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• 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.

• 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.

• 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.

• 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.

• 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).

• 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.

• 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.

• 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.

• Forces exerted by a living cell or a microorganism are tiny, often no larger than a few nanonewtons. For comparison, one nanonewton is the weight of one part in a billion of a typical chocolate bar. Yet, for biological cells and microbes, these forces are enough to allow cells to stick to a surface or microbes to propel themselves toward nutrients. Scientists from Finland and Germany now present a highly adaptable technique using micropipette force sensors to precisely measure the forces exerted by a wide range of micron-sized organisms. This novel method has now been published in Nature Protocols.

• The concentration of Total Dissolved Salts, which should ideally be 500 ppm, was found to be as high as 900-3,500 ppm. The electrical conductivity of the water in IDAs was found to be between 1,500-4000 millisiemens per centimeter (mS/cm). According to the Bureau of Indian Standards (BIS), the water in these lakes is not even fit for irrigation, as it falls in the ‘medium’ (750-2,250 mS/cm) and ‘bad’ (2,250-4,000mS/cm) quality category of water for irrigation. High electrical conductivity is a result of the water getting contaminated by salts and heavy metals, that are released in industrial effluents. 

• Although this is the first time the self-fracking process has been observed in live mouse blastocysts, it is not the first time researchers have observed the microlumen coarsening process. The study's authors report that "similar pressurized fluid bubbles that disrupt cell-cell and cell–extracellular matrix interfaces have been observed in vitro as a result of fluid pressure in the extracellular matrix, osmotic perturbations, or directed ionic transport."

• But if Evans does not make the team, it becomes trickier, especially as Salisbury and Skupski are open about the fact they would prefer to play together.

• Over half of homes want HYDROGEN power: How does it work and will it make bills cheaper?

• A casual or fanatic tea drinker might enjoy learning more about the world of tea from this well-designed and informative volume (with drawings from NYT best-selling illustrator Wendy MacNaughton). It gives historical tidbits and fun facts about different types, plus helpful brewing tips and recipes so they can better enjoy the tea-drinking experience.

• The faster you realise this, the better. “My ex was a heavy drinker and I split with him partly due to this,” says Yaz*, 56. “He had the characteristics of an alcoholic: lies, selling valuable items when I went travelling for 18 months. I googled him recently and saw that he had lost his job due to spending £300 each week on alcohol and stealing from his clients. I was not surprised, and saddened, of course, as he suffered a stroke due to this stress. I had a lucky escape.”

• Zero! Boring! Almost as boring as being asked, every time you decline a drink: why? If there’s one person more boring than a drinker, it’s the drinker who asks why you’re not drinking. Actually, there’s someone even more boring: the non-drinker answering that question. I can’t say I’m pregnant, nor that I’ve fallen off a planter box once too often. I have no excuses, other than heart and brain health. By that stage of the explanation, the previously inquisitive drinker has drifted away for a refill.

• Tight, taut severity won’t please the drinker if its grip on the wine never eases, so a partial exploration of the technique seems the wisest course at this stage. That’s what has happened among Chardonnay-makers in Australia over the last decade. Back in 2015, about 65% of Margaret River Chardonnay saw no malo at all; now, many growers are opting for at least some malo, with the attendant benefits for texture and complexity, despite a warming climate.

• Or you could use different fractions or multiples of the mole. Micromole Day falls on October 17, a Monday this year. Kilomole Day falls on Wednesday, October 26. Ask your students to come up with all the other possibilities using as many sub-multiples and multiples of the mole as fall within the month of October. They might learn the lesser known prefixes, such as femto, atto, zepto and yocto! Mind you, Yoctomole Day won’t work because a yoctomole is only 0.602 thing, and you can’t have a fraction of a thing.

• The lower limit of ATP detection was assessed by measurement evaluations of an ATP standard solution. Initial studies demonstrated an ATP calculated limit of detection (LOD) and limit of quantification (LOQ) equal to 1.3 attomole (amol) and 3.9 amol, respectively. Figure 2 shows the linear response between ATP concentration and RLU.

• To overcome this limitation, Walsworth and colleagues combined quantum diamond NMR with a "hyperpolarization" method that boosts the sample's nuclear spin polarization—and hence NMR signal strength—by more than a hundred-fold. The results reported in PRX realize, for the first time, NMR with femtomole molecular sensitivity.