Siheyuan: I eat melons while doing scientific research

Chapter 1412 Lou Xiao'e's Unbelievable Luck (4k)

Meng Gong looked smugly at the newly transferred comrade in charge of DSP chip programming, who added two characters "*8" to the end of a string of characters.

The string of characters begins with "#define DSP_Freq" and is followed by a number.

DSP chips and C language are Gao Zhendong's two proud achievements in signal processing and computer languages. From the very beginning, the programming language of domestic DSP chips was already firmly bound to C language.

The two additional characters at the end of this string actually mean the same thing: the base frequency of the DSP chip should be multiplied by 8!
"Hey, I have to say, the C language that Committee Member Gao developed is really convenient. Just by adding two characters, the basic frequency parameters of the DSP chip are modified globally." Engineer Meng was delighted. He was happy not only because the C language was easy to use, but also because even if it was convenient, it still had to be usable.

What pleased him most was that his colleagues in the group were quick-witted and applied for the new high-speed digital signal processor in the first instance.

"Hmm, Xiao Zhao, well done, you know what good stuff is." He didn't hold back his praise for the comrade who had "applied" for the new chip.

Xiao Zhao scratched his head: "Engineer Meng, you'd better hurry up and go to the chief engineer to complete the formalities, otherwise I'm afraid I'll be locked up before the afternoon is over."

If someone dares to snatch something from the chief engineer, and the paperwork isn't done in time, the security guards will have something to say.

Meng took out a piece of paper, quickly signed a few words on it, and waved it in front of Xiao Zhao: "Don't worry, it's ready. You're a hero in our group, how can we let a hero bleed and shed tears? I'll take care of anything, I'll get right on it."

The prototype design includes both hardware and software, and these two aspects are developed in parallel. Even if the image is not processed first, the radar itself requires a lot of digital signal processing. For example, the matched filter used for pulse compression is much more convenient to use digitally than analogly, and it is also easier to upgrade and modify.

After all, analog circuits require a lot of circuit modifications, while digital circuits, as long as the sampling accuracy and speed are sufficient, can have many functions added and performance improvements made simply by modifying the program. This is fast, cheap, and convenient.

He was worried that the SAR data was too large to calculate easily, but unexpectedly, good news came from Committee Member Gao, who managed to increase the speed of the DSP chip by eight times!
Amazing! No wonder he dared to start the development of SAR directly. It turns out he had already started preparations in all aspects in advance, and starting SAR was just a natural step.

Meng Gong happily took the application materials and walked towards the chief engineer's office.
-
In the bacteriology laboratory of a medical university, where Lou Xiao'e works, several colleagues are comparing experimental results.

"Senior Sister Lou, there are some problems with these samples," Junior Sister Luo said to Lou Xiao'e, frowning as she looked at the experimental report.

"Where is it? Let me see." Lou Xiao'e took the test report and followed Luo's finger to look at it.

"Hmm, these samples don't contain any Gram-negative bacteria, or even any Gram-positive bacteria, but they still produced a semi-solidified substance..."

This is not good news, as it means that false positive results have been obtained in the testing for Gram-negative bacteria.

But they weren't worried. Research is bound to have problems; smooth sailing is rare. Lou Xiao'e felt that only her husband, Zhendong, often had smooth sailing in his research; otherwise, there was no way to explain where he got so many trophies, awards, and medals.

They began to carefully compare the samples with their numbers, while the other undergraduate students looked at the two senior female students with a hint of admiration. They remained calm and composed, truly impressive.

The two compared the items, exchanged a glance, and a look of delight appeared in their eyes.

"Fungi!!!" The two exclaimed in unison.

That's right, these false positive samples all came from fungal families, but not all fungal families exhibit this phenomenon.

This is a bit troublesome; ambiguous situations are the most difficult to handle.

"Separate the solidified material and use physical and chemical methods to test it, to see what exactly is extra and what reacted with which component in the reagent," Lou Xiao'e said.

"Alright, students, let's get moving! We have another task~~~~" Junior Sister Luo was very cheerful. This wasn't a failure; it was discovering a potential problem and figuring out how to deal with it.

The more often this happens, the more reliable and safe the reagent is in the end.

Three days later, Gao Zhendong was looking at a test report that Lou Xiao'e had brought back. Lou Xiao'e was sitting to his side across the return air furnace, with a child on each of her legs. Three pairs of dark, bright eyes were staring intently at Gao Zhendong.

"How about that? Aren't we awesome?" Lou Xiao'e said happily, her face beaming with pride. In front of Gao Zhendong, she didn't need to be modest. She could be as proud as she wanted, because no matter how proud she was, she couldn't be as proud as Gao Zhendong. So the word "arrogant" had nothing to do with her.

Gao Zhendong nodded: "Yes, impressive!"

Gao Changying, biting into half a steamed bun, said, "Mmm, impressive, impressive."

This isn't just him praising his wife; it's truly remarkable that she was able to find the G factor so quickly—something Gao Zhendong never expected.

Factor G, a component of horseshoe crab blood, can trigger a bypass reaction with fungal polysaccharides in fungi, ultimately resulting in false positives.

Although the report only indicated that a specific compound reacted with lipopolysaccharide, triggering the coagulation phenomenon, and no solution had been found, identifying the culprit so quickly was already a testament to their rapid action.

Now, Lou Xiao'e and Gao Zhendong wanted to discuss whether they had any ideas on how to solve this problem.

Although the current horseshoe crab reagent is usable, it also reacts to fungi, reducing its specificity. Lou Xiao'e and her team felt it was still not good enough.

"Is your reagent based on the original amoeboid cell lysate, and then processed in some way?"

Lou Xiao'e looked astonished: "Hmm, how did you know? We discovered that using reagents purified with chloroform can greatly improve sensitivity, so all our reagents are purified with chloroform."

Gao Zhendong was truly astonished. Holy crap? They even discovered the anti-lipopolysaccharide factor? Gao Zhendong turned to look at the calendar on the wall, confirming it several times. It hadn't been that long.

The presence of anti-lipopolysaccharide factors in horseshoe crab blood can affect the efficacy of factors C and B in horseshoe crab blood, thus affecting the sensitivity of horseshoe crab blood reagents. Therefore, some horseshoe crab blood reagents are treated with chloroform to dissolve and separate the anti-lipopolysaccharide factors in the blood. However, this introduces a problem: chloroform also removes the anti-G factor from the horseshoe crab blood, causing the G factor to become more active. The end result is increased sensitivity, making the interference from fungal polysaccharides more pronounced.

"You've already determined the entire mechanism of action of horseshoe crab blood?" Gao Zhendong was a little incredulous. This didn't make sense. How could it be so fast?

Lou Xiao'e looked at her like she was an idiot: "How could that be? It's not that fast. Didn't you say that we should ignore the mechanism first and just use it? So we're doing both at the same time."

Gao Zhendong was even more puzzled. How could they pinpoint the exact chloroform source when they didn't even know the mechanism? "Then why did you think of using chloroform?"

Lou Xiao'e was a little embarrassed: "Hehe, we're not chemists, and we only have a few organic solvents on hand, so we tried them all. You said that when the options are limited, we can try the exhaustive method, which is a clumsy approach. Unexpectedly, the sensitivity of the reagent increased significantly after chloroform treatment, so we just used it."

Gao Zhendong was both amused and exasperated. Good heavens, this was a real bug—a bunch of bugs could work.

Because the availability of organic solvents is limited, the exhaustive method is not difficult.

Since I happened to have chloroform on hand, I was able to exhaustively search for chloroform.

Even with the addition of different concentrations, the entire experiment is not too complicated.

That's amazing!

This reminded Gao Zhendong of a case he had seen online in his previous life: a patient who survived despite suffering from four serious heart diseases, but whose condition seemed to be mutually dependent. If the patient had been missing even one of these diseases, he would have been long gone.

For a moment, Gao Zhendong didn't know what to say. Luck is also a kind of skill.

However, things didn't end there. Gao Zhendong never expected that he was facing a woman with such incredible luck.

"That's not all. We also discovered that adding trace amounts of calcium and magnesium ions to the reagent can activate the active ingredients in the horseshoe crab reagent, making the reaction faster and more sensitive. Unfortunately, we don't have many inorganic reagents on hand, and calcium and magnesium are relatively common. This discovery was also accidental, hehe."

"Wow, that's impressive, my E'zi," Gao Zhendong exclaimed sincerely. To be able to turn "poverty" into a resource—that's a skill you have to admire!

They stumbled upon this by accident, within a timeframe that Gao Zhendong hadn't anticipated, and successfully developed a practical and mass-producible non-specific horseshoe crab reagent! Here, "non-specific" refers to the fact that the presence of fungal polysaccharides can produce false positives.

Gao Changhe: "E'er is amazing, E'er is amazing."

Lou Xiao'e lightly slapped Gao Changhe on the head, ignoring Gao Changhe's resentful expression of "Why am I always the one who gets hit?", and asked the question that had been bothering her.

Interestingly, the original amoeboid cell lysate was not effective against fungi, but the chloroform-treated solution did have this problem.

Gao Zhendong knew why: if you take away the anti-G factor that suppresses G factor in one go, wouldn't G factor become active?

However, he couldn't say it directly, so he could only hint at it indirectly: "I guess when you used chloroform to treat the reagent, you took away the component that inhibited sensitivity, as well as the component that inhibited the reaction with fungi, and the compounds that these two components target should be similar."

Gao Zhendong's words contained a hint of the correct answer.

Lou Xiao'e's eyes gradually brightened: "Hmm... Now it's clear that the active ingredient in horseshoe crab blood reacts with bacterial endotoxins, which is a type of lipopolysaccharide... So, could it be a sugar from fungi? Fungal polysaccharide?"

Gao Zhendong said, "Perhaps, if that's the case, we know that chemical reactions have a concentration limit. Why don't you try adding a high concentration of fungal polysaccharide directly to the reagent and overwhelm the components that will trigger a coagulation reaction with the fungal polysaccharide!"

Blocking factor G with high concentrations of fungal polysaccharides to render it ineffective is one of the methods for producing specific horseshoe crab reagents, and it is also the simplest and cheapest method. With this treatment, the horseshoe crab reagent becomes ineffective against fungi and is only effective against Gram-negative bacteria.

Lou Xiao'e was a little confused: "You can do that?"

Gao Zhendong laughed and said, "Why not? Let's give it a try. Iron dissolves in dilute sulfuric acid, but not in concentrated sulfuric acid. Isn't that a perfect example?"

Lou Xiao'e was familiar with the example of iron passivating in concentrated sulfuric acid, as it was covered in high school chemistry. Regardless of the underlying principle, Gao Zhendong's simple example undoubtedly boosted Lou Xiao'e's confidence significantly—and it really did!
"Okay, let's try it later." Lou Xiao'e thought they should give it a try, and the experiment was super quick, it was just a matter of adding some concentration.

However, she didn't call this time. Junior Sister Luo is looking for a boyfriend, and it wouldn't be fair to keep leaving this single guy to suffer alone. Let's talk about it tomorrow.
-
National Academy of Sciences, Medical School, Editorial Department of Academic Journals.

"Hey editor, take a look, this submitted article is interesting!" A reviewer pointed to his computer screen, as if he had discovered a new continent.

"What is that? Let me see?" Another comrade walked over from his desk and peeked at his screen.

"A rapid test for Gram-negative bacterial infection? Wow, that's really interesting."

He was immediately drawn to the headline, after all, such methods are simple and reliable, not only domestically but also internationally.

"Is the endotoxin level of 0.08 EU/mL detected after 15-25 minutes, or is it a visual inspection?"

This indicator instantly shocked this well-informed veteran.

Such a low detection limit, such a fast speed, and such a convenient testing method combined are simply unheard of.

This is normal. If it didn't have this effect, horseshoe crabs wouldn't have been driven to extinction so quickly in a few decades.

He snatched the keyboard from the original reviewer and began to turn the pages, reading carefully.

"Ah, horseshoe crab blood. It seems that some people abroad are doing research in this area, but they haven't succeeded yet. How come our comrades in China are so fast?" The original horseshoe crab reagent, even the earliest version, was from 68.

"Yes, the data is comprehensive, the evidence is sufficient, the experiments are complete, and the repeatability is clearly visible. Um... the theoretical mechanism is a little lacking, but the flaws don't detract from the overall excellence, so it's enough. The important thing is that it works!"

The editor-in-chief isn't just sitting around doing nothing; he can tell if a paper is good or not just by touching it and looking at its thickness—the longer it is, the better. But these days, you can't really feel the thickness by touch, since you can't really feel the thickness of things on a computer screen.

He was well aware that, given our current situation, being able to produce something usable was a victory in itself; as for the underlying mechanisms, that could be studied later.

If it were the first of its kind in the world, that would be even better, and this is exactly what we have here.

(End of this chapter)