Saturday, November 24, 2012

DNA extraction


DNA  is a double-stranded molecule twisted into a helix
 Each spiraling strand, is comprised of a sugar-phosphate backbone and attached bases.
o Complementary strands are connected by non-covalent hydrogen bonding between paired bases, adenin (A) with thymine (T) and guanine (G) with cytosine)
- Pyrimidine: T,C
- Purine: A, G
 

ccpp



Contagious caprine pleuropneumonia (CCPP) is a cause of major economic losses to goat production in at least 30 countries in Africa and Asia containing a total goat population of more than 300 million. Classical, acute CCPP is caused by Mycoplasma capricolum subspecies capripneumoniae (Mccp) (MacOwan and Minette 1976) originally known as Mycoplasma F38. This mycoplasma was first isolated from the lungs of goats with pleuropneumonia in Kenya and demonstrated to cause CCPP. The disease is characterised by fibrinous pleuropneumonia with increased straw-coloured pleural fluid. Morbidity and mortality rates may reach 100% and 80%, respectively.
In the lab, to detect CCPP in gaot, cow, take  one drop serum sample 
of  goat in the plate like in picture and one drop of ccpp antigen, then mix
the postive result, you see like small white sand like in this picture.


 

 

Eutrophication


 
Fish Kill in the <a href='/article/Salton_Sea' title='Salton Sea' class='mw-redirect'>Salton Sea</a> as a result of eutrophication.Eutrophication: The process by which a body of water acquires a high concentration of nutrients, especially phosphates and nitrates. These typically promote excessive growth of algae. As the algae die and decompose, high levels of organic matter and the decomposing organisms deplete the water of available oxygen, causing the death of other organisms, such as fish. Eutrophication is a natural, slow-aging process for a water body, but human activity greatly speeds up the process.
 
 
Algal bloom in Orielton Lagoon, Australia, 1994. (Photo by Geoff Prestedge)


The runoff of nitrate and phosphate into lakes and streams fertilizes them, and causes accelerated eutrophication  or enrichment of the waters.

Eutrophication  occurs as lakes age. However, human-caused, accelerated eutrophication (called "cultural eutrophication") occurs more rapidly, and causes problems in the affected water bodies, as described below. It is estimated that 50-70% of all nutrients reaching surface water (principally N and P) originate on agricultural land as fertilizers or animal waste.

 

Communication process


Communication is the exchange and flow of information and ideas from one person to another; it involves a sender transmitting an idea, information, or feeling to a receiver .Effective communication occurs only if the receiver understands the exact information or idea that the sender intended to transmit.

Communication is a process of exchanging verbal and nonverbal messages. It is a continuous process. Pre-requisite of communication is a message. This message must be conveyed through some medium to the recipient. It is essential that this message must be understood by the recipient in same terms as intended by the sender. He must respond within a time frame. Thus, communication is a two way process and is incomplete without a feedback from the recipient to the sender on how well the message is understood by him.

 

The main components of communication process are as follows:

1.Context - Communication is affected by the context in which it takes place. This context may be physical, social, chronological or cultural. Every communication proceeds with context.

2. Sender is a person who sends the message. A sender makes use of symbols (words or graphic or visual aids) to send the message and produce the required response. The verbal and non-verbal symbols chosen are essential in ascertaining interpretation of the message by the recipient in the same terms as intended by the sender.

 

 

3. Message - Message is a key idea that the sender wants to communicate. It is a sign that elicits the response of recipient. Communication process begins with deciding about the message to be conveyed.

 

4. Medium - Medium is a means used to exchange / transmit the message. The sender must choose an appropriate medium for transmitting the message else the message might not be conveyed to the desired recipients. This choice of communication medium varies depending upon the features of communication. For instance - Written medium is chosen when a message has to be conveyed to a small group of people, while an oral medium is chosen when spontaneous feedback is required from the recipient as misunderstandings are cleared then and there.

 

5. Recipient is a person for whom the message is intended / aimed / targeted. The degree to which the decoder understands the message is dependent upon various factors such as knowledge of recipient.

 

6. Feedback is the main component of communication process as it permits the sender to analyze the efficacy of the message.  Feedback may be verbal (through words) or non-verbal (in form of smiles, sighs, etc.). It may take written form also in form of memos, reports, etc.

 For more information see:



 

 

 

 

 


 

 

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