Role of lung inflation in control of air breath duration in African lungfish (Protopterus annectens)

1992 ◽  
Vol 262 (5) ◽  
pp. R879-R884 ◽  
Author(s):  
A. I. Pack ◽  
R. J. Galante ◽  
A. P. Fishman
Keyword(s):  
Tidal Volume ◽  
Neural Circuits ◽  
Inspiratory Time ◽  
Timing Control ◽  
Lung Inflation ◽  
Protopterus Annectens ◽  
African Lungfish ◽  
The Relationship ◽  
Different Levels

Studies were conducted in the African lungfish (Protopterus annectens) to investigate the role of lung inflation on control of the duration of the lung breath. The studies were done in decerebrate spinalectomized animals. Two types of tests were performed: 1) a no-inflation test (airway occluded) in which the lungs were not inflated during an air breath, and 2) an inflation test in which the lungs were inflated at the onset of the lung breath to different levels of intrapulmonary pressure (2.5, 5.0, 7.5, and 10.0 cmH2O). Lung inflation shortened the duration of the lung breath. The relationship between intrapulmonary pressure and breath duration was curvilinear and similar to the relationship between tidal volume and inspiratory duration in mammals. Likewise, the relationship could be described by a hyperbola with a linear relationship between intrapulmonary pressure and the inverse of breath duration. This relationship was essentially not affected by changing the composition of the gas used to inflate the lungs: air, oxygen, or nitrogen. Vagotomy, however, largely abolished the effect of lung inflation on breath duration. Because there is such similarity between these results and effect of lung inflation on control of inspiratory time in mammals, it is postulated that neural circuits for control of respiratory timing were already developed and similar in the lungfish. Because the muscles used in the lungfish to ventilate the lung are totally different (buccal force pump) from those in mammals, the neural circuits for timing control and those for shaping the pattern of motor output appear to be separate.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Religiosity as a factor protecting against problem behaviour in adolescence

2015 ◽  
Vol 21 (1-2) ◽  
pp. 63-89
Author(s):  
Iwona Niewiadomska ◽  
Rafał P. Bartczuk ◽  
Joanna Chwaszcz ◽  
Stanisław Fel ◽  
Weronika Augustynowicz ◽  
...  
Keyword(s):  
Problem Behaviour ◽  
Problem Behaviours ◽  
Upper Secondary ◽  
The Impact ◽  
The Relationship ◽  
Moderating Role ◽  
Upper Secondary Schools ◽  
Conceptual Work ◽  
Different Levels

Abstract This article explores the question, to what degree religiosity contributes, as a protecting factor against a broad category of socially deviant adolescent and youth behaviours. It also tests the hypothesis that gender plays a moderating role in the relationship between religiosity and problem behaviour. It employs a modified version of the Problem Behaviour Syndrome Measure (PBSM), in concert with Jessor and Jessor’s conceptual work. It also makes use of the Duke Religion Index (DUREL) to assess religiosity. The empirical study deals with a representative group of 960 students of upper-secondary schools in the Lubelskie province, Poland. The results were analyzed using canonical analysis and ANOVA. The achievements of the article are twofold. First, it identifies significant correlations between the different levels of religiosity among youth, and the occurrence and intensification of problem behaviours, particularly in regard to organized activity. Organized and intrinsic religiosity play principal protective roles, while the impact of personal religious practices is less significant. Secondly, while analyzing the moderating role of gender in the relationship between religiosity and the intensity of problem behaviour, it was found that gender does not have a significant interactive impact. An affirmative conclusion was confirmed in only two instances.

Role of N-methyl-D-aspartate receptors in the pontine pneumotaxic mechanism in the cat

1994 ◽  
Vol 76 (3) ◽  
pp. 1138-1143 ◽  
Author(s):  
L. Ling ◽  
D. R. Karius ◽  
D. F. Speck
Keyword(s):  
Nmda Receptor ◽  
Nmda Receptors ◽  
Partial Recovery ◽  
Inspiratory Time ◽  
Systemic Injection ◽  
Lung Inflation ◽  
Mk 801 ◽  
Efferent Limb ◽  
Adult Cats

Systemic injection of MK-801, an N-methyl-D-aspartate (NMDA) receptor-associated channel blocker, induces an apneusis in vagotomized cats similar to that produced by pontine respiratory group (PRG) lesions, suggesting the possible involvement of NMDA receptors in the pontine pneumotaxic mechanism. Previous results from our laboratory indicate that the efferent limb of the pontine pneumotaxic mechanism is unlikely to require NMDA receptor-mediated neurotransmission. Therefore, the present study examined the potential involvement of PRG NMDA receptors in the pontine pneumotaxic mechanism. Experiments were conducted in decerebrate, paralyzed, and ventilated adult cats. The effects on inspiratory time (TI) of MK-801 microinjection into PRG were tested in 12 cats. Pressure microinjection of MK-801 (15 mM, 80–3,000 nl) significantly prolonged TI in all animals when lung inflation was withheld. TI progressively increased in most animals for > or = 30 min. After this period, partial recovery of the effect occurred in eight cats as TI shortened toward predrug levels. In three animals, microinjection of MK-801 induced a complete apneusis in the absence of lung inflation from which there was no detectable recovery. Microinjections into regions approximately 2 mm distant from PRG produced little or no effect. These results provide evidence that NMDA receptors located in the region of PRG play an important functional role in the control of the breathing cycle.

The role of brand personality in the formation of consumer affect and self-brand connection

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Justin F. McManus ◽  
Sergio W. Carvalho ◽  
Valerie Trifts
Keyword(s):  
Personality Traits ◽  
Design Methodology ◽  
Brand Personality ◽  
Content Type ◽  
Mediation Analyses ◽  
Within Subjects ◽  
The Relationship ◽  
Different Levels ◽  
Brand Personality Traits

Purpose This study aims to explore the role of brand personality traits in explaining how different levels of brand favorability evoke affect from and forge connections to consumers. Design/methodology/approach The authors used a quantitative approach consisting of within-subjects (Study 1) and between-subjects (Study 2) experimental designs. Mediation analyses were tested using OLS regression with the MEMORE and PROCESS macros. Findings Findings suggest increases in brand excitement and sincerity to be related to differences in positive affect evoked by favorable and unfavorable brands; decreases in brand sincerity to be related to differences in negative affect between favorable and unfavorable brands (Study 1); brand competence and excitement to be related to the relationship between brand favorability and self-brand connection; and brand competence and excitement to best distinguish favorable brands from unfavorable brands (Study 2). Originality/value These results support the importance of brand personality traits that are considered to be universally positive and provide managers with an initial roadmap for which brand personality traits should be prioritized when communicating with consumers.

Brain hypoxia and control of breathing: role of the vagi

1982 ◽  
Vol 53 (1) ◽  
pp. 212-217 ◽  
Author(s):  
R. W. Chapman ◽  
T. V. Santiago ◽  
N. H. Edelman
Keyword(s):  
Ventilatory Response ◽  
Control Of Breathing ◽  
Inspiratory Time ◽  
Small Magnitude ◽  
Lung Inflation ◽  
Brain Hypoxia ◽  
And Control ◽  
Respiratory Responses ◽  
Spontaneous Breath

Vagally mediated reflexes play an important role in the generation of respiratory responses to various stimuli. This study examined the role of vagally mediated mechanisms in the generation of the respiratory responses to progressive brain hypoxia secondary to carboxyhemoglobinemia (HbCO 013;55%) in six unanesthetized goats. Ventilation, respiratory cycle timing, and the lung inflation reflex were measured before and during CO inhalation in intact and bilaterally vagotomized animals. Our results indicate that vagal reflexes contribute a small magnitude of the hyperpnea caused by carboxyhemoglobinemia. Furthermore, in contrast to that reported for CO2 inhalation, the tachypneic nature of the ventilatory response to CO is not a vagally mediated phenomenon. CO inhalation had a biphasic influence on the strength of the lung inflation reflex measured as the ratio of inspiratory time during occlusion (TIoccl) to inspiratory time of the preceding spontaneous breath (TIspont). At HbCO levels of 35%, TIoccl/TIspont was enhanced, whereas at HbCO levels of 55% of ratio fell to unity, indicating abolition of the reflex. After vagotomy, this ratio was unity at all levels of carboxyhemoglobinemia.

scholarly journals Corruption and satisfaction with democracy: the conditional role of electoral disproportionality and ballot control

2018 ◽  
Vol 10 (3) ◽  
pp. 393-416 ◽  
Author(s):  
Alessandro Pellegata ◽  
Vincenzo Memoli
Keyword(s):  
Electoral Systems ◽  
Aggregate Level ◽  
Negative Effects ◽  
Empirical Results ◽  
Satisfaction With Democracy ◽  
Level Data ◽  
The Impact ◽  
The Relationship ◽  
Different Levels

Existing literature has analysed the relationship between electoral systems and either corruption or satisfaction with democracy (SWD) focussing on the traditional distinction between majoritarian and proportional systems. This paper, instead, investigates if and how specific aspects of electoral systems moderate the negative effects of corruption perceptions on SWD. We argue that two mechanisms act simultaneously but at different levels. The first mechanism is the relationship between voters and the national government, while the second links single representatives to their constituents. We advance conditional hypotheses that postulate an attenuating effect of disproportionality and a reinforcing impact of personal vote. Empirical results from 35 elections in 33 democracies, using both individual and aggregate-level data, confirm the research hypotheses. More disproportional electoral systems weaken the impact of citizens’ perceived corruption on their democratic satisfaction, while this is strengthened by systems in which the ballot control is mostly in the hand of the voters.

scholarly journals Stability of the Mitigating Effect of Students’ Perceived Teacher Enthusiasm on Class-related Boredom: Moderating Role of Boredom Proneness and Perceived Task Difficulty

2020 ◽  
Vol 17 (8) ◽  
pp. 2645 ◽  
Author(s):  
Chen Wang ◽  
Yunjun Hu ◽  
Xia Zhang ◽  
Jing Wang ◽  
Guangli Cui ◽  
...  
Keyword(s):  
Task Difficulty ◽  
Learning And Teaching ◽  
Teacher Enthusiasm ◽  
Boredom Proneness ◽  
The Stability ◽  
The Relationship ◽  
Moderating Role ◽  
Different Levels

The aim of the current study was to explore the stability of the mitigating effect of students’ perceived teacher enthusiasm on class-related boredom and the moderating role of boredom proneness and perceived task difficulty in such effect. A total of 984 students from five universities in China participated in the study. Questionnaires on class-related boredom, perceived teacher enthusiasm, boredom proneness, and perceived task difficulty were used to measure the respective variables. Results showed that boredom proneness and perceived task difficulty significantly moderated the relationship between perceived teacher enthusiasm and class-related boredom. Moreover, when considering perceived task difficulty, boredom proneness became silent in the moderating path between perceived teacher enthusiasm and class-related boredom. Even so, the mitigating effect of students’ perceived teacher enthusiasm on class-related boredom was stable in students with different levels of boredom proneness and perceived task difficulty. The implications for learning and teaching are discussed.

Interactive effects of CO2 and upper airway negative pressure on breathing pattern

1987 ◽  
Vol 63 (1) ◽  
pp. 229-237 ◽  
Author(s):  
E. van Lunteren
Keyword(s):  
Tidal Volume ◽  
Respiratory Rate ◽  
Negative Pressure ◽  
Upper Airway ◽  
Interactive Effects ◽  
Inspiratory Time ◽  
Diaphragm Electrical Activity ◽  
Wide Range ◽  
Inspiratory Activity ◽  
The Relationship

The interactive effects of upper airway negative pressure and hypercapnia on the pattern of breathing were assessed in pentobarbital-anesthetized cats. At any given level of pressure in the upper airway, hypercapnia increased respiratory rate, reduced inspiratory time, and augmented tidal volume, inspiratory airflow, and the peak and rate of rise of diaphragm electrical activity. Conversely, at any given level of CO2, upper airway negative pressure decreased respiratory rate, prolonged inspiratory time, and depressed inspiratory airflow and diaphragm electromyogram (EMG) rate of rise. Application of negative pressure to the upper airway shifted the relationship between tidal volume and inspiratory time upward and rightward. The relationship between inspiratory and expiratory times, however, was linearly correlated over a wide range of chemical drives and levels of upper airway pressure. These results suggest that in the anesthetized cat upper airway negative pressure afferent inputs 1) interact in an additive fashion with hypercapnia to alter the pattern of breathing, 2) interact multiplicatively with CO2 to influence mean inspiratory airflow and diaphragm EMG rate of rise, 3) depress the generation of central inspiratory activity, 4) increase the time-dependent volume threshold for inspiratory termination, and 5) affect the ratio between inspiratory and expiratory times in a similar manner as alterations in PCO2.

THE ROLE OF EXOGENOUS FACTORS IN THE FOREST BIOTA FORMATION

2015 ◽  
Vol 10 (2) ◽  
pp. 105-109 ◽  
Author(s):  
Курбанова ◽  
Saniya Kurbanova ◽  
Глушко ◽  
Sergey Glushko ◽  
Прохоренко ◽  
...  
Keyword(s):  
Adaptive Strategy ◽  
Forest Sites ◽  
Different Types ◽  
Exogenous Factors ◽  
Relationship Of ◽  
The Relationship ◽  
Further Development ◽  
Biological Component ◽  
Different Levels

Forest sites are formed in the interaction of heterogeneous components of biogeosystem. The increase or decrease of biological component in forest biogeosystems defines the different types of strategy with opposite characteristics, representing the different lines of adaptation (to the biological medium and abiotic environment). The manifestation of adaptive strategy requires appropriate tools, which are evolving on the basis of accumulated property (information capacity) and prevailing forest sites. Forest sites can be seen as an external “order” on the evolution of adaptations. Silvicultural properties of forest biological systems work enough in the interaction of different forms of matter (biological, abiotic), mapping out a hierarchy of biogeosystems. The information potential of forest biota interconnects different levels of systemic organization of forest biogeosystems. Further development of biogeocenology and the theory and ecosystems will allow to investigate the relationship of forest biota with exogenous forest-forming factors.

Investigating the Relationship Between Nonword Repetition Performance and Syllabic Structure in Typical and Atypical Language Development

2013 ◽  
Vol 56 (2) ◽  
pp. 708-720 ◽  
Author(s):  
Marco Tamburelli ◽  
Gary Jones
Keyword(s):  
Language Impairment ◽  
Specific Language Impairment ◽  
Syllable Structure ◽  
Nonword Repetition ◽  
Typically Developing ◽  
Syllabic Structure ◽  
The Relationship ◽  
Phonological Complexity ◽  
Different Levels

Purpose In this study, the authors examined the role of syllabic structure in nonword repetition performance in typically developing (TD) children and children with specific language impairment (SLI). Method Eighteen children with SLI (5;7–6;7 [years;months]) and 18 TD children matched for chronological age were tested on their ability to repeat phonemes in different positions within syllable structure (onset, nucleus, coda). The test involved 2 separate nonword repetition tasks differing in lexicality (high vs. low). High-lexicality nonwords contained subparts that are morphemes of the language (i.e., subparts were “lexical”), whereas nonlexical nonwords did not. Results Repetition performance across the 3 syllabic positions showed a significant effect for both populations and on both tasks. However, although on the high-lexicality task the direction of the effect revealed the onset as the most error-prone constituent (onset > coda > nucleus), on the low-lexicality task, it was the coda that attracted most errors (coda > onset > nucleus). Conclusions Results suggest that the procedures involved in computing syllabic structure are qualitatively similar in the 2 populations. We take these results to support the view that different syllabic positions involve different levels of phonological complexity and that tests that control for lexicality are crucial in illuminating these differences.

The Role of Relative Intrinsic Aspirations in Chinese Adolescents’ Prosocial Behaviors

2015 ◽  
Vol 50 (1) ◽  
pp. 75-92 ◽  
Author(s):  
Xinyuan Fu ◽  
Xiaolan Liu ◽  
Ying Yang ◽  
Mengyuan Zhang ◽  
Yu Kou
Keyword(s):  
Decision Making ◽  
Chinese Adolescents ◽  
Prosocial Behaviors ◽  
Self And Other ◽  
Prosocial Tendencies ◽  
The Relationship ◽  
Different Levels ◽  
Intrinsic Aspirations

We examined Chinese adolescents’ aspirations and explored the relationship between relative intrinsic aspirations (RIA) and prosocial behaviors and whether adolescents with different levels of RIA have different emphases on self- and other-oriented considerations during prosocial decision making. In Study 1, 236 participants were recruited and completed a questionnaire containing the Aspiration Index and Prosocial Tendencies Measure. The results show that RIA are positively associated with adolescents’ prosocial behaviors. In Study 2, 158 adolescents completed a questionnaire containing the Aspiration Index and measurements of prosocial decision making and considerations in prosocial decision making. To some extent, adolescents with a lower level of RIA have a greater emphasis on self-oriented considerations, whereas adolescents with a higher level of RIA have a greater emphasis on other-oriented considerations. In addition, both studies suggest that Chinese adolescents value intrinsic aspirations above extrinsic ones.

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