Charge enclosed in incremental volume and Divergence theorem

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In this video, Gauss's law is applied to a general closed volume and a relation between volume and surface integration is found.






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Spotters in "Family Planning: Barrier Contraceptive Methods" for CFM & MPH students

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Design equations of Rectangular Microstrip Patch Antenna

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Following design equation can be used to calculate the width and length of rectangular microstrip patch antenna and simulation of 2.4 GHz inset-feed rectangular patch antenna can be found in follwing video.  Microstrip antenna with inset-feed line                           Part-1 Design step for the calculation of W and L Step-1 : To calcualte width 'W' use follwing formula Step-2:   Calculate the effective dielectric constant using formula below. Here    ' ε r '  is relative  dielectric constant of the material. 'h' is height of the substrate and W is the width of patch calculated in first step. Step-3:   Calculate ΔL using formula below. Step-4:   Calculate length of the patch using formula below. v 0    is speed of light in free space. Part-2 Feedline calculation Step-1:   Calculate the input impdedance of the patch using follwing formula. (Typically between 200  Ω  to 250  Ω. You can assume 225  Ω for simplic
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Spotters in "Hospital Waste Management" for CFM & MPH students

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 As per “Bio-medical Waste Management Rules, 2016”  1. Yellow Bin/ Bag: Type of Bag/  Container used:  Non-chlorinated  plastic bags Type of Waste:  1. Human Anatomical Waste A. Tissues, organs, body parts B. Foetus, Umbilical stump, placenta 2. Animal Anatomical Waste:  Tissues, Organs, body parts 3. Soiled Waste:  items contaminated with blood and body fluids A. Dressings, sponges, gauze B. Plaster casts C. Cotton swabs D. Blood bags E. Infected gowns, mask, shoe covers, cap 4.  Expired or Discarded  Medicines:   including antibiotics (except cytotoxic) 5. Chemical Waste: A. Discarded disinfectants, Cleaning agents B. X-ray film developing liquid, Infected secretions C. Aspirated body fluids, Liquid from laboratories 6. Microbiology, Biotechnology, and other clinical  lab waste 7. Chemical Liquid Waste Yellow bin/ bag with the cytotoxic label: 1. Used, discarded, and expired cytotoxic drugs whether in plastic vaccutainers, syringes, glass  vials, ampoules, glass bottles. The containe
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  1. Sanitary well: Important points: Location: Not less than 15 m (50 feet) from likely sources of contamination & at a higher elevation. Not more than 100 m from houses Lining: Should be made up of bricks/ stones & cement up to a depth of at least 6 m (20 feet) and 60-90 cm (2-3 feet) above the ground Parapet wall: up to a height of 70-75 cm (28 inches) above the ground Platform: Extending at least 1m (3 feet) in all directions with a gentle slope towards the drain. Drain: pucca drain around the well to carry off spilled water to a public drain or soakage pit. Covering: Top closed by a cement cover. Hand pump: If possible it should be equipped with a hand pump in a Sanitary manner. 2. Slow sand filter: Important points: Space: Occupies a large area Rate of filtration: 2-3 m.g.a.d The effective size of sand: 0.2-0.3 mm Preliminary treatment:  Plane sedimentation. Washing: By scraping the sand bed Operation:  Less skilled Loss of head allowed:  4 feet (1.5 m) Removal
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Spotters in "Environment and Health: Insecticides" for CFM & MPH students

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Insecticides:   These are substances that are used to kill insects.  Pesticides:   It is a general term that includes  insecticides, fungicides rodenticides, herbicides,  disinfectants, repellents, and other chemicals used for the  control of pests. Insecticides are classified into 3 groups: Contact  poisons, Stomach poisons and Fumigants.  CONTACT  POISONS: These are those insecticides that kill insects primarily by contact  e.g., pyrethrum, DDT, HCH, dieldrin.  STOMACH POISONS: These  are those insecticides which when ingested cause the death of the  insects, e.g., Paris green, sodium fluoride.  FUMIGANTS: These are  those insecticides that give off vapours that have a lethal effect on  the insects, e.g., sulphur dioxide. 1. DDT  (Dichloro-diphenyl-trichloroethane) :  It was first  synthesized in 1874, by a German chemist, Ziedler . I ts insecticidal properties were discovered by the Swiss  scientist, Paul Muller in  1939 .  Important points: PROPERTIES: It is a white  amorphous
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Spotters in "Environment and Health: Mosquito control Measures" for CFM & MPH students

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The integrated approach of mosquito control: This is an approach that avoids the excessive use of any one method (e.g insecticides) but tries to combine one or more methods with a view to obtain maximum results with minimum inputs and also to prevent environmental pollution with toxic chemicals & development of insecticide resistance. The various methods of mosquito control are as follows: 1. Anti- Larval Measures: (a) Environmental Control: Important Points: Source reduction : Mainly the elimination of mosquito breeding places by minor engineering methods such as  Filling- of cesspools & open ditches and arrangement for adequate collection, removal, and disposal of sewage & wastewater. Leveling & getting rid of water-holding containers such as discarded tins, empty pots, broken bottles, coconut shells, etc. Drainage of breeding places, and  Water management (e.g intermittent irrigation) & removal of aquatic plants or destruction by herbicides. Rendering the water u
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Spotters in "Environment and Health: Sanitation" for CFM & MPH students

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  1. Sanitation Barrier: Important points: Disease agents transmitted to a new host through various channels: 1. water/ fluids , 2. fingers , 3. flies , 4. soil , and 5. food   The disease cycle may be broken at various levels: 1. protection of water , 2. personal hygiene , 3. control of flies , 4. segregation of faeces , and 5. protection of foods The most effective step would be to segregate the faeces & arrange for proper disposal so that the disease agent cannot reach the new host, directly or indirectly. The segregation of the excreta by imposing a barrier called the " sanitation barrier " which can be provided by a 'sanitary latrine' and disposal pit. 2. Borehole latrine: Important points:   It was first introduced by the Rockefeller foundation during 1930s in campaigns of hookworm control. It consists of a circular hole of 30-40 cm (12-16 in.) in diameter. Dug vertically into the ground to a depth of 4 to 8 m (13-26 ft.), most commonly 6 m (20 ft.). Auger
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