THE ECOLOGY AND DISTRIBUTION IN SINGAPORE OF BIDENS PILOSA L. (ASTERACEAE)

COSMOS ◽  
2010 ◽  
Vol 06 (01) ◽  
pp. 39-44 ◽  
Author(s):  
A. F. S. L. LOK ◽  
K.-X. TAN ◽  
H. T. W. TAN
Keyword(s):  
The Other ◽  
Large Area ◽  
Bidens Pilosa ◽  
Suitable Habitats

Bidens pilosa is less widespread than the other composites commonly found in Singapore as it is animal-dispersed, as opposed to wind-dispersed like most of the Asteraceae. However, this species has been observed to spread over a large area within a year in suitable habitats of sandy or rocky moist substrate with adequate sunlight, such as Jalan Chichau and Jalan Lam Sam. Judging by its invasive success in other tropical and subtropical countries, it should do well in Singapore. More studies can be done on this species, and the populations in the abovementioned localities should be closely monitored to determine the success, and the spread of the species.

scholarly journals Diversity and Morphometry of Chiropteran Fauna in Jahangirnagar University Campus, Savar, Dhaka, Bangladesh

2016 ◽  
Vol 43 (2) ◽  
pp. 201-212
Author(s):  
Anik Saha ◽  
Md Kamrul Hasan ◽  
Mohammed Mostafa Feeroz
Keyword(s):  
Body Length ◽  
The Other ◽  
University Campus ◽  
Morphometric Measurements ◽  
Morphological Studies ◽  
Pipistrellus Pipistrellus ◽  
Cranial Measurements ◽  
Suitable Habitats ◽  
First Time ◽  
Flying Fox

The study was conducted to know the diversity of Chiropterans as well as their status and morphometric measurements in Jahangirnagar University campus between July, 2014 and April, 2015. Eight species of bats from three families were identified where Common Pipistrelle (Pipistrellus pipistrellus) and Pouch Tomb Bat (Saccolaimus saccolaimus) were recorded for the first time in Bangladesh. A total of 31bat individuals of 8 species were captured during 15 netting nights for morphological studies. Skull preparation was carried out for taking cranial measurements to identify the Pipistrelle species. No roosting colony of Pteropus gigantius was found in the study area but it visits the area only for foraging while the other species roost permanently. The old buildings in the study area provide suitable habitats for a significant number of insectivore bats. Indian Flying Fox (Pteropus gigantius) was the largest (mean head body length 23.33±1.86cm) and Least Pipistrelle (Pipistrellus tenuis) was the smallest (mean head body length 39.45±1.66 mm) species observed from the study area.Bangladesh J. Zool. 43(2): 201-212, 2015

A Study on Reliability of Pillar-Shaped Intermetallic Compounds Dispersed Lead-Free Solder Joint

2018 ◽  
Vol 941 ◽  
pp. 2087-2092
Author(s):  
Yusuke Nakata ◽  
Motoki Kurasawa ◽  
Tomihito Hashimoto ◽  
Kenji Miki ◽  
Ikuo Shohji
Keyword(s):  
Solder Joint ◽  
Intermetallic Compounds ◽  
Thermal Cycle ◽  
The Other ◽  
Lead Free ◽  
Lead Free Solder ◽  
Large Area ◽  
Longitudinal Elastic Modulus ◽  
Free Solder ◽  
The Ideal

A pillar shaped intermetallic compounds (IMCs) dispersed solder joint is a highly durable joint to achieve large area joining. The aim of this study is to investigate the ideal dispersion amount of pillar shaped IMCs. The dispersion rate of pillar shaped IMCs depend on the joining temperature. Pillar shaped IMCs dispersion rates are 3.5% and 5.5% when the joining temperature are 300 °C and 330 °C, respectively. Longitudinal elastic modulus are improved by forming pillar shaped IMCs. As a result of examination of the durability by the thermal cycle test, the durability of the joint with the dispersion rate of 3.5% was similar to that without pillar shaped IMCs, while that with the dispersion rate of 5.5% was remarkably improved. In the case of the dispersion rate of 3.5%, pillar shaped IMCs unevenly distributed and cracks tend to progress. On the other hand, in the case of the dispersion rate of 5.5%, pillar shaped IMCs were uniformly dispersed throughout the joint and suppressed crack propagation. Comparison of durability between pillar shaped IMCs solder and indium added solder to verify the effect of pillar shaped IMCs demonstrated that pillar shaped IMCs solder were more durable than indium added solder.

The Interpretation of the Land Tenure Law of Northern Nigeria

1970 ◽  
Vol 14 (3) ◽  
pp. 155-177
Author(s):  
C. M. McDowell
Keyword(s):  
Land Tenure ◽  
The Other ◽  
Customary Law ◽  
Northern Nigeria ◽  
Large Area ◽  
English Law ◽  
Relationship Of ◽  
The Relationship ◽  
New System

English law, as limited or modified, applies as one of the residual systems of law in Northern Nigeria, the other being customary law. The assumption underlying both the reception of English law and the retention of customary law was that both would be eroded and a new system would be created by local legislation and local decisions. While some erosion of both systems has taken place, such a process is necessarily slow and there remains a large area of law where the relationship of the received and retained law to local legislation is difficult to elaborate with any degree of precision. This is particularly true of the relationship of English law to the provisions of the Land Tenure Law and its predecessor, the Land and Native Rights Ordinance. The primary difficulty encountered in this context is the analogy which can be drawn between a lease in English form and the statutory right of occupancy, since the latter interest is granted by the appropriate authority normally, although not necessarily, for a definite term of years and may be governed by covenants which relate to rent, use and occupation, assignment and subletting, recovery of possession and so on.

scholarly journals Lichens of neglected habitats in Eastern and East-Central European lowlands

2013 ◽  
Vol 41 (1) ◽  
pp. 145-154 ◽  
Author(s):  
Jurga Motiejūnaitē
Keyword(s):  
The Other ◽  
Habitat Types ◽  
East Central ◽  
Central European ◽  
Other Hand ◽  
Spreading Dynamics ◽  
Distribution Limits ◽  
Suitable Habitats ◽  
East Central European ◽  
True Distribution

Situation of lichens of aquatic and transient habitats in Eastern and East-Central European lowlands is discussed basing on example of several selected species: <em>Leptogium biatorinum, Sarcosagium campestre, Steinia geophana, Verrucaria aquatilis, V. hydrela, V. praetermissa, V. xyloxena</em>. Both habitat types are generally very much neglected in the region and all species show large spatial gaps in recording, which makes it difficult to judge both about their true distribution limits and spreading dynamics. On the other hand, targeted search through the suitable habitats and abundance of such indicate that many of these lichens are probably not uncommon in the region.

scholarly journals AUTOMATIC DETECTION OF CLOUDS AND SHADOWS USING HIGH RESOLUTION SATELLITE IMAGE TIME SERIES

2016 ◽  
Vol XLI-B3 ◽  
pp. 475-479 ◽  
Author(s):  
Nicolas Champion
Keyword(s):  
Time Series ◽  
Satellite Images ◽  
Satellite Image ◽  
Region Growing ◽  
Shadow Detection ◽  
The Other ◽  
Landsat 8 ◽  
Cloud Detection ◽  
Large Area ◽  
The Difference

Detecting clouds and their shadows is one of the primaries steps to perform when processing satellite images because they may alter the quality of some products such as large-area orthomosaics. The main goal of this paper is to present the automatic method developed at IGN-France for detecting clouds and shadows in a sequence of satellite images. In our work, surface reflectance orthoimages are used. They were processed from initial satellite images using a dedicated software. The cloud detection step consists of a region-growing algorithm. Seeds are firstly extracted. For that purpose and for each input ortho-image to process, we select the other ortho-images of the sequence that intersect it. The pixels of the input ortho-image are secondly labelled <i>seeds</i> if the difference of reflectance (in the blue channel) with overlapping ortho-images is bigger than a given threshold. Clouds are eventually delineated using a region-growing method based on a radiometric and homogeneity criterion. Regarding the shadow detection, our method is based on the idea that a shadow pixel is darker when comparing to the other images of the time series. The detection is basically composed of three steps. Firstly, we compute a synthetic ortho-image covering the whole study area. Its pixels have a value corresponding to the median value of all input reflectance ortho-images intersecting at that pixel location. Secondly, for each input ortho-image, a pixel is labelled <i>shadows</i> if the difference of reflectance (in the NIR channel) with the <i>synthetic</i> ortho-image is below a given threshold. Eventually, an optional region-growing step may be used to refine the results. Note that pixels labelled <i>clouds</i> during the cloud detection are not used for computing the median value in the first step; additionally, the NIR input data channel is used to perform the shadow detection, because it appeared to better discriminate shadow pixels. The method was tested on times series of Landsat 8 and Pléiades-HR images and our first experiments show the feasibility to automate the detection of shadows and clouds in satellite image sequences.

Hot pressing of germanium monochromator crystals

2004 ◽  
Vol 37 (2) ◽  
pp. 339-340 ◽  
Author(s):  
S. F. Treviño ◽  
D. F. R. Mildner
Keyword(s):  
High Temperature ◽  
Single Crystal ◽  
Hot Pressing ◽  
The Other ◽  
Large Area ◽  
Vacuum Hot Pressing ◽  
Neutron Monochromator ◽  
Double Focusing

The method and parameters for vacuum hot pressing of single-crystal germanium, suitable for a large-area double-focusing neutron monochromator, are presented. The square virgin crystals have a mosaic that is less than 0.01° and isotropic. After appropriate pressing at high temperature (1073 K at a pressure of 10.7 MPa) the mosaic becomes anisotropic, about 0.5° in one direction and 0.2° in the other. The distribution of the mosaic widths of the crystals in the two directions are given, together with their composite values.

The Evolutionary Ecology of Movement

2001 ◽  
Author(s):  
Hugh Dingle ◽  
Marcel Holyoak
Keyword(s):  
Life Histories ◽  
Major Part ◽  
Evolutionary Ecology ◽  
Schistocerca Gregaria ◽  
The Other ◽  
Agricultural Pest ◽  
Mutual Attraction ◽  
The Mean ◽  
Suitable Habitats ◽  
Dynamics Of Populations

Organisms move, and their movement can take place by walking, swimming, or flying; via transport by another organism (phoresy); or by a vehicle such as wind or current (Dingle 1996). The functions of movement include finding food or mates, escaping from predators or deteriorating habitats, the avoidance of inbreeding, and the invasion and colonization of new areas. Virtually all life functions require at least some movement, so it is hardly surprising that organisms have evolved a number of structures, devices, and behaviors to facilitate it. The behavior of individuals while moving and the way this behavior is incorporated into life histories form one part of this chapter. This discussion focuses on the action of selection on the evolution of individual behavior, on how specific kinds of movement can be identified from the underlying behavior and physiology, and on the functions of the various movement behaviors. The other major part of our discussion focuses on the consequences of movement behaviors for the ecology and dynamics of populations. The pathways of the moving individuals within it can result in quite different outcomes for a population. First, movements may disperse the members of the population and increase the mean distances among them. The separation may be a result of paths more-or- less randomly chosen by organisms as they seek resources, or it may be a consequence of organisms avoiding one another. In contrast to dispersing them, movement may also bring individuals together either because they clump or congregate in the same habitat patch or because they actively aggregate through mutual attraction. Clumping can also lead to aggregation and mutually attracting social interactions. A classic example is the gregarious (aggregating) phase of the desert locust (Schistocerca gregaria), in which huge swarms of many millions of individuals first congregate in suitable habitats and then develop and retain cohesion based on mutual attraction. The foraging swarms make the locust a devastating agricultural pest over much of Africa and the Middle East (Farrow 1990; Dingle 1996). It is the aggregation of locusts that makes them such destructive pests; they would be far less harmful if the populations dispersed.

Low-background single-crystal silicon sample holders for neutron powder diffraction

2007 ◽  
Vol 40 (3) ◽  
pp. 489-495 ◽  
Author(s):  
M. Potter ◽  
H. Fritzsche ◽  
D. H. Ryan ◽  
L. M. D. Cranswick
Keyword(s):  
Single Crystal ◽  
Single Crystal Silicon ◽  
Neutron Powder Diffraction ◽  
The Other ◽  
Silicon Sample ◽  
Large Area ◽  
Crystal Silicon ◽  
Low Background ◽  
Plate Geometry ◽  
Null Matrix

Neutron diffraction measurements on weakly scattering or highly absorbing samples may demand custom mounting solutions. Two low-background sample holders based on inexpensive single-crystal silicon are described. One uses a conventional cylindrical geometry and is optimized for weakly scattering materials, while the other has a large-area flat-plate geometry and is designed for use with highly absorbing samples. Both holders yield much lower backgrounds than more conventional null-matrix or null-scattering materials and are essentially free from interfering Bragg peaks.

scholarly journals Constituents of Cajanus Cajan (L.) Millsp., Moringa Oleifera Lam., Heliotropium Indicum L. and Bidens Pilosa L. from Nigeria

2009 ◽  
Vol 4 (4) ◽  
pp. 1934578X0900400 ◽  
Author(s):  
Akinola O. Ogunbinu ◽  
Guido Flamini ◽  
Pier L. Cioni ◽  
Muritala A. Adebayo ◽  
Isiaka A. Ogunwande
Keyword(s):  
Essential Oils ◽  
Cajanus Cajan ◽  
Moringa Oleifera ◽  
The Other ◽  
Caryophyllene Oxide ◽  
Bidens Pilosa ◽  
Hexahydrofarnesyl Acetone ◽  
Leaf Oil ◽  
Heliotropium Indicum ◽  
Moringa Oleifera Lam

The essential oils of four plant species from Nigeria have been extracted by hydrodistillation and analyzed by GC and GC-MS. The oils of Cajanus cajan were comprised of sesquiterpenes (92.5%, 81.2% and 94.3% respectively in the leaves, stem and seeds). The major compounds identified were α-himachalene (9.0-11.5%), β-himachalene (8.0-11.0%), γ-himachalene (6.9-8.1%), α-humulene (7.1-8.7%) and α-copaene (4.5-5.6%). However, monoterpenoid compounds (81.8%) dominated the oil of Moringa oleifera with an abundance of α-phellandrene (25.2%) and p-cymene (24.9%). On the other hand, aldehydes (52.8%) occurred in the highest amount in Heliotropium indicum, represented by phenylacetaldehyde (22.2%), ( E)-2-nonenal (8.3%) and (E, Z)-2-nonadienal (6.1%), with a significant quantity of hexahydrofarnesylacetone (8.4%). The leaf and stem oils of Bidens pilosa were dominated by sesquiterpenes (82.3% and 59.3%, respectively). The main compounds in the leaf oil were caryophyllene oxide (37.0%), β-caryophyllene (10.5%) and humulene oxide (6.0%), while the stem oils had an abundance of hexahydrofarnesyl acetone (13.4%), δ-cadinene (12.0%) and caryophyllene oxide (11.0%). The observed chemical patterns differ considerably from previous investigations.

scholarly journals Flare puffs as a cause of type III radio bursts

1959 ◽  
Vol 9 ◽  
pp. 214-214
Author(s):  
R. G. Giovanelli
Keyword(s):  
Strong Association ◽  
The Other ◽  
Radio Bursts ◽  
Large Area ◽  
Type Iii ◽  
Apparent Area ◽  
Other Hand ◽  
Determining Factor

It has been well established that a strong association exists between flares and type III bursts: Loughhead, Roberts, and McCabe [1] showed that 60 to 70 per cent of type III bursts occurred during the lifetimes of flares or microflares of apparent area exceeding about 20 × 10–6 solar hemispheres. On the other hand, only about 22 per cent of all such flares are associated with bursts. This low figure indicates that there are differences of degree or type between various flares, but the large area range involved shows that flare size alone is not the determining factor.

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