Monday, January 27, 2020

The Co2 Life Cycle Of A Printer Environmental Sciences Essay

The Co2 Life Cycle Of A Printer Environmental Sciences Essay The report provides information about the life cycle inventory of a printer used domestically as a peripheral of personal computer. The purpose of the study is to evaluate various stages in the life cycle of a printer from its production to the end of life and flow of various materials and the production of CO2. The life cycle of printer has been investigated with help from literature research, industrial statistical data and information from various manufacturers. The approach has been adopted with much assumption for simplicity. The current study encircles life cycle changes starting from the manufacture of printer to the end of life. The raw material used in manufacturing, production of solid waste, effluents into air and water, paper use, the electricity used, and the use of cartridges are all measure according to rough estimates. However, the proportion of electricity used in printer in whole life cycle only makes 14% of the printer weight. However, the electronics used make a s ignificant part in the green house gas due to the presence of copper. Therefore, an improved and better estimate of perfect life cycle may be possible if real statistical data is available instead of making assumptions. Local manufacturing, recycling, refilling and careful use will be helpful to reduce environmental impact. The LCA of various types of printers will be valuable information for engineers to re-design future printers that are more environmentally friendly (Curran 1996). The current study also elaborates the importance of conducting LCA of a product. Global warming, environmental pollution, industrial reforms to manage environmental pollution and human efforts to control global warming are hot issues now-a-days (Curran 1996). Every product has a life cycle starting from its manufacturing to its end of life (Lehman 2007). The life cycle assessment (LCA) is a significant tool to assess the impact of a product on environment throughout its life (Hischier 2007). Mechanical and manufacturing engineers can take benefit of LCA data of a product to review and revise the material, design and technology of the product to reduce its negative impact on the environment (Fussler et al 1996). With the information of LCA of the products, it is possible to select environmentally friendly material to make products pleasant, less harmful to environment and more efficient (Guinee 2001). Cost has been a significant incentive but information of global warming has changed businessman and buyers view about a product (Newton 1993). Both buyer and busines s man is more attractive to environmentally friendly product (Cramer et al 1997). Use of computers in modern era has created a lot of peripheral and accessories used parallel to the computers. Printers, scanners, web cam and many other accessories are everyday use in modern era. Each of these products is made of various materials and therefore has various stages of life cycle. The current study is limited to the Life cycle Inventory Analysis of a printer. An Inventory analysis is not complete analysis of life cycle but still provides basic information about the product interaction with the environment. The Inventory life cycle analysis does not provide the full picture of the environmental impacts of product. A true LCA or absolute inventory LCA is possible where all statistical data is available from the manufacturing till the life end of product with its disposal stage. The printers are of various types. Major classification of printers fall under dot matrix printers, ink jet printers and laser printers. According to manufacture and distribution companys statistical data, there is 60% printer waste from USA and 40 % form European countries (HP 2009). However, other Asian countries and the rest of the World should not be ignored as there is ever growing demand of IT products throughout the world. Printers are manufactured in Malaysia, China, Japan, Asia, Europe, and USA and in many other countries. Taking China and Malaysia as major manufacturer of printers, the ocean freight distance to Europe and USA, material extraction assumed at miles away and parts manufacturing and transporting from long distance may contribute to the impact of printers life cycle. The developed countries like USA and European Union countries have monitoring bodies like Environmental protection Agencies to monitor the safe disposal of various products. The printers are supplie d in packaging mostly made of card board. The card board packaging is reused at most of sites according to local policies but variation in percentage is present. In USA about 60 % packaging is recycled (MPCA 2009). The printers are used domestically, commercially and in industry. We are using small domestically used printer in our case study. The general purpose of domestically used printers is designed to do a satisfied job of printing at acceptable perfection level. Normally, no duplexer is associated with domestically used printers and pages are turned manually by the user. Mostly two types of cartridges are used; one for the text printing and other for the color printing. A printer pack usually comes with a printer itself, a black cartridge, a color cartridge, a power cable, an external power supply, a USB or other port connecting cable, CD-ROM (with software) and a user information booklet. The printer varies in size and normally weighs range from 1.5 to 5 kg. Similarly the price varies according to make and quality. Now we can take an analysis of printers manufacturing stage. Printers are made of polymers in their primary structure and in the manufacture of its parts (Smits 1996). Two most commonly polymers in printers include high impact polystyrene (HIPS) and acrylonitrile-butadiene styrene (ABS). However, all plastics in printers are not necessarily HIPS or ABS and 86% of plastic in printers are recyclable (William et al 2002). An excluding percentage is not recyclable due to the presence of fillets. However, for the simplicity of our case study, we assume that printer plastics are ABS. We will be considering main manufacturing material in life cycle and will not focus on the intermediate material processing, packaging and shipping. A table for packaging material inventory has been reprocessed from information sources (Jason et al 2005). Various metals are used in printers manufacturing. The metals include galvanized steel metal for structure, plated steel shafts, and Copper metal in motor and small fraction of Aluminum in other parts. These metal materials are recyclable but Copper in motor may inhibit steel recycling. The electronic component also contributes to environmental impact and consists mainly on printed electronic board (PWB) and some electronics. However, the electronic components only make the 3% weight of the printers in total (William et al 2005). The electronics in printers consist on few PWB; usually six and weighing about 250 grams. The circuit boards are made of few mm thick epoxy coated glass fiber cloth laminate plated with copper but these are free of lead. The process of circuit board manufacturing consists on FR4 laminate process; a complex and popular laminate substrate manufacture process. The process is a wet processing method consisting on masking, lithography, plating, and electronics im planting to create a printed circuit board. The epoxy is usually mixed with a bromide flame retardant. The standard FR4 boards are one ounce or two ounce copper type depending upon the amount of Copper per square foot used in their manufacturing. The residual Copper is stripped away from the circuit board once print has been developed. The average weight of circuit board weighs about 10-15 grams depending upon the size of the board. About eight liter of water is used in the manufacture of a printers boards (Industry information). The soldering material is used to mount electronic components on circuit boards (Lehman 2007). According to manufacturer information, the soldering material required to manufacture a printers board amount about 0.000202446 KWh/Cm2 of PWB (HP 2009). However, it is calculation for lead free solder and VOC free flux which is environmentally friendly and require more energy requirement. Connecting wires and cables in printer also contain Copper (average less th an 100 grams). Normally more than sixteen semiconductors are used in printers. These are mostly made of plastic (HP 2009). The LCA of a printer has been outlined in figure (12) starting from its manufacture to the end of life. The life cycle of the printer defines the material and energy associated with the printer over its life cycle from the extraction, collection of the raw material at production site, production process, its use, reuse, recycling or disposal at the end of life and its contribution in the global carbon foot print. In a real sense, the LCA of printer is an analysis of the material and energy flow till the end of product life. The packaging and shipping of printers also contribute to the carbon print and make a contribution in their life cycle (Hischier 2007). The packaging consists on cardboard box, paperboard, and paper manual and polystyrene restraints (PEPI 2008). There may be strips of paper cuttings as been used to secure printer packaging in the past. Shipping and transportation of printer also contribute in the carbon print of the global warming. Figure 1; LCA Figure 2; Printer Life Cycle phases In our assignment we assume that printers are manufactured in China and distributed all over the world. The environmental impact of a printer may be classified into phases. The primary phases of paper use, ink cartridges and electricity and waste products are contributory to the LCA of a printer. The printers use paper, ink and electricity through out of their life cycle. The cartridges consist on polyethylene Terephthalate (PET) glass filled polyester and electronics. Mostly, LCA of a product is focused to find out impact on carbon foot printing (Guinee 2001). According to a research conducted by HP on its inkjet printer LCA, paper has a significant contribution in carbon foot printing (HP 2009). Contribution to carbon foot printing is a global terminology to find out environmental impact of a product during its lifecycle (Fussler 1996). An inventory table has been reprocessed by taking information from two resources (See table 1for printer and table 2 3 for Cartridge and packaging) . Item Mass(Grams) Note Metals(Total) 910 Steel 696 Aluminum 165 Copper 49 Motor Winding Plastic(Total) 2179 Recyclable 1887 Non-Recyclable 292 ABS 163 HIPS 1472 Others plastics 544 Includes elastomers etc Others Genera 144 Electronics(Total) 507 Including external cable and power supply. Printer Total 3740 Recyclable(Total) 2947 Includes recyclable metals, plastics, copper etc. Recyclable (%) 79% Table 1 (Inventory table reproduced by information sourced Jason et al 2005; William et al 2002) Ratio between recyclable and non-recyclable material in an inkjet printer Figure 3; Comparison between recycleable and non-recycable material Inventory table reproduced by information sourced Jason et al 2005; William et al 2002 Cartridge Material Item Mass (gram) Note Plastics(total) 20 PET+ 15% GF 20 Other Plastics Other Generals(total) Electronics 4 Ink 21 Black 21 g/Color 42 g Cartridge Total 45 Table 2 (Jason et al 2005; William et al 2002) Printer Packaging Table 3 Printer Packaging Item Mass(gram) Note Polystyrene 0.014 Shipping restrain Polycarbonate 0.015 CD Paperboard/Cardboard 0.881 Office paper 0.107 Manual etc Packaging(Total) 1.017 Table 3 Jason et al 2005; William et al 2002) We can describe the impact of printer by dividing it into three phases; paper usage impacts, electricity usage and the management of waste products. According to historical data, the usage of paper has increased to three fold over the last three decades (Mckinny 1995). The paper has been used as a main source of information storage since ancient Egyptians invented the papyrus, the Chinese make it more perfect by large scale paper manufacture and Gutenberg invented the printing press (Saaty 1980). However, the global warming has increased the importance of paperless terminology and most of organizations and utility firms are switching to the paperless strategies (Newton 1993). There are three significant way to assess the environmental impact of a product (James 1997). These are known as eco-point, eco-cost and eco-compass. In life cycle environmental cost analysis (LCECA), the eco costs are included into the total cost of the product. The eco-cost are the sum of direct and in-direct costs of the environmental impacts caused by the product in its entire life cycle. The aim of the LCECA is to find out alternative design, model and parts which are eco-friendly. Actually, it is true analysis as impacts on environment does cost us like waste management or the health hazards to the public etc. In our example of the Ink jet printer, we can add the cost of health hazards of ink, disposal cost and use of electricity in the actual cost of the printer to find out the LCECA. For example an inkjet printer may be cheap at its initial price than other printer but may cost more on the basis of its environmental impacts than other printer which are expensive at the beginning but is energy efficient and less negative to the environment. Energy efficient product is environmentally friendly as it produces less carbon print (NUON 2009). The other system which is mostly used in UK is the eco point system to find out the environmental impacts of a product. A score is fixed for each impact of the product. Then the score are calculated and sum up to find out the resultant impact of a product. The score mentions the actual eco points of a product on the environment. UK eco point system is an established methodology and internationally accepted. The eco points are calculated from the LCA of a product. The process of eco point calculation is not very straight forward but not very complicated. The characterized data is found out in the form of units (e.g. climate, vapors etc) divided by the norm (UK impacts per person). Then it is multiplied by a weighting to convert into eco points. For example, if we want to assess the environmental impacts of our product; Ink jet printer, then we will calculate eco points for each impact se parately and then sum them up to make resultant eco point. The third method to find out the environmental impact is called as eco compass method. In this method the sustainability of the product design is assessed to assess the environmental impact of a product. A sustainable product design (SPD) is defined as the design which is economical, environmentally friendly and socially liked (Tassoul 1998). A SPD is not a simple design but it is an innovative, creative and efficient. It requires the efforts of various business sectors such as policy makers, business strategies, managers. A SPD can provide better positive impact on environment. For example, in case of our produce: Inkjet printer, A SPD may be a printer with least harmful ink, very efficient on energy consumption and with least waste material. The impact of printer usage on environment can be best understood by considering carbon print produced as a result of energy usage during its manufacture, use and then in waste disposal. All stages of printer should be considered starting from, printer manufacture to the end of printer life. None of the stages can be ignored as ignoring any phase will not count the actual amount of CO2 production at that stage. For example, if we ignore manufacturing stage then we can ignore the Co2 produced at manufacturing stage of the printer. The printers industrial, commercial or domestic use some chemicals in the form of ink which is harmful to the environment and human health (Dias 2004). These chemical are hepatotoxic, nephrotoxic and also cause significant damage to lungs, skin and nervous tissues if exposed for long time. The harmful materials used in printer also contain very hazadorous material including Silver, Phosphoric acid and Isopropyl alcohol. However, the things are changing now; the printing industry has started to look at less harmful solutions. One of such measures is the waterless printing. The waterless technology reduces VOCs (Volatile Organic Compound) emissions by 98 %. The VOC are the major contributor in formation of low level Ozone (Counsell et al 2007). The low level ozone can cause respiratory problems and aggravate asthma and other respiratory diseases. The VOC are gasses consisting on harmful chemicals with negative health effects. These chemicals cause environmental pollution by spreading p etroleum based ink dies (Erbes 1996). Petroleum based inks have been the traditional choice in the printing industry. These inks are not considered as environmentally friendly. The other disadvantages of petroleum based inks are the use of non-renewable resource-petroleum. There has been a revolution in ink improvement in print industry. These inks are vegetable based and soy based inks and release few fractions of VOC. Printers have environmental impacts which should be minimized. Socially we can adopt environmentally friendly behavior if we adopt certain attitudes towards the use of printers. First of all less paper can be used if double sided printing is used (UC 2009). Therefore, duplex printing should be preferred. Now-a-days, there is universal attitude to go paperless. A lot of options are available in the form of CDs, flash memory sticks, HDD and memory cards. An attitude to recycle cartridges may reduce waste and pollution. The trend has increased and most of manufacturers are accepting used cartridges for recycling. The used cartridges may be re-filled and reused. The manufacturers may be encouraged to manufacture such cartridges which can be used again by re-filling ink. The reuse and recycling of the cartridges may reduce the landfill by cartridge plastics and thus can save landfill and resources. Ink refills are also available in mega fill packs reducing the packaging and waste fill. In addition to saving on paper and cartridges, electricity is another consideration. Energy efficient printers with energy saving modes are available and should be used in preferable way. In short, the LCA of inkjet printer has provided enough information on environmental impacts of inkjet printer from manufacturing to the end of life and then disposal. The LCA of a printer has provided us enough information to review, revise and plan environmentally friendly design of a printer. It also indicates less harmful priorities and choices during life cycle of a printer. For example double sided printing will be environmentally friendly than single sided printing. Double amount of paper will be consumed in single sided printing. To use double sided printing mechanical design and/or software may need updating. Next consideration may be the nature of paper. Paper generated from wood pulp has much impact on environment (Szabo 2009). Therefore, paper generated from non-wood fibers should be used for better environmental effects (Abramovitz et al 1999). Again printer design may need to change to adapt non-wood paper use. The second major contributor of environmental impacts in LC A of a printer is the electricity. An automatic solution is saver mode where printer turns off automatically when it is not in use. However, the user should also adopt the habit of turning off printer when it is not in use. The act of turning off printer when not in use will save approximately half of the environmental impact caused by a cartridge during its life cycle (William et al 2002). In addition to that, printer which do not used electricity when in off mode should be promoted. The current study also suggested the use of vegetable origin ink cartridges to reduce environmental impact. Similarly saving paper and cardboard by multi-items pack will also help to reduce environmental impact. It would be better to mention life cycle costs on cartridge pack to convince user about environmental impacts of ink. At the end of product life, the reuse and recycling of various materials should be promoted. The selection of material at manufacturing stage becomes important as it may provide chance to select sustainable material that can be reused or recycled. References Counsell. T., Allwood.J.2007. Reducing climate change gas emissions by cutting out stages in the life cycle of office paper. Resources, Conservation and Recycling. (49)340-352. Dias.2004. Evolution of the environmental performance of printing and writing paper using life cycle assessment. Management of environmental Quality journal. (15)473-483. Hischier.R. 2007. Life cycle inventories of packagings and graphical papers. Dubendrof. Lehman.M.2007. Life cycle inventories of electric and electronic equipment. Dubendrof. Szabo, L.2009. A world model of the pulp and paper industry. Environmental Science and Policy (12)257-269.

Sunday, January 19, 2020

Marketing Management’s Ability to Develop Essay

Main Forces in the Organisation’s Macroenvironment Macroenvironment: The larger societal forces that affect the whole microenvironment. – The organisation and its microenvironment operate in a larg macroenvironment of forces that shape opportunities and pose threats to the organisation. The organisation must carefully watch and respond to these forces. The macro environment comprises of six main forces: 1. Demographic Forces: Demography is the study of human populations in terms size, density, location, age, sex, race, occupation and other statistics. The organisa my group discussed was McDonalds. The points we come up with involving demographic forces were:- As Australia has an aging population McDonalds co better tailor products this. – As Australia is and is becoming more ofa multi cult society McDonalds need to be aware of the ethnic diversity in each region. 2. Economic Forces: The economic environment consists of factors that affect consumer buying power and spending patterns. Markets require buying power a well as people. Total buying power depends on current income, prices, savings an credit. Marketers should be aware of major trends in income and changing consu spending patterns. A range of products to meet all levels of income would be advantageous especially considering the recent global financial crisis where consumer spending was dramatically reduced. 3. Natural Forces

Friday, January 10, 2020

Role of Ultrasound in the Early Detection of an Ectopic Pregnancy.

CASE STUDY: Role of Ultrasound in the early detection of an ectopic pregnancy. Introduction. Ectopic pregnancy is the fourth most common cause of maternal death in the United Kingdom, accounting for 80% of early pregnancy deaths (Lewis and Drife 2004). Furthermore, it is still the most common cause of maternal death in the 1st trimester of pregnancy (Condous G 2006) affecting 1:100 pregnancies (Ectopic Pregnancy Trust 2007). For this case study I will discuss the essence of scanning women who present in EPU’s with a positive pregnancy test and any symptoms of a possible ectopic pregnancy. CASE REPORT This is the case of 32yrs old primigravida referred to an early pregnancy unit by her GP with a history of irregular menstrual cycle, heavy bleeding for a week and a positive pregnancy test which she did 10days earlier. Conception was spontaneous. Her Gestational age by her LMP was 4weeks and 4days. A transvaginal ultra-sound was performed which identified the absence of an intrauterine gestation sac. The endometrial thickness was 2. 0mm, midline echo intact and thin and homogenous. The right ovary was visible and normal; the left ovary was visible and normal with a corpus luteum. An adnexal mass separate from the ovary was found adjacent to the left ovary (appendix 1). There was free fluid in the pouch of Douglas with was ground glass appearance which was consistent with haemoperitoneum and was tender to the left were the mass was situated (appendix 2). In view of the findings a left tubal ectopic was diagnosed. In keeping with the department protocol an urgent BHCG and progesterone was done whiles she was referred to the emergency team for further management. Result came back as BHCG 72 iu/l and progesterone 3. 00nmol/l.. She had a laparoscopic salpingectomy for a left tubal ectopic pregnancy. Histology of the product removed laparoscopically was positive of an ectopic, and a repeat BHCG was repeated after a week. The patient was started on antibiotics and recovered successfully. DISCUSSION An ectopic pregnancy is an extra uterine pregnancy. The most common site for implantation is the fallopian tube; however, the conceptus may implant in the ovaries, the cervix, or the abdomen (Drife J, Magowan B 2004). An ectopic pregnancy is a potentially life-threatening gynaecological emergency hat requires urgent intervention. With the above case her LMP indicated a pregnancy of less than 5weeks. She would have been considered outside the criteria of finding an ectopic pregnancy, and would have been considered a possible early miscarriage. With the patients history of irregular bleeding a decision was made to scan. An irregular period can mean that ovulation does not match her last menstrual cycle. All sexually active women of reproductive age who present with lower abdominal pain, with or without vaginal bleeding; an ectopic pregnancy must be excluded. When woman present in a clinic and has had a positive test either at home or at a GP practice it is an indication she is pregnant, and as mention by (Bisset, et al 2002) the role of ultrasound is to identify the site of the pregnancy, if an intrauterine pregnancy is not found then ectopic pregnancy should be considered. Likewise a study by (Haider et al 2006) found out that providing ultrasound as an initial assessment with suspected ectopic has improved clinical management. She should be scan to identify the site of the pregnancy; this was why the decision to scan these women in the department even before an HCG test is carried out. but with her history of irregular period a decision should be made to scan. (The Early Pregnancy RCOG guidelines 2006) confirms a BHCG below 100 iu/l and progesterone below 60iu/l should be treated as an ectopic. When the scan was done and an endometrium of 2mm was seen. The endometrium thickness and appearance can be can be deceptive and these findings can be interpreted as a non pregnant uterus The urine dipstick test for beta-hCG (urinary pregnancy test) carried out is a quick, easy, and sensitive test. It has a sensitivity of 99% at a urine beta-hCG level greater than 25 IU/L, If a woman has a negative urinary pregnancy test, this almost invariably means that she does not have an ectopic pregnancy. However a blood beta-HCG of 72 iu/l was a low level in keeping with guidelines and if this was done prior to the scan it would have been interpreted as a possible failing pregnancy. However, (Condous G, 2006) insists that if it is positive the woman should have a USS. As the vast majority of ectopic pregnancies are tubal, there is ongoing debate in regard to the best method to investigate and diagnosing (tubal) ectopic pregnancy. In Condous report it was recommended that a urine test be done but most patients would have had a test prior to their visit in the clinic. An ectopic pregnancy should be suspected in any woman of reproductive age with any symptom the above patient presented with; however these can be associated with symptoms of miscarriages or other non-pregnancy related etiology. Clinicians should be very suspicious of this symptom although patients can present with others. A recently published review by (Sawyer and Jurkovic 2007) found that the most accurate way to diagnosing an ectopic pregnancy is the use of a combination of ultrasonography, serum beta-hCG, and histology, either following laparoscopy or dilatation and curettage (D&C). These were all carried out in the purpose of diagnosing, confirming and ensuring a resolution to the problem. However, unlike ultrasonography, neither biochemistry nor histology is available immediately, and when presented with a pregnant woman with pain and/or vaginal bleeding, clinicians must urgently exclude an ectopic pregnancy. As such, the initial investigation should be ultrasonography. With the above patient the ultrasound identified fluid in the pouch of Douglas and haemoperitoneum which could have been a rupturing corpus luteal cyst could be the closest differential diagnosis; however the thick tubal ring and a solid corpus luteum seen in this case strongly favours ectopic gestation as the diagnosis (appendix 3). This case highlights an example of a situation in which an ectopic pregnancy was adequately diagnosed rather than of a complete miscarriage. Free fluid was noted, it was echogenic suggestive of haemoperitoneum. Colour. Doppler study reveals a highly vascular ‘ring of fire’ appearance surrounding the tubal ring, confirming that the cystic adnexal mass is an ectopic gestational sac. This appearance is due to a high velocity, low resistance, and trophoblastic flow through the feeding branch of the uterine artery on the affected tubal gestation site, which may aid in narrowing the differential, leading to early detection of the condition. It is usually seen as a variable sized mass, consisting of a hypoechoic centre and surrounded by a thick echogenic rim. This tubal ring can be used to distinguish an ectopic from a ruptured corpus luteum cyst, which is its closest differential. Separate studies by (Ash et al 2007) and (Vaisky et al 2007) demonstrated the value of transvaginal colour flow Doppler in aiding the diagnosis of cornual ectopics. REFERENCES Ash, A, Smith, A, Maxwell,. D (2007) Caesarian scar Pregnancy. British Journal of Obstetrics and Gynaecology. Volume 114:3:253-263 Bisset R. , Khan A, Thomas N (2002)-Differential Diagnosis on Obstetric and Gynaecological Ultrasound. Second Edition. Elsevier Science limited. London. Condous G. Ectopic pregnancy – risk factors and diagnosis. Aust FAM Physician. 2006; 35:854–857. Drife J, Magowan B, editors. Clinical Obstetrics and Gynaecology. London, United Kingdom: Saunders; 2004. pp. 169–171. Haider . Z, Condous. G, Khalid. A. , Kirk. , Bourne. T,. Van Calster. B (2006) Impact of the availability of sonography in The Acute Gynaecology Unit Lewis G. , Drife J, Why Mothers Die 2000–2002 – The Sixth Report of Confidential Enquiries into Maternal Deaths in the United Kingdom; London, United Kingdom: Royal College of Obstetricians and Gynaecologists; 2004. Royal College of Obstetrician and Gynaecologist (2006). Green Top Guidelines in Early Pregnancy loss (WWW) http://www. rcog. org. uk/resources/public/pdf/green top 25 management epl. pdf (April 5th 2007). Sawyer E, Jurkovic D. Ultrasonography in the diagnosis and management of abnormal early pregnancy. Clinical Obstet Gynecol. 2007; 50:31–54. Vasky, D. , Hamani Y. , Verstanig, A. , Yagel, S (2007)The use of 3D rendering, VCI-C,3d Power Doppler and B flow in the Evaluation of Interstitial Pregnancy with Arteriovenous malformation treated by selective Uterine Artery Embolization. Ultrasound in Obstetric and Gynaecology . Volume 29:3:352-355.

Thursday, January 2, 2020

Comparisons of the Lifestyles of Paleoindians in North and...

Through ice-free corridors and water logged routes, Paleoindians travelled from Alaska to Siberia to enter the New World. Over their travels, they discovered new tools, hunting methods and traveling/living techniques. Paleoindians in both North and Central America typically lived in bands of up to 50 people. They were makers of fire and creators of diverse stone tool technology. They had the same physical features in both areas, including hair colour and texture, skin tone, blood types and dentition marks. (Rivals Semprebon, 2012, pg. 1608). These similarities are immediately noticeable when analysing an archaeological site, but others such as the original Paleoindian stone toolkit being present in each region, similar hunting methods and travel techniques become evident throughout the scrutiny of North and Central American sites. Transition from the Old World to New World Since the 16th century, the Bering Strait region has been viewed as the likely route of travel from the Old World to the New World. Paleoindians moved into North America beyond the Bering Land Bridge between Eastern Siberia and present-day Alaska during the Late Glacial Maximum (LGM) when sea levels were significantly lowered due to the Quaternary glaciation. (Rivals Semprebon, 2012, pg. 1608-1609). Pleistocene animals grazed their way through ice-free corridors, water logged routes, across Beringia and into Siberia, leaving footprints in the dry land in which hunter gatherer Paleoindians