Today’s huge ships aren’t ready for bridges
Tweeting about your paper doesn’t boost citations: A case study of the use of Mifepristone in the United States
Although it seems to increase engagement, it doesn’t translate into citations. A group of 11 researchers, each with at least several thousand followers, tweeted about a combined 110 articles between late 2018 and early 2020. In the short term, this increased downloads and Altmetric scores, which is a measure of how many people have looked at and are talking about it. The citation rates for the papers were the same as those of the control articles after three years.
Members of the US Supreme Court expressed scepticism yesterday about arguments from a group of anti-abortion organizations and physicians seeking to restrict use of the abortion drug mifepristone in the United States. Over the past eight years, the US Food and Drug Administration expanded the drug’s usage limit from 7 to 10 weeks of pregnancy and allowed it to be sent by post. If the court invalidates those actions, access would be restricted nationwide. The case has no scientific merit because the drug Mifepristone has proved to be safe and effective. A decision is expected in June.
Source: Daily briefing: Tweeting about your paper doesn’t boost citations
The Perseus Plateau: Where did we start? How did we know the ancient world and how did we get our first explorers visas?
After Homo sapiens expanded out of Africa 70,000 years ago, they seem to have paused for some 20,000 years before colonizing Europe and Asia. Now researchers think they know where. Looking at ancient and modern DNA, and the environment of the time, scientists have pinpointed the Persian Plateau — which in this definition encompasses Iran, the United Arab Emirates, Kuwait and parts of Oman — as the perfect place. It may be difficult to confirm this because of the local archaeological evidence. Archeologist Michael Petraglia says there is little work done there because of geopolitics.
Engineers say that the plans for the Francis Scott Key Bridge would have been better if it had survived a collision with a ship. The bridge in Baltimore collapsed when one of its supports was struck by the cargo ship. The shocking speed of the collapse was due in part to its ‘continuous truss’ design, specialists say. The design loads for the concrete piers used to support the structure were exceeded when the container ship crashed into it, causing the entire structure to collapse quickly.
In 1997 Suzanne Simard discovered a network of roots and fungi which was suggested to be an exchange of resources. Simard’s ideas, further expressed in her hit scientific memoir Finding the Mother Tree, resonated deeply with many. But some ecologists think our fascination with the ‘wood wide web’ has outstripped the scientific evidence that underpins it.
There were ten people invited to speak at a panel in Portugal last month, but only four were able to get visas, and none of them had a pet. She wrote that she felt humiliated, embarrassed and insulted by her experience. Her visa fees, flights and other costs were not refundable. Visa issues can affect efforts to prevent further biodiversity loss. “Our participation is not a matter of simply ticking the inclusivity boxes, but a deliberate effort to ensure that the voices of people for whom some of these conservation policies are formulated are heard, and their opinions sought,” writes Owusu-Gyamfi.
Bridges aren’t ready for today’s massive ships: The case of the New Castle, Delaware, whale-catching project and the Panama canal expansion
It’s possible to make bubbles more stable by suspending them in the air. This could reduce the need for surfactants that help them keep from popping when they’re used in industrial processes. Researchers were able to maintain soap stability for up to 15 minutes by using Ultrasonic Waves, which is new to the space station. The bubbles were rotating a few times per second in the way sound waves moved around them. Nature Research Highlight is a 3 min read.
Azizinamini expects the National Transportation Safety Board to take a “very hard look” at the regulations in place to see if there are better ways to protect the nation’s bridges. As an engineer, the first thing you learn is that public safety is the most important issue.
The collapse of the Key Bridge will likely lead some cities to reevaluate the safeguards their bridges have in place. The New Castle, Delaware, project to install dolphins at the Delaware Memorial Bridge was kicked off last year. The city took the initiative to fortify the bridge, but federal agencies could soon make other cities do the same.
Large ships carry their own set of risks. The Ever Given ran aground in the Suez Canal in June of 2021, and was trapped for a week. Modifications were made to accommodate the increased sizes of ships. ThePanama Canal expansion project was completed to help meet the demand for larger vessels. In 2019, the Bayonne Bridge connecting New York and New Jersey was raised 64 feet so ships could fit underneath.
The average size of cargo ships has grown greatly over the past 20 years as shipping companies contend with increased demand for goods. More than 90 percent of traded goods travel by water, and maritime trade volumes are projected to triple by the year 2050 according to the Organisation for Economic Co-operation and Development. The reason shipping companies have started opting for larger “mega-ships” is simple: the larger the ship, the more goods it can carry in a single trip from retailers like Amazon, Target, and Walmart.
The Construction and Behavior of the Key Bridge During the Decay of an Out-of-Control Floating Ship: The Impact of a Four-Span Span
Officials tell The New York Times that the Key Bridge had concrete barriers installed in the river that were “intended to deflect or slow an out-of-control vessel.” However, they’re situated far from the bridge’s support beams, which means they didn’t offer any real protection in case of a direct impact.
New rules typically take a few years to be adopted. It could have been in the mid-2000s before you see a bridge that was designed for it. That is because of the lengthy process we use to build bridges over the water. They are expensive, and can be hard to integrate with the environment.
“The 3-span continuous nature means that when the main span’s pier was destroyed by the ship, the two directly affected spans lost one of their primary supports,” Douglas Schmucker, a professor of civil and environmental engineering at the University of Utah, tells The Verge. When the middle span collapsed, the third span was pulled along with it because it was designed to function together.
