Inside the testing room.

When Gu Chen finished extracting the dirt from Wang Jinshan's ten fingers, He Wenjun stepped forward and asked, "Do you know what this is?"

"It's hard to say yet. After Gu Chen sealed the small transparent forensic bag, he marked the number on the label paper, and then said: "Further testing is needed, because these dirts are in powder form, at least I need to test before I can know." ”

Looking at Gu Chen's suspicious look, Liu Zhiqiang on the side asked, "Could the dirt in the gap between the nails be left behind by Wang Jinshan when he scratched it?"

"Perhaps. Gu Chen said very simply, but he sighed.

This caught He Wenjun's attention.

He Wenjun asked Gu Chen, "What are you feeling? Is it because the deceased knew you?"

Gu Chen shook his head: "Not really." ”

"Then why are you?" He Wenjun heard this, and felt that there was something in Gu Chen's words.

Gu Chen didn't answer immediately, but put the bag on the parallel testing table, and then turned around and said to He Wenjun:

"You speculated that the deceased Wang Jinshan died of drunken swimming, but I don't think so, because according to the time of death, He Wenjun died around the early hours of last night. ”

"But you have to know that the last time I saw Wang Jinshan was dinner time. ”

"He was drunk at the time, but after we gave him milk, he started to get better. ”

Looking around, Gu Chen said again: "When he left, his consciousness had already begun to gradually awaken. ”

"But in such a state, how could he have drowned in the pool drunk around the wee hours of the morning?"

"Unless there is a possibility, that is, he drinks again at home, so I want to ask, have you found any traces of Wang Jinshan's drinking in his house?"

"This ......"

Being asked by Gu Chen suddenly, He Wenjun was stunned for a moment, shook his head and said, "I didn't find out about this, just because we found out that Wang Jinshan had drunk last night, so we just made a rough guess." ”

"That's uncertainty. Gu Chen affirmed.

Liu Zhiqiang, who was on the side, frowned, turned his head and asked Gu Chen: "Officer Gu, how do you know that the time of death of the deceased Wang Jinshan was around the early hours of last night?

"Don't decide. Before Liu Zhiqiang could finish speaking, instructor Zhang Hui stood up straight, and also took a deep breath and said, "Gu Chen is right, the time of death was indeed around the early hours of last night. ”

"Really...... Really?" Liu Zhiqiang was a little incredulous, turned his head to look at Gu Chen, and said unknowingly: "But...... Gu Chen had just come in not long ago, he was just making a simple observation of the corpse, how could he determine the time so quickly?"

Glancing at Zhang Hui, Liu Zhiqiang said again: "Even you, Teacher Zhang, haven't completed the comprehensive test yet, is this ...... How the hell is this ......?"

"I don't know, but he's right. Zhang Hui shook his head and smiled, turned his head to look at Gu Chen and asked, "Gu Chen, how did you know the time of the deceased's death? ”

"And you just scraped the dirt from the fingernails of the deceased Wang Jinshan, and you can determine the time of death?"

"Of course not. Gu Chen shook his head directly and explained: "In fact, to identify the cause of death of the deceased, I also judge it based on previous experience. ”

"Experience?" He Wenjun was a little surprised, after all, the autopsy work has always been done by the forensic team.

Gu Chen is not a non-doctor, but he is talking about experience here?

He Wenjun felt a little incredible.

And Gu Chen pressed the corpse with his fingers to show everyone: "In fact, to judge the time of death, it can generally be determined by three directions, the first is to look at the stiffness of the corpse. ”

"That's right. Instructor Zhang Hui agreed with Gu Chen's opinion, and also nodded slightly: "This is a method that our forensic doctors usually use to detect corpses. ”

Glancing at Gu Chen, Zhang Hui asked again, "Then what is your judgment standard?"

"It's simple. Gu Chen poked the corpse with one finger and said, "Under normal circumstances, the corpse will harden between 30 minutes and 2 hours after death, it will be completely rigid after 9 hours to 12 hours, softened after 30 hours, but after 70 hours, it will return to its original state." ”

Seeing Zhang Hui nodding slightly, Gu Chen said again: "But it is worth noting that if it is in soil or water, or in the case of low temperature and dryness, there will be a delay, and it will be accelerated under high temperature and humid conditions." ”

"I also made a judgment based on these foundations, combined with some previous experience. ”

"Hmm. Zhang Hui was very satisfied with Gu Chen's answer.

Previously, he was also using these data to compare the corpses, and deduced that the time of Wang Jinshan's death may have been around early in the morning.

But Gu Chen could also judge it at a very fast speed, which made Zhang Hui look at Gu Chen differently.

Also looking at Gu Chen differently are He Wenjun and Zhang Zhiqiang.

The two and Gu Chen are peers, but for autopsies, most of them rely on the forensic team.

But being surpassed by the young peer in front of them, everyone felt a little embarrassed.

Liu Zhiqiang couldn't help but joke: "What you said is quite reasonable, so in addition to this, what other basis can you use to judge the time of death?"

"It's too much. Gu Chen raised his finger and explained to everyone: "There is also a judgment based on the temperature of the corpse. ”

"In general, within 10 hours of death, the temperature of the corpse drops by 1 degree per hour, and more than 10 hours after death, the temperature of the corpse drops by 0.5 degrees per hour. ”

Hearing Gu Chen's words, He Wenjun and Liu Zhiqiang looked at Zhang Hui together.

Zhang Hui also nodded silently, agreeing with Gu Chen's statement, and still calculating the corpse according to the data provided by Gu Chen.

"So...... You just took the tool, and in addition to extracting the dirt from the cracks in the nails of the corpse, you also carried out a temperature test?"

"That's right. Gu Chen nodded slightly and admitted: "I did test the temperature of the corpse just now, otherwise it would be difficult to judge the condition of the corpse." ”

"Then what about another direction?" Zhang Hui realized at this moment that Gu Chen seemed to be far from being as simple as he imagined.

It seems that this guy is quite familiar with the business of forensic work.

Gu Chen blurted out directly: "There is also a judgment based on the purple-red patches that appear on the skin under the corpse after the person dies, that is, corpse spots. ”

"Because corpse spots usually appear 2 to 4 hours after death, they develop to their maximum height after 12 to 14 hours, and they are fixed between 24 and 36 hours and do not metastasize. ”

"However, the occurrence and development of the general cadaveric phenomenon is greatly affected by internal and external factors, so it should be objectively analyzed based on all conditions. ”

"That's great. Zhang Hui pouted and smiled, and couldn't help but say: "Gu Chen, I didn't expect that you could comprehensively judge the time of death of the deceased just by passing these conditions, which is very rare, and it can be seen that you usually put in a lot of effort." ”

"Of course. Seeing that instructor Zhang Hui began to praise Gu Chen, Lu Weiwei was overjoyed and said: "Instructor Zhang, I have long said that my junior brother Gu knows more about this aspect of business, but you still don't believe it." ”

"No, no. Zhang Hui interrupted Lu Weiwei and said, "It's not that I don't believe it, it's just that Gu Chen is too young, and it stands to reason that he is definitely not familiar with the autopsy business." ”

"At least in my opinion, young forensic doctors have some problems with testing. ”

"There may be some peers who can accurately judge the cause of death of the deceased like Gu Chen, but it is very rare to be able to make a preliminary judgment as quickly as Gu Chen, but it is accurate, at least I haven't met it yet. ”

"It's pretty impressive. Liu Zhiqiang had to admire, even Zhang Hui was full of praise for Gu Chen, which shows that Gu Chen's business is solid, and it is indeed extraordinary.

Such multi-faceted and infrequent occurrence is rare in the police force.

He Wenjun also smiled and said, "Gu Chen, it turns out that you are so familiar with these forensic work, no wonder you rushed to come to Teacher Zhang to help, I really underestimated you just now." ”

"Actually, I didn't want to rush here to help. Before He Wenjun could finish speaking, Gu Chen directly interjected: "Mainly because the deceased had contact with me, I still know some of his situation." ”

"Coming here may be able to provide you with some ideas for handling cases, so ...... That's what I'm here for. ”

Hearing Gu Chen's words, He Wenjun and Liu Zhiqiang looked at each other, and the two couldn't help but give a thumbs up.

"It seems that you have come to the right place, welcome to join the case handling team, I hope you can provide us with help in the testing room. ”

He Wenjun still had doubts before, wondering why Gu Chen appeared here?

However, the current He Wenjun no longer has any opinions on Gu Chen.

Gu Chen also nodded slightly, expressing his gratitude.

At this time, Zhang Hui took the nail dirt extracted by Gu Chen and prepared to enter the inspection on the testing platform.

Officer Wang said more: "If Wang Jinshan drowns in his own pool, then unless the dirt is on his body, there will be some problems." ”

"It's not a problem, it's a big problem. Gu Chen directly corrected Officer Wang: "In my opinion, these dirt are more like some mud, sand and plant debris. ”

"What do you mean......"

Hearing Gu Chen's words, He Wenjun's brows furrowed slightly.

"That's right. Gu Chen did not shy away from it, and said bluntly: "When people are drowning, they will do everything they can to grab anything around them and try to survive. ”

"Therefore, drowning people often clutch dirt, small stones, plants, etc., and they can often be found in their fingernails, and these things can also be used to determine the exact location. ”

"If a body is found in a swimming pool, then if a forensic autopsy finds debris in the deceased's lungs or fingernails that are not present in the pool, it is possible that the deceased drowned elsewhere and was later abandoned in the pool, pretending to be an accidental drowning. ”

"What Senior Brother Gu means...... The swimming pool in the home of the deceased Wang Jinshan may not be the first scene?"

"Yes, that's what it means. Gu Chen nodded slightly, and said lightly: "If you can compare the specific origin of the substances contained in the debris, such as pollen, feather seeds, etc., it may be able to indicate that the deceased drowned there." ”

"You have a point. He Wenjun agreed with Gu Chen's opinion.

But as a peer, He Wenjun couldn't help but say a few more words, and by the way, educate Liu Zhiqiang beside him:

"Actually, when performing an autopsy, can you tell where the drowning person drowned, let's say, in a bathtub or in a river?"

"If you can, to what extent you can be clear, you need the deceased to conduct a detailed examination, and Gu Chen just scraped the dirt between the fingers of the deceased Wang Jinshan is a good method. ”

"Yes. Gu Chen nodded slightly, and also took off the contaminated gloves and threw them into the trash can beside him, and then said:

"When a person is drowning, he sucks water and the substances contained in it into his mouth, nose, throat and lungs. ”

This includes leaves, insects, seeds, pollen and other debris. ”

"If you drown in a river or other natural water, then the animal and plant material found in the lungs of the deceased may be found in a particular area. ”

"It's like finding pine pollen or pine needles in the lungs, which means that the victim drowned in a place where pine trees grew near the water. ”

"Even if it is replaced by other trees and other plants, it is also valid. ”

After a pause, Gu Chen said again: "And insects also have a specific distribution area, so finding insects in the lungs can also hint at a specific place." ”

"All tests are the same, and that's the right standard. ”

"But ......" Hearing this, Liu Zhiqiang hesitated a little and asked Gu Chen: "But the water in the pool is usually quite clean, so wouldn't you find other clues?"

"It's okay too. Gu Chen seamlessly connected and said directly: "The water in the swimming pool is usually quite clean, but most of it contains chlorine, but this can be detected." ”

"Natural waters are completely chlorine-free, and it is very likely that humans have carried out this test as early as the 60s of the last century, but it is not common. ”

Looking at Liu Zhiqiang's thoughtful appearance, Gu Chen said again: "So as for the water in the bathtub, it should be very clean and does not contain chlorine, but it may contain some soap or grease, which can also be detected." ”

"So the substances contained in the inhaled water can often be used to help determine the location of drowning. ”

"I understand, no wonder Mr. Zhang asked us to take pool water samples, it turns out that this is the truth. ”

"Haha. Listening to Gu Chen's explanation to the two people, Zhang Hui, who was sitting on the testing platform, couldn't help but smile, and also reminded and said:

"You may have almost forgotten about me, of what I was good at. ”

"How can it?" He Wenjun glanced at Zhang Hui, and also took the initiative to show goodwill: "You are an expert in diatom testing, why don't you cooperate?"

Zhang Hui on the testing table smiled, and also said teasingly: "You really can't rely on me." ”

"Since the German scientist Revenstorf used a microscope to detect diatoms from lung drowned fluid in 1904, forensic scientists at home and abroad have conducted in-depth research on diatom testing methods. ”

"But in fact, you don't know, my country began to carry out diatom inspection and research in the 30s of the last century. ”

"In the 60s of the last century, six provinces and regions in central and southern China conducted joint research on how to improve the detection rate of diatoms, and my father was one of the research diatom detection teams. ”

"So that's the case?" Lu Weiwei was also surprised, and couldn't help complaining: "It turns out that Instructor Zhang is from a family of forensic doctors? ”

"Haha, it's okay, it's mainly influenced by my father. Zhang Hui didn't care about this, just like showing off his knowledge in front of everyone.

It doesn't matter, Gu Chen couldn't help it, and answered directly: "That's right, I have also read the relevant documents, but I didn't expect that there was Instructor Zhang's father in the diatom testing team in the early years." ”

"It was a very distant time, so let's not mention it now. Instructor Zhang Hui tested one sample and then took out another.

Gu Chen said lightly: "I remember that in 1998, the Canadian forensic pathologist, Michel Berlangen, in his book "Forensic Diatomology and Drowning", for the first time made a comprehensive discussion on the scientific and forensic principles of diatom testing. ”

"I also read that book a few months ago, in which the author proposed the concept of forensic diatomology, which includes the principle, effectiveness, and practicability of diatom testing to diagnose drowning, as well as the methods and procedures of diatom testing. ”

"Because diatoms are gradually recognized as the most reliable marker for the diagnosis of drowning, diatom testing is also generally regarded as a more reliable means of diagnosing drowning, especially for the diagnosis of the cause of death of decomposing corpses in water, which is regarded as the most effective method and can be called the 'gold standard'. ”

"This is a great improvement compared with the previous backward detection methods and crude experiments. ”

After a pause, looking at Liu Zhiqiang and He Wenjun, Gu Chen said again: "When a person is drowning, the diatoms in the drowning fluid will break through the alveoli of the lungs, thus entering the blood of the human body for circulation, and distributing to the brain and various internal organs with the blood flow of the drowning deceased. ”

Therefore, today's diatom testing technology is mainly by identifying the presence of diatoms in the body of the deceased. ”

"If the analysis of the diatom test technology in the internal organs of the deceased's body is positive, and the type of diatom is consistent with the water sample from the field, the deceased can be determined to have died by drowning. ”

And now Wang Jinshan's body needs to verify this. ”

"However, there are many types of diatoms and they have different forms, and the composition of diatoms in each water source is different. Instructor Zhang Hui glanced sideways at Gu Chen, which was also a test on the spot.

Gu Chen blurted out and said seamlessly: "That's right, there are many types of diatoms, but diatoms are single-celled organisms that are widely distributed in water, and the cell wall is composed of a large amount of silica, which is extremely stable and hard. ”

"Therefore, as long as the qualitative and quantitative analysis of diatoms in the main organs of the body in the water is detected, not only can the cause of death be more directly judged, but also the possible place of drowning. ”

"Bang!"

As soon as Gu Chen's words fell, instructor Zhang Hui's arm touched the tray where the utensils were stored, and it made a banging sound for a while.

"Instructor Zhang, are you alright?" Gu Chen's gaze was attracted.

Zhang Hui waved his hand: "It's okay, I just found some abnormalities, so I accidentally touched the tray." ”

......