Saturday, July 24
Ancient Civilizationss
As the men tore down a wall that had been built using the detritus of nearby ancient Egyptian sites, they discovered a large stone fragment covered in three types of writing, including ancient Greek.
Intrigued, Bouchard wondered if the stone might say the same thing in three different languages. He shared his find with French scholars who had come to plumb Egypt for archaeological treasures.
They got more than they bargained for. The slab was the Rosetta Stone, and the letters and symbols carefully chiseled into its dark face would shed light on the glory of ancient Egyptian civilization. But first, scholars would have to crack its code. READ MORE
They got more than they bargained for. The slab was the Rosetta Stone, and the letters and symbols carefully chiseled into its dark face would shed light on the glory of ancient Egyptian civilization. But first, scholars would have to crack its code. READ MORE
Friday, July 23
Milllennials Approve of Communism
Mr. Hernandez’s comments drew the ire of state representative Quang Nguyen (R-Prescott Valley), who, at 12-years-old, left Tan Son Nhut airport in Vietnam a week before the fall of Saigon.
Mr. Nguyen responded to his Democratic colleague’s comments by recounting his own experience as a refugee: “So let me tell you something about white nationalism. White nationalism didn’t drown 250,000 Vietnamese in the South China Sea. The communists did. White nationalism did not execute 86,000 South Vietnamese at the fall of Saigon. Communists did. White nationalism did not put me here. Communism did. So, don’t take it lightly. Don’t mock me. Don’t mock what I go through in life. It’s rough. I lost most of my cousins, my family members due to communism. If we don’t stand up to teach communism to our children, we’ll lose this country. So sir, don’t mock me.” READ MORE
Harris Losing Fans
Tucked at the end of the results are favorability ratings for various political figures, including the vice president.
The poll was conducted July 16-18, with a sample size of 1,997 registered voters and a margin of error of plus or minus 2 percentage points.
Just 45 percent of respondents have a favorable view of Harris, compared to 47 percent who have an unfavorable view.
More men, at 48 percent, have a favorable view of Harris, compared to the 47 percent who have an unfavorable view. Women, however, are not fans of the vice president, with 43 percent having a favorable view, compared to the 47 percent who have an unfavorable view.
So few Republican women, at 3 percent, have a favorable view of Harris, that it’s possible that with the margin of error that the Vice President has virtually no support from the demographic.
Republican women have a more favorable rating of President Joe Biden, at 9 percent.
Those demographics which have equally or even more significant non-support for Harris include the 2 percent favorable ratings from those who strongly disapprove of the job Biden is doing and the 1 percent who have a very unfavorable view of Biden.
The vice president has most of her support from Democrats and Liberals, at 85 percent each, as well as from 86 percent of Democratic women. Slightly more of respondents who voted for Hillary Clinton in 2016, at 85 percent, have a favorable view of her than the 82 percent of respondents who voted for Joe Biden in 2020. READ MORE
Adult Brains
(Image caption: A 3-D animated image showing our synapse phagocytosis reporter in mouse hippocampus. Presynapses in green, astrocytes in white, and microglia in blue. Phagocytosed presynapses by glia were shown in red.)
Astrocytes Eat Connections to Maintain Plasticity in Adult Brains
Developing brains constantly sprout new neuronal connections called synapses as they learn and remember. Important connections — the ones that are repeatedly introduced, such as how to avoid danger — are nurtured and reinforced, while connections deemed unnecessary are pruned away. Adult brains undergo similar pruning, but it was unclear how or why synapses in the adult brain get eliminated.
Now, a team of KAIST researchers has found the mechanism underlying plasticity and, potentially, neurological disorders in adult brains. They published their findings in Nature.
“Our findings have profound implications for our understanding of how neural circuits change during learning and memory, as well as in diseases,” said paper author Won-Suk Chung, an assistant professor in the Department of Biological Sciences at KAIST. “Changes in synapse number have strong association with the prevalence of various neurological disorders, such as autism spectrum disorder, schizophrenia, frontotemporal dementia, and several forms of seizures.”
Gray matter in the brain contains microglia and astrocytes, two complementary cells that, among other things, support neurons and synapses. Microglial are a frontline immunity defense, responsible for eating pathogens and dead cells, and astrocytes are star-shaped cells that help structure the brain and maintain homeostasis by helping to control signaling between neurons. According to Professor Chung, it is generally thought that microglial eat synapses as part of its clean-up effort in a process known as phagocytosis.
“Using novel tools, we show that, for the first time, it is astrocytes and not microglia that constantly eliminate excessive and unnecessary adult excitatory synaptic connections in response to neuronal activity,” Professor Chung said. “Our paper challenges the general consensus in this field that microglia are the primary synapse phagocytes that control synapse numbers in the brain.”
Professor Chung and his team developed a molecular sensor to detect synapse elimination by glial cells and quantified how often and by which type of cell synapses were eliminated. They also deployed it in a mouse model without MEGF10, the gene that allows astrocytes to eliminate synapses. Adult animals with this defective astrocytic phagocytosis had unusually increased excitatory synapse numbers in the hippocampus. Through a collaboration with Dr. Hyungju Park at KBRI, they showed that these increased excitatory synapses are functionally impaired, which cause defective learning and memory formation in MEGF10 deleted animals.
“Through this process, we show that, at least in the adult hippocampal CA1 region, astrocytes are the major player in eliminating synapses, and this astrocytic function is essential for controlling synapse number and plasticity,” Chung said.
Professor Chung noted that researchers are only beginning to understand how synapse elimination affects maturation and homeostasis in the brain. In his group’s preliminary data in other brain regions, it appears that each region has different rates of synaptic elimination by astrocytes. They suspect a variety of internal and external factors are influencing how astrocytes modulate each regional circuit, and plan to elucidate these variables.
“Our long-term goal is understanding how astrocyte-mediated synapse turnover affects the initiation and progression of various neurological disorders,” Professor Chung said. “It is intriguing to postulate that modulating astrocytic phagocytosis to restore synaptic connectivity may be a novel strategy in treating various brain disorders.”
Past Life on Mars
The space agency's Curiosity rover made the surprising discovery while investigating clay-rich sedimentary rocks around its landing site in Gale Crater, a former lake that was made when an asteroid struck the Red Planet roughly 3.6 billion years ago.
Clay is a good signpost towards evidence of life because it's usually created when rocky minerals weather away and rot after contact with water — a key ingredient for life. It is also an excellent material for storing microbial fossils.
But when Curiosity took two samples of ancient mudstone, a sedimentary rock containing clay, from patches of the dried-out lake bed, dated to the same time and place (3.5 billion years ago and just 400m apart), researchers found that one patch contained only half the expected amount of clay minerals.
Instead, that patch held a greater quantity of iron oxides, the compounds that give Mars its rusty hue. TO READ MORE
China Rivaling Airbus and Boeing
he airline industry is dominated by European planes like the Airbus and the American-made Boeing, which are battling the aviation market against China’s aircraft manufacturer Comac. The company has been testing a new passenger jet called the C919 for short-haul flights, and the C929 for long-haul.
It’s all part of the Chinese government’s Made in China 2025 strategy, which aims to reduce China’s dependence on foreign technology.
“National airlines have long been a marker of a state’s status and prestige in the international sphere, so it’s not surprising to see a new airline in China as its importance and influence in global affairs grows,” said Michelle Murray, a professor and chair at the political studies program at Bard College in New York. TO READ MORE
“National airlines have long been a marker of a state’s status and prestige in the international sphere, so it’s not surprising to see a new airline in China as its importance and influence in global affairs grows,” said Michelle Murray, a professor and chair at the political studies program at Bard College in New York. TO READ MORE
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