Overview of the Last Glaciation

When did the last Ice Age occur? The worlds most recent glacial period began about 110,000 years ago and ended around 12,500 years ago. The maximum extent of this glacial period was the Last Glacial Maximum (LGM) and it occurred around 20,000 years ago. Although the Pleistocene Epoch experienced many cycles of glacials and interglacials (the warmer periods between the colder glacial climates), the last glacial period is the most heavily studied and best-known portion of the worlds current ice age, especially with regard to North America and northern Europe. The Geography of the Last Glacial Period At the time of the LGM (map of glaciation), approximately 10 million square miles (~ 26 million square kilometers) of the earth was covered by ice. During this time, Iceland was completely covered as was much of the area south of it as far as the British Isles. In addition, northern Europe was covered as far south as Germany and Poland. In North America, all of Canada and portions of the United States were covered by ice sheets as far south as the Missouri and Ohio Rivers. The Southern Hemisphere experienced the glaciation with the Patagonian Ice Sheet that covered Chile and much of Argentina and Africa and portions of the Middle East and Southeast Asia experienced significant mountain glaciation. Because the ice sheets and mountain glaciers covered so much of the world, local names have been given to the various glaciations around the  world. The Pinedale or Fraser in the North American Rocky Mountains, Greenland, the Devensian in the British Isles, the Weichsel in Northern Europe and Scandinavia, and the Antarctic glaciations are some of the names given to such areas. Wisconsin in North America is one of the more famous and well-studied, as is the Wà ¼rm glaciation of the European Alps. Glacial Climate and Sea Level The North American and European ice sheets of the last glaciation began forming after a prolonged cold stage with increased precipitation (mostly snow in this case) took place. Once the ice sheets began forming, the cold landscape altered typical weather patterns by creating their own air masses. The new weather patterns that developed reinforced the initial weather that created them, plunging the various areas into a cold glacial period. The warmer portions of the globe also experienced a change in climate due to glaciation in that most of them became cooler but drier. For example, rainforest cover in West Africa was reduced and replaced by tropical grasslands because of a lack of rain. At the same time, most of the worlds deserts expanded as they became drier. The American Southwest, Afghanistan, and Iran are exceptions to this rule however as they became wetter once a shift in their airflow patterns took place. Finally, as the last glacial period progressed leading up to the LGM, sea levels worldwide dropped as water became stored in the ice sheets covering the world’s continents. Sea levels went down about 164 feet (50 meters) in 1,000 years. These levels then stayed relatively constant until the ice sheets began to melt toward the end of the glacial period. Flora and Fauna During the last glaciation, shifts in climate altered the world’s vegetation patterns from what they had been prior to the formation of the ice sheets. However, the types of vegetation present during the glaciation are similar to those found today. Many such trees, mosses, flowering plants, insects, birds, shelled mollusks, and mammals are examples. Some mammals also went extinct around the world during this time but it is clear that they did live during the last glacial period. Mammoths, mastodons, long-horned bison, saber-toothed cats, and giant ground sloths are among these. Human history also began in the Pleistocene and we were heavily impacted by the last glaciation. Most importantly, the drop in sea level aided in our movement from Asia into North America as the landmass connecting the two areas in Alaskas Bering Strait (Beringia) surfaced to act as a bridge between the areas. Todays Remnants of the Last Glaciation Though the last glaciation ended about 12,500 years ago, remnants of this climatic episode are common around the world today. For example, increased precipitation in North Americas Great Basin area created enormous lakes (map of lakes) in a normally dry area. Lake Bonneville was one and once covered most of what is today Utah.​ The  Great Salt Lake is todays largest remaining portion of Lake Bonneville but the old shorelines of the lake can be seen on the mountains around Salt Lake City. Various landforms also exist around the world because of the enormous power of moving glaciers and ice sheets. In Canadas Manitoba for instance, numerous small lakes dot the landscape. These were formed as the moving ice sheet gouged out the land beneath it. Over time, the depressions formed filled with water creating kettle lakes. Finally, there are many glaciers still present around the world today and they are some of the most famous remnants of the last glaciation. Most ice today is located in Antarctica and Greenland but some ice is also found in Canada, Alaska, California, Asia, and New Zealand. Most impressively though are the glaciers still found in the equatorial regions like South Americas Andes Mountains and Mount Kilimanjaro in Africa. Most of the worlds glaciers are famous today however for their significant retreats in recent years. Such a retreat represents a new shift in the earth’s climate—something that has happened time and time again over the earths 4.6 billion year history and will no doubt continue to do in the future.

Fate And Freewill Are Spiritual Aspects That Explain Human

Fate and freewill are spiritual aspects that explain human outcomes. The tragic story of Dr. Faustus almost divides the readers spiritual opinion on freewill and predestination. While free will and predestination may be complex themes to comprehend, Marlowe flawlessly shows how Faustus’ actions and mindset portray both aspects. Marlowe presents Faustus spiritual struggles while simultaneously explaining life and the choices people make. Humans are free to make mistakes and fully choose how their life unfolds. However, free will is greatly clouded by cause and effect (Strong 7). The play questions the constraints of free will and fate, and the ambiguous nature of both aspects (Manley 219). As Faustus opens up the play he inspects what he†¦show more content†¦Arguably, it could been seen as Faustus lacking the ability of choice because his life is predetermined. Faustus is so inconsistent with any choices he makes it is hard to believe that such a smart man could be so naive. Faustus feels people’s lives are set in stone. This is clear when he reads a verse from The New Testament: â€Å"Why, then, belike we must sin And so consequently die. Ay, we must die an everlasting death. What doctrine call you this? Che serà  , serà  ? What will be, shall be? Divinity, adieu!† (I.i.42-46) This exert clearly shows that Faustus truly believes that he does not control his life. Faustus feels that no matter what actions he does, it does not determine if he will go to heaven. Faustus thinks he is already eternally damned. Ironically he also does not read the whole verse. Instead he creates his own version of Jerome’s Bible. How could such a knowledgable man misinterpret verse? Perhaps he was destined to read it wrong to cement his belief in being predetermined. Faustus is free equally doomed by his manhood and his choices (Manley 219) As Faustus progresses over the play the reader can see that he is somewhat regretful. Briefly Faustus even contemplates being able to save himself from damnation: â€Å"Now, Faustus, must thou needs be damned? Canst thou not be saved? What boots it, then, to think on God or heaven? Away withShow MoreRelatedEssay on War and Peace and Tolstoys View of History2791 Words   |  12 Pagesin the novel reflect his theory of history, Tolstoy iterates this in less narrative terms in the twelve chapters of the Second Epilogue, described as, A general discussion on the historians study of human life, and on the difficulty of defining the forces that move nations.   The problem of freewill and necessity.   The view of history explored by Tolstoy has had few sympathisers and copious critics.   Tolstoy predicts this disagreement earlier in War and Peace in his description of the life of a

Impressionism vs. Mexican Muralism Free Essays

Impressionism vs.. Mexican Muralist As we all know, cultures and events shaped the world were being mirrored in the world of art. We will write a custom essay sample on Impressionism vs. Mexican Muralism or any similar topic only for you Order Now From Impressionism to Mexican Muralist, art has experienced lots of movements and it is easy to get confused regarding the similarities and difference between Impressionism and Mexican Muralist. In this essay, I will clear those things from two paintings: Camille Pissarro Boulevard Montmartre (Afternoon, Sunshine) and Diego River’s A Dream off Sunday Afternoon in Alameda Park. The two images above are excellent examples of different styles of the Impressionism and Mexican Muralist. While the content is relatively similar, such as natural background, bright color, and even both of them depicted a scene happened in the afternoon, the feeling of the two paintings is remarkably diverse. The painting Boulevard Montmartre has a much softer edges and low-tone feel too it, compared to the stark contrast of A Dream of a Sunday Afternoon in Alameda Park with its clear boundaries and striking use of color. Actually, besides the optical effect, Mexican muralist also aimed at conveying social and political messages to the public. Impressionism which can be noninsured as the first obviously modern movement in the art occurred from 1860 to 1890 in France, and its effects have spread well beyond Europe and eventually the United States. Its sponsors who against Academic des Beaux-Arts, which predominated the French art scene at that time, were accordingly rejected to exhibit their art works in Salon des Paris, such as works from Meant, Monet and so forth(Lana Barras Hill 119). Instead of portray likenesses that mirrored a subject in as much as detail as possible, Impressionism artists focus on natural light and intend to capture the fleeting movement in an instant time. In order to perform this effect vividly, they moved from the studio to outdoors. One of the representative works which can reflected this style is Boulevard Montmartre, a series paintings drawn by Camille Pissarro in early 1897. â€Å"Pissarro was looked upon as the father of the impressionism group, and he was the only painter to exhibit at every one of the eight Impressionist exhibitions† (Ian Barras Hill 135). Pissarro was inspired to paint outdoors. As a freer handling of brighter colors, he always applied colors softly and his talent clearly lay in the reality of nature in landscapes with figures. After spending six years painting for rural setting, he returned to Paris and rented a room at the Grand Hotel De Russia in Paris in order to have a perfect view and unusual angle of the intersection of the Montmartre Boulevard† (Anne Gray 16). Boulevard Montmartre, afternoon, sunshine is an extraordinarily energetic painting of the fourteen painting series, which displays a fasting moving and dynamic urban life in Paris during the working hours of the day. Since he is looking out the left of his bedroom window, his eyesight was falling and the vanishing point is higher. As a exult, the strong central shape of the receding boulevard, flanked by rows of trees, street-level shops and impressive apartments, dictates the open, powerful composition and high perspective. Rapid, thick brush strokes used on the sky and road draw the eye down this thoroughfare, which has crowds and heavy traffic. Like the blurred photos, figures, commissaries and omnibuses in this painting hold no discernible details. Pissarro captures a bustling movement in an instant time and just rough sketches of them. Of course, a broad pointillism is also used in many places, such on a road surface. In addition, the scene is presented with a palette of great subtlety and colors are applied side-by-side with mixing creating a vibrant atmosphere: grey, browns and whites accented with red and tiny amounts of green. Certainly, softly edges between pedestrians and background produced by Pissarro makes the color much more natural. Abbreviation depicted the subject matter imply that the Impressionism artist emphasizes on capturing the essence of the subject. Besides, Pissarro still focus on the changing natural light and weather effects, and the figures under the sunlight which contrasts the shadow, dark Cambridge and looting convey the rich atmosphere effect. Nevertheless, Mexican Muralist which prevails specifically during the ass’s and ass’s is extremely different from Impressionism. The three main and most important artists during this movement were Jose Clement Rocco, Diego Riviera, and David Alfalfa Queries, and the muralists in Mexico were interested in Aztec and Amman cultures, depicted some Mexican people and their heroes’ live and work. During the early years of the twentieth century, those three representative muralists who were influenced by the European modernist art returned to Mexico and began to paint and teach. Dorothy Chaplin 26). In contrast to Impressionism, Mexican Muralist movement is not only an artistic movement but also a social and political movement. In fact, the mural styles by Mexican Muralist artists were regarded as a teaching method, aimed at convey social and political messages to the public regardless of race and social class. Among the three Mexican muralists, Diego Riviera who were good at large wall works in fresco is the most prominent and controversial artist in Mexico. Riviera developed his own native painting style that was also social realism. Under the influence form Aztec, he was skilled in applying bold and vivid colors to paint Mexican peasant or large simplified figures. (Ivory Davies 38). River’s mural A Dream of a Sunday Afternoon in Alameda Park which is a fifty foot fresco takes the viewer on a Sunday walk through Alameda Park. It was painted on a wall of the Hotel Paradox in 1947. Minion, an earthquake destroyed hotel, but the mural, perhaps the best known of River’s works was relocated to a new museum across the street (Renee Pamela 8). † The painter presents people and events in Mexican history from cotes, the emperor Macmillan, the revolutionaries Million Capita and Francisco Madder, to his own day’ (R Hagen 101). Portrayed in the mural are numerous historical figures, more or less from left to right, but not in chronological order. Specifically, Diego Riviera in this mural depicted as a child holding the hand of a fashionably dressed skeleton figure, the omnipresence of death in the everyday life of Mexico. The figure standing maternally beside him is his wife, who is a self- portrait artist and feminist icon in Mexico and parade around them is impervious rich and unrequited poor. Unlike the repose for capturing the transient quality of life in impressionism, River’s painting intends to present a universal political dream in Mexico and covey some social and political message to the public. As in the Dream of a Sunday Afternoon in Alameda Park, this is no class martyrdom and colonial tragedy. The message of Dream of Sunday is accusation of the tension of the violent matter. Besides, he also combined historical and allegorical imagery. Actually, balloons on the background represent the strife for Mexican Liberty. As previous stated, there are more than a hundred satirical figures in this mural. Unlike pedestrians with rough sketches in the Boulevard Montmartre, Riviera cataloged social types from ruler to the bottom of the society, costumes, adornments artifacts, animals, and plant. This mural is a descriptive and documentary painting, which carried to utmost limits of crowded detail and illustrative functionalism (Gilbert Chase 11). In turning away from softly edges and rough sketches which impressionism artists of their day aspired, Riviera chose a realism to convey that subject matter through this fresco. What’s more, Riviera was mastery of sense of composition, space and striking use of color. Instead of dark clothes and commissaries in Boulevard Montmartre, people from different classes wear brightly colorful costumes. Furthermore, the bright yellow and purple applied in the tree or sky stands in sharp contrast to the grey and brown sky in Boulevard Montmartre. In conclusion, River’s artistic masterpieces were a collection of many European styles. Although Mexico Muralist inspired by the painting technique of impressionism, artists during Mexican Muralist began to realize all this innovation ad little to do with real life. As a result, in order to convey political and social messages to the vast number of uneducated people, Riviera chose a traditional art form and style to present the new subject matter (Gilbert Chase 12). Got away from focusing solely on optical painting in Impressionism, Mexican Muralist artists who began to carry a clearly discernible social and political comment in their artworks creates a new era in the human art treasure. Works Cited Anne Gray. Incubi: last impressions 1907-17: National Gallery of Australia. Seep. 2009. Print. Dorothy Chaplin. How to cite Impressionism vs. Mexican Muralism, Papers

Acute Respiratory Tract Infections Biology Essay Example For Students

Acute Respiratory Tract Infections Biology Essay Acute respiratory piece of land infections play a major function in hospitalizations of kids, and respiratory syncytial virus is good recognized as the most of import pathogen doing ARTI.Objectives: This survey aimed to measure epidemiological and clinical forms of RSV infection in kids hospitalized for lower ARTI in Ahvaz, Iran. Patient and Methods: Respiratory specimens collected from 100 kids with lower ARTI from October 2008 until the terminal of April 2009, were screened for RSV utilizing real-time rearward transcription-polymerase concatenation reaction ( RT-PCR ) . Consequences: During the survey period, 9 kids had a positive consequence for RSV infection. The average age of these patients was 10 months. Bronchiolitis was the clinical diagnosing of patients with RSV infections. All of these patients were less than 24 months. Cough ( 77.7 % ) and chest wall abjuration ( 100 % ) were the taking symptoms and marks respectively.Conclusions: This survey indicates that RSV is an of import cause of respiratory tract infection in babies less than 2 old ages old. RT-PCR offers a rapid method for common respiratory viruses. Cardinal words: Children, lower respiratory tract infection, Respiratory syncytial virus, Rt-PCR. 3 1.Background Acute respiratory piece of land infections ( ARTIs ) are a prima cause of hospitalization and mortality in kids less than 5 old ages of age and stand for a considerable wellness job in the universe. ( 1 ) Viruss, including respiratory syncytial virus ( RSV ) , metapneumovirus, influenza A and B, parainfluenza and adenovirus are the most common aetiologic agents for childhood acute respiratory piece of land unwellness. ( 2 ) Among viral causes of acute respiratory piece of land infections, RSV has a important function. Human respiratory syncytial virus is an enveloped, single-stranded ; negative- sense RNA virus of the genus Pneumovirus.The extremum incidence of the RSV infections is between the 2nd and six month of age. It can do important morbidity from upper respiratory infections, acute bronchiolitis, and bronchial pneumonia to apnea in kids. ( 3, 4 ) In hospitalized kids, RSV infections occur at greater frequence than other viral infections of the lower respiratory piece of land. It is identified as the etiologic agent in 60-90 % of the patients with bronchiolitis and in 25-50 % of the pneumonia. ( 5, 6 ) In temperate states, RSV eruptions have a defined seasonality, happening chiefly autumn and winter while in tropical and semi-tropical states, it chiefly peaks during the rainy season. ( 7, 8 ) In add-on to conventional viral civilization techniques and serology, a late described advanced, polymerase concatenation reaction ( PCR ) for the diagnosing of respiratory viral infections has besides been shown to be utile because it offers an enhanced sensitiveness combined with rapid sensing. Even if certain viruses such as RSV can be grown in cell civilizations, this method is non 4 wholly dependable and many scientists have begun to utilize real-time polymerase concatenation reaction RT-PCR to place infections. ( 9,10 ) Information on the epidemiology of RSV infections in developing states are still limited. The most of these surveies have non used extremely sensitive molecular techniques such as ( RT-PCR ) . ( 11-13 ) 2.Objectives The intent of this survey was to supply informations about the sensing of RSV by RT-PCR in hospitalized kids up to age of five old ages in Ahvaz, Iran. 3.Patients and Methods The survey population consisted of kids less than 5 twelvemonth of age, admitted in the Aboozar kids s infirmary with lower respiratory tract infections ( LRTI ) . It was designed to inscribe topics from the beginning of October 2008 until the terminal of April 2009.Newborn babies less than 28 yearss were excluded.LRTI were categorized on the footing of clinical and roentgenographic findings as pneumonia and bronchiolitis. Bronchiolitis was defined as an acute respiratory unwellness characterized by rhinorrhea, cough, and dyspnoea and diffuses wheezing, with peribronchial thickener and hyperexpansion on thorax radiogram if available. Pneumonia was defined as dyspnoea in a patient with focal rattles or decreased eupneic sounds and the presence of a focal infiltrate and/ or consolidation on thorax radiograph.5 During hospitalization, the kids s marks and symptoms were obtained by a reappraisal of medical charts. This information was reviewed and entered into a database. Informed consent was Nature by Ralph Waldo Emerson EssayOther surveies from Iran have showed incidences of RSV infection 12.9 % , 15 % , 16.8 % in instances of LRTI and all of these studies are from temperate parts. ( 20-22 ) The difference of RSV epidemiology in the universe may be related to differences in clime conditions, in environmental factors and in badness of its epidemics from one twelvemonth to another. ( 10 ) It has reported negative correlativities between higher monthly mean temperature and RSV infection in tropical parts. 21 Ahvaz is in the sou-west of Iran and has fall-winter seasons characterized by comparatively warm non prefering the endurance and the spreading of RSV.8 Studies have shown that some paediatric patients with acute lower respiratory tract infection become infected at the same time with multiple respiratory viruses. Dan peng et Al suggests that there is a high happening of multipathogen infections in kids admitted withacute respiratory piece of land infections and that coinfection is associated with certain pathogens. In this survey RSV was detected in merely 5.7 % of instances. ( 23 ) In add-on, Arabpour et al reported high prevalence ( 54.4 % ) of Human metapneumovirus ( hMPV ) , among Ahvazian kids with respiratory piece of land infections. This survey showed the likely function of hMPV as an of import causative agent of acute respiratory piece of land infections in this country. ( 24 ) In our study, there was a somewhat higher incidence of RSV infection in males ( 1.3:1 ) .This consequence was consistent with other surveies. Sangar et al suggested that being female was protective against RSV hospitalization. ( 25,26 ) In this survey all of the kids that tested positive for RSV had bronchiolitis and the highest figure of positive samples for RSV is in the patients less than 1 year.This inclination toward younger age in RSV infections has been reported in other reported informations. ( 27,28 ) The clinical characteristics of kids with RSV positive samples observed in our survey were similar to those of old studies. ( 14, 15 ) There were two major restrictions in our survey. One of our restriction is though some kids presented the standards for inclusion in this survey, samples from 100 patients were collected, due to the bound established for processing and storage of samples. The 2nd restriction is we did non look into out all of the respiratory viral agents in our patients. It seems in 9 our geographic place and clime state of affairs the other viruses like hMPV have an of import function in LRTI in children.Infections with respiratory viruses are a common cause of morbidity and mortality around the universe. A better apprehension of the epidemiology of respiratory viral infections may be used for seasonably, specific antiviral therapy, prophylaxis, and inoculation. Future prospective surveillance over an drawn-out period in this part is needed to accurately place the epidemiology of viruses.