences in two different species

Author(s):  
J. D. Road ◽  
A. T. R. de Almeida ◽  
P. A. Kirkwood

Abstract The contribution of branched-axon monosynaptic inputs in the generation of short-term synchronization of motoneurones remains uncertain. Here, synchronization was measured for intercostal and abdominal motoneurones supplying the lower thorax and upper abdomen, mostly showing expiratory discharges. Synchronization in the anaesthetized cat, where the motoneurones receive a strong direct descending drive, is compared with that in anaesthetized or decerebrate rats, where the direct descending drive is much weaker. In the cat, some examples could be explained by branched-axon monosynaptic inputs, but many others could not, by virtue of peaks in cross-correlation histograms whose widths (relatively wide) and timing indicated common inputs with more complex linkages, e.g., disynaptic excitatory. In contrast, in the rat, correlations for pairs of internal intercostal nerves were dominated by very narrow peaks, indicative of branched-axon monosynaptic inputs. However, the presence of activity in both inspiration and expiration in many of the nerves allowed additional synchronization measurements between internal and external intercostal nerves. Time courses of synchronization for these often consisted of combinations of peaks and troughs, which have never been previously described for motoneurone synchronization and which we interpret as indicating combinations of inputs, excitation of one group of motoneurones being common with either excitation or inhibition of the other. Significant species differences in the circuits controlling the motoneurones are indicated, but in both cases, the roles of spinal interneurones are emphasised. The results demonstrate the potential of motoneurone synchronization for investigating inhibition and have important general implications for the interpretation of neural connectivity measurements by cross-correlation.

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Eray Gemici ◽  
Müslüm Polat

Purpose This study aims to examine the volatility spillovers between Bitcoin (BTC), Litecoin (LTC) and Ethereum (ETH) as they are related to structural breaks. Design/methodology/approach This study examines the daily period from August 7, 2015 to July 10, 2018 by conducting causality-in-mean and causality-in-variance tests among cryptocurrencies. Findings The findings showed that there was one-way causality-in-mean from BTC to LTC and ETH, but there was no causality-in-mean from LTC and ETH to BTC. On the other hand, considering the structural breaks included in the variance equations, the estimation results showed that there were short-term causality-in-variance from LTC to BTC and long-term causality-in-variance from BTC to LTC. Originality/value This study fills the gap by contributing in two ways. First, to the best of the authors’ knowledge, this is the first study that used the cross-correlation function (CCF) of causality to explore causality-in-variance among cryptocurrencies. Second, this study considers the structural breaks in variance in the return series.


Author(s):  
Stefan Scherbaum ◽  
Simon Frisch ◽  
Maja Dshemuchadse

Abstract. Folk wisdom tells us that additional time to make a decision helps us to refrain from the first impulse to take the bird in the hand. However, the question why the time to decide plays an important role is still unanswered. Here we distinguish two explanations, one based on a bias in value accumulation that has to be overcome with time, the other based on cognitive control processes that need time to set in. In an intertemporal decision task, we use mouse tracking to study participants’ responses to options’ values and delays which were presented sequentially. We find that the information about options’ delays does indeed lead to an immediate bias that is controlled afterwards, matching the prediction of control processes needed to counter initial impulses. Hence, by using a dynamic measure, we provide insight into the processes underlying short-term oriented choices in intertemporal decision making.


2018 ◽  
pp. 49-68 ◽  
Author(s):  
M. E. Mamonov

Our analysis documents that the existence of hidden “holes” in the capital of not yet failed banks - while creating intertemporal pressure on the actual level of capital - leads to changing of maturity of loans supplied rather than to contracting of their volume. Long-term loans decrease, whereas short-term loans rise - and, what is most remarkably, by approximately the same amounts. Standardly, the higher the maturity of loans the higher the credit risk and, thus, the more loan loss reserves (LLP) banks are forced to create, increasing the pressure on capital. Banks that already hide “holes” in the capital, but have not yet faced with license withdrawal, must possess strong incentives to shorten the maturity of supplied loans. On the one hand, it raises the turnovers of LLP and facilitates the flexibility of capital management; on the other hand, it allows increasing the speed of shifting of attracted deposits to loans to related parties in domestic or foreign jurisdictions. This enlarges the potential size of ex post revealed “hole” in the capital and, therefore, allows us to assume that not every loan might be viewed as a good for the economy: excessive short-term and insufficient long-term loans can produce the source for future losses.


2019 ◽  
Vol 9 (1) ◽  
pp. 53-66 ◽  
Author(s):  
Dandan Irawan

Basically a natural partnership will achieve its goal if mutual requirements, mutual reinforcement, and mutual benefit can be maintained and made a strong fundamental commitment among partners. Nevertheless the development seems very slow. The cause is the presence of specific and different conditions and structure factors compared to other countries. Along with that, we still encounter various forms of gaps, such as inequality among regions, among income groups, between sectors, among economic actors, and so forth. The next problem is that in business entities including cooperatives and micro and small enterprises in running their business activities requires business partnerships with medium and large enterprises in order to improve business performance and business scale. While on the other hand our economic conditions and structures are not yet fully conducive to fostering partnerships based on purely business considerations or competitive market motivations but the business partnership of the foundation is strong enough in our country's constitution. Partnerships will work if partners are equally benefiting. Our concept of partnership is like that, although in the short term, there is a party or a party benefiting more from the other side.


2011 ◽  
Vol 29 (supplement) ◽  
pp. 283-304 ◽  
Author(s):  
Timothy R. Brick ◽  
Steven M. Boker

Among the qualities that distinguish dance from other types of human behavior and interaction are the creation and breaking of synchrony and symmetry. The combination of symmetry and synchrony can provide complex interactions. For example, two dancers might make very different movements, slowing each time the other sped up: a mirror symmetry of velocity. Examining patterns of synchrony and symmetry can provide insight into both the artistic nature of the dance, and the nature of the perceptions and responses of the dancers. However, such complex symmetries are often difficult to quantify. This paper presents three methods – Generalized Local Linear Approximation, Time-lagged Autocorrelation, and Windowed Cross-correlation – for the exploration of symmetry and synchrony in motion-capture data as is it applied to dance and illustrate these with examples from a study of free-form dance. Combined, these techniques provide powerful tools for the examination of the structure of symmetry and synchrony in dance.


1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.


Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3678
Author(s):  
Dongwon Lee ◽  
Minji Choi ◽  
Joohyun Lee

In this paper, we propose a prediction algorithm, the combination of Long Short-Term Memory (LSTM) and attention model, based on machine learning models to predict the vision coordinates when watching 360-degree videos in a Virtual Reality (VR) or Augmented Reality (AR) system. Predicting the vision coordinates while video streaming is important when the network condition is degraded. However, the traditional prediction models such as Moving Average (MA) and Autoregression Moving Average (ARMA) are linear so they cannot consider the nonlinear relationship. Therefore, machine learning models based on deep learning are recently used for nonlinear predictions. We use the Long Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) neural network methods, originated in Recurrent Neural Networks (RNN), and predict the head position in the 360-degree videos. Therefore, we adopt the attention model to LSTM to make more accurate results. We also compare the performance of the proposed model with the other machine learning models such as Multi-Layer Perceptron (MLP) and RNN using the root mean squared error (RMSE) of predicted and real coordinates. We demonstrate that our model can predict the vision coordinates more accurately than the other models in various videos.


1961 ◽  
Vol 200 (6) ◽  
pp. 1197-1202 ◽  
Author(s):  
Hiroshi Kuida ◽  
Robert P. Gilbert ◽  
Lerner B. Hinshaw ◽  
Joel G. Brunson ◽  
Maurice B. Visscher

Studies were made in 5 monkeys, 7 rabbits, and 33 cats of the effect of gram-negative endotoxin on aortic, pulmonary artery (PAP), and portal venous (PVP) pressures; and on changes in weight of a short segment of intestine. Studies of blood pooling were also made in 12 cats. The responses in these species were compared with those previously observed in the dog. Although variable degrees of hypotension developed at one time or another in all animals following injection of endotoxin, the early precipitous hypotension that characteristically occurs in the dog was observed only in the cat. However, in this species the dramatic fall in pressure could be ascribed to pulmonary vascular constriction and acute right ventricular hypertension and failure, and not to splanchnic pooling. PAP also became elevated in the monkey and the rabbit, but usually was of lesser magnitude and did not appear to explain the development of the relatively late hypotension that occurred in these species. The absence of significant increases in gut weight and the minor increments in PVP in all animals indicate that in none of these species is hepatic vein constriction and splanchnic pooling a significant mechanism in producing early shock as it is in the dog. Pathologic gross and microscopic studies in the monkey and gross examinations in the other species supported this conclusion.


1982 ◽  
Vol 62 (4) ◽  
pp. 1199-1209 ◽  
Author(s):  
V. A. POUTEAUX ◽  
G. I. CHRISTISON ◽  
C. S. RHODES

Two experiments were conducted to evaluate the involvement of dietary protein and short-term chilling on the incidence of diarrhea and on transit time of digesta in pigs weaned at 3–4 wk of age. The three protein sources used were buttermilk powder (BMP), soybean meal (SBM) or pea protein concentrate (PPC), which provided 85% of the dietary protein. In exp. 1, 72 pigs were exposed to a 16 °C decrease in ambient temperature for 8 h on day 4 of a 9-day feeding trial; 72 pigs were not chilled. The pigs on the PPC diet gained less (539 g) (P < 0.05) than pigs on BMP (1183 g) or SBM (952 g) although intakes were similar. Neither diet nor chilling affected fecal moisture content or the incidence of diarrhea. The PPC ration increased (P < 0.05) transit time (slowed rate of passage) on day 8. Chilling on day 4 decreased (P < 0.05) transit time (18.7 vs. 25.6 h) on that day. Neither protein source nor chilling caused differences in total or coliform bacteria isolated from fecal samples on blood agar or MacConkey's agar. In exp. 2, eight chilled and nine control pigs were euthanized and the quantity of three markers in six segments of the gastrointestinal tract was determined. The PPC diet passed more slowly than the other diets. In chilled pigs, the chromic oxide front was closer to the anus, indicating an increased rate of passage. It was concluded that the severity of the cold exposure was not suffficient to induce diarrhea and that there was no interaction between the effects of chilling and of dietary protein. There was, however, a tendency for chilling to increase the rate of passage of digesta which could have an additive effect on the severity of nutritional diarrhea. Key words: Pigs, weaning, diarrhea, protein, cold, transit time.


2021 ◽  
Vol 50 (1) ◽  
Author(s):  
Julia R. Lazzari-Dean ◽  
Anneliese M.M. Gest ◽  
Evan W. Miller

Membrane potential (Vmem) is a fundamental biophysical signal present in all cells. Vmem signals range in time from milliseconds to days, and they span lengths from microns to centimeters. Vmem affects many cellular processes, ranging from neurotransmitter release to cell cycle control to tissue patterning. However, existing tools are not suitable for Vmem quantification in many of these areas. In this review, we outline the diverse biology of Vmem, drafting a wish list of features for a Vmem sensing platform. We then use these guidelines to discuss electrode-based and optical platforms for interrogating Vmem. On the one hand, electrode-based strategies exhibit excellent quantification but are most effective in short-term, cellular recordings. On the other hand, optical strategies provide easier access to diverse samples but generally only detect relative changes in Vmem. By combining the respective strengths of these technologies, recent advances in optical quantification of absolute Vmem enable new inquiries into Vmem biology. Expected final online publication date for the Annual Review of Biophysics, Volume 50 is May 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


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