Plankton

1962 ◽  
Vol 265 (1322) ◽  
pp. 335-341
Keyword(s):  
Surface Waters ◽  
Large Scale ◽  
Fish Meal ◽  
Water Masses ◽  
The Other ◽  
Small Scale ◽  
Local Areas ◽  
The Rich ◽  
The Many ◽  
European Markets

Today I must concentrate on just one of the many possible aspects of plankton research, one that 1 believe has a real future given the opportunity and the backing. This is: how the movement and mixing of water masses affect the plankton and, in turn, the effect this has on the other dependent communities and so on the fish themselves. We know that the mixing of different water masses produces conditions that are usually more productive than in either, and this can happen on a large scale, as in the convergences, or on a small scale in quite local areas. Sometimes the cause of the greater productivity is obvious—for example, off the coast of Peru where off-shore winds tend to drive away the depleted surface waters. These are replaced by the upwelling of nutrient-rich waters from below; some mixing takes place seeding the rich water with phytoplankton and resulting in one of the richest areas of production in the oceans and incidentally leading to an export of cheap fish meal that is having repercussions in the European markets.

scholarly journals Marine Rapid Environmental Assessment in the Gulf of Taranto: a multiscale approach

2016 ◽  
Vol 16 (12) ◽  
pp. 2623-2639 ◽  
Author(s):  
Nadia Pinardi ◽  
Vladyslav Lyubartsev ◽  
Nicola Cardellicchio ◽  
Claudio Caporale ◽  
Stefania Ciliberti ◽  
...  
Keyword(s):  
Surface Waters ◽  
Large Scale ◽  
Eastern Mediterranean ◽  
Small Scale ◽  
Multiscale Approach ◽  
Mesoscale Variability ◽  
Large Scale Circulation ◽  
Eddy Field ◽  
Multiscale Sampling ◽  
Circulation Structure

Abstract. A multiscale sampling experiment was carried out in the Gulf of Taranto (eastern Mediterranean) providing the first synoptic evidence of the large-scale circulation structure and associated mesoscale variability. The mapping of the mesoscale and large-scale geostrophic circulation showed the presence of an anticyclonic large-scale gyre occupying the central open ocean area of the Gulf of Taranto. On the periphery of the gyre upwelling is evident where surface waters are colder and saltier than at the center of the gyre. Over a 1-week period, the rim current of the gyre undergoes large changes which are interpreted as baroclinic–barotropic instabilities, generating small-scale cyclonic eddies in the periphery of the anticyclone. The eddies are generally small, one of which can be classified as a submesoscale eddy due to its size. This eddy field modulates the upwelling regime in the gyre periphery.

The Perks and Perils of Interdisciplinary Research

2018 ◽  
Vol 26 (S2) ◽  
pp. S55-S67 ◽  
Author(s):  
Erin Leahey
Keyword(s):  
Interdisciplinary Research ◽  
Large Scale ◽  
Policy Implications ◽  
The Other ◽  
Small Scale ◽  
Extra Time ◽  
Empirical Assessment ◽  
Cognitive Challenges

This paper synthesizes findings from two studies the author conducted that examine how engagement in interdisciplinary research (IDR) influences scholars’ careers. Results from these two studies, one large-scale and quantitative and the other small-scale and qualitative, provide a much needed empirical assessment of IDR’s effects on individual careers. In essence, they provide a nice antidote (and some caution) to the rhetoric and enthusiasm surrounding IDR. My co-authors of these studies and I find that engaging in interdisciplinary research increases a scholar’s visibility in terms of citations, but also presents challenges, including reduced productivity, cognitive challenges, lack of support, extra time and commitment, and framing of one’s work. This paper concludes by discussing the policy implications of this research.

scholarly journals Balanced reconnection intervals: four case studies

2008 ◽  
Vol 26 (12) ◽  
pp. 3897-3912 ◽  
Author(s):  
A. D. DeJong ◽  
A. J. Ridley ◽  
C. R. Clauer
Keyword(s):  
Case Studies ◽  
Large Scale ◽  
The Other ◽  
Small Scale ◽  
Polar Cap ◽  
Reconnection Rate ◽  
Magnetospheric Convection ◽  
The Third ◽  
New Name ◽  
Definition Of

Abstract. During steady magnetospheric convection (SMC) events the magnetosphere is active, yet there are no data signatures of a large scale reconfiguration, such as a substorm. While this definition has been used for years it fails to elucidate the true physics that is occurring within the magnetosphere, which is that the dayside merging rate and the nightside reconnection rate balance. Thus, it is suggested that these events be renamed Balanced Reconnection Intervals (BRIs). This paper investigates four diverse BRI events that support the idea that new name for these events is needed. The 3–4 February 1998 event falls well into the classic definition of an SMC set forth by Sergeev et al. (1996), while the other challenge some previous notions about SMCs. The 15 February 1998 event fails to end with a substorm expansion and concludes as the magnetospheric activity slowly quiets. The third event, 22–23 December 2000, begins with a slow build up of magnetospheric activity, thus there is no initiating substorm expansion. The last event, 17 February 1998, is more active (larger AE, AL and cross polar cap potential) than previously studied SMCs. It also has more small scale activity than the other events studied here.

scholarly journals Clusters of Galaxies

1980 ◽  
Vol 5 ◽  
pp. 699-714 ◽  
Author(s):  
Neta A. Bahcall
Keyword(s):  
Large Scale ◽  
Large Scale Structure ◽  
Scale Structure ◽  
Clusters Of Galaxies ◽  
Groups Of Galaxies ◽  
Formation And Evolution ◽  
The Rich ◽  
The Many ◽  
The Universe

AbstractClusters and groups of galaxies contain the majority of galaxies in the universe. The rich clusters, while less numerous than the many poor groups, are the densest and largest systems known, and can be easily recognized and studied even at relatively large distances. Their study is important for understanding the formation and evolution of clusters and galaxies, and for a determination of the large-scale structure in the universe.

A Method for Bonding PDMS Without Using Plasma

2010 ◽  
Author(s):  
Cristina Martin ◽  
Aarash Y. N. Sofla
Keyword(s):  
Hydrochloric Acid ◽  
Adhesion Strength ◽  
Glass Sample ◽  
Large Scale ◽  
The Other ◽  
Laboratory Research ◽  
Small Scale ◽  
Manufacturing Processes ◽  
Inexpensive Method ◽  
Chlorine Gas

The vapor-assisted treatment constitutes a simple and inexpensive method to increase the adhesion strength of polydimethylsiloxane and glass without using plasma. In this method, the targeted PDMS-glass sample is exposed to a vapor in an enclosed container for a certain time. Different chemicals were tested as possible vapor sources. No increase in the adhesion strength of PDMS-glass samples was observed when silanes without chloro functional groups were used. On the other hand, all alkyl trichlorosilanes tested in this study led to permanent bondings. In addition, an increase in the strength of the PDMS-glass adhesion was obtained with di- and monochlorosilanes as well as with hydrochloric acid solution. These results experimentally demonstrate that the hydrogen chlorine gas assists with the PDMS-glass bonding, making the vapor-assisted treatment a method with multiple applications in both small scale laboratory research and large scale manufacturing processes.

Mesoscale Spectra of Mars’s Atmosphere Derived from MGS TES Infrared Radiances

2007 ◽  
Vol 64 (5) ◽  
pp. 1717-1726 ◽  
Author(s):  
Takeshi Imamura ◽  
Yasuhiro Kawasaki ◽  
Tetsuya Fukuhara
Keyword(s):  
Seasonal Variation ◽  
Large Scale ◽  
Thermal Emission ◽  
The Other ◽  
Small Scale ◽  
High Latitudes ◽  
Mars Global Surveyor ◽  
Infrared Radiance ◽  
Infrared Radiances ◽  
Radiance Data

Abstract Wavenumber spectra of the atmospheric potential energy of Mars at mesoscales (wavelengths of 64–957 km) were obtained as a function of latitude, season, and Martian year using infrared radiance data obtained by the Thermal Emission Spectrometer (TES) onboard the Mars Global Surveyor (MGS) spacecraft. Spectral slopes tend to be flatter at smaller scales, and the slopes are usually flatter than −1 near small-scale ends. Near large-scale ends, the spectra sometimes show prominent steepening with slopes from −2 to −3. The power peaks in the high latitudes in winter and equinoxes, suggesting that eddies are generated preferentially in baroclinic zones. The seasonal variation at each latitude band, on the other hand, tends to be obscured by large interannual variability. An enhancement in the power was observed around the storm tracks in the Southern Hemisphere. Spectra of the terrestrial stratosphere were also obtained with a similar method from data taken by the Aura satellite and compared to the results for Mars.

scholarly journals Micro Disasters: The Case of Serial Killer Jeffrey Dahmer

2017 ◽  
Vol 7 (3) ◽  
pp. 444-452 ◽  
Author(s):  
Jeffrey M. Jentzen
Keyword(s):  
Heat Wave ◽  
Human Activity ◽  
Disaster Response ◽  
Large Scale ◽  
Crime Scene ◽  
The Other ◽  
Serial Killer ◽  
Small Scale ◽  
Community Or ◽  
Major Disaster

Disasters are commonly experienced as major devastating events that exceed the resources of an agency to respond, with effects emanating throughout a community or region. There are, however, those events that are more measured, more subtle, and with few actual deaths, which still distract investigators from their daily duties and routines and project long lasting and crippling effects to a community or nation. Disasters can occur from natural forces or be the result of human activity. Most forensic pathologists who practice over a significant time will encounter one or the other types of disaster, sometimes more than a few. In my own career, I have witnessed large-scale disasters, such as hundreds of deaths occurring as the result of a major heat wave, to small-scale disasters such as factory explosions or small airplane crashes at sea—each with their own challenges. In addition to the extent of the initial disaster, many require the detailed, exhaustive evidentiary recovery and examination of a crime scene. The Jeffrey Dahmer case, although only involving 11 actual victims, required a major disaster response, and continues to influence and affect a community over 25 years later.

Dependencies of Polychlorinated Biphenyl Concentrations Measured at the Great Lakes on Climate Variables

2020 ◽  
Author(s):  
Sandy Ubl ◽  
Martin Scheringer
Keyword(s):  
Wind Speed ◽  
Great Lakes ◽  
Wind Direction ◽  
Seasonal Cycle ◽  
Large Scale ◽  
Polychlorinated Biphenyl ◽  
The Other ◽  
Small Scale ◽  
Local Conditions ◽  
Pcb Congeners

<p>Polychlorinated biphenyls (PCBs) are persistent and hazardous chemicals that are still detected in the atmosphere and other environmental compartments although their production was banned several decades ago. At the Great Lakes region PCBs have been monitored via the IADN network since 1993. In this study, we report results from seven different PCB congeners measured at six different sites around the Great Lakes. The PCBs exhibit a strong seasonal cycle with highest concentrations in summer and lowest concentrations in winter. The concentrations measured in Chicago and Cleveland are higher compared to the concentrations reported from more remote stations. We evaluated the correlations for the seven PCB congeners at each station. PCB-53,-101,-118 and -138 are highly correlated at each of the six stations. PCB-180 is the least correlated with all the other PCBs. This is explicitly true for Eagle Harbor, where PCB-180 and -153 are not correlated with the other 6 PCBs. This may be explained by the less pronounced seasonal cycle of these heavier PCBs at Eagle Harbor. We observed significant correlations between PCB-28 concentrations at the remote stations, but PCB concentrations at the stations of Chicago and Cleveland are only poorly correlated with PCB concentrations at the other stations. The weak correlation of the PCB concentrations measured at the different stations and the relatively high concentrations of the PCB congeners at each station indicate that local conditions and small scale processes (sources, temperature, wind direction, wind speed) dictate the spatial distribution of the  PCBs. We will feed available data on temperature, wind speed, wind direction, emissions, precipitation, ice cover of the Great Lakes and large scale atmospheric teleconnection patterns into a General Additive Model (GAM) to further investigate the relationships between the measured PCB concentrations and selected environmental conditions and atmospheric parameters.<span> </span></p>

Cattle

1984 ◽  
Vol 8 ◽  
pp. 83-89
Author(s):  
Ian B. Howie
Keyword(s):  
Large Scale ◽  
Production Systems ◽  
Farming System ◽  
Small Scale ◽  
Market Forces ◽  
Poultry Production ◽  
Short Term ◽  
Fully Integrated ◽  
Beef Producers ◽  
The Many

Matching production to the markets for meat makes the assumption that individual producers can have an influence on market forces. This may well apply nowadays to some of the very large scale poultry production units but, individually, beef producers can have little if any influence on the marketing scene. Although there are farmers who produce several hundred fat cattle a year, the bulk of the beef produced comes from fairly small scale producers. Much of beef production is on a fairly haphazard basis with little or no recording or budgeting.Nevertheless, small scale producers and feeders who move in and out of the market can exploit local or short-term, favourable, market fluctuations and, with skilful buying and selling, make good profits on a quick turnover. Larger scale producers who have pre-planned fully integrated production systems cannot react as quickly to any great extent to short-term marketing opportunities. I regard marketing as only one of the many variable factors to be taken into account when planning a beef enterprise within a whole farming system, in which it is likely to be one of a number of enterprises which have to be kept in balance.

scholarly journals Numerical experiments on turbulent entrainment and mixing of scalars

2021 ◽  
Vol 927 ◽  
Author(s):  
A. Cimarelli ◽  
G. Boga
Keyword(s):  
Velocity Field ◽  
Numerical Experiments ◽  
Large Scale ◽  
Scalar Fields ◽  
Point Of View ◽  
Small Scale ◽  
Eddy Simulation ◽  
Turbulent Entrainment ◽  
Turbulence Closures ◽  
The Rich

Numerical experiments on the turbulent entrainment and mixing of scalars in a incompressible flow have been performed. These simulations are based on a scale decomposition of the velocity field, thus allowing the establishment from a dynamic point of view of the evolution of scalar fields under the separate action of large-scale coherent motions and small-scale fluctuations. The turbulent spectrum can be split into active and inactive flow structures. The large-scale engulfment phenomena actively prescribe the mixing velocity by amplifying inertial fluxes and by setting the area and the fluctuating geometry of the scalar interface. On the contrary, small-scale isotropic nibbling phenomena are essentially inactive in the mixing process. It is found that the inertial mechanisms initiate the process of entrainment at large scales to be finally processed by scalar diffusion at the molecular level. This last stage does not prescribe the amount of mixing but adapts itself to the conditions imposed by the coherent anisotropic motion at large scales. The present results may have strong repercussions for the theoretical approach to scalar mixing, as anticipated here by simple heuristic arguments which are shown able to reveal the rich dynamics of the process. Interesting repercussions are also envisaged for turbulence closures, in particular for large-eddy simulation approaches where only the large scales of the velocity field are resolved.

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