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  • In 1878 in Denison, Texas, a man named John Martin looked up into the sky and saw something he could not explain. Americans have been hooked on the possibility of beings from space visiting Earth ever since. A sense of wonder, and reality, are brought to some popular legends of alien encounters and sightings in this volume. The final chapter explores how these legends have become even more popular thanks to movies, television, and literature.
  • As the world's population expands, so too does the risk of communicable disease and global pandemics. Consequently, healthcare has assumed a greater centrality in the public consciousness both in the United States and around the world. With various national and international organizations dedicated to epidemiological research and disease control, societal welfare has become an increasingly significant aspect of public policy. The historical, legal, and scientific factors that form the basis of public health locally and globally are the subjects of this relevant and revealing volume.
  • Chemistry is often a daunting subject for students, fostering a bewilderment that sets in upon their first encounter with the Periodic Table. This book demystifies an important aspect of the subject--chemical reactions--and demonstrates exactly how fascinating and fun chemistry can be. Starting out by explaining just what a chemical reaction is--and what it isn't--the book details in accessible language the various kinds of chemical reactions that are possible. It draws upon readily comprehensible everyday examples, like rusting metal, baking bread, battery power, digestion, rotting eggs, and burning candles. The book then turns to a survey of the history of chemical research, beginning in the Ancient and Classical Worlds, progressing to the Medieval alchemists and Renaissance innovators, and ending with the leading lights of modern chemistry. Readers will be introduced to luminaries such as Antoine Lavoisier, John Dalton, Louis Pasteur, Dmitri Mendeleyev, the Curies, and Ernest Rutherford. It concludes with an inspiring examination of how current research and cutting edge developments are using chemistry and chemical reactions to save lives and insure continued life on Earth. This book amply illustrates the accessibility, relevance, and gee-whiz fun of chemical reactions.
  • The world's wildlife is vanishing at an alarming rate. Scientists at the Nature Conservancy and the World Wildlife Federation estimate that one in four mammals, and a full third of Earth's amphibians are in danger of becoming extinct. Today species are becoming extinct at a rate that is anywhere from 100 to 1,000 times faster than normal. People have been in fierce competition with wild animals for land, food, and natural resources for years. When over-hunting and -fishing of species and a rise in the level of pollution is added to this mix, humans come to represent the single gravest threat to wildlife survival. Any species that disappears leaves a hole in the web of life. Mass extinction would leave so many holes that the web might totally fall apart. Humans must realize the important role wildlife plays in the survival of the planet and reverse the damage--before it's too late.
  • Discusses the extent and effects of human trafficking, the term that is used today for modern-day slavery, which takes place in almost every country in the world.
  • Presents a history of ancient American civilizations prior to the arrival of Columbus, discussing history, agriculture, religion, architecture, art, and politics.
  • Readers learn about real-life case studies involving stem cell research, the sources of stem cells, ethical issues surrounding the use of stem cells, and stem cells' promising possibilities for medical use in bone marrow transplants, treating leukemia, and rebuilding injured organs. Legal issues and rulings around the world are also examined. The volume includes sidebars that provide expert viewpoints on the stem cell research debate, as well as fact boxes and summary boxes that highlight the key points in each chapter.
  • Presents information about the endocrine system, including what it is, conditions and diseases associated with it, how endocrine problems are diagnosed and treated, how to maintain a healthy endocrine system, and ways of coping with endocrine problems.

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