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  The Book of the Moon - A Guide...

  Maggie Aderin-Pocock

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  Have you ever wondered if there are seasons on the moon or if space tourism will ever become commonplace? So has Dr. Maggie Aderin-Pocock. In fact, she earned her nickname “Lunatic” because of her deep fascination for all things lunar. In her lucidly written, comprehensive guide to the moon, Aderin-Pocock takes listeners on a journey to our closest celestial neighbor, exploring folklore, facts, and future plans. 
    
  She begins with the basics, unpacking everything from the moon’s topography and composition to its formation and orbit around the Earth. She travels back in time to track humanity’s relationship with the moon—beliefs held by ancient civilizations, the technology that allowed for the first moon landing, a brief history of moongazing, and how the moon has influenced culture throughout the years—and then to the future, analyzing the pros and cons of continued space travel and exploration. The Book of the Moon will be published for the 50th anniversary of the moon landing. 
    
  Includes an interview with the author.

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  The Back Story on Spine Care - A...

  Dr. Drew Bednar

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  “A tour de force of spine care from a master spine surgeon who has literally seen it all over the course of a four-decade career! This book is a must-read that is accessible to both the layperson and healthcare professionals. I found it both enjoyable and informative.” — Dr. Andrew J. Schoenfeld, Harvard Medical School professor and Spine editor in chief
  		 
  A practical and occasionally provocative look at the state of spinal surgical care
  		 
  Just a few decades ago most spine surgery was literally a gamble: maybe you’d get better and maybe you wouldn’t. Today we have the knowledge, understanding, and technology to predictably relieve pain and neurological deficits like never before — yet many patients are still getting subpar care.  
  		 
  Foundational knowledge of surgical spine care isn’t spreading to the medical community, let alone to patients, whose quality of life hangs in the balance. With The Back Story on Spine Care, orthopedic specialist Dr. Drew Bednar presents case studies that illuminate the common issues plaguing patients — and their treatment — today.
  		 
  Back problems are among the most common health issues, and with Dr. Bednar’s insights, knowledge, and practical tips, medical professionals can provide care that leads to healthier backs and happier lives.

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  Introduction to Power System...

  Dr. Hidaia Mahmood Alassouli

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  Power system protection systems have three basic components: Instrument transformers, Relays, Circuit breakers
  
  The function of the CT is to reproduce in its secondary winding a current I' that is proportional to the primary current I. The CT converts primary currents in the kiloamp range to secondary currents in the 0–5 ampere range for convenience of measurement.
  
  The function of the relay is to discriminate between normal operation and fault conditions. The OC relay in Figure 2 has an operating coil, which is connected to the CT secondary winding, and a set of contacts. When |I'| exceeds a specified ''pickup'' value, the operating coil causes the normally open contacts to close. When the relay contacts close, the trip coil of the circuit breaker is energized, which then causes the circuit breaker to open.
  
  System-protection components have the following design criteria:
  • Reliability: Operate dependably when fault conditions occur, even after remaining idle for months or years. Failure to do so may result in costly damages.
  • Selectivity: Avoid unnecessary, false trips.
  • Speed: Operate rapidly to minimize fault duration and equipment damage. Any intentional time delays should be precise.
  • Economy: Provide maximum protection at minimum cost.
  • Simplicity: Minimize protection equipment and circuitry.
  
  Since it is impossible to satisfy all these criteria simultaneously, compromises must be made in system protection.
  
  The book consists from the following sections:
  1. Chapter 1: Power System Faults:
  2. Chapter 2: Instrument Transformers.
  3. Chapter 3: Overcurrent and Earth Fault Protection Relays.
  4. Chapter 4: Radial System Protection.
  5. Chapter 5: Zones of Protection.
  6. Chapter 6: Differential Relays.
  7. Chapter 7: Distance Relays.
  8. Chapter 8: Transformer Protection.
  9. Chapter 9: Generator Protection.
  10. Chapter 10: Busbar Protection.
  11. Chapter 11: Circuit Breakers.
  12. Chapter 12: Fuses.
  13. Chapter 13: References.

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  When the Ice is Gone - What a...

  Paul Bierman

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  In 2018, lumps of frozen soil, collected from the bottom of the world's first deep ice core and lost for decades, reappeared in Denmark. When geologist Paul Bierman and his team first melted a piece of this unique material, they were shocked to find perfectly preserved leaves, twigs, and moss. That observation led them to a startling discovery: Greenland's ice sheet had melted naturally before, about 400,000 years ago. 
   
   
   
  In When the Ice Is Gone, Bierman traces the story of this extraordinary finding, revealing how it radically changes our understanding of the Earth and its climate. A longtime researcher in Greenland, he begins with a brief history of the island, both human and geological. For the origins of ice coring, Bierman brings us to Camp Century, a US military base built inside Greenland's ice sheet, where engineers first drilled through mile-thick ice and into the frozen soil beneath. Decades later, a few feet of that long-frozen earth would reveal its secrets—ancient warmth and melted ice. 
   
   
   
  Changes in Greenland reverberate around the world, with ice melting high in the arctic affecting people everywhere. Bierman explores how losing Greenland's ice will catalyze devastating events if we don't change course and address climate change now.

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  Ancient Mesopotamian Astronomy...

  Charles River Editors

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  In ancient Mesopotamia, the Sumerians also provided the civilizational template for the earliest forms of astronomy. As the Sumerians gazed at the sky and began mapping the cosmos, they successfully tracked retrograde motion and predicted lunar and solar eclipses, bringing forth thousands of years of discoveries made by enterprising astronomers.  
  For the Mesopotamians, astronomy and astrology intertwined. Today, astronomy is understood as the scientific study of the universe, focusing on the physical properties of different bodies, from how they move to how they came into being. Conversely, astrology is a non-scientific belief system that interprets the stars and planets to predict human behavior, personality, or future events. However, in Mesopotamia, the astronomy determined the course of religion and the choices made by rulers, providing a certain mix between the mundane and the surreal. From their births to their deaths, the ancient Mesopotamians believed that deities surrounded them, and whether their social interactions were on the level of a smaller city or that of a larger nation-state, the deities played key roles in the social fabric of their society. Astronomy and astrology were thus wielded in order to divine supernatural intentions, and thereby plot proper courses in everyday life. 

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  Survival of the Sickest - A...

  Dr. Sharon Moalem, Jonathan Prince

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  How did a deadly genetic disease help our ancestors survive the bubonic plagues of Europe? Was diabetes evolution's response to the last Ice Age? Will a visit to the tanning salon help bring down your cholesterol? Why do we age? Why are some people immune to HIV? Can your genes be turned on—or off? 
  Survival of the Sickest reveals the answers to these and many other questions as it unravels the amazing connections between evolution, disease, and human health today. 
  Joining the ranks of modern myth busters, Dr. Sharon Moalem turns our current understanding of illness on its head and challenges us to fundamentally change the way we think about our bodies, our health, and our relationship to just about every other living thing on earth, from plants and animals to insects and bacteria. 
  Survival of the Sickest is filled with fascinating insights and cutting-edge research, presented in a way that is both accessible and utterly absorbing. This is a book about the interconnectedness of all life on earth—and, especially, what that means for us. 
  Read it. You're already living it. 
  Read by Eric Conger

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