Inside the rooftop arena
Sunday, July 12, 2026
First 3D Structure of Inactivated Cone Opsins Revealed in three different studies
Amazing stuff! I limit myself here to one of the three papers.
"... In a new study, ... two researchers ... have succeeded for the first time in determining the three-dimensional structure of human cone opsins in their dark state and showing how their molecular architecture enables their rapid activation by light. This provides important new insights into human vision and its evolution and may offer new starting points for the study of eye diseases that currently lack effective treatment. ..."
From the editor's summary and abstract:
"Editor’s summary
Human daytime vision relies on a trio of visual receptors called opsins, which are found in the cone cells in and around the central region of the retina.
The three opsins are tuned to long, medium, or short wavelengths of light, roughly corresponding to red, green, and blue, and mutations or other defects in cone cell function can lead to vision deficits.
Although the cell biology and biochemistry of color vision have been well studied, up to now, the molecular explanation for cone opsin spectral tuning and signaling kinetics has been limited by a lack of experimental structures.
Three papers in this issue now resolve this deficit.
Schmidt et al. determined structures of the dark state of the green and blue human cone opsins, which revealed important details of these receptors and provide a basis for a femtosecond-resolution spectroscopy study.
Ohashi et al. performed complementary structural, spectroscopic, and computational results with dark-state red and green cone opsins from macaques, which have color vision similar to humans.
Finally, Peng et al. studied all three human cone opsins in the presumed active state bound to a G protein and all-trans retinal.
The three papers together provide a clear picture of the features of these visual receptors that lead to different spectral properties, activation and inactivation kinetics, and recycling. ...
Structured Abstract
INTRODUCTION
High-acuity daylight vision relies on cone photoreceptors, specialized class A G protein–coupled receptors (GPCRs). Like other light-sensitive GPCRs, the three human cone opsins covalently bind vitamin A derivative 11-cis-retinal through a protonated Schiff base. Despite sharing the same chromophore, they detect distinct wavelengths of light and generate swift signaling responses at high repetition rates. Although cone opsins are central to human vision, and in contrast to the well-studied rod photoreceptor rhodopsin, the detailed molecular basis of these functional specializations remains elusive.
RATIONALE
To obtain structure-function relationships that extend the kinetic and mechanistic understanding of photopic vision, we solved cryo–electron microscopy (cryo-EM) structures of the two most evolutionarily and functionally divergent human cone opsins, short-wavelength-sensitive OPN1SW and medium-wavelength-sensitive OPN1MW, in their initial 11-cis-coupled state. We combined the structural data with multiple functional assays, hybrid quantum mechanics/molecular mechanics simulations, time-resolved spectroscopy, and multitaxon opsin sequence analysis.
RESULTS
Cryo-EM structures of cone opsins revealed receptor-specific activation mechanisms and distinct strategies for stabilizing the retinal Schiff base.
OPN1SW, representing the phylogenetically older vertebrate opsins, has a more constrained polar chromophore environment, which contributes to its blue-shifted maximum absorption wavelength (λmax), yet its stabilization is weaker than that of rhodopsin. The architecture of OPN1SW shows substantial divergences in the canonical GPCR microswitch networks, including the replacement of the toggle switch with Y6.48, a disrupted PIF triad, and the absence of a highly conserved sodium- or water-coordination site.
Collectively, these alterations favor a preactive conformation, also captured by cryo-EM. OPN1SW further uses W185ECL2 as a steric switch to transmit the retinal isomerization event across several helices through an extended aromatic network.
In contrast, OPN1MW contains a chloride ion within the chromophore-binding pocket that modulates wavelength sensitivity and influences the amplitude of G protein signaling. This chloride-binding site coevolved with a structural pathway on helix 2 that couples chromophore chemistry to canonical GPCR microswitches.
Both receptors have accessible binding pockets that allow rapid ligand hydrolysis and, consequently, fast retinal turnover.
Femtosecond transient-absorption spectroscopy resolved the photoisomerization cascade, supporting a model in which deprotonation and subsequent hydrolysis limit signal duration in cone opsins.
CONCLUSION
Our structural and mechanistic insights describe how distinctive chromophore environments and GPCR microswitch adaptations tune spectral sensitivity and signaling-state lifetimes in cone opsins. Conservation of central residues across short-wavelength-sensitive and medium-to-long-wavelength-sensitive opsins suggests shared mechanistic principles that shaped the evolution of daylight vision. Similar motifs in other GPCRs, including sensory receptors, inform the strategies for modulating receptor activation kinetics and signal duration."
New insights into human vision (original news release)
Experiment performed at ELI Enables New Insights into Human Vision (original news release) "The retina of the human eye contains six to seven million cone cells. These cells contain light-sensitive proteins known as cone opsins. They enable us to perceive our surroundings in detail in daylight. In a new study, researchers ... have now, for the first time, determined the three-dimensional molecular structure of human cone opsins in their dark state, that is, before they are activated by light."
Illuminating the molecular basis of human daylight vision (no public access)
Cone opsins use distinct chromophore-stabilization strategies to tune spectral sensitivity, activation kinetics, and retinal regeneration.
Germany experienced a net loss or exodus of 400 millionaires in 2025
More bad news for the banana republic of Germany!
Unfortunately, I was not able to find similar data for previous years for Germany from the website of Henley & Partners!
"Germany experienced a net loss of 400 millionaires in the most recent annual tracking. While the country remains home to about 1.78 million high-net-worth individuals" (Google)
"... Germany has the third highest number of people with liquid assets totaling at least $1 million, according to a study. ..."
Germany news: Number of millionaires is growing, study shows "Around 1.78 million people in Germany were classified as high-net-worth individuals or people who have at least $1 million in liquid assets. DW has the latest."
DiPOD: Diffusion Policy Optimization without Drifting Apart
This could be an interesting new paper by Pieter Abbeel and his team!
From the abstract:
"RL post-training has become increasingly pivotal for improving diffusion policies, but existing diffusion policy-gradient methods are often unstable and cannot achieve reliable policy improvement.
We identify the cause as the double-drift phenomenon: optimizing a variational surrogate can let the ELBO separate from the true log-likelihood, which then makes the resulting proxy policy gradient misaligned with the true policy gradient of expected return.
We propose DiPOD, a diffusion policy optimization framework that maintains tight-bound behavior throughout training by interleaving self-distillation with policy-improving gradient updates.
This leads to a simple and practical algorithm: augmenting each diffusion policy-gradient update with an on-policy ELBO regularizer.
Across diffusion language model post-training and continuous-control diffusion policies, DiPOD substantially stabilizes training and reaches higher rewards than previous methods."
Pyrrhus Aeronautics unveils rifle mounted drone control system. Really!
Things around drones are getting very creative! 😊
Though the company name conjures up a Pyrrhic victory! 😊
When will the regional Arab Gulf allies of the US buckle under the attacks by Iran?
Iran pursues a very clever strategy in response to the attacks by the US, retaliate against the Arab allies in the region.
Or will the attacked Arab allies (Saudi Arabia, Kuwait, Bachrain, Qatar) themselves finally resort to stronger military responses against Iran?
Seems to me this could be a matter of time and may happen sooner than later!
P.S. Where are the coward Europeans failing to help the US (e.g. with mine sweepers and escorting ships through the Strait of Hormuz etc.)?
Renewable advocates pin hopes on batteries to fix intermittency, but costs are prohibitive: report
How many batteries would have to be built? How much mining would be necessary? How much CO2 will be emitted?
The subject of how to store the energy generated by so called renewable energy sources is often omitted or deliberately avoided!
"... Researchers with the National Center for Energy Analytics set out to find out if it’s possible to power the grid with wind, solar and batteries. Their report, which was released Thursday, casts considerable doubt on renewable energy proponents’ promise that batteries can resolve the problems of intermittency with wind and solar. ...
“This study demonstrates that a wind-solar-battery policy to meet electricity demand is physically implausible, cost-prohibitive, and unjustifiable on the basis of goals to reduce CO2 emissions,” the report concludes. ..."
"... While the quantity of battery storage has grown rapidly, it remains a minuscule share of total U.S. electricity consumption. At the beginning of 2026, total grid-scale battery storage could supply about 15 minutes of average U.S. electricity demand. ...
This study evaluated the physical and economic feasibility of building a reliable electric system primarily powered by wind, solar, and battery storage. The analysis used a model of the PJM Interconnection system, the nation’s largest grid operator, which covers 13 states and the District of Columbia and serves more than 67 million people.
Using PJM’s long-term forecast through 2045, the study estimated the quantities of wind, solar, and storage batteries that would be needed under three scenarios: renewables only (RO), which consisted of wind, solar, batteries, and existing nuclear plants while retiring all coal and natural gas generation;
natural gas and nuclear (NGN), which comprised existing and new natural gas generators along with new nuclear plants; and
NGN+B, which added battery storage to replace gas-fired generators during peak demand periods.
The analysis showed that to compensate for the intermittency of solar and wind, roughly tenfold more total generating capacity would be required by 2045 under the RO scenario than the NGN scenario. The additional capacity would be needed not only to serve daily or seasonal variations in supply and demand but also to accommodate well-documented wind and solar droughts—that is, multiday periods with little to no sunshine or wind. ..."
Batteries and the Grid: Hype, Hope, and Economic Reality "A PJM-based analysis finds a wind-solar-battery grid is physically implausible and cost-prohibitive—costing ratepayers over $4 trillion, roughly six times a natural gas and nuclear system."
To Retain or to Adapt? Generalizing Continual Learning
This could be an interesting new paper by Doina Precup and Razvan Pascanu and their team!
From the abstract:
"The Continual Learning (CL) literature has long been driven by the goal of mitigating catastrophic forgetting. This objective rests on a pervasive, often unstated assumption: that a lifelong learner should approximate the Joint-Task Learning (JTL) solution and retain all previously acquired knowledge.
We challenge this retention-centered premise, arguing that in non-stationary environments prioritizing retention can impede real-time adaptation.
Shifting the focus to the Average Lifelong Error (ALE), we formalize CL as an online optimization problem governed by the interaction between environmental and learning dynamics.
We introduce Transfer Efficiency as a quantitative measure of the tension between Instability, the bias inherited from conflicting past experience, and Transient Error, the optimization cost of learning new tasks from scratch.
Under mild convergence conditions, holding across linear and neural network models, this decomposition yields a Critical Task Duration: a closed-form threshold beyond which historical knowledge transitions from a warm-start advantage to an optimization liability whenever retention induces a positive stationary bias.
We validate these theoretical predictions on continual image classification and reinforcement learning benchmarks.
Finally, by connecting continual learning to the online learning framework of predictable sequences, we show that JTL is only one instance of a broader family of objectives, and we propose a new general class of continual learning algorithms, which we call Predictive Continual Learning.
Predictive CL algorithms optimize expected future performance under an explicit, dynamically updated model of future tasks.
As a proof of concept, we analyze a Window algorithm that interpolates between JTL and Independent-Task Learning (ITL), outperforming both under controlled distributional drift."
Engineered in One Plant, Three Kingdoms, Five natural psychedelics
Good news!
"... Researchers ... have now managed to bring together in a single organism five psychedelic substances that in nature are scattered across the tree of life.
After uncovering how plants naturally produce one of the best-known psychedelic compounds, DMT, they were able to reengineer that process step by step inside a model plant – along with four other psychedelics. The result is what amounts to a biological factory that could, in the future, be used to simultaneously produce multiple psychedelic molecules, including some that do not naturally occur in plants. ..."
From the abstract:
"Psychedelic indolethylamines with therapeutic potential are naturally produced in plants, fungi, and animals.
Here, we elucidated the complete N,N-dimethyltryptamine (DMT) biosynthetic pathway in hallucinogenic plant species traditionally used in shamanic rituals for spiritual healing.
Leveraging the similarities in their chemical structures, we reconstructed in one plant assay the full biosynthetic pathways of five renowned natural psychedelics; psilocin and psilocybin found in mushrooms, DMT from plants, and bufotenin and 5-methoxy-DMT secreted by the Sonoran Desert toad.
We further engineered halogenated analogs of these molecules, which do not naturally occur in plants and exhibit prospective therapeutic potential for psychiatric conditions.
Blending catalytic functions across the tree of life, coupled with metabolic engineering guided by rational protein design of mutant enzymes, enabled substantially more efficient in planta production of the indolethylamine components.
This work establishes a versatile platform for concurrent biosynthesis and diversification of psychoactive indolethylamines, paving the way for their production in plants."
Fig. 3. Reconstruction of the N,N-dimethyl-tryptamine biosynthetic pathway.
Fig. 5. Metabolic engineering strategy for complete reconstruction of psychedelic indolethylamine biosynthetic pathways in N. benthamiana.
Covid-19 Pandemic recreated in Fast Forward in a test tube
Good news! However, how the SARS-CoV-1 virus was released from the Institute of Virology in Wuhan (a dual use research institute at the time), China will not be answered, I suspect.
"A key step in the origin of many pandemics occurs when an animal-borne virus infects humans and then evolves to spread more efficiently from person to person. That is why scientists and physicians keep a close watch on viruses that could jump from animals to humans, such as emerging strains of avian flu and bat coronaviruses, as well as viruses that have already crossed into humans but, for now, spread poorly among people, such as hantavirus and Ebola.
Researchers have now recreated in a test tube, within just a few months, the evolutionary path the coronavirus followed during the COVID-19 pandemic – from the original Wuhan strain to the emergence of the highly contagious Omicron variants. ..."
From the abstract:
"In vitro protein evolution can provide powerful insights into the amino acid sequences that underlie key biological functions.
Here, we use this to explore the evolutionary trajectories of the SARS-CoV-2 spike protein receptor-binding motif (RBM) binding the human angiotensin-converting enzyme 2 (ACE2), an essential first step in viral infection.
Applying stringent selection pressures starting from the Wuhan or another non-Omicron variant protein-coding sequence results in rapid convergence towards Omicron characteristic mutations and its sub-lineages.
Conversely, under mild selection, only some Omicron-like mutations are selected, however at lower frequencies and with incomplete representation.
Stringent selection results in fewer, but dominant, non-synonymous mutations mirroring Omicron mutations and their variations within its sub-lineages.
Notably, initiating evolution from Omicron itself results in maintenance of Omicron-defining mutations under both conditions.
This evolutionary pattern parallels global SARS-CoV-2 mutation trends as well as in silico simulations, emphasizing the critical role of receptor-binding constraints in shaping viral adaptation.
Mutations primarily associated with immune evasion are not selected by in vitro evolution.
Our findings demonstrate the predictive capacity of in vitro evolution, suggesting Omicron RBM to be the humanized binding motif, emerging from high-stringency selection, superimposed on milder background pressures."
Stringent selection drives convergence toward omicron-like SARS-CoV-2 receptor-binding motifs (open access)
Fig. 1: High-throughput yeast display evolution of SARS-CoV-2 RBD under defined selection pressures.
Fig. 3: Mutation accumulation following in vitro evolution in comparison to SARS-CoV-2.
Geometric Causal Models
This could be an interesting, new paper by David M. Blei and his team!
From the abstract:
"Scientists often seek to draw causal inferences from structured data that is not independently and identically distributed, such as spatial data, network data, or molecular data.
We develop geometric causal models (GCMs), a framework for causal inference from dependent data that exploits underlying symmetries of the data generating process.
For example, in spatial data, we consider processes that are symmetric under translations, or in graph data, symmetric under permutations of the nodes.
We show how symmetries, formalized with group theory, can enable causal identification and estimation.
We deploy ergodic theory for amenable groups to establish identification, and combine geometric deep learning with scalable Bayesian inference for estimation. We recover i.i.d. causal models and do-calculus when the data is a sequence and the symmetry is permutation equivariance, and find novel types of causal models when we use alternate structures and symmetries.
As an example, we construct a causal model that satisfies the symmetries of DNA. This GCM enables new estimators for the effects of genetic variation, combining deep functional genomics models to describe outcomes and DNA language models to describe propensities. We illustrate on semisynthetic data."
“Social Media Addiction” Is Way More Complicated Than You Think
Do not many teenagers go through some temporary infatuation or mania at some point during their adolescence? Oh, yea! Usually, they are harmless and end well!
Who is most responsible to make sure this does not become pathological, addictive etc.? Parents, guardians, older siblings!
"The era of social media addiction litigation is upon us.
In a case heard this March, a Los Angeles jury decided against Meta (the parent company of Instagram) and Google (the parent company of YouTube), finding them liable for negligence and defective design.
The plaintiff was 20-year-old Kaley G. M., who claimed that her decade-long addiction to social media caused her to suffer anxiety, depression, suicidal thoughts, and body dysmorphia. In her complaint, Kaley said she developed a “dangerous dependency” on the platforms. ...
For the defense, the Meta team argued the plaintiff’s psychological distress predated her use of Instagram ...
Kaley won $3 million in compensatory damages, and $3 million in punitive damages. Meta is appealing. ...
The same basic arguments used in Kaley’s lawsuit are driving lawsuits against Meta, Google, Snapchat, and ByteDance (owner of TikTok), filed by over 2,500 individuals, states, and schools. One study suggests that the compensation sought by more than 1,200 school districts totals nearly $500 billion.
Meanwhile, the California court system has coordinated a large group of plaintiffs—representing more than 1,000 cases from across the nation—suing social media companies under a collective known as Judicial Council Coordination Proceeding. The earliest cases will soon come before a California judge. ..."
Saturday, July 11, 2026
Lords of the flies: Thailand's edible insect innovators
Nice headline! Sounds so delicious! Bon appetit! Just kidding!
Protein meal made from black soldier fly larvae is inspected during quality control ...
Logic and language is separated in the brain
Amazing stuff!
"... In research ... researchers ... have shown that people can perform well on tasks that require logical reasoning even if their language abilities are severely impaired. What’s more, brain imaging shows that language-processing parts of the brain are not called on for logical reasoning. ..."
From the significance and abstract:
"Significance
Which cognitive mechanisms allow humans to reason logically, to understand whether a conclusion follows from the premises? Are they the same ones that allow the assembly of words into structured representations?
Scholars have debated for millennia whether logical reasoning is inextricably tied to natural language, or instead relies on a distinct “language of thought” (LOT).
Using fMRI in healthy adults and evaluating logical ability in individuals with severe aphasia, we find that distinct neural systems support language processing vs. logical (inductive and deductive) reasoning. These results suggest that, at least in mature brains, language processing does not underpin logical inference, perhaps due to the distinct representational format of the logical LOT.
Abstract
Humans are endowed with a powerful capacity for inductive and deductive logical thought: we easily form generalizations based on a few examples and draw conclusions from known premises.
Humans also arguably have the most sophisticated communication system in the animal kingdom: natural language allows us to express complex and structured meanings.
Some have therefore argued for a tight relationship between complex thought and language, postulating that reasoning, including logical reasoning, relies on linguistic representations.
We systematically investigated the relationship between logical reasoning and language using two complementary approaches.
First, we used noninvasive brain imaging (fMRI) to examine neural activity as healthy adults engaged in logical reasoning tasks.
And second, we behaviorally evaluated logical abilities in individuals with extensive lesions to the language brain areas and consequent severe linguistic impairment.
Our findings reveal that the language brain network is not engaged during logical reasoning, and patients with severe aphasia exhibit intact performance on logic tasks.
Instead, inductive reasoning recruits the domain-general multiple demand network implicated broadly in goal-directed behaviors,
whereas deductive reasoning draws on brain regions that are distinct from both the language and the multiple demand networks.
Together, these results indicate that linguistic representations are neither utilized nor required for inductive or deductive logical reasoning."
Evidence from formal logical reasoning reveals that the language of thought is not natural language (no public access)
Evidence from Formal Logical Reasoning Reveals that the Language of Thought is not Natural Language (preprint, open access)
A functional brain scan of a neurotypical participant in a new study shows a distinct separation between logic (green) and language (red/yellow) activations.
From Musk to Truth Social: Critics say the 46th President's SEC targeted Trump's allies
The 46th President was a lousy one! May he rest in hell and may the Dimocratic Party be damned for a long time for allowing this to happen!
"On January 14, 2025, just six days before President Donald Trump was sworn in for his second, non-consecutive term, the Securities and Exchange Commission (SEC) filed a lawsuit against billionaire Elon Musk, who was entering the administration with Trump as head of the Department of Government Efficiency (DOGE). ...
After the purchase [of Twitter in 2022], Musk’s other companies, SpaceX and Tesla, were also investigated by the Department of Justice and Federal Trade Commission. Musk himself warned this would happen after he announced he would no longer vote Democrat. ...
Trump himself has faced the SEC recently – also under the [46th President] administration – when his Truth Social media platform began a merger with Digital World Acquisition Corp. (DWAC). When the merger was announced, the SEC began investigating, and a federal grand jury in New York issued subpoenas for DWAC’s board of directors, arguably causing the company’s stock price to drop. The merger was slow-walked, alleges Truth Social. ..."
Venezuela reforms its socialist oil policies, and production soars with Trump’s help
Good news!
"The South American country appeared to take another big step in that effort this week when acting President Delcy Rodriguez signed regulations reforming Venezuela's main oil law.
Under the new regulations, the country’s national oil company, Petróleos de Venezuela SA (PDVSA), effectively loses control of Venezuela’s vast oil resources.
Under the former communist regime, the country’s oil industry floundered. In May 2021, Venezuela was producing less than 600,000 barrels of oil a day, despite having the world’s largest oil reserves. This past May, it was producing nearly 1.2 million barrels of oil per day.
Venezuela nationalized its oil industry in the 1970s. Then in 2007, former President Hugo Chávez forced foreign oil companies to surrender majority stakes to the state, which resulted in the departure of ExxonMobil and ConocoPhillips. Of the big players, only Chevron acquiesced to the communist leader’s demands. ..."
Researcher proposes a way to detect nuclear weapons in space
Good news! However, this proposed detection system seems to be very slow and works only in close proximity of a satellite containing a nuclear weapon.
"In 2024, a U.S. government official warned that Russia could be developing a new satellite designed to carry nuclear weapons into space. The statement followed the launch of a suspicious Russian satellite into low-Earth orbit in 2022, just a few weeks before the country’s full-scale invasion of Ukraine.
A nuclear detonation in low-Earth orbit — the region about 100 miles to 1,200 miles above Earth’s surface — would release trillions of highly energetic electrons that would destroy many of the satellites in space, disrupting telecommunications networks, GPS, space-based internet, and more.
The 1967 Outer Space Treaty bans the placement of nuclear weapons in space, but there’s currently no way to verify satellites don’t contain nuclear weapons. In fact, no verification methods have even been proposed in unclassified, peer-reviewed literature. ...
In the paper, Danagoulian calculates that a sensor system the size of a large encyclopedia could detect a nuclear weapon with 99 percent accuracy if it orbited within 4,000 meters of the suspect satellite for about a week. He also estimates that the detection time could be cut to a matter of hours if multiple satellite sensors were used or the sensor satellite was able to get within 1,000 meters of the suspect satellite. ..."
From the abstract:
"The Outer Space Treaty (OST) was opened to signatures in 1967 and, since then, 117 countries, including China, the USA and Russia, have become part of it. Among other stipulations, the treaty bans the placement of nuclear weapons in outer space.
Recently, the US government has raised worries that Russia is testing nuclear-armed anti-satellite weapon (ASAT) components, with the possibility that it will place a nuclear weapon in space.
Such a device, if detonated, would destroy most of the satellites in the low Earth orbit. This danger is compounded by the lack of a verification mechanism for the OST.
No methodologies of verification have been proposed in the open peer-reviewed literature.
Here a concept and feasibility study is presented for verifying a satellite’s compliance to the OST by observing the neutrons induced by spallation from the approximately GeV protons in the inner Van Allen radiation belts.
The calculations show that a 9U-CubeSat-sized detection platform can identify a thermonuclear weapon from a distance of 4 km in approximately one week of observation. This conceptual study will stimulate and inform future research and development of verification platforms for the OST."
Verification of the Outer Space Treaty with cosmic protons (no public access)
Verification of the Outer Space Treaty with Cosmic Protons (preprint, open access)
Studying grass grow
Amazing stuff!
"Watching grass grow gets a bad name—studying how grass grows is anything but boring. Grasses include many of our most critical food sources including wheat, rice, and corn. And until recently, nobody was quite sure what factors caused these plants to grow tall.
In a new study, a team of researchers revealed that temperature, not light, determines when grass stems harden, allowing for vertical growth.
To monitor growth, the scientists merged a gene important for the development of the secondary cell wall—the structure that causes grass stems to become rigid—with the gene that makes fireflies glow.
Then, they exposed the plant to a variety of light and temperature conditions and watched how they responded with a time-lapse camera. ...
Neither daylight nor any sort of internal clock had an impact on grass growth. But when the biologists varied the temperature, their grasses responded. In cooler conditions, plants started slowly before rapidly growing; in the heat, grass growth initially spiked but soon dropped to a slower pace.
In addition, pulses of warmth in cool temperatures prompted the greatest growth rates, while cold blasts in the heat ground growth to nearly a halt.
What the study might mean for crop growth, including in the context of climate change, remains unknown. Nevertheless, the findings present new insights into the unexpectedly fascinating process of how grass grows. ..."
From the highlights and abstract:
"Highlights
• Thermocycles, not light or the circadian clock, drive CESA8 rhythms
• CESA8 expression increases during cool nights and declines during warm days
• Secondary-wall gene expression is coordinated with stem elongation
• Warm and cold pulses trigger opposing responses, explained by an incoherent feedforward loop model
Summary
Secondary cell wall thickening is essential for plant structural development, providing the mechanical strength and rigidity required for upright growth. However, direct observation of this process in its endogenous developmental context within living plants has remained limited.
Cellulose, the predominant component of secondary walls and the most abundant biopolymer on Earth, is synthesized at the plasma membrane by complexes containing CELLULOSE SYNTHASE A (CESA) proteins.
Despite its central role, the precise timing and regulation of cellulose deposition during plant development remain unclear.
To address this gap, we developed a real-time bioluminescence imaging system in the model grass Brachypodium distachyon using a luciferase transcriptional reporter driven by the CESA8 cis-regulatory region.
Bioluminescence imaging revealed a consistent spatial pattern of CESA8 expression within elongating internodes, coinciding with regions undergoing secondary wall deposition and progressive increases in cellulose crystallinity. Time-lapse imaging showed that expression follows a robust daily rhythm driven by temperature cycles, independent of light or endogenous circadian signals. Temperature-pulse experiments uncovered rapid, transient inverse responses that were accurately predicted by a mathematical model based on an incoherent feedforward loop.
CESA8 expression correlated strongly with stem elongation, linking structural reinforcement with temperature-driven shoot growth in grasses."
Grasses Provide Most of the World’s Calories—But We’re Only Now Starting to Learn How They Grow (original news release) "UMass Amherst researchers devise technique to show grasses don’t grow like most other plants"
Temperature signals drive grass secondary cell wall thickening (partial public access)
Graphical abstract
Trump admin says it returned Endangered Species Act to original intent by changing 'harm' definition
Good news! Bravo! What took so long! Should have happened on day one in office!
"... This reform is based on the Supreme Court’s 2024 decision in Loper Bright v. Raimondo, which requires agencies to follow the single best meaning of a statute rather than contorting laws to fit political agendas. Using the legally justifiable standard, the Services determined that the prior definition of “harm” was an unlawful regulatory intrusion that interfered with private property rights. ..."
"... The Commerce and Interior Departments said they are rescinding the "outdated" regulatory definition of "harm," stating it will no longer interpret “harm” of a protected species to include modifications to a plant or animal’s habitat that could be detrimental to its survival.
The departments argued that previous administrations "weaponized" the word to block energy production, logging, infrastructure projects and private citizens' land use. ..."
Department of the Interior Restores Clear ESA Enforcement by Rescinding Misguided “Harm” Definition "ESA protections remain in place while reducing burdens for landowners and communities"
Brain glutamate changes could link cannabis use to a higher risk of psychosis
More bad news for e.g. recreational cannabis use! Got to be careful using such drugs!
"... Researchers ... recently carried out a study exploring the possibility that brain glutamate levels could partly explain the relationship between cannabis use and psychotic symptoms. Their paper, published in Molecular Psychiatry, suggests that differences in glutamate levels could be one of the biological pathways linking cannabis use to psychosis. ...
As part of their study, ... examined 79 people with varying levels of psychosis vulnerability. Some of these participants had no known psychiatric conditions and were not experiencing any mental health-related symptoms. Others were considered at a high risk of experiencing psychosis. Finally, a portion of participants were diagnosed with psychosis.
All the participants completed clinical assessments to determine whether they were experiencing positive psychosis symptoms (i.e., hallucinations and delusions), negative psychosis symptoms (i.e., low motivation, a reduced ability to feel pleasure, social withdrawal and a lack of emotional expression), or mood-related symptoms. The researchers also collected information about the patients' cannabis use and analyzed their urine to detect any recent use of the substance.
Finally, the researchers examined the participants' brains using a technique called ultra-high-field 7 Tesla magnetic resonance spectroscopy (1HMRS). This technique allowed them to measure the concentration of specific chemicals in the brain, particularly in a brain region called the anterior cingulate cortex (ACC). ..."
From the abstract:
"Cannabis use is linked to elevated psychosis risk, yet the neurobiological mechanisms that couple use to symptom expression remain unclear. Because glutamatergic dysregulation has been implicated in both cannabis effects and psychosis vulnerability, we examined whether brain glutamate relates to dimensional psychosis symptoms as a function of cannabis use across the psychosis spectrum.
Seventy-nine participants—typically developing controls, clinical high-risk individuals, and patients with psychosis—completed dimensional clinical assessments, detailed cannabis use surveys, urine toxicology, and ultra-high-field 7T magnetic resonance spectroscopy (1HMRS) of the anterior cingulate cortex (ACC).
Linear models assessed the main and interactive effects of ACC glutamate and cannabis use on psychopathology symptoms.
Self-reported cannabis use showed good concordance with urine toxicology, with strongest agreement among frequent users.
Both lower ACC glutamate and higher cannabis use were independently associated with positive and negative psychosis symptoms.
Notably, lower glutamate levels were associated with higher positive symptoms in cannabis users but not cannabis non-users.
Exploratory analyses suggested interactions for depressive and manic symptoms, indicating that glutamatergic abnormalities may amplify the overall severity of cannabis-related symptoms.
Sensitivity analyses revealed lower ACC glutamate in psychosis patients—especially cannabis users—highlighting diagnostic group differences and reinforcing the link between cannabis exposure and glutamatergic dysfunction. These findings implicate ACC glutamatergic dysfunction as a transdiagnostic correlate of symptom burden, particularly in those with psychosis who are cannabis users. Glutamate-targeted interventions and longitudinal designs will be needed to examine causal pathways linking cannabis exposure to psychosis-relevant outcomes."
Cannabis use and glutamate across the psychosis spectrum: in vivo evidence from 7T proton magnetic resonance spectroscopy (open access)
Fig. 1: Individual metabolite quantification and voxel overlap in single-voxel spectroscopy (SVS) ¹HMRS.
Fig. 4: Glutamate × cannabis interactions predicting dimensional psychosis symptoms.
A Unified Framework for Statistical Testing of Invariance
This could be an interesting paper by Stefanie Jegelka!
From the abstract:
"While invariances naturally arise in almost any type of real-world data, no efficient and robust test exists for detecting them in observational data under arbitrarily given group actions.
We tackle this problem by studying discrepancy-based measures of invariance that can capture even subtle distributional asymmetries.
Our first contribution is to show that, while detecting worst-case asymmetries can be computationally intractable, a randomized method can estimate closeness measures to invariance within universal constant factors.
This provides a general framework for statistical testing of invariance under compact group actions.
Despite the extensive and well-established literature on group-based testing, our methodology, to the best of our knowledge, is the first to provide statistical tests for general group invariances with finite-sample guarantees on Type II errors against worst-case alternatives.
We instantiate the framework for common probability discrepancies, including total variation, Wasserstein distances, integral probability metrics, energy distance, and maximum mean discrepancy, obtaining explicit sample-complexity guarantees from empirical convergence rates."
Secretary of State Rubio to host major counterterrorism summit with 60 countries next week in DC
Good news! It has become fairly quiet about Rubio in recent months!
"The State Department said Friday that Secretary of State Marco Rubio is expected to host a large-scale counterterrorism summit in Washington, D.C., next week that will include representatives from over 60 countries.
The summit will focus on the United States' new counterterrorism strategy, which elevates threats from leftist extremist groups such as Antifa by adding anti-propaganda tools and follow-the-money penalties that are designed to neuter political violence inspired by overseas leftists. ..."
President Trump and family: The most corrupt presidency in American history, by the numbers. Really!
Possibly serious stuff! This is a long article with a lot of claims purportedly backed up by facts! I did not have time to double check the many claims etc.
Among other things, the article claims that President Trump pardoned numerous convicted criminal individuals who donated substantial amounts to his campaigns.
It seems his comparison only with President Clinton and his pardoning of March Rich, in the beginning of the article as an introduction, is very selective and possibly flawed.
The author also uses the Watergate Scandal for comparison.
The article failed to provide any tables or lists to summarize the claims.
The immigrant to migrant switch in public discourse
In recent years news media and other sources have avoided the term immigrant and substituted it with migrant. Immigrants and migrants are not the same!
According to Google search: "Migration is the broad, overarching term for any movement of people (or animals) from one location to another, whether across international borders or within a single country.
Immigration is a more specific type of migration that refers exclusively to the act of permanently moving to and settling in a foreign country."
A nice switch in terminology most likely triggered by some ideology!
Are not e.g. gypsies or cross border commuter workers considered to be migrants?
SK Hynix raises $26.5B in the biggest foreign IPO in US history, is urged to build new US fabs
Good news!
Calvin Coolidge 1926: "After all, the chief business of the American people is business. They are profoundly concerned with producing, buying, selling, investing and prospering in the world."
"... This deal, the largest-ever U.S. debut by a non-American company, topped Alibaba’s $25 billion IPO in 2014. ...
The company begins trading on the Nasdaq today, Friday, July 10, under the temporary ticker SKHYV. Regular trading opens Monday, July 13, when the ticker officially becomes SKHY. So far, U.S. investors are lapping it up. The stock opened at 14% over its IPO price, and the price was still rising in early trading on Friday. ..."
Friday, July 10, 2026
Evolution of a core ribosomal innovation in octopus leading to less error prone proteins
Amazing stuff!
"Octopuses are among the strangest creatures on Earth—right down to their molecules. New research has found that octopuses of a certain lineage have a mutation not seen in any other organism that makes their cellular machinery extremely accurate at creating proteins. As a result, their proteins are less likely to form toxic clumps. ...
The team serendipitously discovered a change in the octopus gene encoding ribosomal RNA (rRNA), which is part of the cellular machinery that translates mRNA messages into proteins. This region of the rRNA sequence is identical in every other known organism, from humans to bacteria. But in octopuses, the mutation causes the rRNA to break into two fragments and occurs right at a crucial spot where the rRNA matches the right amino acid to the right genetic instruction. Ribosomes with this break made about 50% fewer errors than other species’ ribosomes when incorporating amino acids into a protein. ..."
From the abstract:
"Much of biology focuses on how genetic changes mediate new functions, but less attention is given to adaptations in other steps of the central dogma.
Octopuses exhibit complex nervous systems and sophisticated behaviors that rival vertebrates, but via an entirely divergent evolutionary history.
Here, we serendipitously discovered that octopus ribosomes contain a structural break in the core ribosomal RNA that is unique among all animals.
This break site enhances translation fidelity to reduce miscoding and subsequent protein aggregation, even when engineered into evolutionarily distant bacterial ribosomes.
Furthermore, high fidelity translation by octopus ribosomes supports proteomic stability during extensive RNA editing observed in cephalopods, suggesting synergy between distinct non-canonical modes of gene regulation.
This adaptation emerged in recently derived octopuses with expanded nervous systems, thereby revealing a mechanism that could broadly support the evolution of novel organismal traits."
Adaptive Innovation in the Octopus Ribosome (PhD dissertation by one of the involved researchers, 2025)
Evolution of a core ribosomal innovation in octopus (preprint, open access)
Figure 1. The octopus has a unique structural adaptation in the conserved ribosomal core
You Don't Need Strong Assumptions: Visual Representation Learning via Temporal Differences
This could be an interesting new paper by Yann LeCun and his team!
From the abstract:
"Progress in AI has largely been driven by methods that assume less. As compute and data increase, approaches with weaker inductive biases generally outperform those with stronger assumptions.
This is particularly characteristic of the field of Visual Representation Learning, where approaches have gone from being dominated by Supervised Learning, to Weakly Supervised Learning, to the now widespread success of Self-Supervised Learning without human labels.
Yet, even modern Self-Supervised Learning approaches still depend on strong inductive biases such as augmentations, masking, or cropping. If this trend holds, even these remaining biases should become bottlenecks at scale -- and our experiments confirm this: the optimal strength of inductive biases decreases as data grows.
This motivates the search for approaches that rely on fewer assumptions. To this end, we introduce Temporal Difference in Vision (TDV), a new paradigm for self-supervised learning from video that avoids existing inductive biases, relying instead on a causal assumption that the past causes the future.
TDV functions by jointly training an image encoder and a motion encoder so that the current frame's representation plus the encoded motion equals the next frame's representation. Despite not leveraging any strong inductive biases, TDV matches state-of-the-art recipes on dense spatial tasks, laying the foundation for representation learning without strong assumptions."
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