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At least 721 records · Page 40

Materials Data on Dy3Lu by Materials Project

LuDy3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Lu is bonded to twelve Dy atoms to form LuDy12 cuboctahedra that share corners with four equivalent LuDy12 cuboctahedra, corners with eight equivalent DyDy8Lu4 cuboctahedra, edges with eight equivalent LuDy12 cuboctahedra, edges with sixteen equivalent DyDy8Lu4 cuboctahedra, faces with four equivalent LuDy12 cuboctahedra, and faces with fourteen DyDy8Lu4 cuboctahedra. All Lu–Dy bond lengths are 3.52 Å. There are two inequivalent Dy sites. In the first Dy site, Dy is bonded to four equivalent Lu and eight Dy atoms to form DyDy8Lu4 cuboctahedra that share corners with twelve equivalent DyDy8Lu4 cuboctahedra, edges with eight equivalent LuDy12 cuboctahedra, edges with sixteen DyDy8Lu4 cuboctahedra, faces with four equivalent LuDy12 cuboctahedra, and faces with fourteen DyDy8Lu4 cuboctahedra. All Dy–Dy bond lengths are 3.52 Å. In the second Dy site, Dy is bonded to four equivalent Lu and eight equivalent Dy atoms to form DyDy8Lu4 cuboctahedra that share corners with four equivalent DyDy8Lu4 cuboctahedra, corners with eight equivalent LuDy12 cuboctahedra, edges with twenty-four DyDy8Lu4 cuboctahedra, faces with six equivalent LuDy12 cuboctahedra, and faces with twelve DyDy8Lu4 cuboctahedra.

36 MATERIALS SCIENCE↗

Materials Data on LuN7O15 by Materials Project

Lu(NO3)5N2 crystallizes in the trigonal P3_1 space group. The structure is zero-dimensional and consists of six ammonia molecules and three Lu(NO3)5 clusters. In each Lu(NO3)5 cluster, Lu3+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Lu–O bond distances ranging from 2.36–2.51 Å. There are five inequivalent N+3.86+ sites. In the first N+3.86+ site, N+3.86+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.23 Å) and two longer (1.28 Å) N–O bond length. In the second N+3.86+ site, N+3.86+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.23 Å) and two longer (1.28 Å) N–O bond length. In the third N+3.86+ site, N+3.86+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.23–1.29 Å. In the fourth N+3.86+ site, N+3.86+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.23–1.28 Å. In the fifth N+3.86+ site, N+3.86+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.22 Å) and two longer (1.28 Å) N–O bond length. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Lu3+ and one N+3.86+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one N+3.86+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one Lu3+ and one N+3.86+ atom. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to one Lu3+ and one N+3.86+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Lu3+ and one N+3.86+ atom. In the sixth O2- site, O2- is bonded in a distorted L-shaped geometry to one Lu3+ and one N+3.86+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one N+3.86+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one Lu3+ and one N+3.86+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one N+3.86+ atom. In the tenth O2- site, O2- is bonded in a distorted water-like geometry to one Lu3+ and one N+3.86+ atom. In the eleventh O2- site, O2- is bonded in a single-bond geometry to one N+3.86+ atom. In the twelfth O2- site, O2- is bonded in a distorted water-like geometry to one Lu3+ and one N+3.86+ atom. In the thirteenth O2- site, O2- is bonded in a single-bond geometry to one N+3.86+ atom. In the fourteenth O2- site, O2- is bonded in a distorted L-shaped geometry to one Lu3+ and one N+3.86+ atom. In the fifteenth O2- site, O2- is bonded in a distorted single-bond geometry to one Lu3+ and one N+3.86+ atom.

36 MATERIALS SCIENCE↗

Novel theranostic agent for PET imaging and targeted radiopharmaceutical therapy of tumour-infiltrating immune cells in glioma

Background: Malignant gliomas are deadly tumours with few therapeutic options. Although immunotherapy may be a promising therapeutic strategy for treating gliomas, a significant barrier is the CD11b + tumour-associated myeloid cells (TAMCs), a heterogeneous glioma infiltrate comprising up to 40% of a glioma's cellular mass that inhibits anti-tumour T-cell function and promotes tumour progression. A theranostic approach uses a single molecule for targeted radiopharmaceutical therapy (TRT) and diagnostic imaging; however, there are few reports of theranostics targeting the tumour microenvironment. Methods: Utilizing a newly developed bifunctional chelator, Lumi804, an anti-CD11b antibody (αCD11b) was readily labelled with either Zr-89 or Lu-177, yielding functional radiolabelled conjugates for PET, SPECT, and TRT. Findings: 89 Zr/ 177 Lu-labeled Lumi804-αCD11b enabled non-invasive imaging of TAMCs in murine gliomas. Additionally, 177 Lu-Lumi804-αCD11b treatment reduced TAMC populations in the spleen and tumour and improved the efficacy of checkpoint immunotherapy. Interpretation: 89 Zr- and 177 Lu-labeled Lumi804-αCD11b may be a promising theranostic pair for monitoring and reducing TAMCs in gliomas to improve immunotherapy responses.

60 APPLIED LIFE SCIENCES↗

Adsorption of rare earth elements in carboxylated mesoporous carbon

The separation of Rare Earth Elements (REEs) from various non-conventional sources is critically important to maintain the supply–demand balance of REEs in the western world. Here, in this research, we have investigated coal Fly Ash (CFA) as the non-conventional source of REEs. In order to recover REEs, we have synthesized carboxylate-functionalized mesoporous carbon (CMC) to harness the chelation-induced adsorption of REEs. These adsorbents were characterized with pore textural properties, FTIR spectroscopy, and SEM-EDX mapping. In the initial study with single-component La(III) Dy(III) and Lu(III), it was revealed that CMC can adsorb those REEs 2–4 times more than that of pristine mesoporous carbon confirming the effective role of the carboxylate group in the REE separation. Furthermore, the affiliation of the carboxylate group towards heavier REEs (Lu>Dy>La, when present is equal amounts) provides an added benefit of this adsorbent owing to the high demand for heavier REEs in the technology sectors. The leachate solution produced from CFA contained sixteen REEs in the range of 50–200 ppb for most of the REEs. It was revealed that CMC can extract 80–90% of all the REEs thereby further confirming the success of the CMC as an effective REE sorbent. Three successive cycles of adsorption and desorption of REEs with the same CMC revealed the consistent adsorption capacity of REEs. In-situ X-ray Absorption Near Edge Spectroscopy (XANES) analysis confirmed the +3 oxidation states of La, Dy, and Lu within CMC. In-situ Extended X-ray Absorption Fine Structure (EXAFS) analysis revealed the shortening of mean La-O, Dy-O, and Lu-O bond distance by 0.03–0.05 Å thereby confirming the coordination of these REEs with carboxylate groups present on CMC.

36 MATERIALS SCIENCE↗

Ionic Contraction across the Lanthanide Series Decreases the Temperature-Induced Disorder of the Water Coordination Sphere

In liquid, temperature affects the structures of lanthanide complexes in multiple ways that depend upon complex interactions between ligands, anions, and solvent molecules. The relative simplicity of lanthanide aqua ions (Ln 3+ ) make them well suited to determine how temperature induces structural changes in lanthanide complexes. In this work, we performed a combination of ab initio molecular dynamics (AIMD) simulations and extended X-ray absorption fine structure (EXAFS) measurements, both at 25 and 90 °C, to determine how temperature affects the first- and second-coordination spheres of three Ln 3+ (Ce 3+ , Sm 3+ , and Lu 3+ ) aqua ions. AIMD simulations show first lanthanide coordination spheres that are similar at 25 and 90 °C, more so for the Lu 3+ ion that remains as eight-coordinate than for the Ce 3+ and Sm 3+ ions that change their preferred coordination number from nine (at 25 °C) to eight (at 90 °C). The measured EXAFS spectra are very similar at 25 and 90 °C, for the Ce 3+ , Sm 3+ , and Lu 3+ ions, suggesting that the dynamical disorder of the Ln 3+ ions in liquid water is sufficient such that temperature-induced changes do not clearly manifest changes in the structure of the three ions. Both AIMD simulations and EXAFS measurements show very similar structures of the first coordination sphere of the Lu 3+ ion at 25 and 90 °C.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Influence of Rare-Earth Ion Radius on Metal–Metal Charge Transfer in Trinuclear Mixed-Valent Complexes

We report the synthesis and characterization of a highly conjugated bisferrocenyl pyrrolediimine ligand, Fc 2 PyrDIH (1), and its trinuclear complexes with rare earth ions—(Fc 2 PyrDI)M(N(TMS) 2 ) 2 (2-M, M = Sc, Y, Lu, La). Crystal structures, NMR spectra, and UV/Vis-NIR data are presented. The latter are in good agreement with DFT calculations, illuminating the impact of the rare earth ionic radius on NIR charge transfer excitations. For [2-Sc] + , the charge transfer is at 11500 cm -1 , while for [2-Y] + only a d-d transition at 8000 cm -1 is observed. Lu has an ionic radius in between Sc and Y, and the [2-Lu] + complex exhibits both transitions. From TDDFT analysis we assign the 11500 cm -1 transition as a mixture of MLCT and MMCT, rather than pure metal-to-metal CT, because it has significant ligand character. Typically, the ferrocenes have high rotational freedom in bis-ferrocenyl mixed valent complexes. However, in the present (Fc 2 PyrDI)M(N(TMS) 2 ) 2 complexes, ligand-ligand repulsions lock the rotational freedom, so that rare earth ionic radius-dependent geometric differences increasingly influence orbital overlap as the ionic radius falls. The Marcus-Hush coupling constant HAB trends as: [2-Sc] + >[2-Lu] + >[2-Y] +

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Heavy Versus Light Lanthanide Selectivity for Graphene Oxide Films is Concentration Dependent

Rare earths are important materials in various technologies such as catalysis and optoelectronics. Graphene oxide (GO) is a promising material for separation applications, including the isolation of lanthanides from complex mixtures. Previous works using fatty acid monolayers have demonstrated preferential heavy versus light lanthanide adsorption, which has been attributed to differences in lanthanide ion size. In this work, we used interfacial X-ray fluorescence measurements to reveal that GO thin films at the air/water interface have no lanthanide selectivity for dilute subphases. However, at high subphase concentrations, ~8 times more Lu is adsorbed than La. By comparing the GO results with an ideal monolayer with a carboxylic acid headgroup, arachidic acid (AA), we demonstrate that the number of Lu ions adsorbed to GO is significantly higher than the number expected to compensate for the surface charge. Vibrational sum frequency generation (SFG) spectroscopy results on both GO thin films and AA monolayers reveal a red-shifted SFG signal in the OH region, which we attribute to partial dehydration of the adsorbed ions and carboxylic acid headgroups. Liquid surface X-ray reflectivity data show that the GO thin film structure does not significantly change between the very dilute and concentrated subphases. We speculate that the functional groups of both GO and AA facilitate cation dehydration, which is essential for ion adsorption. Heavy lanthanide Lu has stronger ion–ion correlations that can overcome the electrostatic repulsion between cations at higher concentrations compared to light lanthanide La, meaning GO and AA can exhibit apparent overcharge with Lu. Lastly, the layered structure of the GO films and reactive chemical nature of GO itself can accommodate ion adsorption.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Fiber coupled laser ultrasound system using a single mode hollow core fiber for excitation laser: Theory and demonstration for on-machine thickness gauging

Laser ultrasound (LU) is a technique that uses a pump laser and a probe laser to optically generate and detect elastic waves in a material. Despite its advantages over traditional contact transducer-based ultrasound, industrial adoption has been limited by complex optical setups and the inability of multi-mode fibers to deliver a stable Gaussian profile for the pump laser. Here, we report a fully fiber-coupled thermoelastic LU system that uses an anti-resonant hollow-core single-mode fiber to deliver 1 mJ nanosecond pulses of 1064 nm light, while preserving the fundamental Gaussian mode (pump laser). When combined with a fiber-coupled interferometer (probe laser), a small, flexible, and environmentally robust sensor capable of optically generating and detecting high frequency broadband ultrasound is realized. We demonstrate such an LU system implemented in situ on a four-axis precision lathe. High-resolution thickness gauging is performed, before and after precision cutting, by exciting and measuring a zero-group velocity guided wave mode. The measurements are verified with ex-situ traceable coordinate measuring machine data. Mean absolute deviations of 0.1%, of nominal thickness, before cutting, and 0.2% and 0.3%, after stepped and tapered cuts, respectively, are reported. A theoretical background for thermoelastic ultrasound generation in an elastic waveguide is also presented. Attention is given to the effect of the pump laser profile on wave generation to elucidate the importance of using single-mode laser light. The fiber-coupled system demonstrated is well-suited for use in scientific and engineering sensing applications and facilitates the adoption of LU for industrial non-destructive testing.

Engineering↗

Role of Lithium Codoping in Enhancing the Scintillation Yield of Aluminate Garnets

The aim of this work is to clarify the scintillation-yield enhancement in Lu YAG : Pr scintillators obtained by Li codoping via integrated study of the valence state of activators, the preferential site occupancy of Li codopants, and defect structures from experimental and theoretical insights. Here, with Li codoping, the light yield and energy resolution of 10 × 10 × 10 mm 3 Lu YAG : Pr samples are improved from 156000 to 248000 photons/MeV, and 5.3 to 4.3% at 662 keV,respectively.The optical absorption spectra indicate that Li codoping does not induce conversion of stable Pr 3 + to Pr 4 + in Lu YAG : Pr single crystals. Based on the formation energies of substitutional and interstitial Li sites using density-functional-theory (DFT) calculations and the 7 Li nuclear magnetic resonance results, it is shown that the Li ions prefer to dominantly occupy the fourfold coordinated interstitial sites and fourfold coordinated Al sites. The systematic analysis of thermoluminescence glow curves, positron annihilation lifetime spectroscopies, and defect formation energies derived from DFT calculations reveals that the concentration of isolated Lu and Al vacancies as dominant acceptor defects is reduced by Li codoping, whilst the shallow Li i interstitial defects and the deep V O oxygen vacancies are introduced simultaneously. We propose that the lowering of hole trapping at defects resulting from Li codoping contributes to the scintillation-yield enhancement.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Frustration-mediated crossover from long-range to short-range magnetic ordering in Y 1 – x L u x BaC o 4 O 7

The R⁢BaC⁢o 4⁢ O 7 system is a prototype geometrically frustrated magnet in which kagome planes and triangular layers of Co-O tetrahedra interleave. For R=Y, an antiferromagnetic ground state is realized due to a frustration-breaking trigonal-orthorhombic phase transition. For R = Lu, however, a long-range ordered state has rarely, if ever, been reported despite a similar symmetry-breaking transition, albeit at a significantly lower temperature. To explore this dichotomy, we present a comprehensive magnetic and structural phase diagram for Y 1-x L⁢u x BaC⁢o 4 ⁢O 7 , established through complementary neutron diffraction and magnetization measurements. Our results outline the phase evolution of the nuclear structures in response to changes in composition and temperature. Further, the temperature of the trigonal (P⁢31⁢c) to orthorhombic (Pbn⁢2 1 ) transition, T s⁢1 , decreases monotonically with increasing Lu content from 310 K for x = 0.0 to 110 K for x = 1.0. In Lu-rich compositions (0.7 ≤ x ≤ 1.0), first-order structural transitions are observed with coexisting and competing orthorhombic Pbn⁢2 1 and metastable monoclinic Cc phases. For the magnetically ordered Y-rich compositions, T- and x-dependent refinements of the magnetic structure reveal an antiferromagnetic “ribbonlike” arrangement of Co spin pairs in both the triangular and the kagome layers. A gradual suppression of long-range magnetic order is observed with increasing the Lu content, accompanied by the development of short-range magnetic correlations present in all the samples.

36 MATERIALS SCIENCE↗

Synthesis of DOTA-Based 43 Sc Radiopharmaceuticals Using Cyclotron-Produced 43 Sc as Exemplified by [ 43 Sc]Sc-PSMA-617 for PSMA PET Imaging

The implementation of theranostics in oncologic nuclear medicine has exhibited immense potential in improving patient outcomes in prostate cancer with the implementation of [ 68 Ga]Ga-PSMA-11 PET and [ 177 Lu]Lu-PSMA-617 into clinical practice. However, the correlation between radiopharmaceutical biodistributions seen with [ 68 Ga]Ga-PSMA-11 PET imaging and downstream [ 177 Lu]Lu-PSMA-617 therapy remains imperfect. This suggests that prostate cancer theranostics could potentially be further refined through the implementation of true theranostics, tandem pairs of diagnostic and therapeutic radiopharmaceuticals that utilize the same ligand and element, thus yielding identical pharmacokinetics. The radioscandiums are one such group of true theranostic radiopharmaceuticals. The radioscandiums consist of two β+ emitting scandium isotopes ( 43 Sc/ 44 Sc), as well as a β − emitting therapeutic isotope ( 47 Sc), which can all conjugate with PSMA-targeting PSMA-617. This potential has led to extensive investigations into the production of the radioscandiums as well as pre-clinical assessments with several ligands; however, there is a lack of literature extensively describing the complete synthesis of scandium radiopharmaceuticals. which therefore limits the accessibility of radioscandium research in theranostics. As such, this work aims to present an easily translatable protocol for the synthesis of [ 43 Sc]Sc-PSMA-617 from a [ 42 Ca]CaCO 3 starting material, including target formation, nuclear production via 42 Ca(d,n) 43 Sc reaction, chemical separation, radiolabeling, solvent reformulation, and target recycling.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Expedition 7 Crew Interview: Yuri Malenchenko

Cosmonaut Yuri Malenchenko of Expedition Seven is seen during a pre-launch interview. He begins by telling why he wanted to become a cosmonaut. Malenchenko expresses his reaction about the news of the Space Shuttle Columbia accident, and how this mission will be different from other missions. He also expresses the challenges that face Malenchenko and Ed Lu such as the crew reduction from three to two, less supplies and no space shuttle flights. Malenchenko says that he will have to work on a compressed schedule, which will make the mission even more challenging. A description of the handover of Expedition Six is given. Malenchenko and Ed Lu will be cramped in a confined space on the Soyuz Spacecraft for two days before docking, and he talks about this experience. Lastly, Malenchenko gives his thoughts on how it will be to work with Ed Lu in space, and tells of Lu's trustworthiness and reliability as a fellow crew member.

Source record↗

SWCX Emission from the Helium Focusing Cone - Model to Data Comparison

A model for heliospheric solar wind charge exchange (SWCX) X-ray emission is applied to a series of XMM-Newton observations of the interplanetary focusing cone of interstellar helium. The X-ray data are from three coupled observations of the South Ecliptic Pole (SEP, to observe the cone) and the Hubble Deep Field-North (HDFN. to monitor global variations of the SWCX emission due to variations in the solar wind) from the period 24 November to 15 December 2003. There is good qualitative agreement between the model predictions and thc data with the maximum SWCX flux observed at an ecliptic longitude of approx. 72deg, consistent with the central longitude of the He cone. We observe a total excess of 2.1 +/- 1.3 LU in the O VII line and 2.0 +/- 0.9 LU in the 0 VIII line. However. the SWCX emission model, which was adjusted for solar wind conditions appropriate for late 2003, predicts an excess from the He cone of only 0.5 LU and 0.2 LU, respectively, in the O VII and O VIII lines. We discuss thc model to data comparison and provide possible explanations for the discrepancies. We also qualitatively reexamine our SWCX n~ocicl predictions in the 1/4 keV band with data from the ROSAT All-Sky Survey towards the North and South Ecliptic Poles, when the He cone was probably first detected in soft X-rays.

Koutroumpa, D.↗

XMM-Newton Observations of MBM 12: More Constraints on the Solar Wind Charge Exchange and Local Bubble Emissions

We present the first analysis of an XMM-Newton observation of the nearby molecular cloud MBM 12. We find that in the direction of MBM 12 the total O VII (0.57 keV) triplet emission is 1.8(+0.5/-0.6) photons/sq cm/s/sr (or Line Units - LU) while for the O VIII (0.65 keV) line emission we find a 3(sigma) upper limit of <1 LU. We also use a heliospheric model to calculate the O VII and O VIII emission generated by Solar Wind Charge-eXchange (SWCX) which we compare to the XMM-Newton observations. This comparison provides new constraints on the relative heliospheric and Local Bubble contributions to the local diffuse X-ray background. The heliospheric SWCX model predicts 0.82 LU for O VII, which accounts for approx. 46+/-15% of the observed value, and 0.33 LU for the O VIII line emission consistent with the XMM-Newton observed value. We discuss our results in combination with previous observations of the MBM 12 with CHANDRA and Suzaku.

Koutroumpa, Dimitra↗

Materials Data on LuB6 by Materials Project

LuB6 is Calcium hexaboride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Lu is bonded in a 1-coordinate geometry to twenty-four equivalent B atoms. All Lu–B bond lengths are 2.99 Å. B is bonded in a 1-coordinate geometry to four equivalent Lu and five equivalent B atoms. There is one shorter (1.62 Å) and four longer (1.74 Å) B–B bond length.

36 MATERIALS SCIENCE↗

Materials Data on Lu2AlSi2 by Materials Project

Lu2AlSi2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Lu is bonded in a 10-coordinate geometry to six equivalent Si atoms. All Lu–Si bond lengths are 2.94 Å. Al is bonded in a 12-coordinate geometry to four equivalent Si atoms. All Al–Si bond lengths are 2.60 Å. Si is bonded in a 9-coordinate geometry to six equivalent Lu, two equivalent Al, and one Si atom. The Si–Si bond length is 2.40 Å.

36 MATERIALS SCIENCE↗

Materials Data on LuRh3C by Materials Project

LuRh3C is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Lu is bonded to twelve equivalent Rh atoms to form LuRh12 cuboctahedra that share corners with twelve equivalent LuRh12 cuboctahedra, faces with six equivalent LuRh12 cuboctahedra, and faces with eight equivalent CRh6 octahedra. All Lu–Rh bond lengths are 2.94 Å. Rh is bonded to four equivalent Lu and two equivalent C atoms to form a mixture of distorted face, edge, and corner-sharing RhLu4C2 octahedra. The corner-sharing octahedra tilt angles range from 0–60°. Both Rh–C bond lengths are 2.08 Å. C is bonded to six equivalent Rh atoms to form CRh6 octahedra that share corners with six equivalent CRh6 octahedra and faces with eight equivalent LuRh12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗

Materials Data on LuSi2 by Materials Project

LuSi2 is hexagonal omega structure structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Lu is bonded to twelve equivalent Si atoms to form a mixture of edge and face-sharing LuSi12 cuboctahedra. All Lu–Si bond lengths are 3.03 Å. Si is bonded in a 9-coordinate geometry to six equivalent Lu and three equivalent Si atoms. All Si–Si bond lengths are 2.36 Å.

36 MATERIALS SCIENCE↗