National Forensic Doctor

Liu Jinghui played with his phone and observed Jiang Yuan from time to time.

He was a brain eater, so he naturally didn't need to lie on a microscope to study like a tech geek.

This also made Liu Jinghui find something strange. Jiang Yuan, who was originally looking at the manual and the microscope, seemed to be absent-minded at this time, just like a student who started to lose focus in the middle of class.

Liu Jinghui couldn't help but smile. Jiang Yuan in this state was quite a newcomer. If the police and criminals could choose each other, Jiang Yuan in this state would probably be chosen by many people.

In Liu Jinghui's mind, he couldn't help but reflect the scene of the giant dragon slaughtering the formation... The sharp dragon claws, grabbing and throwing, were the lives of several criminals; the gushing dragon flames, spraying and swinging, were the lives of a group of criminals; the thick dragon tail, smashing and turning, were the lives of a battalion of criminals...

"I'm going to invite Professor Su Lei and the others to come." Jiang Yuan retracted his gaze at some point, and his tone began to become serious.

Liu Jinghui often analyzes people around him. He saw that Jiang Yuan's condition was unusual at this time. Liu Jinghui couldn't help asking: "What did you see?"

Jiang Yuan couldn't say that he saw the system task. He rolled his eyes and blamed the microscope, saying: "The equipment bought by Lanyue City Bureau is a bit troublesome. I'm too lazy to look at it. Let Professor Su Lei come and study it."

"Is it so complicated? I saw that you were in other police stations, using their microscopes and so on, and you were very good at it." Liu Jinghui just said so, and then said: "Then you call. Wait for their time, what should we do?"

"Let's eat hot pot. My dad sent a lot of sliced ​​beef slices and freeze them in the refrigerator." Jiang Yuan said while taking out his mobile phone and calling Professor Su Lei.

The diatom database of the Taihe River Basin was made by Professor Su Lei's project team. Jiang Yuan was equivalent to the client of her team. In addition to the technical advantages of forensic botany, a phone call was made, and Su Lei immediately gave a positive answer.

After hanging up the phone, Jiang Yuan said to Liu Jinghui: "There is nothing else to do today. Zhang Lei's DNA has just been obtained. It will be almost tomorrow when the comparison is completed. Let's go back."

Different samples require different amounts of time to compare DNA. The most time-saving and labor-saving is blood, and when a corpse rots, the first thing to spoil is also blood.

The criminal science laboratory in Lanyue City is quite strong, and Jiang Yuan doesn't have to worry about the normal procedures.

On the contrary, Liu Jinghui always felt a little uncomfortable skipping work with Jiang Yuan in broad daylight.

That night, Su Lei landed in Lanyue City with her doctoral student Qiao Shengli.

She is also a busy person now. Since her research direction includes forensic botany and she has published two heavy papers, Su Lei has not only been attending academic conferences continuously, but also has received attention from police stations across the country because of her cooperation with Jiang Yuan, and she is invited from time to time.

For a scholar at the Agricultural Research Institute, this is a very interesting and revolutionary change in life. Su Lei had a lot of fun.

Qiao Shengli was even more excited about her expectations.

They checked into the hotel that night, and the next morning, Qiao Shengli got up two hours earlier and put on full makeup to meet Jiang Yuan.

Jiang Yuan invited them to breakfast at Yilanju as usual.

The fried dumplings with a crispy shell and thick soup were welcomed by everyone.

Qiao Shengli couldn't help eating two, and then stared at Jiang Yuan in a daze.

Even when sitting down, Jiang Yuan was half a head taller than the person next to him, which was very conspicuous.

Qiao Shengli was thinking about what to say next while watching, and at this time, she saw the door of the box opened.

"Captain Jiang, I happened to be having breakfast here, and I heard that you came over. What a coincidence." Dong Xifeng, the vice president of the film and television city, was sweating on the back of his neck.

Behind him, two sleepy beauties came out, looked at Jiang Yuan again, and shouted together: "Brother Jiang..."

Qiao Shengli felt angry for no reason and ate two more fried dumplings!

…

Su Lei and Qiao Shengli also had experience in working outside. They carried all the small equipment with them and notified the Lanyue Municipal Bureau in advance to borrow large items such as clean benches.

Lanyue University had all the equipment that the Lanyue Municipal Bureau did not have. With Dai Mingsheng's presence, it was easy to determine the time.

Su Lei, Qiao Shengli and others immediately entered into the busy work.

There were not many pieces of clothing left at that time, and most of them were washed away. However, Jiang Yuan's special case team has always had strict investigation discipline. Some of the clothing fragments left intentionally, as well as some soil from the crime scene, can be used for forensic botany analysis. In particular, the remaining wool socks, the socks are well preserved, and are stained with a large amount of plant spores, and their value is still increasing.

For the dead Zhang Lei, this pair of socks should be the most useful item he bought.

The spores required for forensic botany can be as small as nanometers, so even a small pair of socks can provide a lot of information.

However, picking out the pollen one by one and putting them on slides for identification is only the first step. Classifying and analyzing the pollen is the most difficult.

There are several levels of identifying pollen. Level 1 forensic botany can roughly identify the genus and species of most pollen, but that's all.

Placed in the class Mammalia, the genus is at the same level as the genus Cat and Canis. Take the genus Canis as an example. There are 8 species in this genus, including gray wolves, coyotes, African wolves, Ethiopian wolves, etc. From the perspective of ordinary people, these different species of wolves are most likely indistinguishable. .

The domestic dogs that ordinary people are familiar with are actually just a subspecies of the "gray wolf".

There are 39 species of this subspecies, including domestic dogs, Arabian wolves, Arctic wolves, Mexican wolves, Siberian wolves, Florida wolves, Japanese wolves, Austro-Hungarian wolves, Chinese wolves, Mongolian wolves, etc.

It can be seen from the name that if you master this step, the task of classification and identification will be much easier. Because the distribution range of some plants is limited, if you can identify the key plants, you can narrow down the range a lot at once.

Of course, ultimately, you still have to rely on pollen maps. The pollen map composed of a variety of pollen spores is similar to DNA. It can be accurate to the meter level and is basically non-replicable.

Su Lei is at about LV2 level of Forensic Botany, and Qiao Shengli is at about the full level of LV1. Therefore, Su Lei can barely do Forensic Botany, but she does it very slowly and has to constantly look up information for comparison.

Qiao Shengli is basically unable to independently carry out forensic botanical identification work. Her experience is still shallow and her taxonomy accumulation is small. She can only identify the "grey wolf" species independently. After that, she can basically identify each botanical classification. You have to check the information, and even compare it very carefully with the information. This is an unacceptable time cost for a murder case.

If Jiang Yuan handles the case with LV4 forensic botany, it can only be said to be just enough.

However, if he opens the temporary +1, he can easily identify the subspecies. Although he still needs to check the information for some unfamiliar genera and species, for the case, identification at this level has already brought Immediate change.

In the canine genus, Jiang Yuan can already tell the difference between a husky and a golden retriever.

This means that Jiang Yuan was very relaxed in the first session. Likewise, botanists of this caliber would not be able to do anything in the classification and analysis of pollen.

And this scene, in Qiao Shengli's eyes, couldn't help but feel a little unbelievable.

She waited until Jiang Yuan took a break, then quickly took a hot water bottle, went to refill Jiang Yuan's water, and then asked: "In this case, it should be difficult to distinguish the first scene from the second scene during the classification process. Which sporopollen are It’s easy to confuse which ones are contaminated at the first site and which ones are contaminated at the second site.”

"There are many ways to distinguish between the first and second sites." Jiang Yuan drank tea and said relaxedly: "The most basic method is to analyze the spores from the second site first. Eliminate the spores from the second site. Pink, the rest..."

"The rest are from the first scene!" Qiao Shengli answered enthusiastically.

Jiang Yuan smiled and said, "It may also be the pollen brought by the murderer."

The victim's body was moved here, and it may be contaminated with spores along the way. The contact between the murderer and him will inevitably lead to the exchange of spores.

"That's right, I didn't think that carefully." Qiao Shengli looked cute and girly in full makeup.

Jiang Yuan made a "gumble" sound, swallowed his saliva, and then said: "The place where the victim passed during his lifetime may also be contaminated with pollen."

"Yes, there are so many factors involved." Qiao Shengli frowned slightly.

"It sounds difficult, but in fact, if you analyze it one by one, it is just that. The places where the victim passed by during his lifetime must have been contaminated with pollen. The number of pollen per unit area is relatively small, and it should be wind. Mainly pollen plants. After the victim dies, the amount of pollen exposed to the ground increases exponentially."

Qiao Shengli listened carefully, still frowning and nodding.

For her, this level of judgment is too difficult.

Jiang Yuan smiled and said: "In this case, there is another trick."

"What can I do?"

"Wool socks." Jiang Yuan continued to increase the value of wool socks, saying: "The victim must have been wearing shoes before his death, so the part below the sock tube was less likely to come into contact with pollen before the victim died. Wool Socks are particularly prone to retaining pollen... In fact, just analyzing this pair of wool socks is enough to make a forensic botanical judgment. "