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• The system uses colloid micronewton thrusters, which operate by applying an electric charge to small droplets of liquid and accelerating them through an electric field, to precisely control the position of the spacecraft. Thrusters that work this way had never been successfully operated in space before LISA Pathfinder launched.

• The spacecraft serves as a shield to protect the test masses from external forces. When LISA Pathfinder responds to pressure from sunlight and microscopic dust impacts, the spacecraft automatically compensates by firing tiny bursts from its micronewton thrusters to prevent the test masses from being disturbed.

• Mechanical forces are integral to many biological processes; however, current techniques cannot map the magnitude and direction of piconewton molecular forces. Here, we describe molecular force microscopy, leveraging molecular tension probes and fluorescence polarization microscopy to measure the magnitude and 3D orientation of cellular forces. We mapped the orientation of integrin-based traction forces in mouse fibroblasts and human platelets, revealing alignment between the organization of force-bearing structures and their force orientations.

• Zhang, Y. et al. Platelet integrins exhibit anisotropic mechanosensing and harness piconewton forces to mediate platelet aggregation. Proc. Natl Acad. Sci. USA 115, 325–330 (2018).

• Forces far smaller than a femtonewton can be detected in high-vacuum conditions, where objects aren’t being buffeted by random collisions [1]. In solution, the sensitivity is lower, although methods have been reported for detecting forces as small as 20 fN [2]. Having a method to detect weaker forces in water could, for example, help researchers explore the mechanics of living cells. Lulu Liu and colleagues at Harvard University have now attained a limit about a hundred times smaller than the previous record, measuring sub-femtonewton forces on a microscopic polystyrene bead suspended in water close to a coated glass surface.

• He and his team found that, with a 1 kilogram test mass spinning nearby, they could measure a force on the particle of 30 attonewtons. An attonewton is a billionth of a billionth of a newton. One limitation is that the test mass must be in motion at the right speed to create a gravitational resonance with the magnet, otherwise the force won’t be strong enough to be picked up.

• In a clever tabletop experiment, researchers at Leiden University in the Netherlands, the University of Southampton in the UK, and the Institute for Photonics and Nanotechnologies in Italy measured a force of around 30 attonewtons on a particle with just under half a milligram of mass. An attonewton is a billionth of a billionth of a newton, the standard unit of force.

• The gravitational force on the levitated particle was measured as a brass-weighted electrical bicycle wheel revolved about a meter away, altering the proximity of the weights to the particle. The gravitational force, contingent on the masses and distance between two objects, was observed in the experiment, where a half-milligram particle experienced a 30-attonewton force. An attonewton is one billionth of a billionth of a newton.

• "This bolometer does that accurately and reliably at 1 femtowatt or below. That's a trillion times less power than used in typical power calibrations."

• Ditmire says his near-petawatt laser outruns NIF’s laser, and he even has plans for making it more powerful by using some special laser glass which can amplify the power to 100 kJ, about 500 times more. Building an exawatt laser would take up to 10 years to achieve, with proper governmental and private funding, he says.

• Todd Ditmire, director of the High Intensity Laser Science Group at the University of Texas at Austin, reported at this week’s meeting that a new type of glass should be able to handle the intense pulses of light needed to create an exawatt laser. The glass would be doped and used to create devices called amplifiers–when light from a laser shines on the glass amplifier, ions in the glass absorb the light and re-emit it at higher energy. “The glass is just a host–it’s a transparent material that holds the ions,” says Ditmire.

• A more ambitious goal is to get the energy of the learning pulses to match that of the artificial neuron’s output pulses. Right now, each output voltage spike carries less than one attojoule of energy. But it takes at least 3 attojoules to budge the nanoclusters and cause learning. So, for now, learning has to happen “off-line” because one neuron can’t teach another without assistance. (Even so, once trained, the system would operate faster and with lower energy than any other.)

• Important working principles of a biological synapse have been emulated, such as paired-pulse facilitation (PPF), short-term plasticity (STP), long-term plasticity (LTP), spike-timing dependent plasticity (STDP), and spike-rate dependent plasticity (SRDP). Most amazingly, energy consumption of the device can be reduced to a femtojoule level per synaptic event, which is a value magnitudes lower than previous reports. It rivals that of a biological synapse. In addition, the organic artificial synapse devices not only provide a new research direction in neuromorphic electronics but even open a new era of organic electronics.

• OPTIMA is a 4.5-year three-phase program that will involve several contractors, so additional contracts are expected. In the project's first phase, Georgia Tech seeks to develop a low-energy single-transistor-size multiply compute element with 1 femtojoule per bit energy to data ratio, five-nanosecond read speed, six F2 nominal size, and 1,010 read endurance.

• This new temperature is six times lower than the previous record, and marks the first time that a gas was cooled below 1 nanokelvin (1 billionth of a degree). At absolute zero (-273 deg Celsius or -460 deg Fahrenheit), all motion stops, except for tiny atomic vibrations, since the cooling process has extracted all energy from the particles. By improving cooling methods, scientists have succeeded in getting closer to absolute zero.

• This new temperature is six times lower than the previous record and marks the first time a gas was cooled below one nanokelvin (one billionth of a degree). At absolute zero (-273? Celsius or -460? Fahrenheit), all motion stops, except for tiny atomic vibrations, since the cooling process has extracted all energy from the particles.

• Given that these orbits last approximately 20 days, the passing of gravitational waves in the microhertz frequency range impact them particularly. Blas and Jenkins ascertained that these systems could also be potential detectors of these types of gravitational waves.

• Although scientists have observed ambient seismic noise for more than a century, free oscillations of Earth — vibrations with frequencies of 2 to 7 millihertz that are continuous and persist globally — were not discerned until the aftermath of the magnitude-9.5 earthquake that struck Chile in 1960, when scientists recorded standing waves in the solid earth. At the time, it was thought that Earth’s free oscillations were faint residual tectonic tremors left over from large earthquakes and that the phenomenon was transient.

• Astronomers from Australia and Taiwan report the discovery of millihertz quasi-periodic oscillations in a neutron-star low-mass X-ray binary known as 1RXS J180408.9−342058. The discovery, detailed in a paper published September 3 on the arXiv preprint server, could help astronomers better understand the nature and behavior of X-ray binary sources.

• Similar to LIGO, LISA will detect gravitational waves by bouncing laser light along extended arms, measuring the minuscule variations in arms length. But while LIGO has arms just 4 kilometers long, LISA could have arms millions of kilometers long. Where LIGO can detect powerful transient bursts of gravitational waves with frequencies under a kilohertz, such as the mergers of black holes, LISA will detect millihertz waves and will be able to detect not just black hole mergers, but the gradual inspiraling of supermassive black holes and possibly even the remnant gravitational waves of the big bang.

• The digital distribution of on-demand audio content — commonly known as podcasting — has been growing steadily in recent years. To analyse industry potential in the Caribbean and improve career opportunities for young content creators, the EU-funded UNESCO programme Transcultura: Integrating Cuba, the Caribbean and the European Union through Culture and Creativity organised the online debate ‘Waves between the Caribbean and Europe: Connecting Creative audiences through Podcasts’ on 22 September 2023.

• At the beginning, he wanted to be a megaphone for what he learned at university: he wanted to enable people who were not able to attend to learn the same things he did. His ambitions, however, became more and more political.  With his art, he tries to provide a new form of platform for political discussion: “we need a way to talk about this stuff that isn’t awkward, that isn’t antagonistic. And podcasting is a canvas [for that]”. 

• The Town contracts a professional company to set out traps, collect and test for West Nile Virus (WNV) and should WNV be identified, larvicide and adulticide as necessary. Town staff will be actively looking for areas of mosquito breeding and treating those areas as necessary. Residents and businesses can help the Town by looking for areas mentioned below and eliminating sources and habitats for mosquitoes.

• An aircraft releases aerial application of larvicide and adulticide to keep mosquitoes contained at Craney Island dredged material management area in Portsmouth, Virginia. Hampton Roads consistently ranks high among the nation’s worst regions for mosquito populations, according to the Virginia Mosquito Control Association. (U.S. Army file photo)

• Adult mosquito trapping, surveillance, larvicide and adulticide treatments have been underway throughout the town since June and will continue to the end of the season, which is typically through August.

• To reduce mosquito activity and the risk of West Nile virus, the Health Department will conduct an adulticide treatment in Brooklyn.

• The Florida Keys Mosquito Control District (FKMCD) operation started in earnest with several DC-3 and smaller aircraft dispersing adulticide around Monroe County, which spans hundreds of small islands in addition to the larger inhabited islands making up the Florida Keys. Many of the keys comprise marshland, a prime breeding ground for mosquitos.

• Known for crafting one of the world’s first posture-correcting seats, centering on the concept of “sitting on your ischium bones,” ayur-chair’s products are designed to help relieve lower back tension, as well as improve the sitter’s posture and concentration.

• One issue was that the ischium seems to be a completely new structure in tetrapods and transitional fossils such as the ancient fish Panderichthys. Existing around 380 million years ago, Panderichthys did not have an ischium, despite displaying evolutionary transitional characters in the head and limbs.

• The equine pelvis is composed of three fused bones: ilium, ischium and pubis. The sacrum, the lower part of the equine back, is composed of five fused vertebrae. The sacroiliac joint is located where the sacrum passes under the top of the pelvis (tubera sacrale). The dorsal, ventral and interosseous sacroiliac ligaments help strengthen the SI joint. 

• We examined 60 risk factors for major postoperative complications in PIs over sacrum/coccyx, ischium or trochanter between 01/2016 and 12/2021. We performed descriptive analysis and computed global p-values using likelihood ratio tests adjusted for clustering of PIs in individuals.

• This lager fittingly skanks along smoothly with just a hint of thrilling malice; the malts are just a bit maltier than an actual Mexican beer, and while someone with taste buds blown out by über-IPAs might go “meh,” there’s a bit more hop bite than is typical for the style, too. You know, California taking stuff from elsewhere and goosing it just a bit to make it its own.

• The Bier Library has been consistently brewing Festbier for every Oktoberfest. Cold conditioned for at least 45 days for a clean and crisp taste, Festbier is a malty German lager which clocks in at about 5.8% ABV. It is paler, lighter and much easier to drink and so is the reason why they brew a Festbier instead of a traditional Märzen, which is more maltier and higher on the ABV.

• A'a lava also forms from molten basalt. It is thicker and cooler than pahoehoe when it emerges from a volcano, which means that it travels more slowly, creating rough and lumpy blocks of rock. In this picture, taken at Cape Hammond on the Galapagos Islands, a viscous stream of a'a releases plumes of steam as it enters the sea. (Image: Tui de Roy/minden/NGS)

• They found that under the low atmospheric pressure and low temperatures of the Martian surface, mud flows would end up looking similar to pahoehoe flows on Earth.

• Prayasta 3D Inventions Pvt Ltd supplies rupture-free and suturable 3D breast implants and prostheses. The startup uses its indigenously developed elastomer additive manufacturing (iEAM) technology for these medical implants. They are supported by BIRAC funding provided by the Department of Biotechnology and DST’s Nidhi Prayas.

• The suturable DuraGen matrix is a graft that can be sutured and was designed to repair dural defects in patients who require mechanical anchoring of the graft.

• "To the best of our knowledge, this is first demonstration of a suturable electronic system for biomedical applications and we believe that this will be a large step towards clinical applications of implantable electronic devices," Lee said. "As a next step, the sensing system should be made bioresorbable, to remove the requirement for a second surgery to remove the implanted device after use. Therefore, we are now working on advancing the fiber-based implantable sensor to a fully bioresorbable system."

• The other approach is aimed at filling large openings with methods ranging from building long, underground barrier walls to plugging faults. The idea is to pump down two streams of chemicals that meet at the leak site and build an impermeable barite barrier.

• The discovery of abundant barite at Indy is an exciting and important development, improving the potential for discovery of district-scale Sedex deposits (see Figure 1). Additional barite results are pending and will provide further insight into barite distribution and its link to Sedex mineralization at the 30 km long Project. The Company is also currently renewing its drill permit for a 5-year term.