Galaxies like the Milky Way are thought to have been built through a series of mergers, drawing in smaller galaxies and clusters of stars and making these foreign stars their own. In some cases, the mergers were recent enough that we can still detect the formerly independent object as a cluster of stars orbiting the Milky Way together. But, as time goes on, interactions with the rest of the stars in the Milky Way will slowly disrupt any structures the cluster incorporates.

 

So it's a bit of a surprise that researchers found what appear to be the remains of a globular cluster composed of some of the oldest stars around. The finding is consistent with a "growth through merger" model of galaxy construction, but it raises questions about how the cluster stayed intact for as long as it did.

Data-mining Gaia

The results started with an analysis of data from the ESA's Gaia mission, which set out to do nothing less than map the Milky Way in three dimensions. Gaia imaged roughly a billion objects dozens of times, enough to estimate both their location and their motion around the Milky Way's core. This map has helped scientists identify structures within our galaxy based on the fact that there are some groups of stars that are not only physically close to each other, but all moving in the same direction.

 

The process of mining the Gaia data for these sorts of structures is so useful that there's a software algorithm called STREAMFINDER that identifies them. That software led to the discovery of the C-19 stellar stream, a group of stars moving together through the Milky Way's halo.

 

One way to check whether these groups of stars really started out as part of a single cluster is to check their age; clusters are often composed of stars with similar ages. One of the ways to see if stars formed at the same time is to check the content of heavier elements. There was little in the way of elements heavier than helium formed during the Big Bang, so most heavy elements that are now present were produced by earlier stars. The later in the history of the Universe a star formed, the more of these heavier elements that star is likely to contain.

 

(Astronomers call any element heavier than helium a metal and refer to a star's heavy-element content as its metallicity. But this will probably confuse most non-astronomers, so we'll avoid it.)

 

So, the astronomers behind the new work measured the levels of heavy elements in the stars that were thought to belong to the C-19 stream. And, with the exception of one outlier, they were all quite similar, suggesting that the stream really is the disrupted remnant of a cluster. But the results also contained a surprise: a remarkably low amount of heavy elements.

Ancient history

The typical way of registering heavy elements is through the ratio of iron (which is only formed late in the life of massive star) to hydrogen. Hydrogen has always been the most abundant element in the Universe, while iron levels have slowly built over time. So the higher the iron-to-hydrogen ratio, the more recently the star formed.

 

In the case of the C-19 stream, the ratio was extremely low. So low, that the stars of C-19 would have formed prior to 3 billion years after the Big Bang, or when the Universe was only about a quarter of its current age. And they likely formed quite a bit earlier than that.

 

Within the Milky Way, a few hundred stars have been identified with similarly low heavy-element levels. But no cluster in which every star has such a low level has ever been seen. In fact, prior to this discovery, clusters in the Milky Way were thought to have a heavy-element floor—all of them had levels above those seen in the C-19 stream. This was true despite the fact that, based on the distribution of known clusters, we'd expect about five with heavy-element levels similar to that of the C-19 stream.

 

The lack of other clusters suggests that most of the earliest clusters like this stream have already been disrupted to the point that they've faded into the background of Milky Way stars. Which raises the question of why the C-19 stream hasn't. That's especially unexpected given that the stream's orbit around the galactic core takes it deep inside the Milky Way, giving it plenty of chances to engage in interactions with other features that should disrupt it.

 

One possibility that could explain this is that the cluster originally entered the Milky Way as part of a dwarf galaxy that was swallowed. The dwarf galaxy's structure could provide a degree of protection until it became disrupted and its stars spread through the Milky Way. And, if this were true, then the cluster that gave rise to the C-19 stream would have had a large fraction of the stars present in the dwarf galaxy at the time.

 

Regardless of how it ends up being explained, the presence of the C-19 stream tells us things about the history of the Universe. "The very existence of C-19 proves that globular clusters must have been able to form in the lowest-metallicity environments as the first galactic structures were assembling," the researchers conclude.

 

Nature, 2022. DOI: 10.1038/s41586-021-04162-2  (About DOIs).

Nine days after the launch of the James Webb Space Telescope, NASA says it has made good progress deploying the $10 billion instrument and has now begun the critical process of "tensioning" the sunshield.

 

On Monday, six motors on board the telescope began the process of fully extending the first of five layers of the sunshield. These tennis-court sized layers, each made of a polyimide film called Kapton, will shade the instrument and allow it to cool down to 50 Kelvin, which is -223 degrees Celsius and just 50 degrees above absolute zero. This cold environment is critical for Webb to observe infrared light and detect heat from very distant objects.

 

NASA's Webb project manager, Bill Ochs, said the first of these five layers should be completely deployed by the end of Monday. The goal is to extend the other four layers on Tuesday and Wednesday. After this time, the massive sunshield—the most complex aspect of an intricate deployment process—will be complete.

 

"I don't expect any drama," said Ochs of the next few days during a teleconference with reporters on Monday.

 

Following this sequence, NASA will be most of the way there. All told, from launch through commissioning, the Webb instrument must undergo 344 actions where a single-point failure could scuttle the telescope. Following sunshield deployment, Ochs said the Webb instrument will be through "70 to 75 percent" of these single-point failures.

 

The other major activities yet to be completed are the deployment of the secondary mirror support structure and the unfolding of the second of Webb's primary mirror wings. These activities could both be finished by this weekend and would effectively complete the deployment phase.

 

Although science operations will not begin until mid-2022, NASA engineers and thousands of scientists will then start to breathe a sigh of relief. It took 20 painstaking years to get Webb into space, and after fewer than 20 days, the telescope will either be fully deployed—or it won't.

 

As part of the deployment process, teams of engineers and scientists at NASA and the telescope's primary contractor, Northrop Grumman, have been working 12-hour shifts since the Christmas Day launch on an Ariane 5 rocket. Over the weekend, the teams worked on two relatively minor issues, said Amy Lo, the James Webb Space Telescope alignments engineer at Northrop.

 

 

The first issue concerned the performance of the telescope's 6-meter-wide solar array. Although the observatory was never "power starved," Lo said the original configuration of the five panels proved not to be optimal. To reach full power, she said, the array was rebalanced, and they are now performing as intended. This is not expected to be an issue going forward.

 

The other potential problem concerned the six motors involved in the tensioning process. They were "running a bit hot," Lo said, but after the telescope was repositioned to keep them cooler, they are at 327 Kelvin, well below the operating limit of 340 Kelvin. Lo said she expects the motors to remain under the limit during the next three days.

On January 2, 1890, a Portuguese man named Jose Antonio Sampaio, Jr., died in terrible agony while staying at the Grand Hotel de Paris in Porto, Portugal. The son of a wealthy and highly respected linen merchant, Sampaio Jr. showed signs of poisoning in his final hours, including blood in his vomit. He was attended by his brother-in-law, a physician named Vicente Urbino de Freitas.

 

Sampaio Jr. was nonetheless buried without incident, and the family might have grieved their loss and moved on. But in late March, Sampaio Jr.'s son and two nieces suddenly became ill after eating almonds with liquor and coconut and chocolate cakes, which had arrived at the Sampaio house on Flores Street via a mysterious package. The children's uncle, the aforementioned de Freitas, prescribed lemon balm enemas. While the girls recovered, 12-year-old Mario Guilherme Augusto de Sampaio died in spasms and convulsions on April 2.

 

Once again, the symptoms were consistent with poisoning, and suspicion soon fell on de Freitas. He was arrested, tried, and convicted in 1893, although he maintained his innocence for the rest of his life. This was the infamous "Crime of Flores Street" and it made headlines around the world. The case continues to fascinate Ricardo Jorge Dinis-Oliveira, a forensic toxicologist at the University of Porto, more than 130 years later, because it gave birth to forensic toxicology studies in Portugal and still informs present-day Portuguese medico-legal procedures. It's also one hell of a story: "It will certainly make a good movie," Dinis-Oliveira wrote.

 

Dinis-Oliveira has spent the last 14 years poring over historical works, trial transcripts, and newspaper accounts from all over the world, even interviewing living relatives of the main characters. He compiled his findings into three separate papers. The first, published in 2018, retold the basic facts of the case. The second, published in 2019, analyzed all the relevant and contradictory testimonial evidence from the trial. Dinis-Oliveira then reviewed the contradictory toxicological evidence in a third paper published in May 2021 in Forensic Sciences Research, defending the professional reputations of his 19th century compatriots.

Two mysterious deaths

Born on Flores Street in Porto in 1849, de Freitas married Maria das Dores Basto Sampaio in 1877, the same year ha became a lecturer at the Medical-Surgical School of Porto. He gained professional distinction over the years with notable studies on dermatology, particularly the treatment of leprosy and syphilis. Perhaps de Freitas hoped to one day inherit his in-laws' considerable wealth. Standing in his way were the couple's three children—an eldest son, Guilherme, who died young; a daughter; and the aforementioned Sampaio Jr.—as well as the three grandchildren.

 

Sampaio Jr.'s wife died young, leaving him with two small daughters. The girls lived with their grandparents while their father became something of an itinerant bohemian, much to his father's disapproval. He took up with an Englishwoman named Lothie Karter, whom he had net at a nightclub in Lisbon. Sampaio Jr. often complained of stomach and liver ailments. He received a mysterious package in October 1898 while still in Lisbon, containing vials purportedly holding medicines to treat those ailments. Not recognizing the sender, Sampaio Jr. did not take the remedies, telling Karter he suspected it was prussic acid (a strong poison).

 

In December 1889, Sampaio Jr. and Karter returned to Porto and moved into the Grand Hotel de Paris. On December 28, Sampaio Jr. had lunch with de Freitas, and became ill the following day. While he initially assumed it was a cold, his condition worsened, and de Freitas was called in to consult. De Freitas gave his brother-in-law a shot of what he said was pilocarpine (now a common treatment for glaucoma).

 

Sampaio Jr. soon became delirious, sweating and shaking, with fever, loss of vision, and vomiting, among other symptoms. Nonetheless, de Freitas insisted on giving him a second injection.  As Sampaio Jr. continued to worsen, de Freitas prescribed one last injection of pilocarpine on the afternoon of January 2, mixing the tincture himself with his back to others in the room. He asked another doctor to administer the shot.

 

The injection site soon developed a nasty black spot. Sampaio Jr. began vomiting violently, and finally died around 6 PM. Before he did so, he told Karter that he was convinced it was the shots of pilocarpine that had sickened him. De Freitas insisted on disposing of the vomit. When the hotelier expressed regret that the man had died so young, de Freitas allegedly told him that his brother-in-law had been "a madman, a scoundrel, who shamed the family," adding, "Didn't you notice the evidence of mental illness? His whole family is like this. They all die by the same way."

 

Then the three young children fell ill, with 12-year-old Mario experiencing convulsions and eventually falling into a coma and dying. The two girls had similar but less severe symptoms—perhaps because they had eaten less of the almonds and cakes. One of the doctors called in to consult thought poisoning seemed likely, perhaps by opium or belladonna.

 

In light of young Mario's suspicious death, the remains of Sampaio Jr. were exhumed so an autopsy could be performed. However, the body was in such an advanced state of decomposition after three months in the ground that it was impossible to make a determination with regard to any injury that might have led to his death, and no toxic substances were found in the liquefied remains of the man's stomach, intestines, lungs, and heart. The same was done for the remains of Mario, and this time the experts did find evidence of lethal amounts of morphine and delphinine (two toxic plant alkaloids), as well as an opium alkaloid called narceine in the viscera and urine.

 

De Freitas was arrested on April 16, 1890 and charged with the murder by poisoning of Mario. There were also rumors that de Freitas had also poisoned a banker, and a rival professor at the Medical-Surgical School of Porto who had died three years earlier, although no evidence was ever produced to corroborate those rumors.

 

Trial of the century

The prosecution assembled a fairly damning case. The police investigation revealed that de Freitas had bought a box of almonds and chocolate cookies during a March 1890 visit to Lisbon; the confectionery clerk recognized him. The doorman of the Lisbon hotel where de Freitas was staying testified that the physician had asked where he could buy almonds for his "fiancee." He then allegedly posed as a man named Eduardo Motta, and convinced a merchant he met on the train to mail the package to his in-laws' home in Porto, apparently to give himself an alibi. At trial, the merchant identified de Freitas as the man he knew as Motta.

 

De Freitas himself agreed that his nephew had been poisoned, "but there was no crime." He claimed a "double" had asked the merchant to mail the package of sweets. De Freitas said he had gone to Lisbon to rendezvous with a married woman on March 6, returning the same day.  He went back to Lisbon on March 7-8, supposedly consulting with a close friend and colleague, Francisco Adolfo Coelho, about a medical translation. Coelho denied this visit at trial, however, and testified that de Freitas had actually written to him asking him to lie about it should he be questioned by police. (He even saved the letter.)

 

Certainly de Freitas's grieving mother-in-law, Maria Carolina Basta Sampaio, was convinced of his guilt. She testified that de Freitas had asked her to lie about his treating and prescribing the enema treatments for the children, as well as trying to cast suspicion on a maternal uncle who lived in Lisbon. But de Freitas' wife, Maria, remained devoted and loyal throughout the trial, sobbing and fainting when the guilty verdict was read.

 

De Freitas was sentenced to eight years in prison in Lisbon, followed by 20 years of exile. His son, Urbino Emilio Basto de Sampaio de Freitas, committed suicide in shame over his father's conviction. While Maria's family offered her family a pension, given their loss of income, she rejected the offer.  De Freitas finally returned to Portugal in 1913, intent on proving his innocence, but he died of pneumonia shortly thereafter, still waiting for a judicial review. Maria de Freitas lived another 43 years, dying in 1956 at the age of 97.

 

The verdict was not unanimous, however, so not all jurors were convinced that de Freitas was guilty. Some of the witness testimony was contradictory, particularly with regard to whether de Freitas was in Lisbon or Porto on the key date of March 28. Also, the public prosecutor had been a former (unsuccessful) suitor of de Freitas' wife, raising the possibility that he was motivated by personal animosity toward the defendant. Finally, there was considerably controversy over the various toxicological reports.

War of the Experts

Was de Freitas a "monster" who was truly guilty of murder, or a martyr to an overzealous prosecution? It's a question that would have a fairly straightforward answer today given modern toxicological methods, according to Dinis-Oliveira. But back in the late 19th century, "the unmistakable detection of morphine, narceine, and delphinine seems somewhat very difficult in light of the scientific advances of the time," Dinis-Oliveiras wrote in his 2018 paper.

 

The expert evidence presented at trial was questioned at the time by an advisory judge, who noted the lack of input from foreign toxicologists. So several foreign experts were also invited to weigh in, including Louis Lewin, who pioneered the study of psychoactive plants. Unfortunately, "All these consultations were unfavorable to the work and conclusions of the official experts, extensively highlighting the ("inexcusable") errors and the presence of putrefaction products that were allegedly confused with toxic plant alkaloids, as well as the abuse and misunderstanding of the use of analytical methods," Dinis-Oliveiras wrote in his 2021 paper. Several rebutted the finding of morphine and delphinine in Mario's viscera and vomit.

 

Dinis-Oliveiras takes issue with this characterization of the Portuguese experts' work. Much of this latest paper focuses on the work of Antonio Joaquim Ferreira da Silva, who was "practically chained" to his laboratory for the three years between de Freitas' arrest and trial. (His analysis also concluded that young Mario Sampaio had died of morphine and delphinine poisoning.) Da Silva made several discoveries over the course of that research, per Dinis-Oliveiras, including characterizing new reactions to detect cocaine, serine, and the alkaloids, as well as eserine. Some of these discoveries were presented by his peers at the Paris Academy of Sciences.

 

All of this shows that da Silva "did not act lightly, but worked with the forthrightness of a good toxicology expert," Dinis-Oliveiras wrote, despite being relentlessly attacked and having his scientific reputation questioned throughout the trial. In fact, da Silva's diligence "inaugurated a new phase of toxicology and forensic chemistry in Portugal." Dinis-Oliveiras concludes, "The experts of Porto did a remarkable job that was nearly impossible to rebut considering the knowledge of that time."

 

Without that toxicological evidence, it is unlikely that de Freitas would have been convicted, according to Dinis-Oliveiras. He suggests that even more insight could be gleaned if the remains of at least one supposed victim could be identified. The good news is that Dinis-Oliveiras finally tracked down the location of the corpse of Sampaio Jr. in 2020, and was able to perform a new autopsy. DNA analysis to confirm the corpse's identity, and toxicological analysis testing for morphine, delphinine, or narceine, is underway. The results will be reported in a future paper.

 

DOI: Forensic Sciences Research, 2021. 10.1080/20961790.2021.1898079  (About DOIs).

DOI: Forensic Sciences Research, 2019. 10.1080/20961790.2019.1682218  (About DOIs).

DOI: Forensic Sciences Research, 2018. 10.1080/20961790.2018.1534538  (About DOIs).

The US Constitution requires that a population count be conducted at the beginning of every decade.

 

This census has always been charged with political significance, and continues to be. That’s clear from the controversies in the run-up to the 2020 census.

 

But it’s less widely known how important the census has been in developing the US computer industry, a story that I tell in my book, Republic of Numbers: Unexpected Stories of Mathematical Americans through History. That history includes the founding of the first automated data processing company, the Tabulating Machine Company, 125 years ago on December 3, 1896.

Population growth

The only use of the census clearly specified in the Constitution is to allocate seats in the House of Representatives. More populous states get more seats.

 

A minimalist interpretation of the census mission would require reporting only the overall population of each state. But the census has never confined itself to this.

 

A complicating factor emerged right at the beginning, with the Constitution’s distinction between “free persons” and “three-fifths of all other persons.” This was the Founding Fathers’ infamous mealy-mouthed compromise between those states with a large number of enslaved persons and those states where relatively few lived.

 

The first census, in 1790, also made nonconstitutionally mandated distinctions by age and sex. In subsequent decades, many other personal attributes were probed as well: occupational status, marital status, educational status, place of birth, and so on.

 

As the country grew, each census required greater effort than the last, not merely to collect the data but also to compile it into usable form. The processing of the 1880 census was not completed until 1888.

 

It had become a mind-numbingly boring, error-prone, clerical exercise of a magnitude rarely seen.

 

Since the population was evidently continuing to grow at a rapid pace, those with sufficient imagination could foresee that processing the 1890 census would be gruesome indeed without some change in procedure.

A new invention

John Shaw Billings, a physician assigned to assist the Census Office with compiling health statistics, had closely observed the immense tabulation efforts required to deal with the raw data of 1880. He expressed his concerns to a young mechanical engineer assisting with the census, Herman Hollerith, a recent graduate of the Columbia School of Mines.

 

On Sept. 23, 1884, the US Patent Office recorded a submission from the 24-year-old Hollerith, titled “Art of Compiling Statistics.”

 

By progressively improving the ideas of this initial submission, Hollerith would decisively win an 1889 competition to improve the processing of the 1890 census.

 

The technological solutions devised by Hollerith involved a suite of mechanical and electrical devices. The first crucial innovation was to translate data on handwritten census tally sheets to patterns of holes punched in cards. As Hollerith phrased it, in the 1889 revision of his patent application, “A hole is thus punched corresponding to person, then a hole according as person is a male or female, another recording whether native or foreign born, another either white or colored, &c.”

 

This process required developing special machinery to ensure that holes could be punched with accuracy and efficiency.

 

Hollerith then devised a machine to “read” the card, by probing the card with pins, so that only where there was a hole would the pin pass through the card to make an electrical connection, resulting in advance of the appropriate counter.

 

For example, if a card for a white male farmer passed through the machine, a counter for each of these categories would be increased by one. The card was made sturdy enough to allow passage through the card reading machine multiple times, for counting different categories or checking results.

 

The count proceeded so rapidly that the state-by-state numbers needed for congressional apportionment were certified before the end of November 1890.

 

Rise of the punched card

After his census success, Hollerith went into business selling this technology. The company he founded, the Tabulating Machine Company, would, after he retired, become International Business Machines—IBM. IBM led the way in perfecting card technology for recording and tabulating large sets of data for a variety of purposes.

 

By the 1930s, many businesses were using cards for record-keeping procedures, such as payroll and inventory. Some data-intensive scientists, especially astronomers, were also finding the cards convenient. IBM had by then standardized an 80-column card and had developed keypunch machines that would change little for decades.

 

Card processing became one leg of the mighty computer industry that blossomed after World War II, and IBM for a time would be the third-largest corporation in the world. Card processing served as a scaffolding for vastly more rapid and space-efficient purely electronic computers that now dominate, with little evidence remaining of the old regime.

 

Those who have grown up knowing computers only as easily portable devices, to be communicated with by the touch of a finger or even by voice, may be unfamiliar with the room-size computers of the 1950s and ’60s, where the primary means of loading data and instructions was by creating a deck of cards at a keypunch machine, and then feeding that deck into a card reader. This persisted as the default procedure for many computers well into the 1980s.

 

As computer pioneer Grace Murray Hopper recalled about her early career, “Back in those days, everybody was using punched cards, and they thought they’d use punched cards forever.”

 

Hopper had been an important member of the team that created the first commercially viable general-purpose computer, the Universal Automatic Computer, or UNIVAC, one of the card-reading behemoths. Appropriately enough, the first UNIVAC delivered, in 1951, was to the US Census Bureau, still hungry to improve its data processing capabilities.

 

No, computer users would not use punched cards forever, but they used them through the Apollo Moon-landing program and the height of the Cold War. Hollerith would likely have recognized the direct descendants of his 1890s census machinery almost 100 years later.

Among the many popular tourist sites in Rome is an impressive 2000-year-old mausoleum along the Via Appia known as the Tomb of Caecilia Metella, a noblewoman who lived in the first century CE. Lord Byron was among those who marveled at the structure, even referencing it in his epic poem Childe Harold's Pilgrimage  (1812-1818). Now scientists have analyzed samples of the ancient concrete used to build the tomb, describing their findings in a paper published in October in the Journal of the American Ceramic Society.

 

“The construction of this very innovative and robust monument and landmark on the Via Appia Antica indicates that [Caecilia Metella] was held in high respect,” said co-author Marie Jackson, a geophysicist at the University of Utah.  “And the concrete fabric 2,050 years later reflects a strong and resilient presence.”

 

Like today's Portland cement (a basic ingredient of modern concrete), ancient Roman concrete was basically a mix of a semi-liquid mortar and aggregate. Portland cement is typically made by heating limestone and clay (as well as sandstone, ash, chalk, and iron) in a kiln. The resulting clinker is then ground into a fine powder, with just a touch of added gypsum—the better to achieve a smooth, flat surface. But the aggregate used to make Roman concrete was made up fist-size pieces of stone or bricks

 

In his treatise de Architectura (circa 30 CE), the Roman architect and engineer Vitruvius wrote about how to build concrete walls for funerary structures that could endure for a long time without falling into ruins. He recommended the walls be at least two feet thick, made of either "squared red stone or of brick or lava laid in courses."  The brick or volcanic rock aggregate should be bound with mortar comprised of hydrated lime and porous fragments of glass and crystals from volcanic eruptions (known as volcanic tephra).

 

Jackson has been studying the unusual properties of ancient Roman concrete for many years. For instance, she and several colleagues have analyzed the mortar used in the concrete that makes up the Markets of Trajan, built between 100 and 110 CE (likely the world's oldest shopping mall). They were particularly interested in the "glue" used in the material's binding phase: a calcium-aluminum-silicate-hydrate (C-A-S-H), augmented with crystals of stratlingite. They found that the stratlingite crystals blocked the formation and spread of microcracks in the mortar, which could have led to larger fractures in the structures.

 

In 2017, Jackson co-authored a paper analyzing the concrete form the ruins of sea walls along Italy's Mediterranean coast, which have stood for two millennia despite the harsh marine environment. The constant salt-water waves crashing against the walls would have long ago reduced modern concrete walls to rubble, but the Roman sea walls seem to have actually gotten stronger.

 

Jackson and her colleagues found that the secret to that longevity was a special recipe, involving a combination of rare crystals and a porous mineral. Specifically, exposure to sea water generated chemical reactions inside the concrete, causing aluminum tobermorite crystals to form out of phillipsite, a common mineral found in volcanic ash. The crystals bound to the rocks, once again preventing the formation and propagation of cracks that would have otherwise weakened the structures.

 

So naturally Jackson was intrigued by the Tomb of Caecilia Metella, widely considered to be one of the best-preserved monuments on the Appian Way. Jackson visited the tomb back in June 2006, when she took small samples of the mortar for analysis. Despite the day of her visit being quite warm, she recalled that once inside the sepulchral corridor, the air was very cool and moist. "The atmosphere was very tranquil, except for the fluttering of pigeons in the open center of the circular structure," Jackson said.

 

Almost nothing is known about Caecilia Metella, the noblewoman whose remains were once interred in the tomb, other than that she was the daughter of a Roman consul, Quintus Caecilius Metellus Creticus. She married Marcus Licinius Crassus, whose father (of the same name) was part of the First Triumvirate, along with Julius Caesar and Pompey the Great. It was likely her son—also named Marcus Licinius Crassus, because why make it easy for historians to keep track of the family genealogy?—who ordered the construction of the mausoleum, likely built sometimes between 30 and 10 BCE.

 

A marble sarcophagus housed in Palazzo Farnese is supposedly from the Tomb of Caecilia Metella, but it was probably not the noblewoman's since it dates to between 180 and 190 CE.  Besides, cremation was a more common burial custom at the time of the lady's demise, and thus historians believe that the tomb's cella probably once held a funerary urn, rather than some kind of sarcophagus.

 

It's the structure of the the tomb itself that is of most interest to scientists like Jackson and her colleagues. The mausoleum is perched atop a hill. There is a cylindrical rotunda atop a square podium, with an attached castle to the rear that was built sometime in the 14th century. The exterior bears a plaque with the inscription, "To Caecilia Metella, daughter of Quintus Creticus [and wife] of Crassus."

 

The foundation is built partly on tuff rock (volcanic ash that has been compacted under pressure) and lava rock from an ancient flow that once covered the area some 260,000 years ago. The podium and rotunda are both comprised of several layers of thick concrete, surrounded by travertine blocks as a frame while the concrete layers formed and hardened. The tower walls are 24 feet thick. Originally there would have been a conical earthen mound on top, but it was later replaced with medieval battlements.

 

To take a closer look at the tomb mortar's microstructure, Jackson teamed up with MIT colleagues Linda Seymour and Admir Masic, as well as Lawrence Berkeley Lab's Nobumichi Tamura. Tamura analyzed the samples at the Advanced Light Source, which helped them identify both the many different minerals contained in the samples and their orientation. The ALS beam line produces powerful x-ray beams about the size of a micron, which can penetrate through the entire thickness of the samples, per Tamura. The team also imaged the samples with scanning electron microscopy.

 

They discovered that the tomb's mortar was similar to that used in the walls of the Markets of Trajan: volcanic tephra from the Pozzolane Rosse pyroclastic flow, binding together large chunks of brick and lava aggregate. However, the tephra used in the tomb's mortar contained much more potassium-rich leucite. Over the centuries, rainwater and groundwater seeped through the tomb's walls, which dissolved the leucite and released the potassium. This would be a disaster in modern concrete, producing micro-cracking and serious deterioration of the structure.

 

That obviously didn't happen with the tomb. But why? Jackson et al. determined that the potassium in the mortar dissolved in turn and effectively reconfigured the C-A-S-H binding phase. Some parts remained intact even after over 2000 years, while other areas looked more wispy and showed some signs of splitting. In fact, the structure somewhat resembled that of nanocrystals.

 

“It turns out that the interfacial zones in the ancient Roman concrete of the tomb of Caecilia Metella are constantly evolving through long-term remodeling," said Masic. “These remodeling processes reinforce interfacial zones and potentially contribute to improved mechanical performance and resistance to failure of the ancient material.”

 

The more scientists learn about the precise combination of minerals and compounds used in Roman concrete, the closer we get to being able to reproduce those qualities in today's concrete—such as finding an appropriate substitute (like coal fly ash) for the extremely rare volcanic rock the Romans used. This could reduce the energy emission of producing concrete by as much as 85 percent, and improve significantly on the lifespan of modern concrete structures.

 

“Focusing on designing modern concretes with constantly reinforcing interfacial zones might provide us with yet another strategy to improve the durability of modern construction materials,” said Masic. “Doing this through the integration of time-proven ‘Roman wisdom’ provides a sustainable strategy that could improve the longevity of our modern solutions by orders of magnitude.”

 

DOI: Journal of the American Ceramic Society, 2021. 10.1111/jace.18133  (About DOIs).

When fully operational, the James Webb Space Telescope will be enormous, with a sun shield measuring 12 x 22 meters. Obviously, however, it can't be sent to space in that configuration. As a result, the tension of the launch will be followed by weeks of equally nerve-wracking days as different parts of the observatory are gradually unfolded.

 

The good news is that the process has already started, and everything has gone off without a hitch so far. Meanwhile, NASA has analyzed the results of the initial firings of the observatory's on-board rockets, and determined that it will have enough fuel for "significantly more" than a decade of operations.

Good news on fuel

The Webb will orbit a position called the L2 Lagrange point, a site about 1.4 million kilometers from Earth. Getting into that orbit requires moving outside the plane defined by the Earth's orbit around the Sun, and arriving at shallow angle so that the Webb doesn't overshoot its target.

 

To reach the appropriate trajectory, the Webb is relying on both the initial course set by its Ariane 5 launch vehicle and a series of course adjustments powered by its onboard engines. Those onboard engines will later be responsible for making adjustments to keep the Webb in its orbit and properly oriented for observations. The more efficiently the first bits get done, the more of the latter Webb will be able to do with the remaining fuel.

 

The Webb has now done two course-correction firings, and its controllers have analyzed the results and the amount of fuel used. Their results? "The observatory should have enough propellant to allow support of science operations in orbit for significantly more than a 10-year science lifetime."

 

The Webb team largely credit this to the Ariane 5 launcher, which greatly exceeded the minimum requirements needed to put Webb on the correct course, and a successful first course adjustment.

 

The launch vehicle's performance also explains a little oddity that took place shortly after the observatory separated from the launch vehicle, when the Webb's solar panel deployed sooner than expected. It turns out that the panels could deploy whenever the telescope had reached the right orientation relative to the Sun to produce significant power. The launch vehicle did such a good job of orienting the Webb that this happened sooner than expected, leading to the rapid extension of the panels.

Unfolding drama-free

Meanwhile the process of putting the Webb into its operational configuration has continued. The Webb's sun shield will need to go through five distinct processes to reach its final configuration, and the first two of these are now complete. For launch, it was stowed as if it were compressed then folded in half around the telescope hardware.

 

In separate steps, the front and rear portions of the sun shield have now unfolded, bringing Webb to its full length for the first time since it was on Earth. The next steps there will involve extending the left and right sides, then separating out the different layers of the sun shield and adding tension that will extend them to their full size. It will be about five days before this process is complete.

 

Still, with the sun shield at least partially functional, NASA has now added temperature data to the "Where is Webb?" tracking website. Even without any cooling hardware operating, and without the sun shield at its full extension, the hot and cold extremes of the observatory now differ by over 160º C.

 

Separate from the sun shield, there's another hardware change happening as this story's being written. The telescope itself sits on a pedestal that raises it above the sun shield and affords it a greater field of view. As with most other hardware, that pedestal, the Deployable Tower Assembly, was in a compact position for launch; it's now being put in its fully extended configuration. NASA says that it could take as many as six hours to complete this process.

 

Update: The extension of the Deployable Tower Assembly has completed successfully.

You’ve probably heard it before: drinking coffee is good for your health. Studies have shown that drinking a moderate amount of coffee is associated with many health benefits, including a lower risk of developing type 2 diabetes and cardiovascular disease. But while these associations have been demonstrated many times, they don’t actually prove that coffee reduces disease risk. In fact, proving that coffee is good for your health is complicated.

 

While it’s suggested that consuming three to five cups of coffee a day will provide optimal health benefits, it’s not quite that straightforward. Coffee is chemically complex, containing many components that can affect your health in different ways.

 

While caffeine is the most well-known compound in coffee, there is more to coffee than caffeine. Here are a few of the other compounds found in coffee that might affect your health.

 

Alkaloids. Aside from caffeine, trigonelline is another important alkaloid found in coffee. Trigonelline is less researched than caffeine, but research suggests that it may have health benefits, such as reducing the risk of type 2 diabetes.

 

Polyphenols. Some research shows that these compounds, which are found in many plants, including cocoa and blueberries, are good for your heart and blood vessels, and may help to prevent neurodegenerative diseases such as Alzheimer’s. Coffee predominantly contains a class of polyphenols called chlorogenic acids.

 

Diterpenes. Coffee contains two types of diterpenes – cafestol and kahweol – that make up coffee oil, the natural fatty substance released from coffee during brewing. Diterpenes may increase the risk of cardiovascular disease.

 

Melanoidins. These compounds, which are produced at high temperatures during the roasting process, give roasted coffee its color and provide the characteristic flavor and aroma of coffee. They may also have a prebiotic effect, meaning they increase the amount of beneficial bacteria in your gut, which is important for overall health.

 

The way your coffee is grown, brewed and served can all affect the compounds your coffee contains and hence the health benefits you might see.

 

First, growing conditions can affect the levels of caffeine and chlorogenic acids the coffee contains. For example, coffee grown at high altitudes will have both lower caffeine and chlorogenic acid content. The two types of coffee beans, arabica and robusta, have also been shown to have different caffeine, chlorogenic acid and trigonelline levels. Although neither type has been shown to be more beneficial to health.

 

The extent that coffee is roasted is also key. The more severe the roasting, the more melanoidins formed (and the more intense the flavor). But this lowers chlorogenic acids and trigonelline content.

 

In the UK, instant coffee is the most commonly consumed type of coffee. This is typically freeze-dried. Research shows that instant coffee contains higher levels of melanoidins per serving compared with filter coffee and espresso.

 

How you prepare your coffee will also affect its chemical composition. For example, boiled coffee contains a higher level of diterpenes compared with filter coffee. Other factors—such as the amount of coffee used, how finely it was ground, water temperature and cup size—will also affect the coffee’s chemical composition.

Health effects

Every compound has different effects on your health, which is why the way coffee is produced and brewed can be important.

 

Chlorogenic acids, for example, are thought to reduce the risk of cardiovascular disease by improving the function of your arteries. There’s also evidence they may reduce the risk of type 2 diabetes by controlling blood sugar spikes after eating.

 

On the other hand, diterpenes have been shown to increase levels of low-density lipoprotein, a type of cholesterol associated with cardiovascular disease. While less research has focused on trigonelline and melanoidins, some evidence suggests both may be good for your health.

 

Adding cream, sugar and syrup will change the nutritional content of your cup. Not only will they increase the calorie content, they may also increase your intake of saturated fats and sugars. Both of these are associated with increased risk of type 2 diabetes and cardiovascular disease and may counter the beneficial effects of the other compounds your cup of coffee contains.

 

There’s also evidence that people may respond differently to some of these compounds. Regularly drinking three to four cups of coffee daily has been shown to build tolerance to the blood pressure raising effects of caffeine. Genetics may also play a role in how your body handles caffeine and other compounds.

 

Increasing evidence also points to the gut microbiome as an important factor in determining what health effects coffee may have. For example, some research suggests the gut microbes play an important role in chlorogenic acid metabolism, and hence may determine if they will benefit your health or not.

 

Researchers need to conduct large studies to confirm the findings of these smaller studies, which seem to show that coffee is good for your health. But in the meantime, minimize the sugar and cream you use in your coffee. And if you’re in good health and aren’t pregnant, continue to take a moderate approach to coffee consumption, choosing filter coffee where possible.

Space Telescope Science Institute, Baltimore, MD -- Today, the James Webb Space Telescope started its journey to a location over a million kilometers from Earth, where it will start its science mission in roughly six months. "This is a day for the ages," said Ken Sembach, director of the Space Telescope Science Institute. "Science won't be the same after today."

 

Sembach said those words roughly an hour before the launch, well before any last minute glitches could have delayed matters, and long before the complicated series of events that would see parts of the observatory unfold from their compact launch configuration. After years of delays, and so much riding on these events, you might expect a greater sense of tension among those gathered here to watch the launch, but the people gathered at the Space Telescope Science Institute seemed remarkably relaxed. At least until you asked them how they were feeling.

 

And, so far at least, that confidence appears to be well placed. The launch countdown went forward without delay, and each step along the way—separating of solid rocket boosters, release of the fairing—went exactly as planned, and the rocket tracked exactly along the planned trajectory. Video from the rocket's second stage showed the telescope's solar panel deploy, and shortly after controllers here indicated it was fully powered.

What's to come

Scott Friedman, the Webb's commissioning scientist, went over all the additional hurdles that the telescope has to clear before it's operational, a milestone that's expected to take place in six months. Over the first few weeks, the sunscreen will be extended to its full width, and then the screen's multiple layers will separate and then be pulled to a tension sufficient to stretch them into their final form. Following that, a tower will extend the instrument package away from the "hot side" of the telescope facing the Sun.

 

On the hot side, there's a solar panel, communication equipment, and all the hardware needed to function as a spacecraft. These have to be kept separated from the infrared imaging equipment, lest the heat they generate swamp any signals in the telescope.

 

The cool side will start deploying after the sunscreen, starting with the small secondary mirror that's housed on booms extending in front of the primary mirror. The two wings of the primary mirror, folded back to fit in the launch fairing, will then extend, placing the primary mirror in its final configuration. During this time, a "momentum flap" will be extended to counteract the radiation pressure from sunlight.

 

On the cool side, a panel that acts as a radiator will extend, allowing the cooling of the instruments to start—one of the instruments will need to be at seven Kelvin to operate. Cooling to operating temperatures is expected to take 96 days.

 

Everything will be in its final configuration by about two weeks after launch. From there, the mirrors have to move a bit more than a centimeter to reach their final position. The motors that manage this also handle the precise control of the mirrors to fine-tune the configuration, so they can only move things very gradually. As a result, traversing that small distance will take the mirrors 10 days.

 

Once that's all complete, the controllers will start imaging isolated stars to make the fine adjustments needed to get the instrument in its operating configuration (though further adjustments to the mirrors can be made later).

 

So, lots of anxious moments to come, but significant hurdles have now been cleared. The Webb is in space, operating under its own power, and communicating with Earth.

COVID-19 patients as young as 12 can now be treated with Paxlovid, an antiviral pill developed by Pfizer, after the Food and Drug Administration issued an emergency use authorization on Wednesday. 

 

“Today’s authorization introduces the first treatment for COVID-19 that is in the form of a pill that is taken orally—a major step forward in the fight against this global pandemic,” said Dr. Patrizia Cavazzoni, director of the FDA’s Center for Drug Evaluation and Research. “This authorization provides a new tool to combat COVID-19 at a crucial time in the pandemic as new variants emerge and promises to make antiviral treatment more accessible to patients who are at high risk for progression to severe COVID-19.” 

 

In early November, Pfizer published trial results for the new oral medication, saying that it reduced hospitalizations and deaths due to COVID-19 by 89 percent. Although the results had not undergone peer-review, Paxlovid's strong effectiveness moved an independent data-monitoring committee to recommend ending the trial early.

 

Paxlovid is the second COVID-19 pill to be developed, with Merck publishing Phase III results for its oral COVID-19 treatment, Molnupiravir, at the beginning of October. While initial results showed a 50 percent reduction in the risk of hospitalization and death from COVID-19, further analysis pegged Molnupiravir as just 30 percent effective. Despite the disappointing results, the FDA approved an emergency use authorization for it in late November by a 13-10 vote.

 

Development on what became Paxlovid began after the SARS outbreak of 2002. It works by hindering an enzyme called a proteasee, which is found in many coronaviruses, including SARS-CoV-2. Inhibiting this enzyme prevents the virus from replicating inside the body.

 

Paxlovid has also been approved by the Committee for Medicinal Products for Human Use of the European Medicines Agency for treating non-severe cases of COVID-19.

 

The newly approved medication will be in short supply for now, as Pfizer says fewer than 200,000 doses will have been made available by the end of the year. With the help of contract manufacturers, an additional 120 million doses should be produced by the end of 2022.

 

The FDA stresses that Paxlovid isn't designed to prevent infection after exposure, and it's not indicated for severe cases requiring hospitalization. In fact, the agency makes it clear that it is "not a substitute" for vaccination. But with omicron raging across the country (and around the world), doctors now have another tool for treating COVID-19.

Expectations for active geology on Pluto were pretty low prior to the arrival of the New Horizons probe. But the photos that came back from the dwarf planet revealed a world of mountains, ridges, and... strange lumpy things that don't have an obvious Earthly analog. One of the more prominent oddities was the plain of Sputnik Planitia, filled with nitrogen ice that was divided into polygonal shapes separated by gullies that were tens of meters deep.

 

Scientists quickly came up with a partial explanation for these structures: convection, where heat differences cause deeper, warmer nitrogen ices to bubble through the soft material toward the surface. The problem is that the planet has no obvious sources of heat deep inside. Now, however, a group of European researchers is suggesting that the convection could be driven by surface cooling, rather than heat from the planet's interior. The secret is the sublimation of nitrogen ices directly into vapors.

Lacking heat

Explaining the formations on small, icy bodies like Pluto is difficult because scientists expect that they lack the heat sources that drive plate tectonics, like those on Earth. These icy bodies are small enough that any heat generated by the collisions that built them, and the dwarf planet, dissipated long ago. And they don't have enough metallic materials for radioisotopes to provide ongoing heat generation. The few exceptions to this, like Europa and Enceladus, are heated by gravitational interactions with the giant planets they orbit, but that's not an option for Pluto, either.

 

As such, it's difficult to come up with a large source of heat that would still be present billions of years after the Solar System's formation. And that's a problem for the idea of convection. Here on Earth, the planet's internal convection is driven by heat escaping from the planet's core. And that convection in turn drives volcanic activity on the surface. Without that sort of heat, it's hard to see how convection can drive the features we're seeing on Pluto.

 

The insight the European team had was that it's not absolute heat that's necessarily needed to drive convection. Rather, it's the temperature difference that matters (along with the ability of the material involved to deform). So, a way of cooling the surface could be just as effective as a way of heating the interior.

 

And there was a clear candidate for that. When warmed by the Sun, a small amount of the nitrogen ice will vaporize into a gas in a process called sublimation. And, in the process, the nitrogen molecules that escape take some of the heat of the ice with them, providing a small amount of cooling. It's not much on a per-atom basis, but Sputnik Planitia is a vast plane of ice, and it has had billions of years to undergo sublimation.

 

Plus, researchers had already explained other features on Pluto that may be produced by sublimation.

A model sublime

Obviously, we can't just head out to Pluto to determine whether nitrogen is sublimating off the surface. So instead, the research team built a convection model and used some physically plausible values for the properties of the nitrogen ice and amount of energy available to it. In other cases, they varied parameters across a range to see what values might result in different behavior.

 

As a first test, they ran their model using sublimation to provide a heat difference to the ice and ran a second version of the model that simply supplied a temperature gradient to the ice. In the latter case, polygons did form, but they looked different from what we see on Pluto. Perhaps most significantly, their high points were near the edges of the polygons, rather than in the center. By contrast, when sublimation was used, things looked very much like Pluto.

 

By testing out different parameters, the team was able to determine that high-viscosity materials end up stalling out as little fresh material finds its way to the surface. For viscosities that are too low, the model ended up failing to form any areas with significant contrast between them, so no boundary regions are apparent.

 

Watching the polygons develop indicates that they gradually emerge from random instabilities in the convection and then gradually reorganize into sheet-like downwellings that form the sides of the polygons. Similarly, small-scale plumes gradually condense into the single large upwelling that forms the central region of the plume.

 

The degree to which this system can operate, however, depends on the details of Pluto's orbit, details that change over periods of millions of years. So it's possible that the features formed and decayed multiple times during the dwarf planet's history.

 

Nature, 2021. DOI: 10.1038/s41586-021-04095-w  (About DOIs).