Critique of Systematic Review - 1360 Words

Critique of Systematic Review Mary Odenwalder Nur 518 April 7, 2014 Jane Cash Critique of Systematic Review The World Health Organization (WHO) recommends that all infants breastfeed exclusively until six months old to achieve optimum growth. Despite this recommendation, only one out of every three children are exclusively breastfed for the first six months. This includes countries that have a high rate of breastfeeding initiation. Recent data has shown that the exclusive breastfeeding rates over the last 15 years have only risen about six per cent, from 33% to 39%. Breask milk protects children against childhood illnesses such as gastroenteritis, respiratory tract infections, otitis media, atopic dermatitis, asthma, and SIDS.†¦show more content†¦This previous review only discussed exclusive breastfeeding. In this review the authors also included the results of the interventions resulting in predominant, partial, and no breastfeeding. The included studies were evaluated for quality according to the Child Health Epidemiology Reference Group (CH ERG) adaptation of Grading of Recommendation, Assessments, Development and Education (GRADE) criteria. The following databases were searched for published literature, PubMed, Medline, Cochrane Library, EMBASE and WHO. These databases were searched for files that discuss the effects of interventions to promote breastfeeding rates: exclusive, predominant, partial, or no breastfeeding. No language or date restrictions were imposed. These search criteria and database searches gave a variety of article while concentrating on the research question. Two authors independently evaluated each article for relevant using a predefined set of criteria. Inclusion and exclusion criteria were specified and were appropriate for the review. The researchers were concerned with the effect education and support for the mothers had on the exclusive breastfeeding rates of healthy newborns. Inclusion criteria included randomized controlled trials (RCT) or quasi-experimental trails. The types of articles included are those that discussed interventions through education or support given to the mother prenatal/postnatal, or a combination. All delivery types were included. ForShow MoreRelatedSystematic review critique Essay910 Words   |  4 Pagesï » ¿ Critique of Systematic Review of intravenous acetaminophen Chamberlain College of Nursing NR505: Advance Research Methods: Evidence-Based Practice Fall Session A, 2013 Abstract According to the systematic review covered by Apfel, Turan, Souza, Pergolizzi Hornuss, 2013 there is a significant reduction in postoperative nausea and vomiting and opioid use when using intravenous acetaminophen. The reviewers used Medline and Cochrane databases to conduct their search along withRead MoreEssay about NR505 Critique of Systematic Research Review1493 Words   |  6 Pagesï » ¿ Analysis and Application of a Clinical Practice Guideline: Child Passenger Safety Chamberlain College of Nursing NR505 Advanced Research Methods May 2012 Analysis and Application of a Clinical Practice Guideline: Child Passenger Safety Motor vehicle crashes are identified as the leading cause of death in children under 19 years of age across the United States (Sauber-Schatz, West, Bergen, 2014). Due to the large number of child deaths that occur each year,Read MoreA Critique of the Article Progressive Resistance Exercise in Physical Therapy: A Summary of Systematic Reviews803 Words   |  3 PagesCritical Review Objective The objective of this work is to write a critique of the article entitled Progressive Resistance Exercise in Physical Therapy: A Summary of Systematic Reviews and to answer questions relating to the methods, measures and assessments as well as to examine what is missing in the research and whether claims are understated and the limitations to the research. Introduction Progressive resistance exercise (PRE) is reported as a method of increasing the ability of musclesRead MoreEvaluation Of A Research On Management Education1516 Words   |  7 PagesNot† (JME-16-0084-ETR). I have completed the evaluation of your paper by soliciting reviews from three experts, who assessed the potential contribution to management education research. Based on their assessment and mine, I would like to offer a high risk revise and resubmit for this manuscript. As I understand it from my reading and the reviewers’ comments, the aim of this manuscript is to provide a systematic review of criticality in the management education domain. Like most instructors who aspireRead MorePaper1728 Words   |  7 Pagesthese women, medicine has evolved and the option for significant pain relief is available. The question raised when providing this option is, are there negative effects of receiving an epidural too early or late in the process. This critique of this systematic research review (SRR) addresses the, concern that an epidural started too early or late effect labor adversely. Relevance of Research Epidural analgesia is a popular and effective form of pain relief during labor. When placing an epiduralRead MoreA Research Study On Ivf890 Words   |  4 PagesBefore this systematic review published, only two reviews were available of outcomes for singletons after IVF techniques. In comparison with natural conception, it has been proposed that the obstetric results of pregnancies are poorer with IVF/ICSI. Today, it is reported that the number of women that undergo IVF/ICSI process is increasing around the world. With this, I am curious about the risks for women having IVF/ICSI and how perilous it is to them since the process is not natural. I would alsoRead MoreQuality of Life, Research Critique Essay845 Words   |  4 PagesRunning head: QUALITY OF LIFE, RESEARCH CRITIQUE Quality of Life, Research Critique Lisa Spann Grand Canyon University Introduction to Nursing Research NRS-433V Professor Anna Auler October 04, 2012 Quality of Life, Research Critique As the ability to prolong chronological life advances, the question is when is the effort enough or too much? The term coined â€Å"quality of life† or QoL is thrown out to be a point of reference. The certain point at which determined the efforts are no longerRead MoreThe Doctrine Of Angelology1169 Words   |  5 PagesIntroduction The study of the doctrine of Angelology, is a term used in Christian systematic theology. â€Å"The Hebrew word malak simply means â€Å"messenger†; it may refer to a human messenger (1 Kings 19:2) or a divine messenger (Gen. 28:12). The basic meaning of the word is ‘one who is sent.’† Wayne Grudem defines angels as, â€Å"Angels are created, spiritual beings with moral judgement and high intelligence, but without physical bodies.† Holy angels are messengers from God, while Satan â€Å"the god of thisRead MoreEvaluation Of A Research Review1605 Words   |  7 Pages Systematic Research Review Stephanie Rogers Chamberlain College of Nursing NR 505: Advanced Research Methods September 2016 â€Æ' Systematic Research Review As advancements are made in science and technology that relates to the care of patients, it is critical for nurses to be aware of the treatments that have been proven to be evidence-based. Systematic research reviews (SRR) are considered to have the highest ranking or level of evidence falling under level 1 evidence for reliability, validityRead MorePeripheral Intravenous Infusion For Medications, Fluids, And Nutrient Administration926 Words   |  4 Pagesresearch to truly determine its effectiveness. The following systematic research review (SRR) focuses on ten eligible studies regarding the use of heparin as either an intermittent flush or continuous infusion compared to normal saline flushes to prevent thrombosis or occlusion in PIVs from occurring in neonates. Furthermore, this paper will analyze and critique the articles used for this review to determine its overall validity. Critique of Research Rigor Scientific rigor in quantitative research

Bless Me Ultima Character Analysis - 708 Words

In Bless Me, Ultima! Written by Rudolfo A. Anaya, the main character Antonio is greatly affected by the deaths of three characters in this novel, Lupito, Narciso, and Florence. Their deaths cause Tony to question sin, death, forgiveness, the nature of God, and spiritual identity. Lupito, a war veteran that suffers from Post-traumatic stress disorder, death triggers the questioning of moral sin and afterlife, will he be forgiven because of his sickness from war? Narciso, one of Antonios closer friends, influenced Antonio, and his death has an effect of good and evil, and has him to question the nature of God. Florence, also one of Antonios friends, Florence didn’t believe in God because of his past, both of Florence parents†¦show more content†¦Antonio witnessed Tenerio shooting Narciso under the juniper tree. Still I was positive it had been a shot and I bolted forward. It was beneath the big juniper tree that I caught sight of the two figures† (168). As Narciso lay in the snow dying, he whispered to Antonio he needs confession before he passes away.† Muchacho,† his hoarse voice whispered, â€Å"I need confession----I am dying— â€Å"(170). On Easter Sunday after Antonio had been saved he begin to question God about Narciso’s death. â€Å"Why did you allow Narciso to be murdered when he was doing well† (221). Florence, one of Antonio’s friends, does not believe in Catholicism. He questions god because of his past. Florence’s parents are dead, and his sisters are prostitutes. Antonio and Cico takes Florence to see the golden carp, while they went to show Florence the golden carp, they both recognized Horse and the others shouting and waving at them. â€Å"Florence hasn’t come up! He hasn’t come up!† Abel sobbed and tugged at my arm† (239). The kids were telling Antonio and Cico Florence had drowned, â€Å"He drowned, he drowned, â€Å"Bones whimpered† (239). Antonio felt as if he lost another friend, doomed to his dream-wanderings. â€Å"The church had not given him communion with God and, so he was doomed to his dream wanderings, like Narciso and Lupito. Antonio felt as if there was absolutely nothing the church or himself could do for him now. â€Å"I felt that there was nothing the church or I could give him now†Show MoreRelatedCharacter Analysis : Bless Me, Ultima1361 Words   |  6 Pagesourselves. They can expand our thoughts to a multitude of different subjects and force us to be a slave to our dreams, such as facing parental pressure, religious ambivalence and the loss of ones innocence. This is true of Antonio Marez in the novel Bless Me, Ultima by Rudolfo Anaya. Antonio has lost control and begins to succumb to his dreams and loses control of himself. He battles his expectations given to him by his parents and also at the same time has another battle within himself. He is confusedRead MoreBless Me Ultima Character A nalysis702 Words   |  3 Pagesunderstand the world through our own perspective. When people do not quite understand, or do not want to, they often misunderstand situations and other people. Humans tend to label each other as one thing when they can be something else completely. In Bless Me, Ultima, by Rudolfo Anaya, Narciso is misunderstood as just a town drunk when he really is a hero. Lupito has just killed the town sheriff, and all the men are out for his blood. They are searching the bridge and the bushes looking for him when NarcisoRead MoreBless Me Ultima Character Analysis1039 Words   |  5 PagesIn the novel Bless Me, Ultima author, Rudolfo Anaya introduces a character by the name of Antonio Mà ¡rez or â€Å"Tony† as referred to by his friends and family. In the novel Antonio appears to be the embodiment of an entire generation of children that are born to traditional Mexican/Native families but raised in an ever so diverse United States. In a Q A with Rudolfo Anaya at the end of the novel he states, â€Å"my mother was a very religious person, much like Antonio’s mother in the novel. I grew up completelyRead MoreBless Me Ultima Chicano Literature1592 Words   |  7 PagesIntroductory Paragraph Bless Me, Ultima is a Chicano novel written by Rudolfo Anaya in 1972, which includes a magical realism plot. Chicano literature is especially significant in this novel because it helps create a cultural identity for the main character and his community. The novel talks about a petite boy named Antonio; throughout the book Antonio makes his best efforts to try and find the path to which he belongs, he wants to find answers about who he is and wants to learn a lot more aboutRead MoreThematic Analysis Of Bless Me, Ultima1580 Words   |  7 Pages Thematic Analysis of Conflicts in, Bless me, Ultima Differences in others aid to the stimulation of ideas and opinions that expresses an individual s personality. In Rudolfo Anaya’s bildungsroman, Bless Me, Ultima, the struggle between two families and their extreme differences cause numerous conflicts that are constantly present throughout his novel. In this chicano inspired novel, Antonio Marà ©z, the six year old protagonist, is perpetually faced with instances of dissimilarity throughoutRead More Bless Me, Ultima: The Cultural Distress Of A Young Society Essay example3164 Words   |  13 Pages Bless Me, Ultima: The Cultural Distress of a Young Society An answer to the discussion question of whether or not there is a defined border culture would need a great number of years in field research, but we can also observe a few of the characteristics of such border culture just by looking at scholastic essays and books related to the topic. Within the research that I did, I found a number of scholars who, while defining the border, mention all the specific or special characteristics of thisRead MoreKill A Mockingbird By Harper Lee1982 Words   |  8 Pageswelcome and love rather than hypocrisy, racism, and judgement. Task #2: Bless Me, Ultima Whether religious or not, death is a subject that haunts almost everyone with the desire for answers. Antonio Marez in the novel Bless Me, Ultima by Rudolfo Anaya proved this as he was forced to witness and experience the deaths of five people he knew very well. Being born with an excellent sense of spirituality brought him and Ultima, a curandera with extreme healing powers, close together. With Ultima’s guidanceRead MoreAtticus, Scout, And Jem Finch2314 Words   |  10 Pagesraised by Atticus, who passes down his values of equality and righteousness to Scout and her brother Jem. Because she is still growing up, the reader sees and follows as scout learns man lessons about dealing with prejudice by observing the other characters in the story. Scout learns that yielding to prejudice often hurt and cause strife to others and by resisting prejudice we often help others. Hatred and prejudice poison the people they infest. Through her journey and bildungsroman, Scout learnsRead MoreAnalysis Of The Movie Holden Talks With Mr. Spencer Essay1569 Words   |  7 PagesAnalysis: This quote is from the part when Holden talks with Mr. Spencer. Since Holden failing all his classes except one, Mr. Spencer is advising Holden about the importance and the impact of his actions in his life. Holden’s perception of adults is depicted when he curses Mr. Spencer in his mind. By nodding silently to Mr. Spencer’s words, Holden actually disrespects adults. We can easily perceive that Holden feels alienated when Mr. Spencer tells him that he is one of those people on â€Å"the otherRead MoreReview Of Yann Martel s Life Of Pi Essay1337 Words   |  6 Pageshurtful. Pi is found, fed, bathed, and taken to a hospital. There, two Japanese men come to question Pi about what caused the Tsimtsum to sink. He tells his story, which they do not believe, so he offers them a more plausible version, with the animal characters replaced by other humans, which casts doubt on t he original story. Throughout the novel, the story is interrupted by the author’s notes on Pi as he is now, telling this story to the author. After recovering in Mexico he went to Canada, where he

The IPhone at IVK-Free-Samples for Students-Myassignementhelp.com

Questions: 1.Briefly summarize the issues faced by Jim Barton, the CIO at IVK Corporation. 2.How should Barton respond to the Sales Department's request? 3.From a strategic point of view, present two arguments that support the decision to go for the iPhone, and another two arguments against the iPhone. 4.Apparently, Barton is faced with two options: either to accept Sales request or to reject it. Are these the only options? Can you suggest something else? Explain. 5.Discuss the effect of the Mobile Phones on Workplace Environment. In other words, how would the introduction of the iPhones change aspects in the Workplace Environment? 6.Discuss at least three Managerial Issues concerned with the introduction of the IPhones to the sales team. 7.Who should decide which technologies a Company adopts? Use the case to Illustrate your answer. Answers: 1.The CIO of the IVK financial services James Burton has been facing many problems mainly in the IT management department at the company. His issues mainly involves the rise in Non-Standard Service Request (NSR), addition to this the sales representatives have also been found utilizing devices without the consent of the security department in the organization. Moreover, the sales manager has also put a request where the organization IVK has to invest in iphones in the place of notebooks, which the organization was planning to purchase for their employees (Nolan and Austin 2010). However, the CEO of the organization is also interested in using the iphone as he has a positive image of it. Moreover, the security in charge has also mentioned about certain concerns about the utility of the iphone by the organization. Thus, Barton has to take a decision to replace the use of notebook with iphones for their salespersons. 2.Barton must bring into the focus of everyone about the technical issues of the request that has arrived through the sales department. Along with this, there must be an understanding of the objectives of the business so that the best possible option gets to be chosen for the organization. Moreover, he can also do a SWOT analysis by which the advantages and disadvantages of imparting IT support to the iphones and accordingly, allow the utility of a vital number of various devices in the organization. He can further meet the head of sales department to make him clear about is points (Johnston and Marshall 2016). 3.The arguments that support decision of iphones in the organization from a strategic viewpoint can be that this will definitely increase employee satisfaction by using the device of their choice and it will be portable as they will be able to utilize the same device all over with their necessary information in their pockets. On the other hand, disadvantages can be that it will definitely need many resources, which in turn will increase the cost along with it also has issues of security as using non-tested devises can be an advantage for the hackers and therefore there will be a urgent need for modifications in the security policies (Hayes and Kotwica 2013). 4.Apart from whether to accept or to reject sales request Barton must look at the pros and cons that using iphone will have on the organization. However, based on that he has to take the best decision in favor of the company for which he can organize a meeting with the CEO and head of the sales and can reach to a conclusion where the problem will also resolve keeping my mind employees job efficiency, the devices portability and easy accessibility (Nolan and Austin 2010). 5.In the sales department, it has been found that the scenario without iphones it where there is a somewhat control over the download history of all the users. Previously the notebook PC has had the facility of open space technology, which provided customized applications to the security codes. However, if iphone is allowed then this will not be the case but there will be encryption of the data along with supporting the virtual private note works (VPN) (Misra et al. 2016). Moreover, it will be easy to use and will reduce the cost of using a notebook as it is a portable device with updated usages. 6.The three management issues can be concerning the introduction of iphone to the sales team would be that it would be time consuming, as the employees will need some time to learn how to operate this new device. Then, there will be no restrictions upon the sales team for downloading apps from the Appstore and this can be harmful as some apps might have troublesome codes. Lastly, sales team will have to give their access on other parts of their phone so that they can work appropriately, which further come up with security issues. Sandboxing would also not guide much if users decline the access to the phones data repeatedly (Wei and Leimeister 2014). 7.The decision on adopting technologies in an organization can be taken by the IT department, the administration or the CEO of the company. This decision will be based on cost reduction, improvement or efficiency on productivity, quicker time to market, product improvement and competitive surrounding. However, for IVK the decision is solely upon the CIO of this organization Jim Barton to either accept or reject the proposal that has been raised by their sales department about replacing notebooks with iphones (Nolan and Austin 2010). References Hayes, B. and Kotwica, K., 2013.Bring your own device (BYOD) to work: Trend report. Newnes. Johnston, M.W. and Marshall, G.W., 2016.Sales force management: Leadership, innovation, technology. Routledge. Misra, S., Cheng, L., Genevie, J. and Yuan, M., 2016. The iPhone effect: the quality of in-person social interactions in the presence of mobile devices.Environment and Behavior,48(2), pp.275-298. Nolan, R.L. and Austin, R.D., 2010. The iPhone at IVK. Wei, F. and Leimeister, J.M., 2014. Why cant I use my iPhone at work?: managing consumerization of IT at a multi-national organization.Journal of Information Technology Teaching Cases,4(1), pp.11-19.

Leadership Talent Reviews free essay sample

An organization is like a living organism. As the organization develops and matures its need for human capital changes. It will require more people due to growth, a wider range of professional diversity, and replacements as employees leave the organization. Leadership Talent Reviews are a way for an organization to prevent the well of leadership talent from running dry. This study will examine the Leadership Talent Review process at a Department of Defense Agency, as it compares to current trends. The Role of the Human Resource Department It is important to define and understand the role of the Human Resources department in the Leadership Talent Review process. We will write a custom essay sample on Leadership Talent Reviews or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page The textbook definition of â€Å"Human Resource Management encompasses those activities designed to provide for and coordinate the human resource of an organization. † (Byars, 2011), this definition also applies to the HR role in the Leadership Talent Review process. The Human Resources department is not responsible for independently and unilaterally designing, implementing, and operating the Leadership Talent Review process. Rather, the Human Resources department will provide advice, counsel, research and act as facilitators in the process. The Orlando Agency The Department of Defense agency located in Orlando, Florida has an end-strength of 1,200 employees. Its mission is to research, procure, develop, and ultimately provide state-of –the-art training devices for the United States military as well as, some foreign militaries. The employee professional categories are engineers, logisticians, contract specialists, project managers, staff, and administrative positions. It uses a formal Leadership Talent Review process. This agency â€Å"supports employee participation in Leadership Development Programs. There are internal; JLDP and NLDP programs and there are external programs. Mentoring is another focus area for this command and lots of communication and coordination is accomplished to educate the workforce about the benefits of the Mentoring program†. Journey Leadership Development Program The JLDP (Journey Leadership Development Program) is a program designed to support and enable the development of leadership skills at all levels of the organization and is geared to compliment our masters-level leadership program, the NAVAIR Leadership Development Program (NLDP). The program has a suggested 1-2 year completion program length and does not guarantee promotions, awards, or bonuses† (Commander Naval Air Systems Command, 2011). The JLDP is designed to develop employees in the lower mid-level paygrades. It requires the employee to submit an application and be accepted upon review. NAVAIR Leadership Development Program NLDP (NAVAIR Leadership Development Program) is the name of the headquarters version of a Leadership Talent Review. It is a voluntary program that requires each applicant to submit a very extensive application that hinges on the essay portion. Although it is voluntary, occassionally there are employees that show exceptional potential and are highly encouraged to apply. It is open to personnel in the upper mid-level pay grades. â€Å"The NLDP consists of two tracks – the Management Leadership Track and the Continuous Process Improvement (CPI) Leadership track. Both focus on leadership, and specifically, developing you as a leader. As a core value of this organization, continuous process improvement is a leadership responsibility at every level in NAVAIR. That’s why, in the CPI track, participants will work side-by-side with master black belts on high-profile projects our senior leaders choose and fully support. Along the way, you’ll earn your own black belt certification. For leading and managing complex teams, the NLDP’s Management Leadership track focuses on executive core qualifications (ECQs) and extended rotational assignments, as well as Project Sponsor or Green Belt training. Each program has both CPI and leadership training components. Participants are committed to learning a broad range of leadership, management, and productivity improvement skills. Both tracks share common Leadership Development courses. Both program components also require each person to have a formal mentor to offer career advice and guidance along the way. This program does not guarantee promotions, awards, or bonuses. † (Commander Naval Air Systems Command, 2009) The Management Leadership Track takes three to five years to complete (part time). The Continuous Process Improvement (CPI) Leadership Track takes two to three years to complete (full time). The Headquarters Command in Patuxent River, Maryland that the Orlando agency reports to, reviews all the applications and makes a determination as to who is accepted into the program. The NLDP selection board convenes annually at the headquarters location. It is composed of executive level management personnel. The board reviews applications submitted from personnel that belong to headquarters and all of its subordinate agencies. The number selected each year is determined by the amount of budget available to fund the selectee’s training requirements through the entire program. The board is designed to be independent and advocating for or against any of the applicants is not part of the process. Subordinate agencies are not entitled to board representation. However, the board does attempt to select candidates in equitible numbers from all the subordinate agencies. Although, for completing the program the selectees are not promised a promotion, raise, or a bonus, it is past program graduates that are typically selected for strategic and key upper-level management positions. iMentor Program The iMentor program is a mentoring program open to all employees at all levels. An employee reviews a list of mentors and makes a selection and upon mutual agreement; mentor and protege’ are teamed up. The purpose as stated in the handbook is, â€Å"To enhance mission effectiveness and productivity through the promotion of employee personal and professional development: enhance knowledge transfer, produce higher retention rates, improve employee morale, and yield greater promotion potential. † (Naval Air Warfare Center Training Systems Division, 2012). Although the iMentor program is not a part of the JLDP or NLDP program it is a program that can set an employee onto the path of professional development. Current Trends in Leadership Talent Reviews There are several ways for an organization to approach the Leadership Talent Review process. One way would be for Top Management to engage the organization’s own Human Resources department to interactively work with management to design a program. An organization could outsource the process, with management participation. Another way would be for management to develop a process independent of the Human Resources department and without outside consultants that specialize in this kind of work. The last option would not be advisable because management may not be aware of the laws and regulations governing employee relations, diversity in the workplace, as well as many other areas of employment law. Leadership Talent Review Process Overview The first step is to establish a board, with the full support of the organization’s top leader; the Chief Executive Officer, President, etc. Decide how often the board will meet and the purpose and agenda of each meeting. Establish the criteria for consideration. Create a list of employees that are being nominated to the review process. Establish groups of employees with leadership potential with respect to their current position and future potential. The review board should examine each of the employees and assess their talent potential. Once the review of talent is complete, the employees identified for future leadership potential should be placed into a development program. If the Leadership Talent Review process has been successful it should feed into the organization’s succession planning so, that as employees leave the organization there is an existing known quantity of fully developed employees ready to take their place. Smiths Group, 2012) Establishing the Leadership Talent Review Board Establishing a Leadership Talent Review Board is the first step in the review process. It is important to select members that are diverse professionally, culturally, and from different business units. Board members should be mature both emotionally and professionally. The wrong type of personalities on the board can create problems and impede the progress of the board’s agenda. Some examples are as follows: 1. â€Å"The used car saleswoman shows up prepared to â€Å"sell† every one of her employees. 2. The defense attorney, â€Å"I object†! Each possible fault is torn apart and disputed, just like Johnny Cochran and a glove that doesn’t fit. 3. Your Grandmother, everybody’s just wonderful, and nobody could possibly have any weaknesses. 4. The toe tapper has better things to do than to sit around and talk about damn people.

Is Self

Discussion of the adaptations of plants Essays

Discussion of the adaptations of plants Essays Discussion of the adaptations of plants Paper Discussion of the adaptations of plants Paper Essay Topic: Discussion Salt marshes are intertidal ecosystems, surrounded by land and open to the sea by way of an estuary (Pomeroy Wiegert 1981). As a result salt marshes are constrained, by silt and saline water, to the type of communities it can sustain (Ranwell 1972). However because of the tidal nature of these ecosystems and the presence of many migratory birds we find some of the the most widley distributed plant species in the world (Ranwell 1972). The habitat is typically high in phosphates but low in nitrogen. Sulphur washed in from the sea collects in the soil and during dry periods lowers the soil pH (Chapman Reiss 2000). Essentially the main problem for salt marsh plants is that salt marsh ecosystems are perminantly waterlogged by seawater. Land plants obtain oxygen for their roots by diffusion of oxygen found in air spaces in the soil. When soil is waterlogged, water displaces oxygen from the air spaces and reduces oxygen transport to as much as 1/300000 of its original value (www.biome.ac.uk).  Most land plants are used to water that has an osmotis potential close to zero, however salt marsh plant communities have to exist in water conditions of much lower osmotic potential, approximately -2 Mpa. Most land plants subjected to such low osmotic potentials would loose water to its environment and die (www.biome.ac.uk). It is the aim of this paper to discuss some of the common mechanisms which plants colonising salt marsh habitats have evolved to make effiecient use of what oxygen is available and be able to exclude salt and absourb water or excrete any excess salt that is absourbed as a result, with reference to specific salt marsh species.  Salt-marsh plants are halophytes (Gr halos:salt + phyton:plant), meaning they can tolerate excessive salinity levels (e.g. 0.5% NaCl), and have characteristics of both terrestrial and marine environments (Pomeroy Wiegert 1981). The salinity may vary and depends on the structure of the marsh, rainfall, and how often it floods (Chapman and Reiss 2000). If rainfall is high the marsh is washed of some of its salinity and will be colonised by different species such as Limonium spp. (sea lavender) and Triglochin spp. (arrow grass) (Chapman and Reiss 2000).  Grasses and rushes, such as Spartina spp. Juncus spp. retrospectively, dominate salt marsh communities, however in the lower, muddy levels of salt marshes pioneer species such as Salicornia europaea are more common (Rose 1981) (Chapman and Reiss 2000). Many of the plants are terrestrial species and in the upper parts of the marsh, where salinity concentrations are prodominantly affected by the amount of rainfall and not tidal influences, soils similar too more obvious terrestrial habitats are witnessed (Pomeroy Wiegert 1981) (Ranwell 1972).  Plants found in more northenly located salt marshes tend to be more tollerant of higher salinities, e.g. Spartina anglica can tolerate salinities up to twice that of sea water (Ranwell 1972).  Salt marshes have a particularly low osmotic potential due to its high sodium chloride concentration. To prevent excess loss of water and to obtain water from its environment it is vital that plants maintain a lower internal osmotic potential than that of its external environment (Purvis 2001). This is a problem for non-halophytes at concentrations 0.05 M (1/10 sea water). However halophytes, subject to sea water (0.5 M), can develop internal osmotic potentials greater than 20 bars (Ranwell 1972).  There is also the problem for plants living in saline environments of the high toxicity of Na and Cl both found in high concentrations in salt marshes (Purvis 2001).  High external osmotic potential influences excess ion accumulation in the tissues of plants, resulting in irregular metabolism and for this reason plants living in salt marshes have to be highly selective in ion uptake. High external osmotic potential also has the effect of reducing plant growth, transpiration rate, water availability, and uptake of essential minerals (Ranwell 1972). No other toxic substance, worldwide, restricts plant growth more than sodium chloride (Purvis 2001). Salt marshes, like any other habitat have sub-habitats e.g. emergence marsh level, submergence marsh level, or tidal flat, which all present relatively different growing conditions for the species that occupy them. As a result we find plants that have preferences to these zones and hence have adapted a diverse array of methods to contend with the conditions the different zones subject them to. These adaptations and environmental preferences also affect limits of such things as growth, age, and clonal size (Ranwell 1972). Adaptation to saline environments has occurred in Salicornia so much so that not only can members of this species tolerate high NaCl concentrations but the ability to persist in fresh water environments has all but been lost (Ranwell 1972).  There are four different methods in which halophytes have adapted to various external osmotic potentials in order to maintain normal metabolic activities. They are ion selection, extrusion, accumulation, and dilution, of which more than one may be exhibited by any one plant (Ranwell 1972). The vast majority of salt marsh plant species are perennials with only few annuals present and confined to distinct salt marsh sub-habitats, such as Salicornia sp. and Atriplex sp. located in the pioneer and strandline zones respectively (Ranwell 1972).  The distinction that few annuals have adapted to a salt marsh environment led Chapman to describe it as a Hemicryptophyte (herbs with buds at soil level, protected by the soil itself or by dry dead portions of the plant) area (Ranwell 1972) (Thain Hickman 2000). One shared adaptation that most halophytes possess is they accumulate Na Cl ions and transport them to their leaves. The ions are stored in leaf cell vacuoles increasing the salt concentration in the tissues of halophytes and hence lowering its osmotic potential (Purvis 2001). This brings us back to an earlier statement that it is vital for plants living in saline environments to maintain a lower internal osmotic potential than that of its external environment in order to prevent water loss and so water may be taken up more effectively. An important scientific breakthrough in 1999 located a gene in the non-halophyte Arabidopsis which encodes for a Na/H ion antiport protein in the tonoplast and enables sodium uptake (Purvis 2001). Although this plant is not a common halophyte found in salt marsh environments it does help to understand how plants may evolve different methods to living in these environments.  Another adaptation of halophytes which reduces the risk of poisoning by excessive accumulation of NaLC is the formation of salt glands in their leaves. Salt, extracted by the glands, collects on the leaf surface and is removed by wind or rain. Osmotic potential in the leaf will inevitable become more negative as salt is excreted by the salt glands; this generates an increase in the osmotic potential gradient thus enabling the leaf to obtain water from the root more readily (Purvis 2001). The amino acid proline, is often stored in the vacuoles of halophytes which acts to lower the plants tissues osmotic potential (Purvis 2001).  The saline nature of a salt marsh makes it particularly difficult for plants to obtain water. For this reason a common characteristic of halophytes is succulence, which acts as a water reserve. This water reserve can be used when NaCl concentrations are high, e.g. evaporation in the soil during low tide.  Many succulent halophytes use crassulacean acid metabolism, a metabolic pathway which allows plants to store CO2 at night and then photosynthesis during the day with stomata closed. Reversed stomatal cycles also allow halophytes to conserve water by closing them during daylight periods (Purvis 2001). Damage by wave action is a serious threat to plants living in certain zones of the salt marsh; therefore many species have morphological adaptations as a result. Salicornia for example presents minimum leaf appendages by reducing to a phylloclade form, however it still maintains adequate photosynthetic surface for the high light level habitat in which it inhabits (Ranwell 1972). Water-logging is a characteristic of most salt marshes, particularly in the lower zones and as a result oxygen diffusion rates are low. During spring and summer algal blooms e.g. Pleurosigma colonize high level tidal flats and produce millions of small oxygen bubbles on the surface of the water-logged mud. Salicornia take advantage of the better conditions with regards to oxygen availability by germinating in April May with most of its growth occurring during the summer months (Ranwell 1972).  This is more obviously an ecological adaptation to saline environments; however this is just as important to understand as morphological adaptations are in plants existing in salt marsh habitats. Pappus hairs found on the seeds of Aster tripolium aid dispersal. The seeds tend to stick together as a result and more often than not are dispersed by water with only few dispersed by the wind. This type of dispersal adaptation allows Aster to colonize open ground, within the salt marsh, relatively quickly (Ranwell 1972).  Spartina has many specific adaptations to existing in more seaward zones of the salt marsh, which allows it to out-compete most other species for these sub-habitats. Spartina has been successful in these zones due to a type of polyploidy which promotes rapid growth, large size, and high fertility. High phenotypic plasticity also allows Spartina to take advantage of this zone by elongating its stems (as much as 15 cm yearà ¯Ã‚ ¿Ã‚ ½Ãƒ ¯Ã‚ ¿Ã‚ ½) to penetrate aggregating mud in both pioneer and mature salt marshes (Ranwell 1972). Other adaptations that enable Spartina to successfully colonise more seaward zones include large seeds with substantial food reserves, rapid shoot root growth, deep anchor roots, and shoots well supplied with air spaces (Ranwell 1972). In conclusion Salt marsh habitats are intertidal ecosystems sustaining widley distributed plant communities which can exist in an environment which is typically high in phophates, low in nitrogen, has a low soil pH, suffers from waterlogging, and a low osmotic potential.  The main problems for salt marsh plants is low oxygen diffusion rates and a low osmotic potential due to daily waterlogging by sea water.  High osmotic potential results in reduced plant growth, transpiration rate, water availability, and uptake of essential minerals and due to the toxicity of Na Cl, excessive accumilation can result in irregular metabolism. All salt marsh plants are halophytes, tolerating excessive saline levels (0.5% NaCl), with Spartina anglica for example capable of tolerateing salinities twice that of sea water.  To prevent excessive water loss and to obtain water salt marsh plants maintain a lower internal osmotic potential than that of its external environment.  Halophytes have evolved four different methods to maintain normal metabolic activities in various external osmotic potentials; ion selection, extrusion, accumulation, and dilution.  Accumulation involves the plant transporting and storing Na Cl ions to their leaf cell vacuoles. Salt glands often found in the leaves of salt marsh plants extracts salt which collects on the leaf surface and is removed by wind or rain.  Succulence is a common characteristic of halophytes acting as a water reserve and can dilute high NaCl concentrations for example at low tide.  These methods are all effective in lowering internal osmotic potential and increasing the osmotic potential gradient thus enabling the leaf to obtain water from the root more readily.  Crassulacean acid metabolism allows halophytes to store CO2 at night and conserve water during the daylight periods by photosynthesising with closed stomata. Ecological adaptation include for example adaptation by Salicornia to low oxygen diffusion rates takes advantage of millions of oxygen bubbles produced on the surface of waterlogged mud in high level tidal flats by algal blooms.  Morphological adaptations include for example adaptation by Salicornia to reduce damage by wave action by reducing to a phylloclade form thus presenting minimum leaf appendages.  It is clear that most of these evolved adaptations are a result of plants attempting to survive in an environment which is subject to especially low oxygen diffusion rates and in particullay low osmotic potentials. Reference List www.biome.ac.uk  Chapman, L.J. M.J. Reiss (2000) Ecology principals applications, University press; Cambridge  Pomeroy, L.R. R.G. Wiegert (1981) The ecology of a Salt Marsh, Springer-Verlag Inc; New York  Purvis, W.K., D Sadava, G.H. Orians, H.C. Heller (2001) Life: The science of biology, Sinauer associates; Massachusettes

Supporting a difficult point Essay Example | Topics and Well Written Essays - 750 words

Supporting a difficult point - Essay Example Performance anxiety over fixed tests and graded assignments inhibits high level thinking among students. Grading system usually associated with lot of projects, assignments and seminars. Since student’s performance will be rated in all of the above while deciding the grades, students will much tensed and they will not get opportunities for mental relaxation. The mental fatigue will be crucial factor associated with such projects and assignments. I know certain students engaged in getting the assignments done by others in order to reduce their work load. This habit will actually against the principles of the grading system. Students will learn nothing from such assignments done by others. The anxiety over grades will prevent students from developing as intellectual abilities. Students will concentrate more on their grades rather than anything else. Grades will create discrimination feeling among the students. Those who have secured ‘A’ grade will treat the ‘B’ or ‘C’ grade people as fools. This will result in, students losing interest in their studies and the classes. This inferiority will create desperations and frustrations among them. I know two persons who are teaching in a college. Both of them are teaching the same subject, but students are interested in the lecture classes of one more than the other. Interestingly the lecturer, whose classes labeled as boring by the students, secured much higher grades than the other lecturer during his studies. It clearly showed that grading system is not at all a reflection of abilities or intellectual level. In most of the universities grading will be done in a biased manner. Professors will have likes and dislikes upon certain students and while doing the internal assessment they will consider all such things. I have twice victimized while studying for my Bachelor course and Post Graduation course. During my Post Graduation studies one