scholarly journals Different Seasonal Patterns in Song System Volume in Willow Tits and Great Tits

2016 ◽  
Vol 87 (4) ◽  
pp. 265-274
Author(s):  
Georgia K. Longmoor ◽  
C. Henrik Lange ◽  
Hannah Darvell ◽  
Lauren Walker ◽  
Seppo Rytkönen ◽  
...  
Keyword(s):  
Breeding Season ◽  
Seasonal Changes ◽  
Great Tit ◽  
Seasonal Patterns ◽  
Main Role ◽  
Blue Tit ◽  
Song System ◽  
Willow Tit ◽  
Area X

In most species of seasonally breeding songbirds studied to date, the brain areas that control singing (i.e. the song control system, SCS) are larger during the breeding season than at other times of the year. In the family of titmice and chickadees (Paridae), one species, the blue tit (Cyanistes caeruleus), shows the typical pattern of seasonal changes, while another species, the black-capped chickadee (Poecile atricapillus), shows, at best, very reduced seasonal changes in the SCS. To test whether this pattern holds up in the two Parid lineages to which these two species belong, and to rule out that the differences in seasonal patterns observed were due to differences in geography or laboratory, we compared the seasonal patterns in two song system nuclei volumes (HVC and Area X) in willow tits (Poecile montanus), closely related to black-capped chickadees, and in great tits (Parus major), more closely related to blue tits, from the same area around Oulu, Finland. Both species had larger gonads in spring than during the rest of the year. Great tit males had a larger HVC in spring than at other times of the year, but their Area X did not change in size. Willow tits showed no seasonal change in HVC or Area X size, despite having much larger gonads in spring than the great tits. Our findings suggest that the song system of willow tits and their relatives may be involved in learning and producing nonsong social vocalizations. Since these vocalizations are used year-round, there may be a year-round demand on the song system. The great tit and blue tit HVC may change seasonally because the demand is only placed on the song system during the breeding season, since they only produce learned vocalizations during this time. We suggest that changes were not observed in Area X because its main role is in song learning, and there is evidence that great tits do not learn new songs after their first year of life. Further study is required to determine whether our hypothesis about the role of the song system in the learned, nonsong vocalizations of the willow tit and chickadee is correct, and to test our hypothesis about the role of Area X in the great tit song system.

Phasic basal ganglia activity associated with high-gamma oscillation during sleep in a songbird

2012 ◽  
Vol 107 (1) ◽  
pp. 424-432 ◽  
Author(s):  
Shin Yanagihara ◽  
Neal A. Hessler
Keyword(s):  
Basal Ganglia ◽  
Phase Locking ◽  
Critical Role ◽  
Field Potential ◽  
Vocal Plasticity ◽  
Song System ◽  
Gamma Frequency ◽  
High Gamma ◽  
Area X

The basal ganglia is thought to be critical for motor control and learning in mammals. In specific basal ganglia regions, gamma frequency oscillations occur during various behavioral states, including sleeping periods. Given the critical role of sleep in regulating vocal plasticity of songbirds, we examined the presence of such oscillations in the basal ganglia. In the song system nucleus Area X, epochs of high-gamma frequency (80–160 Hz) oscillation of local field potential during sleep were associated with phasic increases of neural activity. While birds were awake, activity of the same neurons increased specifically when birds were singing. Furthermore, during sleep there was a clear tendency for phase locking of spikes to these oscillations. Such patterned activity in the sleeping songbird basal ganglia could play a role in off-line processing of song system motor networks.

Seasonal Patterns in Lipid Content of Lake Michigan Macroinvertebrates

1985 ◽  
Vol 42 (11) ◽  
pp. 1827-1832 ◽  
Author(s):  
Wayne S. Gardner ◽  
Thomas F. Nalepa ◽  
William A. Frez ◽  
Elizabeth A. Cichocki ◽  
Peter F. Landrum
Keyword(s):  
Lipid Content ◽  
Seasonal Changes ◽  
Loss Rate ◽  
Lake Michigan ◽  
Dry Weight ◽  
Seasonal Patterns ◽  
Organic Detritus ◽  
Mysis Relicta ◽  
Chironomid Larvae

Lipids in several taxa of macroinvertebrates from Lake Michigan were determined seasonally to help define the role of these animals in transferring energy in the lake. Ranges of mean lipid content relative to ash-free dry weight (AFDW) throughout the year were as follows: amphipods (Pontoporeia hoyi), 21–54%; lumbriculid oligochaetes (Stylodrilus heringianus), 12–19%; tubificid oligochaetes, 9–22%; chironomid larvae, 9–39%; and Mysis relicta, 26–37%. A pattern of increasing lipid content during spring was observed for P. hoyi, chironomids, and M. relicta, but seasonal changes were not apparent for oligochaetes. Excluding M. relicta, P. hoyi accounted for about 65% of the biomass and 70% of the energy contained in southern Lake Michigan benthic macroinvertebrates and may assimilate up to 30% of the total bioavailable organic detritus settling into the offshore hypolimnion. Calculation of the predation loss rate (production rate minus nonpredatory death rate) of P. hoyi indicated that about 13 000 cal∙m−2 (2.1 g AFDW∙m−2) of this amphipod may be consumed annually by fish and other predators in southern Lake Michigan.

Competition Between the Great Tit and the Blue Tit Outside the Breeding Season in Field Experiments

Ecology ◽  
1980 ◽  
Vol 61 (6) ◽  
pp. 1291-1296 ◽  
Author(s):  
Andre A. Dhondt ◽  
Roman Eyckerman
Keyword(s):  
Breeding Season ◽  
Field Experiments ◽  
Great Tit ◽  
Blue Tit

Role of spectrin in membrane fusion and in shape change of human erythrocyte ghost

1978 ◽  
Vol 36 (2) ◽  
pp. 328-329
Author(s):  
Hideo Hayashi ◽  
Yoshikazu Hirai ◽  
John T. Penniston
Keyword(s):  
Conformational Changes ◽  
Human Erythrocyte ◽  
Shape Change ◽  
Membrane Surface ◽  
Slight Modification ◽  
Active Role ◽  
Main Role ◽  
Bank Blood ◽  
Human Erythrocyte Ghost

Spectrin is a membrane associated protein most of which properties have been tentatively elucidated. A main role of the protein has been assumed to give a supporting structure to inside of the membrane. As reported previously, however, the isolated spectrin molecule underwent self assemble to form such as fibrous, meshwork, dispersed or aggregated arrangements depending upon the buffer suspended and was suggested to play an active role in the membrane conformational changes. In this study, the role of spectrin and actin was examined in terms of the molecular arrangements on the erythrocyte membrane surface with correlation to the functional states of the ghosts.Human erythrocyte ghosts were prepared from either freshly drawn or stocked bank blood by the method of Dodge et al with a slight modification as described before. Anti-spectrin antibody was raised against rabbit by injection of purified spectrin and partially purified.

Mesophyll conductance: the leaf corridors for photosynthesis

2020 ◽  
Vol 48 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Jorge Gago ◽  
Danilo M. Daloso ◽  
Marc Carriquí ◽  
Miquel Nadal ◽  
Melanie Morales ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Main Role ◽  
Mesophyll Conductance ◽  
Future Studies ◽  
Cell Structures ◽  
Leaf Tissues ◽  
Change Framework ◽  
Chloroplast Stroma

Besides stomata, the photosynthetic CO2 pathway also involves the transport of CO2 from the sub-stomatal air spaces inside to the carboxylation sites in the chloroplast stroma, where Rubisco is located. This pathway is far to be a simple and direct way, formed by series of consecutive barriers that the CO2 should cross to be finally assimilated in photosynthesis, known as the mesophyll conductance (gm). Therefore, the gm reflects the pathway through different air, water and biophysical barriers within the leaf tissues and cell structures. Currently, it is known that gm can impose the same level of limitation (or even higher depending of the conditions) to photosynthesis than the wider known stomata or biochemistry. In this mini-review, we are focused on each of the gm determinants to summarize the current knowledge on the mechanisms driving gm from anatomical to metabolic and biochemical perspectives. Special attention deserve the latest studies demonstrating the importance of the molecular mechanisms driving anatomical traits as cell wall and the chloroplast surface exposed to the mesophyll airspaces (Sc/S) that significantly constrain gm. However, even considering these recent discoveries, still is poorly understood the mechanisms about signaling pathways linking the environment a/biotic stressors with gm responses. Thus, considering the main role of gm as a major driver of the CO2 availability at the carboxylation sites, future studies into these aspects will help us to understand photosynthesis responses in a global change framework.

Sports Photography and Historical Development

2018 ◽  
Vol 5 (1) ◽  
pp. 93-115
Author(s):  
Miloš Stamenković
Keyword(s):  
Historical Development ◽  
Emotional Reaction ◽  
Main Role ◽  
Primary Role

SummarySports photography undoubtedly has a significant place in sports press and publicism. It’s main and primary role is to present sports to the readers as art, which it is. Sport is characterized by dynamic and varied movements, and the main role of sports photography is reflected in the fact that it is in this way that sport shows its essence. Having in mind that photography tells more than a thousand words it sends a clear message to the reader as well to people who are informed about events via sports portals. Sports photography is a multidimensional art for many reasons. When we say “multi”, it primarily refers to a wider range that sports photography has to offer, which means sports photography is not only directed at presenting athletes on the move and the main actors who contribute to achieving the results by their engagement – it also has the role of sports “psychophotography” which is an analysis and capture of the emotional reaction of an athlete after winning or losing from the opposing team.

Problems and prospects for the Russian banking supervision development in modern conditions

2020 ◽  
Vol 26 (6) ◽  
pp. 1283-1296
Author(s):  
K.A. Omarieva ◽  
P.G. Isaeva
Keyword(s):  
Banking System ◽  
Main Role ◽  
Banking Supervision ◽  
Monetary System ◽  
The Russian Federation ◽  
Document Flow ◽  
Development Methods ◽  
Further Development ◽  
Development Prospects

Subject. The article addresses problems and prospects for the banking supervision development in the Russian Federation under modern conditions. Objectives. We review the essence and methods of organization of the banking supervision, and identify the main problems and prospects for its development. Methods. To provide valid, reliable and reasoned recommendations, we apply normative and integrated approaches to the study of the banking supervision effectiveness in the current circumstances. Results. The paper investigates main problems and development prospects for the Russian banking supervision. The essential importance of supervision comes from the main role of the banking system in maintaining accounts of economic entities and making settlements. Even minor failures or delays in operations can lead to negative outcomes and disastrous consequences for the entire monetary system and the national economy. Therefore, we highlight issues that require attention, and make proposals for further development of the banking supervision. Conclusions. In the context of dynamically developing economy, the banking practice is becoming more complex. As a result, there is a need for new financial instruments that can reduce risks, increase the speed and efficiency of operations and document flow, and help achieve the world levels of introduced standards.

Biological Role of CDK 11 and 12 in Cell Cycle and its Function in Tumorigenesis

2020 ◽  
Author(s):  
Shamim Mushtaq
Keyword(s):  
Breast Cancer ◽  
Cell Cycle ◽  
Web Of Science ◽  
The Body ◽  
Main Role ◽  
Hallmarks Of Cancer ◽  
Cyclin Dependent Kinases ◽  
Tumor Studies ◽  
Cycle Regulation

Uninhibited proliferation and abnormal cell cycle regulation are the hallmarks of cancer. The main role of cyclin dependent kinases is to regulate the cell cycle and cell proliferation. These protein kinases are frequently down regulated or up regulated in various cancers. Two CDK family members, CDK 11 and 12, have contradicting views about their roles in different cancers. For example, one study suggests that the CDK 11 isoforms, p58, inhibits growth of breast cancer whereas, the CDK 11 isoform, p110, is highly expressed in breast tumor. Studies regarding CDK 12 show variation of opinion towards different parts of the body, however there is a consensus that upregulation of cdk12 increases the risk of breast cancer. Hence, CDK 11 and CDK 12 need to be analyzed to confirm their mechanism and their role regarding therapeutics, prognostic value, and ethnicity in cancer. This article gives an outline on both CDKs of information known up to date from Medline, PubMed, Google Scholar and Web of Science search engines, which were explored and thirty relevant researches were finalized.

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