How the lives of wild honey bees offer vital lessons for saving the world’s managed bee coloniesHumans have kept honey bees in hives for millennia, yet only in recent decades have biologists begun to investigate how these industrious insects live in the wild. The Lives of Bees is Thomas Seeley’s captivating story of what scientists are learning about the behavior, social life, and survival strategies of honey bees living outside the beekeeper’s hive—and how wild honey bees may hold the key to reversing the alarming die-off of the planet’s managed honey bee populations.Seeley, a world authority on honey bees, sheds light on why wild honey bees are still thriving while those living in managed colonies are in crisis. Drawing on the latest science as well as insights from his own pioneering fieldwork, he describes in extraordinary detail how honey bees live in nature and shows how this differs significantly from their lives under the management of beekeepers. Seeley presents an entirely new approach to beekeeping—Darwinian Beekeeping—which enables honey bees to use the toolkit of survival skills their species has acquired over the past thirty million years, and to evolve solutions to the new challenges they face today. He shows beekeepers how to use the principles of natural selection to guide their practices, and he offers a new vision of how beekeeping can better align with the natural habits of honey bees.Engagingly written and deeply personal, The Lives of Bees reveals how we can become better custodians of honey bees and make use of their resources in ways that enrich their lives as well as our own.
Book Summary of Homo Deus by Yuval Noah HarariAbout | Homo Deus: A Brief History of Tomorrow By Yuval Noah HarariSince the beginning of history, humanity has considered itself to be more special than the rest of the world. In many ways, the last few centuries of technological progress have only cemented our dominance over everything else. Yet, the future of humanity is anything but clear. Because humans have essentially tackled the long enduring problems of hunger, global plagues and war, science and technological interest will soon need to focus on new challenges. And based on the predictions of author Yuval Noah Harari, that future won’t look anything like the world we know today.Harari actually wrote Homo Deus: A Brief History of Tomorrow as a sequel to his earlier book, Sapiens: A Brief History of Humanity. After looking at the traits that made humans stand out in the first place (which he did with Sapiens), Harari now turns his attention to the future and the highly likely attempts to upgrade humans into gods. What might seem impossible today (immortality, complete control over moods, and happiness) might become far more plausible in the coming decades. The pace of technology and the increasing prevalence of immersive data systems like Google is changing the way that humans are relating with the world, and challenging long held beliefs about the value of humans in the first place.Will all human jobs soon be replaced by robots? Will the world be run by an elite class of upgraded super-humans? And what will we—as human beings—do if this happens? By looking through the course of history to predict future trends, these are the questions that Harari strives to answer.Here’s what you’ll learn about in this summary:- The three challenges that humanity has been fighting against since the beginning of time, and the likely challenges that will begin to fill our time instead.- The reasons why humans are more like machines than the special beings with souls and free will that we believe we are.- What it will mean for the importance of individual humans as technology and data systems continue to take over daily life.- What will come after humanism, and what it might mean for human society.- And much, much more...
“This exciting saga crosses space and time to illustrate how humans, born of stardust, were shaped—and how they in turn shaped the world we know today.” —Publishers Weekly This book offers “world history on a grand scale”—pulling back for a wider view and putting the relatively brief time span of human history in context. After all, our five thousand years of recorded civilization account for only about one millionth of the lifetime of our planet (Kirkus Reviews). Big History interweaves different disciplines of knowledge, drawing on both the natural sciences and the human sciences, to offer an all-encompassing account of history on Earth. This new edition is more relevant than ever before, as we increasingly grapple with accelerating rates of change and, ultimately, the legacy we will bequeath to future generations. Here is a path-breaking portrait of our world, from the birth of the universe from a single point the size of an atom to life on a twenty-first-century planet inhabited by seven billion people.
The 75th Ranger Regiment is a unique and distinct culture among the American military establishment. They stand alone, even among our other Special Operations forces, as the most active brigade-sized force in the current Global War on Terrorism. Since 9/11, the Regiment has been the only continuously engaged unit in the Army, and has had 40 percent of its number deployed in harm's way for the last decade. Their mission is unique. Rangers do not patrol, they don't train allied forces, nor do they engage in routine counterinsurgency duties. They have a single-mission focus: they seek out the enemy and they capture or kill them. This sets Rangers apart as pure, direct-action warriors.
Army Rangers are not born; they are made. The modern 75th Ranger Regiment represents the culmination of 250 years of American soldiering. As the nation's oldest standing military unit, the Regiment traces its origins to Richard Rogers' Rangers during the pre-Revolutionary French and Indian War, through the likes of Francis Marion and John Mosby, to the five active Ranger battalions of the Second World War, and finally, to the four battalions of the current Ranger regiment engaged in modern combat. Over that period, a standard of professional excellence and the forging of that excellence is distilled in the selection, assessment, and training of today's Rangers.
Granted unprecedented access to the training of this highly restricted component of America's Special Operations Forces in a time of war, retired Navy Captain Dick Couch tells the personal story of the young men who begin this difficult and dangerous journey to become a Ranger. Many will try but only a select few will survive to serve in the 75th Ranger Regiment. Sua Sponte follows a group of these aspiring young warriors through the crucible that is ranger training and their preparation for direct-action missions in Afghanistan against the Taliban.
Power systems have two components of apparent power: active and reactive power. Both components are necessary for functioning of electrical systems. The active power is the average power absorbed by the resistive load. The reactive power is the measure of energy exchange between the source and reactive power of load. Energy storage devices do not dissipate or supply power, but exchange power with the rest of system. Active power is the one that is converted to other forms of energy in the load yet reactive power is only responsible for magnetizing purposes. Power factor is a ratio depicting how much of the power supplied is real. The reactive current contribute in the value of the overall magnitude of current in transmission lines causing unnecessarily high line currents and low power factor. Since a low power factor means higher amount of apparent power need to be supplied by the utility company, thus the company must also use bigger generators, large transformers and thicker transmission/distribution lines. This requires a higher capital expenditure and operational cost which usually result in the cost being passed to the consumer.In this research, we seek to identify the effects of a low power factor on Swaziland Electricity Companys power supply system and recommend possible solutions to the problem. The results are useful in determining how to optimally deliver power to a load at a power factor that is reasonably close to unity, thus reducing the utilitys operational costs while increasing the quality of the service being supplied.
The eminent zoologist “extends his pioneering work in evolutionary biology” to examine “our preferences, predilections, fears, hopes, and aspirations” (Stephen R. Kellert, author of Birthright). Why do we jump in fear at the sight of a snake and marvel at the beauty of a sunrise? These impulsive reactions are no accident; in fact, many of our human responses to nature are steeped in our evolutionary past—we fear snakes because of the danger of venom, and we welcome the assurances of sun as the predatory dangers of night disappear. According to evolutionary biologist Gordon Orians, many of our aesthetic preferences—from the kinds of gardens we build to the foods we enjoy and the entertainment we seek—are the lingering result of natural selection. In Snakes, Sunrises, and Shakespeare, Orians explores the role of evolution in human responses to the environment, applying biological perspectives ranging from Darwin to current neuroscience. Orians reveals how our emotional lives today are shaped by decisions our ancestors made centuries ago on African savannas as they selected places to live, sought food and safety, and socialized in small hunter-gatherer groups. During this time our likes and dislikes became wired in our brains, as the appropriate responses to the environment meant the difference between survival or death. His rich analysis explains why we mimic the tropical savannas of our ancestors in our parks and gardens, why we are simultaneously attracted to and repelled by danger, and how paying close attention to nature’s sounds has made us an unusually musical species.
Quantum mechanics? Just hearing the name, we get sick. It seems to be something complicated (and is), but here I will try to explain this theory in simple terms. However, this does not mean that you will go to understand quantum mechanics. As Niels Bohr said, "who says he understands quantum mechanics, you have not understood it." Does it look like something strange, doesn't it? Yes so. Quantum mechanics challenges our common sense.
Quantum mechanics is the theory that describes the behavior of the universe at the microscopic level; are composed of atoms and subatomic particles and quantum mechanics explains the behavior of these basic units. Hence, the name: Mechanical (explain behavior) quantum (the microscopic world, the quantum).
There are three explanations for this schizophrenic behavior of nature at the level of atoms and subatomic particles, but none of them are officially accepted by the scientific community. We can say that the most important is that quantum mechanics works, and explanations may be to philosophers.
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