Accounting	2
Acridology	1
Aeronautics	1
Agriculture	162
Animal husbandry	5
Antennas and waveguides	5
Astronautics	3
Automated equipment	15
Automobiles	25
Aviation	10
Banking	4
Baseball	1
Biotechnology	1
Botany	1
Business	4
Chemical fibers	1
Chemistry	119
Cinematography	5
Coal	15
Commerce	4
Communications	142
Computer numerical control	2
Computers	2
Construction	15
Corporate governance	8
Criminal law	5
Cultural studies	6
Data processing	1
Drilling	12
Dyalysis	3
Earth sciences	86
Economics	61
Education	55
Electric machinery	4
Electric traction	3
Electricity generation	1
Electronics	253
Energy industry	31
English	1
Environment	61
Finances	34
Fish farming pisciculture	7
Fishery fishing industry	14
Food industry	36
Food service and catering	7
Footwear	2
Forestry	27
General	167
Genetics	1
Geology	1
Government, administration and public services	1
Health care	32
Helicopters	1
Hobbies and pastimes	5
Horticulture	1
Human rights activism	10
Ichthyology	1
Immigration and citizenship	2
Industry	63
Information technology	139
Insurance	1
International Monetary Fund	26
Isolation	1
Labor law	10
Laboratory equipment	4
Lasers	1
Law	39
Life sciences	42
Lighting other than cinema	3
Loading equipment	8
Marketing	2
Materials science	32
Mathematics	3
Measuring instruments	19
Mechanic engineering	69
Medical	93
Metallurgy	116
Meteorology	83
Mexican	6
Microsoft	21
Military	1
Milk production	5
Mineral products	1
Mining	2
Municipal planning	4
Name of organization	52
Natural resourses and wildlife conservation	6
Natural sciences	37
Nautical	1
Navigation	1
Nuclear and fusion power	1
Nuclear physics	22
Obsolete / dated	4
Oceanography & oceanology	1
Oil / petroleum	2
Oil and gas	1
Packaging	15
Patents	3
Pharmacy and pharmacology	2
Photography	1
Physical sciences	7
Piezoelectric crystals	1
Plastics	1
Politics	24
Power electronics	1
Power lines	1
Psychology	6
Radio	4
Radiology	1
Rail transport	1
Remote sensing	10
Research and development	3
Scientific	2
Scuba diving	1
Social science	13
Sociology	1
Soil science	3
Sound recording	1
Statistics	15
Sugar production	4
Superconductivity	5
Taxes	3
Technology	186
Telecommunications	1
Textile industry	22
Thermal Energy	9
Trade unions	1
Transformers	2
Transport	179
United Nations	55
Veterinary medicine	1
Video recording	1
Virology	2
Water resources	13
Wood processing	5
Work flow	1