Attending ex-girlfriend's wedding, arresting the groom's officer on the spot

Chapter 231

Of course, Lu Chuan only briefly explained.

The specific operation is much more detailed.

Those who can judge the time of death by judging the length of the maggot at a glance are mostly written in the script.

In fact, in forensic entomology, judging the time of death of a dead body through the growth cycle of dead body parasites requires many experiments to assist.

Wang Changjiang was a little confused after hearing Lu Chuan's explanation.

With his knowledge reserve as a professional forensic doctor, of course he can understand what Lu Chuan is saying.

But it was because he could understand that he was confused.

Isn't Lu Chuan a criminal police officer?
When did you even know about forensic entomology, a relatively rare specialty even in forensic medicine?
He knows the identification and analysis of bones, and now he seems to have some understanding of forensic entomology.

What did this guy study when he was in college?
Behind the gas mask, Shen Yan's expression was very calm.

Lu Chuan once told her that he had some knowledge of forensic entomology.

Although Liu Guodong didn't know that Lu Chuan also had some research on forensic entomology.

However, in terms of current survey, fingerprint identification analysis and bone identification analysis, etc., Lu Chuan has shown enough.

Now that there is one more item, it seems that nothing is impossible.

cough cough.

Liu Guodong coughed lightly: "That's it, I'll go back to do the experiment first, Yang Sen and Lao Bai haven't come out with the identification test for sharp knives, I'll go over and keep an eye on it."

"Xiao Lu, there is nothing serious about us, you can help Wang Forensic to identify the time of death of the corpse."

Liu Guodong took his clothes and left.

"What needs to be done next?"

As the chief forensic surgeon in charge of the autopsy, Shen Yan first sought Lu Chuan's opinion before performing the operation herself.

"I need to collect a sufficient amount of larvae, as well as some skin and internal organ fragments on the surface of the corpse."

"The best is the liver and the eyelids. If you can still extract it, it's best to get some."

Any parasitic eggs on the corpse, the vast majority are corpse flies.

The larvae of these corpse flies, just after hatching, have no teeth and no other means of attack.

So corpse flies will choose to lay eggs in the softest place.

On the surface of the corpse, the places where parasite eggs are first infested are the eyelids, nasal mucosa, oral mucosa and other parts.

Inside the corpse, the liver is the most tender, and it was also the first to be parasitized and then corrupted.

Shen Yan nodded. Lu Chuan was obviously not good at these specific operations, and she, a professional forensic doctor, was needed to do it.

The two chatted while working.

"I learned when I was in college that corpse fly eggs start to hatch after two or three days of parasitism, right?"

Although Shen Yan didn't do much research on forensic entomology, she had a basic knowledge reserve, not only there, but also sufficient.

Lu Chuan nodded in affirmation: "In most cases, this is the case, but the most important thing is to look at the outside temperature and humidity."

"The hatching of corpse fly eggs will only start at a temperature above 15 degrees Celsius, and the highest temperature for hatching cannot exceed 40 degrees Celsius."

"If the weather is colder, the incubation period can be delayed by up to a month or so."

"And if the outside temperature is around 35 degrees Celsius, this period will be shortened to one day, and even if the humidity is also relatively suitable, the incubation time can be shortened to about twelve hours at the shortest."

Lu Chuan put more than a dozen white and fat larvae of different sizes into the bottle, and lifted it up to have a look. All of them were extremely fat, wriggling crazily at the bottom of the bottle.

Apparently, judging by the size of the larvae, the hatching times of the eggs were not synchronized.

Shen Yan nodded, she couldn't remember these things clearly, maybe she had learned them but forgot, or maybe she hadn't learned them at all.

"I remember the book said that the eclosion cycle of a general corpse fly is about a week?"

"Well," Lu Chuan continued to put the larva that Shen Yan stripped from the corpse into a bottle: "But it is not possible to determine the death time of the corpse based on this."

Because what Lu Chuan needs to do now is to find out the largest and smallest among them, and judge their intergenerational relationship.

"The largest larvae on the corpse are not necessarily the offspring of the first batch of flies that laid eggs."

"It could very well be the second generation, maybe even the third generation."

If it is confirmed that it is the first generation, then the time for the corpse to decompose should be about a week.

And this also depends on the external environment where the corpse is located, but there is a high probability that it will not exceed two weeks.

However, the weather in Haizhou City in April has been getting warmer, but it is not very hot.

At least it hasn't reached the optimum incubation temperature for corpse fly eggs.

In this environment, the corpse will not decay quickly.

But combined with the degree of corruption of the corpse, it doesn't seem like it can become like this in a week or two.

Therefore, the corpse fly eggs may not be the first generation, but may be the second generation or even the third generation.

"The possibility of the fourth generation is very small. If the corpse fly has developed to the fourth generation, then the egg hatching time is at least one month or more."

Lu Chuan picked up a larva that was very small, only about three millimeters in size: "The weather in Haizhou City in three months is relatively cold, the decay of the corpse will not be so serious, and the breeding corpse flies will not be passed on from generation to generation so quickly."

The two were chatting, and Wang Changjiang listened quietly from the side without interjecting. He should be more interested in the content of the chat between the two.

However, as the most experienced forensic doctor in Haizhou City, I always feel a little embarrassed to ask a newly recruited criminal policeman for advice on forensic medicine, or to learn secretly.

Therefore, Wang Changjiang did not speak at all. Anyway, his task today is to record.

Shen Yan was born in a major and has worked for more than two years, so she has rich work experience and theoretical knowledge.

Dissecting a dead body is easy.

"Actually, not all maggot larvae are harmful. I read a document last year, which said that the use of fruit fly larvae to suck carrion can accelerate the rapid healing of rotten wounds."

The selection of larvae on the surface of the corpse was almost over, and Shen Yan was about to start the dissection with the knife.

"There is such a treatment method, but it is used more clinically in foreign countries, but in China, um, it is still relatively seldom used."

"The main reason is the lack of talents in this area."

Breeding fruit fly larvae is not a particularly complicated matter.

The key is how to carry out sterile culture.

Otherwise, use the fruit fly larvae bred from random carrion to treat the rotten wound. It is estimated that the old wound will not heal before a new infection will come.

But in a sterile environment, the spoilage will stop, and the fruit fly larvae will naturally not be able to hatch and grow.

This seems to be a fundamentally paradoxical subject.

However, Lu Chuan knew that it was possible to cultivate in a sterile environment, and he had knowledge of this in the identification and analysis of parasite eggs in intermediate cadavers.

(End of this chapter)