2205 Chapters
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Medium 9781780643946

1 The Challenge of Modelling and Mapping the Future Distribution and Impact of Invasive Alien Species

Venette, R.C. CABI PDF


The Challenge of Modelling and

Mapping the Future Distribution and Impact of Invasive Alien


Robert C. Venette*

USDA Forest Service, Northern Research Station, St. Paul,

Minnesota, USA


Invasions from alien species can jeopardize the economic, environmental or social benefits derived from biological systems.

Biosecurity measures seek to protect those systems from accidental or intentional introductions of species that might become injurious. Pest risk maps convey how the probability of invasion by an alien species or the potential consequences of that invasion vary spatially. These maps inform strategic and tactical decisions for invasive species management. Pest risk modellers must contend with the challenges of developing models that forecast the course or consequence of invasions and are more meaningful than could be obtained by chance, of demonstrating the validity of those models and of portraying results on maps in ways that will be useful for decision makers. Frequently, these forecasts depend on extrapolations from limited information to project how a species might be affected, for example, by changes in commerce, exposure to novel environments or associations with new dispersal vectors, or how these species might affect resident species or ecological processes. Consequently, pest risk maps often focus on one phase of the invasion process: arrival, establishment, spread or impact. Risk

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Medium 9781603447652

18. Considerations for an Ecosystem Approach to Fisheries Management in the Southern Gulf of Mexico

John W Day Texas A&M University Press ePub

Juan C. Seijo, John F. Caddy, William W. Arzápalo, and Alfonso J. Cuevas

All fishing nations are under international pressure to implement an ecosystem approach in their domestic fisheries and in any international fishery in which they participate. The importance of the ecosystem approach to fisheries was recognized in 1991 by 47 countries participating in the Reykjavik Conference on Responsible Fisheries in the Marine Ecosystem. The signing parties declared “that in an effort to reinforce responsible and sustainable fisheries in the marine ecosystem, we will individually and collectively work in incorporating ecosystem considerations into that management” (FAO 2001, p. 106).

The ideal of an ecosystem approach to fisheries management is summarized by Chapter 17 of Agenda 21: “The marine environment—including oceans and all seas and adjacent coastal areas—forms an integrated whole that is an essential component of the global life-support system and a positive asset that presents opportunities for sustainable development. International law . . . sets forth rights and obligations of States and provides the international basis upon which to pursue the protection and sustainable development of the marine and coastal environment and its resources.” A number of attempts have been made to translate this ideal into a practical and feasible approach (Ward et al. 2002; Cochrane et al. 2004) including those of the US National Research Council (1999), the Convention of Biological Diversity, and the World Wide Fund for Nature.

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Medium 9781780642635

9: Ornithine: At the Crossroads of Multiple Paths to Amino Acids and Polyamines

D'Mello, J.P.F. CABI PDF


Ornithine: At the Crossroads of Multiple Paths to Amino Acids and Polyamines

R. Majumdar,1 R. Minocha2 and S.C. Minocha3*

USDA Agricultural Research Service, Geneva, New York, USA; 2USDA

Forest Service, Northern Research Station, Durham, New Hampshire, USA;


University of New Hampshire, Durham, New Hampshire, USA


9.1 Abstract

After the 20 amino acids that make up the proteins in all living organisms, ornithine perhaps occupies the most critical position among the non-protein amino acids. It sits at the crossroads of interconversions of glutamate and arginine on the one hand and the production of proline, polyamines and several alkaloids on the other: all products of tremendous importance to living cells. While ornithine is typically not an abundant amino acid, the metabolic flux of nitrogen through this amino acid is presumably quite rapid because of the cellular contents of the products for which it serves as the substrate. Our current knowledge of the regulation of ornithine biosynthesis is rather limited and mostly dependent upon the research targeted at understanding arginine and proline metabolism, and to some extent polyamine and alkaloid biosynthesis. Whereas most of the ornithine biosynthesis in animals occurs on the way to the production of glutamate, proline and putrescine from dietary arginine, in plants the pathway works in the reverse order, i.e. glutamate, the first product of nitrogen assimilation is the primary source of arginine, proline and putrescine. An understanding of the regulation of ornithine metabolism could help us in the genetic manipulation of plants for stress tolerance (via manipulation of proline and g  -aminobutyric acid, and the polyamine pathway), as well as in nutritional improvement (the cellular contents of important amino acids –

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Medium 9789380856827


Dr. Sanjay K. Sharma Laxmi Publications PDF





Ecology is the study of the interactions between organisms and their environment. Ecology is a science that studies relationships between living organisms and the environment they live in. In

1869, the german biologist Ernst Haeckel coined the term ecology, refering to the Greek origin of the word (oikos, house; logo, science, study, treaty). According to Haeckel, ecology had study species in its biological relations with environment. Other scientists took care later of the surroundings in which each species lives and of its symbiotic and antagonistic relations with others.

Towards 1925, August Thienemann, Charles Elton and others stimulated the ecology of the communities. They worked with concepts as the one of food web, or the one of pyramid of species, in which the number of individuals diminishes progressively from the base to the peak, the plants to the herbivorous animals and the carnivores.

The alive beings are in permanent interaction between each other and with the environment in which they live. The ecology analyzes how each element of an ecosystem affects the other components and how this is affected too. It is a synthesis science, because to understand the complex plot of relations that exist in an ecosystem it takes knowledge from botany, zoology, physiology, genetics and other disciplines like the physics, chemistry and geology.

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Medium 9789380386607


Rehana Khan Laxmi Publications PDF








Gene is defined as a unit of hereditary material located on a chromosome that, by itself or with other genes determines a characteristic in an organism. Genes may exist in a number of forms, termed as alleles. Genes are the hereditary units which are transmitted from one generation to next generation. The term gene was coined by Johannsen. Watson gave various definitions for gene as follows:

—as a fragment of gene

—as a complete protein

—as a heredity and variation.

The exact definition for gene is a discrete region of self-replicating molecule i.e., chromosome which is responsible for specific cellular production. Watson gave units of gene as follows:

Recon—the smallest unit of gene for transcription and translation.

Muton—the unit of gene for mutation.

Cistron—the functional unit of gene for transcription and translation.

Cistron is a unit, element of which exhibits cistrons phenomenon. Cistron is not a synonym for gene and it is difficult to use this term in practice.

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Medium 9780253008831

10 Freshwater Osteichthyes from the Cenomanian to Late Campanian of Grand Staircase-Escalante National Monument, Utah

Edited by Alan L Titus and Mark A Loew Indiana University Press ePub

Donald B. Brinkman, Michael G. Newbrey, Andrew G. Neuman, and Jeffrey G. Eaton

Fossil Assemblages from the Grand Staircase Region of Utah provide data on patterns of diversity of bony fish from the Cenomanian through the late Campanian from the southern parts of the Western Interior of North America. Basal actinopterygians are prominent members of the assemblages and generally can be identified to at least family level. A high diversity of teleosts is also present, including hiodontiforms, osteoglossiforms, elopomorphs, clupeomorphs, ostariophysans, esocoids, and acanthomorphs, as well as taxa that cannot presently be placed in any lower-level taxonomic group. The small size of teleosts from the Late Cretaceous of the Grand Staircase region indicates that they would have occupied basal positions in the vertebrate food webs. A major faunal change occurred between the Cenomanian and Turonian assemblages, with a 47% change in taxa across the boundary. Amiids decrease in diversity, pycnodonts and Lepidotes become rare, and the Lepisosteidae, Vidalamiinae, and ostariophysan type U-3/BvD all first appear in the Turonian. A significant faunal turnover also occurred in the mid- to late Campanian, when esocoids and a characiform first appear. Turonian to middle Campanian assemblages show a successive appearance of five new taxa, including acanthomorphs, and a loss of two taxa. Latitudinal patterns are identified by comparing assemblages from the Kaiparowits Formation with contemporaneous assemblages from more northern localities. Lepisosteidae gen. et sp. indet. type 1 (the gar represented by lanceolate teeth), Lepidotes, Micropycnodon, Melvius, and ostariophysan type U-3/BvD have a more southern distribution, while sturgeon, holostean A, holostean B, Belonostomus and the teleosts Paratarpon, teleost indet. type H, the clupeomorph Horseshoeichthyes, and Coriops have a more northern distribution. Several of the biostratigraphic changes that are observed can be interpreted as shifts in the geographic distributions of these taxa that are associated with changes in mean annual temperatures during the Late Cretaceous.

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Medium 9780253356512

3. Blood Silver

Nicholas A. Robins Indiana University Press ePub

“There Is Potosí because There Is the Mita”1

So wrote the mining guild to the crown in 1702, revealing in a single sentence their tendency to exaggeration and their single-mindedness. Although Potosí in the days before amalgamation had thrived on the basis of free labor, the mining guild became addicted to this human subsidy that almost all other mining centers in the Andes had prospered without. The mita underwrote extravagance, inefficiency, abuse, and debt as much as it did silver production.

The arrival in Potosí of those mitayos who did not flee on the weeks-long journey was a time of commotion, as they were assigned to hovels located between the ribera and the Cerro Rico, where they lived with other members of their community. Not only did they pay rent during their servitude, but they were prohibited from living with their wives or daughters, who often worked as servants for, and were subject to the depredations of, the Spanish and Creole elite.2

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Medium 9781780643595

14 Inference and Prediction with Individual-based Stochastic Models of Epidemics

Jarrad, F., Editor; Low-Choy, S., Editor CAB International PDF


Inference and Prediction with

Individual-based Stochastic

Models of Epidemics

Gavin Gibson1* and Christopher A. Gilligan2

1Maxwell Institute for Mathematical Sciences, Heriot-Watt

University, Edinburgh, UK; 2University of Cambridge,

Cambridge, UK


Stochastic models for the spread of epidemics in space and time are increasingly being used as predictive tools to help in the control of emergent pests and pathogens and as tools for the interpretation of observations of epidemics as they occur.

This chapter provides an introduction to a particular class of stochastic model – the individual-based, spatio-temporal compartment model – that is frequently applied in this context. An overview of the techniques used to implement these models and to fit them to observations is provided. The main implications of different model formulations for biosecurity and the design of control strategies are given. The chapter aims to provide the reader, who already has some knowledge of mathematical and statistical approaches to modelling infectious diseases, with a technical overview of the Bayesian computational approach.

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Medium 9789383828593


K.V.S.G. Murali Krishna Laxmi Publications PDF






Man is the most beautiful of all God�s creation. Shakespeare, the Bard of Avon, grew eloquent in singing about the beauty of man.

�What a piece of work is man,

How noble in reason

How infinite in faculties

In form and moving, how express

In action how like an angel

In apprehension how like a god

The beauty of the world

The paragon of animals�

Man is created to enjoy the bountiful nature bestowed on him by God.

Environment means the surroundings in which we live. It is a life-sustaining system in which various living beings like animals, including man, birds, insects, microorganisms like algae, fungi, protozoa, amoeba and non-living beings like air, water and soil are interrelated. Like man, his environment too is beautiful. The earth is a wonderful planet that has perennial sources of water to quench his thirst with their sweet water. Its atmosphere supplies pure air for him to breathe and has a natural ozone umbrella that protects him from sun�s dangerous ultraviolet rays. It has a green carpet to utilize the carbon dioxide that we exhale to recycle it into oxygen essential to sustain life on this planet. It has number of attractions like the rainbow to wonder at.

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Medium 9780253006820

8. Michigan’s Tart Cherry Industry: Vulnerability to Climate Variability and Change

Sara C Pryor Indiana University Press ePub


While commercial fruit production is a small fraction of the total agricultural output in the United States, it has major economic impacts at the local and regional level. This is particularly true for agricultural sites in the Midwest where the Great Lakes have a moderating influence on climate, allowing for commercial fruit production at relatively high latitudes for a continental location. Tart cherry production is of particular significance in the Great Lakes region. In 2009, 292 million pounds of tart cherries, or 80 percent of the national total, were produced in Michigan, New York, Pennsylvania, and Wisconsin (NASS 2010). Of this amount, 266 million pounds were produced in Michigan alone. In 2004–2008, cash receipts for Michigan tart cherries ranged from $34,697,000 to $63,030,000 (NASS 2009). Tart cherries are grown in three primary areas in the Lower Peninsula of Michigan (Figure 8.1). Over 50 percent of the statewide production occurs in the Northwest region, where tart cherries are the dominant fruit crop (Black et al. 2010). In contrast, fruit production is more diversified in the west central and southwest growing regions.

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Medium 9789383828593


K.V.S.G. Murali Krishna Laxmi Publications PDF

Sources of Air Pollution





One of the early steps involving air pollution problems is to locate the source from which air contaminants are being emitted. There are more than 7,50,000 man-made chemicals present in our environment and to these 1000�2000 new ones are added every year. Massive production of such chemicals directly or indirectly releases thousands of tonnes of a variety of air pollutants into the atmosphere. Some of the air pollutants emanated into the atmosphere by man are CO, CO2, SPM,

SOx, odours, noise, NH3, gases and vapours, dusts of toxic metals like Lead, Arsenic, Asbestos,

Nickel, Mercury, Phosphorus and their oxides, Vanadium, Zinc, various hydrocarbons, Fluorides etc. The pollution made by man is vast and the pollutants made by men are plentiful.


Air pollutants and their sources may be classified as follows:

∑ Primary and secondary pollutants

∑ Line and areal sources

∑ Natural and artificial sources.


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Medium 9781576337356

Reaction Rates: CLEP Chemistry

Ace Academics Ace Academics ePub
Medium 9780253002358

9 On the Road to Chiapas

Rudolf A. Raff Indiana University Press ePub

As 1968 bloomed, we watched in dismay the growing ferocity of the Vietnam War with the shattering surprise of the Tet Offensive at the beginning of the year, the decline of Lyndon Johnson’s hold on the presidency, and the depressing inevitability of Nixon’s election that autumn. However, my time in the U.S. Navy would come to an end early in the summer of 1969, and exciting science beckoned. One enticing new discipline bubbled up about that time from the sudden re-awakening of developmental biology: the study of how organisms develop from the fertilized egg to the adult, with the marvelous unfolding of the elaborate form of an organism from the apparently structureless spherical and homogeneous egg. I looked for postdoctoral opportunities in this new molecular developmental biology being pioneered by just a few labs. Developmental biology had made famous discoveries earlier in the twentieth century through ingenious microsurgical experiments but had languished by the 1960s because of a lack of tools to penetrate further into how embryos work. This was about to change in a completely unexpected way as genes became better understood and ways to study them were found.

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Medium 9781607320470

5 Order Didelphimorphia Opossums and Kin

David M. Armstrong University Press of Colorado ePub

Zoologists traditionally considered an infraclass Metatheria to contain a single living order, the Marsupialia, a group including mammals as diverse as opossums, wombats, marsupial “moles,” koalas, and kangaroos (G. Simpson 1945). More recent workers (Ride 1964, 1970; Kirsch 1977; Kirsch and Calaby 1977; McKenna and Bell 1997) have recognized 3 or more orders within this diverse group. Depending on the author, there are 8 (G. Simpson 1945), 14 (McKenna and Bell 1997), 16 (Kirsch 1977), or 20 (D. Wilson and Reeder 2005) families of marsupials, containing about 90 genera and more than 330 species (D. Wilson and Reeder 2005). Three families, Didelphidae, Caenolestidae, and Microbiotheriidae—totaling some 21 genera and 94 species—live in the Americas, but only 1 species, Didelphis virginiana, the Virginia opossum, occurs in the United States (Gardner 2005b). K. Rose (2006) reviewed the extensive fossil record of the marsupials.

Debate about their classification aside, marsupials have a suite of distinctive characteristics in common. Females give birth to young at a very immature stage of development and nourish them with milk for a relatively long period. The mammary glands usually are contained within an abdominal skinfold or pouch, the marsupium. The basic metatherian dental formula is 5/4, 1/1, 3/3, 4/4 = 50 (thus differing from placentals in having a greater total number of teeth, more incisors, with numbers of incisors different in the lower and upper jaw, and more molars than premolars). The palate is poorly ossified with many openings (fenestrae or vacuities). Auditory bullae are incompletely developed or lacking. The jugal bone is large and joins with the squamosal to form the glenoid fossa for articulation of the lower jaw. The horizontal ramus of the mandible is turned inward (inflected) at the angle of the dentary, a distinctive feature. Two small epipubic bones project forward from the anterior rim of the pelvic girdle. Females have a double reproductive tract with two ovaries, two oviducts, two uteri, and two lateral vaginae. In males the penis typically is forked at the tip and the testes are located in a scrotum anterior to the penis. The brain is relatively small, with poorly convoluted cerebral hemispheres, no corpus callosum, and large olfactory lobes.

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Ajay Kumar Saxena Laxmi Publications PDF

Appendix D


Fourier series expansion is given by



f n einθ

2π n =−∞

It is instructive to generalize this to more than one dimension, and it is especially useful in crystallography and solid state physics, which deal with three dimensional periodic structures.

Let us first consider a special case in which an N-dimensional periodic function is a product of N, one dimensional periodic functions. i.e. we take the N functions f (θ) =

f ( j ) ( x) =



k =−∞

f k( j ) e

2 πikx / L j

, j = 1, 2...N .


and multiply them on both sides to obtain

F (r ) = f (1) ( x1 ), f (2) ( x2 ),... f ( N ) ( xN ) =


i g k .r

∑ Fk e




where we have used the following new notations

F (r ) ≡ f (1) ( x1 ) f (2) ( x2 )... f ( N ) ( xN ), V = L1L2 ...LN

Fk ≡ fk1... fkN k ≡ (k1 , k2 ,.....k N ),

⎛k k ⎞ g k = 2π ⎜ 1 ,... N ⎟ ,

⎝ L1 LN ⎠

r = ( x1, x2 ...xN )

We take eqn (2) as the definition of the Fourier series for any periodic function of N variables (not just the products of N functions of a single variable). However, application of eqn (2) needs here some clarification. In one dimension, the shape of the smallest region of periodicity is unique. It is simply a line segment of length L

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