novice forensic medicine

Chapter 14 System Warning!

How would you describe the smell of corpses?
This smell is similar to stinky salted fish + rotten eggs + rotten meat, the comprehensive smell of being thrown into the dry toilet for two days to ferment, as long as you smell it once, you will never forget it.

Xu Dayuan and the people from the Tieshan Police Station all looked at Zhou Ning. Even if it was disgusting at the moment, Zhou Ning couldn't be cowardly. After all, Xu Dayuan scolded Cheng Li's mother so hard just now, he couldn't embarrass Xu Dayuan no matter what.

Zhou Ning didn't speak, just nodded to Xu Dayuan, then put down the big bag behind him, squatted on the ground to take out the contents, Zhao Xinli put down the survey box, and rubbed his nose.

"What's the smell?"

"Corpse smell."

Zhao Xinli was startled, and swallowed back the second half of the sentence he was about to say.

"Well, I'll wait for you here."

Zhou Ning couldn't say anything else. With colleagues watching, he wouldn't complain now, after all, he was the forensic doctor.

Find the isolation suit and gas mask and arm yourself.

Walking quickly to the door, a wooden door was tightly closed. With a slight push, a lock with a key inserted in the door shook, making a crisp sound.

The room was locked from the inside, looking back at Zhao Xinli.

"Help me take fingerprints on the door, and then pry the glass open without destroying the lock. Is this okay?"

Zhao Xinli nodded, put on gloves, took a brush and black powder for collecting fingerprints, and evenly brushed the black powder on the door, then scanned and found seven incomplete fingerprints.

After taking fingerprints and throwing the things in the evidence bag of the investigation box, I carefully peeled off the putty on the edge of the glass, cleaned off the nails, pasted it with tape and pulled it, and the glass fell down.

Stretch in through the glass gap, twist the key of the copper-colored three-ring lock, throw it into the evidence bag, push it lightly, and the door opens immediately.

At this time, Zhou Ning had finished dressing, including three layers of gloves, goggles, gas mask, and isolation suit. After all was armed, he picked up the investigation box and walked to the front of the main house.

Closed room, this is Conan's favorite.

Zhou Ning took a deep breath and shook off his messy thoughts.

A male corpse with a white lower body came into Zhou Ning's sight just like this, with a knife stuck in the back of his heart, pools of blood, blood drops, and traces of blood all over the ground, and flies on his body rose and fell. Fell, some milky white maggots [1] wriggled on his body.

The hairs on Zhou Ning's body stood on end, and the nausea made him feel even more hypoxic.

However, you can't be cowardly at this time.

Stepping in, Xu Dayuan and the others had already gathered in front of the door, so many eyes were fixed on Zhou Ning's movements, the old policeman who was chatting with Xu Dayuan raised his chin at Xu Dayuan.

"It seems to be a professional to be able to prepare all these things before coming here. When did you pick up the treasure?"

Xu Dayuan looked indifferent, put on a mask, and folded his arms.

"Professional, Xiao Zhou is a forensic doctor with a professional background. It is his credit that he was able to catch the suspect within 9.27 hours of the last September 24 case."

Surprised on the old policeman's face, the two continued to chat in a low voice.

Such compliments did not bring much excitement to Zhou Ning, but added a little more pressure.

Finding a clean place and putting down the survey box, Zhou Ning began to take pictures of various parts and measure the height and size of the deceased.

The left arm of the deceased was stretched out towards the door, and the right hand was curled up at the side of the head. The upper body was wearing a white half-sleeved T-shirt, and the lower body was not wearing anything. Two sneakers were scattered not far from the body. The heels of the shoes were crushed, and they were close to the door of the bedroom. The location, with clothes scattered on the floor, next to another pool of blood.

The face of the deceased was tilted to the right, the mouth was open, the tongue protruded, the eyeballs protruded, the entire face and facial features were swollen, and there was a cut on the neck, where some maggots had gathered, and part of the skin had been eaten by the maggots.

Zhou Ning's eyes ignored those maggots and flies. The state of the deceased, as if it had been scanned, had already appeared on the transparent screen in front of him.

At the same time, Zhou Ning heard a familiar sound.

Di, the system releases the task, please bind the person to choose the difficulty of the task, A. primary task; B. intermediate task; C. advanced task.

Zhou Ning is stupid, are you playing like this now?

Of the three difficulty levels, it is obviously the highest and the most difficult to complete. Of course, the rewards are also increased accordingly, but he still has self-knowledge.

It is not a little difficult to find evidence for the high-rotten corpse, but thinking of the corresponding reward, Zhou Ning is a little itchy, why don't you take a middle-level task and choose a high-level task?
I was still thinking in my head, and there was a beep in my ear, and the content on the screen had changed.

The binding person selects the intermediate task, and the task is released now.

Intermediate task content:

1. According to the evidence at the scene, conduct a preliminary analysis, and give the cause of death of the two deceased, within a time limit of 60 minutes.

2. To find the murderer and all the evidence, the time limit is 72 hours.

mission rewards:

If one of the intermediate tasks is completed alone, and the other is not completed, there will be no rewards and penalties, and the overtime meter will be invalidly submitted; if both tasks are completed within the specified time, corresponding rewards will be drawn according to the quality of completion and the remaining time.

Zhou Ning was completely stunned. Ten thousand crows flew over his head. How could this be an intermediate task?
I thank you, this is not to let me do a job for a police force alone, you can kill me.

System warning!

If the binding person abandons the task, all the rewards obtained from the system before will be withdrawn. Please confirm with the binding person, whether to give up the intermediate task?
Zhou Ning was scared.

Wrong teeth, take two deep breaths, accept the task!

Drip, the countdown begins!
With a sound, two countdown signs appeared above the big screen, one was 00:59 and the other was 71:59.

This.
Why is this still overlapping timing, is it calculated like this for an hour?
With a sigh, Zhou Ning stood up and waved to Zhao Xinli outside the door. If this is not possible, he needs to find a helper, and he will investigate by himself, and it will take more than an hour to finish.

Zhao Xinli covered his mask, put on his shoe covers, carefully avoided the blood on the ground step by step, and approached him, looking at Zhou Ning angrily.

"What's the matter, forensic doctor Xiao Zhou?"

Zhou Ning didn't talk nonsense, stuffed the camera into his arms, and threw him a mask.

"Wear two layers of the mask, which can block a little smell, and then follow my actions. I put down the sign and let you take pictures. You can take pictures. I can't finish it until noon alone. We still have to survey the scene as soon as possible. After that Take the body away."

Zhao Xinli wanted to evade, but Xu Dayuan coughed behind him, Zhao Xinli shivered, and honestly took the camera and mask like a quail, and armed himself.

"Come on, I will follow your command."

Xu Dayuan dragged the old policeman away at this time, Zhou Ning only heard part of Xu Dayuan's words.

"Let's go, let's investigate the surrounding area. The people from the village committee will call, and then call that stupid neighbor to ask. It's best to check. Is there anyone around who has a surveillance camera at home? Pick someone with a car to check. .”

Holding a stack of signboards with numbers, Zhou Ning placed the blood pools, blood drops, wiped bloodstains on the ground [2], and the surrounding areas of bloody footprints in order. Of course, the clothes and shoes of the male deceased were also placed.

Then he waved his hand, and Zhao Xinli went over to take a picture.

Zhou Ning bent down and rummaged through his pockets for his clothes and shoes. There was only a shopping receipt from Liqun in it, which he put into the evidence bags.

He picked up a few pupae with tweezers. The pupae were big and small. The color was light brown and the shell was not very hard. Zhou Ning raised his eyes and observed that the flies flying on the corpse included common housefly and mung bean fly. It's called Lucila sericata.

Looking at the wriggling maggots, Zhou Ning endured the nausea, picked up a relatively fat and strong one, and measured it with a ruler. The length was 13mm. He found smaller ones and measured a few. The lengths were 10mm, 11mm, and 12mm respectively. mm.

In his mind, he quickly recalled the part about the insects and the time of death during the site survey.

Maggots appeared in 10-20 hours after the death of the deceased, and flies grew at a rate of 2-3 mm per day. As for the appearance of fly pupae, they generally appeared in 5-7 days.

Zhou Ning squatted and moved two steps. The face of the deceased male was severely deformed. He stretched out his hand and wanted to push the head of the deceased so that he could see the complete appearance of the face, but when he just touched the forehead, the softness The touch that seemed to be about to melt made him give up this action.

However, with such a movement, the flies on the dead man's neck slammed and all flew up. At the place where the hair behind the dead man's ear meets the chin, there was a finger-sized mole with a few hairs on it.

Zhou Ning was overjoyed, and looked up to search for Zhao Xinli.

"Hurry up and take a picture!"

PS:

【1】Flies and maggots: In forensic entomology, the morphology of flies at various stages can be used to infer the time of death of the deceased, so maggots at the scene are also very important. (although it's disgusting)
The eggs develop into larvae after one day, and then develop into first-instar gnawing at the corpse one day later, then become second-instar after eating frantically for one day, and become third-instar larvae after four to six days, and pupate five days after pupation. shell.

According to the test, when the indoor temperature is 22 degrees Celsius, it takes 19 days for the eggs to develop into adults, and 25 days if the temperature is above 12 degrees Celsius.Death time = fly egg laying time + fly egg hatching time + maggot growth time.

The length of the maggot when it breaks the egg is basically about 0.175 cm.Under the same temperature and sufficient food, when the temperature is higher than 25 degrees Celsius, the coefficient of variation between the growth time of maggots and the length of maggots is about 85 hours per centimeter.

【2】Smear-like bloodstains: refers to the bloodstains formed by the blood-stained object directly contacting the carrier by smearing, rubbing, touching, rubbing, etc. and left on the carrier.

For example, when blood-stained hair is wiped, it will often form strand-like blood stains, and blood-stained fingers will often form flakes (when rubbing), lumps (when touching), dots (when grasping) and long strips (when dragging) ) of blood.

The bloodstains formed by writing or drawing with blood on hands or other objects still belong to the category of wiping bloodstains, so we regard them as a special kind of wiping bloodstains.

　PS I want to let the author say it, but the number of words here is limited, and it is almost 2600 if you don’t count this, so don’t call me short.

　　
　
(End of this chapter)