Marine Phytoplankton Essay Example for Free

Marine Phytoplankton Essay Phytoplankton From Wikipedia, the free encyclopedia Jump to: navigation, search Diatoms are one of the most common types of phytoplankton. Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek words cpur?v (phyton), meaning plant, and TIXay? «?q (planktos), meaning wanderer or drifter. [l] Most phytoplankton are too small to be individually seen with the unaided eye. However, when present in high enough numbers, they may appear as a green discoloration of the water due to the presence f chlorophyll within their cells (although the actual color may vary with the species of phytoplankton present due to varying levels of chlorophyll or the presence of accessory pigments such as phycobiliproteins, xanthophylls, etc. ). Contents [hide] * 1 Ecology * 2 Aquaculture * 3 Blooms * 4 See also * 5 References * 6 External links [edit] Ecology Phytoplankton are the foundation of the oceanic food chain. Of these, the best known are dinoflagellate genera such as Noctiluca and Dinophysis, that obtain organic carbon by ingesting other organisms or detrital material. The term phytoplankton encompasses all photoautotrophic microorganisms in quatic food webs. Phytoplankton serve as the base of the aquatic food web, providing an essential ecological function for all aquatic life. However, unlike terrestrial communities, where most autotrophs are plants, phytoplankton are a diverse group, incorporating protistan eukaryotes and both eubacterial and archaebacterial prokaryotes. There are about 5,000 species of marine phytoplankton. [8] There is uncertainty in how such diversity has evolved in an environment where competition for only a few resources would suggest limited potential for niche differentiation. [9] In terms of numbers, the most important groups of phytoplankton include the diatoms, cyanobacteria and dinoflagellates, although many other groups of algae are represented. One group, the coccolithophorids, is responsible (in part) for the release of significant amounts of dimethyl sulfide (DMS) into the atmosphere. DMS is converted to sulfate and these sulfate molecules act as cloud condensation nuclei, increasing general cloud cover. In oligotrophic oceanic regions such as the Sargasso Sea or the South Pacific Gyre, phytoplankton is dominated by the small sized cells, alled picoplankton, mostly composed of cyanobacteria (Prochlorococcus, Synechococcus) and picoeucaryotes such as Micromonas. [edit] Aquaculture Diagrams of some typical phytoplankton. Main article: Algaculture Phytoplankton are a key food item in both aquaculture and mariculture. Both utilize phytoplankton for the feeding of the animals being farmed. In mariculture, the phytoplankton is naturally occurring and is introduced into enclosures with the normal circulation of seawater. In aquaculture, phytoplankton must be obtained and introduced directly. The plankton can either be collected from a body of water or foodstock for the production of rotifers[10], which are in turn used to feed other organisms. Phytoplankton is also used to feed many varieties of aquacultured molluscs, including pearl oysters and giant clams. The production of phytoplankton under artificial conditions is itself a form of aquaculture. Phytoplankton is cultured for a variety of purposes, including foodstock for other aquacultured organisms[10], a nutritional supplement for captive invertebrates in aquaria. Culture sizes range from small-scale laboratory cultures of ess than 1 L to several tens of thousands of liters for commercial aquaculture[10]. Regardless of the size of the culture, certain conditions must be provided for efficient growth of plankton. The majority of cultured plankton is marine, and seawater of a specific gravity of 1. 010 to 1. 026 may be used as a culture medium. This water must be sterilized, usually by either high temperatures in an autoclave or by exposure to ultraviolet radiation, to prevent biological contamination of the culture. Various fertilizers are added to the culture medium to facilitate the growth of plankton. A culture must be aerated or agitated in some way to keep plankton suspended, as well as to provide dissolved carbon dioxide for photosynthesis. In addition to constant aeration, most cultures are manually mixed or stirred on a regular basis. Light must be provided for the growth of phytoplankton. The colour temperature of illumination should be approximately 6,500 K, but values from 4,000 K to upwards of 20,000 K have been used successfully. The duration of light exposure should be approximately 16 hours daily; this is the most efficient artificial day length[10]

Ageism in the Workplace Essay -- Age Discrimination

Age discrimination has long been present in society due to the rapid development happening around us. According to Farney, Aday & Breault (2006), this era of ageism is defined as "discrimination against any age group", but it often is pointed to age discrimination among adults which is slowly causing a negative effect for them in the workplace. In the workplace, adults with more experience and longer history behind them are targets of this ageism belief that companies and employers tend to have (Farney, Aday, & Breault, 2006). They are shunned and even fired in favor of accepting new and fresh faces for the company they have worked for. Unknown to most companies and employers, this notion of favoring the young and banishing the old can cause them a lot of losses in terms of business, economy and individually if this continues on. For this paper, it is my fervent belief that this concept of age discrimination in the workplace can be stopped if there is a proper decorum on addressing t he importance of older employees in the workforce and the discussion of the possible consequences of continuing this age discrimination practice and how revise the current recruitment system so that employees are given equal opportunities and not fire them just because of their ages. The problem of age discrimination especially in the older generation is not a new issue as it has been around for quite a long time. Segrave (2001) noted that most workers are deemed old if they reach their forties in the early nineteenth century. Employers and companies would already start firing people just because of this particular notion on age. Employees find this idea ludicrous and insulting as they are judged just because of their age and some would file charges ... ...younger generation would also feel this stereotyping, discrimination and prejudice once they step in the age where they can be classified as part of the older generation. The problem of age discrimination is a long cycle of problems that all members of society would face in some point of their lives. Now that everyone is taking good interest of worker rights, they would realize that this old notion of age discrimination is still happening and they would stop at nothing to get rid of the problem before they experience it themselves. Once this problem is resolved and eliminated, not only would the older generation benefit from it but also the society in general. Everyone must be given a chance to work on their professions even in their golden years, as long as they are happy and stress free because of the lack of discrimination on their age, we should let them be.

The Impact of Local Television in Today’s Society

Local Television in Today's Society Since the early 1940's, it has been clearly evident that television has played a crucial role in the way people receive and perceive news media on a day to day basis. According to State of the News Media, viewership and ratings have drastically changed over the years and as of 2012, it is suggested that it is in large part due to the pressing and irreversible shift towards social media.Now our country not only relies on our friendly local newscasters to fill us in on the weather or breaking news irst thing in the morning, but also on the latest KRQE tweet on Twitter or status update on Facebook. Our world is turning digital and as hard as many may try to stop it, there is no denying that a future in news will rely heavily on the efficiency and effectiveness of social media. So where does this leave our local television stations and ultimately, how will this digital frenzy effect their overall viewership, ratings and longevity?This is the prominent concern in our local news media world today and a question that must be discussed and actively researched to ensure the future of local elevision news. Throughout the course of this semester, the students in this Media Management course have had the opportunity to pick the brains of various news anchors, producers, directors, and Journalists to question and investigate this shift from both print media and local television, to our growing reliance on internet and various social networking sites.Each of our guests was forced to explore the same question: In a time of slipping credibility and growing opinion, how do you succeed in the digital era while maintaining values and traditions of great Journalism that rought us here in the first place? With no surprise, each speaker responded with a similar statement. The gist being that as a society, we must, as a whole, focus on seeking the truth behind any story. We must provide valid, reliable and timely information that pertains and relat es to the lives of every member in our community and remain a trustworthy source of news for years to come.We must place precedence on social responsibility. Seems a lot easier said than done considering there has been a noticeable decline in local TV news viewership since 2007. And lthough there was a slight increase in 2011, the mostly steady decline has been cause for great concern in the news world. While reading the substantial amount of information that State of the News Media provided on this issue, it was apparent that network and local stations alike are predominantly losing viewers (or in some rare cases reaching a time of stabilization) in both primetime television spots as well as in nontraditional time slots.The research suggests that although there is the occasional increase in viewers during times of national or worldwide distress, there is indeed a uantitative measure proving simply a sta bilization ot local news audiences in specific time slots (no increase) versus the drastic decline that was evident beginning in 2007. However, this ‘improvement' was not substantial enough to propose that local TV news has entered a period of new audience growth. According to SNM, â€Å"viewership of network affiliates was up for newscasts in both the morning (5 to 7 a. m. ) and late evening (11 p. m. when averaged across all sweeps periods studied. In the early evening time slot (5 to 7 p. m. , viewership was down slightly. † Delving a little deeper into the sweeps periods offered a clue to at least one reason behind the improvement – there has been higher interest in the news (for example the coverage of the chaos, rebellion, and distress surrounding Egypt and Libya earlier in the year or the 2012 Presidential election. ) But breaking news or continuous coverage of a significant event may not always dominate the airwaves considering there are times when news is slow and not as easily accessible.At that point reporters must rely on heir o wn investigative skills and creative thinking to find their own stories to dissect and examine. These facts were reiterated by a large number of our guest speakers in class including Alex Tomlin, Bill Anderson, Doug Fernandez and Jessica Garrate. They all made it a clear point to discuss the importance of understanding the average news consumers' daily routine, the most critical time of day that any one individual can be reached and what it is that truly attracts a news consumer to a particular station. That is the indeed the key to success for any local station.Understand the consumer and their wants and needs, take initiative on finding imperative stories regarding our community, and consistently provide viewers with the most up to date and relevant news possible while maintaining a good reputation by being credible, reliable and original. In todays news world, this in many instances means Jumping on that social media bandwagon and making the decision to provide consumers with pla y by plays via the internet. â€Å"Almost every station in the country now has a Facebook page, according to the annual RTDNA/Hofstra survey, and almost 90% have t least one Twitter feed. (SNM, 2012) This move to digital news has proven to be in some cases effective, and in others somewhat irrelevant to the success of local stations (or newspapers) as mentioned by Bill Anderson, general manager of KRQE, and Dan Mayfield, Sr. writer for NM Business Weekly. However, although results of viewer increase due to social media is not definitive; it has great potential to become a positive influence for any news team because social media can encourage consumers to sample any station's newscast.And once that seed has been planted, it becomes the responsibility of the news team to deliver a quality show that maintains that viewers' interest. Alex Tomlin, news reporter and correspondent for KRQE, discussed in great detail the value of delivering hard and entertaining news, without focusing on the trend of social media. She mentioned briefly how a reliance on networking sites is viewed in the news world as a method of being lazy and therefore unreliable because it is difficult to attribute any fact to the alleged statements being made.

How to Make a Delphi Login Form

The MainForm of a Delphi application is a form (window) that is the first one created in the main body of the application. If you need to implement some kind of authorization for your Delphi application, you might want to display a login/password dialog before the main form is created and displayed to the user. In short, the idea is to  create, display, and destroy the login dialog before creating the main form. The Delphi MainForm When a new Delphi project is created, Form1 automatically becomes the value of the MainForm property (of the global Application object). To assign a different form to the MainForm property, use the Forms page of the Project Options dialog box at design time. When the main form closes, the application terminates. Login/Password Dialog Lets start by creating the main form of the application. Create a new Delphi project containing one form. This form is, by design, the main form. If you change the name of the form to TMainForm and save the unit as main.pas, the projects source code looks like this (the project was saved as PasswordApp): program PasswordApp; uses Forms, main in main.pas {MainForm}; {$R *.res} begin Application.Initialize; Application.CreateForm(TMainForm, MainForm) ; Application.Run; end. Now, add a second form to the project. By design, the second form thats added gets listed in the Auto-Create Forms list on the Project Options dialog. Name the second form TLoginForm and remove it  from the Auto-Create Forms list. Save the unit as login.pas. Add a Label, Edit, and Button on the form, followed by a class method to create, show, and close the login/password dialog. The method Execute returns true if the user has entered the correct text in the password box. Heres the full source code: unit login; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; type TLoginForm class(TForm) LogInButton: TButton;pwdLabel: TLabel;passwordEdit: TEdit;procedure LogInButtonClick(Sender: TObject) ; publicclass function Execute : boolean;end; implementation{$R *.dfm} class function TLoginForm.Execute: boolean;beginwith TLoginForm.Create(nil) dotry Result : ShowModal mrOk; finally Free; end;end; procedure TLoginForm.LogInButtonClick(Sender: TObject) ;beginif passwordEdit.Text delphi then ModalResult : mrOK else ModalResult : mrAbort; end; end. The Execute method dynamically creates an instance of the TLoginForm and displays it using the ShowModal method. ShowModal does not return until the form closes. When the form closes, it returns the value of the ModalResult property. The LogInButton OnClick event handler assigns mrOk to the ModalResult property if the user has entered the correct password (which is delphi in the above example). If the user has provided a wrong password, ModalResult is set to mrAbort (it can be anything except mrNone). Setting a value to the ModalResult property closes the form. Execute returns true if ModalResult equals mrOk (if the user has entered the correct password). Don't Create MainForm Before Login You now only need to make sure the main form is not created if the user failed to provide the correct password. Heres how the projects source code should look: program PasswordApp; uses Forms, main in main.pas {MainForm}, login in login.pas {LoginForm}; {$R *.res} beginif TLoginForm.Execute thenbegin Application.Initialize; Application.CreateForm(TMainForm, MainForm) ; Application.Run; endelsebegin Application.MessageBox(You are not authorized to use the application. The password is delphi., Password Protected Delphi application) ; end;end. Note the usage of the if then else block to determine if the main form should be created. If Execute returns false, MainForm is not created and the application terminates without starting.