Spring used a Brush surface-analyzer in a metal-cleaning study and showed considerable differences in soil removal, depending upon surface roughness.

Carpenter's study showed that female common garter and ribbon snakes of Michigan mature at about the age of two.

Their study showed that it was possible to transfer 3 to 4 lb of oxygen / hr. / hp.

A study on the relationship happiness to various character strengths showed that “ a conscious focus on gratitude led to reductions in negative affect and increases in optimistic appraisals, positive affect, offering emotional support, sleep quality, and well-being .”

The psychologist David H. Barlow of Boston University conducted a study that showed three common characteristics of people suffering from chronic anxiety, which he characterized as " a generalized biological vulnerability ," " a generalized psychological vulnerability ," and " a specific psychological vulnerability.

) This was changed because a government study showed that many people were in effect " saving up " their units and using them at the end of the week, a phenomenon referred to as binge drinking.

( 1990 ) carried out a radial velocity ( Doppler shift of spectral lines ) study of the star in April and May 1988, which showed variability with a frequency of the order of a few microhertz, the highest peak corresponding to 4. 3 μHz ( 2. 7 days ) with an amplitude of 60 ms < sup >− 1 </ sup >, with a frequency separation of ~ 5 μHz.

The first large-scale trial evaluating the efficacy of BCG was conducted from 1956 to 1963, and involved 54, 239 school children who received BCG at the age of 14 or 15 ; this study showed an efficacy of 84 % up to five years after immunization.

The MRC study showed protection waned to 59 % after 15 years and to zero after 20 years ; however, a study looking at native Americans immunized in the 1930s found evidence of protection even 60 years after immunization, with only a slight waning in efficacy.

A recent study has showed that these nylon-3 polymers can either mimic host defense peptides or act as signals to stimulate 3T3 stem cell function.

A 2005 study by researchers at Ghent University in Belgium showed that subclinical iron deficiency ( anemia ) was a strong predictor of bacterial vaginosis in pregnant women.

A longitudinal study published in February 2006 in the American Journal of Obstetrics and Gynecology showed a link between psychosocial stress and bacterial vaginosis independent of other risk factors.

The cane toad has a high tolerance to water loss — one study showed some can withstand a 52. 6 % loss of body water, allowing them to survive outside tropical environments.

Some evidence indicates that during armoured combat the intention was to actually get around the armour rather than through it — according to a study of skeletons found in Visby, Sweden, a majority of the skeletons showed wounds on less well protected legs.

A study showed that of 100 coyotes collected in Maine, 22 had half or more wolf ancestry, and one was 89 % wolf.

A recent study showed that there is a bivalent structure present in the chromatin: methylated lysine residues at location 4 and 27 on histone 3.

A 1998 case study showed that software engineering majors who successfully completed a technical writing course created capstone experience projects that were more mindful of end user design than the projects completed by their peers.

A 1998 DNA study showed a match between the Jefferson male line and a male descendant of Sally Hemings.

Another study shows that people who experience SWS during the first half of their sleep cycle compared to subjects who did not, showed better recall of information.

A 2008 study published in the American Journal of Preventive Medicine showed that dieters who kept a daily food diary ( or diet journal ), lost twice as much weight as those who did not keep a food log, suggesting that if you write your food down, you wouldn't eat as many calories.

A second study showed that poxvirus, baculovirus and the animal herpesviruses form separate and distinct clades.

A study in 1991 showed that $ 20. 1 million came from sales related to waterfowl hunting along the Detroit River.

A study of American college students published in Nature showed that people are willing to pay to reduce inequality.

In a follow-up study, Swiss children showed a significant increase in sharing between the ages of 3 and 8.

The reaffirmation of American faith in the comprehensive high school, as expressed in the Conant study, is another indication of the liveliness of the ideal of maximizing opportunity through the equalizing of educational opportunity.

As a young man, Nobel studied with chemist Nikolai Zinin ; then, in 1850, went to Paris to further the work ; and, at 18, he went to the United States for four years to study chemistry, collaborating for a short period under inventor John Ericsson, who designed the American Civil War ironclad USS Monitor.

Lomax was the first prominent scholar to study distinctly American folk music such as that of cowboys and southern blacks.

The same year, a study by the Boston Society for Psychical Research concluded that Chaplin was " an American obsession.

The diversity of systems and phenomena available for study makes condensed matter physics the most active field of contemporary physics: one third of all American physicists identify themselves as condensed matter physicists, and The Division of Condensed Matter Physics ( DCMP ) is the largest division of the American Physical Society.

In 1941, American cavers organized themselves into the National Speleological Society ( NSS ) to advance the exploration, conservation, study, and understanding of caves in the United States.

A 40-year study of African, Asian, and South American tropical forests by the University of Leeds, shows tropical forests absorb about 18 % of all carbon dioxide added by fossil fuels.

In October 2009, the American Association of Cheerleading Coaches and Advisors ( AACCA ), a subsidiary of Varsity Brands, released a study that analyzed the data from Emergency Room visits of all high school athletes.

The American impressionist Mary Cassatt, who at one point lived in Paris to study art, and joined his Impressionist group, noted that he was “ such a teacher that he could have taught the stones to draw correctly .”

Eisenhower's stint as president of Columbia University was punctuated by his activity within the Council on Foreign Relations, a study group he led as president concerning the political and military implications of the Marshall Plan, and The American Assembly, Eisenhower's " vision of a great cultural center where business, professional and governmental leaders could meet from time to time to discuss and reach conclusions concerning problems of a social and political nature ".

Nice wrote to Joseph Grinnell in 1932, trying to get foreign literature reviewed in the Condor: " Too many American ornithologists have despised the study of the living bird ; the magazines and books that deal with the subject abound in careless statements, anthropomorphic interpretations, repetition of ancient errors, and sweeping conclusions from a pitiful array of facts.

Among his substantial publications from this period were his book on " Time Perspective in the Aboriginal American Culture " ( 1916 ), in which he laid out an approach to using historical linguistics to study the prehistory of Native American cultures.

Environmental law courses are offered as elective courses in the second and third years of JD study at many American law schools.

Introductory educational psychology is a commonly required area of study in most North American teacher education programs.

Lomax was the first prominent scholar to study distinctly American folk music such as that of cowboys and southern blacks.

An anthropometric study of 1197 North American adult Caucasian males ( mean age 35. 5 years ) found that a man's foot length was 26. 3 cm with a standard deviation of 1. 2 cm.

In economics, a study ( done by Pew Charitable Trusts, the American Enterprise Institute, the Brookings Institute, the Heritage Foundation and the Urban Institute ) challenged the notion that each generation will be better off than the one that preceded it.

The study, ' Economic Mobility: Is the American Dream Alive and Well?

* Smith, Gary Scott, Heaven in the American Imagination ( Oxford University Press ; 2011 ) 339 pages ; draws on art, music, folklore, sermons, literature, psychology, and other realms in a study of how Americans since the Puritans have imagined heaven.

Hefner donated $ 100, 000 to the University of Southern California's School of Cinematic Arts to create a course called " Censorship in Cinema ," and $ 2 million to endow a chair for the study of American film.