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Though many negative repercussions of human immunodeficiency virus infection can be mitigated with the use of antiretroviral therapy (ART), one area where medical advances haven’t made as much progress is in the reduction of cognitive impacts. Half of HIV patients have HIV-associated neurocognitive disorders (HAND), which can manifest in a variety of ways, from forgetfulness and confusion to behavior changes and motor deficiencies.

To better understand the mechanisms underlying HAND, researchers from Penn’s School of Dental Medicine and Perelman School of Medicine and from the Children’s Hospital of Philadelphia (CHOP) brought together their complementary expertise to create a laboratory model system using three of the types of brain cells thought to be involved. Led by doctoral student Sean Ryan, who was co-mentored by Kelly Jordan-Sciutto of Penn Dental Medicine and Stewart Anderson of CHOP and Penn Medicine, the model recapitulates important features of how HIV infection and ART affect the brain.

“Frankly the models we generally use in the HIV field have a lot of weaknesses,” says Jordan-Sciutto, co-corresponding author on the paper, which appears in the journal Stem Cell Reports. “The power of this system is it allows us to look at the interaction between different cell types of human origin in a way that is more relevant to patients than other models.”

Didymos, a 2,650-foot-wide asteroid, has an atypical cosmic companion— a 535 foot-wide satellite named Didymoon (10). These new two celestial bodies are not making a dangerous rendezvous with Earth, but they do provide an interesting opportunity for an apocalyptic dress rehearsal. NASA and ESA’s Double Asteroid Redirection Test (DART) will head to Didymos, to knock Didymoon off course. Along with its six picture-snapping Italian Space Agency cubesats, the mission will also send a follow-up ESA spacecraft named Hera to definitively answer if we can manipulate the trajectory of Earth-bound asteroids.

Planetary defense researchers at Lawrence Livermore National Laboratory (LLNL) continue to validate their ability to accurately simulate how they might deflect an Earth-bound asteroid in a study that will be published in the April issue of the American Geophysical Union journal Earth and Space Science.

The study, led by LLNL physicist Tané Remington, also identified sensitivities in the code parameters that can help researchers working to design a modeling plan for the Double Asteroid Redirection Test (DART) mission in 2021, which will be the first-ever kinetic impact deflection demonstration on a near-Earth asteroid.

Asteroids have the potential to impact Earth and cause damage at the local to global scale. Humankind is capable of deflecting or disrupting a potentially hazardous object. However, due to the limited ability to perform experiments directly on asteroids, understanding how multiple variables might affect a kinetic deflection attempt relies upon large-scale hydrodynamic simulations thoroughly vetted against relevant laboratory‐scale experiments.