Computer Studies Made Simple : Keyboard and its parts

Keyboard:

This is the most commonly used input device.

The buttons on the keyboard are termed as keys.

The keys maybe alphabetical,numerical and fumction keys.

Most keyboards are in QWERTY format and are called QWERTY keyborads.

Parts of keyboard:

A QWERTY and a normal keyboard has the following main parts:

1.Function keys

2.Main keyboard

3.Numeric keys

1.Function Keys:

These are used to perform special functions depending upon the software being used in the computer.

2.Main Keyboard:

This includes the alphabetical keys.  

3.Keys with special functions:

Caps Lock Keys:

When this key is pressed,the characters appear in uppercase.

Shift Keys:

This key when pressed in combination with other keys produce upper case letters and upper symbols shown on certain keys.

Control Keys:

The control key when pressed with other keys can execute different commands .For example pressing Ctl with P s used to print a page.

Alt Key

This is used with other keys to execute a command.

Enter Key:

This is used to move the cursor to the next line usually at the end of a sentence or paragraph.

Escape Key:

This is used to terminate a current task or command.

Numeric Keys:

They are located on the right side of key board.

If the Num lock is on,they canbe used to enter numbers from 0 to 9 and combinations.

With Num lock off,they are used to move cursor on the page

Dermatology Made Simple : Eczema ( Dermatitis) Definitions and Classification

Eczema

Eczema or Dermatitis is the inflammation of the skin.

It is characterized by :

Skin dryness,

Scales and

Skin rashes.

It has a number of causes

Classification

Eczema can be classified as below :

Endogenous Eczema :

This includes :

Atopy/ Allergy

Discoid

Seborrhoea

Exogenous / Contact:

This includes :

Allergic

Photosensitivity

Irritants

Secondary:

Includes Infections.

Clinical Features:

Eczema can present withacute or chronic onset

Acute cases are characterized by redness,vesicles and exudation.

Chronic cases are characterized by scales,dryness and thickening of the skin.

Eczema is itchy and with time there maybe loss of skin surface,secondary bacterial infection.

Chronic changes can also cause loss and change of skin pigmentation

Computer Studies Made Simple : Input of Data,Input Methods and Devices

Input:

Any data or instructions that are given to the computer is termed as Inpusdt.

Methods of Entering Input into a computer:

There are two methods of entering data and instructions into the computer:

1.Direct input:

In this type of input,the data goes directly into the computer from the source.

For example: speaking directly into the computer using a microphone.

The devices used for direct data input are called as Source Data Input Devices.

Examples of Source Data Input Devices include:

Microphones

Digital Cameras

2.Indirect input :

In this method,some intermediate processing is involved in conveying data to the computer.

Examples include use of keyboard.

Input Devices:

This is hardware part of computer that is used to enter data and instructions into a computer.

Input devices take data and instructions from the user and convert them into a form that canbe interpreted by the computer.

Examples of Input Devices include :

Keyboards

Mouse

Microphones etc  

Dermatology Made Simple : Systemic Treatment for Psoriasis

Systemic Treatment for Psoriasis

Should be initiated by experienced specialist dermatologists.

Indications:

1.Unstable inflamed psoriasis.

2.Widespread disease

3.Disease not responsive to topical or phototherapy.

4.Concomitant psoriatic arthropathy.

Types of Drugs used:

First Line include : Methotrexate and acitretin.

Others commonly used include:

Ciclosporin

Hydroxyurea

Azathioprine

Mycophenolate mofetil

Biological therapies :

Infliximab

Etanercept

Efalizumab

Adalimumab

Methotrexate:

Is given as once weekly injection or tablet.

Is used for Rx of unstable erythrodermic pustular psoriasis in acute setting and also maintenance therapy of 

chronic plaque disease.

Side effects:

Hepatotoxicity / liver Damage.

Bonemarrow suppression / Myelosuppression.

Acitretin :

Is a Vitamin A derivative.

Computer studies Made Simple : Types of Software

Software maybe divided into two main categories:

1.System Software

2.Application Software

1.System Software : 

This is a set of programmes that implements certain functions in a computer system.

 It also controls the operations of a computer system.

 It also controls the application of different hardware components for usage.

 It also sends instructions to the relevant hardwares to carry out their functiosn as per programme.

 Some examples of system software include: Device drivers and Operating Systems

2.Application Software : 

This software performs different applications on the computer. 

Types of Application Software: 

A.Customized Software: 

This application software is specifically designed for a particular organization in a way that it meets the requirements and needs of that organization.

B.Package Software: 

Also called as off the shelf software is a type of application software that is intended to be sold to the public and helps them organizing in their routine daily activities.

Examples of package software include: Micrsosoft word Excel Powerpoint Spread sheet Databases

Treatment of Psoriasis : Phototherapy

Phototherapy ncludes Ultraviolet Radiation A and B given to the sites affected by Psoriasis

Mechanism of Action:

Phototherapy acts by the following mechanisms:

1.Inhibition of production and releaes of  pro-inflammatory cytokines.

2.Induction of apoptosis of immune cells.

3.Reduction of Antigen presentin capacity of dendritic cells.

Usually phototherapy is given to patients with extensive disease and in those in which topical treatment has failed.

Duration lasts for approximately 6 to 8 weeks and  sessions are conducted 2 – 3 times / week.

A layer of emollient is usually applied on the skin and the therapy is given in special cubicles.

The dose and time of exposure is increased gradually as the treatment progresses.

Side Effects of Phototherapy:

1.Can cause increase susceptibility to skin cancers

2.Excessive dose can cause premature aging of skin

Contraindications:

1.Increased Photosensitivity

2.Albinism

3.History of skin cancer

4.Lupus erythematosus

5.Porphyrias.

Ultraviolet B is short wavelength therapy.

It canbe used in children and during pregnancy.

Ultraviolet A

This is long wavelength light.

It is given with oral or topical psoralen  as Psoralen + UV A called as PUVA.

It cannot be used during pregnancy.

Is used in thick plaque and wide spread psoriatic disease.  

Computer studies Made Simple : Information Technology

Information Technology :

Information technology is a technology that uses computing with high speed communication links to send information from one area to another.

Uses of Information Technology :

IT has helped in sending useful information among people living in different countries and continents of the world.

This helps in distant learning and enable people in different parts of the world to remain in contact with eachother.

It has allowed the information to be sent fairly quickly and as a result,the world has become a global village.

The information canbe conveyed in various forms such as text,videos or audio information.

Devices used in conveying information in IT Netwrok:

The various devices that are used to send information are as follows:

Mobile phone

Satellite

Fibre optics

I pads.

Useful Applications of Information technology

E – Commerce:

This means carrying out business using internet

Internet Banking:

Different banks allow their customers to use banking services online.It allows them to access their bank account at any time and even perform transactions and transfer money to other accounts.

M- Commerce:

Or mobile commerce means buying goods using mobile phones

Artificial Intelligence:

This refers to production of machines with ability to reason,and interpretation of sounds and vision and carrying out necessary action when stimulated using the above application.

Dermatology Made Simple: Management of Psoriasis : Topical Therapies

Topical therapies for Psoriasis

These treatments are applied directly to the skin surface.

These include:

Ointments

Creams

Lotions

Tars

Mechanism if action:

These treatments result in changes at and just below the skin surface.ie in epidermis and dermis.

Combination therapy is more effective than monotherapy.

Advantages of Topical treatments are as follows:

1.Cheaper form of therapy

2.No systemic side effects.

3.Easy to use as can be applied by oneself on diseased skin.

4.Effective in milder forms of disease

Disavdantages are:

1.Messy

2.Poor compliance

3.Decreased effectiveness of therapy with time.

4.Not effective in severe forms of disease.

Some characteristics of different forms of topical therapies:

Topical corticosteroids:

They reduce superficial inflammation within plaques.

They are applied on affected areas of the skin once or twice daily.

Are safe for use on face and flexural areas of skin.

Steroids of moderate intensity are most useful in chronic plaque psoriasis

Disadvantages:

1.Relapse occurs on cessation

2.Tachyphylaxis ( reduced potency on repeated use ) is observed.

Calcipotriol:

This is vitamin D analogue.

These are useful for mild to moderate plaque psoriasis.

Can cause mild irritation at site of application.

They are best used with other topical preparations.

Dithranol:

This is produced from araroba trees.

Is useful in chronic plaques psoriasis.

They stain skin and hair a purple brown color

They can cause irritation and burning of normal skin.

Strength varies from 0.1 % to 3 %.

Icthammol:

It is  a sulphur preparation.

It has anti-inflammatory properties.

Coal tar:

There are various coal tar preprations including ointments,pastes,paints,soaps and shampoo.

Coal tar preparations normalize keratinocyte growth patterns.

It is useful in chronic plaque psoriasis.

When combined with salicylic preparations,it is very effective for very thick plaques.

Emollients:

They prevent cutaneous fluid loss and relieve itching.

They restore function of skin as a barrier.

They are readily available and a cheap form of treatment.

Computer Studies Made Simple: Components of a computer

Computer:

A computer is a device or a machine that canbe programmed to accept data,process it into meaningful 

information and store it in memory as well.

Components of a computer:

A computer consists of the following components:

Hardware or structural part

Software 

The software instructs or directs the processing of input to output and the Hardware performs or executes 

the instructions.

Main Components in Computer Assembly

1.Input Devices:

These devices input data and intructions into the computer.

Examples of these devices include keyboard and mouse etc.

2.Processors:

This processes the data fed to the computer by the input devices

It is also called as CPU : Central Processing Unit

It consists of electronic circuits.

CPUs interpret and execute programme instructions.

Main memory stores the input data before it gets processed.It also stores the processed sdata before it is conveyed to the output device.

3.Output devices:

These devices display the processed data/information or output from a CPU

Examples of these devices include : Printer and computer/laptop monitor

4.Storage Devices:

Main memory stores data only temporarily

Storage devices store data permanently.These include Hard disk drive,CD Roms etc

Computer Studies Made Simple : Data,Information and Data Processing

Data:

Data is collection of facts and figures that have not been processed completely yet.

Data consists of numbers,pictures,characters and symbols.

Data is collected from a large number of sources.

Information:

The processed and meaningful data is called as Information.

Data Processing:

The process of converting data into meaningful information is termed as Data processing

Components of a Data processing System:

In any data processing system,data is the input and information is the output.

The basic steps of data processing are as follows

Input (Data)      à    Processing           à     Output (Information)

Dermatology Made Simple: Management of Psoriasis

Management of Psoriasis

It is important to assess and address the impact of disease on patient”s quality of life and its psychological effects.

Different forms of Psoriasis have different first choice treatment.

Facial Psoriasis:

Topical steroids

Guttate Psoriasis:

Topical steroids

Ultraviolet B Therapy

Flexural Psoriasis:

Topical steroids

Antifungals

Localized Stable Plaques:

Coal tar preparations

Topical steroids

Vitamin D analogues

Dithranol

Salicylic acid preparations

Extensive Stable Plaques:

Psoralens and Ultraviolet A Therapy PUVA

Acitretin

Ultarviolet B Therapy

Methotrexate

Cyclosporin A

Hdroxyurea

Biological Modalities (Antibodies)

Computer Studies Made Simple : Software and Hardware

Software:

Software is a set of instructions that tells a computer what to do.

A computer works according to the instructions written in the software.

In case of any errors are encountered,software has to be debugged.

Similarly if a problem still doesnot  get resolved,a software may need to be reinstalled

Hardware:

This term applies to the physical parts of a computer.Examples of these are keyboard and Mouse

Software is a set of instructions that tells the computer hardware what to do.

A hardware can not execute any function without a software.

Similarly,software cannot perfom without hardware and thus both are essential for each other.

In case of a problem,a hardware has to be repaired.

If problems persists despite repair,hardware has to be replaced.

Physics Made Simple:Electric Current Electromotive force and Ohm"s Law

Electromotive force:

The amount of energy supplied by the battery in pushing one coulomb of charge ( electrons) from its positive to its negative terminal through battery is known as the Electromotive force.

If one end A of a conductor is connected to positive terminal of a battery and the other end B is connected to negative terminal of battery,an electric field gets generated that leads to flow of current from A to B ie from a Higher to a Lower Potential.

In order for the current flow to be continuous,chemical processes in the battery pump the electrons to negative terminal B through the battery when they reach terminal A.

The electromotive force is the energy supplied by battery in pushing the electron from its positive to negative terminal.

Ohm”s Law:

The value of Current I passing through a conductor is directly proportional to the potential difference V applied across its ends,provided the temperature and the physical state of the conductor doesnot change.

V = I R

Where V is the voltage applied across the conductor ends

I is the current flowing through the conductor

R is the Resistance of the conductor.

Physics Made Simple : Electric Current

Electric Current

When electric charges are moving across any surface,we say electric current is flowing through that surface.

The rate of flow of electric charge through any cross sectional area is called Electric Current.

If Charge Q is passing through an Area A in time “t” second,then the electric current flowing through it would be I

I = Q/t

In SI (System International), the init of current is known as Ampere.

Electric charges are of two kinds : positive and Negative.

Electric current is produced due to flow of both positive and negative charges.

Conventional Current

Consider there is a metal cup.

A stream of positive charges is being injected into a metal cup.As there is a movement of electric charges taking place,we will say an electric current is flowing through upper cross sectional area of this cup.

The result of this movement is the amount of positive charge increases in he cup.

If we stop the injection of positive charges now and instead start to inject negative charges,the positive charges stored in electric cup would start getting neutralized.

In other words, the effect of flow of negative charges is the same as effect produced by flow of positive charges in opposite direction to flow of negative charges.

We can safely say that the current produced by the flow of negative charges is equivalent to a flow of current of an equal amount of positive charges in the opposite direction

This equivalent current of positive charges is known as conventional current.