scholarly journals Intertidal fishes of Mauritius with special reference to shallow tidepools

2019 ◽  
Vol 7 ◽  
Author(s):  
Erik Arndt ◽  
Ronald Fricke
Keyword(s):  
Species Number ◽  
Resident Species ◽  
High Coverage ◽  
Tropical Regions ◽  
Large Numbers ◽  
Context Data ◽  
Intertidal Habitats ◽  
Different Sources ◽  
Made In ◽  
Intertidal Fishes

Intertidal fishes are found in large numbers and play an important role in their ecosystems, but knowledge of their ecology is still very limited in many tropical regions. Within this context, data from intertidal fishes in Mauritius were compiled from different sources and intertidal resident species were examined in Mauritian tidepools. A total of 292 fish species occurring in Mauritius were reported from intertidal habitats, of which 62 species represent permanent intertidal residents. The species number in the studied pools increased, not only with the proportion of stones and rock covering the pool bottom, but also with pool facilities, for example, the supply of boulders and a high coverage of macro-algae. All examined pools were dominated by two species, Bathygobius coalitus and Istiblennius edentulus. Their abundance increased with decreasing pool size, peaking in pools with a surface area between 1-2 m2 during the lowest level of ebb tide. This 'overcrowding effect' may be linked to the absence of predators in these very small pools. The comparison of present data with results of a survey made in the same area in 1995 suggested a decrease of resident species occurred during the last decades, probably linked to human influences, such as eutrophication and water pollution.

Microanalysis of precipitates in a ferritic steel

1978 ◽  
Vol 36 (1) ◽  
pp. 618-619
Author(s):  
J.M. Titchmarsh
Keyword(s):  
Ferritic Steel ◽  
Particle Identification ◽  
Energy Dispersive ◽  
Objective Lens ◽  
Ferritic Steels ◽  
Replica Technique ◽  
X Ray ◽  
Large Numbers ◽  
Scanning Transmission ◽  
Made In

The advances in recent years in the microanalytical capabilities of conventional TEM's fitted with probe forming lenses allow much more detailed investigations to be made of the microstructures of complex alloys, such as ferritic steels, than have been possible previously. In particular, the identification of individual precipitate particles with dimensions of a few tens of nanometers in alloys containing high densities of several chemically and crystallographically different precipitate types is feasible. The aim of the investigation described in this paper was to establish a method which allowed individual particle identification to be made in a few seconds so that large numbers of particles could be examined in a few hours.A Philips EM400 microscope, fitted with the scanning transmission (STEM) objective lens pole-pieces and an EDAX energy dispersive X-ray analyser, was used at 120 kV with a thermal W hairpin filament. The precipitates examined were extracted using a standard C replica technique from specimens of a 2¼Cr-lMo ferritic steel in a quenched and tempered condition.

The growth of the pollen tube wall in Oenothera organensis

1975 ◽  
Vol 18 (3) ◽  
pp. 519-532
Author(s):  
H.G. Dickinson ◽  
J. Lawson
Keyword(s):  
Pollen Tube ◽  
Tube Wall ◽  
Wall Material ◽  
Fibrillar Material ◽  
Stage Of Development ◽  
Large Numbers ◽  
Membrane Bound ◽  
Pollen Tube Wall ◽  
Different Sources ◽  
Dictyosome Vesicles

The growth of the pollen tube wall of Oenothera is effected by the expulsion of fibrillar material from the cytoplasm into the developing wall. This material may also be seen in the cytoplasm, contained in membrane-bound vesicles. It is not clear how the content of the vesicles is discharged, but it appears not to involve the participation of microtubules. The source of the cytoplasmic fibrillar bodies depends upon the stage of development of the pollen tube. The earilest growth is derived from the inclusion into the wall of vesicles containing pre-formed materials present in the grain on pollination. During the next stage of growth the wall is derived from the content of double-membraned inclusions also present in the pollen. The content of the former vesicles is not so similar to the wall as the latter, but intermediates between the 2 types of vesicle may be seen in the cytoplasm, indicating that the former are formed from the latter. Most of the tube wall is derived from the products of dictyosomes in the pollen grain or tube. These dicytosomes are few in number and they must be exceedingly active. This, and the observation that dictyosome vesicles are frequently associated with banked complexes of mitochondria, indicates that some steps in the metabolism of the vesicular content, perhaps phosphorylation, take place distant from the dicytosomes. These different sources of fibrillar material presumably permit the rapid starting of tube growth, without any attendant metabolism. However, it would be impossible to include enough pre-formed wall material in the grain to enable the full growth of the tube, so once started, it seems that the tube then relies on the elaboration of simple reserves for the contruction of its wall. These reserves are likely to be held in the pollen, and may be the large numbers of starch grains characteristic of the pollen cytoplasm.

scholarly journals Regional and Seasonal Differences in Species Composition and Trophic Groups for Tidepool Fishes of a Western Pacific Island – Taiwan

2018 ◽  
Vol 23 (1) ◽  
pp. 1 ◽  
Author(s):  
Colin K. C. Wen ◽  
Li-Shu Chen ◽  
Kwang-Tsao Shao
Keyword(s):  
Species Composition ◽  
Fish Species ◽  
Fish Assemblages ◽  
Coastal Development ◽  
Species Number ◽  
Pacific Region ◽  
Trophic Groups ◽  
Species Numbers ◽  
Intertidal Fish ◽  
Intertidal Fishes

Spatial and temporal variations in the species composition of assemblages are common in many marine organisms, including fishes. Variations in the fish species composition of subtidal coral reefs have been well documented, however much less is known about such differences for intertidal fish assemblages. This is surprising, given that intertidal fishes are more vulnerable to terrestrial human disturbances. It is critical to evaluate the ecology and biology of intertidal fishes before they are severely impacted by coastal development, especially in developing countries such as those in the tropical western Pacific region where coastal development is rapidly increasing. In this study, we investigated the species composition, abundance, biomass and species number (richness) for intertidal fish assemblages in subtropical (northern) and tropical (southern) Taiwan across four seasons by collecting fishes from tidepools using clove oil. We also examined the gut contents of collected fishes to identify their trophic functional groups in order to investigate regional and seasonal variations for different trophic groups. We found significant differences in the species composition of tidepool fish assemblages between subtropical and tropical Taiwan. Bathygobius fuscus, Abudefduf vaigiensis and Istiblennius dussumieri were dominant species in subtropical Taiwan, whereas Bathygobius coalitus, Abudefduf septemfasciatus and Istiblennius lineatus were dominant in tropical Taiwan. Other species such as Bathygobius cocosensis, Abudefduf sordidus and Istiblennius edentulus were common in both regions. For trophic groups, omnivores and detritivores had or showed trends towards higher species numbers and abundances in the subtropical region, whereas herbivores, planktivores and general carnivores had or showed trends towards higher species numbers and biomass in the tropical region. Overall, many intertidal fish species and trophic groups showed differences in abundance, biomass and species number between subtropical and tropical Taiwan. Further studies on large scale geographical gradients in trophic groups and species compositions in the Indo-west Pacific region are encouraged to assist with ecosystem monitoring and assessment. Keywords: Intertidal fishes, spatio-temporal pattern, feeding guild, diet

Defining Relationship Marketing: A review of Research

2007 ◽  
Vol 3 (2) ◽  
pp. 64-76 ◽  
Author(s):  
C. Madhavaiah ◽  
S. Durga Rao
Keyword(s):  
Content Analysis ◽  
Relationship Marketing ◽  
Customer Loyalty ◽  
Previous Literature ◽  
The Core ◽  
Analysis Methodology ◽  
Different Sources ◽  
Made In

The term “relationship marketing” has become a popular concept among the practitioners of marketing as well as academics during the last several years. It is very beneficial to firms because it can foster customer loyalty and re-patronage behaviour. Apart from its growing popularity among academia and practitioners, still there exists no consensus on the basic “constructs” of relationship marketing. Different authors have different opinions about what should and what should not be at the core of what constitutes “relationship marketing”. In view of this, an attempt is made in this paper to collect and analyse 36 definitions of relationship marketing from different sources of previous literature. Content analysis methodology has been used to identify the underlying “constructs” in each of the 36 definitions. The results suggest that there are seven RM “constructs” which constitute the major conceptualisations of relationship marketing. Out of 36 definitions of relationship marketing, only one definition is judged as being more comprehensive and generally acceptable and a new definition for relationship marketing is presented as an inducement to further research and discussion.

scholarly journals Closing up onto our sun: solar imaging

2020 ◽  
Vol 240 ◽  
pp. 07011
Author(s):  
Kushagra Shrivastava ◽  
Keith Wen Kai Chia ◽  
Kang Jun Wong ◽  
Alfred Yong Liang Tan ◽  
Hwee Tiang Ning
Keyword(s):  
Solar Activity ◽  
The Sun ◽  
Research Needs ◽  
Large Numbers ◽  
Wide Range ◽  
Future Science ◽  
Insight Into ◽  
Term Data ◽  
Made In

Solar activity research provides insight into the Sun’s past, future (Science Daily, 2018). The solar activity includes observations of large numbers of intense sunspots, flares, and other phenomena; and demands a wide range of techniques and measurements on the observations. This research needs long term data collection before critical analyses can occur, to generate meaningful learning and knowledge. In this project, we will use solar imaging to make observations of solar activity, and take our baby steps to make contributions in citizen science. Observations will be made in 3 wavelengths to gain a more thorough analysis by looking at different perspectives of the Sun, namely H-Alpha, Calcium-K, and white light.

Archaeology in New China

Antiquity ◽  
1963 ◽  
Vol 37 (147) ◽  
pp. 176-184 ◽  
Author(s):  
Hsia Nai
Keyword(s):  
Field Work ◽  
Archaeological Research ◽  
Historical Science ◽  
Considerable Success ◽  
Large Numbers ◽  
History Of ◽  
Ancient Monuments ◽  
Economic Construction ◽  
Abundant Data ◽  
Made In

Archaeology as a branch of historical science has made new headway in the thirteen years since the founding of the Chinese People's Republic. The scale of its work has expanded and methods of research have been improved. Large numbers of young archaeological workers have been trained. In the course of the nation's gigantic economic construction, remains of ancient settlements and tombs have been uncovered in many places, yielding numerous important relics which have provided abundant data for archaeological research. Throughout the country, hosts of archaeological workers from research institutes, universities, museums and institutions for the preservation of ancient monuments are carrying out both field work and academic study and have already attained considerable success in their efforts to explore the history of ancient China on the basis of archaeological finds. All this has given further impetus to the advance of Chinese archaeology.Archaeological finds made in New China are so rich that the present article can attempt to discuss only some of the most important problems.

Biodiversity and Impacts of Climate Change in Home Gardens

2022 ◽  
pp. 1432-1453
Author(s):  
Sebak Kumar Jana ◽  
Joyashree Roy
Keyword(s):  
Climate Change ◽  
Land Use ◽  
Home Gardens ◽  
Home Garden ◽  
Tropical Regions ◽  
Key Characteristics ◽  
Dry Zone ◽  
Depth Study ◽  
Climate Shocks ◽  
Made In

Home garden is a complex multi-functional land use system that combines multiple farming components of the homestead and provides environmental services, household needs, and employment and income generation opportunities to the households. Predicted climate changes have serious implications for crop and livestock yields particularly in tropical regions. Home garden may act as a cushion to the adverse climate shocks. There is dearth of in-depth study of home garden ecosystem in India. The authors have selected 100 households in Garhbeta-1 block, which is in the dry zone in the district of Paschim Medinipur in West Bengal, India for the study. The main objectives of the chapter include (1) identification of the key characteristics of the home garden, (2) assessing biodiversity in home gardens, (3) identifying the pattern of climate change from the household perceptions and the problems in home garden, and (4) the changes made in the home gardens.

Further Observations on the Incidence of Parasitism of Flea Beetles by the Nematode, Howardula phyllotretae.

1935 ◽  
Vol 13 (3) ◽  
pp. 163-166
Author(s):  
J. N. Oldham
Keyword(s):  
Entire Period ◽  
Flea Beetles ◽  
Active Life ◽  
Large Numbers ◽  
Made In

During a study of the nematode, Howardula phyllotretae Oldham, 1933, parasitic in Flea Beetles of the genus Phyllotreta, records were kept in order to get data concerning the incidence of infection. The records already published, with a description of the parasite (Oldham, 1933), refer solely to the observations made during 1931. During the two subsequent years large numbers of beetles belonging to the following species: P. atra, P. cruciferae, P. nigripes, P. undulata and P. vittula, were collected and examined for parasites. Collections were made, in each year, from about the beginning of April, when the adults started to emerge from their winter shelters, up to the end of September, when the beetles became scarce and were leaving the plants to hibernate. The observations made, therefore, cover the entire period of the insect's active life.

Avian species composition and ecological distribution in south lake wetland park, hohhot

2017 ◽  
Vol 17 (1) ◽  
pp. 36-41
Author(s):  
Namkhaidorj Sainbileg ◽  
Wang Tong ◽  
Yang Fan ◽  
Yang Guisheng
Keyword(s):  
Diversity Index ◽  
Bird Species ◽  
Bird Community ◽  
Residential Area ◽  
Habitat Characteristics ◽  
Species Number ◽  
Resident Species ◽  
Wetland Area ◽  
Dominance Index ◽  
The Relationship

Species diversity and composition of bird community at South Lake Wetland Park in Hohhot city were investigated from October 2013 to September 2014. In total，64 bird species belonging to 33 families and 14 orders were recorded. There are 36 summer migrant species, 15 resident species, 11 traveling species and 2 winter migrant species found. The habitats of birds were grouped into four types (wetland, woodland, grassland and residential area) according to topography and vegetation types in the survey area．Shannon-Weiner Diversity Index (H`) was 2.9450 in wetland area and 1.0768 in grassland area the highest and the lowest values, respectively. The evenness of bird species was 0.4058 lowest in woodland and 0.7581 highest in residential area. The dominance index of bird species was 0.0733 lowest in the wetland and 0.4319 highest in the woodland, respectively. This paper analyzed the relationship between the main dominant bird species and their habitat characteristics，explained the main reasons for the increased bird species number.

IV.—Notes on Rhodesian Laterite

1909 ◽  
Vol 6 (8) ◽  
pp. 350-352 ◽  
Author(s):  
F. P. Mennell
Keyword(s):  
General Problem ◽  
Valuable Contribution ◽  
Widespread Occurrence ◽  
Tropical Regions ◽  
The Past ◽  
The Subject ◽  
The Tropics ◽  
Made In ◽  
Geological Magazine

A number of communications dealing with the origin and composition of the material commonly known as laterite have appeared in the Geological Magazine during the past few years. That of Dr. Maclaren is an especially valuable contribution to the literature of the subject, and I think few workers in the Tropics will be disposed to question the substantial accuracy of his conclusions. I shall not attempt, therefore, to discuss the general problem presented by the widespread occurrence of laterite deposits in tropical regions. The object of the present brief communication is merely to place on record a few observations made in another area.

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