scholarly journals Hormonal and Pheromonal Regulation of Reproduction in the Bumble Bee Bombus terrestris

1994 ◽  
Author(s):  
Abraham Hefetz ◽  
Gene Robinson
Keyword(s):  
Ovarian Development ◽  
Bombus Terrestris ◽  
Worker Reproduction ◽  
Colony Development ◽  
Social Species ◽  
Before And After ◽  
High Aggression ◽  
Total Body ◽  
Virgin Queens ◽  
The Brain

Bombus terrestris constitute important pollinators of greenhouse crops. In Israel the species utilized is, whose colonies are reared commercially. This is a primitively social species with a particular colony development. It encompasses two social phases: a eusocial phase in which the queen dominates reproduction, and a competition phase in which workers compete with the queen for the parentage of males. These workers are distinguished by accelerated ovarian development, high production of JH, and elevated levels of dopamine in the brain. Queen-worker conflict is also manifested in overt aggression among all members of the nest. High aggression is correlated with dominance status of the bees and is also correlated with octopamine levels in the brain. After verifying that JH III is the only JH produced by the bees and validating the assay for its measurements (RCA & RIA), we used JH as an indicator of worker reproduction. Queens taken from colonies both before and after the competition phase were equally effective in inhibiting worker reproduction. Moreover, there is only a narrow window, around the competition point, in which workers may have the opportunity to initiate reproduction. Before that point they are inhibited by the dominant queen, while after that point both the queen and those workers with accelerated ovarian development exert strong inhibition on worker nest mates. Thus, "queen dominance deterioration" is not the primary cause in eliciting the queen-worker conflict. Queens convey their presence by means of a chemical signal that is extractable in organic solvent and that is normally spread on the cuticle. Total body extract and body washes, applied on dead virgin queens, were able to inhibit the release of JHin vitro in queenless workers. However, none of the prominent exocrine gland investigated mimicked this function. It is possible that the source of the putative pheromone is an unknown gland, or that it emanates from an assembly of glands. Chemical analyses of the prominent glands revealed a plethora of compounds the function of which should be further investigated. Understanding the social behavior of B. terrestris paves the way to facilitate colony manipulation and to adjust the colonies for specific pollination requirements.

scholarly journals Worker-Born Males Are Smaller but Have Similar Reproduction Ability to Queen-Born Males in Bumblebees

Insects ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1008
Author(s):  
Huiyue Zhao ◽  
Yanjie Liu ◽  
Hong Zhang ◽  
Tom D. Breeze ◽  
Jiandong An
Keyword(s):  
Bombus Terrestris ◽  
Morphological Characteristics ◽  
Worker Reproduction ◽  
Egg Laying ◽  
Colony Development ◽  
Eusocial Insects ◽  
Reproductive Ability ◽  
Evolution Of Sociality ◽  
Sperm Counts ◽  
Virgin Queens

Queen-worker conflict over the reproduction of males exists in the majority of haplodiplioidy hymenpteran species such as bees, wasps, and ants, whose workers lose mating ability but can produce haploid males in colony. Bumblebee is one of the representatives of primitively eusocial insects with plastic division labor and belongs to monandrous and facultative low polyandry species that have reproductive totipotent workers, which are capable of competing with mother queen to produce haploid males in the queenright colony compared to higher eusocial species, e.g., honeybees. So, bumblebees should be a better material to study worker reproduction, but the reproductive characteristics of worker-born males (WMs) remain unclear. Here, we choose the best-studied bumblebee Bombus terrestris to evaluate the morphological characteristics and reproductive ability of WMs from the queenless micro-colonies. The sexually matured WMs showed smaller in forewing length and weight, relatively less sperm counts but equally high sperm viability in comparison with the queen-born males (QMs) of the queenright colony. Despite with smaller size, the WMs are able to successfully mate with the virgin queens in competition with the QMs under laboratory conditions, which is quite different from the honeybees reported. In addition, there was no difference in the colony development, including the traits such as egg-laying rate, colony establishment rate, and populations of offspring, between the WM- and the QM-mated queens. Our study highlights the equivalent reproductive ability of worker-born males compared to that of queens, which might exhibit a positive application or special use of bumblebee rearing, especially for species whose males are not enough for copulation. Further, our finding contributes new evidence to the kin selection theory and suggests worker reproduction might relate to the evolution of sociality in bees.

scholarly journals Nest wax triggers worker reproduction in the bumblebee Bombus terrestris

2016 ◽  
Vol 3 (1) ◽  
pp. 150599 ◽  
Author(s):  
Ann-Marie Rottler-Hoermann ◽  
Stefan Schulz ◽  
Manfred Ayasse
Keyword(s):  
Ovarian Development ◽  
Bombus Terrestris ◽  
Worker Reproduction ◽  
Colony Development ◽  
Essential Information ◽  
Proximate Mechanisms ◽  
The Social ◽  
Dominance Behaviour ◽  
High Level ◽  
Primitively Eusocial

Social insects are well known for their high level of cooperation. Workers of the primitively eusocial bumblebee Bombus terrestris are able to produce male offspring in the presence of a queen. Nonetheless, they only compete for reproduction, in the so-called competition phase, when the workforce is large enough to support the rearing of reproductives. So far, little is known about the proximate mechanisms underlying the shift between altruism and selfish behaviour in bumblebee workers. In this study, we have examined the influence of chemical cues from the nest wax on the onset of worker reproduction. Chemical analyses of wax extracts have revealed that the patterns and amounts of cuticular lipids change considerably during colony development. These changes in wax scent mirror worker abundance and the presence of fertile workers. In bioassays with queen-right worker groups, wax affects the dominance behaviour and ovarian development of workers. When exposed to wax from a colony in competition phase, workers start to compete for reproduction. We suggest that wax scent enables workers to time their reproduction by providing essential information concerning the social condition of the colony.

Ventilatory acclimatization to hypoxia is not dependent on arterial hypoxemia

1985 ◽  
Vol 58 (6) ◽  
pp. 1874-1880 ◽  
Author(s):  
M. A. Busch ◽  
G. E. Bisgard ◽  
H. V. Forster
Keyword(s):  
Partial Pressure ◽  
Carotid Body ◽  
Acute Hypoxia ◽  
Arterial System ◽  
Arterial Pco2 ◽  
Partial Restoration ◽  
Arterial Hypoxemia ◽  
Before And After ◽  
Total Body ◽  
The Brain

Goats were prepared so that one carotid body (CB) could be perfused with blood in which the gas tensions could be controlled independently from the blood perfusing the systemic arterial system, including the brain. Since one CB is functionally adequate, the nonperfused CB was excised. To determine whether systemic arterial hypoxemia is necessary for ventilatory acclimatization to hypoxia (VAH), the CB was perfused with hypoxic normocapnic blood for 6 h [means +/- SE: partial pressure of carotid body O2 (PcbO2), 40.6 +/- 0.3 Torr; partial pressure of carotid body CO2 (PcbCO2), 38.8 +/- 0.2 Torr] while the awake goat breathed room air to maintain systemic arterial normoxia. In control periods before and after CB hypoxia the CB was perfused with hyperoxic normocapnic blood. Changes in arterial PCO2 (PaCO2) were used as an index of changes in ventilation. Acute hypoxia (0.5 h of hypoxic perfusion) resulted in hyperventilation sufficient to reduce average PaCO2 by 6.7 Torr from control (P less than 0.05). Over the subsequent 5.5 h of hypoxic perfusion, average PaCO2 decreased further, reaching 4.8 Torr below that observed acutely (P less than 0.05). Acute CB hyperoxic perfusion (20 min) following 6 h of hypoxia resulted in only partial restoration of PaCO2 toward control values; PaCO2 remained 7.9 Torr below control (P less than 0.05). The progressive hyperventilation that occurred during and after 6 h of CB hypoxia with concomitant systemic normoxia is similar to that occurring with total body hypoxia. We conclude that systemic (and probably brain) hypoxia is not a necessary requisite for VAH.

scholarly journals Effects of Heat Stress on Mating Behavior and Colony Development in Bombus terrestris (Hymenoptera: Apidae)

2021 ◽  
Vol 9 ◽  
Author(s):  
Kimberly Przybyla ◽  
Denis Michez ◽  
Ella Zambra ◽  
Abigaël Anselmo ◽  
Elise Hennebert ◽  
...  
Keyword(s):  
Heat Waves ◽  
Bombus Terrestris ◽  
Heat Exposure ◽  
Colony Development ◽  
Experimental Protocol ◽  
Sensitive Species ◽  
Copulation Behavior ◽  
And Control ◽  
Virgin Queens ◽  
The Impact

Climate change is related to an increase in the frequency and intensity of extreme events such as heatwaves. In insect pollinators, heat exposure is associated with direct physiological perturbations, and in several species, could lead to a decrease of fitness related to a decrease in fertility. Here we developed a new experimental protocol in controlled conditions to assess if the exposure to high temperatures could modify the attractiveness and fertility of Bombus terrestris males. Our results show that virgin queens of B. terrestris do not have preferences between the pheromonal secretions of heat-exposed and control males. Moreover, mating with a heat-exposed male has no impact on the copulation behavior and the development of the nest (brood composition). We advise to extend trials to cover a range of wild and heat-sensitive species on multiple generations to better understand the impact of heat waves on the bumblebee communities.

PENGARUH PIJAT BAYI TERHADAP KUALITAS TIDUR BAYI UMUR 0 – 3 BULAN DI WILAYAH KERJA PUSKESMAS SOSIAL PALEMBANG TAHUN 2016

2019 ◽  
Vol 6 (2) ◽  
Author(s):  
Juliana Widyastuti Wahyuningsih Juliana Widyastuti Wahyuningsih
Keyword(s):  
Experimental Design ◽  
Growth And Development ◽  
Sampling Technique ◽  
P Value ◽  
Development Phase ◽  
Quality Of Sleep ◽  
Infant Massage ◽  
Before And After ◽  
The Brain

ABSTRAK Tidur merupakan kebutuhan yang harus terpenuhi terutama pada fase perkembangan karena selama tidur akan terjadi perkembangan otak maupun tubuh, sehingga gangguan tidur merupakan masalah yang akan menimbulkan dampak buruk terhadap pertumbuhan dan perkembangan bayi. Kualitas tidur bayi yang baik dapat diciptakan dengan memberikan pemijatan bayi secara rutin. Penelitian ini bertujuan untuk membuktikan bahwa pemijatan dapat mempengaruhi kualitas tidur bayi umur 0-3 bulan. Penelitian ini menggunakan desain penelitian Quasy Eksperimental dengan metode One Group Pretest-Postest. Sampel 22 bayi yang dipilih dengan tehnik Total Sampling yang di observasi sebelum dan sesudah diberikan pemijatan. Variabel yang diukur dalam penelitian ini adalah kualitas tidur bayi 0-3 bulan. Hasil penelitian menunjukkan bahwa ada pengaruh pijat bayi terhadap kualitas tidur bayi umur 0-3 bulan (p value  0,008 < α = 0,05).Berdasarkan hasil penelitian ini disarankan agar keluarga dan masyarakat memberikan pemijatan secara rutin dan mandiri untuk meningkatkan kebutuhan tidur bayi yang berkualitas.   ABSTRACT Sleep is a human necessity that must be met, especially in the development phase because during sleep will occur the brain and body developments, so that sleep disturbance is a problem that would cause adverse effects on infants’ growth and development. The good quality of sleep can be created by providing the infants massage routinely. This study aimed to prove that the massage could affect the quality of sleep on the 0-3 months old baby. This study used Quasy-experimental design with One Group Pretest-Posttest. The sample 22 infants selected by total sampling technique observed on before and after the massage. The variables measured in this study are the quality of sleep. The results of study indicate that there is an effect of infant massage to the sleep quality on 0-3 months old babies (p value 0,008 < α = 0,05).Based on the results of this study it recommended for the families and communities to provide infant massage regularly and independently to increase the quality of sleep on the baby.  

Sources of the Scalp-Recorded Amplitude-Modulation Following Response

2002 ◽  
Vol 13 (04) ◽  
pp. 188-204 ◽  
Author(s):  
Shigeyuki Kuwada ◽  
Julia S. Anderson ◽  
Ranjan Batra ◽  
Douglas C. Fitzpatrick ◽  
Natacha Teissier ◽  
...  
Keyword(s):  
Animal Model ◽  
Amplitude Modulation ◽  
Single Unit ◽  
Modulation Frequency ◽  
Multiple Sources ◽  
High Modulation ◽  
Before And After ◽  
Single Unit Recordings ◽  
Composite Response ◽  
The Brain

The scalp-recorded amplitude-modulation following response (AMFR)” is gaining recognition as an objective audiometric tool, but little is known about the neural sources that underlie this potential. We hypothesized, based on our human studies and single-unit recordings in animals, that the scalp-recorded AMFR reflects the interaction of multiple sources. We tested this hypothesis using an animal model, the unanesthetized rabbit. We compared AMFRs recorded from the surface of the brain at different locations and before and after the administration of agents likely to enhance or suppress neural generators. We also recorded AMFRs locally at several stations along the auditory neuraxis. We conclude that the surface-recorded AMFR is indeed a composite response from multiple brain generators. Although the response at any modulation frequency can reflect the activity of more than one generator, the AMFRs to low and high modulation frequencies appear to reflect a strong contribution from cortical and subcortical sources, respectively.

scholarly journals Using Brain-Breaks® as a Technology Tool to Increase Attitude towards Physical Activity among Students in Singapore

2021 ◽  
Vol 11 (6) ◽  
pp. 784
Author(s):  
Govindasamy Balasekaran ◽  
Ahmad Arif Bin Ibrahim ◽  
Ng Yew Cheo ◽  
Phua Kia Wang ◽  
Garry Kuan ◽  
...  
Keyword(s):  
Physical Activity ◽  
Mixed Model ◽  
School Curriculum ◽  
Control Group ◽  
School Students ◽  
Mixed Model Analysis ◽  
Before And After ◽  
Brain Breaks ◽  
Student's Attitudes ◽  
The Brain

The purpose of this study was to investigate the effects of classroom-based Brain Breaks® Physical Activity Solution in Southeast Asia Singaporean primary school students and their attitude towards physical activity (PA) over a ten-week intervention. A total of 113 participants (8–11 years old) were randomly assigned to either an experimental (EG) or a control group (CG), with six classes to each group; the Brain Breaks® group (EG: six classes) and the Control group (CG: six classes). All EG members participated in a Brain Breaks® video intervention (three–five min) during academic classes and the CG continued their lessons as per normal. The student’s attitudes towards PA in both research conditions were evaluated using the self–reported Attitudes toward Physical Activity Scale (APAS), applied before and after intervention. The effects of the intervention on APAS scores were analysed using a mixed model analysis of variance with Time as within-subject and Group as between-subject factors. The analysis revealed evidence in support of the positive effect of classroom video interventions such as Brain Breaks® on student’s attitudes toward benefits, importance, learning, self-efficacy, fun, fitness, and trying to do their personal best in PA. The Brain Breaks® intervention provided a positive significant impact on students in Singapore. This study also revealed that interactive technology tools implemented into the school curriculum benefit students in terms of health and education.

Intraventricular injection of antibodies to β1-integrins generates pressure gradients in the brain favoring hydrocephalus development in rats

2009 ◽  
Vol 297 (5) ◽  
pp. R1312-R1321 ◽  
Author(s):  
Gurjit Nagra ◽  
Lena Koh ◽  
Isabelle Aubert ◽  
Minhui Kim ◽  
Miles Johnston
Keyword(s):  
Fluid Pressure ◽  
Active Role ◽  
Intraventricular Injection ◽  
Pressure Gradients ◽  
Tissue Pressure ◽  
Before And After ◽  
The Matrix ◽  
System 2 ◽  
Periventricular Area ◽  
The Brain

In some tissues, the injection of antibodies to the β1-integrins leads to a reduction in interstitial fluid pressure, indicating an active role for the extracellular matrix in tissue pressure regulation. If perturbations of the matrix occur in the periventricular area of the brain, a comparable lowering of interstitial pressures may induce transparenchymal pressure gradients favoring ventricular expansion. To examine this concept, we measured periventricular (parenchymal) and ventricular pressures with a servo-null micropipette system (2-μm tip) in adult Wistar rats before and after anti-integrin antibodies or IgG/IgM isotype controls were injected into a lateral ventricle. In a second group, the animals were kept for 2 wk after similar injections and after euthanization, the brains were removed and assessed for hydrocephalus. In experiments in which antibodies to β1-integrins ( n = 10) but not isotype control IgG/IgM ( n = 7) were injected, we observed a decline in periventricular pressures relative to the preinjection values. Under similar circumstances, ventricular pressures were elevated ( n = 10) and were significantly greater than those in the periventricular interstitium. We estimated ventricular to periventricular pressure gradients of up to 4.3 cmH2O. In the chronic preparations, we observed enlarged ventricles in many of the animals that received injections of anti-integrin antibodies (21 of 29 animals; 72%) but not in any animal receiving the isotype controls. We conclude that modulation/disruption of β1-integrin-matrix interactions in the brain generates pressure gradients favoring ventricular expansion, suggesting a novel mechanism for hydrocephalus development.

Study of electrical conductivity of biologically active points on the skin before and after mental activity

Vestnik ◽  
2021 ◽  
pp. 190-195
Author(s):  
М.С. Кулбаева ◽  
А.Н. Курал ◽  
Л.Б. Умбетьярова ◽  
Н.Т. Аблайханова ◽  
Г.К. Атанбаева ◽  
...  
Keyword(s):  
Physiological State ◽  
Mental Activity ◽  
The Body ◽  
Biologically Active ◽  
Mental Work ◽  
Heart Meridian ◽  
Before And After ◽  
Specific Organ ◽  
The Brain ◽  
Biologically Active Points

Человека давно интересует вопрос о том, как умственная нагрузка влияет на организм. Известно, что при длительной умственной работе преобразуется сила процессов возбуждения и торможения, изменяется соотношение между ними. С возникновением утомления в головном мозгу нарушаются взаимосвязи между корой больших полушарий и подкорковыми образованиями. При этом наблюдается снижение регулирующего влияния больших полушарий на все функции организма и уменьшение активизирующих воздействий подкорковых отделов мозга. Кроме того, длительное сидячие положение, состояние низкой двигательной активности ведут к значительному уменьшению центростремительных импульсов с рецепторов мышц, сухожилий, суставов. В исследовании приняли участие 17 относительно здоровые, имеющие стабильное физиологическое состояние девушек-студенток в возрасте от 21 до 25 лет. Для исследования были взяты 16 биологически активных точек на стандартных меридианах, связаных с определенным органом. Для оценки физиологического состояния органов до и после умственной нагрузки были исследованы показатели ЭП БАТ на коже. Выявлено снижение показателей каждого органа после умственной нагрузки по сравнению с показателями до ее выполнения со статистической достоверностью во всех исследуемых органах (р<0,05). Особенно низкие значения показателей ЭП БАТ после умственной нагрузки были выявлены в биоактивных точках меридиана печени F.3 Тай-Чун, меридиана толстой кишки GI.5 Ян-Си и GI.4 Хэ-Гу, меридиана сердца С.7 Шэнь-Мэнь, меридиана тонкой кишки IG.1 Шао-Цзе и IG.2 Цянь-Гу, меридиана почек R.1 Юн-Цюань и Р.2 Жань-Гу. Humans has long been interested in the question of how mental activity affects the body It is known that with prolonged mental work, the strength of the processes of excitation and inhibition is transformed, the ratio between them changes. With the onset of fatigue in the brain, the relationship between the cerebral cortex and subcortical formations is disrupted. At the same time, there is a decrease in the regulatory influence of the large hemispheres on all body functions and a decrease in the activating effects of the subcortical parts of the brain. In addition, prolonged sitting, a state of low motor activity leads to a significant decrease in centripetal impulses from the receptors of muscles, tendons, and joints. The study involved 17 relatively healthy, stable physiological condition of female students aged 21 to 25 years. For the study, 16 biologically active points were taken from standard meridians associated with a specific organ. To assess the physiological state of the organs before and after the load of mental labor, the indicators of EC BAP on the skin. A decrease in the indicators of each organ after mental labor was revealed in comparison with the indicators before mental labor with statistical reliability in all the studied organs (p˂0.05). Especially low values of the EC BAP values after a load of mental labor were found in the bioactive points of the liver meridian F. 3 Tai-Chun, the colon meridian GI.5 Yang-Si and GI. 4 He-Gu, the heart meridian C. 7 Shen-Men, the small intestine meridian IG.1 Shao-tse and IG.2 Qian-Gu, the meridian of the kidneys R. 1 Yun-Chuan and R. 2 Zhan-Gu.

scholarly journals Perfusion Imaging of the Brain Using Z-Score and Dynamic Images Obtained by Subtracting Images from before and after Contrast Injection

2004 ◽  
Vol 5 (3) ◽  
pp. 143 ◽  
Author(s):  
Sunseob Choi ◽  
Haiying Liu ◽  
Tae Beom Shin ◽  
Jin Hwa Lee ◽  
Seong Kuk Yoon ◽  
...  
Keyword(s):  
Perfusion Imaging ◽  
Z Score ◽  
Contrast Injection ◽  
Before And After ◽  
The Brain
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