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Why Mars: NASA and the Politics of Space Exploration (New Series in NASA History)
by W. Henry LambrightTraces NASA’s torturous journey to Mars from the fly-bys of the 1960s to landing rovers and seeking life today.Mars has captured the human imagination for decades. Since NASA’s establishment in 1958, the space agency has looked to Mars as a compelling prize, the one place, beyond the Moon, where robotic and human exploration could converge. Remarkably successful with its roaming multi-billion-dollar robot, Curiosity, NASA’s Mars program represents one of the agency’s greatest achievements. Why Mars analyzes the history of the robotic Mars exploration program from its origins to today. W. Henry Lambright examines the politics and policies behind NASA's multi-decade quest, illuminating the roles of key individuals and institutions along with their triumphs and defeats.Lambright outlines the ebbs and flows of policy evolution, focusing on critical points of change and factors that spurred strategic reorientation. He explains Mars exploration as a striking example of "big science" and describes the ways a powerful advocacy coalition—composed of NASA decision makers, the Jet Propulsion Laboratory, the Mars academic science community, and many others—has influenced governmental decisions on Mars exploration, making it, at times, a national priority.The quest for Mars stretches over many years and involves billions of dollars. What does it take to mount and give coherence to a multi-mission, big science program? How do advocates and decision makers maintain goals and adapt their programs in the face of opposition and budgetary stringency? Where do they succeed in their strategies? Where do they fall short? Lambright’s insightful book suggests that from Mars exploration we can learn lessons that apply to other large-scale national endeavors in science and technology.
Why Men Never Remember and Women Never Forget
by Laura Tucker Marianne J. LegatoFrom the Publisher Men and women ARE different . . . and this book from the founder of gender medicine uncovers the neuroscientific reasons behind age-old disputes between men and women, while providing a groundbreaking, authoritative, and reader-friendly guide to resolving these differences. Why won't he ask for directions? Why does she always want to talk about the relationship? Why can't he see that something is bothering her?* But perhaps the biggest questions Why Men Never Remember and Women Never Forget resolves are: Why is it so hard for men and women to understand each other . . . and what can we do about it? According to Dr. Marianne Legato, an internationally recognized expert in gender-specific medicine, male and female brains are chemically and structurally different. And scientists are now finding out how these differences cause us to approach problems and experience the world in such dissimilar ways. So how do we bridge this physiological gap? Dr. Legato provides strategies and tips for learning to "think" like the other sex in order to get past our differences-and offers smart advice for dealing with issues wherever they arise. This trailblazing book will enable readers to understand each other-in both personal and professional relationships-like never before.
Why Michael Couldn't Hit: And Other Tales of the Neurology of Sports
by Harold L. KlawansThe author who told us why Toscanini fumbled and why Newton raved takes us on a tour of the great brains of great athletes in --baseball players and basketball players, track stars and golfers--to show how both accomplishment and tragedy may be the result of some unusual neurons.In Why Michael Couldn't Hit, Dr. Harold L. Klawans joins his two lifelong passions for neurological discovery and sports. And his arguments about the way the two are linked will give every sports fan a new outlook on what happens on the track, the baseball diamond, or in the arena. A deft and fascinating exploration, the book reveals that the twists and turns of athletes' brains have at least as much to do with their stardom as the strength and coordination of their muscles. It's an entirely original perspective on a topic that has always captured the American imagination: the breathtaking sight of athletic grace, force, and skill.
Why More Is Different
by Brigitte Falkenburg Margaret MorrisonThe physics of condensed matter, in contrast to quantum physics or cosmology, is not traditionally associated with deep philosophical questions. However, as science - largely thanks to more powerful computers - becomes capable of analysing and modelling ever more complex many-body systems, basic questions of philosophical relevance arise. Questions about the emergence of structure, the nature of cooperative behaviour, the implications of the second law, the quantum-classical transition and many other issues. This book is a collection of essays by leading physicists and philosophers. Each investigates one or more of these issues, making use of examples from modern condensed matter research. Physicists and philosophers alike will find surprising and stimulating ideas in these pages.
Why Mosquitoes Buzz in People’s Ears: A West African Tale
by Verna Aardema Leo Dillon Diane DillonNIMAC-sourced textbook
The Why of Things: Causality in Science, Medicine, and Life
by Peter RabinsWhy was there a meltdown at the Fukushima power plant? Why do some people get cancer and not others? Why is global warming happening? Why does one person get depressed in the face of life's vicissitudes while another finds resilience? Questions like these—questions of causality—form the basis of modern scientific inquiry, posing profound intellectual and methodological challenges for researchers in the physical, natural, biomedical, and social sciences. In this groundbreaking book, noted psychiatrist and author Peter Rabins offers a conceptual framework for analyzing daunting questions of causality. Navigating a lively intellectual voyage between the shoals of strict reductionism and relativism, Rabins maps a three-facet model of causality and applies it to a variety of questions in science, medicine, economics, and more. Throughout this book, Rabins situates his argument within relevant scientific contexts, such as quantum mechanics, cybernetics, chaos theory, and epigenetics. A renowned communicator of complex concepts and scientific ideas, Rabins helps readers stretch their minds beyond the realm of popular literary tipping points, blinks, and freakonomic explanations of the world.
Why Oh Why Are Deserts Dry?: All About Deserts (Cat in the Hat's Learning Library)
by Tish RabeIn this latest installation of the Cat in the Hat's Learning Library, the Cat takes Sally and Dick to explore different kinds of deserts around the world, from the hot, dry Sonoran and Mojavi to the bitter cold Gobi and Antarctica. Young readers learn why deserts are dry, and how plants and animals—including cactus, kangaroos, camels, penguins, roadrunners, and many others—have adapted to survive the unforgiving climate. Also included: how sand dunes are formed; the reason we see mirages, and how shallow water beneath the surface of the ground can create an oasis. Fans of the new PBS preschool science show The Cat in the Hat Knows a Lot About That! (which is based on the Learning Library series) won't want to miss this hot new addition to the series!
Why Only Us: Language and Evolution
by Robert C. Berwick Noam ChomskyBerwick and Chomsky draw on recent developments in linguistic theory to offer an evolutionary account of language and humans' remarkable, species-specific ability to acquire it.“A loosely connected collection of four essays that will fascinate anyone interested in the extraordinary phenomenon of language.”—New York Review of BooksWe are born crying, but those cries signal the first stirring of language. Within a year or so, infants master the sound system of their language; a few years after that, they are engaging in conversations. This remarkable, species-specific ability to acquire any human language—“the language faculty”—raises important biological questions about language, including how it has evolved. This book by two distinguished scholars—a computer scientist and a linguist—addresses the enduring question of the evolution of language.Robert Berwick and Noam Chomsky explain that until recently the evolutionary question could not be properly posed, because we did not have a clear idea of how to define “language” and therefore what it was that had evolved. But since the Minimalist Program, developed by Chomsky and others, we know the key ingredients of language and can put together an account of the evolution of human language and what distinguishes us from all other animals.Berwick and Chomsky discuss the biolinguistic perspective on language, which views language as a particular object of the biological world; the computational efficiency of language as a system of thought and understanding; the tension between Darwin's idea of gradual change and our contemporary understanding about evolutionary change and language; and evidence from nonhuman animals, in particular vocal learning in songbirds.
Why Peacocks?: An Unlikely Search for Meaning in the World's Most Magnificent Bird
by Sean FlynnAn acclaimed journalist seeks to understand the mysterious allure of peacocks—and in the process discovers unexpected and valuable life lessons.When Sean Flynn&’s neighbor in North Carolina texted &“Any chance you guys want a peacock? No kidding!&” he stared bewilderedly at his phone. He had never considered whether he wanted a peacock. But as an award-winning magazine writer, this kind of mystery intrigued him. So he, his wife, and their two young sons became the owners of not one but three charming yet fickle birds: Carl, Ethel, and Mr. Pickle. In Why Peacocks?, Flynn chronicles his hilarious and heartwarming first year as a peacock owner, from struggling to build a pen to assisting the local bird doctor in surgery to triumphantly watching a peahen lay her first egg. He also examines the history of peacocks, from their appearance in the Garden of Eden to their befuddling Charles Darwin to their bewitching the likes of Flannery O&’Connor and Martha Stewart. And fueled by a reporter&’s curiosity, he travels across the globe to learn more about the birds firsthand, with stops including a Scottish castle where peacocks have resided for centuries, a southern California community tormented by a serial killer of peacocks, and a Kansas City airport hotel hosting an annual gathering of true peafowl aficionados. At turns comically absurd and deeply poignant, Why Peacocks? blends lively, insightful memoir and illuminating science journalism to answer the title&’s question. More than that, it offers surprising lessons about love, grief, fatherhood, and family.
Why People Believe Weird Things: Pseudoscience, Superstition, and Other Confusions of Our Time
by Michael Shermer Stephen Jay GouldShermer has five basic answers to the question in his title: for consolation, for immediate gratification, for simplicity, for moral meaning, and because hope springs eternal. He shows the kinds of errors in thinking that lead people to believe weird things.
Why Place Matters: A Sociological Study of the Historic Preservation Movement in Otaru, Japan, 1965–2017
by Saburo HorikawaThis book is based on the author’s 33 years of intensive fieldwork. It chronicles a major movement that shaped the preservation policy in Japan in the 1980s and 1990s, providing “thick descriptions” of preservationists that are not available anywhere else in English. It also provides clear answers to a series of pressing questions about preservationists: are they building-huggers, are they selfish and myopic home-owners, or are they merely obstacles to urban planning and urban renewal? Since 1984, Saburo Horikawa, Professor of Sociology at Hosei University in Tokyo, has continuously studied the movement to preserve the Otaru Canal in Otaru, Japan. This book shows that the preservation movement was neither conservative nor an obstacle. Rather, the movement sought to promote changes in which the residents’ “place” would continue to be theirs. As such, the word “preservation” does not mean the prevention of growth and development, but rather its control. As is shown in this study, preservation allows for and can even promote change. The original Japanese version of this book (published by the University of Tokyo Press) has won 3 major academic awards; most notably, “The Ishikawa Prize”, the highest award bestowed by the City Planning Institute of Japan. It is extremely unusual that a sociology book should receive such important recognition from the city planning discipline.
Why Quark Rhymes with Pork
by David Mermin N.A collection of offbeat, entertaining and primarily nontechnical essays on physics and those who practice it, from eminent theoretical physicist N. David Mermin. Bringing together for the first time all thirty of his columns published in Physics Today's Reference Frame series from 1988 to 2009, with updating commentary, this humorous and unusual volume includes thirteen other essays, many of them previously unpublished. Mermin's lively and penetrating writing illuminates a broad range of topics, from the implications of bad spelling in a major science journal, to the crises of science libraries and scientific periodicals, the folly of scientific prizes and honors, the agony of getting funding, and how to pronounce 'quark'. His witty observations and insightful anecdotes gleaned from a lifetime in science will entertain physicists at all levels, as well as anyone else interested in science or scientists at the turn of the twenty-first century.
Why Religion Matters: The Fate of the Human Spirit in an Age of Disbelief
by Huston SmithHuston Smith, the author of the classic bestseller The World's Religions, delivers a passionate, timely message: The human spirit is being suffocated by the dominant materialistic worldview of our times. Smith champions a society in which religion is once again treasured and authentically practiced as the vital source of human wisdom.
Why Science Does Not Disprove God
by Amir D. AczelThe renowned science writer, mathematician, and bestselling author of Fermat's Last Theorem masterfully refutes the overreaching claims the "New Atheists," providing millions of educated believers with a clear, engaging explanation of what science really says, how there's still much space for the Divine in the universe, and why faith in both God and empirical science are not mutually exclusive.A highly publicized coterie of scientists and thinkers, including Richard Dawkins, the late Christopher Hitchens, and Lawrence Krauss, have vehemently contended that breakthroughs in modern science have disproven the existence of God, asserting that we must accept that the creation of the universe came out of nothing, that religion is evil, that evolution fully explains the dazzling complexity of life, and more. In this much-needed book, science journalist Amir Aczel profoundly disagrees and conclusively demonstrates that science has not, as yet, provided any definitive proof refuting the existence of God.Why Science Does Not Disprove God is his brilliant and incisive analyses of the theories and findings of such titans as Albert Einstein, Roger Penrose, Alan Guth, and Charles Darwin, all of whose major breakthroughs leave open the possibility— and even the strong likelihood—of a Creator. Bolstering his argument, Aczel lucidly discourses on arcane aspects of physics to reveal how quantum theory, the anthropic principle, the fine-tuned dance of protons and quarks, the existence of anti-matter and the theory of parallel universes, also fail to disprove God.
Why Sex Matters: A Darwinian Look at Human Behavior - Revised Edition
by Bobbi S. LowWhy are men, like other primate males, usually the aggressors and risk takers? Why do women typically have fewer sexual partners? In Why Sex Matters, Bobbi Low ranges from ancient Rome to modern America, from the Amazon to the Arctic, and from single-celled organisms to international politics, to show that these and many other questions about human behavior largely come down to evolution and sex. More precisely, as she shows in this uniquely comprehensive and accessible survey of behavioral and evolutionary ecology, they come down to the basic principle that all organisms evolved to maximize their reproductive success and seek resources to do so, but that sometimes cooperation and collaboration are the most effective ways to succeed.This newly revised edition has been thoroughly updated to include the latest research and reflect exciting changes in the field, including how our evolutionary past continues to affect our ecological present.
Why Sh*t Happens: The Science of a Really Bad Day
by Peter J. BentleyHave you ever fallen victim to Murphy's law? Sometimes bad things just happen. In Why Sh*t Happens, esteemed British scientist Peter J. Bentley takes readers on an informative and amusing tour through the least lucky, most accident-prone day of their lives. From sleeping through the alarm clock and burning breakfast to getting caught in the rain and navigating a slippery road, Bentley brilliantly explores disaster and mishap on a molecular level. In the process, he explains the science behind each accident, arming readers with the knowledge to understand what went wrong and how they can steer clear of future harm.Science is respected, trusted, and according to Bentley, largely misunderstood. Why Sh*t Happens urges readers to arm themselves with the power of science in order to better understand the world around them. When a car engine is damaged by the wrong gasoline or a computer is attacked by a virus, science is not to blame, but rather can provide an explanation of what happened.In a text that exudes charm and wit, Bentley reveals the causes behind a wide spectrum of mishaps, including why that razor nick won't stop bleeding, why metal sparks in the microwave, what makes chewing gum stick in hair, and why milk tastes sour when it goes bad.Sh*t will always happen, but now readers will know exactly why. Enter, if you dare, the world of everyday disasters.
Why Sharks Matter: A Deep Dive with the World's Most Misunderstood Predator
by David ShiffmanGet submerged in the amazing world of sharks! Your expert host, award-winning marine biologist Dr. David Shiffman, will show you how—and why—we should protect these mysterious, misunderstood guardians of the ocean.Sharks are some of the most fascinating, most ecologically important, most threatened, and most misunderstood animals on Earth. More often feared than revered, their role as predators of the deep have earned them a reputation as a major threat to humans. But the truth is that sharks are not a danger to us—they're in danger from us.In Why Sharks Matter, marine conservation biologist Dr. David Shiffman explains why it's crucial that we overcome our misconceptions and rise above cinematic jump scares to embrace sharks as the imperiled and elegant ocean guardians they really are. Sharing his own fascinating experiences working with sharks, Shiffman tells us• why healthy shark populations are a must for supporting ocean ecosystems—and the coastal economies that depend on them • why we're in danger of losing many shark species forever• what scientists, conservationists, and readers can do to help save these iconic predators• why so much of what you've heard about sharks and how to save them is wrong Exploring the core tenets of shark conservation science and policy, Shiffman synthesizes decades of scientific research and policymaking, weaving it into a narrative full of humor and adventure. Touching on everything from Shark Week to shark fin soup, overfishing to marine sanctuaries, Shiffman reveals why sharks are in trouble, why we should care, and how we can save them. Perfect for shark enthusiasts, Why Sharks Matter is an approachable, informative guide to the world of shark conservation and the passionate, fascinating, brilliant people who work to understand and protect our oceans. This fun read will have you looking at sharks with a fresh perspective and an understanding that the survival of sharks is crucial to the survival of another apex predator—ourselves.
Why Size Matters: From Bacteria to Blue Whales (Princeton Science Library #142)
by John Tyler BonnerJohn Tyler Bonner, one of our most distinguished and creative biologists, here offers a completely new perspective on the role of size in biology. In his hallmark friendly style, he explores the universal impact of being the right size. By examining stories ranging from Alice in Wonderland to Gulliver's Travels, he shows that humans have always been fascinated by things big and small. Why then does size always reside on the fringes of science and never on the center stage? Why do biologists and others ponder size only when studying something else—running speed, life span, or metabolism?Why Size Matters, a pioneering book of big ideas in a compact size, gives size its due by presenting a profound yet lucid overview of what we know about its role in the living world. Bonner argues that size really does matter—that it is the supreme and universal determinant of what any organism can be and do. For example, because tiny creatures are subject primarily to forces of cohesion and larger beasts to gravity, a fly can easily walk up a wall, something we humans cannot even begin to imagine doing.Bonner introduces us to size through the giants and dwarfs of human, animal, and plant history and then explores questions including the physics of size as it affects biology, the evolution of size over geological time, and the role of size in the function and longevity of living things.As this elegantly written book shows, size affects life in its every aspect. It is a universal frame from which nothing escapes.
Why Size Matters: From Bacteria to Blue Whales (Princeton Science Library #142)
by John Tyler BonnerWhy size plays such a big role in the living worldJohn Tyler Bonner, one of our most distinguished and creative biologists, here offers a completely new perspective on the role of size in biology. In his hallmark friendly style, he explores the universal impact of being the right size. By examining stories ranging from Alice in Wonderland to Gulliver's Travels, he shows that humans have always been fascinated by things big and small. Why then does size always reside on the fringes of science and never on the center stage? Why do biologists and others ponder size only when studying something else--running speed, life span, or metabolism?Why Size Matters, a pioneering book of big ideas in a compact size, gives size its due by presenting a profound yet lucid overview of what we know about its role in the living world. Bonner argues that size really does matter--that it is the supreme and universal determinant of what any organism can be and do. For example, because tiny creatures are subject primarily to forces of cohesion and larger beasts to gravity, a fly can easily walk up a wall, something we humans cannot even begin to imagine doing.Bonner introduces us to size through the giants and dwarfs of human, animal, and plant history and then explores questions including the physics of size as it affects biology, the evolution of size over geological time, and the role of size in the function and longevity of living things.As this elegantly written book shows, size affects life in its every aspect. It is a universal frame from which nothing escapes.
Why Society is a Complex Matter
by Philip BallSociety is complicated. But this book argues that this does not place it beyond the reach of a science that can help to explain and perhaps even to predict social behaviour. As a system made up of many interacting agents - people, groups, institutions and governments, as well as physical and technological structures such as roads and computer networks - society can be regarded as a complex system. In recent years, scientists have made great progress in understanding how such complex systems operate, ranging from animal populations to earthquakes and weather. These systems show behaviours that cannot be predicted or intuited by focusing on the individual components, but which emerge spontaneously as a consequence of their interactions: they are said to be 'self-organized'. Attempts to direct or manage such emergent properties generally reveal that 'top-down' approaches, which try to dictate a particular outcome, are ineffectual, and that what is needed instead is a 'bottom-up' approach that aims to guide self-organization towards desirable states. This book shows how some of these ideas from the science of complexity can be applied to the study and management of social phenomena, including traffic flow, economic markets, opinion formation and the growth and structure of cities. Building on these successes, the book argues that the complex-systems view of the social sciences has now matured sufficiently for it to be possible, desirable and perhaps essential to attempt a grander objective: to integrate these efforts into a unified scheme for studying, understanding and ultimately predicting what happens in the world we have made. Such a scheme would require the mobilization and collaboration of many different research communities, and would allow society and its interactions with the physical environment to be explored through realistic models and large-scale data collection and analysis. It should enable us to find new and effective solutions to major global problems such as conflict, disease, financial instability, environmental despoliation and poverty, while avoiding unintended policy consequences. It could give us the foresight to anticipate and ameliorate crises, and to begin tackling some of the most intractable problems of the twenty-first century.
Why String Theory?
by Joseph ConlonPhysics World's 'Book of the Year' for 2016 An Entertaining and Enlightening Guide to the Who, What, and Why of String Theory, now also available in an updated reflowable electronic format compatible with mobile devices and e-readers. During the last 50 years, numerous physicists have tried to unravel the secrets of string theory. Yet why do these scientists work on a theory lacking experimental confirmation? Why String Theory? provides the answer, offering a highly readable and accessible panorama of the who, what, and why of this large aspect of modern theoretical physics. The author, a theoretical physics professor at the University of Oxford and a leading string theorist, explains what string theory is and where it originated. He describes how string theory fits into physics and why so many physicists and mathematicians find it appealing when working on topics from M-theory to monsters and from cosmology to superconductors.
Why Study Biology by the Sea? (Convening Science: Discovery at the Marine Biological Laboratory)
by Karl S. Matlin Jane Maienschein Rachel A. AnkenyFor almost a century and a half, biologists have gone to the seashore to study life. The oceans contain rich biodiversity, and organisms at the intersection of sea and shore provide a plentiful sampling for research into a variety of questions at the laboratory bench: How does life develop and how does it function? How are organisms that look different related, and what role does the environment play? From the Stazione Zoologica in Naples to the Marine Biological Laboratory in Woods Hole, the Amoy Station in China, or the Misaki Station in Japan, students and researchers at seaside research stations have long visited the ocean to investigate life at all stages of development and to convene discussions of biological discoveries. Exploring the history and current reasons for study by the sea, this book examines key people, institutions, research projects, organisms selected for study, and competing theories and interpretations of discoveries, and it considers different ways of understanding research, such as through research repertoires. A celebration of coastal marine research, Why Study Biology by the Sea? reveals why scientists have moved from the beach to the lab bench and back.
Why Study Biology by the Sea? (Convening Science: Discovery at the Marine Biological Laboratory)
by Karl S. Matlin Jane Maienschein Rachel A. AnkenyFor almost a century and a half, biologists have gone to the seashore to study life. The oceans contain rich biodiversity, and organisms at the intersection of sea and shore provide a plentiful sampling for research into a variety of questions at the laboratory bench: How does life develop and how does it function? How are organisms that look different related, and what role does the environment play? From the Stazione Zoologica in Naples to the Marine Biological Laboratory in Woods Hole, the Amoy Station in China, or the Misaki Station in Japan, students and researchers at seaside research stations have long visited the ocean to investigate life at all stages of development and to convene discussions of biological discoveries. Exploring the history and current reasons for study by the sea, this book examines key people, institutions, research projects, organisms selected for study, and competing theories and interpretations of discoveries, and it considers different ways of understanding research, such as through research repertoires. A celebration of coastal marine research, Why Study Biology by the Sea? reveals why scientists have moved from the beach to the lab bench and back.
Why Study Biology by the Sea? (Convening Science: Discovery at the Marine Biological Laboratory)
by Karl S. Matlin Jane Maienschein Rachel A. AnkenyFor almost a century and a half, biologists have gone to the seashore to study life. The oceans contain rich biodiversity, and organisms at the intersection of sea and shore provide a plentiful sampling for research into a variety of questions at the laboratory bench: How does life develop and how does it function? How are organisms that look different related, and what role does the environment play? From the Stazione Zoologica in Naples to the Marine Biological Laboratory in Woods Hole, the Amoy Station in China, or the Misaki Station in Japan, students and researchers at seaside research stations have long visited the ocean to investigate life at all stages of development and to convene discussions of biological discoveries. Exploring the history and current reasons for study by the sea, this book examines key people, institutions, research projects, organisms selected for study, and competing theories and interpretations of discoveries, and it considers different ways of understanding research, such as through research repertoires. A celebration of coastal marine research, Why Study Biology by the Sea? reveals why scientists have moved from the beach to the lab bench and back.
Why the Dose Matters: Assessing the Health Risk of Exposure to Toxicants
by Urs A. BoelsterliEach day we are exposed to a myriad of natural and human-made chemicals in our food, drinking water, air, soil, at home or at the workplace—pesticide residues, food additives, drugs, household products—but how can we gauge the human health risk posed by these chemicals? Should we believe the somber headlines that depict a serious threat for humans and the environment, or should we follow the reassuring voices of others who claim that the angst is totally unfounded? Why the Dose Matters: Assessing the Health Risk of Exposure to Toxicants uses a rational, science-based approach to explain in plain language that a quantitative view is key for understanding and predicting potentially toxic effects of chemicals. Key Features: Explains the basics of toxicology in easily understandable terms. Includes numerous examples. Clears up common misconceptions and dispels myths. Provides take-home messages for each chapter. This book is aimed at interested laypeople. It uses numerous examples to illustrate the basic concepts and ensure that the reader will get a better understanding of why not only the hazard but also the overall exposure will determine whether some chemicals pose a serious risk while others are of little or negligible concern.