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Medium 9780253010421

2. The Ecology of Sabertooths

Antón, Mauricio Indiana University Press ePub

DURING THE SPAN OF GEOLOGICAL TIME THAT SABERTOOTHS OF ONE kind or another have inhabited the earth, our planet has undergone dramatic changes. Continents have collided and then drifted away from each other; temperatures have oscillated wildly, from periods of scorching heat to chilling ice ages; sea levels have risen and fallen, changing the shape of coasts and alternately flooding and revealing thousands of square kilometers of land; and vegetation has changed, from otherworldly Paleozoic forests consisting of giant ferns and primitive conifers to Cenozoic communities made up of essentially modern plant types, but with distributions that fluctuated dramatically with climatic oscillations. The evolution of sabertooths has been tightly linked to these changes in their environments and to the evolution of other animal species, including their competitors and prey. Everything we know about their history has been gathered from a treasure trove of information encrypted in layer on layer of sedimentary rocks: the fossil record.

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Medium 9781576337745

Introduction: SAT Chemistry

Ace Academics Ace Academics ePub
Medium 9780253357212

15 Iguanodontian Taxa (Dinosauria: Ornithischia) from the Lower Cretaceous of England and Belgium

Pascal Godefroit Indiana University Press ePub

David B. Norman

This review summarizes current understanding of the history, anatomy, and taxonomy of British and Belgian iguanodontian dinosaurs. The earliest iguanodontian from this circumscribed region is Berriasian in age and represented by a well-preserved but crushed dentary with many teeth in situ; originally named Iguanodon hoggii Owen, 1874, this specimen has been studied and reassessed several times, and decisions concerning its taxonomic status and systematic position have proved to be consistently inconclusive. I. hoggii has recently been renamed Owenodon hoggii; however, the diagnostic anatomical characters that form the foundation for this new name are few and not taxonomically or systematically robust. It is considered appropriate to regard this undoubtedly important taxonomic entity as indicative of a basal (ankylopollexian) iguanodontian and to encourage new exploration for additional skeletal remains from Berriasian-aged deposits in England. Wealden iguanodontian taxonomy in England has also begun to be scrutinized more thoroughly. Difficulties encountered when trying to diagnose the original (Valanginian) type genus (Iguanodon Mantell, 1825) and species (Iguanodon anglicus Holl, 1829) created problems that were resolved using a rather unfortunate workaround that involved the use of a Barremian–Lower Aptian species: I. bernissartensis Boulenger in Van Beneden 1881. With regard to remains collected from numerous Wealden localities in southern England, it was recognized that known iguanodontians can be subdivided into anatomically and chronologically distinct groupings: an earlier (Valanginian) “fauna” represented by Barilium dawsoni (Lydekker, 1888) and Hypselospinus fittoni (Lydekker, 1889), and a later (Barremian–Lower Aptian) “fauna” comprising Iguanodon bernissartensis Boulenger in Van Beneden, 1881, and Mantellisaurus atherfieldensis (Hooley, 1925). The Belgian locality at Bernissart, assigned to the Sainte-Barbe Clays Formation (late Barremian–Lower Aptian) has yielded two taxa that have been recognized as anatomically similar to those identified in the contemporaneous Wealden deposits of southern England (the Weald Clay Group of the Wealden District and the Wealden Group of the Isle of Wight). Recent suggestions that further taxa can be diagnosed within the English and Belgian Wealden sequences are assessed (and rejected) on the basis of the evidence presented.

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Medium 9781576753903

6 Key Enablers—Stability, Discipline, and Process Control

Cameron, Kim Berrett-Koehler Publishers PDF

6

Key Enablers—Stability,

Discipline, and Process Control

This is the second of four chapters that address the question What levers can leaders use to produce similar results? This chapter addresses the enablers that relate specifically to the careful, clear, and controlled leadership themes.

In direct contrast to the Adhocracy or Create quadrant in the Competing Values Framework, the Hierarchy or Control quadrant focuses on stability, control, measurement, clarity of objectives, discipline, and detailed planning and processes in organizations. These factors are often criticized as inhibiting and sabotaging spectacular performance, yet it is clear from our analysis that they were prerequisites for extraordinary success at Rocky Flats. Whereas the Adhocracy or

Create quadrant highlights symbolism, vision, and challenging the rules in the pursuit of innovation, enablers in the Hierarchy or Control quadrant emphasize efficiency, smooth functioning, predictability, and standardized procedures. They focus on the tight control of internal activities. Consistency and dependability are emphasized in contrast to innovation and dynamism.

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Medium 9781780640921

2 BOTANY AND PHYSIOLOGY

Biddle, A.J. CABI PDF

2

BOTANY AND PHYSIOLOGY

LEGUMES AND NITROGEN

Nitrogen is a major element in crop nutrition and in the absence of nitrogen, crop growth is severely affected as a result of a general chlorosis and reduction in photosynthetic ability. In most agricultural systems, nitrogen (N) is applied in a readily available form, either as nitrate in a chemical fertilizer or as manure or compost, where microbial breakdown can release soluble forms of nitrate that are then taken up by the growing crop. In large-scale commercial agriculture, most nitrogen is applied as a fertilizer produced by a chemical process (the

Haber–Bosch process) that converts nitrogen from the atmosphere into ammonia using high quantities of energy, or from non-renewable mined sources of minerals. In whichever production method is used, there is a high economic cost involved. An additional problem occurs with the use of applied fertilizers when excess chemical is leached out of the soil by rainfall or irrigation and is then able to enter water courses and catchments.

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Medium 9780253357014

Part 3: The Clades of Dinosaurs

Art Consultant Edited by M Bob Walters Indiana University Press ePub

J. Michael Parrish

Most readers will be familiar with groups such as dinosaurs, pterosaurs, and crocodiles, but the larger group to which all of these organisms belong, the Archosauria, is more obscure. Archosauria was initially erected by Cope (1869) to include dinosaurs, crocodilians, and all their presumed common ancestors. It has been slightly redefined by modern systematists to include the last common ancestor of the two extant groups of archosaurs–the crocodilians and the birds–and all of the descendants of that common ancestor. This is the sense in which I will use the name here.

The amniotes (the evolutionary group containing reptiles, mammals, and birds) have historically been differentiated on the basis of the arrangement of openings in the cheek region of the skull behind the orbit (Fig. 17.1). The pattern that is seen in fishes and amphibians, and that is primitive for the amniotes, is a solid cheek, without any openings. This pattern, termed anapsid, is also seen in early amniotes like captorhinids and pariesaurs, and is retained today in turtles, although some studies suggest that turtles may have acquired this condition secondarily (DeBraga and Rieppel 1997).

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Medium 9781603442909

Florida Gulf Coast Estuaries

Buster, Noreen A. Texas A&M University Press ePub

Tampa Bay and Charlotte Harbor

Gregg R. Brooks

Tampa Bay and Charlotte Harbor are the 2 largest estuaries in the eastern Gulf of Mexico. They lie in close proximity to one another, separated by less than 200 km, along the westward-facing, barrier-island Gulf Coast of peninsular Florida (Fig. 5.1). They have similar dimensions, share the same regional geological setting, have a similar climate (humid subtropical), and share a similar oceanographic setting (tide and wave regimes). Geologic research over the past 50 years has developed slower for Charlotte Harbor than for Tampa Bay. Over the past 20 years, studies have focused on the recent geologic history and modern depositional units because interests and funding have concentrated more on anthropogenic impacts and environmental concerns.

Figure 5.1. Location map of Tampa Bay and Charlotte Harbor along the Florida Gulf Coast (modified from Randazzo and Jones 1997).

Setting

Tampa Bay is a large multilobed system of interconnected bays and lagoons (Fig. 5.2). It covers over 1000 km2, but despite its large aerial extent is rather shallow with an average depth of 4 m. It has been naturally divided into 5 physiographic subregions. Middle and lower Tampa Bay form the main body, which is 1520 km in width, 30 km in length, and contains 58% of the total area. Fifty percent of middle and lower Tampa Bay is 26 m deep, and 30% attains depths >6 m. Almost all of the depths >6 m are in this part of the bay. Old Tampa Bay, the northwestern lobe, is approximately 25 km long, 510 km wide, and comprises 26% of the bay area. Almost 38% is <2 m deep and 2% is covered by water depths >6 m. Hillsborough Bay, the northeastern lobe, is approximately 15 km long by 7 km wide and comprises approximately 10% of the bay complex. Its depth distribution is similar to that of Old Tampa Bay. Boca Ciega Bay, located north of the mouth of Tampa Bay, is not technically part of the estuary but is a small lagoon behind the coastal barrier islands. Much of Boca Ciega Bay has been dredged and filled, resulting in a substantial decrease in estuarine habitat. Greater than 75% of Boca Ciega Bay is <2 m in depth (Goodell and Gorsline 1961).

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Medium 9780253021021

8 Iberian Sauropod Tracks through Time: Variations in Sauropod Manus and Pes Morphologies

Daniel Ma Edited by Peter L Falkingham Indiana University Press ePub

8.1. Geographical and geological setting of the main sauropod tracksites of the Iberian Peninsula located in four broad areas: Lusitanian Basin, Cantabrian Range, Iberian Range, and the Pyrenees.

Iberian Sauropod Tracks through Time: Variations in Sauropod Manus and Pes Track Morphologies

8

Diego Castanera, Vanda F. Santos, Laura Piñuela, Carlos Pascual, Bernat Vila, José I. Canudo, and José Joaquin Moratalla

THE IBERIAN SAUROPOD TRACK RECORD HAS YIELDED more than 100 sauropod tracksites ranging in age from the Middle Jurassic (Bathonian) to the Late Cretaceous (Maastrichtian). During this wide range of time, four different types of manus prints can be differentiated, changing in morphology from (1) speech-bubble–shaped with a prominent claw mark in digit I (Middle Jurassic), (2) kidney-shaped with a claw mark in digit I or (3) without a claw mark in digit I (Late Jurassic and Early Cretaceous), to (4) horseshoe-shaped (Cretaceous). Pes prints are slightly more conservative in morphology through the Mesozoic and are generally subtriangular. They can mainly be differentiated on the basis of the number and orientation of the claw marks, although the presence of a lateral notch behind digit V and the heel can be useful as well. There seems to be a lateralization of the claw marks after the Middle Jurassic, where the pes have four claw marks, two of them oriented anteriorly and two laterally. Subsequently, pes prints have three (Late Jurassic–Early Cretaceous) or four (Late Cretaceous) claw marks oriented anterolaterally and decreasing in size. The variation in the manus and pes morphology in the Iberian sauropod tracks is a reflection of the changes in the sauropod faunas over time. The different types of manus prints suggest that the forelimbs should play a major role in sauropod ichnotaxonomy.

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Medium 9780253009272

3 Public Health and Biochemistry: Connecting Content, Issues, and Values for Majors

Tricia A Ferrett Indiana University Press ePub

Connecting Content, Issues, and Values for Majors

Matthew A. Fisher

One of the challenges when incorporating integrative learning experiences in the undergraduate science curriculum for majors is the widely held perception by faculty that such changes would require significant sacrifices in the content that students learn. In my experience, however, changes made in a biochemistry course sequence for biochemistry, biology, and chemistry majors allowed the introduction of integrative learning opportunities without the loss of course disciplinary content. The revised sequence accomplished this goal by framing course content in the context of pressing public health issues such as Alzheimer’s disease, HIV/AIDS, and influenza. The revised courses challenged students to look at these issues from the perspective of biochemistry as well as other disciplines, their personal values, and institutional values.

Students have no problem anticipating that biochemistry will have a significant connection to what they are interested in, care about, and encounter on a daily basis; however, biochemistry textbooks and courses have traditionally steered clear of non-disciplinary discussions of the complexity of diseases such as AIDS and malaria or of malnutrition. The content of undergraduate biochemistry courses is thus most commonly presented in a manner that is largely disconnected from real-world contexts. Without a textbook or course pedagogy that makes clear these connections and establishes a context for knowledge, the stage is set for a pathology of learning that Lee Shulman (1999) has described as inertia—an inability to use what has been learned. There are several studies that clearly and persuasively argue that traditional curricula in chemistry (see Cooper, 2010 for a summary) and biology (National Research Council, 2003) include too much content and the result is often the inertia that Shulman describes. Upper-level undergraduate biochemistry courses are typically very content intensive; my fall course looks at protein structure and function, enzyme function (kinetics, mechanism, regulation), and roughly a half dozen distinct metabolic pathways (reactions involved, overall energetics, regulation) related to how the human body metabolizes carbohydrates, fats, and proteins. The spring course examines some different aspects of protein structure, glycoproteins, membrane structure and dynamics, transport, signal transduction, nucleic acid structure, and several processes central to nucleic acid biochemistry (replication, DNA repair, transcription, translation).

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Medium 9781576337974

Calculations: ACT Earth Science

Ace Academics Ace Academics ePub
Medium 9781780644370

8 Mechanism of Cry1Ac Resistance in Cabbage Loopers – A Resistance Mechanism Selected in Insect Populations in an Agricultural Environment

Soberon, M.; Gao, Y.; Bravo, A. CABI PDF

8

Mechanism of Cry1Ac Resistance in Cabbage Loopers –

A Resistance Mechanism Selected in Insect Populations in an

Agricultural Environment

Ping Wang*

Department of Entomology, Cornell University, New York State

Agricultural Experiment Station, Geneva, New York, USA

Summary

The development of resistance to Bacillus thuringiensis (Bt) in insect populations in agriculture not only depends on the level of resistance conferred by a selected resistance mechanism, but also on the fitness cost associated with the resistance mechanism under specific ecological and environmental conditions. Bt resistance in the cabbage looper (Trichoplusia ni), which was identified by Janmaat and Myers (2003), is a case of

Bt resistance evolved in an agricultural system, and is used in this chapter to review and discuss the mechanism of Cry1Ac resistance that is selected in an agricultural environment.

8.1 Introduction

Resistance of insects to pesticide sprays in agriculture has been observed for a century

(Melander, 1914). Under selection pressure by pesticide applications, thousands of cases of pesticide resistance in hundreds of arthropod species have been recorded (MotaSánchez et al., 2008). Since the first report of insect resistance to Bacillus thuringiensis (Bt) in 1985 (McGaughey, 1985), the potential

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Medium 9781786392015

2 Hydroelectric Generation

Henderson, P. CABI PDF

2

Hydroelectric Generation

Water has long been used as a source of energy – water wheels were in use over 2000 years ago. Hydroelectric power converts the potential

(­occasionally kinetic) energy of water via turbines to electricity. The most common type of hydroelectric power plant uses a dam on a river to store water in a reservoir. Water released from the reservoir flows through a turbine, spinning it, which in turn activates a generator to produce electricity. Hydroelectric power can be generated without a large dam; some hydroelectric power plants channel water along a canal and through a turbine rather like old water mills. Some of the largest and most impressive engineering projects undertaken by man are for hydroelectric generation. The Three Gorges Dam (Fig. 2.1) spans the Yangtze River, in the

P.R. China, and has the largest installed capacity of 22,500 MW. In 2014 the Three Gorges Dam held the record for total electricity generated of

98.8 TWh, but in 2016 this was surpassed by the Itaipú Dam on the Brazil/

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Medium 9781603442909

17

Buster, Noreen A. Texas A&M University Press ePub

Arturo Carranza-Edwards

The Mexican littoral zone of the Gulf of Mexico and the Mexican Caribbean together total 2756 km of generally sandy emergent shorelines associated with lowland terrains. The coast along the Gulf of Mexico forms a concave coastline (Fig. 17.1) with intermittent areas of high relief, and the continental shelf is wide, especially adjacent to the karstic Yucatan Peninsula (Tamayo 2002). This summary emphasizes relevant aspects of the Mexican coastline related to geological aspects of the littoral sediments and their role within the environmental context.

Figure 17.1. The Mexican littoral of the Gulf of Mexico.

Tectonic Setting

According to Carranza-Edwards et al. (1975), the Mexican coast of the Gulf of Mexico may be subdivided into 4 morphotectonic units. From the tectonic point of view, the units correspond to a coastline on a marginal sea that is protected from the Atlantic Ocean by the Caribbean Arc (Inman and Nordstrom 1971). Primary coasts are of terrestrial or continental origin, but secondary coasts dominate marine processes. The units summarized below are defined as continental units of regional character of the southwestern Gulf of Mexico. Even though these units have the same general tectonic style (mainly passive), there are major geomorphic divisions of the region.

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Medium 9780749469276

05 Increasing the efficiency of marketers’ intelligence

Patrick M Georges Kogan Page ePub

05

Increasing the efficiency of marketers intelligence

Marketing development requires renovating the marketing function by changing the role it traditionally occupies in numerous companies. As a fully fledged member of the executive committee, with close ties to management, the marketing function tends to become more strategic. Its operational role diminishes as this discipline becomes decentralized to the sales department and local entities. Marketing evolution means that new links must be created between the manufacturing of products and services in factories, the management of distribution channels, IT and marketing.

Traditionally oriented towards the consumer, who is becoming more proactive, the role and method of marketing will be extended to other partners, eg personnel, shareholders, the environment, and distribution intermediaries. Mentalities must change drastically so that this function can successfully bring the brand closer to customers. Marketing involves reflecting on the required qualities of the staff in this function, from the director to the product, market, distribution channel and brand managers. It calls for the development of participative structures for each project. It demands the close collaboration of all personnel so that this discipline, which consists of bringing the company closer to its customers, can become everybodys business.

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Medium 9781576336625

Light and Optics: MCAT Physics

Ace Academics Ace Academics ePub

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