Nature Journal Essays - Agkistrodon, Agkistrodon Contortrix

Nature Journal Introduction Wildlife is always deemed to be of great significance economically, ecologically, environmentally as well as culturally. It includes a wide range of species from amphibians, insects, birds to mammals. Thus, there is no doubt that there are some organisms that are native while others were introduced or re-introduced to their current habitant (Day, Klingler & Bloomberg 283). The essay is an in-depth examination of five wild animals that exist in the United States of America. These animals are Red Fox (Vulpes vulpes), Northern Harrier (Circus cyaneus), Black and Yellow Garden Spider (Argiope aurantia), Northern Copperhead (Agkistrodon contortrix mokasen) and American Bullfrog (Rana catesbeiana). To be able to cover these species adequately, the following will be established: - Are the species, being studied, native or introduced in that environment? - Describe their physical characteristics in terms of color as well as specific differences between the sexes. Additionally, the issues regarding the species' habitats are adequately tackled. This is attained by establishing their local habitat as well as their habitat range, their ecological role, the types of food they eat and other relevant relationships such as parasitism, mutualism are brought to light. The species' category under IUCN is also brought to light. At the same time, discover life cycle of these species and life span as well as how they coexist with people. Red Fox (Vulpes vulpes) According to Rue (72), Red fox is the largest of animals that is considered as true foxes. This species is in the family of Canidae which is comprised of wolves, dogs and coyotes. These animals are characterized by an orange or red fur. Red foxes have white fur on their chest as well as beneath their neck. The tail is usually fluffy and white at the tip. The ears are black and pointed. Their legs are colored black. The animal is about three feet long and weighs 10 pounds. As suggested by Clapham (122), Red fox inhabits a greater part of the United States as well as Canada, but there is no record to show that they ever existed in Alaska and Texas. According to IUCN, it is categorized as Least Concern for extinction and named as world's worst alien invasive species. They have a wide range covering approximately 70 million square kms including wood lands, farmland as well as prairies. Historically, red foxes were being preyed by lynx, wolves, and bobcats but due to the reduced number of these predators, people became the major predator hunting these animals for various reasons, such as sport hunting, as well as for their fur or by farmers in protecting their crops and livestock (Rue 121). It is thus no doubt that red fox has a long association with mankind. This can be depicted in human folklore as well as in myths. Red foxes are opportunistic feeders whose feeding pattern varies with season as they eat everything available during some period. Generally speaking, this species is omnivorous eating fruits, grasses and berries. They also feed on birds, insects, small mammals. They can investigate over five miles looking for food despite the fact that they are not hungry. Surplus food stuffs are hidden to be consumed later (Clapham 54). With regards to reproduction, red foxes reproduce only once a year during spring. Female estrus lasts for 21 days during which the male mates with her for a number of days in burrows during which there is at least an hour of copulation tie. The gestation period is approximately two months. Prior to littering, the female/vixen will get two den ready. The litter size ranges between 4 and 8. As the female is nursing the litter, males look for food. Within a period of about 2 weeks, the kits open their eyes, and 4 days after, lower teeth start emerging. The juvenile takes a period of six to seven months, and then, the adulthood comes. It has been established that in their natural habitat, the red foxes attain a maximum of five years and fourteen while under captivity (Rue 65). These mammals are nocturnal and can hear voices in lower frequencies. They stalk their prey just like the cat does, then pounce and chase. Dens are utilized for reproduction reasons. Red foxes sleep in open environment using their tail to save warmth (Clapham 23). Northern Harrier (Circus cyaneus) Also known as marsh hawk, the bird is between 17 and 24 inches with a wing span ranging from 3.5 to 4.5 feet weighing between 12 and 18 ounces. Males are typically smaller than females. This

Learning English Question and Answer †Number 1

Learning English Question and Answer – Number 1 Free Online Research Papers Learning English Question and Answer Number 1 1. Energy is one of the most important cornerstones of the modern society. The aircraft, vessel and automobile need oil to run; Burning of coal provides electricity and heat to us; the machines in factories are working on electricity; the light, TV set, computers and etc. also depend on electricity to work. In today’s world, we are not able to live without energy. In the past 2004, the world met big crisis of energy. Globally, the price of petroleum soared. The development of world economy was seriously influenced. Domestically, the shortage of power supply in summer forced thousands of factories to close every day. People are working hard to search for more energy supply. More petroleum and coal mines have been found; more electricity plants are under construction; the new types of energy such as nuclear are developed. We must realize that the supply of energy is limited. If we do not make better use of them, our society will be in bigger energy crisis. 2. 2008: As the biggest International sports meeting, the Olympic Games will be held in Beijing in 2008. This is the first time that the Olympic Games come into China. At that time, it is expected that tens of thousand of players and millions of visitors from different countries will come to Beijing. In order to prepare the sports meeting, China will invest billions of US dollars. A new main stadium is under construction as well as several other new sports facilities. Beijing’s traffic system will also be improved. Chinese sport player teams, who won 32 golden medals in 2004 Olympic Games, started their training for 2008. It is expected that they are going to perform better in 2008. 2008 Olympic Games gives China a great chance to show itself. As host, how could 1.3 billion Chinese return the world a pleasant surprise? A civilized, vigorous and self-confident China will be best gift to the world. Research Papers on Learning English Question and Answer - Number 1PETSTEL analysis of IndiaTwilight of the UAWBionic Assembly System: A New Concept of SelfDefinition of Export QuotasInfluences of Socio-Economic Status of Married MalesLifes What IfsNever Been Kicked Out of a Place This Nice19 Century Society: A Deeply Divided EraThe Effects of Illegal ImmigrationHip-Hop is Art

Survival of the fittest Coursework Example | Topics and Well Written Essays - 750 words

Survival of the fittest - Coursework Example For example, negative behaviors like violence and murder are rare, though scarcely present in the society. On the other hand, social aberration of negative acts like murder and violence are mainstream values (Alvaro, 2010). In this context, the mainstream adoption of positive behavioral habits over negative habits is synonymous to survival of fittest and desirable genets in Darwin’s mechanism of natural selection. In the context of ethics, the mechanism of survival for the fittest can be used to comprehend survival strategies employed by individuals and groups in the society. Primarily, the survival for the fittest mechanism asserts that like all animals, human beings included, compete against each other for survival and prosperity. Therefore, human strategies for survival and prosperity are inherently selfish in nature (Phillips, 2002). Under the right circumstances, every individual is innately programmed to act in a manner likely to preserve him or herself. In modern societies, material wealth is a tangible measure of personal prosperity. Since individuals are highly likely to selfishly pursue activities that maximize their material wealth, then one can easily understand the origins of deeply rooted vices like corruption in public and private organization. Like other governments, United States struggled and still struggles with corruption in public institutions. Actually, politicians and any individual in a correct position can, and will probably siphon as much public wealth as possible, so long as their actions are either conducted in secret, or are within the legal boundaries (Pepin, 2013). Therefore, corruption and other unethical behaviors executed by individuals or groups are manifestation of selfish desired meant to preserve and enhance one’s survival in a competitive environment. However, survival for the fittest can be used to understand the popular aspect of

Describing how the civilizations were similar and how they differed Essay

Describing how the civilizations were similar and how they differed - Essay Example The civilizations extended and some areas developed dependently and together while the Chinese civilization developed independently (Schirokauer et.al 24). Although there was some influence on the West’s cultures. In most cases, the Chines development occurred in the sections known as the dynasties. The dynasties were divided into three categories namely, early dynasty, imperial dynasties and end of ancient china. The Qin dynasty was established as a type of China civilization dynasties by Shi Huangti. The Qin dynasty can be also referred to as the China era. Shi conducted the wall destruction and established the Great Wall of China (Schirokauer et.al 48). He also made travelling easy by building roads to improve the infrastructure of China. He fairly ruled the people and distributed lands. He also expanded his empire and its boundaries (Schirokauer et.al 48). All this and among others are the development of civilization in the empire of Qin dynasty. The empire of Persian developed civilization in terms of classical civilization. The classical development of civilization in the Persian Empire. Succeed due to the cooperation of leaders in the empire. Several areas of economic activities were taxed 20 percent. Such activities are like religious institution, manufacturing and agriculture among others. The activities were the cause civilization development. Finally, civilization in the Empire of Macedon. The civilization development started in the year 1913. In this empire, the Greek community was powered and the stabilization of the area. Unlike other empires, Macedon has developed its civilization through development of the area. The mentioned empires above having their differences and similarities. In most cases, development in all the empires influenced the economic development of the area. On the other hand, each empire had a different style of developing

Laser Alignment Theory Essay Example for Free

Laser Alignment Theory Essay Modern optical metrology uses precise lines and planes in space from which measurements are made. Because this method creates these features using light it has become known as optical tooling. The 35 year old historical development and current technology of laser instrumentation as used in optical tooling is discussed in detail. This includes the how the measurements are made, applications, and the technology of alignment lasers and position sensing targets developed for sensing position within a laser beam or plane. The various geometries used to make alignment measurements are discussed in detail. Applications are discussed and the challenges each poses are discussed. The challenge of long range alignment and the effect of the turbulent atmosphere on the measurement process is discussed along with methods of handling the associated errors them. WHAT IS OPTICAL TOOLING? Optical tooling is a means establishing and utilizing a line of sight (LOS) to obtain precise reference lines and reference planes from which accurate measurements are made with position sensitive targets. 1] Formerly the measurements were done by a person interpreting a scale or optical micrometer by looking through an alignment telescope; today the lines and planes are created by a laser; the measurements are digital and require no interpretation. Optical tooling uses the principle that light travels in straight lines to produce precise measurements that cannot be reached by manual or mechanical methods. Level lines can be esta blished over great distances so accurately that every point is exactly perpendicular to the force of gravity. Plumb lines can be set to a given level. Right angles can be produced quickly and precisely with auxiliary components. In the assembly, maintenance and calibration of industrial equipment or in the alignment of precision systems, one or as many as four basic questions always must be answered: is it straight, is it flat, is it plumb or is it square? A number of techniques have been developed to make these measurements; however, many of them result in inaccuracies so great that proper operation of the equipment involved will be compromised or seriously endangered. The science of optical metrology and alignment makes it possible to achieve the highest degree of accuracy in answering these four important questions. It is no longer necessary to interpret readings or to make constant adjustments and calculations. In laser alignment applications, direct, precision measurements are made rapidly and consistently. Straightness In aligning several points, a tight wire is often used as a reference line. This technique has numerous drawbacks and introduces inaccuracy. First of all, wire has weight, which causes it to sag; over long distances this sag can become considerable. In addition, wire vibrates, can bend or kink, and when stretched in the area to be measured, equipment cannot be moved around for fear of disturbing the wire reference line. Even a gentle breeze can cause the wire to move sideways a considerable amount; the aerodynamic drag on a thin wire is huge. In laser alignment, the LOS of is established by a laser beam instead of a tight wire. The invisible LOS reference has no weight, cannot sag, kink, or be disturbed, nor is it a safety hazard. It constitutes a precise, unvarying reference, determining straightness to within thousandths of an inch. Flatness In order to determine flatness a shop level and a straightedge was employed in the past. However, over large horizontal areas, the shop level must be moved from part to part. Consequently, one can only tell the degree of flatness of each individual surface upon which the level is place. Whether all objects in a large area are flat is still in doubt. Flatness over a considerable area must be assured in the erection of large machinery, surface tables and large machine tools. Conventional bubble levels simply do not offer the degree of precision required. Laser levels, a termed that has fallen into generic use, offer a way to produce a level datum over a wide area. Laser technology has overcome the many disadvantages of bubble levels and assures levelness to within a few thousandths of an inch over hundreds of feet. This high degree of levelness is accomplished by horizontally sweeping the laser beam manually or via a motor driven rotary stage. This revolving line of laser ligh t becomes a horizontal plane of sight, giving a precise horizontal reference datum, sometimes called a waterline. Squareness Perfect squareness implies that one plane forms a 90Â ° angle with another intersecting plane. When a steel square is used to test for this condition, the results can be very misleading. Such measurements rely upon the trueness of the steel square, which can vary from square to square with time. In addition, steel squares have a definite limit in their physical dimensions and consequently the testing of very large surface becomes inaccurate, slow and cumbersome. Laser alignment overcomes all these disadvantages and offers a quick and precise method for determining squareness. One method is to use a transparent penta prism in conjunction with a simple alignment laser. This optical element will split the beam from the laser into two parts; one beam passes through the prism undeviated, the other beam is reflected at a perfect 90 degree angle. This will be described in more detail later. Other systems use three independently mounted lasers that are orthogonal to each other. Plumb Classically, a plumb bob is used to establish a single vertical reference line. Of course, as vertical distances increase, the plumb bob becomes cumbersome and inaccurate. It takes a long time for the plumb bob to settle. Also, it can easily be swayed by vibration, air currents, and other disturbances which are bound to be encountered. In the laser alignment method there are several ways to produce a plumb reference; it can be a plane or a line. To form a plumb line, an alignment laser with autocollimating capability is used with a pool of almost any liquid. Autocollimation senses the angle of an external mirror by reflecting its beam back into the laser head. A position sensor, beamsplitter and lens measure the angle of the reflected beam. When the laser is adjusted such that the internal sensor reads 0 in both axes, then the laser is producing a plumb line. For example, if a heavy machine tool is being surveyed, the two reference points which determine the LOS should be located off of the machine. If for any reason the machine were to move or deflect all measurements would be in error. The two reference points should be located close enough to be convenient to use and/or out of the way of other people working in the area. Transits and alignment telescopes first made these types of measurements. But the problem with transits and telescopes is that they require a person to interpret a scale placed on the object of interest; and usually a second person is holding the scale against the object. It is a two person job that takes time and much training to accomplish successfully. It is also subject to errors. This type of alignment measurement, commonly called straightness, is the most basic of all alignment applications. The figure below shows an alignment laser source on the left whose collimated beam is striking a position sensor target on the right. The target can freely slide and make measurements of straightness of the structure to which it is attached. [pic] Another common requirement is to establish another LOS perpendicular or parallel to the original LOS. To establish a perpendicular a special prism is used: a penta prism. A penta prism has the property that rotation around its axis does not deviate the reflected beam at all; it does not have to be critically mounted. Penta prisms are often called optical squares, an appropriate term. To establish a parallel LOS to an existing LOS typically involves tooling bars if the distance is relatively short, say a meter or less. These bars are made of steel and hold electronic targets at a precise distance from a center. Using two of them with the original LOS establishes a parallel LOS. If the distance between the two LOS is large, then it can be done using the penta prism twice; the first time to turn the beam 90 degrees, followed by a certain distance, and concluded by turning the beam back 90 degrees. Care must be taken that two LOS are truly parallel; usually using a level reference datum makes the task much easier. The next alignment application involves measuring the alignment error between two different LOS datums; the typical application is to determine the lateral offset and angular error between two shafts. The shafts essentially define the two LOSs. The measurement consists of setting up the source on one shaft and parallel to it. The targets are placed on the second shaft and surveyed. Then the shafts are rotated 180 degrees and surveyed again; the difference is twice the shaft offset. If the target is placed at two axial locations and measured for offset, the difference in the offsets divided by twice the axial separation is the angular error in radians. The figure below shows a typical method to measure shaft alignment errors using a laser and target. [pic] A more sophisticated alignment application is to sweep a laser beam quickly to generate a plane of light. The advantage of this is that many targets can be aligned using one laser source. In simple straightness applications the target location is restricted to the active area of the position sensor. In swept plane alignment, the targets are using sensitive in only one dimension. A typical application to establish a level plane is to put three or more targets at the same (desired) waterline location and adjust the structure the targets are on until all targets read the same. The targets for swept plane alignment can be static, meaning they require the laser beam to be directed in to them constantly. Usually the laser beam is swept by hand by rotating a knob on the laser source. If the laser plane is moving at high speed, say once a second or faster, then the targets must capture and hold the position of the laser beam as the beam sweeps by. The problem becomes harder to accomplish at longer distance because the beam is on the detector for such a short periods of time. The figure below shows a horizontally swept level laser beam scanning by several targets placed on a machine bed.

News Summary and Reaction :: Summary and Response

News Summary and Reaction ASTRONOMY â€Å"A New Black Hole† â€Å"Scientific American Evidence that the heavens house a previously unknown type of black hole was reported by scientists yesterday. Data from NASA’s Chandra X-Ray Observatory revealed a hole was some 600 light-years from the center of the starburst galaxy M82. The brightness of the x-ray source indicates that this moon-size hole has the mass of at least 500 suns, making it intermediate between stellar black holes and the supermassive black holes found at the centers of galaxies. â€Å"This opens a whole new field of research,† said Martin Ward, a lead author on one of three papers to be published on the subject. â€Å"No one was sure that such black holes existed, especially outside the centers of galaxies.† Earlier data from the Roentgen Satellite and the Advanced Satellite for Cosmology and Astrophysics had suggested that M82 might contain a large black hole outside its nucleus, but the Chandra results seal the deal. The new object might have resulted from the collapse of a â€Å"hyperstar† or the growth of a smaller black hole through mergers with others nearby. --Kate Wong Summary   Ã‚  Ã‚  Ã‚  Ã‚  A new unknown type of black hole was discovered on September 12, 2000. It was found to be 600 light-years of the Starburst Galaxy M82. An x-ray source indicates that the moon-size black hole has the mass of at least 500 suns, â€Å"making it intermediate between stellar black holes and the supermassive black holes found at the center of galaxies† (Scientific America, 1). Scientists were shocked at this discovery, for they didn’t know that these types of black holes existed. Scientists believe this black hole may have been due to a collapsed â€Å"hyperstar† or the growth of a smaller black hole through mergers with others nearby. Reaction   Ã‚  Ã‚  Ã‚  Ã‚  I find this so very fascinating because I can not even fathom how space and galaxies exist. With newer and faster technology, come new discoveries, and I think it’s great that we have the chance to explore a whole new frontier unlike the one we live on. I am in awe of what is possible today through the means of such a technologically advanced society. To know that people are able to leave our earth completely, in search of bigger and better things, utterly blows my mind. The Future   Ã‚  Ã‚  Ã‚  Ã‚  Through our discoveries we uncover more and are able to advance due to the information that we accumulate. Our work and discoveries lead to new inventions, which in turn change our lifestyle.

Of Mice and Men Essay

The book Of Mice and Men focuses on the friendship of two migrant workers in California at a time when most of the work was done by people and not by machines. George was a small man who acted worldly and wise. Lennie was a huge man that had the mind of a child. Together George and Lennie would bounce from job to job with no money in their pockets and only the dream of someday owning a place of their own to keep them going. The two men were not able to stay in one place too long because Lennie would get into trouble and George would have to get the two of them out of the bad situation and find a new place to work until the next bad thing would happen. Why would George continue to complicate his life by dragging Lennie around? Why wouldn’t George just set off on his own and make his life a whole lot easier? It was obvious when I read through the book that Lennie could not have survived in the world without somebody like George watching out for him. As the story unfolded I had to ask myself, â€Å"Did George need Lennie as much as Lennie needed George? † Two men traveling together the way George and Lennie did was not very common during this time. Slim said to George on page 39, â€Å"Hardly none of the guys ever travel together. I hardly never seen two guys travel together. You know how hands are, they just come in and get their bunk and work a month, and then they quit and go out alone. Never seem to give a damn about nobody. † Why did George and Lennie travel together then? It is easy to answer that question when looking at it from Lennies point of view. Lennie needed somebody to protect him. Lennie had the mind of a small child and would not have been able to find work, feed himself or stay out of trouble if not for somebody like George. The reason why George traveled with Lennie on the other hand is a little bit more complicated. One reason may have been George made a promise to the person who took care of Lennie before George that he would. Does this mean that George is such a stand up person that he would not go back on his word? Maybe but I don’t think it is the main reason he put up with Lennie and all the trouble that came with him. Another reason George may have kept Lennie around was that Lennie was such a great worker that it made George’s life much easier always working alongside of him. A third reason why George may have continued to travel with Lennie was that George liked the fact that he was in charge of Lennie, similar to how a father was in charge of what his son does. George had so little in his life that maybe having Lennie around to tell what to do all the time made him feel needed or important. Jus’ tell Lennie what to do an’ he’ll do it if it don’t take no figuring. He can’t think of nothing to do himself, but he sure can take orders† George tells Slim on page 39. A fourth reason George kept Lennie around is maybe Lennie made George feel smart. George seemed like the kind of person that liked to feel he was smart. The last reason I can think of and probably the biggest reason was that George needed the company. I don’t think that George could even imagine living how he lived and not having anybody to share anything with, including his ideas and his dreams. Ultimately, I think all of these reasons played some role in why George kept Lenny around but fear of being alone was probably the biggest reason. Something good is gained by both parties in every successful relationship and the relationship that George and Lenny have was no exception. Lenny of course received protection and a person to take care of him. Those are two things he could not have survived without. I think what George gained most from the relationship was becoming a better person. On page 41, George says to Slim, â€Å"I ain’t got no people. I seen guys that go around on the ranches alone. That ain’t no good. They get wantin’ to fight all the time. † George meant he didn’t have any family at all. George was afraid if he lost Lennie, he would never have somebody close to him again, he would be all alone and turn mean. That is what George got most out of the relationship, the friendship he believed made him a better person. I think George proved just how much he cared about Lennie at the end of the story when he shot Lennie in the back of the head by the creek. George made the ultimate sacrifice in killing Lennie and putting himself in the position that he feared the most which is being along. George knew if anybody else found Lennie, especially Curley, they would have made Lennie suffer to pay for killing Curley’s wife. It was interesting what happened earlier with Old Candy and his dog being put to sleep. Old Candy seemed just as upset about not shooting the dog himself as losing the dog. â€Å"I should have done it myself†, Old Candy said near the end of the book. Maybe George learned from that. George believed the right thing was for somebody who cared about Lennie to end his life no matter how much it hurt. Of Mice and Men is a book about relationships with the relationship between two very different people, George and Lennie, at the forefront. Early on it seemed very obvious that Lennie got the most benefit from their friendship. As the story unfolds, it’s not so obvious. In the end, I believe that George benefitted as much or even more than Lennie from their strange friendship. George believed that Lennie made him a better person.