High blood splatter

“Get ready!” This immortal motto of the Scout movement will come to the mind of many readers who read the paper “Dynamics of bloodstain patterns in microgravity environment: Pilot study observations on the next frontier of forensic medicine.”

Reader Sarah Rosenbaum flagged feedback on the study’s first clearly stated purpose: “Investigating the ultimate violent criminal acts that occur outside of the global environment.”

This is the most futuristic forensic science. “It’s almost here.” The most effective approach is joint criminal investigation between the United Kingdom and the United States. The researchers are from Staffordshire University and Hull University in the UK, and the University of Louisville in Kentucky and Roswell Police in Georgia in the US.

“We hypothesize that the calculated impact angles would be more accurate if gravity were removed as a force acting on the blood droplet in flight,” they write.

They performed tests, or rather flew, aboard a parabolic flight research airplane that took off and landed at Fort Lauderdale-Hollywood International Airport. (Fort Lauderdale, like many cities in Florida, is no stranger to blood splatter. We see a steady increase in the number of violent crimes According to statistics reported by the local police department’s crime analysis department, it will occur between 2020 and 2023.)

In the experiment, “a 1 cc syringe containing a blood analogue was used to inject the liquid onto a flight path approximately 20 cm long, which was intercepted by a 16.5 cm x 16.5 cm target.” [made of] Fifty pound paper adhered to foam board backing.

The study found that droplets that hit paper at a 90-degree angle behaved as predicted by the traditional forensic blood droplet equation. But while this is a blood-stirring challenge for forensic scientists and true crime enthusiasts alike, someone needs to come up with a better equation for predicting what will happen from the other angle.

Thinking: Inside the box

Seeing sometimes leads to believing. Feeling, hearing, and reasoning are equally powerful when combined.

Shorey Croom, Hanbei Chow, and Chaz Firestone of Johns Hopkins University in Baltimore, Maryland, explain this in the magazine. PNAS How did they try to answer the question “?” “Can you tell what another person is trying to learn just by observing their movements?”

They filmed a volunteer shaking an opaque box and attempting to measure i) the number of objects hidden inside, or ii) the shape of the objects inside. He then asked others to watch the video and tried to determine “who is shaking because of the numbers and who is shaking because of the shapes.” Most observers were pretty good at recognizing who was shaking and why.

Back in 2017, Milte Plesier of Delft University in the Netherlands and Jeroen Smeets of Vrije Universiteit Amsterdam spoke to attendees of the IEEE World Haptics Conference in Fürstenfeldbruck, Germany, about a project they called “How many objects are in this box?”

Their method was simple. “We investigated how accurately participants could determine the number of wooden balls inside a box by shaking it.” They found that while they were able to perform the task accurately, they systematically underestimated the number of more spheres. The larger numbers they tested were 4 and 5. The situation with larger quantities remains theoretically unknown.

stick to fruit

Many scientists will not be able to determine whether the metal sticks to the fruit.

Generally speaking, if properly persuaded, they will. News about this can be found at “Reversibly attaching metals and graphite to hydrogels and tissues” by Wenhao Xu, Faraz Burni, and Srinivasa Raghavan of the University of Maryland.

writing in diary ACS Central Science “We have discovered that hard conductors (such as metals and graphite) can be bonded to soft aqueous materials (such as hydrogels, fruit, and animal tissue) without the use of adhesives.” The adhesion is caused by a low direct current electric field… [This] It can also be achieved underwater, where normal adhesives cannot be used.

“The experiment is very simple,” the study says, anticipating that many people would be surprised by such a simple, hitherto essentially unknown effect.

Accidental genital glow

Faraz Alam sent us the results of his research with colleagues at Imperial College London, published in the journal 2013. PLoS One “This is the paper on which I accidentally made my genitals glow in the dark.” The title is “Non-invasive monitoring of Streptococcus pyogenes vaccine efficacy using intravital optical imaging”. Those reproductive organs belonged to mice.

This spurred feedback that reminded me of a paper on humans published in 1950 by P. A. MacDonald and M. Sidney Margolese. Obstetrics and gynecology questionnaire. They called it “Luminous phenomenon of female external genitalia”.

These are both examples of how scientists perceive the wonders of biology.

Mark Abrahams hosted the Ig Nobel Prize ceremony and co-founded the magazine Annals of Improbable Research. Previously, he was working on unusual uses of computers.his website is impossible.com.

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