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The phytochrome B (phyB) photoreceptor and EARLY FLOWERING 3 (ELF3) are two major plant thermosensors that monitor high temperatures primarily at night. However, high temperatures naturally occur during the daytime; the mechanism of daytime thermosensing and whether these thermosensors can also operate under intense sunlight remain ambiguous. Here, we show that phyB plays a substantial role in daytime thermosensing in Arabidopsis, and its thermosensing function becomes negligible only when the red light intensity reaches 50 μmol m −2  s −1 . Leveraging this restrictive condition for phyB thermosensing, we reveal that triggering daytime thermomorphogenesis requires two additional thermosensory pathways. High temperatures induce starch breakdown in chloroplasts and the production of sucrose, which stabilizes the central thermal regulator PHYTOCHROME-INTERACTING FACTOR 4 (PIF4) by antagonizing phyB-dependent PIF4 degradation. In parallel, high temperatures release the inhibition of PIF4 transcription and PIF4 activity by ELF3. Thus, our study elucidates a multisensor high-temperature signaling framework for understanding diverse thermo-inducible plant behaviors in daylight. Plants encounter high temperatures concomitantly with intense sunlight during the daytime. Here, the authors reveal a concerted chloroplast and nucleus high-temperature signaling framework that gates daytime thermomorphogenesis in Arabidopsis.

Experimental studies of the collisions of heavy nuclei at relativistic energies have established the properties of the quark–gluon plasma (QGP), a state of hot, dense nuclear matter in which quarks and gluons are not bound into hadrons1–4. In this state, matter behaves as a nearly inviscid fluid5 that efficiently translates initial spatial anisotropies into correlated momentum anisotropies among the particles produced, creating a common velocity field pattern known as collective flow. In recent years, comparable momentum anisotropies have been measured in small-system proton–proton (p+p) and proton–nucleus (p+A) collisions, despite expectations that the volume and lifetime of the medium produced would be too small to form a QGP. Here we report on the observation of elliptic and triangular flow patterns of charged particles produced in proton–gold (p+Au), deuteron–gold (d+Au) and helium–gold (3He+Au) collisions at a nucleon–nucleon centre-of-mass energy \\[ s_NN\\] = 200 GeV. The unique combination of three distinct initial geometries and two flow patterns provides unprecedented model discrimination. Hydrodynamical models, which include the formation of a short-lived QGP droplet, provide the best simultaneous description of these measurements.

According to the CPT theorem, which states that the combined operation of charge conjugation, parity transformation and time reversal must be conserved, particles and their antiparticles should have the same mass and lifetime but opposite charge and magnetic moment. Here, we test CPT symmetry in a nucleus containing a strange quark, more specifically in the hypertriton. This hypernucleus is the lightest one yet discovered and consists of a proton, a neutron and a Λ hyperon. With data recorded by the STAR detector 1 – 3 at the Relativistic Heavy Ion Collider, we measure the Λ hyperon binding energy B Λ for the hypertriton, and find that it differs from the widely used value 4 and from predictions 5 – 8 , where the hypertriton is treated as a weakly bound system. Our results place stringent constraints on the hyperon–nucleon interaction 9 , 10 and have implications for understanding neutron star interiors, where strange matter may be present 11 . A precise comparison of the masses of the hypertriton and the antihypertriton allows us to test CPT symmetry in a nucleus with strangeness, and we observe no deviation from the expected exact symmetry. The STAR collaboration reports a measurement of the mass difference and binding energy of the hypertriton and its antiparticle. This work constrains the hyperon–nucleon interaction and allows us to test the CPT theorem in a nucleus with strangeness.

The core light-harvesting complexes (LH1) in bacteriochlorophyll (BChl) b-containing purple phototrophic bacteria are characterized by a near-infrared absorption maximum around 1010 nm. The determinative cause for this ultra-redshift remains unclear. Here, we present results of circular dichroism (CD) and resonance Raman measurements on the purified LH1 complexes in a reaction center-associated form from a mesophilic and a thermophilic Blastochloris species. Both the LH1 complexes displayed purely positive CD signals for their Qy transitions, in contrast to those of BChl a-containing LH1 complexes. This may reflect differences in the conjugation system of the bacteriochlorin between BChl b and BChl a and/or the differences in the pigment organization between the BChl b- and BChl a-containing LH1 complexes. Resonance Raman spectroscopy revealed remarkably large redshifts of the Raman bands for the BChl b C3-acetyl group, indicating unusually strong hydrogen bonds formed with LH1 polypeptides, results that were verified by a published structure. A linear correlation was found between the redshift of the Raman band for the BChl C3-acetyl group and the change in LH1-Qy transition for all native BChl a- and BChl b-containing LH1 complexes examined. The strong hydrogen bonding and π–π interactions between BChl b and nearby aromatic residues in the LH1 polypeptides, along with the CD results, provide crucial insights into the spectral and structural origins for the ultra-redshift of the long-wavelength absorption maximum of BChl b-containing phototrophs.

Partons traversing the strongly interacting medium produced in heavy-ion collisions are expected to lose energy depending on their color charge and mass. We measure the nuclear modification factors for charm- and bottom-decay electrons, defined as the ratio of yields, divided by the number of binary nucleon–nucleon collisions, in sNN=200 GeV Au+Au collisions to p+p collisions (RAA), or in central to peripheral Au+Au collisions (RCP). We find the bottom-decay electron RAA and RCP to be significantly higher than those of charm-decay electrons. Model calculations including mass-dependent parton energy loss in a strongly coupled medium are consistent with the measured data. These observations provide evidence of mass ordering of charm and bottom quark energy loss when traversing through the strongly coupled medium created in heavy-ion collisions.

A mass-flow calorimetry system has been installed to investigate the excess power phenomenon at elevated temperatures. The first trial runs with a silica-included Cu·Ni nano-composite sample (CNS) containing 4.1 g of Ni showed an implication of a few days lasting excess power of 5 W/g-Ni. Next, a oxidCu·Ni·Zr e nanocomposite sample (CNZ4) containing 61 g of Ni has been examined to show excess power of 15 W lasting for 3 days and gradually increasing at a rate of 10 W per 3 weeks. Each corresponds to 30 eV/atom-Ni and 100 eV/atom-Ni, implying a nuclear origin of the excess energy.

Aim: To compare the performance of keratoconus, penetrating keratoplasty (PK), and control subjects on clinical tests of contrast and glare vision, to determine whether differences in vision were independent of visual acuity (VA), and thereby establish which vision tests are the most useful for outcome studies of PK for keratoconus. Methods: All PK subjects had keratoconus before grafting and no subjects had any other eye disease. The keratoconus (n = 11, age 35.0 (SD 11.1) years), forme fruste keratoconus (n = 6, 33.0 (13.0)), PK (n = 21, 41.2 (7.9)), and control (n = 24, 33.7 (8.6)) groups were similar in age. Vision testing, conducted with optimal refractive correction in place, included low contrast visual acuity (LCVA) and Pelli-Robson contrast sensitivity (PRCS) both with and without glare, as well as VA. Results: Normal subjects saw better than PK subjects who in turn saw better than keratoconus subjects on all raw measures. However, when adjusted for VA, the normal group only saw significantly better than the keratoconus group on LCVA (low contrast loss 0.05 (0.04) v 0.15 (0.12), F2,48 = 6.16; p<0.01, post hoc Sheffé p<0.05), and the decrements to glare were no worse than for normals. The forme fruste keratoconus group were indistinguishable from normals on all measures. Conclusions: PK subjects have superior vision to keratoconus subjects, but not as good as normal subjects. Including mild keratoconus subjects within a keratoconus group could confound these differences in vision. While VA is an excellent test for comparing normal, keratoconus and PK groups, additional information can be provided by LCVA and PRCS, but not by glare testing. Outcomes research into keratoconus management should include a measure in the contrast domain.

Atomic nuclei are self-organized, many-body quantum systems bound by strong nuclear forces within femtometre-scale space. These complex systems manifest a variety of shapes 1 – 3 , traditionally explored using non-invasive spectroscopic techniques at low energies 4 , 5 . However, at these energies, their instantaneous shapes are obscured by long-timescale quantum fluctuations, making direct observation challenging. Here we introduce the collective-flow-assisted nuclear shape-imaging method, which images the nuclear global shape by colliding them at ultrarelativistic speeds and analysing the collective response of outgoing debris. This technique captures a collision-specific snapshot of the spatial matter distribution within the nuclei, which, through the hydrodynamic expansion, imprints patterns on the particle momentum distribution observed in detectors 6 , 7 . We benchmark this method in collisions of ground-state uranium-238 nuclei, known for their elongated, axial-symmetric shape. Our findings show a large deformation with a slight deviation from axial symmetry in the nuclear ground state, aligning broadly with previous low-energy experiments. This approach offers a new method for imaging nuclear shapes, enhances our understanding of the initial conditions in high-energy collisions and addresses the important issue of nuclear structure evolution across energy scales. The collective-flow-assisted nuclear shape-imaging method images the nuclear global shape by colliding them at ultrarelativistic speeds and analysing the collective response of outgoing debris.

Notwithstanding decades of progress since Yukawa first developed a description of the force between nucleons in terms of meson exchange 1 , a full understanding of the strong interaction remains a considerable challenge in modern science. One remaining difficulty arises from the non-perturbative nature of the strong force, which leads to the phenomenon of quark confinement at distances on the order of the size of the proton. Here we show that, in relativistic heavy-ion collisions, in which quarks and gluons are set free over an extended volume, two species of produced vector (spin-1) mesons, namely ϕ and K *0 , emerge with a surprising pattern of global spin alignment. In particular, the global spin alignment for ϕ is unexpectedly large, whereas that for K *0 is consistent with zero. The observed spin-alignment pattern and magnitude for ϕ cannot be explained by conventional mechanisms, whereas a model with a connection to strong force fields 2 – 6 , that is, an effective proxy description within the standard model and quantum chromodynamics, accommodates the current data. This connection, if fully established, will open a potential new avenue for studying the behaviour of strong force fields. At the Relativistic Heavy Ion Collider, observations of two meson species produced by heavy-ion collisions, ϕ and K *0 , show surprising patterns of global spin alignment, being unexpectedly large and consistent with zero, respectively.