Cells Essays - Organelles, Chloroplast, Cell, Thylakoid,

Cells Proteins made from ribosomes attached to the rough endoplasmic reticulum enter the lumen of the ER and move to the smooth endoplasmic reticulum. A small vacuole (vesicle) pinches off the smooth ER and carries the protein to the Golgi apparatus, where it is further processed. ------------------------------------------------------------- Mitochondria are bounded by a double membrane. The inner membrane is folded to form little shelves, called cristae, which project into the matrix, an inner space filled with a gel-like fluid. -------------------------------------------------------------- A vacuole is a large membrane-enclosed sac that usually functions as a storage area. Plant vacuoles contain not only water, sugars, and salts but also pigments and toxic substances. The pigments are responsible for many of the red, blue, or purple colors of flowers and some leaves. ------------------------------------------------------------ The green pigment chlorophyll, found within the grana, makes chloroplasts and leaves green. Chlorophyll absorbs solar energy, and chloroplasts convert this energy into ATP molecules. ----------------------------------------------------------- Chloroplasts carry on the process of photosynthesis, in which light energy is used to produce food molecules, such as glucose. Chloroplasts take in carbon dioxide, water, and solar energy in order to produce glucose and oxygen. ------------------------------------------------------------ The energy-related organelles, chloroplasts and mitochondria, convert one form of energy into another. While chloroplasts are unique to plant cells, mitochondria are found in both plant and animal cells. ------------------------------------------------------------- Chloroplasts carry on photosynthesis, during which light energy (photo) is used to produce food molecules, like glucose (synthesis). Chloroplasts take in carbon dioxide, water, and solar energy in order to produce glucose and give off oxygen. ------------------------------------------------------------ Mitochondria are often called the powerhouses of the cell: just as a powerhouse burns fuel to produce electricity, the mitochondria convert the chemical energy of glucose products into the chemical energy of ATP molecules. -------------------------------------------------------------- Chromatin, a threadlike material, contains DNA and is found within the nucleus. At the time of cell division, chromatin condenses into rodlike structures called chromosomes. ---------------------------------------------------------- The middle lamellae, a region between cell walls, contains a sticky substance, usually pectin. Lignin is a substance found in secondary cell walls that makes them even stronger than primary cell walls. ------------------------------------------------------------ Autodigestion is important during development. For example, when a tadpole becomes a frog, the enzymes within lysosomes digest the cells of the tail, and the fingers of a human embryo are at first webbed, but they are freed from one another by lysosomal action. ------------------------------------------------------------- Lysosomes, vesicles formed by the Golgi apparatus, contain hydrolytic enzymes that can digest macromolecules. Macromolecules are sometimes brought into a cell in vesicles formed at the cell membrane. A lysosome can fuse with such a vesicle and digest its contents into simpler molecules, which then enter the cytoplasm. ------------------------------------------------------------- Special vacuoles (membrane-enclosed sacs) called peroxisomes are often attached to smooth ER, and these contain enzymes capable of detoxifying drugs. ------------------------------------------------------- A chloroplast is bounded by a double membrane. Inside the structure, there is even more membrane organized into flattened sacs called thylakoids. The thylakoids are piled up like stacks of coins, and each stack is called a granum. There are membranous connections between the grana called lamellae. The fluid-filled space about the grana is called the stroma. ------------------------------------------------------------- Inside the chloroplast, there is membrane organized into flattened sacs called thylakoids. The thylakoids are piled up like stacks of coins, and each stack is called a granum. The fluid-filled space about the grana is called the stroma. ------------------------------------------------------------- The nucleus is a large organelle that has a nuclear envelope, chromatin and nucleoli. The nuclear envelope is a double membrane that keeps the contents of the nucleus separate from the cell's cytoplasm. Pores in the nuclear envelope allow large molecules to pass into and out of the nucleoplasm, the fluid interior of the nucleus. ------------------------------------------------------------- Ribosomes are the site of protein synthesis in the cytoplasm. They can be attached to the endoplasmic reticulum or lie free within the cytoplasm. When several ribosomes are making the same protein, they are arranged in a functional group called a polysome. ------------------------------------------------------------ Both plant and animal cells have cell membranes, nuclear membranes, mitochondria, and vacuoles. Chloroplasts are found in plant cells but not in animal cells. ---------------------------------------------------------- All plants have a cell wall, located outside the cell membrane. The primary cell wall contains cellulose whereas the secondary cell walls contain lignin. The middle lamella, a region between cell walls, contains a sticky substance, usually pectin. ---------------------------------------------------------- In the process Cells Essays - Organelles, Chloroplast, Cell, Thylakoid, Cells Proteins made from ribosomes attached to the rough endoplasmic reticulum enter the lumen of the ER and move to the smooth endoplasmic reticulum. A small vacuole (vesicle) pinches off the smooth ER and carries the protein to the Golgi apparatus, where it is further processed. ------------------------------------------------------------- Mitochondria are bounded by a double membrane. The inner membrane is folded to form little shelves, called cristae, which project into the matrix, an inner space filled with a gel-like fluid. -------------------------------------------------------------- A vacuole is a large membrane-enclosed sac that usually functions as a storage area. Plant vacuoles contain not only water, sugars, and salts but also pigments and toxic substances. The pigments are responsible for many of the red, blue, or purple colors of flowers and some leaves. ------------------------------------------------------------ The green pigment chlorophyll, found within the grana, makes chloroplasts and leaves green. Chlorophyll absorbs solar energy, and chloroplasts convert this energy into ATP molecules. ----------------------------------------------------------- Chloroplasts carry on the process of photosynthesis, in which light energy is used to produce food molecules, such as glucose. Chloroplasts take in carbon dioxide, water, and solar energy in order to produce glucose and oxygen. ------------------------------------------------------------ The energy-related organelles, chloroplasts and mitochondria, convert one form of energy into another. While chloroplasts are unique to plant cells, mitochondria are found in both plant and animal cells. ------------------------------------------------------------- Chloroplasts carry on photosynthesis, during which light energy (photo) is used to produce food molecules, like glucose (synthesis). Chloroplasts take in carbon dioxide, water, and solar energy in order to produce glucose and give off oxygen. ------------------------------------------------------------ Mitochondria are often called the powerhouses of the cell: just as a powerhouse burns fuel to produce electricity, the mitochondria convert the chemical energy of glucose products into the chemical energy of ATP molecules. -------------------------------------------------------------- Chromatin, a threadlike material, contains DNA and is found within the nucleus. At the time of cell division, chromatin condenses into rodlike structures called chromosomes. ---------------------------------------------------------- The middle lamellae, a region between cell walls, contains a sticky substance, usually pectin. Lignin is a substance found in secondary cell walls that makes them even stronger than primary cell walls. ------------------------------------------------------------ Autodigestion is important during development. For example, when a tadpole becomes a frog, the enzymes within lysosomes digest the cells of the tail, and the fingers of a human embryo are at first webbed, but they are freed from one another by lysosomal action. ------------------------------------------------------------- Lysosomes, vesicles formed by the Golgi apparatus, contain hydrolytic enzymes that can digest macromolecules. Macromolecules are sometimes brought into a cell in vesicles formed at the cell membrane. A lysosome can fuse with such a vesicle and digest its contents into simpler molecules, which then enter the cytoplasm. ------------------------------------------------------------- Special vacuoles (membrane-enclosed sacs) called peroxisomes are often attached to smooth ER, and these contain enzymes capable of detoxifying drugs. ------------------------------------------------------- A chloroplast is bounded by a double membrane. Inside the structure, there is even more membrane organized into flattened sacs called thylakoids. The thylakoids are piled up like stacks of coins, and each stack is called a granum. There are membranous connections between the grana called lamellae. The fluid-filled space about the grana is called the stroma. ------------------------------------------------------------- Inside the chloroplast, there is membrane organized into flattened sacs called thylakoids. The thylakoids are piled up like stacks of coins, and each stack is called a granum. The fluid-filled space about the grana is called the stroma. ------------------------------------------------------------- The nucleus is a large organelle that has a nuclear envelope, chromatin and nucleoli. The nuclear envelope is a double membrane that keeps the contents of the nucleus separate from the cell's cytoplasm. Pores in the nuclear envelope allow large molecules to pass into and out of the nucleoplasm, the fluid interior of the nucleus. ------------------------------------------------------------- Ribosomes are the site of protein synthesis in the cytoplasm. They can be attached to the endoplasmic reticulum or lie free within the cytoplasm. When several ribosomes are making the same protein, they are arranged in a functional group called a polysome. ------------------------------------------------------------ Both plant and animal cells have cell membranes, nuclear membranes, mitochondria, and vacuoles. Chloroplasts are found in plant cells but not in animal cells. ---------------------------------------------------------- All plants have a cell wall, located outside the cell membrane. The primary cell wall contains cellulose whereas the secondary cell walls contain lignin. The middle lamella, a region between cell walls, contains a sticky substance, usually pectin. ---------------------------------------------------------- In the process

Free Essays on Operating Systems

OPERATING SYSTEMS An operating system is the program that manages all the application programs in a computer system. This also includes managing the input and output devices, and assigning system resources. Operating systems evolved as the solution to the problems that were evident in early computer systems, and coincide with the changing computer systems. Three cycles are clear in the evolution of computers, the mainframe computers, minicomputers and microcomputers, and each of these stages influenced the development of operating systems. Now, advances in software and hardware technologies have resulted in an increased demand for more sophisticated and powerful operating systems, with each new generation able to handle and perform more complex tasks. The folowing report examines the development of operating systems, and how the changing tehcnology shaped the evolution of operating systems. First Generation Computers (19451955) In the mid1940's enormous machines capable of performing numerical calculations were created. The machine consisted of vacuum tubes and plugboards, and programming was done purely in machine code. Programming languages were unheard of during the early part of the period, and each machine was specifically assembled to carry out a particular calculation. These early computers had no need for an operating system and were operated directly from the operator's console by a computer programmer, who had immediate knowledge of the computers design. By the early 1950's punched cards were introduced, allowing programs to be written and read directly from the card, instead of using plugboards. Second Generation Computers (19551965) In the mid1950's, the transistor was introduced, creating a more reliable computer. Computers were used primarily for scientific and engineering calculations and were programmed mainly in FORTRAN and assembly language. As computers became more rel... Free Essays on Operating Systems Free Essays on Operating Systems OPERATING SYSTEMS An operating system is the program that manages all the application programs in a computer system. This also includes managing the input and output devices, and assigning system resources. Operating systems evolved as the solution to the problems that were evident in early computer systems, and coincide with the changing computer systems. Three cycles are clear in the evolution of computers, the mainframe computers, minicomputers and microcomputers, and each of these stages influenced the development of operating systems. Now, advances in software and hardware technologies have resulted in an increased demand for more sophisticated and powerful operating systems, with each new generation able to handle and perform more complex tasks. The folowing report examines the development of operating systems, and how the changing tehcnology shaped the evolution of operating systems. First Generation Computers (19451955) In the mid1940's enormous machines capable of performing numerical calculations were created. The machine consisted of vacuum tubes and plugboards, and programming was done purely in machine code. Programming languages were unheard of during the early part of the period, and each machine was specifically assembled to carry out a particular calculation. These early computers had no need for an operating system and were operated directly from the operator's console by a computer programmer, who had immediate knowledge of the computers design. By the early 1950's punched cards were introduced, allowing programs to be written and read directly from the card, instead of using plugboards. Second Generation Computers (19551965) In the mid1950's, the transistor was introduced, creating a more reliable computer. Computers were used primarily for scientific and engineering calculations and were programmed mainly in FORTRAN and assembly language. As computers became more rel...

Discuss the arguments for and against the use of toluidine blue Essay

Discuss the arguments for and against the use of toluidine blue staining as a screening method for oral cancer in dental practic - Essay Example This paper elucidates on the arguments for and against the use of toluidine in screening for oral cancer. The use of toluidine blue in uterine and oral cancer screening was pioneered by Richart in 1962. A 1% aqueous solution of toluidine blue is painted over the target area for ten seconds followed by a rinse of 1% solution of acetic acid. The toluidine blue binds to the DNA on surface cells, causing the surface to take on a bluish hue. The amount of DNA material present may be used as an indication of suspected dysplasia or neoplasia (Richart 1962). 2.0. Arguments for toluidine screening Jones and Rankin (2008) consider toluidine blue staining as a diagnostic aid for the dental professional in the evaluation of the possible malignancy of oral lesions. The potency of staining with toluidine blue has been likened to that of brush biopsy in terms of early detection, speeding up of biopsy and subsequent diagnosis of oral cancer. Application of aqueous toluidine blue to a lesion followed by a rinsing of 1% acetic acid results in selective binding with dysplastic and malignant cells accurately. The blue stain also marks a good site to extract for biopsy. Extreme care should, however, be practiced to ensure that the dye is neither mutagenic nor carcinogenic for best results. Patton, Epstein and Kerr (2008) performed a systematic review of literature related to several adjunctive techniques used in the early detection of oral premalignant and malignant lesions or OPML, such as toluidine blue. A total of 23 articles were reviewed wherein the majority focused on the use of toluidine blue. Results of the review revealed the effectiveness of toluidine blue in diagnosing oral premalignant and malignant lesions in high-risk populations and suspected mucosal lesions. However, clinicians are advised not rely much on diagnostic adjuncts alone. A complete oral mucosal examination is recommended together with specialty referrals or tissue biopsy to correctly diagnose OPML. Epste in, Silverman, Epstein, Lonky and Bride (2008) evaluated the effects of ViziLite, a chemiluminiscent light source in conjunction with toluidine blue in the process of verifying lesions identified by oral soft tissue examinations. Lesion assessment by chemiluminiscense combined with toluidine blue staining was compared with conventional visual examination. Subsequently, the suspected lesions were subjected to biopsy and diagnosed through conventional histopathological methods. Moreover, toluidine staining was performed on lesions related to severe dysplasia, carcinoma in situ, and squamous cell carcinoma. Results of the assessment show an improvement in the brightness and sharpness of margin in 60 out of 97 identified lesions that underwent the chemiluminiscent exam. Meanwhile, toluidine staining exhibited a false positive rate of 55.26% while maintaining a 100% negative predictive value (Epstein, Silverman, Epstein, Lonky and Bride 2008). Fedele (2009) described toluidine blue as an indispensable tool in identifying the area damaged by a malignant lesion due to its ability to stain nucleic acids. This effect makes it easier to remove malignant lesions since toluidin blue clearly marks the boundaries of the lesion, thus allowing precise excision. Recent studies on the use of toluidine blue were rather limited due to the dearth of research efforts in relation to randomized controlled trials, histological diagnosis

History of Mathematics Essay Example | Topics and Well Written Essays - 500 words

History of Mathematics - Essay Example For instance, with the use of sequence, one may be able to solve how many pairs of rabbits will be produced annually assuming that each pair reproduces a new pair monthly with the new pair becoming productive starting from the second month (Boyer & Merzbach 256). Furthermore, the sequence may be applied to phyllotaxy or growth patterns of plant leaves as they spiral up the stem or trunk. With the sequence, the plant may not have to be stripped to determine the age or rings of the trunk ("Wikipedia"). The Dark Ages refers to the period in the Middle Ages to the first few centuries after the fall of Rome when knowledge including those pertaining to mathematics is said to deteriorate. This is evidenced by the textbooks used by Church schools in the Middle Ages were based on the primitive works of Cassiodorus and Isidore of Seville and featured limited coverage of arithmetic of Boethius. The only use of mathematics identified was for ecclesiastical calendars and growth in mathematical knowledge is limited to the representation of number by means of the fingers. (Boyer & Merzbach 249) This period is dubbed as the Dark Ages to reflect the loss of enlightenment provided by classical learning and prevalence of ignorance and barbarism (Hirsch, Kett & Trefil).

Different Aspects of E-Business Essay Example | Topics and Well Written Essays - 500 words

Different Aspects of E-Business - Essay Example An 'e-shop' is merely a shop that uses electronic means of marketing. (Timmers, 2000) In this business potential customers would often ask the agent if they have a website and they sound disappointed when the agent replies in negative. There are some amazing websites developed by some real estate businesses and just looking at the site can convinces a customer of the power of the Internet. A successful e-business organization is the one that understands the requirement and meets the expectations of their customers. (Greengard, 2000) Not only do they have pictures of properties on sale, they also offer immediate quote service, online chat service with a staff member and also make suitable recommendations based on a person's needs. Real estate sector is not comprised of many big players. In most cases, this sector is run by small business owners- who have interest in the field and the resources to conduct marketing and sale of properties. It is precisely due to this that Internet offers greater benefits to the real estate business owners. It provides them with the much-needed exposure and opens marketing avenues for them so they can reach a sizeable population of home seekers. Potential customers find it easier to visit websites and check out various real estate services in the area and call the ones with the kind of properties they are seeking.

The two approaches of accounting research

The two approaches of accounting research The positivist approach and the critical approach are the two approaches of accounting research. This article explains the concepts of positivist approach and critical approach, and then explains some of the problems of these two approaches. This article discusses the inter-relationship between accounting research, accounting standards and accounting practice. Through the research findings, this article use the case of intangible assets to illustrates how accounting research impact on accounting standards. Secondly, this article shows how accounting standards effects accounting practice. Thirdly, this article explains the inter-relationship between accounting research and accounting practice. Introduction The positivist approach and the critical approach are the two methodologies of accounting research. Hooper, Davey, Liyanarachchi and Prescott (2008, p20) described that the positivist approach is generally considered to be a combination of induction and deduction. The traditional view for the positive approach to research is to understanding and solving problems. The traditional characteristics of the positive approach are empiricism, logic and causality. These characteristics are often referred to as ontological, epistemological and methodological characteristics of a research paradigm. Positive accounting research experiments to describe what is without making any value judgments as to how things should be. The positive approach has been important in recent years. The critical approach to accounting research does not provide a particular method or methodology for research but rather a dialectic and Socratic approach to the evaluation of knowledge claims (Hooper et al, 2008, p33). T he critical research focus on the accounting theory that is concerned with resolving conflicts between the corporation and general public. The only ideology is the belief in humanness and the concomitant and emancipation of humankind. Critical theory offers processes for the consideration and evaluation of knowledge claims without providing a single way forward for the researcher. These two accounting research approaches are not mutually exclusive but are complementary. Hooper et al (2008) states that the positive approach has a number of problems, such as lack of agreement on what the positive approach actually is; appeals to the authority of science but focuses on behavior and so on. The critical approach also has some problems, such as the critical research cannot generalize findings; critical research cannot predict or replicate studies. Both of these two theories have its own advantages and disadvantages, it is necessary to combine the two methodologies in actual accounting practice environment. Accounting research helps accounting standards setters and others understand the economic world, but accounting research does not seek prescriptions of techniques to make the world better. However, knowing what works and what does not work can help corporations or standard setters choose techniques that have the best chance of working in as yet untested situations. Accounting standards have been categorized on the basis of their nature into two categories: principal-based standards and rule-based standards. Hooper et al (2008) states that accounting standards are based on a set of principals and concepts. Intangible assets defined as non-physical and non-monetary sources of probable future economic profits accruing to the firm as a result of past events or transaction (Canibano et al, 2000). Intangible assets should be accounted and reported in the financial statement. Maines,  Bartov, Fairfield, and Hirst (2003) states that for pragmatic reasons, most research on intangible assets focuses on those intangibles, intangible assets generated by RD expenditures. RD expenditures data are widely available because RD expenditures must be disclosed separately under FASB No. 2, Accounting for Research and Development Costs. Because there is no such requirement for other types of intangibles assets. Canibano et al (2000) describes that control of the probable future benefits arising from the intangible investment is considered by most accounting standards setting bodies as a basic requisite for recognition. Lev and Zarowin (1999) suggest that intangible assets should be accounted for following the same methods applied for tangible assets, but at the same time some argument arise that there are significant differences between tangible and intangible assets which make it necessary to apply different criteria for the recognition and valuation of the latter (Hendriksen, 1982). According to the SFAC6, paragraph 25, the FASB (1985a) considers the ownership or control of the future benefits as the main requisite for the recognition of intangibles. If it is focus on the ownership of the benefits, then intangible assets such as human resource could be recognized. There is a new trend in accounting research, which seems to be providing strong support to reporting intangibles (Canibano et al, 2000). Accounting research suggests to use disclosures on intangibles assets and those intangibles expenditures have future much benefits, but that these future benefits are more like uncertain than those associated with conventionally recognized assets. Thus, there is some empirical support for the capitalization of estimated RD intangibles. Given research results, Maines et al (2003) makes the following recommendations: first, support the FASBs decision to add another project which considers the disclosure and recognition of information related to intangibles assets. Second, believe that the FASB needs to consider recognition of internally generated intangibles asset s, because current accounting standards require capitalization economic similar as intangibles assets acquired externally. Third, Despite our support for intangible assetss disclosures related to and possible recognition , we encourage the FASB to proceed carefully on disclosures and recognition information on intangibles, given significant uncertainties related to accounting research in this paticular area. Concerns related to this research include the following. Finally, while research documents associations between intangibles information and designs make causal inference difficult. All of the accounting research in this area is based on RD expenditures for data availability reasons. It is not clear how easily these accounting research results generalize to other types of intangibles assets. Accounting Standards play an important role in accounting practice. McCombie and Deo (2005) state that accounting standards provide the accountant with a guideline to reports economic transactions and events for an organization. The accounting standards are also described as a piece of delegated legislationparliament has given the power of making accounting standards to a body that has experts on it rather than developing the documents itself as a body of legislators (Ravlic, 2003). The number of companies that have to apply standards in preparing financial reports is therefore quite important. Macve (2010) states that audited accounts are part of an organization that defines the economic environment in a country, or across countries, and enables investors to have confidence in the system as a whole as one to which to entrust their money. This was justified by Edwards (1938) in his call for a revolutionary reform of UK accounting practice. It still seems as true today. In the view of the US SEC it is the overall regime of standards of corporate governance, accounting, auditing and enforcement in a country that lowers the cost of capital to firms in that economy and thereby stimulates investment and economic growth. This effect is probably greater than what any individual firm can achieve by improving its own accounting and disclosures (cf. Botosan, 2006). The accelerating growth of accounting practices over the years has changed the format of corporate annual reports. International Accounting Standards (IASs) and International Financial Reporting Standards (IFRS), along with other statutory requirements, have changed the way in which financial statements are reported (Gouws and Cronjà ©, 2008). All the information is generated by a diversity of accounting practices, all of which are therefore worth researching. Accounting research leads to an enhanced understanding of the fact that these practices are driven by two systems that provide the information included in corporate annual reports. This shows that practices peripheral to traditional accounting practices also have an important role to play, both for educational institutions and accounting. Accounting practices should not be seen in isolation (that is, only from an accounting perspective), as they are multidisciplinary in nature. Environmental practices and information, social practices and information, ethical practices and information, as well as management accounting practices and information, together with financial accounting practices and information, form the context within which reporting in corporate annual reports takes place ( Gouws and Cronjà ©, 2008). Accounting Research have made Accounting Practice more efficient and effective, but Accounting research and accounting practice are not always seemed to be synchrony. One of the great attractions of conducting applied accounting research in accounting practice is that the research topics extend beyond the normal boundaries. It brings worldviews into conflict, improves accounting practice, and raises doubts about professional social and values (Schiehll, Borba, Murcia, 2007). HENDRIKSEN (1982) corroborates this argument, adding that accounting theory may be defined as logical reasoning in the form of two principles that: (1) accounting research provide a general frame of reference by which accounting practice can be evaluated, and (2) accounting research guide the development of new accounting practices and procedures. However, some of the research shows results of accounting research have not led to changes in accounting practice; this may be caused by practitioners not accepting the research findings or a lag in putting new accounting theory into accounting practi ce. This has been an over-emphasis on a theory and the research results in some cases, and it is correct that standard-setters and practitioners have not accepted or have been cautious in using the accounting research results as a basis for new accounting rules and practices, such as market efficiency research. However, in other cases research appears to be quite useful to standard setters as they establish new rules and practices, such as earnings management research. Llewellyn and Sue (1996) states that theories for practice would place more emphasis on theory as a map or recipe or instructions manual which provide means by which we can do things in the world or cope with events. Auditing Practice, Research, and Education, A Productive Collaboration, published in 1995 through a joint effort of the American Accounting Association and the AICPA, set the goal of preparing a monograph documenting the successes of prior, less-harried times when collaborative efforts produced significan t insights and often solutions to challenging auditing problems (Bell and Wright, pg 178). They explain the rich heritage of practitioner or academician collaboration in addressing auditing challenges. The authors indicate the importance of a periodic review of academic research for use of those in practice. The monograph also calls for increased interaction with practitioners, the use of academic research fellows in practice, and integration of the research process into audit education (Anderson et al, 2003). Accounting practice depends on accounting research, and accounting research guide the development for accounting practice. Conclusion Both of the positivist approach and the critical approach has its own advantages and disadvantages, the best way to use accounting research is to combine the two methodologies in actual accounting practice environment. The inter-relationships between accounting research, accounting standards and accounting practice are Accounting research helps accounting standards setters and others understand the economic world, accounting research have made accounting Practice more efficient and effective, but accounting research and accounting practice are not always seem to be synchrony. Accounting standards provide the accountant with a guideline to reports economic transactions and events for an organization.

The Trebuchet Essay examples -- medieval siege machine

Used by castle commanders during times of peace to hurl roses to ladies during tournaments, trebuchets proved a deadly weapon in the field of ancient warfare. Flinging a wide variety of objects hundreds of yards, the trebuchet became the weapon of choice for laying siege to a castle. Its incredible range could often place it beyond the effectual defense range of the castle archers, thereby permitting the besiegers to destroy the defender's walls with little interference. During extended sieges, trebuchets were often used to hurl large quantities of dung, dead animals, and other such items to encourage disease throughout the besieged city. Trebuchets earned a reputation for being much more accurate and precise than their onager and catapult counterparts. Not only was this accuracy a benefit, but being based on rotational motion and leverage rather than torsion (spring power) and lacking in a throwing arm stop, the trebuchet proved a much safer alternative for the personnel operating it. Onagers and Mangonels would literally explode on occasion when the torsion proved too great or a crack developed in the throwing arm due to the rapid stops it experienced. All in all, the Trebuchet was a fearsome weapon of mass destruction during the Middle Ages, a force to be reckoned with. Trebuchets only lost favor when cannons emerged, and the primary benefit of the cannon that the trebuchet lacked was not in fact power, but rather mobility. Smaller, more maneuverable cannons rapidly overran the position of the trebuchet in most armies across the world. Warwolf, the legendary trebuchet built by the English Army to destroy Castle Urquhart, which was located in the Highlands of Scotland, on the shores of the also infamous Loch Ness. Par... ...elease and a more horizontal trajectory, with higher velocity. In an attempt to better understand the components of the trebuchet and to permit the viewer a better idea of the manner in which the firing of a trebuchet occurs, a trebuchet constructed entirely of K-nex was built this past week. The counterweight consisted of 5000 steel bb's wrapped in plastic and duct tape, while the sling itself was made of duct tape and twine. The remaineder of the trebuchet, including the throwing arm, were constructed purely from K-nex. Standing some 3 feet tall, this trebuchet could repeatedly launch a 2-3oz object in excess of 20 feet. Lengthening the sling proved valuable, increasing velocity and range considerably. However, a point was reached at which the sling length could be said to be optimized, and lengthening it further only created unpredictable release angles.