Hình dưới mô tả cấu trúc của operon lac theo Monod và Jacob:

Theo mô hình này, trong điều kiện có lactose thì RNA polymerase sẽ bám vào vị trí nào để tiến hành phiên mã nhóm gene cấu trúc?

Read the passage and do the tasks below. Choose the best answers to complete the following sentences.

Most people relate stress to physical symptoms like an upset stomach or headaches. Research has suggested that negative emotions and thoughts may also have close links to our brain. Researchers have started finding out why we tend to remember negative things more strongly and, in more detail, than good ones. “The hrain handles positive and negative information in different parts. Negative emotions involve more thinking, and the information is processed more thoroughly. Thus, we tend to ruminate more about unpleasant events and use stronger words to describe them than happy ones," said Clifford Nass, a professor at Stanford University.

Rick Hanson also shares the idea that our minds naturally focus on the bad and discard the good. He stated, "negative stimuli produce more neural activity than do equally intense positive ones. They are also perceived more easily and quickly." This was obtained from his little experiment in which twenty people were asked to look at pictures showing anger or happiness. The participants could identify angry faces faster than happy ones even if it was so quickly.

In a journal article Baumeister co-authored in 2001, "Bad is Stronger Than Good", he concluded, "bad emotions, bad parents and bad feedback have more impact than good ones." This is "a basic and wide-ranging principle of psychology". Thus, Baumeister and his colleagues noted that bad incidents, such as losing your dreamy job and breaking up with your girlfriend or boyfriend, may have a greater impact than landing a job or receiving a marriage proposal.

People have generally related stress to ____.

Quỹ Tiền tệ Quốc tế viết tắt là gì?

Tìm mệnh đề đúng trong các mệnh đề dưới đây?

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the option that best fits each of the numbered blanks from 18 to 22.

     Technology can exert its power on almost every aspect of our lives, and personal relationships are no exception. We are now becoming more attached to technological devices and less connected to the people around us or even our loved ones (18)_________.

     We work longer hours on computers, meet fewer friends, text more often, and watch more videos than have a true conversation with friends or family members. Relationships at home and at work (19)_______. Social media links us all together, but we mistake them for a perfect replacement for relationships. It is time we realised that the power of connections is built from our own efforts. Choosing to stay technologically connected, (20_________, listening, understanding, and sharing feelings. (21)_________.

     It is not difficult to balance between connections through technology and those through real interactions. (22)_________. We should spend more time visiting our parents and siblings, besides keeping in touch with them on social media. We should learn to cherish the moments we spend with them. It is never too late to strengthen the bonds with school friends and teachers.      

Dựa trên cơ sở nào sau đây để phân chia các quốc gia trên thế giới thành nhóm nước phát triển và đang phát triển?

Read the following passage about education in Nepal and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40. 

A few years ago, amid a record drought, scientists noticed something odd. A few of California’s giant sequoias inside Sequoia and Kings Canyon National Parks were dying in ways no one had ever documented – from the top down. When researchers climbed into the canopies, they discovered that beetles had bored into a few branches. By 2019, at least 38 of the trees had died – not a large number, but "concerning because we’ve never observed this before,” says Christy Brigham, the park’s chief of resource management.

Scientists had assumed that stately sequoias, with their bug-repelling tannins, were immune to dangerous pests. Worried experts are investigating whether some mix of increased drought and wildfire, both worsened by climate change, have now made even sequoias susceptible to deadly insect invasions.

If so, these ancient sentinels would be just the latest example of a trend experts are documenting around the world: Trees in forests are dying at increasingly high rates—especially the bigger, older trees. According to a study in the journal Science, the death rate is making forests younger, threatening biodiversity, eliminating important plant and animal habitat, and reducing forests’ ability to store excess carbon dioxide generated by our consumption of fossil fuels. [A]

There is no single direct cause. Decades of logging and land clearing play a role, scientists say. But increasing temperatures and rising carbon dioxide from the burning of fossil fuels have significantly magnified most other causes of tree death. Scientists are documenting longer and harsher droughts, more severe outbreaks of insects and disease, and increasingly catastrophic wildfires.

With 60,000 known tree species on Earth, those shifts are playing out differently across the planet. In central Europe, for instance, “You don’t have to look for dead trees,” says Henrik Hartmann, with Germany's Max Planck Institute for Biogeochemistry. “They’re everywhere.” In one recent year, following a week of excessive heat, hundreds of thousands of beech trees dropped their leaves. Even in colder regions, “You get a couple of hot years and the forests are suffering,” says Hartmann. “There are individual species that are being driven beyond the threshold of what they can handle.” [B]

Just last year, massive fires marched through a dry Australia, smoldered across 7.4 million acres in northern Siberia, and focused the world’s attention on blazes in the Amazon.

The consequences of all these changes around the world are still being assessed. The first national look at tree mortality in Israel showed vast stretches disappearing, thanks largely to scorching heat and wildfires. [C] In a country largely blanketed by stone and sand, forests mean a great deal. Trees support nests for eagles and habitat for wolves and jackals. They hold soil with their roots. [D]

“We’re dealing with a very tough situation. It’s a race to the unknown,” says Tamir Klein at the Weizmann Institute of Science.

What does ‘these ancient sentinels’ in paragraph 3 refer to?

Theo khả năng có thể bị hao kiệt trong quá trình sử dụng của con người, tài nguyên thiên nhiên được chia thành tài nguyên nào?

Chất điểm dao động điều hòa có phương trình vận tốc v = 4πcos2πt (cm/s). Gốc tọa độ ở vị trí cân bằng. Mốc thời gian được chọn vào lúc chất điểm có li độ và vận tốc là:

Read the following passage about urban shift and mark the letter A, B, C, D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.

[I] Sperm whales are fascinating creatures. [II] They possess the biggest brain of any species, six times larger than a human’s, which scientists believe may have evolved to support intelligent, rational behavior. [III] They’re also highly social and capable of making decisions as a group. [IV] But there’s also a lot we don’t know about them, including what they may be saying to one another when communicating with a system of short clicks, known as codas.

Now, new research published in Nature Communications today suggests that sperm whales’ communication is actually much more expressive and complicated than was previously thought. A team of researchers led by Pratyusha Sharma at MIT’s Computer Science and Artificial Intelligence Lab (CSAIL) working with Project CETI, a nonprofit focused on using AI to understand whales, used statistical models to analyze whale codas and managed to identify a structure to their language that’s similar to features of human language. Their findings represent a tool future researchers could use to decipher not just the structure but the actual meaning of whale sounds.

For the study, the researchers examined recordings of 8,719 codas from around 60 whales collected by the Dominica Sperm Whale Project between 2005 and 2018, using a mix of AI algorithms for pattern recognition and classification. The AI then turned the clicks within the coda data into a new kind of data visualization called an exchange plot, revealing that some codas featured extra clicks. These extra clicks, combined with variations in the duration of their calls, appeared in interactions between multiple whales, which they say suggests that codas can carry more information and possess a more complicated internal structure than we had previously believed.

The team’s next step is to build language models of whale calls and to examine how those calls relate to different behaviors. They also plan to work on a more universal system that could be used across species, says Sharma. Taking a communication system we know nothing about, working out how it encodes and transmits information, and slowly beginning to understand what’s being communicated could have many purposes beyond whales. “I think we’re just starting to understand some of these things,” she says. “We’re very much at the beginning, but we are slowly making our way through.”

Which of the following best summarises paragraph 2?

 Đặc trưng cơ bản nhất của cơ chế thị trường là gì?