Influence of the physiological condition of bivalve recruits on their post-settlement dispersal potential

2020 ◽  
Vol 636 ◽  
pp. 77-89 ◽  
Author(s):  
M Forêt ◽  
F Olivier ◽  
P Miner ◽  
G Winkler ◽  
JB Nadalini ◽  
...  
Keyword(s):  
Migration Behavior ◽  
Energy Reserves ◽  
Substrate Selection ◽  
Behavioral Differences ◽  
Fall Velocity ◽  
Physiological Profile ◽  
Secondary Dispersal ◽  
Fine Sediments ◽  
Chaetoceros Gracilis ◽  
Dispersal Potential

Secondary dispersal (= migration) of bivalves occurs after metamorphosis and is a key recruitment process that can radically change patterns of primary settlement. An example of secondary dispersal is active migration behavior of bivalve recruits such as in bysso-pelagic drift. We hypothesize that these active migrations represent an energy cost for recruits and that the ability to actively migrate will depend upon the recruit’s physiological profile (quantity and quality of energy reserves). In lab experiments, we hatched 4 batches of recruits of Venus verrucosa with different physiological profiles by varying rearing temperature and diet composition. We then introduced these recruits into a fall velocity tube (5 m height) to estimate their vertical fall velocity as a proxy of their dispersal potential: slower fall velocity implies enhanced dispersal potential. We also compared alive vs. passive (dead) recruits to assess behavioral differences. Fall velocity increased logarithmically with recruit volume for each treatment, and no differences between active and passive individuals were observed for batches reared at 20°C with a mixture of Tisochrysis lutea and Chaetoceros gracilis. By contrast, active recruits in 2 other treatments (T. lutea at 20°C and a mix of C. gracilis and T. lutea at 15°C) significantly decreased their fall velocity regardless of their volume. Moreover, the ability of recruits to control their fall velocity by their behavior was correlated with triglyceride content. Recruits with the highest energy reserves had the greatest capacity to decrease their fall velocity, which suggests a major role of physiological conditions on potential secondary dispersal. We also used a benthic flume to test the substrate selection ability of recruits depending on their physiological profile and found no differences between physiologically different batches. However, V. verrucosa recruits preferred fine sediments, unlike adults, which live mainly in coarse sediment habitats; such difference in substrate preference suggests potential secondary migrations between nursery and adult areas.

Extraversion and Dopamine

1998 ◽  
Vol 3 (1) ◽  
pp. 37-50 ◽  
Author(s):  
Thomas H. Rammsayer
Keyword(s):  
Individual Differences ◽  
D2 Receptor ◽  
D2 Receptors ◽  
Behavioral Differences ◽  
Biological Mechanisms ◽  
Brain Dopamine ◽  
Personality Dimension ◽  
Time Performance ◽  
Reaction Time Performance ◽  
Induced Changes

Recent research suggests that individual differences in brain dopamine (DA) functioning may be related to the personality dimension of extraversion. The present study was designed to further elucidate the biological mechanisms underlying behavioral differences between extraverts and introverts. For this purpose, the differential effects of a pharmacologically induced blockade of mesolimbocortical DA D2 receptors on reaction-time performance were investigated in 24 introverted and 24 extraverted subjects. Introverts were found to be much more susceptible to pharmacologically induced changes in D2 receptor activity than extraverts. This finding provides additional experimental evidence for the notion that individual differences in D2 receptor responsivity may represent a neurobiological substratum for the personality dimension of extraversion.

Race on Both Sides of the Razor

2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Terence D. Keel
Keyword(s):  
Social Constructionism ◽  
Political Correctness ◽  
Genetic Basis ◽  
Genetic Research ◽  
Scientific Progress ◽  
Social Constructionist ◽  
Behavioral Differences ◽  
Social Activists ◽  
Continued Use ◽  
Biological Differences

The proliferation of studies declaring that there is a genetic basis to health disparities and behavioral differences across the so-called races has encouraged the opponents of social constructionism to assert a victory for scientific progress over political correctness. I am not concerned in this essay with providing a response to critics who believe races are expressions of innate genetic or biological differences. Instead, I am interested in how genetic research on human differences has divided social constructionists over whether the race concept in science can be used for social justice and redressing embodied forms of discrimination. On one side, there is the position that race is an inherently flawed concept and that its continued use by scientists, medical professionals, and even social activists keeps alive the notion that it has a biological basis. On the other side of this debate are those who maintain a social constructionist position yet argue that not all instances of race in science stem from discriminatory politics or the desire to prove that humans belong to discrete biological units that can then be classified as superior or inferior. I would like to shift this debate away from the question of whether race is real and move instead toward thinking about the intellectual commitments necessary for science to expose past legacies of discrimination.

Humus state of chernozem at different ways of tillage in the agrosystems of the left-bank forest steppe of Ukraine

2015 ◽  
Vol 2 (3) ◽  
pp. 61-77
Author(s):  
O. Demydenko ◽  
V. Velychko
Keyword(s):  
Soil Cover ◽  
Forest Steppe ◽  
Left Bank ◽  
Energy Reserves ◽  
Soil Resources ◽  
Global Soil ◽  
Humus Accumulation ◽  
By Products ◽  
The Way

The contemporary condition of soil cover in Ukraine is characterized. The attention is focused onto widespread degradation processes in soils. The causes that determine the development of these negative processes are considered. The contemporary informational support for the condition of soil cover in Ukraine is estimated. In general, the current available information is of narrow-departmental nature, obtained by different methods and non-correlated monitoring programs. As a rule, it is stored in under-structured databases, incompatible with other information systems; mainly recorded on paper media unusable with modern technologies, whereby such information resources are diffi cult to be compiled together. These disadvantages are strong constraints against consistent usage of materials for evaluation, forecast and management of changes in the soil cover. The Soil Observation program should thereby be combined with Agrochemical Passportization and ecology-ameliora- tive monitoring; in other words, the application of innovative soil-agrochemical methodology is considered. Each individual type of surveys shall complement the others, and taken altogether, they shall constitute a con- sistent Information System, capable of solving the problems of assessing the condition, forecasting, manage- ment, usage and protection of soil resources. The monitoring procedures should be conducted on the basis of a new soil concept in line with unifi ed programs and methods, so as to meet European approaches to the maxi- mum extent. Such a technical composition enables getting information on present-day processes in soils, and is the only combination that actually helps us to “ecologize” our knowledge of soils, which is the leading trend in the scope of global soil-science. Thus obtained results will serve as a State-owned tool which would subse- quently facilitate the use and protection of soil resources all over the country, to be involved in a united global soil-information scope. The attention is focused onto social signifi cance of the information on soils and their fertility in terms of land resources optimization, as well as the formation of sustainable land use in Ukraine. Aim. To demonstrate the long-term effect of different ways of tillage of typical low-humus chernozem on the change in humus content and composition and the direction of transformation processes of organic fertili- zers. To study the changes in the structure of energy reserves in group and fractional composition of humus in typical low-humus light-loamy chernozem of the Forest-Steppe of Ukraine. Methods. Field, laboratory, microbiological, computational, mathematical and statistical. Results. It was determined that in conditions of long-term subsurface tillage the most effi cient humus accumulation occurs in the 0–20 cm layer of chernozem with simultaneous increase in its content in the lower part of the processed layer without any accumulation differentiation. Surface tillage leads to expressed differentiation in humus accumulation in the 0–20 cm layer of soil (0.005 % per year). When 6 t/ha of humus are replaced by 7 t/ha of by-products the intensity of humus accumulation is decreasing regardless of the way of tillage, but humus accumulation was found to be the most effi cient for subsurface tillage. The application of subsurface tillage leads to the increase in the ratio of C HA : C FA , which is conditioned by the increase in the humifi cation of plant remains of by-products in the 0−20 cm layer of soil by 110–112 % – for subsurface tillage, and by 105 % – for surface tillage. Conclusions. It was established that systematic subsurface tillage of typical chernozem of the Left-Bank Forest-Steppe of Ukraine leads to the structuring both of the total reserves of energy С org , and its quality content, aimed at the increase in the intensity of the processes of humifi cation and accumulation of organic carbon, and the decrease in miner- alization. The ratio of energy reserves С org of humic acids to fulvic acids in the 0−30 cm layer of chernozem is 1.85−1.87 regardless of the way of tillage, which testifi es to the repeatability of humus accumulation, but the total reserves of energy С org was higher for subsurface tillage (+ 31 Teracalorie/ha) compared to deep plough- ing. As for the surface tillage, the energy enrichment was at the level of deep ploughing.

Fertilization System as a Factor of Transforming the Humus State of the Soil

2015 ◽  
Vol 2 (2) ◽  
pp. 39-44
Author(s):  
V. Lopushniak
Keyword(s):  
Crop Rotation ◽  
Podzolic Soil ◽  
Humus Content ◽  
Organic Fertilizers ◽  
Mineral Fertilizers ◽  
Forest Steppe ◽  
Content Increase ◽  
Energy Reserves ◽  
Gross Energy ◽  
Stable Forms

Aim. To establish the effect of different fertilization systems in short fi eld crop rotation on the change in the state of humus in the dark gray podzolic soils in Western Forest-Steppe of Ukraine. Methods. Field studies were carried out in a stationary experiment of the Department of Soil Science and Agricultural Chemistry of the L’viv National Agrarian University; determination of humus content – according to DSTU 4289:2004, and that of its labile forms – in accordance with DSTU 4732:2007, fraction-group composition – by Ponomare- va-Plotnikova’s method, according to the measurement procedure 31-497058-008-2002. Results. The use of organo-mineral fertilizer system in short fi eld crop rotation with the saturation of organic fertilizers of 15 t/ha of crop rotation contributes to the humus content increase by 0.7 % after the third rotation in 0–40 cm layer of dark gray podzolic soil, the increase in the share of stable forms of humic compounds up to 57–59 % and the increase in the ratio of R HA :R FA to 1.3–1.4. The study demonstrated very high dependence of amount of gross energy reserves in the humus on the R HA :R FA ratio. Conclusions. The combined application of organic fertili- zers in the form of manure, non-market of the crop (straw) and siderate, along with mineral fertilizers is re- commended in short fi eld crop rotations of Western Forest-Steppe of Ukraine toensure expanded reproduction of fertility of dark gray podzolic soil, improvement of its humus status, increase in gross energy reserves and the share of the stable forms and humic acids in the humus.

Anthropometrical and Physiological Profile of Chinese Elite Sport Climbers

2011 ◽  
Vol 15 (1) ◽  
pp. 23-29 ◽  
Author(s):  
Wilson W. Cheung ◽  
Tom K. Tong ◽  
Audry B. Morrison ◽  
Raymond W. Leung ◽  
Yuk-Luen Kwok ◽  
...  
Keyword(s):  
Elite Sport ◽  
Physiological Profile

Two Representations of the Moscow Art Theater Audience

2020 ◽  
Vol 17 (5) ◽  
pp. 462-476
Author(s):  
Alexander A. Ushkarev ◽  
Galina G. Gedovius ◽  
Tatyana V. Petrushina
Keyword(s):  
Online Community ◽  
Modern Art ◽  
Virtual Space ◽  
Demographic Parameters ◽  
Cultural Consumption ◽  
Cultural Activity ◽  
Behavioral Differences ◽  
Technological Revolution ◽  
Definition Of

The technological revolution of recent decades has already brought art to the broadest masses, and the unexpected intervention of the pandemic has significantly accelerated the process of migration of theatrical art to the virtual space, causing the corresponding dynamics of the audience. What is the theater audience in the era of digitalization and the spread of alternative forms of cultural consumption? How does the theater build its relationship with the audience today? In search of answers, we conducted a series of sociological surveys of the Chekhov Moscow Art Theater’s audience — both at the theater’s performances and in the online community of its fans. The purpose of this phase of the study was to answer the fundamental questions: do spectators surveyed in the theater and those surveyed online represent the same audience; what are their main differences; and what are the drivers of their spectator behavior? The article presents the main results of a comparative analysis of two images of the Moscow Art Theatre’s audience based on a number of content parameters by two types of surveys, as well as the results of a regression analysis of the theater attendance. The study resulted in definition of the qualitative and behavioral differences between the theater visitors and the viewers surveyed online, and identification of the factors of theater attendance for both of the represented audience groups. The study made it possible to clarify the role of age and other socio-demographic parameters in cultural activity, as well as the influence of preferred forms of cultural consumption (live contacts or online views) on one’s attitude to art, motivation and spectator behavior. The conclusions of the study, despite the uniqueness of the object, reflect the general patterns of the modern art audience’s dynamics.

FEATURES OF MONITORING OF DEGRADED LANDS TO ASSESS POSSIBILITIES FOR THEIR REHABILITATION

2020 ◽  
pp. 37-43
Author(s):  
B.I. KORZHENEVSKIY ◽  
◽  
N.V. KOLOMIYTSEV ◽  
G.YU. TOLKACHEV
Keyword(s):  
Agricultural Land ◽  
Meteorological Data ◽  
Morphological Characteristics ◽  
Energy Reserves ◽  
Land Restoration ◽  
Degraded Land ◽  
Degraded Lands ◽  
The Past ◽  
Unused Land ◽  
Restoration Work

Putting out of using large areas of agricultural lands in the central region over the past years has led to worsening the prospects of their purposed use, although the problem of the relevance of their restoration still remains. For many years the unused land was exposed to both natural exogenous processes such as erosion, suffusion, etc. and biological and chemical changes, usually for the worse for agriculture. There are considered elements of monitoring aimed at assessing the prospects or lack of perspectives of rehabilitation of degraded lands. An energy approach to assessing the state of slopes and soils located within these slopes is presented. The main factors of natural and anthropogenic character in assessing the prospects for land restoration are their steepness, excess relative to local bases of erosion other morphological characteristics of slopes which in general is reduced to an assessment of the energy provision of slopes and soils. So the higher the energy capacity of slopes – they are less promising for development, for soils – there is a reverse picture – the higher their energy reserves, the more promising is their use. Approaches to zoning the territory for monitoring from larger taxons of natural and anthropogenic genesis to the sites of special surveillance within which the prospects for rehabilitation of the agricultural land are evaluated. The most important factor is the material expediency of such actions, i.e. before starting the restoration work it is necessary to assess the profitability or loss of the proposed event. In cases of the material expediency it is feasible as further actions to include energy assessments of slopes and soils; zoning of the object according to the steepness and oriented characteristics of soil washout; and the possibility of obtaining agronomic and meteorological data on a timely basis. The result of the work is a forecast assessment of the prospects for restoring degraded land for the intended purpose using modern databases and WEB-systems.

Profiles of Autonomic Activity in Autism Spectrum Disorder with and without Anxiety

2019 ◽  
Author(s):  
Valentina Parma ◽  
Nicola Cellini ◽  
Lisa Guy ◽  
Alana McVey ◽  
Keiran Rump ◽  
...  
Keyword(s):  
Autism Spectrum Disorder ◽  
Anxiety Disorders ◽  
Physiological Activity ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Parasympathetic Activity ◽  
Typically Developing ◽  
Physiological Profile ◽  
School Aged Children ◽  
Advance Research

Objective: Anxiety disorders are common among youth with autism spectrum disorder (ASD). Both anxiety and ASD are associated with differences in physiological activity. To date, few studies have investigated the physiological profile of youth with ASD and even fewer have systematically assessed how the co-occurrence of anxiety disorders and ASD modulates resting physiological activity.Method: The aim of the present study was to evaluate sympathetic and parasympathetic activity at rest in 75 school-aged children and adolescents with ASD, with (ASD+Anxiety = 22, 6F) and without co-occurring anxiety (ASD Alone =15, 6F) and to compare their physiological profile with that of matched typically developing controls (TDC) with (Anxiety Alone = 16, 6F) and without co-occurring anxiety disorders (TDC = 22, 8F).Results: Results indicated reduced sympathetic and parasympathetic activity at rest in ASD as compared to TDC youth without anxiety. The ASD+Anxiety and Anxiety Alone groups showed different sympathetic, but similar parasympathetic, activity. Correlational, multivariate, and regression analyses indicated that the four groups differed among several physiological and subjective measures.Conclusion: These findings suggest that ASD and anxiety are associated with distinct profiles of autonomic nervous system activity that cannot be reduced to either the sympathetic or parasympathetic branch alone. An autonomic profile-based approach is more likely to advance research, diagnosis, and treatment of ASD and anxiety than unidimensional, single-modality approaches.

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