Before the mid-20th century, bed bugs were very common. According to a report by the UK Ministry of Health, in 1933, all the houses in many areas had some degree of bed bug infestation. The increase in bed bug populations in the early 20th century has been attributed to the advent of electric heating, which allowed bed bugs to thrive year-round instead of only in warm weather. Bed bugs were a serious problem at US military bases during World War II. Initially, the problem was solved by fumigation, using Zyklon Discoids that released hydrogen cyanide gas, a rather dangerous procedure.
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Oldowan chopper H. habilis is associated with the Early Stone Age Oldowan stone tool industry. Individuals likely used these tools primarily to butcher and skin animals and crush bones, but also sometimes to saw and scrape wood and cut soft plants. Knappers appear to have carefully selected lithic cores and knew that certain rocks would break in a specific way when struck hard enough and on the right spot, and they produced several different types, including choppers, polyhedrons, and discoids. Nonetheless, specific shapes were likely not thought of in advance, and probably stem from a lack of standardisation in producing such tools as well as the types of raw materials at the knappers' disposal.
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Insect and rodent control instruction included: general discussion of diseases transmitted to man, insect vectors, methods of extermination, and demonstration of use of all types of equipment. Training aids included: Films: TF 1-3343 "Malaria Discipline"; and TF 8-1288 " Louse-borne diseases". Blackboard, Repellents (612, Indalone, Dimethyphthalate, Combination 6-2-2, Bednet in place, head nets, mosquito protective gloves, plastic screen, 16x18 mesh screen, aerosol bomb, methyl bromide, fumigation bag, fly spray, fly trap, sodium arsenite, DDT dust plus talc, DDT dust plus pyrophyllite, DDT 5% kerosene spray, paris green undiluted, paris green 5% with flour, fuel oil, borax, paradichlchlorobenzene rotary duster, knapsack sprayer, hand sprayer, delousing duster, motor driven duster, motor-driven sprayer, mosquito larva, pupa and adult specimens, fly egg, larva, pupa and adult specimens, flea larva, pupa and adult specimens, Phlebotomus adult specimens, louse egg, nymph and adult specimens, bedbug egg, nymph and adult specimens, cockroach egg, nymph and adult specimens, rat poisons (barium carbonate, zinc phosphide, calcium cyanide, cyanide discoids), rat traps, bait box.Army Hist. Vol.
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