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Jun 23, 2022

There are more galaxies in the Universe than even Carl Sagan ever imagined

Posted by in categories: education, space

The Universe is a vast place, filled with more galaxies than we’ve ever been able to count, even in just the portion we’ve been able to observe. Some 40 years ago, Carl Sagan taught the world that there were hundreds of billions of stars in the Milky Way alone, and perhaps as many as 100 billion galaxies within the observable Universe. Although he never said it in his famous television series, Cosmos, the phrase “billions and billions” has become synonymous with his name, and also with the number of stars we think of as being inherent to each galaxy, as well as the number of galaxies contained within the visible Universe.

But when it comes to the number of galaxies that are actually out there, we’ve learned a number of important facts that have led us to revise that number upwards, and not just by a little bit. Our most detailed observations of the distant Universe, from the Hubble eXtreme Deep Field, gave us an estimate of 170 billion galaxies. A theoretical calculation from a few years ago — the first to account for galaxies too small, faint, and distant to be seen — put the estimate far higher: at 2 trillion. But even that estimate is too low. There ought to be at least 6 trillion, and perhaps more like 20 trillion, galaxies, if we’re ever able to count them all. Here’s how we got there.

Jun 23, 2022

Interstellar Travel Could Be Possible Even Without Spaceships, Scientist Says

Posted by in categories: existential risks, space travel

In about 5 billion years, the Sun will leave the main sequence and become a red giant. It’ll expand and transform into a glowering, malevolent ball and consume and destroy Mercury, Venus, Earth, and probably Mars.

Can humanity survive the Sun’s red giant phase? Extraterrestrial Civilizations (ETCs) may have already faced this existential threat.

Could they have survived it by migrating to another star system without the use of spaceships?

Continue reading “Interstellar Travel Could Be Possible Even Without Spaceships, Scientist Says” »

Jun 23, 2022

Beyond longevity: The DIY quest to cheat death and stop aging

Posted by in categories: biotech/medical, life extension, neuroscience

At 79, he’s already outlived the CDC’s official life expectancy by two years and he has no intention of dying — or even slowing down — anytime soon. An active man, Scott jets between his homes in upstate New York and Florida, flies to exotic locations such as Panama City for business and still finds time for the odd cruise. His secret? A DIY regime of self-experimentation and untested therapies he believes will keep him going well past the next century.

Self-experimenters litter the history of medical science. Dentist Horace Wells dosed himself with nitrous oxide in 1,844 to see if it could kill pain, Nicholas Senn inflated his innards with hydrogen a few decades later to work out if it could diagnose a ruptured bowel, and more recently, Barry Marshall drank a solution containing H. pylori in 1985 to prove the bacterium caused ulcers.

These scientists risked their own health to make a medical breakthrough or prove a theory, but Scott is not a scientist. He’s an amateur enthusiast, also known as a biohacker. Biohackers engage in DIY biology, experimenting on themselves to enhance their brain and body. And many of them — like Scott — see longevity as the ultimate prize.

Jun 23, 2022

Discrete Wavelet Transform Analysis of the Electroretinogram in Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder

Posted by in category: neuroscience

Background: To evaluate the electroretinogram waveform in autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) using a discrete wavelet transform (DWT) approach.

Methods: A total of 55 ASD, 15 ADHD and 156 control individuals took part in this study. Full field light-adapted electroretinograms (ERGs) were recorded using a Troland protocol, accounting for pupil size, with five flash strengths ranging from −0.12 to 1.20 log photopic cd.s.m–2. A DWT analysis was performed using the Haar wavelet on the waveforms to examine the energy within the time windows of the a-and b-waves and the oscillatory potentials (OPs) which yielded six DWT coefficients related to these parameters. The central frequency bands were from 20–160 Hz relating to the a-wave, b-wave and OPs represented by the coefficients: a20, a40, b20, b40, op80, and op160, respectively. In addition, the b-wave amplitude and percentage energy contribution of the OPs (%OPs) in the total ERG broadband energy was evaluated.

Results: There were significant group differences (p < 0.001) in the coefficients corresponding to energies in the b-wave (b20, b40) and OPs (op80 and op160) as well as the b-wave amplitude. Notable differences between the ADHD and control groups were found in the b20 and b40 coefficients. In contrast, the greatest differences between the ASD and control group were found in the op80 and op160 coefficients. The b-wave amplitude showed both ASD and ADHD significant group differences from the control participants, for flash strengths greater than 0.4 log photopic cd.s.m–2 (p < 0.001).

Jun 23, 2022

Neocortex saves energy

Posted by in categories: food, neuroscience

Despite constituting less than 2% of the body’s mass, the human brain consumes approximately 20% of total caloric intake, with 50% of the energy being used by cortex (Herculano-Houzel, 2011). The majority of this energy is spent by neurons to reverse the ion fluxes associated with electrical signaling via Na+/K+ ATPase (Attwell and Laughlin, 2001; Harris et al., 2012). Excitatory synaptic currents and action potentials are particularly costly in this regard, accounting for approximately 57% and 23% of the energy budget for electrical signaling in gray matter, respectively (Harris et al., 2012; Sengupta et al., 2010). Given this cost, and the scarcity of resources, the brain is thought to have evolved an energy-efficient coding strategy that maximizes information transmission per unit energy (i.e., ATP) (Barlow, 2012; Levy and Baxter, 1996). This strategy accounts for a number of cellular features, including the low mean firing rate of neurons and the high failure rate of synaptic transmission, as well as higher order features, such as the structure of neuronal receptive fields (Albert et al., 2008; Attwell and Laughlin, 2001; Harris et al., 2015; Levy and Baxter, 1996; Olshausen and Field, 1997; Sterling and Laughlin, 2015). Scarcity of food, therefore, appears to have strongly sculpted information coding in the brain throughout evolution.

Energy intake is not fixed but can vary substantially across individuals, environments, and time (Hladik, 1988; Knott, 1998). Given that the brain is energy limited, one hypothesis is that in times of food scarcity, neuronal networks should save energy by reducing information processing. There is some evidence to suggest that this is the case in invertebrates (Kauffman et al., 2010; Longden et al., 2014; Plaçais et al., 2017; Placais and Preat, 2013). In Drosophila 0, food deprivation inactivates neural pathways required for long-term memory to preserve energy (Plaçais et al., 2017; Placais and Preat, 2013). Experimental re-activation of these pathways restores memory formation but significantly reduces survival rates (Placais and Preat, 2013). Similar memory impairments are seen with reduced food intake in C. elegans (Kauffman et al., 2010). Moreover, in blowfly, food deprivation reduces visual interneuron responses during locomotion, consistent with energy savings (Longden et al., 2014). However, it remains unclear whether and how the mammalian brain, and cortical networks in particular, regulate information processing and energy use in times of food scarcity.

Here we used the mouse primary visual cortex (V1) as a model system to examine how food restriction affects information coding and energy consumption in cortical networks. We assessed neuronal activity and ATP consumption using whole-cell patch-clamp recordings and two-photon imaging of V1 layer 2/3 excitatory neurons in awake, male mice. We found that food restriction, resulting in a 15% reduction of body weight, led to a 29% reduction in ATP expenditure associated with excitatory postsynaptic currents, which was mediated by a decrease in single-channel AMPA receptor (AMPAR) conductance. Reductions in AMPAR current were compensated by an increase in input resistance and a depolarization of the resting membrane potential, which preserved neuronal excitability; neurons were therefore able to generate a comparable rate of spiking as controls, while spending less ATP on the underlying excitatory currents. This energy-saving strategy, however, had a cost to coding precision. Indeed, we found that an increase in input resistance and depolarization of the resting membrane potential also increased the subthreshold variability of visual responses, which increased the probability for small depolarizations to cross spike threshold, leading to a broadening of orientation tuning by 32%. Broadened tuning was associated with reduced coding precision of natural scenes and behavioral impairment in fine visual discrimination. We found that these deficits in visual coding under food restriction correlated with reduced circulating levels of leptin, a hormone secreted by adipocytes in proportion to fat mass (Baile et al., 2000), and were restored by exogenous leptin supplementation. Our findings reveal key metabolic state-dependent mechanisms by which the mammalian cortex regulates coding precision to preserve energy in times of food scarcity.

Jun 23, 2022

A Huge Step Forward in Quantum Computing Was Just Announced: The First-Ever Quantum Circuit

Posted by in categories: computing, quantum physics

Australian scientists have created the world’s first-ever quantum computer circuit – one that contains all the essential components found on a classical computer chip but at the quantum scale.

The landmark discovery, published in Nature today, was nine years in the making.

“This is the most exciting discovery of my career,” senior author and quantum physicist Michelle Simmons, founder of Silicon Quantum Computing and director of the Center of Excellence for Quantum Computation and Communication Technology at UNSW told ScienceAlert.

Continue reading “A Huge Step Forward in Quantum Computing Was Just Announced: The First-Ever Quantum Circuit” »

Jun 23, 2022

RIP expensive silicon chips the future

Posted by in categories: computing, innovation

Or at least, they will be in the coming decades.


Cheap, plastic processors are the key to creating a whole new world of flexible tech, and luckily, there’s been a developmental breakthrough.

Jun 23, 2022

Understanding and Reframing the Fear of Rejection

Posted by in category: futurism

Summary: At some point, we all face social rejection. Researchers say that while rejection affects us all differently, it’s how respond to the setback that determines how rejection affects us.

Source: university of new south wales.

If there’s one thing for sure, it’s that life doesn’t always go our way. A rejection, no matter the circumstance or size, can be painful, but it is something we all experience at some stage in our lives.

Jun 23, 2022

Biochemistry Researchers Repair and Regenerate Heart Muscle Cells

Posted by in categories: biotech/medical, chemistry, life extension, mathematics

Researchers at the University of Houston are reporting a first-of-its-kind technology that not only repairs heart muscle cells in mice but also regenerates them following a heart attack, or myocardial infarction as its medically known.

Published in The Journal of Cardiovascular Aging 0, the groundbreaking finding has the potential to become a powerful clinical strategy for treating heart disease in humans, according to Robert Schwartz, Hugh Roy and Lillie Cranz Cullen Distinguished Professor of biology and biochemistry at the UH College of Natural Sciences and Mathematics.

The new technology developed by the team of researchers uses synthetic messenger ribonucleic acid (mRNA) to deliver mutated transcription factors — proteins that control the conversion of DNA into RNA — to mouse hearts.

Continue reading “Biochemistry Researchers Repair and Regenerate Heart Muscle Cells” »

Jun 23, 2022

The Startup at the End of the Age : Creating True AI and instigating the Technological Singularity

Posted by in categories: augmented reality, biotech/medical, information science, mathematics, mobile phones, robotics/AI, singularity, supercomputing, virtual reality

The talk is provided on a Free/Donation basis. If you would like to support my work then you can paypal me at this link:
https://paypal.me/wai69
Or to support me longer term Patreon me at: https://www.patreon.com/waihtsang.

Unfortunately my internet link went down in the second Q&A session at the end and the recording cut off. Shame, loads of great information came out about FPGA/ASIC implementations, AI for the VR/AR, C/C++ and a whole load of other riveting and most interesting techie stuff. But thankfully the main part of the talk was recorded.

Continue reading “The Startup at the End of the Age : Creating True AI and instigating the Technological Singularity” »

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